Oxidized/partially reduced hexagonal (h-) and monoclinic (m-) WO3 nanoparticles were tested as photocatalysts both in the aqueous and in the gaseous phase. Unlike other semiconductor oxides, WO3 is ...unique in that its composition is decisive for photocatalysis, while its crystal structure has only an indirect role. Display omitted
► Oxidized/partially reduced h- and m-WO3 nanoparticles were prepared. ► Composition is decisive for WO3: the more oxidized, the better photocatalyst. ► Crystal structure of WO3 has only secondary role through affecting composition. ► Lower activity of reduced WO3 is due to W5+/W4+ atoms and less surface OH. ► We predict that tungsten bronzes and cubic WO3 are worse photocatalysts than m-WO3.
Hexagonal (h-) and monoclinic (m-) WO3 nanoparticles with controlled composition (oxidized/yellow color or partially reduced/blue color) were prepared through annealing (NH4)xWO3−y. The formation, structure, composition, morphology, and optical properties of the samples were analyzed by powder X-ray diffraction, scanning and transmission electron microscopy combined with electron diffraction, and Raman, X-ray photoelectron, 1H magic angle spinning nuclear magnetic resonance, diffuse reflectance ultraviolet–visual, and photoluminescence spectroscopy. Their photocatalytic properties were tested by decomposing methyl orange in the aqueous phase and acetone in the gas phase. Oxidized m-WO3 (m-WO3 ox) was the most active photocatalyst both in the aqueous and in the gas phase, followed by the oxidized h-WO3 (h-WO3 ox) sample. Reduced h-WO3 (h-WO3 red) and m-WO3 (m-WO3 red) exhibited much lower activity. Thus, in contrast to TiO2, where crystalline structure (rutile or anatase) plays a key effect in photocatalysis, for WO3, it is the composition that is of greatest importance: the more oxidized the WO3 sample, the better a photocatalyst it is. The crystal structure of WO3 has only an indirect effect, in that it influences the composition of WO3 samples. While oxidized m-WO3 is completely oxidized, oxidized h-WO3 is always in a partially reduced state due to the presence of stabilizing positive ions in its hexagonal channels. Consequently, an oxidized monoclinic WO3 material will always provide better photocatalytic activity than an oxidized hexagonal one.
In recent electronic industry, the assembly of electronic components on Printed Circuit Boards (PCB) is one of the most crucial tasks. Here, gantry type placement machines are popular because of the ...flexibility of their configurations. The Machine Configuration and (Work) Load Balancing (MCLB) problem determines the proper configurations of the machine modules in the assembly line and the allocation of the component placements among the modules minimizing the total production time. This is a difficult optimization problem, especially when the assembly line produces several batches of multiple PCB types using a common machine setup for all PCB types. In the present study, a graph model and a mathematical formulation are given for the multi-model problem (MCLB-M). A heuristic method is also presented, called Divide and Combine (DaC), which divides the multi-model problem into single product problems and solves them independently. The solutions are then combined to form a common sub-configuration of the modules. Finally, the global problem is solved by reducing its size using the fixed sub-configuration. The presented method is independent of the optimization algorithms used for the sub-problems; an integer programming model and a heuristic algorithm are used for the single problems, and an integer programming for the reduced global problem. The tests showed that the DaC method is robust and works well for problems of different size.
Enzymes are considered to be a key soil component catalysing important transformations related to decomposition and nutrient turnover, and their activity in soil can be used as a measure of soil ...health. As part of the Síkfőkút DIRT (Detritus Input and Removal Treatments) Project in a temperate deciduous forest in northern Hungary, we examined the extent to which enzyme activity in soil is influenced by both the quality and quantity of plant detrital inputs. DIRT treatments include doubling of leaf litter and woody debris inputs as well as removal of litter and trenching to prevent root inputs. Our objective was to examine seasonal dynamics of soil phosphatase and β-glucosidase activities and to determine the effects of detrital manipulations on these dynamics. We found that the litter additions did not affect enzyme activities, but removal of roots caused significant decreases in enzyme activities. We conclude that plant-induced changes to soil enzyme activities are driven primarily by readily available, labile carbon provided by root turnover and root exudation rather than by aboveground detrital inputs. However, these results could also have been affected by changes in soil chemistry with detrital input removal: after only 6 years of litter removal, soil cation content decreased and soils became more acidic, both of which could inhibit enzyme activity. The soil phosphatase and β-glucosidase enzymes measured showed similar seasonal dynamics. Both enzymes showed the highest activities in spring coincident with high soil moisture and, presumably, high root activity. The minimal response of soil enzyme activity to dramatic litter additions suggests a level of resilience in ecosystem function in this forest, and suggests that aboveground litter is not a significant source of labile carbon to microbes in the mineral soil.
