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In this study, we employed the non-uniform rational B-splines surface technique to develop a provisional horizontal wind model of the mesosphere and lower thermosphere at altitudes of 87, 97, and 250 km over Kelan (38.7°N, 111.6°E) in China using Fabry–Perot interferometer (FPI) observations for the period between January 2012 and May 2014. We compared the meridional and zonal winds derived from the Kelan FPI wind model with those based on Meteor Radar wind observations at Beijing (39.92°N, 116.39°E), and those calculated from horizontal wind models, i.e., HWM93 and HWM07, at Kelan. Our analysis showed the following. (1) At 87 and 97 km, the Kelan FPI wind patterns exhibited strong annual variation in the meridional wind and semiannual variation in the zonal wind, as well as diurnal variation, which was dominated by a semidiurnal tidal variation in the meridional and zonal winds during May and September with a diurnal phase difference. The Kelan FPI wind patterns agreed well with the Meteor Radar winds and the HWM07 model results, but less well with the HWM93 model. (2) At 250 km, the FPI wind patterns agreed fairly well with the HWM93 results, where both indicated annual/diurnal variation in the meridional and zonal winds, and weak semidiurnal tidal variation. There were large discrepancies between the Kelan FPI winds and the HWM07 model results, which were mainly due to differences in the annual variation in the nighttime meridional wind. (3) The magnitude of the FPI winds was comparable to the HWM93 results but they were nearly 40–50% lower than the other winds, which is attributable to the inherent limitations of airglow measurement. Thus, this local empirical wind model could be used to investigate the climatological features of local ionospheric spatial–temporal variations. [ABSTRACT FROM AUTHOR]

Land surface temperature (LST) plays a crucial role in characterizing land surface processes and the energy balance. Accurate monitoring of spatial–temporal variations in LST holds great significance for global and regional climate change research. However, with the increasing of multi-source remote sensing data, it has become a challenging task to construct an LST model that reduces dependence on auxiliary data (such as land surface emissivity (LSE) and atmospheric water vapor content (WVC) synchronized with satellite observations. This study proposed an LST retrieval model based on random forest model (RFLSTR). The results of 10-fold cross-validation showed that the RFLSTR model had high modelling accuracy, the root mean square error (RMSE) and mean absolute error (MAE) were lower than 2 K. Landsat 8 images from the Beijing area and South Korea, were utilized to assess the spatial–temporal migration performance of the RFLSTR model. Additionally, Landsat 9 images from South Korea were employed to analyse the sensor migration performance of the RFLSTR model. In conclusion, the findings highlight that the proposed RFLSTR model achieve high retrieval accuracy without relying on auxiliary data (such as LSE and WVC) synchronized with satellite observations. Moreover, the RFLSTR model exhibits robust spatial–temporal capabilities, enhancing the efficiency of LST retrieval and facilitating the utilization of satellite data. [ABSTRACT FROM AUTHOR]

PURPOSE. This study aimed to determine the rate of falls and their relationship with sociodemographic and clinical factors in a psychiatric institution in Beijing, China. DESIGN AND METHODS. The case notes of 7,921 inpatients were scrutinized to identify patients who fell while in the hospital. FINDINGS. The fall rate in this study was 1.2% of all inpatients. Nearly all (89.7%) falls occurred when patients attempted to stand up, get out of bed, or walk. PRACTICE IMPLICATIONS. Effective measures should be provided to prevent falls in psychiatric wards. A prospective study exploring predictors of falls is warranted. [ABSTRACT FROM AUTHOR]

Background: The study aimed to determine the prevalence of alcohol use, episodic heavy drinking, and alcohol dependence and their socio-demographic correlates in Beijing, China. Methods: A total of 5,926 subjects were randomly selected in Beijing and interviewed using the Composite International Diagnostic Interview (CIDI 1.0). Data on basic socio-demographic and current major medical conditions were also collected. Results: The 12-month prevalence of alcohol use and episodic heavy drinking were 32.5 and 13.8%, respectively. The 12-month and lifetime prevalence of alcohol dependence were 1.7 and 4.3%, respectively. Age above 24 years, male sex, being married and employed, low education level (junior high school, primary school or illiterate), rural residence, and having comorbid psychiatric disorders were all significantly associated with a higher likelihood of alcohol-related disorders. Only 2.4% of the subjects with alcohol dependence were receiving treatment, and a mere 1.4% had sought treatment from mental health professionals. Conclusions: Nationwide surveys are urgently needed to further explore the prevalence of alcohol-related disorders in China. [ABSTRACT FROM AUTHOR]

