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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.
151

Using Developmental Cascade Models to Explain Directionality Between Rejection Sensitivity and Maladaptive Traits Across Adolescence

Beeson, Christina Marie Linda 08 May 2020 (has links)
The fundamental need to belong is considered one of the most basic human requirements, and universally motivates human behaviour. When this need to belong is not met, it increases the risk of mental health problems like depression, which was of interest in this dissertation. Due to the psychological consequences of not being accepted by others, humans are very attuned to perceived threats to belonging and have developed types of defense mechanisms to protect themselves against social exclusion. One such defense mechanism is rejection sensitivity, and the role of rejection sensitivity as it relates to depression was the underlying theme of this dissertation. Along with rejection sensitivity, there exist external and internal factors that serve as threats to belonging, and which are associated with depression. Two of these factors, rejection (an interpersonal factor) and perfectionism (an intrapersonal factor) were examined in relation to depression. Study 1 focused on peer rejection and the developmental pathways involved in its relation to rejection sensitivity, depression, and aggression in adolescence. Results showed that rejection and rejection sensitivity were preceded by either depression or aggression across adolescence, and although depression initiated the cascade leading to rejection sensitivity, there was a bidirectional relation across late adolescence as rejection sensitivity also predicted future depression. Study 2 focused on two types of perfectionism (i.e., self-oriented and socially prescribed), including the developmental pathways associated with their relation to rejection sensitivity and depression in adolescence. Socially prescribed perfectionism was directly related to future depression and rejection sensitivity mediated the relation between self-oriented perfectionism and depression. Depression initiated the cascade leading to rejection sensitivity and supported a bidirectional relation across late adolescence. Study 3 also focused on perfectionism, but cross-sectionally in young adults, and examined three types of perfectionism (i.e., self-oriented, socially prescribed, and other-oriented). Rejection sensitivity and socially prescribed perfectionism were positively related to depression, and other-oriented perfectionism was negatively related to depression; however, self-oriented perfectionism did not contribute significantly to depression. Contrary to what was predicted, rejection sensitivity was not a significant moderator in the relation between perfectionism and depression. Overall, rejection sensitivity, a defense mechanism against threats to the need to belong, played a significant role in the development and maintenance of depression in the absence of actual rejection, as well as in conjunction with specific types of perfectionism.
152

Synthesis of terpenoids using a tandem cationic cascade cyclization-electrophilic aromatic substitution reaction

Shah, Parin Ajay 01 January 2018 (has links)
The terpene and terpenoid family of compounds is considered to be the largest group of natural products. These compounds not only display great diversity in their structural features but are also known to have a multitude of biological activities including but not limited to anti-bacterial, anti-cancer, anti-inflammatory, and anti-HIV properties. Remarkably, all the terpenoids formed in nature come from two molecules viz. isopentenyl pyrophosphate and its isomer, dimethylallyl pyrophosphate both consisting of just five carbons but assembled in many ways. Nature utilizes highly efficient, enzyme-mediated cascade reactions to transform simple linear molecules to more complex cyclic scaffolds. Cascade or domino reactions are organic chemistry’s most powerful tools that, if executed correctly, mimic the extreme complexity of reactions occurring in nature. Our group has successfully utilized cationic cascade cyclization reactions, to prepare a large library of natural products along with their analogues. It was during the synthesis of one such natural product that it was discovered that a methoxymethyl (MOM) “protecting group” had been transferred within the same molecule. The optimization of this process not only allowed the synthesis of the desired tricyclic framework but also resulted in the liberated MOM group doing an EAS reaction which gave a new C-C bond. This transferred MOM group was further elaborated to different functional groups. Use of the tandem reaction sequence in an attempt to prepare radulanin E has been described. Total syntheses of two chalcone-based analogous meroterpenoids have been successfully completed using the aforementioned sequence. An advanced intermediate for an entire new class of acridine-based schweinfurthins has been elaborated. The results will be discussed in detail.
153

