Log canonical thresholds of quasi-ordinary hypersurface singularities

The log canonical thresholds of irreducible quasi-ordinary hypersurface singularities are computed, using an explicit list of pole candidates for the motivic zeta function found by the last two authors

Did Fomalhaut, HR 8799, and HL Tauri Form Planets via the Gravitational Instability? Placing Limits on the Required Disk Masses

Disk fragmentation resulting from the gravitational instability has been proposed as an efficient mechanism for forming giant planets. We use the planet Fomalhaut b, the triple-planetary system HR 8799, and the potential protoplanet associated with HL Tau to test the viability of this mechanism. We choose the above systems since they harbor planets with masses and orbital characteristics favored by the fragmentation mechanism. We do not claim that these planets must have formed as the result of fragmentation, rather the reverse: if planets can form from disk fragmentation, then these systems are consistent with what we should expect to see. We use the orbital characteristics of these recently discovered planets, along with a new technique to more accurately determine the disk cooling times, to place both lower and upper limits on the disk surface density--and thus mass--required to form these objects by disk fragmentation. Our cooling times are over an order of magnitude shorter than those of Rafikov (2005),which makes disk fragmentation more feasible for these objects. We find that the required mass interior to the planet's orbital radius is ~0.1 Msun for Fomalhaut b, the protoplanet orbiting HL Tau, and the outermost planet of HR 8799. The two inner planets of HR 8799 probably could not have formed in situ by disk fragmentation.Comment: 5 pages, 1 figure, accepted for publication in ApJ

Seni Bordir Tasikmalaya dalam Konstelasi Estetik dan Identitas

Penelitian ini berjudul “Seni Bordir Tasikmalaya dalam Konstelasi Estetik dan Identitas”. Penelitian ini mengkaji seni bordir Tasikmalaya dilihat dari aspek estetik dan identitas. Metode yang digunakan adalah metode deskriptif-analitik. Teknik pengumpulan data dalam penelitian ini adalah survei ke lapangan melalui wawancara, pengamatan secara langsung, dan pengambilan sumber-sumber tertulis dari masyarakat dan pemerintah setempat. Sumber data yang digunakan dalam penelitian ini adalah data lapangan melalui participant observation sebagai data primer dan sumber kepustakan sebagai data sekunder. Objek penelitian ini adalah kerajinan bordir di Tasikmalaya. Hasil dari penelitian ini adalah bahwa latar kultural yang mengawali lahir dan berkembangnya kerajinan bordir Tasikmalaya adalah kondisi kultural Tasikmalaya yang identik dengan aspek religi. Perkembangan kerajinan bordir Tasikmalaya telah mengalami perluasan ke arah dimensi pemaknaan, tujuan, hingga pengaruh estetika modern, pada masanya nanti telah berpengaruh pada adanya bauran estetik antara estetika tradisional dan estetika modern.This study entitled "Tasikmalaya Embroidery Art in Estetic Constelation and Identity". This study reviewed Tasikmalaya embroidery art from the aspects of aesthetic and identity. The method used in this research is descriptive-analytic method. Data collection techniques in this study is a survey of the field through interviews, direct observations, and taking written sources from the community and local government.The object of this study is embroidery in Tasikmalaya.The results obtained from this study is that the cultural background that started the birth embroidery cultural conditions of Tasikmalaya is identical with the religious aspect. Tasikmalaya embroidery developments have expanded toward the dimension of meaning, purpose, to the influence of modern aesthetics, in his time later have an effect on their aesthetic mix between traditional aesthetics and modern aesthetics

Undifferentiated connective tissue disease: a seven-center cross-sectional study of 184 patients

