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1.
Phys Rev Lett ; 118(25): 251301, 2017 Jun 23.
Article de Anglais | MEDLINE | ID: mdl-28696731

RÉSUMÉ

New results are reported from the operation of the PICO-60 dark matter detector, a bubble chamber filled with 52 kg of C_{3}F_{8} located in the SNOLAB underground laboratory. As in previous PICO bubble chambers, PICO-60 C_{3}F_{8} exhibits excellent electron recoil and alpha decay rejection, and the observed multiple-scattering neutron rate indicates a single-scatter neutron background of less than one event per month. A blind analysis of an efficiency-corrected 1167-kg day exposure at a 3.3-keV thermodynamic threshold reveals no single-scattering nuclear recoil candidates, consistent with the predicted background. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.4×10^{-41} cm^{2} for a 30-GeV c^{-2} WIMP, more than 1 order of magnitude improvement from previous PICO results.

2.
Phys Rev Lett ; 116(7): 071301, 2016 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-26943526

RÉSUMÉ

The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^{2}.

3.
Phys Rev Lett ; 114(11): 111302, 2015 Mar 20.
Article de Anglais | MEDLINE | ID: mdl-25839256

RÉSUMÉ

While the standard model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically produced relativistic particles with electric charge lower than e/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers finds no candidates, thereby excluding new parameter space for particles with electric charges between e/6 and e/200.

4.
Phys Rev Lett ; 112(24): 241302, 2014 Jun 20.
Article de Anglais | MEDLINE | ID: mdl-24996080

RÉSUMÉ

We report a first search for weakly interacting massive particles (WIMPs) using the background rejection capabilities of SuperCDMS. An exposure of 577 kg days was analyzed for WIMPs with mass <30 GeV/c(2), with the signal region blinded. Eleven events were observed after unblinding. We set an upper limit on the spin-independent WIMP-nucleon cross section of 1.2×10(-42) cm(2) at 8 GeV/c(2). This result is in tension with WIMP interpretations of recent experiments and probes new parameter space for WIMP-nucleon scattering for WIMP masses <6 GeV/c(2).

5.
Phys Rev Lett ; 112(4): 041302, 2014 Jan 31.
Article de Anglais | MEDLINE | ID: mdl-24580434

RÉSUMÉ

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

6.
J Hum Nutr Diet ; 27 Suppl 2: 90-7, 2014 Apr.
Article de Anglais | MEDLINE | ID: mdl-23738786

RÉSUMÉ

BACKGROUND: Weight management interventions can be extended using mobile telephone technology to deliver support in real-time, real-world settings. The present study aimed to determine whether text messaging helped patients maintain or lose weight following a weight-loss programme. METHODS: In this controlled study, overweight and obese [body mass index (BMI) >30 kg m(-2) or >28 kg m(-2) with co-morbidities] adults who completed a weight-loss programme participated in an additional 12-week text message intervention [Lifestyle, Eating and Activity Programme (LEAP) Beep]. Patients were allocated goals for steps, fruit, vegetable and breakfast consumption. Patients regularly 'texted' their progress and received tailored practitioner feedback. Pre/post-intervention body weight, waist circumference (WC), BMI, quality of life (QOL), anxiety and depression measurements were compared retrospectively with a control group offered weight checks only. RESULTS: Compared to control (n = 17), the intervention group's (n = 17) body weight, WC and BMI reduced significantly (-1.6 versus 0.7 kg, P = 0.006; -2.2 versus 1.5 cm, P = 0.0005; -0.6 versus 0.7 kg m(-2) , P = 0.03, respectively). QOL and depression scores also improved (-6.8 versus 1 point, P = 0.134; -0.2 versus 0.2 points, P = 0.228). No difference was observed in anxiety scores between the groups. Intervention versus control group follow-up attendance improved significantly (4.4 versus 1.7 attendances, P = 0.0005). CONCLUSIONS: LEAP Beep promoted losses in weight, WC and BMI, and improved QOL parameters and follow-up attendance. Text messaging is a cheap, portable, convenient and innovative medium facilitating goal setting, self-monitoring and information exchange. Further improvements to automation at the same time as maintaining individual support are necessary to ease practitioner burden. Text messaging offers cost-efficient dietetic input, opening up possibilities for practitioner-to-patient support and yields positive weight outcomes following initial weight loss.


Sujet(s)
Surpoids/thérapie , Envoi de messages textuels , Programmes de perte de poids/méthodes , Sujet âgé , Indice de masse corporelle , Femelle , Études de suivi , Humains , Mode de vie , Mâle , Adulte d'âge moyen , Obésité/thérapie , Qualité de vie , Études rétrospectives , Tour de taille , Perte de poids
7.
Phys Rev Lett ; 111(25): 251301, 2013 Dec 20.
Article de Anglais | MEDLINE | ID: mdl-24483735

RÉSUMÉ

We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors of the CDMS II experiment. This blind analysis of 140.2 kg day of data taken between July 2007 and September 2008 revealed three WIMP-candidate events with a surface-event background estimate of 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons and 206Pb are limited to <0.13 and <0.08 events at the 90% confidence level, respectively. The exposure of this analysis is equivalent to 23.4 kg day for a recoil energy range of 7-100 keV for a WIMP of mass 10 GeV/c2. The probability that the known backgrounds would produce three or more events in the signal region is 5.4%. A profile likelihood ratio test of the three events that includes the measured recoil energies gives a 0.19% probability for the known-background-only hypothesis when tested against the alternative WIMP+background hypothesis. The highest likelihood occurs for a WIMP mass of 8.6 GeV/c2 and WIMP-nucleon cross section of 1.9×10(-41) cm2.

