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Endophytic fungi is an important source for the discovery of bioactive natural compounds. A chemical investigation of the ethyl acetate extract of the endophytic fungus Schizophyllum sp. HM230 derived from stems of the herb Vincetoxicum mongolicum Maxim led to isolation of five alkaloids, including two new compounds, schizophyllins M (1) and N (2), along with three known ones (3–5). The planar structures of two new compounds were elucidated by extensive spectroscopic methods including MS, 1D and 2D NMR. Their absolute configurations were determined by Mosher's method and comparison of the ECD data. All the isolates were evaluated for their cytotoxicity and antioxidant activities. Compounds 1–4 showed middle cytotoxicity against MCF-7 cells with IC50 values range of 68.1 ∼ 87.32 μM. Compounds 1–5 displayed obvious antioxidant activity with the IC50 values range of 0.86 ∼ 5.78 mg/mL. [ABSTRACT FROM AUTHOR]

In this article, the distributed adaptive finite-time containment control problem is investigated for nonlinear multi-agent systems with unknown input saturations. Since the leaders are only available to partial subsystems, a distributed estimator is designed to estimate the local reference signals. The saturated function is converted to the combination of a linear part and a nonlinear part, thus overcomes the difficulties caused by unknown saturated bounds. By utilising the command filtered and backstepping control techniques, a two-step method is adopted to construct the controller, under which the effect of unknown input saturations can be compensated well. It is proved that the closed-loop system is practical finite-time stable, and the output of each follower can converge to the dynamic convex hull spanned by the leaders in finite time. Finally, a group of four one-link manipulator systems is used to support the feasibility of the developed control scheme. [ABSTRACT FROM AUTHOR]

Two neolignan glycosides including a new one (1), along with seven iridoid glycosides (3 − 9) and nine flavonoid glycosides (10 − 18), were isolated from the leaves of Vaccinium bracteatum. Their structures were established mainly on the basis of 1D/2D NMR and ESIMS analyses, as well as comparison to known compounds in the literature. The structure of 1 with absolute stereochemistry was also confirmed by chemical degradation and ECD calculation. Selective compounds showed antiradical activity against ABTS and/or DPPH. Moreover, several isolates also suppressed the production of ROS in RAW264.7 cells and exerted neuroprotective effect toward PC12 cells. [ABSTRACT FROM AUTHOR]

Reflux hypersensitivity (RH) is a subtype of gastroesophageal reflux disease. The Rome IV criteria separated RH from the original nonerosive reflux disease subgroup and classified it as a new functional oesophageal disease. Recently, the pathogenesis of RH has become the focus of research. According to the latest research reports, upregulation of acid-sensitive receptors, distribution of calcitonin gene-related peptide-positive nerve fibres, and psychiatric comorbidity have key roles in the pathogenesis of RH. This work reviews the latest findings regarding RH mechanisms. [ABSTRACT FROM AUTHOR]

Social gamification, which allows technology users to interact with each other in gamified tasks, has drawn increasing interest due to its effectiveness in facilitating users' game engagement and task efforts. In social gamification, users can compete or cooperate with other users or teams to complete game tasks and achieve game goals. However, it remains unclear how various social interaction mechanisms (SIMs), such as cooperation, interpersonal competition, and intergroup competition, influence gamification outcomes when they are separately or jointly implemented. In addition, the effects of SIMs on experiential and instrumental gamification outcomes have not been well differentiated. In this study, we systematically investigate the influences of these fundamental SIMs, as well as the possible interaction effects among them, on fitness app users' game engagement and fitness behavior. Using a fitness app custom-developed for the Chinese market, Fitness Castle, we conducted a longitudinal field experiment to test our proposed model and hypotheses. The results indicate that when separately implemented, cooperation and interpersonal competition can lead to differential instrumental gamification outcomes in the fitness context. We also systematically compare the differential gamification outcomes when cooperation, interpersonal competition, and intergroup competition are combined in various coopetition settings. Our study offers a theory-based framework and design principles for social gamification. Our findings help practitioners better design SIMs in their gamified technologies with the purpose of achieving optimal experiential and instrumental gamification outcomes simultaneously. [ABSTRACT FROM AUTHOR]

The undercooled solidification of the Inconel 718 superalloy under high magnetic field was performed for the first time at high undercoolings (∼ 200 °C). The results show that the high magnetic field can significantly refine the grains of the undercooled alloys, with the average grain size decreasing from 241 ± 92 μm at 0 T to about a third under high magnetic fields (3 T ∼ 9 T). Detailed EBSD analysis provides clear evidence that Icosahedral Short-Range Order (ISRO) enhanced nucleation occurs. The present work opens up a new way for grain refinement of alloys. This work shows for the first time that an applied high static magnetic field can induce significant grain refinement in the undercooled IN718 superalloy, and provides clear evidence that ISRO-enhanced nucleation occurs. [ABSTRACT FROM AUTHOR]

