Rozprawy doktorskie: „Heartwood”

1

Bergström, Berit. "Aspects on heartwood formation in Scots pine /". Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5863-3.pdf.

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McGinley, Susan. "Broken Branches: Brown Heartwood Rot of Citrus". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/622308.

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Boakye-Yiadom, Kaleem. "Selected anatomical, extractive and physical wood properties of Cylicodiscus gabunensis (Harm) : a tropical timber species /". free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3036806.

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4

Kennedy, Michael James. "Natural and enhanced wood durability from pine heartwood phenolics". Thesis, Queensland University of Technology, 1996. https://eprints.qut.edu.au/107122/1/z%20T%28S%29%20108%20Natural%20and%20enhanced%20wood%20durability%20fro%20pine%20heartwood%20phenolics.pdf.

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Wood is a naturally occurring, complex, structured, polymeric material comprised of a structural matrix in which are embedded a vast variety of extractible compounds. The organic carbon-rich matrix is susceptible to biodeterioration by a wide range of bacterial, fungal, insect and other organisms, despite protective effects of the extractives. Wood preservatives developed over the past 50 years have provided efficient ways of preventing biodeterioration, but many of them are under threat from an increasingly chemophobic populace. Naturally bioactive wood extractives offer promise of control of many wood destroying organisms, and may be more acceptable than these more powerful synthetic biocides. Phenolic compounds, relatively abundant extractives from the heartwood of Pinus spp., plantation-grown worldwide, were evaluated for bioactivity. Heartwood from Pinus spp. containing elevated phenolic concentrations was more resistant to subterranean termites than that from species characterized by low phenolics. While the stilbene phenolics were poorly related to resistance, the flavonoid phenolics appeared to be more closely associated with resistance. However, unspecified additional heartwood compounds contributed strongly to termite resistance. Both Pinus el/iottii and Pinus caribaea, previously classed with Pinus radiata as susceptible to termite attack, were naturally resistant to two significant Australian termite species. Acceptance of this resistance has enabled previous limitations on unpenetrated heartwood in these spp. to be removed from Australian requirements for preservative treatment against termites, with consequent economic benefit to the preservative treatment industry and consumers.

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5

Gustafsson, Gabriella. "Heartwood and lightwood formation in Scots pine : a physiological approach /". Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6077-8.pdf.

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6

Beauchamp, Kate. "Biology of heartwood formation in Sitka spruce and Scots pine". Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5788.

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Heartwood is the dead, inner layers of wood in the tree which no longer transport water. It is usually dark in colour and has increased decay-resistance compared to the sapwood. Heartwood forms in the transition zone when the ray cells die and deposit chemical extractives in the surrounding xylem. These chemicals convey natural durability which is of value to the forest and timber industry. Despite its value the formation of heartwood is poorly understood. The objective of this PhD is to improve our understanding of heartwood formation in Sitka spruce and Scots pine, the most widely planted species in Britain. Separating heartwood and sapwood at the sawmill can increase timber value due to differences in wood properties. The amount of heartwood varies both with height within, and between trees. Empirical models were developed to describe heartwood and sapwood distribution by diameter, area and ring number 1) within any wood disc 2) with height in the standing tree using taper functions, and 3) its variation between trees. Models will be incorporated into wood quality models to optimise heartwood utilisation. According to pipe theory a certain area of sapwood sustains a volume of canopy, with redundant sapwood converted to heartwood. Sap flux was examined across the sapwood and transition zone in Sitka spruce to understand water transport in relation to heartwood formation and identify seasonal change in transport in the transition zone. Results suggest that the transition zone ceases water transport around dormancy and the amount of heartwood formed may be driven by new wood formation, maintaining sapwood depth. Heartwood formation is a seasonal process, however this has not been confirmed in Sitka spruce or Scots pine, or under UK climatic conditions. Seasonal variation in carbon dioxide and ethylene production by the transition zone were measured to identify the time of heartwood formation, which was late summer through dormancy, consistent with published literature. The role of ethylene in heartwood formation is confirmed. Heartwood formation is an active developmental process, a form of programmed cell death, and as such must be carefully regulated temporally and spatially. Regulation by phytohormones has been proposed but not confirmed. Screening for a broad range of phytohormones during the proposed season of heartwood formation identified an increase in abscisic acid and a decrease in auxin concentration in the transition zone. Abscisic acid, auxin and ethylene also regulate xylogenesis, therefore the same signals that initiate cambial dormancy may also provide the temporal regulation of heartwood formation. The results of this PhD will optimise the use of heartwood in Sitka spruce and Scots pine in the UK and contribute towards selective tree breeding for increased heartwood volume worldwide.

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7

Zhang, Chunhua. "Three-dimensional cell arrangement and heartwood substances movement in hardwoods". Kyoto University, 2004. http://hdl.handle.net/2433/145415.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第11070号
農博第1435号
新制||農||896(附属図書館)
学位論文||H16||N3951(農学部図書室)
22602
UT51-2004-J742
京都大学大学院農学研究科森林科学専攻
(主査)教授藤田稔, 教授伊東隆夫, 教授野渕正
学位規則第4条第1項該当

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Kemp, Joshua M. "Heartwood: Spiritual homebuilding and white-vanishing in Australian gothic fiction". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2022. https://ro.ecu.edu.au/theses/2549.

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This thesis represents the spiritual connection between a non-Aboriginal Australian and the Australian natural landscape through a creative work, Heartwood, and an exegesis, which engages with the white-vanishing trope in Australian Gothic fiction. It critically examines ways in which this trope has been used in Australian literature to, consciously or not, represent Aboriginal characters as Other, peripheral or absent, and sometimes appropriated their religious beliefs. Heartwood (2021) is an Australian Gothic novel which features two white Australian characters and their spiritual connection to the landscape, in an attempt to articulate the white-vanishing trope but without othering or sidelining Aboriginal characters. The novel also attempts to explore a form of spiritual connection which does not impinge on or appropriate Aboriginal religious beliefs, a thematic concept rarely explored in Australian Gothic fiction. This thesis utilised the Practice Based Research methodological approach in an attempt to gain new knowledge through the research and creative production of a novel, Heartwood. The subsequent exegesis explores how effective this creative work has been in seeking out this new knowledge. Since the emergence of Australian forms of Gothic fiction during colonisation, white Australian writers have explored the complex and fraught spiritual relationship between non-Aboriginal people and the landscape, often utilising corrosive narrative structures such as the lost-in-the-bush trope to do so. In these texts Aboriginal presence is sidelined or even completely ignored in favour of a primarily white Australian focus. When Aboriginal characters do appear, they have been depicted as demonic, ghostly or supernatural. Some academics believe because Aboriginal characters are depicted as inhuman, their connection to the landscape and sense of land ownership has been elided. Aboriginal religious beliefs have also been appropriated in these works to explore a non- Aboriginal sense of spirituality. Some of the most popular and critically acclaimed Australian novels of the twentieth century have been guilty of this, such as Voss by Patrick White and Picnic at Hanging Rock by Joan Lindsay. This creative work, and the exegesis accompanying it, explore and ultimately seek to subvert the bias inherent in these traditions of Australian Gothic fiction. This is achieved by producing a story which refuses to appropriate Aboriginal religious and/or spiritual beliefs, as well as featuring Aboriginal characters who are not depicted as supernatural or ghostly. The novel also explores a spiritual connection between non-Aboriginal characters and the natural landscape of Western Australia’s Southern Forests region without impinging on the religious beliefs of Aboriginal people. The creative work re-emplaces Aboriginal presence into the text without appropriating an Aboriginal voice or point-of-view.

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9

Jeremic, Dragica. "Comparative analysis of wetwood, heartwood and sapwood properties in balsam fir". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ46260.pdf.

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Lourenço, Ana Carina dos Santos. "The influence of heartwood on kraft delignification of Eucalyptus globulus wood". Doctoral thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5199.

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Sousa, Vicelina Milena Piteira Rebelo Barnabé. "Variabilidade anatómica e da densidade da madeira de Quercus faginea em diferentes idades e condições ambientais". Doctoral thesis, ISA, 2013. http://hdl.handle.net/10400.5/6969.

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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
The importance and valorization of the species that occur naturally in Portugal motivated the present study to evaluate the properties, variability and the technological potential of the wood of Quercus faginea Lam., commonly referred as Portuguese or Lusitanian oak. Growth rings, heartwood development, anatomical characteristics of wood and bark and wood density were studied at different ages and sites. The wood showed growth ring porosity, high fibre and rays proportion and high wood density. The heartwood proportion was relatively high and increased from the base to the top following the trunk profile. Sapwood thickness was approximately constant. The fibre and multiseriate rays showed an increasing tendency towards the bark as well as the mean earlywood vessels area. The ring width and wood density decreased from pith to bark. The variation sources included age, trees and environmental conditions. Site was responsible for the main variations followed by tree and cambial age. The correlations between the studied variables showed that growth and wood quality might be estimated namely with ring width. The wood characterization and relative stem homogeneity allow exploitation of this species and reinforce its role in forest diversity.

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12

Matheron, Michael E., i Martin Porchas. "Studies of the Biology and Control of Brown Heartwood Rot on Lemon Trees in 2000". College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/226093.

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Brown heartwood rot is commonly found in mature lemon groves in southwestern Arizona. Two basidiomycete fungi, Antrodia sinuosa and Coniophora eremophila, have been isolated from symptomatic trees. Similarities between the two pathogens include the following: each fungus grows optimally at 30 to 35°C, neither organism produces a fleshy fruiting body, they colonize lemon trees primarily through branch fractures and other non-pruning wounds, and both cause a brown wood rot in infected trees. A major difference between the two pathogens is that Antrodia forms spore-producing fruiting bodies on infected wood within lemon groves, whereas fruiting on lemon wood infected by Coniophora has not been observed. The rate of wood decay in lemon branches inoculated with Antrodia is at least three times greater than that caused by Coniophora. Wood decay columns produced by either fungus from late spring to early autumn were at least three times larger than those that developed from late autumn to early spring. When inoculated with either pathogen, the length of wood decay columns on branches 10 mm in diameter was numerically smaller than those on branches 20 and 40 mm in diameter. Wood decay on Lisbon lemon branches inoculated with either Antrodia or Coniophora was significantly greater than that on Marsh grapefruit, Orlando tangelo, and Valencia orange. Treatment of lemon branch inoculation sites with azoxystrobin or propiconazole at 20 g of active ingredient per liter of solution reduced the resultant length of wood decay columns by 61 and 77%, respectively, for Antrodia, and 92 and 85%, respectively, for Coniophora. When selected desert plants were inoculated, Antrodia produced wood decay columns on Palo Verde, salt cedar, greasewood, and mesquite branches that were much shorter than those recorded on Lisbon lemon branches. On the other hand, Coniophora produced longer wood decay columns on salt cedar and mesquite than on Lisbon lemon, whereas wood rot on lemon was greater than that on Palo Verde and greasewood. Current disease management strategies include minimizing branch fractures and other non-pruning wounds, and periodic inspection of trees and removal of infected branches, including physical removal of all wood infected with Antrodia from the grove site.

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Bajraktari, Agron. "Wood quality of Quercus cerris from Kosovo". Doctoral thesis, ISA, 2018. http://hdl.handle.net/10400.5/15830.

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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL
Kosovo’s forest products industry is a very important part of Kosovo’s economy and within the present work data was collected through a survey of all sawmills in Kosovo and information gathering from the Ministry of Agriculture, Forestry and Rural Development of Kosovo. The forest resources and sawmill structure of Kosovo were analyzed and the availability of different species of wood in different regions of the country established. In parallel, the study of one home grown wood species, Quercus cerris, was conducted in order to improve its use in sawmilling to produce value added wood components. For this purpose, ten Quercus cerris trees, grown in two sites in Kosovo, were felled and discs taken at different stem height levels. Relevant data for this species was obtained on stem quality, including heartwood, sapwood and bark development as well as ring analysis. Chemical and durability characterization was also conducted together with the evaluation of density and Brinell hardness. Quercus cerris from Kosovo showed good potential as a timber species for the supply of stem wood to the saw-milling industry allowing good yields of heartwood-only sawn wood components. Taking into account the good technological properties measured together with the apparent low level of extracts and the low durability class against subterranean termites, interior or protected uses are highly recommended. The bark should also be considered for complementary valorization. Furthermore, based on the worked developed, a curricular programme combining scientific and technological knowledge for industrial management, communication knowledge and creative work was developed in close cooperation with wood processing enterprises in Kosovo, and with the Kosovo Wood Processing Association. Recommendations were also provided for further development of the forest and sawmill industry
N/A

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IMAI, Takanori, 貴規今井, Eriko ITO, 恵理子伊藤, Kazuhiko FUKUSHIMA i 和彦福島. "Biochemical studies of matured xylem of Cryptomeria japonica - Attempts to detect the enzymes involved in the biosyntheses of the heartwood extractives -". 名古屋大学農学部附属演習林, 2005. http://hdl.handle.net/2237/8529.

