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Made available in DSpace on 2022-05-01T13:41:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-01 Printed electronics is a reputable research area that aims at simple alternatives of manufacturing low-cost, eco-friendly, and biodegradable electronic devices. Among these devices, electrolyte-gated transistors (EGTs) stand out due to their simple manufacturing process and architecture. Here we report the study of printed EGTs with in-plane gate transistor (IPGT) architecture based on zinc oxide nanoparticles. The drain, source, and gate electrodes with two different W/L channel ratios were fabricated using a screen-printed carbon-based ink. We also produced a conventional top-gate transistor as a standard device, using the same structure of the IPGT described above with the addition of an indium tin oxide strip positioned over the electrolyte as the top-gate electrode. The IPGT with W/L = 5 presented a high mobility of 7.95 0.55 cm2 V-1 s-1, while the W/L = 2.5 device exhibited a mobility of 3.03 0.52 cm2 V-1 s-1. We found that the measured field-effect mobility of the device can be affected by the high contact resistance from the carbon electrodes. This effect could be observed when the device's geometric parameters were changed. Furthermore, we also found that the IPGT with W/L = 5 exhibited higher values for mobility and transconductance than the top-gate transistor, showing that the IPGTs architecture is a good approach for cheap and printed transistors with performance comparable to standard top-gate EGTs. School of Technology and Sciences Department of Physics S o Paulo State University - UNESP, SP Faculty of Science and Technology (FCT) CENIMAT/I3N Department of Materials Science Universidade NOVA de Lisboa CEMOP-UNINOVA School of Technology and Sciences Department of Physics S o Paulo State University - UNESP, SP

Made available in DSpace on 2022-04-29T08:33:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Theprinted electronics presents the outstanding proposal to produce low-cost, solution-processable, vacuum-free and flexible devices. In this context, many researchers have been made efforts to obtain printed memories that works with low voltage bias, high on/off ratio and storage stability. Here, we report a novel low-cost printed version of a memristor based on spray coated films of indigo and colloidal graphite. This memory showed high performance for printed memristors, being the most remarkable aspect of this device its high on/off ratio of 1.6 × 106 at -1.15 V, and 3.1 × 104 for voltages as low as +0.1 V. The pulse-test mode read at +0.1 V revealed very stable endurance characteristics even after 100 readings and retention time over 104 s, as desired by the printed electronics niches. The Physics Department Faculty of Science and Technology (FCT) São Paulo State University - UNESP, São Paulo The Physics Department Faculty of Science and Technology (FCT) São Paulo State University - UNESP, São Paulo FAPESP: 2019/03934-0 FAPESP: 2020/12282-4

Made available in DSpace on 2021-06-25T10:33:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Instituto Nacional de Ciência e Tecnologia em Eletrônica Orgânica Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The UV photocurrent response of thin films of wide bandgap semiconductors such as zinc oxide (ZnO) can be applied to a great number of electronic devices aiming applications in environmental sensing or UV-detection. Electronic devices like thin-film transistors or Schottky diodes commonly present multiple parameters of electrical characteristic, which can be beneficially exploited to provide more information than sensors based on purely resistive or capacitive response. We manufactured Schottky diodes using spray-coated ZnO and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) as an easy, simple and low-cost method for producing multiparametric UV-photodetectors. The diode parameters presented rectification ratios (RR) as high as 104 and ideality factors as low as 1.3, and their characteristic curves were analyzed by Cheung's method to determine the effect of UV irradiation on the ideality factor, series resistance and Schottky barrier height. The study of the photocurrent response from spray-coated ZnO films as a function of geometric parameters and UV intensity demonstrated a transition from bimolecular to monomolecular recombination process at higher irradiance values, as a result of the adsorption/desorption dynamics of molecular oxygen at the semiconductor/air interface. São Paulo State University – UNESP Faculty of Science and Technology (FCT) Physics Department São Paulo State University – UNESP Institute of Geosciences and Exact Sciences (IGCE) Physics Department São Paulo State University – UNESP Faculty of Science and Technology (FCT) Physics Department São Paulo State University – UNESP Institute of Geosciences and Exact Sciences (IGCE) Physics Department FAPESP: 2018/04169-3 FAPESP: 2019/01671-2 FAPESP: 2019/08019-9