•Litter additions did not affect enzyme activities.•Detritus removal significantly reduced enzyme activities.•Root removal significantly reduced enzyme activities.•Enzyme activity are driven primarily by labile carbon.•Aboveground litter is not a significant source of labile carbon to microbes.
This paper discusses the formation of nanosized hexagonal tungsten oxide (h-WO3) during the annealing of hexagonal ammonium tungsten bronze (HATB), (NH4)0.33−x WO3−y . This process was investigated ...by TG/DTA-MS, XRD, SEM, Raman, XPS, and 1H-MAS NMR analyses. Through adjusting the temperature and atmosphere of annealing HATB, the composition (W oxidation state, residual NH4 + and NH3 content) of h-WO3 could be controlled. The effect of composition on the conductivity and gas sensitivity of h-WO3 was studied. New structural information was obtained about both HATB and h-WO3. It was found that NH4 + and NH3 could be situated at three different positions in HATB. Residual NH4 + and NH3 in the hexagonal channels seemed to be vital for stabilizing h-WO3: when they were completely released, the hexagonal framework collapsed. We propose that the structure of h-WO3 cannot be maintained without some stabilizing ions or molecules in the hexagonal channels.
The prevalence of autism spectrum disorder (ASD) has rapidly increased in the past decades, and several studies report about the escalating use of antibiotics and the consequent disruption of the ...gastrointestinal microbiome leading to the development of neurobehavioral symptoms resembling to those of ASD. The primary purpose of this study was to investigate whether depletion of the gastrointestinal microbiome via antibiotics treatment could induce ASD-like behavioral symptoms in adulthood. To reliably evaluate that, validated valproic acid (VPA) ASD animal model was introduced. At last, we intended to demonstrate the assessed potential benefits of a probiotic mixture (PM) developed by our research team. Male Wistar rats were used to create antibiotics treated; antibiotics and PM treated; PM treated, VPA treated; VPA and PM treated; and control groups. In all investigations we focused on social behavioral disturbances. Antibiotics-induced microbiome alterations during adulthood triggered severe deficits in social behavior similar to those observed in the VPA model. Furthermore, it is highlighted that our PM proved to attenuate both the antibiotics- and the VPA-generated antisocial behavioral symptoms. The present findings underline potential capacity of our PM to improve social behavioral alterations thus, indicate its promising therapeutic power to attenuate the social-affective disturbances of ASD.
Orderly chromosome segregation is enabled by crossovers between homologous chromosomes in the first meiotic division. Crossovers arise from recombination-mediated repair of programmed DNA ...double-strand breaks (DSBs). Multiple DSBs initiate recombination, and most are repaired without crossover formation, although one or more generate crossovers on each chromosome. Although the underlying mechanisms are ill-defined, the differentiation and maturation of crossover-specific recombination intermediates requires the cyclin-like CNTD1. Here, we identify PRR19 as a partner of CNTD1. We find that, like CNTD1, PRR19 is required for timely DSB repair and the formation of crossover-specific recombination complexes. PRR19 and CNTD1 co-localise at crossover sites, physically interact, and are interdependent for accumulation, indicating a PRR19-CNTD1 partnership in crossing over. Further, we show that CNTD1 interacts with a cyclin-dependent kinase, CDK2, which also accumulates in crossover-specific recombination complexes. Thus, the PRR19-CNTD1 complex may enable crossover differentiation by regulating CDK2.
Pharmacological effects of ketamine may affect homeostatic sleep regulation via slow wave related mechanisms.
In the present study effects of ketamine applied at anesthetic dose (80 mg/kg) were ...tested on neocortical electric activity for 24 h in freely moving rats. Ketamine effects were compared to changes during control (saline) injections and after 6 h gentle handling sleep deprivation (SD). As circadian factors may mask drug effects, an illumination protocol consisting of short light-dark cycles was applied.
