Patrick Abellard
email: abellard@univ-tln.fr

Karine Bartalucci
email: k.bartalucci@adapei83.fr

Alexandre Abellard

COMM' HANDI : For a Different Communication

Keywords: Polyhandicap, Communication, Sensory disorder, Symbolization, Adapted Specific Material

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Introduction

In communication, three facts must be considered as important parameters: will to communicate, being able to communicate and knowing how to communicate [1]. For the multihandicapped person, the dependence is particularly efficient when the speech ability is absent under its articulated form. However, the multi-handicapped people can communicate in their different own way and we shall then list their capacities of communicating with other people.

Observing behavior is an effectient way to establish a communication assesment which must be completed by the preliminary consideration of the sensory disorders (confusions) and by family and interdisciplinary observations. For example, the analysis of movements, look, singing exercises…. can allow to define specific equipments in order to ease the expression of needs, choices, feelings... The main difficulty in the elaboration of a personalized for communication lies in the development of specifically designed equipments adapted to capacities and difficulties of a young polyhandicapped person. That is why a partnership was set up since 2014 between the University of Toulon (I3M laboratory and IUT Institute) and ADAPEI Association (University providing the technical skills in realizing the projects). This collaboration results in several projects of communication interfaces realized with students of IUT Electrical Engineering Department. This common work won an "Espoir de l'innovation" award during the last "Var Terre d'Innovation" contest organized by Var Departemental Council (equivalent of county) First, "polyhandicap" term will be defined and the relation of communication of/with the multi-handicapped child will be specified. Some ideas will be detailed, in particular on how taking into account, exploiting and of developping the existing means of communication, and how to lead these people towards the discovery of their symbolization possibilities. Then, tools set up in an establishment for children and multi-handicapped teenagers will be more particularly described in their two important functions : identification and contact facilitation. Clinical cases will be presented afterwards to understand better the individual work that needs to be performed so as to improve the relation of communication with the multi-handicapped child. Finally, emergent working hypotheses will be discussed.

Polyhandicap

Polyhandicap is "a serious multi-expression handicap, associating severe or deep driving and mental deficiencies, causing an extreme limitation of autonomy, perception possibilities, expression and relation". This definition includes numerous clinical expressions, according to the prevailing of either the motor or mental disability. Polyhandicap can be even worsen by other deficiencies or disorders. It requires specialized techniques in medical follow-up, learning relation and communication means, development of the intellectual and sensorimotor learning capacities that contributes to the exercice of an optimal autonomy [START_REF]Annexes XXIV Ter au décret n°89-798 du 27 octobre 1989 relatives aux conditions de prise en charge des enfants ou adolescents polyhandicapés par les établissements et services d'éducation spéciale[END_REF]. Specialists generally agree on polyhandicap causes : 20% accidental, 20% viral, 20% genetics, 40% still being unexplained. The functional effects of the various deficiencies change as the child is growing up. The initial handicap can worsen with secondary handicaps. For example, the behavior disorders (stereotypies, auto-aggressiveness, psychotic fold) can take an important place and make difficult to draw the line between polyhandicap and very regressive overdrawn psychoses.

The intellectual deficiency of the polyhandicapped person results in difficulties to understand his spatio-temporal location as well as memorization troubles, reasoning confusions, misunderstanding of relations between situations, and most of the time, the absence of articulated language. The possibilities of expressing feelings are however preserved as well as the contact with the environment. To obtain autonomy, medical care has to include the development of the skills and not be based on the missing capacities of the person.

Concerning motor disorders, they are practically constant. Epilepsy affects 40 to 50 % of multi-handicapped people and 20-25% have difficulties to balance epilespsy. Sensory disorders are a part of multi-handicapped persons invalidating problems. They get worse as the person is getting older. Essentially, these disorders are audition problemsthat are difficult to evaluate, since the subject understanding is necessary for thisthat could even go to total deafness and vision disorders (40%). Both visual and hearing sensory deficiencies are rare but they cause particular problems for rehabilitation and communication.

Handicap law voted in France in February 11th, 2015 [START_REF]pour l'égalité des droits et des chances, la participation et la citoyenneté des personnes handicapées[END_REF] recommends the integration of all handicapped to the school ; it supposes that they can learn. Thus, every polyhandicapped person must be able to benefit from an access to a cognitive education [START_REF] Zucman | Auprès de la personne handicapée -Une éthique de la liberté partagée[END_REF].

Polyhandicapped people generally express in a nonverbal language of their own that their entourage has to discover and understand. Therefore, the starting point is the acquisition of a communication mean (verbal or nonverbal), to express "yes/no", needs and make choices. Then, the development of personalized communication means each can be considered.

Communication is the action of establishing a relation with others to transmit information: the transmitter formulates and passes on an information; the receiver receives and decodes it. In this aim, a set of verbal and nonverbal means to exchange ideas, knowledge, information, feelings... has to be used. It is not a conscious educational practice since it exists before the appearance of the articulated language, which is supported by this set. There are several invariants which enable a better identification and understanding the multi-handicapped person communication [START_REF] Crunelle | Le polyhandicap. Aider la personne polyhandicapée à se construire et à mieux vieillir (DVD)[END_REF]: Communication in the case of polyhandicap can be passive, purely emotional, deliberate or active. We have to assume that every human being is able to communicate, to progress and to learn how to differenciate the receptive and expressive conducts. It is then a question of considering every human being capable of communication while accepting: the idea to adapt to the specificity of the multi-handicapped person, the prospect of small progressions and regressions, the important and sometimes necessary moments of latency before the person reacts.

 It is
The general motricity of a multi-handicapped child is disrupted. Therefore, it is important to inhibit the motor pathology to ease the action. The position where the child is installed is therefore an essential element to interact (BOBATH concept [START_REF] Bobath | Développement de la motricité des enfants I.M.C[END_REF]). The discovery of the environment is the basis of the language construction whatever it is (articulated speech, body movements, specific communications code). So, solicitating several means of communication will help to improve it.

The more avaible means a child has to express (gestural, verbal, visual), the more he will have the possibility of doing it. In daily life, the child evolves in a "bath of language". The polyhandicapped child also needs for this "bath of language" but it has to be more complete than for non-handicapped child so as to structure the language, whatever the difficulties faced. Therefore, a multimodal "bath of language" which associates gesture, word and image (photo, pictogram, ideogram) gives several possibilities to the multi-handicapped child to understand what surrounds him and to be understood by other people. The used syntax should not be complex but it has to convey correctly an information by several possible channels [START_REF] Cataix-Negre | Communiquer autrement. -Accompagner les personnes avec des troubles de la parole ou du langage : les communications alternatives[END_REF].

The behavior observation remains the most effective way to establish a summary of the communication capacities. Thus, the collection of information from the educational and medical teams enables to refine it. Before that, it is essential to take into account the sensory disorders for a correct observation.

The setting of an assessment grid about the personal and internal communication in the medical institution seems the the most effective way to collect the data corresponding to its project and to the goals designed for the personalized project of every child. The assessment grid must be specific to develop a coherent personalized project. The communication summary concerns [START_REF] Bartalucci | L'incidence du polyhandicap sur la communication[END_REF]:

 The auditive and visual sensory capacities. They are tested through a musical listening, a manipulation of sound toys, the use of soap bubbles, the visual pursuit of a colored object …  The reception capacities and understanding : Does the child look at his/her interlocutor? Can he/she fulfill a request ? Does he/she stop a stereotypical behavior if we ask him/her?  The global expressive attempts. They also concern the attention time of the child.

 Designation

 Symbolic gestures (spontaneous or by imitation). We have to know if the child uses them and/or if he is sensitive to their use (like signed bed songs).

 Vocal possibilities

 Verbal possibilities.

It is also necessary to plan an observation time with the children having autistic disorders with stereotypies, so as to understand their moments of appearances and if they have a particular meaning a particular relation with the situation. Thus, therapists would be able to know if these stereotypies have communication intention or not. Finally, the communication assessment grid is sometimes reassessed for the impact analysis of the proposed alternate communication method.

After this detailed assessment has been done, the communication skills can be developed. It is with this aim that several communication interfaces have been designed by our laboratory.

Examples of interfaces

Speech synthesis

This project was designed for a 14-year-old multi-handicapped teenager. He is very spastic and in a wheelchair. He has verbal capacities (he articulates some words) and vocal capacities but this requires big efforts to him (difficult articulation, salivation, important latency). His cortical blindness does not allow him to learn a successful visual designation code. Furthermore, the learning of a tactile discrimination was not considered since he showed little interest for this exercise.

