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1.
Phys Rev Lett ; 120(12): 123201, 2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29694100

RESUMO

We demonstrate one-dimensional sub-Doppler laser cooling of a beam of YbF molecules to 100 µK. This is a key step towards a measurement of the electron's electric dipole moment using ultracold molecules. We compare the effectiveness of magnetically assisted and polarization-gradient sub-Doppler cooling mechanisms. We model the experiment and find good agreement with our data.

2.
Clin Diabetes ; 36(2): 168-173, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29686456

RESUMO

IN BRIEF This study was conducted to ascertain the opinions of endocrinologists about diabetes care as it relates to the health care provider workforce. A survey was administered to endocrinologists in the Planning Research in Inpatient Diabetes and Planning Research in Outpatient Diabetes (PRIDE/PROUD) group and given to attendees of the American Diabetes Association (ADA) Scientific Sessions special interest group whose focus was primary care. The majority of respondents agreed that there is a need for more providers to be trained to take care of patients with diabetes and that more trained providers are needed, and almost half agreed that primary care providers (PCPs) with advanced training in diabetes should be part of the workforce for managing the diabetes pandemic. Expanding diabetes fellowship programs for PCPs remains an important potential solution for addressing workforce development needs in diabetes care.

3.
Endocr Pract ; 23(3): 331-341, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27967226

RESUMO

OBJECTIVE: Inpatient hyperglycemia, hypoglycemia, and glucose variability are associated with increased mortality. The use of an electronic glucose management system (eGMS) to guide intravenous (IV) insulin infusion has been found to significantly improve blood glucose (BG) control. This retrospective observational study evaluated the 7-year (January 2009-December 2015) impact of the EndoTool® eGMS in intensive and intermediate units at Vidant Medical Center, a 900-bed tertiary teaching hospital. METHODS: Patients assigned to eGMS had indications for IV insulin infusion, including uncontrolled diabetes, stress hyperglycemia, and/or postoperative BG levels >140 mg/dL. This study evaluated time required to achieve BG control (<180 mg/dL; <140 mg/dL for cardiovascular surgery patients); hypoglycemia incidence (<70 and <40 mg/dL); glucose variability (assessed by SD and coefficient of variation percentage [CV%]); excursions (BG levels >180 mg/dL after control attained); and the impact of eGMS on hospital-acquired condition (HAC)-8 rates. RESULTS: Data were available for all treated patients (492,078 BG readings from 16,850 patients). With eGMS, BG levels were brought to target within 1.5 to 2.3 hours (4.5 to 4.8 hours for cardiovascular patients). Minimal hypoglycemia was observed (BG values <70 mg/dL, 0.93%; <40 mg/dL, 0.03%), and analysis of variance of BG values <70 mg/dL showed significant reductions over time in hypoglycemia frequency, from 1.04% in 2009 to 0.46% in 2015 (P<.0001). The CV% per patient visit was 26.5 (±12.9)%, and 4% of patients experienced glucose excursions (defined as BG levels >180 mg/dL once control was attained). HAC-8 rates were reduced from 0.083 per 1,000 patients (2008) to 0.032 per 1,000 patients (2011). CONCLUSION: The use of eGMS resulted in rapid, effective control of inpatient BG levels, including significantly reduced hypoglycemia rates. ABBREVIATIONS: BG = blood glucose CMS = Centers for Medicare and Medicaid Services CV = coefficient of variation CV% = coefficient of variation percentage eGMS = electronic glucose management system GV = glycemic variability HAC = Hospital-Acquired Condition ICU = intensive care unit IU = intermediate unit IV = intravenous LOS = length of stay VMC = Vidant Medical Center.


Assuntos
Glicemia/metabolismo , Quimioterapia Assistida por Computador/métodos , Cuidados Críticos , Quimioterapia Assistida por Computador/normas , Humanos , Hiperglicemia/tratamento farmacológico , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Insulina/administração & dosagem , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Controle de Qualidade , Estudos Retrospectivos , Centros de Atenção Terciária
4.
Phys Rev Lett ; 114(8): 081802, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25768755

RESUMO

Searches are performed for resonant and nonresonant Higgs boson pair production in the γγbb[over ¯] final state using 20 fb^{-1} of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the ATLAS detector at the CERN Large Hadron Collider. A 95% confidence level upper limit on the cross section times branching ratio of nonresonant production is set at 2.2 pb, while the expected limit is 1.0 pb. The difference derives from a modest excess of events, corresponding to 2.4 standard deviations from the background-only hypothesis. The limit observed in the search for a narrow X→hh resonance ranges between 0.7 and 3.5 pb as a function of the resonance mass.

