带有时变时滞的中立型随机系统的鲁棒镇定和H_∞控制

研究了带有时变时滞的中立型随机系统的鲁棒镇定和H∞控制问题.利用Lyapunov泛函方法和It o^公式,基于状态反馈控制器,以线性矩阵不等式(LMI)形式给出了闭环系统鲁棒镇定及H∞控制的新方法.最后,数值算例说明了该方法的有效性.     

Elaboration of an in vivo model, in half life size, for aeronautical purposes]

Toxic effects of combustion products originating from plane cabin constituents are studied, in vivo, in Rats. The model associates an important combustion room, and an experience room containing eight revolving cages for Rats; these cages allow a remote control of the movements of the Rats which can be electrically stimulated and ejected. Such a device permits to study the incapacitance, i.e. the inability to move. For the combustion of a seat, without ventilation, incapacitation appears in 2 to 6 min. Biochemical screening demonstrates on increase of pCO2, carboxyhemoglobin and glycemia and a decrease of pO2.     

Ecdysteroid hormone action

Several reviews devoted to various aspects of ecdysone research have been published during the last few years. Therefore, this article concentrates mainly on the considerable progress in ecdysone research observed recently, and will cover the results obtained during the last 2 years. The main emphasis is put on the molecular mode of ecdysteroid receptor-mediated hormone action. Two examples of interaction with other hormonal signalling pathways are described, namely crosstalk with juvenile hormone and insulin. Some selected, recently investigated examples of the multitude of hormonal responses are described. Finally, ecological aspects and some practical applications are discussed.     

Factor in human urine inhibiting lipid metabolism

Zusammenfassung Ein im Urin hungernder oder kachektischer Personen vorhandener Faktor, führt bei Mäusen nach s.c. Injektion im Blut zur Senkung des Ketonkörperspiegels. Der Leberfettgehalt wird herabgesetzt und eine schwache, jedoch regelmässig auftretende Erhöhung des Blutzuckerspiegels herbeigeführt. Bei der Ratte hemmt der Faktorin vitro die Freisetzung von Fettsäuren aus dem epididymalen Fettgewebe. Er beeinflusst möglicherweise den im Harn hungernder Menschen vorhandenen lipid mobilizing factor antagonistisch.     

A low level of extragalactic background light as revealed by gamma-rays from blazars

The diffuse extragalactic background light consists of the sum of the starlight emitted by galaxies through the history of the Universe, and it could also have an important contribution from the 'first stars', which may have formed before galaxy formation began. Direct measurements are difficult and not yet conclusive, owing to the large uncertainties caused by the bright foreground emission associated with zodiacal light. An alternative approach is to study the absorption features imprinted on the gamma-ray spectra of distant extragalactic objects by interactions of those photons with the background light photons. Here we report the discovery of gamma-ray emission from the blazars H 2356 - 309 and 1ES 1101 - 232, at redshifts z = 0.165 and z = 0.186, respectively. Their unexpectedly hard spectra provide an upper limit on the background light at optical/near-infrared wavelengths that appears to be very close to the lower limit given by the integrated light of resolved galaxies. The background flux at these wavelengths accordingly seems to be strongly dominated by the direct starlight from galaxies, thus excluding a large contribution from other sources-in particular from the first stars formed. This result also indicates that intergalactic space is more transparent to gamma-rays than previously thought.     

Metal Complexes:Novel Chiral Dopants with High Helical Twisting Power in Liquid Crystals

1 Introduction A particularly efficient and elegant route to chiral mesophases is based on the addition of small amounts of an enantiomerically pure dopant to a nematic phase so that the latter is converted into a cholesteric phase(See Fig.1).Fig.1 A nematic phase is converted into a cholesteric phase Fig.2 Bis-chelated imine-alkoxy-titanium complexes2 ExperimetalBis-chelated imine-alkoxy-titanium complexes like 1 and 2 (Fig.2) have been synthesizedstarting from triphenyl-substituted aminoethanols, T...     

Weiteres zum Lichtsinn augenloser Muscheln

Summary The cycless musselsAnodonta cygnea andPseudanodonta complanata do not show any phototaxis. In the Zweilichterversuch (two-light-experiment) they react to the decrease of light intensity. If light is increasing, the mussels will not react; if put in the shade, they immediately do so. If the shadow is moved, the mussels even react when the intensity of light decreases much less, which demonstrates the importance of motion. From this it follows that the reception of motion may be considered as possible where there is light sensitiveness of the skin, and where the experiment connects motion with shading.     

The effect of fasting,refeeding and meal eating on the ribonucleic acid content of adipose tissue in the rat

Zusammenfassung Durch experimentellen Hunger (48 bis 72 h) kommt es bei Ratten zu einer RNS-Minderung im mesentherialen, epididymalen und retroperitonealen Fettgewebe. Normale Fütterung oder Adaptation an beschränkte Fütterungsdauer (2 h pro Tag) führen zu einer Erhöhung des RNS-Gehaltes über die Normalwerte.