Optical third harmonic generation in the magnetic semiconductor EuSe

Third harmonic generation (THG) has been studied in europium selenide EuSe in the vicinity of the band gap at 2.1-2.6 eV and at higher energies up to 3.7 eV. EuSe is amagnetic semiconductor crystalizing in centrosymmetric structure of rock-salt type with the point group m3m. For this symmetry the crystallographic and magnetic-field-induced THG nonlinearities are allowed in the electric-dipole approximation. Using temperature, magnetic field, and rotational anisotropy measurements, the crystallographic and magnetic-field-induced contributions to THG were unambiguously separated. Strong resonant magnetic-field-induced THG signals were measured at energies in the range of 2.1-2.6 eV and 3.1-3.6 eV for which we assign to transitions from 4 f(7) to 4 f(6)5d(1) bands, namely involving 5d(t(2g)) and 5d(e(g)) states.

GPR applied to mapping utilities along the route of the Line 4 (yellow) subway tunnel construction in Sao Paulo City, Brazil

The rapid industrial development and disorganized population growth in huge cities bring about various urban problems due to intense use of physical space on and below the surface. Subsurface problems in metropolitan areas are caused by subway line construction, which often follows the routes of utility networks, such as electric and telephone cables, water and gas pipes, storm sewers, etc. Usually, the main problems are related to damage or destruction of preexisting utilities, often putting human lives at risk. With the purpose of minimizing risks. GPR-profiling with 200 MHz antennae was done at two sites, both located in downtown Sao Paulo, Brazil. The objectives of this work were to map utilities or existing infrastructure in the subsurface in order to orient the construction of the Line 4 (yellow) subway tunnel in Sao Paulo. GPR profiles can detect water pipes, utility networks in the subsurface, and concrete foundation columns or pilings in subsoil up to 2 m depth. In addition. the GPR profiles also provided details of the target shapes in the subsurface. GPR interpretations combined with lithological information from boreholes and trenches opened in the study areas were extremely important in mapping of the correct spatial distribution of buried utilities at these two sites in Sao Paulo. This information improves and updates maps of utility placement, serves as a basis for planning of the geotechnical excavation of the Line 4 (yellow) subway tunnel in Sao Paulo, helps minimize problems related to destruction of preexisting utilities in the subsoil, and avoids risk of dangerous accidents. (C) 2012 Elsevier B.V. All rights reserved.

Tunnel excavation triggering pulmonary sarcoidosis

Context A definite cause of sarcoidosis has not been identified, however past research suggests that environmental factors may be triggers of the granulomatous response in genetically susceptible individuals. Case Presentation A 22-year-old male non-smoker, presented with progressive exertional dyspnea and cough of 3 months duration. One year before, when he started working in tunnel excavation, he had a normal chest radiograph. Chest imaging revealed bilateral nodules and masses of peribronchovascular distribution plus mediastinal lymphadenomegaly. Histologic lymph node analysis revealed non-caseating confluent granulomas. Sarcoidosis was diagnosed. The patient was treated with corticosteroids and advised to change jobs. Complete remission of the disease was achieved and persisted for at least one year without steroid treatment. Discussion Sarcoidosis is believed to have environmental triggers. The timing of the onset of sarcoidosis in this patient following intensive exposure to tunnel dust suggests an environmental contribution. The recognition that sarcoidosis may have occupational triggers have medical, employment, and legal implications. Am. J. Ind. Med. 55: 390-394, 2012. (C) 2011 Wiley Periodicals, Inc.

Effectiveness of low-level laser therapy for patients with carpal tunnel syndrome: design of a randomized single-blinded controlled trial

Background: Carpal tunnel syndrome is the most common neuropathy in the upper extremity, resulting from the compression of the median nerve at wrist level. Clinical studies are essentials to present evidence on therapeutic resources use at early restoration on peripheral nerve functionality. Low-level laser therapy has been widely investigated in researches related to nerve regeneration. Therefore, it is suggested that the effect of low-level laser therapy associated with other conservative rehabilitation techniques may positively affect symptoms and overall hand function in compressive neuropathies such as carpal tunnel syndrome. The aim of this study is to evaluate the effectiveness of low-level laser therapy in addition to orthoses therapy and home orientations in patients with carpal tunnel syndrome. Methods/Design: Patients older than 18 years old will be included, with clinical diagnosis of carpal tunnel syndrome, excluding comorbidies. A physiotherapist will conduct intervention, with a blinding evaluator. Randomization will be applied to allocate the patients in each group: with association or not to low-level laser therapy. All of them will be submitted to orthoses therapy and home orientations. Outcome will be assessed through: pain visual analogic scale, Semmes Weinstein monofilaments (TM) threshold sensibility test, Pinch Gauge T, Boston Carpal Tunnel Questionnaire and two point discrimination test. Discussion: This paper describes the design of a randomized controlled trial, which aim to assess the effectiveness of conservative treatment added to low-level laser therapy for patients with carpal tunnel syndrome. Trial registration: Brazilian Clinical Trials Registry (ReBec) - 75ddtf / Universal Trial Number: U1111-1121-5184

Temperature impact on the tunnel fet off-state current components

In this work, the temperature impact on the off-state current components is analyzed through numerical simulation and experimentally. First of all, the band-to-band tunneling is studied by varying the underlap in the channel/drain junction, leading to an analysis of the different off-state current components. For pTFET devices, the best behavior for off-state current was obtained for higher values of underlap (reduced BTBT) and at low temperatures (reduced SRH and TAT). At high temperature, an unexpected off-state current occurred due to the thermal leakage current through the drain/channel junction. Besides, these devices presented a good performance when considering the drain current as a function of the drain voltage, making them suitable for analog applications. (C) 2012 Elsevier Ltd. All rights reserved.