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.     

Applications of stem cells and bioprinting for potential treatment of diabetes

Currently, there does not exist a strategy that can reduce diabetes and scientists are working towards a cure and innovative approaches by employing stem cellbased therapies. On the other hand, bioprinting technology is a novel therapeutic approach that aims to replace the diseased or lost β-cells, insulin-secreting cells in the pancreas, which can potentially regenerate damaged organs such as the pancreas. Stem cells have the ability to differentiate into various cell lines including insulinproducing cells. However, there are still barriers that hamper the successful differentiation of stem cells into β-cells. In this review, we focus on the potential applications of stem cell research and bioprinting that may be targeted towards replacing the β-cells in the pancreas and may offer approaches towards treatment of diabetes. This review emphasizes on the applicability of employing both stem cells and other cells in 3 D bioprinting to generate substitutes for diseased β-cells and recover lost pancreatic functions. The article then proceeds to discuss the overall research done in the field of stem cell-based bioprinting and provides future directions for improving the same for potential applications in diabetic research.     

Behavioral and neural auditory thresholds in a frog

Vocalizations play a critical role in mate recognition and mate choice in a number of taxa, especially, but not limited to, orthopterans, frogs, and birds. But receivers can only recognize and prefer sounds that they can hear. Thus a fundamental question linking neurobiology and sexual selection asks-what is the threshold for detecting acoustic sexual displays? In this study, we use 3 methods to assess such thresholds in tdngara frogs: behavioral responses, auditory brainstem responsesz and multi unit electrophysiological recordi ngs from the midbrain.We show that thresholds are lowest for multiunit recordings (ca. 45 dB SPL), and then for behavioral responses (ca. 61 dB SPL), with auditory brainstem responses exhibiting the highest thresholds (ca. 71 dB SPL). We discuss why these estimates differ and why, as with other studies, it is unlikely that they should be the same. Although all of these studies estimate thresholds they are not measuring the same thresholds;behavioral thresholds are based on signal salienee whereas the 2 neural assays estimate physiological thresholds. All 3 estimates, however, make it clear that to have an appreciation for detection and salienee of acoustic signals we must listen to those signals through the ears of the receivers.     

中国省级行政区生态环境可持续性评价

从自然条件、人类胁迫、生态环境效应和社会响应4个主题出发,构建了包含28个指标的中国省级行政区生态环境可持续性评价指标体系,并通过专家调查和层次分析法为各主题层中的指标赋权.分别用各主题层中的指标和对应的权重,采用加权平均法构建自然条件(NSI)、人类胁迫(HPI)、生态环境效应(EEI)和社会响应(SRI)4个分指数,然后用这4个分指数通过灰色关联法构建综合生态环境可持续性指数(CEI),对我国各省级行政区生态环境可持续性进行评价.同时论文通过主成分分析法和相关分析法分析造成各指数地域差异的主导因素和评价中指标赋权的合理性.最后以4个分指数作为变量,采用快速样本聚类法对我国31个省级行政区进行聚类分析.评价结果表明,2003年我国各生态环境指数存在显著的地域差异.自然条件从东南到西北呈明显的由优到劣的过渡趋势,降雨量、年均气温、森林覆盖率和水网密度4个指标是导致地域差异的主导因素;人类胁迫东部发达地区明显高于西部和中部地区,同一个地区经济发展水平存在显著的正相关;生态环境效应西北地区最为显著,同各地区自然条件存在显著的负相关,在人类活动干扰下,自然条件差的地区更容易发生生态损害与退化;社会响应无明显的地域分析规律,各地区经济发展水平对其有一定影响,但并非决定性因素.区域综合生态环境可持续性由区域NSI、HPI、EEI和SRI共同决定,综合评价得到2003年我国各省级行政区生态环境可持续性排序情况,其中生态环境可持续性最强的几个地区为海南、云南、广西、江西等地,最弱的几个地区为内蒙古、宁夏、上海、西藏、新疆等地.最后,聚类分析把我国31个省级行政区聚为生态环境特点各异的六大类,可以促进我国生态环境的分类管理.     