Core patents are the most important in a specific technological field. Forecasting core patents is crucial to understanding the development of technology trends. Traditional approaches are based on structured/unstructured features or patent relationships. However, most previous methods focused on specific aspects of patents. We propose a novel framework based on the potential relationships to forecast core patents. An event study approach is applied to analyze the short-term impact of core patents' granting events on the stock market. We apply three methods to build framework: a baseline model using traditional features and two graph embeddings. Finally, a classification model is used to predict and compare the effectiveness of different inputs: the traditional patent feature index, and the feature vectors output by the Node2vec and GraphSAGE models. We verify the method with data from the communications and biomedical industries and investigate its application to the stock market. Results demonstrate that the graph-embedding features based on the network are superior to traditional patent features. The graph neural network effectively fuses the two sets of information, and forecasting is improved in all models. And we find that the cumulative abnormal returns from core patents' granting events outweigh those for non-core (ordinary) patents. [ABSTRACT FROM AUTHOR]

Augmented Reality (AR) has the potential to help drivers become aware of invisible hazards through an Augmented Reality Head-Up Display (AR-HUD). However, this issue is still underexplored. To address it, a novel warning system for invisible dangers in AR-HUD user interfaces has been designed as a carrier for agents' cognitive information to enhance driver perception. This design was created by using a team cooperation perception model that combined the perception cycle of a human driver with a computational agent. Furthermore, user experiments were conducted to investigate the impact of this design on safe driving in two typical scenarios. The experimental results showed that this design can significantly improve drivers' situation awareness and reaction time in both human-driving and auto-pilot modes, and enhance human drivers' trust in the auto-pilot system. The model and design can be generalized to more AR-HUD scenarios requiring human-machine perception and cognitive cooperation. [ABSTRACT FROM AUTHOR]

In this paper we propose a new nonparametric regression technique under multiplicative distortion measurement errors settings. The unobservable variables are both distorted in a multiplicative fashion by an observed confounding variable. A bias reduction is proposed by choosing a function that is the projection of the unknown regression function onto the parametric family in a certain metric. We find that this new technique leads to substantial improvement in the performance of regression estimators in comparison with the direct one-step estimation, irrespective of the choice of a parametric model. We obtain asymptotic normality results for the estimated nonparametric kernel smoothers, and further discuss their estimation efficiency. We conduct Monte Carlo simulation experiments to examine the performance of the proposed estimators. [ABSTRACT FROM AUTHOR]

Despite rapid economic growth in China since 1978, rural-urban inequality has widened. High levels of socioeconomic inequality can have profound implications for child development and lifelong educational equity. Using a dataset containing early childhood development (ECD) outcomes of 0- to 3-year-olds (N = 9,053) from study sites in Eastern, Central, and Western China, the study finds that the risks of cognitive, language, and motor delay are, respectively, 43.2, 18.3, and 20.7 percentage points higher in rural study sites than in urban Shanghai (ps <.01). Impact evaluation of cluster-randomized experiments shows that parental training (focusing on child psychosocial stimulation and caregiver-child interaction) can improve parenting beliefs and practices (or investments) and ECD outcomes of disadvantaged rural children (p<.01). Such programs can play an important role in advancing progress toward more social equality and economic equity, the stated goals of China's "Common Prosperity" policy. [ABSTRACT FROM AUTHOR]

AbstractWe consider the estimation of Pearson correlation coefficient when two continuous variables can not be directly observed but measured with multiplicative distortion measurement errors. Different from the identifiability conditions for the distortion functions in literature, we propose a new estimation method of Pearson correlation coefficient by transforming the linear model between two variables into varying coefficient models, a moment-based estimator of the Pearson correlation coefficient is proposed. This method can deal with the non-independence condition between the confounding variable and the unobserved variables. We study the asymptotic results of these proposed estimators, and we make some comparisons among the proposed estimators through the simulation. These methods are applied to analyze a real dataset for an illustration. [ABSTRACT FROM AUTHOR]

The development of rapid methods for in situ chromium determination in natural water is important. A new nanocomposite was fabricated by impregnating gold nanoparticles onto archetypical UiO-66 metal organic frameworks and modifying glassy carbon electrodes (Au/UiO-66/GCE) for rapid Cr(VI) determination in water by linear scanning voltammetry (LSV). The Au/UiO-66/GCE showed excellent linearity in the 100 to 1200 ppb Cr(VI) concentration range, with 0.07132 µA/ppb·cm2 sensitivity and a 11.73 ppb detection limit. When potential interfering metals were added, including Cr(III) and Fe(III), the electrochemical detection signal of Cr(VI) did not meaningfully change, suggesting that Au/UiO-66/GCE has good selectivity. A Au/UiO-66/screen printing sensor was also developed for Cr(VI) and used with a portable, handheld electro-analyzer. The Au/UiO-66 nanocomposite—used as an active substrate for electrode modification—was stable, interference-free, and fast, showing promise for the practical determination of Cr(VI) species. [ABSTRACT FROM AUTHOR]

