The mutual influence of aircraft aerodynamics and ship hydrodynamics in theory and experiment

As early as 1784, sharp-eyed engineers and scientists noted striking similarities between the dynamics of seagoing vessels and aerial vehicles. By the early twentieth century, naval engineers and scientists were developing and designing airplanes and dirigibles using empirical principles derived from naval architecture. Several key researchers in aerodynamics began their career as naval architects (David A. Taylor, William F. Durand and Jerome C. Hunsaker) and carried out their experiments in ship testing facilities. By the 1930s, however, the transfer of knowledge was irrevocably reversed as empiricism gave way to more fundamental, physics-based research. The rapid evolution of complex aircraft systems and flight envelopes led to new theoretical developments in aerodynamics and maneuvering, which quickly found their way into naval ship design. The theoretical and experimental results for airfoils, rigid airships and fixed-wing aircraft developed by Ludwig Prandtl, Theodore von Kármán, Max M. Munk and Hilda M. Lyon were employed in the hydrodynamic development of surface ships and submarines. This paper examines how the ideas, concepts and data from one discipline influenced the other and explores the processes by which that knowledge was transferred between disciplines.     

Neuroanatomy and neurochemistry of sleep

Sleep is regulated by homeostatic and circadian factors, and the regulation of sleep of mammals shares many molecular properties with the rest state of submammalian species. Several brain structures take part in waking: the basal forebrain, posterior and lateral hypothalamus, and nuclei in the tegmentum and pons. Active sleep mechanisms are located to the preoptic/anterior hypothalamic area. In addition to acetylcholine and monoamines, glutamate and hypocretin/orexin are important waking factors. Gamma-aminobutyric acid and several peptide factors, including cytokines, growth hormone-releasing hormone and prolactin, are related to sleep promotion. Adenosine is an important homeostatic sleep factor acting in basal forebrain and preoptic areas through A1 and A2A receptors. Prolonged waking activates inducible nitric oxide synthase in the basal forebrain, which through energy depletion causes adenosine release and recovery sleep. Numerous genes have been found differentially displayed in waking compared with sleep, and they relate to neural transmission, synaptic plasticity, energy metabolism and stress protection. The genetic background of a few sleep disorders has been solved.     

α-Actinin structure and regulation

Alpha-actinin is a cytoskeletal actin-binding protein and a member of the spectrin superfamily, which comprises spectrin, dystrophin and their homologues and isoforms. It forms an anti-parallel rod-shaped dimer with one actin-binding domain at each end of the rod and bundles actin filaments in multiple cell-type and cytoskeleton frameworks. In non-muscle cells, alpha-actinin is found along the actin filaments and in adhesion sites. In striated, cardiac and smooth muscle cells, it is localized at the Z-disk and analogous dense bodies, where it forms a lattice-like structure and stabilizes the muscle contractile apparatus. Besides binding to actin filaments alpha-actinin associates with a number of cytoskeletal and signaling molecules, cytoplasmic domains of transmembrane receptors and ion channels, rendering it important structural and regulatory roles in cytoskeleton organization and muscle contraction. This review reports on the current knowledge on structure and regulation of alpha-actinin.     

The effect of the phytoalexins,lubimin, (−)-maackiain,pinosylvin, and the related compounds dehydroloroglossol and hordatine M on human lymphoblastoid cell lines

Summary We have tested the effect of the phytoalexins lubimin, (–)-maackiain and pinosylvin and the related compounds dehydroloroglossol and hordatine M on the growth of the human lymphoblastoid cell lines Molt and Raji. (–)-maackiain, pinosylvin and dehydroloroglossol showed significant growth inhibitory action on the cells. Suppression of [³H] thymidine and [³H] leucine uptake was tested and noted in pinosylvin and dehydroloroglossol. The phytoalexins and related compounds are widespread in plants and provide a potential source of antineoplastic substances.We would like to acknowledge the assistance of J. Hux in preparing the phytoalexins and related compounds. This work was supported by a grant from National Health and Welfare Canada. Correspondence to Dr. L. Skinnider, Department of Pathology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7M OWO.     