A lubricant boundary condition for a biological body lined by a thin heterogeneous biofilm

We study the asymptotic behavior of an incompressible viscous fluid flow in a biological body lined by a thin biological film with a cellular microstructure,varying thickness,and a heterogeneous viscosity regulated by a time random process.Let ting the thickness of the film tend to zero,we derive an effective biological slip boundary condition on the boundary of the body.This law relates the tangential fluxes to the tangential velocities via a proportional coefficient corresponding to the energy of some local problem.This law describes the ability of the biological film to function as a lubricant reducing friction at the wall of the body.The tangential velocities are functions of the random trajectories of a finely concentrated biological particle.     

猛犸雪原

正我对东北的了解和向往,最早来自上世纪70年代初期读过的描写北大荒知青生活的小说《征途》。我最感兴趣的是书中描述的东北的自然风光和动物植物:"遮天蔽日的红松林,尽管被大雪覆盖,但远远望去,依然是郁郁苍苍。朔风吹过,发出万马奔腾的松涛声。那一望无际的桦树林,好像千百株银枝玉树,俊秀挺拔地屹立在冰天雪地中";"咱这疙瘩呀,是‘棒打獐子瓢舀鱼,雉鸡飞到饭锅里’。汽车在公路上撞死几个挡道的狍子,跟你们南方碾死一条蛇一样不稀     

我国近代发酵工业的先驱——金培松

金培松(又名金柏卿,英文名Pei-sung King)1906年10月30日生于浙江省东阳后岑山村.童年时他是在农村渡过,牛角挂书,放牛识字.1919年进入东阳县长山小学,1923年高小毕业,入东阳县城初级中学,3年后毕业,考入浙江省立第一中学高中部,1年后因家庭经济困难辍学,1927年9月以高中肄业学历被上海劳动大学农学院农艺化学系录取,1931年毕业.     

Species Account of Anura ns from the Western Slope of Mt. Kita nglad,Mindanao Island,Philippines

The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species from high-elevation forests, in three sites of the western slope of Mt. Kitanglad range. The combined belt-transect sampling and microha bitat searches accounted for 13 species representing five families. The most represented family was Rhacophoridae with five representative species of the genus Philautus. Twelve out of the 13 species documented in the current survey are endemic. Four previously unaccounted species(Pelophr yne brevipes, Pulchrana grandocula, Sanguirana mearnsi, and Philautus surrufus) were added and brought the total anurans known from Mt. Kitanglad to 26 species. Most of the species were also recorded in forested sites, suggestive of their lesser affinity to non-forested ecosystems. The additional species detected during our survey may also imply that full understanding of anuran diversity of Mt. Kitanglad remains far from complete.     

2008年春鄱阳湖区斑背大尾莺状况

2008年1月下旬至2月上旬在中国南方广大地区发生冻雨雪灾害,给在鄱阳湖区越冬的斑背大尾莺(Locustella pryeri)带来不利影响,据3月上旬的调查,原本在江西鄱阳湖南矶湿地国家级自然保护区内广泛分布的斑背大尾莺已变得十分稀少.     

宁夏回族自治区六盘山国家级自然保护区发现毛冠鹿

2016年1月、8月和9月,在宁夏回族自治区固原市六盘山国家级自然保护区的两个林场(35°27′~35°38′N,106°12′~106°18′E,海拔2 202~2 221 m),利用红外相机拍摄到8张毛冠鹿(Elaphodus cephalophus)的有效照片。资料记载,该物种主要分布在中国的亚热带地区和缅甸的东北部,此次在宁夏回族自治区首次发现,为该区哺乳动物分布的新纪录。     

