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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Morphologisch-funktionelle Untersuchungen an Endometriumbioptaten von zyklischen und azyklischen Maultierstuten

Huth, Heidrun 12 October 2011 (has links)
Ziel der vorliegenden Arbeit war die ausführliche histomorphologische Charakterisierung der endometrialen Funktionsmorphologie sowie die Darstellung der Ki-67 Antigen, Östrogen- und Progesteronrezeptor-Expression am Endometrium zyklischer und azyklischer Maultierstuten unter Einbeziehung klinischer und endokrinologischer Daten. Die Ergebnisse sollten mit den zu diesem Thema bereits vorliegenden Erkenntnissen bei der Pferdestute verglichen werden. Zu diesem Zweck wurden 97 Endometriumbioptate von sechs klinisch-gynäkologisch gesunden Maultierstuten im Alter von 13 bis 23 Jahren (immun-)histologisch ausgewertet. Die Bioptate waren zuvor in Abständen von zwei bis zehn Tagen und über einen Zeitraum von 4 Monaten (April bis August 2004), im Fall einer Stute von sieben Monaten (April bis November 2004) entnommen worden. Für jedes der Tiere lagen detaillierte Informationen über die klinisch-gynäkologischen Befunde und die Serumhormonkonzentrationen zu den entsprechenden Entnahmezeitpunkten vor (BARTMANN et al. 2008). Vorberichtlich zeigen zwei der Tiere im Untersuchungszeitraum ein unregelmäßiges Zyklusgeschehen mit ovariellen Funktionskörpern sowie variablen Serumöstradiol- und –progesteronkonzentrationen, bei vier Maultieren wird klinisch eine Azyklie mit inaktiven Ovarien sowie niedrigen, wenig schwankenden Serumhormonwerten dokumentiert. Bei den Tieren der zyklischen Gruppe (n=2) variiert die endometriale Funktionsmorphologie sehr stark. In nahezu allen untersuchten Endometriumbioptaten findet sich eine ausgeprägte endometriale Fehldifferenzierung. Diese kann anhand ihres Erscheinungsbildes nach den bei der Pferdestute bekannten histomorphologischen Kriterien (HÄFNER 1999, SCHOON et al. 1999b) eingeteilt werden. Sie tritt bei den untersuchten Maultieren als irreguläre glanduläre oder aber als irreguläre und ungleichmäßige glanduläre Differenzierung in Erscheinung und wird mit einem inaktiven, sekretorischen oder proliferativen Grundcharakter vorgefunden. Maultierstute 1 zeigt im Untersuchungszeitraum eine variable endometriale Proliferationsaktivität (Marker Ki-67 Antigen), bei Maultierstute 2 ist sie konstant schwach ausgeprägt. Es lässt sich kein charakteristisches, zyklusphasenabhängiges, positiv an die Steroidhormonrezeptorexpression gekoppeltes Expressionsmuster, wie es bei der Pferdestute bekannt ist, nachweisen. Die ER- und PR-Expression zeigt bei den zyklischen Maultierstuten ein sehr variables Bild (insbesondere Maultierstute 1), welches dem bei zyklierenden Pferdestuten während der physiologischen Decksaison nicht entspricht. Aufgrund der Diskrepanz zwischen klinischen Daten, Serumhormonkonzentrationen, endometrialer Funktionsmorphologie und Hormonrezeptorstatus bei den zyklischen Maultierstuten kann festgestellt werden, dass es bei den untersuchten Tieren nicht möglich ist, anhand der morphologisch-funktionellen Gegebenheiten am Endometrium auf den klinischen Zyklusstand zu schließen und vice versa. Die erhobenen Befunde sind in ihrer Gesamtheit am ehesten vergleichbar mit den Verhältnissen bei Pferdestuten in den Übergangszyklen zwischen Winteranöstrus und physiologischer Decksaison. Bei der Gruppe der azyklischen Maultiere (n=4) findet sich in allen untersuchten Endometriumbioptaten eine inaktive endometriale Funktionsmorphologie. Diese passt grundsätzlich zu dem klinischen Vorbericht der Azyklie mit inaktiven Ovarien und niedrigen, wenig schwankenden Serumöstradiol- und -progesteronkonzentrationen. In der Mehrzahl der Bioptate liegt eine Irregularität der glandulären Epithelien vor und in einigen Fällen treten hyperplastische und hypersekretorische Drüsenareale auf. Diese Befunde können, anlehnend an die Erkenntnisse bei der Pferdestute, als Kennzeichen einer endometrialen Fehldifferenzierung interpretiert werden (HÄFNER 1999, SCHOON et al. 1999b). Im Zusammenhang mit der schwachen endometrialen Proliferationsaktivität und der variablen ER- und PR-Expression lässt sich eine deutliche Ähnlichkeit zu den Befunden bei Pferdestuten im Winteranöstrus bzw. im Anöstrus während der physiologischen Decksaison finden (AUPPERLE et al. 2003, GOCKELN et al. 2006). Die möglichen Ursachen der endometrialen Fehldifferenzierung bei den Maultierstuten können im Rahmen der durchgeführten Untersuchungen nicht abschließend geklärt werden. Es ist jedoch denkbar, dass, analog zur Pferdestute, eine ovariell oder zentral bedingte Dysregulation und/oder eine Störung auf der Effektor/Rezeptor-Ebene vorliegen können. Die Hauptursache für die Infertilität bei Maultierstuten besteht in den chromosomal bedingten Störungen im Ablauf der Meiose der Keimzellen (WODSEDALEK 1916). Aufgrund der eigenen Untersuchungsergebnisse kann jedoch angenommen werden, dass die diagnostizierte endometriale Fehldifferenzierung, die variable Steroidhormonrezeptor-Expression sowie das Vorliegen degenerativer endometrialer Alterationen, z.B. der Endometrose, in Anlehnung an die Erkenntnisse bei der Pferdestute, zusätzliche Faktoren darstellen könnten, die zur Unfruchtbarkeit der Maultiere beitragen. Die Ergebnisse der vorliegenden Arbeit beruhen jedoch lediglich auf der Untersuchung von sechs Maultierstuten und