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Lehnebach, Romain. "Etude de la variabilité ontogénique du profil ligneux chez quelques espèces forestières tropicales de Guyane Française". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS021/document.

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Le bois est un tissu plurifonctionnel permettant la conduction de la sève brute, le stockage de l’eau et des sucres ainsi que le soutien mécanique de la plante. L’arbre au cours de son développement expérimente différentes contraintes liées à son environnement et à sa taille croissante. En réponse à ces contraintes, les performances fonctionnelles du bois sont ajustées par des variations de valeurs de propriétés, elles-mêmes dépendantes du produit de la xylogénèse. Cependant les extrais chimiques déposés lors du processus de duraminisation, entraine la modification des propriétés du bois. Les propriétés du duramen sont le fruit de la xylognénése et de la duraminisation ainsi que de leurs interactions. Ce travail de thèse a donné naissance au terme ‘profil ligneux’, désignant l’ensemble des variations des propriétés du bois à différentes échelles et dans une dimension ontogénique résultant des deux processus cités précédemment. La diversité de tempéraments vis-à-vis de la lumière (héliophilie à sciaphilie) des essences tropicales suggère une diversité d’expressions du profil ligneux. La description de ces différentes expressions serait gage d’une meilleure compréhension du tempérament. Comprendre et caractériser le profil ligneux et la variation de la quantité de bois de cœur dans l’arbre, représentent également un enjeu économique puisque l’industrie du bois Guyanaise a été identifiée comme une filière d’avenir. L’analyse de la diversité du profil ligneux—par une approche ascendante, de l’échelle individuelle à l’échelle interspécifique—a prouvé son efficacité dans la discrimination du degré d’affinité à la lumière. La variation de densité est particuliérment pertinente. Néanmoins, sa pertinence réside dans (1) la combinaison du gradient radial et vertical et (2) la prise en compte du duramen qui modifie parfois, l’amplitude et la direction du gradient ainsi que la forme du profil.L’effet de la duraminisation sur la variation de densité devient alors évocateur du tempérament de l’espèce au même titre que la qualité et/ou la quantité d’extraits chimique mis en jeu. La pertinence du profil ligneux dans la caractérisation du tempérament écologique est due à son aspect intégrateur de divers processus et propriétés. En regard du changement l’allocation de croissance (i.e. du tronc vers la couronne) observée chez Dicorynia guianensis et de travaux précédents sur la croissance des arbres, un lien potentiel entre la diversité du profil ligneux et la stratégie d’allocation de la croissance pourrait exister
Wood is a multifunctional tissue involved in sap conduction, storage of water and reserves as well as mechanical support. Tree during its development experiments various constraints due to its environment and its growing size. In response to these constraints, wood functional performances are adjusted by variations of property values, which are dependent on the xylogenesis product. However, wood properties may be modified by the deposition of chemical extractives during heartwood formation. Thus heartwood properties are the result of xylogenesis, heartwood formation and their interactions. This work gave rise to the term 'wood profile', designating all variations of wood properties at different scales and in an ontogenetic dimension, resulting from both processes described above. The diversity of shade tolerance (heliophilic to sciaphilic) strategies species suggests a diversity of wood profile expressions. The description of these different expressions could be a way to better understand plant strategies. Understanding and characterizing wood profile and variations in heartwood quantity in tree, is an economical issue since the Guyanese timber industry has been identified as a promising sector. The analysis of the diversity of wood profile—using a bottom-up approach, from the individual level to the interspecific level—proves to discriminate shade tolerance strategies efficiently. Wood specific gravity variation is especially relevant. However, its relevance is based on (1) combinations of both radial and vertical variations and (2) integration of heartwood that may impact range and direction of the gradient and shape of the profile as well. Effect of heartwood formation on wood specific gravity variations is suggestive of shade tolerance strategy as well as quality and/or quantity of chemical extractives. Relevant characterization of shade tolerance strategies by wood profile is the result of the integration of diverse processes and properties. To the view of growth allocation shift (from trunk to crown) observed in Dicorynia guianensis and of previous studies on tree growth, a potential link between wood profile diversity and growth allocation strategies may exist

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Pähn, Tess. "A Manifesto for Wood & the Search for Bois-brut". Thesis, KTH, Arkitektur, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-222139.

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Wood is often perceived as a flawed material. When painted, technologically treated or sealed, in a pursuit to make it more predictable and durable, some of its most important qualities are mislaid. This project explores the aesthetic, material and constructional possibilities of wood, and suggests the possibility of a wood brutalism architecture. The project includes a written manifesto for the benefits of wood in the human habitat, proposes a CO₂ based economic strategy for our built environment and promotes massive wood buildings as our carbon savings account. To find out what a wood brutalism of today might be, the project includes an analysis of the relationship between the material concrete, Betón-brut and the zeitgeist of the 60´s and 70´s. In the application of the manifesto and Bois-brut on a case study housing project in Östberga, Stockholm, the Trellick tower has acted as a brutalist mirror reference. Vernacular timber buildings have provided clues in the search for the essence of wood.

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ADU-BREDU, Stephen, Akio HAGIHARA i 秋男萩原. "Sapwood Amount and its Predictive Equations for Young Hinoki Cypress (Chamaecyparis obtusa) Trees". 名古屋大学農学部付属演習林, 1996. http://hdl.handle.net/2237/8712.

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Niamké, Florence Bobolé. "Recherche des déterminants biochimiques de la durabilité naturelle du bois de teck (Tectona grandis)". Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20046.

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La durabilité du bois de teck (Tectona grandis) est une propriété pouvant varier selon le génotype et les facteurs environnementaux. Chez le teck, le degré d'implication des extractibles dans la durabilité naturelle est controversé. A partir d'une approche quantitative incluant les aspects biologiques et technologiques conduites sur des échantillons de bois séchés à l'air ambiant, cette thèse s'est attachée à rechercher les déterminants chimiques de nature phénolique de la durabilité naturelle. Nous avons tout d'abord mis en évidence que les formes osidiques stockées dans l'aubier sont transformées en extractibles de nature quinonique. Nous avons ainsi caractérisé deux composés, l'un dans l'aubier le forsythoside B, un trisaccharide de l'acide caféique et l'autre dans le duramen, le 4',5'-dihydroxy-épiisocatalponol qui ont été identifiés pour la première fois dans le bois de teck. Nous avons mis en évidence que le second composé inhibe la croissance de Trametes versicolor indiquant son rôle directe dans la propriété de durabilité naturelle du bois de teck. Ainsi, les composés du métabolisme des naphthoquinones sont les plus impliqués dans la durabilité naturelle du bois de teck à l'égard de Trametes versicolor et de Poria placenta. Les mécanismes de transformation des sucres pourraient indiquer le niveau de durabilité naturelle des espèces. Ces nouvelles données contribueront aussi à l'amélioration de la qualité du bois qui par ailleurs assure la pérennité des arbres
Teak (Tectona grandis) wood natural durability is a property which can vary with genotype and environmental factors. The implication of quinonic extractives in the property of natural durability is controversial. Using a quantitative approach including biological and technological conducted on air-dried wood samples, this thesis aimed to search chemical attributes of natural durability. We first demonstrated that osidic forms stored in the sapwood were transformed into quinone derivative. We have characterized two compounds the forsythoside B, a trisaccharide of cafeic acid in the sapwood and in the heartwood, the 4',5'-dihydroxy(epi)isocatalponol that were identified for the first time in teakwood. The latter compound exhibited strong fungicidal activity against Trametes versicolor indicating that its direct implication in decay resistance of teak wood. We have shown that compounds from naphthoquinones metabolism were involved in decay resistance of teak wood against Trametes versicolor and Poria placenta. The mechanisms of sugars transformation may indicate the natural durability level of sustainable species. There these new data will contribute to improve the wood quality that ensures the perennity of trees

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Mehats, Jérémy. "Différence de couleur entre duramen et aubier du bois de Pin maritime : identification moléculaire, homogénéisation et évolution". Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0154.

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Le pin maritime est l’une des espèces de conifères les plus communes retrouvées dans le Sud-Ouest de la France, couvrant plus de 10% de la surface forestière totale du territoire. A ce jour, il est surtout utilisé pour son bois, qui est transformé par les industriels en produits finis de différentes qualités, allant de l’emballage (palettes) à du matériel plus technique, pour la construction par exemple. Cependant, le retour des consommateurs ainsi que les cahiers des charges des opérateurs ont permis d’identifier une problématique majeure : la différence de couleur entre le duramen et l’aubier.Cette essence possède un duramen de couleur caractéristique allant du rosé au rouge sang et un aubier ayant une teinte plus claire, jaune-beige. Cette différence est à l’origine d’inhomogénéités esthétiques qui vont dévaloriser la valeur commerciale du bois, notamment celle des produits finis techniques. Afin de palier à cette problématique, les industriels s’intéressent aux différentes méthodes existantes pour réduire cet écart de coloration.L'objectif de cette thèse est, après avoir identifié les différences de composition chimique entre duramen et aubier, de pouvoir diminuer cette différence de couleur par l'utilisation de traitements issus des procédés papetiers, en particulier ceux basés sur la chimie du peroxyde d'hydrogène
Maritime pine is one of the most common softwood found in South West of France, covering more than 10% of the total forestry area of the country. With the development of the petroleum-based chemistry, maritime pine has been mostly used for its wood that possesses some good mechanical properties, for the elaboration of materials for packaging purposes (ex: wood pallet) or engineered wood products for structural applications. Nevertheless, due to consumers’ feedbacks and to requirements specifications, the industries identified a major issue: the color difference between heartwood and sapwood.Heartwood is known to have a brown reddish color contrary to sapwood, which have a pale yellow tint. This coloration difference results in a depreciation of the commercial value of the finished material. Thus, industrials are looking for treatments to homogenize the color and to valorize all their productsThe purpose of this PhD is firstly to identify the chromophores that are responsible of this color differences between the two wood structures and then to develop an homogenisation treatment based on the paper industry processes, particularly using alkaline hydrogen peroxide chemistry

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Jones, Christopher G. "The best of Santalum album : essential oil composition, biosynthesis and genetic diversity in the Australian tropical sandalwood collection". University of Western Australia. School of Plant Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0146.

