Self-interacting dark matter and the delay of supermassive black hole growth

Using cosmological hydrodynamic simulations with physically motivated models of supermassive black hole (SMBH) formation and growth, we compare the assembly of Milky Way-mass (Mvir ≈ 7 × 1011 M⊙ at z = 0) galaxies in cold dark matter (CDM) and self-interacting dark matter (SIDM) models. Our SIDM model adopts a constant cross-section of 1 cm2 g−1. We find that SMBH formation is suppressed in the early Universe due to SIDM interactions. SMBH–SMBH mergers are also suppressed in SIDM as a consequence of the lower number of SMBHs formed. Lack of initial merger-driven SMBH growth in turn delays SMBH growth by billions of years in SIDM compared to CDM. Further, we find that this delayed growth suppresses SMBH accretion in the largest progenitors of the main SIDM galaxies during the first 5 Gyr of their evolution. Nonetheless, by z = 0.8 the CDM and SIDM SMBH masses differ only by around 0.2 dex, so that both remain compatible with the MBH–M* relation. We show that the reduced accretion causes the SIDM SMBHs to less aggressively regulate star formation in their host galaxies than their CDM counterparts, resulting in a factor of 3 or more stars being produced over the lifetime of the SIDM galaxies compared to the CDM galaxies. Our results highlight a new way in which SIDM can affect the growth and merger history of SMBHs and ultimately give rise to very different galaxy evolution compared to the classic CDM model

Selenium as adjunct to HAART in the management of HIV/Hepatitis B Virus coinfection: A Randomized open label study

Objective: Management of viral hepatitis in patients with HIV disease is quite challenging and  complex. With effective HIV treatment, people with HIV/HBV co-infection are living longer. HBV  epidemiologic surveys showed an inverse association between selenium (Se) level and regional cancer incidence, as well as viral infection. This study assessed effect of selenium as adjunct to HAART in management of HIV/HBV co-infection.Methods: A randomized open label study with participants allocated into three treatment groups: – HAART-only, Se-only and HAART-plus-Se. HIV viral load, HBV viral load, CD4 cell count, and alanine aminotransaminase (ALT), were analyzed at baseline and 18th month, analyzed using SPSS 5 v11. Ethical approval was obtained from Institute’s Ethical Review Board.Results: Sample size was 149 HIV/HBV patients. Rate of HBV clearance was higher among those on HAART-plus-Se at 18th month when compared with rate of clearance among those on HAART-only (p=0.046). CD4 count increment among HAARTplus- Se group compared with HAART-only group was higher (p=0.133), though not statistically significant. On comparison of baseline and 18th month ALT, there was significant decline for HAART-plus-Se (p=0.002) compared with HAART-only group.Conclusion: Selenium seems to have protective effect on liver cells; may be beneficial as adjunct to HAART in HIV/HBV management.Key words: HIV/HBV co-infection, Selenium adjunct, HAAR

A database of whole-body action videos for the study of action, emotion, and untrustworthiness

We present a database of high-definition (HD) videos for the study of traits inferred from whole-body actions. Twenty-nine actors (19 female) were filmed performing different actions—walking, picking up a box, putting down a box, jumping, sitting down, and standing and acting—while conveying different traits, including four emotions (anger, fear, happiness, sadness), untrustworthiness, and neutral, where no specific trait was conveyed. For the actions conveying the four emotions and untrustworthiness, the actions were filmed multiple times, with the actor conveying the traits with different levels of intensity. In total, we made 2,783 action videos (in both two-dimensional and three-dimensional format), each lasting 7 s with a frame rate of 50 fps. All videos were filmed in a green-screen studio in order to isolate the action information from all contextual detail and to provide a flexible stimulus set for future use. In order to validate the traits conveyed by each action, we asked participants to rate each of the actions corresponding to the trait that the actor portrayed in the two-dimensional videos. To provide a useful database of stimuli of multiple actions conveying multiple traits, each video name contains information on the gender of the actor, the action executed, the trait conveyed, and the rating of its perceived intensity. All videos can be downloaded free at the following address: http://www-users.york.ac.uk/~neb506/databases.html. We discuss potential uses for the database in the analysis of the perception of whole-body actions

The course of mental health problems in children presenting with abdominal pain in general practice

