板材液压拉深试验装置开发

开发了一种用于板材液压拉深成形性能研究的试验装置，包括拉深模具及液压控制系统。该装置不需要复杂的外部供液系统、压边系统及凸模导向系统，在普通的单动压力机上就能实现对不同材料及尺寸板材的普通拉深和液压拉深试验。初步的试验表明，该装置结构简单、操作方便、工作可靠，满足板材液压拉深试验要求，能够有效的改善板材的成形性能。     

Beitrag zur Ätiologie der Hexenbesenkrankheit der KakteeOpuntia tuna (=tuna monstrosa)

Summary Mycoplasma-like bodies, as well as virus-like particles, were observed in phloem elements ofOpuntia tuna monstrosa. The mycoplasma-like bodies, but not the virus-like particles, disappeared in tetracycline hydrochloride treated plants, which indicated a mycoplasma etiology of the witches' broom disease ofOpuntia tuna.

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This investigation was supported, in part, by a grant from the National Science Foundation No. GB-11861, Washington, D.C.     

Voltage-gated sodium channel-associated proteins and alternative mechanisms of inactivation and block

Voltage-gated sodium channels mediate inward current of action potentials upon membrane depolarization of excitable cells. The initial transient sodium current is restricted to milliseconds through three distinct channel-inactivating and blocking mechanisms. All pore-forming alpha subunits of sodium channels possess structural elements mediating fast inactivation upon depolarization and recovery within milliseconds upon membrane repolarization. Accessory subunits modulate fast inactivation dynamics, but these proteins can also limit current by contributing distinct inactivation and blocking particles. A-type isoforms of fibroblast growth factor homologous factors (FHFs) bear a particle that induces long-term channel inactivation, while sodium channel subunit Navβ4 employs a blocking particle that rapidly dissociates upon membrane repolarization to generate resurgent current. Despite their different physiological functions, the FHF and Navβ4 particles have similarity in amino acid composition and mechanisms for docking within sodium channels. The three competing channel-inactivating and blocking processes functionally interact to regulate a neuron’s intrinsic excitability.     

The Loss of Coherence in Quantum Cosmology

I analyse two different methods for the retrieval of a classical notion of spacetime from the theory of quantum cosmology in terms of the different means they employ to bring about the necessary loss of coherence. One method employs a direct coarse graining of the appropriate phase space, whereas the other method is based on decohering the system by the interaction with an environment. Although these methods are equivalent on a phenomenological level, I argue that conceptually the decoherence approach is superior. The coarse graining approach construes the necessary loss of coherence in epistemic terms, whereas the method based on decohering the system by interaction with an environment provides a dynamical explanation for the emergence of classical notions of spacetime. On the latter account the emergence of classical behaviour is an objective property of the physical system under consideration, in contradistinction with the subjective coarse graining account of the retrieval of a classical spacetime in terms of measurements made by an observer.     

Suppression of annual plasma testosterone and thyroxine cycles in the edible dormouseGlis glis under constant photoperiod at 24°C

Summary Exposure of male ebible dormice all year round to an unwarying photoperiod and warm temperature disrupted their biological cycles; hibernation was almost completely suppressed, and short lived infradian cycles of body weight, and of plasma testosterone and thyroxine were measured instead of the normal annual patten.     

Suppression of annual plasma testosterone and thyroxine cycles in the edible dormouse Glis glis under constant photoperiod at 24 degrees C

Exposure of male edible dormice all year round to an unvarying photoperiod and warm temperature disrupted their biological cycles; hibernation was almost completely suppressed, and short lived infradian cycles of body weight, and of plasma testosterone and thyroxine were measured instead of the normal annual pattern.     

Early skin responses of hibernating and nonhibernating ground squirrels to topical applications of DMBA

Skin patches on hibernating and nonhibernating ground squirrels were treated with multiple topical applications of the carcinogen 7,12-dimethylbenza(a)anthracene. Nonhibernators showed blistering, peeling, drying, hair loss, increased vascularization and hyperpigmentation in proportion to DMBA concentration. The latter was apparently due to a) an increased number of dermal and epidermal melanocytes and b) the appearance of melanocytes with large coarse cytoplasmic granules. Notably, hibernators remained free of gross skin changes and were histologically similar to untreated controls.     