He suffers from hyperacusis which makes him feel discomfort to wear an audio headset (he turns his head to remove it). Taking all these things into account, the choice has been done to make the teenager learn how to use a contactor connected to a vocal box with head movemets, so as to play various sounds or sentences. The teenager can thus communicate by movements of his head, that he is able to control thanks to the team of therapists. The contactor must be placed behind the head and it is necessary to explain him that he has to raise his head for a correct use (Fig. 1) It is based on a sound board that enables to record several messages. Several function modes are planned (Fig. 2). For example, a first click on the contactor activates 4 consecutive "wishes" messages : "go to the toilets", "rest", "watch TV", "to eat/to drink". A second click validates one of the four messages.

Various sets of messages are possible to activate depending of the situation, in terms of needs, wishes, feelings.

Improvement of the ergonomics of a speech synthesis.

The GoTalk speech synthesis enables some multi-handicapped children to communicate by pressing on a keyboard touch, each one being associated with a photo, an image or a pictogram. However, pressing precisely with the fingertip in the middle of the touch can be difficult. This is why a therapist had an idea to add a transparent plastic touch with 3 supporting points so as to be able to validate the choice wherever the fingertip is on the key. The child has thus less efforts to do to put his finger on a precise place, and the communication is eased.

Keys can be very easily removed when the purpose of a rehabilitation work can consist in a search for improvement of the positioning control of the arm, the hand, or a finger…

Rotating tray commanded by arm movement

This project was developed for a multi-handicapped teenager who possesses an athetosic movement perceived as negative since source of embarassment in daily life. Work is centered around a work on constraint and instruction. The goal is to use this problematic movement so as to turn it into something positive. He is a very agitated young man who has great difficulties to "settle". His ability of listening to other people is weak. He systematically throws the objects which are presented to him. It is difficult to identify an intention of communication with its singing exercises.

A work on objects palpation without seeing them improved its differenciation between objects that can be thrown and those who can not. It enabled to give positive value to the athetosic movement. Thus, the work on objects palpation during individual session enabled him to make its athetosic movement positive since he is now able of controlling it.

A specially designed rotating tray enables the teenager to make a choice of images using only the movement of his arm, that he can control since his athetosic gesture is perceived positively.

When the arm is moving near a proximity sensor, the tray turns and a new pictogram among those placed on it appears inside a small window. The therapist that knows well the child prepare the 4 images to place on the tray so that a choice can be done depending on his needs or pains (drinking, eating, watching TV, toothache...)

Designator wire

This equipment enables a girl suffering from polyhandicap to make choices between several images representing needs (meal, activities...) with the fingertips. It is useful when pointing out is not possible, either too constraining or non acquired (Fig. 3). Images are simply hanged on a wire with small pliers. Images and pictograms are chosen by the therapists depending on his observation of the child to help him express her wishes, needs, feelings...

Ergonomic contactor support.

Choosing or expressing a need using a contactor put on a table can be hard for some children since they can not place their hand horizontally. The contactor inclination must be then adapted to the child capacities. In this aim, slopped supports has been conceived for 5 children aged from 6 to 10. On these supports, contactors are stuck skidproof strips so that they don't move when children will press on them (Fig. 4) Hand gestures implying a designation action are therefore made easier.

Discussion on each interface

Speech synthesis limit lies in the presence of repetitive movements on the contactor that can be observed when the request or the training takes too much time. It is then hard to answer if it is caused by nervosity, impatience, or if using contactor for too long created a stereotyped movement.

In this learning phase, we can think that using a new material creates excitation. In fact, the teenager or child wants to show everybody that he can use the contactor. Nevertheless, even if its use is bad, he understood the casual link. Is it due to nervosity or impatience? Is it about a stereotypical movement engendered by the long-time use of the contactor?At this phase of learning, we can think of "the excitement" of the new material as an important reason. Indeed, this teenager is waiting to show to all that he can use his contactor.

However, the young man who uses it seems to have understood the casual link between using the contactor and an emitted sound. Furthermore, he also showed he was able to use the contactor with his wrist.

The ergonomics improvement of a speech synthesis by adding keys adapted to fingertips touch, turns out to be very positive for polyhandicapped children with imprecise hand control. Indeed, these touches facilitate the use of a GoTalk keyboard and enable these children to understand more quickly the casual link between action and sound. Thanks to their simple use, the multidisciplinary team can quickly progress in making a child learning how to use a speech synthesis.

The rotating tray commanded by arm movement enables to express various requests. The limit of this project lies in the latency between request and answer (rotating time) which raises problem to establish effective communication. The young man seems to wait the confirmation that its request is maintained by the system.

The designator wire turns out to be very effecient and enables a first learning of the designation function. It also enables the team to evaluate the child's symbolization capacity. This equipment can also be used for learning how to point out.

The use of sloped supports for contactors turns out to be particularly effective for the children in wheelchair who have a visual limitations of horizontal plan. For other children with good motor skills, these supports enable an easier use of contactors. However, the limit of this tool lies in the fact that supports are not fixed to the table and can be thrown on the ground (willingly or not).

Perspectives

Designation by ITC

The initial idea is to enable young multi-handicapped persons to indicate photos then pictograms using a computer so as "to communicate" with other people. When designating with hands is too difficult (causes: spasticité, shivers or lack of gesture control) , designation using eyes can be a good solution. We thought of using a laser pointer mounted on glasses. However, the available tools are not adapted to polyhandicap, because of material constraints (glasses move because of the wheelchair headrest and backseat. Solutions are still being investigated.

A specifically designed software able to record a laser movement, could enable polyhandicapped children to communicate, by choosing various itemps on a computer screen. The items would be much more diverse then with only paper pictograms.

Designation with joystick

Some young multi-handicapped people are learning how the use of an electric wheelchair.

Most of these wheelchairs required the use of a joystick. It seems interesting to develop a specific communication software which would enable these people to use a software tool with this interface.

Ergonomics improvement of an talking communication book

The ergonomics improvement of talking book keys is a work possibility to facilitate its use.

The current keys are small and ask for a dexterity few children suffering from polyhandicap possess.

IT adaptation to "eye tracking"

A software and hardware adaptation to communicate with eye or mouth movement could able him to express himself. The use of a device filming the eyes of the handicapped child could be an interesting tool to develop the skills of communication of this young man.

Strip for ergonomic support of contactor

Knowing the limits listed previously, it is intended to develop a belt for maintaining communication supports on the table to enable the use for the biggest number possible of children.

Serious Games

We also work on conceiving serious games adapted to polyhandicapped and/or autistic children. Serious games are software including an amusing aspect that enables to deliver a message (educational, marketing, etc.) and/or to estimate the user by the interactions whom he will have with the game. Applications of serious games exist in various fields [START_REF] Alvarez | Introduction aux Serious Games[END_REF], particularly health and handicap [START_REF] Hocine | Adaptation in serious games for upper-limb rehabilitation: an approach to improve training outcomes[END_REF] [START_REF] Holden | Virtual Environments for Motor Rehabilitation: Review[END_REF].

The first game we are currently developing -in the continuity of our acquired experiencemakes children walk in a forest where they will find objects to be collected. The psychiatrist accompanying the children can get relevant information from their chosen items, i.e. knowing their preferences, according to the nature and the characteristics of the selected items. The psychiatrist could use them to improve the communication with the children.

Conclusion

Our work aims at showing that whatever communication method is chosen, it is essential to adapt the existing material or to create it so that the polyhandicapped child can appropriate and uses it easily. Multidisciplinary work is essential to the sustainability of communication method. The multidisciplinarity will shed light on the chosen method and the possible evolution of its use. We were able to show that polyhandicap requires techniques specialized in the learning of relation and communication means. It also requires to be creative and imaginative.

The starting point of each development work must be made of the expression of needs and choice. The material could be made after evaluating competences and communication capacities. It is also necessary to take into account the specific answer time of polyhandicapped children to a request.

Finally, partnerships with various professionals must be done so as to improve commuication techniques. Competencies of each member of the team are indeed sometimes unknown, and requires to be sollicitated for the whole project benefit.

  a multimodal and most of the time nonverbal communication,  It is specific in shape and nature,  It does not relate to any communication standard; the interactions are thus not conventional  It requires an analytical precise evaluation and raises the problem of behavior interpretation.

Fig. 1 .

 1 Fig. 1. Speech synthesis commanded by movements of head.

Fig. 2 .

 2 Fig. 2. Speech synthesis and contactor.

Fig. 3 .

 3 Fig. 3. Designator wire

Fig. 4 .

 4 Fig. 4. Slopped contactor support


Marie Poitrimolt

Mohammed Cheikh
email: mcheikh@univtlse2.fr

Gérard Bernhart

Vincent Velay

Ge ´rard Bernhart

Characterisation of the transverse mechanical properties of carbon/carbon composites by spherical indentation

teaching and research institutions in France or abroad, or from public or private research centers.

