897 resultados para L22 - Firm Organization and Market Structure
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Kaposi's sarcoma-associated herpesvirus (KSHV) is a recently discovered DNA tumor virus that belongs to the gamma-herpesvirus subfamily. Though numerous studies on KSHV and other herpesviruses, in general, have revealed much about their multilayered organization and capsid structure, the herpesvirus capsid assembly and maturation pathway remains poorly understood. Structural variability or irregularity of the capsid internal scaffolding core and the lack of adequate tools to study such structures have presented major hurdles to earlier investigations employing more traditional cryo-electron microscopy (cryoEM) single particle reconstruction. In this study, we used cryo-electron tomography (cryoET) to obtain 3D reconstructions of individual KSHV capsids, allowing direct visualization of the capsid internal structures and systematic comparison of the scaffolding cores for the first time. We show that B-capsids are not a structurally homogenous group; rather, they represent an ensemble of "B-capsid-like" particles whose inner scaffolding is highly variable, possibly representing different intermediates existing during the KSHV capsid assembly and maturation. This information, taken together with previous observations, has allowed us to propose a detailed pathway of herpesvirus capsid assembly and maturation.
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A series of human-rodent somatic cell hybrids were investigated by Southern blot analysis for the presence or absence of twenty-six molecular markers and three isozyme loci from human chromosome 19. Based on the co-retention of these markers in the various independent hybrid clones containing portions of human chromosome 19 and on pulsed field mapping, chromosome 19 is divided into twenty ordered regions. The most likely marker order for the chromosome is: (LDLR, C3)-(cen-MANNB)-D19S7-PEPD-D19S9-GPI-TGF$ \beta$-(CYP2A, NCA, CGM2, BCKAD)-PSG1a-(D19S8, XRCC1)-(D19S19, ATP1A3)-(D19S37, APOC2)-CKMM-ERCC2-ERCC1-(D19S62, D19S51)-D19S6-D19S50-D19S22-(CGB, FTL)-qter.^ The region of 19q between the proximal marker D19S7 and the distal gene coding for the beta subunit of chorionic gonadotropin (CGB) is about 37 Mb in size and covers about 37 cM genetic distance. The ration of genetic to physical distance on 19q is therefore very close to the genomic average OF 1 cM/Mb. Estimates of physical distances for intervals between chromosome 19 markers were calculated using a mapping function which estimates distances based on the number of breaks in hybrid clone panels. The consensus genetic distances between individual markers (established at HBM10) were compared to these estimates of physical distances. The close agreement between the two estimates suggested that spontaneously broken hybrids are as appropriate for this type of study as radiation hybrids.^ All three DNA repair genes located on chromosome 19 were found to have homologues on Chinese hamster chromosome 9, which is hemizygous in CHO cells, providing an explanation for the apparent ease with which mutations at these loci were identified in CHO cells. Homologues of CKMM and TGF$\beta$ (from human chromosome 19q) and a mini-satellite DNA specific to the distal region of human chromosome 19q were also mapped to Chinese hamster 9. Markers from 19p did not map to this hamster chromosome. Thus the q-arm of chromosome 19, at least between the genes PEPD and ERCC1, appears to be a linkage group which is conserved intact between humans and Chinese hamsters. ^
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The chapter maps these trade versus culture developments in the WTO and the positions of the European Union (EU or the Union) and its member states, which were not always coherent. It also looks at the actual results of the trade versus culture contestation – that is, the rules on trade in goods and services in the WTO and how they reflect the need for more policy space in matters of cultural policy, which the EU so ardently pressed for. The chapter further analyses the evolution of both the international trade regulation and the discourse on cultural policy. This discourse has in fact undergone a major transformation in the last two decades, as it has moved from the ‘exception culturelle’ rhetoric, which dominated the Uruguay trade talks, towards a more positive but also more pro-active agenda under the slogan of cultural diversity. The EU has been a major driver of this transformation, which has succeeded in mobilising the international community and ultimately led to the adoption of the 2005 UNESCO Convention on the Protection and Promotion of the Diversity of Cultural Expressions. The chapter concludes by appraisal of the current state of the debate situating it into the broader picture of contemporary global governance. It asks how the EU could effectively pursue its cultural policy aspirations and endorse its cultural diversity agenda in a world of complexity and rapid technological change, in particular in view of the affordances of digital media.
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OBJECTIVES The aim of the study was to investigate the organization and delivery of HIV and tuberculosis (TB) health care and to analyse potential differences between treatment centres in Eastern (EE) and Western Europe (WE). METHODS Thirty-eight European HIV and TB treatment centres participating in the TB:HIV study within EuroCoord completed a survey on health care management for coinfected patients in 2013 (EE: 17 respondents; WE:21; 76% of all TB:HIV centres). Descriptive statistics were obtained for regional comparisons. The reported data on health care strategies were compared with actual clinical practice at patient level via data derived from the TB:HIV study. RESULTS Respondent centres in EE comprised: Belarus (n = 3), Estonia (1), Georgia (1), Latvia (1), Lithuania (1), Poland (4), Romania (1), the Russian Federation (4) and Ukraine (1); those in WE comprised: Belgium (1), Denmark (1), France (1), Italy (7), Spain (2), Switzerland (1) and UK (8). Compared with WE, treatment of HIV and TB in EE are less often located at the same site (47% in EE versus 100% in WE; P < 0.001) and less often provided by the same doctors (41% versus 90%, respectively; P = 0.002), whereas regular screening of HIV-infected patients for TB (80% versus 40%, respectively; P = 0.037) and directly observed treatment (88% versus 20%, respectively; P < 0.001) were more common in EE. The reported availability of rifabutin and second- and third-line anti-TB drugs was lower, and opioid substitution therapy (OST) was available at fewer centres in EE compared with WE (53% versus 100%, respectively; P < 0.001). CONCLUSIONS Major differences exist between EE and WE in relation to the organization and delivery of health care for HIV/TB-coinfected patients and the availability of anti-TB drugs and OST. Significant discrepancies between reported and actual clinical practices were found in EE.
