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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efeito do estresse hídrico sobre a locomoção e morfologia de girinos de Leptodactylus fuscus e Physalaemus nattereri / Effect of hydric stress on locomotion and morphology in tadpoles of Leptodactylus fuscus e Physalaemus nattereri.

Venturelli, Diego Pimentel 01 March 2016 (has links)
Diversas espécies de anuros da família Leptodactylidae se reproduzem em corpos dágua sazonais, temporários e mantidos exclusivamente por chuvas. Em períodos de estiagem prolongada a poça pode secar completamente, ocasionando elevadas taxas de mortalidade de ovos e girinos dessas espécies, podendo exercer forte pressão seletiva na evolução de mecanismos de resistência e sobrevivência nas fases iniciais do desenvolvimento. Algumas espécies de girinos conseguem sobreviver cerca de cinco dias fora dágua o que pode proporcionar uma adaptação vantajosa, porque possibilita a sobrevivência dos girinos por um período que pode ser suficiente para a reincidência de novas chuvas e restabelecimento do corpo dágua. Apesar dessa capacidade de sobrevivência, pouco se sabe sobre as possíveis modificações que a desidratação pode causar na locomoção e na morfologia durante o desenvolvimento desses animais. O presente trabalho teve como objetivo avaliar o efeito do estresse hídrico: (1) no nível de sobrevivência e perda de massa corpórea; (2) no desempenho locomotor; (3) na morfologia externa (morfometria linear) e interna, analisando tanto o volume total quanto o volume visceral (estereologia); e (4) no tempo até metamorfose após o estresse. Utilizamos girinos de duas espécies de anuros, Leptodactylus fuscus (Leptodactylinae) e Physalaemus nattereri (Leiuperinae), ambas as espécies se reproduzem em corpos dágua temporários, em áreas com estação seca definida estando, portanto sujeitas as mesmas pressões seletivas. Além disso, as duas espécies apresentam modos reprodutivos diferentes, podendo apresentar diferentes graus de resistência ao estresse hídrico. Os girinos das duas espécies foram divididos em dois grupos, os que ficaram em água (grupo controle) e os que foram submetidos ao estresse hídrico (grupo tratamento), por três períodos de tempo (12, 24 e 72 horas). Houve diferenças significativas para valores de perda de massa entre os grupos controle e tratamento em ambas as espécies, sendo o grupo tratamento que mais perdeu massa corpórea em todos os períodos, além disso, quase metade dos girinos de P. nattereri morreram em 36 horas de estresse. Não houve diferenças significativas para os dados de desempenho locomotor e volume total entre os grupos testado para girinos de L. fuscus, mas houve diferenças morfometricas significantes nos componentes relacionados a cauda e no volume visceral, onde, o intestino do grupo tratamento foi menor que do controle. Já em P. nattereri, houve diferenças significativas entre os grupos testados para desempenho locomotor, volume total, morfometria da cauda e volume visceral, sendo o estomago e anexo do tratamento maior que do controle. Nossos resultados sugerem que a exposição ao estresse hídrico não afeta significativamente a morfologia e o desempenho locomotor dos girinos de L. fuscus. No entanto, girinos de P. nattereri apresentaram uma sensibilidade ao estresse hídrico prolongado, principalmente sobre o seu desempenho locomotor. / Several species of frogs (Leptodactylidae) breed in temporary pools maintained exclusively by rainfall. These pools easily dry out causing high mortality of eggs or tadpoles thereby possibly exerting strong selective pressure on the evolution of resistance mechanisms and survival in the early stages of development. However, the tadpoles of some species can survive up to five days in pools that are drying out, needing only a humid substrate for development which can provide an advantageous adaptation, because it enables the survival of tadpoles for a period that may be enough for the recurrence of new rains