MicroRNAs Play Significant Roles in Pathogenesis of HBV-Related Diseases

MicroRNAs (miRNAs) comprise an important class of small (about 22 nt) conserved nonprotein-coding RNAs that specifically regulate cellular gene expression at the post-transcriptional level. Increasing researches showed that miRNAs have emerged as critical regulators involved in diverse physiological and pathological processes, in-cluding such as proliferation, differentiation and development, apoptosis and patho-gen-host interactions. This review summarizes the crucial roles of miRNAs in replica-tion of the Hepatitis B virus (HBV) and the mechanism underlying dysregulation of miRNAs in HBV-associated diseases. miRNAs are emerged as essential regulators of HBV replication and pathogenesis. To a certain extent, miRNA is a new promising biomarker and useful strategy for diagnosis of HBV-related diseases.

Remanufacturing Scheme Design for Used Parts Based on Incomplete Information Reconstruction

The different conditions of use of a component result in a variety of damage levels.Therefore,excluding differences in shape and size,used parts show a high degree of uncertainty regarding failure characteristics,quality conditions,and remaining life,which seriously affects the efficiency of a remanufacturing scheme design.Aiming to address this problem,a remanufacturing scheme design method based on the reconstruction of incomplete information of used parts is proposed.First,the remaining life of the reconstructed model is predicted by finite element analysis,and the demand for the next life cycle is determined.Second,the scanned 3D damage point cloud data are registered with the original point cloud data using the integral iterative method to construct a missing point cloud model to achieve the restoration of geometric information.Then,according to reverse engineering and laser cladding remanufacturing,the tool remanufacturing process path can be generated by the tool contact point path section line method.Finally,the proposed method is adopted for turbine blades to evaluate the effectiveness and feasibility of the proposed scheme.This study proposes a remanufacturing scheme design method based on the incomplete reconstruction of used part information to solve the uncertain and highly personalized problems in remanufacturing.

Effects of odors on behaviors of captive Amur leopards Panthera pardus orientalis

Captive environments often fail to resemble the wild environment in respects of limited space,unchanging habitat,lack of stimulus and contingency. Common animal welfare problems which occur in captive animals include low behavioral diversity,abnormal behavior and excessive inactivity. Environmental enrichment,as an effective strategy to tackle these problems and promote mental health of captive animals,has been recognized as an important principal for captive animal management. Among all the enrichment techniques,olfactory enrichment is a simple and effective method for improving the well-being of the olfactory sensitive felids. Behavioral problems were observed in six Amur leopards Panthera pardus orientalis at Beijing Zoological Garden. These were held in the older type exhibits which have now been rebuilt. These behaviors include stereotypic behavior and excessive inactivity caused by the spatially limited enclosures with low levels of stimuli. To determine the effects of predator,prey,and herb odors as potential enrichment materials for captive leopards,we conducted olfactory enrichment experiments for the leopards and tested the effects of nutmeg Myristica fragrans,feces of roe deer Capreolus capreolus and urine of Amur tiger Panthera tigris altaica to test for an increase in behavioral repertoire and activity. Odors provided in this study were also believed to improve the psychological and physiological health of individuals. To standardize the method of presentation the odors were introduced to the enclosures by rubbing or spraying onto a clean towel. Our results show that the selected three odors effectively increased the behavioral diversity. Ten new behavior types were observed in the nutmeg experiment,eight in the feces of roe deer experiment and six in the tiger urine experiment. Among the three odors,cats responded to nutmeg for the longest duration,followed by tiger urine and feces of roe deer. Leopards showed more play behavior in presence of nutmeg while more investigatory behavior in presences of feces of roe deer and tiger urine. Providing novel odors increased the spatial use of the exhibit and the animal's increased use of the logs,sleeping platforms and bars in the cages. Novel odors also significantly increased the overall activity of the leopards,but the effects were diminished in about three

Spatial Distribution Pattern of the Steppe Toad-headed Lizard(Phrynocephalus frontalis) and Its Influencing Factors

