Orientador: Carlos Alberto Carrasco Altemani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T09:22:29Z (GMT). No. of bitstreams: 1 Alves_ThiagoAntonini_D.pdf: 12931422 bytes, checksum: b3858d05581229381f7d14684d29e979 (MD5) Previous issue date: 2010 / Resumo: A transferência de calor conjugada por convecção forçada e condução de três aquecedores 2D montados rentes ou protuberantes na placa inferior (substrato) de um canal de placas paralelas foi investigada numericamente em regime permanente. Uma taxa uniforme de geração de calor foi assumida em cada aquecedor e seu resfriamento ocorreu por meio de um escoamento forçado de ar com propriedades constantes em regime laminar. Na entrada do canal, os perfis de velocidade e de temperatura do escoamento eram uniformes. Este problema está relacionado ao resfriamento de componentes eletrônicos montados numa placa de circuito impresso. Para um substrato adiabático, o resfriamento dos aquecedores ocorre apenas por convecção forçada. Para um substrato condutivo, dois mecanismos para a transferência de calor dos aquecedores para o escoamento fluido foram considerados. Um, por convecção forçada, diretamente das superfícies dos aquecedores em contato com o escoamento e outro, por condução através das interfaces substrato-aquecedor. As equações de conservação foram resolvidas dentro de um domínio único, que englobou as regiões sólidas e de fluido, através de um procedimento acoplado. Nesta Tese foi proposto um descritor invariante do processo conjugado de transferência de calor por convecção forçada e condução, por meio de coeficientes de influência conjugados g+, agrupados numa matriz quadrada G+. Com este descritor, a temperatura de cada aquecedor foi determinada a partir de taxas arbitrárias de geração de calor nos aquecedores. Os resultados foram obtidos para números de Reynolds na faixa de 600 a 1900, correspondendo a velocidades médias de entrada do ar no canal na faixa de 0,5 m/s a 1,5 m/s. Os efeitos da razão entre a condutividade térmica do substrato e a do ar foram estudados na faixa de 0 (substrato adiabático) a 80, uma faixa típica de materiais de circuito impresso. A altura dos aquecedores variou entre 0 (aquecedores rentes) e 35% em relação à altura do canal, sendo que em todos os casos o aquecedor possuía uma condutividade térmica 500 vezes maior do que a do ar. / Abstract: The conjugate heat transfer by forced convection and conduction from three 2D heaters either flush mounted or protruding from the lower plate (substrate) of a parallel plates channel was investigated numerically under steady state conditions. A uniform heat generation rate was assumed in each heater and the cooling was performed by means of a forced air flow with constant properties in the laminar regime. At the channel entrance the flow velocity and temperature profiles were assumed uniform. This problem is related to the cooling of electronic components mounted on a circuit board. For an adiabatic substrate, the heaters are cooled only by forced convection. For a conductive substrate, two mechanisms were considered for the heat transfer from the heaters to the fluid flow. One, by forced convection, directly from the heaters surfaces in contact with the flow, and the other, by conduction through the heaters-substrate interfaces. The conservation equations were solved through a coupled procedure within a single calculation domain comprising the solid and fluid regions. In this Thesis an invariant descriptor of the conjugate forced convection and conduction heat transfer was proposed by means of conjugate influence coefficients g+ which were grouped in a square matrix G+. With this descriptor, the temperature of each heater was obtained from an arbitrary distribution of the heat generation rate in the heaters. The results were obtained for Reynolds numbers Re in the range from 600 to 1900, corresponding to average air velocities in the channel entrance from 0.5 m/s to 1.5 m/s. The ratio of the substrate plate thermal conductivity relative to that of the air was considered in the range from 0 (adiabatic substrate) to 80, typical of printed circuit boards. The heaters' height in the channel ranged from 0 (flush mounted) to 35 % of the channel height, while their thermal conductivity was always assumed equal to 500 that of the air. / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica

Orientador: Carlos Alberto C. Altemani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-22T23:26:55Z (GMT). No. of bitstreams: 1 Martins_EduardoBalster_D.pdf: 10914423 bytes, checksum: ecaf97a75c72546a03b89a1659ad36c3 (MD5) Previous issue date: 1997 / Resumo: Uma investigação do resfriamento conjugado de placas aquecidas suspensas numa cavidade preenchida com ar foi realizada. Duas configurações da cavidade em estudo foram consideradas. Numa delas havia uma única placa, suspensa verticalmente, em posição central, no interior da cavidade. Na outra configuração havia duas placas idênticas suspensas em posições simétricas com relação ao plano médio vertical da cavidade. As paredes laterais e inferior da cavidade eram de material isolante. A parede superior era uma placa isotérmica de material condutor. Um aparato experimental foi construído e a condutância térmica global entre cada placa e o ar