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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.
161

Revisão taxonômica das aranhas neotropicais do gênero Ariadna Audouin, 1826 (Araneae, Segestriidae) / Taxonomic revision of neotropical Ariadna Audouin, 1826 (Araneae, Segestriidae)

Giroti, André Marsola 30 October 2013 (has links)
O gênero Ariadna Audouin, 1826 compreende atualmente 99 das 119 espécies descritas taxonomicamente para Segestriidae. Distribui-se em todos os continentes (exceto a Antártida), sendo mais abundante em regiões tropicais e subtropicais. No presente estudo é apresentada uma revisão taxonômica de Ariadna na Região Neotropical, juntamente com um trabalho de maior detalhamento e descrição da morfologia corporal e das genitálias masculina e feminina das espécies, diagnosticando-as de forma mais clara. Após análise de aproximadamente 2200 exemplares tipos e não-tipos advindos de 24 coleções nacionais e internacionais, foram encontradas 30 espécies taxonomicamente válidas para a Região Neotropical, sendo 22 anteriormente descritas e 8 espécies novas: Ariadna sp. n. 1, Ariadna sp. n. 3, Ariadna sp. n. 4, Ariadna sp. n. 6, Ariadna sp. n. 7 e Ariadna sp. n. 8 descritas para o Brasil; Ariadna sp. n. 2 descrita para a América Central; e Ariadna sp. n. 5 descrita para o Chile. Sete espécies foram sinonimizadas: A. pragmática com A. bicolor, A. gracilis e A. conspersa com A. obscura, A. murphyi com A. tarsalis, A. pusilla com A. maxima, A. dúbia com A. boliviana, e A. spinifera com A. mollis. Duas espécies estão sob proposta de nomina dubia: A. solitária e A. tubicola. O alótipo de A. crassipalpa descrito por Camargo (1950) e o parátipo de A. levii descrito por Grismado (2008), foram identificados como A. mollis e A. máxima, respectivamente, sendo considerados identificações errôneas. O macho de A. cephalotes e a fêmea de A. calilegua estão sendo descritos pela primeira vez. Vinte e cinco espécies foram alocadas em seis grupos: grupo bicolor, grupo arthuri, grupo mollis, grupo boliviana, grupo araucana e grupo sp. n. 6, com base em caracteres morfológicos compartilhados entre as espécies de cada grupo. Cinco espécies não foram alocadas devido a não compatibilidade destas com nenhum dos grupos supracitados: A. maxima, A. cephalotes, A. tovarensis, A. fidicina e A. abrilae. A hipótese de agrupamento apresentada neste estudo, reforçou o posicionamento de algumas espécies anteriormente feito por Beatty (1970) / The genus Ariadna Audouin, 1826 currently comprises 99 of the 119 described species of Segestriidae. Its distribution comprises all continents (except Antarctica), but is found most on the tropical and subtropical regions. In this study, a taxonomic revision of Ariadna in the Neotropical region is presented, together with detailed descriptions of the body morphology, and male and female genitalia. After the examination of nearly 2200 type and non-type specimens from 24 national and international collections, we detected 30 species taxonomically valid for the Neotropical region, 22 previously described and eight new: Ariadna sp. n. 1, Ariadna sp. n. 3, Ariadna sp. n. 4, Ariadna sp. n. 6, Ariadna sp. n. 7 e Ariadna sp. n. 8 from Brazil; Ariadna sp. n. 2 from Central America e Ariadna sp. n. 5 from Chile. The following taxa are newly synonymized: A. pragmatic with A. bicolor, A. gracilis and A. conspersa with A. obscura, A. murphyi with A. tarsalis, A. pusilla with A. maxima, A. dubia with A. boliviana, e A. spinifera with A. mollis. Two species were proposed as nomina dubia: A. solitaria and A. tubicola. The allotype of A. crassipalpa described by Camargo (1950) and the paratype of A. levii described by Grismado (2008) were identified as A. mollis and A. maxima, respectively. The male of A. cephalotes and the female of A. calilegua are described for the first time. Twenty five species were placed in six groups: bicolor group, arthuri group, mollis group, boliviana group, araucana group and sp. n. 6 group, based in putative synapomorphies between the species. Five species were not placed in any of the groups due to the incompatibility between the morphological characters presented by them and the grouped species: A. maxima, A. cephalotes, A. tovarensis, A. fidicina and A. abrilae. The grouping hypothesis presented in this study, reinforced the position of some of the species grouped by Beatty (1970)
162

