林麝前肢骨骼解剖

运用大体解剖学方法对三头林麝前肢骨骼进行了研究，并与牛、羊和鹿类的前肢骨骼进行了比较。林麝前肢骨骼的主要特征是：肩胛骨短而宽、肩胛冈特别长，肩峰呈锐角，其末端与肩臼位于同一平面；肱骨近端外侧结节的前部特别发达；前臂骨明显向前弯，只有一个前臂骨间隙，尺骨体呈薄板状；第3和第4掌骨发达，第2和第5掌骨保留远侧部；第3和第4指发达，冠骨和蹄骨较长；第2和第5指较小，每指各有3个指节骨和2个近籽骨。     

A new mammaliaform from the early Jurassic and evolution of mammalian characteristics

A fossil from the Early Jurassic (Sinemurian, approximately 195 million years ago) represents a new lineage of mammaliaforms, the extinct groups more closely related to the living mammals than to nonmammaliaform cynodonts. It has an enlarged cranial cavity, but no postdentary trough on the mandible, indicating separation of the middle ear bones from the mandible. This extends the earliest record of these crucial mammalian features by some 45 million years and suggests that separation of the middle ear bones from the mandible and the expanded brain vault could be correlated. It shows that several key mammalian evolutionary innovations in the ear region, the temporomandibular joint, and the brain vault evolved incrementally through mammaliaform evolution and long before the differentiation of the living mammal groups. With an estimated body weight of only 2 grams, its coexistence with other larger mammaliaforms with similar "triconodont-like" teeth for insectivory within the same fauna suggests a great trophic diversity within the mammaliaform insectivore feeding guild, as inferred from the range of body sizes.     

Multilineage potential of adult human mesenchymal stem cells

Human mesenchymal stem cells are thought to be multipotent cells, which are present in adult marrow, that can replicate as undifferentiated cells and that have the potential to differentiate to lineages of mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma. Cells that have the characteristics of human mesenchymal stem cells were isolated from marrow aspirates of volunteer donors. These cells displayed a stable phenotype and remained as a monolayer in vitro. These adult stem cells could be induced to differentiate exclusively into the adipocytic, chondrocytic, or osteocytic lineages. Individual stem cells were identified that, when expanded to colonies, retained their multilineage potential.     

Amphibians as indicators of early tertiary "out-of-India" dispersal of vertebrates

Sixty-five million years ago, massive volcanism produced on the India-Seychelles landmass the largest continental lava deposit (Deccan Traps) of the past 200 million years. Using a molecular clock-independent approach for inferring dating information from molecular phylogenies, we show that multiple lineages of frogs survived Deccan Traps volcanism after millions of years of isolation on drifting India. The collision between the Indian and Eurasian plates was followed by wide dispersal of several of these lineages. This "out-of-India" scenario reveals a zoogeographical pattern that might reconcile paleontological and molecular data in other vertebrate groups.     

Capture Enhancement in a Carnivorous Aquatic Plant: Function of Antennae and Bristles in Utricularia vulgaris

Traps of the carnivorous hydrophyte Utricularia vulgaris Linnaeus (Lentibulariaceae) have structures termed antennae and bristles around their trapdoors that increase their rate of entrapment of the substrate-dwelling prey Chydorus sphaericus (Chydoridae, Crustacea). The kind and number of these structures are important in determining capture rate. Experimental data and corresponding behavioral observations support Darwin's hypothesis that antennae and bristles function as a "funnel" leading potential prey toward the trapdoor and their capture by offering the prey a favorable substrate that exploits their natural locomotor and feeding behavior.     

Matriarchs as repositories of social knowledge in African elephants

Despite widespread interest in the evolution of social intelligence, little is known about how wild animals acquire and store information about social companions or whether individuals possessing enhanced social knowledge derive biological fitness benefits. Using playback experiments on African elephants (Loxodonta africana), we demonstrated that the possession of enhanced discriminatory abilities by the oldest individual in a group can influence the social knowledge of the group as a whole. These superior abilities for social discrimination may result in higher per capita reproductive success for female groups led by older individuals. Our findings imply that the removal of older, more experienced individuals, which are often targets for hunters because of their large size, could have serious consequences for endangered populations of advanced social mammals such as elephants and whales.     