and restoration of the water body. Despite this ability to survive out of water, it is not known which possible damages dehydration stress causes in tadpoles during their ontogeny. The aim of this study was to evaluate the effect of hydric stress on: (1) the level of survival and weight loss; (2) locomotor performance; (3) external (linear morphometry) and internal morphology, analyzing the total volume and visceral volume (stereology); and (4) the time of development after stress. We used tadpoles of two species, Leptodactylus fuscus (Leptodactylinae) and Physalaemus nattereri (Leiuperinae), both species breed in temporary ponds in areas with well-defined dry season therefore these species are subject to the same selective pressure. In addition, the two species show different reproductive modes, and may possess different degrees of resistance to water stress. To this end, the tadpoles were divided into two groups, those who stayed in 100 ml of water (control group) and those that were subjected to hydric stress (treatment group) for three time periods (12, 24 and 72 hours). Significant differences for weight loss were found between the groups (control/treatment) in both species, with the treatment group losing more weight in all stress levels. Furthermore almost half of P. nattereri tadpoles died within 36 hours of stress. There was no significant difference for locomotor performance and total volume between control group and treatment group of L. fuscus tadpoles, but morphometric analyses indicated a significant difference in the components related to tail and visceral volume, with the gut of the treatment group was lower than the control. In P. nattereri tadpoles, there were significant differences between the groups tested for locomotor performance, total volume, tail morphometry and visceral volume, with the stomach of the treatment group being greater than in the control group. Our results suggest that hydric stress has a significant effect on locomotion and morphology of P. nattereri tadpoles, but not in L. fuscus.
2

Efeito do estresse hídrico sobre a locomoção e morfologia de girinos de Leptodactylus fuscus e Physalaemus nattereri / Effect of hydric stress on locomotion and morphology in tadpoles of Leptodactylus fuscus e Physalaemus nattereri.

Diego Pimentel Venturelli 01 March 2016 (has links)
Diversas espécies de anuros da família Leptodactylidae se reproduzem em corpos dágua sazonais, temporários e mantidos exclusivamente por chuvas. Em períodos de estiagem prolongada a poça pode secar completamente, ocasionando elevadas taxas de mortalidade de ovos e girinos dessas espécies, podendo exercer forte pressão seletiva na evolução de mecanismos de resistência e sobrevivência nas fases iniciais do desenvolvimento. Algumas espécies de girinos conseguem sobreviver cerca de cinco dias fora dágua o que pode proporcionar uma adaptação vantajosa, porque possibilita a sobrevivência dos girinos por um período que pode ser suficiente para a reincidência de novas chuvas e restabelecimento do corpo dágua. Apesar dessa capacidade de sobrevivência, pouco se sabe sobre as possíveis modificações que a desidratação pode causar na locomoção e na morfologia durante o desenvolvimento desses animais. O presente trabalho teve como objetivo avaliar o efeito do estresse hídrico: (1) no nível de sobrevivência e perda de massa corpórea; (2) no desempenho locomotor; (3) na morfologia externa (morfometria linear) e interna, analisando tanto o volume total quanto o volume visceral (estereologia); e (4) no tempo até metamorfose após o estresse. Utilizamos girinos de duas espécies de anuros, Leptodactylus fuscus (Leptodactylinae) e Physalaemus nattereri (Leiuperinae), ambas as espécies se reproduzem em corpos dágua temporários, em áreas com estação seca definida estando, portanto sujeitas as mesmas pressões seletivas. Além disso, as duas espécies apresentam modos reprodutivos diferentes, podendo apresentar diferentes graus de resistência ao estresse hídrico. Os