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Abstract: The effects of carbonization process and carbon nanofiber/nanotube additives on the cycling stability of silicon–carbon composite anodes were investigated by monitoring the impedance evolution during charge/discharge cycles with electrochemical impedance spectroscopy (EIS). Three types of Si–C anodes were investigated: the first type consisted of Si nanoparticles incorporated into a network of carbon nanofibers (CNFs) and multi-walled carbon nanotubes (MWNTs), with annealed polymer binder. The second type of Si–C anodes was prepared by further heat treatment of the first Si–C anodes to carbonize the polymer binder. The third Si–C anode was as same as the second one except no CNFs and MWNTs being added. Impedance analysis revealed that the carbonization process stabilized the Si–C anode structure and decreased the charge transfer resistance, thus improving the cycling stability. On the other hand, although the MWNTs/CNFs additives could enhance the electronic conductivity of the Si–C anodes, the induced inhomogeneous structure decreased the integrity of the electrode, resulting in a poor long term cycling stability. [Copyright &y& Elsevier]

Changes in cyclic nucleotide production and atrial dynamics have been known to modulate atrial natriuretic peptide (ANP) release. Although cardiac atrium expresses histamine receptors and contains histamine, the role of histamine in the regulation of ANP release has to be defined. The purpose of the present study was to define the effect of histamine on the regulation of ANP release in perfused beating rabbit atria. Histamine decreased ANP release concomitantly with increases in cAMP efflux and atrial dynamics in a concentration-dependent manner. Histamine-induced decrease in ANP release was a function of an increase in cAMP production. Blockade of histamine H2 receptor with cimetidine but not of H1 receptor with triprolidine abolished the responses of histamine. Cell-permeable cAMP analog, 8-Br-cAMP, mimicked the effects of histamine, and the responses were dose-dependent and blocked by a protein kinase A (PKA)-selective inhibitor, KT5720. Nifedipine failed to modulate histamine-induced decrease in ANP release. Protein kinase nonselective inhibitor staurosporine blocked histamine-induced changes in a concentration-dependent manner. KT5720 and RP-adenosine 3',5'-cyclic monophosphorothioate, another PKA-selective inhibitor, attenuated histamine-induced changes. These results suggest that histamine decreases atrial ANP release by H2 receptor-cAMP signaling via PKA-dependent and -independent pathways. [ABSTRACT FROM AUTHOR]

Presents information on body dysmorphic disorder. Definitions and etiology; Illustrative cases; Clinical manifestations; Treatment; Clinical implications in primary care.

Objective: The aging of the baby boomer generation has led to an unprecedented rise in the number of US adults reaching old age, prompting an urgent call for innovative and cost-effective ways to address the increasing health care needs of the aging population. Studying the role of psychosocial factors on health care use could offer insight into how to minimize hospitalizations among older adults., Methods: We use prospective data from a subsample of 4735 participants (mean [standard deviation] age = 69 [8.79] years, 61% women) from the Health and Retirement Study, a nationally representative study of US adults over age 50, to examine the association between self-perceptions of aging (SPA) and self-reported overnight hospitalizations after adjusting for a comprehensive list of sociodemographic, health-related, and behavioral factors., Results: Over the 4-year follow-up period, there were a total of 5196 overnight hospitalizations, and 44% of the sample reported being hospitalized overnight at least once. After adjusting for sociodemographic factors, each standard deviation increase in positive SPA was associated with a lower rate of overnight hospitalization (incidence rate ratio = 0.75; 95% confidence interval = 0.71-0.80, p < .001). After dividing respondents into quartiles of SPA, we observed a dose-response relationship with individuals in higher quartiles showing increasingly lower rates of overnight hospitalization., Conclusions: Positive self-perceptions of aging are associated with a lower rate of hospitalization among older adults over a 4-year period. Future research should examine the factors that contribute to older adults' SPA and explore the pathways through which attitudes toward aging influence the use of health care resources., Competing Interests: The authors have no conflicts of interest to disclose.