Desempenho de cultivares de arroz de terras altas sob plantio direto e convencional.

Para avaliar a viabilidade de uso do plantio direto em arroz (Oryza sativa L.) de terras altas, bem como o comportamento das novas cultivares nesse sistema de cultivo, experimentos foram conduzidos em Santa Helena de Goiás (GO), Brasil, em um Latossolo Vermelho-Escuro, de uso contínuo sob plantio direto há 14 anos. Foram testadas 14 cultivares de arroz de terras altas sob plantio direto e convencional em duas safras (1998/99 e 1999/2000), utilizando delineamento de blocos casualizados, com quatro repetições. As parcelas constituíram-se de quatro linhas de 5 m, espaçadas de 0,4 m entre si. As variáveis avaliadas foram: produtividade de grãos, altura de plantas, florescimento, acamamento e incidência de doenças. Pelos resultados obtidos, verificaram-se altas produtividades de grãos das cultivares, as quais apresentam diferenças no desempenho em diferentes anos, porém semelhantes nos sistemas de plantio. Em condições de menor disponibilidade hídrica e na ausência de adubação na semeadura, o plantio direto proporciona rendimento de grãos igual ao plantio convencional

The gut microbiota, bile acids and their correlation in primary sclerosing cholangitis associated with inflammatory bowel disease.

BACKGROUND: Patients with primary sclerosing cholangitis associated with inflammatory bowel disease (PSC-IBD) have a very high risk of developing colorectal neoplasia. Alterations in the gut microbiota and/or gut bile acids could account for the increase in this risk. However, no studies have yet investigated the net result of cholestasis and a potentially altered bile acid pool interacting with a dysbiotic gut flora in the inflamed colon of PSC-IBD. AIM: The aim of this study was to compare the gut microbiota and stool bile acid profiles, as well as and their correlation in patients with PSC-IBD and inflammatory bowel disease alone. METHODS: Thirty patients with extensive colitis (15 with concomitant primary sclerosing cholangitis) were prospectively recruited and fresh stool samples were collected. The microbiota composition in stool was profiled using bacterial 16S rRNA sequencing. Stool bile acids were assessed by high-performance liquid chromatography tandem mass spectrometry. RESULTS: The total stool bile acid pool was significantly reduced in PSC-IBD. Although no major differences were observed in the individual bile acid species in stool, their overall combination allowed a good separation between PSC-IBD and inflammatory bowel disease. Compared with inflammatory bowel disease alone, PSC-IBD patients demonstrated a different gut microbiota composition with enrichment in Ruminococcus and Fusobacterium genus compared with inflammatory bowel disease. At the operational taxonomic unit level major shifts were observed within the Firmicutes (73%) and Bacteroidetes phyla (17%). Specific microbiota-bile acid correlations were observed in PSC-IBD, where 12% of the operational taxonomic units strongly correlated with stool bile acids, compared with only 0.4% in non-PSC-IBD. CONCLUSIONS: Patients with PSC-IBD had distinct microbiota and microbiota-stool bile acid correlations as compared with inflammatory bowel disease. Whether these changes are associated with, or may predispose to, an increased risk of colorectal neoplasia needs to be further clarified.info:eu-repo/semantics/publishedVersio

Differential mesenteric fat deposition in bovines fed on silage or concentrate is independent of glycerol membrane permeability