Binding of ferritin-lectin conjugates to C-type virus in intact cells.

Ferritin-Ricin II and Ferritin-Concanavalin A bound to budding as well as mature C-type viral particles. No differencies in binding between the viral coat and adjacent plasma membrane were detected with either lectin conjugate. Aggregation of viral particles by lectin conjugates was observed, and linking of virus to the plasma membrane resulted in phagocytosis of viral particles.     

Detailed analysis of the plasma extracellular vesicle proteome after separation from lipoproteins

The isolation of extracellular vesicles (EVs) from blood is of great importance to understand the biological role of circulating EVs and to develop EVs as biomarkers of disease. Due to the concurrent presence of lipoprotein particles, however, blood is one of the most difficult body fluids to isolate EVs from. The aim of this study was to develop a robust method to isolate and characterise EVs from blood with minimal contamination by plasma proteins and lipoprotein particles. Plasma and serum were collected from healthy subjects, and EVs were isolated by size-exclusion chromatography (SEC), with most particles being present in fractions 8–12, while the bulk of the plasma proteins was present in fractions 11–28. Vesicle markers peaked in fractions 7–11; however, the same fractions also contained lipoprotein particles. The purity of EVs was improved by combining a density cushion with SEC to further separate lipoprotein particles from the vesicles, which reduced the contamination of lipoprotein particles by 100-fold. Using this novel isolation procedure, a total of 1187 proteins were identified in plasma EVs by mass spectrometry, of which several proteins are known as EV-associated proteins but have hitherto not been identified in the previous proteomic studies of plasma EVs. This study shows that SEC alone is unable to completely separate plasma EVs from lipoprotein particles. However, combining SEC with a density cushion significantly improved the separation of EVs from lipoproteins and allowed for a detailed analysis of the proteome of plasma EVs, thus making blood a viable source for EV biomarker discovery.     

Dielectric tunable properties of BaTi_4O_9-doped Ba_(0.6)Sr_(0.4)TiO_3 microwave composite ceramics

BaTi4O9-doped Ba0.6Sr0.4TiO3(BST) composite ceramics were prepared by the conventional solid-state reaction and their structure,dielectric nonlinear characteristics and microwave dielectric properties were investigated.The secondary phase of the orthorhombic structure Ba4Ti13O30 is formed among BST composite ceramics with the increase of BaTi4O9.At the same time,a duplex or bimodal grains size distribution shows fine grains in a coarse grain matrix.The degree of frequency dispersion of dielectric permittivity below Tm is increased initially and then decreased with respect to BaTi4O9.As the BaTi4O9 content increases,the tunability of composite ceramics decreases,while the Q value increases.Interestingly,70 wt%BaTi4O9-doped BST has a tunability～4.0%(under 30 kV/cm biasing) versus a permittivity～68 and quality factor ～134.1(at～3.2 GHz) .     

Relationship between A-type and C-type particles in Ehrlich ascites tumor cells.

Intracisternal and intracytoplasmic A-type particles were discovered in Ehrlich ascites tumor cells. In addition, 'mature' and 'immature' C-type particles were also seen in the intercellular space. It is believed that A particles may represent a precursor or a formative stage of the C particles.     

Thermoperiodic information and the induction of diapause in Pieris brassicae L]

When exposed their whole larval life to a 24 h. thermoperiodic cycle in constant darkness, individuals of Pieris brassicae L. give diapausing or non-diapausing pupae according to the length of the cold and warm sequences. The curve of thermoperiodic induction is similar to the photoperiodic curve.     

Light metal compound casting

Compound castingsimplifies joining processes by directly casting a metallic melt onto a solid metal substrate.A continuously metallurgic transition is very important for industrial applications,such as joint structures of spaceframe constructions in transport industry.In this project,compound castingof light metals is investigated,aiming at weight-saving.The substrate used is a wrought aluminium alloy of type AA5xxx,containing magnesium as main alloying element. The melts are aluminium alloys,containing var...     

