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Analysis of vascular response to systemic heating using the pallid bat wingMendez, Tanya 15 May 2009 (has links)
The objective of this research is to analyze the relationship between environ-mental heat exchange and vascular response in the pallid bat wing during systemicheating and to develop a simplied model of heat transfer for theoretical analysis.During heating experiments, metabolic activity, body temperature and alterations invessel diameter and blood ow were monitored. This research is very signicant, asit will correlate thermoregulation and vascular response in a way that has not beenstudied before.The wing of the pallid bat is selected because the microvascular bed performssimilar functions as that of the human skin in terms of thermoregulation; understand-ing vascular response to heat or cold allows to analyze vascular function, or arterialhealth, a response that is altered at early stages of several diseases in humans. Athigh body temperatures, bats can dissipate heat through their wings; the bat wingserves as a thermal window where heat exchange is determined by local blood owand vascular response in the wing.For this study, a lumped mathematical model to calculate body and skin tem-perature alterations in response to changes in environmental conditions has beendeveloped. In order to formulate this model, experiments have been proposed wherethe pallid bat is subjected to dynamic systemic heating with and without the wingextended. By having the wing extended outside a metabolic chamber during heating,the bats were able to maintain an equilibrated body temperature; having the wing enclosed caused body temperature to increase rapidly. The experiments were designedto obtain correlations between systemic and vascular responses and therefore learnabout the thermoregulatory mechanisms of the pallid bat.Results from experiments following Animal Use Protocols 2006-253 and 2007-110indicate that vascular responses to environmental temperature changes (changes inTchamber) maintain or reduce body temperature to basal conditions. Vessel diameter,centerline velocity, blood ow and heat ux increase with Tchamber therefore deliveringa greater volume of blood to the bat wing and increasing heat exchange with theenvironment. The positive responses in the wing to Tchamber signify that the pallidbat is regulating its body temperature as had been expected.
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The Influence of Support Conditions on Hit Speed in BaseballDillard, Jeffrey Stephen 10 May 2003 (has links)
This paper is an investigation into the effect of the bat support conditions on the collision between a baseball and a baseball bat. Bat performance is tested using both machines and human subjects. For the machine tests, a baseball is fired from an air-cannon at a stationary bat, where the bat is either allowed to rotate only or is completely unrestricted after impact. The initial and rebound ball speeds are measured for a range of impact locations. For the human tests, a person swings the bat and hits the ball off of a tee. The bat speed prior to impact and the ball speed after impact are measured. The results for each method of testing are compared, and the final ball speed is found to be independent of the bat support condition.
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Behavior of Migratory Tree Bats in the Western Basin of Lake Erie Using Telemetry and Stable Isotope AnalysisHatch, Shaylyn K. January 2015 (has links)
No description available.
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Bat Resource Utilization Along the Potomac River Corridor in MarylandLitterer, Amber Starr 15 April 2024 (has links)
In 2021, 17-year periodical cicadas (Magicicada spp.) in Brood X emerged throughout much of the eastern United States. Due to their abundance and lack of predator avoidance during their short six-week period on the above-ground landscape, many species of animals consume cicadas and in turn have short-term habitat use and population responses. The response of bats to periodical cicadas is largely unknown. Using a before-after-control-impact study design, we deployed ultrasonic acoustic detectors during the summers of 2020–2022 within and just outside the range of the cicada emergence along the Potomac River corridor of Maryland and Virginia. For total bat activity, there was significantly more acoustic activity within the range of the cicada emergence the year during and the year following emergence than where emergence did not occur. Additionally, for all individual species and phonic groups, bat activity increased the year during and year after the emergence within the range of periodical cicadas compared to the year prior to emergence. Our study demonstrates that periodical cicadas may serve as a resource pulse that can cause an increase in bat activity and suggests at least a short-term local to regional population increase from immigration the year during and from recruitment the year following.
