1,721,057 research outputs found
Workplace Wellness, Mental Health Literacy, and Intention of using E-Mental Health among Digital Workers during COVID-19 Pandemic
No full textThis dataset contains the questions of the instrument that was used for this study
Exploring acceptance of the eHealth model for mental wellness among digital workers
No full texteHealth makes use of information and communication technologies (ICT) to improve health. In the digital age, the use of eHealth applications and other health-related applications has gained popularity, particularly during the COVID-19 pandemic. As a result of the pandemic, many uncertainties have arisen, causing stress and affecting the mental health of many skilled workers in the digital industry, particularly in the ICT, computing, and creative media industries. eHealth applications have the potential to benefit people's health. As a prerequisite for effective implementation of eHealth for mental wellness (EHMW), this paper examines the acceptance of EHMW among digital workers in Malaysia
Functionalization of cellular membrane by cholesterol-dendrimer conjugates
No full textMaster'sMASTER OF SCIENC
IF(1): setting the pace of the F(1)F(o)-ATP synthase
No full textWhen mitochondrial function is compromised and the mitochondrial membrane potential (Deltapsi(m)) falls below a threshold, the F(1)F(o)-ATP synthase can reverse, hydrolysing ATP to pump protons out of the mitochondrial matrix. Although this activity can deplete ATP and precipitate cell death, it is limited by the mitochondrial protein IF(1), an endogenous F(1)F(o)-ATPase inhibitor. IF(1), therefore, preserves ATP at the expense of Deltapsi(m). Despite a wealth of detailed knowledge on the biochemistry of the interaction of IF(1) and the F(1)F(o)-ATPase, little is known about its physiological activity. Emerging research suggests that IF(1) has a wider ranging impact on mitochondrial structure and function than previously thought
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Bisguanidiums catalyzed enantioselective oxidation of sulfides to sulfoxides
No full textChiral sulfoxides are the functional groups in many drugs. In synthesis, the most direct and economic way is oxidized by oxidants. Contemporarily, the most meritorious and practical oxidation method was improved according to Sharpless-Kagan’s system. However, it has been serving us for more than three decades, and it is no longer a sufficient method to satisfy the environmental problem. For instance, in most of cases, an environmental benign oxidant hydrogen peroxide is less-favoured than UHP (urea hydrogen peroxide) and CHP (cumyl hydroperoxide) in homogenous system. Additionally, metal complex coordinated with organic ligands is hard to be removed from organic phase, which causes a lot of trouble in processing procedure. Thus, organocatalyzed heterogeneous oxidation realized by hydrogen peroxide is put forward by using our phase-transfer catalyst. Another associated catalytic oxygen transfer reagent is tungstate oxide anion. When developing this new methodology for oxidation of chiral sulfoxides, both chemoselectivity and enantioselectivity should be considered. Our novel catalyst solves the former problem by oxygen transfer anion, and the later problem is solved by our chiral cation. This process would be leaded by electron force and π-π interaction between substrates and catalyst as proposed.Master of Scienc
Asymmetric nucleophilic substitutions to construct all-carbon quaternary stereocenters under PTC conditions
No full textNucleophilicity and nucleophilic substitution is one of the most important concepts and processes in organic chemistry. Traditionally, the term nucleophilic substitution in organic chemistry implies substitution exactly at the carbon atom, but there is a rather wide class of reactions in which the nucleophile attacks a halogen atom but not the carbon atom, such reactions, then are named halophilic or halogenophilic reactions and proceeded by SNX route.
Herein we describe a novel asymmetric nucleophilic substitution to construct all-carbon quaternary stereocenters under PTC conditions. In this reaction, the C-Br bond is cleaved to generate a newly C-C bond with high enantioselectivity. Different kinds of tertiary bromides with electron withdrawing groups are proved to be excellent electrophiles for malonates under a base condition. We envisioned that the breakthrough of the C-halogen bond is proceed by a SNX route and our guanidiniums PTC induce the formation of the all carbon quaternary canter. This concept provide a new direction for the development of nucleophilic substitutions.Doctor of Philosoph
Asymmetric allylic alkynylation catalyzed by guanidine copper(I) complex
No full textThe main project during my Ph.D. period was devoted to developing the asymmetric allylic alkynylation of racemic chiral substrates in the presence of Cu(I) and chiral guanidinium catalysts. Previously developed guanidine-derived chiral organocatalysts in Prof Tan Choon Hong’s lab were applied into asymmetric transition-metal catalyzed coupling reaction for the first time, showing great efficiency in the stereoconvergent transformation of racemic cyclic allylic bromides. My Ph.D. thesis is divided into three chapters here to better narrate the exploration of asymmetric allylic alkynylation of racemic chiral substrates catalyzed by (guanidine)copper(I) complex.
Chapter 1 introduces the unique properties of guanidine-type molecules, including its neutral form (guanidine), cationic form (guanidinium) and anionic form (guanidinate). Through reviewing their coordination chemistry and catalytic applications in metal-catalyzed reactions, the potentiality of our cyclic guanidines as a ligand or guanidinium as a cation directing metallate is highlighted. Inspired by a Cu-catalyzed asymmetric allylic alkynylation under phase-transfer condition reported by Alper, two chirality induction modes are proposed for an unprecedented Cu-catalyzed stereoconvergent transformation. Chapter 2 demonstrates the current development and challenges of Cu-catalyzed AAAs as well as the detailed condition optimization and scope of asymmetric allylic alkynylation of racemic chiral substrates with copper(I)/guanidinium system. Various reaction conditions, including solvents, catalysts, bases, metal sources and leaving groups were evaluated with orthogonal experiments. An array of unsubstituted or substituted cyclic allylic bromides were transformed to corresponding 1,4-enynes in good yields and high enantioselectivity. Further enantio-retentive transformations of enantioenriched1,4-enynes were also discussed. Chapter 3 describes the efforts to figure out the most reasonable mechanism of this reaction. Firstly, the mechanistic principles of Cu-catalyzed AAAs and different types of mechanism-dependent stereoconvergent transformations were discussed. Analytical strategies including X-ray, CSI-MS, and NMR were used to identify the catalytic resting species thus the chirality induction mode could be preliminarily determined. Further experimental and computational studies of this reaction supported that this reaction belongs to a Type II Dynamic Kinetic Asymmetric Transformation.Doctor of Philosophy (SPMS
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