Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan Mountains

Biogeographical barriers to gene flow are central to plant phylogeography.In East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across both.Here we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern China.Demographic and migration hypotheses were tested using coalescent-based approaches.Limited historical gene flow was observed between the western and eastern groups of P.rotundifolia,but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central group.Wind-borne pollen and seeds may have facilitated the dispersal of P.rotundifolia following prevalent northwest winds in the spring.We also found that the Hengduan Mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of P.rotundifolia.Ecological niche modeling suggested that P.rotundifolia has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 Ka.The phylogeographic pattern of P.rotundifolia reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate history.This study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas.

Conservation genomic investigation of an endangered conifer,Thuja sutchuenensis,reveals low genetic diversity but also low genetic load

Endangered species generally have small populations with low genetic diversity and a high genetic load.Thuja sutchuenensis is an endangered conifer endemic to southwestern China.It was once considered extinct in the wild,but in 1999 was rediscovered.However,little is known about its genetic load.We collected 67 individuals from five wild,isolated T.sutchuenensis populations,and used 636,151 SNPs to analyze the level of genetic diversity and genetic load in T.sutchuenensis to delineate the conservation units of T.sutchuenensis,based on whole transcriptome sequencing data,as well as target capture sequencing data.We found that populations of T.sutchuenensis could be divided into three groups.These groups had low levels genetic diversity and were moderately genetically differentiated.Our findings also indicate that T.sutchuenensis suffered two severe bottlenecks around the Last Glaciation Period and Last Glacial Maximum.Among Thuja species,T.sutchuenensis presented the lowest genetic load and hence might have purged deleterious mutations efficiently through purifying selection.However,distribution of fitness effects analysis indicated a high extinction risk for T.sutchuenensis.Multiple lines of evidence identified three management units for T.sutchuenensis.Although T.sutchuenensis possesses a low genetic load,low genetic diversity,suboptimal fitness,and anthropogenic pressures all present an extinction risk for this rare conifer.This might also hold true for many endangered plant species in the mountains all over the world.

Clinical characteristics and prognosis of traumatic basal ganglia hematomas: A retrospective analysis of 40 cases

AIM： To retrospectively analyze the pathogenesis, clinical characteristics, treatment and prognostic characteristics in patients with traumatic basal ganglia hematomas （TBGH）. METHODS： A retrospective analysis of the clinical data was performed in 40 patients with TBGH who were selected from 1 250 patients with closed brain injury, who admitted to the Department of Neurosurgery of Shangqiu First People＇s Hospital from January 1990 to January 2004. The pathogenesis, clinical characteristics and signs, results of radiological examination, treatment and prognostic characteristics were analyzed. The patients all had definite history of brain injury, manifested by neurological functional disturbance to different extent after brain injury, and basal ganglia hemorrhage was identified by CT after brain injury, and hemorrhagic volume were more than or equal to 2 mL. Totally 34 males and 6 females were enrolled, aged 16-72 years and 28 cases of them were younger than 40 years old. The prognosis of the patients was evaluated with Glasgow outcome scale （GOS） at 6 months after injury, and GOS scoring standard was 1-5 points （1 for dead; 2 for vegetative survival, long-term coma, manifestations of decorticate rigidity or decerebrate rigidity; 3 for severely disabled, should be look after by others; 4 for moderately disabled, be able in self-care; 5 for good recovery, adults can work and study）. RESULTS： The enrolled cases accounted for 3.20% of the 1250 patients with closed brain injury admitted at the same period. ① The causes of injury included traffic accident in 36 cases, fall in 2 cases, and assault in 2 cases. ②At admission, the Glasgow coma scale （GCS） scores were as follow： 13-15 scores （mild） in 10 cases, 9-12 scores （moderate） in 20 cases, and 3-8 scores （severe） in 10 cases. Hemiplegia presented in 37 cases, aphasia in 20 cases, conscious disturbance in 10 cases, unilateral mydriasis in 6 cases, and decerebrate rigidity in 2 cases. ③ TBGH was detected by CT within 30 minutes to 24 hours after injury in 37 cases, and delayed TBGH was diagnosed by serial CT reexamination at 24 to 48 hours after injury in 3 cases. Apart from the TBGH, signs of diffuse axonal injury （DAI） were observed in 22 cases and the criterion of CT diagnosis was that apart from TBGH, small hemorrhagic loci were found in the deep white matter of the hemisphere, corpus callosum, dorsolateral quadrants of the midbrain and the upper pons, internal capsule, basal ganglia area, intraventricle, and cerebellum, etc., but there was no obvious mass effect （clinically manifested by conscious disturbance immediately after brain injury, and primary coma lasted for longer than 6 hours）. Secondary intraventricular hemorrhage occurred in 19 cases, acute subdural hematoma in 3 cases, acute epidural hematoma in 1 case, cerebral contusion in 7 cases, and diffuse cerebral swelling in 3 cases. TBGH located at contralateral to the side of impact in 29 cases. The volume of TBGH was 3-9 mL in 8 cases, 10-19 mL in 10 cases, 20-29 mL in 12 cases, and more than 30 mL in 9 cases. ④Ten patients underwent surgical treatment, including TBGH were evacuated by craniotomy in 7 cases, drained by drilling hole in 2 cases, and hematoma drainage combined with extraventricular drainage in 1 case. 30 patients received conservative treatment, including hyperbaric oxygen treatment in 22 cases. ⑤At 6 months after injury, good recovery obtained in 10 cases （25%）, moderately disabled in 17 cases （42.5%）, severely disabled in 2 cases （5%） and dead in 11 cases （27.5%） respectively. CONCLUSION： In our study, the proportion of TBGH in closed brain injury was 3.2%, and it had a higher incidence of disability. Most of the patients were young people and injured in traffic accident, and TBGH mostly oc- curred at contralateral to the side of impact. The patients suffered from hemiplegia and long-term coma, incidence rate of diffuse axonal injury was higher, but conscious disturbance was milder. Conservative treatment was mainly applied in our study. CT scan can not only establish the position, volume of TBGH, but also establish if it combines with other intracranial injury, and it is helpful to detect delayed TBGH.