This research theoretically analysed how corporate value is enhanced when Chinese state-owned enterprises (SOEs) shift their focus. In our analysis of Chinese SOEs listed in A-shares from 2013 to 2019, we describe their process of returning to their primary business using the 'three supply and one industry' (3S1I) handover policy. We conducted a quasi-natural experiment to study whether refocusing on SOEs can improve their value. The research shows that the policy enhances the efficiency of SOEs, thus increasing their value. These results were particularly evident among local SOEs. Moreover, SOE employees' social responsibility performance may have a negative moderating effect on efficiency, indicating that excessive social responsibility can lead to a loss in efficiency and a reduction in SOE value. We conclude by discussing why SOEs should prioritize improving economic value and then fulfil social responsibilities to enhance social value through social purchasing and other ways. This study contributes to the literature by providing recommendations on improving the value of SOE from the perspective of 'transferring 3S1I' and refocusing. [ABSTRACT FROM AUTHOR]

This paper considers nonlinear regression models when neither the response variable nor the covariates can be directly observed, but are measured with exponential parametric distortion measurement errors. To estimate parameters in the distortion functions, we propose nonlinear least squares and weighted nonlinear least squares estimation methods under two identifiability conditions. After obtaining calibrated variables, the nonlinear least squares based estimators are proposed to estimate the parameters in the regression model. We studied the asymptotic results of estimators, especially we discuss the difference between the parametric calibrations and nonparametric calibrations. The latter is conducted as if the parametric structures in distortion functions are unknown. Simulation studies demonstrate the performance of the proposed estimators. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a parametric hypothesis test of the multiplicative distortion model under the exponentially distributed but unobserved random variable. The unobservable variable is distorted in a multiplicative fashion by an observed confounding variable. Firstly, some new test statistics are proposed to checking the exponential distribution assumption without distortion effects. Next, we proposed several test statistics when the variable is distorted in the multiplicative fashion. For the latter, the proposed test statistics automatically eliminate the distortion effects involved in the unobserved variable. The proposed test statistics with or without distortions are all asymptotical free, and the asymptotic null distribution of the test statistics are obtained with known asymptotic variances. We conduct Monte Carlo simulation experiments to examine the performance of the proposed test statistics. These methods are applied to analyze four real datasets for illustrations. [ABSTRACT FROM AUTHOR]

During China's reform era, dominant narratives described a transition away from centralised planning in favour of mutually reinforcing processes of liberalisation and decentralisation. Under Xi Jinping, the talk has increasingly been of the recentralisation of authoritarian-state powers and party discipline. Questioning both reform-era transition narratives and equally simplifying claims about their recent reversal, the paper argues for an enriched treatment of party–state spatiality, understood as a polymorphic and multi-scalar process, rather than simply a more complex one. In the emergent Greater Bay Area megaregion, 'new era' zoning strategies are being repurposed as drivers of pathfinding reforms animated by the party–state, in contrast to received readings of zones as single-purpose instruments of liberalisation. [ABSTRACT FROM AUTHOR]

Using a two-solvent interdiffusion technique, the ligand tpatpy that possesses aggregation-induced emission (AIE) properties was coordinated to Cd2+ to construct two coordination polymers under conditions that differed only by reaction temperatures of 30 °C and 0 °C for 1 and 2, respectively. Single-crystal X-ray diffraction studies revealed the key structural differences were that the metal centers in 1 were five-coordinate, versus four-coordinate in 2. Thus, this system could be tuned by controlling the temperature during synthesis. UV-visible spectroscopy (UV-Vis), infrared spectroscopy (IR), powder X-ray diffraction (PXRD), thermogravimetry (TG), and the fluorescence of 1 and 2 are discussed to provide a comprehensive discussion of physical and electronic properties. [ABSTRACT FROM AUTHOR]

The traditional view holds that the dominant deformation mechanism of Ni-based single crystal superalloys at intermediate temperatures (both in tension and creep) is stacking fault shearing γ' phases. Here, we provide direct evidence to prove that the dominant deformation mechanisms of tension and creep are different. The orientation rotation path during tensile at 750 °C has been observed by in-situ electron back-scattered diffraction (EBSD). The result indicates that the dominant mechanism of tensile deformation at intermediate temperature is the movement of matrix dislocations, which is different from the dominant mechanism of the creep process, the stacking fault shearing γ' phases. For the first time, this work reveals the differences in the dominant deformation mechanisms between tension and tensile creep at intermediate temperatures. [ABSTRACT FROM AUTHOR]

A new drimane sesquiterpene 11-methoxyl-danilol (1) was obtained from endophytic fungus Nigrospora chinensis of Gannan navel orange pulp. Its structure was established to possess a natural rarely-occurring tricyclic acetal fused ring system by means of spectroscopic data analyses. Meanwhile, five known compounds danilol (2), redoxcitrinin (3), euphorbol (4), ergosta-7,24(24')-dien-3β-ol (5), and ergosta-4,6,8(14),22-tetraen-3-one (6) were also co-isolated in this fungus. The results of antibacterial and cytotoxic activity screenings showed that compound 5 displayed antibacterial activities against Staphylococcus aureus and MRSA (methicillin-resistant S. aureus) with MIC value of 50 μg/mL. [ABSTRACT FROM AUTHOR]