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[Truncated abstract] An investigation into the causes of heartwood and essential oil content of Australian plantation sandalwood, Santalum album was undertaken. Genetic diversity of 233 S. album, five S. austrocaledonicum and fifteen S. macgregorii trees growing in the Forest Products Commission arboretum, Kununurra WA, was assessed using nuclear and chloroplast RFLPs. Santalum spicatum was chosen as an out-group. Nuclear genetic diversity of the S. album collection was very low, with observed and expected heterozygosity levels of 0.047. This was lower than the results previously reported in the literature for trees in India, however a different technique was used. Based on allelic patterns, the collection was able to be categorised into 19 genotypes; each representing some shared genetic origin. Some groups were highly redundant with 56 trees being represented, while others were populated by just one tree. The essential oil yield and heartwood contents of trees from these genetic groups were compared. Yields were highly variable both within and between groups of trees which share a common genetic history, suggesting a significant environmental component was contributing to the observed phenotype, despite identical soil and climatic conditions. Ancestral lineages were tested using chloroplast RFLPs, although a lack of shared mutations between species made this difficult. Only one S. album tree originating from Timor was resolved using nuclear RFLPs, with the other trees being grouped with material sourced from India. There was no resolution of Indian S. album from Timorese using chloroplast RFLPs, however one S. album tree grown from Indian seed possessed a single unique mutation. The low genetic diversity of the Australian S. album collection is likely to be a combination of incomplete seed sourcing and highly restricted gene flow during the evolution of the species. Combined with information gathered on the phylogeny of the genus by other researchers, S. album is postulated to have originated from an over-sea dispersal out of northern Australia or Papua New Guinea 3 to 5 million years ago. Essential oil yield and composition was assessed for 100 S. album trees growing in the collection, ranging in age from 8 to 17 years. Oil content of heartwood ranged from 30 mg g-1 to 60 mg g-1, and the transition zone 36 mg g-1 to 90 mg g-1. Sapwood contained almost no sesquiterpene oils. Despite the highly variable total oil yields, the chemical profile of the oil did not vary, suggesting there was limited genetic diversity within this region of the genome. Strong, positive correlations existed between v sesquiterpenoids in the essential oil of S. album. ... These represent the first TPS genes to be isolated from sandalwood and will enable further elucidation of oil biosynthesis genes. This thesis compiles a three-pronged approach to understanding the underlying causes of oil yield variation in S. album. As a species for which so little is known, the research presented here provides a major leap forward for tree improvement, breeding and silviculture. Hence the best of Santalum album research is presented.

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Cardoso, Danielle de Souza. "Caracterização anatômica da madeira e potencial dendrocronológico de Schinopsis brasiliensis Eng. (Anacardiaceae) na caatinga sergipana". Universidade Federal de Sergipe, 2014. https://ri.ufs.br/handle/riufs/4423.

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The Schinopsis brasiliensis Engl. (braúna) is a long-lived species with wide distribution in phytogeographical areas of caatinga and cerrado. Due to uncontrolled exploitation of its timber and the environmental devastation of the caatinga is currently a threatened species. However, these trees have higher dimensions than other species of this environment and, therefore, have higher ecological importance. The biological and ecological characteristics of this species highlights the need of studies about theirs structures and reaction to environmental and climatic changes, among these wood anatomy and dendrochronology. The present study collected specimens of S. brasilienis from São Pedro Farm, in the municipality of Porto da Folha/SE. Living wood and construction wood samples were collected in June and July, 2013, through a non-destructive method, afterwards the samples were kept in the UFS Plant Anatomy and Dendroecology Laboratory, for sample preparations and data analisys. The heartwood and sapwood were significantly different in structure (p<0.05 for all analysis), which revealed that the structure of the heartwood is more resistant to environmental weathering, justifying its use for rural constructions in areas of caatinga. It has growth rings limited by marginal parenchyma band and/or thickness of the fiber walls; small vessels, and tyloses when in the heartwood; rays with procumbent and square cells that store many calcium oxalate crystals; and short and thick fibers. The cross-dating of growth rings series showed correlation of 0.52 between their live individuals and 0.49 among the construction wood. The chronology showed positive correlations with rainfall in the beginning and ending of the rainy season, and fall in the increase rate in the warmer and drier periods of the year, coinciding with the leaf fall and consequent disruption of metabolic activity in new xylem cells´ generation. The analysis of the rings in construction woods allowed new chronology expansion in Brazil, for the previous 20 years to the formation of the first growth ring of the older sample of S. brasiliensis.
A Schinopsis brasiliensis Engl. (braúna) é uma espécie longeva com ampla distribuição nos domínios fitogeográficos da caatinga e cerrado. Por conta da exploração sem controle de sua madeira e da devastação ambiental que assola a caatinga, encontra-se atualmente ameaçada de extinção. Porém, é uma espécie que se destaca por possuir indivíduos com dimensões superiores às geralmente encontradas em outras espécies deste ambiente, e por isso foi classificada como de alta importância ecológica. Suas características biológicas e ecológicas enfatizam a necessidade de estudos sobre suas estruturas e reações às mudanças ambientais e climáticas, dentre estes os de anatomia da madeira e dendrocronologia. O estudo foi realizado com indivíduos de S. brasiliensis provenientes da Fazenda São Pedro, município de Porto da Folha/SE. Amostras de árvores e de madeiras de construção foram coletadas nos meses de junho e julho de 2013, através de método não destrutivo, e posteriormente foram armazenadas no Laboratório de Anatomia Vegetal e Dendroecologia da UFS, para preparo e análise dos dados. A madeira de S. brasiliensis apresentou cerne e alburno significativamente distintos estruturalmente (p<0,05), houve destaque para as características estruturais que tornam o cerne a região mais resistente e duradoura, justificando seu uso em construções rurais em áreas de caatinga. Apresentou anéis de crescimento delimitados por banda de parênquima marginal e/ou espessamento das paredes das fibras; vasos pequenos, com tiloses quando no cerne; raios formados por células procumbentes e quadradas que armazenam muitos cristais de oxalato de cálcio; e fibras curtas e grossas. A espécie foi passível de datação cruzada com 0,52 de correlação entre seus indivíduos vivos e 0,49 entre as árvores e madeiras de construção. Apresentou correlações positivas com a precipitação no início e final do período chuvoso e queda na taxa de incremento nos períodos mais quentes e secos do ano, coincidindo com a queda foliar e consequente interrupção das atividades metabólicas de formação de novas células xilemáticas. A análise dos anéis das madeiras de construção permitiu a inédita expansão de uma cronologia no Brasil, com a inclusão de 20 anos de medidas anteriores à formação do primeiro anel de crescimento da árvore mais velha amostrada na área de estudo.

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Coldebella, Rodrigo. "CARACTERIZAÇÃO DAS PROPRIEDADES FÍSICAS, QUÍMICAS E ANATÔMICAS DA MADEIRA DE Maclura tinctoria (L.) D. DON EX STEUD". Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/8782.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The imminence of Panambi s dam construction, in the municipality of Alecrim, Rio Grande do Sul, affecting the municipality of Porto Mauá, which will overflow thousands of hectares of rainforest, Macluratinctoria s habitat and, the great exploitation of the specie in the region led to the initiation of this research work. The specie is commonly known as Tajuva, presents arboreal sized, and belongs to the botanical family Moraceae, native of Rio Grande do Sul. It is a semideciduous specie, with heights between 10 to 30 meters and, up to 100 cm of diameter; short trunk, with a smooth bark, grayish green with many yellowed lenticels, many times, with the presence of branched thorns. The study aimed to the realization of anatomical description, the chemical characterization and the basic and weighted densities of Maclura tinctoria(L) D. Don Ex Steud wood. The five studied exemplars were obtained through environmental license, in accordance with current legislation. Three wood samples, taken from BHD were used for the manufacture of histological slides and for the fibers quantification. To the determination of wood density and the chemical analysis of wood, disks were removed from the trunk and divided into opposing wedges. It were used opposing wedges removed from six pre-established heights (base, DAP, 25%, 50%, 75% and 100% of commercial height). It was used the ASTM standards to determinate the density, and from TAPPI to the chemical analysis of wood. The wood was anatomically described and illustrated with photomicrographs. The woody tissue consist mainly of fibers (60 ± 3,4%) and rays (20 ± 2,3%), totaling approximately 80%. The remaining, in other words, 20% are divided into vessels (12 ± 4%) and axial parenchyma (8 ± 3%). The mean values, to the basic density (pb) and weighted density (ppond), were 0,539 and 0,555 g/cm³, respectively. The macromolecular constituents of heartwood and sapwood were determinate separately. The average content found for extractives (18,92; 6,32%); Klason lignin (17,58; 17,55%); holocellulose (63,45; 78,59%); alpha-cellulose ( 35,44; 44,38%); hemicelluloses (28,01; 34,21%) and ashes (1,08; 1,35%), to the heartwood and sapwood, respectively, totaling 102,42 ± 3,1%. The Tajuva s wood brings together the anatomical characteristics prevalent in Moraceae, framing the specie in their respective botanical family. It is considered an evolved specie anatomically. The density presents a decrease in the values in relation to the axial position of the plant. The heartwood is constituted of phenolic compounds and acids in a higher proportion relative to the sapwood, which presents higher starch contents. Studies about the natural durability and the wood quality are fundamental to indicate the best application of wood.
A eminência da construção da barragem Panambi, no município de Alecrim, Rio Grande do Sul, afetando o município de Porto Mauá, a qual alagará milhares de hectares de mata atlântica, habitat da Maclura tinctoria e, a grande exploração da espécie na região motivaram o início desse trabalho de pesquisa. Popularmente, a espécie é conhecida como Tajuva, apresenta porte arbóreo, e pertence à família botânica Moraceae, nativa do Rio Grande do Sul. É uma espécie semicaducifólia, com altura entre 10 a 30 metros e, com até 100 cm de diâmetro; fuste curto, com casca lisa, verde acinzentada com numerosas lenticelas amareladas, muitas vezes, com presença de espinhos ramificados. O estudo teve como objetivo a descrição anatômica, a caracterização química e a determinação das densidades básica e ponderada da madeira de Maclura tinctoria (L) D. Don ex Steud. As cinco árvores estudadas foram obtidas através de licenciamento ambiental, de acordo com a legislação vigente. Três amostras do lenho, retiradas do DAP foram utilizadas para a confecção de lâminas histológicas e para a quantificação das fibras. Para a determinação da densidade da madeira e para as análises químicas da madeira, foram retirados discos do tronco e divididos em cunhas. Foram utilizadas cunhas opostas retiradas de seis alturas pré-estabelecidas (base, DAP, 25, 50, 75 e 100% da altura comercial). Utilizou-se as normas da ASTM para determinação da densidade, e da TAPPI para as análises químicas da madeira. O lenho foi anatomicamente descrito e ilustrado com fotomicrografias. O tecido lenhoso é constituído principalmente por fibras (60 ± 3,4%) e raios (20 ± 2,3%), totalizando aproximadamente 80%. O restante, ou seja, 20 % estão divididos entre vasos (12 ± 4%) e parênquima axial (8 ± 3%). Os valores médios, para a densidade básica média (ρb) e ponderada (ρpond), foram de 0,539 e 0,555 g/cm³, respectivamente. Os constituintes macromoleculares da madeira de cerne e alburno foram determinados separadamente. Os teores médios encontrados para extrativos totais (18,92; 6,32%); lignina Klason (17,58; 17,55%); holocelulose (63,45; 78,59%); alfa celulose (35,44; 44,38%); hemiceluloses (28,01; 34,21%) e cinzas (1,08; 1,35%), para cerne e alburno, respectivamente, totalizando 102,42 ± 3,1%. O lenho da Tajuva reúne as características anatômicas predominantes em Moraceae, enquadrando a espécie em sua respectiva família botânica. É considerada uma espécie evoluída anatomicamente. A densidade apresenta decréscimo de valores em relação à posição axial da planta. O cerne é constituído por compostos fenólicos e ácidos em maior proporção em relação ao alburno, que apresenta maiores teores de amido. Estudos sobre a durabilidade natural e a qualidade da madeira são fundamentais para indicar a melhor aplicação da madeira.

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Wang, Dongmei, Dwight Bowman, Heidi Brown, Laura Harrington, Phillip Kaufman, Tanja McKay, Charles Nelson, Julia Sharp i Robert Lund. "Factors influencing U.S. canine heartworm (Dirofilaria immitis) prevalence". BioMed Central, 2014. http://hdl.handle.net/10150/610230.

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BACKGROUND:This paper examines the individual factors that influence prevalence rates of canine heartworm in the contiguous United States. A data set provided by the Companion Animal Parasite Council, which contains county-by-county results of over nine million heartworm tests conducted during 2011 and 2012, is analyzed for predictive structure. The goal is to identify the factors that are important in predicting high canine heartworm prevalence rates.METHODS:The factors considered in this study are those envisioned to impact whether a dog is likely to have heartworm. The factors include climate conditions (annual temperature, precipitation, and relative humidity), socio-economic conditions (population density, household income), local topography (surface water and forestation coverage, elevation), and vector presence (several mosquito species). A baseline heartworm prevalence map is constructed using estimated proportions of positive tests in each county of the United States. A smoothing algorithm is employed to remove localized small-scale variation and highlight large-scale structures of the prevalence rates. Logistic regression is used to identify significant factors for predicting heartworm prevalence.RESULTS:All of the examined factors have power in predicting heartworm prevalence, including median household income, annual temperature, county elevation, and presence of the mosquitoes Aedes trivittatus, Aedes sierrensis and Culex quinquefasciatus. Interactions among factors also exist.CONCLUSIONS:The factors identified are significant in predicting heartworm prevalence. The factor list is likely incomplete due to data deficiencies. For example, coyotes and feral dogs are known reservoirs of heartworm infection. Unfortunately, no complete data of their populations were available. The regression model considered is currently being explored to forecast future values of heartworm prevalence.

