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Tracking coherences in a dissipative ocean analysing and controlling Br2/Ar matrixIbrahim, Heide Nadda January 2008 (has links)
Zugl.: Berlin, Freie Univ., Diss., 2008
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MAPON-Untersuchungen am System 82BrFeTramm, Christian. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2004--Bonn.
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Laserinduzierte Plasma-Emissionsspektrometrie für die Online-Charakterisierung der Schwermetall- und Halogenbelastung technischer Kunststoffe /Stepputat, Michael. January 2008 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2008.
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Adulte hippocampale Neurogenese bei psychischen Erkrankungen / Adult hippocampal neurogenesis in psychiatric deseasesFinger, Mathias Johannes January 2007 (has links) (PDF)
Es existiert bereits eine Vielzahl von tierexperimentellen Studien bezüglich Einflussfaktoren auf die adulte Neurogenese. Nachdem die Teilungsfähigkeit von neuralen Stammzellen Ende der 1990er Jahre auch im adulten humanen Gehirn nachgewiesen wurde, war es das Ziel der vorliegenden Arbeit, adulte Neurogenese bei psychischen Erkrankungen zu quantifizieren bzw. den Ein-fluss medikamentöser Therapien auf die adulte Neurogenese zu untersuchen. Diese Studie stellt dabei die bislang einzige Arbeit dar, die sich mit der humanen adulten Neurogenese bei psychischen Erkrankungen beschäftigt. Mittels Doppelfärbungen von Ki67 und BrdU an Mausgewebe wurde zunächst nachgewiesen, dass das Ki67-Antigen ein zuverlässiger Marker für sich teilende Zellen ist, woraufhin die Färbeprozedur problemlos auf Humangewebe übertragen werden konnte. Die Quantifizierung von Ki67 positiven Zellen erfolgte entlang der Körnerzellschicht in einem definierten Abstand in der Einheit Zellen pro Millimeter. Die Ergebnisse der hier vorliegenden Studie widersprechen in mehrfacher Hinsicht den Hypothesen, die sich aus tierexperimentellen Studien ergeben. Während die neurale Stammzellproli-feration bei schizophrenen Psychosen signifikant vermindert ist, findet sich kein Unterschied bei affektiven Erkrankungen im Vergleich zu Kontrollen. Weder wird die „Neurogenese-Hypothese“ der Depression bestätigt, noch zeigte sich ein Effekt antidepressiv oder antipsychotisch wirksamer Pharmaka auf die Rate adulter Neurogenese, da eine pharmakologische Therapie jedweder Art keinen Einfluss auf die Zahl Ki67 positiver Zellen hatte. Deshalb scheint eine Steigerung der adulten Neurogenese kein Wirkmechanismus dieser Medikamente zu sein. Ein überraschendes Ergebnis jedoch ist die signifikant reduzierte Rate adulter Neurogenese bei an Schizophrenie erkrankten Patienten. Aufgrund der sehr begrenzten Anzahl untersuchter Patienten ist die vorliegende Studie in ihrer Aussagekraft jedoch eingeschränkt und muss daher an einem größeren Patientenkollektiv wiederholt werden. Eine Vielzahl von Fragen bzgl. des Stellenwerts der adulten Neurogenese bei psychischen Erkrankungen bleibt darüber hinaus weiter ungeklärt, was die Durchführung weiterer Studien am adulten humanen Gehirn verlangt. / The phenomenon of adult neurogenesis (AN), that is, the generation of functional neurons from neural stem cells in the dentate gyrus of the hippocampus, has attracted remarkable attention, especially as it was shown that this process is also active in the human brain. Based on animal studies, it has been suggested that reduced AN is implicated in the etiopathology of psychiatric disorders, and that stimulation of AN contributes to the mechanism of action of antidepressant therapies. As data from human post-mortem brain are still lacking, we investigated whether the first step of AN, that is, the level of neural stem cell proliferation (NSP; as quantified by Ki-67 immunohistochemistry), is altered in tissue from the Stanley Foundation Neuropathology Consortium comprising brain specimens from patients with bipolar affective disorder, major depression, schizophrenia as well as control subjects (n = 15 in each group). The hypothesis was that stem cell proliferation is reduced in affective disorders, and that antidepressant treatment increases NSP. Neither age, brain weight or pH, brain hemisphere investigated nor duration of storage had an effect on NSP. Only in bipolar disorder, postmortem interval was a significant intervening variable. In disease, onset of the disorder and its duration likewise did not affect NSP. Also, cumulative lifetime dose of fluphenazine was not correlated with NSP, and presence of antidepressant treatment did not result in an increase of NSP. Concerning the different diagnostic entities, reduced amounts of newly formed cells were found in schizophrenia, but not in major depression. Our findings suggest that reduced NSP may contribute to the pathogenesis of schizophrenia, whereas the rate of NSP does not seem to be critical to the etiopathology of affective disorders, nor is it modified by antidepressant drug treatment.