Bats of the mid-Atlantic have been negatively affected by numerous stressors including white-nose syndrome, wind turbine development, and land use change. One species suffering widespread population decline over the last decade in the mid-Atlantic has been the little brown bat (Myotis lucifugus). Understanding the space use and resource selection of remaining populations is critical for management and species recovery. Nevertheless, there are difficulties with studying the movement of insectivorous bats due to their small size and high vagility. Traditional foraging studies of Myotis spp. have used fixed station telemetry and associated multi-azimuthal observations to estimate the location of individuals. However, single azimuth observations are often unable to be included in these studies leading to more potential location estimates missing from movement models. During the summer of 2022, I radio-tagged little brown bats from a maternity colony along the Potomac River in Maryland and collected bearings on nine individuals using fixed station telemetry from sunset until bats returned to the maternity roost. Location estimates were obtained from both single and multi-azimuthal observations. I fit movement models for each individual and used auto-correlated kernel density estimation (AKDE) to estimate space use. I also assessed second and third order habitat selection of individual bats. The average 95% AKDE for males was 889 ha ± 424.6 and 699.3 ha ± 129 for adult females. I found bats had higher predicted use of habitat that was closer in distance to water and wetlands and further from open habitat at the second order and closer to water and open habitat at the third order of resource selection. Habitat associations were similar to previous little brown bat resource selection studies. However, estimates of space use were larger than those using other movement models. This study was novel in that it incorporated single azimuth observations and periodicity into models of space use, thereby increasing sample size and offering a new framework for future telemetry studies. These estimates of space use can be used by land managers to protect the habitat of this imperiled species. / Master of Science / In 2021, 17-year periodical cicadas (Magicicada spp.) in Brood X emerged throughout much of the eastern United States in high abundance. As an abundant food resource, many animals consume periodical cicadas while they are above ground during the summers. This has allowed for short-term population increases and changes in reproduction in some species. However, the response of bats to periodical cicadas is largely unknown. To study this, I deployed ultrasonic acoustic detectors that recorded six species/species groups of bats during the summers of 2020–2022 within and just outside the range of the cicada emergence along the Potomac River Corridor, Maryland, and Virginia. I observed significantly more total bat acoustic activity within the range of the cicada during the emergence year and the year following than where emergence did not occur. Also, for all individual species and species groups, bat activity increased in the year during and after the emergence within the range of periodical cicadas compared to the year before emergence. My study demonstrates that periodical cicadas cause an increase in bat activity and may suggest a population increase in the areas where the emergence has occurred.
Bats of the mid-Atlantic have experienced population declines due to numerous stressors including white-nose syndrome caused by the fungus Pseudogymnoascus destructans, wind turbine development, and habitat fragmentation. One species that has been heavily affected by white-nose syndrome is the little brown bat (Myotis lucifugus). To help conserve the species, understanding their home range and their resource needs is critical. However, little brown bats are small and agile fliers which poses difficulties for tracking them. Traditional foraging studies of species in this genus have used telemetry to obtain triangulations and location estimates of individuals but often leave out data collected from a single bearing as it is difficult to calculate the true location of the animal. During the summer of 2022, I radio-tagged little brown bats from a maternity colony along the Potomac River in Maryland and collected bearings on nine individuals using fixed station telemetry from sunset until bats returned to the maternity roost. We estimated locations from both triangulations and single bearings. I calculated movement models for each individual and fit them to an auto-correlated kernel density estimator (AKDE) of space use. The average 95% auto-correlated kernel density estimates of space use (AKDE) for males was 889 ha ± 424.6 and 699.3 ha ± 129 for adult females. I also assessed the habitat selection of individuals within their home range and across the nearby landscape. I found that bats preferred to use areas closer to water and wetlands and preferred to use areas closer to open habitat within their home range but preferred to use areas further from open habitat across the landscape. Habitat associations were similar to previous little brown bat resource selection studies. However, estimates of space use were larger than those using other movement models. My study was novel in that it incorporated single azimuth observations and periodicity into models of space use, thereby increasing sample size and offering a new framework for future telemetry studies. These estimates of space use can be used by land managers to protect the habitat of this imperiled species.
