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1.
Appl Opt ; 59(22): G160-G166, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749329

RESUMO

We discuss the design of quantum hybrid inertial sensor that combines an optomechanical inertial sensor with the retroreflector of a cold atom interferometer. This sensor fusion approach provides absolute and high-accuracy measurements with cold atom interferometers, while utilizing the optomechanical inertial sensor at frequencies above the repetition rate of the atom interferometer. This improves the overall measurement bandwidth as well as the robustness and field deployment capabilities of these systems. We evaluate which parameters yield an optimal acceleration sensitivity, from which we anticipate a noise floor at nano-g levels from DC to 1 kHz.

2.
Nature ; 539(7627): 36-37, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27808204

Assuntos
Hidrodinâmica , Humanos
3.
Proc Natl Acad Sci U S A ; 111 Suppl 1: 4719-26, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24704880

RESUMO

After more than a decade of experiments generating and studying the physics of quantized vortices in atomic gas Bose-Einstein condensates, research is beginning to focus on the roles of vortices in quantum turbulence, as well as other measures of quantum turbulence in atomic condensates. Such research directions have the potential to uncover new insights into quantum turbulence, vortices, and superfluidity and also explore the similarities and differences between quantum and classical turbulence in entirely new settings. Here we present a critical assessment of theoretical and experimental studies in this emerging field of quantum turbulence in atomic condensates.

4.
Phys Rev Lett ; 110(10): 104501, 2013 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-23521262

RESUMO

We demonstrate an inverse energy cascade in a minimal model of forced 2D quantum vortex turbulence. We simulate the Gross-Pitaevskii equation for a moving superfluid subject to forcing by a stationary grid of obstacle potentials, and damping by a stationary thermal cloud. The forcing injects large amounts of vortex energy into the system at the scale of a few healing lengths. A regime of forcing and damping is identified where vortex energy is efficiently transported to large length scales via an inverse energy cascade associated with the growth of clusters of same-circulation vortices, a Kolmogorov scaling law in the kinetic energy spectrum over a substantial inertial range, and spectral condensation of kinetic energy at the scale of the system size. Our results provide clear evidence that the inverse energy cascade phenomenon, previously observed in a diverse range of classical systems, can also occur in quantum fluids.

5.
Cureus ; 14(11): e31565, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36540538

RESUMO

Lymphoblastic lymphoma is a rare and aggressive form of non-Hodgkin lymphoma (NHL). The tumor can derive from T-cell or B-cell and is clinically similar to acute lymphoblastic leukemia with minimal to no bone marrow involvement distinguishing the two. We present a rare case of lymphoblastic lymphoma originating from the paranasal sinuses. A 40-year-old male presented to the emergency department and was diagnosed with right-sided acute sinusitis complicated by pre-septal cellulitis. After failing medical management, he underwent endoscopic sinus surgery. Pathologic analysis of nasal contents stained for CD79a, CD34, and PAX5, suggesting a B-cell lymphoblastic lymphoma (B-LBL). He was referred to hematology-oncology and was treated with hyperfractionated cyclophosphamide, vincristine, Adriamycin, dexamethasone (Hyper-CVAD). Short-term follow-up has thus far demonstrated near-complete resolution of the tumor. Non-Hodgkin lymphomas of the paranasal sinuses are rare, and B-cell lymphoblastic lymphomas comprise just 0.3% of adults with NHL. Immunohistochemical phenotyping for B-LBL is typically positive for B-cell markers CD19, CD20, CD22 and CD79a. Classic treatment involves a chemotherapy regimen of Hyper-CVAD with an overall survival rate of 66%. B-cell lymphoblastic lymphoma is rarely reported in the paranasal sinuses. A thorough history and physical exam along with a complete workup, including biopsies with histopathological and immunohistochemical analysis, needs to be obtained. Little is known about its prognosis when the primary site is within the paranasal sinuses, and therefore, patients need prompt and aggressive treatment when the diagnosis is made.

6.
Int J Pediatr Otorhinolaryngol ; 163: 111341, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36257168

RESUMO

OBJECTIVE: Recurrent croup (RC) is a common problem in the pediatric population. We theorize that reduced rhinorrhea and post-nasal drip as well as suppressed cough receptor activity by the anticholinergic, intranasal ipratropium bromide (IB), may lead to reduced inflammation and edema of the subglottis, decreasing RC symptoms. The aim of this study is to determine the effectiveness of IB in improving symptoms of RC and in reducing the need for alternative forms of management. METHOD: A retrospective chart review combined with survey data of patients with RC was conducted to assess demographic data, comorbidities, and treatment outcomes. Pediatric patients less than 10 years of age diagnosed with RC through the department of pediatric otolaryngology between 2018 and 2020 were included. Results were compared between one group treated with IB for RC and a second group treated with medications other than IB. RESULTS: Among the 67 patients treated for RC, 34 completed survey data and were included in the study. Overall, patients who were treated with IB for RC had 1.83 less croup episodes per year (p = 0.046), a 0.5-point improvement in child symptoms (p = 0.017) and 1.3 fewer doses of steroids per year than the patients not treated with IB (p = 0.018). Patients treated with IB were significantly more likely to answer "yes," that the use of medication helped improve symptoms (p < 0.01). CONCLUSION: Intranasal IB is a novel therapeutic option that may reduce RC events, improve patient symptoms and reduce steroid use. Further prospective studies are needed to definitively characterize the benefits of IB in the treatment of RC.