Presence of oncornavirus-like particles in the P388 murine leukemic cell line

A culture of P388 murine lymphoblastoid cells has been shown to contain type C oncornavirus-like particles budding at the plasma membrane. Occasionally intracytoplasmic type A and immature type B particles were also observed by electron microscope techniques. The discovery of oncornavirus-like particles in the P388 cell line increases the utility of this neoplastic system for detecting potential antineoplastic agents.     

Application of immunoelectron microscopy to the detection of viruses in a water medium]

Adenoviruses were immersed in demineralyzed and deionized water for 5 days. The water was subsequently analyzed by Immuno-Electron-Microscopy for detection of viral particles. An attempt of quantation was also made on control, untreated particles. Viruses dispersed in water can be detected by the technique employed but quantitation is limited by the heterogeneous dispersion of the particles on the grids.     

改善复杂形状的热成形先进高强钢汽车结构件成形性的工艺开发和机理分析

针对具有形状要求的先进高强钢(AHSS)汽车结构件热成形时经常发生破裂现象,从其各处分布的不同应力方式对样件微观结构、厚度分布和力学性能影响作用存在差异的角度分析,首次利用高速加热炉、急冷处理室和带有冷却水道模具的一体化实验设备,通过在冲压前设计急冷处理新方法,即由现有工艺的奥氏体化后直接冲压成形,转变成先经急冷处理,然后到700°C左右成形,其目的是:使得样件上以拉应力为主的加载区,因具有较好硬化指数n值而获得较好成形性;以压应力为主的某些抑制马氏体相变区域,因提前的急冷处理而在微观奥氏体母相中增加马氏体新相形核的几率,获得致密的组织结构,以改善强韧性.实验证明,通过冲压前的急冷处理,样件更为完整,未出现开裂现象;微观具有明显细化的马氏体排列形态;宏观硬度分布均匀,且都在460 Hv以上,能够满足高强度、高韧性的性能要求.从而,验证了该急冷方法的科学有效,并突破了国内现有热成形AHSS易开裂的瓶颈问题,为建立我国自有知识产权、复杂形状的热成形AHSS结构件生产工艺路线提供了依据.     

Intracisternal A type particles of the extraocular muscle of hereditary muscular dystrophy mouse.

Intracisternal A type virus (IA) particles were observed in the extraocular muscle fiber of hereditary muscular dystroph mouse. The particles appeared approximately 65-75 mmu in diameter, with electron lucent cores.     

Binding of ferritin-lectin conjugates to C-type virus in intact cells

Summary Ferritin-Ricin II and Ferritin-Concanavalin A bound to budding as well as mature C-type viral particles. No differencies in binding between the viral coat and adjacent plasma membrane were detected with either lectin conjugate. Aggregation of viral particles by lectin conjugates was observed, and linking of virus to the plasma membrane resulted in phagocytosis of viral particles.Acknowledgment. The authors thank Phyllis Johnson for her excellent technical assistance. This work was supported by NIH grant CA 15044-03 and NS 06208. LM is the recipient of an NINDS Research Career Development Award 1 KO4-NS 00101.     

Accumulation of 2-micron latex particles in mouse Peyer's patches during chronic latex feeding

2-micron latex particles accumulated in macrophages in intestinal Peyer's patches of mice given latex suspensions as drinking fluid for 2 months. The number of particles accumulating was a direct (but nonlinear) function of the number ingested. Some of the latex particles were still present in Peyer's patches 6 weeks after the cessation of latex feeding.     

Early skin responses of hibernating and nonhibernating ground squirrels to topical applications of DMBA

Summary Skin patches on hibernating and nonhibernating ground squirrels were treated with multiple topical applications of the carcinogen 7,12-dimethylbenza(a)anthracene. Nonhibernators showed blistering, peeling, drying, hair loss, increased vascularization and hyperpigmentation in proportion to DMBA concentration. The latter was apparently due to a) an increased number of dermal and epidermal melanocytes and b) the appearance of melanocytes with large coarse cytoplasmic granules. Notably, hibernators remained free of gross skin changes and were histologically similar to untreated controls. Acknowledgments. This study was supported by Biomedical Research Support Grant No. 5-SO7-RR05413-20. I wish to thank Mrs Mary Gregory for her help with the silver-methenamine borate technique, Mr Albert Geiser for the photomicrographs and Dr George B. Kemper for his contributions in general.