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Biology achieves remarkable function through processes arising from spontaneous or transient liquid-liquid phase separation (LLPS) of proteins and other biomolecules. While polymeric systems can achieve similar phenomena through simple or complex coacervation, LLPS with supramolecular materials has been less commonly shown. Functional applications for synthetic LLPS systems are an expanding area of emphasis, with particular focus on capturing the transient and dynamic state of these structures for use in biomedicine. Here, a net-cationic supramolecular peptide amphiphile building block with a glucose-binding motif is shown that forms LLPS structures when combined with a net-negatively charged therapeutic protein, dasiglucagon, in the presence of glucose. The droplets that arise are dynamic and coalesce quickly. However, the interface can be stabilized by addition of a 4-arm star PEG. When the stabilized droplets formed in glucose are transferred to a bulk phase containing different glucose concentrations, their stability and lifetime decrease according to bulk glucose concentration. This glucose-dependent formation translates into an accelerated release of dasiglucagon in the absence of glucose; this hormone analogue itself functions therapeutically to correct low blood glucose (hypoglycemia). These droplets also offer function in mitigating the most severe effects of hypoglycemia arising from an insulin overdose through delivery of dasiglucagon in a mouse model of hypoglycemic rescue. Accordingly, this approach to use complexation between a supramolecular peptide amphiphile and a therapeutic protein in the presence of glucose leads to droplets with functional potential to dissipate for the release of the therapeutic material in low blood glucose environments.
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Glicemia , Hipoglicemia , Animais , Camundongos , Glucose , Hipoglicemia/tratamento farmacológico , Hipoglicemia/metabolismo , Proteínas , PolímerosRESUMO
Conductive hydrogels have attracted widespread attention in the fields of biomedicine and health monitoring. However, their practical application is severely hindered by the lengthy and energy-intensive polymerization process and weak mechanical properties. Here, a rapid polymerization method of polyacrylic acid/gelatin double-network organohydrogel is designed by integrating tannic acid (TA) and Ag nanoparticles on conductive MXene nanosheets as catalyst in a binary solvent of water and glycerol, requiring no external energy input. The synergistic effect of TA and Ag NPs maintains the dynamic redox activity of phenol and quinone within the system, enhancing the efficiency of ammonium persulfate to generate radicals, leading to polymerization within 10 min. Also, ternary composite MXene@TA-Ag can act as conductive agents, enhanced fillers, adhesion promoters, and antibacterial agents of organohydrogels, granting them excellent multi-functionality. The organohydrogels exhibit excellent stretchability (1740%) and high tensile strength (184 kPa). The strain sensors based on the organohydrogels exhibit ultrahigh sensitivity (GF = 3.86), low detection limit (0.1%), and excellent stability (>1000 cycles, >7 days). These sensors can monitor the human limb movements, respiratory and vocal cord vibration, as well as various levels of arteries. Therefore, this organohydrogel holds potential for applications in fields such as human health monitoring and speech recognition.
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The development of capable of simultaneously modulating the sluggish electrochemical kinetics, shuttle effect, and lithium dendrite growth is a promising strategy for the commercialization of lithium-sulfur batteries. Consequently, an elaborate preparation method is employed to create a host material consisting of multi-channel carbon microspheres (MCM) containing highly dispersed heterostructure Fe3O4-FeTe nanoparticles. The Fe3O4-FeTe@MCM exhibits a spontaneous built-in electric field (BIEF) and possesses both lithophilic and sulfophilic sites, rendering it an appropriate host material for both positive and negative electrodes. Experimental and theoretical results reveal that the existence of spontaneous BIEF leads to interfacial charge redistribution, resulting in moderate polysulfide adsorption which facilitates the transfer of polysulfides and diffusion of electrons at heterogeneous interfaces. Furthermore, the reduced conversion energy barriers enhanced the catalytic activity of Fe3O4-FeTe@MCM for expediting the bidirectional sulfur conversion. Moreover, regulated Li deposition behavior is realized because of its high conductivity and remarkable lithiophilicity. Consequently, the battery exhibited long-term stability for 500 cycles with 0.06% capacity decay per cycle at 5 C, and a large areal capacity of 7.3 mAh cm-2 (sulfur loading: 9.73 mg cm-2) at 0.1 C. This study provides a novel strategy for the rational fabrication of heterostructure hosts for practical Li-S batteries.