Introduction

Carbon/Carbon (C/C) composites have been under develop ment since the 1960s as thermo structural materials for high temperature applications such as in the case of aeronautical braking, motor sports, nozzles, etc. Their moderate density (less than 2), thermal properties such as a low coefficient of thermal expansion, and a large heat capacity at high temper ature (2.5 times higher than that of steel) as well as good mechanical properties up to 2000 °C, make them indeed good materials for hot working structural elements. This work is a part of a study on C/C composites for brake discs against steel discs in a lubricated environment for aerospace applications. Its aim is the characterisation of C/C composites in the transverse direction to the plane of friction using the indentation technique. In a braking configuration, the brake discs are highly stressed in the transverse direction. With a very low coefficient of friction and particularly in a lubricated environment, the friction force is provided by increasing the load in the normal direction to the plane of friction. For sizing the C/C discs to support these load levels, accurate mechanical characterisation in the transverse direc tion is required.

In the literature, studies of C/C composites for brake appli cations are typically oriented towards the study of the friction behaviour of these materials. Few studies have addressed the characterisation of these composites in transverse compres sion. For example, one can cite the works of Davies and Rawlings [START_REF] Davies | Mechanical properties in compression of low density carbon/carbon composites[END_REF] and Douarche et al. [START_REF] Douarche | Relations between x ray tomography, density and mechanical properties in carbon carbon composites[END_REF] on the characterisation of these materials in compression. The behaviour of these materials in compression depends heavily on the specimen's geometry and particularly its thickness [START_REF] Davies | Mechanical properties in compression of low density carbon/carbon composites[END_REF]. To remedy the Figeac) and S. Tovar (EMAC Albi) for the manufacturing and the preparation of the specimens used in the experimental section of this work.


Dr Xiaozhou Ma

Dr Elizaveta A Suturina

Siddhartha De

Philippe Négrier

Mathieu Rouzières

Rodolphe Clérac
email: clerac@crppbordeaux.cnrs.fr

Pierre Dechambenoit
email: dechambenoit@crppbordeaux.cnrs.fr

M Rouzires

Dr D R R Clørac

Dr P Nøgrier

A Redox-Active Bridging Ligand to Promote Spin Delocalization, High-Spin Complexes, and Magnetic Multi-Switchability

Keywords: molecular magnetism, multiswitchability, non innocent ligands, r adicals, spin delocalization

niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Single-Molecule Magnets

AR edox-ActiveB ridgingL igand to PromoteSpin Delocalization, High-Spin Complexes,and Magnetic Multi-Switchability Xiaozhou Ma, Elizaveta A. Suturina, Siddhartha De,P hilippe NØgrier,Mathieu Rouzires, Rodolphe ClØrac,* and Pierre Dechambenoit* Abstract: Ad inuclear Co II complex, [Co 2 (tphz)(tpy) 2 ] n+ (n = 4, 3o r2 ;t phz:t etrapyridophenazine;t py :t erpyridine), has been assembled using the redox active and strongly complex ing tphz bridging ligand. The magnetic properties of this complex can be tuned from spin crossover with T 1/2 % 470 K for the pristine compound (n = 4) to single molecule magnet with an S T = 5/2 spin ground state when once reduced (n = 3) to finally ad iamagnetic species when twice reduced (n = 2). The two successive and reversible reductions are concomitant with an increase of the spin delocalization within the complex, promoting remarkably large magnetic exchange couplings and high spin species even at room temperature.

One of the most attractive features of molecule based materials is the ability to fine tune and control their physical properties by as uitable choice of the molecular compo nents. [1] In magnetism, this ability is of great interest as the magnetic properties usually result from cooperative effects between the spin carriers.T he choice of the linker between spin carriers is therefore crucial as it mediates the commu nication/interactions between them. Using redox active bridging ligands is thus particularly appealing as they are able to favor electronic conductivity,p rovide multistability, and allow ac ertain tuning of the magnetic properties by simple oxidation or reduction. [2] In particular, the isolation of bridging ligands in their stable radical forms can be seen as the key to design new materials with strong magnetic exchange coupling,asthe radical linker acts as avery efficient magnetic relay between the metallic spin carriers. [3] This strategy was successfully used to synthesize single molecule magnets (SMMs), single chain magnets with high blocking temperatures, [3a c,4] as well as the first room temperature molecule based magnet. [5] In our quest to design an ideal redox active bridging ligand, tetrapyridophenazine (tphz) has been chosen (Sup porting Information, Scheme S1). This ligand has been reported to be redox active when coordinated to Ru metal ions, [6] with two successive well separated (by 0.6 V) one electron reduction processes.T he reduced forms were not further investigated and, to the best of our knowledge,t his ligand has never been involved in magnetically interesting materials.The strong coordination ability (thanks to achelat ing bis(tridentate) coordination mode), the planarity and the extended p system of tphz are also expected to support alarge delocalization of the unpaired electron when reduced once, providing an excellent radical linker candidate for the design of strongly coupled magnetic architectures. [3e] To probe this promising idea, prototype dinuclear complexes have been synthesized by reaction of the bridging tphz ligand with paramagnetic metal centers capped by terpyridine (tpy) blocking ligands.H erein, we report an ovel redox active dinuclear Co II system, [Co 2 (tphz)(tpy) 2 ](PF 6 ) x (x = 4, 3, or 2), displaying an increasing spin delocalization upon two succes sive reduction processes,r esulting in the promotion of remarkably large magnetic couplings,s uch that the S T = 5/2 and S T = 0g round states of the mono and twice reduced species remain well isolated from excited states even at room temperature.

[Co 2 (tphz)(tpy) 2 ](PF 6 ) 4 •3 CH 3 CN (1)w as prepared by reacting Co(tpy)Cl 2 [7] with tphz in the presence of TlPF 6 in acetonitrile.Subsequent diffusion of diethyl ether vapor into this dark red solution yields needle shaped orange crystals of 1 (see the Supporting Information). This compound was characterized by single crystal X ray diffraction at 120 K (Figure 1; Supporting Information, Table S1), confirming the envisioned structure with two crystallographically equivalent Co(tpy) 2+ units connected by tphz. Thecomplex 1 crystallizes in the C2/c space group with at wo fold axis passing through its center perpendicularly to the mean plane of the tphz ligand. Each Co ions reside in an octahedral environment involving three nitrogen atoms from the bridging ligand and another three nitrogen atoms from capping terpyridine.T he Co Nb ond distances between the metal and tpy (Co N4,N5,N6) range from 1.87 to 1.99 ,indicating aCo II center in its low spin (LS) state. [START_REF] England | [END_REF] TheC o N pyz bond distance (Co N2) between Co and tphz is 1.94 while the other two Co N py distances (Co N1 and Co N3) are significantly longer due to the rigidity of the bridging ligand (Table 1).

To investigate the redox properties of this prototype dinuclear complex, cyclic voltammetry of 1 was performed in acetonitrile,r evealing four redox processes,c entered at 0.34 V, 1.04 V, 1.77 Vand 1.93 Vv s. Fc + /Fc (Figure 2; Supporting Information, Figure S3). Therest potential is close to 0V ,i ndicating the presence of only reduction processes, each of them involving one electron. [START_REF]Cyclic voltammograms of 1, 2,and 3 are identical[END_REF] These potentials are very close to what has been reported for the Ru analogue, [6b] suggesting that the redox processes are mainly centered on the ligands,w hich will be further confirmed by crystal structure analysis and DFT calculations (see below). The first two signals correspond to the reduction of the central tphz whereas those at about 2Vcorrespond to those of the tpy ligands.T he dissymmetry of the most cathodic signal is very diffusion dependent and was not further investigated. Thepotentials of the three first reduction processes are well separated (by 0.7 V), indicating that the mono and doubly reduced species are particularly stable.Itisalso remarkable to observe the presence of two peaks for the tpy ligands, indicating as ignificant electronic coupling through the [Co (tphz)Co] moiety.

Based on these redox properties, 1 was reacted with as light excess of one,t wo,a nd four equivalents of as trong reductant, KC 8 ,a ffording after recrystallization the once, twice,and four times reduced analogues as [Co 2 (tphz)(tpy 4). Owing to the extreme instability of 4,o nly its single crystal X ray analysis is reported in the following.