Made available in DSpace on 2022-05-01T09:47:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Here we report the production and characterization of a low-cost supercapacitor with electrodes based on colloidal graphite. We characterized the as-prepared device in terms of cyclic voltammetry (CV), Galvanostatic charge/discharge (GCD), and impedance spectroscopy. The supercapacitor exhibited good electrochemical performance with a high capacitance of 22 F g-1for a discharge current of 2 mA. Long-term cyclability tests show that the device can keep about 85% of its capacitance after 500 cycles, even without encapsulation. We found power and energy densities of 110 W kg-1and 3 Wh kg-1, respectively. All the experimental results indicate that the colloidal graphite Aquadag® is a promising material for application in supercapacitors. Universidade Estadual Paulista (UNESP) Faculdade de Tecnologia e Ciências, SP Universidade Estadual Paulista (UNESP) Faculdade de Tecnologia e Ciências, SP

Made available in DSpace on 2019-10-06T17:13:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-07-30 Zinc acetate dihydrate solution was deposited onto glass and a thin layer of aluminum (10 nm), by spray pyrolysis at 450 °C, growing zinc oxide (ZnO) thin films. The ZnO formation occurs differently on aluminum due to the diffusion process forming AZO at the Al/ZnO interface. The films deposited onto the aluminum showed transmittance above 95%, associated with sheet resistance less than 40 Ω/sq. The high transmittance value with low sheet resistance is crucial for a good transparent electrode. Raman spectroscopy showed a higher degree of doping for films with thin layers of ZnO, and that the diffusion process is high at the Al/ZnO interface. The performance of the transparent electrode was evaluated through the characterization of the Schottky diode (Al:ZnO/ZnO/Au). The factor of ideality (n), resistance in series (Rs), and height of the barrier (ϕB) presented values of 3.79, 1022.6 Ω, and 0.97 eV, respectively. These results demonstrate the simple production of a transparent electrode by the in situ diffusion process using the spray pyrolysis technique. School of Technology and Applied Sciences São Paulo State University (UNESP) School of Technology and Applied Sciences São Paulo State University (UNESP)

Made available in DSpace on 2019-10-06T16:54:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Here we describe a screen-printed supercapacitor produced onto filter paper using poly (3, 4-ethylene dioxythiophene)-poly (styrene sulfonate) (PEDOT:PSS)/multiwall carbon nanotube (MWCNT) composite as active materials. We use a gel-like electrolyte based on poly (vinyl alcohol) and phosphoric acid (PVA/H3PO4), serving as both an ionic conductor and as an electrode separator. The electrodes are physically characterized through micro-Raman scattering analyses, sheet resistance measurements as a function of the printed number of layers and through scanning electron microscopy. The supercapacitor performance is investigated through impedance spectroscopy, equivalent circuit fitting, cyclic voltammetry (CV), long-term cycle stability and galvanostatic charge/discharge. The electrodes exhibit a low sheet resistance, reaching 17 Ω sq−1, being suitable for use as both electrode and the current collector. The supercapacitor shows good capability behavior over impedance spectroscopy and CV measurements, and 72% of capacitance retention after 1000 cycles. We find a maximum specific capacitance of 20,3 F g−1 for a charge/discharge current of 1 mA, and equivalent series resistance of 60 Ω leading to energy and power densities of 3,1 Wh kg−1 and 420 W kg−1, respectively. In conclusion, we describe here a flexible supercapacitor without metal collectors produced by a simple printing method. São Paulo State University (UNESP) School of Technology and Applied Sciences São Paulo State University (UNESP) School of Technology and Applied Sciences FAPESP: 2015/18091-8 FAPESP: 2018/02604-4

Made available in DSpace on 2018-12-11T17:35:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-04-01 The production of low cost sensors to monitor environment in some industrial sectors is a current need. In aviculture centers, for example, the concentration of ammonia gas is related to humidity, and it is necessary to control it to avoid contamination. With this need in mind, this paper presents the preparation and characterization of a low cost humidity sensor based on poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) and polyaniline fully printed onto paper by a commercial HP printer. Using electrochemical impedance spectroscopy, an equivalent circuit containing resistive and capacitive parameters was proposed. The resistive parameter R1 is related to values of ambient humidity. The R1 values showed a sensitive response of 200% when relative humidity changes 80%, taking 10 min to reach saturation point. Moreover, the device showed good stability when humidity remained constant. These results indicate that the proposed device is suitable for applying as a humidity sensor that costs less than 1 Euro cent. School of Technology and Sciences São Paulo State University (UNESP) School of Technology and Sciences São Paulo State University (UNESP)