Assuntos
Crupe , Ipratrópio , Humanos , Criança , Ipratrópio/uso terapêutico , Crupe/tratamento farmacológico , Estudos Retrospectivos , Administração Intranasal , Antagonistas Colinérgicos
7.
Laryngoscope ; 132(3): 662-667, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34633085

RESUMO

OBJECTIVES: Venous thromboembolism (VTE) is a major cause of morbidity and mortality for surgical patients. This article aims to determine factors that may have contributed to the development of VTE in patients undergoing lateral skull base surgery, to assess the validity of the Caprini Risk Assessment Model (RAM) score in this subset of patients, and to determine the efficacy of mechanical DVT prophylaxis alone in preventing VTE. STUDY DESIGN: Retrospective chart review. METHODS: A retrospective chart review was conducted of patients who underwent skull base surgery for vestibular schwannoma, and the rate of VTE was assessed. Patient demographics, comorbidities, and treatment factors were examined to determine risk factors associated with the development of a postoperative thrombotic event. Caprini RAM scores were compared for patients who developed a VTE. RESULTS: Among 197 patients, the rate of VTE formation was 3.5%. No individual risk factor independently contributed to the development of a thrombotic event. The mean Caprini RAM score was 4.06 in patients who did not develop a VTE and 5.14 in the patients that did develop a VTE (P = .005). The Caprini score was significant for the risk of VTE formation, with an odds ratio of 2.8 (P = .009, 95% CI = 1.3-6.2). CONCLUSION: Venous thromboembolism rates are relatively low following lateral skull base surgery. While there is no individual risk factor associated with increased VTE risk, the Caprini RAM score appears to be a useful predictor of risk. The Caprini score may be useful in identifying high-risk patients who may benefit from chemoprophylaxis for VTE prevention. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:662-667, 2022.


Assuntos
Base do Crânio/cirurgia , Tromboembolia Venosa/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Craniotomia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/cirurgia , Estudos Retrospectivos , Fatores de Risco , Tromboembolia Venosa/epidemiologia , Adulto Jovem
8.
Toxicology ; 176(1-2): 25-37, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12062927

RESUMO

Bromodichloromethane (BDCM) is a drinking water disinfectant by-product that has been implicated in liver, kidney and intestinal cancers in rodents and in intestinal tumors and low birth weight effects in humans. BDCM is also hepatotoxic and requires metabolic activation for both toxicity and carcinogenicity. We have recently reported that CYP1A2 may participate in that metabolism and we now report experiments to support that implication. Induction of CYP1A2 in male F344 rats without inducing CYP2E1 or CYP2B1/2, using TCDD, increased the hepatotoxicity of BDCM when compared to earlier work conducted under similar protocols. Inhibition of CYP1A2, with isosafrole, reduced the metabolism and toxicity of BDCM in the previously induced rats. In addition, specific activities and Western blots for these CYP isoenzymes were measured 24 h after exposure. Activity data show that only CYP1A2 was inhibited by isosafrole; isosafrole forms a complex with CYP1A2 that persists for more than 24 h. Western blot results generally agree with the activity data except that isosafrole induced the protein for all isoenzymes measured. A physiologically based pharmacokinetic model, developed previously, estimated that BDCM metabolism was complete about 7 h after gavage dosing. It is noteworthy that the reduction in CYP1A2 activity was still measurable despite the production of additional CYP1A2 protein during the period of approximately 18 h after BDCM metabolism was complete. These results demonstrate that CYP1A2 does metabolize BDCM and does contribute to hepatotoxicity under certain conditions.


Assuntos
Carcinógenos/metabolismo , Citocromo P-450 CYP1A2/biossíntese , Fígado/enzimologia , Trialometanos/metabolismo , Alanina Transaminase/sangue , Animais , Western Blotting , Brometos/sangue , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Indução Enzimática , Isoenzimas/biossíntese , L-Iditol 2-Desidrogenase/sangue , Fígado/efeitos dos fármacos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Modelos Biológicos , Dibenzodioxinas Policloradas/farmacologia , Ratos , Ratos Endogâmicos F344 , Safrol/farmacologia
9.
Phys Rev Lett ; 98(11): 110402, 2007 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-17501028

RESUMO

We report observations of vortex formation by merging and interfering multiple (87)Rb Bose-Einstein condensates (BECs) in a confining potential. In this experiment, a single harmonic potential well is partitioned into three sections by a barrier, enabling the simultaneous formation of three independent, uncorrelated BECs. The BECs may either automatically merge together during their growth, or for high-energy barriers, the BECs can be merged together by barrier removal after their formation. Either process may instigate vortex formation in the resulting BEC, depending on the initially indeterminate relative phases of the condensates and the merging rate.

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