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Talk at the Symposium "Opportunities and Challenges of Longitudinal Perspectives"
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Ultrastructural analysis of the polydnavirus of the braconid wasp Chelonus inanitus revealed that virions consist of one cylindrical nucleocapsid enveloped by a single unit membrane. Nucleocapsids have a constant diameter of 33.7 +/- 1.4 nm and a variable length of between 8 and 46 nm. Spreading of viral DNA showed that the genome consists of circular dsDNA molecules of variable sizes and measurement of the contour lengths indicated sizes of between 7 and 31 kbp. When virions were exposed to osmotic shock conditions to release the DNA, only one circular molecule was released per particle suggesting that the various DNA molecules are singly encapsidated in this bracovirus. The viral genome was seen to consist of at least 10 different segments and the aggregate genome size is in the order of 200 kbp. By partial digestion of viral DNA with HindIII or EcoRI in the presence of ethidium bromide and subsequent ligation with HindIII-cut pSP65 or EcoRI-cut pSP64 and transfection into Escherichia coli, libraries of 103 HindIII and 23 EcoRI clones were obtained. Southern blots revealed that complete and unrearranged segments were cloned with this approach, and restriction maps for five segments were obtained. Part of a 16.8 kbp segment was sequenced, found to be AT-rich (73%) and to contain six copies of a 17 bp repeated sequence. The development of the female reproductive tract in the course of pupal-adult development of the wasp was investigated and seen to be strictly correlated with the pigmentation pattern. By the use of a semiquantitative PCR, replication of viral DNA was observed to initiate at a specific stage of pupal-adult development.
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We present results on the nucleon scalar, axial, and tensor charges as well as on the momentum fraction, and the helicity and transversity moments. The pion momentum fraction is also presented. The computation of these key observables is carried out using lattice QCD simulations at a physical value of the pion mass. The evaluation is based on gauge configurations generated with two degenerate sea quarks of twisted mass fermions with a clover term. We investigate excited states contributions with the nucleon quantum numbers by analyzing three sink-source time separations. We find that, for the scalar charge, excited states contribute significantly and to a less degree to the nucleon momentum fraction and helicity moment. Our result for the nucleon axial charge agrees with the experimental value. Furthermore, we predict a value of 1.027(62) in the MS¯¯¯¯¯ scheme at 2 GeV for the isovector nucleon tensor charge directly at the physical point. The pion momentum fraction is found to be ⟨x⟩π±u−d=0.214(15)(+12−9) in the MS¯¯¯¯¯ at 2 GeV.
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The jumbo flying squid, Dosidicus gigas, support an important squid fishery off the Exclusive Economic Zone of Chilean waters. However, we only have limited information about their biology. In this study, age, growth and population structure of D. gigas were studied using statoliths from 333 specimens (386 females and 147 males) randomly sampled in the Chinese squid jigging surveys from 2007 to 2008 off the Exclusive Economic Zone of Chile. Mantle lengths (MLs) of the sample ranged from 206 to 702 mm, and their ages were estimated from 150 to 307 days for females and from 127 to 302 days for males. At least two spawning groups were identified, the main spawning peak tended to occur between August and November (austral spring group), and the secondary peak appeared during March to June (austral autumn group). The ML-age relationship was best modelled by a linear function for the austral spring group and a power function for the austral autumn group, and the body weight (BW)-age relationship was best described by an exponential function for both the groups. Instantaneous relative growth rates and absolute growth rates for ML and BW did not differ significantly between the two groups. The growth rate of D. gigas tended to be high at young stages, and then decreased after the sub-adult stage (>180 days old). This study suggests large spatial and temporal variability in key life history parameters of D. gigas, calling for the collection of more data with fine spatial and temporal scales to further improve our understanding of the fishery biology of D. gigas.
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In our late twentieth century experience, survival of an economy seems critically dependent on well established rights to private property and a return to labor that rewards greater effort. But that need not be so. History provides examples of micro-socialist economies that internally, at least, allow for little private property for participants and a constant return to labor that is independent of effort. Some such economies may even be termed 'successful,' if success is taken to mean survival over several generations. If these communities survived without conditions that are generally thought to be necessary for success, a question worth asking is how this occurred, for we can then shed some light on what really is necessary for economic survival. Addressing this issue emphasizes the critical role of time, for even if the microsocialist economies that we study here eventually became the merest shadow of their former selves, the fact that they did flourish for so long makes them a valuable counterexample, and hence, a phenomenon in need of explanation. We consider here the dairy industry of the Shakers, which was characterized by intensive efforts to increase productivity, in part through the use of market signals, but efforts that were also limited by the ideological goals of the community. The Shakers were (and are, but since it is the historical Shakers that concern this paper, the past tense will be used) a Christian communal group. Some of their distinctive beliefs included the existence of a male and female Godhead, from which followed sexual equality, and active communication between Believers (a Shaker term for members of the sect) and denizens of the spirit world. Practices of the Society (their official name is the United Society of Believers in Christ's Second Appearing, the second appearing being in the body of their foundress, an illiterate Englishwoman named Ann Lee) included pacifism, celibacy, confession of sins to elders, and joint or communal ownership of the Society's assets. Each Shaker received the same return for his or her labor: room, board, clothing, and the experience of divine proximity in a community of like minded Believers (Stein 1992).