ambiente fora da cavidade foi obtida sob condições de regime permanente. O número de Rayleigh da cavidade encontrava-se dentro da faixa de regime laminar para todos os ensaios realizados. Os resultados experimentais foram comparados com os resultados de simulações bidimensionais. Os mecanismos conjugados de condução, convecção e radiação térmica foram incluídos no modelo de análise térmica da cavidade. A solução das equações de conservação foram obtidas numericamente por meio de uma combinação de um método de volumes finitos com o método das radiosidades. Os efeitos de sombreamento provocados pela presença das placas no interior da cavidade foram levados em consideração. Das simulações realizadas foram obtidas as condutâncias térmicas globais para as placas, as frações de contribuição de cada modo de transferência de calor no resfriamento de cada placa e da cavidade e as temperaturas no interior da cavidade / Abstract: An investigation of the conjugate heat transfer tTomheated plates suspended in an air filled enclosure was performed. Two distinct configurations for the enclosure were considered. In the first, there was only one heated plate inside the enclosure, suspended in the central position. In the other configuration, there were two heated plates suspended inside the enclosure. They were symmetrically located with respect to the enclosure's vertical midplane. The side and the bottom walls of the enclosure were insulated, but the top wall was a conductive isothennal plate. An experimental apparatus was built and the global therrnal conductance of the heated plates to the ambient air outside the enclosure was obtained under steady state conditions. The Rayleigh number inside the enclosure was within the larninar range. The experimental results were compared with those of a two-dimensional simulation. The conjugate mechanisms of conduction, convection and therrnal radiation were included in the model for the thennal analysis of the enclosure. The solution of the conservation equations was obtained numerically via a combination of the finite volumes and the radiosities methods. The blockage effect of the heated plate to thermal radiation inside the enclosure was taken into account. From this simulation, the global thermal conductance of the heated plate, the distribution of the heat transfer among the three mechanisms, as well as values of the temperature inside the enclosure were obtained. / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica

Medidas de tempo de vôo, em cinco diferentes temperaturas, foram realizadas em enxofre ortorrômbico para vários campos elétricos, tanto positivos como negativos. O trânsito dos portadores negativos foi mais extensivamente analisado e para baixas intensidades de luz, isto é, o caso do sinal fraco, os seguintes fatos foram verificados; a) não foi detectada dependência da mobilidade com o campo elétrico; b) a razão da corrente no tempo t para a corrente inicial mostrou não ser uma função universal do tempo, (isto é, independente do campo aplicado). Transporte dispersivo, discernível através da dependência da mobilidade com o campo elétrico, foi detectado pelo fato a. Contudo, para o transporte não dispersivo nós devemos esperar que a corrente normalizada leve a uma função universal do tempo, somente dependente do tempo de captura e, eventualmente, do tempo de soltura dos portadores, contrário ao que foi encontrado em b. A parte principal desta tese foi dedicada a testar nossos resultados com modelos existentes e o efeito esperado da falha das suposições nos resultados. Nós fomos então levados a um novo modelo, o qual explicou razoavelmente os resultados; a luz joga portadores, não só no canal normal de condução, mas também em um nível extra, confinado à região superficial, caracterizado por uma mobilidade dependente da profundidade. Soluções numéricas foram obtidas para confirmar a validade das soluções analíticas aproximadas obtidas. Um modelo aproximado foi desenvolvido para explicar o efeito do campo elétrico na extração de portadores da zona iluminada / Time off light measurements, in five different temperatures, were carried out in orthorhombic sulphur for various electric fields, both positive and negative. The transit of negative carriers were more thoroughly analyzed and at low light intensities, that is, the small signal case, the following facts were well established; a) no electric field dependence of the mobility was detected, b) the ratio of the current at a time t to the initial current was found not to be a universal function of the time (that is, independent of the applied field). Dispersive transport, discernible through its field dependent electron mobility, is ruled out by a. However, for non dispersive transport, we should expect the normalized current to lead to a universal function of time, only dependent of the trapping and, eventually, de-trapping times of the carriers, contrary to what was found in b. The main part of this thesis was devoted to test our results with the existing models and the expected effect of the breakdown of the simplified assumptions on the results. We were thus lead to a new model, which reasonable explained the results: light put carriers, not only in the normal conduction channel, but also in an extra level, confined to the surface region, characterized by a depth dependent mobility. Computer solution were carried out to confirm the validity of approximate analytic solutions thus obtained. An approximate model was also developed to explain the effect of the electronic field on the extraction of carriers from the illuminated zone

