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Drug discovery is costly and time consuming, and modern drug discovery endeavors are progressively reliant on computational methodologies, aiming to mitigate temporal and financial expenditures associated with the process. In particular, the time required for vaccine and drug discovery is prolonged during emergency situations such as the coronavirus 2019 pandemic. Recently, the performance of deep learning methods in drug virtual screening has been particularly prominent. It has become a concern for researchers how to summarize the existing deep learning in drug virtual screening, select different models for different drug screening problems, exploit the advantages of deep learning models, and further improve the capability of deep learning in drug virtual screening. This review first introduces the basic concepts of drug virtual screening, common datasets, and data representation methods. Then, large numbers of common deep learning methods for drug virtual screening are compared and analyzed. In addition, a dataset of different sizes is constructed independently to evaluate the performance of each deep learning model for the difficult problem of large-scale ligand virtual screening. Finally, the existing challenges and future directions in the field of virtual screening are presented.

Abstract Background Stroke-associated pneumonia (SAP) and gastrointestinal bleeding (GIB) are common medical complications after stroke. The previous study suggested a strong association between SAP and GIB after stroke. However, little is known about the time sequence of SAP and GIB. In the present study, we aimed to verify the association and clarify the temporal sequence of SAP and GIB after ischemic stroke. Methods Patients with ischemic stroke from in-hospital Medical Complication after Acute Stroke study were analyzed. Data on occurrences of SAP and GIB during hospitalization and the intervals from stroke onset to diagnosis of SAP and GIB were collected. Multiple logistic regression was used to evaluate the association between SAP and GIB. Kruskal-Wallis test was used to compare the time intervals from stroke onset to diagnosis of SAP and GIB. Results A total of 1129 patients with ischemic stroke were included. The median length of hospitalization was 14 days. Overall, 86 patients (7.6%; 95% CI, 6.1-9.2%) developed SAP and 47 patients (4.3%; 95% CI, 3.0-5.3%) developed GIB during hospitalization. After adjusting potential confounders, SAP was significantly associated with the development of GIB after ischemic stroke (OR = 5.13; 95% CI, 2.02-13.00; P

Purposes Increasing the permeability of coal reservoirs is a key technology to improve the recovery rate of coalbed methane, and in-situ thermal injection mining is an effective method to enhance coalbed methane production. Methods In order to explore the change rule of coal reservoir permeability under the coupling of heat, fluid, and solid, pyrolysis seepage experiments of anthracite with different burial depths and temperatures were conducted, and theoretical analysis and research were conducted on the experimental results. Findings The results showed that: 1) Under three-dimensional effective stress, the permeability of pyrolysis anthracite varies with temperature and pore pressure in a "V" shape, with a significant rebound phenomenon, which decreases with the increase of burial depth. When the pore pressure is less than the critical pore pressure and the temperature is lower than 70 ℃, the permeability of the coal body mainly depends on the slippage effect. When the pore pressure is greater than the critical pore pressure and the temperature is higher than 70 ℃, the permeability mainly depends on thermal expansion and the opening degree of pore pressure on the fracture, and the impact of thermal stimulation on the permeability is much greater than that of pore pressure. 2) The critical pore pressure is between 1 and 1.5 MPa, the influence of slippage effect on permeability gradually decreases with the increase of temperature, and the gradient of influence reduction increases with the increase of burial depth. 3) The fracture opening coefficient increases with the increase of temperature and burial depth, but the higher the temperature, the smaller the change in the sensitivity of permeability to pore pressure under different burial depths. Conclusions These research results further enrich the theory of in-situ thermal injection mining of coalbed methane, and provide valuable data reference for enhanced permeability of coalbed methane.

