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1.
Phys Rev Lett ; 128(13): 132501, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426696

RESUMO

We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst) ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010 GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157 GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15 fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15 fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.

2.
Phys Rev Lett ; 125(11): 112502, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32976004

RESUMO

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.

3.
Phys Rev Lett ; 111(14): 141803, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24152148

RESUMO

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 µA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.

4.
Science ; 183(4131): 1289-91, 1974 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-17791368

RESUMO

The Mariner 10 spacecraft encountered Venus at 1701 G.M.T. on 5 February 1974. The preplanned encounter science sequence was executed satisfactorily, accomplishing all objectives despite a number of spacecraft problems that had occurred in the early phases of the flight. Seven experiments were conducted, including observations of the solar wind interaction region, extreme ultraviolet and infrared emissions, radio occultation, and imaging.

5.
Science ; 185(4146): 141-2, 1974 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-17810505

RESUMO

Mariner 10's closet approach to Mercury on 29 March 1974 occurred on the dark side of the planet at a range of approximately 700 kilometers. The spacecraft trajectory passed through the shadows of both the sun and Earth. Experiments conducted included magnetic fields, plasma and charged particle studies of the solar wind interaction region, television photography, extreme ultraviolet spectroscopy of the atmosphere, the detection of infrared thermal radiation from the surface, and a dual-frequency radio occultation in search of an ionosphere.

6.
Science ; 204(4400): 1405-6, 1979 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17814195

RESUMO

During some 3 months of orbital operations, Seasat collected a unique set of global synoptic data on ocean winds, waves, temperature, and topography. All indications from a preliminary analysis of these data are that most of the mission's proof-of-concept objective-the demonstration of nearly all-weather microwave surveillance of the world's oceans-will be met.

9.
Chest ; 105(3): 864-7, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8131553

RESUMO

Relapsing polychondritis is a rare multisystem disease. We describe the presentation and treatment of a patient with relapsing polychondritis and review the literature. This patient had involvement of the tracheobronchial tree requiring insertion of metallic stents.


Assuntos
Broncopatias/etiologia , Policondrite Recidivante/complicações , Stents , Estenose Traqueal/etiologia , Idoso , Broncopatias/terapia , Cuidados Críticos , Feminino , Humanos , Policondrite Recidivante/terapia , Respiração Artificial , Aço Inoxidável , Estenose Traqueal/terapia
10.
Br J Ophthalmol ; 63(11): 762-7, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-389282

RESUMO

We present the results of a double-blind trial comparing the efficacy of betamethasone phosphate 0.1%, clobetasone butyrate 0.1%, and placebo in the treatment of acute unilateral nongranulomatous uveitis. The 2 steroids were equally comparable in improvement of the patients' symptoms, though betamethasone phosphate was significantly more effective than clobetasone butyrate in improving the ocular signs of uveitis. However, clobetasone butyrate had significantly less effect on raising intraocular pressure in known steroid responders and ocular hypertensives than did dexamethasone. The use of a bolometer as an objective measure in uveitis was significant only in the more severe cases of uveitis. In comparing the placebo group of patients with those on topical steroids, the former group, though improving, appeared to lag behind by approximately one week. Four cases on placebo, however, had to be withdrawn because of worsening of the condition. Mild cases of anterior uveitis would probably resolve without using topical steroids.


Assuntos
Betametasona/análogos & derivados , Betametasona/uso terapêutico , Clobetasol/uso terapêutico , Uveíte/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Betametasona/farmacologia , Ensaios Clínicos como Assunto , Clobetasol/análogos & derivados , Clobetasol/farmacologia , Método Duplo-Cego , Feminino , Humanos , Pressão Intraocular/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Uveíte/diagnóstico
11.
Br J Ophthalmol ; 74(5): 313-4, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-1693855

RESUMO

Two well controlled non-insulin dependent diabetics with background retinopathy underwent endocapsular lens extraction with in-the-bag posterior chamber implantation. In the postoperative period rubeosis iridis set in abruptly. The fellow eyes showed no progression of retinopathy and the diabetic status showed no deterioration. The cause of neovascularisation and the role of intra- versus extracapsular extraction with implantation are discussed.


Assuntos
Retinopatia Diabética/patologia , Iris/irrigação sanguínea , Lentes Intraoculares , Neovascularização Patológica/patologia , Complicações Pós-Operatórias/etiologia , Idoso , Diabetes Mellitus Tipo 2/patologia , Humanos , Masculino , Disco Óptico/irrigação sanguínea , Retina/patologia , Acuidade Visual
12.
Br J Ophthalmol ; 69(2): 120-5, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3881125

RESUMO

We have compared the anti-inflammatory efficacy of 5% tolmetin sodium dihydrate, 0.5% prednisolone disodium phosphate, and 0.1% betamethasone disodium phosphate in 71 consecutive patients presenting with acute endogenous non-granulomatous uveitis randomly assigned to one of these treatment groups. Inflammatory symptoms and signs were scored during the course of the 21-day trial period. There was no statistically significant difference in the effect on the signs or symptoms of the three drugs tested. 90% of the Betnesol (betamethasone sodium phosphate, benzalkonium chloride) treated group were clinically judged cured compared with 68% of the Predsol (prednisolone sodium phosphate, benzalkonium chloride) treated group, and 57% of the tolmetin treated group.


