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Host range functions of poxvirus proteins are mediated by species- specific inhibition of the antiviral protein kinase PKRHaller, Sherry LaRae January 1900 (has links)
Doctor of Philosophy / Department of Biology / Stefan Rothenburg / Vaccinia virus is the prototypic poxvirus that has been widely used as a model for investigating poxvirus biology and genetics. Like several members of the Poxviridae family, vaccinia virus can infect several different species including mice, cows and humans. Because the entry of poxviruses into a host cell relies on ubiquitously expressed surface molecules, which are found in many species, the ability of poxviruses to infect and replicate in different host cells primarily depends on their ability to subvert the host’s innate immune response. One critical barrier to infection is overcoming the general shutdown of protein translation initiated by the cellular protein kinase PKR. PKR detects cytoplasmic double-stranded (ds) RNA generated during infection by the replicating virus, which activates it to phosphorylate the alpha-subunit of the eukaryotic translation initiation factor 2 (eIF2) and suppress general translation. Poxviruses are large viruses with dsDNA genomes that encode around 200 genes. Several of these genes are known as host range genes and are important for replication in different host species and many interact with components of the host immune response to promote viral replication. Two genes in vaccinia virus, called E3L and K3L, are known inhibitors of PKR and have previously been shown to be important for virus replication in cells from different species. The molecular explanation behind their host range function, however, is unknown. The main goal of the research presented in this thesis is to determine the molecular mechanisms for the host range function of vaccinia virus E3L and K3L, particularly in different hamster host cells. Along with an analysis of vaccinia virus host range genes, we have used genome-wide comparisons between host-restricted poxviruses in the Leporipoxvirus genus to parse out the potential genomic determinants of host range restriction in this clade of poxviruses. The overarching aim of this thesis work is to better understand the molecular mechanisms for host range in poxviruses.
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Effects of date of burning on native Flint Hills range landHerbel, Carlton Homer. January 1954 (has links)
Call number: LD2668 .T4 1954 H4 / Master of Science
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Climate-Radial Growth Relationships Of Northern Latitudinal Range Margin Longleaf Pine (Pinus Palustris P. Mill.) In The Atlantic Coastal Plain Of Southeastern VirginiaBhuta, Arvind A. R., Kennedy, Lisa M., Pederson, Neil 07 1900 (has links)
Climate and longleaf pine (Pinus palustris P. Mill.) radial growth relationships have been
documented within its southern and western distribution. However, knowledge of this relationship is lacking along its northern latitudinal range margin (NLRM). Based on the principles of ecological amplitude, limiting factors, and studies of coniferous species in eastern temperate forests of the U.S., we hypothesized that the radial growth of longleaf pine in mixed pine-hardwood forests is responding to winter temperatures in southeastern Virginia. Two longleaf pine chronologies were developed to determine the relationship between radial growth and monthly temperature, precipitation, and Palmer Drought Severity Index (PDSI) via response function analysis (RFA). Results at the 0.05 level yielded significant response function coefficients with a positive response to current winter temperature and precipitation and a negative response to prior August PDSI. In studies of climate and longleaf pine radial growth in other parts of its range, winter temperature and precipitation have not shared a significant positive association with radial growth. Instead current spring and summer precipitation usually share this positive association. These findings add more evidence to an emerging pattern suggesting that winter temperatures contribute to limiting the radial growth of temperate conifers at northern range margins in the Northern Hemisphere.
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The calculation of a wind climatology of the ErzgebirgeHinneburg, Detlef 25 October 2016 (has links) (PDF)
Ausgangspunkt für die Berechnung klimatologisch gemittelter Windgeschwindigkeiten ist die mesoskalige Simulation atmosphärischer Strömungsereignisse, die von der geostrophischen Windgeschwindigkeit gesteuert werden. Der geostrophische Wind wird in 8 Richtungssektoren und Betragsklassen zu je 5m/s eingeteilt, so daß für jeden Sektor bis zu 7 Simulationen auszuführen waren. Die Simulationen wurden mit dem nicht-hydrostatischen Modell GESIMA für eine adiabatisch geschichtete Atmosphäre durchgeführt. Die statistische
Mittelung der berechneten Werte erfolgte mit Hilfe einer 10-jährigen Häufigkeitsverteilung des 850hPa-Windes der Radiosondenmessungen von Prag. Ein Vergleich mit den Beobachtungswerten einiger Bodenstationen ergibt Abweichungen bis zu lm/s über höheren Bergen. / Starting from the classification of the geostrophic wind into 8 sectors each of them splitted up into 7 classes by 5m/s, simulations with the non-hydrostatic mesoscale atmospheric model GESIMA were performed assuming adiabatic stratification of the atmosphere for each class. The climatologically averaged wind velocities are obtained by the folding with a ten-years frequency distribution of the geostrophic wind measured by the radio sonde station of Prague. Wind velocities observed at some surface stations indicate, that the simulated values can deviate from them by up to lm/s on high mountains.