O desenvolvimento de um método eficiente de avaliação prognóstica precoce seria de grande utilidade na seleção de lactentes com plexopatia braquial obstétrica para cirurgias de reconstrução do plexo braquial. Realizamos estudos de condução motora em 54 pacientes entre 10 e 60 dias de vida. Foram comparadas lado a lado as amplitudes dos potenciais de ação musculares compostos dos nervos axilar (músculo deltóde), musculocutâneo (músculo bíceps), radial proximal (músculo tríceps), radial distal (músculo extensor comum dos dedos), mediano (eminência tenar) e ulnar (eminência hipotenar). A relação entre a amplitude do potencial motor do lado lesado sobre o lado são foi chamada de Índice de Viabilidade Axonial (IVA), sendo este calculado tanto a partir da amplitude negativa como da amplitude pico-a-pico. Os pacientes foram seguidos clinicamente e classificados em três grupos: Grupo A, com recuperação total até os seis meses de vida; Grupo B, recuperação satisfatória até os doze meses de vida, e Grupo C, recuperação insatisfatória até os doze meses de vida. Analisamos a curva ROC (Receive Operator Characteristic Curve) de cada IVA para definir o melhor ponto de corte para detecção dos pacientes do Grupo C (mau prognóstico). Para o nervo axilar, o ponto de corte ideal foi IVA menor que 10%, com sensibilidade de 88,2% e especificidade de 89,2% ou 91,9%. Para o nervo musculocutâneo, o ponto de corte foi a ausência de potencial de ação motor, com sensibilidade de 88,2% e especificidade de 73,0%. Para o nervo radial proximal, o ponto de corte foi IVA menor que 20%, com sensibilidade de 82,4% ou 94,1% e especificidade de 97,3% ou 100%. Para o nervo radial distal, o ponto de corte foi IVA menor que 50%, com sensibilidade de 76,5% ou 82,4% e especificidade de 97,3%. Para o nervo ulnar, o ponto de corte foi IVA menor que 50%, com sensibilidade de 58,8% e especificidade de 97,3% ou 100%. O IVA do nervo mediano teve um desempenho ruim e seu uso não pode ser recomendado. Os IVAs dos nervos radial proximal, radial distal e ulnar apresentaram maior especificidade do que o critério clínico mais utilizado para a avaliação prognóstica, ou seja, ausência de função bicipital aos três meses de vida. A sensibilidade dos IVAs dos nervos axilar, musculocutâneo, radial proximal e radial distal foram equivalentes à do critério clínico. A utilização do estudo de condução motora entre 10 e 60 dias de vida forneceu uma avaliação prognóstica mais precoce e mais específica do que o critério clínico, podendo ser utilizada para indicação cirúrgica destes pacientes. / Early prognostic assessment of obstetric brachial plexopathies would be a major step for rational selection of infants for brachial plexus surgery. We performed nerve conduction studies in 54 patients from 10 to 60 days of life. We compared sideto-side the compound muscle action potentials amplitudes from the axillary (deltoid muscle), musculocutaneous (biceps), proximal radial (triceps), distal radial (extensor digitorum communis), median (thenar eminence) and ulnar nerves (hypothenar eminence). The ratio between the amplitude of the affected limb and that of the healthy side was called Viability Axonal Index (VAI), which was calculated using both the negative and the peak-to-peak amplitudes. The patients were followed-up and classified in three groups: Group A, with full recovery at six months of age; Group B, with satisfactory recovery at twelve months of age, and Group C, with poor recovery at twelve months of age. We analyzed the ROC (Receive Operator Characteristic) curve of each VAI to define the best cut-off point for detection of Group C patients (bad prognosis). The best cut-off point for the axillary nerve was a VAI of less than 10%, whith sensibility of 88.2% and specificity of 89.2% or 91.9%. For the musculocutaneous nerve, the cut-off point was an absent motor action potential, with sensibility of 88.2% and specificity of 73.0%. For the proximal radial nerve, the cut-off point was a VAI of less than 20%, with sensibility of 82.4% or 94.1% and specificity of 97.3% or 100%. For the distal radial nerve, the cut-off point was a VAI of less than 50%, with sensibility of 76.5% or 82.4% and specificity of 97.3%. For the ulnar nerve, the cut-off point was a VAI of less than 50%, which sensibility of 58.8% and specificity of 97.3% or 100%. The VAI from the median nerve had a poor performance and its use could not be recommended. The VAIs from proximal radial, distal radial and ulnar nerves had better specificities compared to the most used clinical criterion: absence of biceps function at three months of age. The VAIs sensitivities from axillary, musculocutaneous, proximal radial and distal radial nerves were equivalent to the clinical criterion. The use of motor conduction studies between 10 and 60 days of age yielded an earlier and more specific prognostic estimation than the clinical criterion, and could be used for indication of surgery in these patients.