Background Elevated white blood cell count, fibrinogen levels, and lower levels of albumin signify higher systemic inflammatory response, hypercoagulable state, and poorer nutritional status, respectively. However, a consistent conclusion could not be drawn on whether the association between inflammatory markers and cardiovascular disease was affected by the presence of chronic kidney disease (CKD). We aimed to explore the association between inflammation and adverse outcomes in patients with acute ischemic stroke (AIS), as well as whether this association differs due to the presence of CKD. Methods and Results This research was based on the Third China National Stroke Registry. The main adverse outcomes were poor functional outcome, stroke recurrence, and combined vascular event after 1 year. Inflammation was defined as the worst quartile of at least 2 of the aforementioned 3 markers. Finally, 8493 patients with AIS were enrolled in this study. The adjusted odds ratios/hazard ratios and 95% CIs of inflammation were 1.58 (1.34–1.86) for poor functional outcomes, 1.25 (1.06–1.47) for stroke recurrence, and 1.25 (1.06–1.46) for combined vascular event. The association between inflammation and adverse outcomes existed only in patients with AIS without CKD, although the interaction between CKD and inflammation was not statistically significant. (P for interaction >0.05). Conclusions Inflammation, which was defined as a combination of fibrinogen, white blood cell count, and albumin, was associated with all 1‐year adverse outcomes among patients with AIS. Routine assessment of these biomarkers could become a potential part of the clinical evaluation for patients with AIS, especially those without CKD, aiding clinicians in risk stratification and treatment decision‐making.

Conventional human-involved maintenance methods for asphalt pavement pose significant challenges when applied to high-traffic road sections, often leading to congestion and safety risks, as well as reduced maintenance efficiency. In recent years, explorations into unmanned construction technology for newly constructed expressways have yielded beneficial and encouraging results. However, its application in road maintenance in more complex environments still needs to be expanded. In this study, an intelligent unmanned maintenance technology for asphalt pavement was applied to the Lilong Highway in Zhejiang Province, China, and the compactability, thickness, surface smoothness, permeability coefficient, and constructure depth of maintenance road sections were measured. Then, based on fuzzy comprehensive mathematics and the analytic hierarchy process, a comprehensive evaluation was performed on the intelligent unmanned maintenance technology, considering the aspects of road quality, safety, application, and socio-economic benefits. The results show that the road quality of intelligent unmanned maintenance technology can meet the road specification requirements. In addition, the membership degree of unmanned maintenance technology in the excellent grade is the highest, reaching 0.805, and the quantified value for the overall evaluation of the application effectiveness of unmanned maintenance technology is 92.10. This means that the final comprehensive evaluation result of unmanned maintenance technology is rated as excellent. The research findings provide decision-makers with valuable insights into the unmanned automation maintenance challenges faced by asphalt pavement, enabling them to implement appropriate measures to elevate the maintenance standards of road transportation.

This research addresses the paramount issue of enhancing safety and health conditions in underground mines through the selection of optimal sensor technologies. A novel hybrid MEREC-CoCoSo system is proposed, integrating the strengths of the MEREC (Method for Eliciting Relative Weights) and Combined Compromise Solution (CoCoSo) methods. The study involves a three-stage framework: criteria and sensor discernment, criteria weight determination using MEREC, and sensor prioritization through the MEREC-CoCoSo framework. Fifteen criteria and ten sensors were identified, and a comprehensive analysis, including MEREC-based weight determination, led to the prioritization of “Ease of Installation” as the most critical criterion. Proximity sensors were identified as the optimal choice, followed by biometric sensors, gas sensors, and temperature and humidity sensors. To validate the effectiveness of the proposed MEREC-CoCoSo model, a rigorous comparison was conducted with established methods, including VIKOR, TOPSIS, TODIM, ELECTRE, COPRAS, EDAS, and TRUST. The comparison encompassed relevant metrics such as accuracy, sensitivity, and specificity, providing a comprehensive understanding of the proposed model’s performance in relation to other established methodologies. The outcomes of this comparative analysis consistently demonstrated the superiority of the MEREC-CoCoSo model in accurately selecting the best sensor for ensuring safety and health in underground mining. Notably, the proposed model exhibited higher accuracy rates, increased sensitivity, and improved specificity compared to alternative methods. These results affirm the robustness and reliability of the MEREC-CoCoSo model, establishing it as a state-of-the-art decision-making framework for sensor selection in underground mine safety. The inclusion of these actual results enhances the clarity and credibility of our research, providing valuable insights into the superior performance of the proposed model compared to existing methodologies. The main objective of this research is to develop a robust decision-making framework for optimal sensor selection in underground mines, with a focus on enhancing safety and health conditions. The study seeks to identify and prioritize critical criteria for sensor selection in the context of underground mine safety. The research strives to contribute to the mining industry by offering a structured and effective approach to sensor selection, prioritizing safety and health in underground mining operations.