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Inverted organic solar cells (OSCs) have garnered significant interest due to their remarkable stability. In this study, the efficiency and stability of inverted OSCs are enhanced via the in situ self-organization (SO) of an interfacial modification material Phen-NaDPO onto tin oxide (SnO2). During the device fabrication, Phen-NaDPO is spin-coated with the active materials all together on SnO2. Driven by the interactions with SnO2 and the thermodynamic forces due to its high surface energy and the convection flow, Phen-NaDPO spontaneously migrates to the SnO2 interface, resulting in the formation of an in situ modification layer on SnO2. This self-organization of Phen-NaDPO not only effectively reduces the work function of SnO2, but also enhances the ordered molecular stacking and manipulates the vertical morphology of the active layer, which suppress the surface trap-assisted recombination and minimize the charge extraction. As a result, the SO devices based on PM6:Y6 exhibit significantly improved photovoltaic performance with an enhanced power conversion efficiency of 17.62%. Moreover, the stability of the SO device is also improved. Furthermore, the SO ternary devices based on PM6:D18:L8-BO achieved an impressive PCE of 18.87%, standing as one of the highest values for single-junction inverted organic solar cells to date.
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Traditional half-Heusler thermoelectric materials, identified as 18-electron compounds, are characterized by the high power factor and the high lattice thermal conductivity. Interestingly, the emerging 19-electron half-Heusler compounds were also found to be promising thermoelectric materials, but with a 5-10 times lower lattice thermal conductivity. Since the two kinds of compounds have similar chemical and physical structures, such as TiCoSb and VCoSb, the large difference in lattice thermal conductivity is a puzzling question. Here, we present a theoretical study to clarify the lattice thermal transport in half-Heusler thermoelectric materials. Based on electronic band structure analysis, we show that the two transition-metal elements in half-Heusler compounds form the strong and direct d-d interaction that is responsible for the high lattice thermal conductivity of 18-electron compounds. In 19-electron half-Heusler compounds, however, the extra valence electron enters the d-d antibonding states, which significantly weakens the atomic bond strength, leading to a large decrease in the cohesive energy. The resulting softened acoustic phonons enhance the phonon-phonon scattering, and thus reduce the lattice thermal conductivity significantly. By constructing an artificial 18-e compound V0.5Sc0.5CoSb, it is proved that the one less electron relative to VCoSb increases the lattice thermal conductivity significantly.
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Extending the solids retention time (SRT) has been demonstrated to mitigate membrane biofouling. Nevertheless, it remains an intriguing question whether the compact and water flushing resistant mesh biofilms developed at short SRT can undergo biodegradation and be removed with extended SRT. In present study, the bio-fouled mesh filter in the 10d-SRT dynamic membrane bioreactor (DMBR), with mesh surfaces and pores covered by compact and water flushing resistant biofilms exhibiting low water permeability, was reused in the 40d-SRT DMBR without any cleanings. After being reused at 40d-SRT, its flux driven by gravity occurred from the 10th day and recovered to a regular level of 36.7 L m-2·h-1 on the 27th day. Both scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM) analyses indicated that the compact mesh biofilms formed at10d-SRT biodegraded and were removed at 40d-SRT, with the residual biofilms becoming removable by water flushing. As a result, the hydraulic resistance of the bio-fouled mesh filter decreased from 4.36 × 108 to 6.97 × 107 m-1, and its flux fully recovered. The protein and polysaccharides densities in mesh-biofilms decreased from 24.4 to 9.7 mg/cm2 and from 10.7 to 0.10 mg/cm2, respectively, which probably have contributed to the disappearance of compact biofilms and the decrease in adhesion. Furthermore, the sludge and mesh-biofilms in the 40d-SRT reactor contained a higher relative abundance of dominant quorum quenching bacteria, such as Rhizobium (3.52% and 1.35%), compared to those in the 10d-SRT sludge (0.096%) and mesh biofilms (0.79%), which might have been linked to a decline in extracellular polymeric substances and, consequently, the biodegradation and disappearance of compact biofilms.
