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1.
Phys Rev Lett ; 132(13): 133201, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613284

RESUMO

We implement coherent delocalization as a tool for improving the two primary metrics of atomic clock performance: systematic uncertainty and instability. By decreasing atomic density with coherent delocalization, we suppress cold-collision shifts and two-body losses. Atom loss attributed to Landau-Zener tunneling in the ground lattice band would compromise coherent delocalization at low trap depths for our ^{171}Yb atoms; hence, we implement for the first time delocalization in excited lattice bands. Doing so increases the spatial distribution of atoms trapped in the vertically oriented optical lattice by ∼7 times. At the same time, we observe a reduction of the cold-collision shift by 6.5(8) times, while also making inelastic two-body loss negligible. With these advantages, we measure the trap-light-induced quenching rate and natural lifetime of the ^{3}P_{0} excited state as 5.7(7)×10^{-4} E_{r}^{-1} s^{-1} and 19(2) s, respectively.

2.
Phys Rev Lett ; 129(11): 113202, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154423

RESUMO

Laser cooling is a key ingredient for quantum control of atomic systems in a variety of settings. In divalent atoms, two-stage Doppler cooling is typically used to bring atoms to the µK regime. Here, we implement a pulsed radial cooling scheme using the ultranarrow ^{1}S_{0}-^{3}P_{0} clock transition in ytterbium to realize subrecoil temperatures, down to tens of nK. Together with sideband cooling along the one-dimensional lattice axis, we efficiently prepare atoms in shallow lattices at an energy of 6 lattice recoils. Under these conditions key limits on lattice clock accuracy and instability are reduced, opening the door to dramatic improvements. Furthermore, tunneling shifts in the shallow lattice do not compromise clock accuracy at the 10^{-19} level.

3.
Rev Sci Instrum ; 92(3): 033201, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820059

RESUMO

We create a pair of symmetric Bitter-type electromagnet assemblies capable of producing multiple field configurations including uniform magnetic fields, spherical quadruple traps, or Ioffe-Pritchard magnetic bottles. Unlike other designs, our coil allows both radial and azimuthal cooling water flows by incorporating an innovative 3D-printed water distribution manifold. Combined with a double-coil geometry, such orthogonal flows permit stacking of non-concentric Bitter coils. We achieve a low thermal resistance of 4.2(1) °C kW-1 and high water flow rate of 10.0(3) l min-1 at a pressure of 190(10) kPa.

4.
Chest ; 98(3): 550-3, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2118446

RESUMO

The purpose of this study was to determine whether there are any consistent spirometric or Dsb findings in patients with LV dysfunction characterized by a clinical diagnosis of CHF and an EF less than 40 percent. We performed spirometry and Dsb in 34 patients, and found that EF correlated only with Dsb. When we separated the patients into those with rales and those without, Dsb correlated strongly with EF only in those with rales. There was no correlation with other spirometric values. Mean Dsb percent predicted was significantly lower in patients with rales despite similar mean EF. Only two of 23 patients without rales had a reduced Dsb while only one of 11 with rales had a normal Dsb. We conclude that Dsb is a good predictor of clinically evident heart failure. When rales are absent, Dsb should be normal in patients with LV dysfunction; when present, Dsb will be diminished in proportion to the EF.


Assuntos
Cardiopatias/fisiopatologia , Capacidade de Difusão Pulmonar , Idoso , Dióxido de Carbono/fisiologia , Feminino , Cardiopatias/complicações , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Mecânica Respiratória , Sons Respiratórios , Volume Sistólico
5.
Chest ; 94(3): 580-3, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3261680