“书于竹帛”与图书馆萌芽

在遥远的历史长河中,人类创造和运用了符号系统,创造出记录语言的文字。同时,人类开始多方寻找文字符号赖以存在的有形载体：甲骨、青铜器、石头、简牍、缣帛……只有当文字符号找到了恰当的载体时,才形成＂书＂。于是,便有了图书馆。     

"十全大补"药渣对肥育猪生长、胴体特性和肉质的影响

研究在基础日粮中添加不同剂量"十全大补"药渣对肥育猪生长性能、胴体特性和肉质的影响.与对照组比较,肥育猪日粮中添加0.5%、1.0%、1.5%的中草药渣日增重分别增加7.40%(P＜0.05)、12.88%(P＜0.05)和9.75%(P＜0.05),料重比分别降低5.20%(P＜0.05)、7.23%(P＜0.05)和6.07%(P＜0.05);瘦肉率分别提高3.86%(P＞0.05)、6.27%(P＜0.05)和5.80%(P＜0.05),脂肪率分别降低6.42%(P＜0.05)、9.63%(P＜0.05)和9.30%(P＜0.05),背膘厚分别降低7.20%(P＜0.05)、13.26%(P＜0.05)和12.12%(P＜0.05),眼肌面积分别提高4.46%(P＞0.05)、9.24%(P＜0.05)和6.30%(P＜0.05);肌肉红色色度分别提高2.75%(P＞0.05)、6.67%(P＜0.05)和3.92%(P＞0.05),滴水损失率分别降低9.32%(P＜0.05)、12.42%(P＜0.05)和8.07%(P＜0.05);粗脂肪含量分别提高20.80%(P＜0.05)、28.47%(P＜0.01)和25.55%(P＜0.01).结果表明"十全大补"药渣可作为肥育猪饲料添加剂,具有改善其生长、胴体特性和肉质的效果.     

英语中“就”的表达形式

汉语中“就”字结构及意义非常丰富,本文仅从翻译学的角度分析汉语中的“就”与英语相对应的表达形式,以及“就”的习惯逻辑搭配在英语中的表现形式。     

Gene targeting in stem cells from individuals with osteogenesis imperfecta

Adult stem cells offer the potential to treat many diseases through a combination of ex vivo genetic manipulation and autologous transplantation. Mesenchymal stem cells (MSCs, also referred to as marrow stromal cells) are adult stem cells that can be isolated as proliferating, adherent cells from bones. MSCs can differentiate into multiple cell types present in several tissues, including bone, fat, cartilage, and muscle, making them ideal candidates for a variety of cell-based therapies. Here, we have used adeno-associated virus vectors to disrupt dominant-negative mutant COL1A1 collagen genes in MSCs from individuals with the brittle bone disorder osteogenesis imperfecta, demonstrating successful gene targeting in adult human stem cells.     

Effective enforcement in a conservation area

Wildlife within protected areas is under increasing threat from bushmeat and illegal trophy trades, and many argue that enforcement within protected areas is not sufficient to protect wildlife. We examined 50 years of records from Serengeti National Park in Tanzania and calculated the history of illegal harvest and enforcement by park authorities. We show that a precipitous decline in enforcement in 1977 resulted in a large increase in poaching and decline of many species. Conversely, expanded budgets and antipoaching patrols since the mid-1980s have greatly reduced poaching and allowed populations of buffalo, elephants, and rhinoceros to rebuild.     

Biogeological mineralization in deep-sea hydrothermal deposits

Oriented drill cores retrieved from active massive sulfide edifices at the Endeavour Segment of the Juan de Fuca Ridge contain an abundance of fossilized tube structures associated with vestimentiferan and annelid worms. The petrological evolution of these biogeological structures and their presence deep inside the edifice walls demonstrate that an initial, worm-mediated texture directly affects the subsequent steps of inorganic precipitation, wall infilling, and outward growth of these black smoker deposits. The presence of fossilized structures in hydrothermal discharge sites that are 2 kilometers apart and their similarity to structures observed in other modern and ancient deposits suggest that these biogeological processes are general phenomena.     

Comment on "On the regulation of populations of mammals, birds, fish, and insects" IV

Sibly et al.'s (Reports, 22 July 2005, p. 607) contention that density dependence acts strongly on low-density animal populations irrespective of body size contradicts many long-term studies of large mammals. Their findings were distorted by harvest records, which may poorly reflect population trend. Omitting unreliable data, their massive data set is reduced to only one case for large mammals.     

东疆沙蟒Eryx orentalis-xinjiangensis骨骼的解剖

本文论述了东疆沙蟒的骨骼系统.其鼻骨长与额骨以纤维结缔组织相连接。舌骨退化仅残留两条舌骨后角。腭罩以结缔组织及韧带悬挂在脑颅下,上颌骨齿每侧各10枚,翼骨齿各4枚(少数个体5枚),腭骨齿各4枚,下颌骨则各具12枚,均为端生齿。椎骨数为233～237枚,其中躯干椎201～211枚,尾椎26～36枚,尾椎骨椎体向后逐渐缩短,末端3枚愈合。后肢留痕迹器官,髂骨和股骨均为扁平薄片状,远端以韧带与爪状鳞相接。     

Adaptations for climbing in north american multituberculates (mammalia)

A recently discovered skeleton of Ptilodus exhibits several specializations for climbing. A survey of postcranial bones of Cretaceous and early Cenozoic multituberculates from North America reveals similar locomotor specializations. Multituberculates possessed distinctive tarsal adaptations for a range of pedal mobility characteristic of arboreal mammals that descend trees headfirst. The divergent hallux could move independently of the other digits. The long robust tail of Ptilodus possessed musculoskeletal features that, among living mammals, are associated with prehensility.     

