Propagation in a Decoupled Twin-Core Waveguide: A Frequency-Domain Analysis

The behavior of two waveguides, which are decoupled at a single frequency when a broadband pulse is launched into one of them, was studied recently in the time domain. We reinvestigate it in the frequency domain. This contributes to the clarification of the scope of the validity of previous results and allows extending them to dispersive waveguides. New results include a power spectral density conservation law and a revised calculation of the pulse breakup distance

Organogênese indireta a partir de explantes foliares e multiplicação in vitro de brotações de Eucalyptus benthamii X Eucalyptus dunnii.

Os objetivos deste trabalho foram avaliar diferentes meios de cultura na organogênese indireta e na multiplicação in vitro de brotos de Eucalyptus benthamii x Eucalyptus dunnii. Para organogênese, explantes foliares foram excisados no sentido transversal e cultivados in vitro, sendo os seguintes fatores testados: dois meios de cultura (MS N/2 e JADS) adicionados de 0,1 ?M de ANA, duas concentrações de thidiazuron (0,1 e 0,5 ?M) e presença ou não de PVP-40 (250 mg L-1). Após 70 dias de cultivo foram avaliadas as porcentagens de explantes oxidados totalmente, formando calo, produzindo antocianina, formando gema, formando brotações e o número de brotações formadas por explante regenerando. No experimento de multiplicação, brotações isoladas foram cultivadas em meio MS, JADS e WPM, adicionados de 1,11 ?M de BAP. Foram realizados quatro subcultivos a cada 28 dias e em cada subcultivo foram avaliados: a porcentagem de oxidação, de explantes apresentando clorose total ou parcial, massa fresca e número médio de brotos por explante. O meio de cultura MS N/2 suplementado com 0,1 ?M de ANA, 0,5 ?M de TDZ e PVP-40 promoveu a maior taxa de organogênese (8,3%). No meio de cultura MS com 1,11 ?M de BAP, a taxa de multiplicação foi maior que nos outros meios, no primeiro e segundo subcultivos (9,28 e 9,24 por mês), não havendo diferença entre os três meios nos demais subcultivos

Patterns and drivers of evapotranspiration in South American wetlands

Evapotranspiration (ET) is a key process linking surface and atmospheric energy budgets, yet its drivers and patterns across wetlandscapes are poorly understood worldwide. Here we assess the ET dynamics in 12 wetland complexes across South America, revealing major differences under temperate, tropical, and equatorial climates. While net radiation is a dominant driver of ET seasonality in most environments, flooding also contributes strongly to ET in tropical and equatorial wetlands, especially in meeting the evaporative demand. Moreover, significant water losses through wetlands and ET differences between wetlands and uplands occur in temperate, more water-limited environments and in highly flooded areas such as the Pantanal, where slow river flood propagation drives the ET dynamics. Finally, floodplain forests produce the greatest ET in all environments except the Amazon River floodplains, where upland forests sustain high rates year round. Our findings highlight the unique hydrological functioning and ecosystem services provided by wetlands on a continental scale

Avaliação pré-operatória dos testes cutâneos de hipersensibilidade retardada e da linfocitometria em pacientes com carcinoma epidermóide de esôfago