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DFT-Studien zu Mechanismus und Delokalisation in organischen Reaktionen und MolekülenPapafilippopoulos, Andrea. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2002--Braunschweig.
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Aspectos bioecol?gicos da culicidofauna em unidade de conserva??o no munic?pio de N?sia Floresta, Rio Grande do Norte, BrasilSilva, Jos? Hil?rio Tavares da 30 September 2014 (has links)
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Previous issue date: 2014-09-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Em diversas regi?es do pa?s foram realizados estudos da fauna de culic?deos em ?reas
antropizadas de ambientes variados, urbanos, rurais e florestais. A Floresta Nacional de N?sia
Floresta (FLONA-NF), localizada na regi?o Metropolitana de Natal, ? um remanescente de
Mata Atl?ntica submetida a hist?ricas etapas de antropiza??o. Os fragmentos encontram-se
em lenta regenera??o da mata nativa, portanto apresenta uma heterogeneidade de habitats, o
que permite o desenvolvimento de esp?cies de culic?deos com variados h?bitos hematof?gicos
e comportamentais, tais fatores estimularam a realiza??o do presente estudo na unidade de
conserva??o. Os estudos com culic?deos permitem tamb?m avaliar o grau de altera??o
ambiental em algumas regi?es. Esses insetos participam das cadeias epidemiol?gicas de
doen?as com distribui??o geogr?fica extensa e ocorr?ncia em grandes grupos populacionais,
tornando necess?rio o conhecimento das caracter?sticas biol?gicas das esp?cies com a
finalidade de se conhecer pontos vulner?veis que facilitem o controle dos insetos vetores.
Com o objetivo de realizar o primeiro levantamento de culicideos na ?rea preservada de N?sia
Floresta foram realizadas coletas mensais de mosquitos adultos e imaturos por meio de quatro
procedimentos metodol?gicos, coletas com armadilha Shannon, aspirador de Nasci, em
brom?lias e larvitrampas entre fevereiro de 2013 e fevereiro de 2014. Foram coletados e
identificados morfologicamente por meio de chaves entomol?gicas de identifica??o
espec?fica, 8.299 indiv?duos, com a seguinte distribui??o: 7.677 mosquitos adultos coletados
na armadilha Shannon; 397 mosquitos capturados por meio de aspirador el?trico de Nasci; 93
e 132 mosquitos imaturos em larvitrampas e brom?lias respectivamente. Entre os culic?deos
foram encontrados nove g?neros com 19 esp?cies e 3 g?neros sem identifica??o da esp?cie. O
presente estudo mostra-se relevante por ser o primeiro estudo realizado no local, com registro
de ocorr?ncia de esp?cies no Rio Grande do Norte; pelo acr?scimo de informa??es sobre a
ecologia dos culicideos e por acrescentar conhecimento sobre t?xons com import?ncia m?dica
em outras regi?es do pa?s. Al?m disso, sinaliza para a import?ncia da conserva??o do
fragmento florestal de mata atl?ntica e an?lises acerca da urbaniza??o das ?reas do entorno da
unidade de conserva??o considerando a aproxima??o potencial de hospedeiros invertebrados,
vertebrados e consequentemente a veicula??o de pat?genos com impacto na sa?de p?blica. / Studies on culicid fauna were conducted in anthropized areas of urban, rural and forest
environments in different regions of Brazil. The National Forest of Nisia Floresta (FLONANF),
located in the metropolitan region of Natal, is an Atlantic Forest remnant submitted to
historical stages of anthropization. The fragments are in a stage of slow regeneration of native
forest, exhibiting, therefore, heterogeneity of habitats, which enables the development of
culicid species with varied hematophagic and behavioral habits. These factors stimulated the
present study at the conservation unit. Studies of culicids also allow assessing the degree of
environmental change in a number of regions. These insects participate in the epidemiological
chains of diseases with extensive geographic distribution and occurrence of large population
groups, requiring knowledge of the biological characteristics of species in order to determine
the vulnerable points that facilitate control of vector insects. With the aim of performing the
first culicid survey in the preserved area of Nisia Floresta, monthly collections of adult and
immature mosquitoes were conducted by means of four methodological procedures, using a
Shannon trap and Nasci aspirator in bromelias and larvitraps between February 2013 and
February 2014. A total of 8,299 individuals were collected and identified morphologically
using identification keys. The following distribution was obtained: 7,677 adult mosquitoes
collected in the Shannon trap; 397 mosquitoes captured by the Nasci aspirator; and 93 and
132 immature mosquitoes in larvitraps and bromelias respectively. Nine genera of culicids
were found with 19 species and three genera without species identification. The present study
is relevant for being the first conducted at the site, with the occurrence of species in Rio
Grande do Norte state; for adding knowledge about both the ecology of culicids and taxa with
medical importance in other parts of the country. Furthermore, it highlights the need for
conservation of the Atlantic Forest fragment and analyses regarding urbanization of areas
surrounding the conservation unit, considering the potential presence of vertebrate and
invertebrate hosts and consequent spread of pathogens with an impact on public health.