Personality Factors Associated with Negative Affect: Application of the "Big Five" Taxonomy to Depression and Anxiety

Anderson, Kent W. 01 May 1994 (has links)
The purpose of this study was to examine the patterns and discriminant utility of the five-factor model of personality ( "Big Five," consisting of neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness factors) with depressed and anxious outpatients. One hundred two outpatients seeking services at a community mental health center in a small western community participated in the study. Subjects were 41 clients with a depressive disorder, 31 with an anxiety disorder, and 30 in a mixed clinical control group. Subjects completed the Neuroticism-Extraversion-Openness to Experience Five-Factor Inventory (NEO-FFI). Results indicate that both depressed and anxious clients score in the "very high" range on neuroticism and "low" on extraversion. However , neither of these two factors is useful in discriminating between depression and anxiety since their mean scores are essentially equivalent . Conscientiousness is the crucial variable that discriminates between depressed and anxious clients. The mean score for the anxiety group is in the "very low" range, significantly lower than the depressed group whose mean is in the "low-average" range. Openness to experience contributes mildly to discriminant utility, with the mean score of the depressed group in the "high-average" range and the mean score of the anxiety group in the "average" range. The agreeableness variable contributes minimally to the discriminant function.
163

Common Strategies for Regulating Emotions across the Hierarchical Taxonomy of Psychopathology (HiTOP) Model

Bennett, Charles B 08 1900 (has links)
The hierarchical taxonomy of psychopathology (HiTOP) is a novel classification system that adopts both a dimensional and hierarchical approach to psychopathology to address shortcomings. However, the HiTOP framework is descriptive in nature and requires additional research to consider potential mechanisms for the onset and maintenance of psychopathology, such as cognitive-behavioral emotion regulation strategies. To redress this gap, a sample of 341 adults who endorsed ongoing mental health concerns completed self-report measures of emotion regulation strategies and psychopathology. The data revealed a three-spectra HiTOP model consisting of internalizing, thought disorder, and antagonistic externalizing. Results found that psychopathology was most strongly associated with avoidance, catastrophizing, expressive suppression, and self-blame. In contrast, adaptive strategies were generally unrelated to the HiTOP spectra. This pattern was strongest for internalizing, distress, and detachment. Fewer, yet noteworthy unique relationships between the strategies and specific spectra/subfactors were also found. These findings suggest that psychopathology may be best conceptualized as an overutilization of maladaptive emotion regulation strategies. Furthermore, the results indicate there is added benefit to considering these strategies within a hierarchical approach to psychopathology. These associations alert clinicians to potential treatment targets and contribute to an ongoing literature that seeks to identify underlying mechanisms of the structure of psychopathology.
164