sollten aus diesem Grund nicht unkritisch auf die Gesamtpopulation der Maultiere übertragen werden. Weitere Verlaufsuntersuchungen an einem größeren Tiergut in verschiedenen Altersgruppen inkl. Betrachtung der Hypophysenhormone FSH und LH könnten zur Aufklärung der Ursache sowie der Bedeutung der endometrialen Fehldifferenzierung für die Infertilität beim Maultier beitragen. / The aim of the present study was a detailed histomorphological characterization of the functional morphology and the evaluation of Ki-67 antigen, estrogen and progesterone receptor expression patterns in the endometrium of cyclic and non-cyclic mule mares, with respect to clinical and endocrinological data. The results were to be compared with corresponding observations in the endometrium of horse mares. For this purpose 97 endometrial biopsies from six clinically and gynaecologically healthy mule mares, aged between 13 and 23 years, were evaluated histologically and immunohistochemically. The biopsies were taken in intervals from two up to ten days over a period of four months (April to August 2004), in one mare over seven months (April to November 2004). Detailed information was given about clinical and gynaecological findings. The serum hormone concentrations for each day of biopsy sampling were determined (BARTMANN et al. 2008). According to the clinical record two of the animals show an erratic estrous cycle associated with the occurrence of corpora lutea and follicles on the ovaries during the whole period of investigation. Additionally, variable plasma estrogen and progesterone values are found. Four mules reveal acyclia including inactive ovaries and constant low serum hormone levels. In the animals of the cyclic group (n=2) the endometrial functional morphology varies to a great extend. In almost every investigated endometrial biopsy a marked endometrial maldifferentiation can be detected. It is classified according to common histomorphological criteria used for the endometrium of horse mares (HÄFNER 1999, SCHOON et al. 1999b). Endometrial maldifferentiation of the mules investigated occurs as irregular glandular or irregular and unequal differentiation and appeares in combination with a proliferative, secretory or inactive functional morphology. Mule 1 shows variable and mule 2 constant low endometrial Ki-67 expression patterns during the period of investigation. In contrast to horses, no characteristic, stage of cycle- or steroid hormone receptor expression-dependent proliferation activity can be observed with the mule mares of the present study. The expression of estrogen and progesterone receptors is highly variable in the animals of the cyclic group (especially in mule 1). These findings do not correspond to the ones in horse mares during the physiological breeding season. Due to the discrepancy between clinical data, serum hormone values, endometrial functional morphology and hormone receptor expression in the investigated mules, a conclusion from the clinical stage of cycle to morpho-functional conditions in the endometrium and vice versa seems to be impossible. The results of the present study are most likely comparable with findings in horse mares during the transitional period between winter anestrus and the physiological breeding season. The mules of the acyclic group (n=4) reveal an inactive endometrial functional morphology in all investigated endometrial biopsies. This finding basically corresponds to the clinical record of acyclia associated with inactive ovaries and rather constant serum estrogen and progesterone concentrations. In the case of these animals a majority of the investigated endometria show irregular glandular epithelia. In some areas hyperplastic and hypersecretory glands can be seen. According to observations in horse mares these findings can be interpreted as signs of endometrial maldifferentiation (HÄFNER 1999, SCHOON et al. 1999b). In connection with the weak proliferation activity and the variable ER- and PR-expression patterns seen in the acyclic mules, these results resemble findings in horses during winter anestrus or anestrus during the breeding season (AUPPERLE et al. 2003, GOCKELN et al. 2006). Within the present study the possible reasons for endometrial maldifferentiation in mules could not be finally evaluated. But it seems possible that, like in horse mares, an ovarian or central dysregulation and/or dysfunction regarding the level of receptors and effectors could play a certain role. Infertility in she-mules is mainly due to the chromosomal abnormalities during meiosis of germ cells (WODSEDALEK 1916). According to the findings in horse mares, the results of this investigation indicate that the diagnosed endometrial maldifferentiation, the variable expression of steroid hormone receptors and the presence of endometrial degenerative lesions (e.g. endometrosis) could be additional factors that possibly lead to sterility in mule mares, too. Due to the small number of individuals examined in this study, the results should not uncritically be applied to the whole population of mules. Further clinical, histological and immunohistochemical investigations, including the pituitary hormones FSH and LH as well as the use of a larger number of animals at different stages of age, could lead to a better understanding of the causes of endometrial maldifferentiation and its relevance for the infertility in mules.
122

