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Recent advances in doped organic field-effect transistors: mechanism, influencing factors, materials, and development directions.

We summarize the recent progress in the application of high-performance STOFETs achieved by developing stretchable channel materials and processing techniques.

Background: Evidence of direct-acting antiviral (DAA) treatment for refractory chronic hepatitis C (CHC) patients was limited. We aimed to evaluate the effectiveness and safety of Sofosbuvir/Velpatasvir (SOF/VEL) plus Ribavirin (RBV) in cirrhotic patients with hepatitis C virus genotype 3 (GT3) with or without HIV or HBV coinfection. Methods: From June 2019 to December 2022, CHC GT3 patients who received SOF/VEL plus RBV (dosage of RBV depended on weight) for 12 weeks were enrolled. Liver cirrhosis was diagnosed by clinical presentation . The primary endpoint was sustained virologic response at 12 weeks off-therapy (SVR12). Adverse events (AE)were assessed during treatment. Results:In total, 285 treatment-naive patients were recruited at the Kunming Third People’s Hospital. Mean age was 48.18±8.27 years-old and 74.04% (211/285) were male. All patients had GT3 HCV infection including 44 patients with GT3a and 241 patients with hepatitis C virus genotype 3b (GT3b) . Among these patients, 39 with HCV/HIV,10 with HBV/HCV, and 1 with HBV/HCV/HIV coinfection. All patients had liver cirrhosis, and 46.67% (133/285) of patients had compensated cirrhosis (CC), while 53.33% (152/285) of patients had decompensated cirrhosis (DCC). 98.95% (282/285) patients achieved SVR12 with SOF/VEL plus RBV treatment for 12 weeks, including 97.72% (43/44) in GT3a and 99.17% (239/241) in GT3b. According to the condition for 285 patients with liver cirrhosis, the SVR12 rate in the CC group was : 99.25% (132/133), the SVR12 rate in the DCC group was: 98.68% (150/152). After 12 weeks of treatment, the APRI score and FIB-4 score in CC group and DCC group were improved, and the improvement in the compensated cirrhosis group was better than that in decompensated cirrhosis group (PAPRI=0.001, PFIB-4=0.001). Mean ALT (from 74±27.23U/L to 39.31±12.22U/L, pConclusion： SOF/VEL combined with RBV for cirrhotic GT3 hepatitis C patients all obtained high SVR12 (>95%), improved liver function during treatment, and for cirrhotic GT3 hepatitis C patients treatment with SOF/VEL combined with RBV is recommended as early as possible.

Reduced glutathione (GSH) is an antioxidant in plants and is one of the important ways for plants to combat low-temperature stress. In this paper, Eriobotrya japonica Lindl. cv. Zaozhong No. 6 seedlings were used to study the effects of exogenous 5-aminolevulinic acid (ALA) application on glutathione synthesis and cyclic metabolism of loquat seedlings under low-temperature stress and to explore the regulatory mechanism of ALA on loquat cold tolerance. The results showed that ALA treatment could increase the content of GSH and the reduced glutathione/oxidized glutathione (GSH/GSSG) ratio in loquat leaf slices under low-temperature stress; reduce the electrolyte leakage rate and GSSG, H2O2 and MDA contents in leaf tissues; and alleviate the peroxidation damage caused by low temperature. ALA treatment increased the activity of γ-glutamine synthetase (γ-ECS) in loquat leaf slices under low-temperature stress and promoted the biosynthesis of reduced glutathione, thereby increasing the GSH content in leaf tissues. On the other hand, ALA treatment could also improve the activities of glutathione reductase (GR), glutathione S-transferase (GST) and glutathione peroxidase (GPX) and promote the cyclic regeneration of GSH, accordingly maintaining a high GSH/GSSG ratio, promoting the removal of reactive oxygen species (ROS), and enhancing the antioxidant capacity of leaves. The regulatory effect of ALA on enhancing the antioxidant capacity of loquat seedlings under low-temperature stress can be inhibited by L-buthionine-sulfoximine (BSO, GSH biosynthesis inhibitor). The results showed that ALA improved the antioxidant capacity of loquat seedlings under low-temperature stress, and GSH was involved in the regulation of the antioxidant effect of ALA on loquat seedlings under low-temperature stress.

