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In recent decades, Southwest China (SWC) has suffered from frequent super droughts, leading to severe economic losses and ecological degradation. This study investigates the characteristics of super droughts in SWC during 1961–2022, reveals the compounding effect of multiscalar anomalies, and explores the plausible atmospheric circulation mechanisms responsible. The nature of super drought is a compound drought caused by the superposition of extreme drought events across multiple time scales. By contrasting the typical drought cases in 2006 and 2022, the decisive role of multiscalar drought compounding is confirmed. Based on the Comprehensive Multiscalar Index (CMI), multiple super drought events in SWC were identified to be temporally clustered during 2006–2014. Among them, the decadal background of enhanced evaporation and precipitation deficit at long time scales is a necessary condition for shaping the overall pattern of super droughts, while the precipitation and evaporation anomalies at short time scales trigger the outbreak of super droughts, determining the exact timing of occurrence. These events include August–September 2006, November 2009 to May 2010, July–October 2011, April–May 2012, January–April 2013, etc. Statistical results suggest that the contribution of superposed precipitation anomalies to super drought is 2.4 times that of evaporation. As regards the circulation mechanisms affecting multiscalar precipitation, the anomalous spatial patterns at short-term and long-term scales are similar, featuring the cyclonic circulation over the South China Sea and the northeasterly wind anomalies together with the subsidence center over SWC. During 2006–2014, the possible causes for the cross-seasonal persistent precipitation reduction in SWC are the extreme negative phase of the Pacific Decadal Oscillation (PDO) in the North Pacific as well as the pronounced warming of the warm pool in the western Pacific. The key dynamic processes are outlined as follows. On the one hand, the negative PDO phase generates anomalous anticyclonic circulation in the North Pacific, with the northeasterly winds on its southwest flank extending to Southeast Asia, hindering moisture transport into SWC. On the other hand, the warming of the warm pool excites anomalous cyclonic circulation to its northwest, also giving rise to northeasterly wind anomalies over SWC. Meanwhile, the ascending motion over the warm pool region diverges at upper levels with outflows converging aloft over SWC, which further induces compensating downward motion there. The combined effect of the above two remote forcings establishes a climatic background state unfavorable for precipitation over SWC at long time scales, thus constituting a crucial prerequisite for the superimposition of short-term precipitation anomalies to develop into super droughts.

Many endeavors in expressing a heterologous gene in microbial hosts rely on simply placing the gene of interest between a selected pair of promoters and terminator. However, although the expression efficiency could be improved by engineering the host cell, how modifying the expression cassette itself systematically would affect heterologous gene expression remains largely unknown. As the promoter and terminator bear plentiful cis-elements, herein using the Aspergillus nigermannanase with high application value in animal feeds and the eukaryotic filamentous fungus workhorse Trichoderma reeseias a model gene/host, systematic engineering of an expression cassette was investigated to decipher the effect of its mutagenesis on heterologous gene expression. Modifying the promoter, signal peptide, the eukaryotic-specific Kozak sequence, and the 3′-UTR could stepwise improve extracellular mannanase production from 17 U/mL to an ultimate 471 U/mL, representing a 27.7-fold increase in expression. The strategies can be generally applied in improving the production of heterologous proteins in eukaryotic microbial hosts.

Objective: The purpose of this meta-analysis was to estimate the effect of exercise interventions on anxiety and depression in patients with lung cancer through the analysis of randomized controlled trials (RCTs). Methods: Meta-Analyses (PRISMA) guidelines were followed. The meta-analysis was conducted in three databases from inception to May 2022. The investigation focused on assessing the impacts exercise interventions on patients with lung cancer, specifically examing RCTs that reported outcomes related to anxiety and depression. Effect sizes were calculated by standardized mean difference (SMD) with 95% confidence interval (CI)statistics. Additionally, subgroup analyses and sensitivity analyses were conducted. Results: Eleven RCTs involving a total of 987 participants were included in this analysis. The results demonstrated that exercise interventions significantly decreased levels of anxiety (SMD = − 0.65; 95% CI [− 1.79, − 0.52], P= 0.0004) and depression (SMD = − 0.82; 95% CI [− 1.16, − 0.47]; P< 0.01). A subgroup analysis of anxiety, using the HADS scale, showed no heterogeneity (SMD = − 0.23, 95% CI [− 0.45, − 0.02], I2= 0%). Similarly, for depression, the subgroup analysis showed no heterogeneity (SMD = − 0.53, 95% CI [− 0.75, − 0.31]; P< 0.01; I2= 0%). Results of subgroup analyses using the SAS (I2= 90%) and SDS scale (I2= 92%) showed heterogeneity among studies; however, the scale itself was not a source of heterogeneity. Regarding sensitivity analyses for anxiety and depression, they were all statistically robust. Conclusion: In summary, the present meta-analysis suggests that exercise interventions may reduce anxiety and depression levels in patients with lung cancer. The exercise programs included in this trial were associated with less anxiety and depression levels.