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Mikrostanovení kobaltu metodami molekulové a atomové absorpční spektrometrie / Microdetermination of cobalt by methods of molecular and atomic absorption spectrometryCharuza, Martin January 2012 (has links)
This diploma thesis is focused on microdetermination of cobalt by UV-VIS spectrophotometry with organic agents and comparison with atomic absorption spectrometry. In the first part properties, occurance and importance of cobalt in the environment are desribed, complete with as a part of vitamine B12. Attention is also given to cobalt compounds, especially in the oxidative states +II and +III. Methods of preconcentration and preparation cobalt determination in real samples are adduced. In this thesis are described some optical analytical methods with accept on spectrophotometric agents for determination of cobalt. The experimental part of this thesis icludes optimalization of the spectrophotometric determination of cobalt with choosen organic agents 4-(2-pyridylazo)resorcin and 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol and optimalization of atomic absorption spectrometry for cobalt determination. All of real samples of water (surface, underground, mineral and waste) were measured by both 4-(2-pyridylazo)resorcin and 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol via UV-VIS and via atomic absorption spectrometry. Results of determinations were compared. A sample of vitamine B12 was measured too by all techniques.
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Caracteriza??o por DNA metabarcoding da biodiversidade de ambientes neotropicais : investiga??o das comunidades presentes em fitotelmos de brom?lias e sedimentos marinhos / DNA Metabarcoding for biodiversity characterization of Neotropical environments : study of bromeliad phytotelmata and marine sediments communitiesSim?o, Taiz Leonor Lopes 21 March 2016 (has links)
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Previous issue date: 2016-03-21 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This project applied the DNA metabarcoding technique, which consists of a large-scale identification of the biodiversity present in a given community (through the total DNA sequencing without the need for isolation and laboratory cultivation) in two underexplored Brazilian environments with high biological diversity. The first is a typical Neotropical microenvironment, called
bromeliad phytotelm, which is formed by the accumulation of water and debris among the leaves of these plants. The bromeliads investigated in this study were sampled in areas of dense ombrophilus forest and mixed ombrophilus forest in southern Brazil (located at the ?Pro-Mata? Research Center), and belonged to the species Aechmea gamosepala Wittmack, Vriesea friburgensis Mez and Vriesea platynema Gaud. The collection comprised multiple individuals per species and also multiple samples (different tanks) from the same individual, making it possible to assess the complexity of the variation in these communities. The second environment consists of marine sediments collected in the Rio Grande Cone (located in southeastern Brazil, in the offshore portion of the Pelotas Basin), at depths of down to 18 meters below the seafloor. The samples originated from four different areas, with different geochemical characteristics and strong indications of the presence of chemosynthetic communities. This study demonstrated the presence of high biodiversity in both environments. We identified 30 prokaryotic phyla and 67 eukaryotic phyla in bromeliad phytotelmata, which seem to include both endemic organisms of this peculiar environment and organisms with ubiquitous distribution, common in freshwater or soil habitats. An interesting feature is that, in some cases, samples from different tanks of the same individual are more similar to tanks of other individuals (and even from other species) than between them. Thus, our results suggest that each bromeliad tank acts as an isolated body of water, where the effects of predation, competition and stochastic events such as wind-borne particles, fecal pellets and liquid excretions of terrestrial animals, dead leaves and animals can largely drive the community composition. Concerning the