The availability of large-scale genomic data resources makes it very convenient to mine and analyze genes that are related to important agricultural traits in rice. Pan-genomes have been constructed to provide insight into the genome diversity and functionality of different plants, which can be used in genome-assisted crop improvement. Thus, a pan-genome comprising all genetic elements is crucial for comprehensive variation study among the heat-resistant and -susceptible rice varieties. In this study, a rice pan-genome was firstly constructed by using 45 heat-tolerant and 15 heat-sensitive rice varieties. A total of 38,998 pan-genome genes were identified, including 37,859 genes in the reference and 1141 in the non-reference contigs. Genomic variation analysis demonstrated that a total of 76,435 SNPs were detected and identified as the heat-tolerance-related SNPs, which were specifically present in the highly heat-resistant rice cultivars and located in the genic regions or within 2 kbp upstream and downstream of the genes. Meanwhile, 3214 upregulated and 2212 downregulated genes with heat stress tolerance-related SNPs were detected in one or multiple RNA-seq datasets of rice under heat stress, among which 24 were located in the non-reference contigs of the rice pan-genome. We then mapped the DEGs with heat stress tolerance-related SNPs to the heat stress-resistant QTL regions. A total of 1677 DEGs, including 990 upregulated and 687 downregulated genes, were mapped to the 46 heat stress-resistant QTL regions, in which 2 upregulated genes with heat stress tolerance-related SNPs were identified in the non-reference sequences. This pan-genome resource is an important step towards the effective and efficient genetic improvement of heat stress resistance in rice to help meet the rapidly growing needs for improved rice productivity under different environmental stresses. These findings provide further insight into the functional validation of a number of non-reference genes and, especially, the two genes identified in the heat stress-resistant QTLs in rice.

Structural engineering of the light-harvesting dyes employed in DSSCs (dye-sensitized solar cells) with a systematic choice of the electron-donating and -accepting groups as well as the π-bridge allows the (photo)physical properties of dyes to match the criteria needed for improving the DSSC efficiency. Herein, we report an effective approach of molecular engineering of DSSC sensitizers, aiming to gain insights on the configurational impact of the fluorenyl unit on the optoelectronic properties and photovoltaic performance of DSSCs. Five new organic dyes (GZ116, GZ126, GZ129, MA1116, and MA1118) with a D-A-π-A framework integrated with a fluorenyl moiety were designed and synthesized for DSSCs. The fluorenyl unit is configured as part of the π-spacer for the GZ series, whereas it connected on the electron-deficient quinoxaline motif for the MA series. The devices fabricated from the MA1116 sensitizer produced the best performance under standard AM 1.5 G solar conditions as well as dim-light (300-6000 lx) illumination. The devices fabricated from MA1116 displayed a PCE of 8.68% (Jsc = 15.00 mA cm-2, Voc = 0.82 V, and FF = 0.71) under 1 sun and 26.81% (Jsc = 0.93 mA cm-2, Voc = 0.68 V, and FF = 0.76) under 6000 lx illumination. The device efficiency based on dye MA1116 under 1 sun outperformed that based on the standard N719 dye, whereas a comparable performance between devices based on MA1116 and N719 was achieved under dim-light conditions. A combination of enhancing the charge separation, suppressing dye aggregation, and providing better insulation that prevents the oxidized redox mediator from approaching the TiO2 surface all contribute to the superior performance of DSSCs fabricated based on these light-harvesting dyes. The judicious integration of the fluorenyl unit in a D-A-π-A-based DSSC would be a promising strategy to boost the device performance.

Grafting of organic groups on the surface of metal-oxide clusters greatly enhances the Li+ ion capacity. Triply organo-substituted polyoxometalates (RN-POMs) display an excellent Li+ ion capacity (...