Global changes in climate conditions and increasing number of weather-related disasters in the world have elevated the quest for better load restorations in power distribution systems. This paper proposes a distribution system restoration (DSR) model where non-exponential time-dependent cold load pickup (CLPU) characteristics and soft open point operations are simultaneously addressed. We develop a time-dependent CLPU model for attaining a more realistic and secure DSR in which we demonstrate that the traditional delayed exponential model (DEM) for a long outage duration is a special case of the adopted CLPU model. The current soft open point (SOP) models would typically relax the operation constraints without devising any tightening procedures, which might lead to inaccurate or even infeasible SOP states. In this paper, we analyze the reasons traditional SOP constraints would lead to unsecure operations and present a set of novel SOP operation constraints for recovering bindings. Also, we adopt the sequential second order cone programming (SSOCP) algorithm to establish the sequential framework of DSR and solve the proposed model effectively. Our presented case studies discuss the rationality of the proposed DSR model and algorithm.

In contrast to O2, H2O2as the cosubstrate for lytic polysaccharide monooxygenases (LPMOs) exhibits great advantages in industrial settings for cellulose degradation. However, H2O2-driven LPMO reactions from natural microorganisms have not been fully explored and understood. Herein, secretome analysis unraveled the H2O2-driven LPMO reaction in the efficient lignocellulose-degrading fungus Irpex lacteus, including LPMOs with different oxidative regioselectivities and various H2O2-generating oxidases. Biochemical characterization of H2O2-driven LPMO catalysis showed orders of magnitude improvement in catalytic efficiency compared to that of O2-driven LPMO catalysis for cellulose degradation. Significantly, H2O2tolerance of LPMO catalysis in I. lacteuswas an order of magnitude higher than that in other filamentous fungi. In addition, natural reductants, gallic acid, in particular, presented in lignocellulosic biomass could sufficiently maintain LPMO catalytic reactions. Moreover, the H2O2-driven LPMO catalysis exhibited synergy with canonical endoglucanases for efficient cellulose degradation. Taken together, these findings demonstrate the great application potential of the H2O2-driven LPMO catalysis for upgrading cellulase cocktails to further improve cellulose degradation efficiency.

ABSTRACTDue to its bacteriolytic activity, hen egg white lysozyme (HEWL) is widely used in the feed, food, and pharmaceutical industries. However, its application is hindered by low protein expression levels in microbial expression systems. In this work, a novel fusion protein expression strategy was proposed for increasing the expression level of HEWL. First, HEWL, fused with a highly expressed fusion protein partner xylanase XynCDBFV, is expressed in Pichia pastoris. Secondly, a linker including endogenous protease cleavage sites was introduced between two fusion proteins in order to separate them directly during the secretion process. Finally, the results show that the supernatant of XynCDBFV-HEWL has a higher HEWL expression level and activity compared with HEWL only. It should be noted that the expression of HEWL reaches to about 3.5 g/L, and the activity of HEWL against Micrococcus lysodeikticusreaches to 1.50 × 105U/mL in a fed-batch fermentation, which is currently the highest level of recombinant expression of an egg white-derived lysozyme. Taken together, we acquired bioactive HEWL for large-scale recombinant production in Pichia pastoris using a novel fusion protein expression strategy, which could then be used for a variety of applications.

The mycotoxin zearalenone (ZEN) is a secondary metabolite produced mainly by Fusarium species. ZEN poses health hazards both for humans and animals, as a major contaminant in the food and feed industries. Currently, there is no effective technique for degrading ZEN during industrial processes. In this study, we isolated and biochemically characterized a novel lactone hydrolase, ZHD607, isolated from Phialophora americana, cloned, and exogenously expressed in Pichia pastoris. ZHD607 was characterized as a mesophilic lactone hydrolase having a neutral pH and showing optimal activity at 35 °C and pH 8.0. Two mutants, ZHDM1 and I160Y, generated from ZHD607 based on structure and sequence alignment analyses, exhibited 2.9- and 3.4-fold higher activity towards ZEN than did ZHD607. Molecular dynamics simulation revealed diverse mechanisms driving this improved catalytic activity. These findings enrich our knowledge about ZHD enzyme family and represent an important step toward industrialization of ZEN-detoxifying lactone hydrolases.