Recycling agents (RAs) can mitigate the adverse effects of reclaimed asphalt pavement (RAP) on recycled asphalt, which can result in more RAP being added. To explore the effects of four RAs on recycled asphalt, this study used asphalt rheological performance experiments, including the bending beam rheometer (BBR) test, the dynamic shear rheological (DSR) test, and the indirect tensile asphalt cracking test (IDEAL-CT), to study the performance grade (PG), cracking resistance, and cracking susceptibility of recycled asphalt. In addition, an aging model for asphalt was used, and short-term and long-term aging sensitivities were evaluated according to this model. Results showed that US Soybean significantly enhanced the high-temperature and low-temperature performance grade (PGLT) and cracking resistance and reduced cracking sensitivity of the recycled asphalt. In addition, the short-term aging sensitivity was the lowest. It showed the best regeneration effect. However, the recycled asphalt with US Soybean showed the highest long-term aging sensitivity, suggesting that longer aging time results in poorer performance. Ingevity’s PG, cracking resistance, and cracking sensitivity are slightly lower than that of US Soybean, and Ingevity demonstrated the second lowest short-term aging sensitivity. However, its prolonged aging sensitivity was much lower than that of US Soybean. Asphalt and Wax Innovations and Georgia Pacific agents slightly improved recycled asphalt properties. The long-term aging sensitivity of recycled asphalt with four Ras was higher than that of recycled asphalt without Ras. These results indicated that the recycled asphalt’s performance with Ras worsened as aging time increased compared to the original recycled asphalt.

Aging can significantly affect the performance of asphalt mixtures, causing increase in stiffness, reduction in relaxation capability and increase in cracking susceptibility. It is also well known that fundamental viscoelastic properties are used for design and modelling of asphalt mixtures and pavement structures to addressing rutting, fatigue and thermal cracking concerns. The objective of this paper is to study how the viscoelastic properties of asphalt mixture change over time, and evaluate and identify the cracking and aging susceptibility of asphalt mixtures with different mix variables during material selection and mixture design. Ten mixtures are evaluated using different laboratory conditioning protocols to simulate a range of aging levels in the field. The complex modulus test is then conducted on the lab aged mixtures to measure the viscoelastic properties in order to construct the dynamic modulus and phase angle master curves. The mixture Glover-Rowe (G-Rm) parameter and the shape parameters of the dynamic modulus and phase angle master curves, including inflection point frequency (−β/γ), difference between the glassy modulus and the inflection point modulus (γ), peak value of phase angle (a) and the horizontal position (frequency) of the peak phase angle value (c), are determined and evaluated for the mixtures with different aging conditions and mix variables. The study indicates the ability of the G-Rm parameter and all the master curve shape parameters to capture the effect of different aging conditions on linear viscoelastic mixture properties, as well as the cracking and aging susceptibility of asphalt mixtures.

Background and purposeStudies showed that patients with hemorrhagic stroke are at a higher risk of developing deep vein thrombosis (DVT) than those with ischemic stroke. We aimed to develop a risk score (intracerebral hemorrhage-associated deep vein thrombosis score, ICH-DVT) for predicting in-hospital DVT after ICH.MethodsThe ICH-DVT was developed based on the Beijing Registration of Intracerebral Hemorrhage, in which eligible patients were randomly divided into derivation (60%) and internal validation cohorts (40%). External validation was performed using the iMCAS study (In-hospital Medical Complication after Acute Stroke). Independent predictors of in-hospital DVT after ICH were obtained using multivariable logistic regression, and β-coefficients were used to generate a scoring system of the ICH-DVT. The area under the receiver operating characteristic curve (AUROC) and the Hosmer–Lemeshow goodness-of-fit test were used to assess model discrimination and calibration, respectively.ResultsThe overall in-hospital DVT after ICH was 6.3%, 6.0%, and 5.7% in the derivation (n = 1,309), internal validation (n = 655), and external validation (n = 314) cohorts, respectively. A 31-point ICH-DVT was developed from the set of independent predictors including age, hematoma volume, subarachnoid extension, pneumonia, gastrointestinal bleeding, and length of hospitalization. The ICH-DVT showed good discrimination (AUROC) in the derivation (0.81; 95%CI = 0.79–0.83), internal validation (0.83, 95%CI = 0.80–0.86), and external validation (0.88; 95%CI = 0.84–0.92) cohorts. The ICH-DVT was well calibrated (Hosmer–Lemeshow test) in the derivation (P = 0.53), internal validation (P = 0.38), and external validation (P = 0.06) cohorts.ConclusionThe ICH-DVT is a valid grading scale for predicting in-hospital DVT after ICH. Further studies on the effect of the ICH-DVT on clinical outcomes after ICH are warranted.