Abstract: Objective: This study aimed to determine the 12-month and lifetime prevalence of major depressive episode (MDE) and their socio-demographic correlates in both the urban and rural areas of Beijing, China. Methods: A total of 4767 adults were randomly selected and interviewed in Beijing using the Composite International Diagnostic Interview (CIDI 1.0). Basic socio-demographic and clinical data were collected during the interviews. Results: The overall 12-month prevalence of MDE was 3.2%; 2.8% and 3.8% for men and women, respectively. The overall lifetime prevalence of MDE was 5.3%; 4.4% and 6.3% for men and women, respectively. Being older than 25 years of age was independently associated with increased risk of MDE. Sixteen point three percent of the subjects with lifetime MDE attempted suicide while the rate of suicide attempts was only 0.2% in subjects without MDE. The percentage of subjects with MDE who received any type of treatment from medical practitioners was 33.1%; of them, only 5.4% sought help from mental health professionals. Conclusions: National epidemiologic surveys are needed to further explore the prevalence of MDE in China. The low percentage of subjects treated for MDE constitutes a major public health problem that should be urgently addressed. [Copyright &y& Elsevier]

Abstract: Background: In China, there is limited information on smoking and its socio-demographic correlates in general, and in psychiatric patients in particular. The aim of this study was to determine the prevalence of lifetime, current mild, and heavy smoking, the socio-demographic correlates of current smoking, and its relationship with psychiatric disorders in the Beijing municipality, China. Methods: A total of 5926 subjects who met the study''s entry criteria were randomly selected from the urban and rural areas of Beijing and interviewed using standardized assessment tools, including the collection of basic socio-demographic and clinical data. All subjects fully cooperated in the interviews and readily disclosed all of the information. Results: The prevalence of lifetime smoking was 35.9%; the rates for current mild and heavy smoking were 21.8% and 10.8%, respectively. An age of 24 years or above, male sex, married, divorced, separated or widowed marital status, relatively low level of education (less than college level), being employed, a relatively high monthly income (more than RMB500), rural abode, and having a psychiatric disorder were risk factors of current smoking. Both current mild and heavy smoking were significantly associated with alcohol dependence, and current heavy smoking was also associated with a history of a major depressive episode. Conclusions: The prevalence of smoking in the rural and urban areas of Beijing is unacceptably high. In addition to certain socio-demographic factors, smoking was associated with common psychiatric disorders. Nationwide surveys are warranted to further explore the prevalence of smoking in China. Effective strategies to reduce the high rate of smoking are also needed. [Copyright &y& Elsevier]

Objective: There has been no large-scale survey of suicide-related behaviours including suicidal ideations, plans and attempts in China involving both rural and urban areas and using standardized assessment tools. The aim of the present study was to determine the lifetime prevalence of suicide-related behaviour and its relationship with sociodemographic factors and psychiatric disorders in the rural and urban regions of Beijing, China. Methods: A total of 5926 subjects were randomly selected in Beijing and interviewed using the Composite International Diagnostic Interview. Basic sociodemographic and clinical data and data on suicide-related behaviour were also collected. Results: The overall lifetime prevalence estimates of suicidal ideation, plans and attempts were 2.3%, 1.4%, and 1.0%, respectively; the corresponding figures were 2.8%, 1.6%, and 1.3% in the rural sample, and 1.8%, 1.3%, and 0.9% in the urban sample. Age (>25years), female sex, unmarried status, lower education level, lower (RMB2000month-1) monthly income and presence of major medical disorders were significantly associated with increased risk of suicide-related behaviour. 36.2% of subjects with suicide-related behavior consulted a medical practitioner and 20.7% consulted a psychiatrist. Conclusions: The prevalence of lifetime suicide-related behaviour in Beijing is lower than in Western countries, but the low percentage of subjects treated for suicide-related behaviour indicates a major public health problem that should be addressed. National surveys are needed to further explore the prevalence of suicide-related behaviour in China. [ABSTRACT FROM AUTHOR]

