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OBJECTIVE: Conical orthopedic drill bits may have the potential to improve the stabilization of orthopedic screws. During perforations, heat energy is released, and elevated temperatures could be related to thermal osteonecrosis. This study was designed to evaluate the thermal behavior of an experimental conical drill bit, when compared to the conventional cylindrical drill, using polyurethane blocks perforations. RESULTS: The sample was divided into two groups, according to the method of drilling, including 25 polyurethane blocks in each: In Group 1, perforations were performed with a conventional orthopedic cylindrical drill; while in Group 2, an experimental conical drill was used. No statistically significant difference was observed in relation to the maximum temperature (MT) during the entire drilling in the groups, however the perforation time (PT) was slightly longer in Group 2. Each drill bit perforated five times and number of perforations was not correlated with a temperature increase, when evaluated universally or isolated by groups. The PT had no correlation with an increase in temperature when evaluating the perforations universally (n = 50) and in Group 1 alone; however, Group 2 showed an inversely proportional correlation for these variables, indicating that, for the conical drill bit, drillings with longer PT had lower MT.

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Arsenic compounds have been used as therapeutic alternatives for several diseases including cancer. In the following work, we obtained arsenic nanoparticles (AsNPs) produced by an anaerobic bacterium from the Salar de Ascotán, in northern Chile, and evaluated their effects on the human oral squamous carcinoma cell line OECM-1. Resazurin reduction assays were carried out on these cells using 1-100 µM of AsNPs, finding a concentration-dependent reduction in cell viability that was not observed for the non-tumoral gastric mucosa-derived cell line GES-1. To establish if these effects were associated with apoptosis induction, markers like Bcl2, Bax, and cleaved caspase 3 were analyzed via Western blot, executor caspases 3/7 via luminometry, and DNA fragmentation was analyzed by TUNEL assay, using 100 µM cisplatin as a positive control. OECM-1 cells treated with AsNPs showed an induction of both extrinsic and intrinsic apoptotic pathways, which can be explained by a significant decrease in P-Akt/Akt and P-ERK/ERK relative protein ratios, and an increase in both PTEN and p53 mRNA levels and Bit-1 relative protein levels. These results suggest a prospective mechanism of action for AsNPs that involves a potential interaction with extracellular matrix (ECM) components that reduces cell attachment and subsequently triggers anoikis, an anchorage-dependent type of apoptosis.

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OBJECTIVE: The objective of this study is to compare drilling variables and torsional mechanical properties of rabbit femora after bicortical drilling with a 1.5-mm standard surgical drill bit, acrylic drill bit, and K-wire. SAMPLES: 24 pairs of rabbit femora. METHODS: After drilling under controlled axial displacement rate, each bone was biaxially loaded in compression followed by rapid external torsion to failure. Maximum axial thrust force, maximum drill torque, integral of force and displacement, change in temperature, maximum power spectral density of the torque signal, torque vibration, and torque and angle at the yield and failure points were collected. Pre- and postyield stiffness, yield and failure energies, and postyield energy were calculated. RESULTS: The work required to drill through the cis- and transcortices (integral of force and displacement) was greater for the K-wire, followed by the acrylic and then standard drill bits, respectively. The K-wire demonstrated higher maximum torque than the drill bits at the ciscortex, and the force of drilling was significantly greater. The vibration data was greater with the acrylic and standard drill bits than the K-wire. There was no difference in torsional strength between drilling types. CLINICAL RELEVANCE: Mechanical differences exist between different drill bits and K-wire and demonstrate that the K-wire is overall more damaging than the surgical drill bit.

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Relay-assisted wireless communications, where both the relay and the final destiny employ diversity-combining techniques, represent a compelling strategy for improving the signal-to-noise ratio (SNR) for mobile terminals, mainly at millimeter-wave (mmWave) frequency bands. In this sense, this work considers a wireless network that employs a dual-hop decode-and-forward (DF) relaying protocol, in which the receivers at the relay and at the base station (BS) use an antenna array. Moreover, it is considered that the received signals are combined at reception using equal-gain-combining (EGC). Recent works have enthusiastically employed the Weibull distribution so as to emulate the small-scale fading behavior in mmWave frequencies, which also motivates its use in the present work. For this scenario, exact and asymptotic expressions for the system's outage probability (OP) and average bit error probability (ABEP) are derived in closed form. Useful insights are gained from these expressions. More precisely, they illustrate how the system and fading parameters affect the performance of the DF-EGC system. Monte Carlo simulations corroborate the accuracy and validity of the derived expressions. Furthermore, the mean achievable rate of the considered system is also evaluated via simulations. Useful insights regarding the system performance are obtained from these numerical results.

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ABSTRACT Medical image security is acquiring its importance to preserve the integrity and confidentiality of information (medical data) from malicious users given its importance in timely and successful diagnosis. In this context, several techniques have been developed to protect medical images, such as encryption, data hiding, image tagging, application of Hash algorithms, etc. This paper proposes a technique to cipher medical images by adding the metadata inside a cover image, based on extended visual cryptography as well as the inclusion of a Hash-like function to verify the integrity of the image and the metadata once they are recovered. The method proposed in this work is implemented using medical images with a grayscale resolution of [0,4095] that is a depth of 12 bits/pixel and color images with 24 bits/pixel depth. Experimental results prove the effectiveness of the proposed method in the task of secure exchange of medical images by allowing higher hiding capability, lower distortion in the visual quality of the image with the hidden medical data, as well as a means to verify the integrity of the sent data, compared to state-of-the-art.

