244 research outputs found

    The Position of High Frequency Waves with Respect to the Granulation Pattern

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    High frequency velocity oscillations were observed in the spectral lines Fe I 543.45nm and 543.29nm, using 2D spectroscopy with a Fabry- Perot and speckle reconstruction, at the VTT in Tenerife. We investigate the radial component of waves with frequencies in the range 8 - 22mHz in the internetwork, network and a pore. We find that the occurrence of waves do not show any preference on location and are equally distributed over down-flows and up-flows, regardless of the activity of the observed area in the line of Fe I 543.45nm. The waves observed in the lower formed line of Fe I 543.29nm seem to appear preferentially over down-flows.Comment: Article has 12 pages and 7 images. It is accepted in Solar Physics Journa

    Phased-array wavelength demultiplexer with flattened wavelength response

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    A four-channel phased-array wavelength demultiplexer with a flattened wavelength response has been realised for the first time in InP/InGaAsP at 1.54 mu m by employing multimode output waveguides. The device has 2 nm channel spacing and a flat response (within 1 dB) of 17 n

    Chemopreventive targeted treatment of head and neck precancer by Wee1 inhibition

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    HPV-negative head and neck squamous cell carcinomas (HNSCCs) develop in precancerous changes in the mucosal lining of the upper-aerodigestive tract. These precancerous cells contain cancer-associated genomic changes and cause primary tumors and local relapses. Therapeutic strategies to eradicate these precancerous cells are very limited. Using functional genomic screens, we identified the therapeutic vulnerabilities of premalignant mucosal cells, which are shared with fully malignant HNSCC cells. We screened 319 previously identified tumor-lethal siRNAs on a panel of cancer and precancerous cell lines as well as primary fibroblasts. In total we identified 147 tumor-essential genes including 34 druggable candidates. Of these 34, 13 were also essential in premalignant cells. We investigated the variable molecular basis of the vulnerabilities in tumor and premalignant cell lines and found indications of collateral lethality. Wee1-like kinase (WEE1) was amongst the most promising targets for both tumor and precancerous cells. All four precancerous cell lines were highly sensitive to Wee1 inhibition by Adavosertib (AZD1775), while primary keratinocytes tolerated this inhibitor. Wee1 inhibition caused induction of DNA damage during S-phase followed by mitotic failure in (pre)cancer cells. In conclusion, we uncovered Wee1 inhibition as a promising chemopreventive strategy for precancerous cells, with comparable responses as fully transformed HNSCC cells

    Screening and time trend study of decabromodiphenylether in birds

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    In 2001, Swedish scientists reported the presence of decabromodiphenylether (DBDE) in peregrine falcons. Subsequently, we have carried out an extensive study on the presence and time trends of DBDE in predatory birds and water birds in order to provide information on this subject for the European environmental risk assessment of DBDE. The UK Environment Agency and the Bromine Science and Environmental Forum (BSEF) initiated the study

    Micromachined pipettes integrated in a flow channel for single DNA molecule study by optical trapping

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    We have developed a micromachined flow cell consisting of a flow channel integrated with micropipettes. The flow cell is used in combination with an optical trap set-up (optical tweezers) to study mechanical and structural properties of λ-DNA molecules. The flow cell was realized using silicon micromachining including the so-called buried channel technology to fabricate the micropipettes, the wet etching of glass to create the flow channel, and the powder blasting of glass to create the fluid connections. The volume of the flow cell is 2 µl. The pipettes have a length of 130 µm, a width of 5-10 µm, a round opening of 1 micron and can be processed with different shapes. Using this flow cell we stretched single molecules (λ-DNA) showing typical force-extension curves also found with conventional techniques

    Surgical treatment for squamous cell carcinoma of the temporal bone: predictors of survival

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    Objective. Evaluation of the management and survival in patients treated for temporal bone squamous cell carcinoma (TBSCC) in a tertiary referral centre.Methods. Forty-nine patients underwent primary treatment for TBSCC. Thirty-six patients underwent a lateral temporal bone resection (LTBR) or subtotal temporal bone resection (STBR). Overall survival (OS) and disease-specific survival (DSS) analysis were assessed.Results. Five-year OS of the 49 patients was 39%. Five-year OS of the 36 patients who underwent LTBR or STBR was 46%. Tumour-free margins were achieved in all patients with T1 and T2 disease, in 59% patients with T3 tumours and 0% patients with T4 disease. Fiveyear DSS was 85% for all T1/T2 tumours, 53% for T3 tumours and 0% for T4 tumours. Clear resection margins was the only significant predictor of DSS in our cohort.Conclusions. The mainstay of treatment for TBSCC is temporal bone resection with tumour free resection margins, with or without adjuvant radiotherapy. Survival is negatively influenced by non-radical resection. T1 and T2 tumours can be managed safely with LTBR. More advanced disease requires a more extensive resection, with a higher likelihood of nonradical resections and decreased survival rates.Otorhinolaryngolog
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