Summary: Background: The disability weight (DW) quantifies the severity of health states from disease sequela and is a pivotal parameter for disease burden calculation. We conducted a national and subnational DW measurement in China. Methods: In 2020–2021, we conducted a web-based survey to assess DWs for 206 health states in 31 Chinese provinces targeting health workers via professional networks. We fielded questions of paired comparison (PC) and population health equivalence (PHE). The PC data were analysed by probit regression analysis, and the regression results were anchored by results from the PHE responses on the DW scale between 0 (no loss of health) and 1 (health loss equivalent to death). Findings: We used PC responses from 468,541 respondents to estimate DWs of health states. Eight of 11 domains of health had significantly negative coefficients in the regression of the difference between Chinese and Global Burden of Disease (GBD) DWs, suggesting lower DW values for health states with mention of these domains in their lay description. We noted considerable heterogeneity within domains, however. After applying these Chinese DWs to the 2019 GBD estimates for China, total years lived with disability (YLDs) increased by 14·9% to 177 million despite lower estimates for musculoskeletal disorders, cardiovascular diseases, mental disorders, diabetes and chronic kidney disease. The lower estimates of YLDs for these conditions were more than offset by higher estimates of common, low-severity conditions. Interpretation: The differences between the GBD and Chinese DWs suggest that there might be some contextual factors influencing the valuation of health states. While the reduced estimates for mental disorders, alcohol use disorder, and dementia could hint at a culturally different valuation of these conditions in China, the much greater shifts in YLDs from low-severity conditions more likely reflects methodological difficulty to distinguish between health states that vary a little in absolute DW value but a lot in relative terms. Funding: This work was supported by the National Natural Science Foundation of China [grant number 82173626], the National Key Research and Development Program of China [grant numbers 2018YFC1315302], Wuhan Medical Research Program of Joint Fund of Hubei Health Committee [grant number WJ2019H304], and Ningxia Natural Science Foundation Project [grant number 2020AAC03436].

Abstract Background Chronic alcohol consumption initially leads to asymptomatic left ventricular dysfunction, but can result in myocardial impairment and heart failure if ongoing. This study sought to characterize myocardial tissues and oxidative metabolism in asymptomatic subjects with chronic alcohol consumption by quantitative cardiovascular magnetic resonance (CMR) and 11C-acetate positron emission tomography (PET)/computed tomography (CT). Methods Thirty-four male subjects (48.8 ± 9.1 years) with alcohol consumption > 28 g/day for > 10 years and 35 age-matched healthy male subjects (49.5 ± 9.7 years) underwent CMR and 11C-acetate PET/CT. Native and post T1 values and extracellular volume (ECV) from CMR and Kmono and K1 from PET imaging were measured. Quantitative measurements by CMR and PET imaging were compared between subjects with moderate to heavy alcohol consumption and healthy controls, and their correlations were also analyzed. Results Compared to healthy controls, subjects with alcohol consumption showed significantly shorter native T1 (1133 ± 65 ms vs. 1186 ± 31 ms, p 0.05). In contrast, subjects with heavy alcohol consumption showed significantly lower Kmono values compared to those with moderate alcohol consumption (52.9 ± 12.1 min− 1 × 10− 3 vs. 63.7 ± 9.2 min− 1 × 10− 3, p = 0.012). Strong and moderate correlations were found between K1 and ECV in healthy controls (r = 0.689, p = 0.013) and subjects with moderate alcohol consumption (r = 0.518, p = 0.048), respectively. Conclusion Asymptomatic men with heavy alcohol consumption have detectable structural and metabolic changes in myocardium on CMR and 11C-acetate PET/CT. Compared with quantitative CMR, 11C-acetate PET/CT imaging may be more sensitive for detecting differences in myocardial damage among subjects with moderate to heavy alcohol consumption.