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Regionale Unterschiede im Auftreten von EisablagerungenArnold, Klaus, Raabe, Armin, Tetzlaff, Gerd 25 October 2016 (has links) (PDF)
Bei der Errichtung von Windenergieanlagen in Mittelgebirgsregionen ist darauf zu achten, daß an windexponierten Standorten die Gefahr einer Vereisung der Rotorblätter besteht. Es wurden klimatologische Daten im Bereich der Mittelgebirge ausgewertet und daraus eine Karte erarbeitet, in der die jährliche mittlere Häufigkeit der Tage mit Eisablagerungen dargestellt ist. / With the installation of wind turbines in low mountain areas the hazard of ice accretions on rotor blades at windy places must be considered. Interpreting climatological datas of the low mountain areas of S. E. Germany a map has been produced which shows the annual frequencies of days ice accretions on structures occurs.
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Ekonomibyggnaders indelning i värdeområden vid taxering av lantbrukHulin, Sofie January 2016 (has links)
I Sverige används värdeområden för att fånga de variabler som påverkar värdet av ekonomibyggnader beroende av var de är belägna. Taxeringsvärdet är kopplat till marknadsvärdet. När värdeområden skapas sker en massvärdering som kan baseras på hedoniska värderingsmodeller vilket innebär att marknadsvärdet är en funktion av många olika variabler. Idag används sällan ekonomibyggnader i aktiva lantbruk då många lantbruk har lagt ner sin verksamhet under de senaste årtiondena. Detta leder till att marknadsvärdet för ekonomibyggnader inte längre påverkas av samma variabler som de en gång gjorde. Målet med arbetet är därför att utreda aktualiteten av dagens värdeområdesindelning för ekonomibyggnader som inte används i lantbruk och att utreda hur dessa ekonomibyggnader bör taxeras. Studien utreder hur marknadsvärdet för ekonomibyggnader ska uppskattas vid taxering och vilken användning ekonomibyggnader har idag. Studien ger även svar på hur marknadsvärdet för ekonomibyggnader påverkas av var de är belägna. Intervjuer har genomförts med sakkunniga inom området för att kartlägga användningen av ekonomibyggnader idag och hur marknadsvärdet för ekonomibyggnader varierar i olika delar av Sverige i relation till orterna de är belägna vid. En studie genomfördes även för att göra en jämförelse mellan marknadsvärden för ekonomibyggnader och industrier. Resultatet av studien visar att marknadsvärdet för ekonomibyggnader påverkas av närheten till städer och ”hot spots” för lokala marknader. Där det finns tillgång till kommunikationsleder är avstånden från marknadens centrum till den gräns där marknadsvärdet börjar falla längre. Ekonomibyggnader används ofta som lager, som uthyrningsstall eller till handel. Slutsatsen är att värdeområden för ekonomibyggnader kan inspireras av pristrenden för industrier utanför städer och att avkastningsmetoden bör användas vid värdering av ekonomibyggnader inför taxering. För varje enskild ort måste dock sakkunniga tillfrågas hur förhållandena ser ut i deras verksamhetsområde, då lokala marknader kan finnas. / <p>Presentationen är redan genomförd.</p>
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The contribution of seasonal climate forecasts to the management of agricultural disaster-risk in South AfricaKgakatsi, Ikalafeng Ben 06 February 2015 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. July 2014. / South Africa’s climate is highly variable, implying that the national agricultural
sector should make provision to have early warning services in place in order to
reduce the risks of disasters. More than 70% of natural disasters worldwide are
caused by weather and climate or weather and climate related hazards. Reliable
Seasonal Climate Forecasting (SCF) for South Africa would have the potential to be
of great benefit to users in addressing disaster risk reduction. A disaster is a serious
disruption of the functioning of a community or a society, causing widespread
human, material, economic or environmental losses, which exceed the ability of the
affected community or society to cope when using their own resources. The negative
impacts on agricultural production in South Africa due to natural disasters including
disasters due to increasing climate variability and climate change are critical to the
sector.