) 2 ] (PF 6 ) 3 •2 CH 3 CN (2), [Co 2 (tphz)(tpy) 2 ](PF 6 ) 2 •2 CH 3 CN (3), and [Co 2 (tphz)(tpy) 2 ]•2 THF (
Theo verall molecular structure of the dinuclear com plexes in 2, 3,a nd 4 is similar to 1 (Supporting Information, Figure S1, Table S1);that is,each Co center is surrounded by six nitrogen atoms from tpy and tphz ligands,e ach Co being equivalent by symmetry as ac onsequence of an inversion center or two fold axes.E xamination of the bond length reveals however noticeable differences and features (Table 1; Supporting Information, Table S2). Thea verage Co Nd is tances between Co and tpy ligands are 2.12 in 2 and 3, consistent with ahigh spin (HS) Co II center. In 4,this average bond distance is 1.96 and ac lear Jahn Teller distortion is observed along the N1 Co N3 axis,s imilar to 1 and what is expected for al ow spin (LS) state. [START_REF] England | [END_REF] In these complexes,t he spin state assignment of the Co sites is also confirmed by DFT (B3LYP/def2 TZVP) calculations,w hich indicate aL Ss tate significantly lower in energy than the HS state in 1 and 4,and contrariwise in 2 and 3 (Supporting Information, Figure S15). This is further supported by ligand field analysis and by the complete active space self consistent field method (CASSCF) carried out in ORCA 4.0, [10] which shows that the cobalt centers in 1 and 4 have larger ligand field splitting than in 2 and 3,e xplaining therefore their LS versus HS preferences (Supporting Information, Figure S16). Thepossibility to be in presence of Co III in 1 and Co I in 3 or 4 was also considered, but excluded after combined analysis of the magnetic suscepti bility,c rystal structure,a nd DFT data. Upon reduction, the evolution of C Na nd C Cb ond distances in tpy and tphz ligands (Table 1; Supporting Information, Table S2) is also confirming the previous assignment of the reduction process es.W hereas the two first reductions do not affect the bond distances in the tpy capping ligands,asignificant elongation of their C Nb ond distances occurs in 4,sign of their reduction in the two most cathodic reduction processes (Supporting Information, Table S2). One can also notice that the two first processes are centered on the pyrazine part of tphz bridging ligand with as ignificant elongation of pyrazine C Nb onds and al arge increase of N2•••N2' distance,w hereas the bond distances of the pyridine moieties in tphz and tpy remain almost unchanged (Table 1). While the Co N py distances (Co N1,N3) remain rather long owing to the rigidity of tphz [a] 1.405( 8) 1.397( 8) 1.381(6) 1.378(8) C N(pyz) [a,b] 1.331( 8 [a] pyz pyrazine part of tphz. [b] Average distance. in this series of complexes,a nother interesting structural feature is the remarkably short Co N pyz (Co N2) bond distance in 2 (1.97 )a nd even more in 3 (1.92 ;T able 1). These bond distances are much shorter than what has been reported for HS Co II centers with similar tetrakis(2 pyridyl) pyrazine (tppz) ligands. [11] In the present case,the persistently short Co N2 bond length upon reduction is likely ac onse quence of the enhanced electrostatic interactions upon successive reductions,w hich compensate the expected bond lengthening owing to the spin state switching.T hose short bond distances also suggest ap articularly good overlap between the Co and tphz orbitals,w hich could enable stronger magnetic exchange coupling than in the tppz based systems,w hich are already known to mediate significantly strong magnetic coupling. [3d, 11, 12] To evaluate and compare the strength of the magnetic coupling in this family of complexes,d cm agnetic suscepti bility measurements were performed for 1, 2,a nd 3 under a0.1 Tapplied field. For 1,the cT product reaches aplateau at about 100 200 Kw ith av alue of 0.85 cm 3 Kmol À1 ,i na gree ment with two isolated LS Co II centers with g = 2.13(5) (Figure 3). Upon cooling below 100 K, the cT value decreases down to 0.04 cm 3 Kmol À1 at 1.85 K, which can be ascribed to the presence of an antiferromagnetic coupling between the two S = 1/2 Co II magnetic centers.A lthough weak, this exchange constant of 12.7(3) K( green line in Figure 3; with g = 2.17( 5)) [START_REF]were estimated by fitting the experimental data to the susceptibility calculated from the van Vleck equation in the weak fieldapproximation relative to the following isotropic spin Hamiltonian: H ˆ2 J(S ˆCo1 S ˆCo2 )[END_REF] is remarkably larger than what is usually observed through diamagnetic pyrazine bridging ligand. [3g, 11d] Above 200 K, the compound undergoes as pin crossover (SCO) behavior. The cT value at 400 K( 1.72 cm 3 Kmol À1 ) highlights an incomplete S = 1/2 (LS) to 3/2 (HS) thermal conversion for each cobalt ion, [START_REF] Gazda | [END_REF] which was fitted to an ideal solution model (red line in Figure 3) assuming ac onstant g value of 2.18 and giving rise to T 1/2 % 467( 5) Kw ith an associated enthalpy variation of 27( 2) kJ mol À1 . [START_REF]for pure LS and HS species assuming a g value of 2.18, R the ideal gas constant and DH the associatedenthalpy variation[END_REF][START_REF] Atkins | Physical Chemistry[END_REF] Upon further cooling, the magnetic properties are nearly reversible but the partial loss of interstitial solvent molecules around 400 Kp revents obtaining the exact same SCO behavior (Supporting Information, Figure S8).

Forthe monoreduced compound 2,the cT product found at room temperature is 6.3 cm 3 Kmol À1 ,which is much larger than the expected spin only value for two magnetically isolated S = 3/2 Co II and one S = 1/2 radical (Figure 3). This result is however more consistent with an S T = 5/2 ground state (with g = 2.40( 5)) expected in presence of an extremely large exchange coupling between Co II magnetic centers and the bridging tphz À C radical spin. The cT values remain almost constant in the 100 300 Kt emperature range also indicating that the S T = 5/2 ground state is well isolated from excited states,asconfirmed by DFT calculations that situate the first excited quartet state at about 500 Ka bove (Supporting Information, Figure S18). Thel arge magnitude of the J Co tphz C interactions and the resulting temperature independ ence of the cT product above 100 Kp reclude any exact quantification of J Co tphz C

,n evertheless it was roughly esti mated to be at least 500 Kb ys imulating the experimental susceptibility data using at hree spins model with PHI. [START_REF] Was | roughly estimatedbyfitting the data using the following spin Hamiltonian: H ˆ2 JS ˆrad (S ˆCo1 + S ˆCo2 ). Thes light increase of the cT product between2 80 and 300 Ki st he onset of the solvent loss,which precludes fully reproducible studies at higher temperatures[END_REF][START_REF] Chilton | [END_REF] This approximated value constitutes unequivocally one of the highest interaction reported to date [3] and is in good agree ment with DFT results ( 509 K). Note that below 300 K, the compound is better described as asingle S T = 5/2 macro spin, with as pin density delocalized on the Co centers,i ts coordination sphere and the whole pyrazine part of the tphz ligand (Figure 4). Them agnetic anisotropy,r evealed by the decrease of the cT product below 40 K, was estimated to be D/k B %+ 27.6(9) K, [START_REF] Chilton | [END_REF][START_REF]D were estimated by fitting simultaneously the cT vs. T and M vs. H data with the Phi software using the following spin Hamiltonian: H ˆDS ˆ2[END_REF] in very good agreement with the NEVPT2 results (D/k B =+27 K).

When further reducing the complex, magnetic suscepti bility measurements of the resulting compound 3 reveal ac ontinuous increasing of the cT product from 0.07 cm 3 Kmol À1 at 1.8 Kto2.01 cm 3 Kmol À1 at 400 Kwithout Figure 3. Temperaturedependence of the cT product for 1, 2,and 3 at 0.1 T( black, purple, and blue circles, respectively). The lines represent the best fits as discussedi nthe text. [START_REF]were estimated by fitting the experimental data to the susceptibility calculated from the van Vleck equation in the weak fieldapproximation relative to the following isotropic spin Hamiltonian: H ˆ2 J(S ˆCo1 S ˆCo2 )[END_REF][START_REF]for pure LS and HS species assuming a g value of 2.18, R the ideal gas constant and DH the associatedenthalpy variation[END_REF][START_REF]D were estimated by fitting simultaneously the cT vs. T and M vs. H data with the Phi software using the following spin Hamiltonian: H ˆDS ˆ2[END_REF] Inset:m agnetization versus field curves for 2 below 8K. reaching aplateau in this temperature range (Figure 3). This thermal behavior is consistent with astrong antiferromagnetic coupling between the two HS Co II magnetic centers leading to asinglet ground state.Indeed, the best fit of the cT vs. T data gives rise to J/k B = 74( 5) K( with g = 2.03( 5);b lue line in Figure 3), amuch larger coupling than what one could initially expect through af ormal diamagnetic ligand. As ac onse quence of this large coupling,the singlet ground state is quite well isolated from the excited states,a sc learly supported by DFT calculations (J/k B = 137 K, see below). This result is also observed in solution, as confirmed by 1 HNMR at room temperature,w hich shows only slightly paramagnetically shifted resonance peaks of tpy and tphz (between 7.4 8.7 and 8.3 11.7 ppm, respectively;Supporting Information, Fig ure S6), in marked contrast to 1 and 2 (Supporting Informa tion, Figures S4,S5). Thee stimation of the magnetic suscept ibility in solution by Evansmethod gives rise to acomparable cT value at 300 K( 2.48( 8) cm 3 Kmol À1 )t han in solid state (1.77(8) cm 3 Kmol À1 ;s ee details in the Supporting Informa tion).