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Incrustação Biológica , Esgotos , Biofilmes , Incrustação Biológica/prevenção & controle , Filtração , Reatores Biológicos/microbiologia , Membranas ArtificiaisRESUMO
We herein report for the first time the inter- and intramolecular orthogonal cleavage of two ortho-nitrobenzyl (NB) analogues. It is shown that the nitroveratryl (NV) group can be photolyzed with high priority when NV and ortho-nitrobenzyl carbonate (oNBC) are used together as the protecting groups of glycans. Notably, the photolytic products could be used directly in the subsequent glycosylation without further purification. With the above-mentioned orthogonal photolabile protecting group strategy in hand, a Mycobacterium tuberculosis tetrasaccharide and a derivative of glucosyl glycerol were rapidly prepared.
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Mycobacterium tuberculosis , Oligossacarídeos , Glicosilação , Estrutura Molecular , Mycobacterium tuberculosis/química , Nitrobenzenos/química , Oligossacarídeos/química , Oligossacarídeos/síntese químicaRESUMO
Comammox Nitrospira and canonical ammonia-oxidizing bacteria (cAOB) generally coexist in activated sludge. In present study, the effect of comammox Nitrospira on N2O production during nitrification of activated sludge was investigated. Comammox Nitrospira and cAOB were separately enriched in two nitrifying reactors, with respective relative abundance of approximately 98% in ammonia oxidizer community. The N2O emission factor (EF) of nitrification in comammox Nitrospira dominated reactor was 0.35%, consistently lower than that (2.2%) in cAOB dominated reactor. When increasing the relative abundance of comammox Nitrospira in ammonia oxidizer community, the N2O EF of nitrification decreased exponentially, which suggested that comammox Nitrospira not only decreased N2O production directly but also might have reduced N2O yield by cAOB. When cAOB dominated the ammonia oxidizer community of sludge, decreasing pH to 6.3, lowering DO to less than 0.5 mg/L, and increasing nitrite concentration enhanced N2O EF dramatically. When comammox Nitrospira became the dominant ammonia oxidizer, however, the N2O EF correlated to nitrite insignificantly and a low DO of 0.2 mg/L and weakly acidic pH (6.3) decreased N2O EF by approximately 70% and 60%, respectively. These results imply that enhancing the relative abundance of comammox Nitrospira in sludge is an effective way to reducing N2O emissions and can also offset the promoting effects of acidic pH, low DO, and high nitrite concentration on N2O production during nitrification.
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Amônia , Bactérias , Nitrificação , Oxirredução , Esgotos , Amônia/metabolismo , Esgotos/microbiologia , Bactérias/metabolismo , Óxido Nitroso/metabolismo , Nitritos/metabolismo , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos/métodosRESUMO
Objective. Thermoacoustic tomography (TAT) is a promising imaging technique used for early cancer diagnosis, tumor therapy, animal study and brain imaging. Although it is widely known that the TAT frequency response depends on the pulse width of the source and the size of the object, a thorough comprehension of the quantitative frequency modulation in TAT and the mechanism governing the shift in the thermoacoustic pressure spectrum towards lower frequencies with respect to the excitation source is still lacking. This study aims to understand why the acoustic pressure spectrum and the final voltage signals shift towards lower frequencies in TAT.Approach. We employed a linear time-invariant model. In the proposed model, the applied current thermoacoustic imaging (ACTAI) process is divided into the thermoacoustic stage and the acoustoelectric stage. These two stages are characterized by the thermoacoustic transfer function(TATF) and the transducer transfer function (TDTF), respectively. We confirmed the effectiveness of our model through a rigorous examination involving both simulations and experiments.Main results. Simulation results indicate that the TATF behaves as a low-pass filter. The inherent low-pass nature induces a shift towards low frequencies in the acoustic pressure spectrum. Experiments further confirm this behavior, demonstrating that the final electrical voltage also shifts towards low frequencies. Notably, employing the proposed model, there is a remarkable consistency between the main frequency bands of the synthesized and measured final voltage spectrum.Significance. The proposed model thoroughly explains how the TATF causes shifts to low frequencies in both the acoustic pressure spectrum and the final voltage spectrum in TAT. These insights deepen our understanding of optimizing TAT systems in the frequency domain, including aspects like filter design and transducer selection. Furthermore, we underscore the potential significance of this discovery for medical applications, particularly in the context of cancer diagnosis.