The hypothesis assumed in the study is the improved early warning service and better
SCF dissemination lead to more effective and better decision making for subsequent
disaster risk reduction in the agricultural sector. The most important aspect of
knowledge management in early warning operations is that of distributing the most
useful service to the target group that needs it at the right time. This will not only
ensure maximum performance of the entity responsible for issuing the early
warnings, but will also ensure the maximum benefit to the target group.
South Africa is becoming increasingly vulnerable to natural disasters that are afflicted
by localised incidents of seasonal droughts, floods and flash floods that have
devastating impacts on agriculture and food security. Such disasters might affect
agricultural production decisions, as well as agricultural productivity. Planting dates
and plant selection are decisions that depend on reliable and accurate meteorological
and climatological knowledge and services for agriculture. Early warning services
that could be used to facilitate informed decision making includes advisories on
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future soil moisture conditions in order to determine estimated planting times, on
future grazing capacity, on future water availability and on forecasts of the following
season’s weather and climate, whenever that is possible. The involvement of
government structures, obviously, is also critical in immediate responses and long term
interventions.
The importance of creating awareness, of offering training workshops on climate
knowledge and SCF, and of creating effective early warning services dissemination
channels is realized by government. This is essential in order to put effective early
warning services in place as a disaster-risk coping tool. Early warning services,
however, can only be successful if the end-users are aware of what early warning
systems, structures and technologies are in place, and if they are willing that those
issuing the early warning services become involved in the decision-making process.
Integrated disaster-risk reduction initiatives in government programmes, effective
dissemination structures, natural resource-management projects and communityparticipation
programmes are only a few examples of actions that will contribute to
the development of effective early warning services, and the subsequent response to
and adoption of the advices/services strategies by the people most affected. The
effective distribution of the most useful early warning services to the end-user, who
needs it at the right time through the best governing structures, may significantly
improve decision making in the agricultural, food security and other water-sensitive
sectors. Developed disaster-risk policies for extension and farmers as well as other
disaster prone sectors should encourage self-reliance and the sustainable use of
natural resources, and will reduce the need for government intervention.
The SCF producers (e.g. the South African Weather Service (SAWS)) have issued
new knowledge to intermediaries for some years now, and it is important to
determine whether this knowledge has been used in services, and if so whether these
services were applied effectively in coping with disaster-risks and in disaster
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reduction initiatives and programmes. This study for that reason also intends to do an
evaluation of the knowledge communication processes between forecasters, and
intermediaries at national and provincial government levels. It therefore, aims to
assess and evaluate the current knowledge communication structures within the
national agricultural sector, seeking to improve disaster-risk reduction through
effective early warning services. A boundary organisation is an organization which
crosses the boundary between science, politics and end-users as they draw on the
interests and knowledge of agencies on both sides to facilitate evidence base and
socially beneficial policies and programmes.
Reducing uncertainty in SCF is potentially of enormous economic value especially to
the rural communities. The potential for climate science to deliver reduction in total
SCF uncertainty is associated entirely with the contributions from internal variability
and model uncertainty. The understanding of the limitations of the SCFs as a result of
uncertainties is very important for decision making and to end-users during planning.
Disappointing, however, is that several studies have shown a fairly narrow group of
potential users actually receive SCFs, with an even a smaller number that makes use
of these forecasts
In meeting the objectives of the study the methodology to be followed is based on
knowledge communication. For that reason two types of questionnaires were drafted.
Open and closed questionnaires comprehensively review the knowledge,
understanding, interpretation of SCFs and in early warning services distribution
channels. These questionnaires were administered among the SCF producers and
intermediaries and results analysed.
Lastly the availability of useful SCFs knowledge has important implications for
agricultural production and food security. Reliable and accurate climate service, as
one of the elements of early warning services, will be discussed since they may be
used to improve agricultural practices such as crop diversification, time of planting
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and changes in cultivation practices. It was clear from the conclusions of the study
that critical elements of early warning services need to receive focused attention such
as the SCF knowledge feedback programme should be improved by both seasonal
climate producers and intermediaries, together with established structures through
which reliable, accurate and timely early warning services can be disseminated. Also
the relevant dissemination channels of SCFs are critical to the success of effective
implementation of early warning services including the educating and training of
farming communities.