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Bate, Kathleen J. "Studies on the extraction, fractionation and degradation of ellagitannins from oak heartwoods". Thesis, Heriot-Watt University, 1995. http://hdl.handle.net/10399/653.

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Fenoff, Roy S. "A survey of Wyoming mosquitoes for vectors of dog heartworm". Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1317326331&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Litster, Annette Lorna. "The pathogenesis of the acute death syndrome in feline heartworm disease /". St. Lucia, Qld, 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17805.pdf.

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Brown, Heidi, Laura Harrington, Phillip Kaufman, Tanja McKay, Dwight Bowman, C. Nelson, Dongmei Wang i Robert Lund. "Key factors influencing canine heartworm, Dirofilaria immitis, in the United States". BioMed Central, 2012. http://hdl.handle.net/10150/610229.

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An examination of the Companion Animal Parasite Council's (CAPC) canine heartworm data to clarify the spatial prevalence of heartworm in the United States. Factors thought to influence the spatial risk of disease, as identified in a recent CAPC workshop, are discussed.

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Legoas, Roger Chambi. "Efeito do potássio e do sódio no crescimento e nas propriedades do lenho de árvores de Eucalyptus grandis sob duas condições de regime hídrico". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-08032016-134053/.

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No contexto das mudanças climáticas, a sobrevivência e a produtividade das plantações de eucaliptos poderão ser afetadas. Assim, são necessárias pesquisas em nutrição florestal, como a avaliação do K e do Na e sua interação com a disponibilidade hídrica com o crescimento e propriedades do lenho de eucaliptos. Em experimento instalado, em 20 de junho de 2010 de tipo \"Split-plot\", foram avaliadas as árvores de Eucalyptus grandis submetidas a dois regimes hídricos (100% e 63%) e três tipos de fertilização (K, Na e controle). O diâmetro do tronco (cada 15 dias, com dendrômetros) e a altura total (cada 6 meses) das árvores foram mensurados no período do 40º ao 61º mês. A umidade do solo foi analisada semanalmente e a precipitação e temperatura diariamente. Foram analisadas as propriedades do lenho de 48 árvores, no 47º mês, por amostragem destrutiva, avaliando-se a sua densidade aparente, densidade básica, estrutura anatômica e proporção cerne/alburno. Os resultados mostraram que a precipitação influenciou significativamente o crescimento das árvores, seguindo-se a temperatura mínima e a umidade do solo. O K e o Na mostraram interação com a precipitação, (i) no período seco, com a redução do incremento do tronco das árvores com o Na e a sua paralisação com o K, (ii) no período chuvoso, com o aumento do incremento em diâmetro e altura do tronco, em relação ao controle. O Na em relação ao K resultou em menor crescimento das árvores de eucalipto. Com a exclusão de 37% da chuva houve efeito negativo nas árvores com K; no tratamento controle e com aplicação de Na a exclusão não mostrou efeito significativo até o 58º mês. Em relação à (i) densidade do lenho das árvores- ocorreu a sua diminuição com K e Na (menor com Na), e incremento com a menor disponibilidade hídrica; K não diminuiu a densidade sob maior disponibilidade hídrica; (ii) anatomia do lenho- observaram-se vasos de maior diâmetro e menor frequência com K e Na (maior com K); as fibras apresentaram variação significativa com Na (com fibras mais longas e largas com menor espessura da parede); a menor disponibilidade hídrica resultante da exclusão de 37% da chuva não afetou aos vasos e fibras; (iii) relação cerne/alburno- o K e Na promoveram a formação de maior proporção de cerne em relação às árvores do tratamento controle, sem influência significativa da exclusão parcial de chuva. Relações entre anatomia e densidade do lenho mostraram que mudanças nas dimensões das fibras foram acompanhadas de mudanças na densidade do lenho; e maior taxa de crescimento nem sempre se relaciona com a diminuição da densidade do lenho. Os resultados indicaram que a perda de características desejáveis na densidade, fibras e proporção de alburno, com a adição de K ou Na (principalmente Na) na adubação básica, são altamente compensados pela maior produção de lenho, no entanto em regiões mais áridas e com maior risco de seca prolongada, potássio e sódio podem agravar o déficit hídrico.
In the context of climate change, survival and productivity of eucalyptus plantations may be affected. Thus, research is needed on nutrition and forest ecophysiology, such as the evaluation of K and Na and their interaction with water availability on the growth and wood properties of eucalyptus. In a split-plot type, experiment installed on June 20, 2010 we evaluated Eucalyptus grandis trees submitted to two water regimes (100% and 63%) and three fertilizer supplies (K, Na and control). The stem diameter was measured every 15 days with dendrometers and total height, every 6 months in the period from 40th to 61st month. Soil moisture was analyzed weekly and precipitation and temperature daily. The wood properties of 48 trees were analyzed after 47 months, by destructive sampling, evaluating their apparent density, specific gravity, anatomical structure and heartwood/sapwood proportion. The results showed that precipitation significantly influenced the growth of the trees, followed by the minimum temperature and soil moisture. K and Na showed interaction with precipitation, (i) in the dry season, by reducing the growth of the tree trunks with Na and its stoppage with K, (ii) during the rainy season, with increasing growth in diameter and height of the trunk, compared with the control. The Na, as compared to K, resulted in lower growth of the eucalyptus trees. With the artificial exclusion of 37% of throughfall there was a negative effect on the growth of trees fertilized with K; but in the control and Na treatment the rainfall exclusion showed no significant effect until 58º month. In relation to (i) density of the wood of trees, there was a decrease in K and Na (lower with Na), and an increase with lower water availability; although the K did not reduce the density under higher water availability; (ii) wood anatomy- larger vessels with lower frequency were formed with K and Na supply (with higher K); the fibers showed significant variations with Na (longer and wider fibers with smaller wall thickness); and the lower water availability from the of 37% rainfall exclusion did not affect vessels and fibers; (iii) Heartwood/sapwood ratio; K and Na promoted the formation of larger proportion of heartwood in relation to the trees from the control treatment, and there was no significant influence of the partial rainfall exclusion. Relationships between anatomy and wood density showed that changes in fiber dimensions were accompanied by changes in the wood density; and the higher growth rate is not always associated with decreased wood density. The results indicate that the loss of desirable characteristics in density, fiber and proportion of sapwood, with the addition of K or Na (mainly Na) in the basic fertilization are highly compensated by the increased wood production, though in more arid regions with increased risk of prolonged drought, potassium and sodium can aggravate water deficit.

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Grim, Devin Christine. "La Crosse virus and Dirofilaria immitis: Abundance of Potential Vectors in Southwestern Virginia and the Effects of Dual Infection on Aedes albopictus and Ochlerotatus triseriatus". Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/46195.

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Microfilarial enhancement of viral transmission is well documented, however only one previously studied model used components that occur together in nature and therefore has realistic implications. La Crosse (LAC) virus encephalitis is the most common mosquito-borne illness affecting children in the United States. LAC virus is prevalent in the Great Lake and Mid-Atlantic states and coincidently this area overlaps the region of highest infection for Dirofilaria immitis, the nematode that cause canine heartworm disease. Ae. albopictus and Oc. triseriatus are important vectors of La Crosse virus and among the numerous species able to transmit D. immitis. In this study, Aedes albopictus and Ochlerotatus triseriatus were infected with La Crosse virus and Dirofilaria immitis to determine the effects of dual infection on the dissemination and transmission of the virus. The effects of dual infection varied between the species tested. Ae. albopictus had significantly higher tolerance to D. immitis infection than Oc. triseriatus. Dissemination for dually infected Ae. albopictus were higher than the control group for all days tested, except one. Transmission rates for D. immitis infected Ae. albopictus were significantly higher than the control group on day 14 post infection. No microfilarial enhancement of viral dissemination or transmission was observed for Oc. triseriatus. The infection, dissemination, and tranmission rates were low for both species compared to rates of previous studies. Low rates could be a result of low susceptibility for the strains tested. In a second study, mosquitoes were collected from two counties in Southwestern Virginia to determine the abundance of potential La Crosse virus and D. immitis vector species. The abundance and distribution of mosquito species were examined in 2003 and 2004 using gravid traps. An unexpected finding was the significant increase in the abundance of Ochlerotatus japonicus. In 2003, collections were made over 192 trap nights from June to August yielding 5,879 mosquitoes of which only 24 were Oc. japonicus. In 2004, 12,151 mosquitoes were trapped from June to September over 160 trap nights. Oc. japonicus was the second most abundant mosquito species and the dominant Ochlerotatus species collected in gravid traps. Oc. japonicus was collected in low numbers in June, but the abundance increased significantly in July and remained consistent throughout the rest of the season. Of the other major mosquito species collected in this study, only Aedes albopictus exhibited a similar seasonal pattern as Oc. japonicus. Other biological similarities of Oc. japonicus and Ae. albopictus are discussed.
Master of Science in Life Sciences

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Sacks, Benjamin Nicholas. "The distribution and abundance of canine heartworm (Dirofilaria immitis) in California coyotes (Canis latrans) /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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Almeida, Carla de. "Prevalência de dirofilariose felina na região do Sado". Bachelor's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2010. http://hdl.handle.net/10400.5/2517.

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Dissertação de Mestrado Integrado em Medicina Veterinária
A Dirofilariose é uma doença parasitária transmitida por um vector e causada pelo nemátode da espécie Dirofilaria immitis. O cão é o hospedeiro definitivo do parasita, no entanto, tem sido relatado a ocorrência desta parasitose em outros animais, nomeadamente no gato doméstico. Apesar de se tratar de uma doença emergente, bem conhecida da população Médico- Veterinária e proprietários quando ocorre em cães, é frequentemente subdiagnosticada na população felina. Para tal contribui a limitação dos testes de diagnóstico existentes e o facto de a doença apresentar na espécie felina sinais clínicos inespecíficos, muitas vezes transitórios ou até mesmo verificar-se a ocorrência de morte do animal sem confirmação da infecção. Também é frequente os animais apresentarem-se amicrofilarémicos e as alterações laboratoriais e radiográficas serem transitórias ou mesmo ausentes. Estudos epidemiológicos já realizados noutros países confirmaram que em qualquer área onde existam cães infectados com o parasita, a doença pode ocorrer em gatos embora com uma menor taxa de incidência. No presente trabalho foi realizado um rastreio de dirofilariose felina numa zona endémica para a dirofilariose canina, nomeadamente na região do Sado. Este foi um estudo pioneiro em Portugal, tendo sido usado pela primeira vez o teste de detecção de antigénio D.immitis “SNAP® Feline Triple®”, que apresenta elevada sensibilidade e especificidade. A amostra foi constituída por 86 gatos com mais de 6 meses de idade. A prevalência de dirofilariose felina obtida neste estudo foi de 1,2% (1/86) e veio documentar pela primeira vez a existência da infecção felina na região do Sado. Este estudo enfatiza a necessidade de sensibilizar os colegas veterinários e proprietários para esta doença e sua prevenção.
ABSTRACT - PREVALENCE OF FELINE HEARTWORM IN THE SADO REGION - Heartworm is a parasitic disease transmitted by a vector and caused by a nematode of the Dirofilaria immitis species. The dog is the definitive host of the parasite, although it has been reported the occurancy of this parasitosis in other animals, namely the domestic cat. Although it’s an emerging disease, well known by the Veterinarian population and dog owners, it’s frequently under diagnosed in the feline population. The limitations of the existing diagnostic tests and the fact that this parasitic disease presents with unspecific signs in the feline specie, ranging from transient symptoms to sudden death, concur to the lack of knowledge about the feline infection. The amicrofilaremic state and the transient or absent laboratory and radiology changes are common. Epidemiological studies conducted in some countries have confirmed that in any area where dogs are infected with the parasite, the disease may occur in cats but in a smaller incidence rate. The present study performed a screening on the feline heartworm in an endemic area of canine heartworm, the Sado region. This was a pioneer study in Portugal because it used the high sensitivity and specificity “SNAP® Feline Triple®” D. immitis screening test, having as a sample population 86 cats over 6 months of age. The prevalence of feline heartworm obtained in this study was 1,2% (1/86) documenting for the first time the existence of feline infection in the Sado region. This study raises the need for awareness among fellow veterinarians and owners towards this disease and its prevention.