Objective. To investigate the course of mental health problems in children presenting to general practice with abdominal pain and to evaluate the extent to which abdominal pain characteristics during follow-up predict the presence of mental health problems at 12 months' follow-up. Design. A prospective cohort study with one-year follow-up. Setting. 53 general practices in the Netherlands, between May 2004 and March 2006. Subjects. 281 children aged 4-17 years. Main outcome measures. The presence of a depressive problem, an anxiety problem, and multiple non-specific somatic symptoms at follow-up and odds ratios of duration, frequency, and severity of abdominal pain with these mental health problems at follow-up. Results. A depressive problem persisted in 24/74 children (32.9%; 95% CI 22.3-44.9%), an anxiety problem in 13/43 (30.2%; 95% CI 17.2-46.1%) and the presence of multiple non-specific somatic symptoms in 75/170 children (44.1%; 95% CI 36.7-51.6%). None of the abdominal pain characteristics predicted a depressive or an anxiety problem at 12 months' follow-up. More moments of moderate to severe abdominal pain predicted the presence of multiple nonspecific somatic symptoms at follow-up. Conclusions. In one-third of the children presenting to general practice for abdominal pain, anxiety and depressive problems persist during one year of follow-up. Characteristics of the abdominal pain during the follow-up period do not predict anxiety or depressive problems after one-year follow-up. We recommend following over time children seen in primary care with abdominal pain

Anomaly-Free Supersymmetric SO(2N+2)/U(N+1) sigma-Model Based on the SO(2N+1) Lie Algebra of the Fermion Operators

The extended supersymmetric (SUSY) sigma-model has been proposed on the bases of SO(2N+1) Lie algebra spanned by fermion annihilation-creation operators and pair operators. The canonical transformation, extension of an SO(2N) Bogoliubov transformation to an SO(2N+1) group, is introduced. Embedding the SO(2N+1) group into an SO(2N+2) group and using SO(2N+2)/U(N+1) coset variables, we have investigated the SUSY sigma-model on the Kaehler manifold, the coset space SO(2N+2)/U(N+1). We have constructed the Killing potential, extension of the potential in the SO(2N)/U(N) coset space to that in the SO(2N+2)/U(N+1) coset space. It is equivalent to the generalized density matrix whose diagonal-block part is related to a reduced scalar potential with a Fayet-Ilipoulos term. The f-deformed reduced scalar potential is optimized with respect to vacuum expectation value of the sigma-model fields and a solution for one of the SO(2N+1) group parameters has been obtained. The solution, however, is only a small part of all solutions obtained from anomaly-free SUSY coset models. To construct the coset models consistently, we must embed a coset coordinate in an anomaly-free spinor representation (rep) of SO(2N+2) group and give corresponding Kaehler and Killing potentials for an anomaly-free SO(2N+2)/U(N+1) model based on each positive chiral spinor rep. Using such mathematical manipulation we construct successfully the anomaly-free SO(2N+2)/U(N+1) SUSY sigma-model and investigate new aspects which have never been seen in the SUSY sigma-model on the Kaehler coset space SO(2N)/U(N). We reach a f-deformed reduced scalar potential. It is minimized with respect to the vacuum expectation value of anomaly-free SUSY sigma-model fields. Thus we find an interesting f-deformed solution very different from the previous solution for an anomaly-free SO(2.5+2)/(SU(5+1)*U(1)) SUSY sigma-model.Comment: 24 pages, no fiure

An instability criterion for nonlinear standing waves on nonzero backgrounds

A nonlinear Schr\"odinger equation with repulsive (defocusing) nonlinearity is considered. As an example, a system with a spatially varying coefficient of the nonlinear term is studied. The nonlinearity is chosen to be repelling except on a finite interval. Localized standing wave solutions on a non-zero background, e.g., dark solitons trapped by the inhomogeneity, are identified and studied. A novel instability criterion for such states is established through a topological argument. This allows instability to be determined quickly in many cases by considering simple geometric properties of the standing waves as viewed in the composite phase plane. Numerical calculations accompany the analytical results.Comment: 20 pages, 11 figure

Metabolomic Analysis of Campylobacter jejuni by Direct-Injection Electrospray Ionization Mass Spectrometry

Direct-injection mass spectrometry (DIMS) is a means of rapidly obtaining metabolomic phenotype data in both prokaryotes and eukaryotes. Given our generally poor understanding of Campylobacter metabolism, the high-throughput and relatively simple sample preparation of DIMS has made this an attractive technique for metabolism-related studies and hypothesis generation, especially when attempting to analyze metabolic mutants with no clear phenotype. Here we describe a metabolomic fingerprinting approach with sampling and extraction methodologies optimized for direct-injection electrospray ionization mass spectrometry (ESI-MS), which we have used as a means of comparing wild-type and isogenic mutant strains of C. jejuni with various metabolic blocks

