山西垣曲曙猿化石的发现

山西垣曲曙猿化石的发现黄学诗山西垣曲寨里土桥沟曙猿化石的发现,在国际上引起很大反响,因为它关系到包括我们人类在内的高等灵长类的祖先究竟是什么样的动物、它最早起源在地球上那一块地方的学术界研究的热门课题。山西垣曲盆地是中条山脉中一个小型的山间盆地,也是...     

犀貘(哺乳纲,奇蹄目,貘超科)化石在垣曲盆地的发现

记述了在山西省垣曲盆地发现的犀貘一新种———童氏犀貘 (Hyrachyustongisp .nov .)。它的发现揭示了在垣曲盆地有中中始新世地层存在的可能性。还对以往在中国境内发现的犀貘化石做了简要评述     

Using the inverse Poisson distribution to calculate multiplicity of infection and viral replication by a high-throughput fluorescent imaging system

正Dear Editor,For virologists,it is crucial to confidently determine the concentration of infectious particles that are utilized and produced in experiments(Dulbecco,1952;Bushar and Sagripanti,1990;La Barre and Lowy,2001;Gueret et al.,2002;Gao et al.,2009;Kutner et al.,2009;Grigorov et al.,2011;Knipe and Howley,2013).With respect to     

Resolving the Activation Site of PositiveRegulators in Plant PhosphoenolpyruvateCarboxylase

Dear Editor, Phosphoenolpyruvate carboxylase （PEPC; EC 4.1.1.31） islocated at an important branch point in the carbohydratemetabolism of plants. The enzyme is a homotetramer andcatalyzes the addition of bicarbonate to phosphoenolpyru-vate （PEP） to form oxaloacetate and phosphate. PEPC isregulated by metabolites and phosphorylation. AIIostericfeedback inhibition is mainly regulated by L-malate andL-aspartate which bind to a site separated from the activecenter （Kai et al., 1999; Paulus et al., 2013）. Structure analy-sis of PEPC from Escherichia coli （Kai et al., 1999; Matsumuraet al., 2002）, Zea rnays （Matsumura et al., 2002）, Flaveria trin-ervia, and F. pringlei （Paulus et al., 2013） revealed that thesubstrate PEP and the feedback inhibitors bind to separatesites within each monomer.     

In vivo tunable CRISPR mediates efficient somatic mutagenesis to generate tumor models

Dear Editor, CRISPR/Cas9 has revolutionized genome editing technology due to its simplicity and robustness (Mali et al., 2013). Several inducible CRISPR/Cas9 systems recently developed make spatiotemporal genome editing possible (Kon ermann et al., 2013;Balboa et al., 2015;Dow et al., 2015;Zetsche et al., 2015;Liu et al., 2016;Kleinjan et al., 2017;Maji et al.. 2017;Senturk et al., 2017;Lu et al., 2018).     

MIT1, encoding a 15-cis-ζ-carotene isomerase,regulates tiller number and stature in rice

正Lateral branching is an important determinant of shoot architecture and crop yield. The plant hormone strigolactone (SL) inhibits lateral bud outgrowth in various plant species. Deficiencies in SL biosynthesis and signal transduction result in excessive outgrowth of lateral buds (Stirnberg et al., 2002; Sorefan et al., 2003).     

垣曲盆地中始新世貘类和犀类新材料

记述了近年来在山西垣曲盆地中始新世河堤组任村段中发现的貘类和犀类化石计４科７属８种动物。它们不仅为原有类群增加了新材料,而且出现了该地区以前不曾有过的种类,因而丰富了垣曲盆地中始新世哺乳动物群内涵。     

Import of Rift Valley fever to China: a potential new threat?

正Several recent studies in Virologica Sinica and other journals have highlighted the enormous international challenge of emerging arboviral diseases,such as Zika virus disease,dengue,and chikungunya(Islam et al.,2015;Maurice et al.,2015;Dai et al.,2016;Deng et al.,2016;Song et al.,2016;Wang et al.,2016;Xu et al.,2016;Zhang et al.,2016;Zhou et     

Structural basis of AimP signaling molecule recognition by AimR in Spbeta group of bacteriophages

Dear Editor,Quorum sensing(QS)is a widespread phenomenon in bacteria which enables them to participate in cell-to-cell communication by producing and responding to small signal molecules,thus synchronously altering their behavior depending on population density(Singh et al.,2000;Miller and Bassler,2001).Through QS,bacteria coordinate processes such as expression of virulenee factors(Slamti and Lereclus,2002),biofilm formation(Parashar et al.,2011),sporulation(Perego et al.,1996),conjugation(Kozlowicz et al.,2006),antibiotic synthesis(Miller and Bassler,2001;Whiteley et al.,2017)etc.     

