•The meteorological data during the working period of air conditioning was measured.•The suitable working range of collector temperature of system was gotten.•The characteristic of hourly and monthly ...total efficiency of system were obtained.•The yearly performance of system was calculated.
Due to the absence of cooling tower and independent on water, the air cooled solar double effect LiBr/H2O absorption cooling system is more convenient to be used in commercial building and household use. The performance with collector temperature is an important field for such system. The paper mainly deals with the performance with collector temperature for the solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city. The parameters of system are: aperture area of collector array is 27m2, tilted angle of collector with respect to the horizontal plane is 20 toward to south evaporator temperature is 5°C and the cooling capacity is 20kW. The simulation is based on the meteorological data of monthly typical day which was summarized from a year round measured data. A corresponding parametric model was developed. The hourly and average performance with the collector temperature for monthly typical day was obtained and discussed. It was found that the suitable working range of inlet temperature of collector is 110–130°C to improve performance and lower the risk of crystallization. The difference of hourly total efficiency in 9:00–16:00 is less, and the monthly total efficiency from May to October is approximate. The yearly performance of system including total efficiency, cooling capacity per area of collector and solar fraction was given. Furthermore, the effect of effectiveness of heat exchanger and pressure drop on total efficiency and solar fraction was studied and compared. The paper can serve as a preliminary investigation of solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city, and provides the foundation of further study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK
BACKGROUNDMultiple islet autoantibodies (AAbs) predict the development of type 1 diabetes (T1D) and hyperglycemia within 10 years. By contrast, T1D develops in only approximately 15% of individuals ...who are positive for single AAbs (generally against glutamic acid decarboxylase GADA); hence, the single GADA+ state may represent an early stage of T1D.METHODSHere, we functionally, histologically, and molecularly phenotyped human islets from nondiabetic GADA+ and T1D donors.RESULTSSimilar to the few remaining β cells in the T1D islets, GADA+ donor islets demonstrated a preserved insulin secretory response. By contrast, α cell glucagon secretion was dysregulated in both GADA+ and T1D islets, with impaired glucose suppression of glucagon secretion. Single-cell RNA-Seq of GADA+ α cells revealed distinct abnormalities in glycolysis and oxidative phosphorylation pathways and a marked downregulation of cAMP-dependent protein kinase inhibitor β (PKIB), providing a molecular basis for the loss of glucose suppression and the increased effect of 3-isobutyl-1-methylxanthine (IBMX) observed in GADA+ donor islets.CONCLUSIONWe found that α cell dysfunction was present during the early stages of islet autoimmunity at a time when β cell mass was still normal, raising important questions about the role of early α cell dysfunction in the progression of T1D.FUNDINGThis work was supported by grants from the NIH (3UC4DK112217-01S1, U01DK123594-02, UC4DK112217, UC4DK112232, U01DK123716, and P30 DK019525) and the Vanderbilt Diabetes Research and Training Center (DK20593).
This review summarizes recent progress in the design and fabrication of binder-free electrodes for PIBs, with the focus on the methodologies, detailed strategies and functional materials for ...electrode construction.
