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Comparative analyses of mitogenomes in the social bees with insights into evolution of long inverted repeats in the Meliponini

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Zoological Research 2024年第1期45卷 160-175页

作者： yu-Ran Li Zheng-Wei Wang Richard T.Corlett wen-bin yu yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants&Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China

The insect mitogenome is typically a compact circular molecule with highly conserved gene ***,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the tRNAs,occur in different *** synapomorphies of mitogenome organizations can provide information for phylogenetic inferences,comparative analyses of mitogenomes have been given increasing ***,most studies use a very few species to represent the whole genus,tribe,family,or even order,overlooking potential variations at lower taxonomic levels,which might lead to some incorrect *** provide new insights into mitogenome organizations and their implications for phylogenetic inference,this study conducted comparative analyses for mitogenomes of three social bee tribes(Meliponini,Bombini,and Apini)based on the phylogenetic framework with denser taxonomic sampling at the species and population *** analyses revealed that mitogenomes of Apini and Bombini are the typical type,while those of Meliponini show diverse variations in mitogenome sizes and *** inverted repeats(IRs)cause significant gene rearrangements of protein coding genes(PCGs)and rRNAs in Indo-Malay/Australian stingless bee *** evolution analyses showed that the lineage with IRs have lower dN/dS ratios for PCGs than lineages without IRs,indicating potential effects of IRs on the evolution of mitochondrial *** finding of IRs and different patterns of gene rearrangements suggested that Meliponini is a hotspot in mitogenome *** conserved PCGs and rRNAs whose rearrangements were found only in the mentioned lineages within Meliponini,tRNA rearrangements are common across all three tribes of social bees,and are significant even at the species level,indicating that comprehensive sampling is needed to fully understand the patterns of tRNA rearrangements,and their implications for phylogenetic inference.

关键词： Social bees Phylogeny Mitogenome structure Gene rearrangement Inverted repeats

Al–9.00 %Si–0.25 %Mg alloys modified by ytterbium

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Rare Metals 2017年第2期36卷 95-100页

作者： Kun Jia wen-bin yu Jian-Min Yao Shuo Zhang Hao Wu School of Materials Science and Engineering Southwest University Guangzhou Automobile Group Motor Co Ltd

The effects of ytterbium（Yb） on microstructure and solidification behavior of Al-9.00%Si-0.25%Mg alloys were *** optical microscope（OM） and scanning electron microscopy（SEM）,it is found that the morphology of eutectic silicon changes from coarse plates to fine fibers by the addition of 0.7%wt *** addition,the grains of α-Al matrix are refined by Yb *** constitution of the alloy was analyzed by X-ray diffractometer（XRD） and energy dispersive spectroscopy（EDS）attached with SEM and mechanical properties were measured by hardness *** is concluded that the Yb atoms are incorporated into the silicon by the adsorption at the solid-liquid growth front to cause the modification of eutectic ***,the results of XRD and EDS analysis reveal that the Yb-containing phase forming in the alloys is Al_3Yb.

关键词： Al-9.00 %Si-0.25 %Mg alloy Yb Modification Eutectic silicon

Decoding the evolution and transmissions of the novel pneumonia coronavirus(SARS-CoV-2/HCoV-19)using whole genomic data

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Zoological Research 2020年第3期41卷 247-257页

作者： wen-bin yu Guang-Da Tang Li Zhang Richard T.Corlett Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesMenglaYunnan 666303China Henry Fok College of Biology and Agriculture Shaoguan UniversityShaoguanGuangdong 512005China College of Forestry and Landscape Architecture South China Agricultural UniversityGuangzhouGuangdong 510642China Chinese Institute for Brain Research Beijing 102206China

The outbreak of COVID-19 started in mid-December2019 in Wuhan, China. Up to 29 February 2020,SARS-CoV-2(HCoV-19/2019-nCoV) had infected more than 85 000 people in the world. In this study,we used 93 complete genomes of SARS-CoV-2 from the GISAID EpiFlu TM database to investigate the evolution and human-to-human transmissions of SARS-CoV-2 in the first two months of the *** constructed haplotypes of the SARS-CoV-2 genomes, performed phylogenomic analyses and estimated the potential population size changes of the virus. The date of population expansion was calculated based on the expansion parameter tau(τ)using the formula t=τ/2 u. A total of 120 substitution sites with 119 codons, including 79 non-synonymous and 40 synonymous substitutions, were found in eight coding-regions in the SARS-CoV-2 *** non-synonymous substitutions are potentially associated with virus adaptation. No combinations were detected. The 58 haplotypes(31 found in samples from China and 31 from outside China)were identified in 93 viral genomes under study and could be classified into five groups. By applying the reported bat coronavirus genome(bat-RaTG13-CoV)as the outgroup, we found that haplotypes H13 and H38 might be considered as ancestral haplotypes,and later H1 was derived from the intermediate haplotype H3. The population size of the SARS-CoV-2 was estimated to have undergone a recent expansion on 06 January 2020, and an early expansion on 08 December 2019. Furthermore,phyloepidemiologic approaches have recovered specific directions of human-to-human transmissions and the potential sources for international infected cases.

