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Introduction: Stroke is a leading cause of death and disability worldwide. Antiplatelet therapies are recommended to reduce the risk of recurrent stroke in patients with ischemic stroke/transient ischemic attack (IS/TIA). This study evaluated outpatient antiplatelet treatment patterns and outcomes for secondary stroke prevention (SSP) among UK adults without atrial fibrillation who were hospitalized for IS/TIA. Methods: This retrospective observational study utilized data from the UK Clinical Practice Research Datalink linked with Hospital Episode Statistics data (01/01/2011–30/06/2019). Treatment patterns included type and duration of treatments. Treatment outcomes included IS, myocardial infarction, major bleeding, and cardiovascular-related and all-cause mortality. Descriptive statistics were reported. Results: Of 9270 patients, 13.9% (1292) might not receive antithrombotic therapy within 90 days of hospital discharge. Of 7978 patients who received antiplatelet therapies, most used clopidogrel (74.8%) or aspirin (16.7%) single antiplatelet therapy and clopidogrel + aspirin dual antiplatelet therapy (DAPT, 5.9%). At 1-year post-hospitalization, 36.9, 43.3, and 35.1% of those receiving these treatments discontinued them, respectively, and of the patients initiating DAPT, 62.3% switched to single antiplatelet therapy. At 1-year post-discharge, the incidence rate (per 100 person-years) of IS, myocardial infarction, major bleeding, cardiovascular-related mortality, and all-cause mortality among the treated were 6.5, 0.7, 4.1, 5.0, and 7.3, respectively, and among the untreated were 14.9, 0.7, 8.6, 28.1, and 39.8, respectively. Conclusions: In the United Kingdom, 13.9% of patients hospitalized for stroke might not have any antiplatelet treatment to prevent secondary stroke; among the treated, clopidogrel, aspirin, and DAPT were commonly used. These study findings suggest that improved anti-thrombotic therapies for long-term SSP treatment are needed, which may lead to higher treatment and persistence rates and, therefore, improved outcomes in this population. [ABSTRACT FROM AUTHOR]

Vacuum counter-pressure casting (VCPC) process is an effective forming process of producing components with complex thin-walled characteristics. In this study, a surrogate-based optimization method with five process parameters is used to reduce the shrinkage porosity defect during the VCPC process of a complicated thin-walled aluminum alloy casing. The prediction of the shrinkage porosity defect is implemented by using the numerical simulation of the VCPC process. In general, performing the optimization directly based on the casting simulation may not be practical due to the computational and time constraints. To mitigate this problem, the response surface model (RSM) constructed via computer experiments is employed to accurately approximate the functional relationship between the process parameters and the response variable which is defined as the area of defects in the defect image generated from the casting simulation. To measure the area of defects in the image, a histogram-based threshold segmentation approach is proposed to recognize and quantify the defects from the image. The optimization problem is subsequently formulated using a desirability function-based optimization method, and the objective function is estimated using the built RSMs. The final results indicate that a set of optimal process parameters with minimum defects can be obtained. [ABSTRACT FROM AUTHOR]

We report a facile and effective aerosol-spray strategy toward high-performance anodes for lithium-ion batteries by incorporating mesoporous SnO2 spheres of high-capacity materials with surface-modified carbon nanotubes (MCNTs). SnO2 nanocrystals are self-assembled into mesoporous spheres, and MCNTs with abundant carboxylic groups serve as a conductive scaffold. Driven by the strong interaction between the surface of metal oxide and the carboxylic groups on CNTs, a robust nanocomposite architecture is in situ formed. Such nanocomposite architecture possesses several advantages as an anode for lithium-ion batteries. First, mesoporous SnO2 spheres inherit the advantageous features of conventional nanoparticles, such as the capability to accommodate volume expansion and reduce Li+ diffusion distance. Second, the robust interface between nanocrystals in the SnO2 spheres provides the high structural stability that would prolong the life span of the electrode. Third, MCNTs that strongly bind to SnO2 spheres serve as a three-dimensional network, offering both improved electronic transport and mechanical strength of the electrode. Therefore, as-prepared nanocomposite delivers high capacity of 963 mAh g−1 at 0.1 C and 701 mAh g−1 at 5 C, respectively. Significantly improved cycling performance is achieved over the bare SnO2 spheres counterpart. [ABSTRACT FROM AUTHOR]

