Why disadvantaged neighborhoods are more attractive targetsfor burgling than wealthy ones

Despite concerns about crime among the wealthy and middle-class, crime is much more prevalent in poor inner-city neighborhoods than in better off suburbs. In new research, Alyssa W. Chamberlain and Lyndsay N. Boggess explore why wealthier neighborhoods have lower burglary rates – after all, they are more likely to possess more valuable goods. They find that burglars from poorer areas are more likely to target neighborhoods more disadvantaged than their own. They write that not only are wealthier neighborhoods more likely to be further away, increasing the risks for potential burglars; they are also likely to be more socially connected. More disadvantaged neighborhoods, on the other hand, are more likely to be less socially cohesive, making it easier for burglars to remain anonymous

Practice variation in late-preterm deliveries: a physician survey

Objective: Late preterm (LPT) neonates account for over 70% of all preterm births in the US. Approximately 60% of LPT births are the result of non-spontaneous deliveries.The optimal timing of delivery for many obstetric conditions at LPT gestations is unclear, likely resulting in obstetric practice variation. The purpose of this study is to identify variation in the obstetrical management of LPT pregnancies. Study design: We surveyed obstetrical providers in NC identified from NC Medical Board and NC Obstetrical and Gynecological Society membership lists. Participants answered demographic questions and 6 multiple-choice vignettes on management of LPT pregnancies. Result: We obtained 215/859 (29%) completed surveys; 167 (78%) from Obstetrics/Gynecology, 27 (13%) from Maternal-Fetal Medicine, and 21 (10%) from Family Medicine physicians. Overall, we found more agreement on respondents’ management of chorioamnionitis (97% would proceed with delivery), mild preeclampsia (84% would delay delivery/expectantly manage), and fetal growth restriction (80% would delay delivery/expectantly manage). We found less agreement on the management of severe preeclampsia (71% would proceed with delivery), premature preterm rupture of membranes (69% would proceed with delivery), and placenta previa (67% would delay delivery/expectantly manage). Management of LPT pregnancies complicated by PPROM, FGR, and placenta previa vary by specialty. Conclusion: Obstetrical providers report practice variation in the management of LPT pregnancies. Variation might be influenced by provider specialty. The absence of widespread agreement on best practice might be a source of modifiable LPT birth

Infrared receivers for low background astronomy: Incoherent detectors and coherent devices from one micrometer to one millimeter

The status of incoherent detectors and coherent receivers over the infrared wavelength range from one micrometer to one millimeter is described. General principles of infrared receivers are included, and photon detectors, bolometers, coherent receivers, and important supporting technologies are discussed, with emphasis on their suitability for low background astronomical applications. Broad recommendations are presented and specific opportunities are identified for development of improved devices

Extremal discs and the holomorphic extension from convex hypersurfaces

Let D be a convex domain with smooth boundary in complex space and let f be a continuous function on the boundary of D. Suppose that f holomorphically extends to the extremal discs tangent to a convex subdomain of D. We prove that f holomorphically extends to D. The result partially answers a conjecture by Globevnik and Stout of 1991

Intrinsic Absorption Lines in Seyfert 1 Galaxies. I. Ultraviolet Spectra from the Hubble Space Telescope

We present a study of the intrinsic absorption lines in the ultraviolet spectra of Seyfert 1 galaxies. We find that the fraction of Seyfert 1 galaxies that show absorption associated with their active nuclei is more than one-half (10/17), which is much higher than previous estimates (3 - 10%) . There is a one-to-one correspondence between Seyferts that show intrinsic UV absorption and X-ray ``warm absorbers''. The intrinsic UV absorption is generally characterized by high ionization: C IV and N V are seen in all 10 Seyferts with detected absorption (in addition to Ly-alpha), whereas Si IV is present in only four of these Seyferts, and Mg II absorption is only detected in NGC 4151. The absorption lines are blueshifted (or in a few cases at rest) with respect to the narrow emission lines, indicating that the absorbing gas is undergoing net radial outflow. At high resolution, the absorption often splits into distinct kinematic components that show a wide range in widths (20 - 400 km/s FWHM), indicating macroscopic motions (e.g., radial velocity subcomponents or turbulence) within a component. The strong absorption components have cores that are much deeper than the continuum flux levels, indicating that the regions responsible for these components lie completely outside of the broad emission-line regions. The covering factor of the absorbing gas in the line of sight, relative to the total underlying emission, is C > 0.86, on average. The global covering factor, which is the fraction of emission intercepted by the absorber averaged over all lines of sight, is C > 0.5.Comment: 56 pages, Latex, includes 4 figures (encapsulated postscript), Fig. 1 has 2 parts and Fig. 2 has 3 parts, to appear in the Astrophysical Journa