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Acústica , Pressão , Tomografia , Tomografia/métodosRESUMO
With the rapid increase of the number of agricultural cooperatives in China, the problem of fake cooperatives has become more and more serious. The core problem is that some members do not use cooperative services, and elite capture phenomenon appears in the organization. Since services are one of the most important public goods attributes of cooperatives, it is important to ensure that more members use them. What are the factors that affect members' utilization level of cooperative services? Existing research does not provide a comprehensive answer. Based on the micro-survey data of 74 citrus cooperatives and 524 citrus members in China, the article found out that 50.9% of the members did not use any services provided by cooperatives, and only 20.04% of the members used cooperatives' sales services. So, this study empirically analyzes the factors that influence the use of cooperatives' services by puns model. The results show that quality of service, service convenience and mountain terrain promote the use of cooperative sales services for members. In addition, cooperative knowledge, planting area, surplus distribution, quality of service, and service convenience significantly increased the utilization leve of cooperative sales services by members. Finally, the study puts forward some suggestions, such as propagating cooperative sales service, improving the quality of cooperative sales service, perfecting cooperative distribution system.
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Comércio , ChinaRESUMO
BACKGROUND: A decrease in semen volume among men is comparable to the rising prevalence of obesity worldwide. The anabolic hormone insulin-like growth factor-1 (IGF-1) can promote proliferation and differentiation in cultured mouse spermatogonial stem cells and alleviate abnormal in vitro spermatogenesis. Additionally, serum IGF-1 level is negatively correlated with body mass index. Whereas the role of IGF-1 in the sperm production in obese men remains unclear. OBJECTIVE: To investigate the therapeutic effect and potential mechanism of IGF-1 on spermatogenesis of high-fat diet (HFD)-induced obesity mice. METHODS: An HFD-induced obesity mouse model was established. Alterations in testicular morphology, sperm count, proliferation, and apoptosis were observed by H&E staining,immunohistochemistry, immunofluorescence, and Western blotting. Exogenous recombinant IGF-1 was administered to obese mice to investigate the correlations between altered testicular IGF-1 levels and sperm production. RESULTS: The sperm count was reduced, the testicular structure was disordered, and sex hormone levels were abnormal in HFD-fed mice compared with normal diet-fed mice. The expression of proliferation-related antigens such as proliferating cell nuclear antigen (PCNA) and Ki-67 was decreased, while that of proapoptotic proteins such as c-caspase3 was increased in testes from HFD-fed mice. Most importantly, the phosphorylation of insulin-like growth factor-1 receptor (IGF-1R) in testes was decreased due to reductions in IGF-1 from hepatocytes and Sertoli cells. Recombinant IGF-1 alleviated these functional impairments by promoting IGF-1R, Akt, and Erk1/2 phosphorylation in the testes. CONCLUSIONS: Insufficient IGF-1/IGF-1R signaling is intimately linked to damaged sperm production in obese male mice. Exogenous IGF-1 can improve survival and proliferation as well as sperm production. This study provides a novel theoretical basis and a target for the treatment of obese men with oligozoospermia.
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Pre-capturing organics in municipal wastewater for biogas production, combined with Anammox-based nitrogen removal process, improves the sustainability of sewage treatment. Thus, enhancing nitrogen removal via Anammox in mainstream wastewater treatment becomes very crucial. In present study, a three-stage anoxic/oxic (AO) biofilm process with intermittent aeration was designed to strengthen partial nitrification/denitrification coupling Anammox (PNA/PDA) in treatment of low C/N wastewater, which contained chemical oxygen demand (COD) of 79.8 mg/L and total inorganic nitrogen (TIN) of 58.9 mg/L. With a hydraulic retention time of 8.0 h, the process successfully reduced TIN to 10.6 mg/L, achieving a nitrogen removal efficiency of 83.3 %. The 1st anoxic zone accounted for 32.0 % TIN removal, with 10.3 % by denitrification and 21.7 % by PDA, meanwhile, the 2nd and 3rd anoxic zones contributed 19.4 % and 4.5 % of TIN removal, primarily achieved through PDA (including endogenous PD coupling Anammox). The 1st and 2nd intermittent zones accounted for 27.2 % and 17.0 % of TIN removal, respectively, with 13.7 %-21.3 % by PNA and 3.2 %-5.3 % by PDA. Although this process did not pursue nitrite accumulation in any zone (< 1.5 mg-N/L), PNA and PDA accounted for 35.1 % and 52.1 % of TIN removal, respectively. Only 0.21 % of removed TIN was released as nitrous oxide. The AnAOB of Candidatus Brocadia was enriched in each zone, with a relative abundance of 0.66 %-2.29 %. In intermittent zones, NOB had been partially suppressed (AOB/NOB = 0.73-0.88), mainly due to intermittent aeration and effective nitrite utilization by AnAOB since its population size was much greater than NOB. Present study indicated that the three-stage AO biofilm process with intermittent aeration could enhance nitrogen removal via PNA and PDA with a low N2O emission factor.