marine sediments, we observed the presence of 58 prokaryotic phyla, many of which are present in other chemosynthetic communities. Among these organisms were identified anaerobic methanotrophic archaeal groups and their syntrophic partners (sulfate-reducing bacteria), which together form a consortium with a significant role in the anaerobic oxidation of methane, a very important process that controls the emission of this greenhouse gas into the atmosphere. Statistical analysis performed in both studies sought to describe patterns of diversity of these communities at different spatial scales and to interpret them in the light of current knowledge about these environments. Overall, the results obtained in this thesis reveal in detail the complexity of these communities, opening new ways for further studies focusing on the processes that control their spatio-temporal dynamics. / O presente projeto aplicou a t?cnica de DNA metabarcoding, que visa caracterizar em larga escala a biodiversidade presente em determinada comunidade (atrav?s do sequenciamento do DNA total e sem a necessidade de cultivo ou isolamento), em dois ambientes brasileiros pouco explorados e com grande riqueza de esp?cies. O primeiro ? um microambiente t?pico da regi?o neotropical, denominado fitotelmo de brom?lia, o qual ? formado pelo ac?mulo de ?gua e detritos entre as folhas destas plantas. As brom?lias investigadas neste estudo foram amostradas em ?reas de Floresta Ombr?fila Densa e/ou Mista no sul do Brasil (localizadas no Centro de Pesquisas e Conserva??o da Natureza Pr?-Mata, PUCRS), e pertencem ?s esp?cies Aechmea gamosepala Wittmack, Vriesea friburgensis Mez e Vriesea platynema Gaud. A coleta englobou m?ltiplos indiv?duos por esp?cie e tamb?m m?ltiplas amostras (diferentes cisternas) do mesmo indiv?duo, possibilitando avaliar a complexidade da varia??o nestas comunidades. O segundo ambiente consiste de sedimentos marinhos coletados no Cone de Rio Grande (situado no sudeste do Brasil, na por??o offshore da Bacia de Pelotas), em profundidades de at? 18 metros abaixo do fundo do mar. As amostras s?o provenientes de quatro ?reas distintas, apresentando diferentes caracter?sticas geoqu?micas e fortes ind?cios da presen?a de comunidades quimiossint?ticas. Nossa investiga??o observou grande diversidade biol?gica em ambos os ambientes. Foram identificados 30 filos de procariotos e 67 filos de eucariotos nos fitotelmos de brom?lia, os quais parecem compreender tanto organismos end?micos deste ambiente peculiar como organismos com distribui??o cosmopolita, comuns em habitats de ?gua doce ou solo. Uma caracter?stica interessante ? que, em alguns casos, amostras provenientes de diferentes cisternas do mesmo indiv?duo s?o mais semelhantes a cisternas de outros indiv?duos (e mesmo de outras esp?cies) do que entre si. Desta forma, nossos resultados indicam que cada cisterna atua como um corpo d??gua isolado, onde os efeitos de preda??o, competi??o e eventos estoc?sticos como part?culas carregadas pelo vento, restos de folhas ou animais mortos, bem como excre??es de animais, podem interferir fortemente na composi??o espec?fica da comunidade local. Em rela??o aos sedimentos marinhos, observamos a presen?a de 58 filos procari?ticos, os quais compreendem diversos t?xons j? caracterizados em outras comunidades quimiossint?ticas marinhas. Entre estes organismos, foram identificadas arqueas metanotr?ficas e seus parceiros sintr?ficos (bact?rias redutoras de sulfato), que juntos formam um cons?rcio cujo papel ? fundamental na oxida??o anaer?bica do metano, um importante processo que controla a emiss?o deste g?s de efeito estufa para a atmosfera. An?lises estat?sticas realizadas em ambos os estudos buscaram descrever padr?es de diversidade destas comunidades em diferentes escalas espaciais, bem como interpret?-los ? luz do conhecimento atual sobre estes ambientes. De forma geral, os resultados obtidos nesta tese revelam em detalhe a complexidade destas comunidades, e abrem caminho para estudos mais aprofundados dos processos que controlam sua din?mica espa?o-temporal.