中美科学家野外考察散记

中美科学家野外考察散记黄学诗１９９４年５月,中国科学院古脊椎动物与古人类研究所科学工作者一行７人,与美国得克萨斯大学和卡奈基博物馆６名专家,对山西省垣曲盆地地质和古生物作了为期２０天的抢救性的考察。垣曲盆地是中条山脉许多山间盆地中的一个小型盆地,在行...     

Phenotypic plasticity of Vaccinium meridionale (Ericaceae) in wild populations of mountain forests in Colombia

Vaccinium meridionale is a promising crop for the Andean region of South America and is currently available only in the wild. Spontaneous populations of this plant are found across the Colombian mountains, but very few published records on this plant morphology are available. A zonification study of V. meridionale was conducted in four principal areas of a low mountain forest of Colombia (Provinces of Boyacá, Cundinamarca, Santander and Nari?o) in 2007. A total of 20 populations and 100 plants of V. meridionale were individually characterized and surveyed, using a list of 26 characters of morphological variables (9 quantitative and 17 qualitative characters). Our results indicated that natural populations of V. meridionale might be found in the tropical forest under a highly heterogeneous climate and microclimate conditions, at different mountain regions between 2 357 and 3 168masl. The shrubs of V. meridionale exhibited a high level of intra-population variation in several quantitative (plant height, stem diameter) and qualitative (growth habit, ramification density, presence of anthocyanins in stems) morphological characters, suggesting an environmentally induced phenotypic plasticity. Plant height, stem diameter and foliar density were the most variable morphological traits, with coefficients of variation higher than 50%. However, several quantitative characters of its reproductive potential, such as berry dimensions, rachis length and number of flowers per inflorescence, resulted with low plasticity with coefficients of variation lower than 30.2%, indicating that these characters were genetically determined. The highest correlation coefficients (p < 0.05) resulted to be between fruit length and fruit width (0.90), leaf length and leaf width (0.78), plant height and stem diameter (0.60), and inflorescence length and flowers number per inflorescence (0.57). The results suggest that an important genetic resource exists for this species in the wild. Low variation in fruit size, which constitutes a target trait for plant breeders, could be useful for selection of cultivars of V. meridionale. The results of this study could also be applied in conservation programs aimed to protect these diverse populations in the mountain forests of Colombia.     

Apomorphic and plesiomorphic ITS-1 rDNA patterns in morphologically similar snails (Stylommatophora: Vallonia), with estimates of divergence time

Morphological classification of snail shells is sometimes arbitrary and misleading in correct species delimitation. This topic is investigated in four nominal species of the minute gastropods of the genus Vallonia ( V. pulchella , V. excentrica , V. costata and V. enniensis ). First, individuals are classified according to their shell morphology. Second, variation in ribosomal internal transcribed spacer 1 DNA (ITS-1 rDNA) is analysed. Using a cladistic approach, the nucleotide positions of the ITS-1 are elucidated on apomorphic and plesiomorphic character states (outgroup= Acanthinula aculeata ; Valloniidae). The molecular data yield evidence that the morphospecies V. excentrica is a paraphyletic group, comprising just a loose arrangement of individuals with similar shells. Data on fossil shells and putative divergence time are also elucidated. In the monograph on Vallonia it has been suggested that the split between the branch of V. costata and the branch of V. pulchella , V. excentrica and V. enniensis could have been in the upper Cretaceous. Based on the ITS-1 sequence alignment and the number of variable nucleotide positions, it is suggested that the last common ancestor of both branches lived at some time during the Miocene or even the Pliocene. Therefore, the fossil stem lines of Vallonia should be newly interpreted.     