5.
Phys Rev Lett ; 114(7): 072302, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25763955

RESUMO

Measurements of inclusive jet production are performed in pp and Pb+Pb collisions at √(s)NN=2.76 TeV with the ATLAS detector at the LHC, corresponding to integrated luminosities of 4.0 and 0.14 nb(-1), respectively. The jets are identified with the anti-k(t) algorithm with R=0.4, and the spectra are measured over the kinematic range of jet transverse momentum 32

6.
Phys Rev Lett ; 113(14): 141803, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25325632

RESUMO

This Letter presents the first study of W(±)W(±)jj, same-electric-charge diboson production in association with two jets, using 20.3 fb(-1) of proton-proton collision data at sqrt[s] = 8 TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with two reconstructed same-charge leptons (e(±)e(±), e(±)µ(±), and µ(±)µ(±)) and two or more jets are analyzed. Production cross sections are measured in two fiducial regions, with different sensitivities to the electroweak and strong production mechanisms. First evidence for W(±)W(±)jj production and electroweak-only W(±)W(±)jj production is observed with a significance of 4.5 and 3.6 standard deviations, respectively. The measured production cross sections are in agreement with standard model predictions. Limits at 95% confidence level are set on anomalous quartic gauge couplings.

8.
Phys Rev Lett ; 113(21): 212004, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25479491

RESUMO

A search for excited states of the Bc(±) meson is performed using 4.9 fb(-1) of 7 TeV and 19.2 fb(-1) of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter detected in the decay Bc(±)→J/ψπ(±). The state appears in the m(Bc(±)π(+)π(-))-m(Bc(±))-2m(π(±)) mass difference distribution with a significance of 5.2 standard deviations. The mass of the observed state is 6842±4±5 MeV, where the first error is statistical and the second is systematic. The mass and decay of this state are consistent with expectations for the second S-wave state of the Bc(±) meson, Bc(±)(2S).

9.
Phys Rev Lett ; 112(9): 091804, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24655244

RESUMO

This Letter presents a search for quantum black-hole production using 20.3 fb-1 of data collected with the ATLAS detector in pp collisions at the LHC at √s = 8 TeV. The quantum black holes are assumed to decay into a final state characterized by a lepton (electron or muon) and a jet. In either channel, no event with a lepton-jet invariant mass of 3.5 TeV or more is observed, consistent with the expected background. Limits are set on the product of cross sections and branching fractions for the lepton+jet final states of quantum black holes produced in a search region for invariant masses above 1 TeV. The combined 95% confidence level upper limit on this product for quantum black holes with threshold mass above 3.5 TeV is 0.18 fb. This limit constrains the threshold quantum black-hole mass to be above 5.3 TeV in the model considered.


Assuntos
Partículas Elementares , Modelos Teóricos , Teoria Quântica , Elétrons , Mésons
10.
Phys Rev Lett ; 113(17): 171801, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25379911

RESUMO

A search for scalar particles decaying via narrow resonances into two photons in the mass range 65-600 GeV is performed using 20.3 fb(-1) of √s 8 TeV pp collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches.

11.
Phys Rev Lett ; 107(4): 041802, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21866993

RESUMO

This Letter presents a measurement of the W+ W- production cross section in sqrt(s) = 7 TeV pp collisions by the ATLAS experiment, using 34 pb(-1) of integrated luminosity produced by the Large Hadron Collider at CERN. Selecting events with two isolated leptons, each either an electron or a muon, 8 candidate events are observed with an expected background of 1.7 ± 0.6 events. The measured cross section is 41(-16)(+20)(stat) ± 5(syst)±1(lumi) pb, which is consistent with the standard model prediction of 44 ± 3 pb calculated at next-to-leading order in QCD.

12.
Phys Rev Lett ; 106(13): 131802, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21517374

RESUMO

This Letter presents the first search for supersymmetry in final states containing one isolated electron or muon, jets, and missing transverse momentum from √s=7 TeV proton-proton collisions at the LHC. The data were recorded by the ATLAS experiment during 2010 and correspond to a total integrated luminosity of 35 pb(-1). No excess above the standard model background expectation is observed. Limits are set on the parameters of the minimal supergravity framework, extending previous limits. Within this framework, for A(0)=0 GeV, tanß=3, and µ>0 and for equal squark and gluino masses, gluino masses below 700 GeV are excluded at 95% confidence level.

13.
Phys Rev Lett ; 106(17): 172002, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21635030

RESUMO

Azimuthal decorrelations between the two central jets with the largest transverse momenta are sensitive to the dynamics of events with multiple jets. We present a measurement of the normalized differential cross section based on the full data set (∫Ldt=36 pb(-1)) acquired by the ATLAS detector during the 2010 sqrt(s)=7 TeV proton-proton run of the LHC. The measured distributions include jets with transverse momenta up to 1.3 TeV, probing perturbative QCD in a high-energy regime.