Making sense of Computer Supported Cooperative Work: A taxonomy of terminology

Ward, Sylvia Ann, s.ward@cqu.edu.au January 2007 (has links)
There are four contributions of this research: 1) confirmation of inconsistent use of terminology in the Computer Supported Cooperative Work (CSCW) research field; 2) the development of a hierarchical terminology technique that extends the idea of cognitive mapping into a hierarchy of concepts and dictionary of related definitions; 3) a taxonomy of terminology showing the boundary of the CSCW research field; and 4) a dictionary of definitions relating to the terminology in the taxonomy. The investigation of prior research in this field found that there was a proliferation of terms all relating to support of groups, and there was a proliferation of software and systems that support groups. However, the terminology and definitions used by researchers were found to be inconsistent, with some terms being defined differently, but then used interchangeably. Inconsistency makes it difficult to determine what technology is being used in the research and where a research study fits into the research field. Knowledge of any research field is mainly gained through reading published research documents. This research analysed published documents in Computer Supported Cooperative Work (CSCW) to determine the scope, structure and meaning of the terminology used in this research field. The research resulted in a hierarchy of terminology and a dictionary of definitions. Future research will determine the value of these structures for new researchers, experienced researchers, and practitioners. During the investigation of prior research no technique was identified to undertake such a study. A hierarchical terminology technique (HTT), which is a form of content analysis process, was developed to structure a hierarchy of concepts to expose the relationships between terms. This technique includes terminology identification, analysis and presentation to show the scope of a research field and to present terminology and definitions to improve consistency. This technique can be used in other fields of study.
165

Development and Construct Validation of a Measure of Soft Skills Performance

Kantrowitz, Tracy Michelle 10 April 2005 (has links)
Despite the growing interest in studying the dimensions and prediction of task and contextual performance, little empirical attention has been given to studying the nature of soft skills performance. Soft skills (i.e., intra- and inter-personal work skills that facilitate the application of technical skills and knowledge), such as interpersonal skills (e.g., developing rapport) and communication skills (e.g., adjusting your message to the target audience) are highly sought by organizations (Zedeck and Goldstein, 2000). However, little is known about the underlying dimensions of soft skills performance, or about the individual differences variables that predict performance in this domain. In the current set of studies I examined the dimensionality of soft skills performance, developed measures to assess soft skills performance from self and supervisor perspectives, and validated the measures of performance in a nomological network of non-ability individual differences and existing performance measures. Study 1 involved asking subject matter experts to provide a master list and critical incidents of soft skills. Data from Study 1 served as the stimuli in Study 2 for sorting and reduction of skills into dimensions of soft skills performance. A construct and criterion validation approach was taken in Study 3 to measure soft skills performance in relation to individual differences variables in a nomological network. Results showed that the taxonomy of soft skills performance was composed of seven clusters, but that the measure of soft skills performance was unidimensional. Personality and motivational variables significantly predicted soft skills performance through their influence on proximal motivational processes.
166

Journeys within the Leucophoropterini: Revision of the Tribe, Genera and Species, and Description of New Genera and Species from Australia and the Indo-Pacific

Menard, Katrina Louise 2011 May 1900 (has links)
The tribe Leucophoropterini (Miridae: Phylinae) is a diverse assemblage of primarily Indo-Pacific and Australian bugs which are united by simple, small genitalia and a trend towards ant-mimetic body forms. Previous to this work, the relationship of the Leucophoropterini to the other tribes of Phylinae, as well as the generic relationships within the lineage, was unresolved. Further, the characters initially proposed to unite the tribe are brought into question with the addition of several recently discovered taxa from Australia. The Leucophoropterini is first re-evaluated within a phylogenetic analysis of the subfamily Phylinae, using a combined molecular and morphological dataset to test the monophyly of the lineage, re-test the character synapomorphies supporting it, and to determine the closest relatives to the tribe. The molecular dataset includes 4 genes (COII, 16S, 28S, and 18S), and 123 morphological characters for 104 taxa, which is analyzed in a parsimony analysis using Tree analysis using New Technology [TNT], a model-based analysis in RAxML, and a Bayesian analysis in Mr. Bayes. All three methods resulted in phylogenetic trees with nearly identical generic and tribal groupings, and a lineage containing Pseudophylus Yasunaga, Decomia Poppius and Tuxedo Schuh being sister-group to the Leucophoropterini. With the closest relatives to the Leucophoropterini determined for outgroup selection, a generic revision of the tribe including both Australian and Indo-Pacific taxa is accomplished using 137 morphological characters and is analyzed in an un-weighted and implied weighted parsimony analysis using TNT for 86 leucophoropterine taxa. The Indo-Pacific taxa of Leucophoropterini are found to be related to the Australian Leucophoropterini, and at least two genera within the tribe (Sejanus Distant, Leucophoroptera Poppius) were found to be paraphyletic. Lastly, taxa are revised within the context of the generic-level phylogenetic analysis, with new genera and species from Australia and the Indo-Pacific being described.
167

