The new interaction suggested by the anomalous 8^8Be transition sets a rigorous constraint on the mass range of dark matter

The WIMPs are considered one of the favorable dark matter (DM) candidates, but as the upper bounds on the interactions between DM and standard model (SM) particles obtained by the upgraded facilities of DM direct detections get lower and lower. Researchers turn their attentions to search for less massive DM candidates, i.e. light dark matter of MeV scale. The recently measured anomalous transition in $^8$Be suggests that there exists a vectorial boson which may mediate the interaction between DM and SM particles. Based on this scenario, we combine the relevant cosmological data to constrain the mass range of DM, and have found that there exists a model parameter space where the requirements are satisfied, a range of $10.4 \lesssim m_{\phi} \lesssim$ 16.7 MeV for scalar DM, and $13.6 \lesssim m_{V} \lesssim$ 16.7 MeV for vectorial DM is demanded. Then a possibility of directly detecting such light DM particles via the DM-electron scattering is briefly studied in this framework.Comment: 13 Pages, 7 figures, references added, version accepted by journa

The Mind-Body Connection: Exploring the Defining Characteristics of Two Aging Phenotypes

Introduction: Built on the theory of mind-body connection, there has been a growing interest in phenotypes combining physical frailty and cognitive decline. Two examples are motoric cognitive risk syndrome (MCR) and cognitive frailty (CF). MCR, defined by co-presentation of slow gait and subjective cognitive complaint without dementia or mobility disability, is considered a “pre-dementia syndrome.” CF, defined as having both physical frailty and cognitive impairment in the absence of dementia, is posited to be caused by physical frailty. Although both MCR and CF have been associated with dementia risk, the relationship between the two is unknown. We aimed to (1) assess the concordance between the two, and (2) describe the characteristics of those with MCR or CF or both. By doing so, we hope to move beyond risk prediction towards a better understanding of heterogeneity in cognitive decline. Methods: The analysis uses baseline data (year 2011) from the National Health and Aging Trend Study. Frailty was measured by the physical frailty phenotype. Cognitive impairment was based on self/proxy report of dementia and cognitive performance tests. We first estimated the prevalence of 3 groups: having MCR only, having CF only and having both MCR and CF. Next, we examined the associations between group membership and demographic/health characteristics using multinomial logistic regression. Results: Of the 6,212 eligible subjects, 304 had MCR only, 410 were CF only, and 115 had both. While 21.9% of those with CF had MCR, 27.5% of those with MCR had CF. Those who had both were more likely to be Blacks and Hispanics, in a lower socioeconomic status. The CF only group had a stronger association with comorbidity burden than MCR only. Health characteristics were more similar between the CF only group and the both group. The differences between the MCR only and the CF only were mostly due to the exclusion of mobility disability in the case of MCR. Conclusions: There are noteworthy areas of discordance between MCR and CF. The exact etiology of their differences remains undetermined and it is unclear if these syndromes are measuring the same underlying process at different stages of advancement or entirely different pathological processes of cognitive decline

Synthesis and Sensing Properties of ZnO/ZnS Nanocages

Large-scale uniform ZnO dumbbells and ZnO/ZnS hollow nanocages were successfully synthesized via a facile hydrothermal route combined with subsequent etching treatment. The nanocages were formed through preferential dissolution of the twinned (0001) plane of ZnO dumbbells. Due to their special morphology, the hollow nanocages show better sensing properties to ethanol than ZnO dumbbells. The gain in sensitivity is attributed to both the interface between ZnO and ZnS heterostructure and their hollow architecture that promotes analyte diffusion and increases the available active surface area

The Influence of Bauschinger Effect in Straightening Process

The yield stress changes during the straightening process, because of the Bauschinger effect. This effect leads to a different reduction rate in each straightening roller. To accurately estimate the straightening effect of the rolled piece, the Bauschinger effect must be considered in calculating the reduction rate. In this paper, the straightening model is described by the fast multipole boundary element method. The Bauschinger effect model is discussed in the elastic loading region and elastic plastic loading region. Young’s modulus reduction and the reverse yield stress reduction are obtained for the straightening force model. The straightening force formula including the Bauschinger effect is determined by analyzing the tension and compression processes. This formula reflects the changes of the yield stress and the straightening force in the tension and compression processes. It is concluded that the Bauschinger effect is a very important factor for the precise estimation of the straightening force