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Potassium-ion batteries (PIBs) have attracted enormous attention due to the abundance of potassium resources, low cost, fast ionic conductivity of electrolyte and relatively high operating voltage. Despite great efforts and progress, researches on PIBs are still at the initial stage, especially in the emerging field of flexible and wearable PIBs. The inevitable challenges for PIBs include low reversible capacity, unsatisfactory cycling stability and insufficient energy density, the solution to which mostly relies on designing advanced electrodes. Binder-free electrodes have emerged as promising electrode architecture for PIBs. Such electrodes avoid the use of insulating binders, which can be designed with various synergistic functional materials to address the aforementioned PIB issues and be endowed with flexibility/wearability. In this review, we mainly summarize the recent progress on binder-free electrodes for PIBs, with the focus on the methodologies, detailed strategies and functional materials for electrode construction. One strategy for binder-free electrodes is to assemble free-standing architecture with the help of carbon nanotubes (CNTs), graphitic fibers, and other carbon or mechanically robust materials, either alone or in combination. The other effective strategy is current collector substrate-assisted direct growth, including the use of carbon cloth, metal, MXenes and other conductive substrates. Additionally, challenges and research opportunities are put forward at the end as the guidance for future development of binder-free PIB devices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Willd. (HD) and
(L.) Lam. (HC), two closely related species of the same genus, are both used for health benefits and disease prevention in China. HC is also indiscriminately sold as HD in the ...wholesale chain and food markets. This confusion has led to a growing concern about their identification and quality evaluation. In order to further understand the molecular diversification between them, we focus on the screening of chemical components and the analysis of non-targeted metabolites. In this study, UPLC-QTOF-MS
, UNIFI platform and multivariate statistical analyses were used to profile them. Firstly, a total of 113 compounds, including 80 shared chemical constituents of the two plants, were identified from HC and HD by using the UNIFI platform. Secondly, the differences between two herbs were highlighted with the comparative analysis. As a result, a total of 33 robust biomarkers enabling the differentiation were discovered by using multivariate statistical analyses. For HC, there were 18 potential biomarkers (either the contents were much greater than in HD or being detected only in HC) including three iridoids, eight flavonoids, two tannins, two ketones, one alcohol and two monoterpenes. For HD, there were15 potential biomarkers (either the contents were much greater than in HC or being detected only in HD) including two iridoids, eight flavonoids, one tannin, one ketone, and three anthraquinones. With a comprehensive consideration of the contents or the MS responses of the chemical composition, Hedycoryside A and B, detected only in HC, could be used for rapid identification of HC. The compounds 1,3-dihydroxy-2-methylanthraquinone and 2-hydroxy-3-methylanthraquinone, detected only in HD, could be used for rapid identification of that plant. The systematic comparison of similarities and differences between two confusing Chinese herbs will provide reliable characterization profiles to clarify the pharmacological fundamental substances. HC should not be used as the substitute of HD.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
A new type of scrolled structure of Co(3)O(4)/reduced graphene oxide (r-GO) is facilely prepared through a two-step surfactant-assisted method. This assembly enables almost every single Co(3)O(4) ...scroll to connect with the r-GO platelets, thus leading to remarkable electrochemical performances in terms of high specific capacitance and good rate capability.
Ulcerative colitis (UC) is a chronic, nonspecific inflammation of the bowel that mainly affects the mucosa and submucosa of the rectum and colon. Ginsenosides are the main active ingredients in ...ginseng and show many therapeutic effects in anti-inflammatory diseases, cancer, and nervous system regulation. Protopanaxatriol saponin (PTS) is an important part of saponins, and there is no research on its pharmacological effects on colitis. In this study, a model of ulcerative colitis in mice was induced by having mice freely drink 3.5% dextran sodium sulfate (DSS) solution, and UPLC-Q-TOF-MS-based metabolomics methods were applied to explore the therapeutic effect and protective mechanism of PTS for treating UC. The results showed that PTS could significantly prevent colon shortening and pathological damage and alleviate abnormal changes in UC mouse physiological and biochemical parameters. Moreover, PTS intervention regulated proinflammatory cytokines such as TNF-α, IL-6, and IL-1 in serum, and MPO and NO in colon. Interestingly, PTS could significantly inhibit UC mouse metabolic dysfunction by reversing abnormal changes in 29 metabolites and regulating eleven metabolic pathways. PTS has potential application in the treatment of UC and could alleviate UC in mice by affecting riboflavin metabolism, arachidonic acid metabolism, glycerophospholipid metabolism, retinol metabolism, and steroid hormone biosynthesis and by regulating pentose and glucuronate conversion, linoleic acid metabolism, phenylalanine metabolism, ether lipid metabolism, sphingolipid metabolism, and tyrosine metabolism, which points at a direction for further research and for the development of PTS as a novel natural agent.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The rapid detection of organic matter in soil is of great interest in agriculture, but the commonly used techniques require laboratory operation. Therefore, the development of a technique that allows ...rapid detection of soil organic matter in the field is of great interest. In this work, we propose an electrochemical-based approach for the detection of organic matter in soil particles. Since soil particles immobilized directly on the electrode surface can fall off during testing, we introduced graphene to coat the soil particles. The encapsulated soil particles can be stably immobilized on the electrode surface. We have investigated the electrochemical behavior of soil particles. The results show a correspondence between the electrochemical oxidation and reduction of soil particles and the organic matter content in them. We collected soil samples from three sites and constructed an electrochemical modeling, testing framework with stability based on multiple calibrations and random division of the prediction set. We used the equal interval partial least squares (EC-PLS) method for potential optimization to establish the equivalent model set. A joint model for the electrochemical analysis of organic matter in three locations of soil samples was developed for the commonality study.