RESUMEN La seguridad de imágenes médicas está incrementando su importancia para preservar la integridad y la confidencialidad de la información (datos médicos), frente a usuarios malintencionados dada su importancia en el diagnóstico oportuno y acertado. En este contexto, se han desarrollado varias técnicas para proteger las imágenes médicas, como el cifrado, la ocultación de datos, el etiquetado de imágenes, la aplicación de algoritmos Hash, etc. Este trabajo propone una técnica para cifrar imágenes médicas añadiendo los metadatos dentro de una imagen de cubierta, basada en la criptografía visual extendida, así como la inclusión de una función tipo Hash para comprobar la integridad de la imagen y los metadatos una vez estos sean recuperados. El método propuesto en este trabajo se implementa utilizando imágenes médicas con una resolución en escala de grises de [0,4095] es decir una profundidad de 12 bits/ píxel e imágenes en color con 24 bits/píxel de profundidad. Los resultados experimentales demuestran la eficacia del método propuesto en la tarea de transmisión segura de imágenes médicas permitiendo una mayor capacidad de ocultamiento, una menor distorsión en la calidad visual de la imagen con los datos médicos ocultos, así como un medio para comprobar la integridad de los datos enviados, en comparación con los artículos publicados.

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Large intelligent surfaces (LIS) are a new trend to achieve higher spectral efficiency and signal-to-noise ratio in mobile communications. For this reason, this paper proposes metrics to analyze the performance of systems with multiple antennas aided by LIS and derive the spectral efficiency, secrecy outage probability, and bit error probability in an environment with Nakagami-m distributed fading. In addition to an eavesdropper, there is a single-antenna user, an array of antennas at the transmitter side and the possibility of a direct link between transmitter and receiver. This study assumes that the LIS performs non-ideal phase cancellation leading to a residual phase error that follows a Von Mises distribution, and shows that the resulting channel can be accurately approximated by a Gamma distributed SNR whose parameters are analytically derived. From these formulas, it is possible to evaluate the effect of the strength of the line-of-sight link by varying the Nakagami parameter, m.

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We study here the vehicle-to-vehicle (V2V) visible light communication (VLC) between two cars moving along different roadway scenarios: (i) a multiple-lane rectilinear roadway and (ii) a multiple-lane curvilinear roadway. Special emphasis was given to the implementation of full-duplex (FD) cooperative communication protocols to avoid communication disruption in the absence of a line-of-sight (LOS) channel. Importantly, we found that the cooperative FD V2V-VLC is promising for avoiding communication disruptions for cars traveling in realistic curvilinear roadways. Results in this work can be easily extended to the case of vehicle-to-infrastructure (V2I), which can also be promising in cases of low-car-density environments.

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Sample preparation of complex matrices, like food samples, continues to be a challenge demanding great effort for improvements. In this study, a new technique named balls-in-tube matrix solid-phase dispersion (BiT-MSPD) is proposed based on a simplification of the conventional MSPD technique being all sample preparation performed directly in a closed extraction tube with the assistance of steel balls. An innovative method using BiT-MSPD was successfully established for the determination of 133 pesticide residues in apple, peach, pear and plum by ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS). Several sorbents were evaluated as solid support in different proportions with the sample. The homogenization step using mortar, glass rod or steel balls, with methanol and acetonitrile as extraction solvent, was evaluated. Vortex and ultrasound assisted extractions were also tested. Best results were obtained with C18, homogenization with steel balls, acetonitrile as solvent and ultrasound assisted extraction. Validation presented adequate trueness and precision results for the evaluated pesticides with recovery results ranging from 72 to 113% and RSD ≤ 17%. Practical limit of detection (LOD) and quantification (LOQ) for the compounds were 3 and 10 µg kg-1, respectively. The developed method proved to be easier and faster to perform than the MSPD, considering that extraction and clean-up are performed in the same tube without the need to transfer to cartridges, recipients or to use a separate clean-up step. The proposed BiT-MSPD technique was successfully applied to fruit samples and has great potential to be applied in other matrices, like cereals and meat, since the steel balls promote an efficient sample dispersion and extraction of pesticides. The BiT-MSPD permit a fully automation of the entire sample preparation step.

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INTRODUCCIÓN: El trastorno del espectro autista (TEA) es un desorden neurobiológico altamente prevalente, cuyo diagnóstico clínico es un desafío constante. OBJETIVOS: Describir el perfil clínico, en una cohorte de niños con TEA desde su derivación al especialista hasta la realización de un test diagnóstico. PACIENTES Y MÉTODO: Estudio descriptivo desde los primeros síntomas pesquisados por la madre, hasta la certificación diagnóstica de una serie de 50 niños, diagnosticados clínicamente con TEA entre 2012-2016. Se incluyeron niños de 3 a 10 años al momento del Test ADOS-G, con lenguaje de al menos una palabra. Los niños fueron evaluados neuropsicológicamente (funcionali dad, intelectualidad y test ADOS). Comparamos las medianas de edad al diagnóstico neurológico, según carga de sintomatología autista y nivel cognitivo. RESULTADOS: El test ADOS corroboró un TEA en 44 niños (88%), 93,1% eran varones. La edad promedio al diagnóstico clínico y test ADOS fue 48,2 ± 18,3 y 62,6 ± 23,3 meses. La consulta neurológica en el 72% de los casos fue motivación parental/educador por síntomas como trastorno interacción social y retraso de lenguaje. El 34,1; 47,7 y 18,2% tenían sintomatología autista leve, moderada y severa respectivamente. En 5 de 27 ni ños en los que se realizó la evaluación neuropsicológica se detectó déficit cognitivo. La mediana de edad al diagnóstico fue significativamente menor en niños con sintomatología autista grave vs leve- moderada (p 0,024). CONCLUSIÓN: La sintomatología autista determina la precocidad de consulta, por lo que es necesario orientar a la población general, educadores y personal de salud, respecto a estos síntomas.