Leaves are vital plant organs, and a high level of variation in leaf shape, including the leaf lobes, is present in Brassica rapa. Based on a previously-constructed linkage map, QTL analysis of the leaf lobes was performed using the scores from an F population during the spring of 2010, and scores from an F family in the autumn of 2010, respectively. A total of nine QTLs were found to affect leaf lobes. Among these, a major QTL, lob 10.1, was mapped to the bottom of linkage group A10. To develop near iso-genic lines (NILs) for the identified major QTL, an F plant without leaf lobes that was homozygous in the targeted region for marker alleles from the male parent (08A061), was backcrossed to 09A001, the recurrent parent with leaf lobes. Two InDel marker loci, BrID10909 and BrID10233, which are closely linked to the major QTL peak position, and 166 SSR and InDel markers from non-targeted chromosomal regions, were used for foreground and background selection, respectively. Three sets of NILs were developed through four cycles of backcrossing followed by two cycles of self-pollination. Compared to 09A001, the recurrent parent, all the NILs showed the absence of leaf lobes and had no significant differences in other agriculturally important traits. NILs are the ideal genetic resource for QTL validation and fine-scale linkage mapping, and, ultimately, gene discovery. [ABSTRACT FROM AUTHOR]

China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P < 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures. Nitrogen from ammonium (NH4+) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3−), in agreement with decreased ratios of NH3 to NOx emissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment. [ABSTRACT FROM AUTHOR]

To evaluate the impact of N placement depth and no-till (NT) practice on the emissions of NO, N2O, CH4 and CO2 from soils, we conducted two N placement experiments in a long-term tillage experiment site in northeastern Colorado in 2004. Trace gas flux measurements were made 2–3 times per week, in zero-N fertilizer plots that were cropped continuously to corn ( Zea mays L.) under conventional-till (CT) and NT. Three N placement depths, replicated four times (5, 10 and 15 cm in Exp. 1 and 0, 5 and 10 cm in Exp. 2, respectively) were used. Liquid urea–ammonium nitrate (UAN, 224 kg N ha−1) was injected to the desired depth in the CT- or NT-soils in each experiment. Mean flux rates of NO, N2O, CH4 and CO2 ranged from 3.9 to 5.2 μg N m−2 h−1, 60.5 to 92.4 μg N m−2 h−1, −0.8 to 0.5 μg C m−2 h−1, and 42.1 to 81.7 mg C m−2 h−1 in both experiments, respectively. Deep N placement (10 and 15 cm) resulted in lower NO and N2O emissions compared with shallow N placement (0 and 5 cm) while CH4 and CO2 emissions were not affected by N placement in either experiment. Compared with N placement at 5 cm, for instance, averaged N2O emissions from N placement at 10 cm were reduced by more than 50% in both experiments. Generally, NT decreased NO emission and CH4 oxidation but increased N2O emissions compared with CT irrespective of N placement depths. Total net global warming potential (GWP) for N2O, CH4 and CO2 was reduced by deep N placement only in Exp. 1 but was increased by NT in both experiments. The study results suggest that deep N placement (e.g., 10 cm) will be an effective option for reducing N oxide emissions and GWP from both fertilized CT- and NT-soils. [ABSTRACT FROM AUTHOR]

