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.
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}â0) where they should be most reliable.
Assuntos
Algoritmos , Queimaduras/terapia , Telefone Celular , Hidratação/métodos , Aplicativos Móveis , Feminino , Humanos , MasculinoAssuntos
Queimaduras/cirurgia , Materiais Revestidos Biocompatíveis/uso terapêutico , Dermabrasão/métodos , Intervenção Médica Precoce/métodos , Transplante de Pele/métodos , Adolescente , Queimaduras/economia , Criança , Pré-Escolar , Protocolos Clínicos , Materiais Revestidos Biocompatíveis/economia , Análise Custo-Benefício , Dermabrasão/economia , Intervenção Médica Precoce/economia , Feminino , Humanos , Lactente , Masculino , Transplante de Pele/economia , Resultado do TratamentoRESUMO
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.
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/fisiologiaAssuntos
Aneurisma da Aorta Abdominal , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Aneurisma da Aorta Abdominal/tratamento farmacológico , Aneurisma da Aorta Abdominal/patologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Metanálise como Assunto , Revisões Sistemáticas como AssuntoRESUMO
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 , ViagemRESUMO
A large data set of charged-pion (pi+/-) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-->pion production mechanisms.
RESUMO
BACKGROUND: Impaired cerebral oxygenation, which is reflected by measuring jugular bulb oxygenation, is thought to play an important role in the development of neurological injury after cardiac operations with cardiopulmonary bypass (CPB). The effects of cardiopulmonary temperature and blood gas strategy on cerebral oxygenation are not fully appreciated. METHODS: Sixty patients were randomly allocated into four equal groups (cold alpha-stat, cold pH-stat, warm alpha-stat and warm pH-stat) to compare the effect of these perfusion strategies on cerebral oxygenation monitored by jugular bulb oximetry [jugular bulb oxygen saturation (SjO(2)) and arterial-jugular bulb oxygen content difference (AjDO(2))]. Jugular bulb oxygen saturation and AjDO(2) were measured before CPB, after 5, 20, 40 min on CPB, at start and end of rewarming, 5 min before the end of CPB and 10 min after CPB. Two-way analysis of variance was used to model the lowest SjO(2) and highest AjDO(2) during CPB, with CPB temperature and blood gas management as contributing factors. RESULTS: Significant changes in SjO(2) were only related to the type of blood gas management, with no significant difference between warm and cold CPB patients. In addition, during rewarming, desaturation (SjO(2) = 50%) occurred in seven patients of 30 in the alpha-stat groups and in one patient of 30 in the pH-stat groups (P = 0.021), and in five patients of 30 in the cold groups vs. three of 30 in the warm groups (P = 0.434). However, no significant changes were found in the highest AjDO(2) between the four groups. CONCLUSION: Cold CPB failed to offer any further brain protection in terms of better preservation of cerebral oxygenation than warm CPB. Therefore, warm CPB (34 degrees C) with different blood gas strategies appears to be a satisfactory alternative to cold CPB (28 degrees C).
Assuntos
Encéfalo/metabolismo , Ponte Cardiopulmonar , Ponte de Artéria Coronária , Oxigênio/metabolismo , Idoso , Gasometria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , TemperaturaRESUMO
BACKGROUND: The effect of cardiopulmonary bypass temperature and blood gas management on the brain is still controversial. This study was designed to compare the changes in S100beta protein concentration and Mini-Mental State Examination in patients undergoing cold (28 degrees C) vs. warm (34 degrees C) cardiopulmonary bypass using different blood gas strategies (alpha-stat and pH-stat). METHODS: Sixty patients were randomly allocated to one of four equal groups (cold alpha-stat, cold pH-stat, warm alpha-stat, warm pH-stat). Serum S100beta concentrations were measured before CPB, directly after CPB, at 4.5 h and at 24 h after CPB. Mini-Mental State Examination was performed one day before surgery and on day five after the operation. Antegrade warm blood cardioplegia (37 degrees C) was used in all patients. RESULTS: There was no significant difference in postoperative S100beta protein levels between the four groups. Also, there was no interaction between bypass temperature and type of blood gas strategy on S100beta levels after bypass (directly after bypass, 4.5 h and 24 h after bypass). Mini-Mental State Examination score was not affected by blood gas strategy but it was significantly lower in patients undergoing cold cardiopulmonary bypass surgery: median (range), 26 (12-29) vs. 27 (23-30) in warm patients, P = 0.014. There was no significant correlation between Mini-Mental State Examination score 5 days after CPB and S100beta levels at any of the studied time-points after CPB. CONCLUSION: These results support the use of warm CPB (34 degrees C) in patients undergoing coronary artery bypass surgery regardless of the type of blood gas strategy.
Assuntos
Dióxido de Carbono/sangue , Ponte Cardiopulmonar/métodos , Transtornos Cognitivos/diagnóstico , Entrevista Psiquiátrica Padronizada , Proteínas S100/sangue , Temperatura , Ponte Cardiopulmonar/efeitos adversos , Transtornos Cognitivos/etiologia , Ponte de Artéria Coronária , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Fatores de Crescimento Neural , Subunidade beta da Proteína Ligante de Cálcio S100RESUMO
The first measurements of the d(gamma,p)n differential cross section at forward angles and photon energies above 4 GeV were performed at the Thomas Jefferson National Accelerator Facility (JLab). The results indicate evidence of an angular dependent scaling threshold. Results at straight theta(cm) = 37 degrees are consistent with the constituent counting rules for E(gamma) greater, similar 4 GeV, while those at 70 degrees are consistent with the constituent counting rules for E(gamma) greater, similar 1.5 GeV.