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1.
Circular RNAs (circRNAs) are a large class of relatively stable RNA molecules that are highly expressed in animal brains. Many circRNAs have been associated with CNS disorders accompanied by an aberrant wake-sleep cycle. However, the regulation of circRNAs in brain homeostasis over daily light-dark (LD) cycles has not been characterized. Here, we aim to quantify the daily expression changes of circRNAs in physiological conditions in healthy adult animals. Using newly generated and public RNA-Seq data, we monitored circRNA expression throughout the 12:12 h LD cycle in various mouse brain regions. We identified that Cdr1as, a conserved circRNA that regulates synaptic transmission, is highly expressed in the suprachiasmatic nucleus (SCN), the master circadian pacemaker. Despite its high stability, Cdr1as has a very dynamic expression in the SCN throughout the LD cycle, as well as a significant regulation in the hippocampus following the entry into the dark phase. Computational integration of different public datasets predicted that Cdr1as is important for regulating light entrainment in the SCN. We hypothesize that the expression changes of Cdr1as in the SCN, particularly during the dark phase, are associated with light-induced phase shifts. Importantly, our work revises the current beliefs about natural circRNA stability and suggests that the time component must be considered when studying circRNA regulation.  相似文献   
2.
Given the energy problem that our society is facing, interest has been growing in the so-called hydrogen economy. In this system, fuel cells play an essential part. This paper gives an overview of the different materials currently thought to be potential proton exchange membrane materials for fuel cells operated at medium temperatures (100-200 °C). This includes perfluorosulfonic acid (PFSA) membranes like Nafion® but Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9, Franceese materials will be given. The most frequently used experimental techniques to study the morphology of these membrane materials and their proton conduction mechanisms and water transport will be reviewed and presented. The aim of this review is double: to help scientists and science managers not yet in this field to easily gain an overview of the state-of-the-art membrane materials and the experimental techniques used to study them; and to give insight to scientists already carrying out research on membrane materials on how to extend their research either on other materials or with other experimental techniques.  相似文献   
3.
Within the framework of solvent diffusion in glassy polymers, this paper concerns an experimental study of toluene sorption and desorption in P(MMA/nBMA) copolymer films. Gravimetric experiments (quartz microbalance) are performed in a pressure and temperature controlled chamber. Coupling between solvent diffusion and viscoelastic relaxation is taken into account through the time-dependent solubility model, based on the Fick diffusion equation inside the film and a time variable boundary condition at the film/vapor interface. Viscoelastic relaxation is described by a first order model or by a stretched exponential. In the present paper, a special focus is given on the set inversion method used to analyze the data and to derive well-defined uncertainty intervals upon each determined quantity, taking all the uncertainties on the weight measurements into account. We find that the mutual diffusion coefficient strongly decreases in the glassy state, of about two orders of magnitude for a 0.05 decrease in the solvent weight fraction.  相似文献   
4.
Childhood psychosocial trauma (sexual, physical, and emotional abuse) influences perceptions and expectations about interpersonal relations. This study tests the hypothesis that these influences can be assessed through measurement of interpersonal complementarity. Self-reports of perceptions of relationships with childhood abuse initiators are examined for a clinical sample of 20 dissociative disorder patients (aged 19–52 yrs) using Structural Analysis of Social Behavior. Patient ratings of their relationships with abuse initiators showed marked deviations from complementarity. Substantial appeasement of the abuser was also indicated in the ratings. Implications for psychotherapy of abuse victims are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Venous thromboembolism (VTE) is the third leading cardiovascular cause of death and is conventionally treated with anticoagulants that directly antagonize coagulation. However, recent data have demonstrated that also platelets play a crucial role in VTE pathophysiology. In the current review, we outline how platelets are involved during all stages of experimental venous thrombosis. Platelets mediate initiation of the disease by attaching to the vessel wall upon which they mediate leukocyte recruitment. This process is referred to as immunothrombosis, and within this novel concept inflammatory cells such as leukocytes and platelets directly drive the progression of VTE. In addition to their involvement in immunothrombosis, activated platelets can directly drive venous thrombosis by supporting coagulation and secreting procoagulant factors. Furthermore, fibrinolysis and vessel resolution are (partly) mediated by platelets. Finally, we summarize how conventional antiplatelet therapy can prevent experimental venous thrombosis and impacts (recurrent) VTE in humans.  相似文献   
6.
Samples of the cheese yeast Rhodotorula glutinis were analysed during storage at +4 degrees C for cultivability, viability, vitality (metabolic activity), membrane potential state, intracellular pH, and carbohydrate content. The results have allowed to describe cellular events occurring during storage. The loss of vitality came with the decrease of carbohydrate content. The fall of trehalose content under a threshold value induced the deterioration of the membrane potential. Later, when all the cells were depolarised, the intracellular pH decreased and the cultivability dropped, whereas viable cells still decreased slowly. Then, it led to an intermediate physiological state similar to the viable but non-cultivable state. Finally, the fall of viability dropped. In this work, we have defined rapid methods relevant to describe the sequence of intracellular events in the cheese yeast R. glutinis during storage, and we applied them to understand the weak vitality without fall of viability of yeast samples. These methods might allow to rapidly test yeast sample quality before use and to predict, at the moment of the harvesting, the conservation of the yeast.  相似文献   
7.