© The Animal Consortium 2011In the meat industry, the manipulation of fat deposition in cattle is of pivotal importance to improve production efficiency, carcass composition and ultimately meat quality. There is an increasing interest in the identification of key factors and molecular mechanisms responsible for the development of specific fat depots. This study aimed at elucidating the influence of breed and diet on adipose tissue membrane permeability and fluidity and their interplay on fat deposition in bovines. Two Portuguese autochthonous breeds, Alentejana and Barrosã, recognized as late- and early-maturing breeds, respectively, were chosen to examine the effects of breed and diet on fat deposition and on adipose membrane composition and permeability. Twenty-four male bovines from these breeds were fed on silage-based or concentrate-based diets for 11 months. Animals were slaughtered to determine their live slaughter and hot carcass weights, as well as weights of subcutaneous and visceral adipose depots. Mesenteric fat depots were excised and used to isolate adipocyte membrane vesicles where cholesterol content, fatty acid profile as well as permeability and fluidity were determined. Total accumulation of neither subcutaneous nor visceral fat was influenced by breed. In contrast, mesenteric and omental fat depots weights were higher in concentrate-fed bulls relative to silage-fed animals. Membrane fluidity and permeability to water and glycerol in mesenteric adipose tissue were found to be independent of breed and diet. Moreover, the deposition of cholesterol and unsaturated fatty acids, which may influence membrane properties, were unchanged among experimental groups. Adipose membrane lipids from the mesenteric fat depot of ruminants were rich in saturated fatty acids, and unaffected by polyunsaturated fatty acids dietary levels. Our results provide evidence against the involvement of cellular membrane permeability to glycerol on fat accumulation in mesenteric fat tissue of concentrate-fed bovines, which is consistent with the unchanged membrane lipid profile found among experimental groups.This study was supported by Fundação para a Ciência e a Tecnologia (FCT) through grant PTDC/CVT/2006/66114 and individual fellowships to Ana P. Martins (SFRH/BD/2009/65046), Ana S. H. Costa (SFRH/BD/2009/61068) and Susana V. Martins (SFRH/BPD/2009/63019). Paula A. Lopes is a researcher from the program ‘‘Ciência 2008’’ from FC

Critical wave-packet dynamics in the power-law bond disordered Anderson Model

We investigate the wave-packet dynamics of the power-law bond disordered one-dimensional Anderson model with hopping amplitudes decreasing as $H_{nm}\propto |n-m|^{-\alpha}$. We consider the critical case ($\alpha=1$). Using an exact diagonalization scheme on finite chains, we compute the participation moments of all stationary energy eigenstates as well as the spreading of an initially localized wave-packet. The eigenstates multifractality is characterized by the set of fractal dimensions of the participation moments. The wave-packet shows a diffusive-like spread developing a power-law tail and achieves a stationary non-uniform profile after reflecting at the chain boundaries. As a consequence, the time-dependent participation moments exhibit two distinct scaling regimes. We formulate a finite-size scaling hypothesis for the participation moments relating their scaling exponents to the ones governing the return probability and wave-function power-law decays

Influência da artrite encefalite caprina na resposta superovulatória.

Resumo: Objetivando avaliar a resposta superovulatoria e a qualidade embrionaria pos-colheita em animais soropositivos para o virus da CAEV, foram utilizadas 18 cabras adultas da raca Saanen, sendo 12 soropositivas(G1) e seis soronegativas(G2). Nao se observou diferencas significativas(P>0,05) entre o G1 e G2 quanto a resposta do estro, 100,0% vs. 83,0%; ao inicio do estro(hora) em relacao ao momento da retirada das esponjas, 35,0+/-9,5 vs. 31,2+/-10,7; a duracao do estro(hora), 27,0+/-5,4 vs. 28,8+/-10,7; a taxa de ovulacao, 10,8+/-5,7 vs. 10,8+/-8,6; e a porcentagem de estruturas recuperadas, 72,0 vs. 67,0 e de embrioes viaveis 99,0 vs. 99,0 vs. 95,0, respectivamente. Considerando que a transferencia de embrioes e uma tecnica segura para o controle da CAEV e diante da resposta satisfatoria dos animais soropositivos, em especial, quanto as porcentagens de embrioes recuperados e viaveis, conclui-se que animais geneticamente superiores mesmo que soropositivos para a CAEV podem ser usados como doadores de embrioes. [The influence of caprine arthritis encephalitis on superovulatory response]. Abstract: The objectives of this work were to determine the ovulation rate and the embryo viability in seropositive animals to Caprine Arthritis Encephalitis Virus infection (CAEV). Eighteen goats of the Saanen breed were used, 12 CAEV-seropositives (G1) and six CAEV-seronegatives (G2). No statistical difference (P>0.05) was observed between groups (G1 and G2) in relation to estrus response, 100.0% vs. 83.0%; onset estrus (hours), 35.0+9,5 vs. 31.2+10.7; estrus duration (hours), 27.0+5.4 vs. 28.8+10.7; ovulation rate, 10.8+5.7 vs. 10.8+8.6; recovery rate of embryos, 72.0% vs. 67.0%; and viable embryos, 99.0% vs. 95.0%, respectively. Considering the embryo transfer is a safe technique for the control of CAEV and due to the fact that the seropositive female show a satisfatory response for embryo recovery rate and viability, we conclude that the CAEV-seropositive animals may be used as embryo donors