INTRODUCTION: Autism Spectrum Disorder (ASD) is a neurobiological disorder of high prevalence, whose clinical diagnosis is a constant challenge. OBJECTIVES: To describe the clinical profile in a co hort of children with ASD from referral to the specialist to a diagnostic test. PATIENTS AND METHOD: Descriptive study from the first symptoms perceived by the mother to the diagnostic confirmation of a series of 50 consecutive cases, which were clinically diagnosed with ASD between 2012 and 2016. Children aged between 3 to 10 years at the time of the ADOS-G test and language of at least one word were included. The children were evaluated neuropsychologically (functionality, intellectuality and ADOS test). We compared the median age to the neurological diagnosis, according to the autistic symptomatology and cognitive level. RESULTS: The ADOS test corroborated an ASD in 44 children (88%), 93.1% were males. The average age at clinical diagnosis and ADOS test was 48.2 ± 19.3 and 62.6 ± 23.3 months. The neurological consultation in 72% of cases was parental/educator initiative due to symptoms such as social interaction disorder and language delay. The autistic symptomato logy was mild, moderate and severe in 34.1, 47.7 and 18.2% respectively. In five of 27 children who were neuropsychologically evaluated cognitive deficits were detected. The median age at diagnosis was significantly lower in children with severe autism symptoms vs the ones with mild-moderate symptoms (p-value 0.024). CONCLUSION: Autistic symptoms determine the early consultation; the refore, it is necessary to guide the general and educational population as well as health professionals regarding these symptoms.

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We propose an approach for the synchronization of video streams using correntropy. Essentially, the time offset is calculated on the basis of the instantaneous transfer rates of the video streams that are extracted in the form of a univariate signal known as variable bit-rate (VBR). The state-of-the-art approach uses a window segmentation strategy that is based on consensual zero-mean normalized cross-correlation (ZNCC). This strategy has an elevated computational complexity, making its application to synchronizing online data streaming difficult. Hence, our proposal uses a different window strategy that, together with the correntropy function, allows the synchronization to be performed for online applications. This provides equivalent synchronization scores with a rapid offset determination as the streams come into the system. The efficiency of our approach has been verified through experiments that demonstrate its viability with values that are as precise as those obtained by ZNCC. The proposed approach scored 81 % in time reference classification against the equivalent 81 % of the state-of-the-art approach, requiring much less computational power.

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La introducción de nuevos cultivares de guayabo (Psidium guajava L.) amerita su propagación masiva, lo cual solo puede ser satisfecho mediante la micropropagación. Sin embargo la micropropagación convencional dejó de ser económicamente eficiente, debido al uso de agentes gelificantes y el elevado número de operaciones manuales, por esta razón se planteó en esta investigación, generar una metodología que permita disminuir los costos de producción por la exclusión del gelificante en los medios de cultivo, evaluando los sistemas de inmersión temporal (SIT) en la multiplicación in vitro de guayabo. Para lo cual, se evaluó el efecto del cultivo en SIT, se comparó los SIT tipo BIT® y RITA® y se evaluó el tiempo (1 y 2 min) y frecuencia (3 y 4 veces/día) de inmersión. Luego de seis semanas de cultivo se evaluó: número de brotes (NB), numero de nudos (NN), longitud de brote (LB) y coeficiente de multiplicación (CM). Con el empleo de SIT se logró valores superiores para NB (2,17), NN (3,5), LB (10,7 mm) y CM (2,8). En la comparación entre SIT tipo RITA y BIT, valores superiores se obtuvieron con el RITA® para NB (3,8), NN (3,8), LB (16,6 mm) y CM (10,4). Se determinó que con 2 min de inmersión se logró los mayores valores de NB (3,7), NN (13,4), LB (15,3 mm) y con 2 min de inmersión 3-4 veces/día el mayor CM (9,4 y 10,4). Se concluye que el cultivo en RITA® en la multiplicación favoreció crecimiento y la proliferación de brotes de guayabo.

The introduction of new cultivars of guava (Psidium guajava L.) deserves its mass propagation, which can only be satisfied by micropropagation. However conventional micropropagation stopped being economically efficient due to the use of gelling agents and the high number of manual operations. For this reason was considered in this research, generate a methodology to reduce production costs by exclusion of gelling in culture media, assessing temporary immersion systems (TIS) in the in vitro multiplication of guava. For which, the effect of the culture way was evaluated in TIS, type TIB® and RITA® compared the TIS and was evaluated the time (1 and 2 min) and frequency (3 and 4 times / day) of immersions. After six weeks of culture were evaluated: shoots number (NS), nodes number (NN), shoot length (SL) and multiplication rate (MR). With the use of TIS higher values for NS (2.17), NN (3.5), SL (10.7 mm) and MC (2.8) was achieved. When comparing RITA® and TIB, higher values were obtained with the RITA® for NS (3.8), NN (3.8), SL (16.6 mm) and MC (10.4). It was determined that 2 min of immersion with the highest values of NS (3.7), NN (13.4), SL (15.3 mm) and 2 min immersion 3-4 times/day achieved the highest MC (9.4 and 10.4). We conclude that the RITA® culture favored the multiplication in growth and proliferation of shoots of guava.

