FISH ASSEMBLAGE RESPONSES TO DIFFERENT SECONDARY CHANNEL DESIGNS IN THE LOWER MISSISSIPPI RIVER,U.S.A.:A TEMPLATE FOR RIVER RESTORATION

The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Louisiana-Mississippi, U.S.A.) upstream to rkm 1504(Missouri-Kentucky, U.S.A.). Four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).Fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. Fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. Conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. Future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent secondary channels in selected river reaches. However, temporary secondary channels also contain unique fish species, and also appear to be important sites of riverine primary production. Restoration strategies should consider a balance of both secondary channel types, which should support the greatest biodiversity for the LMR ecosystem.     

微生物在水环境污染物降解中的应用

每年有大量来自工业、农业、养殖业和城市污水处理厂的废水被排入到水环境中,因此,地球上的水环境面临大量来自生活废水、工农业废水、非法排放的废水及其它废水的污染物质(如抗生素、杀虫剂,除草剂、烃等)的严重挑战,特别是近年来随着集约化养殖的发展,废水污染问题日益突出,并且随着分析手段的进步,能够检测到被排入水环境中的化学污染物质也越来越多,这些化学污染物对水环境中的生物产生有害影响.但是,微生物在污染控制上具有许多重要的作用.因此,本文对微生物在水环境污染物降解中的应用进行了评论.结果表明微生物主要是应用在水产养殖水中,而在其它的水体系(如河、湖、海)的应用较少.     

Effects of environmental stressors on stem cells

Environmental toxicants are ubiquitous,and many are known to cause harmful health effects.However,much of what we know or think we know concerning the targets and long-term effects of exposure to environmental stressors is sadly lacking.Toxicant exposure may have health effects that are currently mischaracterized or at least mechanistically incompletely understood.While much of the recent excitement about stem cells(SCs)focuses on their potential as therapeutic agents,they also offer a valuable resource to give us insight into the mechanisms and risks of toxicant effects.Not only as a response to the increasing ethical pressure to reduce animal testing,SC studies allow us valuable insight into the true effects of human exposure to environmental stressors under controlled conditions.We present a review of the history of publications on the effects of environmental stressors on SCs,followed by a consolidation of the literature over the past five years on a subset of key environmental stressors of importance to human health and their effects on both embryonic and tissue SCs.The review will make constructive suggestions as to areas of toxicant research where further studies are needed,as well as making indications of the potential utility for advancing knowledge and directing research on environmental toxicology.     

走进内蒙

2015年8月1日,我们每一个人收拾好行囊,整装待发,在邓涛老师带领下踏上了去往内蒙古的征程,拉开了探索灰色生命之旅的序幕. 队伍由两辆车、8人组成,我们早晨7点从中国科学院古脊椎动物与古人类研究所出发,披着清晨的阳光,摆脱城市的拥挤,缓缓地“逃离”了北京城.直到抵达张北之后我们的车子才能像矫健的马儿一样驰骋在广袤的公路上,沿途没有了城市的喧闹,没有了交通的堵塞,伴随我们的只有那一眼望去蓝蓝的天空、随风摆动的小草,以及那迷人的风景,偶尔打开车窗,一股凉爽的清风扑面而来,沁人心脾.经过一路的颠簸,我们在傍晚时刻到达锡林浩特,当地文物保护站的同志为我们安顿好了一切.     

例谈2007年高考"现代生物科技专题"

通过现代生物科技专题及相关高考试题的介绍与分析,以开拓学生视野,增强科技意识,激发学生探索生命奥妙和热爱生物科学的情感,为进一步学习现代生物学奠定基础.同时,借助现代生物科技专题作试题背景,具有能力的开放性和情境的新颖性,也有利于考查和培养学生独立获取新知识、收集和处理信息的能力.所选试题涉及现代生物科技前沿的领域有:基因工程、细胞工程、蛋白质工程、癌症和克隆技术等,均体现出对现代生物技术发展的关注.     