The boundary organisation and early warning structures are important in effective
implementation of risk reduction measures within the agricultural sector and thus
need to be prioritised. Enhancing the understandability and interpretability of SCF
knowledge by intermediaries will assist in improving action needed to respond to
SCFs. Multiple media used by both SCF producers and intermediaries in
disseminating of SCFs should be accessible by all users and end-users. The
Government should ensure that farming communities are educated, trained and well
equipped to respond to risks from natural hazards.
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Optimisation du calcul des dispersions angulaires tridimensionnelles / Optimization of the three-dimensional angular dispersions calculationMezghani, Aïda 05 November 2010 (has links)
Ce travail de recherche traite un problème qui joue un rôle très important pour le succès desprogrammes de fabrication : le tolérancement tridimensionnel, essentiel pour définir la géométried'une pièce mécanique assurant sa meilleure fonctionnalité dans un assemblage avec uneprécision optimale.Une méthode des chaînes de cotes angulaires tridimensionnelles a été développée. Cette méthodepermet d’une part l’optimisation du calcul des dispersions angulaires tridimensionnelles etd’autre part de valider la gamme de fabrication par la vérification du respect des tolérancesimposées par le bureau d’études en tenant compte des précisions des procédés utilisés.Cette étude est basée sur l’analyse de deux fonctions paramétrées qui sont étudiées pourdéterminer le défaut fabriqué : le défaut angulaire et la longueur projetée. Le défaut angulairereprésente le cumul des défauts angulaires générés par le processus de fabrication de la pièce. Lesdéfauts angulaires sont déterminés en fonction de la précision des machines outils. La longueurprojetée de la surface tolérancée est une caractéristique qui dépend uniquement de la forme de lasurface.Ensuite, à partir de ces deux fonctions paramétrées, le défaut fabriqué est déterminé puiscomparé avec la condition fonctionnelle afin de vérifier si la gamme choisie permet en fin duprocessus de fabrication de donner une pièce conforme. / To verify the capacity of a manufacturing process to make the corresponding parts it is necessaryto simulate the defects that it generates and to analyze the correspondence of produced parts withthe functional tolerances. In order to check the capability of a manufacturing process to carry outsuitable parts, it is necessary to analyze each functional tolerance.The main objective of our work is to define a methodology of tolerancing analysis. Thedeveloped method allows to determine the manufacturing tolerances in the case of angular chainsof dimensions and to check its correspondence with the functional tolerances.The objective of this work is to analyze two parameterized functions: the angular defect and theprojected length of the toleranced surface. The angular defect represents the angular defectgenerated by the manufacturing process. It is determined according to the machine toolsprecision. We consider only the geometrical defects, making the assumption that the form defectsare negligible. The projected length of toleranced surface is a characteristic which depends onlyon the form of surface.The manufactured defect is determined from these two parameterized functions. Then it will becompared with the functional condition in order to check if the selected machining range allows,at end of the manufacturing process, to give a suitable part.
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Coach, chef eller ledare? : Skiljer sig ledarskapet åt mellan idrottsorganisationer och näringsliv?Polsten, Jacob, Svärd, Jonathan, Ekelund Lukk, Jonas January 2019 (has links)
Vårt syfte med denna uppsats har varit att öka vår förståelse för om, och i så fall hur, ledarskap skiljer sig åt mellan idrottsorganisationer och näringsliv med fokus på ledare och spelare/medarbetare. Uppsatsen har en kvalitativ ansats med semi-strukturerade intervjuer, där både ledare och spelare/medarbetare från båda organisationer intervjuats. Ledarskapen har jämförts med hjälp av The Full Range of Leadership av Bass & Bass (2008) samt The Self- Determination Theory av Ryan & Deci (2000). Våra resultat visar att ledarskapet skiljer sig åt på flera punkter, däribland mål, konflikthantering, feedback och motivation. Vi fann även likheter som bestrider tidigare forskning.
