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摘要： Fueled by various technical advances over the last two decades (e.g. high-throughput sequencing, genome editing, single-cell omics), the synthetic biology of mammalian cells is becoming increasingly sophisticated in the complexity of the engineered circuits. Complementing canonical transcription factor-based switches and these emerging protein-based devices, researchers have taken advantage of the rich RNA-based gene regulatory mechanisms in mammalian cells to design RNA devices that do not involve protein factors. Moreover, such efforts require understanding and engineering cell-cell communications and pattern formations. [Extracted from the article]

摘要： Since its first demonstration for mammalian gene editing, CRISPR/Cas technology has been widely adopted in research, industry, and medicine. Beyond indel mutations induced by Cas9 activity, recent advances in CRISPR/Cas have enabled DNA or RNA base editing. In addition, multiple orthogonal methods for the spatiotemporal regulation of CRISPR/Cas activity and repurposed Cas proteins for the visualization and relocation of specific genomic loci in living cells have been described. By harnessing the versatility of CRISPR/Cas-based devices and gene circuits, synthetic biologists are developing memory devices for lineage tracing and technologies for unbiased, high-throughput interrogation of combinatorial gene perturbations. We envision that such approaches will enable researchers to gain deeper insights into the translation of genotypes to phenotypes in healthy and diseased states.

摘要： Technologies harnessing CRISPR systems have been rapidly evolving and expanding the capacity of researchers for understanding of mammalian cell behavior and its underlying mechanisms through genome and epigenome manipulations. In this review, we summarized the recent developments of CRISPR-based technologies for genetic and epigenetic modifications that include engineering of Cas9 for PAM simplification, non-cleaving base editing tools and alteration of gene expression. Applications such as genome-wide screening methods or CRISPR-based DNA barcoding for cellular lineage tracking are highlighted. Anticipated and upcoming development for mammalian synthetic biology that includes organelle engineering is also discussed.

关键词： 水生动物病原微生物学   思政案例   天花病毒   疫苗  

摘要： 为了有效发挥课堂育人主渠道作用,提升水生动物医学专业学生的医学背景知识及人文素养,设计了水生动物病原微生物学的绪论部分中"天花病毒及其疫苗"的思政案例,让学生充分认识我国古代发明的人痘接种法对世界医学的重大贡献,以及人痘疫苗和牛痘疫苗的深厚渊源.该案例的实施,充分激发了学生的课程学习兴趣,增加了民族自豪感和自信心,弘扬了祖国传统文化,取得了良好的教学效果.

关键词： 思政教育   动物生物学   课程案例  

摘要： 教育是民族振兴、社会发展的基石,是提高国民素质、促进人类社会全面发展的根本途径。而大学生思想政治教育能培养大学生的思想道德素质,帮助其树立正确的世界观、人生观和价值观。动物生物学作为生命科学领域大一学生的第一门,也是第一学期唯一的一门专业课,是开展全方位课程思政的重要基地。本文以课程案例为基础,以日常学习、生活所见为切入点,探讨绪论、动物类群、寄生虫防治等教学章节中的思政元素,结合多样化的教学模式,深入挖掘专业知识体系中所蕴含的德育元素,将学生的专业素养、人文素养与思政素质有机融合,将思政教育渗透于专业课程教学体系中,同步提升大学生的思想政治素质和专业知识水平,助推新时代大学生全面发展,实现全方位育人的目标。

关键词： Orca   Dusky dolphin   Turbulent flow   Irradiation   Drag   Energy balance  

摘要： There is currently a growing interest in the area of drag reduction. In this work, the thermal effects of body color of some species of aquatics like Orcas and Dusky dolphins are investigated with respect to their swimming routes and geometric and behavioral characteristics. Considering the marine and atmospheric characteristics of these aquatics' routes, a thermal analysis is performed. The surrounding fluxes including the water flux, sun irradiation, and core temperature are considered in an energy balance to determine the skin temperature of the top side of the animal/organism's body. To study the effects of color on the surface temperature of the aquatic species, an experiment is carried out in the water on a flat plate with black and white color. Applying a turbulent analytical solution for heated boundary layers, it will be shown that the black color on the top of the bodies of these marine organisms is very efficient in terms of skin drag reduction. Moreover, to investigate the effects of the temperature on underwater skin friction drag reduction, the turbulent flow is simulated around a flat plate and a 2- dimensional modeled Killer whale at different temperatures. The results show that the top black body color of Orca and Dusky dolphin decreases their skin friction drag by 7%. This study will also provide the reason for this evolution of color scheme of other extremely fast marine animals, such as billfish, whales, and sharks. This method of drag reduction can be considered as one of the effective factors in skin drag reduction of underwater robots.