We consider partial linear regression models when all the variables are measured with additive distortion measurement errors. To eliminate the effect caused by the distortion, we propose the conditional mean calibration to obtain calibrated variables. A profile least squares estimator for the parameter is obtained, associated with its normal approximation based and empirical likelihood based confidence intervals. For the hypothesis testing on parameters, a restricted estimator under the null hypothesis and a test statistic are proposed. A smoothly clipped absolute deviation penalty is employed to select the relevant variables. The resulting penalized estimators are shown to be asymptotically normal and have the oracle property. Lastly, a score-type test statistic is then proposed for checking the validity of partial linear models. Simulation studies demonstrate the performance of our proposed procedure and a real example is analyzed as illustrate its practical usage. [ABSTRACT FROM AUTHOR]

This paper studies the estimation of correlation coefficient between unobserved variables of interest. These unobservable variables are distorted in a new multiplicative fashion by an observed confounding variable, namely, a parametric distortion measurement errors model. The least squares estimation and weighted least squares estimation are used to estimate parameters in the multiplicative distortion functions. An interesting finding is that the calibrated variables obtained by using the weighted least squares estimators perform asymptotic equivalent to the calibrated variables obtained from the nonparametric kernel smoothing estimators in the literature. We then used the calibrated variables to estimate the correlation coefficient, and show that the proposed estimators of correlation coefficient are all asymptotically efficient. Moreover, we suggest an asymptotic normal approximation and an empirical likelihood-based statistic to construct the confidence intervals. We conduct Monte Carlo simulation experiments to examine the performance of the proposed estimators. These methods are applied to analyze two real datasets for an illustration. [ABSTRACT FROM AUTHOR]

We consider the average derivation estimation when neither the response variable nor the covariates can be directly observed, but are measured with multiplicative distortion measurement errors. Three calibration procedures with several estimation methods are used to estimate the average derivation, namely, conditional mean calibration, conditional absolute mean calibration and conditional variance calibration. The asymptotic properties for the estimators are established. Monte Carlo simulation experiments are conducted to examine the performance of the proposed estimators. [ABSTRACT FROM AUTHOR]

The full design of a liquid neutron reflectometer for China spallation neutron source is reported. The horizontal sample geometry enables studies on both solid and liquid samples. A neutron beam with a wavelength range from 1 to 10 Å and neutron flux intensity of 4 × 107 n/cm2/s was optimized for the classical specular reflection. A multi-blade detector with high detection efficiency and a high neutron counting rate was used to ensure the performance of neutron detection. Data acquisition and reduction routines were demonstrated to confirm the reliability of the measurements. The design and algorithms developed in this study pave the way for the future construction of liquid reflectometry for high-performance neutron scattering measurements. [ABSTRACT FROM AUTHOR]

Cemented soil commonly faces issues regarding strength, cracking resistance, and water stability when used in airstrip pavements. Three kinds of soil samples (low-liquid limit clay, high-liquid limit clay, and clayey sand), four kinds of fibers (basalt fiber, glass fiber, fine polypropylene fiber, and coarse polypropylene fiber), and one curing agent (cement) were analyzed in a systematic investigation of the compressive strength of fiber-reinforced cemented soil based on unconfined compressive strength (UCS), water stability, and failure mode. When 38 mm coarse polypropylene fiber at 0.3% content was mixed with 12 mm fine polypropylene fiber at 0.3% content, the hybrid fiber-reinforced cemented soil prepared after 7 d of saturated curing achieved UCS values of 4.18 (low-liquid limit clay), 4.36 (high-liquid limit clay), and 4.16 MPa (clayey sand), which satisfied airstrip requirements for the strength of base course. In this study, coarse polypropylene fiber was adopted and mixed with fine fiber to give full play to their respective advantages and effectively enhance the mechanical properties of cemented soil. The research results improved the understanding of the mechanical properties and reinforcement mechanism of coarse and fine fiber reinforced cemented soil in theory, and enriched the materials and methods of airstrip construction in engineering. [ABSTRACT FROM AUTHOR]

This was a retrospective study that evaluated a total of 280 patients who underwent surgery for complete removal of endometriosis to develop and validate the predictive model for stage IV endometriosis. The differences between stage I-III and stage IV endometriosis were performed by logistic regression. A model for the prediction of stage IV endometriosis was constructed, which was subsequently validated. The independent variables were visual analogue scale (VAS)≥4 [3.855, 95% confidence interval (CI): 1.675–8.871, p = 0.002], painful nodularity on uterosacral ligaments (13.954, 95% CI: 1.658–117.423, p = 0.015), and bilateral endometriosis (5.933, 95% CI: 1.931–18.225, p = 0.002). The AUC of the model was 0.777, with a sensitivity of 71.9% and specificity of 76.3% for stage IV endometriosis. Therefore, a complete collection of patient information prior to surgery, asking about pain and VAS scores, careful completion of pelvic examinations, and application of imaging techniques are conducive to better diagnosis and prediction of advanced endometriosis. What is already known on this subject? Endometriosis, a chronic disease causing pain and infertility, is characterised by endometrial-like tissue outside the uterine cavity, which is often treated via surgery at present. Considering the risks of surgery, it is necessary to identify patients with stage IV endometriosis through non-invasive predictive models for adequate preparation for surgery. However, there is no reliable non-invasive predictive model now, despite utilisation of patient medical history, symptoms especially pain-related ones, pelvic examinations, laboratory examinations, and images in the preoperative diagnosis of endometriosis in the clinic. What do the results of this study add? A model developed based on three simple, accessible and non-invasive indicators displays good performance in predicting stage IV endometriosis. What are the implications of these findings for clinical practice and/or further research? It is conducive to diagnosing and predicting advanced endometriosis before surgery, so as to reduce the difficulty and improve the safety of surgery. [ABSTRACT FROM AUTHOR]

