A comparison between the free grafting of sliced and intact muscles in the rat-1.

Transverse slicing is a new technique whereby a mammalian muscle can be freely grafted with success. This method eliminates contamination of the early graft by surviving muscle fibres and allows one to measure the development of contractile properties on a uniform population of regenerating muscle fibres.?IOAuthor     

In vitro study of cellular affinity to various protein supports suited for vascular prosthesis]

We compare the affinity of different cellular samples with regard to variosu artificial materials by organotypic culture method. We use a technique which allows at once, to obtain the cells and to measure their migration on the artificial surface. The results show a high variation of the cellular affinity from one sample to another.     

A comparison between the free grafting of sliced and intact muscles in the rat

Summary Transverse slicing is a new technique whereby a mammalian muscle can be freely grafted with success. This method eliminates contamination of the early graft by surviving muscle fibres and allows one to measure the development of contractile properties on a uniform population of regenerating muscle fibres.Supported in part by a grant from the Muscular Dystrophy Associations of America, Inc.Part of this research was carried out while on a scientific exchange between the US and Czechoslovak Academies of Sciences.     

Patch clamp technique and biophysical study of membrane channels

The present work describes the patch clamp technique, which first allowed the recording of single channel currents in biological membranes. In particular, it describes procedures for preparation and applications of the four different patch clamp configurations. Briefly, the cell-attached configuration is widely used for investigating channel modulation by transmitters acting via second messengers. The cell-free configurations (inside-out and outside-out), complementary to one another with respect to the orientation of the membrane surface, are particularly indicated for the study of the biophysics (kinetics, conductivity, selectivity, mechanism of permeation and block) of ionic channels. Finally, the whole-cell configuration which, because of the remarkable feature that it allows voltage clamp of very small cells, has given access to a number of physiologically important preparations never studied before.     

Patch clamp technique and biophysical study of membrane channels

Summary The present work describes the patch clamp technique, which first allowed the recording of single channel currents in biological membranes. In particular, it describes procedures for preparation and applications of the four different patch clamp configurations. Briefly, the cell-attached configuration is widely used for investigating channel modulation by transmitters acting via second messengers. The cell-free configurations (inside-out and outside-out), complementary to one another with respect to the orientation of the membrane surface, are particularly indicated for the study of the biophysics (kinetics, conductivity, selectivity, mechanism of permeation and block) of ionic channels. Finally, the whole-cell configuration which, because of the remarkable feature that it allows voltage clamp of very small cells, has given access to a number of physiologically important preparations never studied before.     

层叠式锂离子电池展向温度分布的分析解及基于分析解的热设计优化

大型锂离子动力电池的热相关问题是限制其在电动汽车上大规模应用的主要问题之一.单体电池的热模型是进行电池热设计、改善电池热特性的重要工具.根据热模型的求解方法,可分为数值解和分析解两类.在现有文献的研究中,数值解占据了主要地位.但是,分析解因具有计算量小、可实现设计变量的全局优化等优点,在电池热设计和电池组热管理系统中可发挥重要作用.例如,在电池热设计中,分析解可全面考察多个设计参数连续变化下对电池热特性的影响,以进行多设计参数下的全局优化.本文首先对一款大型层叠式锂离子电池进行了数值热模拟和实验验证,数值热模拟的结果与多枚热电偶的实验测量结果吻合良好;然后,基于数值热模拟的结果提取了层叠式电池温度分布和产热率分布的主要特点,进而假设温度呈展向平面分布、产热率均匀分布;针对简化后的电池热问题,利用双重积分变换方法提出了分析解;最后,使用分析解开展了电池的热设计优化工作,讨论了不同电芯尺寸和极耳布置方案下的电池热特性.     

Structures of 9 oligosaccharides and glycopeptides containing large amounts of fucose excreted in the urine of 2 patients with fucosidosis]

Binding of corticosterone and aldosterone to plasma proteins of the edible Frog was studied by equilibrium dialysis technique. A high-affinity, transcortin-like, corticosterone binding system has been demonstrated, but, in vivo, the unbound fraction of this corticosteroid is higher that the bound one. Hypophysectomy and thyroidectomy do not change corticosteroids binding parameters which are modified by a variation of temperature.     

