557 research outputs found

    PANIC: the new panoramic NIR camera for Calar Alto

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    PANIC is a wide-field NIR camera, which is currently under development for the Calar Alto observatory (CAHA) in Spain. It uses a mosaic of four Hawaii-2RG detectors and covers the spectral range from 0.8-2.5 micron(z to K-band). The field-of-view is 30x30 arcmin. This instrument can be used at the 2.2m telescope (0.45arcsec/pixel, 0.5x0.5 degree FOV) and at the 3.5m telescope (0.23arcsec/pixel, 0.25x0.25 degree FOV). The operating temperature is about 77K, achieved by liquid Nitrogen cooling. The cryogenic optics has three flat folding mirrors with diameters up to 282 mm and nine lenses with diameters between 130 mm and 255 mm. A compact filter unit can carry up to 19 filters distributed over four filter wheels. Narrow band (1%) filters can be used. The instrument has a diameter of 1.1 m and it is about 1 m long. The weight limit of 400 kg at the 2.2m telescope requires a light-weight cryostat design. The aluminium vacuum vessel and radiation shield have wall thicknesses of only 6 mm and 3 mm respectively.Comment: This paper has been presented in the SPIE of Astronomical Telescopes and Instrumentation 2008 in Marseille (France

    Characterizing Exoplanets in the Visible and Infrared: A Spectrometer Concept for the EChO Space Mission

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    Transit-spectroscopy of exoplanets is one of the key observational techniques to characterize the extrasolar planet and its atmosphere. The observational challenges of these measurements require dedicated instrumentation and only the space environment allows an undisturbed access to earth-like atmospheric features such as water or carbon-dioxide. Therefore, several exoplanet-specific space missions are currently being studied. One of them is EChO, the Exoplanet Characterization Observatory, which is part of ESA's Cosmic Vision 2015-2025 program, and which is one of four candidates for the M3 launch slot in 2024. In this paper we present the results of our assessment study of the EChO spectrometer, the only science instrument onboard this spacecraft. The instrument is a multi-channel all-reflective dispersive spectrometer, covering the wavelength range from 400 nm to 16 microns simultaneously with a moderately low spectral resolution. We illustrate how the key technical challenge of the EChO mission - the high photometric stability - influences the choice of spectrometer concept and drives fundamentally the instrument design. First performance evaluations underline the fitness of the elaborated design solution for the needs of the EChO mission.Comment: 20 pages, 8 figures, accepted for publication in the Journal of Astronomical Instrumentatio

    GRAVITY: getting to the event horizon of Sgr A*

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    We present the second-generation VLTI instrument GRAVITY, which currently is in the preliminary design phase. GRAVITY is specifically designed to observe highly relativistic motions of matter close to the event horizon of Sgr A*, the massive black hole at center of the Milky Way. We have identified the key design features needed to achieve this goal and present the resulting instrument concept. It includes an integrated optics, 4-telescope, dual feed beam combiner operated in a cryogenic vessel; near infrared wavefront sensing adaptive optics; fringe tracking on secondary sources within the field of view of the VLTI and a novel metrology concept. Simulations show that the planned design matches the scientific needs; in particular that 10 microarcsecond astrometry is feasible for a source with a magnitude of K=15 like Sgr A*, given the availability of suitable phase reference sources.Comment: 13 pages, 11 figures, to appear in the conference proceedings of SPIE Astronomical Instrumentation, 23-28 June 2008, Marseille, Franc

    Aptamer-based multiplexed proteomic technology for biomarker discovery

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    Interrogation of the human proteome in a highly multiplexed and efficient manner remains a coveted and challenging goal in biology. We present a new aptamer-based proteomic technology for biomarker discovery capable of simultaneously measuring thousands of proteins from small sample volumes (15 [mu]L of serum or plasma). Our current assay allows us to measure ~800 proteins with very low limits of detection (1 pM average), 7 logs of overall dynamic range, and 5% average coefficient of variation. This technology is enabled by a new generation of aptamers that contain chemically modified nucleotides, which greatly expand the physicochemical diversity of the large randomized nucleic acid libraries from which the aptamers are selected. Proteins in complex matrices such as plasma are measured with a process that transforms a signature of protein concentrations into a corresponding DNA aptamer concentration signature, which is then quantified with a DNA microarray. In essence, our assay takes advantage of the dual nature of aptamers as both folded binding entities with defined shapes and unique sequences recognizable by specific hybridization probes. To demonstrate the utility of our proteomics biomarker discovery technology, we applied it to a clinical study of chronic kidney disease (CKD). We identified two well known CKD biomarkers as well as an additional 58 potential CKD biomarkers. These results demonstrate the potential utility of our technology to discover unique protein signatures characteristic of various disease states. More generally, we describe a versatile and powerful tool that allows large-scale comparison of proteome profiles among discrete populations. This unbiased and highly multiplexed search engine will enable the discovery of novel biomarkers in a manner that is unencumbered by our incomplete knowledge of biology, thereby helping to advance the next generation of evidence-based medicine

    Applying the Maternal Near Miss Approach for the Evaluation of Quality of Obstetric Care: A Worked Example from a Multicenter Surveillance Study