The surface layer of military airfield pavements is prone to damage, including cracking, abrasion, and spalling. It is proposed to strengthen the pavement mortar layer by laying fiber mesh to solve these issues. In this study, three meshes of carbon fiber, aramid fiber, and basalt fiber were selected for surface reinforcement across six pavement slabs of 1.5m (length) × 1.5m (width) × 0.25m (height). The drop hammer impact test was carried out on the six pavement slabs. The test data were analyzed using impact times, crack development characteristics, and development models on the surface deflection as evaluation indices. The results show that the fiber mesh can effectively improve the impact resistance of concrete pavement slabs. Aramid fiber mesh best strengthened the pavement surface, whereas the basalt fiber mesh had the least strengthening effect. However, the mesh size has a negligible influence on the impact resistance of concrete pavement slabs. The effect of fiber mesh on improving the impact resistance of the concrete pavement slab corner was greater than that of the concrete pavement slab edge midpoint. Considering the performance and cost indicators, within the scope of the study, aramid fiber mesh is the most suitable for surface strengthening of airfield concrete pavement. [ABSTRACT FROM AUTHOR]

The family Orchidaceae is renowned for its extensive diversity. Within this family, the genus Goodyera R. Br. is classified under the subtribe Goodyerinae, comprising approximately 99 species. In this study, a species Goodyera yunnanensis Schltr., its plastid genome was characterized. The plastid genome of G. yunnanensis is 146,197 bp in size and exhibits a typical quadripartite structure with a pair of inverted repeat regions (IRs) of 25,611 bp, a large single-copy region (LSC) of 81,300 bp and a small single-copy region (SSC) of 13,675 bp. A total of 126 genes were identified, containing 80 protein-coding genes, 38 tRNA genes and 8 rRNA genes. The overall GC content is 37.2%, with corresponding values of 43.3%, 34.7% and 29.1% in IR, LSC and SSC regions, respectively. Forty-seven simple sequence repeats (SSRs) are found in G. yunnanensis plastome, and the frequency of mononucleotide repeats is significantly higher than other repeat types. Phylogenetic analysis indicates that Goodyera is resolved into four clades. G. yunnanensis belongs to the monophyletic clade A, and its phylogenetic position can be reasonably supported by morphological and molecular data. [ABSTRACT FROM AUTHOR]

Abstract In this article, we study the non parametric estimation of some regression curves when the data are observed with additive distortions, and these distortions for unobservable response variables and covariates are connected with a common observed confounding variable. We study the estimates of the non parametric mean function and its first derivative, the variance function, the Sharpe ratio function, and the correlation curve function. We obtain asymptotic normality results for the proposed non parametric estimators. Monte Carlo simulation experiments are conducted to examine the performance of the proposed estimators. The proposed estimators are applied to analyze a QSAR fish toxicity dataset for illustration. [ABSTRACT FROM AUTHOR]

In marine applications, the scaled wind turbine model (SWTM) based aerodynamic testing apparatus is regarded as one of the most effective approaches to predict the aerodynamic performance of offshore floating wind turbines (OFWTs). To fully disclose the aerodynamics of OFWTs, such kind of apparatus should meet two design requirements: (1) accurate representation of the aerodynamic characteristics of reference wind turbines and (2) reasonable reproduction of the environmental factors from real-world wind-wave-coupled field. Baring with these considerations, the authors propose a cost-effective SWTM-based aerodynamic testing apparatus, which consists of an innovative SWTM, a wind-wave simulator (WWS) and a data acquisition and analyses system. The proposed SWTM is featured by a double-deck tower, which satisfies the requirements of similarity in geometry, stiffness and mass, and a set of redesigned blades. The proposed WWS is capable of simulating both the time-varying inflow wind and the wave-induced platform motions through a wind field generator and a motion simulator. Based on the developed apparatus, a series of aerodynamic tests are conducted to validate the effectiveness of the apparatus design. In addition, the coupling effects of inflow wind and platform motions on the aerodynamics of OFWT are further revealed through experimental tests. [ABSTRACT FROM AUTHOR]

Home- and community-based services (HCBS) may contribute to lowering mortality and enhancing quality of life among older adults. Limited research, however, has examined this relationship in the Chinese context. This study explored the longitudinal association between perceived availability of HCBS and all-cause mortality among Chinese older adults. This cohort study included 8,102 individuals aged 65 years and older from the 2011, 2014, and 2018 waves of the Chinese Longitudinal Healthy Longevity Survey. HCBS included daily life assistance, medical care services, emotional support and social services, and reconciliation and legal aid services. The association between perceived availability of HCBS and all-cause mortality was investigated using Cox proportional hazards models. Emotional support and social services were negatively associated with all-cause mortality (HR = 0.86, 95% CI: 0.78 ~ 0.95, P = .004). Daily life assistance, medical care services, and reconciliation and legal aid services were not significantly associated with all-cause mortality. Providing community-level emotional support and social services may reduce the risk of death. Focusing on the mental health and social well-being of older adults is just as important as caring for their physical health. [ABSTRACT FROM AUTHOR]