Ac susceptibility measurements were also performed to probe the magnetization dynamics of these complexes and in particular the possible single molecule magnet (SMM) prop erties. [START_REF] Murrie | [END_REF] Frequency and temperature dependent ac signals were revealed under as mall applied dc field (600 Oe; Supporting Information, Figures S9 S12) only for 2.T o probe the effect of the applied dc field on the slow relaxation of magnetization, the characteristic time, t,w as extracted by fitting both variable field and temperature ac susceptibility data with the generalized Debye model. Thebest fit of t(T,H) was obtained considering only Direct and Raman relaxation mechanisms (Supporting Information, Figure S13), which are thus at the origin of the SMM properties of 2. [START_REF]Ther elation t 1 t 1 Raman + t 1 Direct C 1þB1H 2 1þB2H 2 T n + ATH 4 was used to fit simultaneously the t vs. T and t vs. H data[END_REF]22] To explain the large intramolecular magnetic interaction and the resulting well isolated ground state of [Co 2 (tphz) (tpy) 2 ] 3+ and [Co 2 (tphz)(tpy) 2 ] 2+ in 2 and 3 respectively, comprehensive DFT studies were performed (see details in the Supporting Information). Forb oth complexes,t he spin density calculated with the broken symmetry solution shows as ignificant spin delocalization on the p system of the tphz bridging ligand as depicted on Figure 4. Indeed, as shown by ab initio ligand field analysis (Supporting Information, Fig ure S16), unpaired electrons of the HS Co II 4; Supporting Information, Figures S19 andS20, Table S4), and thus as trong magnetic exchange.T his spin delocalization through the p system is even slightly larger in 3 than in 2 (14 vs.1 0%;S upporting Information, Table S4). These orbital considerations are often overlooked for the design of molecule based magnets except in the case of the cyanide bridge for which this approach has been extensively discussed. [23] As ag eneral synthetic strategy,t he present results illustrate the importance of using metal ions with singly occupied d xy orbital, to design highly magnetically coupled systems with aromatic bridging ligands.T he large orbital delocalization is also supported experimentally by ab road absorption band in the NIR region at 782 nm for 2, and 1250 nm for 3 (Supporting Information, Figure S7), indicative of an unusually large electronic delocalization for non mixed valence systems.This ability of the bridging ligand to mediate as trong communication between the metal centers results therefore from ar emarkably strong metal ligand coordination (as illustrated by the unusually short Co N2 bond) intrinsically linked to as trong overlap of da nd p orbitals and an extended delocalization through the p system.

In summary,anew multi switchable complex has been rationally assembled using ar edox active and strongly com plexing bridging ligand. By simple oxidation/reduction, its magnetic properties can be tuned from as pin crossover complex, to as ingle molecule magnet with an S T = 5/2 spin ground state (when once reduced) and to diamagnetic species when twice reduced. This work illustrates experimentally and theoretically how successive redox processes can increase the spin delocalization, and thus promote ad ramatic enhance ment of the intramolecular magnetic coupling through ab ridging ligand, not only in its radical form. This general synthetic approach should help for the intentional design of new high spin complexes and SMMs,b ut it could also be extended to systems with higher nuclearities and dimension alities,f or example to obtain high temperature molecule based magnets.

Figure 1 .

 1 Figure 1. Crystal structure of [Co 2 (tphz)(tpy) 2 ]4+ in 1 at 120 K. Ellip soids are set at 50 %p robability;h ydrogen atoms, solvent molecules, and counteranionsare omitted for clarity.[24]

Figure 2 .

 2 Figure 2. Cyclic voltammogramofasolution of 1 in CH 3 CN at a0.1 Vs 1 scan rate, with 0.1 m (n Bu 4 N)PF 6 as supportingelectrolyte.

Figure 4 .

 4 Figure 4. View of the computeds pin density of the broken symmetry solution for the complexesin1, 2,a nd 3.C olors represent different signs of the spin density.

Table 1 :

 1 Selected bond distances []i n1 4 complexes.

		1234
	Co N1	2.353(6)	2.344(6)	2.396(4)	2.650(4)
	Co N2	1.936(5)	1.970(5)	1.923(3)	1.976(5)
	Co N3	2.286(6)	2.320(6)	2.269(4)	2.144(4)
	Co N4	1.991(6)	2.129(6)	2.152(3)	2.001(4)
	Co N5	1.875(5)	2.089(5)	2.069(3)	1.885(4)
	Co N6	1.947(6)	2.148(6)	2.128(3)	2.008(4)
	C C(pyz)

  are localized on d x 2 Ày 2 ,d z 2 ,and d xy orbitals.Whereas the d x 2 Ày 2 and d z 2 orbitals overlap with nitrogen s orbitals,t he d xy orbitals interact strongly with p orbitals of tphz bridging ligand, providing ap rivileged channel for significant spin delocalization (Figure

Acknowledgements

This work was supported by the ANR (ANR 16 CE29 0001 01, Active Magnet project), the University of Bordeaux, the RØgion Nouvelle Aquitaine,the CNRS,the MOLSPIN COST action CA15128 and the CSC for the PhD funding of X.M. E.A.S.t hanks EPSRC for support (EP/N006895/1), the IRIDIS High Performance Computing Facility and associated services at the University of Southampton and the RSC for atravel grant. Theauthors thank also D. Woodruff,J . L. Liu, A. Mondal, and S. Exiga for their assistance and fruitful discussions as well as the GdR MCM 2:M agnØtisme et Commutation MolØculaires.

Conflict of interest

Theauthors declare no conflict of interest.


Winati Nurhayu

Sarah Nila

Michel Raymond

Bambang Suryobroto

Pakos, E. E G Mitsionis

Are right-and left-handedness relevant as general categories in a non-industrialized country?

Whether right-and left-handedness are defined as a function of individual tasks or represent general categories across tasks has been long debated. However, the literature on handedness primarily concerns industrialized societies in which manual work has been extensively automated, and the majority of individuals in those countries do not use their arms and hands intensively for highly specialized tasks on an everyday basis. Thus, the question remains whether results from those countries regarding handedness are transferable to countries where the majority of individuals are still exploiting their lateralized skills. Here, we sampled 506 individuals from 143 locations on the islands of Flores and Adonara, Indonesia, to assess their hand preference for and hand performance on several tasks in order to evaluate, in a non-industrialized country, the level of manual specialization and the relevance of right-or left-handedness as general categories. Generalizeddeclared handedness was consistent with task-declared handedness across 10 specific tasks and with a measure of strength and a measure of skilfulness, suggesting that general handedness is a valid concept. This hand specialization for tasks is discussed in the context of intense and daily tool use in this agricultural society.

Introduction

Manual specialization, when the same hand is used for different unimanual tasks, describes handedness at the individual level (Marchant & McGrew, 2013). When manual specialization extends to most tasks, an individual is either right-or left-handed, and a generalized handedness is a meaningful concept. When an individual uses one hand for a task and the other hand for another task (referred to as ambidexterity across tasks, or ambilaterality), the concept of generalized handedness weakens. There is an abundance of literature concerning handedness in contemporary humans (McManus, 1996;Llaurens, Raymond, & Faurie, 2009), and two contrasting results are emerging.

First, there are no two clear categories such as left-and right-handers: for a given manual action, each individual shows a preference for the use of one hand, and it is not always the same hand for two different actions [START_REF] Salmaso | Problems in the assessment of hand preference[END_REF]. This suggests that right-or left-handers are not general categories, but rather are defined as a function of the tasks. This justifies the use of continuous index across various tasks to quantitatively measure handedness, such as the classical Edinburgh Handedness Inventory [START_REF] Oldfield | The assessment and analysis of handedness: The Edinburgh Inventory[END_REF]. However, much of the research is concerned primarily with industrialized populations (Marchant, McGrew, & EiblEibesfeldt, 1995;[START_REF] Cavanagh | Hadza handedness: lateralized behaviors in a contemporary hunter-gatherer population[END_REF]. This is a pivotal point, as manual work, particularly in agriculture, has been extensively automated in industrialized countries. There are still some specific professional activities requiring high manual specialization, such as surgery, butchery, stonemasonry, hairdressing, some sports, and others. However, the majority of individuals in those countries, comparatively to non-industrialized countries, are probably not using their arms and hands intensively on highly specialized tasks on an everyday basis (usage of keys, mouse, comb, airdryer, phone etc. does not require a very high and intense manual specialization). This general decrease of specialized and demanding manual tasks in the daily life of modern societies probably explains the secular decline of handgrip strength, and more generally of muscular strength components, observed during the last century in e.g. US, Canada, Denmark, and Spain (Malina, 2004;[START_REF] Silverman | The secular trend for grip strength in Canada and the United States[END_REF][START_REF] Moliner-Urdiales | Secular trends in health-related physical fitness in Spanish adolescents: The AVENA and HELENA Studies[END_REF].