OBJECTIVE: Cutaneous tests for delayed hipersensivity have been used for differentiating preoperative immunologic status so as to determine nutritional performance. The aim of this study was to evaluate the immunologic status of patients with squamous cell carcinoma of the esophagus.PATIENTS AND METHODS: Delayed hipersensivity and lymphocytometry were preoperatively assessed in 45 patients with squamous cell carcinoma (cases) and90 patients with common surgical diseases (controls).RESULTS: Comparison of weight loss between the two groups showed that the case group was significantly more malnourished than the controls (P = 0.001). None of the cutaneous tests used (candidin, varidase, tricofitin, and tuberculin) showed statistical significance (P = NS) when the two groups were compared. There was statistical difference (P = 0.002) in lymphocytometry with a significant decrease of lymphocyte counts in the control group.CONCLUSIONS: The authors conclude that the cutaneous tests for delayed hipersensitivity were of little application for differentiating preoperative immunologicstatus to determine nutritional performance, while lymphocytometry seems to be a reliable test to evaluate cellular immunity in patients with squamous cell carcinoma. Lymphocytometry may be used as an additional test to assess malnutrition in these patients.OBJETIVO: Os testes cutâneos de hipersensibilidade retardada e a linfocitometria têm sido usados para determinação do estado imunológico de pacientes com câncer, relacionando suas alterações à piora do estado nutricional. O objetivo desse estudo foi avaliar o estado imunológico dos pacientes com carcinoma epidermóide de esôfago, determinando-se um perfil imunológico. PACIENTES E MÉTODOS: Foram estudados 45 pacientes com carcinoma epidermóide de esôfago (casos) e 90 pacientes com outras doenças cirúrgicas(controles) através dos testes cutâneos de hipersensibilidade retardada e da linfocitometria.RESULTADOS: A comparação entre os grupos em relação à perda de peso demonstrou que o grupo dos casos era estatisticamente mais desnutrido que oscontroles (P = 0.001). Nenhum dos testes cutâneos de hipersensibilidade retardada utilizados (candidina, varidase, tricofitina e tuberculina) apresentou diferençaestatisticamente significativa (P = NS) quando se compararam os dois grupos. Houve diferença estatística (P = 0.002) em relação à linfocitometria, com diminuiçãosignificativa da contagem de linfócitos nos pacientes com carcinoma epidermóide de esôfago.CONCLUSÕES: Os autores concluem que os testes cutâneos de hipersensibilidade retardada foram de pouca utilidade para diferenciar o estado imunológico préoperatório em ambos grupos estudados. Por outro lado, a linfocitometria demonstrou ser um bom método de avaliação da imunidade celular em pacientes com carcinoma epidermóide de esôfago, podendo ser utilizado como mais um teste para caracterizar desnutrição nesse grupo de pacientes

HNF4alpha Dysfunction as a Molecular Rational for Cyclosporine Induced Hypertension

Induction of tolerance against grafted organs is achieved by the immunosuppressive agent cyclosporine, a prominent member of the calcineurin inhibitors. Unfortunately, its lifetime use is associated with hypertension and nephrotoxicity. Several mechanism for cyclosporine induced hypertension have been proposed, i.e. activation of the sympathetic nervous system, endothelin-mediated systemic vasoconstriction, impaired vasodilatation secondary to reduction in prostaglandin and nitric oxide, altered cytosolic calcium translocation, and activation of the renin-angiotensin system (RAS). In this regard the molecular basis for undue RAS activation and an increased signaling of the vasoactive oligopeptide angiotensin II (AngII) remain elusive. Notably, angiotensinogen (AGT) is the precursor of AngII and transcriptional regulation of AGT is controlled by the hepatic nuclear factor HNF4alpha. To better understand the molecular events associated with cyclosporine induced hypertension, we investigated the effect of cyclosporine on HNF4alpha expression and activity and searched for novel HNF4alpha target genes among members of the RAS cascade. Using bioinformatic algorithm and EMSA bandshift assays we identified angiotensin II receptor type 1 (AGTR1), angiotensin I converting enzyme (ACE), and angiotensin I converting enzyme 2 (ACE2) as genes targeted by HNF4alpha. Notably, cyclosporine represses HNF4alpha gene and protein expression and its DNA-binding activity at consensus sequences to AGT, AGTR1, ACE, and ACE2. Consequently, the gene expression of AGT, AGTR1, and ACE2 was significantly reduced as evidenced by quantitative real-time RT-PCR. While RAS is composed of a sophisticated interplay between multiple factors we propose a decrease of ACE2 to enforce AngII signaling via AGTR1 to ultimately result in vasoconstriction and hypertension. Taken collectively we demonstrate cyclosporine to repress HNF4alpha activity through calcineurin inhibitor mediated inhibition of nuclear factor of activation of T-cells (NFAT) which in turn represses HNF4alpha that leads to a disturbed balance of RAS