On the structural, electronic, and optical properties of L-histidine crystal: a DFT study.

CONTEXT: The monoclinic L-histidine crystal is critical for protein structure and function and is also found in the myelin of brain nerve cells. This study numerically examines its structural, electronic, and optical properties. Our findings indicate that the L-histidine crystal has an insulating band gap of approximately 4.38 eV. Additionally, electron and hole effective masses range between 3.92[Formula: see text]-15.33[Formula: see text] and 4.16[Formula: see text]-7.53[Formula: see text], respectively. Furthermore, our investigation suggests that the L-histidine crystal is an excellent UV collector due to its strong optical absorption activity for photon energies exceeding 3.5 eV. METHODS: To investigate the structural, electronic, and optical properties of L-histidine crystals, we used the Biovia Materials Studio software to conduct Density Functional Theory (DFT) simulations as implemented in the CASTEP code. Our DFT calculations were performed using the generalized gradient approximation (GGA) as parameterized by the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional, with an additional dispersion energy correction (PBE [Formula: see text] TS) based on the model proposed by Tkatchenko and Scheffler to describe van der Waals interactions. Additionally, we employed the norm-conserving pseudopotential to treat core electrons.

Glyphosate adsorption on C60 fullerene in aqueous medium for water reservoir depollution.

The indiscriminate use of pesticides has caused several damages to the environment, in particular the pollution of water reservoirs, so that this has motivated the development of techniques to minimize its consequences. One of the main surface water pollutants is glyphosate, which is a widely used herbicide for weed control. Therefore, in this work, computational simulations were used with density functional theory and molecular dynamics to theoretically verify if C60 fullerene is capable of adsorbing glyphosate in aqueous media. As a result, we showed through the adsorption energies, molecular dynamics methods, and infrared absorption that C60 can adsorb glyphosate molecules in at least three distinct configurations, either in vacuum or in water, which theoretically indicates it as a good candidate for removal of this herbicide from water by nanotechnology techniques.

Analysis of bovine rotavirus strains circulating in diarrheic dairy calves in Uberaba, Minas Gerais, Brazil, during 2008-2009 / Análise de cepas de rotavírus bovino circulantes em bezerros leiteiros com diarreia em Uberaba, Minas Gerais, Brasil, durante 2008-2009

O objetivo deste estudo foi detectar rotavírus em fezes de bezerros com diarreia em Uberaba, MG, e caracterizar os genes VP7 e VP4 por meio da genotipagem e da análise filogenética. Setenta e quatro amostras foram coletadas entre novembro de 2008 e setembro de 2009. A detecção do vírus foi feita por teste de aglutinação e as amostras positivas foram submetidas à transcrição reversa, seguida de reação em cadeia da polimerase (RT-PCR), tipagem por PCR e sequenciamento. A taxa de detecção de rotavírus foi de 6,8% e todas as amostras apresentaram o genótipo G6P[5]. A análise filogenética mostrou que as amostras do genótipo G6 pertencem à linhagem IV e que, para ambos os genes (VP7 e VP4), as amostras deste estudo compõem um sub-cluster à parte daquele das cepas referências e das amostras campo mais similares. O alinhamento das sequências de aminoácidos deduzidas mostrou substituições em regiões antigênicas quando comparadas com as sequências das cepas bovinas UK e NCDV, presentes nas vacinas disponíveis no Brasil. Uma nova sublinhagem genética de G6P[5] foi evidenciada neste estudo. Substituições de aminoácidos nas regiões antigênicas dos rotavírus e a circulação de novas variantes podem representar desafios para as vacinas utilizadas atualmente. O presente estudo contribui para a compreensão da epidemiologia dos rotavírus bovinos no Brasil.(AU)

Geostatistics as a tool to study mite dispersion in physic nut plantations.

Spatial distribution studies in pest management identify the locations where pest attacks on crops are most severe, enabling us to understand and predict the movement of such pests. Studies on the spatial distribution of two mite species, however, are rather scarce. The mites Polyphagotarsonemus latus and Tetranychus bastosi are the major pests affecting physic nut plantations (Jatropha curcas). Therefore, the objective of this study was to measure the spatial distributions of P. latus and T. bastosi in the physic nut plantations. Mite densities were monitored over 2 years in two different plantations. Sample locations were georeferenced. The experimental data were analyzed using geostatistical analyses. The total mite density was found to be higher when only one species was present (T. bastosi). When both the mite species were found in the same plantation, their peak densities occurred at different times. These mites, however, exhibited uniform spatial distribution when found at extreme densities (low or high). However, the mites showed an aggregated distribution in intermediate densities. Mite spatial distribution models were isotropic. Mite colonization commenced at the periphery of the areas under study, whereas the high-density patches extended until they reached 30 m in diameter. This has not been reported for J. curcas plants before.

Efficiency and economic feasibility of pest control systems in watermelon cropping.

