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Recently, the asymmetric bifunctionalization of alkenes has received much attention. However, the development of enantioselective alkoxyalkenylation has posed a considerable challenge and has lagged largely behind. Herein, we report a novel palladium-catalyzed enantioselective alkoxyalkenylation reaction, using a range of primary, secondary and tertiary γ-hydroxy-alkenes with alkenyl halides. By employing newly identified Xu-Phos (Xu8 and Xu9) with a suitable side-arm adjacent to the PCy2 motif, a series of allyl substituted tetrahydrofurans were obtained in good yields with up to 95% ee. Besides (E)-alkenyl halides, (Z)-alkenyl halide was also examined and provided the corresponding cis-product as a single diastereomer, supporting a stereospecific reductive elimination step. Moreover, deuterium labeling and VCD experiments were employed to determine a cis-oxypalladation mechanism, and DFT calculations helped us gain deeper insight into the side-arm effect on the chiral ligand. Finally, the practicability of this method is further demonstrated through a gram-scale synthesis and versatile transformation of the products.

Introduction: The objective of this study was to examine the association between type 2 diabetes mellitus (T2DM) and genes identified in previous genome-wide association studies (GWASs) in rural Han Chinese adults. Methods: This prospective study included 1,832 adults aged ≥18 years in Deqing without diabetes at baseline. The subjects were followed up for 8.7 years on average. We selected 45 susceptible tag single-nucleotide polymorphisms (SNPs) for T2DM that have been identified in GWASs and genotyped. A Cox model was constructed to calculate the adjusted hazard ratios (aHRs) for the association between SNPs and incident T2DM. Results: The incidence rate of T2DM was 12.0 per 1,000 person-years. After adjustment for covariates and a Bonferroni correction, rs17584499 of protein tyrosine phosphatase, receptor-type D (PTPRD), rs11257655 and rs10906115 of cell division cycle 123 gene (CDC123), and rs12970134 of melanocortin-4 receptor (MC4R) were significantly associated with incident T2DM. The aHRs for incident T2DM were 1.75 (95% confidence interval [CI]: 1.28–2.40) and 1.61 (95% CI: 1.27–2.04) in association with an increasing number of T alleles in rs17584499 and rs11257655 under an additive genetic model, and the aHR was 1.72 (95% CI: 1.33–2.22) with an increasing number of A alleles in rs10906115. The aHRs under the dominant model were 1.82 (95% CI: 1.25–2.66) for TT + CT versus CC of rs17584499 and 2.04 (95% CI: 1.47–2.86) for AA + AG versus GG of rs10966115. The aHRs under the recessive model were 2.99 (95% CI: 1.30–6.89) for TT versus CT + CC of rs17584499, 1.92 (95% CI: 1.39–2.70) for TT versus CT + CC of rs11257655, and 2.54 (95% CI:1.22–5.29) for AA versus AG + GG of rs12970134. In addition, an increased incidence of T2DM was significantly associated with the TA haplotype of rs11257655 and rs10906115 (aHR = 1.81, 95% CI: 1.12–2.92), while a decreased incidence was associated with the CG haplotype (aHR = 0.49, 95% CI: 0.35–0.68) and the CT haplotype of rs1111875 and rs5015480 (aHR = 0.61, 95% CI: 0.37–0.98). Conclusion: Variants of the PTPRD, CDC123, and MC4R genes were associated with the T2DM incidence in a rural Han Chinese population.