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Diversidade de parasitas do gênero Trypanosoma em morcegos capturados na área de influência da UHE Belo Monte - Altamira/Pará / Diversity of parasites of Trypanosoma genus in bats captured in the area of influence of hydroeletric of Belo Monte - Altamira/ParáLeite, Beatriz Helena Santos 10 September 2015 (has links)
O gênero Trypanosoma compreende flagelados capazes de infectar várias espécies de mamíferos e é transmitida por vários grupos de invertebrados. A ordem Chiroptera pode ser infectada pelos subgêneros Herpetosoma, Schizotrypanum, Megatrypanum e Trypanozoon. Neste estudo, foi possível descrever a diversidade de tripanossomas de morcegos, inferindo as relações filogenéticas entre os tripanossomas e os morcegos capturados na área de influência da Hidrelétrica de Belo Monte, localizada na Amazônia Brasileira. Tripanossomas de morcegos foram isolados por hemocultura, e a filogenia molecular foi baseada na subunidade menor do gene ribossômico (SSU rDNA) e de glicosomal-3-fosfato desidrogenase (gGAPDH). A caracterização morfológica incluiu microscopia eletrônica de luz e de varredura. Além das espécies já descritas, T. cruzi e T. cruzi marinkellei, foi possível identificar uma espécie não classificada, Trypanosoma sp., identificado em um morcego da espécie Pteronotus parnellii. Árvores filogenéticas usando combinado SSU rDNA e conjuntos de dados em cluster gGAPDH, confirmaram que esta espécie de tripanossoma de morcego, era muito divergente de outras espécies de tripanossomas. Através do posicionamento filogenético, foi possível classificar os tripanossomas deste morcego como uma espécie não classificada. Os tripanossomas isolados de morcegos na área de influência da Hidrelétrica de Belo Monte foram identificados através de análise filogenética como T. cruzi marinkellei, T. cruzi (TCI e TCbat) e em Pteronotus parnellii uma espécie não classificada e posicionada no Clado T. cruzi. Os dados obtidos neste estudo atentam para a diversidade subestimada de parasitas que infectam morcegos nos diferentes biomas brasileiros / The Trypanosoma comprises flagellates able to infect several mammalian species and is transmitted by several groups of invertebrates. The order Chiroptera can be infected by the subgenera Herpetosoma, Schizotrypanum, Megatrypanum and Trypanozoon. In this study, we described the diversity of bats trypanosomes, inferring the phylogenetic relationships among the trypanosomes from bats caught Belo Monte Hydroeletric area (Brazilian Amazonia). Trypanosomes from bats were isolated by haemoculture, and the molecular phylogeny based on small subunit rDNA (SSU rDNA) and glycosomal-3-phosphate dehydrogenase (gGAPDH) gene sequences. Morphological characterization included light and scanning electron microscopy. Besides the species already described, T. cruzi and T. cruzi marinkellei, were identify an unclassified species, Trypanosoma sp., identify into a bat species Pteronotus parnelliii. Phylogenetic trees using combined SSU rDNA and gGAPDH data sets clustered the trypanosomes of bats, which were highly divergent from other trypanosome species. The phylogenetic position made it possible to classify the trypanosomes from bats as a separate species. The bat trypanosomes isolates in Belo Monte Hydroeletric area were identified by phylogenetic analysis like as T. cruzi marinkellei, T. cruzi (TCI and TCbat) and into a bat species Pteronotus parnellii was identified a species unclassified. The diversity of bat trypanosomes in Brazil is underestimated and new studies should be conducted in brazilian biomes
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Filogeografia intraespecífica do morcego hematófago Desmodus rotundus (Chiroptera, Phyllostomidade) / Phylogeography and systematics of vampire bat Desmodus rotundus (Chiroptera; Phyllostomidae)Martins, Felipe de Mello 26 August 2008 (has links)
O morcego Desmodus rotundus é uma das três espécies de morcegos hematófagos existentes. Possui ampla distribuição, ocorrendo do sul do México até Argentina e Chile. Além de seu hábito alimentar incomum, esta espécie possui particular interesse por ser transmissor da raiva bovina. Apesar dos métodos de controle da população, estudos estimaram em até 33 milhões de dólares ao ano os prejuízos causados por esta espécie a pecuária no Brasil. Ao mesmo tempo, segundo dados oficiais, cerca de 200.000 indivíduos da espécie podem ter sido mortos no Estado de São Paulo no ano de 2000 através dos métodos de controle populacional. Além deste controle não surtir o efeito desejado (o número de casos de raiva não diminuiu no período), não se conhece qual o efeito desta matança nas populações naturais do morcego. Apesar de sua ampla distribuição e reconhecida variação morfológica, nenhum estudo foi realizado para procurar entender como a variabilidade genética desta espécie está distribuída geograficamente. Este estudo se propôs a estudar a filogeografia do morcego vampiro comum analisando um marcador mitocondrial, dois marcadores nucleares e morfometria de crânio. O marcador mitocondrial identificou cinco clados monofiléticos sem haplótipos compartilhados nem zonas de contato, cada um representando