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In recent years, significant attention has been paid to the use of calcium sulfate whiskers (CSWs) to enhance the performance of cement-based materials (CBM). This technology has attracted widespread interest from researchers because it enhances the performance and sustainability of CBM by modifying the crystal structure of calcium sulfate. This article summarizes the fundamental properties and preparation methods of calcium sulfate whisker materials as well as their applications in cement, potential advantages and disadvantages, and practical applications and prospects. The introduction of CSWs has been demonstrated to enhance the strength, durability, and crack resistance of CBM while also addressing concerns related to permeability and shrinkage. The application of this technology is expected to improve the quality and lifespan of buildings, reduce maintenance costs, and positively impact the environment. The use of CSWs in CBM represents a promising material innovation that offers lasting and sustainable advancement in the construction industry.
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Gliomas are the most common malignant tumors of the central nervous system, accounting for approximately 80% of all malignant brain tumors. Accumulating evidence suggest that pyroptosis plays an essential role in the progression of cancer. Unfortunately, the effect of the pyroptosis-related factor caspase-4 (CASP4) on immunotherapy and drug therapy for tumors has not been comprehensively investigated. In this study, we systematically screened six hub genes by pooling differential pyroptosis-related genes in The Cancer Genome Atlas (TCGA) glioma data and the degree of centrality of index-related genes in the protein-protein interaction network. We performed functional and pathway enrichment analyses of the six hub genes to explore their biological functions and potential molecular mechanisms. We then investigated the importance of CASP4 using Kaplan-Meier survival analysis of glioma patients. TCGA and the Chinese Glioma Genome Atlas (CGGA) databases showed that reduced CASP4 expression leads to the potent clinical deterioration of glioma patients. Computational analysis of the effect of CASP4 on the infiltration level and recruitment of glioma immune cells revealed that CASP4 expression was closely associated with a series of tumor-suppressive immune checkpoint molecules, chemokines, and chemokine receptors. We also found that aberrant CASP4 expression correlated with chemotherapeutic drug sensitivity. Finally, analysis at the cellular and tissue levels indicated an increase in CASP4 expression in glioma, and that CASP4 inhibition significantly inhibited the proliferation of glioma cells. Thus, CASP4 is implicated as a new prognostic biomarker for gliomas with the potential to further guide immunotherapy and chemotherapy strategies for glioma patients.
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Neoplasias Encefálicas , Caspases Iniciadoras , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma , Humanos , Glioma/genética , Glioma/patologia , Glioma/imunologia , Prognóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/mortalidade , Caspases Iniciadoras/metabolismo , Caspases Iniciadoras/genética , Piroptose/genética , Mapas de Interação de Proteínas , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Estimativa de Kaplan-Meier , Linhagem Celular TumoralRESUMO
Bi2Te3-based materials play a crucial role in solid cooling and power generation, but the rapidly deteriorated ZT with rising temperatures above 450 K severely limits further applications. Here, this paper reports a novel preparation method of annealing treatment for molten ingot, which can enhance the thermoelectric performance of n-type Bi2Te2.4Se0.6 in a wide temperature range. Instead of conventional halides, copper is adopted to regulate the carrier concentration and grain size to optimal levels. During the process of annealing at 573 K for 4 h, the number of twins significantly increases and the grains of Cu-doped samples become larger and more oriented. These optimizations lead to higher carrier mobility with similar carrier concentration compared with the sample without heat treatment. The synergistic effects of Cu doping and annealing treatment realize a high average ZT of 0.89 within 300-600 K in n-type Cu0.02Bi2Te2.4Se0.6. Combined with p-type (Bi,Sb)2Te3, the fabricated thermoelectric device exhibits a high conversion efficiency of 6.9% at a temperature difference of 300 K. This study suggests that annealing treatment is a simple and effective scheme to promote the applications of n-type Bi2(Te,Se)3 in a wide temperature range.