girinos das duas espécies foram divididos em dois grupos, os que ficaram em água (grupo controle) e os que foram submetidos ao estresse hídrico (grupo tratamento), por três períodos de tempo (12, 24 e 72 horas). Houve diferenças significativas para valores de perda de massa entre os grupos controle e tratamento em ambas as espécies, sendo o grupo tratamento que mais perdeu massa corpórea em todos os períodos, além disso, quase metade dos girinos de P. nattereri morreram em 36 horas de estresse. Não houve diferenças significativas para os dados de desempenho locomotor e volume total entre os grupos testado para girinos de L. fuscus, mas houve diferenças morfometricas significantes nos componentes relacionados a cauda e no volume visceral, onde, o intestino do grupo tratamento foi menor que do controle. Já em P. nattereri, houve diferenças significativas entre os grupos testados para desempenho locomotor, volume total, morfometria da cauda e volume visceral, sendo o estomago e anexo do tratamento maior que do controle. Nossos resultados sugerem que a exposição ao estresse hídrico não afeta significativamente a morfologia e o desempenho locomotor dos girinos de L. fuscus. No entanto, girinos de P. nattereri apresentaram uma sensibilidade ao estresse hídrico prolongado, principalmente sobre o seu desempenho locomotor. / Several species of frogs (Leptodactylidae) breed in temporary pools maintained exclusively by rainfall. These pools easily dry out causing high mortality of eggs or tadpoles thereby possibly exerting strong selective pressure on the evolution of resistance mechanisms and survival in the early stages of development. However, the tadpoles of some species can survive up to five days in pools that are drying out, needing only a humid substrate for development which can provide an advantageous adaptation, because it enables the survival of tadpoles for a period that may be enough for the recurrence of new rains and restoration of the water body. Despite this ability to survive out of water, it is not known which possible damages dehydration stress causes in tadpoles during their ontogeny. The aim of this study was to evaluate the effect of hydric stress on: (1) the level of survival and weight loss; (2) locomotor performance; (3) external (linear morphometry) and internal morphology, analyzing the total volume and visceral volume (stereology); and (4) the time of development after stress. We used tadpoles of two species, Leptodactylus fuscus (Leptodactylinae) and Physalaemus nattereri (Leiuperinae), both species breed in temporary ponds in areas with well-defined dry season therefore these species are subject to the same selective pressure. In addition, the two species show different reproductive modes, and may possess different degrees of resistance to water stress. To this end, the tadpoles were divided into two groups, those who stayed in 100 ml of water (control group) and those that were subjected to hydric stress (treatment group) for three time periods (12, 24 and 72 hours). Significant differences for weight loss were found between the groups (control/treatment) in both species, with the treatment group losing more weight in all stress levels. Furthermore almost half of P. nattereri tadpoles died within 36 hours of stress. There was no significant difference for locomotor performance and total volume between control group and treatment group of L. fuscus tadpoles, but morphometric analyses indicated a significant difference in the components related to tail and visceral volume, with the gut of the treatment group was lower than the control. In P. nattereri tadpoles, there were significant differences between the groups tested for locomotor performance, total volume, tail morphometry and visceral volume, with the stomach of the treatment group being greater than in the control group. Our results suggest that hydric stress has a significant effect on locomotion and morphology of P. nattereri tadpoles, but not in L. fuscus.