Associativity of selected traits in Aginskaya semicoarse wool sheep

Research findings in the phenotypic correlations of the live weight to the body measurements and the body conformation indices in the replacement young stock of the semicoarse wool sheep of the Aginskaya breed have been reported. It is ascertained that males surpass the females in the live weight and the body measurements. The calculation of the conformation indices has shown that the rams compared to the ewes are more massive, more compact, and wider, while the ewes differ in leg length and elongation. A high positive correlation between the live weight and the chest girth is established both in males and females (r = 0.751; r = 0.688, respectively). In ram lambs, a high positive correlation between the live weight and the measurements characterizing the meat quality of sheep (the depth, width, and girth of the chest; the width between hip bones) has been revealed.     

Significance of "tethyan" fossils in the american cordillera

Equatorial faunas of the ancient Tethyan seaway, which extended from western Europe to southeastern Asia, comprise some of the most diverse marine taxa in the fossil record. Comparable or identical "Tethyan" species that occur far from the Tethyan seaway in Paleozoic and Mesozoic rocks of the North and South American Cordillera have long been considered as a major biogeographic anomaly. Two leading theories to account for the occurrence of these anomalous "Tethyan" faunas in the Cordillera are that they were transported long distances to the east on tectonic blocks(suspect terranes that originated near the Tethys) or that they migrated westward via undiscovered marine corridors through continental areas of Pangea. An alternative model is that these "Tethyan" fauna were pantropic species that extended with attenuated diversities into the eastern proto-Pacific Ocean. This pantropic model can better account for the distribution patterns of many Paleozoic and early Mesozoic "Tethyan" species in the American Cordillera and provides a steady state hypothesis against which the other models can be tested. The distribution of pre-Cretaceous "Tethyan" faunas is similar to the known pantropic distribution of many Cretaceous and Cenozoic tropical biotas. During the Cenozoic, taxa were most diverse in the Tethys and Indo-West Pacific regions but extended with attenuated diversity to many parts of the equatorial Pacific Ocean, including the west coasts of North and South America. The eastern Pacific occurrence of many Indo-West Pacific species provides a modern analog for the occurrence of many anomalous "Tethyan" fossils in the American Cordillera.     

从“营造生态”到“需求驱动”:学术图书馆如何满足人文学者的数字学术需求

[目的/意义]“营造生态”和“需求驱动”是学术图书馆满足人文学者的数字学术需求、构建数字人文服务体系的两个核心关键词。这两者要求我们从宏观的业态视角理解图书馆的数字人文服务策略,进而从学理层面探寻构建数字人文生态的可行路径。[方法/过程]文章基于课题组的前期积累和相关案例,探讨构建数字人文生态的必要性和可能性。[结果/结论]文章的主要结论包括：（1）强调要尊重客观规律和客观现实,将“数字人文生态”的构建视为数字人文工作首要目标;（2）提出要理清人文学者不同类型的数字学术需求,根据需求展开学术图书馆的类型学研究;（3）学术图书馆可以划分为引领型学术图书馆、支撑型学术图书馆和基础型学术图书馆,应当推动不同类型学术图书馆在数字学术生态中各司其职,对接人文学者不同的需求,在有差异化的服务和合作中构建数字人文生态。     

Chemically anomalous, preaccretionally irradiated grains in interplanetary dust from comets

Nonstoichiometric grains with depletions of magnesium and silicon (relative to oxygen) and inclusions of iron-nickel metal and iron-rich sulfides have been identified in interplanetary dust particles from comets. These chemical anomalies accumulate in grains exposed to ionizing radiation. The grains, known as GEMS (glass with embedded metal and sulfides), were irradiated before the accretion of comets, and their inferred exposure ages, submicrometer sizes, and "amorphous" silicate structures are consistent with those of interstellar silicate grains. The measured compositional trends suggest that chemical (as well as isotopic) anomalies can be used to identify presolar interstellar components in primitive meteoritic materials.     

“森林—竹子—大熊猫”非线性动力系统的周期解与混沌奇怪吸引子

为从理论上研究＂森林—竹子—大熊猫＂三位一体的保护栖息地理念,考虑了竹子开花的影响,把竹子和森林分成两个阶段,建立了一个描述＂森林—竹子—大熊猫＂的非线性动力系统。利用Mawhin重合度理论可以证明此系统存在一个周期解,利用计算机数值模拟画出了此动力系统的周期解随时间的变化规律和相图。数值模拟显示脉冲的影响非常复杂,进...