Screening of New High Quality and High Yield Sweet Potato Varieties in Zaozhuang of Shandong Province

[Objectives]To compare the growth period,dry matter content and yield of 12 different sweet potato varieties,so as to screen out new sweet potato varieties with high yield,high quality and high dry matter content suitable for cultivation in Zaozhuang of Shandong Province.[Methods]Field random arrangement,three replicates,and field observation were adopted,and data were surveyed and summarized.[Results]There were significant differences in the maturity period between varieties.Longshu 9,Hongxiangjiao,Sushu 8,Yanshu 25,and Yanshu 0747 in the fresh eating group were mature earlier,and Yuzi 7 was mature later;Xushu 32 in the starch group was mature earlier,while Xushu 22(ck),Shangshu 19,Jishu 25,and Jishu 98 had moderate maturity period,and Jixu 23 was mature later.The difference in the yield between the fresh eating group and the starch group reached a very significant level.In the fresh eating group,Yanshu 25 had the highest yield,followed by Longshu 9,and then Yanshu 0747;in the starch group,Jishu 98 had the highest yield,followed by Shangshu 19,and then Jixu 23.Besides,there were significant differences in the dry matter content between varieties.In the fresh eating group,Yuzi 7 had the highest dry matter content(30.4%),followed by Yanshu 25(28.1%),and then Yanshu 0747(28.1%);in the starch group,Xushu 32 had the highest dry matter content(33.6%),followed by Jishu 25(32%),and then Jishu 98(31.5%).[Conclusions]Combining the maturity period,yield,dry matter content,appearance,taste and unique ecological conditions in Zaozhuang area,the varieties suitable for cultivation in Zaozhuang area were screened:in the fresh eating group,it was Yanshu 25 and Longshu 9;in the starch group,it was Jishu 98,Shangshu 19,and Jixu 23.

Integrating Zeolite and Layered Double Hydroxide for Highly Selective Catalytic Production ofγ-Valerolactone

The production ofγ-valerolactone(GVL)from biomass derivatives levulinic acid(LA)based on acidbase metallic catalysts offers a sustainable pathway to the synthesis of valuable chemicals and biofuels.However,the development of efficient metallic catalysts with tunable Lewis acid–base and Brønsted acid sites remains a challenge.Herein,for the first time,we integrated zeolite and layered double hydroxide(LDH),in a core–shell structure,wherein zeolite and CoFe-LDH provided the Brønsted acidic sites and Lewis acid sites,respectively.Meanwhile,oxygen vacancies(OV_(x))acting as Lewis bases were generated on the surface of LDH via Ga doping.An efficient cascade catalytic reaction from LA to GVL was successfully achieved over the designed Beta@LDH-OVx catalyst,affording a superior conversion of LA(>99.9%)and an impressive selectivity to GVL(89.18%).Importantly,the“memory effect”of LDH endowed the catalyst with excellent regeneration of metal active sites.Density functional theory calculations revealed that the introduced OVx facilitated the adsorption of carbonyl oxygen in LA and boosted the production of GVL through the synergistic effect of acid/base sites in the composite catalyst.This work presents a rational design route for the construction of multifunctional catalysts by coupling zeolites and LDHs for highly selective catalytic conversion of biomass.

