Visualization of fetal tongue circulation using Doppler ultrasound

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154681/1/uog20393_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154681/2/uog20393.pd

Irrigation performance assessments for corn crop with LANDSAT images in the São Paulo State, Brazil.

A evapotranspiração (ET) e coeficiente de cultura (Kc) foram modelados em uma fazenda comercial com a cultura do milho irrigada por pivôs centrais para grãos e silagem, no lado noroeste do Estado de São Paulo, Brasil. Para obtenção da ET, o algoritmo SAFER (Simple Algorithm For Evapotranspiration Retrieving) foi aplicado em imagens do satélite Landsat durante os ciclos produtivos (CP) de março a agosto de 2010. Funções polinomiais relacionando o coeficiente de cultura (Kc) com os graus-dias acumulados (GDac) permitiram a estimativa da evapotranspiração em condições potenciais (ETp). Adicionando dados de evapotranspiração de referência (ET0), precipitação (P), irrigação (I) e produtividade (Yp), os desempenhos de irrigação foram analisados. A Evapotranspiração Relativa (RET) ficou entre 0,78 e 1,00 enquanto que a Deficiência Hídrica (WD) apresentou um máximo de 110 mm CP-1. O Suprimento de Água Relativo (RWS) com valores de 1,1 a 1,4 evidenciou altas taxas de drenagem. Os valores físicos da produtividade da água, baseada na ET (WPET) estiveram entre 1,4 e 2,8 kg m-3 para grãos e 8,8 e 14,1 kg m-3 para silagem, com os valores monetários correspondentes para grãos de 0,34 a 0,68 US$ m-3, apresentando elevado retorno quando comparados com outras culturas anuais.Esse artigo também foi publicado na revista Water Resources and Irrigation Management, v. 3, n. 2, 2014

Distribuição espacial do requerimento hídrico da cultura do milho no Estado de São Paulo.

Imagens do satélite Landsat e dados agrometeorológicos foram usadas em conjunto para a obtenção da evapotranspiração atual (ET) e modelagem do coeficiente de cultura (Kc) em pivôs de irrigação com mistura de híbridos de milho em uma fazenda comercial de grãos e silagem. Após análises dos histogramas de distribuição de frequência, os valores médios dos pixels da ET durante estágios da cultura ficaram entre 1,1 e 4,4 mm dia-1. Considerando-se ausência de estresse hídrico, relações entre Kc e os graus-dias acumulados (GDac) foram aplicadas no Estado de São Paulo no período de março a agosto para obtenção dos requerimentos hídricos (RH) com ênfase nas mesorregiões produtoras. Destaques são para Presidente Prudente, com valores de RH médios mais altos de 404 ± 13 mm e 353 ± 12 mm, para respectivamente produção de grãos e silagem. A mesorregião de Itapetininga apresentou os valores correspondentes mais baixos de 311 ± 16 mm e 257 ± 14 mm. Os resultados da presente pesquisa são úteis para o planejamento da melhoria da produtividade da água da cultura do milho de acordo com a finalidade comercial, tanto em condições de irrigação como na dependência de água da chuva

Prediction of adverse perinatal outcome by fetal biometry: comparison of customized and populationâ based standards

ObjectiveTo compare the predictive performance of estimated fetal weight (EFW) percentiles, according to eight growth standards, to detect fetuses at risk for adverse perinatal outcome.MethodsThis was a retrospective cohort study of 3437 Africanâ American women. Populationâ based (Hadlock, INTERGROWTHâ 21st, World Health Organization (WHO), Fetal Medicine Foundation (FMF)), ethnicityâ specific (Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)), customized (Gestationâ Related Optimal Weight (GROW)) and Africanâ American customized (Perinatology Research Branch (PRB)/NICHD) growth standards were used to calculate EFW percentiles from the last available scan prior to delivery. Prediction performance indices and relative risk (RR) were calculated for EFW â 90th percentiles, according to each standard, for individual and composite adverse perinatal outcomes. Sensitivity at a fixed (10%) falseâ positive rate (FPR) and partial (FPR â 90th percentile were also at risk for any adverse perinatal outcome according to the INTERGROWTHâ 21st (RRâ =â 1.4; 95%â CI, 1.0â 1.9) and Hadlock (RRâ =â 1.7; 95%â CI, 1.1â 2.6) standards, many times fewer cases (2â 5â fold lower sensitivity) were detected by using EFW >â 90th percentile, rather than EFW â 90th percentile were at increased risk of adverse perinatal outcomes according to all or some of the eight growth standards, respectively. The RR of a composite adverse perinatal outcome in pregnancies with EFW <â 10th percentile was higher for the mostâ stringent (NICHD) compared with the leastâ stringent (FMF) standard. The results of the complementary analysis of AUC suggest slightly improved detection of adverse perinatal outcome by more recent populationâ based (INTERGROWTHâ 21st) and customized (PRB/NICHD) standards compared with the Hadlock and FMF standards. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153734/1/uog20299.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153734/2/uog20299_am.pd