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The objective of this trial was to evaluate the behavior ingestive of crossbred heifers and chemical characteristics of the material from two clones of dwarf elephant grass (BRS Kurumi and CNPGL 01/03/00) submitted to different management strategies through sampling of forage (whole plant extrusa and manual hand plucking. The experiment was conducted at Embrapa Dairy Cattle, Coronel Pacheco, MG. We used a completely randomized design with factorial (2x2x2) with three replications. The treatments consisted of two clones of elephant grass (BRS Kurumi and CNPGL 01/03/00), two light interception at the entrance of the animals (90 and 95%) and two heights of post-grazing residue (30 and 50 cm) with three replications. The chemical analysis showed that the methodology manual grazing simulation enables an acceptable estimate of the forage selected by grazing animals and the sampling of the whole plant is not selected by the animal diet. To harvest extrusa rate evaluation and mass bit, fractions and chemical composition of the plant of the ingested material was taken. Characteristics, structural and nutritional value of clone BRS Kurumi facilitated greater forage intake by the animal, suggesting its use in grazing systems.(AU)

Este trabalho foi realizado com o objetivo de avaliar o comportamento ingestivo de novilhas mestiças e as características químicas da forragem de dois clones de capim-elefante anão (BRS Kurumi e CNPGL 00-1-3) submetidos a diferentes estratégias de manejo por meio de métodos de amostragem da forragem (planta inteira, extrusa e simulação manual de pastejo. O experimento foi conduzido na Embrapa Gado de Leite, em Coronel Pacheco, MG.). Utilizou-se o delineamento inteiramente casualizado, num esquema fatorial (2x2x2), com três repetições cada. Os tratamentos consistiram dois clones de capim-elefante (BRS Kurumi e CNPGL 00-3-1), duas interceptações luminosas (IL) na entrada dos animais (90 e 95%) e duas alturas de resíduo pós-pastejo (30 e 50 cm), com três repetições. As análises bromatológicas demonstraram que a metodologia da simulação manual de pastejo possibilita uma estimativa aceitável da forragem selecionada pelos animais em pastejo e a amostragem de planta inteira não representa a dieta selecionada pelo animal. Para a colheita de extrusa foi feita avaliação da taxa e massa do bocado, frações da planta e composição química da forragem ingerida. As características, estruturais e valor nutritivo do clone BRS Kurumi facilitou maior aporte de forragem pelo animal, o que sugere seu uso em sistema de pastejo.(AU)

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The study was conducted to compare different methodologies for evaluation of ingestive behavior of heifers supplemented in grazing. The experiment was conducted at Princesa do Mateiro farm, Ribeirao do Largo, Bahia. Were used 30 heifers with blood level 5/8 Guzera milk lineage and 3/8 Holstein, with an average of 18 months of age and body weight of 187 ± 13.1 kg. The treatments were: Duration of avaliation (24, 12 and eight hours) of observation intervals (10, 20 and 30 minutes); repetitions for observation (three, two and one) shifts of observation (two and one). The behavior evaluation was performed on day 25th, 26th, 27th and 28th of each period, then a total of four ratings. The percentage of grazing activity on the duration of 8h and 12h evaluation differed from the standard evaluation period of 24 hours (P 0.05). The duration of evaluation tests (8h and 12h) showed differences in duration of 24 hours to evaluate the percentages of rumination (P 0.05). As for the percentage of other activities, no difference was observed between duration evaluation and standard tests (P>0.05). For grazing time, rumination, feeding at the trough, other activities, total feeding and total chewing have not been verified statistical differences between the ranges of observations 20 and 30 minutes compared with 10 minutes (P 0.05). The duration of evaluation of 24 hours is recommend for evaluation of ingestive behaviorin terms of nutritional and metabolic parameters, as other promote distortion of the data as a function ofthe intensity of activities throughout the day.(AU)

O estudo foi realizado com o objetivo de comparar diferentes metodologias para avaliação do comportamento ingestivo de novilhas suplementadas a pasto. O experimento foi conduzido na fazenda Princesa do Mateiro, município de Ribeirão do Largo, Bahia. Foram utilizadas 30 novilhas com grau de sangue 5/8 Guzerá linhagem leiteira e 3/8 Holandesa, com média de 18 meses de idade e peso corporal médio de 187 ± 13,1 kg. Os tratamentos foram: Duração de avaliação (24, 12 e oito horas); Intervalos de observação (10, 20 e 30 minutos); Repetições por observação (três, duas e uma); Turnos de observação (dois e um). A avaliação do comportamento foi realizada no 25º, 26º, 27º e 28º dia de cada período, totalizando então quatro avaliações. Os percentuais da atividade de pastejo da duração de avaliação 8h e 12h diferiram da duração de avaliação padrão de 24h (P 0,05). A duração de avaliação em testes (8h e 12h) apresentou diferenças da duração de avaliação de 24 horas para os percentuais de ruminação (P 0,05). Já para os percentuais de outras atividades, não foi verificado diferenças entre a duração de avaliação em testes e a padrão (P>0,05). Para o tempo de pastejo, ruminação, alimentação no cocho, outras atividades, alimentação total e mastigação total não foram verificados diferenças estatísticas entre os intervalos de observações 20 e 30 minutos quando comparados com o de 10 minutos (P>0,05).A duração de avaliação de 24 horas é a recomendada para avaliação do comportamento ingestivo emtermos de parâmetros nutricionais e metabólicos, pois as demais promovem distorção dos dados emfunção da variação da intensidade das atividades ao longo do dia.(AU)