For numerical investigation of the quasi-continuous laser beam welding (Q-CLBW) process, the existing research usually considered a constant welding heat input, which to some degree loses accuracy in representing the welding dynamics. This paper developed a validated CFD model for the simulation of Q-CLBW of Ti6Al4V alloy based on a near-reality heat source model. The coupled transient temperature, velocity, and phase fields were solved under a high-frequency pulsed laser power (HF-PLP) at 5000 Hz as well as a constant laser power (CLP) which has been conventionally employed. Comparative analysis was carried out with respect to keyhole stability, melt flow pattern, and weld pool dimensions resulting from different heat sources and different heat input values with laser peak power of 2800 ~ 3800 W and welding velocity of 0.02 ~ 0.04 m/s. Results indicate that the time-dependent laser input yields less stabilized dynamics featured with middle-depth keyhole collapse, chaotic melt flow, and periodic vapor eruption, and such characteristics are difficult to be observed with CLP. The maximum temperature, pressure, and velocity magnitude of molten metal present remarkable oscillations in relation to welding time. With decreasing heat input in HF-PLP welding cases, the keyhole geometry tends to collapse in the tip segment while the melt flow becomes regular. Furthermore, the employment of the HF-PLP condition also enhances the accuracy in predicting the cross-sectional seam profile in terms of width and depth. Pulsed laser input should be taken into full consideration in the numerical simulation of the Q-CLBW process. [ABSTRACT FROM AUTHOR]

By researching the distance between blasthole and interface of soft-hard rock strata, as well as the time of delay detonation, blasting effect of the rock mass will be more controllable. Firstly, validity of numerical method was authenticated from three angles: blasting coupled stress field, ratio of crushing zone radius to blasthole radius, and crack network state. Under the condition of soft-hard rock strata, numerical model of double-hole blasting was established by using PFC2D. Then delay blasting experiments were carried out under different relative positions of blasthole and interface. Ultimately, results were analyzed from three perspectives: crack network, crack quantity and rock fragment. Results show that: (1) When detonated in hard rock, if between interface and blasthole distance is greater than twice crushing zone radius, the closer blasthole is to the interface, the more obvious the "hook" phenomenon between the two blastholes is. With increasing delayed initiation time, "hook" phenomenon will weaken or even disappear. (2) Based on the crack information initiated in hard rock, the law of crack number varying with thickness of hard rock and delay time is obtained. (3) For initiation in hard rock, crack extension range is large, but less fragments are formed. The law is opposite to that initiation in structural plane and soft rock. Fragmentation area increases exponentially with increasing soft rock thickness, and exponential function is obtained. [ABSTRACT FROM AUTHOR]

Based on the digital elevation data, snow depth and snow cover remote sensing data, this paper divides six snow evolution areas and geographical partitions, extracts the geographical partitions of each evolution area and obtains the geographical characteristics of the evolution area for analysis. The results show that: (1) From 2003 to 2017, the average snow area decreased at a rate of − 0.004, and the average snow depth increased at a rate of 0.03. (2) The snow in the middle altitude hill with shady gentle slope area is the most obvious in the seasonal evolution, and the percentage of this region in the seasonal snow evolution area is 5.46%, the snow depth in the middle altitude hill with sunny and gentle slopes area increased and decreased significantly in the past 15 years, and the percentage of this region in the SD significant changes evolution area was 6.32%. The snow in the low relief middle altitude mountain with shady and moderate slope area not only shows obvious seasonal evolution, but also increases and decreases significantly in snow depth. And the percentage of this region in the seasonal snow significant evolution area is 5.82%. (3) The geographical partitions with the largest area in all evolution areas is the middle altitude hill with sunny and gentle slopes area (4.75%). (4) The geographical partition with the largest variation of snow depth in Tianshan region is the low relief middle altitude mountain with shady and moderate slope area (12.02 cm). (5) The snow accumulation and melting are obvious in the range of 1000–3500 m above altitude, different geomorphology types lead to obvious differences in snow characteristics. The snow melting is most obvious in the gentle slope area of the low topographic relief geomorphology types, and the snow accumulation is most obvious in the steep slope area of the middle relief geomorphology types. [ABSTRACT FROM AUTHOR]