Influência da artrite encefalite caprina na resposta superovulatória.

Resumo: Objetivando avaliar a resposta superovulatória e a qualidade embrionária pós-colheita em animais soropositivos para o vírus da Artrite Encefalite Caprina (CAEV), foram utilizadas 18 cabras adultas da raça Saanen, sendo 12 soropositivas (G1) e seis soronegativas (G2).Não se observou diferenças significativas (P>0,05) entre o G1 e G2 quanto à resposta do estro, 100,0% vs. 83,0%; ao início do estro (hora) em relação ao momento da retirada das esponjas, 35,0±9,5 vs. 31,2±10,7; à duração do estro (hora), 27,0± 5,4 vs. 28,8±10,7; à taxa de ovulação, 10,8±5,7 vs. 10,8±8,6; e à porcentagem de estruturas recuperadas, 72,0 vs. 67,0 e de embriões viáveis 99,0 vs. 95,0, respectivamente. Considerando que a transferência de embriões é uma técnica segura para o controle da CAEV e diante da resposta satisfatória dos animais soropositivos, em especial, quanto as porcentagens de embriões recuperados e viáveis, concluí-se que animais geneticamente superiores mesmo que soropositivos para a CAEV podem ser usados como doadores de embriões. [The influence of caprine arthritis encephalitis on superovulatory response]. Abstract: The objectives of this work were to determine the ovulation rate and the embryo viability in seropositive animals to Caprine Arthritis Encephalitis Virus infection (CAEV). Eighteen goats of the Saanen breed were used, 12 CAEV-seropositives (G1) and six CAEV-seronegatives (G2). No statistical difference (P>0.05) was observed between groups (G1 and G2) in relation to estrus response, 100.0% vs. 83.0%; onset estrus (hours), 35.0+9,5 vs. 31.2+10.7; estrus duration (hours), 27.0+5.4 vs. 28.8+10.7; ovulation rate, 10.8+5.7 vs. 10.8+8.6; recovery rate of embryos, 72.0% vs. 67.0%; and viable embryos, 99.0% vs. 95.0%, respectively. Considering the embryo transfer is a safe technique for the control of CAEV and due to the fact that the seropositive female show a satisfatory response for embryo recovery rate and viability, we conclude that the CAEV-seropositive animals may be used as embryo donor

Unitary transformation approach for the trapped ion dynamics

We present a way of treating the problem of the interaction of a single trapped ion with laser beams based on successive aplications of unitary transformations onto the Hamiltonian. This allows the diagonalization of the Hamiltonian, by means of recursive relations, without performing the Lamb-Dicke approximation.Comment: 8 page

Diferentes posologias de flunixin meglumine na prevenção da regressão prematura de corpos lúteos em cabras superovuladas.