Second, when the tasks considered are highly skilled and complex, and the individuals tested are specialized in these tasks, there is a very strong correlation between the different tasks [START_REF] Bryden | Measuring handedness with questionnaires[END_REF][START_REF] Wood | Handedness in 'fast ball' sports: Do lefthanders have an innate advantage[END_REF]Marchant & McGrew, 1998), suggesting right-and lefthandedness are useful categories in this context. Interestingly, when asked whether they consider themselves right-or left-handed, many people from western countries respond according to the hand they use to write, as writing and related activities are probably now the most common unimanual task considered as skilled and complex.

Thus the question remains on the level of hand specialisation in non-industrial countries. If mechanisation, by massively decreasing the need for intense manual work, has decreased manual specialisation, then a higher level of hand specialisation is expected on those countries not affected by the process of extended mechanisation. On the opposite, if mechanisation does not affect the level of hand specialisation, no difference are expected when comparing industrialised and nonindustrialized countries. Comparison with studies measuring handedness in traditional or nonindustrialized society is not straightforward, as the various measures of handedness developed in modern countries are not always useful for a cross cultural analysis. Questionnaires are often unsuitable (such as the classical Edinburgh Handedness Inventory which considers non-universal tasks such as tooth-brushing, holding a golf club, or using a broom, see [START_REF] Oldfield | The assessment and analysis of handedness: The Edinburgh Inventory[END_REF]), unreliable as indicators, and/or biased toward Western cultural frameworks (Marchant, McGrew, & EiblEibesfeldt, 1995;[START_REF] Steele | Stone Knapping: The Necessary Conditions for a Uniquely Hominin Behaviour[END_REF][START_REF] Cochet | Evolutionary origins of human handedness: evaluating contrasting hypotheses[END_REF]. Additionally, to our knowledge, only seven publications on handedness from traditional populations have been published (excluding studies focused on subadults), corresponding to 12 studies on 11 populations (Table 1). Manual specialization could not be evaluated in these populations, because only one task was studied (5 cases), or individual data for more than one task were either not recorded or not reported (6 cases). The only remaining study [START_REF] Connolly | The measurement of handedness: A cross-cultural comparison of samples from England and Papua New Guinea[END_REF], performed in the Western Highlands of Papua New Guinea, used solicited performance from people seated on the ground in the focal centre in the villages, thus in the presence of a social audience (plus a foreign scientist), thus introducing social interferences, as described in the authors: "there was a certain shyness and reluctance made all the more significant by the inevitable crowd of spectators who were almost always in attendance. The spectators were invariably jolly, laughing and joking amongst themselves about the activities and the person performing the tests. One very striking feature was the dramatic change in demeanour when a spectator was persuaded to become a subject; the laughing and interactions with others stopped and an air of focused concentration took over". In addition, the solicited task performance included manipulation of unknown items, such matches, pencils, spoon, playing cards, etc., thus questioning the ecological validity of the data [START_REF] Cochet | Evolutionary origins of human handedness: evaluating contrasting hypotheses[END_REF]. In conclusion, to our knowledge, there are no sufficient published data from which to evaluate the level of manual specialization (within subjects, across tasks) in non-industrialized societies. Thus, the question remains regarding whether the results for handedness from industrialized countries are transferable to populations where the majority of individuals are still exploiting their lateralized skills.

Here, we sampled individuals born on the island of Flores, Indonesia, to assess their hand preference for or hand performance on several tasks to evaluate, in a non-industrialized country, the level of manual specialization and the relevance of right-or left-handedness as general categories.

Materials and Methods

Participants

The study was performed in January 2015 and January 2016 on the island of Flores (and the small and adjacent island of Adonara), Indonesia. A total of 143 locations were sampled from most of the regencies (Kabupaten) on the islands. Locally, groups of at least 3 individuals were targeted, often resulting in a larger sample due an unavoidable social snowballing effects. Most of the time the people in groups outside homes were males, and the social snowbowling effect concerned mainly males, resulting in a male biased sample. Sampling was performed independently to the proportion of left-hander, although the snowballing effect resulted in a higher proportion of left-handers (left-handers neighbours were sometimes solicited by participants as soon as the purpose of the study was disclosed). These non-randomly sampled participants were kept in the final sample, as no population-level inferences were sought. At the beginning of each interview, the participants were informed of the general aim of the study, the type of data collected and that the data would only be used anonymously for a scientific purpose. A written voluntary agreement was obtained prior data collection. The interviews were conducted in the Bahasa Indonesia language in the presence of one Indonesian researcher. No financial incentive was provided.

Handedness measures

We designated interviewed subjects as focal respondents. They were asked whether they were overall left-or right-handed. These focal individuals also provided hand preference information for their close kin and other family members (reported elsewhere). Next they were asked about their specific hand preference (right, left, both) for ten tasks based on [START_REF] Rife | Handedness, with special reference to twins[END_REF]: ball throwing, racquet holding during badminton (a popular game in Indonesia), the use of three distinct large tools (knife/machete, hammer, saw), marble play, writing, and the use of three distinct small tools (spoon, scissors, needle). According to the anatomical and functional analysis by [START_REF] Napier | The prehensile movements of the human hand[END_REF], these tasks are further classified as requiring either a power grip (the object is held as if in a clamp between the flexed fingers and the palm, and counter pressure is applied by the thumb lying more or less in the plane of the palm), corresponding to the first five tasks, or precision grip (the object is pinched between the flexor aspects of the fingers and that of the opposing thumb), corresponding to last five tasks. As handedness measured from questionnaires are known to be not fully correlated with performance (e.g. [START_REF] Raczkowski | Reliability and validity of some handedness questionnaire items[END_REF][START_REF] Cavill | Development of handedness: Comparison of questionnaire and performance-based measures of preference[END_REF], behavioural cross-validation was sought and two measures of hand performance were recorded. The writing-declared handedness was cross-checked by recording the hand used to sign the voluntary agreement sheet: in all cases recorded (N = 324), an exact concordance with writing-declared handedness was observed. Handedness could sometime be observed during an unsolicited behaviour (e.g., after the interview an individual resumed his manual work using a tool): in all cases (N = 14), an exact concordance with the declared handedness for the corresponding action was observed. Hand-grip strength was measured using a hand dynamometre "Grip-D", T.K.K 5401 series (Takei Scientific Instrument, Niigata, Japan). The mean of four consecutive grips was recorded for each hand (G R and G L ), and the relative hand difference was computed as (G R -G L )/ (G R +G L ). Which hand (R or L) was used as the starting hand for this measure was recorded as a potential confounding variable. Hand skill was measured using a peg-moving task. The respondents were asked to move the pegs with tweezers, along a line of holes, from the first hole to the next hole one by one until the pegs were moved to the last hole (five steps for each line, three lines concerned, see Figure S1). This movement was performed with one hand and was repeated 3 times for each hand, alternating between hands. The mean of three trials was computed for each hand (S R and S L ), and the relative hand difference was computed as (S R -S L )/(S R +S L ). The starting hand was also recorded.

Statistical analyses

The influence of sex and age on handedness was evaluated using logistic regression. The Influence of sex, handedness, their interaction, and confounding variables (age, starting hand of the measure) on relative handgrip or relative hand skill was evaluated using linear regression. The concordance of handedness over the tasks was measured and tested using Fleiss's Kappa for categorical data [START_REF] Fleiss | Measuring nominal scale agreement among many raters[END_REF], via the R package irr. The ability of each handedness variable, or of a group of handedness variables, to correctly assign the generalized-declared handedness of an individual was evaluated using linear discriminant analysis. The R package MASS (version 7.3-44) was used, with the option leave-one-out cross-validation, for the results (classes and posterior probabilities). The resulting percentage of correct classification was compared to the percentage obtained under random assignment, i.e. the percentage of the most frequent handedness class (RH, 79.2%). Exact confidence intervals of binomial proportions were computed using the R package binom (version 1.1-1). All analyses were performed using R version 3.3.0.

Results

Sample description

A total of 506 individuals were directly interviewed (focal), corresponding to 145 females and 361 males. Individuals (N = 26) not born on Flores or Adonara were removed from the sample, resulting in a final sample of 480 focal individuals (Table S1): 135 females and 345 males. For the age distribution (from 13.3 to 76.4 years old), the mean was 37.3 years (34.8 years for women and 38.4 years for men), the median was 36.0 years (33.6 years for women and 37.3 years for men) and the standard deviation was 13.7 years (13.1 for women and 13.8 for men).