Cascade

Dougherty, Kevin Alexander 24 May 2022 (has links)
No description available.
154

Middle and upper Eocene biostratigraphy (Foraminifera) of the Cascade Head area, Lincoln and Tillamook Counties, Oregon

Callender, Arden D., Jr. 27 January 1977 (has links)
An almost complete sequence of middle and upper marine strata, informally designated in this study as the "Strata of Cascade Head", has yielded 334 species and varieties of fossil Foraminifera. The Foraminifera were collected from 38 localities in four stratigraphic sections measured along the Salmon River, Neskowin Creek, Cascade Head Road, and near the town of Three Rocks in the central Oregon Coast Range.
155

Geology of the Breitenbush Hot Springs area, Cascade Range, Oregon

Clayton, Clifford Michael 01 January 1976 (has links)
The Breitenbush Hot Springs area lies on the boundary of folded middle to late Tertiary Western Cascade rocks and younger High Cascade rocks. Within the mapped area the Western Cascade rocks are represented by four formations. The Detroit Beds, a sequence of interstratified tuffaceous sandstone, mudflow breccia, and tuff, is overlain unconformably by the Breitenbush Tuff. The Breitenbush Tuff consists of three units of welded pumice-rich crystal-vitric ash-flow tuffs interbedded with tuffaceous sedimentary rocks. The Outerson Formation unconformably overlies the Breitenbush Tuff and consists primarily of basaltic lava and breccia. The Outerson Formation includes three localized members: a basal, glassy, aphanitic basalt, the Lake Leone Sediments, and the Outerson Tuff. The Outerson Formation is cut by a number of feeder dikes and plugs and is unconformably overlain by the Cheat Creek Sediments, composed of volcanic sedimentary rocks and a distinctive basaltic tuff. The Western Cascade formations total more than 1660 m {5500 ft) of strata and range from Oligocene to Pliocene in age. The High Cascade rocks are represented by two formations: the Triangulation Peak Volcanics of basalt and andesite lava and breccia, lying unconformably atop the Cheat Creek Sediments; and unconformably beneath the Collowash Volcanics, a series of thin basaltic lava flows and breccias. The Western and High Cascade rocks are covered extensively by surficial deposits, primarily glacial drift. The High Cascade formations are at least 840 m (2800 ft) thick, ranging in age from Pliocene to Pliestocene. The Western Cascade rocks have been folded and faulted in the Breitenbush Hot Springs area, and form the eastern limb of the north-trending Breitenbush Anticline. The folded rocks and the erosional unconformities between the rock units probably represent two local episodes of orogeny: one in early to middle Miocene and another in late Pliocene to Pleistocene time. The Outerson Formation represents a depositional sequence between the periods of uplift and deformation. Faulting accompanied the orogenic sequences. The primary volcanic landforms in the area have been destroyed by erosion but skeletal remains of High Cascade volcanoes are recognized. Stream erosion and glaciation are responsible for the present landforms. Breitenbush Hot Springs occurs, in part, along basaltic dikes which channel the water through impermeable Breitenbush Tuff. The dikes are believed to be associated with the Outerson basalts. The Hot Springs discharge upwards at 3400 l/min. (900 gpm) of water at temperatures up to 92°C (198°F).
156

Synthesis of Heterocyclic Scaffolds through Transition-Metal-CatalyzedCascade Reactions of Alkynes / 遷移金属触媒によるアルキンのカスケード反応を用いた複素環骨格構築法の開発

Tokimizu, Yusuke 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第18928号 / 薬科博第42号 / 新制||薬||5(附属図書館) / 31879 / 京都大学大学院薬学研究科医薬創成情報科学専攻 / (主査)教授 大野 浩章, 教授 高須 清誠, 教授 竹本 佳司 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
157

Development of Novel Methods for Synthesis of Fused Indole-Type Compounds / 縮環インドール系化合物の新規合成法の開発研究