uma região geográfica diferente. São eles: Mata Atlântica sul (MAS), Mata Atlântica norte (MAN), Amazônia e Cerrado (AMC), América Central (AC) e Pantanal (PAN), sendo que os clados da Mata Atlântica formam um clado monofilético a Leste, se contrapondo aos demais clados a Oeste. Os índices de divergência entre estes clados são comparáveis a distâncias descritas para espécies congenéricas. Os tempos de divergência estimados entre os clados através de métodos coalescentes e não-coalescentes apontam para uma divergência pleistocênica, além de testes de neutralidade apoiarem a idéia de fragmentação por refúgios. O padrão biogeográfico descrito para D. rotundus possui um paralelo em uma série de outros organismos. Os marcadores nucleares por sua vez mostraram baixa variabilidade, e extenso compartilhamento de haplótipos entre as localidades pertencentes a distintos clados mitocondriais, num padrão que contrasta com os resultados descritos anteriormente. Simulações coalescentes foram realizadas com os parâmetros calculados para o gene nuclear RAG2 e mostraram compatibilidade entre os dados observados e vicariância pleistocênica para um marcador nuclear com o Ne calculados para D. rotundus. Os dados de morfometria de crânio mostraram que existe pouca diferenciação ao longo de toda a distribuição da espécie. Dados de Fst, funções discriminantes e variáveis canônicas mostram uma grande afinidade entre indivíduos dos clados AC e AMC, que juntos formam a distribuição de uma antiga subespécie atribuída a este táxon, Desmodus rotundus murinus. As análises de distância de Mahalanobis também são concordantes com os resultados obtido para o marcador mitondrial. Por fim, uma análise realizada com o software treescan mostra existir uma correlação estatisticamente significativa entre a árvore de DNA mitocondrial e os dados multivariados de crânio. Assim, por fim propõe-se que se reconheçam duas linhagens hoje atribuídas a D. rotundus como espécies distintas: uma a Leste (Mata Atlântica) e uma a Oeste. Uma amostragem mais cuidadosa do interior do Brasil e do restante da América do Sul deve determinar corretamente a área de ocorrência de cada espécie. / The bat Desmodus rotundus is one of the three extant vampire bat species. It has a broad distribution, occurring from southern México until Argentina and Chile. Besides its unique feeding habit, this species is of particular interest for being the main vector of cattle rabies. Even with population control methods, studies have estimated in 33 million dollars per year the damage caused by this bat to cattle farming in Brazil. At the same time 200.000 specimens might have been killed in São Paulo state in the year 2000 using the population control methods. Besides the fact that this control did not diminish the number of rabies cases, the impact of this killing in the bats\' natural populations is unknown. Although this species has a broad distribution and recognized morphological variation, no effort was made thus far to understand how this species\' genetic variability is distributed geographically. This work is aimed at studying the common vapire bats\' phylogeographic pattern using a mitochondrial marker, two nuclear markers and skull morphometrics. The mitochondrial marker identified five monophiletic clades without shared haplotypes or contact zones. Each clade represents a distinct geographic region: South Atlantic Forest (SAF), North Atlantic Forest (NAF), Amazon and Cerrado (AMC), Central America (CA) and Pantanal (PAN). The Atlantic Forest clades form an Eastern monophiletic clade opposing the other clade that lies westwards. The nucleotide divergence between these clades is similar to the one described to congeneric species. The divergence times estimated by coalescent and non-coalescent methods point to a Pleistocene vicariant event. The neutrality tests also point to refugia allopatric fragmentation. The biogegraphic pattern described for D. rotundus has a parallel in many other organisms. The nuclear markers showed low variability and sharing of haplotypes among all localities, contrasting with the previous results. Coalescent simulations were carried with populational parameters estimated for the nuclear gene RAG2 and showed compatibility between the observed data and Pleistocene vicariance effect on a neutral nuclear marker. Skull morphometrics showed low differentiation throughout the bats\' distribution. Data on Fst, discriminant functions and canonic variables shows affinity between CA and AMC clades. These two clades together form the distribution of a subspecies previously described to this taxon, Desmodus rotundus murinus. The Mahalanobis distance analyses are also congruent with the results obtained withn the nuclear marker. The analysis done with the software treescan shows a statistic significant correlation between the mtDNA tree and the skull multivariate data. On the basis of the results presented, it is proposed that two lineages currently atributed to D. rotundus are to be recognized as different species: one to the east (Atlantic Forest) and one to the west. A detailed sampling of the Brazilian and South American country will determine the exact range of each species.