The aim of this work was to determine the efficiency and feasibility of two different watermelon pest control systems on pest infestations, natural enemies, and on the productivity and sustainability of watermelon cropping. Two independent experiments were carried out during the dry season of 2011. Both experiments were carried out using a randomized block experimental design, with three treatments; weekly application of pesticide (WAP), integrated pest management (IPM), and nonpesticide application (control); and four replicates. Arthropods sampling was performed every 2 d by direct counting at five randomly selected points in each plot. Samples were taken by beating the leaves from the apical portion of the plant against a white plastic tray. Arthropods that moved along the soil surface were sampled weekly using pitfall traps. Both WAP and IPM treatments negatively affected the arthropod population. We conclude that IPM is an attractive strategy for watermelon cropping both economically and environmentally because it provides the grower with an option to lower production cost, achieves the same production, and there is less need for pesticide application when compared with the prophylactic control treatment when pesticides are applied on a weekly basis. This has not been reported for watermelon before.

A pratica da amamentacao no municipio de Paulinia, Estado de Sao Paulo, Brasil. / Breast feeding practice in the municipality of Paulinia, State of Sao Paulo, Brazil

Em 1977 foi realizado um inquerito no municipio de Paulinia, Estado de Sao Paulo (Brasil), com a finalidade de se estudar o aleitamento materno das criancas de ate 2 anos de idade. O inquerito forneceria dados a serem utilizados para avaliar um programa de estimulo ao aleitamento materno, a ser desenvolvido mais tarde. A idade media das criancas no desmame foi 3.3 meses, e 2.2 meses ao comecar a tomar leite em mamadeira. No final do primeiro mes, 74% das criancas estavam sendo amamentadas e 57% estavam com aleitamento exclusivo.As criancas de maes com 28 anos ou mais tiveram uma amamentacao exclusiva significativamente mais longa que as criancas de maes mais jovens. A residencia, urbano/rural, e o sexo das criancas nao influiram na duracao da amamentacao

[Post-anoxic myoclonic encephalopathy (Lance-Adams syndrome): report of 6 cases]. / Encefalopatia mioclônica pós-anóxica (síndrome de Lance-Adams): registro de seis casos]

Six patients are studied (five females and one male) in which disorders of consciousness varying from stupor to coma have occurred following variable periods of cerebral hypoxia caused either by cardiorespiratory standstill (five cases) or acute pulmonary injury. After a few hours they had generalized convulsive crisis of tonic-clonic type. As consciousness was regained they developed generalized myoclonic trembling of great intensity. Hence post-anoxic myoclonic encephalopathy is characterized. It is also called the Lance-Adams syndrome, in honor of the authors that described it in 1963. Five patients underwent electroencephalographic examination; the tracing showed typical myoclonus potentials in some, and characteristic diffuse brain injury in others. Electromyography was carried out in one patient, and cerebral computerized tomography in two others. The latter revealed an accentuated widening of sylvian cleft at the base in one them, specially on the right side, which explain his dementia-like picture. The biochemical analysis of the spinal fluid was normal in five cases.

Encefalopatia mioclonica pos-anoxica (sindrome de Lance-Adams): registro de seis casos. / Post-anoxic myoclonic encephalopathy (Lance-Adams syndrome): report of 6 cases

Sao estudados seis pacientes, cinco do sexo feminino e um dos masculino, os quais, apos terem sofrido periodos variaveis de hipoxia cerebral provocada ou por parada cardio-respiratoria (cinco casos) ou por comprometimento pulmonar agudo, apresentaram alteracoes dos niveis de conciencia, que variaram de obnubilacao ao coma. Horas apos, tiveram crises convulsivas generalizadas do tipo tonico clonica. A medida que vieram recuperando a consciencia, desenvolveram abalos mioclonicos generalizados, de grande intensidade. Assim ficou caracterizada a encefalopatia mioclonica pos-anoxica que em homenagem aos autores que a descreveram, em 1963 e denominada tambem de sindrome de Lance-Adams. Cinco enfermos foram submetidos a exame eletrencefalografico, cujos tracados, em alguns, mostraram potenciais tipicos de mioclonias e, em outros, caracteristicas de comprometimento cerebral difuso por anoxia. Em um dos pacientes foi feito exame eletromiografico e em outros dois, tomografia cerebral por computador que revelou, em um deles, pronunciado alargamento das cisuras silvianas na base, especialmente a direita que justifica o quadro demencial apresentado por tal paciente. A analise bioquimica do liquido cefalorraquidiano feito em cinco casos, nao apresentou alteracoes

[Teenage pregnancy. Pt. 1. Contraception and sexuality behavior (author's transl)]. / Gravidez na adolescencia. pt 1. conduta frente a anticoncepcao e ao sexo.

PIP: 122 adolescents of average age 16.3 who delivered their first baby at the Medical School of Campinas, Brazil, were surveyed through a questionnaire devised for the purpose, to investigate their contraceptive knowledge and sexual behavior. 64% of girls declared they wanted to become pregnant; 45.9% did not; 91% knew about contraceptive practices, especially the pill, but only 11.5% of them had used a method. The main reason not to use contraception was fear of side effects. After delivery 64% wanted to use contraception, and 23.7% did not. 57.7% of girls had had their first sexual relation at age 15 or earlier, and 29.5% had had their first period at age 13. About half stated to enjoy sexual relations, but most had diminished the frequency of sexual contacts during pregnancy for fear of hurting the fetus; some had stoppped enjoying sex during pregnancy. This study reveals that most adolescents needed to be educated about sex and related problems, especially contraception; specific plans should be studied and implemented to serve this particular category of patients.^ieng