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The study was conducted to compare different methodologies for evaluation of ingestive behavior of heifers supplemented in grazing. The experiment was conducted at Princesa do Mateiro farm, Ribeirao do Largo, Bahia. Were used 30 heifers with blood level 5/8 Guzera milk lineage and 3/8 Holstein, with an average of 18 months of age and body weight of 187 ± 13.1 kg. The treatments were: Duration of avaliation (24, 12 and eight hours) of observation intervals (10, 20 and 30 minutes); repetitions for observation (three, two and one) shifts of observation (two and one). The behavior evaluation was performed on day 25th, 26th, 27th and 28th of each period, then a total of four ratings. The percentage of grazing activity on the duration of 8h and 12h evaluation differed from the standard evaluation period of 24 hours (P 0.05). The duration of evaluation tests (8h and 12h) showed differences in duration of 24 hours to evaluate the percentages of rumination (P 0.05). As for the percentage of other activities, no difference was observed between duration evaluation and standard tests (P>0.05). For grazing time, rumination, feeding at the trough, other activities, total feeding and total chewing have not been verified statistical differences between the ranges of observations 20 and 30 minutes compared with 10 minutes (P 0.05). The duration of evaluation of 24 hours is recommend for evaluation of ingestive behaviorin terms of nutritional and metabolic parameters, as other promote distortion of the data as a function ofthe intensity of activities throughout the day.

O estudo foi realizado com o objetivo de comparar diferentes metodologias para avaliação do comportamento ingestivo de novilhas suplementadas a pasto. O experimento foi conduzido na fazenda Princesa do Mateiro, município de Ribeirão do Largo, Bahia. Foram utilizadas 30 novilhas com grau de sangue 5/8 Guzerá linhagem leiteira e 3/8 Holandesa, com média de 18 meses de idade e peso corporal médio de 187 ± 13,1 kg. Os tratamentos foram: Duração de avaliação (24, 12 e oito horas); Intervalos de observação (10, 20 e 30 minutos); Repetições por observação (três, duas e uma); Turnos de observação (dois e um). A avaliação do comportamento foi realizada no 25º, 26º, 27º e 28º dia de cada período, totalizando então quatro avaliações. Os percentuais da atividade de pastejo da duração de avaliação 8h e 12h diferiram da duração de avaliação padrão de 24h (P 0,05). A duração de avaliação em testes (8h e 12h) apresentou diferenças da duração de avaliação de 24 horas para os percentuais de ruminação (P 0,05). Já para os percentuais de outras atividades, não foi verificado diferenças entre a duração de avaliação em testes e a padrão (P>0,05). Para o tempo de pastejo, ruminação, alimentação no cocho, outras atividades, alimentação total e mastigação total não foram verificados diferenças estatísticas entre os intervalos de observações 20 e 30 minutos quando comparados com o de 10 minutos (P>0,05).A duração de avaliação de 24 horas é a recomendada para avaliação do comportamento ingestivo emtermos de parâmetros nutricionais e metabólicos, pois as demais promovem distorção dos dados emfunção da variação da intensidade das atividades ao longo do dia.

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The objective of this trial was to evaluate the behavior ingestive of crossbred heifers and chemical characteristics of the material from two clones of dwarf elephant grass (BRS Kurumi and CNPGL 01/03/00) submitted to different management strategies through sampling of forage (whole plant extrusa and manual hand plucking. The experiment was conducted at Embrapa Dairy Cattle, Coronel Pacheco, MG. We used a completely randomized design with factorial (2x2x2) with three replications. The treatments consisted of two clones of elephant grass (BRS Kurumi and CNPGL 01/03/00), two light interception at the entrance of the animals (90 and 95%) and two heights of post-grazing residue (30 and 50 cm) with three replications. The chemical analysis showed that the methodology manual grazing simulation enables an acceptable estimate of the forage selected by grazing animals and the sampling of the whole plant is not selected by the animal diet. To harvest extrusa rate evaluation and mass bit, fractions and chemical composition of the plant of the ingested material was taken. Characteristics, structural and nutritional value of clone BRS Kurumi facilitated greater forage intake by the animal, suggesting its use in grazing systems.

Este trabalho foi realizado com o objetivo de avaliar o comportamento ingestivo de novilhas mestiças e as características químicas da forragem de dois clones de capim-elefante anão (BRS Kurumi e CNPGL 00-1-3) submetidos a diferentes estratégias de manejo por meio de métodos de amostragem da forragem (planta inteira, extrusa e simulação manual de pastejo. O experimento foi conduzido na Embrapa Gado de Leite, em Coronel Pacheco, MG.). Utilizou-se o delineamento inteiramente casualizado, num esquema fatorial (2x2x2), com três repetições cada. Os tratamentos consistiram dois clones de capim-elefante (BRS Kurumi e CNPGL 00-3-1), duas interceptações luminosas (IL) na entrada dos animais (90 e 95%) e duas alturas de resíduo pós-pastejo (30 e 50 cm), com três repetições. As análises bromatológicas demonstraram que a metodologia da simulação manual de pastejo possibilita uma estimativa aceitável da forragem selecionada pelos animais em pastejo e a amostragem de planta inteira não representa a dieta selecionada pelo animal. Para a colheita de extrusa foi feita avaliação da taxa e massa do bocado, frações da planta e composição química da forragem ingerida. As características, estruturais e valor nutritivo do clone BRS Kurumi facilitou maior aporte de forragem pelo animal, o que sugere seu uso em sistema de pastejo.