关键词： COVID-19 HCoV-19 SARS-CoV-2 Novel pneumonia outbreak Human-to-human transmission Phyloepidemiology

Rock engineering property of the high-steep open-pit slope and its stability

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Journal of Coal Science & Engineering(China) 2010年第1期16卷 35-40页

作者： PENG wen-bin yu Wei-jian School of Energy and Safety Engineering Hunan University of Science and Technology Xiangtan 411201 China

According to the rock engineering property and stability of high-steep open-pitslopes, various factors were collected on the basis of rock engineering system (RSE) theory,and the interaction matrix of stability evaluation was ***, the stabilityevaluation index (S_p) of the slope was put *** of the S_p value and the correspondingstable state were given on the basis of thirty-six *** is found that the followingrelationships exist: unstable (easy landslide): S_p***, the stability evaluation indexwas applied on the high-steep open-pit slope of one *** results and monitoringdata indicate that the index meets the necessity of the property of slope engineering, and ithas an important engineering purpose for landslide forecasting of high-steep slopes.

关键词： high-steep slope rock engineering system property stability evaluation open-pit mine

Pollen size strongly correlates with stigma depth among Pedicularis species

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Journal of Integrative Plant Biology 2016年第10期58卷 818-821页

作者： Xiang-Ping Wang wen-bin yu Shi-Guo Sun Shuang-Quan Huang College of Life Sciences Wuhan University Wuhan 430072China Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Mengla 666303China School of Life Sciences Central China Normal University Wuhan 430079China

Summary Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a posi-tive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species （Orobancha- ceae） in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin＇s functional hypothesis between pollen size and stigma depth.

关键词： Pedicularis phylogenetic comparative analysis pollen grain volume pollen tube growth stigma depth style length trait correlation

Effects of ytterbium addition and heat treatment on the mechanical properties and biocorrosion behaviors of Mg-Zn-Zr alloy

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Journal of Magnesium and Alloys 2020年第2期8卷 499-509页

作者： Lu Li Tao Wang yu Wang Cun-cai Zhang Hao Lv Hua Lin wen-bin yu Chu-jie Huang School of Materials and Energy Southwest UniversityChongqingChina Department of Clinical Laboratory Chongqing Ninth People's HospitalChongqing 400700PR China

Mechanical properties and biocorrosion behaviors in simulated body fluid(SBF)of newly developed Mg-5.8 Zn-0.5 Zr-x Yb(ZK60-X Yb,x=0,1.0,2.0wt%)magnesium alloys in the solution-treated(T4)and artificially-aged(T6)conditions were *** results of mechanical properties show that with Yb addition,the microhardness and the ultimate tensile strength(UTS)of the tested alloys are significantly increased despite a slight decrease in tensile elongation in both T4 and T6 ***,after the T6 treatment,the microhardness and the UTS of the samples were further improved,which was mainly attributed to the precipitation *** biocorrosion behaviors of the tested alloys were studied using electrochemical examinations and immersion *** results indicate that the biocorrosion resistance of the tested alloys is significantly improved by Yb addition in both T4 and T6 *** the corrosion resistance was slightly deteriorated after T6 treatment,the aged ZK60-2.0 Yb alloy still exhibited a favorable corrosion behavior,which was mainly ascribed to the corrosion barrier effect of a more compact and uniform protective film induced by the dispersed nano-scale *** measurements also confirmed these *** the favorable comprehensive performance in mechanical and biocorrosion behaviors,the T6 treated ZK60-2.0 Yb alloy may be considered as a promising candidate for biomedical applications.

关键词： Mg-Yb-Zn-Zr alloy Mechanical properties Biocorrosion behaviors Heat treatment Biomedical applications

Modification effect of Yb and Na_3PO_4 on microstructure of Mg_2Si/Mg-4Si alloy and mechanism

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China Foundry 2015年第6期12卷 440-445页

作者： Xiao-lin Wei Zheng Lian Huai-zhi Zhao Lu Li wen-bin yu Faculty of Materials and Energy Southwest University

The modification effects of ytterbium(Yb), Na_3PO_4 and Yb + Na_3PO_4 on primary Mg_2Si phase in Mg-4Si alloys were investigated by means of X-ray diffraction(XRD), optical microscopy(OM), scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS) analysis in this work. The results indicate that the morphology of the primary Mg_2Si phase apparently changes from coarse dendrites to fine dispersive polygonal particles and the mean size decreases from 276.6 μm to 7.1 μm, with combined modification of 0.8wt.% Yb and 2.64 wt.% Na_3PO_4. Such a morphological evolution results in improvement in the ultimate tensile strength and elongation of the alloys as compared to the base alloy. This may be attributed to the formation of the YbP particles that acted as the heterogeneous nucleation substrates for the primary Mg_2Si particles, resulting in a refined distribution of these precipitates. The results of XRD examination show that there was no reaction between Si and Yb or Na_3PO_4. Solo addition of Yb or Na_3PO_4 into the melt has no real modification effect on the microstructure, but the primary Mg_2Si particles and α-Mg phases become coarser than that in the unmodified alloy.

