ESR spectral change of radicals produced in L-alanine-3,3,3-d3 and L-alanine-d4. -A new pathway to produce the de-hydrogen radical and the hydrogen exchange reactions of the de-amino radical-

Publication date: Available online 20 July 2019Source: Radiation Physics and ChemistryAuthor(s): Seiko NakagawaAbstractRadicals produced in L-alanine-3,3,3-d3 and L-alanine-d4 by X-irradiation and their spectral change were investigated using X-band ESR. Apparently, two major radicals appeared. One is the radical formed by deamination from a protonated anion and the other is produced by the loss of an alpha hydrogen. Before the appearance of the de-hydrogen radical, the precursor radical with a singlet feature was observed at 148–158 K. The signal of the precursor decreased and that of the de-hydrogen radical increased with temperature. Because the feature of the precursor radical was a singlet, it will be produced by deprotonation of the alpha hydrogen from the deprotonated cation radical observed at 77–80 K. Protonation to the amine moiety of the deprotonated radical will be a new pathway to produce the de-hydrogen radical.In L-alanine-3,3,3-d3, the hydrogen exchange reaction between the alpha hydrogen in the de-amino radical and the beta deuterium in a neighboring molecule occurred at the first-order rate of 7 × 10−4 s−1 at 294 K. The activation energy was 25 kcal/mol. By annealing at 393 K, the spectral features have obviously changed by the hydrogen exchange reactions in the de-amino radicals. Finally, all the de-amino radicals changed to •CHCH3COOH(D) and the methyl deuterium in the de-hydrogen radicals changed to hyd...
Source: Radiation Physics and Chemistry - Category: Physics Source Type: research

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CONCLUSIONS: Combining the network analysis approach with the mediation analyses provides for the first time a putative hybrid model, which reveals that all CM types converge towards ED symptoms through emotional abuse and that interoceptive awareness and ineffectiveness mediate these connections in people with ANR and BP symptoms, respectively. These findings may have possible implications for both research and treatment of EDs. PMID: 31437672 [PubMed - as supplied by publisher]
Source: Journal of the Association of European Psychiatrists - Category: Psychiatry Tags: Eur Psychiatry Source Type: research
Authors: Hengartner MP, Davies J, Read J Abstract Withdrawal reactions when coming off antidepressants have long been neglected or minimised. It took almost two decades after the selective serotonin reuptake inhibitors (SSRIs) entered the market for the first systematic review to be published. More reviews have followed, demonstrating that the dominant and long-held view that withdrawal is mostly mild, affects only a small minority and resolves spontaneously within 1-2 weeks, was at odd with the sparse but growing evidence base. What the scientific literature reveals is in close agreement with the thousands of serv...
Source: Epidemiology and Psychiatric Sciences - Category: Psychiatry Tags: Epidemiol Psychiatr Sci Source Type: research
Authors: Ma F, Lv X, Du Y, Chen H, Liu S, Zhao J, Gao Y, An P, Zhou X, Song A, Sun C, Wang G, Ji Y, Wang X, Xu W, Huang G Abstract BACKGROUND: Leukocyte telomere length (LTL) is associated with the aging process and age-related degenerative diseases. The relation of peripheral blood LTL to mild cognitive impairment (MCI) and Alzheimer's disease (AD) and the role of folate and homocysteine (Hcy) in this relation remain unclear. OBJECTIVES: We aimed to investigate the association between LTL and the risks of MCI/AD, and to explore whether folate and Hcy may play a role in this association. METHODS: This case-...
Source: Dementia and Geriatric Cognitive Disorders - Category: Psychiatry Tags: Dement Geriatr Cogn Disord Source Type: research
Authors: Sue S Abstract The research articles in this special issue edited by Zamboanga and Lui focus on sociocultural factors and processes that underlie ethnic disparities in alcohol use in the United States. Major ethnic minority groups such as African Americans, Asian Americans, and Hispanics are included. Contributors to this special issue present their research findings and draw implications for research, theory, and intervention. The focus is clearly needed. We know enough to say that serious alcohol-use disparities exist; finding effective solutions to these problems is vitally important, especially in our ...
