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A freezing method is usually employed in the construction of metro links. Unconfined compressive strength (UCS) is a pivotal mechanical parameter in freezing design. Due to the limitations of indoor experiments and the complexity of influencing factors, the applicability of empirical strength formulas is poor. This study predicts the strength of frozen soil with different particle size distributions based on the highly integrated XGBoost algorithm. Compared with other empirical formula methods, the accuracy is high. Through the analysis of Pearson's correlation coefficient results, further analysis is needed on the nonlinear correlation between the temperature, the strain rate, and the unconfined compressive strength of frozen soil. The results indicated a strong negative correlation between temperature and unconfined compressive strength; the strength initially increased at a faster rate, slowed down during the intermediate phase, and again increased at a faster rate toward the end. There was a positive correlation between the strain rate and the unconfined compressive strength, with the strength exhibiting varying sensitivities to different sizes of strain rates. When the strain rate was relatively small, the strength increased slightly; as the strain rate increased, the strength increased more significantly. Different soils showed similar trends, but differences in the particle size distribution resulted in variations in the final strength. This study can provide a scientific basis for predicting the strength of soil bodies in the freeze–thaw construction of subway connection tunnels. [ABSTRACT FROM AUTHOR]

At present, the development and usage of degradable plastics instead of traditional plastics is an effective way to solve the pollution of marine microplastics. Poly (butylene adipate-co-terephthalate) (PBAT) is known as one of the most promising biodegradable materials. Nevertheless, the degradation rate of PBAT in water environment is slow. In this work, we successfully prepared four kinds of high molecular weight polyester copolyesters (PBATGA) via quaternary copolymerization. The results showed that the intrinsic viscosity of PBATGA copolymers ranged from 0.74 to 1.01 dL/g with a glycolic acid content of 0–40%. PBATGA copolymers had excellent flexibility and thermal stability. The tensile strength was 5~40 MPa, the elongation at break was greater than 460%, especially the elongation at break of PBATGA10 at 1235%, and the thermal decomposition temperature of PBATGA copolyesters was higher than 375 °C. It was found that PBATGA copolyester had a faster hydrolysis rate than PBAT, and the weight loss of PBATGA copolymers showed a tendency of pH = 12 > Lipase ≈ pH = 7 > pH = 2. The quaternary polymerization of PBAT will have the advantage of achieving industrialization, unlike the previous polymerization process. In addition, the polymerization of PBATGA copolyesters not only utilizes the by-products of the coal chemical industry, but also it can be promising in the production of biodegradable packaging to reduce marine plastic pollution. [ABSTRACT FROM AUTHOR]

While the Food and Drug Administration's black-box warnings caution against concurrent opioid and benzodiazepine (OPI–BZD) use, there is little guidance on how to deprescribe these medications. This scoping review analyzes the available opioid and/or benzodiazepine deprescribing strategies from the PubMed, EMBASE, Web of Science, Scopus, and Cochrane Library databases (01/1995–08/2020) and the gray literature. We identified 39 original research studies (opioids: n = 5, benzodiazepines: n = 31, concurrent use: n = 3) and 26 guidelines (opioids: n = 16, benzodiazepines: n = 11, concurrent use: n = 0). Among the three studies deprescribing concurrent use (success rates of 21–100%), two evaluated a 3-week rehabilitation program, and one assessed a 24-week primary care intervention for veterans. Initial opioid dose deprescribing rates ranged from (1) 10–20%/weekday followed by 2.5–10%/weekday over three weeks to (2) 10–25%/1–4 weeks. Initial benzodiazepine dose deprescribing rates ranged from (1) patient-specific reductions over three weeks to (2) 50% dose reduction for 2–4 weeks, followed by 2–8 weeks of dose maintenance and then a 25% reduction biweekly. Among the 26 guidelines identified, 22 highlighted the risks of co-prescribing OPI–BZD, and 4 provided conflicting recommendations on the OPI–BZD deprescribing sequence. Thirty-five states' websites provided resources for opioid deprescription and three states' websites had benzodiazepine deprescribing recommendations. Further studies are needed to better guide OPI–BZD deprescription. [ABSTRACT FROM AUTHOR]

