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A local long-lived convective system developed at midnight over inland South China, producing record-breaking rainfall in Guangzhou on 7 May 2017. This study examines the physical processes responsible for nocturnal convection initiation (CI) and growth. Observational analyses show that the CI occurs in the warm sector under weakly forced synoptic conditions at 500 hPa, while moderate but nocturnally enhanced low-level southeasterlies with a mesoscale moist tongue at 925 hPa intrude inland from the northern South China Sea. Convection-permitting model results show that mesoscale low-level convergence and increased moisture at the leading edge of the southeasterlies are favorable for CI dynamically and thermodynamically. Local ascent and potential instability are further enhanced by orographic lifting and warm moist air from the urban surface, respectively, which trigger convection in northern Guangzhou. The mesoscale moist tongue of southeasterly flows then meets convectively generated outflows, thereby maintaining strong updrafts and continuously triggering back-building convective cells in eastern Guangzhou. Sensitivity tests are conducted to estimate the relative roles of ambient southeasterly moist tongue and urban thermal effects. The southeasterly moist tongue provides moisture that is crucial for CI, while warm moist air from the urban surface is lifted at the leading edge of the southeasterlies and locally facilitates convection. Therefore, the mesoscale processes of lifting and moistening due to nocturnal southeasterlies and their strong interaction with the local factors (orographic lifting, urban heating, and cold-pool-related ascent) provide the sustained lifting and instability crucial for triggering the local long-lived convective systems. The multiscale processes shed light on the understanding of the nocturnal warm-sector heavy rainfall inland. [ABSTRACT FROM AUTHOR]

This study examines the diversity of low-level jet (LLJ) formation and related physical processes over southern China. A total of 171 LLJ formation events with enhanced daily southwesterlies and early-morning maximum wind speeds were observed during the mei-yu seasons of 1989–2018. The LLJs can be further categorized into four types based on the increases in the daily mean and diurnal amplitude of the low-level winds. Analysis of the synoptic-scale disturbances shows that the two types of LLJ formation (Q1 and Q4), which feature large increases of daily southerly wind components, are mainly induced by west-east dipole patterns of pressure change, in association with the enhanced southwest vortex and/or the western Pacific subtropical high (WPSH). In contrast, the other two types (Q2 and Q3), which feature relatively large increases in their daily westerly components, are related to a northwest-southeast dipole pattern of pressure change due to the mid-latitude trough and the WPSH. We further analyze the considerable variations in the diurnal thermal forcing among the LLJ formation events. The strong (weak) daytime heating of solar radiation leads to relatively large (small) increases in the diurnal amplitude of low-level winds in Q1 and Q2 (Q3 and Q4) types. Therefore, different combinations of synoptic-scale disturbances and diurnal thermal forcings are found to account for the diversity in LLJ formation and associated differences in downstream rainfall patterns. These results help to improve our understanding and prediction of the formation of LLJs. [ABSTRACT FROM AUTHOR]

Study Question: Can whole genome sequencing (WGS) offer a relatively cost-effective approach for embryonic genome-wide haplotyping and preimplantation genetic testing (PGT) for monogenic disorders (PGT-M), aneuploidy (PGT-A) and structural rearrangements (PGT-SR)?Summary Answer: Reliable genome-wide haplotyping, PGT-M, PGT-A and PGT-SR could be performed by WGS with 10× depth of parental and 4× depth of embryonic sequencing data.What Is Known Already: Reduced representation genome sequencing with a genome-wide next-generation sequencing haplarithmisis-based solution has been verified as a generic approach for automated haplotyping and comprehensive PGT. Several low-depth massively parallel sequencing (MPS)-based methods for haplotyping and comprehensive PGT have been developed. However, an additional family member, such as a sibling, or a proband, is required for PGT-M haplotyping using low-depth MPS methods.Study Design, Size, Duration: In this study, 10 families that had undergone traditional IVF-PGT and 53 embryos, including 13 embryos from two PGT-SR families and 40 embryos from eight PGT-M families, were included to evaluate a WGS-based method. There were 24 blastomeres and 29 blastocysts in total. All embryos were used for PGT-A. Karyomapping validated the WGS results. Clinical outcomes of the 10 families were evaluated.Participants/materials, Setting, Methods: A blastomere or a few trophectoderm cells from the blastocyst were biopsied, and multiple displacement amplification (MDA) was performed. MDA DNA and bulk DNA of family members were used for library construction. Libraries were sequenced, and data analysis, including haplotype inheritance deduction for PGT-M and PGT-SR and read-count analysis for PGT-A, was performed using an in-house pipeline. Haplotyping with a proband and parent-only haplotyping without additional family members were performed to assess the WGS methodology. Concordance analysis between the WGS results and traditional PGT methods was performed.Main Results and the Role Of Chance: For the 40 PGT-M and 53 PGT-A embryos, 100% concordance between the WGS and single-nucleotide polymorphism (SNP)-array results was observed, regardless of whether additional family members or a proband was included for PGT-M haplotyping. For the 13 embryos from the two PGT-SR families, the embryonic balanced translocation was detected and 100% concordance between WGS and MicroSeq with PCR-seq was demonstrated.Limitations, Reasons For Caution: The number of samples in this study was limited. In some cases, the reference embryo for PGT-M or PGT-SR parent-only haplotyping was not available owing to failed direct genotyping.Wider Implications Of the Findings: WGS-based PGT-A, PGT-M and PGT-SR offered a comprehensive PGT approach for haplotyping without the requirement for additional family members. It provided an improved complementary method to PGT methodologies, such as low-depth MPS- and SNP array-based methods.Study Funding/competing Interest(s): This research was supported by the research grant from the National Key R&D Program of China (2018YFC0910201 and 2018YFC1004900), the Guangdong province science and technology project of China (2019B020226001), the Shenzhen Birth Defect Screening Project Lab (JZF No. [2016] 750) and the Shenzhen Municipal Government of China (JCYJ20170412152854656). This work was also supported by the National Natural Science Foundation of China (81771638, 81901495 and 81971344), the National Key R&D Program of China (2018YFC1004901 and 2016YFC0905103), the Shanghai Sailing Program (18YF1424800), the Shanghai Municipal Commission of Science and Technology Program (15411964000) and the Shanghai 'Rising Stars of Medical Talent' Youth Development Program Clinical Laboratory Practitioners Program (201972). The authors declare no competing interests.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Buses represent the main mode for intercity passenger transportation in China. In recent years, a multichannel ticketing strategy has been widely employed in the bus passenger transportation industry. However, the mechanisms and key drivers of the channels through which bus passengers purchase tickets are underexplored. Thus, the aim of this study is to empirically apply an integrated choice and latent variable (ICLV) approach to analyze ticketing channel choice behavior and the heterogeneous preferences of bus passengers. The variables incorporated in the model include the socioeconomic characteristics of passengers, trip attributes, and latent attitudes with 12 ordinal indicators. Based on the data of 1800 participants collected from the city of Beijing, China, this study develops a ticketing channel choice ICLV model merging a discrete choice model with a structural equation model. The key factors that affect the channel preference are further discussed through a comparison with a conventional multinomial logit (MNL) model. The results reveal that the three attitudinal variables have a significant influence on ticketing channel choice. Furthermore, this study indicates that perceptual differences exist due to various socioeconomic and trip characteristics. Personal privacy is a major obstacle that prevents passengers from choosing online channels, especially for older passengers and those with lower education. [ABSTRACT FROM AUTHOR]