Mule Deer Highway Mortality in Northeastern Utah: An Analysis of Population-Level Impacts and a New Mitigative System

Lehnert, Mark E. 01 May 1996 (has links)
Rerouting highways to accommodate construction of the Jordanelle Reservoir in northeastern Utah caused a dramatic increase in vehicle collisions with mule deer (Odocoileus hemionus). I evaluated the effectiveness of a new system of highway crosswalk structures installed to reduce deer losses and preserve seasonal migrations. In addition, I constructed computer simulation models to investigate how highway mortality has impacted the Jordanelle deer population. The crosswalk system restricted deer crossings to specific, well-marked areas along highways where motorists could anticipate them. Subsequent to installation, mortality declined 42.3% and 36.8% along a four-lane and two-lane highway, respectively. I was unable to statistically demonstrate that observed mortality reductions were a direct result of the crosswalk system. The potential applicability of the structures, however, should not be dismissed. Reduced deer use of the highway right-of-way (ROW), the apparent maintenance of migratory behavior, and observations of animals crossing within crosswalk boundaries indicate the system warrants further testing. Lack of motorist response to crosswalk warning signs, the tendency for foraging deer to wander outside crosswalk boundaries, and the ineffectiveness of ROW escape gates contributed to most treatment area mortalities. I offer design modifications that address these shortcomings. Four years of field data revealed that highway mortality at Jordanelle was inversely density-dependent, removed between 5.6% and 17.4% of the population each year, and disproportionately impacted bucks. I incorporated this information into 3 competing simulation models in which highway losses operated in a strictly additive, partially compensatory, or strictly compensatory manner. The partial compensation model most closely tracked observed population dynamics, suggesting that highway losses were not completely offset by reductions in other mortality sources. Highway mortality apparently worsened a population crash initiated by severe winter conditions, and may be slowing the recovery. The disproportionate loss of bucks along roads altered sex ratios of simulated populations. Mitigative efforts should target road-kill reductions >60% to avoid population declines predicted by the partial compensation model. Annual variation in demographic parameters offset the impacts of highway mortality at high population levels. At low population levels, however, highway mortality was severe enough to drive declining population trends.
123

