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The source region of the Yellow River, located in the northeastern part of the Qinghai-Tibetan Plateau, is the typical environmentally fragile region of Chinese eco-environment. As the important water source supplying area of Yellow River, the source region is known as “plateau’s water tower”. There inhabit large quantities of rare wild animals. In this study, based on land ecological classification and field investigation, we used landsat images obtained in 2000 and 2015 to establish databases. From spatial distribution pattern variations and type transformation trend, the spatial changes and dynamic transfers of landscape ecotypes in the source region were analysed by using the analytical methods of landscape ecological spatial patterns. Results show that the unique natural conditions of the source region are more harsh and fragile. There have been phenomena of grasslands deterioration, desertification and wetlands shrinking, and water yield in the upper reaches of the Yellow River has been decreasing in recent years. In the source region, the serious eco-environmental problems have been caused by climate changes, rodent damages and human activities. [ABSTRACT FROM AUTHOR]

The first county along the Yellow river, Madoi is the key region of the state natural protective source regions of Yangtze River, Lantsang River and Yellow River, its eco-environment and function in widespread attention. In support of the hardware and software system, based on GIS and remote sensing technology, this paper combined field investigation and laboratory analysis. Around 1990, 2000 and 2010, ten-phase remote sensing images are interpreted, and it is continuously monitored that Madoi wetlands have changed in the 20 years. Using wetland interpretation results and the area of the wetland types transfer matrix, it evaluates the changes of wetland area in the 20 years. With the meteorological and statistical data, this paper discussed the reason of the wetland changing in recent 20 years. The results of remote sensing monitoring and field investigation show that the overall trend of the wetland area changing increased after the first reducing in three times. In the first 10 years, swamp changes were the largest, followed by lakes and rivers; in the next 10 years, lake changes were the largest, followed by swamps and rivers. Natural factors which resulted in wetland changes of Madoi are climate changes, the permafrost environment changes, rodent rampant; man-made factors are overgrazing, irrational mining, fishing, hunting and development of tourism. [ABSTRACT FROM AUTHOR]

Positive electrode material LiNi1/2Mn1/2O2 was synthesized via the carbonate co-precipitation method and the hydroxide precipitation route to study the effects of the precursor on its structural and electrochemical properties. The results of X-ray diffraction and Rietveld refinement show that the carbonate precursor of Ni2+ and Mn2+ exhibits one phase at a pH of 8.5, while the hydroxide deposit separates into Ni(OH)2 and Mn(OH)2 phases under the same experimental conditions. LiNi1/2Mn1/2O2 material prepared from the hydroxide precursor shows 8.9% Li/Ni exchange and a large capacity loss of 11.3% in the first 10 cycles. By contrast, more uniform distribution of transition metal ions and stable Mn2+ in the carbonate precursor contribute to only 7.8% Li/Ni disorder in the obtained LiNi1/2Mn1/2O2, which delivers a reversible capacity of about 182 mAh g−1 at a current rate of 14 mA g−1 between 2.5 and 4.8 V. [ABSTRACT FROM AUTHOR]

This work is concerned with asymptotic properties of solutions to forward equations for singularly perturbed Markov chains with two small parameters. It is motivated by the model of a cost-minimizing firm involving production planning and capacity expansion and a two-level hierarchical decomposition. Our effort focuses on obtaining asymptotic expansions of the solutions to the forward equation. Different from previous work on singularly perturbed Markov chains, the inner expansion terms are constructed by solving certain partial differential equations. The methods of undetermined coefficients are used. The error bound is obtained. [Copyright &y& Elsevier]

