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Background: As the phenomenon of ageing continues to intensify, home and community-based services (HCBSs) have been increasingly important in China. However, the association between HCBSs utilization and depressive symptoms in older adults in China is unclear. Consequently, this study aimed to examine the association between HCBSs utilization and depressive symptoms in Chinese older adults. Methods: This study included 7,787 older adults (≥ 60 years old) who were recruited within the framework of the 2018 China Health and Retirement Longitudinal Study (CHARLS). Depressive symptoms were assessed using the 10-item Center for Epidemiological Studies Depression Scale (CES-D-10). HCBSs utilization was assessed via the question, "What kind of HCBSs were being utilized in their community?". Data were analyzed using binary logistic regression models and generalized hierarchical linear models (GHLM). Results: Of the 7,787 participants, 20.0% (n = 1,556) reported that they utilized HCBSs, and 36.7% (n = 2,859) were evaluated that they had depressive symptoms. After adjusting for individual- and province-level covariates, the HCBSs utilization was found to be associated with depressive symptoms (OR = 1.180, 95% CI: 1.035–1.346, p < 0.05). Additionally, the depressive symptoms were significantly associated with gender, residence, educational level, marital status, number of chronic diseases, self-rated health (SRH), smoking, and provincial Gross Domestic Product (GDP) per capita. Conclusions: This study found HCBSs utilization might be a protective factor against depressive symptoms in Chinese older adults. It is of utmost significance for the government to provide targeted HCBSs at the community level to address the unmet care needs of older adults, which can reduce the occurrence of negative emotions, consequently contributing to less severe depressive symptoms. [ABSTRACT FROM AUTHOR]

The most difficult problem for the control of heavy-haul trains is the cyclic air braking on long steep downward slopes. Unsuitable positions of the application of air braking will cause large longitudinal impulses, overspeeding and even accidents. This article proposes a mixed-integer linear programming (MILP) approach to the optimization of the speed curve of heavy-haul trains. First, with the objectives of maximizing the operation distance and minimizing the air braking time within a given period, an optimization model of a heavy-haul train is formulated considering multiple practical constraints, such as the speed limit, release time and releasing speed. Second, the optimization problem is transformed into an MILP problem by linearizing the nonlinear conditions, and is solved with existing CPLEX ® solvers. Finally, some case studies are conducted with actual data from the Shuohuang railway in China to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The Erlian basin is one of the most important basins in northern China to host sandstone-type uranium deposits (SUDs), in which Bayanwula, Saihangaobi, and Hadatu are under development, to name a few. Issues such as the metallogenic mechanism and mineralization of these deposits need to be addressed throughout the mining process. Over the past several decades, 2D and 3D seismic reflection surveys have been carried out to study these typical SUDs. The seismic technique has become the most effective geophysical tool of uranium (U) exploration, and it is used to develop our understanding of the stratigraphic configuration, faults, and sandstone contents of target layers in uranium environments. In addition, seismic interpretation could yield useful suggestions regarding the subsequent drilling program in the work area. There are two seismically predictable patterns of SUDs, named "Big depression + fault" and "Large-angle unconformity + fault", which have been established following detailed seismic research in this basin. The characteristics of these faults are as follows: (1) the "'U'-shaped formation" is conducive to the inflow of O-U-bearing groundwater into the target sandstone; (2) the "Big depression of reductive formation" provides plenty of organic matter (containing reducing media and U pre-enrichment) to promote redox reaction mineralization; (3) "Large-angle unconformity" is favorable to the migration of reducing substances, consequently leading to an enhancement in redox U mineralization; (4) "faults with long-term activity" become rising channels for reducing the presence of fluids and gases at depth; and (5) "sandstone and its scrambled seismic facies". The results also offer indirect evidence of a connection between hydrothermal fluids and U mineralization; a hypothesis of "hydrothermal effusion" mineralization is proposed accordingly. In conclusion, seismically produced images of geological structures and sandstone distribution could yield important information for U prospecting and mine planning; it is worth considering seismic technologies in the future exploration of SUDs. [ABSTRACT FROM AUTHOR]