The current research examines how risk appraisals of PM2.5 influence Chinese people's behavioral intentions to adopt government-recommended protective behaviors through negative affect. In testing the appraisal-based protective behavior model, this research also takes institutional trust and media sensationalism into account. An online survey is conducted with participants (N = 1,569) randomly drawn from heavily polluted Chinese regions. As predicted, negative affect mediates the effects of perceived susceptibility and perceived severity on individuals' intentions to take preventive measures against the PM2.5 risk. Institutional trust appears to increase people's behavioral intentions. However, media sensationalism decreases people's behavioral intentions. [ABSTRACT FROM AUTHOR]

This article proposes a nonparametric projection-based adaptive-to-model specification test for regressions with discrete and continuous predictors. The test statistic is asymptotically normal under the null hypothesis and omnibus against alternative hypotheses. The test behaves like a locally smoothing test as if the number of continuous predictors was one and can detect the local alternative hypotheses distinct from the null hypothesis at the rate that can be achieved by existing locally smoothing tests for regressions with only one continuous predictor. Because of the model adaptation property, the test can fully use the model structure under the null hypothesis so that the dimensionality problem can be significantly alleviated. A discretization-expectation ordinary least squares estimation approach for partial central subspace in sufficient dimension reduction is developed as a by-product in the test construction. We suggest a residual-based wild bootstrap method to give an approximation by fully using the null model and thus closer to the limiting null distribution than existing bootstrap approximations. We conduct simulation studies to compare it with existing tests and two real data examples for illustration. [ABSTRACT FROM AUTHOR]

This article studies the estimation of correlation coefficient between unobserved variables of interest. These unobservable variables are distorted in both multiplicative and additive fashion by an observed confounding variable. We propose several estimators for the correlation coefficient. Some of estimators are shown to be asymptotically efficient as if there are no distortions in the variables. Moreover, we suggest an asymptotic normal approximation and an empirical likelihood-based statistic to construct the confidence intervals. An improved estimation method for no additive distortion scenario is also considered. We conduct Monte Carlo simulation experiments to examine the performance of the proposed estimators and test statistics. These methods are applied to analyze a real dataset for an illustration. [ABSTRACT FROM AUTHOR]

Organisations widely adopt external monitoring to regulate employees’ cyberloafing, which refers to employees’ non-work-related internet usage during work time. Although prior studies have examined the effect of external monitoring on cyberloafing, the underlying mechanisms through which external monitoring affects cyberloafing remain unclear. Drawing on counteractive control theory and the literature on the relationship between external controls and self-control, we investigate how employees’ self-control can play an important role in understanding the effect of external monitoring on cyberloafing. Based on a survey of 227 employees, we find that external monitoring promotes employees’ self-control motivation, which in turn, decreases their cyberloafing. We further find that the above relationships were contingent upon employees’ dispositional self-control capacity. Our study makes contributions by advancing researchers’ understanding of how external monitoring affects employees’ cyberloafing. Our study also extends the counteractive control theory by introducing the concept of self-control motivation, which is a complementary dimension of self-control capacity. In addition, the findings have important implications for alleviating the potential side effect of external monitoring used in organisations. [ABSTRACT FROM AUTHOR]

Abstract To study the symmetry and asymmetry of the model error under multiplicative distortion measurement errors setting, we propose a correlation coefficient-based measure between the distribution function and the root of density function. The unknown distribution function and density function are estimated from four kinds of residuals: the conditional mean calibration-based residuals, the conditional absolute mean calibration-based residuals, the conditional variance calibration-based residuals, and the conditional absolute logarithmic calibration-based residuals. We study the asymptotic results of the estimators of correlation coefficient-based measure under four calibrations. Next, we consider statistical inference of the correlation coefficient-based measure by using the empirical likelihood method. The empirical likelihood statistics are shown to be an asymptotically standard chi-squared distribution. Simulation studies demonstrate the performance of the proposed estimators and test statistics. A real example is analyzed to illustrate its practical usage. [ABSTRACT FROM AUTHOR]

The fatigue life evaluation of adhesively bonded joints has attracted more and more attention with its extensive application. Here, the fatigue experiments under various loading conditions were carried out to understand the stress amplitude, mean stress, cycle period, and loading path related to the fatigue life of the adhesively bonded tubular butt-joints. The experimental results showed that the fatigue life of the adhesively bonded butt-joint decreased with the increase of stress amplitude and mean stress, and the influence of cycle period on the fatigue life was more obvious since the mechanical property of the selected adhesive was rate dependent. Meanwhile, the fatigue life of the adhesively bonded butt-joint was influenced by the loading path under multiaxial loading conditions. In addition, the relationship between the damage parameters and fatigue life was characterized based on the experimental observations. Accordingly, a stress-based fatigue life prediction model was developed which can simultaneously consider multiple damage parameters related to fatigue life of the adhesively bonded joint. The predicted results indicated that the predicted life correlated well with the experimental data of the adhesively bonded joints. [ABSTRACT FROM AUTHOR]