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Dian, Rebekah Lynn. "Vector Competence of Northern California Mosquitoes for Dirofilaria immitis (Spirurida: Onchocercidae)". Scholarly Commons, 2018. https://scholarlycommons.pacific.edu/uop_etds/3543.

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Dirofilaria immitis, commonly known as dog heartworm, is a dangerous filarial nematode that is transmitted by a mosquito vector. Although this parasite is historically localized to regions closer to the equator, the last few decades have experienced an increase in the amount of dog heartworm cases in Northern California, most notably in Lake and San Joaquin Counties. The primary vector of D. immitis in Northern California is Aedes sierrensis, but it is not prevalent enough in some counties to explain the increase in infections. Because of this, more prevalent and abundant species should be assessed for their ability to transmit heartworm. Culex pipiens complex (wild) and Culiseta incidens (laboratory-raised colonies) were chosen as potential vectors during this study due to their ability to meet several key vector criteria, their relative abundance in the areas of interest, and the fact that they habitually take bloodmeals from domestic dogs. Additionally, Ae. sierrensis colonies were used in this study, based on previous knowledge that they are highly competent vectors. Female mosquitoes were infected with 2.5, 5, or 10 mff/ul of D. immitis-infected blood, and decapitated at 15, 18, and 21 days post-infection. Mosquitoes were subsequently tested via qPCR for the presence and relative quantification of D. immitis DNA. We found that Ae. sierrensis and Cx. pipiens complex were both able to support the development of D. immitis to its infective stage, while Cs. incidens was not a competent vector. We also concluded that including a standard curve of known amounts of D. immitis larvae makes it possible to approximate the intensity of the infection in the mosquito. The identification of these important vectors, and the ability to assess infection intensity, may be helpful in the continued vector control efforts in Northern California and beyond.

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BARBOSA, Marco Antônio Granja. "Avaliação clínica, hematológica e bioquímica sérica de cães inoculados experimentalmente, por via intravenosa com extrato bruto de Dirofilaria immitis (Leidy, 1856)". Universidade Federal Rural de Pernambuco, 2004. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5777.

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Studies were performed in two groups of mixed-breed male dogs containing six (Experimental Group) and two (Control Group) animals which were administered IV a crude, whole-body extract of female heartworms or saline solution respectively. The frequency of clinical signs and shock-like reaction as well as changes in clinical parameters such as electrocardiographic record, RBC and WBC counts, serum alanine amino transferase, aspartate amino transferase, creatine phosphokinase and also urea were monitored. The results had been analyzed by the test of Wilcoxon e Mann-Whitney for Clinical hematological, clinical chemistry and by the test of Fischer to electrocardiographic values respectively. Shock with clinical signs such as the pale color of the visible mucous membranes, respiratory disorders, developed in all crude, whole-body extract inoculated dogs. It was observed a significative difference not only between the lynfocytes count and CPK values but also with RBC and eosinophil count absolute. These results indicated that some products present on whole-body extract of female heartworms might be responsible for the onset of shock in dogs.
Foram realizados estudos em dois grupos de caninos,machos, sem raça definida, sendo um grupo experimental composto de seis animais e dois animais no grupo controle, os quais foram inoculados com extrato bruto de fêmeas de Dirofilaria immitis e solução salina respectivamente, com objetivo de avaliar as alterações clínicas, hematológicas e bioquímico séricas. A freqüência dos sinais clínicos apresentados durante o choque foram monitoradas, assim como as modificações nos parâmetros eletrocardiográficos, hematológicos, bioquímico séricos no período compreendido entre cinco minutos a 24 horas após o inicio do experimento. Os resultados foram analisados através dos testes de Wilcoxon e Mann-Witney para as alterações clínicas, hematológicas e bioquímicas, e o teste de Fischer para os valores do eletrocardiograma. Sinais clínicos compatíveis com choque como palidez das membranas mucosas visíveis e distúrbios respiratórios, foram observados em todos os animais inoculados com extrato bruto de Dirofilaria immitis. Diferença significativa foi observada não apenas entre a contagem de linfócitos e os valores de CK, mas também na contagem total de hemácias e na contagem absoluta de eosinófilos.Os resultados indicam que substâncias presentes nos nematóides fêmeas foram responsáveis pelo aparecimento de choque.

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Cohen, Sharon. "Sarconema eurycerca (Wehr) : the heartworm of swans and the role of Trinoton anserinum (F) as an intermediate host". Thesis, Loughborough University, 1988. https://dspace.lboro.ac.uk/2134/6728.

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All filarial nematodes of the family Onchocercidae are parasites of vertebrates and require intermediate insect hosts for completion of their life-cycles. Eighteen genera within this family are known to infect birds but very few of the associated intermediate hosts have been elucidated. Sarconema eurycerca (Wehr) is a filarial nematode of swans and geese. A recent study of S. eurycerca in American Whistling Swans (Cygnus c. columbianus ) has demonstrated that the intermediate insect host is a feather louse, Trinoton anserinum (Fabricius) (Seegar, 1977). The main aim of the present study was to investigate the relationship between S. eurycerca and British swans and to determine whether T. anserinum is the intermediate host of the parasite in this country. A total of 1128 swans (of all species) were examined from sites in Britain, Denmark and Iceland. Infected swans were detected by examining blood samples for larval stages of S. eurycerca (microfilariae) using a new sedimentation technique developed in the study. An overall incidence of 15.0% was recorded with a significantly higher proportion of juvenile swans being infected. The microfilariae of S. eurycerca exhibited a diurnal sub-periodic rhythm within the host, with maximum counts occurring between 11.00 and 19.00 hours in the peripheral blood supply. T. anserinum was found to satisfy all the attributes required of an intermediate insect host. As an obligate ectoparasite, T. anserinum has a close spatial and temporal relationship with the swan. T. anserinum appears to be capable of ingesting microfilarie of S. eurycerca whilst feeding on blood. All developing larval stages of S. eurycerca were found in T. anserinum and the louse was very mobile and capable of transmitting the nematode from one swan to another. Examinations were made of the nematode, its morphology and pathological effects on both heart tissue and blood components of the swan. Significantly higher lymphocyte percentages and lower eosinophil percentages, haematocrit and red blood corpuscle counts were recorded in swans infected with S. eurycerca.

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Freitas, Sónia Melissa Fernandes de. "Abordagem à dirofilariose cardiopulmonar canina na região da Madeira". Bachelor's thesis, Escola Superior Agrária de Elvas, 2020. http://hdl.handle.net/10400.26/36570.

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Este relatório refere-se ao estágio final do curso de enfermagem veterinária, realizado no Hospital Veterinário da Madeira, com duração total de 7 semanas devido às contingências provocadas pelo Coronavirus Disease 2019 (Covid-19). O objetivo foi consolidar os conhecimentos adquiridos nos 3 anos do curso e pô-los em prática, em especial na área de parasitologia onde se insere a dirofilariose, doença endémica na região. Durante o tempo de estágio, a aluna teve a oportunidade de trabalhar em várias áreas, destacando o internamento, onde passou a maior parte do tempo, assim como o laboratório onde foram realizadas as técnicas de diagnóstico. Para um possível diagnóstico da presença de Dirofilariose Cardiopulmonar Canina (DCC), a aluna recolheu amostras de sangue a 27 cães de forma aleatória e avaliou pelo método de gota fresca e esfregaço sanguíneo, obtendo 8 resultados positivos. Desses 8 animais, 7 nunca tinham ido a uma consulta médico-veterinária, todos viviam em ambientes externos ou mistos, sem qualquer tipo de protocolo preventivo para DCC e não estavam desparasitados nem vacinados. Com o objetivo de avaliar o conhecimento dos tutores em relação à doença, identificar o concelho onde se insere o maior número de casos positivos, quantos fazem tratamento nos animais positivos e se esses que tiveram animais positivos começarama fazer prevenção nos seus novos animais, a aluna criou questionários para a população da Região Autónoma da Madeira. Esteve disponível online durante 2 meses, nas plataformas sociais da aluna e conseguiu uma amostra total de 319 respostas, com maior foco na cidade do Funchal. Paralelamente foi enviado por email para as clínicas/hospital da região um questionário com o objetivo de estimar o número de casos anuais positivos, tipo de técnica usada no despiste e em que altura do ano há maior número de casos, obtendo uma amostra de 3 num total de 21
This report refers to the final internship of the veterinary nurse course, which took place at the Veterinary Hospital, Hospital Veterinário da Madeira, with a full duration of 7 weeks due to the contingencies caused by the Coronavirus Disease 2019 (Covid-19). The goal was to consolidate the knowledge acquired in the 3 years of the course and put it into practice, especially in the area of parasitology where heartworm is insered, which is an endemic disease in the region. During the internship period, the student had the opportunity to work in several areas, highlighting the hospital ward, where she spent most of the time, as well as the laboratory where the diagnostic techniques were performed. For a possible diagnosis of the presence Canine Cardiopulmonary Heartworm Disease (CHD), the student collected blood samples from 27 dogs at random and analyzed them using the fresh drop and blood smear method, obtaining 8 positive results. Of these 8 animals, 7 had never been to a veterinary consultation, all lived outside or in mixed environments, without any tyoe of preventive protocol for CHD and were not dewormed or vaccinated. In order to assess the knowledge of tutors in relation to the disease, to identify the county where the greatest number of positive cases are found, how many treat positive animals and if those who had positive animals started to do prevention in their new animals, the studente created questionnaires for the population of the Autonomous Region of Madeira. It was available online for 2 months, on the student’s social platforms and obtained a total sample of 319 responses, with greater focus on the city of Funchal. In parallel, a questionnaire was sent by email to clinics/hospitals in the region in order to estimate the number of positive annual cases, the type of technique used in screening and what time of year there are more cases, obtaining a total sample of 3 out of a total of 21.
info:eu-repo/semantics/publishedVersion

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COSTA, Lorena Adão Vescovi Séllos. "Avaliação e caracterização das alterações do trato respiratório caudal de cães com infecção natural por Dirofilaria immitis (Leidy, 1856) por meio de tomografia computadorizada". Universidade Federal Rural de Pernambuco, 2016. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/4737.