Spatial distribution patterns are associated with life history and behavioral adaptations of animals. For studying the spatial distribution pattern of the steppe toad-headed lizard(Phrynocephalus frontalis) and its influencing factors,we conducted experiments in Hunshandake Sandy Land in Inner Mongolia,China in July 2009. By calculating the clustered indices,we found that the lizard was aggregately distributed when the sampling quadrat was smaller than 10 m × 10 m,and uniformly distributed when it was greater than 10 m × 10 m. The Nearest Neighbor Rule showed a clustering distribution pattern for P. frontalis and the distribution pattern was quadrat-sampling dependent. Furthermore,the cluster was determined by environmental factors when the sampling quadrat was smaller than 20 m × 20 m,but it was determined by both environmental factors and characteristics of the lizard when it was larger than 20 m × 20 m. Our results suggested that the steppe toad-headed lizards tended to aggregate into suitable habitat patches in desert areas. Additionally,we discussed that the lizard aggregation could be potentially used as an indictor of movement of sand dunes.

Diet, Food Intake of Phrynocephalus frontalis (Agamidae) and Its Potential Role in Desert Habitat

We examined the dietary diversity and food intake of Phrynocephalus frontalis, compared the difference of insect diversity in the natural habitats with different lizard densities, and discussed the potential role of this lizard in the desert ecosystem. The results show that： （1） arthropodans of the orders Coleoptera, Hymenoptera and Hemiptera were major dietary components of P. frontalis; （2） coleoptera larvae always formed the predominant component of lizard diets; （3） dietary diversities of P. frontalis were not significantly different between summer and autumn or between the two sexes; （4） the similarity in trophic niches between seasons was 0.756, whereas the similarity in trophic niches between sexes was 0.994; （5） stomach content weight of lizards varied significantly among different seasons, but there was no significant difference in stomach content weight between sexes; （6） insect diversity differed significantly among the groups of the habitat with different degrees of lizard density, and the habitat with moderate lizards density had the highest insect diversity. We infer that P. frontalis prey mainly on insects and change their diet and food intake with season; males and females consumed similar preys in types and weights. As an important predator, P. frontalis could affect the insect community in the arid ecosystem of Hunshandak Desert on the Mongolian Plateau.

Effects of Sand Grain Size on Habitat Selection in Steppe Toad-headed Lizard(Phrynocephalus frontalis)

To understand the effects of sand grain size on habitat selection, we conducted a field study on the steppe toad-headed lizard in Hunshandake Desert northern China. Methods of mark-recapture and transect survey were used to investigate the density of steppe toad-headed lizards and the environmental variables. The comparison on lizard densities among the habitats with different environmental factors revealed that： 1） population density of the steppe toad-headed lizard differed significantly among the habitats with different sand grain size indexes（SGSIs, representing roughness of sand substrate）： the highest lizard density was found in the group with an SGSI of 〉 0.30, whereas the lowest density was found in the group with an SGSI of 0–0.15; and 2） vegetation cover, soil moisture, invertebrate diversity index, and abundance had no significant effects on the lizard density. These results implied that the sand grain size was the most important determinant of habitat selection for steppe toad-headed lizards in Hunshandake Desert. Steppe toad-headed lizards could avoid structural habitats that have negative effects on their maximal sprinting capabilities. Considering the changing sand grain size in the development phase of sand dunes, the sand lizard could be used as an indicator of the process of desertification.

Arc Discharge Device Working at Atmospheric Pressure

Arc in vacuum is one of the important methods used to prepare carbon materials. However, the use of vacuum increases the cost of the arc method. This paper introduces an arc discharge device working at atmospheric pressure. The current-limiting resistor, capacitor and inductor make the discharge gentle. The electrode temperature can be adjusted from 2040 K to 3673 K. Carbon nanofibres were prepared at the electrode temperature of 3645 K by using this device.

