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This study aimed to explore the significance of renal Doppler ultrasound in evaluating systemic and renal perfusion in sepsis patients before and after fluid resuscitation.Forty sepsis patients admitted to the Department of Intensive Medicine and intensive care unit (ICU) of the Fourth Hospital of Hebei Medical University from June 2014 to December 2014 were enrolled in this study, and 35 patients were included in the final analysis. These patients were divided into positive and negative fluid responsiveness groups. They were also divided into an acute kidney injury (AKI) group and a non-AKI group according to changes in creatinine and urine volume. The correlations of the changes in hemodynamics before and after fluid resuscitation in each group with the changes in renal resistance index (RRI) and renal blood flow (RBF) grades were evaluated.Before and after fluid resuscitation, the heart rate (HR), blood creatinine (Cre), and lactate (Lac) levels of all patients, including the patients in the positive fluid responsiveness group decreased, and the stroke volume (SV) and central venous pressure (CVP) increased. Only HR decreased in the negative fluid responsiveness group. In the AKI group, HR, Cre, and Lac decreased, while in the non-AKI group, HR decreased, but CVP and SV increased. There were differences between HR, Lac, and change rate of Lac (Lac%) after fluid resuscitation for the positive and negative fluid responsiveness groups. There was no statistical difference between the RRI values of each group before and after fluid resuscitation. The RRI values of the AKI group were higher than those of the non-AKI group, while the AKI group's RBF grades were lower than those of the non-AKI group. The change rate of RRI (RRI%) was higher in the AKI group than in the non-AKI group. Except for the negative fluid responsiveness group, the RBF grade of each group increased.The approach of RBF classification based on Doppler ultrasound can be used to evaluate the systemic and renal perfusion of patients with severe sepsis before and after fluid resuscitation, while the RRI value cannot be used for evaluation. However, the RRI value can be used as a dynamic index for the evaluation of renal perfusion in patients with AKI.

Summary The main objectives of this study were to estimate the age, growth, mortality and population structure of silver croaker Pennahia argentata (Houttuyn, 1782) and red bigeye Priacanthus macracanthus Cuvier, 1829 and to explore the factors causing the fluctuation of the fish populations and the ecological parameters. The two species were randomly sampled, with 80~120 individuals of each species captured every month from a single trawler fishery (mesh size 250 mm), March to November 2006, in the north-central Taiwan Strait. A total of 994 speciments of silver croaker and 851 speciments of red bigeye were collected. Compared with previous studies, the mean length and weight, mean age, the minimum size at first sexual maturity, the asymptotic length (L∞) and weight (W∞) of the two species has decreased in recent decades, indicating that the populations were younger, smaller and earlier in sexual maturity. Meanwhile, the growth coefficient (K) increased, the mortality coefficients (Z, F, M) were higher, and the exploitation rate (E) indicated overfishing. Fishing is a key driving force that can cause abundant fluctuations and changes in ecological characteristics in these two demersal fishes in this area. Accordingly, the traditional fishery management approach, such as the reduction in fishing effort, coupled with the Ecosystem-based Fishery Management (EBFM) should be implemented to achieve sustainable demersal fisheries.

Through visualization and measurement on the cylinder-plate junction flow, we show the horseshoe vortices can be significantly modified by altering the section shape of the cylinder. Both smoke-wire and Laser-Induced-Fluorescence (LIF) are employed to visualize the vortex structures. Laser Doppler velocimeter is used to measure the velocity field in the symmetry plane upstream of the cylinder. Electrical pressure-scanning valve is applied to acquire the pressure on the plate. It is found that, the sharper the frontal shape of the cylinder, the closer the vortex shedding position and the primary horseshoe vortex location to the cylinder. We quantitatively show the variation of the scale and strength of the primary horseshoe vortex, as well as the maximum wall shear stress, when the section shape of the cylinder is varied. The reduced streamwise adverse pressure gradient explains why the horseshoe vortices are significantly suppressed when the frontal shape of the cylinder becomes sharper. At last, we present a swept thin cylinder installed in front of the primary cylinder can be used to suppress the horseshoe vortices, which is greatly effective and easy to implement.

This paper reports a numerical study of a two‐dimensional time‐dependent viscous flow past a rectangular bluff body with a Reynolds number Re = 6 073 based on bluff body height installed in a flow duct. The leading edge of the bluff body takes a semi‐circular profile. The governing equations of the flow are solved with large‐eddy simulation (LES) using a commercial computational fluid dynamics software FLUENT. The focus of the present study is to explore the effects of the ratio of the height of the bluff body H and the separation D between the bluff body and the duct wall surface. The numerical simulations are validated with the results obtained from a separate wind‐tunnel experiment. Numerical simulations with various D/H are carried out. The numerical results show that the mean and instantaneous flow quantities are strongly dependent on the ratio D/H. The suppression effects of vortex shedding by the neighboring duct wall are highlighted by comparing the unsteady flow structure topology, dominant Strou...

The residual dynamics of flumioxazin in soil and soybean were determined with HPLC, using a Zorbax SIL column and methylene dichloride-methanol (99.5:0.5, V/V) as mobile phase. A method for pretreatment of samples and analysis was established. Recoveries of flumioxazin in soil, green soybean and soybean were 84.82%-85.63%, 88.79%-94.00% and 93.70%-94.48%, respectively. Flumioxazin degrades relatively slowly and its half-life in soil was 10.0-10.5 days, but in the soil, green soybean and soybean residual flumioxazin was not detected. The results showed that the residual pollution of flumioxazin is negligible, so the application of flumioxazin is safe for the soil and soybean.