RESUMO

Pneumocystis carinii pneumonia is a frequent manifestation of the acquired immune deficiency syndrome (AIDS). It usually presents radiologically as diffuse bilateral infiltrates and histologically as a foamy, eosinophilic intra-alveolar exudate containing the organisms' cysts. We recently studied two rare cases of P carinii pneumonia presenting as pulmonary nodules on chest x-ray films in two patients with AIDS. The corresponding histologies were a combination of the usual intra-alveolar pattern, with an alveolar and interstitial granulomatous appearance. Pneumocystis carinii was present in both areas and was the only organism found in the tissues examined. A third case presented with the more common radiographic appearance but also had a granulomatous histology. We conclude that P carinii pneumonia should be considered in the differential diagnosis of pulmonary nodules in immunocompromised patients and that pathologists should be aware of the possibility of a granulomatous reaction to this organism.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Pneumonia por Pneumocystis/patologia , Adulto , Feminino , Granuloma/complicações , Granuloma/diagnóstico por imagem , Granuloma/patologia , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pneumonia por Pneumocystis/complicações , Pneumonia por Pneumocystis/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
Bone Marrow Transplant ; 18(3): 569-72, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8879619

RESUMO

Three patients who developed acute onset of cerebral blindness within 5-47 days of BMT using tacrolimus (FK506) as primary GVHD prophylaxis are described. This syndrome has been described with the use of cyclosporin A (CsA) and FK506 in solid organ transplant recipients. CsA-induced cerebral blindness has also been noted in BMT recipients but to date there have been no reports of this complication in BMT patients receiving FK506. We have noted a striking similarity in the clinical and radiographic presentations between these patients and those with CsA-associated cerebral blindness. Reversibility within 1-2 weeks of onset and the potential for substitution of CsA for FK506 in these patients is described.


Assuntos
Cegueira/etiologia , Transplante de Medula Óssea , Encéfalo/efeitos dos fármacos , Imunossupressores/efeitos adversos , Tacrolimo/efeitos adversos , Adulto , Ciclosporina/efeitos adversos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
7.
Psychopharmacology (Berl) ; 73(4): 314-7, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6789350

RESUMO

The effects of diazepam (10 mg orally) on the responding of normal human volunteers was studied in a procedure that involved the maintenance of operant behavior by monetary reinforcement and its suppression by monetary loss (punishment). Diazepam produced an antipunishment effect as shown by an increase in behavior suppressed by monetary loss. An analogy to animal procedures that selectively detect antianxiety drugs is apparent.


Assuntos
Condicionamento Operante/efeitos dos fármacos , Diazepam/farmacologia , Adulto , Feminino , Humanos , Masculino , Placebos , Esquema de Reforço , Reforço Psicológico , Fatores de Tempo
8.
AJNR Am J Neuroradiol ; 16(6): 1287-91, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7677027

RESUMO

PURPOSE: To determine whether patients who have acute graft-versus-host disease (AGVHD), are more likely to have radiographically abnormal paranasal sinuses after bone marrow transplantation than patients without AGVHD. METHODS: This retrospective case-control study population comprised 45 adult allogeneic or matched unrelated donor patients who underwent bone marrow transplantation. Twenty-eight patients had AGVHD, and 17 patients did not. All patients had paranasal sinus imaging with either CT or plain films for evaluation of possible sinusitis after bone marrow transplantation. The severity of radiographic changes was measured with an objective scoring system based on mucosal findings. RESULTS: An odds ratio revealed no association between AGVHD and the presence of radiographically abnormal sinuses. CONCLUSION: The diagnosis of AGVHD should not complicate the radiographic evaluation of acute sinusitis after bone marrow transplantation.


Assuntos
Transplante de Medula Óssea , Doença Enxerto-Hospedeiro/diagnóstico por imagem , Doenças dos Seios Paranasais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Doença Aguda , Adulto , Transplante de Medula Óssea/imunologia , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Doença Enxerto-Hospedeiro/imunologia , Humanos , Tolerância Imunológica/imunologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Doenças dos Seios Paranasais/imunologia , Estudos Retrospectivos , Sinusite/diagnóstico por imagem
9.
J Hand Surg Br ; 18(2): 182-3, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8501368

RESUMO

A case is presented of an anomalous course of the palmar cutaneous branch of the median nerve. Wide and meticulous exposure is necessary to avoid injury to all variations of this nerve and the use of a "safe" incision will not always avoid risk of injury.


