Search results for "Lee"
showing 10 items of 1847 documents
Extending the Series: Synthesis and Characterization of a Dicationic N-Heterocyclic Selenium Carbene Analogue
2006
The room-temperature reaction between the Dipp2DAB ligand, SnCl2, and SeCl4 results in the quantitative formation of a dicationic N-heterocyclic “carbenoid”. This represents the first example of a chalcogenium dication that mimics the ubiquitous Arduengo-type carbenes; however, the electronic structure is significantly different. peerReviewed
77Se NMR Spectroscopic, DFT MO, and VBT Investigations of the Reversible Dissociation of Solid (Se6I2)[AsF6]2•2SO2 in Liquid SO2 to Solutions Contain…
2009
The composition of a complex equilibrium mixture formed upon dissolution of (Se6I2)[AsF6]2·2SO2 in SO2(l) was studied by 77Se NMR spectroscopy at −70 °C with both natural-abundance and enriched 77Se-isotope samples (enrichment 92%). Both the natural-abundance and enriched NMR spectra showed the presence of previously known cations 1,4-Se6I22+, SeI3+, 1,1,4,4-Se4I42+, Se102+, Se82+, and Se42+. The structure and bonding in 1,4-Se6I22+ and 1,1,4,4-Se4I42+ were explored using DFT calculations. It was shown that the observed Se−Se bond alternation and presence of thermodynamically stable 4pπ−4pπ Se−Se and 4pπ−5pπ Se−I bonds arise from positive charge delocalization from the formally positively c…
Experimental and Theoretical Investigations of Structural Trends for Selenium(IV) Imides and Oxides: X-ray Structure of Se3(NAd)2
2004
The thermal decomposition of Se(NAd)2 (Ad = 1-adamantyl) in THF was monitored by 77Se NMR and shown to give the novel cyclic selenium imide Se3(NAd)2 as one of the products. An X-ray structural determination showed that Se3(NAd)2 is a puckered five-membered ring with d(Se−Se) = 2.404(1) Å and |d(Se−N)| = 1.873(4) Å. On the basis of 77Se NMR data, other decomposition products include the six-membered ring Se3(NAd)3, and the four-membered rings AdNSe(μ-NAd)2SeO and OSe(μ-NAd)2SeO. The energies for the cyclodimerization of E(NR)2 and RNEO (E = S, Se; R = H, Me, tBu, SiMe3), and the cycloaddition reactions of RNSeO with E(NR)2, RNSO2 with Se(NR)2, and S(NR)2 with Se(NR)2 have been calculated at…
P4Well Concept to Empower Self-Management of Psychophysiological Wellbeing and Load Recovery
2009
Chronic health problems related to mental wellbeing are rapidly growing, calling for novel solutions focusing on individual as a psychophysiological being. We describe a novel technology-based concept for empowering citizen towards holistic self-management of her wellbeing: “P4Well” (Pervasive Personal and PsychoPhysiological management of WELLness). The primary focus of the concept is on management of stress and recovery from stress caused by daily life through improved health management strategies. The P4Well concept combines modern psychological methods with personal health technologies. The technologies include a web-portal and web-based tools, mobile phone with mobile client applicatio…
Awaking the motivation for change : relationships between physical fitness, physical activity and psychosocial factors among men in the Adventures of…
2017
This thesis examined how physical fitness is associated with self-reported physical activity (PA), eating habits and psychosocial factors among Finnish men who engaged in the Adventures of Joe Finn Campaign. The thesis comprises four original publications and supplementary results. The research framework utilizes the Health Action Process Approach (HAPA) and principles of social marketing. HAPA guides the explanation of health behaviors at the individual level within the wider framework of social marketing, which links the individual-level effects with the campaign. Data were collected during the Adventures of Joe Finn Campaign tour in 2011 and by a post-campaign e-mail survey in 2014. Phys…
Sex-specific signatures of intrinsic hippocampal networks and regional integrity underlying cognitive status in multiple sclerosis
2021
Abstract The hippocampus is an anatomically compartmentalized structure embedded in highly wired networks that are essential for cognitive functions. The hippocampal vulnerability has been postulated in acute and chronic neuroinflammation in multiple sclerosis, while the patterns of occurring inflammation, neurodegeneration or compensation have not yet been described. Besides focal damage to hippocampal tissue, network disruption is an important contributor to cognitive decline in multiple sclerosis patients. We postulate sex-specific trajectories in hippocampal network reorganization and regional integrity and address their relationship to markers of neuroinflammation, cognitive/memory per…
SingleChannelNet : A model for automatic sleep stage classification with raw single-channel EEG
2022
In diagnosing sleep disorders, sleep stage classification is a very essential yet time-consuming process. Various existing state-of-the-art approaches rely on hand-crafted features and multi-modality polysomnography (PSG) data, where prior knowledge is compulsory and high computation cost can be expected. Besides, it is a big challenge to handle the task with raw single-channel electroencephalogram (EEG). To overcome these shortcomings, this paper proposes an end-to-end framework with a deep neural network, namely SingleChannelNet, for automatic sleep stage classification based on raw single-channel EEG. The proposed model utilizes a 90s epoch as the textual input and employs two multi-conv…
Sleep Disturbances in COPD are Associated with Heterogeneity of Airway Obstruction
2018
Individuals with Chronic Obstructive Pulmonary Disease (COPD) experience sleep disturbances due to the impact of respiratory symptoms on sleep quality. We explored whether sleep disturbances in COPD are linked to heterogeneity of airway constriction.The impact of breathing problems on sleep quality was measured in consecutive COPD outpatients with the COPD and Asthma Sleep Impact Scale (CASIS) questionnaire. Impulse oscillometry technique (IOS) was employed to assess heterogeneity of airway constriction. Subjects with a previous or concomitant diagnosis of asthma or obstructive sleep apnea (OSA) were excluded.Fifty COPD subjects (M/F 40/10; age: 71 +/- 8 yrs, Body Mass Index (BMI): 26.2 +/-…