高校产学研一体化发展的实践与前瞻

本文探讨我国高校产学研一体化发展的必要性、可行性及其前景。从人类社会发展的历史特点入手，并借鉴了美国硅谷发展的经验和我国改革开放推进社会主义市场发展的需求，对高校产学研一体化发展的道路作了论述。针对目前高校产学研一体化中存在的问题，作者提出了加速高校产学研一体化发展的四条建议：1，高校产学研一体化发展必须转变观念，积极参与社会大循环；2，推进高校产学研一体化要有过硬的产品和准确的市场定位；3，高校产学研一体化发展要依托高科技园区，切实解决经费投入问题；4，高校产学研一体化发展要突出以人为本的思想，努力造就发明家和企业家。     

Triacylglycerol hydrolase: role in intracellular lipid metabolism

Recent scientific advances have revealed the identity of several enzymes involved in the synthesis, storage and catabolism of intracellular neutral lipid storage droplets. An enzyme that hydrolyzes stored triacylglycerol (TG), triacylglycerol hydrolase (TGH), was purified from porcine, human and murine liver microsomes. In rodents, TGH is highly expressed in liver as well as heart, kidney, small intestine and adipose tissues, while in humans TGH is mainly expressed in the liver, adipose and small intestine. TGH localizes to the endoplasmic reticulum and lipid droplets. The TGH genes are located within a cluster of carboxylesterase genes on human and mouse chromosomes 16 and 8, respectively. TGH hydrolyzes stored TG, and in the liver, the lipolytic products are made available for VLDL-TG synthesis. Inhibition of TGH activity also inhibits TG and apolipoprotein B secretion by primary hepatocytes. A role for TGH in basal TG lipolysis in adipocytes has been proposed. TGH expression and activity is both developmentally and hormonally regulated. A model for the function of TGH is presented and discussed with respect to tissue specific functions.     

Calcium and magnesium deficiency and C3 fraction of complement]

The third (C3) and fourth (C4) components of complement and C3 proactivator (C3PA) were determined in 55 children with low serum levels of calcium and magnesium and 30 normal children. The concentrations of serum C3, C4 and C3PA were significantly reduced in children with double deficiences of calcium and magnesium. There were significant correlations between calcium and C3 and magnesium and C3PA. The relations between calcium, magnesium and the classical or alternate pathway of complement systems are discussed.     

The effect of the phytoalexins, lubimin, (-)-maackiain, pinosylvin, and the related compounds dehydroloroglossol and hordatine M on human lymphoblastoid cell lines

We have tested the effect of the phytoalexins lubimin, (-)-maackiain and pinosylvin and the related compounds dehydroloroglossol and hordatine M on the growth of the human lymphoblastoid cell lines Molt and Raji. (-)-maackiain, pinosylvin and dehydroloroglossol showed significant growth inhibitory action on the cells. Suppression of [3H] thymidine and [3H] leucine uptake was tested and noted in pinosylvin and dehydroloroglossol. The phytoalexins and related compounds are widespread in plants and provide a potential source of antineoplastic substances.     

Gametes contain angiotensin converting enzyme (kininase II)

Summary The localization of angiotensin converting enzyme (ACE) in the gonads of the normal rabbit was studied by immunofluorescence and immunoelectron microscopy. The enzyme is present in the cytoplasm of testicular spermatids and of epididymal and ejaculated spermatozoa, and on the surface of follicular and tubal cocytes. These findings support the hypothesis that ACE has a role in gamete maturation and in fertilization.Acknowledgments. This study was supported by NIH grant AM36807 and by grants from the American Heart Association, the Joe and Emily Lowe Foundation, and the Dana Foundation. We thank L. Fernandez, B. Luders, I. Pawlowski, and K. Schwegler for technical assistance.     

Circling behavior in mice and rats: possible relationship to isolation-induced aggression

The relationship between circling behavior (rotation), isolation, and aggression was investigated in normal male mice and rats. Initially the animals were tested for spontaneous nocturnal rotation, then conspecific aggression and muricidal behavior was observed for mice and rats respectively. Subsequently, animals were paired on the basis of net nocturnal rotations and either group-housed or individually housed. Four weeks later all animals were retested for the same behaviors. Spontaneous nocturnal rotation increased significantly for the isolated mice but not for the group-housed animals. Moreover, 9 of the 10 isolates became aggressive and their net rotations were significantly and positively correlated with the number of biting attacks. None of the group-housed mice became aggressive. Rats, on other hand, showed a decrease in rotation and a relationship between rotation and muricidal behavior was not evident. The possible relationship between circling behavior, aggression, and territoriality is discussed.     