This study compared the subjective quality of life (SQOL) in schizophrenia patients living with their families in Hong Kong (HK) and Beijing (BJ) and explored the relationship between SQOL and basic socio-demographic and clinical factors. Two hundred and sixty-four clinically stable outpatients with schizophrenia were randomly selected in HK and 258 counterparts matched according to age, sex, age at onset, and length of illness in BJ. SQOL and psychiatric status were assessed with standard rating instruments. There was no significant difference in any of SQOL domains between the two cohorts after controlling for potentially confounding variables. Positive, depressive and anxiety symptoms and drug-induced extrapyramidal side effects (EPS) were all significantly correlated with SQOL. Multiple regression analysis revealed that only depressive symptoms predicted all SQOL domains in both groups. Having removed depressive symptoms from the model, positive symptoms predicted all domains, anxiety predicted all but social domains, use of benzodiazepines (BZD) predicted all but physical domains, EPS predicted physical domain, and history of suicide predicted social domain in HK; anxiety predicted all domains, positive symptoms predicted all but physical domains, EPS, use of BZD and history of suicide all predicted physical domains, and length of illness predicted environmental domain in BJ. Despite considerable differences between the two sites in terms of health care delivery and the economic conditions of the subjects, SQOL did not differ between HK and BJ. The conclusion is in line with previous studies that suggested that patients’ SQOL was independent of their living standard as long as it reached a certain minimum level. SQOL was more strongly related to the severity of depressive symptoms and had weak association with socio-demographic factors. [ABSTRACT FROM AUTHOR]

Objectives: By analyzing the distribution of existing and newly proposed staging imaging features in pT1–3 and pT4a tumors, we searched for a salient feature and validated its diagnostic performance. Methods: Preoperative multiphase contrast-enhanced CT images of the training cohort were retrospectively collected at three centers from January 2016 to December 2017. We used the chi-square test to analyze the distribution of several stage-related imaging features in pT1–3 and pT4a tumors, including small arteriole sign (SAS), outer edge of the intestine, tumor invasion range, and peritumoral adipose tissue. Preoperative multiphase contrast-enhanced CT images of the validation cohort were retrospectively collected at Beijing Cancer Hospital from January 2018 to December 2018. The diagnostic performance of the selected imaging feature, including accuracy, sensitivity, and specificity, was validated and compared with the conventional clinical tumor stage (cT) by the McNemar test. Results: In the training cohort, a total of 268 patients were enrolled, and only SAS was significantly different between pT1–3 and pT4a tumors. The accuracy, sensitivity, and specificity of the SAS and conventional cT in differentiating T1–3 and T4a tumors were 94.4%, 81.6%, and 97.3% and 53.7%, 32.7%, and 58.4%, respectively (all p < 0.001). In the validation cohort, a total of 135 patients were collected. The accuracy, sensitivity, and specificity of the SAS and the conventional cT were 93.3%, 76.2%, and 96.5% and 62.2%, 38.1%, and 66.7%, respectively (p < 0.001, p = 0.021, p < 0.001). Conclusion: Small arteriole sign positivity, an indirect imaging feature of serosa invasion, may improve the accuracy of identifying T4a colon cancer. Clinical relevance statement: Small arteriole sign helps to distinguish T1–3 and T4a colon cancer and further improves the accuracy of preoperative CT staging of colon cancer. Key Points: • The accuracy of preoperative CT staging of colon cancer is not ideal, especially for T4a tumors. • Small arteriole sign (SAS) is a newly defined imaging feature that shows the appearance of tumor-supplying arterioles at the site where they penetrate the intestine wall. • SAS is an indirect imaging marker of tumor invasion into the serosa with a great value in distinguishing between T1–3 and T4a colon cancer. [ABSTRACT FROM AUTHOR]

The pace of urbanization in China has increased in recent decades. Accordingly, the urbanized area has expanded at a spectacular rate and the urban heat island (UHI) has intensified. Understanding the effects of the landscape pattern on the UHI is crucial for optimizing urban structure, which could mitigate the UHI. This study focused on green cover in an urban area. To investigate how the composition and configuration of urban green patches would affect their temperature in Beijing metropolitan region, China, especially the influence of the configuration of green patches on their cooling effect, the relationships between green surface temperature (GST), normalized difference vegetation index (NDVI), and normalized compactness index (NCI) were investigated by regression analyses, and a method to quantify the cooling effect of greens derived from the urban cool island and green space cool island was proposed. The image from the Landsat Thermal Infrared Sensor was used to estimate GST, and three images from the GF-2 Panchromatic & Multispectral Camera were used to obtain NDVI and calculate NCI. Our results showed that both NDVI and NCI had negative relationships to GST in summer, but only NCI strongly influenced the spatial cooling effect of greens. The further exploration of the influence of NCI on the cooling effect showed the NCI was negatively correlated to the cooling effect, which indicated that, for a given area, more compact green patches reduce the extent of the cooling effect. [ABSTRACT FROM AUTHOR]