It has been widely reported that biochar can be used as a cost-effective amendment to immobilize of heavy metal contaminants in soil. While less research has been conducted on effect of biochar long-term field aging on its properties and the adsorption capability. In this study, the characteristics of aged biochar were investigated by comprehensive characterization to elucidate its mechanism transformation for heavy metal immobilization. Our results showed that, compared to fresh biochar, the relative content of C of aged biochar was reduced by 34.12%, while O was increased by 8.79%. Additionally, the specific surface area, pore volume, pore size and oxygen-containing functional groups of aged biochar were significantly increased compared to the fresh biochar. Batch adsorption experiment indicated that the maximum adsorption for Cd2+ (Qm = 32.157 mg/g) and Pb2+ (Qm = 39.216 mg/g) on aged biochar surface was much larger than that of Cd2+ (Qm = 7.573 mg/g) and Pb2+ (Qm = 8.134 mg/g) on fresh biochar. The underlying adsorption mechanisms for Cd2+ and Pb2+ on fresh biochar were dominated by coprecipitation, cation exchange and cation-π interaction, whereas surface complexation and cation exchange appeared to be more vital for aged biochar, as more active adsorption sites and Oxygen-containing functional groups were formed on its surface during aging, which was well explained by BET, XPS, FTIR and Elemental Analysis. Our study found that the physicochemical properties of biochar changed significantly during field aging. Although these changes increased the adsorption of heavy metals by biochar, the reduced stability of biochar to passivated heavy metal ions.

Background Anemia or low hemoglobin can increase the risk of stroke. However, the association between hemoglobin and outcomes after stroke is uncertain. In this study, we aimed to investigate the association between hemoglobin and clinical outcomes, including mortality, poor functional outcome, stroke recurrence, and composite vascular events at 1 year. Methods and Results We included the patients diagnosed with acute ischemic stroke or transient ischemic attack from the Third China National Stroke Registry. We used the Cox model for mortality, stroke recurrence, and composite vascular events and the logistic model for the poor functional outcome to examine the relationship between hemoglobin and clinical outcomes. In addition, we used the restricted cubic spline to evaluate the nonlinear relationship. This study included 14 159 patients with acute ischemic stroke or transient ischemic attack. After adjusted for potential cofounders, both anemia and high hemoglobin were associated with the higher risk of mortality (hazard ratio [HR], 1.73; 95% CI, 1.39–2.15; HR, 2.71; 95% CI, 1.95–3.76) and poor functional outcome (odds ratio [OR], 1.36; 95% CI, 1.18–1.57; OR, 1.42; 95% CI, 1.07–1.87). High hemoglobin, but not anemia, increased the risk of stroke recurrence (HR, 1.37; 95% CI, 1.05–1.79) and composite vascular events (HR, 1.41; 95% CI, 1.08–1.83). There was a U‐shaped relationship between hemoglobin and mortality and poor functional outcome. Conclusions Abnormal hemoglobin was associated with a higher risk of all‐cause mortality, poor functional outcome, stroke recurrence, and composite vascular events. More well‐designed clinical studies are needed to confirm the relationship between hemoglobin and clinical outcomes after stroke.

Background and Aims: YKL-40, an inflammatory biomarker, has been reported to be involved in the process and progression of atherosclerosis. Several studies have investigated the association between YKL-40 and plaque and suggested YKL-40 might be a potential biomarker for plaque instability. This study aimed to investigate the association between YKL-40 and carotid plaque instability.Methods: Based on a community-based study in Beijing from February 2014 to May 2016, 1,132 participants with carotid plaques were enrolled in this study. Data on demographics and medical history were collected through face-to-face interviews, and fasting blood samples were collected and stored. We used ultrasound to evaluate the presence of carotid plaque and its instability. The level of YKL-40 was measured by enzyme-linked immunosorbent assay (ELISA). Multivariate logistic regression analysis was performed to investigate the association between YKL-40 level and carotid atherosclerotic plaque instability.Results: The mean age of the 1,132 participants was 58.0 (52.0–64.0) years, and 560 (49.5%) were male. Unstable plaques were detected in 855 (75.53%) participants. YKL-40 level was classified into four groups according to its quartile: quartile 1:

