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41.
Previous studies have described a pattern of complex behavior that occurs in the marine mollusc Aplysia during egg laying. Egg laying and the behavior are initiated by a burst of impulse activity in the neuroendocrine bag cells of the abdominal ganglion or by injection of bag cell extract. To more precisely identify the factors responsible for inducing the behavior we injected animals with egg laying hormone (ELH), one of the neuropeptides secreted by the bag cells. We found that ELH causes a behavior pattern similar to what occurs during spontaneous egg laying. This includes a temporal pattern of head movements consisting of waves and undulations, followed near the beginning of egg deposition by a transition to head weaves and tamps and inhibition of locomotion. There was also a small decrease in respiratory pumping. Except for respiratory pumping, a similar pattern occurred in a second group of animals injected with atrial gland homogenate, which is presumed to induce bag cell activity, but not in controls. These results further implicate ELH in regulation of the behavior. We discuss possible sites of action of ELH and the neural mechanisms by which the behavior is controlled.  相似文献   
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Developing and selecting high quality software applications are fundamental. It is important that the software applications can be evaluated for every relevant quality characteristic using validated metrics. Software engineers have been putting forward hundreds of quality metrics for software programs, disregarding databases. However, software data aspects are important because the size of data and their system nature contribute to many aspects of a systems quality. In this paper, we proposed some internal metrics to measure relational databases which influence its complexity. Considering the main characteristics of a relational table, we can propose the number of attributes (NA) of a table, the depth of the referential tree (DRT) of a table, and the referential degree (RD) of a table. These measures are characterized using measurement theory, particularly the formal framework proposed by Zuse. As many important issues faced by the software engineering community can only be addressed by experimentation, an experiment has been carried out in order to validate these metrics.  相似文献   
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The CERN Large Hadron Collider (LHC) has 54 km of ultra-high vacuum (UHV) beam chambers out of which about 90% are at cryogenic temperature (1.9 K) and the rest at room temperature. During operation, the residual gas density in the beam pipes is dominated by beam induced effect such ion, electron and photon-stimulated gas desorption. Therefore, the computation of gas density profile is of great importance to confirm the vacuum stability, and to estimate the beam lifetime. Moreover, the gas density profiles are essential to determine the machine induced background in the experimental areas, and to define the pressure profile in the cryogenic sectors where there is no vacuum instrumentation available.In this paper, the vacuum stability is studied for a newly proposed upgrade of the vacuum chamber at the ATLAS interaction point, using the vacuum stability code called VASCO. The residual gas density profile along the ATLAS vacuum chambers and the effects of photon and electron flux hitting the vacuum chamber walls are presented and analysed.  相似文献   
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The changes that occur, especially in the dietary fibre, during processing of white asparagus have been studied. Processing consists of submitting the vegetable to a treatment with hot water (96 °C), for 4 min (blanching) and subsequently immersing it in a sodium chloride solution (brining). Finally, the asparagus is sealed and sterilised at 115–116 °C. The study was performed on the whole asparagus and also, separately, on the apex and stem. As a result of processing there was an increase in the moisture and protein contents and a decrease in those of uronic acids and free sugars, saccharose disappearing entirely. It is concluded that the most important changes taking place in the asparagus fibre fraction during thermal treatments are the slight decrease of lignin and uronic acids, the slight increase in proteins and an important decrease in hemicelluloses.
Effekt der Verarbeitung auf den Gehalt an Ballaststoffen bei Spargel
Zusammenfassung Vierminütiges Blanchieren bei 96 °C, Einlegen in eine Salzlake und Sterilisieren bei 115–116 °C wurde bei ganzem weißen Spargel sowie getrennt bei Köpfen und Stangen untersucht. Durch den Prozeß steigt der Gehalt an Wasser und Eiweiß, während Uronsäuren und freie Zucker verlorengehen. Auffallend sind die Veränderungen der Ballaststofffraktion, leichten Verlusten bei Lignin und Uronsäuren und einer leichten Zunahme der Proteine steht ein massiver Verlust an Hemicellulosen gegenüber.
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Sustainable development is a type of development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Sustainability has recently become more and more important for businesses. This has led to what is known as Green BPM (Green business process management), in which sustainability is considered to be a business objective. The objective of this work was to carry out a systematic literature review in order to evaluate how the subject of Green BPM has evolved and how the term “Green BPM” has been conceptualised so as to propose a new definition compiled from those previously formulated; identify the impact of the incorporation of Green aspects into the BPM life cycle stages; and discover the impact of Green BPM research efforts by means of the PDCA (plan‐do‐check‐act) model, thus identifying (1) the goals that have been proposed when Green initiatives are carried out in BPM, (2) the context in which this has been applied, and (3) the performance indicators considered. Finally, we propose a new characteristic, Process Greenability, together with its subcharacteristics, in addition to identifying the relationship between these subcharacteristics and the indicators identified to make them measurable.  相似文献   
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Triggering of HLA class II antigens by the anti-HLA-DR monoclonal antibody (mAb) L243 significantly (P < 0.05) and differentially enhanced the release of tumor necrosis factor alpha (TNF-alpha) by the non-Hodgkin's lymphoma cells Ri-I, Ci-I, and Sc-I, which are at a distinct stage of B-cell differentiation, and by the more mature Burkitt lymphoma cell Raji; in contrast, it did not induce TNF-alpha release by the pre-B leukemia cells Nalm-6 and BV173. TNF-alpha release peaked at 24 h and decreased thereafter, and it was dose dependent and preceded by an increase of TNF-alpha mRNA detectable after 3 h of stimulation with mAb L243. Secreted TNF-alpha mediated the enhancement of nuclear factor kappa B (NF-kappa B) and activator protein-1 (AP-1) binding activity; in fact, the triggering of HLA-DR antigens in the presence of antihuman TNF-alpha-neutralizing antibodies did not upregulate NF-kappa B and AP-1. In contrast, released TNF-alpha was not responsible for the homotypic aggregation of Ri-I, Ci-I, Sc-I, and Raji cells induced by mAb L243, and it did not affect the proliferation of B cells investigated. Altogether, our data demonstrate that: (a) the ability of B cells to release TNF-alpha after triggering of HLA-DR antigens depends on their stage of differentiation; (b) levels of released TNF-alpha seem to correlate with the stage of B-cell maturation but do not correlate with the amounts of cell surface HLA-DR antigens; (c) secreted TNF-alpha regulates the levels of expression of NF-kappa B and AP-1 by an autocrine loop; and (d) intracellular signals mediating TNF-alpha release by B cells are distinct from those regulating homotypic aggregation and proliferation.  相似文献   
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Echo is a twenty-minute interactive multi-screen research drama which addresses the question of how we can overcome narcissism in a hypermediated age. This article outlines the search for the appropriate form for the final art work using the concept of remediation to explore how the piece developed for multi-platform distribution and exhibition, as an online screen media drama and as a work for gallery installation. In outlining the process of production, the article explores the poetics of multi-screen immersive gallery drama and split-screen drama, and discusses the new and remediated possibilities for these forms.  相似文献   
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