This paper addresses the integrated optimization of the economic manufacturing quantity and the condition-based maintenance policy of a deteriorating manufacturing system. The considered facility produces a single type of product and is inspected at the end of each production run. Upon inspection, two dependent indicators are revealed: one implies whether the production process is in control or not and the other one represents the deterioration level of the facility. The dependence between the two indicators is that whenever the facility deterioration exceeds a pre-determined level, the system becomes more vulnerable such that the production process may switch to the out-of-control state. In the out-of-control state, a proportion of defective items is fabricated. Considering the inter-dependencies between production process and machine degradation, this paper develops an integrated production and maintenance model to minimize the overall cost. The expected cost rate in the long run is taken as the objective function to assess the proposed model, where the joint optimization of the lot-sizing and the maintenance policy is developed. The problem is formulated in the context of a semi-Markov decision process and solved with the successive approximation method. A numerical example is given to illustrate the applicability of the proposed model. [ABSTRACT FROM AUTHOR]

In this article, the condition-based maintenance optimization of a K-out-of-N deteriorating system considering failure dependence is discussed. The degradation of each component is modelled by a pure jump Lévy process. Whenever one component fails, it can either induce instantaneous failures or lead to the increment of degradation levels of other components. Thus, this model has the flexibility to describe the phenomena of instantaneous failures of multiple components, which is known as the common cause failure. It can also model the accumulative, gradual propagation effect of the component failure to the system. A periodic inspection policy is considered to reveal the real state of the system, upon which, possible maintenance actions can be carried out according to the observations. The inspection and maintenance problem is formulated as a Markov decision process and the value iteration algorithm is employed to solve the problem. The proposed policy is assessed by the total expected discounted cost in the long-run horizon. Under mild conditions, some structural properties of the optimal maintenance policies are obtained. A numerical example is given to illustrate the applicability of the proposed model. It can provide theoretical reference for the decision-maker when developing maintenance policies. [ABSTRACT FROM AUTHOR]

Fifteen compounds including one flavanone hesperitin (1), two cinnamic acid derivatives as (E)-4-hydroxycinnamic acid (2) and (E)-ferulic acid (3), eight polymethoxyflavones (PMFs) (4-11), and four hydroxylated PMFs (12-15) isolated from orange peel were subjected to antibacterial evaluation. Compounds 1-3 exhibited wide-spectrum antibacterial effects against four test strains involving Bacillus subtilis, Staphylococcus aureus, Xanthomonas citri subsp. citri (Xcc), and Meticillin-resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentrations (MICs) ranging from 0.0312 to 0.125 mg/mL. In contrast, all PMFs showed weak antibacterial activity against these four strains with MICs being equal to or more than 0.125 mg/mL. Hydroxylated PMFs demonstrated better antibacterial effect against Xcc relative to PMFs. In addition, the synergistic effect against Xcc was obtained when compounds 1 and 3 were combined. Furthermore, the scanning electron microscopy (SEM) results of Xcc treated with both compounds 2 and 3 showed shrunken and rough surface morphologies, indicative of the cell membrane damage. [ABSTRACT FROM AUTHOR]

We propose a kernel density based estimation for nonlinear regression models when neither the response variable nor the covariates can be directly observed, but are measured with multiplicative distortion measurement errors. For the hypothesis testing of parametric components, restricted estimators under the null hypothesis and test statistics are proposed. The asymptotic properties for the estimators and test statistics are established. A bootstrap procedure is proposed to calculate critical values. Lastly, we make some comparisons between the proposed estimator and nonlinear least squares estimator through the simulation. Our simulation studies indicate that the kernel density based estimator provides a better alternative under some settings, particularly for multimodal distribution of the error term. [ABSTRACT FROM AUTHOR]

Scholars are increasingly calling for a deeper understanding of cyberharassment (CH) with the goal of devising policies, procedures, and technologies to mitigate it. Accordingly, we conducted CH research that (1) integrated social learning theory (SLT) and self-control theory (SCT); (2) empirically studied this model with two contrasting samples, experienced cyberharassers and less experienced cyberharassers; and (3) conducted post hoc tests to tease out the differences between the two samples. We show that for less experienced cyberharassers, CH is largely a social-psychological-technological phenomenon; whereas, for experienced cyberharassers, CH is primarily a psychological-technological phenomenon. Our study makes a threefold contribution: (1) it shows the value of integrating two theories in a holistic and parsimonious manner to explain CH; (2) it shows that SCT alone is a more relevant framework for experienced cyberharassers, whereas a combination of SCT and SLT better explains less experienced cyberharassers; and (3) it reveals that the role of technology in fostering CH is crucial, regardless of the sample. The differential, yet consistent, findings demonstrate that addressing CH is contingent upon not only identifying theoretical approaches but also identifying the particular samples to which these theoretical approaches will be more suitable. Of several implications for practice, the most important may be that anonymity, asynchronicity, and lack of monitoring are the technology choices that foster CH, and thus these should be mitigated in designing social media and other communication technologies [ABSTRACT FROM AUTHOR]