Orientador: Juliana Trindade Clemente Napimoga / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-24T14:35:21Z (GMT). No. of bitstreams: 1 Freitas_FabianaFurtado_M.pdf: 645432 bytes, checksum: e82ee77ed413f662feeacfa6a76c4c23 (MD5) Previous issue date: 2014 / Resumo: O diabetes induz resposta inflamatória acentuada resultando em maior movimentação dental por dispositivos ortodônticos. Sendo assim, este estudo teve como objetivo avaliar se o aumento da resposta inflamatória, decorrente do tracionamento dental por um dispositivo ortodôntico, induzido pelo diabetes altera a excitabilidade neuronal no gânglio trigeminal. Para este estudo foram utilizados ratos Wistar (±150 g, n= 4-6/grupo) tratados com injeção intraperitoneal de tampão citrato (veículo; Normoglicêmicos ¿ NG), estreptozotocina 75 mg/kg (Diabético ¿ DG), ou estreptozotocina 75 mg/kg + injeção subcutânea de insulina (Diabético tratado com insulina ¿ IG). Vinte e oito dias após o tratamento foi instalado um dispositivo ortodôntico e a movimentação dentária foi avaliada nos dias 0, 1, 3, 6 ou 12. Após o tempo correspondente, os animais foram anestesiados e a maxila, gânglio trigeminal e tecido gengival removidos e submetidos à análise para quantificação da movimentação dentária e análise bioquímica (ELISA) para avaliação da liberação de glutamato, Fator de Necrose Tumoral-alfa (TNF-?), Interleucina 1-beta (IL-1?), Substância P (SP) e Peptídeo Relacionado ao Gene da Calcitonina (CGRP). Os resultados demonstraram que o diabetes aumentou significativamente o movimento dental induzido pelo tracionamento ortodôntico nos dias 1, 3 e 6 quando comparado aos animais NG e IG (p<0.05: Two-way ANOVA, Teste de Bonferroni). Corroborando com esses resultados, os animais DG demonstraram maior liberação de TNF-? e IL-1? no tecido gengival em relação aos animais NG e IG (p<0.05). No entanto, apesar do acentuado processo inflamatório nos animais DG, a liberação de glutamato (gânglio trigeminal), SP e CGRP (tecido gengival) foi significativamente reduzida (p<0.05). Os resultados sugerem que a ativação neuronal no gânglio trigeminal é reduzida no diabetes / Abstract: Diabetes is known to result in a greater inflammatory response that in turn accentuated orthodontic tooth movement. Thus, this study aimed to evaluate if the higher inflammatory response induced by the orthodontic tooth movement in diabetic animals changes the neuronal excitability in the trigeminal ganglia. For that, Wistar rats (± 150 g, n=4-6/group) were treated with an intraperitoneal injection of citrate buffer (vehicle; Normoglycemic ¿ NG), streptozotocin 75 mg/kg (Diabetic ¿ DG) or streptozotocin 75 mg/kg + subcutaneous injection of insulin (Diabetic treated with insulin ¿ IG). Twenty-eight days after the treatment, an orthodontic appliance was placed and the tooth movement was evaluated at days 0, 1, 3, 6 and 12. After the corresponding time, the animals were terminally anesthetized and their maxillae, trigeminal ganglia and gingival tissue were removed and submitted to analyze the amount of tooth movement and biochemical analysis (ELISA) to measure the release of glutamate, Tumor Necrose