Appropriate DNA double-strand break (DSB) repair factor choice is essential for ensuring accurate repair outcome and genomic integrity. The factors that regulate this process remain poorly ...understood. Here, we identify two repressive chromatin components, the macrohistone variant macroH2A1 and the H3K9 methyltransferase and tumor suppressor PRDM2, which together direct the choice between the antagonistic DSB repair mediators BRCA1 and 53BP1. The macroH2A1/PRDM2 module mediates an unexpected shift from accessible to condensed chromatin that requires the ataxia telangiectasia mutated (ATM)-dependent accumulation of both proteins at DSBs in order to promote DSB-flanking H3K9 dimethylation. Remarkably, loss of macroH2A1 or PRDM2, as well as experimentally induced chromatin decondensation, impairs the retention of BRCA1, but not 53BP1, at DSBs. As a result, macroH2A1 and/or PRDM2 depletion causes epistatic defects in DSB end resection, homology-directed repair, and the resistance to poly(ADP-ribose) polymerase (PARP) inhibition—all hallmarks of BRCA1-deficient tumors. Together, these findings identify dynamic, DSB-associated chromatin reorganization as a critical modulator of BRCA1-dependent genome maintenance.
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•RNAi screen implicates macroH2A1 and the H3K9 methyltransferase PRDM2 in HR•PRDM2 and macroH2A1 promote dynamic, ATM-dependent chromatin condensation at DSBs•The macroH2A1/PRDM2 module promotes recruitment of BRCA1, but not 53BP1, to DSBs•Loss of macroH2A1 or PRDM2 impairs BRCA1-dependent genome maintenance
Accurate DNA double-strand break (DSB) repair relies on the choice between two central but opposing repair effectors, BRCA1 and 53BP1, which occupy large, DSB-flanking chromatin domains. The mechanisms that regulate this process remain largely unexplored. Khurana et al. now show that the macrohistone variant macroH2A1 and the H3K9 methyltransferase PRDM2 link the dynamic formation of repressive chromatin at DSBs to selective BRCA1 recruitment, homology-directed repair, and BRCA1-dependent genome maintenance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A loop gravity-assisted heat pipe (LGHP) is characterized by passive heat dissipation and extensive application prospect. Dissimilar working fluids give rise to noticeable differences in their ...working performance (Critical heat flux (CHF)). Consequently, it is of great significance to evaluate the performance of LGHP working fluid for its design. In accordance with the basic theories of CHF and hydrodynamics, the pressure drop models of laminar, smooth turbulence, and completely rough turbulence flows were established, and an extensible two-phase composite property parameter was obtained. On this basis, the physical property parameter of transitional rough turbulent flow was also derived. Finally, as persuasively illustrated by the experimental results, there was almost a linear association between CHFs and the derived physical parameter. As a result, the physical parameters derived in this paper can be employed as favorable criteria for the selection of LGHP working fluid.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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