The primary exploration objective of Qiharigetu Sandstone-type Uranium (SU) deposit in the Erenhot Basin of China is to understand the stratigraphy, lithology and fault distribution of the target layer. Various geophysical techniques including gravity, magnetic, electromagnetic and 2D seismic have been proved not very effective due to its shallow depth of burial and small geophysical differences between layers. A specific 3D seismic survey of the Qiharigetu SU deposit has been carried out, and the inferred geological features of the uranium mineralization could provide important references for subsequent drilling programs. It is deduced that the target layer in the central part of the study area has a local "depression" through 3D seismic imaging and interpretation, which is conducive to river runoff and formation of sand body, as the sand body is a necessary precondition for mineralization. There are faults (5–50 m in throw) striking north–south for around 2 km, and it is an important ore-controlling factor, which could provide channels for the rise of reducing agents (such as gas, H2S, and coalbed methane) at depth as they can promote the redox reaction for mineralization. The 3D seismic inversion is used to estimate the impedance, lithology, sand content and porosity of the target layer. With the help of drilling verification, it is found that the area with sand content over 75% and porosity over 10% is favorable for the SU deposit. Compared with other geophysical techniques, 3D seismic method is able to provide high-resolution images for unraveling SU mineralization and thereby reduce the drilling risk of the SU deposit. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus 1 (PRRSV1) and 2 (PRRSV2) (including 3 major subtypes: classical (CA‐PRRSV2), highly pathogenic (HP‐PRRSV2) and NADC30‐like (NL‐PRRSV2)) are currently coexisting in Chinese swine herds but with distinct virulence. Reliable detection and differentiation assays are crucial to monitor the prevalence of PRRSV and to adopt effective control strategies. However, current diagnostic methods cannot simultaneously differentiate the four major groups of PRRSV in China. In this study, universal and quadruplex real‐time RT‐PCR assays using TaqMan‐MGB probes were developed for simultaneous detection and differentiation of Chinese PRRSV isolates. The newly developed real‐time RT‐PCR assays exhibited good specificity, sensitivity, repeatability and reproducibility. In addition, the newly developed real‐time RT‐PCR assays were further validated by comparing with a universal PRRSV conventional RT‐PCR assay on the detection of 664 clinical samples collected from 2016 to 2019 in China. Based on the clinical performance, the agreements between the universal and quadruplex real‐time RT‐PCR assays and the conventional RT‐PCR assay were 99.55% and 99.40%, respectively. Totally 90 samples were detected as PRRSV‐positive, including 2 samples that were determined to be co‐infected with NL‐PRRSV2 and HP‐PRRSV2 isolates by the quadruplex real‐time RT‐PCR assay. ORF5 sequencing confirmed the real‐time RT‐PCR results that 2, 6, 27 and 57 of the 92 sequences were PRRSV1, CA‐PRRSV2, NL‐PRRSV2 and HP‐PRRSV2, respectively. This study provides promising alternative tools for simultaneous detection and differentiation of PRRSV circulating in Chinese swine herds. [ABSTRACT FROM AUTHOR]

Abstract Classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circoviruses (PCV2 and PCV3) are economically important swine viruses that cause reproductive failure and/or respiratory symptoms in pigs. However, the co-infection status of these viruses in Chinese swine herds is not well clarified. In this study, we evaluated the co-infection of these four viruses in 159 pigs collected from 63 herds in eight regions of China from 2016 to 2018. CSFV, PRRSV, PCV2 and PCV3 were detected in 14, 56, 43 and 4 of the pigs, respectively. The percentage of singular infections was 32.71%, while the percentages of dual infections and multiple infections were 15.72% and 3.15%, respectively. The E2 of CSFV, ORF5 of PRRSV, ORF2s of PCV2 and PCV3 from all positive samples were determined and used for phylogenetic analyses. E2-based phylogenetic tree showed that all 14 CSFVs identified in this study belong to 2.1b subtype. ORF5-based phylogenetic tree showed that PRRSV2 is predominant in China while PRRSV1 can also be detected. In addition, 35, 16, 4 and 1 of our PRRSVs are clustered with highly pathogenic PRRSV2, NADC30-like PRRSV2, classical PRRSV2 and PRRSV1, respectively. ORF2-based phylogenetic trees showed that our PCVs are grouped with 2 PCV2 subtypes (PCV2d and PCV2b) and 3 PCV3 subtypes (PCV3a, PCV3b and PCV3c), respectively. Our results provide the latest co-infection status and the diversity of four important swine viruses in Chinese swine herds, which is beneficial for understanding the epidemiology of these viruses. Highlights • The co-infection status of CSFV, PRRSV, PCV2 and PCV3 in eight regions of China was determined. • Both singular infections and different patterns of co-infections were observed. • The diversity of these four viruses was also evaluated by phylogenetic analyses. [ABSTRACT FROM AUTHOR]

With the development of economy and urbanization, the natural gravels and sands for new road construction materials encountered severe shortage issues in recent decades. In the meantime, the municipal Solid Waste Incineration bottom ash (MSWIBA) is regarded as a feasible alternative of mined nature aggregates due to its similar mineralogical, physical and chemical characteristics. However, the uncertainties of long-term service performance and potential environmental pollution risk of MSWIBA prevent its widespread applications in road constructions. For these reasons, this paper investigates the resilient modulus and permanent deformation properties by the repeated load triaxial test at different moisture contents, and examines the long-term environment influence using leaching tests on the samples after subjecting to 5 freeze-thaw cycles and samples after one year weathering. Besides, the existing resilient modulus and permanent deformation prediction models of unbounded granular materials are evaluated for their applicability on MSWIBA. The test results indicate that the MSWIBA shows obvious stress-dependence and moisture-dependence in resilient modulus and permanent deformation behaviors. Moreover, the existing resilient modulus and permanent deformation prediction models with stress and moisture dependence are feasible for MSWIBA as well. Additionally, heavy metal leaching concentrations obtained from column test can meet the standard of surface water quality class V in China. This work is expected to benefit the design work and provide the insight of performance of MSWIBA as road embankment material, and promote its further widespread application in road construction. [ABSTRACT FROM AUTHOR]