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Herpetofauna associada ? brom?lia rup?cola, encholirium spectabile, no semi?rido brasileiro: revis?o da literatura, ecologia das esp?cies e comportamento de psychosaura agmosticha (squamata: mabuyidae)Jorge, Jaqueiuto da Silva 20 April 2015 (has links)
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Previous issue date: 2015-04-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / As brom?lias constituem importante microhabitat para a herpetofauna, pois s?o
bastante utilizadas como abrigo contra predadores, al?m de sua arquitetura foliar
possibilitar manuten??o de umidade e temperatura relativamente constantes no seu
interior, compondo um ambiente favor?vel para os anf?bios e r?pteis, especialmente em
?reas sob estresse h?drico. No entanto, os estudos que tratam dessa rela??o ainda s?o
incipientes e mais concentrados sobre as brom?lias fitotelmatas acumuladoras de ?gua.
No caso das brom?lias rup?colas n?o fitotelmatas do g?nero Encholirium, que se
desenvolvem em afloramentos rochosos e abrigam esp?cies de regi?es semi?ridas como
as Caatingas, as rela??es animais-plantas s?o praticamente desconhecidas. Nesse
contexto, este estudo teve como objetivos estudar a fauna herpetol?gica habitante das
brom?lias macambiras, Encholirium spectabile, analisando a ocupa??o e uso destas
brom?lias pelos diferentes t?xons, e a ecologia comportamental do largarto Psychosaura
agmosticha, buscando identificar os fatores associadas com esta rela??o estrita em ?rea
de Caatinga. Uma ampla revis?o da literatura mundial acerca do tema lagartos em
brom?lias subsidiou este estudo sob a perspectiva ecol?gica dessa associa??o. O trabalho
de campo foi realizado na Fazenda Tanques, munic?pio de Santa Maria/RN, mesorregi?o
do Agreste potiguar, com as observa??es e/ou coletas diurnas e noturnas efetuadas
mensalmente, durante tr?s dias consecutivos, de Janeiro de 2011 a Agosto de 2012,
totalizando 450 horas.homem de esfor?o amostral. Registraram-se dezesseis esp?cies,
seis de lagartos (Fam?lias Mabuyidae, Tropiduridae, Gekkonidae e Phyllodactylidae), seis
de serpentes (Fam?lias Boidae e Dipsadidae) e quatro de anf?bios da Fam?lia Hylidae. O
efeito da borda da mata sobre a distribui??o das esp?cies ao longo do afloramento foi
significativo, com a maioria das esp?cies encontradas nas bordas do afloramento.
Constataram-se diferen?a significativa entre alguns pares de esp?cies com rela??o ao uso
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das brom?lias, e sobreposi??o de nicho quase total no uso de microhabitat. 62.5% das
esp?cies s?o de h?bito noturno e utilizaram essas plantas para abrigo, reprodu??o e
alimenta??o. Quanto ?s rela??es entre o lagarto Psychosaura agmosticha e as brom?lias
macambiras, foram registrados os comportamentos de termorregula??o e de forrageio nas
esta??es seca e chuvosa. Os per?odos de atividade foram concentrados entre 07 e 10 h e
entre 15 e 17 horas nas duas esta??es, demostrando um padr?o claramente bimodal. A
esp?cie usou basicamente as folhas verdes e n?o houve diferen?as significativas entre
machos e f?meas na utiliza??o das brom?lias. Associa??es positivas foram encontradas
entre a temperatura do corpo e temperaturas das brom?lias e do ar. Esta esp?cie passou
em m?dia 1.95 ? 3.8% do tempo em movimento (PTM) e se movimentou em m?dia 0.36
? 2.1 segundos por minuto (MPM), com diferen?as significativas entre as esta??es
chuvosa e seca para PTM, e tamb?m entre o tempo m?dio da parada e dura??o m?dia dos
movimentos, sendo considerada forrageadora sedent?ria. Psychosaura agmosticha, na
?rea estudada, ? bromel?cola, utilizando as macambiras principalmente para
termorregula??o e forrageio. Os resultados deste estudo destacam as brom?lias rup?colas
Encholirium spectabile como elementos chaves para a manuten??o de anf?bios e r?pteis
a ela associados, e uma clara associa??o vantajosa para a conserva??o dos grupos
envolvidos. / Bromeliads are an important microhabitat for the herpetofauna, for being widely
used as refuge from predators and their leaf architecture allows humidity maintenance
and relatively constant temperature inside, setting a favorable environment for
amphibians and reptiles, especially in areas under hydric stress. However, studies
addressing this relationship are still incipient and more concentrated in fitotelmatas
bromeliad. For non-fitotelmatas rupicolous bromeliads of the gender Encholirium, which
develops into rocky outcrops and contains species of semi-arid regions such as the
Caatinga, animal-plant relationships are almost unknown. In this context, this study aimed