In light of global environmental crises and the need for sustainable development, the fields of public health and environmental sciences have become increasingly interrelated. Both fields require interdisciplinary thinking and global solutions, which is largely directed by scientific progress documented in peer-reviewed journals. Journal editors play a critical role in coordinating and shaping what is accepted as scientific knowledge. Previous research has demonstrated a lack of diversity in the gender and geographic representation of editors across scientific disciplines. This study aimed to explore the diversity of journal editorial boards publishing in environmental science and public health. The Clarivate Journal Citation Reports database was used to identify journals classified as Public, Environmental, and Occupational (PEO) Health, Environmental Studies, or Environmental Sciences. Current EB members were identified from each journal’s publicly available website between 1 March and 31 May 2021. Individuals’ names, editorial board roles, institutional affiliations, geographic locations (city, country), and inferred gender were collected. Binomial 95% confidence intervals were calculated for the proportions of interest. Pearson correlations with false discovery rate adjustment were used to assess the correlation between journal-based indicators and editorial board characteristics. Linear regression and logistic regression models were fitted to further assess the relationship between gender presence, low- and middle-income country (LMIC) presence and several journal and editor-based indicators. After identifying 628 unique journals and excluding discontinued or unavailable journals, 615 journal editorial boards were included. In-depth analysis was conducted on 591 journals with complete gender and geographic data for their 27,772 editors. Overall, the majority of editors were men (65.9%), followed by women (32.9%) and non-binary/other gender minorities (0.05%). 75.5% journal editorial boards (n = 446) were composed of a majority of men (>55% men), whilst only 13.2% (n = 78) demonstrated gender parity (between 45–55% women/gender minorities). Journals categorized as PEO Health had the most gender diversity. Furthermore, 84% of editors (n = 23,280) were based in high-income countries and only 2.5% of journals (n = 15) demonstrated economic parity in their editorial boards (between 45–55% editors from LMICs). Geographically, the majority of editors’ institutions were based in the United Nations (UN) Western Europe and Other region (76.9%), with 35.2% of editors (n = 9,761) coming solely from the United States and 8.6% (n = 2,373) solely from the United Kingdom. None of the editors-in-chief and only 27 editors in total were women based in low-income countries. Through the examination of journal editorial boards, this study exposes the glaring lack of diversity in editorial boards in environmental science and public health, explores the power dynamics affecting the creation and dissemination of knowledge, and proposes concrete actions to remedy these structural inequities in order to inform more equitable, just and impactful knowledge creation. Gates Cambridge Scholarship Bill and Melinda Gates Foundation

Three new hole-transporting materials (HTMs), composed of N3,N6-bis(di-4-anisylamino)-9H-carbazole and anthracene moieties, have been developed for perovskite solar cell (PSC) application. Two of t...

Histidine protein kinases (HKs) are prevalent prokaryotic sensor kinases that are central to phosphotransfer in two-component signal transduction systems, regulating phosphorylation of response regulator proteins that determine the output responses. HKs typically exist as dimers and can potentially autophosphorylate at each conserved histidine residue in the individual protomers, leading to diphosphorylation. However, analyses of HK phosphorylation in biochemical assays in vitro suggest negative cooperativity, whereby phosphorylation in one protomer of the dimer inhibits phosphorylation in the second protomer, leading to ∼50% phosphorylation of the available sites in dimers. This negative cooperativity is often correlated with an asymmetric domain arrangement, a common structural characteristic of autophosphorylation states in many HK structures. In this study, we engineered covalent dimers of the cytoplasmic domains of Escherichia coli CpxA, enabling us to quantify individual species: unphosphorylated, monophosphorylated, and diphosphorylated dimers. Together with mathematical modeling, we unambiguously demonstrate no cooperativity in autophosphorylation of CpxA despite its asymmetric structures, indicating that these asymmetric domain arrangements are not linked to negative cooperativity and hemiphosphorylation. Furthermore, the modeling indicated that many parameters, most notably minor amounts of ADP generated during autophosphorylation reactions or present in ATP preparations, can produce ∼50% total phosphorylation that may be mistakenly attributed to negative cooperativity. This study also establishes that the engineered covalent heterodimer provides a robust experimental system for investigating cooperativity in HK autophosphorylation and offers a useful tool for testing how symmetric or asymmetric structural features influence HK functions.