In vegetable production, Chinese cabbage can readily accumulate cadmium (Cd) into its edible parts and exceed food safety standards. However, there are still some ecotypes that respond differently to cadmium stress. This study aimed to investigate the differences of Cd-induced (0, 10, 50, 100, 200 µM) response under hydroponic culture between two Chinese cabbage ecotypes which were promoted in northeastern China from the characteristics of biomass, uptake kinetic, accumulation, and initial oxidative stress. In this paper, it was confirmed that Jinfeng (JF) was a Cd-tolerant cultivar and had low Cd accumulation in edible part, while Qiutian (QT) was Cd-sensitive, exhibiting a faster Cd uptake rate but lacking effective Cd detoxication mechanisms, and was severely damaged by 10 µM Cd treatment. Conversely, even at a high Cd concentration of 200 µM, Jinfeng had weaker biomass inhibition, lower root Cd affinity, more difficult root-to-leaf translocation, and stronger antioxidant enzyme activity than Qiutian. In conclusion, Jinfeng can endure mild Cd stress (<10 µM), and Qiutian can be used as a Cd indicator. This study provides reliable materials and related data support for vegetable production in areas with mild Cd pollution. Novelty statement: This work further investigates the unique features of low-Cd accumulator in Chinese cabbage (Brassica pekinensis L.) seedlings as an interesting material for vegetable production in areas with mild Cd pollution. It also explains the differences between Cd-tolerant and Cd-sensitive cultivars under different cadmium stress levels and how these differences can alter their response. With the increase of Cd concentration, Cd-tolerant cultivars compared to Cd-sensitive cultivars showed less biomass decrease, lower accumulation, lower TF, more chemically stable Cd in roots and more active antioxidant enzymes under the same Cd stress level. With the development of seedlings, the uptake of Cd in roots and the translocation to the leaves were effectively restricted by the poor Cd affinity of roots, the conversion of Cd chemical forms and the promotion of antioxidase activities, in a Cd-tolerant low accumulator, Jinfeng. [ABSTRACT FROM AUTHOR]

Aim To report a study of the psychometric properties of the Chinese version of the Daily Record of Severity of Problems form. Background In China, the prevalence of premenstrual syndrome is not confirmed due to lack of prospective daily tools. Daily Record of Severity of Problems was a validated daily symptom chart widely used for the diagnosis of premenstrual syndrome. There is no such an instrument for Chinese women. Methods The convenience sample included 126 female students in a school of nursing from September 2010-March 2011 in China. All of them completed daily ratings for two menstrual cycles, Premenstrual Tension Syndrome Self-Rating scale and Zung Self-Rating Depression scale at the first day of menses in two cycles. Results The internal consistency coefficients of reliability for total score and the correlations of each item with the total score in two cycles were all high. The majority of the cycle to cycle test-retest reliability for total scores and the individual items for the two phases of the cycle were high. Factor analysis yielded four factors describing mood, behaviour, pain, and physical symptoms. There were moderate correlations of the total Daily Record of Severity of Problems during the late-luteal phase of both cycles with Premenstrual Tension Syndrome Self-Rating scale and Zung Self-Rating Depression scale. Conclusions The Daily Record of Severity of Problems Chinese version provides reliable and valid measures of premenstrual symptoms in Chinese women. It has satisfactory psychometric properties and is suitable for nursing implication. [ABSTRACT FROM AUTHOR]