一种新型有机质子响应荧光分子的合成在实验教学中的设计与探索

本实验将最新的科研热点——有机发光材料引入实验教学,开发了基于一个荧光分子二甲氨基苯乙烯基苯并噁唑的合成实验,并考查了其质子响应性质。本实验反应温和易控,操作简单,现象明显,绿色环保,并且可以用于模块化教学,拆分成多个环节实验,适合不同学时的实验教学要求,既可培养学生的基本操作,又能激发学生的实验兴趣,锻炼学生的综合能力。

Phosphorus Behavior at Sediment-Water Interface in Coastal Wetland

[Objective] The aim was to explore the role of coastal wetlands in phosphorus fixation in the Yellow River Delta.[Method] The research analyzed phosphorus behavior at sediment-water interface by static water column test. [Result] The research concluded that phosphorus concentration was in the range of 0.051-0.322 mg/L in overlying water, and phosphorus was effectively removed by degradation and adsorption. The static water column test has demonstrated that phosphorus concentration of coastal wetlands plays the role of accumulation when phosphorus concentration is lower than 7 mg/L in overlying water of coastal wetlands. It is notable that substrates of overlying water all perform well in adsorption, and the adsorption reaches saturation if the concentration goes up to 10 mg/L. [Conclusion] Coastal wetlands would significantly adsorb and degrade phosphorus in overlying water, controlling phosphorus within a lower range.

Phylotranscriptomics of Swertiinae(Gentianaceae)reveals that key floral traits are not phylogenetically correlated

Establishing how lineages with similar traits are phylogenetically related remains critical for understanding the origin of biodiversity on Earth.Floral traits in plants are widely used to explore phylogenetic relationships and to delineate taxonomic groups.The subtribe Swertiinae(Gentianaceae)comprises more than 350 species with high floral diversity ranging from rotate to tubular corollas and possessing diverse nectaries.Here we performed phylogenetic analysis of 60 species from all 15 genera of the subtribe Swertiinae sensu Ho and Liu,representing the range of floral diversity,using data from the nuclear and plastid genomes.Extensive topological conflicts were present between the nuclear and plastome trees.Three of the 15 genera represented by multiple species are polyphyletic in both trees.Key floral traits including corolla type,absence or presence of lobe scales,nectary type,nectary position,and stigma type are randomly distributed in the nuclear and plastome trees without phylogenetic correlation.We also revealed the likely ancient hybrid origin of one large clade comprising 10 genera with diverse floral traits.These results highlight the complex evolutionary history of this subtribe.The phylogenies constructed here provide a basic framework for further exploring the ecological and genetic mechanisms underlying both species diversification and floral diversity.

组织获取位置和样本破损程度对胎盘来源造血干细胞质量的影响

目的研究胎盘造血干细胞取样位置、破损程度与制备质量之间的关系,为临床胎盘样本收集及建立高质量的胎盘造血干细胞样本库提供指导和依据。方法根据胎盘造血干细胞制备位点取样后进行STR检测,分析不同取样位点的母血嵌合情况,确定精确取样位置。同时通过对胎盘破损程度进行分级,对不同破损级别的样本进行制备后的总有核细胞数量(TNC)、CD34^(+)CD45^(dim)流式、粒细胞-巨噬细胞集落形成单位(CFU-GM)等各项质量检测,分析不同破损程度的胎盘样本各项质量指标情况。根据是否满足正态分布,符合正态分布的多组比较采用One-wayANOVA分析法,两组间比较采用t检验,不符合正态分布的,两组间比较采用非参数检验。结果STR检测结果分析,与取样点1比较,取样点2外周血细胞嵌合率[(39.57±4.56)%比(22.37±3.61)%]升高,取样点3外周血细胞嵌合率[(2.17±0.17)%比(22.37±3.61)%]降低,差异有统计学意义(P<0.01);与取样点3比较,取样点1和2外周血细胞嵌合率升高。与未破损组比较,三级破损组平均TNC数量[(5.52±0.351)×10^(8)比(6.92±0.83)×10^(8)]降低,差异具有统计学意义(P<0.01)。与未破损组比较,一级破损组CD34CD45dim细胞流式指标TNC的比例升高,二级、三级破损组占比降低,差异无统计学意义。与未破损组比较,二级、三级破损组CFU-GM集落平均总数降低,差异有统计学意义。结论不同的制备取样位置其母血嵌合率差异较大,尽量在靠近胎儿面位置取样有助于获得高质量的胎盘造血干细胞。同时通过对胎盘样本进行破损定级,胎盘破损程度越高,制备获取的胎盘TNC、CD34^(+)CD45^(dim)流式细胞数量、CFU-GM集落数量越低,其有效的造血干细胞数量降低,提示胎盘采集应尽量完整。