Resumo: O presente trabalho objetivou testar a eficiência na redução da freqüência de aplicações do flunixin meglumine a partir de duas dosagens, em relação à taxa de corpos lúteos regredidos prematuramente. Utilizou-se 18 fêmeas de raças caprinas leiteiras, Saanen e Anglo-nubiana, as quais foram submetidas à sincronização do estro com esponjas intravaginais e cloprostenol, e à superovulação com FSH suíno. Três dias após a retirada das esponjas os animais foram submetidos a três tratamentos (T1; T2 e T3) com as seguintes dosagens de flunixin meglumine por kg de peso corpóreo (PC) e por aplicação: 1,1mg; 1,1mg e 2,2 mg, respectivamente, sendo realizadas em T1 oito aplicações intervaladas por 12 horas e em T2 e T3 quatro aplicações intervaladas por 24 h. Observou-se diferença significativa (P<0,05) na percentagem de corpos lúteos regredidos para os tratamentos com uma única aplicação diária (T2 - 14,29 e T3 - 22,58) em relação ao tratameto com duas aplicações diárias (T1- 0,00), o que leva a supor que a duração do efeito do flunixin meglumine, em cabras, seja inferior a 24 horas, tornando o regime de aplicação, com esse intervalo de frequência, ineficiente em inibir totalmente a regressão prematura de corpos lúteos. No entando, a média de embriões colhidos e a viabilidade deles não variaram entre os tratamentos. Em adição, a percentagem de estruturas colhidas foi superior no tratamento que utilizou 1,1 mg.kg-1 por PC em uma aplicação (T1 - 80,36) em relação a duas aplicações diárias (T1 - 54,88). Desta forma, buscando-se a praticidade e a redução na concentração da droga utilizada por cabra, pode-se indicar para o tratamento anti-luteolítico a dosagem de 1,1 mg.kg-1 por PC, administrada uma vez ao dia. [Different flunixin meglumine administrations to control of the corpus luteum premature regression in superovulated goats]. Abstract: The present study has tested the efficiency of the reduction of frequency of applications of flunixin meglumine from a two doses use, in relation to the rate of premature corpus luteum regression. the oestrus cycles of 18 does of Saanen and Nubian breeds were synchronized with intravaginal pessaries and cloprostenol, and superovulated with porcine FSH. Three days after withdrawal of sponges three treatments were begun (T1;T2 e T3) with 1.1mg, 1.1mg and 2.2 mg.kg-1 of flunixin meglumine administered, respectively. The does of T1 received eight applications, with 12 h of interval and T2 e T3, four applications with an interval of 24 hours. Significant difference (P<0.05) was observed on the percentage of regressed corpus lutea between the treatment that used only one application daily (T2 - 14.29 and T3 - 22.58), and that which used twice aplications daily (T1 - 0.00). This finding suggests that the duration of the flunixin effect in goats is shorter than 24 hours, making the application regime with this interval of frequency inefficient to completely inhibit the premature regression of the corpus luteum. However, the rate of recovered and embryos viability did not change between treatments. In addition, the percentage of recovered structures was higher in the treatment that used 1.1 mg.kg-1 on one administration daily (T2 - 80.36) than that used two daily administration (T1 - 54.88). Thus our study suggests that in espect of convenient treatment and reduction of the dose used in goats, the dosage of 1.1 mg.kg-1 once daily is indicated

Delocalization in harmonic chains with long-range correlated random masses

We study the nature of collective excitations in harmonic chains with masses exhibiting long-range correlated disorder with power spectrum proportional to $1/k^{\alpha}$, where $k$ is the wave-vector of the modulations on the random masses landscape. Using a transfer matrix method and exact diagonalization, we compute the localization length and participation ratio of eigenmodes within the band of allowed energies. We find extended vibrational modes in the low-energy region for $\alpha > 1$. In order to study the time evolution of an initially localized energy input, we calculate the second moment $M_2(t)$ of the energy spatial distribution. We show that $M_2(t)$, besides being dependent of the specific initial excitation and exhibiting an anomalous diffusion for weakly correlated disorder, assumes a ballistic spread in the regime $\alpha>1$ due to the presence of extended vibrational modes.Comment: 6 pages, 9 figure