Effects of magnetic field on inflammation.

The effects of a 50 Hz magnetic field on experimentally-induced inflammation in rats were studied. Carrageenan edema was inhibited significantly by exposure to magnetic field for 3 h. Adjuvant-induced arthritis in rats was also suppressed by the magnetic field.     

Influence of an additional magnetic field on hornet nest architecture

Summary An additional horizontal magnetic field is lethal for adult hornets and larvae. The juvenile hornets, however, are capable of adapting to the additional magnetic field. They build combs commencing in the regions of high field intensity, and proceeding in the direction of the field intensity decrease.     

Drift of an erythrocyte flow line due to the magnetic field

Summary Drifts of erythrocyte-flow lines due to inhomogeneous magnetic field in a laminar flow in a buffer solution are shown for the first time, and are interpreted as being due to the paramagnetism of hemoglobins included in the erythrocytes. The drifts were dependent on the hematocrit of the flowing erythrocyte suspension.     

Drift of an erythrocyte flow line due to the magnetic field

Drifts of erythrocyte-flow lines due to inhomogeneous magnetic field in a laminar flow in a buffer solution are shown for the first time, and are interpreted as being due to the paramagnetism of hemoglobins included in the erythrocytes. The drifts were dependent on the hematocrit of the flowing erythrocyte suspension.     

Weak static magnetic fields increase the speed of circumnutation in cucumber (Cucumis sativus L.) tendrils

Tendrils are thread-like organs whose function is to support the stems of many species of climbing plants. Tendrils naturally move (circumnutate) in space. Individual tendrils of cucumber (Cucumis sativus L.) Poinset had the vertical component of their mean velocity vector of circumnutation changed when exposed to a range of weak static magnetic fields between 1 and 16 mT. The speed (modulus) of the velocity vector was significantly increased (p=0.016) in the vicinity of a magnet, but its direction did not show a definite trend with respect to the magnet. Although cucumber tendrils bear static positive charges, they did not behave as charged bodies do in a magnetic field, neither did they show a magnetotropic response. In fact, tendrils showed a nastic response to magnetism. Magnetic fields affected some processes underlying the movement of circumnutation, but no clear interpretation of them can be given presently on the basis of the known effects of magnetism on plants. It is clear that cucumber tendrils, because of some inherent susceptibility to magnetism or their particular size and shape, are very sensitive to relatively low static magnetic field strengths.     

Influence of the earth's magnetic field on the comb building orientation of hornets

Summary Introduction of a magnetic field that counteracts the vertical component of the earth's field, thereby creating a total zero field is lethal to juvenile hornets and completely disrupts the comb-building orientation of adult hornets. This suggests that the terrestrial magnetic field is the main guideline for vespan building orientation.     

A DNA extraction procedure practicable under field work conditions

Summary A DNA extraction procedure is described which is designed to be used in field work. A crude initial cell precipitate, which is easily obtained, may endure storage of months.Acknowledgment. The skilful technical assistance by MissB. Kunz is gratefully acknowledged.     

Lipids of guinea-pig alveolar macrophages

Zusammenfassung Lipidanalyse von Meerschweinchen-Makrophagen.

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Authors are grateful to Dr.O. Isler of F. Hoffmann La Roche Co. Ltd., Basle, for generous gifts of synthetic ubiquinone samples.     

乘波布局高超声速飞行器纵向静稳定特性分析

高超声速滑翔飞行器稳定性设计方法的研究具有重要应用价值.乘波体构型滑翔飞行器由于没有平尾且飞行在高空、高超声速条件下,其纵向静稳定特性与常规飞机有很大不同,对此传统飞行力学并无相应设计依据.在相切锥乘波体理论基础上,本文建立了计及流向一阶导数和二阶导数的微元计算模型,结合牛顿法、活塞理论、切楔/切锥法的理论推导与CFD数值计算,研究了典型二维剖面在高超声速、宽攻角范围下的纵向静稳定特性,从理论角度证明了沿流向＂下凸＂的流线特征有利于保证纵向静稳定,而＂上凹＂形状特征不利于纵向静稳定,该结论通过二维和三维算例得到了验证.以上述分析为基础,解释了基于锥型流的乘波体难以满足纵向静稳定性的物理原因,以及俯仰配平舵面可能对纵向静稳定性带来的影响,并提出了相应解决方案.进一步分析表明该结论适用于宽马赫数和宽高度范围,且黏性作用并不改变上述规律,相关结论可作为高超声速滑翔飞行器气动设计的参考.     

华夏农耕文化探源--兼论以粮为纲

华夏农耕文化发源于黄河、长江中下游冲积平原的林缘地带，由此向外扩展。伏教氏是脱胎于游猎采集而进入家畜饲养业的农业始祖。由满足畜牧业种草进而作物栽培的神农氏时代相继发生。农耕必然与定居相伴，以鸟巢为滥筋的木架民居结构于是出现，有巢氏与神农氏的时代同步。从此揭开了华夏民族以耕战为特色的农耕文化长卷。以商鞅“垦草”为代表的农耕思想，代代相传，直到晚近的“以粮为纲”，以谷物生产为主的农业系统和农耕文化盘踞中国数千年，对土地资源造成难以估量的损失。工商业在春秋战国末年曾经有过生机勃勃的萌芽时期，文化科技也随之繁荣，史称“百家争鸣”黄金时代。但商业发展威胁了封建贵族，重士农，轻工商的思想逐步占据上风，到了初汉，从思想到社会，形成颇为完整的尊孔押商体系，从此中国科技也失去了生长的沃土。     

Molecular basis of mycobacterial survival in macrophages

Macrophages play an essential role in the immune system by ingesting and degrading invading pathogens, initiating an inflammatory response and instructing adaptive immune cells, and resolving inflammation to restore homeostasis. More interesting is the fact that some bacteria have evolved to use macrophages as a natural habitat and tools of spread in the host, e.g., Mycobacterium tuberculosis (Mtb) and some non-tuberculous mycobacteria (NTM). Mtb is considered one of humanity’s most successful pathogens and is the causal agent of tuberculosis, while NTMs cause opportunistic infections all of which are of significant public health concern. Here, we describe mechanisms by which intracellular pathogens, with an emphasis on mycobacteria, manipulate macrophage functions to circumvent killing and live inside these cells even under considerable immunological pressure. Such macrophage functions include the selective evasion or engagement of pattern recognition receptors, production of cytokines, reactive oxygen and nitrogen species, phagosome maturation, as well as other killing mechanisms like autophagy and cell death. A clear understanding of host responses elicited by a specific pathogen and strategies employed by the microbe to evade or exploit these is of significant importance for the development of effective vaccines and targeted immunotherapy against persistent intracellular infections like tuberculosis.