Fiber-optic current sensor with self-compensation of source wavelength changes.

We demonstrate a method for self-compensation of scale factor changes of an interferometric fiber-optic current sensor caused by source wavelength shifts, e.g., due to changes in source temperature or drive current. An adequately tailored fiber-optic retarder in the optical circuit introduces wavelength-dependent mixing of the orthogonal polarization modes of the sensor. The resulting change in scale factor balances the variation of the Faraday effect with wavelength. The wavelength dependence of the sensor is suppressed by more than an order of magnitude to <0.2% over wavelength spans of at least 10 nm around 1305 nm. The retarder is designed as an athermal device for operation between -40°C and 80°C.

Observation of few-cycle, strong-field phenomena in surface plasmon fields.

We present experimental evidence of the generation of few-cycle propagating surface plasmon polariton wavepackets. These ultrashort plasmonic pulses comprised of only 2-3 field oscillations were characterized by an autocorrelation measurement based on electron photoemission. By exploiting plasmonic field enhancement, we achieved plasmon-induced tunnelling emission from the metal surface at low laser intensity, opening perspectives for strong-field experiments with low pulse energies. All-optical electron acceleration up to keV kinetic energy is also demonstrated in these surface-confined, few-cycle fields with only 1.35×10(12) W/cm2 focused laser intensity. The experimental results are found to be in excellent agreement with the model.

CHEK2 is a multiorgan cancer susceptibility gene.

A single founder allele of the CHEK2 gene has been associated with predisposition to breast and prostate cancer in North America and Europe. The CHEK2 protein participates in the DNA damage response in many cell types and is therefore a good candidate for a multisite cancer susceptibility gene. Three founder alleles are present in Poland. Two of these result in a truncated CHEK2 protein, and the other is a missense substitution of an isoleucine for a threonine. We ascertained the prevalence of each of these alleles in 4,008 cancer cases and 4,000 controls, all from Poland. The majority of the common cancer sites were represented. Positive associations with protein-truncating alleles were seen for cancers of the thyroid (odds ratio [OR] 4.9; P=.0006), breast (OR 2.2; P=.02), and prostate (OR 2.2; P=.04). The missense variant I157T was associated with an increased risk of breast cancer (OR 1.4; P=.02), colon cancer (OR 2.0; P=.001), kidney cancer (OR 2.1; P=.0006), prostate cancer (OR 1.7; P=.002), and thyroid cancer (OR 1.9; P=.04). The range of cancers associated with mutations of the CHEK2 gene may be much greater than previously thought.

[Identification of Helicobacter pylori and associated gastric lesions]. / Identificación de Helicobacter pylori y lesiones gástricas asociadas.

In this study is presented a silver stain technique for Helicobacter pylori with ammoniacal silver carbonato of Del Río Hortega, in biopsies and surgical specimens embebbed in paraffine. This study was performed between 1999 to 2001, and 717 gastroscopics biopsies were observed, that included: 705 chronic gastritis (98.32%), 11 gastric carcinomas (1.53%), and 1 low-grade lymphoma (0.13%). It is important to note the low incidence of adenocarcinomas and lymphomas from 717 gastroscopic biopsies during the period of 1999-2001, only 11 carcinomas and 1 lymphoma. We added 28 retrospective studies of biopsies and surgical specimens. These latter group included 21 adenocarcinomas and 7 low-grade lymphomas. Hence, there were a total of 745 cases with: 705 chronic gastritis, 32 adenocarcinomas, and 8 low-grade lymphomas. In 705 chronic gastritis, 325 (46.10%) were associated with H pylori, and they were Chronic Superficial Gastritis of Mild (8.62%), Moderate (61.23%), and Severe (12.92%) intensity; and Follicular Gastritis in 17.23%. In a serie of 82 total Follicular Gastritis (82/705), H pylori was founded in 68.29% (56/82). This relative frequency of association between H pylori with Chronic Gastritis in general (46.10%), and with Follicular Gastritis in particular (68.29%), could be explain because: a--many gastroscopic biopsies did not became from antrum, site of H pylori growing. Or b--there was another etiologic factor without morphologic value. There is a clear evidence that H pylori is an important factor in the pathogenesis of these chronic gastritis, from primary Acute Gastritis occurred in children and young patients, to Chronic Superficial Gastritis, Follicular Gastritis, Atrophic Gastritis, intestinal metaplasia, and Peptic Ulcer present in adult patients. Adenocarcinomas were associated with moderate and severe Chronic Superficial Gastritis, Atrophic Gastritis, intestinal metaplasia, and moderate and severe dysplasias of glandular epithelium. H pylori was founded in only 35% of adenocarcinomas, probably related to the presence of atrophic gastritis associated with metaplastic/dysplastic changes, or necrotic tissues, which would possibly explain the absent of H pylori growing under these circumstances. Low-grade lymphomas (MALT-type), arise from lymphatic tissue of the mucosa, and were associated with chronic gastritis, atrophy, and intestinal metaplasia. H pylori was founded in 75% of all lymphomas. Also in this case, there is a clear pathogenic evidence between H pylori infection and the development of low-grade lymphoma, specially in early stages, since it is possible the complete resolution after antibiotic therapy or partial gastrectomy.

