Expression Patterns and Gonadotropin Regulation of the TGF-β II Receptor (Bmpr2) during Ovarian Development in the Ricefield Eel Monopterus albus

Bmpr2 plays a central role in the regulation of reproductive development in mammals, but its role during ovarian development in fish is still unclear. To ascertain the function of bmpr2 in ovarian development in the ricefield eel, we isolated and characterized the bmpr2 cDNA sequence; the localization of Bmpr2 protein was determined by immunohistochemical staining; and the expression patterns of bmpr2 in ovarian tissue incubated with FSH and hCG in vitro were analyzed. The full-length bmpr2 cDNA was 3311 bp, with 1061 amino acids encoded. Compared to other tissues, bmpr2 was abundantly expressed in the ovary and highly expressed in the early yolk accumulation (EV) stages of the ovary. In addition, a positive signal for Bmpr2 was detected in the cytoplasm of oocytes in primary growth (PG) and EV stages. In vitro, the expression level of gdf9, the ligand of bmpr2, in the 10 ng/mL FSH treatment group was significantly higher after incubation for 4 h than after incubation for different durations. However, bmpr2 expression in the 10 ng/mL FSH treatment group at 2 h, 4 h and 10 h was significantly lower. Importantly, the expression level of bmpr2 and gdf9 in the 100 IU/mL hCG group had similar changes that were significantly decreased at 4 h and 10 h. In summary, Bmpr2 might play a pivotal role in ovarian growth in the ricefield eel, and these results provide a better understanding of the function of bmpr2 in ovarian development and the basic data for further exploration of the regulatory mechanism of gdf9 in oocyte development.     

Identification of Molecular Determinants in iRhoms1 and 2 That Contribute to the Substrate Selectivity of Stimulated ADAM17

The metalloprotease ADAM17 is a key regulator of the TNFα, IL-6R and EGFR signaling pathways. The maturation and function of ADAM17 is controlled by the seven-membrane-spanning proteins iRhoms1 and 2. The functional properties of the ADAM17/iRhom1 and ADAM17/iRhom2 complexes differ, in that stimulated shedding of most ADAM17 substrates tested to date can be supported by iRhom2, whereas iRhom1 can only support stimulated shedding of very few ADAM17 substrates, such as TGFα. The first transmembrane domain (TMD1) of iRhom2 and the sole TMD of ADAM17 are important for the stimulated shedding of ADAM17 substrates by iRhom2. However, little is currently known about how the iRhoms interact with different substrates to control their stimulated shedding by ADAM17. To provide new insights into this topic, we tested how various chimeras between iRhom1 and iRhom2 affect the stimulated processing of the EGFR-ligands TGFα (iRhom1- or 2-dependent) and EREG (iRhom2-selective) by ADAM17. This uncovered an important role for the TMD7 of the iRhoms in determining their substrate selectivity. Computational methods utilized to characterize the iRhom1/2/substrate interactions suggest that the substrate selectivity is determined, at least in part, by a distinct accessibility of the substrate cleavage site to stimulated ADAM17. These studies not only provide new insights into why the substrate selectivity of stimulated iRhom2/ADAM17 differs from that of iRhom1/ADAM17, but also suggest new approaches for targeting the release of specific ADAM17 substrates.     

Challenges and recent progress in thermal management with heat pipes for lithium-ion power batteries in electric vehicles

Electric vehicles(EVs) are globally undergoing rapid developments, and have great potentials to replace the traditional vehicles based on fossil fuels. Power-type lithium-ion batteries(LIBs) have been widely used for EVs, owing to high power densities,good charge/discharge stability, and long cycle life. The driving ranges and acceleration performances are gaining increasing concerns from customers, which depend highly on the power level of LIBs. With the increase in power outputs, rising heat generation significantly affects the battery performances, and in particular operation safety. Meanwhile, the cold-start performance is still an intractable problem under extreme conditions. These challenges put forward higher requirements for a dedicated battery thermal management system(BTMS). Compared to traditional BTMSs in EVs, the heat pipe-based BTMS has great application prospects owing to its compact structure, flexibility, low cost, and especially high thermal conductivity. Encompassing this topic, this review first introduces heat generation phenomena and temperature characteristics of LIBs. Multiple abuse conditions and thermal runaway issues are described afterward. Typical cooling and preheating methods for designing a BTMS are also discussed. More emphasis on this review is put on the use of various heat pipes for BTMSs to enhance the thermal performances of LIBs. For lack of wide application in actual EVs, more efforts should be made to extend the use of heat pipes for constructing an energy-efficient, cost-effective, and reliable BTMS to improve the performances and safety of EVs.     

基于 RLS-SVR 的光伏并网变流器 早期故障预测方法研究

针对光伏并网变流器故障预测问题,提出了基于鲁棒最小二乘-支持向量回归(RLS-SVR)的早期故障预测方法.从系统层面分析了光伏并网变流器脆弱元件退化互相耦合机理及对系统状态特征和早期故障特征选取的影响,进而提出了以特征相对变化量表征变流器状态的电路故障预测方法.为了减小工作条件对特征退化预测的影响,方法首先采用RLS-...     

吉林省白山市大横路铜钴矿的工艺矿物学特征

在我国,大横路铜钴矿床是迄今为止发现的唯一的大型独立钴矿床。为开发利用,对它进行了系统的工艺矿物学研究,并评估了影响回收指标的矿物学因素。该工作在国内尚属首次。所获结果不仅对选冶工艺研究有指导意义,而且也丰富了矿区矿物学资料。     

铝电解槽针振信息元分析和诊断系统的开发与应用

针对铝电解槽针振信息元诊断手段的不足,提出基于小波-神经网络技术的铝电解槽针振信息元分析与诊断的新方法。获取5种针振信息元的特征波谱作为神经网络的训练样本,建立神经网络诊断系统。分析了系统软硬件结构及其特点,并在350kA预焙铝电解槽上进行实验和仿真。实验证明该系统有很高的精度,且具有很好的应用价值。     

惯性圆锥破碎机运动学和动力学分析

惯性圆锥破碎机是具有独特原理和结构的高效超细粉碎设备。本文通过对惯性圆锥破碎机破碎机理的研究,对该破碎机的运动学和动力学作了较全面的分析,建立了惯性圆锥破碎机的运动学模型,推导出惯性圆锥破碎机的运动学和动力学公式,得出破碎力计算公式,并运用运动学和动力学分析了惯性圆锥破碎机的工作特点。