Formidable females redux:male social integration into female networks and the value of dynamic multilayer networks

The development of multilayer network techniques is a boon for researchers who wish to understand how different interaction layers might influence each other,and how these in turn might influence group dynamics.Here,we investigate how integration between male and female grooming and aggression interaction networks influences male power trajectories in vervet monkeys Chlorocebus pygerythrus.Our previous analyses of this phenomenon used a monolayer approach,and our aim here is to extend these analyses using a dynamic multilayer approach.To do so,we constructed a temporal series of male and female interaction layers.We then used a multivariate multilevel autoregression model to compare cross-lagged associations between a male's centrality in the female grooming layer and changes in male Elo ratings.Our results confirmed our original findings:changes in male centrality within the female grooming network were weakly but positively tied to changes in their Elo ratings.However,the multilayer network approach offered additional insights into this social process,identifying how changes in a male's centrality cascade through the other network layers.This dynamic view indicates that the changes in Elo ratings are likely to be short-lived,but that male centrality within the female network had a much stronger impact throughout the multilayer network as a whole,especially on reducing intermale aggression(i.e.,aggression directed by males toward other males).We suggest that multilayer social network approaches can take advantage of increased amounts of social data that are more commonly collected these days,using a variety of methods.Such data are inherently multilevel and multilayered,and thus offer the ability to quantify more precisely the dynamics of animal social behaviors.     

Plant infection by two different viruses induce contrasting changes of vectors fitness and behavior

Insect-vectored plant viruses can induce changes in plant phenotypes,thus influencing plant-vector interactions in a way that may promote their dispersal according to their mode of transmission (i.e.,circulative vs.noncirculative).This indirect vector manipulation requires host-virus-vector coevolution and would thus be effective solely in very specific plant-virus-vector species associations.Some studies suggest this manipulation may depend on multiple factors relative to various intrinsic characteristics of vectors such as transmission efficiency.In anintegrative study,we tested the effects of infection of the Brassicaceae Camelina sativa with the noncirculative Cauliflower mosaic virus (CaMV)or the circulative Turnip yellows virus (TuYV)on the host-plant colonization of two aphid species differing in their virus transmission efficiency:the polyphagous Myzus persicae,efficient vector of both viruses,and the Brassicaceae specialist Brevicoryne brassicae,poor vector of TuYV and efficient vector of CaMV.Results confirmed the important role of virus mode of transmission as plant-mediated effects of CaMV on the two aphid species induced negative alterations of feeding behavior (i.e.,decreased phloem sap ingestion)and performance that were both conducive for virus fitness by promoting dispersion after a rapid acquisition.In addition,virus transmission efficiency may also play a role in vector manipulation by viruses as only the responses of the efficient vector to plant-mediated effects of TuYV,that is,enhanced feeding behavior and performances,were favorable to their acquisition and further dispersal.Altogether,this work demonstrated that vector transmission efficiency also has to be considered when studying the mechanisms underlying vector manipulation by viruses.Our results also re- inforce the idea that vector manipulation requires coevolution between plant,virus and vector.     

Increased monoamine oxidase activity and imidazoline binding sites in insulin-resistant adipocytes from obese Zucker rats

BACKGROUND Despite overt insulin resistance,adipocytes of genetically obese Zucker rats accumulate the excess of calorie intake in the form of lipids.AIM To investigate whether factors can replace or reinforce insulin lipogenic action by exploring glucose uptake activation by hydrogen peroxide,since it is produced by monoamine oxidase(MAO)and semicarbazide-sensitive amine oxidase(SSAO)in adipocytes.METHODS 3H-2-deoxyglucose uptake(2-DG)was determined in adipocytes from obese and lean rats in response to insulin or MAO and SSAO substrates such as tyramine and benzylamine.14C-tyramine oxidation and binding of imidazolinic radioligands[3H-Idazoxan,3H-(2-benzofuranyl)-2-imidazoline]were studied in adipocytes,the liver,and muscle.The influence of in vivo administration of tyramine+vanadium on glucose handling was assessed in lean and obese rats.RESULTS 2-DG uptake and lipogenesis stimulation by insulin were dampened in adipocytes from obese rats,when compared to their lean littermates.Tyramine and benzylamine activation of hexose uptake was vanadate-dependent and was also limited,while MAO was increased and SSAO decreased.These changes were adipocyte-specific and accompanied by a greater number of imidazoline I2 binding sites in the obese rat,when compared to the lean.In vitro,tyramine precluded the binding to I2 sites,while in vivo,its administration together with vanadium lowered fasting plasma levels of glucose and triacylglycerols in obese CONCLUSION The adipocytes from obese Zucker rats exhibit increased MAO activity and imidazoline binding site number.However,probably as a consequence of SSAO down-regulation,the glucose transport stimulation by tyramine is decreased as much as that of insulin in these insulin-resistant adipocytes.The adipocyte amine oxidases deserve more studies with respect to their putative contribution to the management of glucose and lipid handling.     