Déterminisme biologique de la variabilité de la fonte lipidique à la cuisson du foie gras de canard / Biological determinism of the variability of fat loss during cooking of duck 'foie gras'

Théron, Laëtitia 21 November 2011 (has links)
Les objectifs de ce travail sont d'identifier les mécanismes biologiques impliqués dans le déterminisme de la variabilité de la fonte lipidique à la cuisson du foie gras de canard, et de définir des marqueurs de la fonte. Pour répondre à ces objectifs, nous avons choisi de conduire une caractérisation du tissu hépatique, selon son comportement ultérieur à la cuisson, basée sur une approche intégrée combinant de la biochimie, de la protéomique et de l'histologie. D'une part, l'expression différentielle des protéines hépatiques à l'abattage des animaux et au cours de la réfrigération, semble indiquer que le niveau de fonte pourrait être relié à des stades de développement de stéatose différents. Les animaux du groupe ‘Fonte faible' se distinguent de ceux du groupe ‘Fonte élevée' par un ‘profil d'accrétion' avec la surexpression de protéines du métabolisme énergétique par exemple, indiquant des mécanismes de synthèse et d'accumulation de lipides. A l'inverse, les animaux du groupe ‘Fonte élevée' présentent la surexpression de protéines de réponse au stress, ce qui pourrait indiquer un stade de stéatose plus avancé. Au cours de la réfrigération, la diminution globale de l'expression des protéines semble plus marquée dans le groupe ‘Fonte faible'. Dans le groupe ‘Fonte élevée', la surexpression de protéines du cytosquelette après réfrigération suggère un niveau de protéolyse plus important. D'autre part, les observations histologiques montrent des modifications de la morphologie des gouttelettes lipidiques dans le foie gras cru et au cours de la cuisson. Il semble que la fonte soit d'autant plus importante quand des fusions de gouttelettes lipidiques surviennent dans le produit cru. De plus, lors de la cuisson, les observations sur foies gras du groupe ‘Fonte élevée' révèlent une densification de la matrice non lipidique plus importante. Ces changements morphologiques et structuraux pourraient correspondre à un tissu plus fragile et donc plus sensible à la fonte lipidique. L'ensemble des résultats acquis dans ce projet permet de formuler une hypothèse sur le déterminisme biologique de la fonte lipidique même si certains mécanismes identifiés restent à confirmer. De plus, la relation entre l'aptitude à la stéatose et la qualité technologique du foie gras est une piste à explorer afin de mieux comprendre la variabilité de la fonte lipidique à la cuisson observée lors de la cuisson du foie gras de canard. / This work aims to identify the biological mechanisms involved in the determinism of variability of fat loss during cooking of duck ‘foie gras'. To achieve this objective, we carried out a characterization of liver tissue, according to its later behaviour during cooking, and based on an integrated approach combining biochemistry, proteomic and histology. On the one hand, the differential expressions of proteins early post mortem and during chilling indicate a different state of steatosis between the low and high fat loss groups. Livers with low fat loss during cooking were still in anabolic processes with regards to energy metabolism and protein synthesis, whereas livers with high fat loss during cooking developed cell protection mechanisms. The overall expression of proteins in the low ionic strength fraction was lower after chilling which revealed a down regulating effect of chilling on biological processes. In the high ionic strength fraction, the results showed an over expression after chilling of proteins from cytoskeleton and their associated proteins. This suggests that the variability of technological yield observed in processing plants could be explained by different state of ageing of fatty livers during chilling, most likely associated to different proteolytic pattern. On the other hand, the histological observations showed that, in raw livers, the lipid droplets were nearly spherical while after cooking, they were larger and lost their spherical shape. We also observed a decrease in the number of droplets after cooking, probably due to droplet fusion caused by the heat treatment. Fat loss during cooking was higher when there was more fusion of lipid droplets before cooking. Furthermore, it seemed that the effect of cooking on liver tissue was different between the two fat loss groups. These morphological modifications could mark a fragility of the tissue associated with a higher fat loss during cooking. All the results acquired in this work allowed us to draw a hypothesis on the biological determinism of cooking losses eventhough some of the identified mechanisms still need to be confirmed. The relationship between the potential to develop steatosis and the technological quality of ‘foie gras' deserves further studies in order to better understand the variability in fat loss during cooking observed in processing plants.
124