A Taxonomic Study on Lentibulariaceae of Taiwan

Chao, Yi-Shan 28 January 2004 (has links)
Utricularia is the only genus in Lentibulariaceae of Taiwan. The morphology of Utricularia is highly diverse due to the habitats variation, which results in the difficulty to identify the species of this genus. This study emphasizes the morphology of Utricularia, and combines with the information of field observation and the cultivation, to ensure the influence of environmental change on external morphology, especially the characters of stolons, rhizoids, leaves, flowers, fruits, pollens, seeds, and traps. Further, the taxonomic value of trap glands between species is discussed. There are seven species recognized in Lentibulariaceae of Taiwan; namely, U. aurea Lour., U. australis R. Br., U. bifida L., U. caerulea L., U. gibba L., U. striatula Sm., and U. uliginosa Vahl. In addition, U. minor L. and U. inflata Walter are treated as doubtful species.
168

Taxonomy, distribution and reproduction of deep-sea eels in Taiwan waters and the phylogeny of Anguilliformes and Congroidei (Elopomorpha: Teleostei)

Chen, Yu-Yun 16 December 2002 (has links)
Abstract There are 43 species of deep-sea eels of 8 families, which including 1 species of Chlopsidae, 2 species of Muraenidae, 3 species of Ophichthide, 14 species of Congridae, 2 species of Muraenesocidae, 2 species of Nemichthyidae, 2 species of Nettastomidae, and 15 species of Synaphobranchidae, which its depth from 150 to 1200 meters and distribution from NE coast to the coast of Taitong and SW coast in Taiwan waters. Meanwhile, there are 3 new species (i.e., Dysomma longirostrum, Ophichthus aphotistos, Synaphobranchus sinensis) and 11 new records (i.e., Chilorhinchus platyrhynchus, Ophisurus macrorhynchus, Rhechias retrotincta, Macroceohenchelys brachialis, M. soela, Japonoconger sivicolus, nettastoma solitarium, Meadia abyssale, Dysommina rugosa, Ilyophis brunneus, Synaphobranchus kaupi) are described. The study in this part also recognize vertebral formulae is useful of elucidating the difference among the species. Morphology of swimbladder, stomatch, gonads of the deep-sea eels and the melanin layer of diaphragm are able to be as a distinctive character to find out the relationship among the species and the families. Most eels¡¦ reproductive season concentrate on September to November, whatever, the synaphobranchids have two reproductive seasons, which are on May and September to October. And it should become important to make further research on the above phenomenon. True eels (anguilliforms) form a monophyletic taxon from 16 apomorphic characters, e.g., Well-developed olfactory bulbs, lateral-protruded telencephalon, large-sized tectum, a distinct gap between telencephalon and tectum, reduced neural arch, hamel arch, and uroneural, triangled urostyle, epural absent, convergent hypural, fused hypural 1-2 and hypural 3-4-5, gap between hypural 1-2 and parhypural, and a gap between hypural 1-2 and hypural 3-4-5. The present study also find (1) Muraenoidei and angulloidei are a sister ¡Vgroup by sharing a slit between telencephalon and tectum, smaller olfactory bulb and lobe, and slit on area posttrema; (2)Congroidei is a monophyletic group by sharing an oval tectum, large cerebellum, and ungrooved area postrema, fusion of hypural 3, 4, and 5; (3) Congroidea and Synaphobranchoidea share a fusion of parhypural with hypural 1 and a concave present between uroneural and hypural, which should be treated as a sister group; (4) most eels of Congridae share a FS-caudal-fin and should be treated as a clade; (5) Most eels of Ophichthidae share a reduced and degraded caudal-fin, which should be monoplyletic; (6) Synaphobranchinae¡BSimenchelyinae and Ilyophinae, uniquely sharing well¡Vdeveloped olfactory bulb, small telencephalon, lateral protrusion of telencephalon well developed, and cerebellum folded posteriorly, a CLC- caudal-fin and elevated hypural 3-4-5, and fusion of hypural 4 and 5, are belong to a monophyletic group; (7) a gap between parhypural and hypural 1 indicate Simenchelyinae and Ilyophinae should be treated as a sister group; (8) Eurypharynx, Cyema, and Monognathus sharing a reduced caudal fin and brain, which need further research to elucidate their relationship; (9) Dark-red saccus vasculosus appears to recommend a close relationship between Gavialiceps taeniola and duckbill eels. (10) A disc-like hypophysis suggests the eels, Albula, Pterothrissus, Notacanthus, Megalops, and Elops are closely related groups; (11) Albula, Pterothrissus, Megalops, and Elops share a distinct morphological type of tectum and cerebellum and they should be treated as closely related groups; (12) The brains¡¦ gross morphology of Albula, Pterothrissus, Megalops, and Elops are well developed, a correlation distinctly similar to that of the Clupea which need further study on the relationship among the taxa mentioned above and the Clupeiformes.
169