to know the herpetological fauna inhabitant of macambiras bromeliads, Encholirium
spectabile, analyzing occupation and use of these bromeliads by different taxa, and the
behavioral ecology of the lizard Psychosaura agmosticha, seeking to identify factors
associated with this strict relationship in Caatinga. An extensive review of the world
literature on the subject ?lizards in bromeliads? subsidized this study from the ecological
perspective of this association. The field work was carried out at Fazenda Tanques,
municipality of Santa Maria / RN, mesoregion of Agreste Potiguar. The observations
and/or data collection in daytime and in the evening was conducted monthly during three
consecutive days, from January 2011 to August 2012, totaling 450 hour.man of sampling
effort. Sixteen species were registered: six lizards (Mabuyidae, Tropiduridae, Gekkonidae
and Phyllodactylidae Families), six snakes (Boidae and Dipsadidae Families) and four of
amphibians of Hylidae Family. The effect of the forest edge on the distribution of species
along the outcrop was significant, with most species found in outcrop edges. Significant
difference was found between some pairs of species concerning use of bromeliads, and
almost total niche overlap in the use of microhabitat. 62.5% of the species are nocturnal
and use these plants for sheltering, breeding and feeding. Regarding the relations between
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the lizard Psychosaura agmosticha and macambiras bromeliads, behaviors of
thermoregulation and foraging in the dry and wet seasons were recorded. Activity periods
were concentrated between 7 and 10 am and between 3 and 5 pm in both seasons, showing
a clear bimodal pattern. The species basically used the green leaves and there were no
significant differences between males and females in the use of bromeliads. Positive
associations were found between body temperature and temperatures of bromeliads and
air. This species spent 1.95% ? 3.8 of the time moving (PTM) and moved on average 0:36
? 2.1 seconds per minute (MPM), with significant differences between the wet and dry to
PTM, and between the average time of stop and average duration of movements, being
considered a sedentary forager. Psychosaura agmosticha, in the study area, is
bromelicolous and uses macambiras primarily for thermoregulation and foraging. The
results of this study elevate the rupicolous bromeliads Encholirium spectabile as key
elements for the maintenance of amphibians and reptiles associated with it, and a clear
advantageous association for the conservation of the groups involved.
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Brominated Skeletal Components of the Marine Demosponges, Aplysina cavernicola and Ianthella basta: Analytical and Biochemical InvestigationsKunze, Kurt, Niemann, Hendrik, Ueberlein, Susanne, Schulze, Renate, Ehrlich, Hermann, Brunner, Eike, Proksch, Peter, Pée, Karl-Heinz van 28 November 2013 (has links) (PDF)
Demosponges possess a skeleton made of a composite material with various organic constituents and/or siliceous spicules. Chitin is an integral part of the skeleton of different sponges of the order Verongida. Moreover, sponges of the order Verongida, such as Aplysina cavernicola or Ianthella basta, are well-known for the biosynthesis of brominated tyrosine derivates, characteristic bioactive natural products. It has been unknown so far whether these compounds are exclusively present in the cellular matrix or whether they may also be incorporated into the chitin-based skeletons. In the present study, we therefore examined the skeletons of A. cavernicola and I. basta with respect to the presence of bromotyrosine metabolites. The chitin-based-skeletons isolated from these sponges indeed contain significant amounts of brominated compounds, which are not easily extractable from the skeletons by common solvents, such as MeOH, as shown by HPLC analyses in combination with NMR and IR spectroscopic measurements. Quantitative potentiometric analyses confirm that the skeleton-associated bromine mainly withstands the MeOH-based extraction. This observation suggests that the respective, but yet unidentified, brominated compounds are strongly bound to the sponge skeletons, possibly by covalent bonding. Moreover, gene fragments of halogenases suggested to be responsible for the incorporation of bromine into organic molecules could be amplified from DNA isolated from sponge samples enriched for sponge-associated bacteria.
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