Vanadium oxides are promising cathode materials for Zn-ion batteries. However, they are always suffered from inferior performance because of intrinsic sluggish kinetics, poor conductivity and surface elements dissolut...
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Vanadium oxides are promising cathode materials for Zn-ion batteries. However, they are always suffered from inferior performance because of intrinsic sluggish kinetics, poor conductivity and surface elements dissolution. In this work, porous composite of V2O3 nanoparticles embedded in carbon framework is fabricated by pyrolysis of a Vanadium-base MOF. Attributing to the abundant pores, high specific area and conductive carbon framework, the obtained hierarchical composite delivers a high specificcapacity of 240 mAh g-1 at 0.5 A g-1 although the content of carbon is up to 50%, and exhibits a good rate performance with 86.6% retention when the current densities increased from 0.5 to 4 A g-1. Moreover, the cycling performance of the composite is much better than that of commercial V2O3.
Indonesia has great potential in producing large quantities of renewable energy sources, such as biomass. Biogas is a renewable energy source produced from biomass. It is can be developed in agricultural countries pro...
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Indonesia has great potential in producing large quantities of renewable energy sources, such as biomass. Biogas is a renewable energy source produced from biomass. It is can be developed in agricultural countries producing rice and coffee, where a large amount of waste is produced in the form of rice husks and coffee grounds. This study examined the effect of physiochemical pretreatment and the c/N ratio on biogas production using coffee grounds and rice husk mixtures. Physical pretreatment was conducted by grinding the mixture up to 50 mesh size, followed by chemical pretreatment by soaking the mixture in 3% KOH;moreover, the variation in the c/N ratio was set at 25 and 30. Anaerobic bacteria were acquired from rumen fluid. The ratio of the coffee ground material, rice husks, and rumen fluid was 1:1:1. This research was conducted in duplicate under batch conditions at ambient temperature (25-35 oc) with a digester volume of 1.5 L. Biogas productivity was measured every 2 d for 60 d. The experimental results indicated that biogas production with a c/N ratio of 30 was 13.3-66.5% higher than that with a c/N ratio of 25. The inclusion of physical pretreatment at a c/N ratio of 30 increased biogas production by up to 31.3%. Moreover, the inclusion of a chemical pretreatment at a c/N ratio of 30 resulted in 30.3% higher biogas production. The kinetics model of biogas production showed that a c/N ratio of 30 with physical and alkaline pretreatment can produce maximum biogas yields of 6,619 mL and 6,570 mL, respectively. Overall, both pretreatments sequentially increased the production
centrioles, together with the surrounding peri-centriolar material (PcM), constitute the centrosome, a major microtubule-organizing center of animal cells. Despite being critical in many cells for signaling, motility ...
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centrioles, together with the surrounding peri-centriolar material (PcM), constitute the centrosome, a major microtubule-organizing center of animal cells. Despite being critical in many cells for signaling, motility and division, centrioles can be eliminated in some systems, including in the vast majority of differentiating cells during embryogenesis in caenorhabditis elegans. Whether the cells retaining centrioles in the resulting L1 larvae do so because they lack an activity that eliminates centrioles in the other cells is not known. Moreover, the extent to which centrioles and PcM remain present in later stages of worm development, when all cells but those of the germ line are terminally differentiated, is not known. Here, by fusing cells that lack centrioles with cells that retain them, we established that L1 larvae do not possess a diffusible elimination activity sufficient to remove centrioles. Moreover, analyzing PcM core proteins in L1 larval cells that retain centrioles, we found that some such proteins, but not all, are present as well. Furthermore, we uncovered that foci of centriolar proteins remain present in specific terminally differentiated cells of adult hermaphrodites and males, in particular in the somatic gonad. correlating the time at which cells were born with the fate of their centrioles revealed that it is not cell age, but instead cell fate, that determines whether and when centrioles are eliminated. Overall, our work maps the localization of centriolar and PcM core proteins in the post-embryonicc. elegans lineage, thereby providing an essential blueprint for uncovering mechanisms modulating their presence and function.
Different parts of corchorus olitorius and c. capsularis possess different antioxidant compounds. This study investigated the phytochemical components and antioxidant capacities of ultrasoundassisted extraction of dif...
