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Importance of Digitals Models of Soil Surface in the Flooding Hydraulic Simulation Importancia de los modelos digitales del terreno en la simulación hidráulica de inundaciones
Anders Pérez Brugal,Juan F. Weber,Yaismil R. Castellanos
Revista Cubana de Ingeniería , 2010, DOI: 10.1234/rci.v1i3.29
Abstract: Investigation analysed the influences of MDT′s precision in the results of the hydraulic simulation of floodings. Four digitals models of soil surface were created from different sources: three starting from vectorial cartography by contour lines of few scales and one getting from GPS devices and total station measuring. The comparison to the estimated measured error due to the utilization of simple vectorial cartography paper for the representation of riverbed and flood valleys, with the last model utilized, may assume it influence in flood simulation results. One conclusion was probed; height differences in the representation of soil surface to the same point were very wide [2,88 to 18,82 m], then the estimated water level as well the simulation of flooding area depend of the obtained cartography method, due that were found errors from 1,6 to 2,6 m and from 0,039 to 0,283 km2, that demonstrates he precision of the MDT with that the plot of land is modeled determines the results of the simulation to a large extent. En la investigación se analizó la influencia de la precisión de los modelos gigitales del terreno [MDT] en los resultados de la simulación hidráulica de inundaciones. Se crearon cuatro MDT derivados de fuentes diferentes: tres, a partir de cartografía vectorial de curvas de nivel a varias escalas y uno, producto de un levantamiento con GPS en conjunto con una estación total. Este último se estableció como punto de comparación para determinar los errores que impone el uso de dichos planos en la representación del cauce y las llanuras de inundación y revelar su influencia en los resultados de la simulación. Finalmente, en dependencia del plano utilizado, se obtuvieron divergencias de 2,88 hasta 18,82 m de altura al representar un mismo punto en el terreno, lo que influyó de manera significativa en el cálculo de altura de la lámina de agua y en la estimación del área inundada, ya que se encontraron errores de 1,6 hasta 2,6 m y de 0,039 hasta 0,283 km2 respectivamente, lo que demuestra que la precisión del MDT con que se modela el terreno determina en gran medida los resultados de la simulación.
Dynamic Knowledge—A Century of Evolution  [PDF]
Georg F. Weber
Sociology Mind (SM) , 2013, DOI: 10.4236/sm.2013.34036
Abstract:

The discovery of non-linear systems dynamics has impacted concepts of knowledge to ascribe to it dynamic properties. It has expanded a development that finds its roots more than hundred years ago. Then, certainty was sought in systems of scientific insight. Such absolute certainty was inevitably static as it would be irrevocable once acquired. Although principal limits to the obtainability of knowledge were defined by scientific and philosophical advances from the 1920s through the mid-twentieth century, the knowledge accessible within those boundaries was considered certain, allowing detailed description and prediction within the recognized limits. The trend shifted away from static theories of knowledge with the discovery of the laws of nature underlying non-linear dynamics. The gnoseology of complex systems has built on insights of non-periodic flow and emergent processes to explain the underpinnings of generation and destruction of information and to unify deterministic and indeterministic descriptions of the world. It has thus opened new opportunities for the discourse of doing research.

Abstammungsbewertung der zuchtstiere propektiv und retrospektiv
F Weber
Genetics Selection Evolution , 1976, DOI: 10.1186/1297-9686-8-2-303b
Abstract:
Prüfungen in tierzucht für studenten
F Weber
Genetics Selection Evolution , 1977, DOI: 10.1186/1297-9686-9-1-134d
Abstract:
Praktische aspekte von rassenvergleichsversuchen beim rind
F Weber
Genetics Selection Evolution , 1975, DOI: 10.1186/1297-9686-7-2-234a
Abstract:
Possible Consequences from Commercialisation of Organ Donation within Medical Profession
F. Weber
Transplantationsmedizin , 2003,
Abstract: In the continuous discussion about financial incentives for organ donation promotors of a controlled trade system hope for an increase while opponents suspect a decrease in the number of organs available for transplantation. For both assumptions evidence is lacking. Physicians are essential partners for cooperation with transplant centers in cadaveric organ donation. It is assumed that their attitude to donate their own organs after death will influence their readiness to participate in the cooperation process. In an anonymous questionnaire which was completed in 1994/95 (N=759) and 1999 (N=500) by clinic and primary care physicians in the region of KV Nordrhein their attitudes towards various items concerning organ donation and transplantation was evaluated. For most items the answers given in 1999 were the same as in 1994/95 but the willingness to donate organs after death had declined significantly by 10%. In 1994/95 there was only a 8% lower consent rate to own organ donation for those physicians who believed that organ trade was possible in Germany compared to those who judged organ trade impossible (82 vs. 90%, difference not significant), while in 1999 this difference had increased to 21% (65 vs. 86%, p=0.005). These data are more in favour of the assumption that the readiness of physicians as cooperating partners in the process of cadaveric organ recruitment will diminish and consequently the total number of organs for transplantation will decrease if a system of financial incentives for organ donation is installed.