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Powdery mildew disease (PMD) is caused by the obligate biotrophic fungus Microsphaera diffusa Cooke & Peck (M. diffusa) and results in significant yield losses in soybean (Glycine max (L.) Merr.) crops. By identifying disease-resistant genes and breeding soybean accessions with enhanced resistance, we can effectively mitigate the detrimental impact of PMD on soybeans. We analyzed PMD resistance in a diversity panel of 315 soybean accessions in two locations over 3 years, and candidate genes associated with PMD resistance were identified through genome-wide association studies (GWAS), haplotype analysis, qRT-PCR, and EMS mutant analysis. Based on the GWAS approach, we identified a region on chromosome 16 (Chr16) in which 21 genes form a gene cluster that is highly correlated with PMD resistance. In order to validate and refine these findings, we conducted haplotype analysis of 21 candidate genes and indicated there are single nucleotide polymorphisms (SNPs) and insertion-deletions (InDels) variations of Glyma.16G214000, Glyma.16G214200, Glyma.16G215100 and Glyma.16G215300 within the coding and promoter regions that exhibit a strong association with resistance against PMD. Subsequent structural analysis of candidate genes within this cluster revealed that in 315 accessions, the majority of accessions exhibited resistance to PMD when Glyma.16G214300, Glyma.16G214800 and Glyma.16G215000 were complete; however, they demonstrated susceptibility to PMD when these genes were incomplete. Quantitative real-time PCR assays (qRT-PCR) of possible candidate genes showed that 14 candidate genes (Glyma.16G213700, Glyma.16G213800, Glyma.16G213900, Glyma.16G214000, Glyma.16G214200, Glyma.16G214300, Glyma.16G214500, Glyma.16G214585, Glyma.16G214669, Glyma.16G214700, Glyma.16G214800, Glyma.16G215000, Glyma.16G215100 and Glyma.16G215300) were involved in PMD resistance. Finally, we evaluated the PMD resistance of mutant lines from the Williams 82 EMS mutations library, which revealed that mutants of Glyma.16G214000, Glyma.16G214200, Glyma.16G214300, Glyma.16G214800, Glyma.16G215000, Glyma.16G215100 and Glyma.16G215300, exhibited sensitivity to PMD. Combined with the analysis results of GWAS, haplotypes, qRT-PCR and mutants, the genes Glyma.16G214000, Glyma.16G214200, Glyma.16G214300, Glyma.16G214800, Glyma.16G215000, Glyma.16G215100 and Glyma.16G215300 were identified as highly correlated with PMD resistance. The candidate genes identified above are all NLR family genes, and these discoveries deepen our understanding of the molecular basis of PMD resistance in soybeans and will be useful for guiding breeding strategies.
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Entropy engineering is aneffective scheme to reduce the thermal conductivity of thermoelectric materials, but it inevitably deteriorates the carrier mobility. Here, we report the optimization of thermoelectric performance of PbTe by combining entropy engineering and nanoprecipitates. In the continuously tuned compounds of Pb0.98Na0.02Te(1-2x)SxSex, we show that the x = 0.05 sample exhibits an exceptionally low thermal conductivity relative to its configuration entropy. By introducing Mn doping, the produced temperature-dependent nanoprecipitates of MnSe cause the high-temperature thermal conductivity to be further reduced. A very low lattice thermal conductivity of 0.38 W m-1 K-1 is achieved at 825 K. Meanwhile, the carrier mobility of the samples is only slightly influenced, owing to the well-controlled configuration entropy and the size of nanoprecipitates. Finally, a high peak zT of â¼2.1 at 825 K is obtained in the Pb0.9Na0.04Mn0.06Te0.9S0.05Se0.05 alloy.