14.
Phys Rev Lett ; 106(25): 251801, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21770629

RESUMO

This Letter presents the first search for a heavy particle decaying into an e ± µ(-/+) final state in sqrt[s] = 7 TeV pp collisions at the LHC. The data were recorded by the ATLAS detector during 2010 and correspond to a total integrated luminosity of 35 pb(-1). No excess above the standard model background expectation is observed. Exclusions at 95% confidence level are placed on two representative models. In an R-parity violating supersymmetric model, tau sneutrinos with a mass below 0.75 TeV are excluded, assuming all R-parity violating couplings are zero except λ(311)' = 0.11 and λ312 = 0.07. In a lepton flavor violating model, a Z'-like vector boson with masses of 0.70-1.00 TeV and corresponding cross sections times branching ratios of 0.175-0.183 pb is excluded. These results extend to higher mass R-parity violating sneutrinos and lepton flavor violating Z's than previous constraints from the Tevatron.


Assuntos
Elétrons , Mésons , Física/instrumentação , Simulação por Computador
15.
Acta Cytol ; 53(5): 517-23, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19798878

RESUMO

OBJECTIVE: To address the likelihood of thyroid malignancy for each cytologic interpretation, highly cellular and benign vs. follicular carcinoma, with particular attention to the indeterminate cytologic result, follicular neoplasm. STUDY DESIGN: We retrospectively reviewed thyroid nodule cytologic and histologic interpretations from 1994 to 2002 in a tertiary medical center setting. Patients were referred for evaluation of thyroid nodules found incidentally or on physical examination. RESULTS: A total of 886 thyroid nodules were aspirated in 802 patients (500 benign, 195 indeterminate, 129 inadequate, 62 malignant). Of 195 indeterminate lesions, 180 were classified as follicular neoplasm or "cannot rule out/possible" follicular neoplasm, with 144 of these ultimately removed and with malignant histologic findings in 28. Any mention of follicular neoplasm in the cytology report conferred a 19.4% risk of malignancy in patients who went on to surgery (including an unexpected 18.2% rate of malignancy in the subcategory in which a possible follicular neoplasm was a secondary listing in an otherwise-benign cytologic differential diagnosis). CONCLUSION: There was no difference in the likelihood of histologic malignancy between the cytologic subcategories of "definite "follicular neoplasm and "cannot rule out/possible" follicular neoplasm. We recommend that cytologic reports on fine needle aspiration of thyroid nodules with a diagnosis of follicular neoplasm reflect this fact.


Assuntos
Adenoma/patologia , Biópsia por Agulha Fina , Carcinoma Papilar/patologia , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/cirurgia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/cirurgia , Adulto Jovem
16.
Eur Phys J C Part Fields ; 76(4): 199, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28260972

RESUMO

The centrality dependence of the mean charged-particle multiplicity as a function of pseudorapidity is measured in approximately 1 [Formula: see text]b[Formula: see text] of proton-lead collisions at a nucleon-nucleon centre-of-mass energy of [Formula: see text] [Formula: see text] using the ATLAS detector at the Large Hadron Collider. Charged particles with absolute pseudorapidity less than 2.7 are reconstructed using the ATLAS pixel detector. The [Formula: see text] collision centrality is characterised by the total transverse energy measured in the Pb-going direction of the forward calorimeter. The charged-particle pseudorapidity distributions are found to vary strongly with centrality, with an increasing asymmetry between the proton-going and Pb-going directions as the collisions become more central. Three different estimations of the number of nucleons participating in the [Formula: see text] collision have been carried out using the Glauber model as well as two Glauber-Gribov inspired extensions to the Glauber model. Charged-particle multiplicities per participant pair are found to vary differently for these three models, highlighting the importance of including colour fluctuations in nucleon-nucleon collisions in the modelling of the initial state of [Formula: see text] collisions.

17.
Trends Microbiol ; 6(5): 198-202, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9614344

RESUMO

Recent studies have identified at least nine distinct receptors used by the piconaviruses for cell entry. Does the evolution of receptor usage correlate with the different tropisms observed in this group of viruses, and does this influence pathogenesis, or is it the consequence of another selection mechanism that favours virus survival?