This paper provides an overview and brief evaluation of China's rural tourism. Beginning with the form of poverty alleviation through tourism, China's rural tourism has undergone over 20 years of development and exhibited some unique features in its development pattern, scale and business operational models in accordance with China's political, social and economic systems. Government plays a decisive role in developing rural tourism in China. However, rural tourism has been valued mainly as an economic means for rural development during the country's modernisation process. Overlooking rurality as an essential issue in rural tourism may lead development to a wrong direction, which could jeopardise the sustainability of the industry. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: As global aging intensifies, older adults with chronic diseases are of increasing concern. Home and community-based services (HCBSs) have been proven to promote self-rated health (SRH) in older adults, but no research explored the associations between the use of overall HCBSs, three different types of HCBSs (health care, daily care, and social support services) and SRH among older adults with chronic diseases. Consequently, this study applies a national publicly available database to examine these associations among older adults with chronic diseases., Methods: 8,623 older adults with chronic diseases (≥ 60 years old) were included in this study. SRH was evaluated applying a concise question with a 1 - 5 scale. HCBSs utilization was assessed through the question, "What kind of HCBSs were used in the community?". Univariate general linear regression models aimed to compare the mean values of SRH in terms of HCBSs utilization in each group. This study is a cross-sectional study design and the relationship between HCBSs utilization and SRH was assessed by multilevel linear regression., Results: The mean score for SRH among the respondents was 3.19, of whom 20.55% used one or more HCBSs, 19.47% utilized health care services, 2.44% utilized social support services, and only 0.55% utilized daily care services. The use of HCBSs was found to be linked to SRH among older adults with chronic diseases (β = 0.085, SE = 0.025, p < 0.001). SRH among older adults with chronic diseases was strongly linked to the use of health care and social support services (β = 0.068, SE = 0.025, p < 0.001; β = 0.239, SE = 0.063, p < 0.001, respectively). However, there was no significant association between the use of daily care services and SRH among older adults with chronic diseases., Conclusion: This study revealed that HCBSs utilization was positively and significantly linked to SRH in Chinese older adults with chronic diseases. Furthermore, this study supposes the low utilization of social support and daily care services may be due to a mismatch between supply and demand. The government should offer the targeted HCBSs for older adults with chronic diseases according to their unique features to enhance their health status., (© 2024. The Author(s).)

Porcine reproductive and respiratory syndrome virus (PRRSV) causes huge economic loss to the global swine industry. Even though several control strategies have been applied, PRRS is still not effectively controlled due to the continuous emergence of new variants and limited cross-protection by current vaccines. During the routine epidemiological investigation in 2017, two PRRSV variants were identified from a severe abortion farm and a clinically healthy farm, respectively. The viruses were isolated and denominated as XJ17-5 and JSTZ1712-12. Genomic sequencing indicated that their genomes are both 14,960 bp in length sharing 99.45% nucleotide identity. Sequence alignments identified a discontinuous 30-amino-acid deletion and a continuous 120-amino-acid deletion in nsp2 of both isolates. Genome-based phylogenetic analysis confirmed that XJ17-5 and JSTZ1712-12 belong to the HP-PRRSV subtype but form a new branch with other isolates containing the same 150-amino-acid deletion in nsp2 . Pathogenic analysis showed that XJ17-5 is highly virulent causing 60% mortality, while JSTZ1712-12 is avirulent for piglets. Furthermore, fragment comparisons identified 34-amino-acid differences between XJ17-5 and JSTZ1712-12 that might be associated with the distinct virulence. The identification of highly homologous HP-PRRSV variants with new genetic feature and distinct virulence contributes to further analyze the pathogenesis and evolution of PRRSV in the field.

A novel porcine reproductive and respiratory syndrome virus 2 (PRRSV2) was isolated from diseased piglets in Shandong, China in 2017 and denominated as SD17-38. ORF5 sequencing showed that SD17-38 contains a unique serine/asparagine deletion at position 33 and an asparagine insertion at position 60 of GP5, which has never been described. The SD17-38 complete genome was then determined, and genome-based phylogenetic analysis showed that SD17-38 is clustered with NADC30-like isolates. Sequence alignment and recombination analyses by RDP4 and SimPlot all indicated that SD17-38 is a recombinant virus from NADC30 (lineage 1), BJ-4 (lineage 5) and TJ (lineage 8) isolates. Animal challenge study in 4-week piglets showed that SD17-38 causes high fever (≥41°C), 100% morbidity and 40% mortality. In addition, significantly lower weight gain and severe histopathological lung lesions could be observed in SD17-38-infected pigs. In particular, the unique deletion and insertion in GP5 were stable during the challenge study. This study provides direct evidence for the natural occurrence of recombination events among three lineages of PRRSV2 in Chinese swine herds, resulting in the emergence of novel PRRSV variant with unique genetic property and high pathogenicity., (© 2018 Blackwell Verlag GmbH.)