Mass of galaxy lenses in modified gravity: any need for dark mass?

Using strong lensing data, Milgrom's modified Newtonian dynamics (MOND) and its covariant TeVeS (tensor-vector-scalar theory) are examined here as an alternative to the conventional ΛCDM paradigm. We examine 10 double-image, gravitational lensing systems in which the lens masses have been estimated by stellar population synthesis models. While mild deviations exist, we find no strong case of outliers to the TeVeS theory. © 2011 American Physical Society.published_or_final_versio

X-Ray afterglow of SWIFT J1644+57: a Compton echo?

postprin

Multi-wavelength Emission from the Fermi Bubble. II. Secondary Electrons and the Hadronic Model of the Bubble

published_or_final_versio

Origin of X-Ray and Gamma-Ray Emission from the Galactic Central Region

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Multi-wavelength Emission From The Fermi Bubbles. I. Stochastic Acceleration From Background Plasma

published_or_final_versio

Prevalence of allergic rhinitis and its associated morbidity in adults with asthma: A multicentre study

Objectives To assess the prevalence of allergic rhinitis in adult patients with asthma in Hong Kong, and to compare the morbidity endured by asthma patients with and without allergic rhinitis. Design Cross-sectional study. Setting Respiratory clinics of four major public hospitals in Hong Kong. Patients A total of 600 adults with asthma were recruited from March to May 2007. Main outcome measures Doctors and patients completed separate questionnaires evaluating symptoms, treatment, and health care utilisation. Spirometry data were obtained for a subgroup of patients at the time of survey completion. Results The patients consisted of 267 males and 333 females, with 251 having spirometry data. The mean pre-bronchodilator 1-second forced expiratory volume predicted among those who had spirometry performed was 88% (standard deviation, 28%). In all, 50% of the patients had intermittent and 50% had persistent asthma. Over three quarters (463/600; 77%) of patients had experienced allergic rhinitis symptoms in the past 12 months, of whom 96% had a previous diagnosis of allergic rhinitis. Asthmatics without allergic rhinitis symptoms had higher rates of visits to doctors, pharmacy visits, emergency department attendances, and hospitalisations for asthma than those with both conditions. Among subjects with asthma and allergic rhinitis, those taking nasal steroid (226/463; 49%) had lower rates of emergency department visits (13 vs 25%, P=0.002) and hospitalisations (7 vs 13%, P=0.045) for asthma than those who were not. Conclusion Allergic rhinitis is a common co-morbid condition of asthma in this hospital clinic cohort. Treatment of allergic rhinitis with intra-nasal steroid was associated with less health care utilisation for asthma.published_or_final_versio

Influence of ambient water intrusion on coral reef acidification in the Chuuk lagoon, located in the coral-rich western Pacific Ocean

Weekly carbonate chemistry condition data recorded between 2008 and 2014 in the Chuuk lagoon (7.3 degrees N and 151.5 degrees E) of the Federated States of Micronesia, located in the western Pacific Ocean, were analyzed. The results showed that, during periods of weak intrusion of ambient seawater from the surrounding open ocean, two internal biological processes (calcification and respiration) reinforced each other and together lowered the pH of the reef water for extended periods, ranging from a few to several months. The analysis indicated that reduced intrusion of ambient water is associated with periods of low wind speeds. Such conditions increase the residence time of reef water, thus promoting acidification by respiration and calcification. This phenomenon likely affects many other areas of the coral-rich western Pacific Ocean, which contains 50% of global coral reefs and in which the degree of ambient water intrusion into the atolls has been shown to be closely associated with the El Nino-Southern Oscillation-induced wind speed change.1111Ysciescopu

Antikaon production in nucleon-nucleon reactions near threshold

The antikaon production cross section from nucleon-nucleon reactions near threshold is studied in a meson exchange model. We include both pion and kaon exchange, but neglect the interference between the amplitudes. In case of pion exchange the antikaon production cross section can be expressed in terms of the antikaon production cross section from a pion-nucleon interaction, which we take from the experimental data if available. Otherwise, a $K^*$-resonance exchange model is introduced to relate the different reaction cross sections. In case of kaon exchange the antikaon production cross section is related to the elastic $KN$ and $\bar KN$ cross sections, which are again taken from experimental measurements. We find that the one-meson exchange model gives a satisfactory fit to the available data for the $NN\to NNK\bar K$ cross section at high energies. We compare our predictions for the cross section near threshold with an earlier empirical parameterization and that from phase space models.Comment: 16 pages, LaTeX, 5 postscript figures included, submitted to Z. Phys.

Classification of non-Riemannian doubled-yet-gauged spacetime

Assuming $\mathbf{O}(D,D)$ covariant fields as the `fundamental' variables, Double Field Theory can accommodate novel geometries where a Riemannian metric cannot be defined, even locally. Here we present a complete classification of such non-Riemannian spacetimes in terms of two non-negative integers, $(n,\bar{n})$, $0\leq n+\bar{n}\leq D$. Upon these backgrounds, strings become chiral and anti-chiral over $n$ and $\bar{n}$ directions respectively, while particles and strings are frozen over the $n+\bar{n}$ directions. In particular, we identify $(0,0)$ as Riemannian manifolds, $(1,0)$ as non-relativistic spacetime, $(1,1)$ as Gomis-Ooguri non-relativistic string, $(D{-1},0)$ as ultra-relativistic Carroll geometry, and $(D,0)$ as Siegel's chiral string. Combined with a covariant Kaluza-Klein ansatz which we further spell, $(0,1)$ leads to Newton-Cartan gravity. Alternative to the conventional string compactifications on small manifolds, non-Riemannian spacetime such as $D=10$, $(3,3)$ may open a new scheme of the dimensional reduction from ten to four.Comment: 1+41 pages; v2) Refs added; v3) Published version; v4) Sign error in (2.51) correcte