590 research outputs found

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    Crossing the `Yellow Void' -- Spatially Resolved Spectroscopy of the Post- Red Supergiant IRC+10420 and Its Circumstellar Ejecta

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    IRC +10420 is one of the extreme hypergiant stars that define the empirical upper luminosity boundary in the HR diagram. During their post--RSG evolution, these massive stars enter a temperature range (6000-9000 K) of increased dynamical instability, high mass loss, and increasing opacity, a semi--forbidden region, that de Jager and his collaborators have called the `yellow void'. We report HST/STIS spatially resolved spectroscopy of IRC +10420 and its reflection nebula with some surprising results. Long slit spectroscopy of the reflected spectrum allows us to effectively view the star from different directions. Measurements of the double--peaked Halpha emission profile show a uniform outflow of gas in a nearly spherical distribution, contrary to previous models with an equatorial disk or bipolar outflow. Based on the temperature and mass loss rate estimates that are usually quoted for this object, the wind is optically thick to the continuum at some and possibly all wavelengths. Consequently the observed variations in apparent spectral type and inferred temperature are changes in the wind and do not necessarily mean that the underlying stellar radius and interior structure are evolving on such a short timescale. To explain the evidence for simultaneous outflow and infall of material near the star, we propose a `rain' model in which blobs of gas condense in regions of lowered opacity outside the dense wind. With the apparent warming of its wind, the recent appearance of strong emission, and a decline in the mass loss rate, IRC +10420 may be about to shed its opaque wind, cross the `yellow void', and emerge as a hotter star.Comment: To appear in the Astronomical Journal, August 200

    Collage Vol. II

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    JUDY COCHRAN: Editorial, 4-5 ROBERTA CHAPMEN: Photo, 6 ANITRA CHUGHTAI (Translations): Haikus, 7 CHARLES O\u27KEEFE: Photo, 8 MARK VANDERLINDE-ABERNATHY, ALYSSA LANDRY (Translator): Memories of a Spider (Les souvenirs d\u27une araignee), 9 MARK VANDERLINE-ABERNATHY, AMY NORSKOG (Translator): Tomato Fields (Champ de tomates), 10 SARAH BISHOP, HEFEDH ZANINA (Translator): Dear John (Cher John), 11 RYAN BUTZ (Translator): Basho\u27s Haiku, Issa\u27s Haiku, 12-13 JENNIFER HUMBERT, FADOUA EL BOUAMRAOUI (Translator): Pressed Lips (Levres Serrees), 15 ADELE REEVES (Translator): Contemporary song by Mr. Children, 16-17 BRODY PAGEL, GRACE DUGAR (Translator): The Lizard King (Le Roi Lezard), 18 JIMMY PIPKIN (Translator): In Love with You, 19 MOLLY ROSCOE: Saturday Night at Rusty\u27s (Samedi Soir a Rusty\u27s), 20 CHARLES O\u27KEEFE: Photo, 21 MATT MESSMER (Translator): Waseda University School Song, 22-23 TIMOTHY COOPER: Wenn du grosh bist
 (When you\u27re Tall
), 24 DAVID HARMAN: Der Dunkle Stern (The Dark Star), 25 ANN TOWNSEND, JUDY COCHRAN (Translator): From a Window (D\u27une Fenetre), 26-27 SARA CAHILL: El sauce lloron (The Weeping Willow), 28-32 CHARLES O\u27KEEFE: Photo, 30 JENNIFER HUMBERT, MATT BISHOP: Past, Present (passe, present), 33 CAROL GENEYA KAPLAN, FADOUA EL BOUAMRAOUI (Translator): Une Autre Femme (Another Woman), 34-35 CHARLES O\u27KEEFE: Photo, 36 ANN TOWNSEND, JUDY COCHRAN (Translator): The Mowers (Les Faucheurs), 37 PRISCILLA PATON: Photo, 38 GONZALO TUESTA: La Grande Dame De Paris (The Great Lady of Paris), 39 SARAH PILLERDORF (Translator): Japanese Cartoons by Tezuka Osamu, 41-45 DANIELLE GERKEN: Schuhe der Heimat (Boots of Home), 47 CURTIS PLOWGIAN: Le peste de la langue francaise, 48-52 PRISCILLA PATON: Photo, 50 ZANE HOUSEHOLDER: Vive la Republique! (Film), 54 JENNIFER ZIMMER: EL tenis y las frustraciones (Tennis and Frustrations), La tumba de Ben (Ben\u27s Grave), 56-57 AUTUMN LOTZE: Times Square in the rain, 58-59 CHARLES O\u27KEEFE: Photo, 60 STEPHEN M. JULKA: Colors of the Earth, 61 THOMAS BRESSOUD: Java, 62 ERIC NELSON: World, 63 SARAH CLAPP (Translator): At a long day\u27s end (Natsume Soseki), A friend has come and is now leaving, Eating persimmons (Masaoka Shiki), 64 CHARLES O\u27KEEFE: Photo, 65 JOHN BURZYNSKI, MEGAN FETTER (Translator): Home is where the heart is, 66 RICHARD BANAHAN: Photo, 67 KIM FREEMAN: Baltimore, 68 JACOB RIDRIGUEZ-NOBLE: Home (Heimat), 69 SUZANNE KENNEDY: Oft verberge ich mich (Oft I hide myself), 70 RICHARD BANAHAN: Photo, 7