Faunal correlation of Wadi Moghara, Egypt: implications for the age of Prohylobates tandyi

Wadi Moghara, Egypt, is an early Miocene fossil locality with a mammalian fauna that includes Prohylobates tandyi, one of the earliest known representatives of the Cercopithecoidea. Faunal correlations were conducted between Moghara, Gebel Zelten (Libya) and a series of East African fossil sites with established radiometric dates in order to estimate the age of the Moghara mammals, including P. tandyi. Results confirm hypotheses proposed in some previous studies that: (1) Moghara is about 18-17 Ma, approximately the same age as the Hiwegi fauna from Rusinga Island (Kenya); (2) Moghara is slightly older than Gebel Zelten (Libya) (17-15 Ma); and (3) the cercopithecoid tooth presently identified as Victoriapithecus sp. from Napak V (ca. 19 Ma) is currently the oldest known record of a fossil Old World monkey, followed by P. tandyi from Moghara (Egypt) (18-17 Ma) and Prohylobates sp. from Buluk (Kenya) (>17.2 Ma), P. simonsi from Gebel Zelten (Libya) (ca. 17-15 Ma), and V. macinnesi from Maboko (Kenya) (ca. 16-14.7 Ma).     

河南淅川早始新世一新原鸟

河南淅川这一新原鸟类化石,根据如下特征:胫跗骨外关节髁的外边缘超过胫跗骨的外边缘、内外两髁间成一“V”字形沟、内关节髁的内面具一近似“T”字形隆凸,骨质腱桥上边缘外斜、下边缘内斜,腱桥靠近胫跗骨内缘等,订一新属种:淅川中原鸟。中原鸟的时代为早始新世,它代表到目前为止我国时代最早和巨型鸟类——不飞鸟目的唯一材料。     

Trace fossil associations related to facies of an upper Ordovician low wave energy shoreface and shelf, Oslo-Asker district, Norway

Three trace fossil associations have been identified from facies interpreted as low wave energy upper, middle and lower shoreface deposits, transitional shoreface/shelf deposits and open epicontinental shelf deposits. These were developed in pre-regressive, regressive and transgressive phases associated with eustatic sea level changes caused by the upper Ordovician glaciation. The three associations are the Skolithos-Diplocraterion association, the Diplichnites-Phycodes association and the Thalassinoides association. The Skolithos-Diplocraterion association inhabited upper, middle and lower shoreface environments, the Diplichnites-Phycodes association a lowermost shoreface environment and the Thalassinoides association inhabited offshore epicontinental shelf environmcnts. The Skolithos-Diplocraferion and Diplichnites-Phycodes associations bear strong affinities with previously described Skolithos ichnofacies assemblages (indicating shoreline environments) and the Cruziana ichnofacies forms (indicating shallow water environments down to wave base) respectively. The Thalassinoides assemblage, however, closely compares with assemblages described from Mesozoic epicontinental shelf sequences. Trace fossil diversity achieves a maximum in the lowermost shoreface environment and reduces in deeper water and shallower water environments. This accords with diversity patterns identified in analogous Jurassic epicontinental palaeonvironments. The stratigraphic distribution of some trace fossil association boundaries accords with those of contemporary body fossil associations. However, several body fossil associations are included within the volume of distribution of a single trace fossil assemblage. □ Trace fossil association, shoreface and shelf, Oslo district, upper Ordovician.     

New fossil materials of the earliest new world monkey, Branisella boliviana, and the problem of platyrrhine origins

Branisella boliviana, from the Late Oligocene of Salla, Bolivia, is the oldest fossil platyrrhine monkey discovered. To date, several fossil specimens of Branisella have been obtained, but most of them are fragmentary dentitions, so the animals craniodental morphology is still obscure. During the 1996 field season a pair of upper and lower jaw fragments and another nearly complete mandible were recovered. These new fossil materials reveal the following morphological features in Branisella: 1) P(2) is much smaller than P(3,4), whereas P(2) is relatively small but probably sexually dimorphic; 2) the zygomatic arch protrudes smoothly posterolaterally from the maxillary bone, as in extant Callicebus; 3) the mandibular arcade is nearly V-shaped and the symphysial angle, which is formed by the horizontal plane and the anterior face of mandibular symphysis, is about 40 degrees, i.e., it neither leans as far anteriorly as in callitrichines nor does it stand as vertically as Cebus; 4) upper and lower molars wore down rapidly in life, suggesting a herbivorous diet and the possibility of terrestriality; and 5) dental eruptive sequence is the same as in extant Aotus. As a whole, the dentition of Branisella is very similar to that of Proteopithecus from the Late Eocene of Fayum, Egypt, except in the lower canine morphology, suggesting a close phyletic relationship between them. The origin and early diversification of platyrrhine monkeys might have occurred on the African continent before crossing the Atlantic Ocean.     