Background The 1-month case fatality of ischaemic stroke is an essential epidemiological metric. Whereas the case fatality after ischaemic stroke and the temporal trend is uncertain. We aimed to estimate the 1-month case fatality of ischaemic stroke and its temporal trend, as well as its regional variation.Methods We searched PubMed and Embase to identify the studies for 1-month case fatality of ischaemic stroke . The population-based studies were included. Two investigators extracted the data and assessed the quality independently. One-month case fatality of ischaemic stroke was estimated using a random effects model. The temporal trend was evaluated using a mixed-effect meta-regression model.Results A total of 59 articles with 77 time periods were included. The worldwide 1-month case fatality of ischaemic stroke was 13.5% (95% CI 12.3% to 14.7%). The case fatality was 10.8% (95% CI 8.3% to 13.5%) in Asia, 14.2% (95% CI 12.6% to 15.9%) in Europe, 14.0% (95% CI 11.2% to 17.1%) in South America and Caribbean, 14.0% (95% CI 9.5% to 19.1%) in North America and 12.5% (95% CI 11.1% to 13.9%) in Australia and New Zealand. Overall, there was a non-significant decrease of 0.1% per year in case fatality. It decreased significantly in Europe (−0.2% annually, 95% CI −0.4% to −0.01%) and North America (−0.2% annually, 95% CI −0.4% to −0.04%), increased significantly in Australia and New Zealand (0.2% annually, 95% CI 0.1% to 0.4%), while no evidence of change in other regions.Conclusion The 1-month case fatality of ischaemic stroke and its temporal trend were divergent across regions. Further studies are needed to address the reason of the regional difference, which will be helpful to guide the effort of reducing stroke burden.

Abstract Background Accumulating evidence has shown that cigarette smoking is an important risk factor for ischemic stroke. However, it is not clear about the potential mechanisms through which cigarette smoking affects stroke risk. In the study, we aimed to investigate the relationship between cigarette smoking and the occurrence of extracranial (ECAS) and intracranial atherosclerotic stenosis (ICAS). Methods We analyzed patients enrolled in the Chinese intracranial atherosclerosis (CICAS), which was a prospective, multicenter, hospital-based cohort study. Smoking status was classified into never, former and current smoking. For those patients with current smoking, data on time duration (year) and extent (the number of cigarette smoked per day) was recorded and pack year of smoking was calculated. ICAS was evaluated with 3-dimentional time-of-flight MRA and ECAS was evaluated with cervical ultrasonography or contrast-enhanced MRA. Multivariable Logistic regression was performed to identify the association between smoking status and the occurrence of ECAS and ICAS. Results A total of 2656 patients (92.7%) of acute ischemic stroke and 208 (7.3%) of transient ischemic attack were analyzed. The mean age was 61.9 ± 11.2 and 67.8% were male. There were 141 (4.9%) patients had only ECAS, 1074 (37.5%) had only ICAS, and 261 (9.1%) had both ECAS and ICAS. Current smoking was significantly associated with the occurrence of ECAS (adjusted OR = 1.47, 95% CI = 1.09–1.99, P