    Tim-3 expression defines a novel population of dysfunctional T cells with highly elevated frequencies in progressive HIV-1 infection

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    Progressive loss of T cell functionality is a hallmark of chronic infection with human immunodeficiency virus 1 (HIV-1). We have identified a novel population of dysfunctional T cells marked by surface expression of the glycoprotein Tim-3. The frequency of this population was increased in HIV-1–infected individuals to a mean of 49.4 ± SD 12.9% of CD8+ T cells expressing Tim-3 in HIV-1–infected chronic progressors versus 28.5 ± 6.8% in HIV-1–uninfected individuals. Levels of Tim-3 expression on T cells from HIV-1–infected inviduals correlated positively with HIV-1 viral load and CD38 expression and inversely with CD4+ T cell count. In progressive HIV-1 infection, Tim-3 expression was up-regulated on HIV-1–specific CD8+ T cells. Tim-3–expressing T cells failed to produce cytokine or proliferate in response to antigen and exhibited impaired Stat5, Erk1/2, and p38 signaling. Blocking the Tim-3 signaling pathway restored proliferation and enhanced cytokine production in HIV-1–specific T cells. Thus, Tim-3 represents a novel target for the therapeutic reversal of HIV-1–associated T cell dysfunction

    Effects of Tobacco Taxation and Pricing on Smoking Behavior in High Risk Populations: A Knowledge Synthesis

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    Tobacco taxation is an essential component of a comprehensive tobacco control strategy. However, to fully realize the benefits it is vital to understand the impact of increased taxes among high-risk subpopulations. Are they influenced to the same extent as the general population? Do they need additional measures to influence smoking behavior? The objectives of this study were to synthesize the evidence regarding differential effects of taxation and price on smoking in: youth, young adults, persons of low socio-economic status, with dual diagnoses, heavy/long-term smokers, and Aboriginal people. Using a better practices approach, a knowledge synthesis was conducted using a systematic review of the literature and an expert advisory panel. Experts were involved in developing the study plan, discussing findings, developing policy recommendations, and identifying priorities for future research. Most studies found that raising cigarette prices through increased taxes is a highly effective measure for reducing smoking among youth, young adults, and persons of low socioeconomic status. However, there is a striking lack of evidence about the impact of increasing cigarette prices on smoking behavior in heavy/long-term smokers, persons with a dual diagnosis and Aboriginals. Given their high prevalence of smoking, urgent attention is needed to develop effective policies for the six subpopulations reviewed. These findings will be of value to policy-makers and researchers in their efforts to improve the effectiveness of tobacco control measures, especially with subpopulations at most risk. Although specific studies are needed, tobacco taxation is a key policy measure for driving success

    Evaluation of unclassified variants in the breast cancer susceptibility genes BRCA1 and BRCA2 using five methods: results from a population-based study of young breast cancer patients