The purpose of this study was to characterize the clinical and serological features of a large cohort of patients with antinuclear antibody (ANA) positive undifferentiated connective tissue disease (UCTD). Consecutive patients with UCTD, followed up at the Rheumatology Clinic of the participating centers, were included. Data from these patients were obtained by clinical evaluation and chart review. All patients were diagnosed as having UCTD on basis of the following criteria: positive ANA plus at least one clinical feature of connective tissue disease, but not fulfilling classification criteria for any differentiated connective tissue disease. One hundred eighty-four patients were studied (female patients-94.5%; mean age at time of evaluation-47 years). The most prevalent manifestations were arthralgia (66%), arthritis (32%), Raynaud's phenomenon (30%), sicca symptoms (30%), and leukopenia (19%). The prevalence of ANA was 100%, anti-SSA 20%, anti-dsDNA 14%, and anti-SSB 7%. Patients with anti-dsDNA/anti-Sm, anticentromere/anti-Scl70, or anti-SSA/anti-SSB antibodies more frequently presented a set of manifestations close to systemic lupus erythematosus (SLE), systemic sclerosis, or Sjögren syndrome, respectively. We analyze a large cohort of UCTD. Seventy-two percent of these UCTD patients present lupus-, scleroderma-, or Sjögren-like features but do not fulfill classification criteria and mostly present a mild disease

The fragmentation of protostellar discs: the Hill criterion for spiral arms

We present a new framework to explain the link between cooling and fragmentation in gravitationally unstable protostellar discs. This framework consists of a simple model for the formation of spiral arms, as well as a criterion, based on the Hill radius, to determine if a spiral arm will fragment. This detailed model of fragmentation is based on the results of numerical simulations of marginally stable protostellar discs, including those found in the literature, as well as our new suite of 3-D radiation hydrodynamics simulations of an irradiated, optically-thick protostellar disc surrounding an A star. Our set of simulations probes the transition to fragmentation through a scaling of the physical opacity. This model allows us to directly calculate the critical cooling time of Gammie (2001), with results that are consistent with those found from numerical experiment. We demonstrate how this model can be used to predict fragmentation in irradiated protostellar discs. These numerical simulations, as well as the model that they motivate, provide strong support for the hypothesis that gravitational instability is responsible for creating systems with giant planets on wide orbits.Comment: 11 page, 10 figures, submitted to MNRA

The Case of AB Aurigae's Disk in Polarized Light: Is There Truly a Gap?

Using the NICMOS coronagraph, we have obtained high-contrast 2.0 micron imaging polarimetry and 1.1 micron imaging of the circumstellar disk around AB Aurigae on angular scales of 0.3-3 arcsec (40-550 AU). Unlike previous observations, these data resolve the disk in both total and polarized intensity, allowing accurate measurement of the spatial variation of polarization fraction across the disk. Using these observations we investigate the apparent "gap" in the disk reported by Oppenheimer et al. 2008. In polarized intensity, the NICMOS data closely reproduces the morphology seen by Oppenheimer et al., yet in total intensity we find no evidence for a gap in either our 1.1 or 2.0 micron images. We find instead that region has lower polarization fraction, without a significant decrease in total scattered light, consistent with expectations for back-scattered light on the far side of an inclined disk. Radiative transfer models demonstrate this explanation fits the observations. Geometrical scattering effects are entirely sufficient to explain the observed morphology without any need to invoke a gap or protoplanet at that location.Comment: Accepted to ApJ Letter

The International Deep Planet Survey I. The frequency of wide-orbit massive planets around A-stars

Breakthrough direct detections of planetary companions orbiting A-type stars confirm the existence of massive planets at relatively large separations, but dedicated surveys are required to estimate the frequency of similar planetary systems. To measure the first estimation of the giant exoplanetary systems frequency at large orbital separation around A-stars, we have conducted a deep-imaging survey of young (8-400 Myr), nearby (19-84 pc) A- and F-stars to search for substellar companions in the 10-300 AU range. The sample of 42 stars combines all A-stars observed in previous AO planet search surveys reported in the literature with new AO observations from VLT/NaCo and Gemini/NIRI. It represents an initial subset of the International Deep Planet Survey (IDPS) sample of stars covering M- to B-stars. The data were obtained with diffraction-limited observations in H- and Ks-band combined with angular differential imaging to suppress the speckle noise of the central stars, resulting in typical 5-sigma detection limits in magnitude difference of 12 mag at 1", 14 mag at 2" and 16 mag at 5" which is sufficient to detect massive planets. A detailed statistical analysis of the survey results is performed using Monte Carlo simulations. Considering the planet detections, we estimate the fraction of A-stars having at least one massive planet (3-14 MJup) in the range 5-320 AU to be inside 5.9-18.8% at 68% confidence, assuming a flat distribution for the mass of the planets. By comparison, the brown dwarf (15-75 MJup) frequency for the sample is 2.0-8.9% at 68% confidence in the range 5-320 AU. Assuming power law distributions for the mass and semimajor axis of the planet population, the AO data are consistent with a declining number of massive planets with increasing orbital radius which is distinct from the rising slope inferred from radial velocity (RV) surveys around evolved A-stars.Comment: 20 pages, 10 figures, 7 tables. Accepted for publication in A&

