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Weaning is considered to be one of the most critical periods in pig production, which is related to the economic benefits of pig farms. However, in actual production, many piglets are often subjected to weaning stress due to the sudden separation from the sow, the changes in diet and living environment, and other social challenges. Weaning stress often causes changes in the morphology and function of the small intestine of piglets, disrupts digestion and absorption capacity, destroys intestinal barrier function, and ultimately leads to reduced feed intake, increased diarrhea rate, and growth retardation. Therefore, correctly understanding the effects of weaning stress on intestinal health have important guiding significance for nutritional regulation of intestinal injury caused by weaning stress. In this review, we mainly reviewed the effects of weaning stress on the intestinal health of piglets, from the aspects of intestinal development, and intestinal barrier function, thereby providing a theoretical basis for nutritional strategies to alleviate weaning stress in mammals in future studies. [ABSTRACT FROM AUTHOR]

In clinical practice, ovarian pregnancy is extremely rare and is always found to be ruptured. A definitive diagnosis for ruptured ovarian pregnancy is difficult to obtain. We present two cases of unruptured ovarian pregnancies detected during laparoscopy and review existing literature to better understand the clinical characteristics of ectopic pregnancies in this rare site. Intrauterine devices, assisted reproductive technology, and intrauterine operations are all high-risk factors in ovarian pregnancy. Moreover, menopause, abdominal pain, and vaginal bleeding are clinical manifestations. Ovarian pregnancy can be diagnosed using serum hCG, transvaginal ultrasound, and magnetic resonance imaging. Laparoscopy is the treatment of choice for ovarian pregnancy. It is recommended that the intact gestational sac be excised and the ovarian function be protected to the greatest extent possible during the operation. More definitive diagnosis of ovarian pregnancy must be reported in order to gain a better understanding of ovarian pregnancy. [ABSTRACT FROM AUTHOR]

[Objectives] The purpose was to analyze and predict the mechanism of Fuxin decoction in the treatment of heart failure based on network pharmacology. [Methods] Relevant tools and methods of network pharmacology were used to obtain the active ingredients and action targets of Fuxin decoction and action targets of heart failure, find out the key targets and core clusters of Fuxin decoction on heart failure, and analyze related signal pathways, to explore possible molecular mechanisms. [Results] A total of 53 active ingredients and 224 action targets of Fuxin decoction, 1 010 heart failure-related target genes, and 94 drug-disease directly acting targets were obtained. From the PP1 network constructed, 225 key targets and a core cluster composed of 56 nodes and 297 interactions were screened out. Association with tumors, glutamate synapse and other related pathways and related genes such as adenylate cyclase and MAPK were known. [Conclusions] The mechanism of Fuxin decoction in the treatment of heart failure is related to βARs-G protein-adenylate cyclase, P13K-Akt signaling pathway and HSP90, MAPK and other proteins. [ABSTRACT FROM AUTHOR]

During the working period of decay heat removal system, the flow rate of liquid sodium in wire-wrapped fuel assembly is very low, generally Re < 1000. In the present study, both experimental methods and numerical simulation methods are applied. First, water experiment of 37-pin wire-wrapped rod bundle was carried out. Then, the numerical simulation study was carried out, the experimental data and the numerical simulation results were compared and analyzed, and a suitable turbulence model was selected to simulate the liquid sodium medium. Finally, numerical simulations under different boundary conditions were performed. Results indicate that except for the low Reynolds number k-e turbulence model, other turbulence models have little difference with the experimental results. The results of realizable k-e turbulence model are the most close to the experimental results. Compared with the friction factor obtained by using water medium and liquid sodium medium, the calculation results of water medium and sodium medium under the same condition are basically consistent, with the deviation within 1%. The reason is that the velocity of water is higher than sodium medium at the same Reynolds number, and the transverse disturbance caused by helical wire is larger. [ABSTRACT FROM AUTHOR]

The turbulence model fails in supercritical fluid-flow and heat transfer simulation, owing to the drastic change of thermal properties. The inappropriate buoyancy effect model and the improper turbulent Prandtl number model are several of these factors lead to the original low-Reynolds number turbulence model unable to predict the wall temperature for vertically heated tubes under the deteriorate heat transfer conditions. This paper proposed a simplified improved method to modify the turbulence model, using the generalized gradient diffusion hypothesis approximation model for the production term of the turbulent kinetic energy due to the buoyancy effect, using a turbulence Prandtl number model for the turbulent thermal diffusivity instead of the constant number. A better agreement was accomplished by the improved turbulence model compared with the experimental data. The main reason for the over-predicted wall temperature by the original turbulence model is the misuse of the buoyancy effect model. In the improved model, the production term of the turbulent kinetic energy is much higher than the results calculated by the original turbulence model, especially in the boundary- layer. A more accurate model for the production term of the turbulent kinetic energy is the main direction of further modification for the low Reynolds number turbulence model. [ABSTRACT FROM AUTHOR]

Condensates and light oils are generally characterized by high maturity, low concentration of sterane and terpane biomarkers and low content of non-hydrocarbon fraction. As a result, some commonly-used sterane, terpane and carbazole migration parameters in conventional oil reservoirs may have a certain limitation in condensate and light oil reservoirs for their poor signal-noise ratios in the gas chromatography-mass spectrometry (GC-MS). Naphthalene, phenanthrene and their methylated substituents, however, are present in significant concentrations in condensates and light oils. Taking the Fushan depression (in the Beibuwan Basin, Northern South China Sea) as an example, this paper attempts for the first time to use polycyclic aromatic hydrocarbon (PAH)-related parameters to trace migration directions and filling pathways for condensate and light oil reservoirs. The result shows that TMNr (i.e. 1,3,7-TMN/ (1,3,7-TMN + 1,2,5-TMN), TMN: trimethylnaphthalene)), MPI-1 (i.e. 1.5×(2-MP + 3-MP)/(P + 1-MP + 9-MP), P: phenanthrene MP: methylphenanthrene), MN/DMN (σmethylnaphthalene/σdimethylnaphthalene, %) and MN/TMN (σmethylnaphthalene/σtrimethylnaphthalene, %) can be used to trace the filling pathways of condensate and light oil reservoirs. These parameters, together with geological consideration and other bulk oil properties (e.g. the gas to oil ratio and density), suggest that the condensates and light oils in the Huachang oil and gas field are mainly sourced from the Bailian sag that is located to the northeast of the Huachang uplift in the Fushan depression. [ABSTRACT FROM AUTHOR]

Ultra-thin PtxFey-nanowires (PtxFey-NWs) with a diameter of 2-3 nm were successfully prepared through a solution-phase reduction method at Pt-Fe compositions from 1:1 to 2:1. The carbon supported PtxFey-NWs (PtxFey-NWs/C) demonstrated higher oxygen reduction reaction (ORR) activity and better electrochemical durability than conventional Pt/C catalyst. After 1000 cycles of 0-1.3 V (versus RHE), the relative electrochemical surface area (ECSA) of Pt2Fe1-NW/C dropped down to 46%, which was two times better than Pt/C catalyst, and the mass activity at 0.85 V (versus RHE) for Pt1Fe1-NW/C was 39.9 mA mg [?] 1-Pt, which is twice that for Pt/C (18.6 mA mg [?] 1-Pt). [ABSTRACT FROM AUTHOR]