In recent years, it has been demonstrated that some susceptible gene loci of type 2 diabetes mellitus (T2DM) are not only associated with the susceptibility risk of T2DM, but also the modifying effects of lifestyle interventions. To further explore the modifying effects of the single nucleotide polymorphism (SNP) on the onset of T2DM and the reduction of blood glucose in response to lifestyle interventions among the high-risk population, we performed a lifestyle intervention study in two Deqing rural communities during the period from June to December in 2017. The intensive lifestyle interventions were conducted among the study subjects of the intervention group while those in the control group only received conventional and general health education. All participants were genotyped by the MassARRY system. This study showed that for SNP rs9502570, fasting blood glucose showed a significantly greater reduction for individuals with CC + CT genotype than those with TT genotype (近年来的研究发现,一些2型糖尿病(type 2 diabetes mellitus, T2DM)易感基因位点不仅与T2DM的发病风险有关,还会影响生活方式干预效果。为进一步探究T2DM易感基因单核苷酸多态性(single nucleotide polymorphism, SNP)位点对生活方式干预降低高危人群血糖应答效果的修饰作用,本课题组在德清农村社区开展了生活方式干预试验(2017年6月~12月,对干预组的研究对象进行强化生活方式干预,对照组仅接受常规健康知识宣教),并对研究对象进行SNP基因分型。研究发现,对于rs9502570,干预组中的CC+CT基因型人群的空腹血糖降低值显著高于TT基因型(

Poor sleep quality is prevalent and is associated with cognitive decline, impaired health, and reduced quality of life. There is a lack of studies about sleep quality and its potential risk factors among rural adults aged 45 years or above under rapid urbanization in China. In a cross-sectional survey conducted in Deqing County, China in 2015, we included 1584 adults 45+ years of age. Sleep quality was measured by using the Chinese version of the Pittsburgh Sleep Quality Index (CPSQI). Poor sleep quality was defined by a CPSQI global score > 5. Other data collected included sociodemographic and lifestyle factors as well as physical health. Logistic regression model was applied to assess factors influencing sleep quality by calculating crude odds ratio (cOR), adjusted OR (aOR), and their 95% confident intervals (CI). Of 1584 subjects, more than half were female with an average age of 58.9 ± 8.1 years. Their night sleep duration was 7.7 ± 1.2 h, sleep latency was 31.9 ± 32.0 min, and 17% of them could not fall asleep within half hour, averagely. The mean score of CPSQI was 4.4 ± 2.7. The prevalence of poor sleep quality was 27.7% (95% CI = 25.4–29.7%) overall, and there existed a significant sex difference—30.6% (95% CI = 27.7–33.7%) for women and 24.0% (95% CI = 20.9–27.2%) for men. Five domains of the CPSQI except for sleep efficiency and use of sleeping medication also showed a sex difference (p

Habitat fragmentation and loss is the main cause of species extinction; thus, the appropriate placement of protected areas is critical for saving vulnerable and threatened species. However, how to expand the existing protected areas network for improving conservation efficiency is a vital concern. We examined the Qinling Mountains — a widely recognized biogeographic treasure in China and East Asia, to identify key biodiversity areas (KBAs) and compare them with existing protected areas. We focused on 259 key protected wild plant and animal species and modeled species distributions with elevation and habitat preference. We then adapted two established algorithms (biodiversity hotspots of species richness [BHSR] and systematic conservation planning [SCP]) to identify priority areas, respectively. Results from these two algorithms addressed two conservation criteria: “represented” single species and “well-represented” species assemblages. SCP showed better performance (~ 90%) than BHSR (~ 78%) using the “represented” criterion covering a small portion (~ 8%) of the total region; conversely, BHSR showed better performance (~ 61%) than SCP (~ 55%) using the “well-represented” criterion. The overlapping priority areas of both methods could achieve an optimal conservation that met dual criteria, which is considered as the candidate KBAs in this study. Surprisingly, we found that 63% of KBAs are not co-occurring with existing national nature reserves (NNRs). We highlight the unoccupied KBAs as deserving additional protection, with a result that the expansion of NNRs to KBAs will increase overall conservation coverage and efficiency. The integrated method developed here can be used generally as a repeatable and quantitative assessment framework to be implemented in protected areas network expansion and planning, in China and beyond.