The strong and inducible cbh1promoter is most widely used to express heterologous proteins, useful in food and feed industries, in Trichoderma reesei. Enhancing its ability to direct transcription provides a general strategy to improve protein production in T. reesei. The cbh1promoter was engineered by replacing eight binding sites of the transcription repressor ACE1 to those of the activators ACE2, Hap2/3/5, and Xyr1. While changing ACE1 to Hap2/3/5-binding sites completely abolished the transcription ability, replacements with ACE2- and Xyr1-binding sites (designated cbh1pA and cbh1pX promoters, respectively) largely improved the promoter transcription efficiency, as reflected by expression of a reporter gene DsRed.The cbh1pA and cbh1pX promoters were applied to improve secretory expression of a codon-optimized mannanase from Aspergillus nigerto 3.6- and 5.0-fold higher, respectively, which has high application potential in feed industry.

Integrating and utilizing resources to seize business opportunities in complex and changing international markets is the key to enhancing the performance of entrepreneurial ventures. This study aimed to examine the impact of entrepreneurship education (EE) on international entrepreneurship performance. We used the resource-based view (RBV) to collect data from 315 international entrepreneurs through a questionnaire survey. The findings indicate that entrepreneurship education positively influences international entrepreneurial performance. Entrepreneurial bricolage (EB) and Entrepreneurial opportunity identification (EOI) are chain mediators of how entrepreneurship education affects international entrepreneurship performance. This study expands the application of resource theory to international entrepreneurship research, enriches the empirical research on entrepreneurship education, and provides new ideas for studying international entrepreneurship performance.

An aspartic protease gene (Bsapa) was cloned from Bisporasp. MEY-1 and expressed in Pichia pastoris. The recombinant BsAPA showed maximal activity at pH 3.0 and 75 °C and remained stable at 70 °C and below, indicating the thermostable nature of BsAPA. However, heat inactivation still limits the application of BsAPA. To further improve its thermostability, an autocatalysis site (L205-F206) in BsAPA was identified and three mutants (F193W, K204P, and A371V) were generated based on the analysis of the structure neighboring the autocatalysis site. These mutants have improved thermostability, and their half-life at 75 °C increased by 0.5-, 0.2-, and 0.3-fold, respectively. A triple-site mutant (F193W/K204P/A371V) was generated, with 1.5-fold increased half-life at 80 and a 10.7 °C increased Tm, compared with those of the wild-type. These results indicate that autocatalysis of aspartic protease reduces enzyme thermostability. Furthermore, site-directed mutagenesis at regions near the autocatalysis site is an efficient approach to improve aspartic protease thermostability.

Objective To investigate the effects of parenteral nutrition (PN) including ω-3 fish-oil emulsion on nutritional state, inflammatory response, and prognosis in patients with acute paraquat poisoning.Methods Patients randomized to receive medium chain triglycerides (MCT)/long chain triglycerides (LCT)-based PN (control group) or MCT/LCT-based PN containing ω-3 fish-oil emulsion (intervention group) were compared for 90-day survival and short-term treatment efficacy.Results Tumour necrosis factor-α levels were significantly lower in the intervention group (n= 101) versus controls (n= 73) on treatment days 4 and 7. Intervention group C-reactive protein (CRP) levels were significantly increased on day 4, decreased to baseline (day 1) levels on day 7, and were significantly lower than baseline on day 10. Control group CRP levels were significantly increased on days 4 and 7 versus baseline, and returned to baseline levels on day 10. On day 7, retinol binding protein had recovered to baseline levels in the intervention group only. Intervention group mortality rate (36.6%) was significantly lower than controls (57.5%). ω-3 fish-oil PN was associated with reduced risk of death (hazard ratio 0.52; 95% confidence interval 0.33, 0.82).Conclusion In patients with acute paraquat poisoning, MCT/LCT with ω-3 fish-oil emulsion PN plus combination treatment advantageously attenuated the inflammatory response, modified the nutritional state, and was associated with significantly improved 90-day survival versus treatment without ω-3 fish oil.

To study the molecular basis for thermophilic β-mannanase of glycoside hydrolase family 5, two β-mannanases, TlMan5A and PMan5A, from Talaromyces leycettanusJCM12802 and Penicilliumsp. WN1 were used as models. The four residues, His112 and Phe113, located near the antiparallel β-sheet at the barrel bottom and Leu375 and Ala408 from loop 7 and loop 8 of PMan5A, were inferred to be key thermostability contributors through module substitution, truncation, and site-directed mutagenesis. The effects of these four residues on the thermal properties followed the order H112Y > A408P > L375H > F113Y and were strongly synergetic. These results were interpreted structurally using molecular dynamics (MD) simulations, which showed that improved hydrophobic interactions in the inner wall of the β-barrel and the rigidity of loop 8 were caused by the outside domain of the barrel bottom and proline, respectively. The TIM barrel bottom and four specific residues responsible for the thermostability of GH5 β-mannanases were elucidated.