Spin relaxation in (110) and (001) InAs/GaSb superlattices

We report an enhancement of the electron spin relaxation time (T1) in a (110) InAs/GaSb superlattice by more than an order of magnitude (25 times) relative to the corresponding (001) structure. The spin dynamics were measured using polarization sensitive pump probe techniques and a mid-infrared, subpicosecond PPLN OPO. Longer T1 times in (110) superlattices are attributed to the suppression of the native interface asymmetry and bulk inversion asymmetry contributions to the precessional D'yakonov Perel spin relaxation process. Calculations using a nonperturbative 14-band nanostructure model give good agreement with experiment and indicate that possible structural inversion asymmetry contributions to T1 associated with compositional mixing at the superlattice interfaces may limit the observed spin lifetime in (110) superlattices. Our findings have implications for potential spintronics applications using InAs/GaSb heterostructures.Comment: 4 pages, 2 figure

Nitrofurantoin-induced pulmonary fibrosis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Nitrofurantoin is a commonly used drug in the treatment and prevention of urinary tract infections. Many adverse effects of nitrofurantoin have been documented, including aplastic anemia, polyneuritis, and liver and pulmonary toxicity.</p> <p>Case presentation</p> <p>We describe the clinical history and the autopsy findings in a 51-year-old woman with lung fibrosis of unknown etiology. She had a history of recurrent urinary tract infections, treated with nitrofurantoin for many years. She was referred to our hospital for screening for lung transplantation because of severe pulmonary restriction and dyspnea. Unfortunately, she died as a result of progressive respiratory insufficiency. At autopsy bilateral patchy, sharply circumscribed fibrotic areas in the upper and lower lobes of the lungs were seen with honeycombing. Microscopically, end-stage interstitial fibrosis with diffuse alveolar damage was observed. Due to the atypical distribution of the fibrosis involving both the lower and upper lobes of the lung, the microscopic pattern of the fibrosis and the history of long-term nitrofurantoin use, we concluded that this drug induced the lung fibrosis. The recurrent urinary tract infections were probably caused by a diverticulum of the urinary bladder, which was discovered at autopsy.</p> <p>Conclusion</p> <p>This case shows that the use of nitrofurantoin may cause severe pulmonary disease. Patients with long-term use of nitrofurantoin should be monitored regularly for adverse pulmonary effects.</p

Sub-millimeter to centimeter excess emission from the Magellanic Clouds. I. Global spectral energy distribution

In order to reconstruct the global SEDs of the Magellanic Clouds over eight decades in spectral range, we combined literature flux densities representing the entire LMC and SMC respectively, and complemented these with maps extracted from the WMAP and COBE databases covering the missing the 23--90 GHz (13--3.2 mm) and the poorly sampled 1.25--250 THz (240--1.25 micron). We have discovered a pronounced excess of emission from both Magellanic Clouds, but especially the SMC, at millimeter and sub-millimeter wavelengths. We also determined accurate thermal radio fluxes and very low global extinctions for both LMC and SMC. Possible explanations are briefly considered but as long as the nature of the excess emission is unknown, the total dust masses and gas-to-dust ratios of the Magellanic Clouds cannot reliably be determined.Comment: Accepted for publication by A&

Spin relaxation of conduction electrons in bulk III-V semiconductors

Spin relaxation time of conduction electrons through the Elliot-Yafet, D'yakonov-Perel and Bir-Aronov-Pikus mechanisms is calculated theoretically for bulk GaAs, GaSb, InAs and InSb of both $n$- and $p$-type. Relative importance of each spin relaxation mechanism is compared and the diagrams showing the dominant mechanism are constructed as a function of temperature and impurity concentrations. Our approach is based upon theoretical calculation of the momentum relaxation rate and allows understanding of the interplay between various factors affecting the spin relaxation over a broad range of temperature and impurity concentration.Comment: an error in earlier version correcte

Convection, Thermal Bifurcation, and the Colors of A stars

Broad-band ultraviolet photometry from the TD-1 satellite and low dispersion spectra from the short wavelength camera of IUE have been used to investigate a long-standing proposal of Bohm-Vitense that the normal main sequence A- and early-F stars may divide into two different temperature sequences: (1) a high temperature branch (and plateau) comprised of slowly rotating convective stars, and (2) a low temperature branch populated by rapidly rotating radiative stars. We find no evidence from either dataset to support such a claim, or to confirm the existence of an "A-star gap" in the B-V color range 0.22 <= B-V <= 0.28 due to the sudden onset of convection. We do observe, nonetheless, a large scatter in the 1800--2000 A colors of the A-F stars, which amounts to ~0.65 mags at a given B-V color index. The scatter is not caused by interstellar or circumstellar reddening. A convincing case can also be made against binarity and intrinsic variability due to pulsations of delta Sct origin. We find no correlation with established chromospheric and coronal proxies of convection, and thus no demonstrable link to the possible onset of convection among the A-F stars. The scatter is not instrumental. Approximately 0.4 mags of the scatter is shown to arise from individual differences in surface gravity as well as a moderate spread (factor of ~3) in heavy metal abundance and UV line blanketing. A dispersion of ~0.25 mags remains, which has no clear and obvious explanation. The most likely cause, we believe, is a residual imprecision in our correction for the spread in metal abundances. However, the existing data do not rule out possible contributions from intrinsic stellar variability or from differential UV line blanketing effects owing to a dispersion in microturbulent velocity.Comment: 40 pages, 14 figures, 1 table, AAS LaTex, to appear in The Astrophysical Journa