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The direct ingestion of indoor dust particles at historical heritage sites is a primary exposure pathway for employees to heavy metals. Water-soluble ions (WSIs) and heavy metal levels, sources, bioaccessibility, and health risks associated with indoor dust in the Mogao Grottoes were analyzed using comprehensive methods to determine the differences in the concentrations and distribution characteristics of WSIs and heavy metals between statue dust and floor dust. The concentrations of WSIs and heavy metals and the magnetic values of χ lf and SIRM in indoor dust were higher than those in street dust and topsoil. The mean χ lf and SIRM of statue dust particles were 100.3 × 10 − 8 m 3 k g − 1 and 1686.9 × 1 0 − 5 Am 2 k g − 1 . Specifically, the concentration of Pb was 277 mg k g − 1 , 15-fold higher than the background value, indicating the continual receipt of heavy metals with high magnetic minerals during dust deposition. WSIs mainly originate from the weathering of surrounding rocks and earthen plaster; Pb originates from the shedding of paint of murals and sculptures; and Zn, Cu, and magnetic minerals originate from traffic sources. The bioaccessibility of heavy metals is high in the gastrointestinal phases of indoor dust. Overall, the health risks posed by heavy metals in indoor dust were low, with moderate to high risks in individual caves. Ingestion presents the highest noncarcinogenic and carcinogenic risk to employees. These results provide essential knowledge on indoor dust characteristics in the Mogao Grottoes, facilitating strategies for dust pollution mitigation and employee health risk control. [ABSTRACT FROM AUTHOR]

Miscanthus lutarioriparius is a species of bioenergy crop unique to China. It is widely distributed in the south of China with high resistance to drought and salt stress. To date, the molecular mechanism of the adaption to drought stress in M. lutarioriparius is little known. In this study, RNA-seq technology was employed to analyze the transcriptome changes of diploid and tetraploid M. lutarioriparius after drought treatment. It was found that the number of differentially expressed genes in diploid M. lutarioriparius was much higher than tetraploid, whereas the tetraploid M. lutarioriparius may require fewer transcriptional changes. While the transcriptional changes in drought-tolerant tetraploid M. lutarioriparius are less than that of diploid, more known drought-tolerant pathways were significantly enriched than drought-sensitive diploid M. lutarioriparius. In addition, many drought-tolerance-related genes were constitutively and highly expressed in tetraploid under either normal condition or drought stress. These results together demonstrated that drought-tolerant tetraploid M. lutarioriparius, on the one hand, may preadapt to drought by constitutively overexpressing a series of drought-tolerant genes and, on the other hand, may adapt to drought by actively inducing other drought-tolerant-related pathways. Overall, this study could deepen our understanding of the molecular mechanism of drought-tolerance in bioenergy plants. [ABSTRACT FROM AUTHOR]

Precambrian microcontinents represent key tectonic units in the accretionary collages of the eastern Central Asian Orogenic Belt (ECAOB), and possess a wealth of information about the geological evolution. Here, we describe newly discovered late Neoarchean amphibolite of the Huangsong Group collected from drillhole ZK4301 at the Sishanlinchang gold mining area in the Jiamusi–Khanka Block. LA–ICP–MS U–Pb dating for zircons from the amphibolite yields a weighted‐mean 207Pb/206Pb age of 2539 ± 4 Ma, which can be referred to as its protolithic age. Zircons in the 2.54‐Ga amphibolite show high and positive εHf(t) values ranging from +4.2 to +6.8 and single‐stage Hf model ages (TDM1) of 2.60 to 2.68 Ga, suggesting that a depleted mantle source might have been metasomatized by fluids/melts from subducted crustal materials. The amphibolite displays low SiO2 and alkalis, and high TFe2O3 and Mg# (0.50–0.52), and is classified as a subalkaline series, medium‐ to high‐K calc‐alkaline basaltic rock. Our geochemical and geochronological data reveal that a late Archean tectono‐magmatic event is preserved in the Jiamusi–Khanka Block, providing robust evidence for the existence of an Early Precambrian basement. The 2.54‐Ga basaltic magmatism likely took place in an active continental margin/island arc setting. [ABSTRACT FROM AUTHOR]

China has become one of the most prominent areas of global land cover change during the past few decades. These changes can directly influence meteorological parameters thus further regulating tropospheric ozone (O 3) formation. Moreover, changes in biogenic emissions due to land cover variation can also have an indirect effect on O 3 concentration. This study applied the Community Multiscale Air Quality model to comprehensively evaluate the impacts of significant land cover change on O 3 levels in China during summertime between 2001 and 2019. The results showed that the daily maximum 8–h average O 3 concentration (MDA8 O 3) increased by 3.6–8.9 μg/m3, 2.8–8.0 μg/m3, 3.8–9.6 μg/m3, -1.5–6.2 μg/m3, and -0.6–2.5 μg/m3 in Beijing–Tianjin–Hebei region, Yangtze River Delta, Pearl River Delta, Sichuan Basin, and Fenwei Plain, respectively, in response to land cover variation. The research identified that the direct effect was the primary factor in raising O 3 levels which mainly altered O 3 concentration by changing vertical import and dry deposition velocity. Moreover, land cover variation tended to decrease biogenic nitric oxide emission and increase biogenic volatile organic compounds emission on the whole, and cause an obvious increase of MDA8 O 3 by 1.8–4.9 μg/m3 in Pearl River Delta due to the indirect effect. This study offered valuable insights into the impacts of land cover change on O 3 levels, highlighting the need for policymakers to consider land cover variation on air pollutants concentration for devising comprehensive multi-pollutant control strategies. [Display omitted] • China has experienced significant land cover change during the past few decades. • Direct effect of land cover variation dominated the changes in O 3 concentration. • Indirect effect of land cover variation largely increased the O 3 level in PRD. • Changes in vertical diffusion and dry deposition mainly drove the O 3 variation. [ABSTRACT FROM AUTHOR]