The problems of regional resource shortage, fragile ecological environment and unbalanced social development are becoming increasingly serious. There is an urgent need for rational evaluation and planning of resources and the environment. This paper presents a fuzzy comprehensive evaluation method combined with Analytic Hierarchy Process (AHP) and shortcoming element evaluation to analyze the resource and environmental bearing capacity of a certain region. The proposed model was verified by backing data analysis from a karst landscape region in southwest China. Short board element analysis was employed for further study. The results show that (a) the calculation results of the evaluation system used in this paper are consistent with the actual situation. The method can be effectively used in the field of resource and environmental carrying capacity evaluation. (b) The environmental carrying capacity is the largest in this region, followed by the resource carrying capacity, and the socio-economic carrying capacity is the smallest. (c) The region has a sufficient environmental carrying capacity on the whole, the resource conditions are weak and the socio-economic development is backward. The analysis of the evaluation results provides a scientific basis for the rational use of resources, territorial spatial planning, sustainable socio-economic development and ecological environmental protection strategies in karst mountainous areas. [ABSTRACT FROM AUTHOR]

In this paper, we consider the nonlinear impulsive generalized fractional differential equations with (p , q) -Laplacian operator for 1 < p ≤ q < ∞ , in which the nonlinearity f contains two fractional derivatives with respect to another function. Since the complexity of the nonlinear term and the impulses exist in generalized fractional calculus, it is difficult to find the corresponding variational functional of the problem. The existence of nontrivial solutions for the problem is established by the mountain pass theorem and iterative technique under some appropriate assumptions. Furthermore, our main result is demonstrated by an illustrative example to show its feasibility and effectiveness. Due to the employment of a generalized fractional operator, our results extend some existing research findings. [ABSTRACT FROM AUTHOR]

The main problem of manufacturing with traditional biodegradable plastics is that it is more expensive than manufacturing with polymers derived from petroleum, and the application scope is currently limited due to poor comprehensive performance. In this study, a novel biodegradable poly(butylene adipic acid/terephthalate-co-glycolic acid) (PBATGA) copolyester with 25–60% glycolic acid units was successfully synthesized by esterification and polycondensation using cheap coal chemical byproduct methyl glycolate instead of expensive glycolic acid. The structure of the copolyester was characterized by ATR-FTIR, 1H NMR, DSC, and XRD; and its barrier property, water contact angle, heat resistance, and mechanical properties were tested. According to the experiment result, the PBATGA copolyesters showed improved oxygen (O2) and water vapor barrier character, and better hydrophilicity when compared with PBAT. The crystallization peaks of PBATGAs were elevated from 64 °C to 77 °C when the content of the GA unit was 25 mol %, meanwhile, the elongation at the break of PBATGA25 was more than 1300%. These results indicate that PBATGA copolyesters have good potentiality in high O2 and water vapor barrier and degradable packaging material. [ABSTRACT FROM AUTHOR]

At 15:48 on 24 July 2021, a fire accident occurred in Changchun City, Jilin Province, China, resulting in 15 deaths and 25 injuries. After the accident happened, Jilin Province comprehensively organised an emergency rescue, saving more than 100 trapped people. Given the dangers posed by these events, it is recommended that we must strengthen our risk awareness. Combined with the general background and scene of the fire, in this study, we analysed the causes of the accident and described the on-site rescue actions. The direct cause of the accident was an arc fault, and the indirect cause was the dereliction of duty in the laying and installation of the circuit and the subsequent fire supervision. From our case analysis of electrical fires in public buildings, we found that electrical failure, human factors (illegal operation), ageing and short circuits of wires, poor contact of wires, and ignition of other combustibles by electrical appliances are the main factors causing electrical fire accidents in public buildings. To avoid serious fire accidents caused by arc faults, we proposed suggestions to reduce or prevent electric fire accidents caused by arc faults. [ABSTRACT FROM AUTHOR]

This study presents an evaluation of climate and land-use changes induced impacts on water resources of Multan City, Pakistan. Statistical Down Scaling Model (SDSM) and Geographical Information System (GIS) are used for climate change scenario and spatial analyses. Hydrologic Engineering Center's Hydraulic Modeling System (HEC-HMS) model is used for rainfall-runoff simulation. The investigated results show significant changes in climatological parameters, i.e., an increase in temperature and decrease in precipitation over the last 40 years, and a significant urban expansion is also observed from 2000 to 2020. The increase in temperature and urbanization has reduced the infiltration rate into the soil and increased the runoff flows. The HEC-HMS results indicate that surface runoff gradually increased over the last two decades. Consequently, the depth of the water table in the shallow aquifer has declined by about 0.3 m/year. Projected climate indices stipulate that groundwater depletion will occur in the future. Arsenic levels have exceeded the permissible limit owing to unplanned urban expansion and open dumping of industrial effluents. The results can help an efficient water resources management in Multan. [ABSTRACT FROM AUTHOR]