Theaceae is a plant family that mainly distributed in tropical or subtropical regions of Asia. Most species of Theaceae are endemic to China. Here, we used the herbarium collections aim to: a) detect the spatial species richness patterns; b) find out the geographical divisions and c) detect the environmental drivers of the dissimilarity patterns (β diversity). The current distributions of 193 Theaceae species were modeled using MaxEnt. Meanwhile, we calculated the pair wise dissimilarity between grid cell assemblages based on beta-sim index. An ordination was used to analyze the environmental drivers of the dissimilarity patterns. We found that the diversity hotspots for Theaceae species mainly locate in Fujian and Guangxi province. Two major divisions were suggested by the ordination analysis. The longitudinal division implies the climatic divergences between southeastern and southwestern China, while the latitudinal division implies the geographical barriers. For the species in southeastern China, the dissimilarity pattern is mainly driven by temperature annual range, annual precipitation and annual mean temperature. In the southwestern China, isothermality, precipitation seasonality and the rising altitude are the three main drivers. For effective conserving the Theaceae species, the protection of the micro-habitats and the high diversity areas on both sides of these divisions will be essential.

Climate change poses major new challenges to biodiversity conservation. Distribution ranges of species have been proven to be affected by climate anomalies. Detecting the extent of protected species response to climate change can help formulate flexible conservation strategies to overcome the changing climate. Using species distribution modeling and high resolution climate data, we simulated current distribution patterns of 233 protected plants in China. Those patterns were then projected into future suitable habitats for each species under nine climate change scenarios, with no migration or full migration hypotheses. Under the most extreme climate change scenario (CGCM-B2a), we evaluated species extinction risks. Sixteen percent of protected plants are expected to lose more than 30 % of their current ranges. By calculating areal shifts, hotspots for emigrants, immigrants, and persistent species were identified under climate change. Flexible conservation strategies were addressed for those regions. Those strategies strongly depend on the migration types of species and sensitivity of the hotspots to changing climate. In hotspots for emigrants, the main conservation strategy is ex situ protection; protected species from these regions should be stored in seed banks or botanical gardens. For hotspots of immigrants, enough space should be maintained for new species, and some measures are necessary to assist dispersal. For hotspots of persistent species, more natural reserves are needed. We highlight related fields that can help conserve protected species in the future, such as conserving the soil seed bank and understanding of the effects of migration ability and interactions between protected species.

Effective task scheduling is crucial for achieving high performance in heterogeneous computing environments. Whiling scheduling Out-Tree task graphs, many previous heterogeneity based heuristic algorithms usually require high scheduling costs and may not deliver good quality schedules with lower costs. Aiming at the characteristics of Out-Tree task graphs and the features of heterogeneous environments and adopting the strategy based on expected costs and task duplications, this paper proposes a greedy scheduling algorithm, which, at each scheduling step, tries to guarantee not to increase the schedule length, schedules the current task onto the used processor which minimizes its execution finish time; meanwhile, takes load balances into account to economize the use of processors. The comparative experimental results show that the proposed algorithm has higher scheduling efficiency and robust performance, which could produce better schedule which has shorter schedule length and less number of used processors.

Prestressed steel reinforced concrete structure, compared with other concrete structure has its unique advantages. So it is mainly used in large span and conversion layers. With the popularization of this structure,more attention should be payed on fire resistance performance. On the basis of reasonable assume,two steps model is used as concrete high strength calculation model. Simplified intensity decreased curve is used as rebar,steel and prestressed. Two ultimate bearing capacity formulas of prestressed steel reinforced concrete beam are established. One is for the beam whose tensile area is under fire, the other is for the beam whose compression area is under fire. Prestressed steel reinforced concrete structure has both prestressed concrete structure’s advantages and steel reinforced concrete structure ’s advantage. Steel reinforced concrete is used to improve the bearing capacity of the structure. Prestressed steel is used to improve the ultimate state of structure’s performance during normal use. Thereby structure’s performance is better to play. There are many similarities between prestressed steel reinforced concrete structure and steel reinforced concrete structure about fire resistance performance. Because of prestressed steel reinforced concrete structure’s own characteristics, there are still many problems about fire resistance. This paper mainly presented bending terminal bearing capacity of prestressed steel reinforced concrete beam under fire. Established simplified formulae for calculation, it is meet the engineering accuracy requirement.