Cranial nerves in the Australian lungfish,Neoceratodus forsteri,and in fossil relatives (Osteichthyes: Dipnoi)

Three systems, two sensory and one protective, are present in the skin of the living Australian lungfish, Neoceratodus forsteri, and in fossil lungfish, and the arrangement and innervation of the sense organs is peculiar to lungfish. Peripheral branches of nerves that innervate the sense organs are slender and unprotected, and form before any skeletal structures appear. When the olfactory capsule develops, it traps some of the anterior branches of cranial nerve V, which emerged from the chondrocranium from the lateral sphenotic foramen. Cranial nerve I innervates the olfactory organ enclosed within the olfactory capsule and cranial nerve II innervates the eye. Cranial nerve V innervates the sense organs of the snout and upper lip, and, in conjunction with nerve IX and X, the sense organs of the posterior and lateral head. Cranial nerve VII is primarily a motor nerve, and a single branch innervates sense organs in the mandible. There are no connections between nerves V and VII, although both emerge from the brain close to each other. The third associated system consists of lymphatic vessels covered by an extracellular matrix of collagen, mineralised as tubules in fossils. Innervation of the sensory organs is separate from the lymphatic system and from the tubule system of fossil lungfish.     

New Pliocene remains of Camelus grattardi (Mammalia,Camelidae) from the Shungura Formation,Lower Omo Valley,Ethiopia, and the evolution of African camels

Abstract

Camels are exceptionally rare in the Plio-Pleistocene fossil record of Africa, hindering attempts to understand the evolution of this family on the continent. Here we describe recently collected camel specimens from the Shungura Formation, Lower Omo Valley, Ethiopia, and attribute these remains to Camelus grattardi. The new specimens date to the late Pliocene (~3 to 2.6 Ma) and consist of three upper molars, one upper premolar, and two proximal metatarsals. The dental specimens confirm this species’ small P4 relative to its molars, a trait that differs significantly from all extant and fossil Old World camels. The metatarsals indicate that C. grattardi was similar in size to the living Bactrian camel, C. bactrianus. Phylogenetically, we find no suitable ancestor, sister, or descendant of the eastern African fossil camel, which suggests greater lineage diversity in Plio-Pleistocene Camelus than previously recognised. Microwear analyses suggest that C. grattardi was likely a mixed-feeder preferring browse, which is consistent with carbon isotopes of enamel from the Turkana Basin. A review of the fossil record of African camels suggests no clear paleoenvironmental association, as fossil camels occur in a range of environments from dry savannas with no permanent water bodies to closed woodlands along the paleo-Omo River.     

关于董氏狼鳍鱼(Lycoptera tungi)的种上归类

本文重新研究了董氏狼鳍鱼 (Lycoptera tungi Liu et al 1963).将产自宁夏隆德石窑寺的董氏狼鳍鱼 V2323 号标本从狼鳍鱼属 (Lycoptera) 中分出来,归入华夏鱼属 (Huashia), 修定为董氏华夏鱼 (Huashia tungi (Liu et al.)).同时对华夏鱼科 (Huashiidae) 的系统位置作了初步讨论.     

Samaras of Ventilago (Rhamnaceae) from the upper Miocene of Lincang,Yunnan, China and their phytogeographic implications

The genus Ventilago Gaertn. usually occurs in hot, dry, and low-altitude tropical environments. The fossil record of this genus is meager, so its origin and geographic history are still poorly understood. We describe a fossil winged fruit species-Ventilago lincangensis K. N. Liu & S. P. Xie sp. nov. from the upper Miocene Bangmai Formation of Lincang city, Yunnan Province, China. The fossil conforms to the modern genus Ventilago in architecture of the prominent fruit wing including a prominent midvein, a set of minor longitudinally secondary veins extending the full length of the fruit and reticulate higher order venation. The elliptical fruit body at the base of the wing shows an equatorial rim and has a short pedicel. This is the first report of Ventilago fruits in China, and is significant for the investigation of the origin and evolutionary history of this genus.