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The present study was based on the hypothesis that a limited amount of information can be simultaneously processed in working memory. The main objective was to determine the capacity of working memory under experiment conditions and express it in terms of bits of information. The bit values of the selected objects used in the experiment were determined using Shannon's formula. The objects were presented to the participants as a set of charts. Each chart presented a four-element object with a particular bit value. The elements constituted commonly known signs, with no difficulty in perception. The efficiency of object recollection from working memory decreased as the bit value of the object increased. In each of the experiments, the bit value of the recollected information oscillated between 26.7 and 31.9. The present results did not confirm sex differences in working memory function...

Assuntos

RESUMO

Hace algunos años, se ha publicado el nuevo Test Gestáltico de Bender, segunda versión (Bender-II). Esta nueva versión usa el Sistema de Calificación Global (SCG) para obtener los puntajes, que enfatiza la reproducción exacta de los diseños; junto con otros cambios estructurales, consiste en la mayor modificación realizada al Test de Bender para evaluar la habilidad visomotora en varias etapas del desarrollo humano. Pero aún hay pocas investigaciones que han estudiado su funcionamiento psicométrico en muestras hispanas y especialmente el error de medición en el procedimiento de la calificación. Se investigó el efecto de la variabilidad de la calificación del nuevo Bender-II sobre su validez de constructo con una medida de inteligencia. Se administraron el Bender-II y el Test Breve de Inteligencia de Kaufman (K-BIT) a 60 niños preescolares, y tres calificadores calificaron las figuras reproducidas mediante procedimientos estandarizados y el SCG. El análisis comparó las correlaciones obtenidas por cada calificador entre los puntajes del Bender-II y del K-BIT. Se halló que la variabilidad de los puntajes proveniente de la interpretación del SCG afectó moderadamente las correlaciones con el puntaje total y de las subescalas del K-BIT. Un calificador fue menos confiable y sus puntajes mostraron al menos 5% menos variancia compartida al compararlo con los otros calificadores. Se concluye que la interpretación de la validez se puede distorsionar aun cuando el error de medición es moderado pues interaccionan con otras fuentes de error. Esto sugiere que se debe garantizar un buen acuerdo en la calificación de pruebas que requieran juicio.

Although the impact of the measurement error in the accuracy of the classification of subjects and validity correlations is theoretically established, in a practical situation has not been explored the degree of impact on the new Bender-II (Brannigan & Decker, 2003). The practical situation of assessment is that which occurs in the professional context, in which one or more examiners of an assessment team assessing children in a particular institution. The new Bender-II has substantial modifications in its structure and functioning, making it different from the original instrument proposed by Bender (1938, 1946). Structural changes consisted in more of items (16 designs), complementary tests (fine motor and visual perception) and two major tests (Visual Constructive Memory and Visual Motor), the rating method Global Scoring System (GSS) and standardized record sheet for the child's behavior during the test administration. The GSS was created ad hoc for the Bender-II, and it is a method that emphasizes the exact reproduction of the designs; its origin is in the original gestalt approach of Bender. Main studies have been published in the manual (Brannigan & Decker, 2003), and subsequent studies have used the American standardization sample. However, in non-immigrant Hispanic population, to date there are some unpublished and published only one (Merino, 2012); therefore, it is not known how generalizable the findings and psychometric properties obtained in the American standardization sample are. The aim of the study was to examine the effect of the variability of the scoring of designs of the new Bender-II on construct validity with a measure of intelligence. The Bender-II and Kaufman Brief Intelligence Test (K-BIT - Kaufman, A. S. & Kaufman, A. L., 1994) was administered to 60 preschool children (between 4 and 5 years, 33 girls), and three scorers rated the designs reproduced, by standardized procedures and GSS. The analysis consisted of two steps: first, we estimated the consistency and inter-rater agreement using random two-way intraclass correlations (McGraw & Wong, 1996; Shrout & Fleiss, 1979). Second, for each scorer, correlations were calculated between scores on the Bender-II and K-BIT, and finally these correlations were compared with a test for dependent correlations with a common element (Steiger, 1980, Williams, 1959). The results indicate that there were slight differences between two scorers, but one of them had comparatively lower coefficients of consistency and agreement. In the all scorers, the magnitude of the consistency coefficients (> .85) and agreement (> .84) between the qualifiers indicate good levels of concordance with even moderate exercise time (two or three sessions). Correlations between scores on the Bender-II and K-BIT were around .43 and .61, and the lowest correlations occurred in the scorer that showed less consistency and agreement with other scorers, clearly indicating the impact of measurement error in the validity correlations. Compared with one of the rating, this difference was statistically significant, and the percentage reduction of covariance was at least 5%. Finally, the results indicate several points. First, we present other evidence for inter-rater reliability of the Bender-II, and that there were good levels of agreement and consistency. Second, there is potentially a reduction in the correlations of validity when a scorer has trouble for interpret consistently and correctly Global Scoring System. Correlations decreased, however, are not equal in all the scorers, and therefore must be verified the goodness of fit between scorer and the Bender it's qualification method approach. The results can be are idiosyncratic to the sample and study conditions, and the sample size constraints threaten the generalizability of the findings. However, the study conditions are close to professional practice and therefore can be generalized to some extent. In addition, can serve as a baseline to compare future studies of reliability in the Bender-II.