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Diversidade de parasitas do gênero Trypanosoma em morcegos capturados na área de influência da UHE Belo Monte - Altamira/Pará / Diversity of parasites of Trypanosoma genus in bats captured in the area of influence of hydroeletric of Belo Monte - Altamira/ParáBeatriz Helena Santos Leite 10 September 2015 (has links)
O gênero Trypanosoma compreende flagelados capazes de infectar várias espécies de mamíferos e é transmitida por vários grupos de invertebrados. A ordem Chiroptera pode ser infectada pelos subgêneros Herpetosoma, Schizotrypanum, Megatrypanum e Trypanozoon. Neste estudo, foi possível descrever a diversidade de tripanossomas de morcegos, inferindo as relações filogenéticas entre os tripanossomas e os morcegos capturados na área de influência da Hidrelétrica de Belo Monte, localizada na Amazônia Brasileira. Tripanossomas de morcegos foram isolados por hemocultura, e a filogenia molecular foi baseada na subunidade menor do gene ribossômico (SSU rDNA) e de glicosomal-3-fosfato desidrogenase (gGAPDH). A caracterização morfológica incluiu microscopia eletrônica de luz e de varredura. Além das espécies já descritas, T. cruzi e T. cruzi marinkellei, foi possível identificar uma espécie não classificada, Trypanosoma sp., identificado em um morcego da espécie Pteronotus parnellii. Árvores filogenéticas usando combinado SSU rDNA e conjuntos de dados em cluster gGAPDH, confirmaram que esta espécie de tripanossoma de morcego, era muito divergente de outras espécies de tripanossomas. Através do posicionamento filogenético, foi possível classificar os tripanossomas deste morcego como uma espécie não classificada. Os tripanossomas isolados de morcegos na área de influência da Hidrelétrica de Belo Monte foram identificados através de análise filogenética como T. cruzi marinkellei, T. cruzi (TCI e TCbat) e em Pteronotus parnellii uma espécie não classificada e posicionada no Clado T. cruzi. Os dados obtidos neste estudo atentam para a diversidade subestimada de parasitas que infectam morcegos nos diferentes biomas brasileiros / The Trypanosoma comprises flagellates able to infect several mammalian species and is transmitted by several groups of invertebrates. The order Chiroptera can be infected by the subgenera Herpetosoma, Schizotrypanum, Megatrypanum and Trypanozoon. In this study, we described the diversity of bats trypanosomes, inferring the phylogenetic relationships among the trypanosomes from bats caught Belo Monte Hydroeletric area (Brazilian Amazonia). Trypanosomes from bats were isolated by haemoculture, and the molecular phylogeny based on small subunit rDNA (SSU rDNA) and glycosomal-3-phosphate dehydrogenase (gGAPDH) gene sequences. Morphological characterization included light and scanning electron microscopy. Besides the species already described, T. cruzi and T. cruzi marinkellei, were identify an unclassified species, Trypanosoma sp., identify into a bat species Pteronotus parnelliii. Phylogenetic trees using combined SSU rDNA and gGAPDH data sets clustered the trypanosomes of bats, which were highly divergent from other trypanosome species. The phylogenetic position made it possible to classify the trypanosomes from bats as a separate species. The bat trypanosomes isolates in Belo Monte Hydroeletric area were identified by phylogenetic analysis like as T. cruzi marinkellei, T. cruzi (TCI and TCbat) and into a bat species Pteronotus parnellii was identified a species unclassified. The diversity of bat trypanosomes in Brazil is underestimated and new studies should be conducted in brazilian biomes
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A Historical Perspective and Review of the Evidence to Support Fruit Bats as the Natural Reservoir for Ebola VirusesReed, Zachary 20 December 2012 (has links)