关键词： Mg alloy Yb Na3PO4 modification Mg2Si particles

Duodenal-jejunal bypass increases intraduodenal bile acids and upregulates duodenal SIRT1 expression in high-fat diet and streptozotocin-induced diabetic rats

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World Journal of Gastroenterology 2022年第31期28卷 4338-4350页

作者： Hai-Feng Han Shao-Zhuang Liu Xiang Zhang Meng Wei Xin Huang wen-bin yu Department of General Surgery Qilu HospitalCheeloo College of MedicineShandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND The mechanisms underlying diabetes remission after duodenal-jejunal bypass(DJB) remain elusive. In DJB surgery, the duodenum is excluded. However, the duodenum has emerged as an important regulator of glucose homeostasis, and elevated duodenal SIRT1 leads to improved hepatic insulin sensitivity. After DJB, bile acids(BAs) in the duodenum are not mixed and diluted by the ingested food. And activation of BA receptors promotes SIRT1 expression in many tissues. We hypothesized that BA-mediated upregulation of SIRT1 may contribute to diabetic control after *** To investigate the surgical effects of DJB on duodenal SIRT1 expression and uncover the potential crosslinks between BAs and *** Twenty diabetic rats were randomly allocated to the sham(n = 10) and DJB(n = 10) groups. Body weight, food intake, fasting blood glucose(FBG), serum and intraduodenal total BA(TBA) levels were measured accordingly. Oral glucose tolerance test(OGTT) and intraperitoneal pyruvate tolerance test(ip PTT) were performed to evaluate the effects of surgeries on systemic glucose disposal and hepatic gluconeogenesis. The key genes of BA signaling pathway in the duodenal mucosa, including farnesoid X receptor(FXR), small heterodimer partner(SHP), and Takeda G-protein-coupled receptor 5(TGR5) were evaluated by real-time quantitative polymerase chain reaction 8 wk postoperatively. The duodenal SIRT1, AMPK, and phosphorylated AMPK(p-AMPK) levels were evaluated by western blotting. Rat small intestine epithelial IEC-6 cells were treated with GW4064 and INT-777 to verify the effects of BAs on SIRT1 expression in *** The DJB group exhibited body weight and food intake comparable to those of the sham group at all postoperative time points. The FBG level and area under the curve for the OGTT and ip PTT were significantly lower in the DJB group. The DJB group exhibited higher fasting and postprandial serum TBA levels than the sham group at both 2 and 8 wk postoperativ

关键词： Duodenal-jejunal bypass Diabetes mellitus Bile acids Sirtuin 1 Duodenum High-fat diet

Three new species of Liparis s.l.(Orchidaceae:Malaxideae)from Southwest China based on morphological characters and phylogenetic evidence

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Plant Diversity 2021年第5期43卷 401-408页

作者： Ji-Dong Ya Dong-Liang Lin Zhou-Dong Han Lei Cai Zhi-Rong Zhang De-Ming He Xiao-Hua Jin wen-bin yu Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesLanhei Road 132HeilongtanKunmingYunnan650201China State Key Laboratory of Systematic and Evolutionary Botany and Herbarium Institute of BotanyChinese Academy of SciencesNanxincun20XiangshanBeijing100093China CAS Key Laboratory for Plant Biodiversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan650201China University of Chinese Academy of Sciences Beijing100049China yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Key Laboratory for Plant Diversity and Biogeography of East AsiaKunming Institute of BotanyChinese Academy of SciencesLanhei Road 132HeilongtanKunmingYunnan650201China wenshan National Nature Reserve Administration WenshanYunnan663000China Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenMenglaYunnan666303China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesMenglaYunnan666303China Southeast Asia Biodiversity Research Institute Chinese Academy of ScienceYezinNay Pyi Taw05282Myanmar

Liparis aureolabella and L mengziensis,two new species from the karst region of southwestern China,and L bingzhongluoensis,a new species from montane region in yunnan,are described and illustrated.L aureolabella is easily distinguished from its relatives by having abaxially purple leave with purple reticulate veins prominent adaxially,a lip auriculate at base,and falcate-lanceolate *** mengziensis is closely related to *** and ***,but differs from them by having an ovate to broadly ovate leaf,purple lip and apex connate along the *** bingzhongluoensis is similar to Liparis nanlingensis,but the new species is characterized by having a lip with two transparent ridges on its disc,longitudinally concave basal callus and triangular column *** analyses based on nuclear ribosomal ITS and plastid matK sequences showed that L aureolabella and L mengziensis are nested with L petiolata or L auriculata in a monophyletic clade.L bingzhongluoensis is sister to a clade formed by ***,***,L sasakii and ***,morphological comparisons strongly support that the three species as separated species newly to science.

关键词： Liparis Orchidaceae Taxonomy yunnan