The distributions of bird species have changed over the past 50 years in China. To evaluate whether the changes can be attributed to the changing climate, we analyzed the distributions of 20 subspecies of resident birds in relation to climate change. Long-term records of bird distributions, gray relational analysis, fuzzy-set classification techniques, and attribution methods were used. Among the 20 subspecies of resident birds, the northern limits of over half of the subspecies have shifted northward since the 1960s, and most changes have been related to the thermal index. Driven by climate change over the past 50 years, the suitable range and latitude or longitude of the distribution centers of certain birds have exhibited increased fluctuations. The northern boundaries of over half of the subspecies have shifted northward compared with those in the 1960s. The consistency between the observed and predicted changes in the range limits was quite high for some subspecies. The changes in the northern boundaries or the latitudes of the centers of distribution of nearly half of the subspecies can be attributed to climate change. The results suggest that climate change has affected the distributions of particular birds. The method used to attribute changes in bird distributions to climate change may also be effective for other animals. [ABSTRACT FROM AUTHOR]

Changshaling Structural Belt is an important oil and gas exploration area in Jiudong Basin, and abnormal high pressure is universal in the zone. The paper proposes a new three-dimensional (3D)pore pressure calculation method based on single point hypothesis, which can use 3D interval velocity data to estimate 3D pore pressure. The novel method was applied to the 3D pore pressure calculation and analysis of Changshaling Structural Belt. Firstly, the pore pressure profile and model parameters of several key exploratory wells were established. Secondly, the 3D interval velocity data of the structural belt was obtained by seismic inversion. Further, the computer program was developed, and it was used to calculate the 3D pore pressure of Changshaling Structural Belt. Finally, with the 3D pressure results of Changshaling Structural Belt, the pore pressure distribution of this zone was systematically analyzed, with positive results. [ABSTRACT FROM AUTHOR]

Human natural killer (NK) cells are essential for controlling infection, cancer, and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B, and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B, and -C genes, we show that the Chinese Southern Han (CHS) are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the CHS KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C-specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B-specific receptors. In all these characteristics, the CHS represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity, and effector strength, likely augmenting resistance to endemic viral infections., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

We profiled the serological responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid (N) protein and spike (S) glycoprotein. The majority of the patients developed robust antibody responses between 17 and 23 days after illness onset. Delayed, but stronger, antibody responses were observed in critical patients., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objective: To study the polymorphisms of the KIR2DL4 gene in a southern Han Chinese population., Methods: Genomic DNA isolated from 306 unrelated individuals was amplified by using KIR2DL4-specific PCR primers. The PCR products were genotyped for the entire coding sequence by sequencing-based typing (SBT). Assignment of allelic profile was accomplished with an Assign 3.5 software. For samples with inconclusive SBT results, the RT-PCR products covering the entire coding sequence of the KIR2DL4 gene were subjected to cloning and haplotype sequencing., Results: Among the 306 individuals, 11 alleles were detected, of which 5 novel alleles were officially named by the KIR subcommittee of the World Health Organization Nomenclature Committee for factors of HLA system. The observed frequencies for the 11 alleles were KIR2DL4 *00102 (75.5%), *00103 (8.2%), *00501 (34.0%), *00503 (0.7%), *00504 (0.7%), *00602 (14.4%), *00801 (11.4%), *011 (22.2%), *032 (0.3%), *033 (0.3%) and *034 (0.3%). The ratio of 10A type alleles including 2DL4*00102, *00103, *00501, *00503, *00504, *00602, *032, *033, *034 and 9A type alleles including 2DL4*00801, *011 were 97.0% and 33.0%, respectively, with a ratio of 2.9:1., Conclusion: The allelic diversity of the KIR2DL4 gene in southern Han Chinese has been elucidated, which may provide valuable data for research on transplantation, reproductive immunity, KIR-associated disease and evolution.