Athletes and their coach interpret the training situations differently and this can have important implications for the development of an elite athlete's performance. It is argued that, from a schema-theoretic perspective, the difference in these interpretations needs to be better understood. A post-performance, self-confrontation, interview was conducted with a number of athletes and their coaches. The interviews revealed differences between the athlete and their coach in the information they are aware of. In comparison with athletes, coaches more frequently compared the phenotype with genotype schemata rather than just describing the phenotype schemata. Results suggest SA information elements showed some common ground but also revealed some important differences between the athlete and coach. The awareness was directed externally towards the environment and internally, towards the individual, depending on his/her role. The investigation showed that the schemata used to ‘frame’ the information elements were different, but compatible, between athlete and coach.  相似文献   
8.
The present study was the first to investigate infants' ability to discriminate time using a bisection task that has been extensively used with animals and human adults. Infants aged 4 months were presented with two standard auditory signals, one short (S = 500 ms) and one long (L = 1,500 ms), and were trained either to look to the left after S and to the right after L, or vice versa. During the test phase, the infants were then presented with intermediate durations without reinforcement as well as the two reinforced standard durations, for which the reinforcement was either immediate or delayed of 3 s. The times spent by the infants looking to the right, left or away from the target after the stimulus duration were coded by two blind coders. The results revealed an orderly psychophysical function with the proportion of long responses increasing with signal duration. The point of subjective equality (Bisection Point) was closer to the geometric mean of the short and long standard duration than to their arithmetic mean. Modeling using the scalar timing models revealed that our infants had a relatively high sensitivity to time but that their temporal performance was affected by the fact that they made a large number of random responses. The development of the perception of time is discussed in the light of similarities and differences in temporal bisection performance between different species (rats and humans) and the different levels of development observed within a given species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The kinetic behavior of a nitrifying sludge exposed to 2-chlorophenol (2-CP) was evaluated in batch culture. The assays were performed using a stabilized nitrifying sludge. In control assays with (mg L(-1)): NH(4)(+)-N (100) and NaHCO(3)(-)-C (250), the substrates were consumed in 8h, the ammonium consumption efficiency was 99% and the NO(3)(-) yield higher than 0.9. When 5mg 2-CP-C L(-1) was added, it was transformed into an unidentified intermediate and the nitrifying efficiency decreased to 10%. Ammonium specific consumption rate diminished 95%, but the NO(3)(-) yield remained higher than 0.9. The biomass previously exposed to 2-CP was newly suspended with NH(4)(+)-N or NO(2)(-)-N in order to evaluate the ammonium and nitrite oxidizing processes. The consumption efficiencies and NO(3)(-) yields were similar to those obtained in control assays. However, the total time required for ammonium and nitrite consumption increased to 120 and 42 h, respectively. Specific consumption rates for NH(4)(+)-N and NO(2)(-)-N decreased by 95% and 83% respectively, compared to control assays. Thus, the previous contact to 2-CP had more influence on ammonium oxidizing process than the nitrite oxidizing process. These are the first evidences where a nitrifying sludge exposed to 2-CP are reported.  相似文献   
10.
Comparative analysis of CRISPR loci in lactic acid bacteria genomes   总被引:1,自引:0,他引:1  
Clustered regularly interspaced short palindromic repeats (CRISPR) are hypervariable loci widely distributed in bacteria and archaea, that provide acquired immunity against foreign genetic elements. Here, we investigate the occurrence of CRISPR loci in the genomes of lactic acid bacteria (LAB), including members of the Firmicutes and Actinobacteria phyla. A total of 102 complete and draft genomes across 11 genera were studied and 66 CRISPR loci were identified in 26 species. We provide a comparative analysis of the CRISPR/cas content and diversity across LAB genera and species for 37 sets of CRISPR loci. We analyzed CRISPR repeats, CRISPR spacers, leader sequences, and cas gene content, sequences and architecture. Interestingly, multiple CRISPR families were identified within Bifidobacterium, Lactobacillus and Streptococcus, and similar CRISPR loci were found in distant organisms. Overall, eight distinct CRISPR families were identified consistently across CRISPR repeats, cas gene content and architecture, and sequences of the universal cas1 gene. Since the clustering of the CRISPR families does not correlate with the classical phylogenetic tree, we hypothesize that CRISPR loci have been subjected to horizontal gene transfer and further evolved independently in select lineages, in part due to selective pressure resulting from phage predation. Globally, we provide additional insights into the origin and evolution of CRISPR loci and discuss their contribution to microbial adaptation.  相似文献   
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