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Arsenate [As(V)] reduction is a major cause of arsenic (As) release from soils, which threatens more than 200 million people worldwide. While heterotrophic As(V) reduction has been investigated extensively, the mechanism of chemolithotrophic As(V) reduction is less studied. Since As is frequently found as a sulfidic mineral in the environment, microbial mediated sulfur oxidation coupled to As(V) reduction (SOAsR), a chemolithotrophic process, may be more favorable in sites impacted by oligotrophic mining (e.g. As-contaminated mine tailings). While SOAsR is thermodynamically favorable, knowledge regarding this biogeochemical process is still limited. The current study suggested that SOAsR was a more prevalent process than heterotrophic As(V) reduction in oligotrophic sites, such as mine tailings. The water-soluble reduced sulfur concentration was predicted to be one of the major geochemical parameters that had a substantial impact on SOAsR potentials. A combination of DNA stable isotope probing and metagenome binning revealed members of the genera Sulfuricella, Ramlibacter, and Sulfuritalea as sulfur oxidizing As(V)-reducing bacteria (SOAsRB) in mine tailings. Genome mining further expanded the list of potential SOAsRB to diverse phylogenetic lineages such as members associated with Burkholderiaceae and Rhodocyclaceae. Metagenome analysis using multiple tailing samples across southern China confirmed that the putative SOAsRB were the dominant As(V) reducers in these sites. Together, the current findings expand our knowledge regarding the chemolithotrophic As(V) reduction process, which may be harnessed to facilitate future remediation practices in mine tailings.
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Arseniatos , Mineração , Oxirredução , Filogenia , Microbiologia do Solo , Enxofre , Arseniatos/metabolismo , Enxofre/metabolismo , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Ecossistema , Metagenoma , RNA Ribossômico 16S/genética , Poluentes do Solo/metabolismoRESUMO
Near-infrared organic photodetectors possess great application potential in night vision, optical communication, and image sensing, but their development is limited by the lack of narrow bandgap organic semiconductors. A-D-A'-D-A-type molecules, featuring multiple intramolecular charge transfer effects, offer a robust framework for achieving near-infrared light absorption. Herein, we report a novel A-D-A'-D-A-type narrow bandgap electron acceptor named DPPSe-4Cl, which incorporates a selenophene-flanked diketopyrrolopyrrole (Se-DPP) unit as its central A' component. This molecule demonstrates exceptional near-infrared absorption properties with an absorption onset reaching 1120 nm and a low optical bandgap of 1.11 eV, owing to the strong electron-withdrawing ability and quinoidal resonance effect induced by the Se-DPP unit. By implementing a doping compensation strategy assisted by Y6 to reduce the trap density in the photoactive layer, the optimized organic photodetector based on DPPSe-4Cl exhibited efficient spectral response and remarkable sensitivity in the range of 300-1100 nm. Particularly, a specific detectivity surpassing 1012 Jones in the wavelength range of 410-1030 nm is achieved. This work offers a promising approach for developing highly sensitive visible to near-infrared broadband photodetection technology using organic semiconductors.
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Background: Using a toxin-induced lethal acute liver failure (ALF) monkey model, we have recently shown that early peripheral infusion of human umbilical cord mesenchymal stem cells (hUC-MSCs) can alleviate liver damage and improve animal survival by suppressing the activation of circulating monocytes and the subsequent cytokine storm. Here, we explored whether the administration of hUC-MSCs could still improve ALF when the cytokine storm is fully developed. Method: We treated ALF monkeys with peripheral delivery of hUC-MSCs at 48 hr after toxin challenge. Liver indices, histology, imaging, and animal survival were recorded and analyzed. Results: In our cohort study, we conducted and demonstrated that the infusion of hUC-MSCs significantly improved liver histology, effectively controlled inflammatory cytokine storms, and increased survival rates. Additionally, the administration of a higher dose of hUC-MSCs (2 × 107/monkey) yielded superior outcomes compared to a lower dose (1 × 107/monkey). Conclusion: Treatment of hUC-MSCs can significantly improve the pathological and survival outcomes of ALF even when the cytokine storm has been fully developed, indicating a promising clinical solution for ALF.