Nonlinear thermoelectric response of quantum dots: renormalized dual fermions out of equilibrium

The thermoelectric transport properties of nanostructured devices continue to attract attention from theorists and experimentalist alike as the spatial confinement allows for a controlled approach to transport properties of correlated matter. Most of the existing work, however, focuses on thermoelectric transport in the linear regime despite the fact that the nonlinear conductance of correlated quantum dots has been studied in some detail throughout the last decade. Here, we review our recent work on the effect of particle-hole asymmetry on the nonlinear transport properties in the vicinity of the strong coupling limit of Kondo-correlated quantum dots and extend the underlying method, a renormalized superperturbation theory on the Keldysh contour, to the thermal conductance in the nonlinear regime. We determine the charge, energy, and heat current through the nanostructure and study the nonlinear transport coefficients, the entropy production, and the fate of the Wiedemann-Franz law in the non-thermal steady-state. Our approach is based on a renormalized perturbation theory in terms of dual fermions around the particle-hole symmetric strong-coupling limit.Comment: chapter contributed to 'New Materials for Thermoelectric Applications: Theory and Experiment' Springer Series: NATO Science for Peace and Security Series - B: Physics and Biophysics, Veljko Zlatic (Editor), Alex Hewson (Editor). ISBN: 978-9400749863 (2012

Beneficial properties of lactic acid bacteria naturally present in dairy production

Consumers are increasingly demanding for natural and beneficial foods, in order to improve their health and well-being. Probiotics play an important role in such demand, and dairy foods are commonly used as vehicles for such bacteria, represented predominantly by lactic acid bacteria. Due to consumers demand, food industry is constantly looking for novel bacterial strains, leading to studies that aims the isolation and characterization of their beneficial features. This study aimed to characterize the naturally occurring lactic acid bacteria obtained from a dairy environment, in order to assess their potential use as probiotics.Preliminary screening and PCR analysis, based on 16S rRNA sequencing, were applied to select and identify 15 LAB strains from the genera Lactobacillus (n = 11), Pediococcus (n = 2) and Weissella (n = 2). All strains showed resistance to low pH and the evaluated bile salt concentrations in vitro. The API ZYM test characterized the enzymatic activity of the strains, and a high β-galactosidase activity was observed in 13 strains. All strains presented resistance to simulated gastric (3 h) and intestinal (4 h) conditions in vitro, the ability to auto- and co-aggregate with indicator microorganisms and a high cell surface hydrophobicity. Most of the strains were positive for map and EFTu beneficial genes. All strains exhibited strong deconjugation of bile salts in vitro and all assimilated lactose.The phenotypes exhibited in vitro and the presence of beneficial genes revealed the beneficial potential of the studied strains, demanding further analyses in a food matrix and in vivo to allow the development of a functional product, with health-related properties

The need of dermatologists, psychiatrists and psychologists joint care in psychodermatology

The mind-skin connection has been studied since the nineteenth century. The last 40 years have set the development of new research areas which allowed the clarifying of how these two dimensions interact. The diseases that involve skin and mind constitute the field of psychodermatology and require that specialists in dermatology, psychiatry and psychology together and integrated take part in it, since skin, nervous system and mind are simultaneously affected. This paper aims to expose how psychodermatoses are currently conceptualized and the need of integration of these three specialties for conveniently treating the patients