Stem cell therapy applied for digestive anastomosis: Current state and future perspectives

BACKGROUND Digestive tract resections are usually followed by an anastomosis.Anastomotic leakage,normally due to failed healing,is the most feared complication in digestive surgery because it is associated with high morbidity and mortality.Despite technical and technological advances and focused research,its rates have remained almost unchanged the last decades.In the last two decades,stem cells(SCs)have been shown to enhance healing in animal and human studies;hence,SCs have emerged since 2008 as an alternative to improve anastomoses outcomes.AIM To summarise the published knowledge of SC utilisation as a preventative tool for hollow digestive viscera anastomotic or suture leaks.METHODS PubMed,Science Direct,Scopus and Cochrane searches were performed using the key words“anastomosis”,“colorectal/colonic anastomoses”,“anastomotic leak”,“stem cells”,“progenitor cells”,“cellular therapy”and“cell therapy”in order to identify relevant articles published in English and Spanish during the years of 2000 to 2021.Studies employing SCs,performing digestive anastomoses in hollow viscera or digestive perforation sutures and monitoring healing were finally included.Reference lists from the selected articles were reviewed to identify additional pertinent articles.METHODS Given the great variability in the study designs,anastomotic models,interventions(SCs,doses and vehicles)and outcome measures,performing a reliable meta-analysis was considered impossible,so we present the studies,their results and limitations.RESULTS Eighteen preclinical studies and three review papers were identified;no clinical studies have been published and there are no registered clinical trials.Experimental studies,mainly in rat and porcine models and occasionally in very adverse conditions such as ischaemia or colitis,have been demonstrated SCs as safe and have shown some encouraging morphological,functional and even clinical results.Mesenchymal SCs are mostly employed,and delivery routes are mainly local injections and cell sheets followed by biosutures(sutures coated by SCs)or purely topical.As potential weaknesses,animal models need to be improved to make them more comparable and equivalent to clinical practice,and the SC isolation processes need to be standardised.There is notable heterogeneity in the studies,making them difficult to compare.Further investigations are needed to establish the indications,the administration system,potential adjuvants,the final efficacy and to confirm safety and exclude definitively oncological concerns.CONCLUSION The future role of SC therapy to induce healing processes in digestive anastomoses/sutures still needs to be determined and seems to be currently far from clinical use.     

向日葵生殖生长不同时期向光运动日变化的观察

通过观测可以确定向日葵的确具有明显跟随太阳旋转的向光性,但处于不同时期的向日葵有很大差异:处于花蕾早期的向日葵从日出到日落跟随太阳由东经南再向西运动且有明显的滞后现象.盛花期的向日葵花盘基本固定朝向东方,不跟随太阳运动,但仍有小范围偏转.     

吉林省蓝藻门两新种

报道了采自吉林省的蓝藻门2个新种：具翼单歧藻Tolypothrix alata,脆弱真枝藻Stigonema fragile。     

蓝藻门两新种蓝藻门两新种

报道了采自黑龙江省五大连池的蓝藻门2个新种：绿刺星球藻、雅致伪枝藻。     

蓝藻门两新种

报道了采自黑龙江省五大连池的蓝藻门2个新种:绿刺星球藻、雅致伪枝藻。     

吉林省蓝藻门真枝藻属三新种

报道了采自吉林省的蓝藻门真枝藻属三新种：波纹真枝藻,拟小真枝藻,悦目真枝藻。波纹真枝藻丝体边缘常呈波纹状,主丝体宽 80～100 μm;拟小真枝藻主丝体宽 60～80 μm,分枝宽 30～45 μm,其胶被幼时黄褐色,成熟后无色;悦目真枝藻的匍匐丝体由数条丝体通过侧面粘合在一起,每条丝体宽 15～26 μm。     

吉林省蓝藻门两新种

描述了采自长白山永青电站的蓝藻门新植物灰白伪枝藻（Scytonema cineraceum C.L.Zhou et Xiao, sp. nov.）, 其原植体丛生，垫状，近半球形，灰褐色。蓝藻门新植物岩生蓝柄藻(Cyanostylon rupestris L .H.Lü et Xiao, sp. nov.)，采自吉林省集安市五女峰，植物团块为较柔软的胶质小皮壳状堆积体，棕黄色或棕红色。     