Objective: Aggression is common and challenging in psychiatric emergency departments (PED). However, the prevalence of aggression and its correlates in PED patients are not well documented. This study compared the prevalence of aggression between patients with acute schizophrenia and manic episodes.Methods: In this cross-sectional study, patients at a psychiatric emergency department were assessed with measurements of aggression, psychotic and manic symptoms.Results: A total of 4,172 patients were included. The prevalence of aggression was 54.8% (95%CI=53.3%-65.2%) in the whole sample, with 48.0% (95%CI=45.8%-50.1%) in patients with an acute schizophrenia episode, and 61.8% (95%CI=59.8%-63.9%) in patients with a manic episode. Multiple logistic regression analysis revealed that, within the acute schizophrenia episode group, male gender (OR=1.47, P<0.01), involuntary admission (OR=3.61, P<0.01) and more severe manic symptoms (OR=1.30, P<0.01) were significantly associated with aggression. Within the manic episode group, living in Beijing (OR=1.51, P<0.01), unemployment (OR=1.34, P=0.03), involuntary admission (OR=7.93, P<0.01), lower education (OR=0.95, P=0.01) and more severe psychotic symptoms (OR=1.05, P<0.01) were significantly associated with aggression.Conclusion: In this study, aggression appeared to be more common among patients with a manic episode than those with an acute schizophrenia episode. Considering the significant risk of aggression on psychiatric emergency care, appropriate and effective management of aggression in this population group need to be developed. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence and aerosol scattering can produce the blurring of the remotely sensed image. The degrading effect is usually quantified by atmospheric modulation transfer function (MTF). However, this effect behaves differently with different remote sensors. The effort of this article is to study the different degrading effects of aerosol MTF and turbulence MTF between charge-coupled device (CCD) camera on China–Brazil Earth Resources Satellite-02b (CBERS-02b) and on Huan Jing-1A/1B satellite (HJ-1A/1B). Specifically, a corrected aerosol MTF model is established based on classical solution of small-angle approximation (SAA) model by considering the MTF and the effective instantaneous field of view (EIFOV) of CCD cameras. By assuming many different atmospheric conditions, the aerosol MTF and turbulence MTF for two CCD cameras are evaluated. It is found that the output aerosol MTF of CCD camera on HJ-1A/1B causes more degrading effect than that of CBERS-02b under the same atmospheric condition. However, the situation reverses for the turbulence MTF. Furthermore, CCD images acquired over Beijing, China, by CBERS-02b and HJ-1A/1B on four different dates are selected. The overall atmospheric MTF for these images are determined based on the aerosol products from Aerosol Robotic Network (Aeronet) and radiosounding data. Results indicate that the overall atmospheric MTF of CBERS-02b CCD camera reduces image quality more seriously than that of HJ-1A/1B CCD camera. Additionally, the atmospheric MTF compensation is performed and evaluated for these CCD images based on the overall atmospheric MTF. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is widely known with a high incidence rate worldwide, but the correlation between exposure to per- and polyfluoroalkyl substances (PFAS) and the number of lymph nodes in CRC patients remains unclear. In the present study, we enrolled 305 CRC patients (122 females and 183 males) at Beijing Hospital in China. A total of 17 PFAS were detected in serum samples of these patients, and 5 PFAS with detection rates >75% were selected in this study. The CRC patients' number of metastatic lymph nodes (MLNs) and total lymph nodes (TLNs) were chosen as outcomes. Poisson regression models were used to analyze the associations between single PFAS and number of MLNs and TLNs. Quantile g-Computation models were performed to examine the joint effect of PFAS mixtures on number of MLNs and TLNs. A positive correlation between serum PFAS levels and number of MLNs was identified. For instance, the numbers of MLNs in patients with serum PFOA, PFNA, 6:2 Cl-PFESA concentrations at the 95th percentile were 27% (95% CI: 1%, 60%), 35% (95% CI: 1%, 82%), 87% (95% CI: 4%, 238%) higher compared with the threshold level. The results of Quantile g-Computation models also showed that every quantile increase in PFAS mixtures was associated with a 4.67%, (95% CI: 0.07%, 9.48%) increase in the numbers of MLNs, and PFOS dominated the effects of the mixtures. Moreover, a negative correlation between PFAS mixtures and number of TLNs in patients with no MLNs was also observed. The present study suggested that exposure to PFAS may worsen the prognosis of CRC patients. These findings could help guide future research and public health policies aimed at reducing exposure to PFAS and mitigating their potential impacts on human health. [Display omitted] • Five of the 17 PFAS were frequently detected in serum of 305 colorectal cancer patients. • Higher PFAS mixtures were associated with elevated number of metastatic lymph nodes. • PFOS dominated the effects of the PFAS mixtures on number of metastatic lymph nodes. [ABSTRACT FROM AUTHOR]