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Caracterização biológica e molecular de um isolado do Johnsongrass mosaic virus (JGMV) de Panicum maximum cv. Mombaça em São Paulo / Biological and molecular characterization of an isolate of Johnsongrass mosaic virus (JGMV) of Panicum maximum cv. Mombaça in São PauloGarcia, Viviana Marcela Camelo 11 March 2015 (has links)
Johnsongrass mosaic virus (JGMV) é uma espécie do gênero Potyvirus. A sua distribuição geográfica, até o início da década de 1990, estava limitada à Austrália e aos Estados Unidos, onde causa doença em sorgo, milho e várias gramíneas. Em 2001, o JGMV foi detectado pela primeira vez no Brasil em amostras de híbridos e variedades de milho provenientes da região de Ribeirão Preto, SP mediante análise sorológica (DAS-ELISA), e em 2013 foi detectado mediante RT-PCR em amostras de Pennisetum purpureum provenientes do Estado da Bahia. Em Fevereiro de 2012 a Clínica Fitopatológica da ESALQ/USP recebeu amostras de Panicum maximum cv. Mombaça, com sintomas de mosaico, de São Luiz do Paraitinga, SP. Exames preliminares de contrastação negativa em microscópio eletrônico de transmissão indicaram a presença de partículas virais características de potyvirus. Diante disso, o principal objetivo deste trabalho foi caracterizar o agente etiológico associado às plantas doentes de capim Mombaça mediante testes biológicos, sorológicos e moleculares. Extratos foliares de plantas sintomáticas de capim Mombaça foram inoculados mecanicamente em 69 genótipos da família Poaceae. As avaliações foram feitas com base nos sintomas e por PTA-ELISA usando antissoro policlonal contra a proteína capsidial do potyvirus produzido nesse trabalho, após purificação do isolado viral. As espécies susceptíveis foram Brachiaria brizantha, B. decumbens, B. plantaginea, Cenchrus echinatus, Echinochloa colona, E. crus-galli, E. cruspavonis, Melinis minutiflora, Panicum maximum cv. Colonião, Pennisetum setosum, Rhynchelytrum repens, Rottboellia exaltata, Sorghum bicolor BRS 332, S. bicolor BRS 509, S. bicolor x S. sudanense BRS 802 e S. verticilliflorum. Espécies cultivadas como arroz, aveia, cana-de-açúcar, centeio, milho e trigo não foram infectadas com esse isolado. O peso molecular da proteína capsidial deste potyvirus foi estimado em cerca de 33 kDa por meio de Western blot. Sequência de nucleotídeos do genoma completo (9.885 nt) obtida neste estudo revelou identidade de 82,03% com a única sequência completa do genoma de um isolado do JGMV da Austrália, depositada no GenBank. A partir dessa sequência foram obtidos oligonucleotídeos iniciadores específicos para a detecção do isolado de SP do JGMV mediante RT-PCR. / Johnsongrass mosaic virus (JGMV) is a species of the genus Potyvirus. The geographical distribution, until the early 1990s, was limited to Australia and the United States, where it causes disease in sorghum, corn and various grasses. In 2001, JGMV was first detected in Brazil in samples of hybrids and varieties of corn from the region of Ribeirão Preto, São Paulo State by serological analysis (DASELISA), and in 2013 it was detected by RT-PCR in samples of Pennisetum purpureum from the State of Bahia. In February 2012, the Disease Diagnostic Clinic ESALQ/USP received samples of Panicum maximum cv. Mombaça, exhibiting mosaic symptoms, from the region of São Luiz do Paraitinga, SP. Preliminary examination of negatively stained sap in a transmission electron microscope indicated the presence of potyvirus-like particles. Therefore, the main objective of this study was to characterize the etiologic agent associated with P. maximum cv. Mombaça diseased plants by biological, serological and molecular tests. Leaf extract from Mombaça infected plants was mechanically inoculated in 69 genotypes of the Poaceae family. Evaluations were done based on symptoms expression and PTAELISA using polyclonal antiserum against the capsid protein of the potyvirus produced in the preset work virus purification. Susceptible species were Brachiaria brizantha, B. decumbens, B. plantaginea, Cenchrus echinatus, Echinochloa colona, E. crus-galli, E. crus-pavonis, Melinis minutiflora, Panicum maximum cv. Colonião, Pennisetum setosum, Rhynchelytrum repens, Rottboellia exaltata, Sorghum bicolor BRS 332, S. bicolor BRS 509, S. bicolor x S. sudanense BRS 802 and S. verticilliflorum. Cultivated species such as rice, oats, sugarcane, rye, corn and wheat were not infected with this isolate. The molecular weight of the coat protein of this potyvirus was estimated at about 33 kDa by Western blot. The nucleotide sequence of the complete genome (9885 nt) obtained in this study showed 82.03% identity with an unique sequence for the complete genome of an isolate of JGMV from Australia, deposited in GenBank. From this nucleotide sequence, specific pair of primers was designed for the detection of the São Paulo isolate of JGMV by RT-PCR.
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