主流分子钟定年方法的原理、误差来源和使用建议

近年来,分子钟定年方法(molecular dating methods)得以广泛运用,为宏观进化研究尤其是生物多样性及其格局形成历史的相关研究提供了不可或缺且十分详尽的进化时间框架。贝叶斯方法(Bayesianmethods)和马尔可夫链蒙特卡罗方法(Markov chain Monte Carlo)可容纳多维度、多类型的数据和参数设置,因此以BEAST、PAML-MCMCTree等软件为代表的贝叶斯节点标记法(Bayesian node-dating methods)逐渐成为分子钟定年方法中最为广泛使用的类型。贝叶斯框架的优势之一在于其可以利用复杂模型考虑各种不确定性因素,但是该类方法中各类模型和参数的设置都可能引入误差,从而影响进化分化时间估算的可靠性。本文介绍了贝叶斯分子钟定年方法的原理和主要类型,并以贝叶斯节点标记法为例,重点讨论了分子钟模型、化石标记的选择与放置、采样频率及化石标记点年龄先验分布等因素对节点定年的影响;提供了贝叶斯时间树构建软件的使用建议、节点年龄的讨论原则和不同模型下时间树的比较方法,针对常见的引起节点年龄潜在高估和低估风险的情况作了分析并给出了合理化建议。我们认为,合理整合多种贝叶斯方法和模型得出的结果并从中择优,能够提高定年结果的可靠性;研究人员应对时间树构建结果与其参数设置的关系开展讨论,从而为其他学者提供参考;化石记录的更新与分子钟定年方法的改进应同步不断跟进。

Pressure induced convergence of conduction bands in Al doped Mg_(2)Si: Experiment and theory

High-pressure and high-temperature(HPHT)synthesis provides an effective way to tune the band structure of materials and improve their electronic properties.To investigate the influence of synthesis pressure on electronic properties,Mg_(1.97)Al_(0.03)Si samples were synthesized using the HPHT method.The maximum effective mass 0.92me is obtained for the sample prepared with the synthesis pressure of 3 GPa,leading to the biggest Seebeck coefficient
201.3 mV/K at room temperature.Meanwhile,the 3 GPa sample obtains the higher electron carrier concentration and electrical conductivity,resulting in nearly overall enhancement of power factor.The Density Functional Theory(DFT)calculations evidences that the Conduction Bands Minimum(CBM)can be tuned effectively by applied pressure and the convergence of the CBM leads to a larger effective mass of DOS,which are beneficial to the enhancement of power factors.These results indicate that high-pressure is a powerful tool to tune Mg_(1.97)Al_(0.03)Si band structures.

Multi-category diagnostic accuracy based on logistic regression

We provide a detailed review for the statistical analysis of diagnostic accuracy in a multi-category classification task.For qualitative response variables with more than two categories,many traditional accuracy measures such as sensitivity,specificity and area under the ROC curve are no longer applicable.In recent literature,new diagnostic accuracy measures are introduced in medical research studies.In this paper,important statistical concepts for multi-category classification accuracy are reviewed and their utilities are demonstrated with real medical examples.We offer problem-based R code to illustrate how to perform these statistical computations step by step.We expect such analysis tools will become more familiar to practitioners and receive broader applications in biostatistics.Our program can be adapted to many classifiers among which logistic regression may be the most popular approach.We thus base our discussion and illustration completely on the logistic regression in this paper.

Dual occupations of sulfur induced band flattening and chemical bond softening in p-type S_(y)Co_(4)Sb_(12-2y)S_(2y) skutterudites

The electronegative filling in skutterudites not only broadened the scope of filling atoms,but also facilitated the preparation of p-type skutterudites.However,the introduction of a single sulfur atom in the Co_(4)Sb_(12) cannot be achieved without charge compensation through the traditional equilibrium method.In the present study,the dual occupations of S-atoms by self-charge compensation were shown as the most stable forms under high pressure,and a series of p-type S_(y)Co_(4)Sb_(12-2y)S_(2y) skutterudites was successfully prepared by high-pressure-high-temperature(HPHT)method.The electronic structures and transport properties of as-obtained materials were investigated,and the related mechanisms were explored.The results suggested that the presence of S-impurities led to flattening of the electronic band that led to a higher Seebeck coefficient.The S-doped Co_(4)Sb_(12) displayed lower elastic modulus,elastic constant,and Debye temperature,thus indicating the chemical bond softening in skutterudites.The thermal conductivities of S_(y)Co_(4)Sb_(12-2y)S_(2y) compounds reduced monotonously with the increase in Scontent.This study provides a new and promising avenue for optimizing the thermoelectric properties of p-type Co_(4)Sb_(12).

Molecular signatures of parallel adaptive divergence causing reproductive isolation and speciation across two genera

Parallel evolution of reproductive isolation(PERI)provides strong evidence for natural selection playing a fundamental role in the origin of species.However,PERI has been rarely demonstrated for well established species drawn from different genera.In particular,parallel molecular signatures for the same genes in response to similar habitat divergence in such different lineages is lacking.Here,based on whole-genome sequencing data.