Undergraduate students in STEM fields often lack writing experience as their majors usually do not require intensive writing courses. Therefore, many STEM students do not engage in writing as much as students in humanities and social sciences. In order to better understand and help STEM students writing, it is important to investigate STEM students’ perceptions regarding their writing practices in the university. The research was conducted in a research university located in Central Asia, Kazakhstan. Two qualitative research methods were used in the study, namely, qualitative interview and paper observation. Five students from different majors in the STEM fields were interviewed, and five of their writing assignments were collected and analyzed. Findings demonstrated that students in the chosen university have similar struggles and opinions about writing as revealed in the literature. STEM students understand that writing is significant; however, due to the lack of experience, they do not always see the importance of writing in their own majors. It was also found that, in terms of building their perceptions, the roles of STEM faculties and the University Writing Center are crucial factors. They can contribute to students’ writing in both positive and negative ways. The implications of the research can be beneficial for constructing and adjusting policies and regulations in the university curriculum to help STEM students build more positive perceptions about writing.

The relevant provisions of the mortar rebound method in the national code GB/T50315 “Technical Standards for site testing of masonry engineering” is only focus on mortar rebound method of sinter bricks, but whether the rebound curve of sintered brick mortar can be used for non-sintered brick mortar is uncertain. Therefore, the rebound curve of non-sintered brick mortar needs to be further studied. The mortar rebound method of sintered bricks is used as a model for the research process for mortar rebound method of other blocks, and the mortar of three widely used blocks of concrete products in masonry structures is selected as the research object. In the end, the mortar rebound curves for mortars of three widely used blocks are obtained through relevant tests, the results showed that the mortar rebound curves of sintered brick and non-sintered brick are completely different, thus broadening the application area of the mortar rebound method.

Site-specifically labeling proteins with multiple dyes or molecular moieties is an important yet non-trivial task for many research, such as when using Föster resonance energy transfer (FRET) to study dynamics of protein conformational change. Many strategies have been devised, but usually done on a case-by-case basis. Expanded genetic code provided a general platform to incorporate non-canonical amino acids (ncAA), which can also enable multiple site-specific labeling, but it’s technically complicated and not suitable for some applications. Here we present a streamlined method that could enable dual site-specific protein labeling by using a tryptophan auxotroph of Escherichia coli to incorporate a naturally found tryptophan analog, 5-hydroxytryptophan into a recombinant protein. As a demonstration, we incorporated 5-hydroxytryptophan into E. coli release factor 1 (RF1), a protein known to possess two different conformations, and site-specifically attached two different fluorophores, one on 5-hydroxytryptophan and another on a cysteine residue. This method is simple, generally applicable, efficient, and can serve as an alternative way for researchers who want to install an additional labeling site in their proteins.

Studies of transcription regulation are often focused on binding of transcription factors (TFs) to a small number of promoters of interest. It is often assumed that TFs are in great excess to their binding sites (TFBSs) and competition for TFs between DNA sites is seldom considered. With increasing evidence that TFBSs are exceedingly abundant for many TFs and significant variations in TF and TFBS numbers occur during growth, the interplay between a TF and all TFBSs should not be ignored. Here, we use additional decoy DNA sites to quantitatively analyze how the relative abundance of a TF to its TFBSs impacts the steady-state level and onset time of gene expression for the auto-activated Escherichia coli PhoB response regulator. We show that increasing numbers of decoy sites progressively delayed transcription activation and lowered promoter activities. Perturbation of transcription regulation by additional TFBSs did not require extreme numbers of decoys, suggesting that PhoB is approximately at capacity for its DNA sites. Addition of decoys also converted a graded response to a bi-modal response. We developed a binding competition model that captures the major features of experimental observations, providing a quantitative framework to assess how variations in TFs and TFBSs influence transcriptional responses.