RESUMO

Hace algunos años, se ha publicado el nuevo Test Gestáltico de Bender, segunda versión (Bender-II). Esta nueva versión usa el Sistema de Calificación Global (SCG) para obtener los puntajes, que enfatiza la reproducción exacta de los diseños; junto con otros cambios estructurales, consiste en la mayor modificación realizada al Test de Bender para evaluar la habilidad visomotora en varias etapas del desarrollo humano. Pero aún hay pocas investigaciones que han estudiado su funcionamiento psicométrico en muestras hispanas y especialmente el error de medición en el procedimiento de la calificación. Se investigó el efecto de la variabilidad de la calificación del nuevo Bender-II sobre su validez de constructo con una medida de inteligencia. Se administraron el Bender-II y el Test Breve de Inteligencia de Kaufman (K-BIT) a 60 niños preescolares, y tres calificadores calificaron las figuras reproducidas mediante procedimientos estandarizados y el SCG. El análisis comparó las correlaciones obtenidas por cada calificador entre los puntajes del Bender-II y del K-BIT. Se halló que la variabilidad de los puntajes proveniente de la interpretación del SCG afectó moderadamente las correlaciones con el puntaje total y de las subescalas del K-BIT. Un calificador fue menos confiable y sus puntajes mostraron al menos 5% menos variancia compartida al compararlo con los otros calificadores. Se concluye que la interpretación de la validez se puede distorsionar aun cuando el error de medición es moderado pues interaccionan con otras fuentes de error. Esto sugiere que se debe garantizar un buen acuerdo en la calificación de pruebas que requieran juicio.(AU)

Although the impact of the measurement error in the accuracy of the classification of subjects and validity correlations is theoretically established, in a practical situation has not been explored the degree of impact on the new Bender-II (Brannigan & Decker, 2003). The practical situation of assessment is that which occurs in the professional context, in which one or more examiners of an assessment team assessing children in a particular institution. The new Bender-II has substantial modifications in its structure and functioning, making it different from the original instrument proposed by Bender (1938, 1946). Structural changes consisted in more of items (16 designs), complementary tests (fine motor and visual perception) and two major tests (Visual Constructive Memory and Visual Motor), the rating method Global Scoring System (GSS) and standardized record sheet for the childs behavior during the test administration. The GSS was created ad hoc for the Bender-II, and it is a method that emphasizes the exact reproduction of the designs; its origin is in the original gestalt approach of Bender. Main studies have been published in the manual (Brannigan & Decker, 2003), and subsequent studies have used the American standardization sample. However, in non-immigrant Hispanic population, to date there are some unpublished and published only one (Merino, 2012); therefore, it is not known how generalizable the findings and psychometric properties obtained in the American standardization sample are. The aim of the study was to examine the effect of the variability of the scoring of designs of the new Bender-II on construct validity with a measure of intelligence. The Bender-II and Kaufman Brief Intelligence Test (K-BIT - Kaufman, A. S. & Kaufman, A. L., 1994) was administered to 60 preschool children (between 4 and 5 years, 33 girls), and three scorers rated the designs reproduced, by standardized procedures and GSS. The analysis consisted of two steps: first, we estimated the consistency and inter-rater agreement using random two-way intraclass correlations (McGraw & Wong, 1996; Shrout & Fleiss, 1979). Second, for each scorer, correlations were calculated between scores on the Bender-II and K-BIT, and finally these correlations were compared with a test for dependent correlations with a common element (Steiger, 1980, Williams, 1959). The results indicate that there were slight differences between two scorers, but one of them had comparatively lower coefficients of consistency and agreement. In the all scorers, the magnitude of the consistency coefficients (> .85) and agreement (> .84) between the qualifiers indicate good levels of concordance with even moderate exercise time (two or three sessions). Correlations between scores on the Bender-II and K-BIT were around .43 and .61, and the lowest correlations occurred in the scorer that showed less consistency and agreement with other scorers, clearly indicating the impact of measurement error in the validity correlations. Compared with one of the rating, this difference was statistically significant, and the percentage reduction of covariance was at least 5%. Finally, the results indicate several points. First, we present other evidence for inter-rater reliability of the Bender-II, and that there were good levels of agreement and consistency. Second, there is potentially a reduction in the correlations of validity when a scorer has trouble for interpret consistently and correctly Global Scoring System. Correlations decreased, however, are not equal in all the scorers, and therefore must be verified the goodness of fit between scorer and the Bender its qualification method approach. The results can be are idiosyncratic to the sample and study conditions, and the sample size constraints threaten the generalizability of the findings. However, the study conditions are close to professional practice and therefore can be generalized to some extent. In addition, can serve as a baseline to compare future studies of reliability in the Bender-II.(AU)

RESUMO

Objetivou-se com este estudo avaliar os parâmetros comportamentais e as estratégias de deslocamento e alimentação de vacas de descarte em pastagens de milheto ou capim sudão. Os tratamentos consistiram em: pastagem de milheto (Pennisetum americanum (L.) Leeke) ou pastagem de capim sudão (Sorghum bicolor cv. sudanense), ambos tratamentos submetidos ao pastejo contínuo de vacas de descarte, ao longo de 63 dias experimentais, subdividido em três períodos. Foram utilizadas 20 vacas de descarte cruza Charolês x Nelore, de idade média de 8 anos e peso vivo médio inicial de 445 kg. Os animais foram distribuídos em 10 piquetes, sendo utilizados cinco piquetes para cada tratamento comportando duas vacas. As avaliações comportamentais foram realizadas durante 24 horas ininterruptas. O delineamento experimental foi inteiramente casualizado com 2 tratamentos e 3 períodos de avaliação. O tempo de pastejo das vacas apresentou interação (P=0,0035) entre tratamento e período, sendo o menor tempo destinado à atividade no primeiro período na pastagem de milheto (504 minutos) comparado com o segundo período desse mesmo tratamento (587 minutos) e terceiro período nas pastagens de capim sudão (535 minutos). Os tempos de ruminação e ócio foram semelhantes entre os tratamentos; no entanto, o de ócio diminuiu e o de ruminação aumentou com o avanço dos períodos. As espécies de forrageiras não influenciaram as variáveis relacionadas às estratégias de deslocamento e alimentação. Com o avanço do ciclo das pastagens, o número de passos por minuto, estações por minuto e por dia diminuíram enquanto a taxa de bocado e número de bocados por dia aumentaram. Os parâmetros comportamentais de vacas de descarte em pastagens de milheto ou capim sudão são similares; no entanto, o avanço do ciclo vegetativo dessas espécies proporciona modificações no padrão comportamental dos animais.