Development of DNA probes for cytotoxin and enterotoxin genes in enteric bacteria

DNA probes to identify the genes encoding toxins in enteric bacteria have been developed. Use of these probes reduces the number of animals required for toxicity testing, as suspect bacteria can be directly tested for the presence of toxin. We have augmented the gene probes available by developing probes against the Escherichia coli enterotoxin LTII and shiga toxin from Shigella dysenteriae 1. The LTII gene from E. coli 357900 was identified and characterised and a suitable internal probe was obtained. The LTII gene was found not to be common among enterobacteriae from various geographical locations. Isolates predominately of animal origin from Nigeria and Thailand hybridized with the probe. The shiga toxin gene was isolated from S. dysenteriae 1 by a combination of in vivo and in vitro methods. An internal probe was identified and used against different serogroups of Shigella and E. coli isolates. The probe was found to hybridize with S. dysenteriae 1 isolates and also some S. flexneri and S. sonnei strains. Representatives were tested for toxin production and found to produce toxin at low levels.     

Slice cultures of cerebellar,hippocampal and hypothalamic tissue

Summary Cerebellar, hippocampal and hypothalamic slices prepared from newborn and 7-day-old rats were cultured by means of the roller-tube technique. Identification of cells was made easier by the fact that at least part of the characteristic cytoarchitecture of the tissue was preserved in vitro. Cerebellar Purkinje cells and neurones of the deep cerebellar nuclei were recognized on the basis of their size, their location within the culture and their dendritic arborization. Pyramidal cells of all hippocampal subfields displayed their characteristic basal and apical dendritic trees with numerous spinous processes. Hippocampal granule cells gave rise to a monopolar dendritic arbor; their axons terminated in the dentate hilus and CA3 region. Golgi-like immuniperoxidase staining allowed localization of groups of neurophysin-positive neurones in slices prepared from the anterior hypothalamus. These neurones, bilaterally bordering the third ventricle, usually displayed a simple dendritic arborization and fine beaded axons.—Cultivation of brain slices prepared from young rats offers particular advantages in that the cultured cells are organized in an organotypic monolayer and individual living neurones may be directly visualized.Acknowledgments. I would like to thank Dr J. Zimmer and Dr M. Sofroniew for their valuable help with the Timms and immunoperoxidase staining techniques and Mr R. Schlichter and L. Wohlfart for illustrating the culture procedure. The excellent technical assistance of Ms L. Rietschin and E. Hoffmann is gratefully acknowledged.     

Into the ‘regions of physical and metaphysical chaos’: Maxwell’s scientific metaphysics and natural philosophy of action (agency,determinacy and necessity from theology,moral philosophy and history to mathematics,theory and experiment)

Maxwell’s writings exhibit an enduring preoccupation with the role of metaphysics in the advancement of science, especially the progress of physics. I examine the question of the distinction and the proper relation between physics and metaphysics and the way in which the question relies on key notions that bring together much of Maxwell’s natural philosophy, theoretical and experimental. Previous discussions of his attention to metaphysics have been confined to specific issues and polemics such as conceptions of matter and the problem of free will. I suggest a unifying pattern based on a generalized philosophical perspective and varying expressions, although never a systematic or articulated philosophical doctrine, but at least a theme of action and active powers, natural and human, intellectual and material, with sources and grounds in theology, moral philosophy and historical argument. While science was developing in the direction of professional specialization and alongside the rise of materialism, Maxwell held on to conservative intellectual outlook, but one that included a rich scientific life and held science as part of a rich intellectual, cultural and material life. His philosophical outlook integrated his science with and captured the new Victorian culture of construction and work, political, economic, artistic and engineering.     