The balance between crop yield, quality and soil nutrient status can be manipulated by exploiting nutrient interactions. Field experiments were conducted in citrus orchards in Danjiangkou, Hubei Province to assess the effects of N (0, 0.3, 0.6 and 0.9 kg plant−1), P (0, 0.1, 0.2, 0.3 kg plant−1), K (0, 0.15, 0.30, 0.45 kg plant−1) and their interactions on residual nutrient content in soils, and the yield and quality of satsumas. The results showed that the effects of N and K fertilizers on the yield and quality of satsumas were greater than those of P fertilizers. Appropriate application rates of N (0.6 kg plant−1), P (0.3 kg plant−1) and K (0.15 kg plant−1) significantly improved yield and quality. Lack or excess or inappropriate ratios of N, P and K fertilizer can affect the absorption and utilization of nutrients and reduce yield and quality. The best fertilizer combination, determined by comprehensively considering yield, quality and environment, was N0.3P0.2K0.3, which delivered moderate yield, high fruit quality and low potential risk of pollution. The amount of fertilizer in this case was 0.3 kg N, 0.2 kg P, 0.3 kg K per plant, which is lower than the current recommended application rates (0.5–0.8 kg N, 0.2–0.5 kg P, 0.25–0.64 kg K, respectively). The economic benefit did not decrease because of a decline of yield, but increased slightly because of the improved fruit quality and the reduction in fertilizer input, compared with the treatment with the highest yield. Therefore, we suggest that it is necessary to consider the quality of agricultural products and environmental protection when applying fertilizer and to reduce N and P fertilizer input and appropriately increase the proportion of K. Keywords: Interaction of NPK fertilizer, Citrus, Balanced fertilization, Optimum fertilization rate, Yield, Quality

Background and Purpose: A large body of literature reported the association of particulate matter (PM) with stroke in high-income countries. Few studies have examined the association between PM and stroke in middle- and low-income countries and considered the types of stroke. In this study, we examined the short-term effects of particulate matter

[This corrects the article DOI: 10.1371/journal.pone.0168384.].

Mulching management has been used in many places all over the world to improve agricultural sustainability. However, the cycling of carbon in the soil under applications of mulch on sloping arable land is not yet fully understood. A four-year field experiment was carried out in Xiaofuling watershed of Danjiangkou reservoir in China. The object was to evaluate the effects of the application of straw mulch (ST) and grass mulch (GT) on dynamic changes in soil organic carbon and its fractions. Results showed that mulch applied on the soil surface increased the contents of SOC and its active fractions in the soil. Compared to the control without cover (CK), ST and GT treatments increased the contents of SOC, LOC, DOC, POC and EOC by 14.73%, 16.5%, 22.5%, 41.5% and 21%, respectively, in the 0-40 cm soil layer, and by 17%, 14%, 19%, and 30%, respectively, in the 0-100 cm soil layer. The contents of organic carbon and its active fractions decreased with increasing soil depth in all of the treatments. SOC was accumulated in the period of December to the following March. The contents of soil DOC and LOC were high in January to March, while the contents of soil POC and EOC were high in June to September. The relative contents of soil organic carbon fractions were POC > EOC > LOC > DOC over the four years. Straw mulching had no significant effect on the changes in soil organic carbon active fractions during the different periods. Based on this long-term field experiment in Danjiangkou reservoir, we found that straw mulching had a significant effect on soil, increasing SOC content and stock in slopping arable land, and that live grass mulching was more effective than rice straw mulching. We discuss possible optimal periods for the implementation of mulching practices on sloping land.

The quality of after-hour emergency care of patients with acute ischemic stroke is debatable. We therefore, sought to analyze the performance measures, quality of care and clinical outcomes in these patients admitted during off-hours.Our study included 4493 patients from a selected cohort of patients admitted to the hospitals with ischemic stroke in the China National Stroke Registry (CNSR) from September 2007 to August 2008. On-hour presentation was defined as arrival at the emergency department from the scene between 8AM and 5PM from Monday through Friday. Off-hours included the remainder of the on-hours and statutory holidays. The association between off-hour presentation and outcome was analyzed using multivariate logistic-regression models.Off-hour presentation was identified in 2672 (59.5%) patients with ischemic stroke. Comparison of patients admitted during off-hours with those admitted during on-hours revealed an unadjusted odds ratio of in-hospital mortality of 1.38 (95% confidence interval, 1.04-1.85), which declined to 1.34 (95% confidence interval, 0.93-1.93) after adjusting for patient characteristics (especially, pre-hospital delay). No difference in 30-day mortality, total death or dependence at three, six and 12 months between two groups was observed. No association between off-hour admission and quality of care was found.In the CNSR database, compared with on-hour patients, off-hour patients with acute ischemic stroke admitted to the emergency departments from scene manifested a higher incidence of in-hospital mortality. However, the difference in incidence and quality of care between the groups disappeared after adjusting for pre-hospital delay and other variables.