3

Morfološka varijabilnost vrsta roda Anacamptis Rich. (Orchidoideae, Orchidaceae) na području Balkanskog poluostrva i Panonske nizije / Morphological variability of species of the genusAnacamptis Rich. (Orchidoideae, Orchidaceae) in the Balkan Peninsula and the Pannonian Plain

Radak Boris 04 November 2019 (has links)
<p>Pored rodova evropskih orhideja koji se odlikuju velikim stepenom diverzifikacije, kao i značajnim brojem novoopisanih vrsta, kao &scaron;to su <em>Ophrys </em>ili<em> Epipactis,</em> rod<em> Anacamptis </em>je ostao poprilično zapostavljen u orhidolo&scaron;kim istraživanjima. Na predstavnicima ovog roda uglavnom su vr&scaron;ena molekularna istraživanja, u kojima je bio uključen i veći broj drugih rodova.Takođe, urađene su i opsežne studije, ali samo na pojedinim vrstama. Morfolo&scaron;ka istraživanja su bila veoma retka i uz par uzuzetaka, ograničena na geografski mala područja i na jednu ili nekoliko morfolo&scaron;ki sličnih vrsta. Analiza morfolo&scaron;ke varijabilnosti ovolikog broja taksona roda<em> Anacamptis</em> na geografski relativno velikom području kakvo je Balkansko poluostrvo, kao i deo Panonske nizije koji se oslanja na njega, do&nbsp; sada nije bilo sprovedeno. Morfolo&scaron;kim analizama bili su podvrgnuti gotovo svi predstavnici ovog roda u rangu vrste i podvrste, a koji se javljaju na području kopnenog dela Balkanskog poluostrva, kao i južnog oboda Panonske nizije. Sprovedene su jednostrane i uporedne morfolo&scaron;ke analize sa detaljnomobradom podataka metodama bazične, univarijantne i multivarijantne statistike. Do sada najvećim istraživanjem taksona roda<em> Anacamptis</em>, po broju obrađenih jedinki i području na kom je sprovedeno, bila je obuhvaćena 2001 jedinka iz 185&nbsp; populacija. Analizirane su prirodne populacije, ali i materijal iz Herbarijuma BUNS. Ukupno je definisano 69 morfolo&scaron;kih karaktera, kvantitativnih i kvalitativnih, a među njima su traženi oni koji imaju potencijalno diferencijalni karakter između opisanih vrsta i infraspecijskih taksona. Analize su obuhvatile i interpopulacionu morfolo&scaron;ku varijabilnost u okviru svakog taksona, a u cilju uočavanja postojanja određenih geografskih obrazaca njenih promena. Morfolo&scaron;ki karakteri koji su se u sprovedenim analizama pokazali kao taksonomski informativni, iskori&scaron;ćeni su za formiranje dihotomog ključa za determinaciju taksona roda <em>Anacamptis</em> prisutnih na istraživanom području. Analizama je utvrđen veliki broj karaktera koji su statistički značajno različiti između analiziranih populacija, podvrsta i vrsta. Većina karaktera je pokazala umerenu ili nisku varijabilnost, a u retkim slučajevima i povećanu. Karakteri cveta međusobno su statistički značajno korelisani,većina slabo do umereno, dok su oni na listićima kacige, kao i između labeluma i drugih delova cveta jako do izrazito jako povezani. Jedini takson koji nije pokazao nikakvu infraspecijsku diferencijaciju, a koji se odlikuje velikom unutari interpopulacionom varijabilno&scaron;ću je<em> A. pyramidalis</em>. Iz istog razloga je pokazano kao neosnovano izdvajanje jedinki iz različitih delova njegovog areala u do sada opisane infraspecijske oblike. Potvrđena je niska morfolo&scaron;ka varijabilnost uskorasprostranjene vrste <em>A. boryi.</em> Kod svih preostalih istraživanih taksona utvrđeno je postojanje određenih obrazaca geografske interpopulacione varijabilnosti i infraspecijske struktuiranosti.Populacije <em>A. laxiflora</em> subsp. <em>laxiflora </em>mogu se podeliti na jadranske i kontinentalne, pri čemu najzapadnije pokazuju i najmanje vrednosti analiziranih karaktera. <em>A. coriophora </em>subsp.<em> fragrans </em>se pokazala kao manje varijabilnom od tipske podvrste, ali je u okviru nje kao zaseban takson izdvojen var. <em>hermae </em>kao fenolo&scaron;ki, ekolo&scaron;ki i morfolo&scaron;ki odvojen u odnosu na ostaleispitivane populacije. Tipska podvrsta pokazuje obrazac variranja ukupne morfolo&scaron;ke varijabilnosti u pravcu zapad-istok. Kao karakteri koji su najznačajniji za diferencijaciju podvrsta vrste<em> A. palustris</em> izdvojeni su dužina i &scaron;irina brakteje, stepen diferenciranosti labeluma na režnjeve, kao i dubina sinusa koja ih razdvaja. Populacije<em> A. palustris</em> subsp. <em>elegans</em> moguće je podeliti na tri