Objective: To study genetic polymorphisms of the KIR2DS4 gene among ethnic Hans from southern China., Methods: Genomic DNA was isolated from 306 unrelated individuals and amplified with KIR2DS4-specific PCR primers. KIR2DS4-positive samples were genotyped for the entire coding sequence by sequencing-based typing (SBT). Assignment of allelic genotypes was accomplished by using Assign 3.5 software. For samples with inconclusive SBT results, RT-PCR products covering the entire coding sequence of the KIR2DS4 gene were subjected to cloning and haplotype sequencing., Results: Among all tested samples, 297 were demonstrated to have carried the KIR2DS4 framework gene. For KIR2DS4-positive samples subjected to SBT for the entire coding sequences, no background was observed with the obtained sequences. Three of the seven identified alleles were of novel types, which were officially named by the KIR subcommittee of the World Health Organization Nomenclature Committee for Factors of HLA System. The observed frequencies for the 7 alleles were KIR2DS4*00101 (78.8%), *003 (10.5%), *004 (16.0%), *010 (23.2%), *017 (0.3%), *00105 (0.3%) and *018 (0.7%), respectively. Allele KIR2DS4*007 was not found. The overall frequency for normal cell-surface expression KIR2DS4 alleles including 2DS4*00101, *017 and *00105 was 79.4%, and that for non cell-surface expression alleles including 2DS4*003, *004, *010 and *018 was 50.4%. The ratio between the two was 1.6:1., Conclusion: The present study has elucidated the allelic diversity of KIR2DS4 among ethnic Hans from southern China, which may provide valuable data for transplantation as well as studies on KIR-associated disease and evolution.

Objective: To categorize ambiguous allelic combinations encountered in genotyping of functional KIR genes by sequencing-based typing of the entire coding sequence and develop an efficient approach to identify such ambiguities., Methods: Fourteen KIR functional framework genes from 306 ethnic Chinese individuals were genotyped for the entire encoding sequence. The number of ambiguities was directly counted. Based on the differences within each ambiguous allelic combination, group-specific PCR primers and sequencing primers for amplifying the target allelic sequence were designed. The PCR products were then subjected to sequencing in order to identify the ambiguities., Results: The 14 functional KIR genes were subjected to sequencing-based typing (SBT) for the entire encoding sequence. Six ambiguous allelic combinations were identified. The most common ambiguity 3DL2*(002, 007/010, 015) has accounted for 12.09% of the 306 tested samples. The remaining 5 ambiguities were (2DL5A*001, 2DL5B*006/2DL5A*012, 2DL5B*008), 3DL3*(001, 010/009, 048), 3DL2*(007, 008/016, 027), 3DL3*(00801, 048/01001, 026) and 3DL3*(00802, 048/01002, 026) have accounted for 5.88% (18/306), 3.59% (11/306), 2.29% (7/306), 1.31% (4/306) and 1.31% (4/306) of all samples, respectively. For two ambiguities (2DL5A*001, 2DL5B*006/2DL5A*012, 2DL5B*008) and 3DL2*(007, 008/016, 027) subjected to group-specific PCR and re-sequencing, only one demonstrable genotype was identified, While for in each of other four ambiguities subjected to group-specific PCR and re-sequencing, two different genotypes were identified., Conclusion: An efficient approach by group-specific PCR and sequencing retest has been established to clarify the ambiguities during SBT testing for functional KIR framework genes, which may have a broad application in KIR sequencing-based typing.

Background: Sleep deprivation is common in critically ill patients in intensive care units (ICU). It can result in delirium, difficulty weaning, repeated nosocomial infections, prolonged ICU length of stay and increased ICU mortality. Melatonin, a physiological sleep regulator, is well known to benefit sleep quality in certain people, but evidence for the effectiveness in ICU sleep disturbance is limited., Methods/design: This study has a prospective, randomized, double-blind, controlled, parallel-group design. Eligible patients are randomly assigned to one of the two treatment study groups, labelled the 'melatonin group' or the 'placebo group'. A dose of 3 mg of oral melatonin or placebo is administered at 9:00 pm on four consecutive days. Earplugs and eye masks are made available to every participant. We plan to enrol 198 patients. The primary outcome is the objective sleep quality measured by the 24-hour polysomnography. The secondary outcomes are the subjective sleep quality assessed by the Richards Campbell Sleep Questionnaire, the anxiety level evaluated by the Visual Analogue Scale-Anxiety, the number of delirium-free days in 8 and 28 days, the number of ventilation-free days in 28 days, the number of antibiotic-free days, ICU length of stay, the overall ICU mortality in 28 days and the incidence and severity of the side effects of melatonin in ICU patients. Additionally, the body stress levels, oxidative stress levels and inflammation levels are obtained via measuring the plasma melatonin, cortisone, norepinephrine, malonaldehyde(MDA), superoxide dismutase(SOD), interleukin-6 (IL-6) and interleukin-8 (IL-8)concentrations., Discussion: The proposed study will be the first randomized controlled study to use the polysomnography, which is the gold standard of assessing sleep quality, to evaluate the effect of melatonin on the sleep quality and circadian rhythms of ICU patients. The results may recommend a new treatment for ICU patients with sleep deprivation that is safe, effective and easily implementable in daily practice., Trial Registration: This study was registered with ClinicalTrials (NCT; registration number: ChiCTR-TRC-14004319) on 4 March 2013.