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The main clinical signs of heartworm disease in dogs are characterized by respiratory manifestations which are associated to signs such as dry cough, exercise intolerance, tachypnea, hemoptysis and dyspnea. Although, the radiographic examination of thorax has been used to identify changes in the pulmonary patterns, the Computed Tomography (CT) has been currently considered the method of choice for evaluation of pulmonary parenchyma and lower airways. Therefore, the aim of this study was to assess pulmonary changes in dogs naturally infected by Dirofilaria immitis by using CT. Domiciled dogs (n = 12) living in the Metropolitan Region of Recife were used in this study. All animals positive for D. immitis were physically examined, and analyzed through the microscopic examination of blood samples, serological analysis (D. immitis and Leishmania infantum), electrocardiography and CT. The quantitative assessment of pulmonary radiodensity presented mean value of -628.58 ± 56.60 HU, which was significantly higher than the normal parameter of lung parenchyma of dogs. Moreover, the results revealed the presence of interstitial infiltrate, increase of tortuosity of caudal arteries, increase of bronchial arteries and gap filling of pulmonary artery were present in different degrees, including in the animals that present occult heartworm. Afterwards, a female Dachshund with eight-year-old was treated with Ivermectin and Doxycycline, being monitored twice by CT. The CT examination performed before the treatment showed the presence of D. immitis adults in the pulmonary artery, vascular tortuosity and parenchymal inflammation. After therapy, it was observed an improvement in the clinical status of the animal, which scored negative at serological examination. In addition, it was observed the remission of pulmonary changes and absence of D. immitis adults in blood vessels and heart chambers. In conclusion, the CT may be considered an important tool to detect changes in pulmonary parenchyma of dogs naturally infected by D. immitis, in addition, it allows the diagnosis of occult heartworm.
As principais manifestações clínicas da dirofilariose em cães são respiratórias e causam prejuízo à função pulmonar, que se encontra associada a sinais clínicos de tosse seca, intolerância ao exercício, taquipneia, hemoptise e dispneia. Apesar do estudo radiográfico de tórax permitir a identificação da alteração de padrões pulmonares da doença, a tomografia computadorizada (TC) tem sido considerada o exame de eleição para avaliação do parênquima pulmonar e vias aéreas inferiores. Sendo assim, o objetivo deste trabalho foi avaliar por meio da TC as alterações pulmonares de cães infectados naturalmente por Dirofilaria immitis. Para tanto, inicialmente foram selecionados 12 cães com diagnósticos positivos para dirofilariose, domiciliados na região metropolitana do Recife, Pernambuco, Brasil, os quais foram submetidos ao exame clínico, pesquisa de microfilaria circulante, exame sorológico, pesquisa de anticorpos IgG anti- Leishmania infantum, eletrocardiográfico e TC pulmonar apresentou valores médios de -628,58 ± 56,60 HU, apresentando-se significativamente maior quando comparado com os valores do parênquima pulmonar para cães hígidos. Os resultados revelaram que a presença de infiltrado intersticial periarterial, aumento e tortuosidade das artérias pulmonares caudais, aumento da relação arteriobronquial e falhas de contraste iodado nas artérias pulmonares foram presentes em graus variáveis, inclusive nos cães com dirofilariose oculta. Posteriormente, um desses animais, uma cadela de oito anos de idade, da raça Dachshund foi submetida ao tratamento com ivermectina e doxiciclina, sendo monitorada em dois momentos pela TC. Dentre os achados no exame tomográfico pré-tratamento, destacam-se sinais tromboembolismo vascular sugerindo a presença de D. immitis em artéria pulmonar, tortuosidade vascular e processo inflamatório parenquimatoso. Após a terapia estabelecida o animal apresentou pesquisa de antígeno circulante negativa, além da remissão dos achados pulmonares, ausência de imagens sugestivas de D. immitis em vasos e câmaras cardíacas, e melhora clínica significativa. Conclui-se que a TC pode ser utilizada como ferramenta no estadiamento das alterações causadas pela infecção por D. immitis em cães, monitorar a terapia, além de permitir o diagnóstico da dirofilariose oculta.

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Ferreira, João Pedro Cordas. "Doseamento do d-dímero como método de diagnóstico de tromboembolismo pulmonar em cães com dirofilariose cardíaca em Portugal". Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2015. http://hdl.handle.net/10400.5/10566.

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Dissertação de Mestrado Integrado em Medicina Veterinária
O d-dímero é um produto que resulta da degradação de um coágulo de fibrina estabilizado. O aumento da sua concentração plasmática reflete um aumento no processo de fibrinólise e indiretamente na formação de coágulos. O presente estudo tem como objetivo analisar a utilidade do doseamento da concentração plasmática do d-dímero como método de avaliar a ocorrência de tromboembolismos em cães com dirofilariose, por Dirofilaria immitis, em diferentes estádios da doença. Este estudo incidiu numa amostra de 19 animais, diagnosticados com dirofilariose cardiopulmonar, provenientes da área de Setúbal, divididos em quatro grupos: 1 (n=3), 2 (n=5), 3 (n=6) e 4 (n=5) por ordem crescente de estadiamento. Foi comparado o valor das concentrações plasmáticas de d-dímero entre os variados grupos. Adicionalmente foi também analisada uma possível associação entre determinados sinais clínicos, ocorrência de complicações durante o tratamento da doença e os animais com valores elevados do d-dímero. Em relação ao doseamento do d-dímero entre os variados grupos, todos os grupos revelaram valores de média de d-dímero superiores ao valor de referência estipulado (<0,40 mg/dl). As médias foram de: 1,7633 mg/dl; 0,6140 mg/dl; 1,1450 mg/dl e 1,0740 mg/dl, por ordem crescente de estadiamento. Igualmente para esta ordem de estadiamento, a percentagem de animais com o valor aumentado de d-dímero foi de 100% (3/3), 60% (3/5), 66% (4/6) e 80% (4/5). Não foi encontrada nenhuma associação entre o valor da concentração de d-dímero obtido e os variados grupos (p=0,340). Também não foi encontrada relação entre um valor de d-dímero acima do normal e os variados sinais clínicos com interesse para a doença: presença de microfilarémia (p=0,338), presença de sinais cardíacos (p=0,120) como sopro cardíaco (p=0,363) ou cardiomegália (p=0,406), presença de sinais respiratórios (p=0,047) ou mesmo entre a combinação dos dois, animais com sinais respiratórios e também cardíacos (p=0,026). Da mesma forma, não foi encontrada associação entre um doseamento de d-dímero acima do normal e a presença de anemia (p=0,143), de trombocitopenia (p=0,699) ou de ambos os parâmetros em simultâneo (p=0,171). Também não ficou demonstrada a associação entre os valores elevados de d-dímeros iniciais e a ocorrência de complicações clínicas durante o tratamento (p=0,733). A utilização do doseamento do d-dímero apresenta neste estudo um resultado desfavorável, não tendo sido capaz de demonstrar a correlação entre os valores de d-dímero aumentados e a ocorrência de tromboembolismos nos vários estádios da doença.
ABSTRACT - The d-dimer is a product that results from the degradation of a stabilized fibrin clot. The increase of its plasma concentration reflects an increase in fibrinolysis process and indirectly in the formation of clots. This study aims to analyze the usefulness of the measurement of plasma concentration of d-dimer as a method to evaluate the occurrence of thromboembolism in dogs with heartworm disease in different stages of the disease. This study focused on a sample of 19 animals from the area of Setúbal, Portugal, divided into four groups: 1 (n = 3), 2 (n = 5), 3 (n = 6) and 4 (n = 5) based on the classification of the severity of the disease. It compared the value of the plasma concentrations of d-dimer among the various groups. Additionally it was also analyzed a possible association between some clinical signs, the presence of medical complications during the treatment of the disease and the number of animals that had concentrations of d-dimers above the normal limit. Regarding the determination of d-dimer, all groups showed average above the prescribed reference value (<0.40 mg / dl). The averages were: 1.7633 mg / dl; 0.6140 mg / dL; 1.1450 mg / dl and 1.0740 mg / dl, in ascending order of disease staging. Also for this staging order, the percentage of animals with an increased amount of d-dimer were 100% (3/3), 60% (3/5), 66% (4/6) and 80% (4/5), no significant association between the value of d-dimer concentration obtained and the various groups was found (p = 0.340). There was also no association between a d-dimer value above normal and the varied clinical signs relevant to the disease: presence of microfilaremia (p = 0.338), presence of cardiac signals (p = 0.120) such as heart murmur (p = 0.363) or cardiomegaly (p = 0.406), presence of respiratory signs (p = 0.047) or even in combination of respiratory and cardiac signs (p = 0.026). Likewise, we found no association between a d-dimer assay above normal and the presence of anemia (p = 0.143), thrombocytopenia (p = 0.699) or both parameters simultaneously (p = 0.171). Also, the present study did not find any association between a d-dimer assay above normal and the appearance of clinical complications during the treatment of the disease (p=0,733). The use of the d-dimer assay in this study presents an unfavorable outcome and has not been able to demonstrate the association between the increased d-dimer values and the occurrence of thromboembolism in the various stages of the disease.

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38

Bróis, Paulo Jorge Marques. "Relatório de estágio em clínica e cirurgia de animais de companhia". Master's thesis, Universidade de Évora, 2006. http://hdl.handle.net/10174/19586.

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O estágio curricular a que se refere o presente relatório foi realizado no Hospital Veterinário do Baixo Alentejo, em Beja, entre 15/09/2014 e 15/03/2015, sob orientação do Dr. André Cláudio. Na primeira parte é apresentada a casuística acompanhada durante o estágio e a segunda parte consiste numa monografia referente ao tema “Dirofilariose canina”, onde é apresentada uma revisão bibliográfica seguida de um caso clínico. A dirofilariose canina é uma doença endémica em Portugal causada por nemátodes do género Dirofilaria, que têm como hospedeiros definitivos preferenciais os canídeos domésticos. A prevalência desta doença tem vindo a aumentar, contudo, é pouco conhecida pela população em geral. Devido à sua morbilidade e caráter zoonótico tem grande importância Médico- Veterinária e para os proprietários de cães;Abstract: Traineeship report in clinic and surgery of companion animals. The traineeship referred to in this report was carried out at the Veterinary Hospital of the Lower Alentejo, in Beja, between 15/09/2014 and 15/03/2015, under the guidance of Dr. André Cláudio. The first part presents the casuistry observed during this traineeship and the second part consists of a monograph regarding the topic "Canine heartworm disease" where a literature review followed by a case is presented. The canine heartworm disease is an endemic disease in Portugal caused by nematodes of the genus Dirofilaria, whose preferred definitive hosts are domestic canids. The prevalence of this disease has increased, however, is little known by the general population. Due to its morbidity and zoonotic characteristics, has great importance in the Medical Veterinary field and for the dog owners.

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Olsen-Mikitowiez, Victoria Michaelina. "Prevalence of Dirofilaria Immitis, The Causitive Agent in Canine Heartworm Disease, in Arizona from 2008 to 2011 Using Feral Canines as a Sentinel Species". Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/144918.

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Silva, Juliana de Sousa Moreira da. "Caracterização clínica e epidemiológica da dirofilariose cardiopulmonar canina no concelho de Benavente, Portugal". Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/16472.

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Dissertação de Mestrado Integrado em Medicina Veterinária
O concelho de Benavente localiza-se numa zona hiperendémica de dirofilariose cardiopulmonar canina. O presente estudo teve como principal objectivo a identificação das alterações clínicas mais significativas nos cães infectados e verificar se variáveis como a idade avançada, apresentação de microfilarémia, valores de d-dímero elevados ou animais em estádios avançados de doença constituíam factores de mau prognóstico para a população avaliada. Foram analisadas as fichas clínicas de 43 cães diagnosticados com dirofilariose cardiopulmonar que realizaram um ou mais dos seguintes exames complementares: radiografia torácica, hemograma, análises bioquímicas e doseamento do d-dímero. Realizou-se ainda o estadiamento dos indivíduos em classes de 1 a 4 recorrendo à combinação de todos os achados clínicos. Registou-se uma prevalência de dirofilariose cardiopulmonar canina de 60% no concelho de Benavente. Dos 43 cães diagnosticados, 44% encontravam-se assintomáticos. Ao exame físico, o achado mais comum foi a existência de um sopro cardíaco, seguido de letargia, dispneia e palidez das mucosas. Os sintomas mais frequentemente exibidos foram a tosse, registada em 30,2% dos animais e intolerância ao exercício, verificada em 20,9% dos indivíduos. Os achados clínicos mais relevantes foram a cardiomegália, o aumento das enzimas hepáticas ALT e AST, leucocitose, neutrofilia, eosinofilia e trombocitopénia no hemograma. Dos animais que efectuaram o doseamento do d-dímero, 45% apresentaram valores acima do valor de referência estipulado (> 0,4 mg/L). Para a pesquisa de factores de mau prognóstico na população em estudo, apenas foi encontrada uma associação estatisticamente significativa entre um estádio ≥ 3 e a morte (p=0,016). Globalmente os achados clínicos foram ao encontro do que está descrito na literatura. Neste estudo, verificou-se uma expressão superior de padrões pulmonares mistos e do aumento das enzimas hepáticas e uma menor frequência de eosinofilia e basofilia.
ABSTRACT - Clinical and epidemiologic characterization of canine cardiopulmonary dirofilariasis in the county of Benavente, Portugal - The county of Benavente is located in a hyperendemic area of canine heartworm disease. The present study aimed at the registration of the most significant clinical features in infected dogs and the identification of variables such as ageing, microfilaremia, high d-dimer values or advanced clinical stages of disease as poor prognosis factors for the evaluated population. The clinical files of 43 dogs diagnosed with heartworm disease were analyzed and the individuals were scanned with one or more of the following exams: thoracic radiography, serum biochemical profile, hemogram and measurement of plasma d-dimer levels. The combined clinicopathological findings were used to categorize the individuals in classes from grade 1 to 4. It was found a prevalence of 60% of canine heartworm disease in Benavente’s county. From the total 43 diagnosed dogs, 44% were assymptomatic. During the physical examination, the most frequent findings were the presence of a heart murmur, followed by lethargy, dyspnea and pallor. The most common symptoms were cough registered in 30.2% of the animals and exercise intolerance shown by 20.9% of the individuals. The most relevant clinical findings were cardiomegaly, elevation of ALT and AST hepatic enzymes, leucocytosis, neutrophilia, eosinophilia and thrombocytopenia. From those which performed the measurement of plasma d-dimer levels, 45% showed values above the stated reference value (> 0,4 mg/L). For the search of poor prognosis factors in the studied population it was found a single association between a class ≥ 3 and the animal death (p=0,016). The clinical findings were mainly concordant with the literature. In this study, there was a higher expression of mixed pulmonar patterns and elevated hepatic enzymes and a decreased frequency of eosinophilia and basophilia.
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41

Gouveia, Marta Isabel Marreiros Santa Ana Viegas. "Susceptibility of mosquito vectors to Dirofilaria immitis on Madeira Island, Portugal". Doctoral thesis, Universidade da Madeira, 2007. http://hdl.handle.net/10400.13/27.