Made available in DSpace on 2018-12-11T17:16:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-02-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The use of paper as a platform to manufacture organic electronic devices, electronic paper, has expanding potential for many applications because of several properties offered. In this work, we show a study of PEDOT:PSS printed by inkjet on bond paper, vegetal paper and sheets of PET. The relation between the surface density of the deposited material, morphology and resistivity was investigated for samples printed with a commercial Hewlett-Packard(HP)® printer and Microsoft Word® software. The amount of material deposited, i.e. surface density, was controlled using the print number in the same position and changing the gray scale used in the image formation. Changing the surface density of printed PEDOT:PSS, it is possible to produce a continuous film permeating the papers fibers. Sheet resistances obtained, when 7.0 mg cm−2 of PEDOT:PSS were deposited on the surfaces, were: (a) 413.2 kΩ/Sq for bond paper, (b) 5.6 kΩ/Sq for vegetable paper and (c) 2.3 kΩ/Sq for PET. The exponential dependence of sheet resistance with the surface density of printed material allows us to evaluate the strong influence of substrate roughness on PEDOT:PSS conductivity and to predict, for each one, conditions to minimize it. São Paulo State University (UNESP) School of Technology and Applied Sciences Campus Presidente Prudente São Paulo State University (UNESP) School of Technology and Applied Sciences Campus Presidente Prudente

Made available in DSpace on 2015-11-03T15:29:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-11-01. Added 1 bitstream(s) on 2015-11-04T10:16:12Z : No. of bitstreams: 1 S1516-14392014000600014.pdf: 3036693 bytes, checksum: 9c10b6735a0dbb7c9618b86666398c6d (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) INEO (Brazil) Thermal inkjet-printing of copper tetrasulfonated phthalocyanine (CuTsPc) films containing polyvinyl alcohol (PVA) plasticizer were used to fabricate flexible metal-insulator-semiconductor (MIS) capacitors using anodic aluminum oxide (Al2O3) as the insulating layer. The Al2O3 layer and printed CuTsPc+PVA films were characterized individually and in a MIS structure by electrical impedance spectroscopy. Capacitance-frequency and capacitance-voltage measurements revealed distinct contributions from CuTsPc and PVA on the device electrical response. From these measurements the semiconductor charge carrier mobility, mu, of 1.22x10(-4) cm(2) V-1 s(-1) and the doping density, N A, of 3.1x10(16) cm(-3) were calculated. It was observed a low-frequency electrical response, which was attributed to diffusional processes within the printed film arising from Na+ ions dissociated from the CuTsPc molecule. A simple equivalent circuit model was proposed to take this effect into account. Finally, the results shown here demonstrate the possibility to produce flexible organic electronic devices exploiting the semiconducting properties of water-soluble CuTsPc molecules using low-cost commercial printers. Sao Paulo State Univ UNESP, Fac Sci &Technol, Dept Phys Chem &Biol, Presidente Prudente, SP, Brazil Fed Inst Educ Sci &Technol Santa Catarina IFC, Araquari, SC, Brazil Sao Paulo State Univ UNESP, Fac Sci &Technol, Dept Phys Chem &Biol, Presidente Prudente, SP, Brazil

