The Chemical Biology of Phosphoinositide 3‐Kinases

Since its discovery in the late 1980s, phosphoinositide 3‐kinase (PI3K), and its isoforms have arguably reached the forefront of signal transduction research. Regulation of this lipid kinase, its functions, its effectors, in short its entire signaling network, has been extensively studied. PI3K inhibitors are frequently used in biochemistry and cell biology. In addition, many pharmaceutical companies have launched drug‐discovery programs to identify modulators of PI3Ks. Despite these efforts and a fairly good knowledge of the PI3K signaling network, we still have only a rudimentary picture of the signaling dynamics of PI3K and its lipid products in space and time. It is therefore essential to create and use novel biological and chemical tools to manipulate the phosphoinositide signaling network with spatial and temporal resolution. In this review, we discuss the current and potential future tools that are available and necessary to unravel the various functions of PI3K and its isoforms.     

Design of conical DRH antennas for K and Ka frequency bands

Two conical double‐ridged horn (DRH) antennas for K and Ka frequency bands are presented. Detailed simulation and experimental investigations are conducted to understand their behaviors and optimize for broadband operation. The designed antennas were fabricated with 0.01 mm accuracy and satisfactory agreement of computer simulations and experimental results was obtained. The designed conical DRH antennas have voltage standing wave ratio (VSWR) less than 2.1 and 2.2 for the frequency ranges of 18–26.5 GHz (K band) and 26.5–40 GHz (Ka band), respectively. Meanwhile, the proposed antennas exhibit low cross‐polarization, low sidelobe level, and simultaneously achieve slant polarization as well as symmetrical radiation patterns in the entire operating bandwidth. An exponential impedance tapering is used at the flare section of the horns. Moreover, a new cavity back with a conical structure is used to improve the VSWR. Numerous simulations via Ansoft HFSS and CST Microwave Studio CAD tools have been made to optimize the VSWR performance of the designed antennas. Simulation results show that the VSWR of the proposed antennas is sensitive to the probe spacing from the ridge edge and the cavity back structure. The designed conical DRH antennas are most suitable as a feed for the reflectors of radar systems and satellite applications. Results for VSWR, far‐field E‐plane and H‐plane radiation patterns, and gain of the designed antennas are presented and discussed. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.     

连铸机结晶器振动变频器升级改造

介绍现场工作人员针对现场设备的设计缺陷,充分利用现有设备条件,对设备升级改造以及选型计算依据,对解决武钢炼钢总厂三分厂1号连铸机结晶器振动变频器难以满足生产需要的问题,具有很好的借鉴意义。     

New Automated Microwave Heating Process for Cooking and Pasteurization of Microwaveable Foods Containing Raw Meats

ABSTRACT: A new microwave heating process was developed for cooking microwaveable foods containing raw meats. A commercially available inverter-based microwave oven was modified for pasteurization of mechanically tenderized beef, inoculated with Escherichia coli O157:H7 (approximately 5 log₁₀ CFU/g) and packaged in a 12-oz CPET tray containing 150-mL de-ionized water. The new microwave heating system was equipped with an infrared sensor and a proportional feedback mechanism to allow temperature controlled microwave heating. A 2-stage heating strategy was adopted to cook the product. In the primary heating stage, the sample surface temperature was increased to an initial temperature set-point (ITSP, 65, 70, 75, or 80 °C). In the secondary heating stage, the heating was continued with a small fraction of microwave power. The effect of ITSP, hold time (0 to 3 min), and sample elevation (0, 0.03, and 0.07 m above turntable) on inactivation of E. coli O157:H7 and background microflora was evaluated. It was observed that only a small number (approximately 1.3 logs) of E. coli O157:H7 and background microflora were inactivated in the primary heating stage. The elevation 0.07 m, which was in the proximity of the geometric center of the metal cavity, was more effective in inactivating both E. coli O157:H7 and background microflora. Substantially more bacteria were inactivated in the secondary heating stage. Complete inactivation of E. coli and background microflora was observed with heating at temperatures above 70 °C for more than 1 min. This study demonstrated a new approach for ensuring the safety of microwaveable products containing raw meats.     

Effect of red mold rice on blood coagulation and anticoagulation factors in a rat model of hyperlipidemia

The bioactive monacolin K found in red mold rice (RMR) is identical in structure to lovastatin, and has the effect of lowering the cholesterol level in human blood. Statins not only lower atherosclerosis caused by thrombus, but also reduce the death rate from coronary artery disease. This study was designed to evaluate the effects of Monascus purpureus NTU 803 fermented-RMR on blood coagulation and anticoagulation factors in hyperlipidemic rats. Rats were fed a high-lipid diet for 8 weeks to induce hyperlipidemia and fed various doses of RMR. The results showed that RMR prolonged the bleeding time of the rats, inhibited platelet coagulation, lowered the fibrinogen content in the blood, increased the antithrombin III and protein C content in the blood, and reduced lipid plaque in the aorta. RMR was effective for preventing the formation of thrombus and reducing the occurrence of atherosclerosis.     

某地含钾火山岩释钾能力实验研究

某地含钾火山岩储量大，易开采，主要矿石为沸石，透长石，黑云母以及玻璃质等，平均含氧化钾３．３１％，通过初步实验速效钾含量达到供钾潜力的中－极高水平，可直接农用，代替部分化肥，在喀斯特红土地区，效果更加显著。     

两种不同冷却方式在高压变频应用中的对比分析

本文介绍了两种不同冷却方式在600MW机组一次风机变频节能改造中的应用实例，对空一水冷却系统和密闭冷却系统两种冷却方式进行技术方案和经济效益对比分析，阐述了其中存在的差异和特点。为高压变频节能改造中降低冷却系统能耗，提高系统安全可靠性，提供重要的可借鉴经验。     

软启动与变频调速装置在矿区的应用

本文简介一般软启动与变频调速装置的适应性、运行方式、工作原理，以及大功率软启动与变频调速装置工作原理与附加装置改善谐波干扰的措施、应用效果。     

The impact of divorce precedents on the Japanese divorce rate

This paper undertakes a time series analysis of the Japanese divorce rate using annual data over the period 1964–2006. One of the key innovations of the paper is to use court decisions on divorce disputes to construct an index that seeks to measure how the probability of success in a divorce suit has changed over time. The computed index suggests that if it is the culpable party lodging the divorce suit, the probability of the suit being successful has clearly increased over time. The probability of winning a divorce suit appears to be an important factor in explaining the long-run rise in the Japanese divorce rate. The divorce rate also appears to be counter-cyclical.