35 research outputs found

    A Tiltable Single-Shot Miniature Dilution Refrigerator for Astrophysical Applications

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    We present a 3He / 4He dilution refrigerator designed for cooling astronomical mm-wave telescope receivers to around 100 mK. Used in combination with a Gifford-McMahon closed-cycle refrigerator, 4He and 3He sorption-pumped refrigerators, our cryogen-free system is capable of achieving 2 microW cooling power at 87 mK. A receiver attached directly to the telescope optics is required to rotate with respect to the downward direction. This scenario, of variable tilt, has proved difficult for typical dilution refrigerators, but our design has a geometry chosen to allow tilt to 45 degrees and beyond.Comment: 7 pages, 11 figures. Accepted by Cryogenic

    A male patient with acromegaly and breast cancer: treating acromegaly to control tumor progression

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    BACKGROUND: Acromegaly is a rare disease associated with an increased risk of developing cancer. CASE PRESENTATION: We report the case of a 72-year-old man who was diagnosed with acromegaly (IGF-1 770 ng/ml) and breast cancer. Four years before he suffered from a colon-rectal cancer. Pituitary surgery and octreotide-LAR treatment failed to control acromegaly. Normalization of IGF-1 (97 ng/ml) was obtained with pegvisomant therapy. Four years after breast cancer surgery, 2 pulmonary metastases were detected at chest CT. The patient was started on anastrozole, but, contrary to medical advice, he stopped pegvisomant treatment (IGF-I 453 ng/ml). Four months later, chest CT revealed an increase in size of the metastatic lesion of the left lung. The patient was shifted from anastrozole to tamoxifen and was restarted on pegvisomant, with normalization of serum IGF-1 levels (90 ng/ml). Four months later, a reduction in size of the metastatic lesion of the left lung was detected by CT. Subsequent CT scans throughout a 24-month follow-up showed a further reduction in size and then a stabilization of the metastasis. CONCLUSIONS: This is the first report of a male patient with acromegaly and breast cancer. The clinical course of breast cancer was closely related to the metabolic control of acromegaly. The rapid progression of metastatic lesion was temporally related to stopping pegvisomant treatment and paralleled a rise in serum IGF-1 levels. Normalization of IGF-1 after re-starting pegvisomant impressively reduced the progression of metastatic breast lesions. Control of acromegaly is mandatory in acromegalic patients with cancer

    Luminescence and Structural Characterization of Gd2O2S Scintillators Doped with Tb3+, Ce3+, Pr3+ and F for Imaging Applications

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    none14siRadiodiagnostic technologies are powerful tools for preventing diseases and monitoring the condition of patients. Medicine and sectors such as industry and research all use this inspection methodology. This field demands innovative and more sophisticated systems and materials for improving resolution and sensitivity, leading to a faster, reliable, and safe diagnosis. In this study, a large characterization of gadolinium oxysulfide (Gd2O2S) scintillator screens for imaging applications has been carried out. Seven scintillator samples were doped with praseodymium (Pr3+), terbium (Tb3+) activators and co-doped with praseodymium, cerium, and fluorine (Gd2O2S:Pr,Ce,F). The sample screens were prepared in the laboratory in the form of high packing density screens, following the methodology used in screen sample preparation in infrared spectroscopy and luminescence. Parameters such as quantum detection efficiency (QDE), energy absorption efficiency (EAE), and absolute luminescence efficiency (ALE) were evaluated. In parallel, a structural characterization was performed, via XRD and SEM analysis, for quality control purposes as well as for correlation with optical properties. Spatial resolution properties were experimentally evaluated via the Modulation Transfer Function. Results were compared with published data about Gd2O2S:Pr,Ce,F screens produced with a standard method of a sedimentation technique. In particular, the ALE rose with the X-ray tube voltage up to 100 kVp, while among the different dopants, Gd2O2S:Pr exhibited the highest ALE value. When comparing screens with different thicknesses, a linear trend for the ALE value was not observed; the highest ALE value was measured for the 0.57 mm thick Gd2O2S:Pr,Ce,F sample, while the best MTF values were found in the thinner Gd2O2S:Pr,Ce,F screen with 0.38 mm thickness.De Martinis, Alessia; Montalto, Luigi; Scalise, Lorenzo; Rinaldi, Daniele; Mengucci, Paolo; Michail, Christos; Fountos, George; Martini, Nicki; Koukou, Vaia; Valais, Ioannis; Bakas, Athanasios; Fountzoula, Christine; Kandarakis, Ioannis; David, StratosDe Martinis, Alessia; Montalto, Luigi; Scalise, Lorenzo; Rinaldi, Daniele; Mengucci, Paolo; Michail, Christos; Fountos, George; Martini, Nicki; Koukou, Vaia; Valais, Ioannis; Bakas, Athanasios; Fountzoula, Christine; Kandarakis, Ioannis; David, Strato

    Nutrition, diet and immunosenescence

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    Ageing is characterized by immunosenescence and the progressive decline in immunity in association with an increased frequency of infections and chronic disease. This complex process affects both the innate and adaptive immune systems with a progressive decline in most immune cell populations and defects in activation resulting in loss of function. Although host genetics and environmental factors, such as stress, exercise and diet can impact on the onset or course of immunosenescence, the mechanisms involved are largely unknown. This review focusses on identifying the most significant aspects of immunosenescence and on the evidence that nutritional intervention might delay this process, and consequently improve the quality of life of the elderly

    Inflammation, genetic background and longevity

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    Ageing is an inexorable intrinsic process that affects all cells, tissues, organs and individuals. Due to a diminished homeostasis and increased organism frailty, ageing causes a reduction of the response to environmental stimuli and, in general, is associated to an increased predisposition to illness and death. Actually, it is characterized by a state of reduced ability to maintain health and general homeodynamics of the organism.Alarge part of the ageing phenotype is explained by an imbalance between inflammatory and anti-inflammatory networks, which results in the low grade chronic pro-inflammatory status of ageing, ‘‘inflamm-ageing’’. It is strictly linked to immunosenescence, and on the whole they are the major contributory factors to the increased frequency of morbidity and mortality among elderly. Inflammageing is compatible with longevity; even if centenarians have an increased level of inflammatory mediators in comparison to old subjects and they are very frail, they also have high level of anti-inflammatory cytokines together with protective genotypes. Actually, data on case control studies performed in Italian centenarians suggest that a pro-inflammatory genotype is unfavourable to reach extreme longevity in good health and likely favours the onset of age-related diseases such as cardiovascular diseases and Alzheimer’s disease, the leading causes of mortality and disability in the elderly. However, many associations between gene variants and longevity have been found only in Italian population. This should not be unexpected, since ageing and longevity are complex traits resulting not only and not exclusively from genetics, but rather from the interactions between genetics, environment and chance

    Millimetric Site Testing at Dome C: Results and Plans

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    AbstractResults relative to three campaigns at Dome Concordia, aimed to measure the millimetric sky noise, are presented. The atmospheric noise during summer seems to be definitely lower with respect to that measured with the same instrumentation in other geographical locations. We illustrate the scientific results obtained
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