国家濒危物种红色名录的生物多样性保护意义

IUCN濒危物种红色名录与国家濒危物种红色名录都是物种灭绝风险的测度,前者是全球性评估,后者则是国别研究。IUCN濒危物种红色名录预警了全球物种的濒危状况,为全球生物多样性研究提供了大数据;国别红色名录确定了各国物种受威胁状况,填补了前者的知识空缺,两份名录互为补充。目前对国家濒危物种红色名录重视不够。基于如下原因,应当重视国别濒危物种红色名录的意义:(1)国家是濒危物种保护的行为主体,物种在一个国家的生存状况是确定其保护级别、开展濒危物种保育的依据;(2)对于仅分布于一个国家的特有物种来说,其国别濒危物种红色名录等级即是其全球濒危等级;(3)对于跨国境分布的物种来说,国别濒危物种红色名录等级则确定了该物种在本国的生存状况;(4)结合IUCN濒危物种红色名录,国别濒危物种红色名录为建立跨国保护地、保护迁徙物种的栖息地与跨国迁徙洄游通道提供依据;(5)国别濒危物种红色名录所特有的"区域灭绝"等级,反映了一个物种边缘种群在该国的区域灭绝,恢复"区域灭绝"物种是该物种原分布国重引入保育工作的重点;(6)国别濒危物种红色名录提供了该国物种编目、分类、分布和生存状况的最新信息。然而,国别濒危物种红色名录的重要性在许多情况下被忽视了。目前正值全球新冠肺炎大流行,人们正在重新审视人与野生动物的关系。我国将修订有关野生动物保护与防疫法法律以及《国家重点保护野生动物名录》,防控新的人与野生动物共患疾病再次暴发。对于确定国家重点保护野生动物物种名录来言,物种受威胁程度是物种列为国家重点保护物种的特征之一。重视国别红色名录有特别的意义。

加入《迁徙物种公约》,促进全球迁徙动物保护

自然界中,一些野生动物为了觅食或繁殖,会随着季节沿固定或非固定路线从一处栖息地转换到另一处栖息地。这些野生动物常常跨越国界进行长距离的迁徙或洄游,其生存容易受到迁徙或洄游路线阻断、过度捕猎/捕捞、气候变化以及觅食或繁殖栖息地丧失和退化的威胁(Wilcove&Wikelski,2008)。

新疆阿勒泰地区爬行动物区系及多样性海拔分布格局

中国阿勒泰地区是北半球中纬度地区的特殊区域,与俄罗斯、哈萨克斯坦、蒙古接壤,境内有平原、沙漠和山地三大地貌特征。2014–2016年,我们先后3次对阿勒泰地区爬行动物资源开展了实地调查,共采集到392号爬行动物标本。经鉴定隶属1目6科16种,结合文献资料,共计1目8科23种,均为古北界物种,其中中亚型17种,古北型6种,表现出中亚亚界与欧洲–西伯利亚亚界间的过渡性质。爬行动物Shannon-Wiener多样性指数、Simpson优势度指数随海拔分布呈带有一个中峰的低海拔高原格局,在第2海拔段(500–600 m)达到峰值;均匀度指数总体呈现递增格局,第15海拔段(1,800–1,900 m)达到最大值;丰富度则呈现一种波动的递减格局,峰值在第10海拔段(1,300–1,400 m)。3种环境因子对这种格局的独立解释力较低,但综合作用的解释力较强,其中海拔与年均温这两个因子的综合作用对物种多样性影响程度最大。

阿尔泰山中蒙边境地区的雪豹及其保护意义

雪豹(Pantherauncia)是猫科豹亚科动物,生活在林线以上的高山带和亚高山带。据全球雪豹及其生态系统保护计划(GlobalSnowLeopard&EcosystemProtectionProgram,GSLEP)估计,目前全球雪豹为4,000–6,500只,其分布跨越12个国家,分布面积约为180万km2,其中60%以上在中国(Snow Leopard Working Secretariat,2013,https://www.globalsnow leopard.org/)。雪豹分布在高海拔陡峭偏远的山地环境,种群密度低(Xu et al,2008),行踪诡秘,加之其烟灰色的花纹易于融入周围的裸岩环境,限制了雪豹研究的开展。

阿尔泰山前荒漠两种沙蜥体况指数特征及其与生态因子的关系

为明确奇台沙蜥(Phrynocephalus grumgrzimailoi)和旱地沙蜥(P.helioscopus)体况指数的年龄性别特征,及其与海拔、年均温、年降水量、平均日较差之间的关系,我们测量了阿勒泰地区84只奇台沙蜥与176只旱地沙蜥的体况数据,用log体重/log头体长表示体况指数。结果显示:(1)旱地沙蜥与奇台沙蜥间体况指数差异显著。(2)旱地沙蜥体况指数雌雄两性差异不显著,奇台沙蜥体况指数雌雄两性差异显著。(3)两种蜥蜴成体与亚成体间体况指数均差异明显。(4)以月份为单位,奇台沙蜥体况指数月份差异明显,旱地沙蜥体况指数月份差异不明显。(5)年均温对奇台沙蜥体况指数有重要影响,而年降水量为补充因子,主要通过与其他生态因子组合发挥作用,海拔对旱地沙蜥体况指数有影响。这些结果表明两种沙蜥对不同环境因子的反应不同,在不同环境的适应度也不同。