Household cooking and space heating with biomass and coal have adverse impacts on both indoor and outdoor air quality and are associated with a significant health burden. Though household heating with biomass and coal is common in northern China, the contribution of space heating to ambient air pollution is not well studied. We investigated the impact of space heating on ambient air pollution in a village 40 km southwest of central Beijing during the winter heating season, from January to March 2013. Ambient PM 2.5 concentrations and meteorological conditions were measured continuously at rooftop sites in the village during two winter months in 2013. The use of coal- and biomass-burning cookstoves and space heating devices was measured over time with Stove Use Monitors (SUMs) in 33 households and was coupled with fuel consumption data from household surveys to estimate hourly household PM 2.5 emissions from cooking and space heating over the same period. We developed a multivariate linear regression model to assess the relationship between household PM 2.5 emissions and the hourly average ambient PM 2.5 concentration, and a time series autoregressive integrated moving average (ARIMA) regression model to account for autocorrelation. During the heating season, the average hourly ambient PM 2.5 concentration was 139 ± 107 μg/m 3 (mean ± SD) with strong autocorrelation in hourly concentration. The average primary PM 2.5 emission per hour from village household space heating was 0.736 ± 0.138 kg/hour. The linear multivariate regression model indicated that during the heating season – after adjusting for meteorological effects – 39% (95% CI: 26%, 54%) of hourly averaged ambient PM 2.5 was associated with household space heating emissions from the previous hour. Our study suggests that a comprehensive pollution control strategy for northern China, including Beijing, should address uncontrolled emissions from household solid fuel combustion in surrounding areas, particularly during the winter heating season. [ABSTRACT FROM AUTHOR]

Abstract: Aerosol Robotic Network (AERONET) aerosol optical depth (AOD) and almucantar retrievals (single scattering albedo (SSA) and aerosol size distribution) from 2005–2009 in Beijing and Kanpur are used to analyze differences and similarities in aerosol optical properties over these two regions. The examination of monthly mean AOD (440 nm) shows that maximum and minimum values occurred in summer and winter, respectively, for Beijing, while the range in AOD in Kanpur was lower. Precipitation in both Beijing and Kanpur peaked in summer; however, the columnar water vapor (CWV) exhibited a high correlation with AOD in Beijing (R 2 = 0.79) but had a weak relationship with AOD in Kanpur (R 2 = 0.13). The Angstrom exponent (α, 440–870 nm) generally increased linearly as the fine mode fraction (FMF) of AOD (500 nm) increased for FMF < 90% in both regions, with a high correlation of R 2 > 0.96. However a clear decrease in α for FMF > 90% found in Beijing is not shown distinctly in Kanpur, and is mainly due to the higher aerosol loading in this FMF bin at Beijing (AOD at 440 nm > 2.2) which results in a stronger coagulation of fine mode particles. Bimodal seasonally-averaged size distributions reveals similar aerosol mixtures composed of fine pollution particles and coarse dust particles in both regions. The analysis of spectral SSA as a function of α is emphasized in this paper. The average SSA at 440 nm in both regions shows a similar low dynamic range of ∼0.03 for α < 1.4. The obvious increase in SSA at 440 nm for α > 1.4 in both regions can be attributed to a higher FMF leading to fine mode coagulation. However, the distinctly smaller increase in Kanpur suggests that fine mode aerosols at Beijing are less absorbing than those at Kanpur. The visibly lower SSA at 675 nm at Kanpur compared to that at Beijing for α > 0.4 is due to a larger find-coarse mode separation radius of ∼0.76 μm in Beijing versus a value lower than ∼0.58 μm in Kanpur. Another reason lies in the weaker absorption by fine mode aerosols in Beijing. The distinctly lower near-infrared SSA in Kanpur when α < 1.4, compared to Beijing, may be attributed to lower aerosol concentrations in all α bins, resulting in less aggregation of absorbing black carbon particles on coarse particles in Kanpur. The classification of aerosol properties shows that the AOD accumulation mode in all seasons, even including spring, in Beijing and in post-monsoon and winter seasons in Kanpur can be attributed to fine particle coagulation or hygroscopic growth; during pre-monsoon and monsoon seasons in Kanpur, it is due to coarse mode particle accumulation or cloud contamination. [Copyright &y& Elsevier]