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11.
ERVĪNS LUKŠEVIČS PER E. AHLBERG ĢIRTS STINKULIS JEĻENA VASIĻKOVA IVARS ZUPIŅŠ 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(3):356-370
Luk?evi?s, E., Ahlberg, P.E., Stinkulis, ?., Vasi?kova, J. & Zupi??, I. 2011: Frasnian vertebrate taphonomy and sedimentology of macrofossil concentrations from the Langsēde Cliff, Latvia. Lethaia, Vol. 45, pp. 356–370. The siliciclastic sequence of the Upper Devonian of Kurzeme, Western Latvia, is renowned for abundant vertebrate fossils, including the stem tetrapods Obruchevichthys gracilis and Ventastega curonica. During the first detailed taphonomic study of the vertebrate assemblage from the Ogre Formation cropping out at the Langsēde Cliff, Imula River, abundant vertebrate remains have been examined and identified as belonging to one psammosteid, two acanthodian and three sarcopterygian genera; the placoderm Bothriolepis maxima dominates the assemblage. Besides fully disarticulated placoderm and psammosteid plates, separate sarcopterygian scales and teeth, and acanthodian spines, partly articulated specimens including complete distal segments of Bothriolepis pectoral fins, Bothriolepis head shields and sarcopterygian lower jaws have been found. The size distribution of the placoderm bones demonstrates that the individuals within the assemblage are of approximately uniform age. Distinct zones have been traced within the horizontal distribution of the bones. These linear zones are almost perpendicular to the dominant dip azimuth of the cross‐beds and ripple‐laminae and most probably correspond to the depressions between subaqueous dunes. Concavity ratio varies significantly within the excavation area. The degree of fragmentation of the bones and disarticulation of the skeletons suggest that the carcasses were reworked and slightly transported before burial. Sedimentological data suggest deposition in a shallow marine environment under the influence of rapid currents. The fossiliferous bed consists of a basal bone conglomerate covered by a cross‐stratified sandstone with mud drapes, which is in turn overlain by ripple laminated sandstone, indicating the bones were buried by the gradual infilling of a tidal channel. All the Middle–Upper Devonian vertebrate bone‐beds from Latvia are associated with sandy to clayey deposits and have been formed in a sea‐coastal zone during rapid sedimentation episodes, but differ in fossil abundance and degree of preservation. □Agnathans, Devonian, facies analysis, fish, fossil assemblage, palaeoenvironment. 相似文献
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Thomas G Kristensen Jesper Nielsen Christian NS Pedersen 《Algorithms for molecular biology : AMB》2010,5(1):9
Background
The fingerprint of a molecule is a bitstring based on its structure, constructed such that structurally similar molecules will have similar fingerprints. Molecular fingerprints can be used in an initial phase of drug development for identifying novel drug candidates by screening large databases for molecules with fingerprints similar to a query fingerprint. 相似文献13.
Thomas Mailund Gerth S Brodal Rolf Fagerberg Christian NS Pedersen Derek Phillips 《BMC bioinformatics》2006,7(1):29-8
Background
The neighbor-joining method by Saitou and Nei is a widely used method for constructing phylogenetic trees. The formulation of the method gives rise to a canonical Θ(n 3) algorithm upon which all existing implementations are based. 相似文献14.
Pomelova VG Bychenkova TA Grigor'eva AM Masalova OV Zubkov VV Barinskiĭ IF L'vov ND Kushch AA Ivanova LA Kudashov NI Osin NS Khramov EN 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(5):113-117
On the basis of the lanthanide immunofluorescent assay (LIFA) test systems for the determination of herpes simplex virus (HSV-LIFA) and cytomegalovirus (CMV-LIFA) antigens have been developed. The test system HSV-LIFA includes the sandwich of monoclonal antibodies (McAb) HSV A.3.3. or B-11 to type 2 HSV, strain BH; the test system CMV-LIFA includes the sandwich of rabbit McAb to CMV, strain AD 169. The approbation of the test systems has revealed that they insure the specific detection of HSV and CMV antigens in clinical specimens (urine, blood, liquor, saliva), the LIFA results well correlating with the data on the isolation of viruses in cell cultures, with the results obtained by other diagnostic methods and with clinical manifestations of diseases. LIFA has been shown to be more sensitive than the enzyme immunoassay. 相似文献
15.