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Dirofilaria immitis (Leidy, 1856), an agent of heartworm disease, is an important parasite from both the veterinary standpoint and as a model to study human filariasis. It is a mosquito-borne filarial nematode which inhabits the right ventricle and pulmonary arteries of dogs. D. immitis is an important disease agent on Madeira Island with about 30% of dogs testing positive for this worm. Nevertheless, the vectors of this parasite in Madeira have never been studied, nor has the interaction between pathogen and vector, or the environmental variables that might influence heartworm transmission. Innate susceptibility to infection is only one component of vector competence, and field isolation of naturally infected mosquitoes has shown the capability of D. immitis to exploit a great diversity of vector species under natural conditions. The purpose of this work was to determine which mosquitoes are vectors of heartworm disease, the relation between population density and environment, and the association between immune response of the vector to the filarial parasite. Seasonal abundance of Culex theileri and Culex pipiens molestus was studied. Correlation and canonical correspondence analysis were performed using abundance data of these two species with selected weather variables, including mean temperature, relative humidity and accumulated precipitation. The most important factor determining Cx. theileri abundance was accumulated precipitation, while Cx. pipiens molestus abundance did not have any relationship with weather variables. Field studies were performed to verify whether Cx. theileri Theobald functions as a natural vector of D. immitis on Madeira Island, Portugal. Cx. theileri tested positive for D. immitis for the first time. The same study was made regarding Cx. p. molestus. Two abnormal L2 stage filarial worms were found in Malpighian tubules in field caught Cx. p. molestus. In the laboratory, two strains of Cx. p. molestus were studied for their susceptibility to D. immitis. None presented infective-stage larvae. Finally, because Cx. p. molestus is an autogenous mosquito, we evaluated the reproductive costs when this mosquito mounts an immune response against D. immitis in the absence of a blood meal. This mosquito showed an active immune response when inoculated intrathoracically with microfilariae (mf) of the heartworm. The ovaries from mosquitoes undergoing melanotic encapsulation developed more eggs than those which could not melanize the mf. This fact is contradictory with some previous studies of reproductive costs in Armigeres subalbatus and Ochlerotatus trivittatus, and it was the first time that an autogenous mosquito was used to study this subject.

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42

Kurosaka, Jeffrey Allan. "Vector Competence of Aedes sierrensis and Culex pipiens complex (Diptera: Culicidae) for Dirofilaria immitis (Spirurida: Onchocercidae) in Northern California". Scholarly Commons, 2017. https://scholarlycommons.pacific.edu/uop_etds/2979.

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Dirofilaria immitis Leidy (dog heartworm) is a life-threatening parasite transmitted by mosquitoes to domestic dogs. Endemic in the eastern United States, cases have become more prevalent over the last few decades. While prevalence in California is generally low, Lake and San Joaquin Counties have reported rates comparable to the East Coast at 3.73% and 0.71%(CAPC 2017), respectively. Aedes sierrensis is thought to be responsible for transmission in California, but in some cases, it exists in inadequate quantities and temporal ranges to explain parasite activity. Based on Huang et al. (2013) and Tran (2016), bloodfeeding patterns, and other vector criteria, Culex pipiens complex and Culiseta incidens were chosen to evaluate for vector competence. Female field-caught mosquitoes were reared, infected (2.5-5 mff/μl), and decapitated at 15, 18, or 21 days post infection (dpi). Cs. incidens was reluctant to feed using an artificial feeding system and will require additional trials. On the contrary, trials on Ae. sierrensis and Cx. pipiens complex were both completed successfully. Both species were determined to be competent vectors of D. immitis. Based on our findings, more than half of Ae. sierrensis females produced emerging L3s by 21 dpi, while Cx. pipiens complex never produced L3s in more than 5% of females. In conjunction with other factors such as the detection of D. immitis in wild mosquitoes, host-seeking preferences for domestic dogs, and appropriate temporal overlap, this suggests that both Ae. sierrensis and Cx. pipiens complex may play central roles in Lake or San Joaquin Counties, CA when abundant. Targeted control efforts are necessary to reduce the incidence of canine heartworm in these areas. While Lake and San Joaquin Counties, CA were the focus of this study, our results may be applicable to the western United States when these species are relevant.

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43

Ogawa, Guilherme Maerschner. "Prevalência de Dirofilaria immitis (Leyd, 1856) em cães e sua ocorrência em mosquitos (Diptera, Culicidae) na cidade de Porto Velho, Rondônia, Brasil". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/42/42135/tde-20032014-150702/.

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A dirofilariose canina é uma parasitose de distribuição mundial cujo agente etiológico é um verme nemátoda filarióide. Em sua fase adulta, os vermes produzem microfilárias por meio de reprodução sexuada. Sua transmissão ocorre por meio de mosquitos que atuam como hospedeiros intermediários. No Brasil, até o momento, a dirofilariose canina foi encontrada em 15 estados de todas as regiões. A maioria dos estudos está concentrada nas regiões sudeste e sul. A prevalência nacional é de 2%, embora alguns trabalhos tenham encontrado prevalências locais mais elevadas. Neste trabalho apresentamos o primeiro registro de dirofilariose canina para o estado de Rondônia com mapas de distribuição dos cães positivos e análise de mosquitos. Amostras de sangue de 727 cães foram coletadas aleatoriamente na cidade de Porto Velho. As amostras forma analisadas em busca de microfilárias e antígenos circulantes usando duas técnicas: microscopia ótica de gota espessa corada com Giemsa e imunocromatografia de fluxo lateral (ICT). As amostras positivas foram também testadas por PCR, as negativas forma testadas na mesma técnica em pools. Mosquitos foram coletados no domicilio e peridomicílio de todos os casos de cães positivos, estes mosquitos foram testado por PCR em busca de DNA de Dirofilaria immitis. Um mapa de distribuição dos casos de cães positivos foi elaborado. Noventa e três amostras de sangue foram positivas no ICT, representando 12,8% da amostra total, nenhuma amostra foi positiva na gota espessa. O PCR das amostras de sangue resultou em 10% para as positivas no ICT e 0% nas negativas no mesmo teste. Entre os 93 cães positivos, 89 (95,7%) nasceram em Porto Velho. Nenhuma diferença estatística foi observada entre cães que moram em quintais ou intradomicílio. O mapa de distribuição indica um hotspot na região norte da cidade. O PCR dos mosquitos resultou em apenas um pool positivo. A transmissão de dirofilariose canina ocorre na cidade de Porto velho e a frequência que ocorre nos cães é considerada moderada. A técnica de imunocromatografia e PCR são mais eficazes na detecção de dirofilariose comparadas a gota espessa. A confirmação de transmissão de dirofilariose canina em Porto Velho, coloca esta doença no ranking de diagnóstico diferencial de nódulos pulmonares em Porto Velho.
Heartworm is an infectious disease with worldwide distribution. Mosquitoes acts as intermediary host and vectors. In Brazil, until now, heatworm was found in 15 states with an national average of 2%. This present work aims to report for the first time canine heartworm in the state of Rondônia and confirms the transmission of the disease in the state. Blood samples were randomly collected from 727 dogs in the municipality of Porto Velho. The samples were analyzed for the presence of microfilariae and circulating antigens using two different techniques: thick blood microscopy stained with Giemsa and immunochormatography for the detection of filarial antigens. Aiming to test the efficacy of the immunoassay test, all the positive cases were examined by PCR and pools of negative samples were also examined. Mosquitoes were collected at the domiciles presenting positive cases and analyzed by PCR. A distribution map was made with positive cases. Ninety three blood samples out of 727 (12.8%) were positive by the immunoassay technique and none by the thick smear method. All the positive cases by the immunoassay technique were examined by PCR and pools of all negatives samples were also examined resulting in 10% and 0% positivity frequency, respectively. Among the 93 positive dogs, 89 (95.7%) were born in Porto Velho. No differences in the frequency of infection were observed between dogs raised indoor or in the yards. The distribution map indicates a hotspot in the north area of the city. Mosquitoes were analyzed by PCR, resulting in only one positive pool. This result shows that the transmission of canine heartworm is occurring in the municipality of Porto Velho and has moderate prevalence among dogs. The immunoassay technique and the PCR method are more efficient in detecting D. immitis infections in dogs when compared to the blood smear technique. The confirmation of heartworm transmission in Porto Velho also includes this disease among the ranks of differential diagnosis of pulmonary nodules in humans in Rondônia.

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44

Chen, Terry, i 陳泰瑞. "Studies on Constituents of Heartwood of Erythrina arborescens". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/45350237504689580965.

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碩士
靜宜大學
應用化學系
88
Abstract Erythrina arborescens Roxb.(Leguminosae) is a large deciduous tree widely distributed in the subtropical regions. It is also often planted garden and roadside. From the methanolic extracts of the heartwood of Erythrina arborescens Roxb. fifteen compounds were found. These components are including long chain ester of frulic acids(A)、phytosterols(B)、phytosterol-glucoside(C)、β-sitosterol(D)、β-sitosterol-3-β-O-d-glucoside(E)、β-amyrin(F) 、lup-20(29)-ene-3-one(G)、oleanolic acid(H)、olean-12-ene-3β,28-diol(I)、ursolic acid(J)、olean-12-ene-3β,22β-diol(K)、3'',4''-methylenedioxy-(2'',3''：7,8)furanoflavone(L)、3'',4''-methylenedioxy-(2'',3''：7,8)furanoisoflavone(M)、lanceolatin B(N)、dihydroalpinumisoflavone(O). All of these were identified by spectroscopic and chemical methods. Among the above components, compound K、compound L、compound M、compound N、compound O were first isolated from this plant.

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45

Chen, Tai-Hung, i 陳泰宏. "Lignanoids and bioactivity study of Chamaecyparis formosensis heartwood". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/92180885095209536148.

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碩士
國立中興大學
化學系所
94
Taiwan red cypress（Chamaecyparis formosensis Matsum.）is an endemic precious tree specie grown in Taiwan. In this study the heartwood chips were extracted with methanol and carried on the cytotoxicity assay. The result of brine shrimp lethality test（BST）indicated the extractives of EtOAc soluble part from C. formosensi extracts had the potential（IC50＝15.36 ug/mL）to further study on their antitumor activity. In the isolation of our study, six lignans and tow norlignans chemical constituents were isolated from the heart of Chamaecyparis formosensis. The cytotoxic activity of these compounds were tested in vitro against promyelocytic leukemia cells（HL-60）and hepatoma cells（Hepa-G2）cell lines. Among them, compound (7’S) – 7,7’ – dihydrotaiwanin C is first time isolated from the nature. It showed significant cytotoxic activity against HL-60 cell lines in vitro. Its IC50 is 1.74 ug/mL after acting only on one day.