Open Source Enterprise Service Bus : Analyzing impact and value in a large organization

Bagherinia, Sharareh January 2013 (has links)
System integration is a challenging task for large organizations since they must manage complex IT infrastructures, and utilize hundreds of applications that cause a myriad of complications as a result of rapidly evolving systems and technologies. Over time customer requirements and the automation of internal business functions forced the gigantic service providers to develop and buy applications for different purposes. Not many years before, the applications in an organization were usually separated silos, specifically designed to answer a particular problem. However, this way of working was not efficient. It is not impossible to design one application that runs the total business, however, in reality it can't respond to all the needs inside an organization. In most cases the applications need to interact with each other and to reuse functionalities or data. At this point the concept of integrating systems first came to existence.The progress in computer science and information technology has also affected the way that integration between applications was developed and designed over the years. This shows that there's always some new method that should be studied and investigated. In recent years, the Enterprise Service Bus has come to the market and there are many vendors in the market claiming that they have produced the exact solution needed for requirements of organizations.In this work, the attempt was to construct an understanding of the Enterprise Application Integration practices and methods which have been utilized over the years. Mixed methods research a combination of interviews and questionnaire, and Design Science Research methods were used to generate empirical results. While the first two methods was used to supply the input for challenges of system integration, the DSR build and evaluate method was employed to test the ESB product. The criteria for the test were developed mostly as the outcome of interviews and the questionnaire as the main challenge. The aim was to verify efficiency and effectiveness of the selected and proposed ESB under special designed DSR build and evaluate phases.As a result of both theoretical and empirical studies in combination with selection of different methods in Information System research, the work presents a knowledge foundation for organizations with the aim to make a change in their current system integration practices and patterns utilizing approaches facilitated by ESB products.
125

Competition Dynamics Within Communities of Desert Wildlife at Water Sources

Hall, Lucas Keith 01 June 2016 (has links)
Water is a vital resource for species inhabiting arid and semi-arid regions and can shape the biotic communities that we observe. Because water is considered a limiting resource for many species in desert environments, there is the potential for competitive interactions between species to occur at or around water sources. For this dissertation I tested hypotheses related to resource competition among different species of wildlife in the Great Basin and Mojave Deserts of western Utah. Chapter one evaluated the influence of feral horses (Equus caballus) on patterns of water use by communities of native birds and mammals. Chapter two determined if feral horses competed with pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) for access to water. In chapters one and two, we found evidence that horses compete with native wildlife for water. In chapter one, horses were associated with decreased richness and diversity of native species at water sources. Native species also had fewer visits and spent less time at water sources frequented by horses. In chapter two, we found that pronghorn and mule deer used water sources less often where horse activity was high. There were also significant differences in temporal activity for pronghorn, but not mule deer, at horse-occupied sites versus sites where horses were absent or uncommon. Our results indicated that horses spatially and temporally displaced other species at water sources providing evidence of a negative influence on how communities of native wildlife access a limited resource in an arid environment. Chapter three assessed whether dominant carnivores (coyote (Canis latrans) and bobcat (Lynx rufus)) negatively influenced the spatial use of water sources by the subordinate kit fox (Vulpes macrotis). Our results did not reveal strong negative associations between kit fox visits to water sources and visits by dominant carnivores; in fact, dominant carnivores contributed very little to the use of water by kit foxes. Instead, kit fox visits were more closely associated with habitat features at water sources. Our findings indicate that dominant carnivores are not the primary driver of use of water sources by subordinate carnivores. Chapter four evaluated whether a simulated loss of water due to climate change/increased human use would differentially affect desert bats based on flight morphology and maneuverability. When we experimentally reduced surface area of water sources, larger, less-maneuverable bats experienced a 69% decrease in drinking success and increased competition with smaller, maneuverable bats. Anticipated reductions in the sizes of water sources due to climate change may lead to species with less maneuverability being unable to access water efficiently and facing increased competition from more agile bats.
126

Processus et Bilans d'altération en milieu tropical (bassin versant de Mule Hole, Inde du Sud) : Sensibilité à la Composition Minéralogique et au Climat