Kharitonenkov IG Pomelova VG Bucher DJ Cozzolino A Bichenkova TA Sadykbekova RK Osin NS 《Biochemistry. Biokhimii?a》2002,67(6):640-650
A panel of fourteen different monoclonal antibodies was used for detection and analysis of antigenic determinants located on the outer surface protein A (OspA) of the spirochete Borrelia burgdorferi, which is a causative agent of tick-borne borreliosis (Lyme disease). Two main and several minor partially overlapping antigenic determinants have been found on the surface of the OspA protein of Borrelia burgdorferi sensu stricto (strain 297) by lanthanide competition fluoroimmunoassay. One of the main antigenic determinants is located in the N- and the other in the C-half of the OspA molecule. The involvement of the OspA protein in intact Borrelia burgdorferi sensu stricto (four bacterial strains have been analyzed: 297, B31, FR90-594, and CA90-742) is associated with retention of the above-mentioned two major antigenic determinants, but unlike the case of the isolated OspA they are partially overlapping with each other and with other antigenic determinants. The protein of the spirochete Borrelia afzelii (two bacterial strains have been analyzed: Ip-21 and Pko) contains only one antigenic determinant, which is the same as the main determinant of the OspA protein of Borrelia burgdorferi sensu stricto located in the N-half of the OspA molecule. 相似文献
16.
Anna Sircova Fariba Karimi Evgeny N. Osin Sungmin Lee Petter Holme Daniel Str?mbom 《PloS one》2015,10(3)
In a situation with a limited common resource, cooperation between individuals sharing the resource is essential. However, people often act upon self-interest in irrational ways that threaten the long-term survival of the whole group. A lack of sustainable or environmentally responsible behavior is often observed. In this study, we examine how the maximization of benefits principle works in a wider social interactive context of personality preferences in order to gain a more realistic insight into the evolution of cooperation. We used time perspective (TP), a concept reflecting individual differences in orientation towards past, present, or future, and relevant for making sustainable choices. We developed a personality-driven agent-based model that explores the role of personality in the outcomes of social dilemmas and includes multiple facets of diversity: (1) The agents have different behavior strategies: individual differences derived by applying cluster analysis to survey data from 22 countries (N = 10,940) and resulting in 7 cross-cultural profiles of TP; (2) The non-uniform distribution of the types of agents across countries; (3) The diverse interactions between the agents; and (4) diverse responses to those interactions in a well-mixed population. As one of the results, we introduced an index of overall cooperation for each of the 22 countries, which was validated against cultural, economic, and sustainability indicators (HDI, dimensions of national culture, and Environment Performance Index). It was associated with higher human development, higher individualism, lower power distance, and better environmental performance. The findings illustrate how individual differences in TP can be simulated to predict the ways people in different countries solve the personal vs. common gain dilemma in the global limited-resource situation. This interdisciplinary approach to social simulation can be adopted to explain the possible causes of global environmental issues and to predict their possible outcomes. 相似文献
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18.
Thomas?MailundEmail author Mikkel?H?Schierup Christian?NS?Pedersen Peter?JM?Mechlenborg Jesper?N?Madsen Leif?Schauser 《BMC bioinformatics》2005,6(1):252
Background
Coalescent simulations are playing a large role in interpreting large scale intra-specific sequence or polymorphism surveys and for planning and evaluating association studies. Coalescent simulations of data sets under different models can be compared to the actual data to test the importance of different evolutionary factors and thus get insight into these. 相似文献19.
Genetic organization of 52 Vibrio cholerae El Tor biotype preseventh and seventh pandemic strains isolated in various periods was studied by PCR assay and DNA-DNA hybridization. It was established that the genome of most ancient of analyzed strains isolated from a diarrhea patient in 1910 was devoid of CTX and RS1 prophages, vibrio pathogenicity islands (VPI and VPI-2), and pandemic islands (VSP-1 and VSP-2) that contain key virulence genes. The appearance of pathogenic properties in cholera vibrios for the first time causing a local outbreak of cholera in 1937 is connected with the acquisition of VPI and CTX that carried genes tcpA and ctx-AB, respectively, which are responsible for the colonization of small intestine and encode the production of cholera toxin. The appearance of seventh pandemic agent for cholera was shown to correlate with the acquisition by its precursor of two additional blocks of genes VSP-1 and VSP-2. This finding strongly supports the involvement of these genes in formation of the pandemic potential in strains. Molecular typing methods allowed elucidation of differences in the genetic organization between prepandemic and pandemic strains. The detected variability of the genome of contemporary virulent strains may be a reason for the occurrence of etiological agent for cholera with new properties. 相似文献
20.
Lisa NS Shama Karen B Kubow Jukka Jokela Christopher T Robinson 《BMC evolutionary biology》2011,11(1):1-11