Declared hand preference

A total of 478 individuals declared their general handedness: 101 left-handed (31 females and 70 males) and 377 right-handed (104 females and 273 males), resulting in an overall sample frequency of 21.1% left-handers, see Table 2 (no population inference was possible, due to an oversampling of left-handers). Generalized-declared handedness was used as a response variable in a binomial regression to assess the influence of sex and age. The males and females did not differ significantly (P = 0.82) for the declared hand preferred. Generalized-declared right-handedness was significantly (P = 0.0082) associated with older age, with a 0.024 increase of linear unit (i.e., log of odd ratio) for each additional year.

A total of 480 individuals declared their handedness for up to 10 tasks, resulting in a total of 4,737 reports. From these reports, 15 (or 0.32%) were declared as ambidextrous. For any given task, the frequency of ambidextrous reports was between 0 (for 4 tasks) and 0.8%. Due to their low frequency, those ambidextrous reports were further coded as left-handed. Overall, the sample percentage of task-declared left-handedness ranged from 11.0% to 21.7% (Table 2). A total of 472 individuals reported their hand preference for all ten tasks. Concordance over the 10 tasks was significant (Fleiss's Kappa = 0.884, z = 129, P < 10 -4 ), and was even stronger when writing handedness, which is prone to cultural influences, was omitted (Fleiss's Kappa = 0.935, z = 122, P < 10 -4 ). Generalized-declared handedness was significantly correlated with each of the 10 tasks-declared handedness (with writing handedness: r = 0.68, P < 10 -10 ; with all others: r ≥ 0.93, P < 10 - 10 ).

To assess the link between general and task-specific handedness, the number of individuals reporting a left hand preference for a given number of specific tasks was computed for both general right-and left-handedness (Table 3). Independence between general and specific hand preference was significantly rejected (Fisher exact test on a contingency table, P < 10 -10 ). Only 49 individuals (or 10.4%) declared a left-handed preference for all the specific tasks and general left-handedness.

However, when writing handedness was removed, this number rose to 82 (or 17.4%). Overall, 32 individuals (6.8%) declared a hand preference for at least one specific task (writing excluded) that was different from their generalized-declared handedness. The figure dropped to 13 individuals (2.8%) when this discrepancy occurred for at least two specific tasks, and it dropped to 7 individuals (1.5%) for at least three specific tasks. Only 2 individuals (0.4%) declared an equal number of right and left preferences across the specific tasks: one declared general right-handedness and the other declared general left-handedness. If a (arbitrary) criterion of concordant laterality for at least seven of the specific tasks is used to assign handedness, then generalized-declared handedness is consistent with assigned handedness for 98.5% (or 463/470) of the cases, corresponding to 99.5% (370/372) right-handers and 94.9% (93/98) left-handers.

H and performance

Relative hand grip (RHG) was computed for 469 individuals. RHG was not influenced by age (P = 0.59) or whether individuals started using their preferred hand (P = 0.17). Sex, generalized-declared handedness and the interaction between the two had a significant effect (P = 0.0023, 3.9x10 -7 and 0.00078, respectively). For both sexes, individuals who declared a right-hand preference had higher hand-grip strength for the right hand (Figure 1). Individuals who declared a left-hand preference had higher hand-grip strength for the left hand, although this was significant only for males (Figure 1).

Relative hand skill (RHS) was computed for 457 individuals. RHS was not influenced by age (P = 0.15), sex (P = 0.68), or by the interaction between generalized-declared handedness and sex (P = 0.26). The starting hand had an effect for right handers (RHS was lower when individuals started the peg-moving test using their non-preferred hand, P = 1.8x10 -5 ) but not for left-handers (P = 0.69). The participants were significantly (P = 1.9x10 -11 ) faster on the peg-moving task with their preferred hand than with their non-preferred hand (Figure 2). Predicting generalized handedness from specific tasks Each of the 10 specific hand-preference variables was evaluated for its ability to predict declared-generalized handedness above chance level (Table 4). Each of the variables was able to predict at least 97.8% of generalized-declared handedness. The only exception was writing handedness, which predicted only 90.1% of the cases. Taken simultaneously, these 10 specific handedness variables significantly (P < 10 -10 ) predicted the general handedness above chance level.

Distinguishing tasks requiring either a power grip or a precision grip did not significantly improve prediction accuracy. The same procedure was applied for the two measures of relative hand performance (hand grip and hand skill). Neither was able to predict handedness above chance level (Table 4). Taken simultaneously, the 2 performance variables predicted generalized-declared handedness significantly above chance level, although 13.9% individuals were incorrectly assigned. When all the handedness variables (the 10 specific handedness variables, hand grip and hand skill) were considered simultaneously, 99.1% of the individuals were correctly assigned. There were 4 individuals incorrectly assigned (or 0.9%).

Discussion

Handedness is usually viewed from three different aspects: (a) the relative preference for one hand in the execution of various unimanual tasks, (b) the greater skilfulness of one hand in the performance of these tasks, or (c) the greater strength of one hand (Annett, 1970;[START_REF] Chau | Comparison between estimates of hand volume and hand strengths with sex and age with and without anthropometric data in healthy working people[END_REF][START_REF] Peters | Description and validation of a flexible and broadly usable handedness questionnaire[END_REF]. These aspects are not exclusive, as higher skilfulness or higher strength explain relative preference, and vice-versa. In the present sample, declared-generalized handedness was overall consistent with task-declared handedness across 10 specific tasks for each individual, and with a measure of strength and a measure of skilfulness, suggesting that general handedness seems to be a valid concept in this population.

When a participant declared their general handedness, right or left, this meant that most daily lateralized tasks were performed with the declared hand. The 10 tasks used were all familiar to the population sampled. Most of them are farmers and use a knife, machete, saw, and hammer frequently; many of the women on Flores are weavers and are familiar with sewing and the use of scissors. Writing is common because education until elementary school is compulsory. In a traditional society based on agriculture, heavy daily tool use is common for both sexes. In addition, as the market economy is limited on Flores, many items such as fishing boats, fences, beams, floorboards, handles, and others are still self-made. During the interviews in the villages, we came across several individuals using a tool (machete, axe, saw, needle, knife, spoon, etc.) while working, cooking or playing. Even though a precise quantification remains to be done, hand specialization is probably an adaptation for this intense and daily tool use, generating a general manual handedness.

Additionally, some tasks are probably functionally redundant: it seems logical that if one hand is specialized for cutting, the same hand will also be specialized for sawing. This is because some features, such as muscle strength and mass, developed for a particular specialization could also be mobilized for other similar tasks [START_REF] Gritsenko | Biomechanical constraints underlying motor primitives derived from the musculoskeletal anatomy of the human arm[END_REF]. This process may explain why the frequent performance of several different unimanual tasks generates a general hand specialization.

Handedness for the ten tasks was measured using self-reporting, rather than observing hand-use. Observation of unsolicited hand usage is not frequently reported, and generally corresponds to analysis of ethnographic video footages, providing a low sample size (G/wi, Hadza, Himba and Yonamamö, Table 1). Observation of solicited behaviours is also reported (Jimi valley and Eipo, Table 1), although an ecological validation is required, particularly when the solicited behaviour introduces social interferences, as it is often the case in traditional settings. In industrialized countries, questionnaire and performance-based measures of preference on adults are correlated (e.g. agreement of 98% for throwing, [START_REF] Raczkowski | Reliability and validity of some handedness questionnaire items[END_REF] and test-retest questionnaires on e.g. throwing and hammering handedness have produced 100% concordant responses [START_REF] Coren | The validity and reliability of self-report items for the measurement of lateral preference[END_REF]. Here, whenever the validity of self-reporting was evaluated by the observation of unsolicited lateralized tasks, observed handedness was 100% consistent.

Similarly, declared-generalized handedness was fully concordant with observed handedness in Bobodioulasso area, Burkina Faso [START_REF] Faurie | Variation in the frequency of left-handedness in traditional societies[END_REF].

Apparently, one's own handedness is confidently known, suggesting that biases are minimal for handedness information collected through self-declarations.