The existence of various types of damage, small cracks, some large voids and the size of the sample in the rock will make the experimental results show great discreteness. In this paper, based on the results of laboratory experiments, a numerical model of large flawed rock samples is established by using particle flow software PFC2D, and the mechanical response of rocks with different length-diameter ratios and different flaw positions in uniaxial compression experiments is discussed. The results show that the specimen size has a significant effect on the crack characteristics, mechanical characteristics and energy characteristics of rock mass. From the perspective of energy and crack characteristics, the total number of cracks after the failure of the defective rock sample is slightly lower than that of the intact rock sample, resulting in a slightly lower peak strain energy during the rock failure process. From the mechanical properties of rock samples, the Poisson's ratio of intact rock samples is slightly smaller than that of defective rock samples. The strength of the defective sample is weakened relative to the complete rock sample, and the relationship formula between the weakening range and the aspect ratio is obtained through analysis. Moreover, different defect locations lead to different crack processes and crack modes, resulting in different uniaxial compressive strength. [ABSTRACT FROM AUTHOR]

Cyclic voltammetry (CV), 1H nuclear magnetic resonance (1H NMR), density functional theory (DFT), quantum theory of atoms in molecules (QTAIM) and reduced density gradient (RDG) were used to study the interactions of dopamine hydrochloride (DH) with nicotinic acid (NAC) in aqueous solution. The results revealed that there existed three weak interactions in the DH–NAC system, C–H···π, π···π stacking and hydrogen bonds. These interactions showed different effects on the DH electrooxidation and its chemical environment. Moreover, the CV and 1H NMR results indicated that C–H···π interaction between the H atoms on the benzene ring of DH and the pyridine ring of NAC, and π···π stacking between the benzene ring of DH and the pyridine ring of NAC are the main interactions in the system. [ABSTRACT FROM AUTHOR]

This study aims to know the seeking help behavior of individuals with SZ (Schizophrenia) in Hunan province of China. Individuals (age > 15) with schizophrenia were recruited in the study after a two-stage diagnosis procedure (including questionnaire screening and face-to-face SCID interview by psychiatrists) in Hunan province. A self-designed questionnaire was used to investigate their help-seeking behavior. (1) Of the 367 participants, 68.9% (253/367) sought help; of those, 64.6% (n = 163) pursued professional psychiatric services and 30.8% (n = 78) pursued non-medical options (i.e., relatives, praying to Buddha) as the most common first choices. (2) Family history of mental disorders is significantly related to whether or not the individual with SZ seeks help, and the first choice of help is significantly related to education level. (P < 0.05). (3) Frequent reasons behind not seeking help include fear of stigmatization (72.9%), poor mental health literacy (64.5%), concerns over cost (50.6%), and limited access to medical services (47.0%). About one-third of the individuals do not seek help. Individuals with SZ tend to choose psychiatric hospitals and relatives as their first choice. Among the factors we investigated, family history of mental disorders is the most influential factor associated with help-seeking behavior. Individuals with more education tend to seek professional help first. The primary reasons for not seeking help include fear of stigmatization, lack of awareness about mental illness, concerns over cost, etc. [ABSTRACT FROM AUTHOR]

Overuse of urea, low nitrogen (N) utilization, and large N losses are common in maize production in North China Plain (NCP). To solve these problems, we conducted two field experiments at Shangzhuang and Quzhou in NCP to test the ability of a newly developed urease inhibitor product Limus® to decrease NH3 volatilization from urea applied to maize. Grain yield, apparent N recovery efficiency (REN) and N balance when using urea applied with or without Limus were also measured over two maize growing seasons. Cumulative NH3 loss in the two weeks following urea application without Limus ranged from 9-108 kg N ha−1, while Limus addition significantly decreased NH3 loss by a mean of 84%. Urea with Limus did not significantly increase maize yields (P < 0.05) compared with urea alone. However, a significant 11-17% improvement in REN with Limus was observed at QZ. The use of urea-N plus Limus would permit a reduction in N applications of 55-60% compared to farmers' practice and/or further 20% N saving compared with optimized urea-N rate (150 kg N ha−1, based on N requirement by target yield of 7.5 t ha−1), and would achieve the same maize yields but with significantly decreased NH3 loss and increased N utilization. [ABSTRACT FROM AUTHOR]

A correction to the article related to the modelling the dynamics of organic carbon in fertilization using the Rothamsted Carbon Model-initialization in the North China Plain.