云南白蚁二新种：等翅目：白蚁科

本文描述产于云南的白蚁科２新种：章凤马歪白蚁Ｍａｌａｙｓｉｏｃａｐｒｉｔｅｒｍｅｓ ｚｈａｎｇｆｅｎｇｅｒｓｉｓ ｓｐ．ｎ．、江城瘤歪白蚁Ｍｉｒｏｃａｐｒｉｔｅｒｍｅｓ ｊｉａｎｇｃｈｅｎｇｅｒｓｉｓ ｓｐ．ｎ。在读者讨论中,作者等认为,李桂祥等描述的中国马歪白蚁Ｍ．ｓｉｎｉｃｕｓ Ｌｉ ｅｔ Ｘｉａｏ应转移入华歪白蚁属Ｓｉｎｏｃａｐｒｉｔｅｒｍｅｓ Ｐｉｎｇ ｅｔ Ｘｕ,新组合为中国华歪白蚁Ｓｉ     

潜叶蜂族研究(膜翅目:叶峰科)(英文)

本文记述中国潜叶蜂族Fenusini6属8种,其中包括2新属6新种及4新组合种：大眼郑潜叶蜂Zhenginamegommagen．etsp．nov,吕氏华潜叶蜂Sinofeunsaluigen．etsp．nov,黑鳞丝潜叶蜂Messanigrotegulasp．nov,痕缝脊潜叶蜂Parnavestigialissp．nov,沟缝脊潜叶蜂Parnadistinctasp．nov,黄首原潜叶蜂Profenusaxanthocephalasp．nov．;槭树雅潜叶蜂Anafsnusaacericola（Xiao1992）comb．nov。恢复臀潜叶蜂属AfusaMalaise,将ParafenusaZhelochovtsev（1976）降为AfusaMalaise1964的次异名,原Paarafenusa属下的种类移入Afusa属,建立3个新组合：Afusapruni（Zhelochovtsev1976）comb．nov,Afusacerasi（Zhelochovtsev1976）comb．nov,Afusamaharibiana（Zhelochovtsev1976）comb．nov。新属新种附有主要形态特征图。文中还编制了潜叶蜂族的已知底检索表和Profenusa,Anafeausa,Parna属的已知种检索表。雅潜叶蜂属Anafenusa和脊潜叶蜂属Parna为中国新纪录属。迄今,潜叶蜂族已知24属约60种;中国已记述12属22种。     

中国东北辽宁省西部几种中生代化石木

对产自辽宁省西部中生代化石木进行了解剖学研究。经鉴定,它们是：朝阳原始云杉型木（新种）（Ｐｒｏｔｏｐｉｃｅｏｘｙｌｏｎ ｃｈａｏｙａｎｇｅｎｓｅ Ｄｕａｎ ｓｐ．ｎｏｖ．）,西部南洋杉型木（Ａｒａｕｃａｒｉｏｘｙｌｏｎ ｓｉｄｕｇａｗａｅｎｓｅ Ｓｈｉｍａｋｕｒａ）,巴图南洋杉型木（新种）（Ａｒａｕｃａｒｉｏｘｙｌｏｎ ｂａｔｕｅｎｓｅ Ｄｕａｎ ｓｐ．ｎｏｖ．）和辽西紫杉型木（新种）（Ｔａｘｏｘ     

云南瑞丽果实蝇属二新种记述(双翅目,实蝇科,寡鬃实蝇亚科)

记述采自中国云南瑞丽的果实蝇属(双翅目,实蝇科)2新种,拟黑颜果实蝇 Bactrocera(Zeugodacus)proprediaphraWang,Xiao et Chen,sp.nov.和瑞丽果实蝇 Bactrocera(Bactrocera)ruiliensis Wang,Xiao et Chen,sp.nov..2新种的正模及其中的4个副模标本保存于中国科学院动物研究所,其余的副模标本保存于瑞丽出入境检验检疫局.     

中国玉兰属两新种

描述了中国木兰科玉兰属两新种,奇叶玉兰(Yulania mirifolia D.L.Fu,T B Zhao etZ.X.Chen,sp.nov.)和青皮玉兰(Yulania viridula D.L.Fu,T B Zhao et G.H.Tian,sp.nov.)的形态特征和分布情况,并与近缘种进行了比较。