Risk management of paratuberculosis in dairy herds
Maarten F Weber
Irish Veterinary Journal , 2006, DOI: 10.1186/2046-0481-59-10-555
Abstract: The likelihood of paratuberculosis occurring in the herd is related to the regional herd-level prevalence of paratuberculosis and the herd management (e.g., introducing animals from other herds). The economic impact of paratuberculosis includes production losses due to subclinical and clinical cases, losses due to increased replacement of animals and costs of control measures. Furthermore, a reduction of the price of milk from infected herds might result from consumer concerns about the zoonotic potential of paratuberculosis.Measures that reduce the likelihood of paratuberculosis occurring in a herd and its impact include preventive management measures (e.g., closed herd management and an effective separation of susceptible young stock from adult cattle), test-and-cull schemes for known infected herds and quality assurance schemes for test-negative herds. Quality assurance schemes for test-negative herds, such as schemes for 'low-Map bulk milk' and 'Map-free' herds, aim at safeguarding or increasing the profitability of these herds.Keys to success of risk management of paratuberculosis include realistic expectations of the results of paratuberculosis control, quality assurance and control programmes that are appreciated by farmers and incentives for farmers to participate in such programmes.Paratuberculosis (Johne's disease) is a chronic inflammatory bowel disease, primarily affecting ruminants. The aetiologic agent is Mycobacterium avium subsp. paratuberculosis (Map). Losses associated with paratuberculosis include failure to thrive, reduced milk production, reduced reproductive performance, reduced culling value and increased replacement rate [52,16]. Moreover, there are potential concerns about the safety of dairy products [40].Risk management of paratuberculosis is the process of identifying measures or actions that reduce the risk of exposure of a herd to Map to an acceptable level. This risk is a function of the probability of an adverse effect and the severit
Superconductivity-Induced Distortions of Phonon Lineshapes in Niobium
F. Weber,L. Pintschovius
Physics , 2010, DOI: 10.1103/PhysRevB.82.024509
Abstract: Superconductivity-induced changes of phonon lineshapes in niobium have been re-investigated by high-resolution inelastic neutron scattering. We show that the changes go beyond a simple change in lifetime and frequency when the phonon frequency is close to the superconducting energy gap $2\Delta$. The observed lineshapes in elemental niobium are qualitatively similar to those found previously in borocarbide superconductors and agree very well with those predicted by the theory of Allen et al. [PRB 56, 5552 (1997)]. Our results indicate that the peculiar phonon lineshapes in the superconducting state predicted by the theory of Allen et al. are a general phenomenon and not restricted to a particular class of compounds.
QCD in neutron stars and strange stars
F. Weber,R. Negreiros
Physics , 2011, DOI: 10.1063/1.3587579
Abstract: This paper provides an overview of the possible role of Quantum Chromo Dynamics (QDC) for neutron stars and strange stars. The fundamental degrees of freedom of QCD are quarks, which may exist as unconfined (color superconducting) particles in the cores of neutron stars. There is also the theoretical possibility that a significantly large number of up, down, and strange quarks may settle down in a new state of matter known as strange quark matter, which, by hypothesis, could be more stable than atomic nuclei. In the latter case new classes of self-bound, color superconducting objects, ranging from strange quark nuggets to strange quark stars, should exist. The properties of such objects will be reviewed along with the possible existence of deconfined quarks in neutron stars. Implications for observational astrophysics are pointed out.
Bunyaviridae RNA Polymerases (L-Protein) Have an N-Terminal, Influenza-Like Endonuclease Domain, Essential for Viral Cap-Dependent Transcription
Juan Reguera,Friedemann Weber,Stephen Cusack
PLOS Pathogens , 2010, DOI: 10.1371/journal.ppat.1001101
Abstract: Bunyaviruses are a large family of segmented RNA viruses which, like influenza virus, use a cap-snatching mechanism for transcription whereby short capped primers derived by endonucleolytic cleavage of host mRNAs are used by the viral RNA-dependent RNA polymerase (L-protein) to transcribe viral mRNAs. It was recently shown that the cap-snatching endonuclease of influenza virus resides in a discrete N-terminal domain of the PA polymerase subunit. Here we structurally and functionally characterize a similar endonuclease in La Crosse orthobunyavirus (LACV) L-protein. We expressed N-terminal fragments of the LACV L-protein and found that residues 1-180 have metal binding and divalent cation dependent nuclease activity analogous to that of influenza virus endonuclease. The 2.2 ? resolution X-ray crystal structure of the domain confirms that LACV and influenza endonucleases have similar overall folds and identical two metal binding active sites. The in vitro activity of the LACV endonuclease could be abolished by point mutations in the active site or by binding 2,4-dioxo-4-phenylbutanoic acid (DPBA), a known influenza virus endonuclease inhibitor. A crystal structure with bound DPBA shows the inhibitor chelating two active site manganese ions. The essential role of this endonuclease in cap-dependent transcription was demonstrated by the loss of transcriptional activity in a RNP reconstitution system in cells upon making the same point mutations in the context of the full-length LACV L-protein. Using structure based sequence alignments we show that a similar endonuclease almost certainly exists at the N-terminus of L-proteins or PA polymerase subunits of essentially all known negative strand and cap-snatching segmented RNA viruses including arenaviruses (2 segments), bunyaviruses (3 segments), tenuiviruses (4–6 segments), and orthomyxoviruses (6–8 segments). This correspondence, together with the well-known mapping of the conserved polymerase motifs to the central regions of the L-protein and influenza PB1 subunit, suggests that L-proteins might be architecturally, and functionally equivalent to a concatemer of the three orthomyxovirus polymerase subunits in the order PA-PB1-PB2. Furthermore, our structure of a known influenza endonuclease inhibitor bound to LACV endonuclease suggests that compounds targeting a potentially broad spectrum of segmented RNA viruses, several of which are serious or emerging human, animal and plant pathogens, could be developed using structure-based optimisation.
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