In the intention to offer agricultural information which can meet user demand and economic requirements, The German Centre for Agricultural Information and Documentation (ZADI) is developing a new ...literature and factual data management system (LIMAS). Using LIMAS the EDP-aided processes of database production will be put on a new basis. The new implementations originate from the rightsizing of the software and hardware environment. A client-server based PC-network will be used instead of the mainframe environment. The cooperating documentation centres will develop from isolated input suppliers into a computing workgroup. The developing tools are characterized by modern techniques as CASE-tools, modern database architecture, and graphical user interface. In addition to more efficient production processes, LIMAS includes a variety of standardized database analyses. Scientometric and bibliographic analyses and graphics will be implemented. An overview of the database contents is available at any time. The user will control the system with standardized control elements. The knowledge of a retrieval languages will not be required
Acute interruption of circulation in the distal fingers can be both expression of an embolic event as well as the first manifestation of a vasculitis or collagenosis. The search for its cause is ...frequently difficult. In many cases a specialized analysis of the coagulation system as well as diagnostics such as ultrasound scan of the heart or a systematic antibody scanning do not reveal the origin of an embolus or the underlying disorder. On the basis of a case-report we would like to focus on a possible context between an infection of Borrelias stage III and consecutive deterioration of peripheral arterial perfusion in the fingers. Besides Jo-1- and positive sceleton-muscle-antibodies there were no serological and clinical indications for an autoimmune disease. It was possible to avoid acral necrosis by means of an antibiotic, immunosuppressive and rheological therapeutic concept. We recommend to control the borellia-antibody-level in cases of obscure threatening peripheral necrosis caused by arterial perfusion stop.
The rationale is given of how the gross physical features of the circulation and the stratification of the North Sea have been aggregated for inclusion in the ecosystem box model ERSEM. As the ...ecosystem dynamics are to a large extent determined by small-scale physical events, the ecosystem model is forced with the circulation of a specific year rather than using the long-term mean circulation field. Especially the vertical exchange processes have been explicitly included, because the primary production strongly depends on them. Simulations with a general circulation model (GCM), forced by three-hourly meteorological fields, have been utilized to derive daily horizontal transport values driving ERSEM on boxes of sizes of a few 100 km. The daily vertical transports across a fixed 30-m interface provide the necessary short-term event character of the vertical exchange.
For the years 1988 and 1989 the properties of the hydrodynamic flow fields are presented in terms of trajectories of the flow, thermocline depths, of water budgets, flushing times and diffusion rates. The results of the standard simulation with ERSEM show that the daily variability of the circulation, being smoothed by the box integration procedure, is transferred to the chemical and biological state variables to a very limited degree only.
Agricultural information and documentation (I&D) centres have at their disposal a large amount of expert knowledge and experience with databases, documentation, and information resulting from their ...classical subject fields. The transformation of this into the requirements of the new media will result in modern end-user oriented information systems like the German Agricultural Information Network (Deutsches Agrarinformationsnetz, DAINet, http://www.dainet.de). This demonstration shows how the transformation of existing knowledge in combination with modern web and database technology has been used to create the world's largest agricultural search catalogue on the web. The classification systems are explained as well as the contents of the metadata formats. Presently, DAINet links and describes more than 7,500 agriculture-related information sources worldwide and about 800 institutional web sites. Over 150,000 page requests per month from all over the world illustrate the need for the DAINet search catalogue. The conclusions give a perspective of future developments.
Reversal in the trend toward convergence of black and white fertility rates in the United States between 1940 and 1970 has given rise to the theory of independent effect of minority racial status. ...The 1970 Public Use Sample is used in this study to extract data on a 1/1000 sample of all black and white women (excluding Spanish Americans) ages 15 to 59 in order to analyze relationships between fertility and other census variables. The results tend to support the theory of independent effect of minority racial status on fertility. The relationship is more pronounced for women under 35 than for women 40 and over. Distinctive patterns emerge by race and age cohorts.
Mit einem Stift‐Scheibe Tribometer, bei dem eine Graugussscheibe gegen einen verchromten Stahlstift rotiert, wurde kontinuierlich und mit hoher Auflösung Reibung und Verschleiß gemessen. Durch ...Variation von Normalkraft und Gleitgeschwindigkeit wurden Proben generiert, die sich deutlich in der Höhe der dissipierten Energie unterschieden. Diese Proben wurden vor und nach der tribologischen Belastung strukturell durch eine Feinfokus‐Ionenstrahlanlage (Focused Ion Beam ‐ FIB) untersucht. Es stellte sich heraus, dass im oberflächennahen Bereich durch tribologische Wechselwirkung der Korndurchmesser drastisch abnimmt. Parallel dazu kommt es zum Eintrag von Fremdatomen aus dem Schmierstoff und Umgebung, was durch Augerelektronenspektroskopie nachgewiesen wurde. Mittels Röntgenbeugungsverfahren wurde der mechanische Spannungszustand analysiert, und durch Nanoindentation konnten die mechanischen Eigenschaften im oberflächennahen Bereich bestimmt werden. Tribologisch optimal eingelaufenes Material zeigte im oberflächennahen Bereich nanokristalline Struktur, die erheblich verringerten Reibungswiderstand besaß.
Structure, Hardness and Stress State Analysis on Metal‐Metal Tribocontacts with Oil Lubrication
A common pin‐on‐disk tribometer was used to generate the samples. In all experiments a chromium‐plated steel pin was run against a gray cast iron disk with lubrication. Wear was measured with the radionuclide technique allowing online tests to monitor the wear rate with a resolution of a few nanometers per hour. Due to variation of normal force and sliding velocity the samples were generated, to obtain different degrees of tribological interaction. Both the surface of the involved materials as well as their volumes experience modifications with respect to morphology, crystalline arrangement and chemical bonds. The depth of tribological interaction at given conditions has an extension of a micrometer or less. To probe these thin modified zones Focussed Ion Beam, Auger‐Spectroscopy, synchrotron‐based X‐ray diffraction and nanoindentation were applied. The best tribological characteristics, low wear rate and low friction coefficient showed a sample with a nanocrystalline structure in near surface region.
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