Source: The American Journal of Orthopsychiatry - Category: Psychiatry Tags: Am J Orthopsychiatry Source Type: research
Authors: Lui PP, Zamboanga BL Abstract Hazardous alcohol use is associated with deleterious health effects and social consequences, reduced work productivity, and increased medical and criminal justice expenditures. Research has consistently shown not only ethnic differences in prevalence rates of drinking behaviors and alcohol use disorders but also negative alcohol-related consequences and treatment-seeking patterns. Mainstream alcohol research has tended to focus on determinants and mechanisms that are common across ethnocultural groups; hence, there are tremendous opportunities to address issues that are especi...
Source: The American Journal of Orthopsychiatry - Category: Psychiatry Tags: Am J Orthopsychiatry Source Type: research
Authors: Li B, He Y, Ma J, Huang P, Du J, Cao L, Wang Y, Xiao Q, Tang H, Chen S Abstract OBJECTIVE: Gut microbiota changes before the onset of Alzheimer's disease (AD) and the alterations could be detected in the stage of mild cognitive impairment (MCI). The findings might offer diagnostic biomarkers before the onset of dementia. BACKGROUND: AD is the most common cause of dementia, and MCI is the predementia state. Recent studies suggest the alterations in the gut microbial communities associated with AD, whereas the microbiota in MCI before the onset of dementia has not been discovered and characterized in hum...
Source: The Journal of Alzheimers Association - Category: Psychiatry Tags: Alzheimers Dement Source Type: research
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Source: The Journal of American Association of Directors of Psychiatric Residency Training - Category: Psychiatry Tags: Acad Psychiatry Source Type: research
Publication date: Available online 22 August 2019Source: Reactive and Functional PolymersAuthor(s): Yubin Li, Zhijian Yang, Ling Ding, Liping Pan, Jianhu Zhang, Xue Zheng, Congmei LinAbstractDamages generated in functional materials can deteriorate their performance and shorten their lifetime, endowing the materials with self-healing ability is expected to resolve this problem. In this work, a novel energetic composite refers to CL-20 based PBX, which can self-heal its mechanical damage under a mild condition, was designed and prepared via incorporating disulfide bonds into the polymeric binder. The highly efficient self-h...
Source: Reactive and Functional Polymers - Category: Chemistry Source Type: research
Publication date: Available online 22 August 2019Source: PolymerAuthor(s): Marcin Jesionek, Bartłomiej Toroń, Piotr Szperlich, Włodzimierz Biniaś, Dorota Biniaś, Stanisław Rabiej, Anna Starczewska, Marian Nowak, Mirosława Kępińska, Jan DecAbstractIn this paper, a new fabrication method for Polyvinylidene fluoride/SbSI nanowire composite is presented. Polyvinylidene fluoride (PVDF) is a specialist thermoplastic fluoropolymer with very good mechanical, chemical and thermal properties. Additionally, PVDF shows piezoelectric, pyroelectric, and ferroelectric properties. Antimony sulfoiodide (SbSI) nanowires (lateral di...
Source: Polymer - Category: Chemistry Source Type: research
Publication date: Available online 22 August 2019Source: PolymerAuthor(s): Yaxin Qiu, Qianru Wanyan, Wenyuan Xie, Zhifeng Wang, Ming Chen, Defeng WuAbstractAn interesting biomass-derived shape memory polymer (SMP) based on cross-linked poly(l-malic acid) (PMA), with reconfigurable permanent shape and tunable shape memory transition temperature (Ttrans), was developed in this work. The amorphous cross-linked network was constructed in PMA using eco-friendly 1,8-octanediol as the cross-linker through a catalyst-free two-step way. The relations between crosslinking density (d) and glass transition temperature (Tg), as well as...
Source: Polymer - Category: Chemistry Source Type: research
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