Fluctuations of the local density of states probe localized surface plasmons on disordered metal films

We measure the statistical distribution of the local density of optical states (LDOS) on disordered semi-continuous metal films. We show that LDOS fluctuations exhibit a maximum in a regime where fractal clusters dominate the film surface. These large fluctuations are a signature of surface-plasmon localization on the nanometer scale

The missing intrauterine device

The Intrauterine Contraceptive Device (IUD) is an acceptable and common form of contraception worldwide. The objective of this study was to report the case of an asymptomatic missing intrauterine contraceptive (IUD) inserted to prevent intrauterine adhesions after synechiolysis. A patient presented with missing IUD threads. Ultrasound of the pelvis showed an empty uterine cavity with the missing IUD probably anterior to the uterus. We present a stepwise approach in the management of the “lost IUD”, where the strings of the device are not visible at the time of speculum examination. We suggest first determining sonographically whether the IUD is within the cavity. If it is in situ, options for retrieval are including hysteroscopic retrieval. If the IUD is not within the cavity, X-rays are recommended. The device will not be present on X-ray if expulsion has occurred. If the device is present on the X-ray, cystoscopic or laparoscopic retrieval is required. IUD-providers should not only screen potential users and insert IUD correctly, but also ensure adequate follow-up with localization

A high-wavenumber boundary-element method for an acoustic scattering problem

In this paper we show stability and convergence for a novel Galerkin boundary element method approach to the impedance boundary value problem for the Helmholtz equation in a half-plane with piecewise constant boundary data. This problem models, for example, outdoor sound propagation over inhomogeneous flat terrain. To achieve a good approximation with a relatively low number of degrees of freedom we employ a graded mesh with smaller elements adjacent to discontinuities in impedance, and a special set of basis functions for the Galerkin method so that, on each element, the approximation space consists of polynomials (of degree $\nu$) multiplied by traces of plane waves on the boundary. In the case where the impedance is constant outside an interval $[a,b]$, which only requires the discretization of $[a,b]$, we show theoretically and experimentally that the $L_2$ error in computing the acoustic field on $[a,b]$ is ${\cal O}(\log^{\nu+3/2}|k(b-a)| M^{-(\nu+1)})$, where $M$ is the number of degrees of freedom and $k$ is the wavenumber. This indicates that the proposed method is especially commendable for large intervals or a high wavenumber. In a final section we sketch how the same methodology extends to more general scattering problems

Metabolism of materials by the construction sector in developing countries : Costa Rica as a case study

Production practices require large amounts of materials and are not likely to be sustained without large implication for the environment. Materials and energy are put together in order to produce goods and the total of these physical processes have been referred by Ayres and Simons as "Industrial Metabolism", which was defined as "the whole integrated collection of physical processes that convert raw materials, plus labour, into finished products and wastes in a (more or less) steady-state condition". A good understanding of societal metabolism is likely to contribute to more sustainable production and consumption. The construction industry and its related materials, service, and supply feeder industries are jointly considered to be both the world's largest industrial employer and the largest natural resources consumer as well as a great waste producer. In developing countries, construction waste is becoming a serious environmental problem due to the continuing growing population and urbanization, which demand material resources, water and energy. Information and data about the sector in those economies is scarce and some of the information found can't be compared with other data. An assessment has been done in Costa Rica in order to understand how construction materials are metabolised (transformed) by the sector. The study provides an idea of the amount of waste generation and its composition. It also shows the causes, which are related to design, procurement, material handling, operation, residual and others

Laparoscopic Sacropexy: A Retrospective Analysis of the Subjective Outcome in 310 Cases

Background and Objective. The aim of this study was to assess the subjective outcome following laparoscopic sacropexy. Methods. We performed a retrospective cohort study among women treated for descensus with laparoscopic sacropexy between January 2000 and December 2007. 310 patients received questionnaires during followup assessing major pre- and postoperative symptoms and overall satisfaction. Results. 214 (69%) patients responded to the questionnaire. Mean followup was 24.5 months. The number of patients with back or lower abdominal pain, foreign body sensation in the vagina and prolapse-related symptoms, urinary symptoms, vaginal and bladder infections, and the need for pessary usage decreased significantly postsurgically. Bowel symptoms increased slightly but not significantly. Two years after surgery, nearly 2 thirds of the women were satisfied or very satisfied with the outcome. Conclusion. Laparoscopic sacropexy is an effective treatment of descensus, with favorable or satisfactory subjective outcomes

Search for Magnetic Field Induced Gap in a High-Tc Superconductor

Break junctions made of the optimally doped high temperature superconductor Bi2Sr2Ca2CuO8 with Tc of 90 K has been investigated in magnetic fields up to 12 T, at temperatures from 4.2 K to Tc. The junction resistance varied between 1kOhm and 300kOhm. The differential conductance at low biases did not exhibit a significant magnetic field dependence, indicating that a magnetic-field-induced gap (Krishana et al., Science 277 83 (1997)), if exists, must be smaller than 0.25 meV.Comment: 3 pages, 2 figure