Identificación de Helicobacter pylori y lesiones gástricas asociadas. / [Identification of Helicobacter pylori and associated gastric lesions]

In this study is presented a silver stain technique for Helicobacter pylori with ammoniacal silver carbonato of Del Río Hortega, in biopsies and surgical specimens embebbed in paraffine. This study was performed between 1999 to 2001, and 717 gastroscopics biopsies were observed, that included: 705 chronic gastritis (98.32

), 11 gastric carcinomas (1.53

), and 1 low-grade lymphoma (0.13

). It is important to note the low incidence of adenocarcinomas and lymphomas from 717 gastroscopic biopsies during the period of 1999-2001, only 11 carcinomas and 1 lymphoma. We added 28 retrospective studies of biopsies and surgical specimens. These latter group included 21 adenocarcinomas and 7 low-grade lymphomas. Hence, there were a total of 745 cases with: 705 chronic gastritis, 32 adenocarcinomas, and 8 low-grade lymphomas. In 705 chronic gastritis, 325 (46.10

) were associated with H pylori, and they were Chronic Superficial Gastritis of Mild (8.62

), Moderate (61.23

), and Severe (12.92

) intensity; and Follicular Gastritis in 17.23

. In a serie of 82 total Follicular Gastritis (82/705), H pylori was founded in 68.29

(56/82). This relative frequency of association between H pylori with Chronic Gastritis in general (46.10

), and with Follicular Gastritis in particular (68.29

), could be explain because: a--many gastroscopic biopsies did not became from antrum, site of H pylori growing. Or b--there was another etiologic factor without morphologic value. There is a clear evidence that H pylori is an important factor in the pathogenesis of these chronic gastritis, from primary Acute Gastritis occurred in children and young patients, to Chronic Superficial Gastritis, Follicular Gastritis, Atrophic Gastritis, intestinal metaplasia, and Peptic Ulcer present in adult patients. Adenocarcinomas were associated with moderate and severe Chronic Superficial Gastritis, Atrophic Gastritis, intestinal metaplasia, and moderate and severe dysplasias of glandular epithelium. H pylori was founded in only 35

of adenocarcinomas, probably related to the presence of atrophic gastritis associated with metaplastic/dysplastic changes, or necrotic tissues, which would possibly explain the absent of H pylori growing under these circumstances. Low-grade lymphomas (MALT-type), arise from lymphatic tissue of the mucosa, and were associated with chronic gastritis, atrophy, and intestinal metaplasia. H pylori was founded in 75

of all lymphomas. Also in this case, there is a clear pathogenic evidence between H pylori infection and the development of low-grade lymphoma, specially in early stages, since it is possible the complete resolution after antibiotic therapy or partial gastrectomy.

Estimation of trends in urban traffic NOx emissions by an empirical model

A model has been developed to estimate trends in urban traffic NOx emissions by measured NO2 concentrations.