Galaxy alignment on large and small scales

Galaxies are not randomly distributed across the universe but showing different kinds of alignment on different scales. On small scales satellite galaxies have a tendency to distribute along the major axis of the central galaxy, with dependence on galaxy properties that both red satellites and centrals have stronger alignment than their blue counterparts. On large scales, it is found that the major axes of Luminous Red Galaxies (LRGs) have correlation up to 30Mpc/h. Using hydro-dynamical simulation with star formation, we investigate the origin of galaxy alignment on different scales. It is found that most red satellite galaxies stay in the inner region of dark matter halo inside which the shape of central galaxy is well aligned with the dark matter distribution. Red centrals have stronger alignment than blue ones as they live in massive haloes and the central galaxy-halo alignment increases with halo mass. On large scales, the alignment of LRGs is also from the galaxy-halo shape correlation, but with some extent of mis-alignment. The massive haloes have stronger alignment than haloes in filament which connect massive haloes. This is contrary to the naive expectation that cosmic filament is the cause of halo alignment.Comment: 4 pages, 3 figures, To appear in the proceedings of the IAU Symposium 308 "The Zeldovich Universe: Genesis and Growth of the Cosmic Web

Adsorption/desorption and electrically controlled flipping of ammonia molecules on graphene

In this paper, we evaluate of the adsorption/ desorption of ammonia molecules on a graphene surface by studying the Fermi level shift. Based on a physically plausible model, the adsorption and desorption rates of ammonia molecules on graphene have been extracted from the measured Fermi level shift as a function of exposure time. An electric field-induced flipping behavior of ammonia molecules on graphene is suggested, based on field effect transistor (FET) measurements

Prevalence and determinants of anxiety and depression in end stage renal disease (ESRD). A comparison between ESRD patients with and without coexisting diabetes mellitus

Objective: To compare anxiety and/or depressive symptoms between patients with end-stage renal disease with and without comorbid diabetes and identify factors associated with symptoms of distress in this population. Methods: Data from two studies (conducted between 2010 and 2014) were pooled. A total of 526 patients on hemodialysis (68.8% with diabetes) completed the Hospital Anxiety and Depression Scale (HADS). Elevated symptoms were defined as HADS-Anxiety or HADS-Depression ≥ 8. Univariate and multivariate logistic regressions were used to estimate associations between diabetic status, and other socio-demographic and clinical factors with baseline clinical anxiety and depression. Results: A total of 233 (45.4%) reported elevated anxiety symptoms and 256 (49.9%) reported elevated depressive symptoms sufficient for caseness. Rates were not different between patients with and without diabetes. Risk for clinical depression was higher in patients who were single/unpartnered (OR = 1.828), Chinese vs. Malay (OR = 2.05), or had lower albumin levels (OR = 0.932). None of the parameters were associated with anxiety caseness. Conclusion: Sociocultural factors rather than comorbid burden may help identify patients at risk for depression. The high rates of anxiety and depression underlie the importance for monitoring and intervention in dialysis care

The adsorption of phosphate using a magnesia–pullulan composite: Kinetics, equilibrium, and column tests

© Springer-Verlag GmbH Germany, part of Springer Nature 2019. Amagnesia–pullulan (MgOP) composite has been developed to remove phosphate from a synthetic solution. In the present study, the removal of phosphate by MgOP was evaluated in both a batch and dynamic system. The batch experiments investigated the initial pH effect on the phosphate removal efficiency from pH 3 to 12 and the effect of co-existing anions. In addition, the adsorption isotherms, thermodynamics, and kinetics were also investigated. The results from the batch experiments indicate that MgOP has encouraging performance for the adsorption of phosphate, while the initial pH value (3–12) had a negligible influence on the phosphate removal efficiency. Analysis of the adsorption thermodynamics demonstrated that the phosphate removal process was endothermic and spontaneous. Investigations into the dynamics of the phosphate removal process were carried out using a fixed bed of MgOP, and the resulting breakthrough curves were used to describe the column phosphate adsorption process at various bed masses, volumetric flow rates, influent phosphate concentrations, reaction temperatures, and inlet pH values. The results suggest that the adsorption of phosphate on MgOP was improved using an increased bed mass, while the reaction temperature did not significantly affect the performance of the MgOP bed during the phosphate removal process. Furthermore, higher influent phosphate concentrations were beneficial towards increasing the column adsorption capacity for phosphate. Several mathematic models, including the Adams–Bohart, Wolboska, Yoon–Nelson, and Thomas models, were employed to fit the fixed-bed data. In addition, the effluent concentration of magnesium ions was measured and the regeneration of MgOP investigated

Acoustic comfort in large railway stations

Large railway stations attract a wide range of passengers and citizens, and these buildings are likely to have a complex acoustic environment. Previous studies have focused on reducing people’s exposure to excessive sound levels caused by transportation, but more research is needed to assess people’s preferences and ensure their psychophysical wellbeing. The aim of this study was to explore the complex aspects of the sound environment in large railway stations that contribute to acoustic comfort. On-site measurements and an acoustic comfort survey were performed at a case study site in Harbin, China. The results showed a significant positive correlation between the subjective comfort evaluations and objective measurements of the sound pressure level and reverberation time. Differences in dominant sound sources in different spaces lead to different evaluations of acoustic comfort. People prefer broadcast sound, but its intelligibility needs to be improved. When the density of people increases, the preference for speech sounds and activity sounds decline rapidly. With regard to demographic and social factors, older people and people with higher incomes and education levels are more tolerant of the environment. As railway transportation has become modernized, large railway stations now play an important role in civic architecture. The aim of this study was to explore the effects of sound sources on the sound environment and acoustic comfort in such an extra-large space. Based on subjective and objective measurements of a typical railway station in China that has an extra-large space and multiple sound sources, the effects of sound sources in different functional zones were studied. The overall acoustic comfort and sound pressure levels were related to the sonic composition of the sound sources. The roles of various individual sound sources were investigated, including the speech sounds of other passengers in the seating area, the speech sounds of staff, the sounds of placing luggage in the security scan machine in the security check area, the sounds of a ticket machine in the ticket lobby, and the speech sounds of restaurant workers. The sound sources that have dominant impacts on the survey participants' evaluations of acoustic comfort were determined. In terms of acoustic comfort, broadcast sound was the most preferable, whereas mechanical noise and luggage noise were the least preferable. The sound levels of speech, the intelligibility of both broadcast and speech sounds, and the loudness of the three dominant sound sources exhibited a linear correlation with the sound pressure level. In terms of the effect of the sound characteristics on acoustic comfort, the sound level of speech was the dominant factor. Overall, acoustic comfort can be effectively improved by better planning of the combination and arrangement of sound sources

Triple sign reversal of Hall effect in HgBa_{2}CaCu_{2}O_{6} thin films after heavy-ion irradiations

Triple sign reversal in the mixed-state Hall effect has been observed for the first time in ion-irradiated HgBa_{2}CaCu_{2}O_{6} thin films. The negative dip at the third sign reversal is more pronounced for higher fields, which is opposite to the case of the first sign reversal near T_c in most high-T_c superconductors. These observations can be explained by a recent prediction in which the third sign reversal is attributed to the energy derivative of the density of states and to a temperature-dependent function related to the superconducting energy gap. These contributions prominently appear in cases where the mean free path is significantly decreased, such as our case of ion-irradiated thin films.Comment: 4 pages, 3 eps figures, submitted Phys. Rev. Let