缺齿藓(真藓科)的形态特征和地理新分布

通过对内蒙古自治区与宁夏回族自治区交界处——贺兰山苔藓植物的调查采集和室内鉴定,发现了缺齿藓(Mielichhoferia mielichhoferiana)的一个新的地理分布记录。该文讨论了缺齿藓的形态特征和地理分布,将其与喜马拉雅缺齿藓、日本缺齿藓和中华缺齿藓进行了比较分析,并提供了该种的图版和中国缺齿藓属的分种检索表。该种的发现不仅丰富了中国缺齿藓属的研究资料,同时也说明了贺兰山的植物区系成分与喜马拉雅成分具有一定的关联。     

甘肃仓鼠的分类地位

自1928年Allen发表采自甘肃卓尼的甘肃仓鼠(Cansumys canus)以来,对其分类地位的争论就没有停止,不同学者从形态学和生态学方面研究得出了不同的结论。为了确认Allen所命名的甘肃仓鼠的分类地位,本研究利用形态性状和遗传性状,比较研究了甘肃、宁夏标本(包括模式产地标本)与华北、东北大仓鼠标本共计169只。结果显示:甘肃、宁夏地区标本身体及头骨量度与大仓鼠指名亚种、东北亚种间大多无显著性差异;地理分布连续,其间无隔离,也无地理重叠;生态特征与华北、东北的大仓鼠相似;基于线粒体DNA D-loop区序列的遗传变异分析表明,甘肃、宁夏地区种群与大仓鼠东北亚种种群关系较大仓鼠东北亚种种群与指名亚种种群关系更近;单倍型演化关系显示,指名亚种种群和东北亚种种群分别独立地由甘肃种群单倍型衍生而来,并且三个种群单倍型之间的分歧较浅,没有形成种上的分歧程度。据此,甘肃、宁夏地区“甘肃仓鼠”应为大仓鼠甘肃亚种[Cricetulus triton canus(Allen),1928]。     

基于生态系统服务的宁夏回族自治区自然-社会经济协调性分析

近年来,受全球气候变化和人类活动的双重影响,我国干旱半干旱区生态环境保护和社会经济发展面临着严峻挑战。生态系统服务是链接自然生态系统和人类福祉的桥梁,其持续供给对区域可持续发展具有重要意义。在具有生态重要性、脆弱性的地区,如何协调生态保护与社会经济发展的关系以达到可持续发展是重要的科学问题。以宁夏回族自治区为例,基于InVEST模型及相关地理图件,分析研究区生态系统服务变化及其权衡关系,通过耦合协调度模型分析生态系统服务与社会各项经济指标的耦合关系及空间差异,辨析区域耦合协调度的主要影响因素。结果表明：（1）研究区生态系统服务空间分异明显,土壤保持、水质净化、水资源供给和碳储存均呈现南高北低的特征。（2）县域尺度上各项生态系统服务之间显著正相关,呈现为协同关系;其中水质净化与水资源供给的相关性最高（相关系数是0.73）,其次是碳储量和水资源供给（相关系数是0.60）;而土壤保持与水质净化、水资源供给的相关性较低（相关系数均在0.50以下）。（3）宁夏回族自治区耦合协调度与城镇人口比重、城镇居民人均可支配收入负相关,与农村常住居民人均可支配收入正相关;产业分配模式与耦合协调度显著相关。（4）宁夏回族自治区约50%的县（区）处于勉强协调发展状态,其中73%的县（区）更注重经济发展;约41%的县（区）属于协调发展类,其中2/3的县区环境保护相对超前;中部地区的发展优势较强。研究结果对于准确把握经济社会发展过程中生态系统服务特征具有重要理论和实践意义,为促进宁夏生态保护与经济发展的统一协调提供科学辅助依据。     

