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Accurate streamflow estimation remains a great challenge although diverse modeling techniques have been developed during recent decades. In contrast to the process based models, the empirical data driven methods are easy to operate, require low computing capacity and yield fairly accurate outcomes, among which the state space (STATE) approach takes use of the temporal structures inherent in streamflow series and serves as a feasible solution for streamflow estimation. Yet this method has rarely been applied, neither its comparison with other methods. The objective was to compare the performance of an autoregressive STATE approach to the traditional multiple linear regression and artificial neural network in simulating annual streamflow series of 15 catchments located in the Loess Plateau of China. Annual data of streamflow (Q), precipitation (P) and potential evapotranspiration (PET) during 1961 ~ 2013 were collected. The results show that STATE was generally the most accurate method for Q estimation, explaining almost 90% of the total variance averaged over all the 15 catchments. The estimation of streamflow relied on its own of the previous year for most catchments. Besides, the impacts of P and PET on the temporal distribution of streamflow were almost equal. Missing data were estimated using the STATE method, which allowed inter annual trend analysis of the streamflow. Significant downward trends were manifested at all the 15 catchments during the study period and the corresponding slopes ranged from 0.24 to 1.71 mm/y. These findings hold important implications for hydrological modelling and management in China's Loess Plateau and other arid and semi-arid regions [ABSTRACT FROM AUTHOR]

Abstract: Phlebotomine sandflies (Diptera: Phlebotomidae) are vectors of the zoonotic disease leishmaniasis. To better understand the distribution of phlebotomine sandflies in order to facilitate control of leishmaniasis transmission, the present study explored the impacts of climate and landscape on local abundances of Phlebotomus chinensis in northwestern mainland China. Identification records were used to create a geodatabase for the locations at which P. chinensis had been collected in the region, and a regional‐scale map was developed to show the distribution of P. chinensis. Location data and data on environmental factors during the years in which the samples were collected were incorporated, and a presence‐only modelling method was used to evaluate the species' habitat preferences and to predict its potential distribution in northwestern mainland China. Jackknife analysis revealed that several meteorological variables, including maximum temperature in the warmest quarter, precipitation in the driest month, daily average temperature and daily precipitation, significantly affected the presence of this species. Moreover, the presence of P. chinensis was significantly associated with grassland and shrubland. Probability distributions using maximum entropy were used to map the distribution ranges of P. chinensis based on suitable habitats in northwestern mainland China. The models generated can be used to develop detailed strategies for the prevention and control of leishmaniasis. [ABSTRACT FROM AUTHOR]

Background: Tea is the world’s most popular non-alcoholic beverage. China and India are known to be the largest tea producing countries and recognized as the centers for the domestication of the tea plant (Camellia sinensis (L.) O. Kuntze). However, molecular studies on the origin, domestication and relationships of the main teas, China type, Assam type and Cambod type are lacking. Methodology/Principal Findings: Twenty-three nuclear microsatellite markers were used to investigate the genetic diversity, relatedness, and domestication history of cultivated tea in both China and India. Based on a total of 392 samples, high levels of genetic diversity were observed for all tea types in both countries. The cultivars clustered into three distinct genetic groups (i.e. China tea, Chinese Assam tea and Indian Assam tea) based on STRUCTURE, PCoA and UPGMA analyses with significant pairwise genetic differentiation, corresponding well with their geographical distribution. A high proportion (30%) of the studied tea samples were shown to possess genetic admixtures of different tea types suggesting a hybrid origin for these samples, including the Cambod type. Conclusions: We demonstrate that Chinese Assam tea is a distinct genetic lineage from Indian Assam tea, and that China tea sampled from India was likely introduced from China directly. Our results further indicate that China type tea, Chinese Assam type tea and Indian Assam type tea are likely the result of three independent domestication events from three separate regions across China and India. Our findings have important implications for the conservation of genetic stocks, as well as future breeding programs. [ABSTRACT FROM AUTHOR]