Anti-elastase of human pancreas: preparation and biological interest

The present paper deals with the use of a new technique in type II human pancreatic elastase studies based on the use of a reversible immune-adsorbent which provides a unique specificity. According to the type of ligand linked on activated Sepharose, the elastase or its antibody in Rabbit could be obtained, in very pure form, in a one step process. The anti-human pancreatic elastase II, which specifically inhibits the enzyme, may be used in therapy whenever the elastase-inhibitor system becomes unbalanced.     

Specific radioimmunoprecipitation of histone H2A antigens by protein A conjugated sepharose

A modified radioimmunoprecipitation technique is described which allows the specific detection of histone H2A antigens. The technique circumvents unspecific binding of histones to the bacterial adsorbent.     

Ultrastructural identification of the nucleolus organizer by the silver staining technic]

The nucleolus organizer regions can be selectively stained in metaphase chromosome preparations by the Goodpasture and Bloom's technique which was adapted to electron microscopy analysis of cells during interphase. Using this technique, a selective accumulation of silver grains was observed over nucleolus light areas. This selective accumulation allows the identification of the interphase fibrillar centers as the nucleolus organizer regions. Ultrastructural relationships between fibrillar centers and dense fibrillar component are discussed.     

Specific radioimmunoprecipitation of histone H2A antigens by protein A conjugated sepharose

Summary A modified radioimmunoprecipitation technique is described which allows the specific detection of histone H2A antigens. The technique circumvents unspecific binding of histones to the bacterial adsorbent.     

Interpretation of the gingival inflammatory infiltrate]

The investigation of tooth eruption in dermoid cysts of the ovary allows one to observe in the chorion at the level of the epithelial attachment, an anatomical component that seems to correspond to a local system of defense. Up until now this has been considered to be a secondary inflammatory response resulting from the bacterial or mechanical assault. This component is found to form when the tooth erupts and constitutes an important element in the physico-pathogical process and of the immune response of the dental organ.     

Newton's Contribution to the Science of Heat

The contents of Scala Graduum Caloris are described, supplemented by unpublished material. Both temperature measurements by his linseed oil thermometer and those based upon his law of cooling are shown to be reasonably accurate to 300°C, but above that value they are much too low. The apparent agreement and the deviation are explained by the differences between the assumptions that Newton made in deriving his law of cooling and the conditions in which he used it. Newton's attempts to link terrestrial and celestial science in applications in the Principia are shown to fail from his confounding the concepts of temperature, heat and radiant intensity and his ignorance of most factors affecting the temperature rise of irradiated materials. Other comments on varied aspects of heat, mainly published in the Queries, are set out and analysed. His originality is assessed.     

Perifused alveolar macrophages. A technique to study the effects of toxicants on prostaglandin release

Summary A technique was developed for perfusing free airway cells (FAC) obtained by guinea-pig bronchoalveolar lavage. 10×10⁶ FAC (mostly macrophages) were placed on the filter of a Nuclepore chamber perfused with Tyrode's solution or with Eagle's Minimal Essential Medium (MEM); the effluent was collected at intervals and the release of prostaglandin E₂ by the perifused cells was used as an index of the inflammatory reaction to toxicants. Zymosan, asbestos fibers and soluble toxic agents stimulated the synthesis of prostaglandins while indomethacin abolished it. Our technique of FAC perifusion allows the sequential study of biochemical events involved in macrophage defense mechanisms as well as providing a simple test for the evaluation of various toxicants.Acknowledgments. The authors thank the Conseil de la Recherche en Santé du Québec and the Centre de recherches médicales de l'Université de Sherbrooke for their generous support, and Miss Solange Cloutier for skilful technical assistance.     

A method for determining cross-measurements of motor neurons

Summary This new triangulation technique allows the investigator to make cross-measurements of individual cells quickly and easily with a high degree of accuracy and reliability.     