Metabolomic Analysis of Campylobacter jejuni by Direct-Injection Electrospray Ionization Mass Spectrometry

Direct-injection mass spectrometry (DIMS) is a means of rapidly obtaining metabolomic phenotype data in both prokaryotes and eukaryotes. Given our generally poor understanding of Campylobacter metabolism, the high-throughput and relatively simple sample preparation of DIMS has made this an attractive technique for metabolism-related studies and hypothesis generation, especially when attempting to analyze metabolic mutants with no clear phenotype. Here we describe a metabolomic fingerprinting approach with sampling and extraction methodologies optimized for direct-injection electrospray ionization mass spectrometry (ESI-MS), which we have used as a means of comparing wild-type and isogenic mutant strains of C. jejuni with various metabolic blocks

MicroRNA-181b Controls Atherosclerosis and Aneurysms Through Regulation of TIMP-3 and Elastin

Rationale: Atherosclerosis and aneurysms are leading causes of mortality worldwide. MicroRNAs (miRs) are key determinants of gene and protein expression, and atypical miR expression has been associated with many cardiovascular diseases; although their contributory role to atherosclerotic plaque and abdominal aortic aneurysm stability are poorly understood. Objective: To investigate whether miR-181b regulates tissue inhibitor of metalloproteinase-3 expression and affects atherosclerosis and aneurysms. Methods and Results: Here, we demonstrate that miR-181b was overexpressed in symptomatic human atherosclerotic plaques and abdominal aortic aneurysms and correlated with decreased expression of predicted miR-181b targets, tissue inhibitor of metalloproteinase-3, and elastin. Using the well-characterized mouse atherosclerosis models of Apoe−/− and Ldlr−/−, we observed that in vivo administration of locked nucleic acid anti-miR-181b retarded both the development and the progression of atherosclerotic plaques. Systemic delivery of anti-miR-181b in angiotensin II– infused Apoe−/− and Ldlr−/− mice attenuated aneurysm formation and progression within the ascending, thoracic, and abdominal aorta. Moreover, miR-181b inhibition greatly increased elastin and collagen expression, promoting a fibrotic response and subsequent stabilization of existing plaques and aneurysms. We determined that miR-181b negatively regulates macrophage tissue inhibitor of metalloproteinase-3 expression and vascular smooth muscle cell elastin production, both important factors in maintaining atherosclerotic plaque and aneurysm stability. Validation studies in Timp3−/− mice confirmed that the beneficial effects afforded by miR-181b inhibition are largely tissue inhibitor of metalloproteinase-3 dependent, while also revealing an additional protective effect through elevating elastin synthesis. Conclusions: Our findings suggest that the management of miR-181b and its target genes provides therapeutic potential for limiting the progression of atherosclerosis and aneurysms and protecting them from rupture

Efficacy and tolerability of α-galactosidase in treating gas-related symptoms in children: a randomized, double-blind, placebo controlled trial

BACKGROUND: Gas-related symptoms represent very common complaints in children. The reduction of gas production can be considered as a valuable target in controlling symptoms. α-galactosidase has been shown to reduce gas production and related symptoms in adults. To evaluate the efficacy and tolerability of α-galactosidase in the treatment of gas-related symptoms in pediatric patients. METHODS: Single center, randomized, double-blind, placebo-controlled, parallel group study performed in tertiary care setting. Fifty-two pediatric patients (32 female, age range 4–17) with chronic or recurrent gas-related symptoms were randomized to receive placebo (n = 25) or α-galactosidase (n = 27). Both treatments were given as drops or tablets, according to body weight for 2 weeks. The primary endpoint was the reduction in global distress measured by the Faces Pain Scale-Revised (FPS-R) at the end of treatment compared to baseline. Secondary endpoints were the reduction in severity and frequency of gas-related symptoms as recorded by parents and/or children. RESULTS: α-galactosidase significantly reduced global distress (p = 0.02) compared to placebo. The digestive enzyme decreased the number of days with moderate to severe bloating (p = 0.03) and the proportion of patients with flatulence (p = 0.02). No significant differences were found for abdominal spasms and abdominal distension. No adverse events were reported during treatment. CONCLUSIONS: Although larger and longer trials are needed to confirm this result, α-galactosidase seems to be a safe, well tolerated and effective treatment for gas-related symptoms in the pediatric population. TRIAL REGISTRATION: ClinicalTrials.gov, NCT0159593