Objectives: To propose a novel clinical classification system of gallbladder cancer, and to investigate the differences of clinicopathological characteristics and prognosis based on patients who underwent radical resection with different types of gallbladder cancer. Methods: The clinical data of 1 059 patients with gallbladder cancer underwent radical resection in 12 institutions in China from January 2013 to December 2017 were retrospectively collected and analyzed.There were 389 males and 670 females, aged (62.0±10.5)years(range:22-88 years).According to the location of tumor and the mode of invasion,the tumors were divided into peritoneal type, hepatic type, hepatic hilum type and mixed type, the surgical procedures were divided into regional radical resection and extended radical resection.The correlation between different types and T stage, N stage, vascular invasion, neural invasion, median survival time and surgical procedures were analyzed.Rates were compared by χ(2) test, survival analysis was carried by Kaplan-Meier and Log-rank test. Results: Regional radical resection was performed in 940 cases,including 81 cases in T1 stage,859 cases in T2-T4 stage,119 cases underwent extended radical resection;R0 resection was achieved in 990 cases(93.5%).The overall median survival time was 28 months.There were 81 patients in Tis-T1 stage and 978 patients in T2-T4 stage.The classification of gallbladder cancer in patients with T2-T4 stage: 345 cases(35.3%)of peritoneal type, 331 cases(33.8%) of hepatic type, 122 cases(12.5%) of hepatic hilum type and 180 cases(18.4%) of mixed type.T stage(χ(2)=288.60, P <0.01),N stage(χ(2)=68.10, P <0.01), vascular invasion(χ(2)=128.70, P <0.01)and neural invasion(χ(2)=54.30, P <0.01)were significantly correlated with the classification.The median survival time of peritoneal type,hepatic type,hepatic hilum type and mixed type was 48 months,21 months,16 months and 11 months,respectively(χ(2)=80.60, P <0.01).There was no significant difference in median survival time between regional radical resection and extended radical resection in the peritoneal type,hepatic type,hepatic hilum type and mixed type(all P >0.05). Conclusion: With application of new clinical classification, different types of gallbladder cancer are proved to be correlated with TNM stage, malignant biological behavior and prognosis, which will facilitate us in preoperative evaluation,surgical planning and prognosis evaluation.

Objective: To investigate and analyze the tinnitus' prevalence and its related systemic factors in health examination population in Dalian City. Method: The 1 596 people were chosen from the Physical Examination Center of our hospital from February 1, 2015 to April 1, 2015, the tinnitus questionnaire was performed, as well as Otolaryngology examination，the whole body check and blood test. We calculated the prevalence of tinnitus and analyzed the relationship of tinnitus with the gender,age,hypertension,hyperlipidemia, overweight, diabetes, renal dysfunction, anemia and other factors. Result: ①The total prevalence of tinnitus is about 18.8%(300/1 596) in Dalian's health examination population, and it is increased gradually with age( P <0.01). The prevalence of female is 20.6% (175/848), which is higher than the male(16.7%,125/748)( P <0.05).②Analyzed with the single factor Logistic regression analysis：female( OR =1.30), age( OR =1.04), hypertension( OR =2.30),hyperlipidemia( OR =1.49), overweight( OR =1.45), and diabetes( OR =1.75) were independent related factors for tinnitus( P <0.05); and analyzed with multi factor Logistic regression analysis: female( OR =1.27, P ＝0.085), age( OR =1.05, P ＜0.01),overweight( OR =1.46, P ＝0.007) were the main related factors. Conclusion: The prevalence of tinnitus is high in health examination population of Dalian；hypertension, hyperlipidemia and diabetes may be associated with tinnitus, all of female, overweight and age may be the mainly systemic factors., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Cerebral formation of the pathological isoform of the prion protein (PrP) is a crucial molecular event in prion diseases. The bank vole (Clethrionomys glareolus) is a rodent species highly susceptible to natural scrapie. The PrP gene of bank vole is polymorphic (Met/Ile) at codon 109. Here we show that homozygous 109Met/Met voles have incubation times shorter than heterozygous 109Met/Ile voles after experimental challenge with three different scrapie isolates. An HPLC-MS/MS method was optimized and applied to investigate whether in heterozygous animals both PrP allotypes are able to undergo pathological conversion. The results demonstrate that both allotypes of the prion protein participate to pathological deposition.

Creutzfeldt-Jakob disease (CJD) and other transmissible spongiform encephalopathies (TSEs) are characterised by the accumulation of a pathological conformer of PrP, named PrPsc. Molecular weight and glycosylation of the protease-resistant core of PrPsc (PrP27-30) are heterogeneous in different forms of TSEs. We analysed PrP27-30 glycotypes in a large number of TSE-affected patients: 50 sporadic CJD (sCJD), 1 iatrogenic CJD, 1 Gerstmann-Sträussler-Scheinker syndrome (GSS) with the Pro102Leu mutation of PrP, 3 familial CJD (fCJD) with the Glu200Lys mutation and, for the first time, 7 fCJD with the Val210ll3e mutation. All patients were screened for the polymorphic codon 129 of the PrP gene. PrP27-30 deglycosylation and PrPsc immunohistochemistry were performed in selected cases. We found that two PrP27-30 glycotypes (type 1A and type 2A) are produced in sCJD. Type 1A is more frequently associated with methionine than valine in position 129. Type 1A is also formed in Val210lle fCJD. In Glu200Lys fCJD and GSS patients, we found that PrP27-30 has the same mobility of type 1 but different glycosylation ratios (type 1B). Our findings indicate that the polymorphic residue 129 of PrP has a leading role in determining the proteinase degradation site of PrPsc while mutant residues 102 or 200 influence only the glycosylation pattern.