Hand-grip strength is known to decrease with age and to be higher in men than in women (Innes, 1999). Interestingly, relative hand grip strength is independent of age and is thus a useful comparative measure of handedness. On Flores, the right-handed participants of both sexes had higher hand-grip strength for the right hand (RHG >1, Figure 1). This result seems robust, as it has been reported for other Asian populations (e.g. Singapore: [START_REF] Incel | Normative data on hand grip strength in a Greek adult population[END_REF] and western countries (e.g. Germany, Greece, Switzerland: [START_REF] Günther | Grip strength in healthy caucasian adults: reference values[END_REF]Mitsionis, Pakos, Stafilas, Paschos, Papakostas, & Beris, 2009;[START_REF] Werle | Age-and genderspecific normative data of grip and pinch strength in a healthy adult Swiss population[END_REF]. The converse was true for the lefthanders, who displayed a higher hand-grip strength for the left hand (RHG <1, Figure 1) for both sexes, although the effect for females was smaller. Hand skill, as measured by a peg-moving task, is known to be influenced by age and sex [START_REF] Gilbert | Adult norms for a commercially available Nine Hole Peg Test for finger dexterity[END_REF]Mathiowetz, Kashman, Volland, Weber, & Dowe, 1985). Here, however, relative hand skill was independent of age and sex and is thus a useful comparative measure of hand skill. When the participants used their preferred hand, they were faster than when they used their non-preferred hand (RHS < 1 for right-handers, and RHS > 1 for left-handers, Figure 2).

The twelve measures of handedness (10 tasks, RHG, and RHS) were overall consistent with generalized-declared handedness (Table 4), suggesting that ambidexterity is reduced in this population. True ambidexterity (being able to use both hands with equal ease for a specific unimanual task) is uncommon, particularly when the task is specialized. For example, only one ambidextrous pitcher (or hand-switcher) able to perform at a championship level has ever been recorded during 110 years of history of baseball, despite such strategy to have a higher payoff than either only right or left pitchers [START_REF] Goldstein | Evolutionary" stable strategy of handedness in major league baseball[END_REF]. Similarly, only 1.5% ambidextrous writers have been recorded from a sample of 1,355 individuals from New Zealand [START_REF] Connolly | The measurement of handedness: A cross-cultural comparison of samples from England and Papua New Guinea[END_REF]. In this sample from Flores and Adonara, true ambidexterity was also uncommon: for any given task, its frequency was lower than 0.9%. This low frequency of ambidexterity is consistent with hand specialization in a context of frequent tool usage in order to increase precision and efficiency. Precision is essential when potentially dangerous tools are used, such as a knife, machete, hammer, or saw, in order to reduce self-injury and bodily harm. Ambidexterity across tasks, when an individual uses one hand for a task and the other hand for another task, is more common (referred to as ambilaterality). When only two tasks are considered (writing and throwing), 5.3% of men are mixed-handed according to a large sample (N > 300,000) of American men aged 20-50 years old [START_REF] Gilbert | Adult norms for a commercially available Nine Hole Peg Test for finger dexterity[END_REF]. When more tasks are considered, as in the classical Edinburgh Inventory (10 tasks) and its variants [START_REF] Dellatolas | On the use (and misuse?) of the Edinburgh Handedness Inventory[END_REF], this proportion is approximately 30-50%, depending on the criteria used to define mixed-handedness (e.g., [START_REF] Oldfield | The assessment and analysis of handedness: The Edinburgh Inventory[END_REF][START_REF] Dellatolas | On the use (and misuse?) of the Edinburgh Handedness Inventory[END_REF]Millencovic & Dragovic, 2012).

The frequency of ambilaterality in this sample from Flores and Adonara is less than 1%, corresponding to 4 individuals. This percentage cannot be considered a population estimate, as some left-handers were non-randomly sampled in order to increase the frequency of left-handedness for comparison purposes. Thus, considering that ambilateral people are probably declaring a left preference more frequently than a right one, this percentage is therefore a maximum value for a population estimate. No special characteristics seem to be associated with the four individuals who did not have a clear general lateralization across tasks: all were farmers (except one whose occupation was not recorded), they represented both sexes (three males and one female), they were between 33 and 52 years old, and they lived in different villages.

The results of this study indicate that for Indonesian men and women from Flores and Adonara, right-and left-handedness are meaningful categories. Thus, in these traditional populations, generalized-declared handedness seems to be a valid and sufficient source of information to identify handedness category as it was ascertained by handedness for various specific tasks and relative hand performance and skill.

Table 1. Handedness studies from traditional populations. The year when the data was recorded (Year), the sample size (N), whether or not manual specialization and a sex effect could be studied, and an estimated reliability are shown. The total number of moves of a trial is thus 5x3. A second trial is done with the other hand, and this process is repeated three times.

  RHG and RHS were negatively correlated (Pearson's correlation = -0.32, t = -7.2, df = 451, P = 2.1x10 -12 ), thus low values of RHS (skilled right handers) are associated with high values of RHG (strengthful right handers).

Figure 1 .

 1 Figure 1. Fitted relative difference in hand-grip strength according to sex and declared general handedness. Error bars are plus/minus one standard deviation.

Figure 2 .

 2 Figure 2.Fitted relative difference in hand skill according to sex and declared general handedness. Error bars are plus/minus one standard deviation.

Figure S1 .

 S1 Figure S1. Starting position of the peg-moving task. A board of and English version of the peg solitaire game is used, with two sets of three pegs with different colours. Tweezers (depicted) are used to move the pegs. A first move (arrow 1) is to jump a brown peg orthogonally over an adjacent red peg into a hole two positions away. The other arrows depict the four other moves of one row.

Figure 1 Figure 2 Figure S1

 12S1 Figure 1

Table 2 .

 2 Number of individuals reporting hand preference for general handedness and for ten specific tasks.

				Possibility to study :
				Manual	Sex
	Population Year	N	specialization	effect Reliability Reference
	Inuit	1892-1971 211	No a	Yes	Yes e	Faurie et al. 2005
	Eipo	1974-1980 1,295	No b	No c	Yes e	Faurie et al. 2005
	G/wi	1976	41	No a	No d	Yes e	Marchant et al. 1995
	Yanamomö 1989	31	No a	No d	Yes e	Marchant et al. 1995
	Himba	1990	37	No a	No d	Yes e	Marchant et al. 1995
	Jimi Valley 1990	185	Yes	Yes	? f,g	Connolly & Bishop, 1992
	Ntumu	1998	246	No b	Yes	Yes h	Carrière & Raymond, 2000
	Dioula	2001	346	No b	Yes	Yes h	Faurie et al. 2005
	Baka	2002	403	No b	Yes	Yes h	Faurie et al. 2005
	Kreyol	2003	333	No b	Yes	Yes h	Faurie & Raymond, 2005
	Hadza	2005-2009 42	No a	No d	Yes e	Cavanagh et al. 2016
	Eipo	2010	621	No a	Yes c	? f	Schaafsma et al. 2012
	Flores	2015-2016 480	Yes	Yes	Yes h	This study
	a. Individual data for more than one task were not recorded or reported. b. Only one task was recorded. c.
	Only one sex studied. d. Sample size too low. e. Individual laterality recorded from photos or movies
	made for another purpose. f. Solicited behaviour with audience. g. Some tasks culturally meaningless. h.
	Interviews partially cross-checked with spontaneous performance.

Table 4 .

 4 Accuracy of prediction of generalized-declared handedness for each individual handedness variable and for different groupings. CI refers to confidence interval. P-values refer to a two-sided exact binomial test of departure from random assignment (baseline of 80.3%). Bold characters indicate significant (P < 0.05/12 = 0.0042) values, taking into account multiple testing.

	480
	Handedness variables	Prediction
		accuracy(%)	95 % CI	P-value
	Power grip tasks:
	Throwing	98.4	96.8 -99.4	< 10 -10
	Racquet holding	98.7	97.1 -99.5	< 10 -10
	Knife/machete	98.7	97.1 -99.5	< 10 -10
	Hammer	98.7	97.1 -99.5	< 10 -10
	Saw	99.3	98.1 -99.9	< 10 -10
	All	99.3	98.1 -99.9	< 10 -10
	Precision grip tasks:
	Marble play	98.7	97.1 -99.5	< 10 -10
	Spoon	98.0	96.2 -99.1	< 10 -10
	Sewing	98.8	97.4 -99.6	< 10 -10
	Writing	90.1	. 87.0 -92.8	9.4 10 -10
	Scissors	97.8	95.9 -98.9	< 10 -10
	All	99.1	97.7 -99.7	< 10 -10
	All ten tasks	99.1	97.7 -99.8	< 10 -10
	Performance:
	Hand grip	82.1	78.2 -85.5	0.14
	Hand skill	83.0	79.2 -86.4	0.05
	All	86.1	82.6 -89.2	1.9 10 -4
	All variables:	99.1	97.7 -99.7	< 10 -10
		23

Acknowledgements

We are very grateful to Valérie Durand for bibliographic help and to the Program Magister Menuju Doktor untuk Sarjana Unggul (PMDSU) 2015 for providing funding to BS. This is contribution ISEM 2017-XXX of the Institute of Evolutionary Science of Montpellier.

References Annett, M. 1970. A classification of hand preference by association analysis. British Journal of Psychology, 61, 303-321. doi:10.1111Psychology, 61, 303-321. doi:10. /j.2044Psychology, 61, 303-321. doi:10. -8295.1970.tb01248.x .tb01248.x