宁夏水洞沟遗址第7地点石制品的剥片与修理技术

水洞沟遗址是中国较早发现并且最早发掘的旧石器遗址,该遗址自1923年发现以来便因其出土较多具有欧洲旧石器时代中晚过渡期特征的石制品而受到国内外学者的广泛关注。本文以水洞沟遗址第7地点（SDG7）出土的石制品材料为基础,主要从石核剥片策略和工具修理策略两个方面进行石器技术的分析研究。石核、石片以及工具的分析显示,SDG7存在两大石器技术体系：一是中国北方常见的占主导地位的石片石器技术,该技术不存在剥片前对石核的预制过程,而是以简单剥片石核、大量的不规则石片以及修理程度较低的工具为代表,少量采用优质原料精致加工的工具类型体现出旧石器时代晚期该技术的发展和进步;二是Levallois-like石叶技术,以少量的Levallois-like石核（扁脸石核）为代表,与SDG1、SDG2（CL5a）以及SDG9出土的同类石核呈现技术理念的一致性,该技术以剥离较大尺寸的石叶/长石片为目的,且均具有台面的预制修理和剥片面的维护现象,应为外来的技术体系。SDG7石器技术的分析可为水洞沟遗址区技术演化序列的构建、整体文化面貌的揭示以及技术变化原因的探讨提供新的材料和参考。     

宁夏六盘伪黑盲蛛记述(盲蛛目,开气门亚目,硬体盲蛛科)(英文)

记述了分布于中国宁夏回族自治区的伪黑盲蛛属Pseudomelanopa 1新种:六盘伪黑盲蛛P.liupan sp.nov.,此种与本属中的唯一种类台湾伪黑盲蛛P.taiwana相比较,雄蛛的阳茎和雌蛛的纳精囊明显不同;新种步足上的刺明显小于台湾伪黑盲蛛P.taiwana;新种雌蛛眼丘光滑,而台湾伪黑盲蛛P.taiwana眼丘上具1对小钝突;新种雄蛛触肢膝节和胫节光滑,仅在其膝节远端具1尖刺,而台湾伪黑盲蛛P.taiwana雄蛛触肢膝节和胫节背面具小齿.新种模式标本保存于河北大学博物馆.     

宁夏回族自治区纺蚋亚属鹿蚋组一新种记述(双翅目,蚋科)

记述蚋属Simulium纺蚋亚属Nevermannia鹿蚋组ruficorne group 1新种,该组的鉴别特征是雄性生殖腹板具中龙骨突,此乃该组首次以我国为模式产地的新种,标本采自宁夏回族自治区,以模式产地命名。其主要特征是幼虫上颚具附点,蛹茧具长背中突,雄虫生殖腹板蝶形,据上述综合特征可与该组已知其它近缘种相区别。     

宁夏中气门螨调查报告（蜱螨亚纲）（2）

本文是《宁夏中气门螨调查报告》第2报。文中记载中气门螨10科42种,其中宁夏新记录8种。     

中国宁夏下盾螨属一新种及轻绘下盾螨形态补充描述(蜱螨亚纲,厉螨科)

描述宁夏下盾螨属Hypoaspis Canestrini,1885 1新种,郭氏下盾螨Hypoaspis(Cosmolaelaps)guoi sp.nov.及轻绘下盾螨Hypoaspis(Cosmolaelaps)subpictus Guet Bai,1992的形态补充,标本均采自宁夏海原县红羊地区蚂蚁Myrmos sp.巢穴中,保存于军事医学科学院微生物流行病研究所医学昆虫标本馆。     

下盾螨属一新亚种和龚氏钝革螨后若虫形态描述(蜱螨亚纲,厉螨科,寄螨科)

记述下盾螨属 Hypoaspis Canestrini,1885的1新亚种,柔弱下盾螨宁夏亚种Hypoaspis debilis ningxiaensis Bai,ssp. nov.和龚氏钝革螨 Amblygamasus gongzhengdai Bai,2010后若螨形态,标本分别采自银川市南郊地表柳叶腐植层及银川花卉市场的高山榕盆景土壤表层。模式标本保存于军事医学科学院微生物流行病研究所昆虫标本馆和宁夏回族自治区疾病预防控制中心。