关键词： Climate change   Host-parasite interactions   Yersinia pestis   Sex-biased parasitism   Siphonaptera   Vector-borne disease  

摘要： While rodents frequently host ectoparasites that can vector zoonotic diseases, often little is known about their ectoparasite communities, even in places where hosts frequently interact with humans. Yosemite National Park is an area of high human-wildlife interaction and high potential zoonotic disease transfer. Nonetheless, relatively few studies have surveyed the flea communities on mammalian hosts in this area, and even fewer have characterized the environmental and host factors that predict infestation. We focused on two species, the alpine chipmunk (Tamias alpinus) and the lodgepole chipmunk (T. speciosus), which inhabit Yosemite and surrounding areas and can host fleas that vector plague. Because these hosts are exhibiting differential responses to environmental change, it is valuable to establish baselines for their flea communities before further changes occur. We surveyed fleas on these chipmunk hosts during three years (2013-2015), including in the year of a plague epizootic (2015), and documented significant inter-host differences in flea communities and changes across years. Flea abundance was associated with host traits including sex and fecal glucocorticoid metabolite levels. The average number of fleas per individual and the proportion of individuals carrying fleas increased across years for T. speciosus but not for T. alpinus. To better understand these patterns, we constructed models to identify environmental predictors of flea abundance for the two most common flea species, Ceratophyllus diktats mononis and Eumolpianus eumolpi. Results showed host-dependent differences in environmental predictors of flea abundance for E. eumolpi and C. diktats mononis, with notable ties to ambient temperature variation and elevation. These results provide insight into factors affecting flea abundance on two chipmunk species, which may be linked to changing climate and possible future plague epizootics.

关键词： Animal welfare   Animal suffering   Welfare biology   Effective altruism   Evolutionary biology  

摘要： Ng (Biol Philos 10(3):255-285, 1995. 10.1007/bf00852469) models the evolutionary dynamics underlying the existence of suffering and enjoyment and concludes that there is likely to be more suffering than enjoyment in nature. In this paper, we find an error in Ng's model that, when fixed, negates the original conclusion. Instead, the model offers only ambiguity as to whether suffering or enjoyment predominates in nature. We illustrate the dynamics around suffering and enjoyment with the most plausible parameters. In our illustration, we find surprising results: the rate of failure to reproduce can improve or worsen average welfare depending on other characteristics of a species. Our illustration suggests that for organisms with more intense conscious experiences, the balance of enjoyment and suffering may lean more toward suffering. We offer some suggestions for empirical study of wild animal welfare. We conclude by noting that recent writings on wild animal welfare should be revised based on this correction to have a somewhat less pessimistic view of nature.

关键词： Eggs   Embryos   Nurses   Estuaries   Larvae   Gastropods   Histology   Ingestion  

摘要： Among calyptraeid gastropods, males become females as they get older, and egg capsules containing developing embryos are maintained beneath the mother's shell until the encapsulated embryos hatch. Crepipatella dilatata is an interesting biological model considering that is an estuarine species and thus periodically exposed to elevated environment-physiological pressures. Presently, there is not much information about the reproductive biology and brooding parameters of this gastropod. This paper describes field and laboratory observations monitoring sex changes, brooding frequencies, sizes of brooding females, egg mass characteristics, and embryonic hatching conditions. Our findings indicate that C. dilatata is a direct-developing protandric hermaphrodite, changing from male to female when individuals were between 18 and 20 mm in shell length. At our study site in Quempillen estuary, females were found to be brooding almost continuously throughout the year, having an average maximum of 85% of simultaneous brooding, with a short rest from April through June. No relationship was found between the number of capsules per egg mass and the size of the brooding female. However, capsule size and the number of embryos and nurse eggs were strongly related to female size. The offspring hatched with an average shell length > 1 mm. About 25% of the hatched capsules were found to contain both metamorphosed (juveniles) and non-metamorphosed (veliger) individuals. The sizes of the latter were < 1000 mu m. The length of hatching juveniles was inversely related to the number of individuals per capsule, which seems related to differences in the availability of nurse eggs per embryo. Although fecundity per reproductive event of this species is relatively low (maximum approx. 800 offspring per egg mass) compared with those of calyptraeid species showing mixed development, the overall reproductive potential of C. dilatata seems to be high considering that females can reproduce up to 5 tim