Violette, Aurélie 27 September 2010 (has links) (PDF)
L'objectif de cette thèse est d'améliorer les connaissances sur les processus et les facteurs de contrôle des flux d'altération chimiques à l'échelle d'un petit bassin versant tropical (Mule Hole, Inde du Sud). Le rôle de la minéralogie et du climat est étudié grâce à la modélisation. Dans la première partie du travail, les sols (fersialsols, vertisols) et la roche mère (gneiss) sont caractérisés minéralogiquement et chimiquement afin de procéder, dans la seconde partie, à la modélisation des processus. Le modèle géochimique est couplé avec un modèle hydrologique. Premièrement, les processus actuels sont étudiés. Le modèle est calibré grâce à la composition chimique du ruisseau et de la nappe. Les flux d'altération à l'échelle du bassin sont reproduits. Ils mettent en évidence le rôle prépondérant de l'altération des smectites (5% volumique dans les sols) sur le bilan d'altération du bassin. Finalement, des tests de sensibilité à la minéralogie et au climat sont réalisés.
127

Water Balance Studies In A Small Experimental Forested Watershed, South India

Murari, Raja Raja Varma 07 1900 (has links)
Forested watersheds play a dominant role in the global hydrological cycle. Very few experimental observatories especially in tropical forested regions of India have been undertaken. This study has been initiated for this reason and to gain insights into functioning of the hydrological system in such climatic conditions. This study involves experimental setup of a watershed, it’s monitoring till date, modelling of the hydrological processes observed and the challenges in modelling components of the water balance in this watershed. A Small Experimental Watershed of 4.3 Km2 was set up at Mule Hole, in South India along the Kerala-Karnataka State borders, and is situated inside the Bandipur National park. After an overview of watershed studies, review of literature related to forest watershed studies and processes in the first two chapters, Chapter 3 introduces the study area, Mule Hole Experimental Watershed and explains the methodology used to study this watershed. Model SWAT was used initially to simulate the water balance components. A brief description of the model, methodology adopted and discussion on the results obtained is presented in Chapter 4. The watershed initially modelled as an ungauged watershed using the default parameters in the model, simulated very high groundwater contribution to the runoff. The calibrated model although performed favourably for annual average values and monthly calibration, the daily calibration was unsatisfactory. An auxiliary study on quantification of actual and potential evapotranspiration (ET0) has been carried out in Chapter 5 . Ten methods including Penman-Montieth were compared and evaluated for efficacy of the methods. All methods except for Hargreaves method showed agreement with the Penman-Montieth for annual average values. Priestly-Taylor method was found be the best estimator in comparison with Penman-Montieth method, when used to estimate AET. Adjusted Hargreaves and FAO Blaney -Criddle method were found to be very useful when few or limited climatic data were available for estimation of Potential evapotranspiration. A multidisciplinary approach of estimating recharge consisting of chloride mass balance technique coupled with study of water table fluctuations and groundwater flow analytical modelling has been attempted in Chapter 6. Direct and localized recharge was estimated at 45 mm/yr and indirect recharge 30 mm/yr for the monitored years in the watershed. The low values of recharge rates implied an unexpected very high evapotranspiration rate. It may be inferred that in the absence of groundwater flow to the stream, the recharge joins groundwater flow as outflow of the hydrologic system. An integrated lumped model incorporating the regolith zone and the capability of the tree roots to access this store is presented in Chapter 7. The model was able to simulate the pattern of lag-time between water table rise was observed in shallow piezometers in comparison with hillslope piezometers. The patterns of water table variation among the different hillslope piezometers suggest that they are linked with local processes and not by a regional aquifer dynamics. This study shows that water uptake, combined with the spatial variability of regolith depth, can account for the variable lag time between drainage events and groundwater rise observed for the different piezometers. Chapter 8 discusses the results, conclusions derived from this study and possibility of further scope of studies.
128

Productivity, Cost and Environmental Damage of Four Logging Methods in Forestry of Northern Iran