geografski i morfolo&scaron;ki definisane grupe &ndash; istočnobalkansku, zapadnobalkansku i periferne populacije sa severa Srbije i iz Slovenije. Kao diferencijalni karakteri između taksona sekcije <em>Laxiflorae</em> pokazali su se odnos između dužine plodnika i brakteje, kao i dužina srednjeg režnja labeluma. Vrsta<em> A. morio </em>je po prvi put jasno morfolo&scaron;ki i arealno podeljena na dve podvrste na istraživanom području. Podvrste pokazuju velika preklapanja vrednosti morfolo&scaron;kih karaktera, ali se obe odlikuju specifičnim karakteristikama cveta, pre svega labeluma na osnovu kojih ih je moguće razlikovati. Definisani su areali podvrsta<em> A.morio </em>na istraživanom području &ndash; tipska podvrsta je prevashodno severnija i zapadnija, dok je subsp.<em> caucasica </em>južnija i istočnija. Prvu odlikuju krupniji cvetovi, bubrežastih labeluma sa srednjim režnjem koji ne prevazilazi značajno dužinu bočnih, dok je druga sa sitnijim cvetovima i snažno isturenim srednjim režnjem. Obe podvrste mogu se podeliti na grupe populacija sa jasno definisanim geografskim raspostranjenjem. Vrsta <em>A. papilionacea </em>je po prvi put morfolo&scaron;ki istaživana na većem broju primeraka, a ne prostim poređenjem pojedinačnih primeraka iz različitih delova areala. Pokazana je morfolo&scaron;ka diferenciranost na dve podvrste &ndash; tipsku i subsp. aegaea, koje se jasno morfolo&scaron;ki razlikuju i zauzimaju različite delove areala vrste. U okviru subsp. <em>papilionacea</em> registrovan je klinalni raspored morfolo&scaron;ke varijabilnosti u pravcu sever-jug. Registrovana su i tri hibrida, nova za područje pojedinih zemalja &ndash; A. <em>&times; gennarii</em> (Severna Makedonija),A. <em>&times; parvifolia</em> (Crna Gora) i A. &times; <em>timbali</em> (Srbija). Hibridi pokazuju generalnu morfolo&scaron;ku intermedijarnost u odnosu na roditelje, ali se odlikuju i novim stanjima karaktera, nezabeleženim kod roditeljskih taksona. Slični obrasci morfolo&scaron;ke varijabilnosti, kako na interpopulacionom nivou pojedinih vrsta, ali iizmeđu podvrsta svake istraživane vrste, pokazuju jasnu vezu između istraživanih taksona i jo&scaron; jednom opravdavaju njihovo zajedničko grupisanje u rod<em> Anacamptis.</em></p> / <p>Unlike the highly diversified and species-rich genera of European orchids, such as<em> Ophrys </em>or <em>Epipac</em>tis, the genus <em>Anacamptis </em>has remained quite neglected in orchidological research. Representatives of this genus, together with many others genera, were investigated mainly by molecular methods. Also, extensive studies have been done, but only on specific species. Morphological studies were very rare, and with a few exceptions, limited to geographically small areas and one or more morphologically similar species. Analysis of the morphological variability of so many taxa of the genus <em>Anacamptis</em>, in a is, in a geographically relatively large area such as the Balkan Peninsula, as geographically relatively large area such as the Balkan Peninsula, as well as the southern part of the Pannonian Plain, has not been conducted so far. Morphological analyses were<br />performed on almost all representatives of this genus,in the species and subspecies rank , occurring in the Balkan Peninsula mainland, as well as in the southern perimeter of the Pannonian Plain. Comparativemorphological analyses were conducted using the methods of basic, univariate and multivariate statistics.So far, the largest study of the genus&nbsp; nacamptis, by the number of processed individuals and the area in which it was conducted, included 2001 individuals from 185 populations. Natural populations and&nbsp; material from the BUNS Herbarium were analyzed. A total of 69 morphological characters, quantitative and&nbsp; qualitative, were defined, and those that have a potentially differential character among analyzed species and infraspecific taxa were selected. The analyzes also included interpopulation morphological variability within each taxon, to identify the existence of specific geographic patterns of its changes. The morphological characters that proved to be taxonomically informative, were used to form the dichotomous key for the determination of the genus Anacamptis members, presented in the study area. The analyzes identified a large number