Distributed flow optimization and cascading effects in weighted complex networks

We investigate the effect of a specific edge weighting scheme $\sim (k_i k_j)^{\beta}$ on distributed flow efficiency and robustness to cascading failures in scale-free networks. In particular, we analyze a simple, yet fundamental distributed flow model: current flow in random resistor networks. By the tuning of control parameter $\beta$ and by considering two general cases of relative node processing capabilities as well as the effect of bandwidth, we show the dependence of transport efficiency upon the correlations between the topology and weights. By studying the severity of cascades for different control parameter $\beta$, we find that network resilience to cascading overloads and network throughput is optimal for the same value of $\beta$ over the range of node capacities and available bandwidth

Hypoxia induces dilated cardiomyopathy in the chick embryo: mechanism, intervention, and long-term consequences

Background: Intrauterine growth restriction is associated with an increased future risk for developing cardiovascular diseases. Hypoxia in utero is a common clinical cause of fetal growth restriction. We have previously shown that chronic hypoxia alters cardiovascular development in chick embryos. The aim of this study was to further characterize cardiac disease in hypoxic chick embryos. Methods: Chick embryos were exposed to hypoxia and cardiac structure was examined by histological methods one day prior to hatching (E20) and at adulthood. Cardiac function was assessed in vivo by echocardiography and ex vivo by contractility measurements in isolated heart muscle bundles and isolated cardiomyocytes. Chick embryos were exposed to vascular endothelial growth factor (VEGF) and its scavenger soluble VEGF receptor-1 (sFlt-1) to investigate the potential role of this hypoxia-regulated cytokine. Principal Findings: Growth restricted hypoxic chick embryos showed cardiomyopathy as evidenced by left ventricular (LV) dilatation, reduced ventricular wall mass and increased apoptosis. Hypoxic hearts displayed pump dysfunction with decreased LV ejection fractions, accompanied by signs of diastolic dysfunction. Cardiomyopathy caused by hypoxia persisted into adulthood. Hypoxic embryonic hearts showed increases in VEGF expression. Systemic administration of rhVEGF165 to normoxic chick embryos resulted in LV dilatation and a dose-dependent loss of LV wall mass. Lowering VEGF levels in hypoxic embryonic chick hearts by systemic administration of sFlt-1 yielded an almost complete normalization of the phenotype. Conclusions/Significance: Our data show that hypoxia causes a decreased cardiac performance and cardiomyopathy in chick embryos, involving a significant VEGF-mediated component. This cardiomyopathy persists into adulthood

Vasa previa in singleton pregnancies: diagnosis and clinical management based on an international expert consensus

Background: There are limited data to guide the diagnosis and management of vasa previa. Currently, what is known is largely based on case reports or series and cohort studies. Objective: This study aimed to systematically collect and classify expert opinions and achieve consensus on the diagnosis and clinical management of vasa previa using focus group discussions and a Delphi technique. Study design: A 4-round focus group discussion and a 3-round Delphi survey of an international panel of experts on vasa previa were conducted. Experts were selected on the basis of their publication record on vasa previa. First, we convened a focus group discussion panel of 20 experts and agreed on which issues were unresolved in the diagnosis and management of vasa previa. A 3-round anonymous electronic survey was then sent to the full expert panel. Survey questions were presented on the diagnosis and management of vasa previa, which the experts were asked to rate on a 5-point Likert scale (from "strongly disagree"=1 to "strongly agree"=5). Consensus was defined as a median score of 5. Following responses to each round, any statements that had median scores of ≤3 were deemed to have had no consensus and were excluded. Statements with a median score of 4 were revised and re-presented to the experts in the next round. Consensus and nonconsensus statements were then aggregated. Results: A total of 68 international experts were invited to participate in the study, of which 57 participated. Experts were from 13 countries on 5 continents and have contributed to >80% of published cohort studies on vasa previa, as well as national and international society guidelines. Completion rates were 84%, 93%, and 91% for the first, second, and third rounds, respectively, and 71% completed all 3 rounds. The panel reached a consensus on 26 statements regarding the diagnosis and key points of management of vasa previa, including the following: (1) although there is no agreement on the distance between the fetal vessels and the cervical internal os to define vasa previa, the definition should not be limited to a 2-cm distance; (2) all pregnancies should be screened for vasa previa with routine examination for placental cord insertion and a color Doppler sweep of the region over the cervix at the second-trimester anatomy scan; (3) when a low-lying placenta or placenta previa is found in the second trimester, a transvaginal ultrasound with Doppler should be performed at approximately 32 weeks to rule out vasa previa; (4) outpatient management of asymptomatic patients without risk factors for preterm birth is reasonable; (5) asymptomatic patients with vasa previa should be delivered by scheduled cesarean delivery between 35 and 37 weeks of gestation; and (6) there was no agreement on routine hospitalization, avoidance of intercourse, or use of 3-dimensional ultrasound for diagnosis of vasa previa. Conclusion: Through focus group discussion and a Delphi process, an international expert panel reached consensus on the definition, screening, clinical management, and timing of delivery in vasa previa, which could inform the development of new clinical guidelines