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921.
Adeel Nasir Peter Rolf Richter Aude Le Bail Viktor Daiker Julia Stoltze Binod Prasad Sebastian Michael Strauch Michael Lebert 《International journal of molecular sciences》2022,23(5)
Euglena gracilis is a photosynthetic flagellate. To acquire a suitable position in its surrounding aquatic environment, it exploits light and gravity primarily as environmental cues. Several physiological studies have indicated a fine-tuned relationship between gravity sensing (gravitaxis) and light sensing in E. gracilis. However, the underlying molecular mechanism is largely unknown. The photoreceptor photoactivated adenylyl cyclase (PAC) has been studied for over a decade. Nevertheless, no direct/indirect interaction partner (upstream/downstream) has been reported for PAC. It has been shown that a specific protein, kinase A (PKA), showed to be involved in phototaxis and gravitaxis. The current study reports the localization of the specific PKA and its relationship with PAC. 相似文献
922.
介绍CVS应用技术。CVS是目前半导体以及电路板业界最受广泛采用,监控电镀液中有机添加剂的技术。CVS精确分析所得的结果,可以用来作为离线或在线添加有机添加剂的依据,以保障槽液的品质。本文详细讨论CVS技术的电化学原理,并提供应用实例以作进一步解说。 相似文献
923.
924.
Tingting Gu Jesper Just Katrine Tang Stenz Yan Yan Peter Sieljacks Jakob Wang Thomas Skjaerlund Groennebaek Jesper Emil Jakobsgaard Emil Rindom Jon Herskind Anders Gravholt Thomas Ravn Lassen Mathias Jrgensen Rikke Bk Eugenio Gutirrez-Jimnez Nina Kerting Iversen Peter Mondrup Rasmussen Jens Randel Nyengaard Malene Mller Jrgensen Frank de Paoli Hans Erik Btker Jrgen Kjems Kristian Vissing Kim Ryun Drasbek 《International journal of molecular sciences》2022,23(6)
Ischemic conditioning and exercise have been suggested for protecting against brain ischemia-reperfusion injury. However, the endogenous protective mechanisms stimulated by these interventions remain unclear. Here, in a comprehensive translational study, we investigated the protective role of extracellular vesicles (EVs) released after remote ischemic conditioning (RIC), blood flow restricted resistance exercise (BFRRE), or high-load resistance exercise (HLRE). Blood samples were collected from human participants before and at serial time points after intervention. RIC and BFRRE plasma EVs released early after stimulation improved viability of endothelial cells subjected to oxygen-glucose deprivation. Furthermore, post-RIC EVs accumulated in the ischemic area of a stroke mouse model, and a mean decrease in infarct volume was observed for post-RIC EVs, although not reaching statistical significance. Thus, circulating EVs induced by RIC and BFRRE can mediate protection, but the in vivo and translational effects of conditioned EVs require further experimental verification. 相似文献
925.
Dale L. Muccignat Peter W. Stokes Daniel G. Cocks Jason R. Gascooke Darryl B. Jones Michael J. Brunger Ronald D. White 《International journal of molecular sciences》2022,23(6)
The extraction of electron–liquid phase cross-sections (surface and bulk) is proposed through the measurement of (differential) energy loss spectra for electrons scattered from a liquid micro-jet. The signature physical elements of the scattering processes on the energy loss spectra are highlighted using a Monte Carlo simulation technique, originally developed for simulating electron transport in liquids. Machine learning techniques are applied to the simulated electron energy loss spectra, to invert the data and extract the cross-sections. The extraction of the elastic cross-section for neon was determined within 9% accuracy over the energy range 1–100 eV. The extension toward the simultaneous determination of elastic and ionisation cross-sections resulted in a decrease in accuracy, now to within 18% accuracy for elastic scattering and 1% for ionisation. Additional methods are explored to enhance the accuracy of the simultaneous extraction of liquid phase cross-sections. 相似文献
926.
Peter W.M. John 《技术计量学》2013,55(3):641-642
A solution is given to the problem of finding a balanced incomplete block design for 18 varieties in 51 blocks of six plots each. The design is obtained by combining group divisible partially balanced designs and duplicating some of the blocks. 相似文献
927.
928.
Elke Rauscher-Gabernig Roland Grossgut Friedrich Bauer Peter Paulsen 《Food Control》2009,20(4):423-429
Although alimentary intake of histamine can cause intoxication, legal limits for histamine content in the EU, exist for certain seafish species only. The present study suggests tolerable levels for fermented sausage, fish and cheese which are based on relating the amount of histamine not expected to cause any health effects after ingestion to typically consumed amounts of food. Limits of 500 and 400 mg/kg would seem to be justifiable for fermented sausage and cheese, respectively. For fish species other than those already regulated in EU, the “m”/”M” limits of 100 and 200 mg/kg can be adopted. These limits can be met by current food technology. 相似文献
929.
The high-strain rate compressive properties of syntactic foams are characterized in this study. This study is performed using
a pulse-shaped Split-Hopkinson Pressure Bar technique. Nine different types of syntactic foams are fabricated with the same
matrix resin system but three different size microballoons and three different microballoon volume fractions. The microballoons
have the same outer radius of 40 μm, but different internal radii leading to a difference in their densities. The volume fractions
of the microballoons in the syntactic foams are maintained at 0.1, 0.3, and 0.6. Analysis is carried out on the effect of
the microballoon radius ratio at each volume fraction on the high-strain rate properties. This approach is helpful in separating
and categorizing the contribution of matrix and microballoons to the dynamic compressive properties of syntactic foams. The
results at high-strain rates are compared to quasi-static strain rate compressive properties of the same material. The results
show that there is little or no significant change in both compressive strength and modulus of syntactic foams at all radius
ratios when tested at strain rates of 400–500/s compared to quasi-static rates. However, higher dynamic strength and stiffness
values are obtained consistently at all radius ratios when tested at 800–1000/s compared to quasi-static values. It is observed
that the radius ratio does not affect the syntactic foam properties significantly when tested at the same high-strain rate
and volume fraction. Scanning electron microscopy is carried out to understand the fracture modes of the syntactic foams. 相似文献
930.
In this paper we investigate the position of a review network within a research specialty; the network of scholars who write
reviews of their colleagues’ work. This is one of the voluntary activities that researchers perform as a prerequisite for
the functioning of the invisible college. We compare this network to other networks within the specialty, and this allows
us to distinguish various roles: stars, influentials, members, reviewers and juniors. As scholars are characterized by different role-configurations, the invisible college becomes stratified. We discuss the
implications for the development of a referee factor and review factor, norms for refereeing and reviewing, and the development
of systems-based research evaluations. 相似文献