The objective of this study was to evaluate the behavioral parameters and strategies of displacement and feeding of cull cows grazing millet or sudan grass. The treatments consisted of: pearl millet (Pennisetum americanum (L.) Leeke) or sudan grass (Sorghum bicolor cv. Sudanense). Both treatments were submitted to continuous grazing of cull cows over 63 experimental days subdivided into three periods. Using 20 Charolais x Nellore cull cows, at the average age of 8 years and average weight of 445 kg. The animals were divided into 10 paddocks, five paddocks used for each treatment comprising two cows. The behavioral assessments were carried out for 24 hours straight. The experimental design was completely randomized with two treatments and three periods. The grazing time of cows showed interaction (P = 0.0035) between treatment and period, and the shortest time for the activity in the first period on pearl millet (504 minutes) compared to the second period of that same treatment (587 minutes) and the third period on sudan grass pastures (535 minutes). The times of rumination and idling were similar between treatments; however, the idling time decreased and rumination increased with time periods. The forage species did not affect the variables related to the strategies of displacement and feeding. With the advancement of cycle pastures the number of steps per minute, stations per minute and per day decreased while the bite rate and the number of bites per day increased. The behavioral parameters of cull cows grazing sudan grass or millet are similar; however, the advancement of the vegetative cycle of these species provides changes in the behavioral pattern of the animals.

Assuntos

RESUMO

Objetivou-se com este estudo avaliar os parâmetros comportamentais e as estratégias de deslocamento e alimentação de vacas de descarte em pastagens de milheto ou capim sudão. Os tratamentos consistiram em: pastagem de milheto (Pennisetum americanum (L.) Leeke) ou pastagem de capim sudão (Sorghum bicolor cv. sudanense), ambos tratamentos submetidos ao pastejo contínuo de vacas de descarte, ao longo de 63 dias experimentais, subdividido em três períodos. Foram utilizadas 20 vacas de descarte cruza Charolês x Nelore, de idade média de 8 anos e peso vivo médio inicial de 445 kg. Os animais foram distribuídos em 10 piquetes, sendo utilizados cinco piquetes para cada tratamento comportando duas vacas. As avaliações comportamentais foram realizadas durante 24 horas ininterruptas. O delineamento experimental foi inteiramente casualizado com 2 tratamentos e 3 períodos de avaliação. O tempo de pastejo das vacas apresentou interação (P=0,0035) entre tratamento e período, sendo o menor tempo destinado à atividade no primeiro período na pastagem de milheto (504 minutos) comparado com o segundo período desse mesmo tratamento (587 minutos) e terceiro período nas pastagens de capim sudão (535 minutos). Os tempos de ruminação e ócio foram semelhantes entre os tratamentos; no entanto, o de ócio diminuiu e o de ruminação aumentou com o avanço dos períodos. As espécies de forrageiras não influenciaram as variáveis relacionadas às estratégias de deslocamento e alimentação. Com o avanço do ciclo das pastagens, o número de passos por minuto, estações por minuto e por dia diminuíram enquanto a taxa de bocado e número de bocados por dia aumentaram. Os parâmetros comportamentais de vacas de descarte em pastagens de milheto ou capim sudão são similares; no entanto, o avanço do ciclo vegetativo dessas espécies proporciona modificações no padrão comportamental dos animais.(AU)

The objective of this study was to evaluate the behavioral parameters and strategies of displacement and feeding of cull cows grazing millet or sudan grass. The treatments consisted of: pearl millet (Pennisetum americanum (L.) Leeke) or sudan grass (Sorghum bicolor cv. Sudanense). Both treatments were submitted to continuous grazing of cull cows over 63 experimental days subdivided into three periods. Using 20 Charolais x Nellore cull cows, at the average age of 8 years and average weight of 445 kg. The animals were divided into 10 paddocks, five paddocks used for each treatment comprising two cows. The behavioral assessments were carried out for 24 hours straight. The experimental design was completely randomized with two treatments and three periods. The grazing time of cows showed interaction (P = 0.0035) between treatment and period, and the shortest time for the activity in the first period on pearl millet (504 minutes) compared to the second period of that same treatment (587 minutes) and the third period on sudan grass pastures (535 minutes). The times of rumination and idling were similar between treatments; however, the idling time decreased and rumination increased with time periods. The forage species did not affect the variables related to the strategies of displacement and feeding. With the advancement of cycle pastures the number of steps per minute, stations per minute and per day decreased while the bite rate and the number of bites per day increased. The behavioral parameters of cull cows grazing sudan grass or millet are similar; however, the advancement of the vegetative cycle of these species provides changes in the behavioral pattern of the animals.(AU)

Assuntos