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46

Wang, Sheng-Yang, i 王升陽. "Extractives, Discoloration Mechanisms and Protection Methods of Taiwania Heartwood". Thesis, 1999. http://ndltd.ncl.edu.tw/handle/03805475192755224868.

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博士
國立臺灣大學
森林學研究所
87
Abstract Taiwania (Taiwania cryptomerioides Hayata) is an economically important tree species indigenous to Taiwan. Its heartwood is yellowish red with distinguished purplish pink streaks, which fascinates Taiwanese very much. For its excellent decay resistance and well processing properties, Taiwania is one of the five useful coniferous trees in Taiwan. Unfortunately, the color of Taiwania heartwood is susceptible to change to dull black after exposure it to natural environment. This discoloration is an adverse problem that decreases the value of Taiwania products. Therefore, to identify the color compounds of Taiwania heartwood and to illustrate the mechanism of discoloration should facilitate to find an appropriate method to prevent its discoloration. Following by TLC, CC, HPLC, several color constituents, such as taiwanin A (orange), ferruginol (yellow), T-cadinol (yellow), hinokinin (yellow), helioxanthin (yellow), savinin (yellow), pluviatolide (red), were isolated from the methanol extractives of Taiwania heartwood. According to the results of light irradiation experiments, whether in chloroform or acetone, deep orange crystalline taiwanin A was converted into white taiwanin C and pale yellow taiwanin E. Based on the results obtained it is obvious that the discoloration, generating from the photolysis of Taiwanin A, could be one of the reasons to cause the disappearance of yellowish red color of Taiwania heartwood. In addition, some of colorless constituents, such as secoabietane dialdehyde, changed to dark color after light irradiation. To preserve the yellowish red color of Taiwania heartwood, aliphatic polyurethane clear coatings containing Tinuvin photostabilizer coupled with pretreatments using photostabilizers, polyethylene glycol, semicarbazide, salol photostabilizer and acetic acid, were examined. Results demonstrated that discoloration on the surface of Taiwania heartwood was inhibited by pretreating it with photostabilizers (Tinuvin-1130 and Tinuvin-292) or PEG or SCB or salol photostabiloizer, followed by finishing it with an aliphatic polyurethane coating containing Tinuvin-1130 photostabilizer.

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47

Huang, Yu-Hao, i 黃煜豪. "Bioactive Components Isolated from Heartwood of Cinnamomum osmophloeum Kanehira". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/54345287027194582869.

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碩士
國立中興大學
化學系所
96
Cinnamomum osmophloeum Kaneh. (Lauraceae) is an arbor indigenous to Taiwan. As we investigated the chemical constituents of heartwood of C. osmophloeum, a totally 10 compounds including seven lignanoid(A, B, C – G)、one steroid (J)、two flavanoid (H, I) were isolated and identified. Their structures were elucidated to be (7’S, 8’R, 8R)-lyoniresinol-9-O-(E)-feruloyl ester (A)、(7’S, 8’R, 8R)-lyoniresinol-9,9’-di-O-(E)-feruloyl ester (B)、(＋)-lyoniresinol 2α-β-D-xylopyranoside (C)、(－)-lyoniresinol 2α-β-D-xylopyranoside (D)、(－)-secoisolariciresinol (E)9,9’-di-O-feruloyl-(＋)-5,5’-dimethoxy secoisolariciresinol (F)、(＋)-syringaresinol (G)、(－)-catechin (H) 和 (－)-epicatechin (I)、β-sitosterol (J) on the basis of spectroscopic analysis. Among these identified compounds A, B and F are new. In aspect of qualitative analysis of ethanolic extracts of C. osmophloeum five compounds (－)-catechin (H)、(－)-epicatechin (I)、lyoniside (C)、(＋)-syringaresinol (G)、4''-hydroxy-5, 7, 3''-trimethoxyflavan-3-ol were confirmed. In addition, results of biological tests indicated that compound A and B show cytotoxic activity against HepG2, Hep3B and Ca9-22 cancer cell lines.

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48

Lourenço, Ana Carina dos Santos. "The influence of Eucalyptus globulus heartwood in pulp production". Master's thesis, 2008. http://hdl.handle.net/10400.5/1080.

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Mestrado em Engenharia Florestal e dos Recursos Florestais - Instituto Superior de Agronomia
A 18-year-old Eucalyptus globulus tree was used to study the influence of heartwood and sapwood in kraft pulping along different reaction times (1 to 95 min). Heartwood had more extractives (9.8 % vs. 3.9 %) and more xylose content (17.5 % and 13.7 %) compared to sapwood, but no differences were found in total lignin content (23.5 % vs. 24.3 %). After 95 min, heartwood pulps had lower yields (52.4 % vs. 56.7 %) and higher residual lignin content (3.0 % vs. 1.2 %) but no differences were found in sugar content. Sapwood pulps presented higher luminosity (L*, 65 to 80), but no differences at a* and b* values. Two models of delignification kinetics were applied: consecutive and simultaneous. Both models explained well the delignification kinetics of sapwood but the simultaneous model explained better the heartwood delignification. RESUMO ALARGADO Neste trabalho foi usada madeira de Eucalyptus globulus com 18 anos para estudar a influência do cerne e do borne na deslenhificação kraft (170ºC) ao longo de vários tempos de reacção (1 a 95 min). As fracções 20-40 mesh de borne e cerne foram caracterizadas por parâmetros químicos e ópticos. O cerne apresentou maior conteúdo em extractivos (9,8 % vs. 3,9 %), mas idêntico teor em lenhina total (23,5 % vs. 24,3 %) e apresentou uma percentagem mais elevada de xilose em relação ao borne (17,5 % vs. 13,7 %), enquanto o conteúdo em glucose foi superior neste último (81,1 % e 75,1 %). O cerne é mais amarelo que o borne respectivamente, 17 e 14, não apresentando diferenças nos parâmetros L* (83) e a* (3). A madeira de borne, por conter menor teor em extractivos comparativamente ao cerne, apresentou após 95 min de deslenhificação, rendimentos superiores (56,7 % vs. 52,4 %) e menor teor em lenhina residual respectivamente, 3,0 % e 1,2 %. O conteúdo em açucares totais foi semelhante em ambas as amostras: arabinose (0,5 %), manose (1,7 %) e galactose (0,8 %), glucose (84 %) e xilose (13 %). O borne apresentou valores de luminosidade (L*) mais elevados que o cerne, respectivamente, 66,5 e 74,5, não se verificando diferenças quanto aos parâmetros a* e b*. Foram aplicados dois modelos matemáticos baseados numa cinética de 1ª ordem, para explicar a remoção de lenhina. O modelo consecutivo descreveu a reacção de deslenhificação em duas fases: uma fase principal (que nas condições usadas inclui a fase inicial) mais rápida e onde é removida a maior parte da lenhina e uma fase residual, mais lenta. Quando aplicado ao borne, este modelo explicou na fase principal maior extracção de lenhina comparativamente ao cerne (86,0 % vs. 80,0 %), com uma constante de velocidade superior no borne (k = 0,061 min-1 vs. k = 0,048 min-1); na fase residual a extracção foi de respectivamente, 9,0 % e 7,0 % do total de lenhina, com constantes de velocidades correspondentes a 0,017 e 0,007 min-1, permanecendo no cerne cerca de 13,0 % de lenhina na matriz lenhocelulósica e no borne apenas 5,0 %. O modelo simultâneo mostrou a existência de duas fracções da lenhina com diferente reactividade, uma mais reactiva e outra menos reactiva. O borne mostrou 76,0 % da lenhina mais reactiva (L1) que foi removida a uma constante de velocidade k1 de 0,077 min-1, sendo a remoção de 24,0 % da lenhina menos reactiva (L2) feita a um k de 0.018 min-1. No cerne estas fracções representaram respectivamente, 71,0 % e 29,0 %, que apresentaram respectivamente constantes de velocidade: k1 = 0,080 min-1 e k2 = 0,010 min-1. Ambos os modelos explicaram bem a deslenhificação do borne (SQR = 0,041 vs. 0,033), enquanto que o modelo simultâneo explicou melhor a deslenhificação do cerne (SQR = 0,0030). Em conclusão, o cerne foi mais difícil de deslenhificar supondo-se que devido a diferenças anatómicas e químicas

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49

Pan, Shin-Hung, i 潘信鴻. "The Genetic Analysis of Heartwood Related Traits in Taiwania cryptomerioides". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/h737fb.

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碩士
國立中興大學
森林學系所
104
Taiwania (Taiwania cryptomerioides Hayata) is a gymnosperm species indigenous to Taiwan. Its wood is highly resistance to pests, diseases and wind. Due to these excellent wood properties, it is used to make furniture or as building materials. Recent, studies also showed that the heartwood of Taiwania contains specific secondary metabolites with antibacterial and antitumor effect, and therefore have great potential in medical applications. In this study, we collected 171 clonal samples from 35 genotypes of four provenances (Guanshan, Chudong, Dashueshan, Dajia) in the Tsuyunshan T. cryptomerioides seed orchard to evaluate the broad-sense heritability (H2) of traits related to heartwood transition and yield of specific secondary metabolites. We used soft X-ray to analyze sapwood rings number and sapwood length, and used Nuclear Magnetic Resonance (NMR) and Liquid chromatography–mass spectrometry (LC-MS) to identify and quantify the abundance of specific secondary metabolites in the heartwood. The results showed high broad-sense heritability for sapwood ring number (H2=0.68), sapwood length (H2=0.575) and DBH (H2=0.676). The NMR results showed that among all integrated signal regions, those corresponded to the lignans were the ones with broad-sense heritability lager than 0.1. The results were further verified using LC-MS for the six major lignans. Except taiwanin A and taiwanin C, hinokinin (H2=0.82)、savinin (H2=0.88)、helioxanthin (H2=0.91) have high broad-sense heritability, suggest that the heatwood transistion and the biosynthesis of major lingans in Taiwania are regulated by few genes of great effect. The single-nucleotide polymorphism (SNP) in the transcribed genes in developing xylem, bark and needles were evaluated for the 35 Taiwania genotypes using RNA-seq. These 35 genotypes were divided into 6 groups based on their provenance origin and numbers of genotypes. The results showed that the average distance between SNPs is between 58.54 - 63.53 nt, nucleotide diversity (π) is between 0.0084-0.0086 and haplotype diversity (Hd) is between 0.197-0.239. The results suggest that Taiwania has high genetic diversity among genotypes and provenances. The results of this research provide the foundations for association genetics studies using SNP markers and functional genomics analysis through differential gene expression analysis. The identification of genes regulate the transition of heartwood and the abundance of specific secondary metabolites would be crucial for future genetic improvement of related heartwood traits.

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50

Chen, Jeng-Chung, i 陳正忠. "Studies on the Chemical Constituents of the Chamaecyparis formosensis Heartwood". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/58855725993370787377.

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碩士
國立中興大學
化學系所
96
Chamaecyparis formosensis Matsum is indigenous species growing at altitudes of 1,500~2150 meters in Taiwan. The wood of this tree is one of the best building materials in Taiwan. The methanol extract from the heartwood of C. formosensis was concentrated to obtain a residue, and then partitioned between ethyl acetate and H2O. Eleven compounds were isolated from ethyl acetate layer using column chromatography on silica gel, preparative thin layer chromatography and high performance liquid chromatography (HPLC). The eleven compounds includes two sesquiterpenoids (4α-Hydroxy-4β-methyldihydrocostol and Cryptomeridiol ), one diterpenoid (Hinokiol), three lignans (Savinin、 TaiwaninC and Taiwanin E), five norlignans (Hinokiresinol、Agatharesinol、Methyl-yateresinol, Yateresinol and 4α-Hydroxy-4β-methyldihydrocostol-yateresinol). The structure of Methylyateresinol and 4α-Hydroxy-4β-methyldihydrocostol-yateresinol were elucidated on the basis of spectroscopic analysis and were for the first time isolated from nature.

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