of characters that were statistically significantly different between the analyzed populations, subspecies, and species. Most of the characters showed moderate or low variability, and in rare cases increased variability. Flower&rsquo;s characters were statistically significantly correlated with each other, most of them weakly to moderately, while those of the sepals and petals, as well as between the&nbsp; labellum and other parts of the flower, were very strongly correlated. The only taxon that has not shown any infraspecific differentiation (except <em>A. boryi</em>), and which is characterized by high intra- and interpopulation variability, is A. pyramidalis. For the same reason, it has been shown as unjustified to separate individuals from different parts of species range into infraspecific forms. The low morphological variability of the narrowly distributed A. boryi was confirmed. In all other taxa studied, the existence of certain patterns of geographical interpopulation variability and infraspecific structuring was detected. <em>A. laxiflora</em> subsp. <em>laxiflora</em> populations can be divided into two groups &ndash; Adriatic and Continental, with the lowest characters values measured among the westernmost populations. <em>A. coriophora s</em>ubsp. <em>fragrans</em> proved to be less variable than the type subspecies, but within it, a new variety (var. hermae) as phenological, ecological and morphologically distinct from other studied populations was described. The typesubspecies has a transition of morphological variability in a west-east direction. The characters that are the most important for differentiation of A. palustris subspecies are the&nbsp; bract length and width, the degree of labellum differentiation into lobes, and the depth of the sinuses that separate them. Populations of A. palustris subsp. elegan<em>s </em>can be divided into three geographically and morphologically defined groups &ndash; Eastern Balkan, Western Balkan and peripheral populations from the North Serbia and Slovenia. Differential characters&nbsp; among the Laxiflorae section taxa are ration between the ovary length and bract length, as well as the labellum middle lobe length. For the first time, species <em>A. morio </em>is morphologically and geographically divided into two subspecies, in the&nbsp; study area. Analyzed subspecies have great overlapping values for many morphological characters, but both are characterized by specific flower&rsquo;s characteristics, above all labellum shape. On this basis, it is possible to distinguish them. Areals of <em>A</em>. <em>morio </em>subspecies were defined &ndash; the type subspecies is predominantly northern and western,while subsp. caucasica is southern and eastern. The first is characterized by larger flowers, renal shape labellum with a median lobe that does not exceed significantly the length of the lateral ones, while the second subspecies has smaller flowers and strongly projecting the median lobe. Both subspecies can be divided into groups of populations that have clearly defined geographical distribution. For the first time, A. papilionacea was morphologically investigated on a larger number of specimens, unlike previous&nbsp;&nbsp; researches in which individual specimens from different parts of the range were simply compared. Morphological differentiation into two subspecies was shown &ndash; type and subsp. aegaea. They are morphologically distinct and occupy different parts of the species range. Within the subsp. papilionacea a clinal distribution of morphological variability in the north-south direction was recorded. Three taxa of hybrid origin, new for the area of North Macedonia (A.<em> &times; gennari</em>i), Montenegro (A. <em>&times; parvifolia</em>) and Serbia (A. &times; t<em>imbali</em>) were registered. Hybrids exhibit a general morphological intermediacy between parents but are also distinguished by new character states that were not observed in<br />parental taxa. Similar patterns of morphological variability, both at the interpopulation level ofindividual species and between the subspecies of each species studied, show a clear relationship between the studied taxa and once again justify their grouping into the genus <em>Anacamptis.</em></p>

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