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Different parts of corchorus olitorius and c. capsularis possess different antioxidant compounds. This study investigated the phytochemical components and antioxidant capacities of ultrasoundassisted extraction of different plant parts of both species using spectrophotometry at various phenological stages. Results also indicate that leaves, stems and roots of c. olitorius at various growth stages showed higher phytochemical components and antioxidant potential compared to c. capsularis. The phytochemical components from roots to leaves in c. olitorius including total polyphenol 0.97-11.11 mg GAE/g DW, total flavonoid 0.99-7.78 mg QE/g DW and total tannin 4.02-26.89 TA E/g DW, whereas c. capsularis total polyphenol 1.04-7.93 mg GAE/g DW, total flavonoid 0.77-5.5.92 mg QE/g DW and total tannin content 3.17-22.73 TA E/g DW. c. olitorius produced overall 22.23%, 13.61%, 12.24% higher total polyphenol, total flavonoid and total tannin, respectively compare to c. capsularis. Different parts extract also significantly affected antioxidant capacities including DPPH, ABTS, and FRAP activity with values of 22.03-79.46% inhibition, 10.84-104.10 & mu;mol TE/g DW, and 10.84-104.10 & mu;mol Fe2+/g DW respectively for c. olitorius, while c. capsularis demonstrated 14.03-70.97% of DPPH inhibition, 9.16-95.60 & mu;mol TE/g DW of ABTS and 5.31-71.82 & mu;mol Fe2+/g DW of FRAP activity. Moreover, leaves of the flowering stage, young stems and aged roots of both species displayed a higher content of phytochemical and antioxidant activities than other growth stages. A positive correlation between the phytochemical and antioxidant potential indicated that phenolicconstituents solely affected antioxidant activity. Thus, this study established that the plant's parts and phenological growth stages significantly influence the concentration of phytoconstituents and antioxidant activities, and determine the harvesting stages of the different organs of c. olitorius and c. capsularis for consid
Background: Activation of TLR3 receptors, which are sensitive to viral infection, has emerged as a possible mechanism that increases alcohol intake in rodents. Objectives: These studies examined whether a history of e...
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Background: Activation of TLR3 receptors, which are sensitive to viral infection, has emerged as a possible mechanism that increases alcohol intake in rodents. Objectives: These studies examined whether a history of ethanol dependence exacerbated the increase in drinking driven by the TLR3 agonist poly I:c. Methods: Male c57BL/6J mice (>10 per group) were given access to ethanol (20% v/v) 2 hours a day following a history of home cage drinking or after having been rendered ethanol-dependent using a chronic intermittent ethanol (cIE) vapor model. After testing multiple doses, a 5 mg/kg repeated poly I:cchallenge was used to probe the effects of repeated immune challenge, alone or in conjunction with repeated cycles of cIE, on voluntary drinking. An ethanol (12% v/v) operant self-administration model was used to test the effects of poly I:c on stress-induced reinstatement of ethanol seeking and consumption. Results: Poly I:c in naive animals resulted in transient, modest increases in ethanol intake in the home cage and in self-administration (p < 0.05). However, poly I:cchallenge resulted in sensitized stress-induced ethanol consumption and evoked a strong and persistent escalation of drinking in mice with a history of dependence (p < 0.05 for both). conclusion: Activation of viral immune defense may affect ethanol consumption in dependence and sensitivity to future stressors. As patients who suffer from alcohol use disorder are at a heightened risk for viral infection, this interaction could generate risk factors for exacerbating behaviors associated with Alcohol Use Disorders via an immune mechanism.
The genes that encode ribosomal RNAs are present in several hundred copies in most eukaryotes. These vast arrays of repetitive ribosomal DNA (rDNA) have been implicated not just in ribosome biogenesis, but also aging,...
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The genes that encode ribosomal RNAs are present in several hundred copies in most eukaryotes. These vast arrays of repetitive ribosomal DNA (rDNA) have been implicated not just in ribosome biogenesis, but also aging, cancer, genome stability, and global gene expression. rDNA copy number is highly variable among and within species;this variability is thought to associate with traits relevant to human health and disease. Here we investigate the phenotypicconsequences of multicellular life at the lower bounds of rDNA copy number. We use the model caenorhabditis elegans, which has previously been found to complete embryogenesis using only maternally provided ribosomes. We find that individuals with rDNA copy number reduced to similar to 5% of wild type are capable of further development with variable penetrance. Such individuals are sterile and exhibit severe morphological defects, particularly in post-embryonically dividing tissues such as germline and vulva. Developmental completion and fertility are supported by an rDNA copy number similar to 10% of wild type, with substantially delayed development. Worms with rDNA copy number reduced to similar to 33% of wild type display a subtle developmental timing defect that was absent in worms with higher copy numbers. Our results support the hypothesis that rDNA requirements vary across tissues and indicate that the minimum rDNA copy number for fertile adulthood is substantially less than the lowest naturally observed total copy number. The phenotype of individuals with severely reduced rDNA copy number is highly variable in penetrance and presentation, highlighting the need for continued investigation into the biological consequences of rDNA copy number variation.
The sorption properties of the new Al2O3||ccomposite were studied. A feature of its macroscopic morphology and structure is the amorphous state of alumina generated in an inert atmosphere in chemical contact with the...
