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Propagation of transient electromagnetic waves in time-varying media-direct and inverse scattering problems

Wave propagation of transient electromagnetic waves in time-varying media is considered. The medium, which is assumed to be inhomogeneous and dispersive, lacks invariance under time translations. The spatial variation of the medium is assumed to be in the depth coordinate, i.e. it is stratified. The constitutive relations of the medium are a time integral of a generalized susceptibility kernel and

A review of fungus gnats in the tribe exechiini (Diptera, Mycetophilidae) from the J. W. Zetterstedt collection at the museum of zoology in Lund, Sweden

The collections of fungus gnats by Johan Wilhelm Zetterstedt (1785-1874), lodged in the Museum of Zoology in Lund, Sweden, are examined for all species belonging in the tribe Exechiini Edwards. The majority of the material was collected in Fennoscandia, mainly in Sweden, in the first half of the 19(th) century. Altogether 37 species of the tribe Exechiini could be safely identified. Three addition

Standardization of diagnostic PCR for the detection of foodborne pathogens.

In vitro amplification of nucleic acids using the polymerase chain reaction (PCR) has become, since its discovery in the 1980s, a powerful diagnostic tool for the analysis of microbial infections as well as for the analysis of microorganisms in food samples. However, despite its potential, PCR has neither gained wide acceptance in routine diagnostics nor been widely incorporated in standardized me

Single-electron transistors in heterostructure nanowires.

Semiconductor-based single-electron transistors have been fabricated using heterostructure nanowire growth, by introducing a double barrier of InP into InAs nanowires. From electrical measurements, we observe a charging energy of 4 meV for the approximately 55 nm diameter and 100 nm long InAs islands between the InP barriers. The Coulomb blockade can be periodically lifted as a function of gate vo

Symptoms and signs in single and mixed genital infections

OBJECTIVE: To compare symptoms and signs in women with single and mixed genital infections. METHODS: The study population comprised 996 apparently healthy women. Gynecological symptoms and signs were looked for and diagnostics for the most prevalent gynecological infections were made. RESULTS: When co-infections were excluded, chlamydial infections, bacterial vaginosis and cervical human papilloma

High rate reactive dc magnetron sputter deposition of Al2O3 films

Aluminum oxide films were produced by reactive dc magnetron sputtering of Al in Ar+O2. The composition of the films was characterized by Rutherford backscattering measurements. Stoichiometric films possessed excellent optical properties with a refractive index of ∼1.6 for visible and near-infrared light. It was possible to produce stoichiometric films while keeping the target in the metallic mode

Haplotypes of the estrogen receptor beta gene and breast cancer risk

Exposure to exogenous (oral contraceptives, postmenopausal hormone therapy) and endogenous (number of ovulatory cycles, adiposity) steroid hormones is associated with breast cancer risk. Breast cancer risk associated with these exposures could hypothetically be modified by genes in the steroid hormone synthesis, metabolism and signaling pathways. Estrogen receptors are the first step along the pat

Repeated apneas do not affect the hypercapnic ventilatory response in the short term.

Long-term training of breath-hold diving reduces the hypercapnic ventilatory response (HCVR), an index of the CO(2) sensitivity. The aim of the present study was to elucidate whether also short-term apnea training (repeating apneas with short intervals) reduces the HCVR, thereby being one contributing factor explaining the progressively increasing breath-holding time (BHT) with repetition of apnea

Early gastric carcinoma with focal advanced cancer: a particular subtype of gastric carcinoma

Early gastric cancer (EGC) is defined as a carcinoma limited to the mucosa or mucosa and submucosa, irrespective of whether metastasis to lymph nodes has occurred. EGC presents a much more favorable prognosis than advanced gastric carcinoma (AGC), with a 5-year survival rate between 88% and 96% for EGC versus 45% to 50% for AGC. Moreover, some gastric cancers appear as a more or less extended EGC

Recrystallisation behaviour of native and processed waxy maize starch in relation to the molecular characteristics

Molecular characteristics were determined for native waxy maize starch and maize starch modified in different way (by mechanical treatment or/and acid hydrolysis). Recrystallisation behaviour was studied. Methods used in this study were MALLS, HPAEC-PAD, NMR, DSC, SEM, light microscopy. Five starch materials were subjected to storage under the same conditions in the presence of water (70 w/w%). Mo

Effects of temperature, salt, and deuterium oxide on the self-aggregation of alkylglycosides in dilute solution. 2. n-Tetradecyl-beta-D-maltoside

The effects of salt, temperature, and deuterium oxide on the self-aggregation of n-tetradecyl-beta-D-maltoside (C(14)G(2)) in dilute solution have been investigated by static light scattering, dynamic light scattering (DLS), small-angle neutron scattering (SANS), tensiometry, and capillary viscometry. SANS data show that the micelles can be described as relatively flexible polymer-like micelles wi

Occupational airborne allergic contact dermatitis from methacrylates in a dental nurse

Background: There are very few reports of airborne allergic contact dermatitis from methacrylates. Objectives: To report a dental nurse with facial eczema supposedly caused by airborne methacrylates present in the work environment. Methods: Patch testing with serial dilutions of several methacrylates and work provocations in environments containing methacrylates was performed. Results: Patch testi

Modeling serum creatinine in septic ICU patients

Serum creatinine is a metabolite assumed to be constantly produced by the normally functioning muscle mass and is a good measure for monitoring daily renal function in the intensive care unit (ICU). High serum creatinine levels or an abnormal departure from normal pre-disease basal levels are indices of acute renal failure (ARF). Septic ICU patients develop multi-organ failure and ARF is often an

Monitor – Biology

The hottest developments in the fields of cancer research, neuroscience, genomics and proteomics, anti-virals and more, with a pick of the key research papers in these areas.

Physical properties of the sub-micrometer aerosol over the Amazon rain forest during the wet-to-dry season transition - comparison of modeled and measured CCN concentrations

Sub-micrometer atmospheric aerosol particles were studied in the Amazon region, 125 km northeast of Manaus, Brazil (-1degrees55.2'S, 59degrees28.1'W). The measurements were performed during the wet-to-dry transition period, 4-28 July 2001 as part of the LBA (Large-Scale Biosphere Atmosphere Experiment in Amazonia) CLAIRE-2001 (Cooperative LBA Airborne Regional Experiment) experiment. The number si

Ex vivo and in vitro studies of transgene expression in rat astrocytes transduced with lentiviral vectors.

Implantation of cells genetically modified to express therapeutic genes into the brain has been proposed as a potential treatment for neurodegenerative diseases. In the current study embryonic rat-derived astrocytes were cultured and transduced with a lentiviral vector expressing the reporter gene green fluorescent protein (GFP) and subsequently grafted into the adult rat brain. The proportion of

Importance of processing for physico-chemical and physiological properties of dietary fibre.

There is considerable loss of DM during wet heat treatment of vegetables, leading to an increase in dietary fibre. Correction for the loss of DM indicates that the effects on total dietary fibre are minor. There is, however, depolymerization of the dietary fibre polysaccharides. The degradation is related to the severity of the heat treatment. Souring, freezing and mild microwave treatment have no

The CO2 inhibition of terrestrial isoprene emission significantly affects future ozone projections

Simulations of future tropospheric composition often include substantial increases in biogenic isoprene emissions arising from the Arrhenius-like leaf emission response and warmer surface temperatures, and from enhanced vegetation productivity in response to temperature and atmospheric CO2 concentration. However, a number of recent laboratory and field data have suggested a direct inhibition of le