We aimed to evaluate velopharyngeal function and speech outcomes of Sommerlad palatoplasty combined with sphincter pharyngoplasty in surgical repair of cleft palate in patients over five years old. Fifty-eight patients were reviewed between the years 2013 and 2017, 31 of whom were treated with Sommerlad palatoplasty combined with sphincter pharyngoplasty, (mean age 15 (range 9 - 22) years), and 27 were treated with Sommerlad palatoplasty alone (mean age 18 (range 10-25) years). Velopharyngeal function was evaluated by radiographic lateral cephalometry and nasoendoscopy. Hypernasality, nasal emissions, and intelligibility were used to assess speech. The rate of velopharyngeal competence was 20/31 in the palatoplasty plus pharyngoplasty group and 7/27 in the palatoplasty alone group after surgical treatment (p=0.003). The improvements in hypernasality (p=0.024), air emission (p=0.004), and speech intelligibility (p=0.004) in the palatoplasty plus pharyngoplasty group was better than that in the palatoplasty alone group. It has been suggested that the surgical approach with the palatoplasty together with the sphincter pharyngoplasty has a higher rate of success in surgical repair of older patients with cleft palate., (Copyright © 2020 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Objective: To compare risk factors and bacterial etiology in patients with early-onset versus late-onset ventilator-associated pneumonia (VAP) in intensive care unit (ICU). Methods: This prospective cohort study enrolled mechanically ventilated patients hospitalized for more than 48 hours in the first affiliated hospital, China Medical University from Jan 2012 to Jun 2016. Subjects were classified by ventilator status: early-onset VAP (< 5 d ventilation, E-VAP) or late-onset VAP (≥ 5 d ventilation, L-VAP). Potential risk factors and pathogen were evaluated. Results: A total of 4 179 patients in adult ICU were screened, 3 989 (95.5%) of whom were mechanically ventilated, 962 patients with mechanical ventilation time ≥ 48 h. VAP developed in 142 patients. E-VAP and L-VAP had different potential risk factors based on statistical analysis.Independent risk factors for E-VAP included male ( OR =1.825, 95% CI 1.006-3.310), chronic obstructive pulmonary disease (COPD; OR =3.746, 95% CI 1.795-7.818), emergency intubation ( OR =1.932, 95% CI 1.139-3.276), aspiration ( OR =3.324, 95% CI 1.359-8.130). Whereas independent risk factors for L-VAP were coma ( OR =2.335, 95% CI 1.300-4.194), renal dysfunction ( OR =0.524, 95% CI 0.290-0.947), emergency intubation ( OR =2.184, 95% CI 1.334-3.574). Mortality in E-VAP and L-VAP group were both higher than the non-VAP group[30.2%(19/63)vs 19.8%(162/820), P =0.044; 29.1%(23/79) vs 19.8%(162/820), P =0.046]. The pathogens isolated from early-onset versus late-onset VAP were not significantly different between groups, which the most common ones were acinetobacter baumannii, pseudomonas aeruginosa and klebsiella pneumoniae. Conclusion: E-VAP and L-VAP have different risk factors, however related pathogens are similar. Different specific preventive strategies are suggested based on different onset of VAP.

Objective: To understand the prevalence of senile dementia in the elderly aged ≥60 years in China between 2000 and 2015. Methods: Publications between 2000 and 2015 were retrieved from China National Knowledge Infrastructure (CNKI), Wanfang Databases, Chinese Science and Technology Journal Databases (VIP) and PubMed. Observational studies on prevalence of senile dementia were included. Meta-analysis was carried out by using R software. Results: A total of 25 papers were included in this study. The total number of participants investigated was 76 980, with 4 295 dementia cases identified. The prevalence of senile dementia in the elderly was 5.15% (95% CI : 4.21%-6.09%); Subgroup analysis showed that the women had a higher prevalence (6.08%) than the men (4.10%); and the prevalence was significant increased with age (The senile dementia prevalence was 1.01% in age groups 60-64 years, but 23.60% in age group ≥85 years). The prevalence of Alzheimer's disease (3.56%) was higher than that of cerebral vascular dementia (1.11%). The senile dementia prevalence in the illiterate was 8.74%, higher than 3.17% in the literate. The prevalence of senile dementia in the unmarried was 6.83%, higher than that in the married (3.95%). Conclusion: The prevalence of senile dementia was high in the population aged ≥60 years in China. Age, sex, education level and marital status might influence the prevalence of senile dementia.

Aims: Hereditary non-polyposis colorectal cancer, thyroid medullary carcinoma, breast/ovarian cancer and gastric cancer/breast cancer syndrome are encountered in surgery. Some gastric cancer/breast cancer syndrome may be the result of a CDH1 germline mutation. This is the first report of CDH1 germline mutations gastric cancer/breast cancer syndrome in Chinese patients., Methods: Peripheral blood from the proband, as well as, her first and second degree relatives was collected and CDH1 gene exon 1-16 mutations were screened. E-cadherin/beta-catenin proteins expression and histopathologic features were examined on gastric cancer/breast cancer tissues from the proband., Results: A C-->T nucleotide substitution at exon 13 (mRNA 2200 locus, Accession number NM-004360) was found. This was a transition from GCC-->GCT in DNA sequence (Ala154Ala). Diffuse-type gastric cancer and infiltrating ductal breast carcinoma were present. Both tumours preserved E-cadherin/beta-catenin expression immunohistochemically., Conclusions: Familial cancer syndrome with diffuse-type gastric cancer/breast cancer proband in Chinese has a propensity of early onset during lifespan. No truncating or splice-site CDH1 mutations had been identified in this family. A silent nucleotide variation in exon 13 of the CDH1 gene may contribute to some forms of cancer susceptibility.