Ketamine application induced a short hypnotic stage with characteristic slow cortical rhythm followed by a long-lasting hyperactive waking resulting pharmacological SD. Coherence analysis indicated an increased level of local synchronization in broad local field potential frequency ranges during hyperactive waking but not during natural- or SD-evoked waking. Both slow wave sleep and rapid eye movement sleep were replaced after the termination of the ketamine effect.
Our results show that both ketamine-induced hypnotic state and hyperactive waking can induce homeostatic sleep pressure with comparable intensity as 6 h SD, but ketamine-induced waking was different compared to the SD-evoked one. Both types of waking stages were different compared to spontaneous waking but all three types of wakefulness can engage the homeostatic sleep regulating machinery to generate sleep pressure dissipated by subsequent sleep. Current-source density analysis of the slow waves showed that cortical transmembrane currents were stronger during ketamine-induced hypnotic stage compared to both sleep replacement after SD and ketamine application, but intracortical activation patterns showed only quantitative differences.
These findings may hold some translational value for human medical ketamine applications aiming the treatment of depression-associated sleep problems, which can be alleviated by the homeostatic sleep effect of the drug without the need for an intact circadian regulation.
•Ketamine sleep effect using short light-dark cycle lighting regime in male rats•Ketamine affects homeostatic sleep regulation.•Ketamine-induced waking results same homeostatic sleep response as sleep deprivation.•Similar cortical currents during sleep rebound after ketamine and sleep deprivation.
BACKGROUND AND AIMS: We examined the influence of litter quality and litter depth on soil microclimate in the detrital manipulation plots in the Síkfőkút Detrital Input and Removal Treatments (DIRT) ...experiment in northeastern Hungary. We measured the soil temperatures from 06.01.2001 to 06.16.2008 and air temperature from 06.17.2004 to 06.16.2008. METHODS: DIRT manipulations include two litter addition and three litter removal treatments, and one Control. RESULTS: There were significant differences detected among plots in winter and summer soil mean temperatures (p < 0.001) as well as in the number of frost-free days. The highest annual soil temperature variation was detected in litter removal treatments, while the lowest variation was in Double Litter plots with the thickest litter layer. The root exclusion treatments had significantly greater soil moisture contents than other treatments due to loss of transpiration. Plots wetter and lower in organic matter showed lower winter temperatures. CONCLUSION: Climate change influences soil temperature and moisture content not only directly, but also through the change of litter production. Litter thickness can reduce the effects of soil temperature extremes and moderate minimum and maximum temperature values. These differences in soil microclimate may have a highly significant, but unrecognized effect on soil carbon balance through effects on microbial processing of litter and soil carbon.
Omecamtiv mecarbil (OM) is a promising novel drug for improving cardiac contractility. We tested the therapeutic range of OM and identified previously unrecognized side effects. The Ca
2+
sensitivity ...of isometric force production (pCa
50
) and force at low Ca
2+
levels increased with OM concentration in human permeabilized cardiomyocytes. OM (1 µM) slowed the kinetics of contractions and relaxations and evoked an oscillation between normal and reduced intracellular Ca
2+
transients, action potential lengths and contractions in isolated canine cardiomyocytes. Echocardiographic studies and left ventricular pressure–volume analyses demonstrated concentration-dependent improvements in cardiac systolic function at OM concentrations of 600–1200 µg/kg in rats. Administration of OM at a concentration of 1200 µg/kg was associated with hypotension, while doses of 600–1200 µg/kg were associated with the following aspects of diastolic dysfunction: decreases in E/A ratio and the maximal rate of diastolic pressure decrement (dP/dt
min
) and increases in isovolumic relaxation time, left atrial diameter, the isovolumic relaxation constant Tau, left ventricular end-diastolic pressure and the slope of the end-diastolic pressure–volume relationship. Moreover, OM 1200 µg/kg frequently evoked transient electromechanical alternans in the rat in vivo in which normal systoles were followed by smaller contractions (and T-wave amplitudes) without major differences on the QRS complexes. Besides improving systolic function, OM evoked diastolic dysfunction and
pulsus alternans
. The narrow therapeutic window for OM may necessitate the monitoring of additional clinical safety parameters in clinical application.
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