Assuntos
Síndrome do Túnel Carpal/cirurgia , Nervo Mediano/anatomia & histologia , Humanos , Complicações Intraoperatórias/prevenção & controle , Masculino , Nervo Mediano/lesões , Nervo Mediano/cirurgia , Pessoa de Meia-Idade , Pele/inervação , Procedimentos Cirúrgicos Operatórios/métodos
10.
Hand Clin ; 7(2): 283-93, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1880163

RESUMO

Acute injuries of the distal radioulnar joint are common. They often are not treated aggressively owing to a failure to diagnose or the misconception that there is little functional impairment if left untreated. Early aggressive treatment with restoration of anatomic alignment and stability will yield optimum results. Acute treatment usually produces a better functional outcome than late reconstructive procedures.


Assuntos
Luxações Articulares/cirurgia , Rádio (Anatomia)/lesões , Ulna/lesões , Traumatismos do Punho/cirurgia , Doença Aguda , Humanos , Rádio (Anatomia)/cirurgia , Fraturas do Rádio/complicações , Fraturas do Rádio/cirurgia , Ulna/cirurgia , Traumatismos do Punho/complicações
12.
J Arthroplasty ; 6(4): 317-20, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1770367

RESUMO

Twenty-six adult cadavers were utilized in an anatomic study designed to measure intramedullary femoral alignment in relation to the anterosuperior iliac spine. Fifty femurs were measured to determine the reliability of the anterosuperior iliac spine as an accurate landmark for distal femoral resection in total knee arthroplasty (TKA). A precision machined stainless steel U-shaped parallel alignment guide was fabricated and inserted into the femoral canals of intact adult cadavers. The guide's relationship to the anterosuperior iliac spine was measured and recorded. All hips were maintained in neutral alignment. Independent variables recorded included gender, knee alignment, and side of lower extremity. The range for medial deviation was 1-28 mm for the right femur and 2-25 mm for the left femur (average, 8.5 mm). The range for lateral deviation was 3-14 mm for the right femur and 2-17 mm for the left femur (average, 10.3 mm). There was no statistical correlation between the independent variables of side measured, gender, and measured offset at the anterosuperior iliac spine. Based on this highly variable pattern of alignment, utilizing simulated intraoperative technique, use of the anterosuperior iliac spine does not provide a landmark accurate enough to repeatedly produce a distal femoral resection within 2 degrees-3 degrees of ideal. Use of the anterosuperior iliac spine may lead to less than ideal femoral resection and malpositioning of total knee components.


Assuntos
Artroplastia/instrumentação , Fêmur/anatomia & histologia , Ílio/anatomia & histologia , Prótese do Joelho , Fêmur/cirurgia , Humanos , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/cirurgia , Métodos , Equipamentos Cirúrgicos
13.
Clin Orthop Relat Res ; (315): 231-3, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7634672

RESUMO

One hundred knees that underwent primary total knee arthroplasties were divided into 2 groups: the first 50 consecutive knees were assigned retrospectively to Group I (control), and the following 50 knees were assigned prospectively to Group II (early flexion). All procedures were cementless meniscal-bearing total knee arthroplasties and were performed by the same surgeon. Maximum early flexion (Group II) resulted in decreased length of stay, decreased hospital costs, and increased range of motion at 1 year. In light of current government interest in hospital cost reduction, this method should be considered as an attractive alternative to continuous passive motion.


Assuntos
Prótese do Joelho , Tempo de Internação , Terapia Passiva Contínua de Movimento , Idoso , Idoso de 80 Anos ou mais , Feminino , Custos Hospitalares , Humanos , Prótese do Joelho/economia , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Terapia Passiva Contínua de Movimento/economia , Estudos Prospectivos , Estudos Retrospectivos
14.
Infect Immun ; 48(2): 280-6, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-3886543

RESUMO

Cell membranes of Streptococcus mutans BHT serotype b were prepared after glass bead disruption or mutanolysin digestion of whole cells. Immunoblot analyses of BHT membrane extracts revealed major polypeptides of 42,000, 46,000, 62,000, and 82,000 daltons, as well as several minor bands, to be reactive with rabbit anti-human heart immunoglobulins. Heart cross-reactive antigens have been reported in the cell walls and culture fluids of several S. mutans serotypes. This represents the first report of cell membrane-localized heart cross-reactive antigens in this oral pathogen. Positive enzyme-linked immunosorbent assay and immunoblot reactions were also obtained with heart tissue antigen and anti-BHT sera, indicating mutual cross-reactivity. The major cross-reactive component detected by immunoblotting of human heart extracts was a 69,000-dalton polypeptide.