The phenotype and haplotype frequencies of human leukocyte antigens (HLA)-DR and -DQ in 32 Chinese patients with the mucocutaneous (MC) type of Behçet's disease (BD) were calculated and compared with those in 310 healthy control Chinese and with those in 80 Chinese patients with recurrent aphthous stomatitis (RAS). We found that the phenotype frequency of HLA-DRw8 [corrected P (Pc)<0.005] and the haplotype frequencies of HLA-DRw8/DQw1 (Pc<0.005), -DRw8/DQw5(w1) (Pc<0.0005), -DRw12(5)/DQw1 (Pc<0.005), -DRw12(5)/DQw6(w1) (Pc< 0.0005), and -DRw52/DQw1 (Pc<0.005) in patients with the MC type of BD were significantly greater than those in healthy control subjects. This finding suggests that individual Chinese with HLA-DRw8 antigen and HLA-DRw8/DQw1, -DRw8/DQw5(w1), -DRw12(5)/DQw1, -DRw12(5)/DQw6(w1) and -DRw52/DQw1 haplotypes are more likely to have the MC type of BD. Furthermore, the relative risks (RRs) of HLA-DRw8/DQw1 (5.6), -DRw8/ DQw5 (w1) (10.0), and -DRw12(5)/DQw6(w1) (14.4) haplotypes in patients with the MC type of BD were equal to or higher than the RR of HLA-DRw8 phenotype (5.6), suggesting that some of the HLA-DR/DQ haplotypes may play more important roles than the individual HLA-DR and -DQ phenotypes for the development of the MC type of BD. The phenotype frequencies of HLA-DR5 (Pc<0.01), -DRw8 (Pc<0.005) and -DQw1 (Pc<0.05) as well as the haplotype frequencies of HLA-DR5/DQw1 (P<0.005) and -DRw8/DQw1 (Pc<0.00005) in patients with the MC type of BD were significantly higher than those in patients with RAS. Moreover, the RRs of HLA-DR5/DQw1 (29.1) and -DRw8/DQw1 (47.4) haplotypes were greater than the RRs of HLA-DR5 (10.4), -DRw8 (23.4) and -DQw1 (4.0) antigens. These results suggest that some specific HLA-DR/DQ haplotypes may be more important than the individual HLA-DR and -DQ phenotypes in the disease shift from RAS to the MC type of BD.

One hundred and seventy-two strains of Escherichia coli isolated from diarrheal patients in Beijing, P.R. China, were analyzed for plasmid DNA profile, HEp-2 cell adherence ability and reactivity to 10 previously described DNA probes. They had not been recognized as pathogenic E. coli in China. Of the 110 strains tested, 76 (69%) contained one or multiple large plasmids. Of the 71 strains with the large plasmids 64 could adhere to HEp-2 cells. Of the 172 strains, 102 (59.3%) were hybridized with at least one of the 10 probes. Of those, seven strains hybridized with enteroaggregative E. coli (EAggEC) probe. Their serotypes were O128 (two strains), O6 (one strain), and O111 (one strain). Three strains were untypable. Six and three strains were hybridized with enteropathogenic E. coli (EPEC) attaching and effacing genes (eae) or EPEC adherence factor (EAF) probe, respectively. Two non-O157: H7 strains hybridized with enterohemorrhagic E. coli (EHEC) probe. Seventy-two strains (41.9%) hybridized with shiga-like toxin 2 or 1 (SLT2 or SLT1) probes. Among the SLT1 or SLT2 probe-positive strains, 54 hybridized with invasive (INV) plasmid probe developed for identification of enteroinvasive E. coli (EIEC) and Shigella species. The INV and SLT probe-positive strains might represent a new variety of verotoxin-producing E. coli (VTEC).

The inhabitants with positive eggs of whipworm and ascaris in a village of Jiangdou County were examined and treated with different antihelmintic drugs twice a year. The uncured population were treated by drug administration once again. On an average the efficiency of drug treatment (cure rate x treatment rate) was 56.7% in whipworm and 64.5% in ascaris. The program had been carried out for five years. The positive rate of eggs of whipworm and ascaris in the population decreased from 64.7% and 52.1% to 2.7% and 4.1%, respectively, the mean increase in infection rates among population at 5 or 7 months after treatment was 2.68 (0.86-5.74)% and 6.94(1.72-17.27)%, respectively.