CONTEXTUALIZAÇÃO: O uso da eletromiografia de superfície (EMG-S) tem sido considerado como instrumento de avaliação quantitativa na síndrome da dor patelofemoral (SDPF). Tratamentos conservadores objetivam melhorar o alinhamento patelar, e a estimulação elétrica do músculo vasto medial oblíquo (VMO) tem sido considerada por ser seletiva e não causar irritação articular. OBJETIVO: Verificar o efeito de um programa de fortalecimento muscular com estimulação elétrica do VMO na SDPF por meio da capacidade de avaliação da EMG-S. MÉTODOS: Participaram deste estudo 10 mulheres jovens (idade: 23,1±4,9 anos; massa corporal: 66,8±14,0 kg; estatura: 1,63±6,9 cm; IMC: 25,1±5,6 kg/m²) com SDPF unilateral, as quais realizaram o teste funcional de subir degrau para captação da atividade eletromiográfica dos músculos VMO e vasto lateral (VL), antes e após um programa de estimulação elétrica do VMO. A eletroestimulação foi realizada três vezes por semana, durante seis semanas. Foram consideradas, para análise entre VMO e VL, as variáveis razão do tempo do início até o pico de ativação, razão da integral do sinal (teste t para amostras dependentes) e diferença de início de ativação (teste de Wilcoxon), com n��vel de significância de pBACKGROUND: The use of surface electromyography (SEMG) has been considered a tool for quantitative assessment of patellofemoral pain syndrome (PFPS). Conservative treatments aim to improve patellar alignment, and electrical stimulation of the vastus medialis obliquus (VMO) muscle has been considered effective because it is selective and does not cause joint irritation. OBJECTIVE: This study aims to investigate the efficiency of a muscle strengthening program with electrical stimulation of the VMO muscle in PFPS by SEMG. METHODS: A group of ten young women (age: 23.1±4.9 years; body mass: 66.8±14.0 kg; height: 1.63±6.9 cm; BMI: 25.1±5.6 kg/m²) with unilateral PFPS participated in the study. They performed the functional test of stair stepping to capture the electromyographic (EMG) activity of the VMO and vastus lateralis (VL) muscles, before and after a program of electrical stimulation of the VMO muscle. The electrical stimulation was performed three times per week for six weeks. For analysis between the VMO and VL muscles, we considered the variables: ratio of time of onset to peak of activation, ratio of the integrals of the signals (t-test for dependent samples), and difference between onsets of activation (Wilcoxon test), with significance level of p

Embora a análise no domínio da freqüência do sinal eletromiográfico (EMG) seja empregada na caracterização do processo de fadiga muscular localizada, sua aplicação, especificamente a da freqüência mediana (Fmed), é pouco explorada no âmbito esportivo. O objetivo do presente estudo foi verificar a viabilidade da aplicação do sinal EMG, através de sua análise no domínio da freqüência, como parâmetro para determinação e diferenciação no comportamento da fadiga muscular localizada. Dois grupos de sujeitos, um caracterizado como atletas (n =12) e outro como sedentários (n =12), foram submetidos a análises baseadas em procedimentos executados em três diferentes situações experimentais, todos envolvendo a modalidade de exercício isométrico: i) teste máximo para determinação da contração isométrica voluntária máxima (CIVM); ii) teste de fadiga, sustentado por 35 seg. a 80% da CIVM; iii) teste de recuperação, sustentado por 10 seg. a 80% da CIVM; neste ultimo foi monitorado o comportamento da Fmed nos três primeiros (Fmedi) e três últimos segundos (Fmedf) do sinal EMG no músculo tibial anterior durante o teste de fadiga. Durante os 10 segundos do teste de recuperação foi calculada a Fmed referente a todo o período (Fmedr). parâmetro utilizado no cálculo do índice de recuperação muscular (IRM). Os resultados apontam que a Fmedf apresentou valor menor em relação à Fmedi em ambos os grupos (p < 0,05). Quando comparado com o grupo de sedentários, o grupo de atletas apresentou valores maiores de Fmedi e Fmedf (p < 0,05). O valor médio e desvio-padrão do IRM para o grupo de atletas foram de 62,1% ± 28,7 e, para o grupo de sedentários, de 55,2% ± 27,8 (p > 0,05). Dessa forma, os resultados apresentados neste estudo permitem inferir a viabilidade na aplicação de parâmetros no domínio da freqüência do sinal EMG para a determinação e diferenciação do comportamento da fadiga muscular localizada.Although the analysis in the frequency domain of the Electromyographic Signal (EMG) has been used in the characterization of the localized muscular fatigue process, its application, specifically the Median Frequency (MF), is rarely explored in sports. The objective of this study was to verify the viability of the EMG signal application, through its frequency domain analysis, as a parameter for determination and differentiation of the behavior of localized muscle fatigue. Two groups of subjects, one characterized as athletes (n = 12) and the other as sedentary (n = 12), were submitted to analysis based on procedures from three different experimental situations, all involving isometric exercise modality: i) maximum test for determination of the Maximum Voluntary Isometric Contraction (MVIC); ii) fatigue test, 35 sec. sustained load of 80% of MVIC; iii) recovery test, 10 sec. sustained load of 80% of MVIC. In the latter, the MF behavior in the three first (Fmedi) and three last (Fmedf) seconds of the EMG signal of tibialis anterior muscle during the fatigue test have been monitored. During the 10 seconds of the recovery test, MF was calculated regarding the whole period (Fmedr); this parameter was used to calculate the Muscular Recovery Index (MRI). The results showed that Fmedf presented lower value in relation to Fmedi in both groups (p < 0.05). Additionally, the Fmedi and Fmedf values for the athlete group were higher in comparison to the sedentary group (p < 0.05). The MRI mean value and standard deviation for the athlete group were 62.1% ± 28.7 and for the sedentary group was 55.2% ± 27.8 (p > 0.05). Therefore, the results presented in this study allow inferring the viability in the application of the frequency domain parameters of the EMG signal for the determination and differentiation of localized muscle fatigue behavior.