Assuntos
Antígenos de Bactérias/imunologia , Antígenos de Superfície/imunologia , Miocárdio/imunologia , Streptococcus mutans/imunologia , Proteínas de Bactérias/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Humanos , Técnicas Imunológicas , Peso Molecular
15.
J Clin Psychopharmacol ; 12(1): 43-8, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1552039

RESUMO

The Neurobehavioral Assessment Scale (NAS) was developed to measure the full range of behavioral functioning from fully alert to deep coma. This investigator-rated scale was evaluated in 60 patients undergoing conscious sedation for maxillofacial procedures. The results obtained on the NAS were reliable, as evidenced by high correlations between the rating of the two raters. The scale is also valid as determined by high correlations between the NAS and a standard scale, the Glasgow Coma Scale (criterion validity) and between the NAS and the Digit Symbol Substitution Test (behavioral validity). The NAS clearly distinguished between two levels of sedation (heavy and light). Furthermore, the NAS appears to be better able to discriminate among the different degrees of sedation in lightly sedated patients than the Glasgow Coma Scale.


Assuntos
Sedação Consciente/psicologia , Testes Neuropsicológicos , Adolescente , Adulto , Idoso , Nível de Alerta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários
16.
Infect Immun ; 31(2): 808-15, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7012022

RESUMO

A method is described for the preparation of protoplasts of Streptococcus mutans BHT. The muralytic enzyme mutanolysin was prepared free of contaminating proteinases and shown to completely dissolve cell walls of this strain. Whole cells were converted to stabilizable protoplasts by using the enzyme in an isotonic medium containing 40% raffinose. Experiments using [3H]thymidine and [14C]leucine as cytoplasmic pool markers revealed only minimal (10%) leakage during a 1-h incubation. Examination by electron microscopy revealed the apparent absence of structural cell wall on the enlarged spherical bodies. Quantitative chemical analyses of membranes prepared by lysing protoplasts demonstrated only very small amounts of rhamnose and trace amounts of galactose. These sugars are the principal components of the BHT cell wall polysaccharide. Also, there were only small amounts of peptidoglycan components (e.g., N-acetylglucosamine) in the purified membranes obtained by this method.


Assuntos
Endopeptidases/metabolismo , Streptococcus mutans/ultraestrutura , Membrana Celular/ultraestrutura , Parede Celular/metabolismo , Microscopia Eletrônica , Peptidoglicano/metabolismo
17.
J Clin Psychopharmacol ; 10(4): 244-51, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2286697

RESUMO

The Observer's Assessment of Alertness/Sedation (OAA/S) Scale was developed to measure the level of alertness in subjects who are sedated. This scale was tested in 18 subjects in a three-period crossover study to assess its reliability and its criterion, behavioral, and construct validity. After receiving either placebo or a titrated dose of midazolam to produce light or heavy sedation, each subject was administered two sedation scales (OAA/S Scale and a Visual Analogue Scale) and two performances tests (Digit Symbol Substitution Test and Serial Sevens Subtraction). Two raters individually evaluated the subject's level of alertness on each of the two sedation scales. The results obtained on the OAA/S Scale were reliable and valid as measured by high correlations between the two raters and high correlations between the OAA/S Scale and two of the three standard tests used in this study. The OAA/S Scale was sensitive to the level of midazolam administered; all pairwise comparisons were significant (p less than 0.05) for all three treatment levels at both test periods.


Assuntos
Nível de Alerta/efeitos dos fármacos , Atenção/efeitos dos fármacos , Midazolam/farmacologia , Testes Neuropsicológicos , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Infusões Intravenosas , Masculino , Resolução de Problemas/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos
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