Iwata, Akira 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第21051号 / 薬科博第94号 / 新制||薬科||10(附属図書館) / 京都大学大学院薬学研究科医薬創成情報科学専攻 / (主査)教授 大野 浩章, 教授 竹本 佳司, 教授 高須 清誠 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
158

Flow losses in supersonic compressor cascades

Bloch, Gregory S. 06 June 2008 (has links)
Loss models used in compression system performance prediction codes are often developed from the study of two-dimensional cascades. The physical mechanisms that affect the flow in supersonic compressor cascades have been reviewed, including the changes in shock geometry that will occur with back pressure for both started and unstarted operation. Compressible fluid mechanics has been applied to the known shock geometry to obtain a physics-based engineering shock loss model that is applicable over the entire supersonic operating range of the cascade. Predictions from the present method have been compared to measurements and Navier-Stokes analyses of the L030-4 and L030-6 cascades, and very good agreement was demonstrated for unstarted operation. Son1e of the started comparisons exhibited good agreement, while others did not. A clear improvement has been demonstrated over previously published shock loss models, both in the accuracy of the predictions and in the range of applicability. The dramatic increase in overall loss with increasing inlet flow angle is shown to be primarily the result of increased shock loss, and much of this increase is caused by the detached bow shock. For a given Mach number, the viscous profile loss is nearly constant over the entire unstarted operating range of the cascade, unless a shock-induced boundary layer separation occurs near stall. Shock loss is much more sensitive to inlet Mach number than is viscous profile loss. The present shock loss model has been used as the basis of an overall loss prediction method by adding a constant value, representative of the viscous profile loss, to the predicted shock loss characteristics. The overall loss characteristics obtained in this manner showed good agreement with the experimental values over the most useful operating range of the cascade. / Ph. D.
159

The Design and Construction of a Single Stage Cascade Analog to Digital Converter

Langley, Roger 05 1900 (has links)
<p> The thesis is concerned with the design, construction and evaluation of an analog to digital converter based on the "cascade" principle. However, this converter requires only one stage, instead of the usual one stage per bit required by conventional cascade converters. This reduction in the number of stages is achieved by storage in analog form, and by feeding the output of the stage back to its input via a switching network. An 8 bit converter that operates up to a clock frequency of 700KHz was built. The converter is shown to have promising possibilities as a low cost general purpose analog to digital converter. </p> / Thesis / Master of Engineering (MEngr)
160

Degradable Vinyl Copolymers via Photocontrolled Radical Ring-Opening Cascade Copolymerization:

Wang, Wenqi January 2023 (has links)
Thesis advisor: Jia Niu / This dissertation discusses two main projects focusing on synthesizing degradable vinyl copolymers. The first project describes the development of a general approach to synthesizing degradable vinyl random copolymers through photocontrolled radical ring-opening cascade copolymerization (rROCCP). The rROCCP of a macrocyclic allylic sulfone with acrylates or acrylamides mediated by visible light at ambient temperature achieved near-unity comonomer reactivity ratios over the entire range of feed compositions. Such a powerful approach provides degradable vinyl random copolymers with comparable material properties to their non-degradable counterparts. Experimental and computational evidence also revealed an unusual reversible inhibition of chain propagation by in situ generated sulfur dioxide (SO2), which was successfully overcome by reducing the solubility of SO2 during polymerization. The second project depicts a general method for organocatalyzed photocontrolled radical copolymerization of a macrocyclic allylic sulfone and various types of vinyl monomers, including acrylates, acrylamides, styrene, and methacrylate. Catalyzed by Eosin Y under visible light irradiation, copolymerization of the macrocyclic allylic sulfone and acrylic monomers displayed near unity comonomer reactivity ratios by fitting the copolymer composition to the Beckingham-Sanoya-Lynd integrated model. The macrocyclic allylic sulfone was also successfully copolymerized with styrene or methyl methacrylate to generate degradable polystyrene and poly(methyl methacrylate). These degradable vinyl copolymers exhibited tunable thermal properties correlated with the incorporation of degradable main-chain diester motif. / Thesis (PhD) — Boston College, 2023. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

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