The Ebola viruses cause sporadic outbreaks of Ebola hemorrhagic fever (EHF) where origins have been traced to the continent of Africa and the Philippines. Since the initial discovery of Zaire and Sudan ebolavirus in 1976, the Ebola viruses have been responsible for severe hemorrhagic fever outbreaks in Africa with case fatality rates between 40-90%. The natural reservoir(s) of the Ebola viruses is currently unknown, but there is mounting evidence that fruit bats may play a key role. The goal of the current study is to screen a large variety of bat species from Africa and Asia where Ebola is known to be endemic for the presence of IgG specific antibody to Ebola virus in order to see which bat species may show evidence of past Ebola virus infection. Ebola virus would not be expected to cause lethal disease in its natural reservoir; therefore the presence of IgG antibody would be present. Identifying the species of bats that have been infected will allow researchers to hopefully isolate Ebola virus from bats adding to the evidence that bats are a reservoir species. The knowledge gained may also provide clues to new species of bats yet to be identified as possible natural reservoir(s) as well as expand the known geographical range of known Ebola virus outbreaks. Knowing which species of bats as well as their geographic range may help prevent future Ebola outbreaks by minimizing human-reservoir contact.
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Kroppsuppfattning hos unga kvinnor : En enkätstudie av kvinnor mellan 18 och 25 år på Linneuniversitetet i VäxjöLarsson, Marit, Jönsson, Pamela January 2011 (has links)
No description available.
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Integration of microvascular, interstitial, and lymphatic function to determine the effect of their interaction on interstitial fluid volumeDongaonkar, Ranjeet Manohar 15 May 2009 (has links)
Although the physics of interstitial fluid balance is relatively well understood,
clinical options for the treatment of edema, the accumulation of fluid in the interstitium,
are limited. Two related reasons for this failure can be identified. First, the processes
involved in the transfer of fluid and proteins into the interstitium from the
microvasculature, and their transfer out of the interstitium via the lymphatic system, are
governed by complex equations that are not amenable to manipulation by physiologists.
Second, the fundamental processes involved include complex anatomical structures that
are not amenable to characterization by engineers. The dual tools of the batwing model
and simplified mathematical modeling can be used to address the main objective: to
integrate microvascular, interstitial, and lymphatic function to determine the effect of
their interaction on interstitial fluid volume. In order to address this objective and the
limitations of the current state of knowledge of the field, three specific aims were
achieved. 1) Develop a simple, transparent, and general algebraic approach that predicts interstitial fluid pressure, volume and protein concentration resulting from the interaction
of microvascular, interstitial and lymphatic function. These algebraic solutions provide a
novel characterization of interstitial fluid pressure as a balance point between the two
processes that determine interstitial inflow and outflow. 2) Develop a simple, algebraic
formulation of Edemagenic Gain (the change in interstitial fluid volume resulting from
changes in effective microvascular driving pressure) in terms of microvascular,
interstitial and lymphatic structural parameters. By separating the structural parameters
from functional variables, this novel approach indicates how these critical parameters
interact to determine the tendency to form edema. 3) To expand the list of known
interactions of microvascular, interstitial, and lymphatic functions to include the direct
interaction of venular and lymphatic function. Venomotion was found not only to
extrinsically pump lymph but also to mechanically trigger intrinsic lymphatic
contractions. These three advances together represent a new direction in the field of
interstitial fluid balance, and could only be possible by taking an interdisciplinary
approach integrating physiology and engineering.
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