Assuntos
Picornaviridae/fisiologia , Receptores Virais/fisiologia , Animais , Humanos , Picornaviridae/crescimento & desenvolvimento , Picornaviridae/patogenicidade , Tropismo
18.
Trends Microbiol ; 2(11): 449-54, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7866703

RESUMO

All three live, attenuated vaccine strains of poliovirus contain important attenuation determinants in a short conserved sequence in the 5' noncoding region. Evidence suggests these act by weakening a secondary-structural element critical for the unusual mechanism of translational initiation of picornaviruses, in which ribosomes bind directly to a site far downstream of the 5' end. Understanding the molecular basis of attenuation may allow novel vaccine strains to be designed.


Assuntos
Região Variável de Imunoglobulina/genética , Vacina Antipólio Oral , Poliovirus/genética , Poliovirus/patogenicidade , Sequência de Bases , Região Variável de Imunoglobulina/fisiologia , Dados de Sequência Molecular , Biossíntese de Proteínas/fisiologia , Estrutura Secundária de Proteína , Vacinas Atenuadas , Virulência/genética , Replicação Viral
19.
J Mol Biol ; 207(2): 379-92, 1989 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-2547075

RESUMO

A secondary structure model for the 5' non-coding RNA of poliovirus has been derived by comparing computer-generated folding patterns of equivalent sequences from a number of related enteroviruses and rhinoviruses and identifying compensating mutations that suggest conservation of a common secondary structure. Although certain elements are similar, the new model differs considerably from a previously published minimal energy structure and is consistent with the observed sensitivity of in vitro RNA transcripts of infectious poliovirus cDNA to RNases and modifying chemicals. The sequence of a neurovirulent revertant of an attenuated mutant provides additional evidence for an interaction between a region known to be important for neurovirulence, sequence 471-483, and nucleotides 528 to 538.


Assuntos
Poliovirus/genética , RNA Viral/genética , Animais , Sequência de Bases , Camundongos , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Conformação de Ácido Nucleico , Poliovirus/metabolismo , Poliovirus/patogenicidade , RNA Viral/metabolismo , Medula Espinal/microbiologia
20.
Thyroid ; 15(2): 170-5, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15753678

RESUMO

Papillary thyroid carcinoma (PTC) commonly metastasizes to cervical lymph nodes. Distant metastases are unusual with the lungs most frequently involved. Well-differentiated thyroid carcinoma very rarely presents with metastases to the spleen. This is the case of a 25-year-old man with a history of PTC (1.4 cm primary; no capsular invasion and negative lymph node metastases). One year after initial surgery, recurrent disease was found in multiple neck nodes by central neck dissection. Whole body scan (WBS) following a therapeutic ablation dose of 150 mCi I(131) revealed mediastinal metastases. Computerized axial tomography (CT) of the chest one year later showed no gross mediastinal or pulmonary disease. However, multiple large splenic lesions were incidentally noted. Evaluation by ultrasound (US) showed lesions to be solid echogenic masses without remarkable Doppler characteristics to suggest vascular tumors. US-guided percutaneous fine-needle aspiration biopsy (FNAB) of one lesion was nondiagnostic. After withdrawal from Levothyroxine, serum TSH was >100 mU/L with a thyroglobulin of 9.4 ng/mL and negative anti-thyroglobulin antibodies. Diagnostic WBS revealed faint splenic uptake but was otherwise unremarkable. Following treatment with 192 mCi I(131), WBS demonstrated increased activity in the mediastinum as well as in the spleen suggesting mediastinal and splenic metastases. Contrast CT of the abdomen showed multiple low-attenuated heterogeneously enhancing splenic masses, normal liver and no intra-abdominal lymphadenopathy. The largest mass (4.5 x 3.5 cm) was exophytic and in close proximity to the splenic capsule. Despite the serum thyroglobulin of only 9.4 ng/mL, the finding of I(131) accumulation within solid splenic masses led to a preoperative diagnosis of thyroid carcinoma metastases. To establish the diagnosis and to remove the risk for splenic rupture, a laparoscopic splenectomy was performed. Histopathologic analysis showed large littoral cell angiomas (LCA). False-positive radioiodine scintigraphy in the setting of PTC involving a vertebral hemangioma has been reported. To our knowledge, this is the first case that describes multiple angiomas mimicking metastatic thyroid carcinoma to the spleen. In one-third of all cases reported, LCA co-exists with various visceral organ cancers or malignant lymphoma. This is the first report of an association between LCA and thyroid carcinoma.


Assuntos
Carcinoma Papilar/secundário , Hemangioma/patologia , Neoplasias Esplênicas/secundário , Neoplasias da Glândula Tireoide/patologia , Adulto , Carcinoma Papilar/diagnóstico por imagem , Diagnóstico Diferencial , Reações Falso-Positivas , Feminino , Hemangioma/diagnóstico por imagem , Humanos , Radioisótopos do Iodo , Cintilografia , Neoplasias Esplênicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler
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