Numerical model and experimental demonstration of high precision ablation of pulse CO_2 laser

To reveal the physical mechanism of laser ablation and establish the prediction model for figuring the surface of fused silica, a multi-physical transient numerical model coupled with heat transfer and fluid flow was developed under pulsed CO2laser irradiation. The model employed various heat transfer and hydrodynamic boundary and thermomechanical properties for assisting the understanding of the contributions of Marangoni convention,gravitational force, vaporization recoil pressure, and capillary force in the process of laser ablation and better prediction of laser processing. Simulation results indicated that the vaporization recoil pressure dominated the formation of the final ablation profile. The ablation depth increased exponentially with pulse duration and linearly with laser energy after homogenous evaporation. The model was validated by experimental data of pulse CO2laser ablation of fused silica. To further investigate laser beam figuring, local ablation by varying the overlap rate and laser energy was conducted, achieving down to 4 nm homogenous ablation depth.

Bird diversity and the conservation value of a new Ramsar site:Guangdong Haifeng Wetlands, China

Wetlands are critical habitats for birds.However,wetlands are being degraded at an accelerating rate due to global human activity,and a disproportionate fraction of wetland-dependent bird species are in decline.We evaluated the conservation value of a new Ramsar site,Guangdong Haifeng Wetlands,China,for birds,by comparing bird communities(using line transect data)in 3 different districts:Gongping,Dongguan Lian’anwei and Dahu.We recorded 139 species of birds,including 26 species that are protected at a national level.Dahu had the highest species richness and diversity,whereas Dongguan Lian’anwei had the highest abundance of birds and the lowest species diversity.Finally,Gongping had both the lowest species richness and the lowest abundance.The ende-mism of constituent species differed among districts,and the bird communities were complementary.There were significant seasonal differences in the species richness and the number of individuals.Spring had the highest species richness and diversity.The present study identifies the high conservation value of Haifeng Wetlands for both waterbirds and terrestrial birds.Our findings suggest that conservation efforts in Haifeng Wetlands and other wetlands should focus not only on wintering migratory birds,but also on resident birds.To accomplish effective conservation,we should consider the reserve and surrounding wetlands as a whole,incorporating ecological research,education and local economic development.

A carbon efficiency upgrading method for mechanical machining based on scheduling optimization strategy

Low-carbon manufacturing(LCM)is increasingly being regarded as a new sustainable manufacturing model of carbon emission reduction in the manufacturing industry.In this paper,a two-stage low-carbon scheduling optimization method of job shop is presented as part of the efforts to implement LCM,which also aims to reduce the processing cost and improve the efficiency of a mechanical machining process.In the first stage,a task assignment optimization model is proposed to optimize carbon emissions without jeopardizing the processing efficiency and the profit of a machining process.Non-dominated sorting genetic algorithm II and technique for order preference by similarity to an ideal solution are then adopted to assign the most suitable batch task of different parts to each machine.In the second stage,a processing route optimization model is established to plan the processing sequence of different parts for each machine.Finally,niche genetic algorithm is utilized to minimize the makespan.A case study on the fabrication of four typical parts of a machine tool is demonstrated to validate the proposed method.

Attracted by the same sex, or repelled by the opposite sex? -Sexual segregation in Pere David's deer

Sexual segregation behavior has attracted deep interest of zoologists in recent years. People have put forward many hypotheses to explain the phenomenon. We recommended two indices for measuring the intensity of aggregation and sexual segregation in animals, and applied those measurements to the study of aggregation and sexual segregation in free-ranging Pere David’s deer. We quantified the aggregation and segregation behavior with those methods and compared the intensities of sexual segregation in different seasons with statistic means. At the same time, the Nutritional Strategy Hypothesis, the Social-factor Hypothesis and Reproductive Strategy Hypothesis were tested in the study. We discovered that aggregation in free ranging Pere David’s deer was high in winter but low in summer. Sexual segregation in free ranging Pere Danid’s deer is caused by the reproductive strategy of different sexes, the highest degree of sexual segregation was found in the breeding season not the non-breeding season in the