Badraghi, Naghimeh 04 July 2014 (has links) (PDF)
Increasing productivity, reducing cost, reducing soil damage, reducing the impact of harvesting on standing tree and regeneration are all very important objectives in ground skidding system in the management of the Hyrcanian forest. The research carried out to obtain these objectives included four logging methods, tree length method (TLM), long length method (LLM), short length method (SLM), and wood extraction by mule (mule) in northern Iran. In order to determine the cost per unit, time study techniques were used for each harvesting method, time study data are shifted to logarithmic data based on 10. On the basis of the developed models simulated, 11 skidding turns are simulated and the unit cost are estimated depending on the diameter of the log (DL), skidding distance (SD), and the winching distance (WD) for 11 different cycles with TLM, LLM and SLM. The results showed that on average, the net costs per extraction of one cubic meter of wood were 3.06, 5.69, 6.81 and 34.36 €/m3 in TLM, LLM, SLM and mule. The costs depending on diameter of log (DL), skidding distance (SD) and winching distance (WD) showed that the most economical alternative for Northern Iran is TLM. In the cut-to-length system, the costs of both alternatives LLM, SLM were significantly dependent on DL. , thus the result of this study suggests that as long as the diameter of the felled trees is less than 40 cm, the cut-to-length system is not an economical alternative, whilst the cut-to-length method can be applied for trees with a diameter more than 40 cm. Where diameters are more than 40 cm TLM it is more economical than SLM, however it was not significantly different. Depending on SD in short skidding distance SLM is preferable to LLM but in cases of long skidding distance LLM is more economical than SLM. The winching distance affect was not a factor on cost. To assess the damage on seedlings and standing trees a 100% inventory method was employed in pre-hauling and post-hauling, alongside of skidding trails, winching strips and mule hauling with a 12m width. To chose the best alternative depending on standing damage the Analysis of multiple criterial approval (MA) was applied. The amount of trees damaged by winching operation were 11.89% in TLM, 14.44% in LLM 27.59%, SLM and 0 stem and by skidding operation were 16.73%, 3.13% and 8.78% of total trees in TLM, LLM and SLM. In the winching area about 14%, 20%, 21% and 6 % of the total regeneration was damaged by TLM, LLM, SLM and mule and the skidding operation damaged 7.5% in TLM, 7.4 % LLM and 9.4% in SLM. The friendliest alternative to residual standing was mule but in manual method (where the wood extraction is done by skidder) MA showed that the best alternative depending on residual damage is LLM. To determine the degree of soil compaction a core sampling technique of bulk density was used. Soil samples collected from the horizontal face of a soil pit at 10 cm depth soil core, at 50m intervals on skid trials, in winching strips and control are (no vehicles pass) a soil sample was taken at 10m intervals in the hauling direction of the mule. In order to determine the post-harvesting extent of disturbance on skidding trails by skidding operations, the disturbed widths were measured at 50 m intervals along the skid trails. In the winching area, where the winched logs created a streak of displaced soil, the width of the displaced streak was measured at 5 m interval along the winching strip. In mule hauling operations the width of a streak created by a mule foot track was measured at 10 m intervals. To compare increased average bulk density between alternatives one way The ANOVA, Duncan test and Dunnett t-test with a 95 % confidence level were used. A General linear model was applied to relate the increasing bulk density and the slope gradient. To realize the correlation between the increment of soil bulk density and the slope gradient and the correlation between the soil compaction and soil moisture content (%) The Pearson correlation test was applied. To choose the best alternative (in manual method) a MA test was applied again. The bulk density on the skidding trail increased 51 % for 30 skidding turn, 35 % for 31 skidding turn (one unloaded and one loaded pass) and 46% for 41 skidding turn. Results of ANOVA (p < 0.05) show significant differences of bulk density between alternatives. Duncan test and the Dunnett t-test indicated that the increasing soil bulk density was not significant between control samples and winching strip of TLM and extraction by mule samples. The general linear modeling and Pearson correlation test results indicated that the slope gradient had an insignificant effect on soil compaction, whilst the Pearson test indicates a medium negative correlation between soil compaction and percentage of soil moisture. By ground-based winching operation 0.07%, 0.03%, 0.05% and 0.002% of the total area and by ground based skidding operation 1.21%, 1.67%, 0.81% and 0.00% of total area was disturbed and compacted in TLM, LLM, SLM and mule. The Pearson correlation results show that the width of disturbed area was significantly influenced by the diameter of logs and length of logs (p ˂ 0.05), but there is no significant correlation between soil disturbance width and slope. The results of analysis of MA showed that soil compaction was not related to logging method but sensitivity analysis of MA shows that LLM and TLM are both preferable to SLM.
129