Factor-alpha (TNF-?), Interleukin 1-beta (IL-1?), Substance P (SP) and Calcitonin Gene-Related Peptide (CGRP). The results demonstrated that diabetes accentuated orthodontic tooth movement at days 1, 3 and 6 when compared with NG and IG (p<0.05: Two-way ANOVA, Bonferroni¿s test). Corroborating these results, DG rats demonstrated higher release of TNF-? and IL-1? than that observed for the NG and IG rats (p<0.05). Although the greater inflammatory response induced in DG rats, the release of glutamate, SP and CGRP were significantly reduced (p<0.05). The results suggest that neuronal activation in trigeminal ganglia is reduced in diabetes / Mestrado / Odontopediatria / Mestra em Odontologia

Orientador: Carlos Alberto Carrasco Altemani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-24T04:10:43Z (GMT). No. of bitstreams: 1 MarchiNeto_Ismael_D.pdf: 4845997 bytes, checksum: b5f466a0bc722eba5f754b6c4ef08357 (MD5) Previous issue date: 2014 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital. / Abstract: The abstract is available with the full electronic document. / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica

Evaporated thin film sandwich structures of Au-SiOX-Au have been studied. These normally show electroforming effects and subsequently electron emission, electroluminescence, negative resistance and thermal-voltage memory effects. Previous work in the field is critically reviewed. It was shown that the time dependence of the device current and emission current can be explained by making certain modifications to the filamentary conduction theory of Dearnaley. Detailed direct current-voltage measurements have revealed the existence of two different types of breakdown behaviour. At voltages less than 20 V single-hole breakdowns were observed, while in the voltage range 20-30 V large scale irreversible breakdown behaviour took place. The dependence of the voltage at which this occurs (Vß) on insulator thickness and temperature, together with measurements of the device temperature at breakdown and visual evidence of damage after breakdown, has led to the conclusion that this type of breakdown is a thermal effect. Such measurements also pointed to the existence of a high field region within the insulator, and potential distribution measurements confirmed this hypothesis. The high field region was also in evidence at low temperatures where the device current (Ic) showed a log Ic α Vb1/2 dependence on applied voltage (Vb). Measurements of electron attenuation lengths in SiOx gave values of 400-1000 Å irrespective of temperature. The temperature independence was consistent with the emitted electron energy distributions at 77 and 300 K. It was shown that electrons underwent Bragg diffraction through the top Au electrode. The angular distribution of emitted electrons became more isotropic with increasing voltage. Measurements on other systems showed that Al-SiOx/B2O3-Al devices could withstand very high voltages and give improved emission efficiency, while Au-CaBr2-Au and Au-Si3N4-Au devices showed very high initial currents and current-voltage characteristics which were irreversible.