Ruling Engines,Diffraction Gratings and Wavelength Measurements before the Rowland Era

Diffraction gratings have contributed enormously to modern science. Although some historians have written about them, there is much more to be brought to light. This paper discusses their development and use in the period up to about 1880 before Rowland began to produce them. Rittenhouse described the action of a diffraction grating in 1786, but no explanation was possible until the wave theory of light was developed. Fraunhofer discovered the dark lines in the solar spectrum in 1814, and then investigated diffraction, producing the first ruled gratings, making detailed measurements and calculating the wavelengths of prominent spectral lines. After Bunsen and Kirchhoff showed the association between spectral lines and chemical elements there was an upsurge of interest in measuring wavelengths. The gratings used in this work almost all came from one source, a relatively unknown instrument maker called Nobert, who made them by an extremely laborious process using a machine he had built himself. The most significant wavelength measurements were made by Ångström, but Mascart, Van der Willigen, Stefan, Ditscheiner and Cornu also did important work. Nobert gratings were investigated by Quincke, copied photographically by Rayleigh, and were known and discussed in the USA. Nobert's work helped to advance spectroscopy much more than has been acknowledged.     

Idealizations and analogies: Explaining critical phenomena

The “universality” of critical phenomena is much discussed in philosophy of scientific explanation, idealizations and philosophy of physics. Lange and Reutlinger recently opposed Batterman concerning the role of some deliberate distortions in unifying a large class of phenomena, regardless of microscopic constitution. They argue for an essential explanatory role for “commonalities” rather than that of idealizations. Building on Batterman's insight, this article aims to show that assessing the differences between the universality of critical phenomena and two paradigmatic cases of “commonality strategy”—the ideal gas model and the harmonic oscillator model—is necessary to avoid the objections raised by Lange and Reutlinger. Taking these universal explanations as benchmarks for critical phenomena reveals the importance of the different roles played by analogies underlying the use of the models. A special combination of physical and formal analogies allows one to explain the epistemic autonomy of the universality of critical phenomena through an explicative loop.     

Understanding of the influence of process parameters on the heat transfer behavior at the metal/die interface in high pressure die casting process

The current paper focuses on the influence of the process parameters on the peak values of the interfacial heat transfer coefficient(IHTC)at metal/die interface during high pressure die casting(HPDC)process.A"step shape"casting and AM50 alloy were used during the experiment.The IHTC was determined by solving the inverse thermal problem based on the measured temperature inside the die.Results show that the initial die surface temperature(IDST,TDI)has a dominant influence while the casting pressure and fast shot velocity have a secondary influence on the IHTC peak values.By curve fitting,it was found that the IHTC peak value(hmax)changes as a function of the IDST in a manner of hmax=e αTγ DI .Such relationship between the IHTC peak value and the IDST can also be found when the casting alloy is ADC12,indicating that this phenomenon is a common characteristic in the HPDC process.     

Le rôle de la prospection sous-marine autonome dans les recherches de biologie marine et d'océanographie biologique

Summary At the present time the autonomous exploration of the sea may be divided into three main fields: airScuba down to 60 m; diving saucers down to 1200 m; bathyscaph down to the greatest depths of the ocean. In the near future, theScuba with special gas mixtures, excluding nitrogen, and the underwater permanent laboratories, will open a new field for biological investigations; progress in metallurgy may also allow diving with engines, without a floating tank, down to 2000 m.The ability of the deep-sea vehicles to stop and remain at a definite depth below the surface needs further research.TheScuba is interesting for investigating the biotopes where the usual devices cannot be used from a surface vessel, for instance in submarine caves. Very special biocoenoses have been found in the totally dark parts of these caves with impoverished stocks and sometimes relict species; the sampling may be perfect both on soft and hard bottoms. With the deep-sea vehicles, investigations may be carried out on the behaviour and distribution of the bottom epifauna. The bathyscaph also allows a general view of the vertical distribution of plankton much better than using plankton samplers, because the plankton nets or pumps are always working on a discontinuous scale. Unfortunately the sampling is much more difficult, especially as far as the plankton is concerned. It is necessary that the engineers pay more attention to the biological devices; very good data have been obtained for temperature, pressure, sound-velocity, etc., but in many instances the biologist diving with a deep-sea vehicle cannot do more than look at the animals and take photographs.