Based on ABAQUS finite element analysis, nonlinear analysis about mechanical performance of reinforced concrete beam-column joints under thermal-stress coupling is carried out. This paper mainly research the temperature field distribution, the beam deformation of frame joints under fire and the influence of different parameters such as the axial compression ratio, beam layer thickness, reinforcement ratio on fire resistance of frame joint. Conclusions was drawn as: forming temperature gradient from the outside to the inside in frame joint; displacement of the end of the beam suddenly increase after plastic hinge appearing, the sudden destruction contains contingency; Due to the damage began from plastic hinge at the end of the beam, the axial compression ratio has less influence about fire resistance of frame joint; The thicker of beam layer thickness, the longer of joint refractory limit; the higher of reinforcement ratio ,the later of plastic hinge 's formation, that is good for fire resistance.

The zirconia-coated silica (ZrO2/SiO2) material was obtained by coupling layer-by-layer (LbL) self-assembly method and sol–gel technology, to take dual advantages of the suitable porous structure of SiO2 and basic resistance of ZrO2. Adenosine 5′-monophosphate (5′-AMP) was then self-assembled onto ZrO2/SiO2 via Lewis acid–base interaction, generating 5′-AMP-ZrO2/SiO2. The chromatographic properties of 5′-AMP-ZrO2/SiO2 were systemically studied by evaluating the effect of acetonitrile content, pH and buffer concentration in the mobile phase. The results demonstrated that the 5′-AMP-ZrO2/SiO2 possessed hydrophilic interaction chromatographic (HILIC) property comprising hydrophilic, hydrogen-bonding, electrostatic and ion-exchange interactions. For basic analytes, the column efficiency of ZrO2/SiO2 and 5′-AMP-ZrO2/SiO2 was superior to the bare ZrO2, and different selectivity was obtained after the introduction of 5′-AMP. For acidic analytes, good resolution was obtained on 5′-AMP-ZrO2/SiO2 while the analysis failed on the bare ZrO2 column owing to strong adsorption. Hence, the proposed 5′-AMP-ZrO2/SiO2 had great potential in analyzing acidic compounds in HILIC mode. It was an extended application of ZrO2 based SP.

Objective To establish an ideal CCl4 drug-induced liver injury model in vitro. Method Traditional method and improved method were adopted for preparing CCl4 injury liquid and drug-induced human liver HepG2 cell injury. Cell morphological change was observed under a bright-field microscope. The level of alanine aminotransferase (ALT) in supernatant was detected by biochemical method. 4-Methyl-tetrazolium (MTT) chromatometry was adopted for determining cell activity. Result The improved method showed better CCl4-induced injury effect than the traditional method. With the increase in the concentration of CCl4 injury liquid, the ALT level significantly increased, whereas the cell activity notably decreased. Particularly, 70% CCl4 injury liquid use for 4 hours could achieve the best injury effect. Conclusion The improved method could be used to establish an ideal CCl4 drug-induced liver injury model in vitro, which can lay foundation for further in vitro studies.

Relative parameters of upper limb bones, tibia and fibula were measured with computed radiography and used to establish the mathematical models for stature estimation of teenagers (from 14 to 18 years old) of Han population in Sichuan Province.The upper limb bones, tibia and fibula of 194 subjects were taken computerized radiography on normal position and were measured the lengths between relative landmarks. The body height of each subject was recorded. Linear regression equations for stature estimation between body height and the lengths of upper limb bones, tibia and fibula were established.Forty-two single linear regression equations and 4 multiple regression equations were obtained. The coefficients of correlation(r) were 0.689-0.917 and the standard errors of estimate(SE) were between 3.075 and 5.485 cm. All of the equations were statistically tested and diagnosed with good applicability.These equations could be used to estimate the body height of Sichuan Han population aged from 14 to 18. The lengths of the upper limb bones, tibia and fibula measured on the CR films could be useful to stature estimation of the adolescence and the forensic personal identification.