Made available in DSpace on 2018-12-11T17:26:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) This paper reports on the analysis of dispersion in the imaginary part of impedance often observed at low frequencies in a variety of systems. The experimental data were obtained with an electrolytic cell containing KCl aqueous solution in the frequency range from 0.1 mHz to 10 MHz, where the use of ultra-low frequencies helps clarify the analysis of the imaginary impedance dispersion. It is shown that the low frequency dispersion described in the literature is the tail of a relaxation peak located at f ≅ 20 mHz. This ultra-low frequency dispersion peak is analyzed with a Cole-Cole impedance element, being associated with the electric double layer at the metal-electrolyte interface. Quantitative information can be extracted for the double layer, including its thickness (∼1 nm) and electrical resistivity (∼50 GΩm). Instituto de Física de São Carlos USP Faculdade de Ciências e Tecnologia UNESP Faculdade de Ciências e Tecnologia UNESP

The generation of physical movement in animals involves the activation and control of muscle forces. Understanding the mechanisms behind force generation and control is essential for professionals who work to promote health. The human body can be represented as a system of articulated segments in static or dynamic balance. Within this system, movement can arise from internal forces acting outside the joint axis, causing angular displacement of these segments, or by forces external to the body. Knowledge of the contribution of muscle forces to joint position and movement is of great importance for the study of muscle activity during exercise and also for understanding the coordination of muscle activities during functional movement. However, muscles forces cannot be easily measured in vivo; rather, they must be assessed, calculated or modeled (Amadio & Duarte, 1996; Amadio & Barbanti 2000). Closely associated with the generation of force by a muscle, is the generation of an electrical signal that can be observed by placing electrodes on the skin surface to detect underlying electrical activity displaying the associated waveform on a computer monitor. This process is called electromyography (EMG) and the waveform is the electromyogram. The assumption that there is an association between EMG and underlying muscle forces is the basis for many applications of EMG, allowing inferences regarding various aspects of muscle physiology. However, it is not possible to measure muscle force directly using EMG. Since 1952 there have been studies that show some cases where there is a linear relationship between force and EMG (Lippold, 1952), however this relationship is not always simple and linear. In recent years methods for detecting and processing EMG signals have been refined considerably, with the availability of better equipment, tools, mathematical, statistical and computational techniques. Although the determination of muscle strength using EMG measurements has also evolved, it has not yet fully exploited the technological potential available. In this chapter, we describe a practical approach to the quantitative evaluation of muscle force through analysis of the EMG signal.