Synopsis of the morphology and taxonomy of Carex section Glaucescentes in North America

McLaughlin, Diane Coston 15 November 2004 (has links)
Field studies were used to characterize habitat and evaluate morphological characters of Carex glaucescens, C. joorii and C. verrucosa. Morphometric analysis of herbarium specimens along with field studies, Environmental Scanning Electron Microscopy (ESEM), pollen viability and phenology show C. glaucescens, C. joorii and C. verrucosa to be taxonomically distinguishable at the species level. The taxonomy of Carex section Glaucescentes is presented in an artificial dichotomous key to the taxa and in species descriptions.
170

A Study of Primary 5 and 6 Students¡¦ Capabilities on Leaf Form Cognition and Related Taxonomy

Sun, Tsui-hui 22 January 2010 (has links)
The purpose of this study is to provide effective strategies and suggestions of models for self-study tools suitable to fifth and sixth graders, by leading fifth and sixth grade students to establish hierarchal polycalve and dichotomous plant keys through observation, description, comparison, and synthesis in the activity-based courses of observation and classification of plant leaves, and by analyzing children¡¦s level of form cognition and capability of classification via children¡¦s observation records, the taxonomy model, and the contents of keys. In addition, this study aimed to realize students¡¦ learning difficulties regarding plants through their work, comments, interviews and the quantitative data. Also, by means of the reforms to relevant teaching methods and teaching material, this study showed how students could have a better learning experience with plants. Based on the quantitative and qualitative data, the major findings of this study are summarized as follows: 1. Observation capability: The tactile sense was the important medium by which primary school students explore the world, with leaf texture in the highest observational record. Visually, students had better observation capabilities for characteristics of larger-scale forms. 2. Classification model: The standards that students most commonly used were ¡§color,¡¨ ¡§vein,¡¨ ¡§margin,¡¨ and ¡§shape.¡¨ The results of classification were more consistent with the last three standards, and the results of classification in groups were especially similar when proper morphological terms were used to express classified items. It was thus clear that morphological terminology can help students to classify plants. 3. Plant key: When devising the plant key suited to primary school students, it was better to use the polyclave method in one searching stage to show different characteristics in the same region, and to use the dichotomous method to show similar characteristics that are difficult to distinguish. When expressing options using clip art and proper terms simultaneously, students exhibited the best comprehension. 4. Studying attitude According to the quantitative data, activity-based courses only raised students¡¦ learning interest a little. However, interviews and sharing of study experiences revealed that learning by doing can improve their observational capabilities and learning memories. In addition, students would be more concerned for the relationship between human beings and the environment.

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