8.
Phys Rev Lett ; 106(13): 131302, 2011 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-21517371

RÉSUMÉ

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10 GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.

9.
Science ; 327(5973): 1619-21, 2010 Mar 26.
Article de Anglais | MEDLINE | ID: mdl-20150446

RÉSUMÉ

Astrophysical observations indicate that dark matter constitutes most of the mass in our universe, but its nature remains unknown. Over the past decade, the Cryogenic Dark Matter Search (CDMS II) experiment has provided world-leading sensitivity for the direct detection of weakly interacting massive particle (WIMP) dark matter. The final exposure of our low-temperature germanium particle detectors at the Soudan Underground Laboratory yielded two candidate events, with an expected background of 0.9 +/- 0.2 events. This is not statistically significant evidence for a WIMP signal. The combined CDMS II data place the strongest constraints on the WIMP-nucleon spin-independent scattering cross section for a wide range of WIMP masses and exclude new parameter space in inelastic dark matter models.

10.
J Pathol ; 194(1): 68-75, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11329143

RÉSUMÉ

Mutations of the p53 tumour suppressor gene have been found in most human cancers, including ovarian epithelial malignancies. This study investigated whether the presence or absence of p53 mutation was associated with outcome following platinum-based chemotherapy in patients with ovarian cancer. DNA samples from tumour tissue and blood were obtained from 73 patients with primary tumours, 50 of whom received platinum-based adjuvant chemotherapy. Single-strand conformation polymorphism analysis and direct DNA sequencing of exons 5-8 detected mutations in 44% (32 of 73) of tumours. These were more common in late-stage (III or IV) than in early-stage disease (I or II) (p=0.03). There was no association with histological type, volume of residual disease following surgery, or initial CA125 levels. No significant association was found between p53 status and overall survival or disease-free survival following chemotherapy. Likewise, there was no correlation between p53 mutation and response to chemotherapy as defined by normalization of CA125 levels. Tumours with p53 missense mutations recurred within a significantly shorter time than those with normal p53 (p=0.04). In addition, there was a tendency for tumours with missense mutations to have a shorter disease-free survival than those with non-missense mutations, although this did not reach statistical significance (p=0.07).


Sujet(s)
Gènes p53 , Mutation , Tumeurs de l'ovaire/génétique , Marqueurs biologiques tumoraux/sang , Antigènes CA-125/sang , Traitement médicamenteux adjuvant , Survie sans rechute , Femelle , Études de suivi , Humains , Analyse multifactorielle , Mutation faux-sens , Tumeurs de l'ovaire/traitement médicamenteux , Tumeurs de l'ovaire/anatomopathologie , Réaction de polymérisation en chaîne , Polymorphisme de conformation simple brin , Pronostic , Taux de survie
11.
Med Sci Law ; 39(3): 214-8, 1999 Jul.
Article de Anglais | MEDLINE | ID: mdl-10466315

RÉSUMÉ

Supervised discharge was introduced, against much professional opposition, in the Mental Health (Patients in the Community) Act 1995. All patients subject to supervised discharge (SD) in a large health district were identified by medical records departments, and the outcome of their SD on 1 October 1997, eighteen months after the legislation came into effect, was assessed. In that first eighteen months, half of the general, rehabilitation and forensic psychiatrists in the trust used SD for 22 patients. Of the 12 orders in effect for over six months, six were renewed at six months and three at one year. In spite of professional hostility and scepticism about the clinical practicalities of SD, the use of the new power has gradually increased with experience. Outcomes to date seem generally positive, but further definitive research is needed.


Sujet(s)
Post-cure/législation et jurisprudence , Troubles mentaux/rééducation et réadaptation , Services de santé mentale/législation et jurisprudence , Adulte , Angleterre , Femelle , Humains , Mâle , , Pays de Galles
12.
Nutr Health ; 3(4): 247-54, 1985.
Article de Anglais | MEDLINE | ID: mdl-4069467

RÉSUMÉ

Food is a primary necessity of life and worldwide governments have a substantial influence on the foods offered for human consumption. Principal movement is concerned with supply of foods through assistance to farmers in general aiming to maintain a fair standard of return for those involved in agriculture. Further involvement relates to quality of foods (microbiological safety) and with consumer protection against unfair trading practice. Government economic policies influence demand for foods whilst educational strategies can stimulate particular food choices. Present nutritional ideas recommend changes to diet as part of programmes designated to reduce incidence of conditions such as coronary heart disease. It is a government responsibility to provide clear information on foods and nutrition. Rational government involvement can lead to better nutrition for the population whilst stimulating an efficient agricultural industry.


Sujet(s)
Approvisionnement en nourriture , Gouvernement , Humains , Royaume-Uni , États-Unis
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