社会信号处理与分析的基本框架：从社会传感网络到计算辩证解析方法

实时、可靠的社会信号，是实施有效的社会管理，特别是反馈闭环式的社会管理创新的基础．然而，相对于物理信号，社会信号的处理与分析有待系统化的研究与发展．随着社会新媒体和社会网络的蓬勃兴起和普及，这一问题变得更加迫切和急需．本文就社会信号与社会系统建模与管理，社会信号的刻画，社会传感网的构建．计算辩证推理和综合的人工社会、计算实验、平行执行（ACP）方法等展开讨论，希望在此基础上进一步开展研究与应用，最终建立面向社会信号之获取、分析、解析和应用的一般框架与方法体系．     

Characterization of a set of abdominal neuroendocrine cells that regulate stress physiology using colocalized diuretic peptides in <Emphasis Type="Italic">Drosophila</Emphasis>

Multiple neuropeptides are known to regulate water and ion balance in Drosophila melanogaster. Several of these peptides also have other functions in physiology and behavior. Examples are corticotropin-releasing factor-like diuretic hormone (diuretic hormone 44; DH44) and leucokinin (LK), both of which induce fluid secretion by Malpighian tubules (MTs), but also regulate stress responses, feeding, circadian activity and other behaviors. Here, we investigated the functional relations between the LK and DH44 signaling systems. DH44 and LK peptides are only colocalized in a set of abdominal neurosecretory cells (ABLKs). Targeted knockdown of each of these peptides in ABLKs leads to increased resistance to desiccation, starvation and ionic stress. Food ingestion is diminished by knockdown of DH44, but not LK, and water retention is increased by LK knockdown only. Thus, the two colocalized peptides display similar systemic actions, but differ with respect to regulation of feeding and body water retention. We also demonstrated that DH44 and LK have additive effects on fluid secretion by MTs. It is likely that the colocalized peptides are coreleased from ABLKs into the circulation and act on the tubules where they target different cell types and signaling systems to regulate diuresis and stress tolerance. Additional targets seem to be specific for each of the two peptides and subserve regulation of feeding and water retention. Our data suggest that the ABLKs and hormonal actions are sufficient for many of the known DH44 and LK functions, and that the remaining neurons in the CNS play other functional roles.     

Eph-dependent cell-cell adhesion and segregation in development and cancer

Numerous studies attest to essential roles for Eph receptors and their ephrin ligands in controlling cell positioning and tissue patterning during normal and oncogenic development. These studies suggest multiple, sometimes contradictory, functions of Eph-ephrin signalling, which under different conditions can promote either spreading and cell-cell adhesion or cytoskeletal collapse, cell rounding, de-adhesion and cell-cell segregation. A principle determinant of the balance between these two opposing responses is the degree of receptor/ligand clustering and activation. This equilibrium is likely altered in cancers and modulated by somatic mutations of key Eph family members that have emerged as candidate cancer markers in recent profiling studies. In addition, cross-talk amongst Ephs and with other signalling pathways significantly modulates cell-cell adhesion, both between and within Eph- and ephrin-expressing cell populations. This review summarises our current understanding of how Eph receptors control cell adhesion and morphology, and presents examples demonstrating the importance of these events in normal development and cancer.     

Interaction and cross-talk between non-coding RNAs

Non-coding RNA (ncRNA) has been shown to regulate diverse cellular processes and functions through controlling gene expression. Long non-coding RNAs (lncRNAs) act as a competing endogenous RNAs (ceRNAs) where microRNAs (miRNAs) and lncRNAs regulate each other through their biding sites. Interactions of miRNAs and lncRNAs have been reported to trigger decay of the targeted lncRNAs and have important roles in target gene regulation. These interactions form complicated and intertwined networks. Certain lncRNAs encode miRNAs and small nucleolar RNAs (snoRNAs), and may regulate expression of these small RNAs as precursors. SnoRNAs have also been reported to be precursors for PIWI-interacting RNAs (piRNAs) and thus may regulate the piRNAs as a precursor. These miRNAs and piRNAs target messenger RNAs (mRNAs) and regulate gene expression. In this review, we will present and discuss these interactions, cross-talk, and co-regulation of ncRNAs and gene regulation due to these interactions.     

Quantification of melanin in hepatic and cardiac lipofuscin

Summary Melanin pigment in liver and heart tissue, obtained at autopsy from patients, was isolated and quantified. The quantity of melanin extracted was directly proportional to lipofuscin granule counts. Infrared and electron spin resonance spectrographs of the isolated pigments from liver and heart showed absorption characteristics identical to those of known melanins. The pigment was absent in fetal and neonatal life, increased in brown atrophy of the heart and liver, and diminished in livers with fatty metamorphosis.Supported by USPHS, grant NS 07542, the St. Vincent Hospital Research Foundation and the Dermatopathology Foundation.