Assuntos
Anti-Inflamatórios/uso terapêutico , Betametasona/análogos & derivados , Dexametasona/análogos & derivados , Prednisolona/análogos & derivados , Pirróis/uso terapêutico , Tolmetino/uso terapêutico , Uveíte/tratamento farmacológico , Administração Tópica , Adolescente , Adulto , Idoso , Betametasona/uso terapêutico , Ensaios Clínicos como Assunto , Feminino , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico
13.
Nucl Med Commun ; 12(11): 959-63, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1754156

RESUMO

Sixty-three patients undergoing isotope ventilation/perfusion scintigraphy for suspected pulmonary embolism were monitored using pulse oximetry. Xenon inhalation had no adverse effect on arterial oxygen saturation. Fifty-seven per cent of patients demonstrated a drop in oxygen saturation of 2-10% within 5 min of injection of macroaggregates. Small changes in arterial oxygen saturation reflect larger changes in the arteriole partial pressure of oxygen. In 10 patients, oxygen saturation dropped to 91% and below, corresponding to an arterial pO2 of less than 60 mm Hg. The effect lasted up to 30 min and is thought unlikely to be simply due to arteriolar blockade. Falls in arterial oxygen saturation cannot be correlated with any specific pulmonary pathology and appear unlikely to be of any clinical significance in most patients.


Assuntos
Oxigênio/sangue , Embolia Pulmonar/diagnóstico por imagem , Agregado de Albumina Marcado com Tecnécio Tc 99m , Administração por Inalação , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Oximetria , Pressão Parcial , Embolia Pulmonar/sangue , Cintilografia , Radioisótopos de Xenônio/administração & dosagem
14.
Br J Oral Maxillofac Surg ; 51(8): e282-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23510790

RESUMO

Operation is the mainstay of treatment for rhinophyma. Numerous techniques for dermaplaning and dermabrasion have been described with typical healing times of roughly 3 weeks. We present a case that combined use of the Versajet™ (Smith & Nephew, UK) system with ReCell(®) non-cultured autologous skin cells (Avita Medical, UK) to expedite re-epithelialisation. After sculpting with Versajet™, a 1cm(2) split-thickness skin biopsy specimen was harvested for application of autologous skin. Postoperative pictures at 6 days show well-formed epithelial buds, and at 9 days the nose was fully healed. The application of ReCell(®) hastened healing. This could potentially avoid hypertrophic scars and lessen the number of visits to outpatients for dressing to be changed, rendering it more advantageous than other techniques.


Assuntos
Desbridamento/métodos , Rinofima/cirurgia , Transplante de Pele/métodos , Irrigação Terapêutica/métodos , Idoso , Autoenxertos/transplante , Desbridamento/instrumentação , Seguimentos , Humanos , Masculino , Reepitelização/fisiologia , Irrigação Terapêutica/instrumentação , Coleta de Tecidos e Órgãos/métodos , Cicatrização/fisiologia
16.
BMJ Case Rep ; 20112011 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-22696633

RESUMO

A patient of Pakistani-origin was admitted to Bradford Royal Infirmary, UK, following a 3-week history of cough, headache and general malaise. He had recently spent 10 weeks in Pakistan and on return had been diagnosed in the community with Swine flu. He developed abdominal pain and diarrhoea in the week prior to admission, and presented to hospital with fever, tachycardia and raised inflammatory markers. He deteriorated rapidly, developing signs of peritonism and Salmonella paratyphi A was grown from blood cultures. CT demonstrated a small volume of free fluid within the abdomen and the patient underwent laparotomy. A small bowel perforation was resected and a side to side anastomosis fashioned. Treatment with intravenous antibiotics was completed and the patient was discharged 9 days postoperatively.


Assuntos
Valva Ileocecal , Perfuração Intestinal/etiologia , Febre Paratifoide/complicações , Antibacterianos/uso terapêutico , Diagnóstico Diferencial , Humanos , Valva Ileocecal/cirurgia , Perfuração Intestinal/diagnóstico , Perfuração Intestinal/cirurgia , Masculino , Paquistão/etnologia , Febre Paratifoide/diagnóstico , Febre Paratifoide/tratamento farmacológico , Salmonella paratyphi A , Viagem
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