Colorectal cancer is one of the 3 most common cancers worldwide. In this study, a weighted network-based analysis method was proposed to explore the pathological mechanisms and prognostic targets of rectal adenocarcinoma (READ) at the deoxyribonucleic acid (DNA) methylation level.In this study, we downloaded clinical information and DNA methylation data from The Cancer Genome Atlas database. Differentially methylated gene analysis was used to identify the differential methylated genes in READ. Canonical correlation analysis was used to construct the weighted gene regulatory network for READ. Multilevel analysis and association analyses between gene modules and clinical information were used to mine key modules related to tumor metastasis evaluation. Genetic significance analysis was used to identify methylation sites in key modules. Finally, the importance of these methylation sites was confirmed using survival analysis.DNA methylation datasets from 90 cancer tissue samples and 6 paracancerous tissue samples were selected. A weighted gene regulatory network was constructed, and a multilevel algorithm was used to divide the gene co-expression network into 20 modules. From gene ontology enrichment analysis, characteristic M was related to biological processes such as the chemotaxis of fibroblast growth factors and the activation and regulation of immune cells etc and characteristic N was associated with the regulation of cytoskeleton formation, mainly microtubules and flagella, regulation of synapses, and regulation of cell mitosis. Based on the results of survival analysis, 7 key methylation sites were found closely correlated to the survival rate of READ, such as cg04441191 (microtubule-associated protein 4 [MAP4]), cg05658717 (KSR2), cg09622330 (GRIN2A), cg10698404 (YWHAG), cg17047993 (SPAG9), cg24504843 (CEP135), and cg24531267 (CEP250). Mutational and transcriptomic level studies revealed significant differences in DNA methylation, single nucleotide polymorphism, and transcript levels between YWHAG and MAP4 in normal tissues compared to tumor tissues, and differential expression of the 2 proteins in immunohistochemistry. Therefore, potential targeting drugs were screened for these 2 proteins for molecular docking, and artenimol was found to bind to MAP4 protein and 27-hydroxycholesterol to YWHAG.Our study found that key methylation sites played an important role in tumor metastasis and were associated with the prognosis of READ. Mutations and methylation may jointly regulate the transcription and translation of related genes, which in turn affect cancer progression. This may provide some new potential therapeutic targets and thoughts for the prognosis of READ.

Biocatalysts are increasingly employed as more efficient and environmentally safer alternatives to traditional chemical catalysts in the manufacturing of fine chemicals. This is driven by advances in recombinant DNA technology, protein engineering and bioinformatics, all of which are critical in the discovery, tailoring and optimization of enzymes for industrial processes. In this article we review these key technological innovations, as well as highlight the strategic application of these tools in the development of biocatalysts in the production of advanced pharmaceutical intermediates.

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Thermostable enzymes have many advantages for industrial applications. Therefore, in this study, computer-aided design technology was used to improve the thermostability of a highly active endo-polygalacturonase from Talaromyces leycettanusJCM12802 at an optimal temperature of 70 °C. The melting temperature and specific activity of the obtained mutant T316C/G344C were increased by 10 °C and 36.5%, respectively, compared with the wild-type enzyme. The crystal structure of the T316C/G344C mutant showed no formation of a disulfide bond between the introduced cysteines, indicating a different mechanism than the conventional mechanism underlying improved enzyme thermostability. The cysteine substitutions directly formed a new alkyl hydrophobic interaction and caused conformational changes in the side chains of the adjacent residues Asn315 and Thr343, which in turn caused a local reconstruction of hydrogen bonds. This method greatly improved the thermostability of the enzyme without affecting its activity; thus, our findings are of great significance for both theoretical research and practical applications.

Thermostability is a key property of industrial enzymes. Endo-polygalacturonases of the glycoside hydrolase family 28 have many practical applications, but only few of their structures have been determined, and the reasons for their stability remain unclear. We identified and characterized the Talaromyces leycettanusJCM12802 endo-polygalacturonase TlPGA, which differs from other GH28 family members because of its high catalytic activity, with an optimum temperature of 70 °C. Distinctive features were revealed by comparison of thermophilic TlPGA and all known structures of fungal endo-polygalacturonases, including a relatively large exposed polar accessible surface area in thermophilic TlPGA. By mutating potentially important residues in thermophilic TlPGA, we identified Thr284 as a critical residue. Mutant T284A was comparable to thermophilic TlPGA in melting temperature but exhibited a significantly lower half-life and half-inactivation temperature, implicating residue Thr284 in the kinetic stability of thermophilic TlPGA. Structure analysis of thermophilic TlPGA and mutant T284A revealed that a carbon–oxygen hydrogen bond between the hydroxyl group of Thr284 and the Cα atom of Gln255, and the stable conformation adopted by Gln255, contribute to its kinetic stability. Our results clarify the mechanism underlying the kinetic stability of GH28 endo-polygalacturonases and may guide the engineering of thermostable enzymes for industrial applications.