Made available in DSpace on 2013-08-12T18:24:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-01 Made available in DSpace on 2013-09-30T18:09:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:22:58Z No. of bitstreams: 1 S0004-282X2010000400016.pdf: 154428 bytes, checksum: 42a136afc3e6d9f1f2df075aa02f805e (MD5) Made available in DSpace on 2014-05-20T13:22:58Z (GMT). No. of bitstreams: 1 S0004-282X2010000400016.pdf: 154428 bytes, checksum: 42a136afc3e6d9f1f2df075aa02f805e (MD5) Previous issue date: 2010-08-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Many authors have studied physical and functional changes in individuals post-stroke, but there are few studies that assess changes in the non-plegic side of hemiplegic subjects. This study aimed to compare the electromyographic activity in the forearm muscles of spastic patients and clinically healthy individuals, to determine if there is difference between the non-plegic side of hemiplegics and the dominant member of normal individuals. 22 hemiplegic subjects and 15 clinically healthy subjects were submitted to electromyography of the flexor and extensor carpi ulnaris muscles during wrist flexion and extension. The flexor muscles activation of stroke group (average 464.6 u.n) was significantly higher than the same muscles in control group (mean: 106.3 u.n.) during the wrist flexion, what shows that the non affected side does not present activation in the standart of normality found in the control group. UNESP, LAFAMH, FCT, Dept Fisioterapia, BR-19060900 Presidente Prudente, SP, Brazil UNESP, Lab Phys Therapy Appl Human Movement, BR-19060900 Presidente Prudente, SP, Brazil Univ São Paulo, Postgrad Program Interunits Bioingn, São Carlos, SP, Brazil UNESP, LAFAMH, FCT, Dept Fisioterapia, BR-19060900 Presidente Prudente, SP, Brazil UNESP, Lab Phys Therapy Appl Human Movement, BR-19060900 Presidente Prudente, SP, Brazil FAPESP: 06/51155-0

RESUMO Introdução: Ajustes antecipatórios (pré-ativação) dos músculos profundos do tronco aumentam a estabilidade lombopélvica. Estudos prévios demonstram que indivíduos assintomáticos podem apresentar atrasos no início de ativação muscular e alterações físico-funcionais. No entanto, não foram encontrados estudos que tenham verificado se testes físico-funcionais (TFF) são capazes de identificar alteração no início de ativação dos músculos estabilizadores lombopélvicos. Objetivo : Verificar os níveis de sensibilidade, especificidade e acurácia de um conjunto de testes de avaliação da capacidade física funcional para detectar alterações na pré-ativação dos músculos transverso do abdome/oblíquo interno (TrA/OI) e multífido lombar (ML) durante o teste de movimento rápido de flexão do ombro (TMRFO). Método : Participaram do estudo 27 voluntários assintomáticos para dor lombar, com média de idade de 23,8 anos (desvio padrão: 2,2), e que foram submetidos aos TFF e TMRFO para determinação do início da ativação dos músculos profundos do tronco por meio da eletromiografia de superfície. Foi verificada sensibilidade e especificidade e análise da acurácia através da curva ROC (Receiver Operating Characteristic) e teste de qui-quadrado para comparações entre porcentagens (p < 0,05) . Resultados : A "pré-ativação" foi a condição que ocorreu com maior frequência no grupo como um todo, bem como em ambos os gêneros, com exceção do TrA/OI no gênero feminino (χ2 = 0,28/P = 0,58). Entre todos os TFF aplicados, o de enrolamento repetitivo do tronco apresentou maior valor de sensibilidade, especificidade e área sob a curva ROC (0,75; 0,73; 0,74, respectivamente) . Conclusão : Entre os TFF avaliados, o de enrolamento repetitivo do tronco mostrou níveis aceitáveis de acurácia para identificar alterações na ativação da musculatura estabilizadora lombopélvica em voluntários assintomáticos para dor lombar. Assim, o teste de enrolamento repetitivo do tronco pode ser utilizado na clínica para predizer alterações na ativação dos músculos profundos do tronco. ABSTRACT Introduction: Anticipatory adjustments (pre-activation) of the deep trunk muscles increase lumbopelvic stability. Previous studies have shown that asymptomatic individuals may experience delays in the start of muscle activation, as well as functional physical alterations. However, there are no studies that assess whether physical and functional tests (PFT) are able to identify changes in early activation of the lumbopelvic stabilizer muscles. Objective: To assess the levels of sensitivity, specificity and accuracy of a set of physical and functional performance tests to detect changes in anticipatory activation of the transversus abdominis/internal oblique muscles (TrA/OI) and lumbar multifidus (ML) during a task of fast shoulder flexion movements (FSFM) . Method: Twenty-seven volunteers, asymptomatic for low back pain, with a mean age of 23.8 (Standard deviation: 2.2) years, participated in the study. They were submitted to PFT and FSFM to determine the initial activation time of the deep trunk muscles through surface electromyography. Sensitivity and specificity were determined, and accuracy was analyzed by the ROC (Receiver Operating Characteristic) curve and chi-square test for comparisons between percentages (p