Rice is frequently affected by cold weather at high altitudes in temperate and subtropical regions. With the popularity of direct seeding, a better understanding of the genetic mechanisms regulating cold tolerance will enable breeders to develop varieties with strong low temperature germinability (LTG). In this study, six indices including low temperature germination percentage (LTGP), relative germination percentage (RGP), relative plumule length (RPL), plumule length after 6-day recovery (PLR), plumule length recovery rate (PLRR) and recovery ability of plumule length after cold stress (RAPL) were measured to assess LTG, and carried out a genome-wide association study (GWAS) to identify QTL and candidate genes related to LTG by using a natural population comprising 211 rice accessions. A total of 18 QTL including two for LTGP, three for RGP, five for PLR, four for PLRR, two for RPL and two for RAPL were uncovered on 12 chromosome regions located in chromosome 1, 2, 4, 5, 6, 9, 10 and 12. On chromosome 2, qLTGP2 and qRGP2 were co-localized at 3.3 Mb, and qPLR2 and qPLRR2 were co-localized at 5.5 Mb; qLTGP5, qPLR5 and qPLR5 were co-localized at 27.8 Mb on chromosome 5; qPLR6 and qPLRR6 were co-localized at 5.7 Mb on chromosome 6; and qPLR12 and qPLRR12 were co-localized at 23.5 Mb on chromosome 12. These results indicated that some LTG-related traits may share the same genetic pathway. For the 18 LTG-related QTL, seven QTL (qLTGP2, qRGP2, qPLR2, qPLRR2, qLTGP5, qPLR5 and qPLR5) were reported for the first time. According to candidate gene analysis, fourteen genes from five QTL (qLTGP2, qPLR2, qLTGP5, qRAPL10 and qPLR12) were considered as candidate genes and will be further functionally validated in subsequent experiments. QTL with superior candidate genes identified in this study will be useful in improving cold tolerance in rice cultivars. The rice varieties with strong LTG identified in this study will enrich the resources of rice cultivation project. [ABSTRACT FROM AUTHOR]

The application of heterosis during plant breeding increases rice grain yield. However, there have been limited studies on heterosis during rice grain development during the grain-filling stage; therefore, the genetic basis of heterosis for grain development during the grain-filling stage should be highly valued. In this study, a hybrid combination with the super hybrid rice WFYT025 was used to perform a transcriptomic dynamic analysis in grains at the beginning and middle grain-filling stages. A total of 1556 and 1507 transcripts that were differentially expressed between WFYT025 and its parents (DGHP) were identified at 1-day post-anthesis (DPA) and at 10 DPA, respectively. The analysis of the genetic effects of heterosis showed that the over-dominant effect (66.90% and 55.87%) was the main mode of action during grain development. The KEGG pathway and GO analysis of the DGHP indicated that the gibberellin biosynthetic, starch metabolic, and diterpenoid biosynthetic signaling pathways may be associated with heterosis during grain development. To further explore the candidate genes for grain development heterosis, a recombinant inbred line (RILs) population with a high-density genetic map of 2578 bin markers was constructed by crossing the parents of WFYT025, and nine stable QTLs for grain weight-related traits were identified. By comparing the DGHP with 20 QTLs, LOC_Os02g28820, LOC_Os02g32580, LOC_Os04g25440, and LOC_Os12g04980 were identified as grain development heterosis-related candidate genes. These findings provide resources for the study of heterosis during the grain development of super hybrid rice and provide valuable theoretical references for the cloning and functional analysis of heterosis-related genes. [ABSTRACT FROM AUTHOR]

Background: The novel coronavirus that has triggered the present COVID-19 pandemic continues to spread globally, resulting in widespread morbidity and mortality. Patients with cancer remain one of the most vulnerable subsets of the population to the disease. This study examined the effects of the pandemic on cancer patients' treatment, psychology, knowledge, attitudes, and practices., Methods: A survey was emailed to 9861 patients at a cancer centre in Toronto, Canada. Descriptive results were summarized. Qualitative feedback was coded and summarized. Regression modelling was used to explore factors associated with patient psychological well-being, knowledge, attitudes, and practices., Results: A total of 1760 surveys were completed, with a response rate of 17.8%. Most participants did not experience any pandemic-related treatment delays, and vaccination rates were high. Participants who identified themselves as non-white (OR 3.30, CI: 1.30-5.30; p ≤ 0.001), and those who referred to journal articles for information ( p = 0.002) reported higher psychological impact scores. There were no significant predictors of whether participants would use personal protective equipment when leaving their homes or whether they would go to crowded places., Discussion: This study provides another snapshot of cancer patients perceptions and needs during the COVID-19 pandemic.