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The sorption properties of the new Al2O3||ccomposite were studied. A feature of its macroscopic morphology and structure is the amorphous state of alumina generated in an inert atmosphere in chemical contact with the graphene-like carbon surface. This feature is shown to determine the high chemical activity of the alumina-based composite (Ac) in an aqueous medium, which is comparable with the activity of alpha-Al2O3 or gibbsite Al(OH)(3). The sorption properties of the obtained composite towards La(III), ce(III), U(VI) ions are described within the surface complexation model. The agreement between the values of the first hydrolysis constant of La(III), ce(III), and U(VI) cations calculated from the sorption experiment and published data proves the adequacy of the chosen sorption model. It follows from simulation that the sorption activity of the composite is caused by a higher constant (K-1a) of the acid dissociation of -OH2surf+ groups (pK(1a) = 3.9) of the amorphous Ac surface and the partial distribution coefficients of individual hydroxo complexes of the studied cations. Sorption of ions by the composite in a solution of humic acids (HA) is completely determined by the parallel reaction of competitive sorption of protonated HA anions by the amorphous Ac surface in the HA concentration range of 10-200 mg/L. Al2O3||c is an effective sorbent for trace amounts of La(III), ce(III), U(VI), their chemical analogs, and humic acid in natural and working solutions with a low salt background.
Liposome-mediated delivery is a possible means to overcome several shortcomings with c. elegans as a model for identifying and testing drugs that retard aging. These include confounding interactions between drugs and ...
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Liposome-mediated delivery is a possible means to overcome several shortcomings with c. elegans as a model for identifying and testing drugs that retard aging. These include confounding interactions between drugs and the nematodes' bacterial food source and failure of drugs to be taken up into nematode tissues. To explore this, we have tested liposome-mediated delivery of a range of fluorescent dyes and drugs in c. elegans. Liposome encapsulation led to enhanced effects on lifespan, requiring smaller quantities of compounds, and enhanced uptake of several dyes into the gut lumen. However, one dye (Texas red) did not cross into nematode tissues, showing that liposomes cannot ensure the uptake of all compounds. Of six compounds previously reported to extend lifespan (vitamin c, N-acetylcysteine, glutathione (GSH), trimethadione, thioflavin T (ThT), and rapamycin), this effect was reproduced for the latter four in a condition-dependent manner. For GSH and ThT, antibiotics abrogated life extension, implying a bacterially mediated effect. With GSH, this was attributable to reduced early death from pharyngeal infection and associated with alterations of mitochondrial morphology in a manner suggesting a possible innate immune training effect. By contrast, ThT itself exhibited antibiotic effects. For rapamycin, significant increases in lifespan were only seen when bacterial proliferation was prevented. These results document the utility and limitations of liposome-mediated drug delivery for c. elegans. They also illustrate how nematode-bacteria interactions can determine the effects of compounds on c. elegans lifespan in a variety of ways.
The c-2 carbon-concentrating mechanism increases net cO2 assimilation by shuttling photorespiratory cO2 in the form of glycine from mesophyll to bundle sheath cells, where cO2 concentrates and can be re-assimilated. T...
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The c-2 carbon-concentrating mechanism increases net cO2 assimilation by shuttling photorespiratory cO2 in the form of glycine from mesophyll to bundle sheath cells, where cO2 concentrates and can be re-assimilated. This glycine shuttle also releases NH3 and serine into the bundle sheath, and modelling studies suggest that this influx of NH3 may cause a nitrogen imbalance between the two cell types that selects for the c-4 carbon-concentrating mechanism. Here we provide an alternative hypothesis outlining mechanisms by which bundle sheath NH3 and serine play vital roles to not only influence the status of c-2 plants along the c-3 to c-4 evolutionary trajectory, but to also convey stress tolerance to these unique plants. Our hypothesis explains how an optimized bundle sheath nitrogen hub interacts with sulfur and carbon metabolism to mitigate the effects of high photorespiratory conditions. While c-2 photosynthesis is typically cited for its intermediary role in c-4 photosynthesis evolution, our alternative hypothesis provides a mechanism to explain why some c-2 lineages have not made this transition. We propose that stress resilience, coupled with open flux tricarboxylic acid and photorespiration pathways, conveys an advantage to c-2 plants in fluctuating environments. An alternative theory for bundle sheath ammonia tolerance in c(2)species suggests that c(2)to c(4)evolutionary transitions may depend on bundle sheath nitrogen hub optimization.
An Au-doped nanostructured TiO2/c material was synthesized by a facile approach via calcination of Ti-based metal-organic-framework (MIL-125) with Au-doped from HAucl4 and was used to fabricate a modified glassy carbo...
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An Au-doped nanostructured TiO2/c material was synthesized by a facile approach via calcination of Ti-based metal-organic-framework (MIL-125) with Au-doped from HAucl4 and was used to fabricate a modified glassy carbon electrode (GcE) for detection of ferulic acid (FA). The composition and morphology of TiO2/c/Au were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The redox properties were investigated by cyclic voltammetry and differential pulse voltammetry. Under optimized conditions, the reported sensor not only exhibited high selectivity, but also showed a wide linear range over FA concentrations from 0 to 20.0 mu M with a low detection limit of 1.6 x 10(-8 )mol/L, attributed to advantageously high electron transfer efficiency.
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