En mécanique des matériaux et des structures, l’interface entre deux composants matériels ou deux éléments structuraux est traditionnellement et le plus souvent supposé parfaite. Au sens mécanique, une interface parfaite est une surface à travers laquelle le vecteur de déplacement et le vecteur de contrainte sont tous les deux continus. L’hypothèse des interfaces parfaites est inappropriée dans de nombreuses situations en mécanique. En effet, l’interface entre deux corps ou deux parties d’un corps est un endroit propice aux réactions physico-chimiques complexes et favorable à l’endommagement mécanique. L’intérêt pour les interfaces imparfaites devient depuis quelques années grandissant avec le développement des matériaux et structures nanométriques dans lesquels les interfaces et surfaces jouent un rôle prépondérant. A partir de la configuration de base où une interphase de faible épaisseur sépare deux phases, ce travail établit trois modèles d’interface imparfaite généraux qui permettent de remplacer l’interphase par une interface imparfaite dans les cas de la conduction thermique, de l’élasticité linéaire et de la piézoélectricité sans perturber les champs en questions à une erreur fixée près. La dérivation de ces modèles est basée sur le développement de Taylor et sur une approche originale de géométrie différentielle indépendante de tout système de coordonnées. Les trois modèles généraux permettent non seulement de mieux appréhender certains modèles phénoménologiques d’interface imparfaite mais aussi de décrire les effets d’interface que les modèles existants ne sont pas en mesure de prendre en compte. Les modèles d’interface imparfaite établis sont appliqués dans la détermination des propriétés effectives thermiques, élastiques et piézoélectriques d’un matériau composite constitué d’une matrice renforcée par des particules ou fibres enrobées d’une interphase. La méthode utilisée pour rendre compte des effets des interfaces imparfaites sur les propriétés effectives repose sur une condition d’équivalence énergétique qui ramène un matériau hétérogène avec interfaces imparfaites à un matériau hétérogène avec interfaces parfaites / In mechanics of materials and structures, the interface between two material components or two structural elements is traditionally and the most often assumed to be perfect. In mechanics, a perfect interface is a surface through which the displacement and stress vectors are continuous. The assumption of the perfect interfaces is inappropriate in many situations in mechanics. Indeed, the interface between two bodies or two parts of a body is a place propitious to complex physicochemical reactions and vulnerable to mechanical damage. The interest in imperfect interfaces has become for a few years growing with the development of nanometric materials and structures in which the interfaces and surfaces play a preponderant role. Starting from the basic configuration where an interphase of thin thickness separates two phases, this work establishes three general models of imperfect interface which make it possible to replace the interphase by an imperfect interface in the cases of thermal conduction, linear elasticity and piezoelectricity without disturbing the fields in questions to within a fixed error. The derivation of these models is based on the development of Taylor and an original coordinate-free approach of differential geometry. The three general models make it possible not only to get a better understanding of certain phenomenological models of imperfect interface but also to describe the effects of interface which the existing models are not able to take into account. The established models of imperfect interface are applied to determining the thermal, elastic and piezoelectric effective properties of composite materials consisting of a matrix reinforced by particles or fibers coated with an interphase. The method used to account for the effects of imperfect interfaces on the effective properties rests on an energy equivalency which brings back a heterogeneous material with imperfect interfaces to a heterogeneous material with perfect interfaces

Neurography is the most objective and reliable measure of the peripheral nerve function, and it is used to diagnose both local and generalized neuropathies. Neurography can measure both motor and sensory nerve functions. The principle for sensory neurgraphy is to stimulate over the nerve and record proximal or distal from the stimulated electrode. At the Department of Clinical Neurophysiology, University Hospital Uppsala, a problem has been identified, in that young adult patients tend to show unexpected abnormal neurography values in relation to the expected, indicated by the reference limits, without clinical correlates. This concerns foremost the sensory amplitudes in median and ulnar nerves. The hypothesis is that the requirement of young adults’ amplitudes is too high. A reference material better including more subjects in this age group may solve the problem. Sensory nerve conduction studies were performed in 33 subjects, aged 15-30. The nerve functions were tested on median, ulnar and radial nerves. Surface electrodes were used for both recording and stimulation. The result shows that the presently used reference material for some nerves indeed has too high requirement for young adults. After increasing the reference material for younger age groups, the new reference limits has been changed and this should cause fewer false positive findings.

The purpose of this study was to investigate the difference in amplitude between M-response from m. Abductor pollicis brevis/m. Pronator quadratus and m. Abductor pollicis brevis/m. Abductor digiti minimi on patients with carpal tunnel syndrome, compared with control subjects. We wanted to see if m. Pronator quadratus is a better alternative than m. Abductor digiti minimi as comparison with m. Abductor pollicis brevis on patients with carpal tunnel syndrome. Nerve conduction studies were performed on 20 patients with carpal tunnel syndrome and on 31 healthy subjects. The test-retest result shows that this method was reproducible. The amplitude difference of m. Abductor pollicis brevis-m. Abductor digiti minimi, for the patients, was 1,5mV lower and the amplitude for m. Abductor pollicis brevis-m. Pronator quadratus was 2mV lower than for healthy subjects. Two of the patients were outside the 2SD for the m. Abductor pollicis brevis-m. Pronator quadratus difference but not on the m. Abductor pollicis brevis-m. Abductor digiti minimi. This may indicate that m. Pronator quadratus was better than m. Abductor digiti minimi in the comparison with the m. Abductor pollicis brevis amplitude.