Modeling, Analysis, and Efficient Resource Allocation in Cyber-Physical Systems and Critical Infrastructure Networks

January 2016 (has links)
abstract: The critical infrastructures of the nation are a large and complex network of human, physical and cyber-physical systems. In recent times, it has become increasingly apparent that individual critical infrastructures, such as the power and communication networks, do not operate in isolation, but instead are part of a complex interdependent ecosystem where a failure involving a small set of network entities can trigger a cascading event resulting in the failure of a much larger set of entities through the failure propagation process. Recognizing the need for a deeper understanding of the interdependent relationships between such critical infrastructures, several models have been proposed and analyzed in the last few years. However, most of these models are over-simplified and fail to capture the complex interdependencies that may exist between critical infrastructures. To overcome the limitations of existing models, this dissertation presents a new model -- the Implicative Interdependency Model (IIM) that is able to capture such complex interdependency relations. As the potential for a failure cascade in critical interdependent networks poses several risks that can jeopardize the nation, this dissertation explores relevant research problems in the interdependent power and communication networks using the proposed IIM and lays the foundations for further study using this model. Apart from exploring problems in interdependent critical infrastructures, this dissertation also explores resource allocation techniques for environments enabled with cyber-physical systems. Specifically, the problem of efficient path planning for data collection using mobile cyber-physical systems is explored. Two such environments are considered: a Radio-Frequency IDentification (RFID) environment with mobile “Tags” and “Readers”, and a sensor data collection environment where both the sensors and the data mules (data collectors) are mobile. Finally, from an applied research perspective, this dissertation presents Raptor, an advanced network planning and management tool for mitigating the impact of spatially correlated, or region based faults on infrastructure networks. Raptor consolidates a wide range of studies conducted in the last few years on region based faults, and provides an interface for network planners, designers and operators to use the results of these studies for designing robust and resilient networks in the presence of spatially correlated faults. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2016
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Odocoileus hemionus (hemionus) on the North Rim of the Grand Canyon: A Study of Wildlife Nutrition, Metabolic Response and Interaction of the Herd with the Winter Habitat on the North Kaibab Plateau.

January 2014 (has links)
abstract: A mule deer herd exists on the northern rim of the Grand Canyon, located on the North Kaibab Plateau. Historical references to this indigenous mule deer herd presented reports of periodic population irruption and collapse. Partially funded by the Arizona Game and Fish Department and the Arizona Deer Association, examination of herd nutritional and metabolic status from the Fall 2005 - Spring 2008 was completed at the request of AzGFD and ADA. Habitat analysis included forage micro-histological, protein, and caloric content plus whole blood and plasma assays gauging herd metabolic response. Modelling was completed using best management practices wildlife energy demand calculations and principal component analysis. Forage quality analysis and modelling suggest a sufficient amount of nitrogen (N) available (DPI) to the deer for protein synthesis. Energy analysis (MEI) of forage suggest caloric deficiencies are widely prevalent on the north Kaibab plateau. Principal component analysis integrates forage and metabolic results providing a linear regression model describing the dynamics of forage utilization, energy availability, and forage nitrogen supply with metabolic demand and response of the mule deer herd. Most of the plasma and blood metabolic indicators suggest baseline values for the North Kaibab mule deer. Albumin values are in agreement with albumin values for mule deer in the Southwest. I suggest that the agreed values become a standard for mule deer in the Southwestern U.S. As excess dietary N is converted to a caloric resource, a continual state of under-nutrition exists for the deer upon entering the N. Kaibab winter range. The population is exceeding the nutritional resource plane that the winter habitat provides. Management recommendations include implementation of multiple small-scale habitat rehabilitation efforts over time, including invasive juniper (Juniperous osteosperma) and piñon (Pinus edulis) management, prescribed burning to control big sage (Artemesia tridentata) populations, and reseeding treated areas with a seed mix of native shrubs, grasses and forbs. I recommended that the population size of the North Kaibab deer herd is maintained at the current size with natural selection controlling growth, or the population be artificially reduced through increased hunting opportunities. / Dissertation/Thesis / Ph.D. Environmental Design and Planning 2014

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