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    Introduction Efforts are ongoing to determine the significance of unclassified variants (UVs) in the breast cancer susceptibility genes BRCA1/BRCA2, but no study has systematically assessed whether women carrying the suspected deleterious UVs have characteristics commonly seen among women carrying known deleterious or disease-causing mutations in BRCA1/BRCA2. Methods We sequenced BRCA1/BRCA2 in 1,469 population-based female breast cancer patients diagnosed between the ages of 20 and 49 years. We used existing literature to classify variants into known deleterious mutations, polymorphic variants, and UVs. The UVs were further classified as high risk or low risk based on five methods: allele frequency, Polyphen algorithm, sequence conservation, Grantham matrix scores, and a combination of the Grantham matrix score and sequence conservation. Furthermore, we examined whether patients who carry the variants classified as high risk using these methods have risk characteristics similar to patients with known deleterious BRCA1/BRCA2 mutations (early age at diagnosis, family history of breast cancer or ovarian cancer, and negative estrogen receptor/progesterone receptor). Results We identified 262 distinct BRCA1/BRCA2 variants, including 147 UVs, in our study population. The BRCA1 UV carriers, but not the BRCA2 UV carriers, who were classified as high risk using each classification method were more similar to the deleterious mutation carriers with respect to family history than those carriers classified as low risk. For example, the odds ratio of having a first-degree family history for the high-risk women classified using Polyphen was 3.39 (95% confidence interval = 1.16 to 9.94) compared with normal/polymorphic BRCA1 carriers. The corresponding odds ratio of low-risk women was 1.53 (95% confidence interval = 1.07 to 2.18). The odds ratio for high-risk women defined by allele frequency was 2.00 (95% confidence interval = 1.14 to 3.51), and that of low-risk women was 1.30 (95% confidence interval = 0.87 to 1.93). Conclusion The results suggest that the five classification methods yielded similar results. Polyphen was particularly better at isolating BRCA1 UV carriers likely to have a family history of breast cancer or ovarian cancer, and may therefore help to classify BRCA1 UVs. Our study suggests that these methods may not be as successful in classifying BRCA2 UVs

    Calpeptin is a potent cathepsin inhibitor and drug candidate for SARS-CoV-2 infections

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    Several drug screening campaigns identified Calpeptin as a drug candidate against SARS-CoV-2. Initially reported to target the viral main protease (Mpro), its moderate activity in Mpro inhibition assays hints at a second target. Indeed, we show that Calpeptin is an extremely potent cysteine cathepsin inhibitor, a finding additionally supported by X-ray crystallography. Cell infection assays proved Calpeptin’s efficacy against SARS-CoV-2. Treatment of SARS-CoV-2-infected Golden Syrian hamsters with sulfonated Calpeptin at a dose of 1 mg/kg body weight reduces the viral load in the trachea. Despite a higher risk of side effects, an intrinsic advantage in targeting host proteins is their mutational stability in contrast to highly mutable viral targets. Here we show that the inhibition of cathepsins, a protein family of the host organism, by calpeptin is a promising approach for the treatment of SARS-CoV-2 and potentially other viral infections

    An ecological study on the relationship between supply of beds in long-term care institutions in Italy and potential care needs for the elderly

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    <p>Abstract</p> <p>Background</p> <p>The ageing population in Europe is putting an ever increasing demand on the long-term care (LTC) services provided by these countries. This study analyses the relationship between the LTC institutional supply of beds and potential care needs, taking into account the social and health context, the supply of complementary and alternative services, along with informal care.</p> <p>Methods</p> <p>An observational, cross-sectional, ecological study was carried out. Statistical data were obtained from the Italian National Institute of Statistics and Ministry of Health. Indicators, regarding 5 areas (Supply of beds in long term care institutions, Potential care needs, Social and health context, Complementary and alternative services for the elderly, Informal care), were calculated at Local Health Unit (LHU) level and referred to 2004.</p> <p>Two indicators were specifically used to measure supply of beds in long term care institutions and potential care needs for the elderly. Their values were grouped in tertiles. LHU were classified according to the combination of tertiles in three groups: A. High level of supply of beds in long term care institutions associated with low level of potential care needs; B. Low level of supply of beds in long term care institutions associated with high level of potential care needs; C. Balanced level of supply of beds in long term care institutions with potential care needs. For each group the indicators of 5 areas were analysed.</p> <p>The Index Number (IN) was calculated for each of these indicators.</p> <p>Results</p> <p>Specific factors that need to be carefully considered were highlighted in each of the three defined groups. The highest level of alternative services such as long-stay hospital discharges in residence region (IN = 125), home care recipients (HCR) (IN = 123.8) were reported for Group A. This group included North regions. The highest level of inappropriate hospital discharges in (IN = 124.1) and out (IN = 155.8) the residence region, the highest value of families who received help (IN = 106.4) and the lowest level of HCR (IN = 68.7) were found in Group B. South regions belong to this group. The highest level of families paying a caregiver (IN = 115.8) was shown in Group C. Central regions are included in third group.</p> <p>Conclusion</p> <p>Supply of beds in long term care institutions substantially differs across Italian regions, showing in every scenario some imbalances between potential care needs and other studied factors. Our study suggests the need of a comprehensive rethinking of care delivery "system".</p
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