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    Objective. To assess quality of care of women with severe maternal morbidity and to identify associated factors. Method. This is a national multicenter cross-sectional study performing surveillance for severe maternal morbidity, using the World Health Organization criteria. the expected number of maternal deaths was calculated with the maternal severity index (MSI) based on the severity of complication, and the standardized mortality ratio (SMR) for each center was estimated. Analyses on the adequacy of care were performed. Results. 17 hospitals were classified as providing adequate and 10 as nonadequate care. Besides almost twofold increase in maternal mortality ratio, the main factors associated with nonadequate performance were geographic difficulty in accessing health services (P < 0.001), delays related to quality of medical care (P = 0.012), absence of blood derivatives (P = 0.013), difficulties of communication between health services (P = 0.004), and any delay during the whole process (P = 0.039). Conclusions. This is an example of how evaluation of the performance of health services is possible, using a benchmarking tool specific to Obstetrics. in this study the MSI was a useful tool for identifying differences in maternal mortality ratios and factors associated with nonadequate performance of care.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ Campinas UNICAMP, Sch Med Sci, Dept Obstet & Gynaecol, BR-13083881 Campinas, SP, BrazilCtr Res Reprod Hlth Campinas Cemicamp, BR-13083888 Campinas, SP, BrazilUniv Fed Amazonas, Manaus, Amazonas, BrazilSch Med Sci, CISAM, Recife, PE, BrazilUniv Fed Ceara, Fortaleza, Ceara, BrazilUniv Fed Bahia, Salvador, BA, BrazilHosp Geral Cesar Cals, Fortaleza, Ceara, BrazilHosp Geral Fortaleza, Fortaleza, Ceara, BrazilMaternidade Odete Valadares, Belo Horizonte, MG, BrazilHosp Materno Infantil, Goiania, Go, BrazilInst Materno Infantil Pernambuco, Recife, PE, BrazilUniv Fed Pernambuco, Recife, PE, BrazilUniv Fed Campina Grande, Campina Grande, PB, BrazilUniv Fed Maranhao, Sao Luis, MA, BrazilUniv Fed Parana, BR-80060000 Curitiba, Parana, BrazilUniv Fed Paraiba, BR-58059900 Joao Pessoa, Paraiba, BrazilHosp Maternidade Fernando Magalhaes, Rio de Janeiro, RJ, BrazilUniv Fed Rio Grande do Sul, Porto Alegre, RS, BrazilHosp Maternidade Celso Pierro, Campinas, SP, BrazilInst Fernandes Figueira Fiocruz, Rio de Janeiro, RJ, BrazilHosp Israelita Albert Einstein, São Paulo, BrazilUniv State São Paulo, Botucatu, SP, BrazilJundiai Sch Med, Jundiai, SP, BrazilUniv São Paulo, BR-14049 Ribeirao Preto, SP, BrazilSanta Casa Limeira, Limeira, SP, BrazilSanta Casa Sao Carlos, Sao Carlos, SP, BrazilMaternidade Leonor Mendes de Barros, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilCNPq: 402702/2008-5Web of Scienc

    A moral panic? The problematization of forced marriage in British newspapers

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    This paper examines the British media’s construction of forced marriage as an urgent social problem in a context where other forms of violence against women are not similarly problematised. A detailed analysis of four British newspapers over a ten-year period demonstrates that media reporting of forced marriage constitutes a moral panic in that it is constructed as a cultural problem that threatens Britain’s social order rather than as a specific form of violence against women. Thus, the current problematisation of forced marriage restricts discursive spaces for policy debates and hinders attempts to respond to this problem as part of broader efforts to tackle violence against women

    Rhodiola rosea L.:from golden root to green cell factories

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    Rhodiola rosea L. is a worldwide popular plant with adaptogenic activities that have been and currently are exploited in the traditional medicine of many countries, as well as, examined in a number of clinical trials. More than 140 chemical structures have been identified which belong to several natural product classes, including phenylpropanoid glycosides, phenylethanoids, flavonoids and essential oils, and are mainly stored in the rhizomes and the roots of the plant. A number of mechanisms contribute to the adaptogenic activities of R. rosea preparations and its phytochemical constituents. Among them, the intrinsic inducible mammalian stress responses and their effector proteins, such as heat shock protein 70 (Hsp70), are the most prominent. Due to its popular medicinal use, which has led to depletion of its natural habitats, R. rosea is now considered as endangered in most parts of the world. Conservation, cultivation and micropropagation are all implemented as potential preservation strategies. A number of in vitro systems of R. rosea are being developed as sources of pharmaceutically valuable secondary metabolites. These are greatly facilitated by advances in elucidation of the biosynthetic pathways and the enzymes, which catalyse the production of these secondary metabolites in the plant. In addition, biotechnological approaches show promise towards achieving sustainable production of R. rosea secondary metabolites.</p

    Is Aggressive Surgical Palliation of Proximal Bile Duct Cancer With Involvement of Both Main Hepatic Ducts Worthwhile?

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    The only curative treatment for proximal bile duct cancer with involvement of both main hepatic ducts is liver transplantation. Most patients do not fulfill the requirements for liver transplantation. Our treatment strategy in appropriate cases is palliative tumor resection and reconstruction of the biliary passage by sutureless bilioenteric anastomosis. We have treated 12 patients, 5 in combination with intraluminal and percutaneous radiotherapy. Our results indicate that this strategy leads to effective palliation in some cases provided that only microscopic residual tumor is left in-situ. Our survival times compare favourably with survival after liver transplantation
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