Controlled-release urea (CRU) and normal urea have been shown to improve yield and nitrogen use efficiency (NUE) in rice. However, the effects of combined fertilizers (CRU and normal urea, at different N ratios) on rice yield, temperature and solar radiation utilization efficiency (TSRUE) and NUEs remain unclear. In this study, CRU with release periods of 60 days and 100 days were mixed with urea at N ratios of 7:3, 6:4, 5:5, 4:6 and 3:7 and applied during the rice-growing season in a rice-wheat cropping system. Rice yield, dry matter accumulation (DMA), TSRUE and NUEs were investigated. The yields under one-time fertilization mode 2 (OFM2) and OFM8 were 5.36%-9.70% higher than that of farmer fertilization practices (FFP) on average across 2018 and 2019. The NUEs under OFM2 and OFM8 was 3.87%-35.56% and 6.26%-58.56% higher than that under FFP, respectively, across 2018 and 2019. Correlation analysis showed that TSRUE were significantly positively correlated with yield, DMA and NUEs. The higher TSRUE under OFM2 and OFM8 contributed to the synergistic improvement of yield and NUEs. Both OFM2 and OFM8 improved rice yields and NUEs compared to FFP while having lower fertilizer and labor costs; therefore, these treatments are worthy of promotion and application. [ABSTRACT FROM AUTHOR]

Enriched environment (EE) is an important animal experimental paradigm to decipher gene-environment interaction. It is thought to be efficient in aiding recovery from certain metabolism disorders or cognitive impairments. Recently, the effects of EE during adolescence in mice gradually draw much attention. We first established an EE model in adolescent mice, dissected lipid metabolism, and further examined baseline level of anxiety and depression by multiple behavioral tests, including open field test (OFT), elevated zero maze (EZM), tail suspension test (TST), and forced swimming test (FST). EE mice exhibited lower weights, lower cholesterol than standard housing (SH) mice. Behaviorally, EE mice traveled more distance and had higher velocity than SH mice in OFT and EZM. Besides, EE mice showed reduced anxiety levels in OFT and EZM. Furthermore, EE mice also had less immobility time than SH mice in TST and FST. Thus, these results suggest that EE during adolescence has metabolic and behavioral benefits in mice. [ABSTRACT FROM AUTHOR]

Metal hydrides are used as additives to improve the reaction energy and destructive effect of PTFE/Al system. PTFE/Al/TiH2, PTFE/Al/MgH2 and PTFE/Al/ZrH2 are fabricated to compare the effect of multi-metal-hydrides on the material properties. The mechanical response of the materials at wide range of strain rates are investigated through conducting the quasi-static compression tests and split-Hopkinson pressure bar tests. The reaction energy, reaction mechanism, and damage effect are systematically studied by performing oxygen bomb calorimeter measurements, drop-weight experiments, and energetic liners impact damage experiments. The results show that adding TiH2 and ZrH2 with 10 wt% content can improve the strength and toughness of PTFE/Al, while MgH2 plays a negative role in enhancing the mechanical property. MgH2 has the strongest energy enhancement effect and energy release rate. TiH2 is the most effective additive in prolonging the reaction time and enhancing the target reaming effect because of its highest gas production rate. [ABSTRACT FROM AUTHOR]

To investigate the impact of shock index before Intra-Aortic Balloon Pump (IABP) implantation on recent prognosis of patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI) underwent primary percutaneous coronary intervention (PCI). A total of 103 patients with CS complicating AMI admitted in our hospital from June 2014 to May 2019 who underwent primary PCI with IABP support were enrolled in the study. We collected the data according to the medical records and collected their clinical manifestation and laboratory examination, as well as 28-day mortality, and also calculated the shock index (ratio of heart rate to systolic blood pressure) before IABP implantation. Patients with higher SI at IABP insertion were associated with higher proportion of anterior infarction (81.5% vs. 61.2%, p = 0.022), previous history of PCI (24.1% vs. 8.16%, p = 0.030), culprit leision at left main (31.5% vs. 12.2%, p = 0.019), and final TIMI flow ≤ 2(55.5% vs. 26.5%, p = 0.003), invasive ventilation(40.7% vs. 20.4%, p = 0.026) as well as 28-day-mortality (81.5% vs. 61.2%, p = 0.022). SI at insertion may help predict recent outcome, with a cutoff value of 1.625, a sensitivity of 0.655 and a specificity of 0.708, and areas under the receiver-operating characteristic curve (AUCROC) was 0.713. On multiple analysis, SI, together with final TIMI flow, arterial pH and creatinine were independent predictive factors of recent prognosis among this population. Among CS patients complicating AMI undergoing PCI with the support of IABP, higher SI before IABP implantation was associated with poorer prognosis, SI was an independent risk factor of 28-day mortality and may predict the 28-day outcome. [ABSTRACT FROM AUTHOR]