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The extreme miniaturization of a cold-atom interferometer accelerometer requires the development of novel technologies and architectures for the interferometer subsystems. Here, we describe several component technologies and a laser system architecture to enable a path to such miniaturization. We developed a custom, compact titanium vacuum package containing a microfabricated grating chip for a tetrahedral grating magneto-optical trap (GMOT) using a single cooling beam. In addition, we designed a multi-channel photonic-integrated-circuit-compatible laser system implemented with a single seed laser and single sideband modulators in a time-multiplexed manner, reducing the number of optical channels connected to the sensor head. In a compact sensor head containing the vacuum package, sub-Doppler cooling in the GMOT produces 15 µK temperatures, and the GMOT can operate at a 20 Hz data rate. We validated the atomic coherence with Ramsey interferometry using microwave spectroscopy, then demonstrated a light-pulse atom interferometer in a gravimeter configuration for a 10 Hz measurement data rate and T = 0-4.5 ms interrogation time, resulting in Δg/g = 2.0 × 10-6. This work represents a significant step towards deployable cold-atom inertial sensors under large amplitude motional dynamics.
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A 64-year-old female presented to the ED with severe abdominal pain. Initially it was suspected to be spontaneous aortic rupture or dissection. Contrasted CT imaging studies did not identify aneurysm and dissection, but did identify a concerning, confounding, and curious collection of fluid in the upper right quadrant. Angiography imaging was obtained and identified the origin as the collecting duct of the right kidney. The patient was admitted to the medical service. She was then evaluated by the urology service and they identified this presentation as a urinoma with extravasation of urine, in the absence of trauma or identifiable obstruction.
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We have developed a method for performing light-sheet microscopy with a single high numerical aperture lens by integrating reflective side walls into a microfluidic chip. These 45° side walls generate light-sheet illumination by reflecting a vertical light-sheet into the focal plane of the objective. Light-sheet illumination of cells loaded in the channels increases image quality in diffraction limited imaging via reduction of out-of-focus background light. Single molecule super-resolution is also improved by the decreased background resulting in better localization precision and decreased photo-bleaching, leading to more accepted localizations overall and higher quality images. Moreover, 2D and 3D single molecule super-resolution data can be acquired faster by taking advantage of the increased illumination intensities as compared to wide field, in the focused light-sheet.
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BACKGROUND: The incidence, severity, and duration of postoperative oxygen desaturation in the general surgical population are poorly characterized. We therefore used continuous pulse oximetry to quantify arterial oxygen saturation (SpO2) in a cross-section of patients having noncardiac surgery. METHODS: Oxygen saturation, blinded to clinicians, was recorded at 1-minute intervals in patients >45 years old for up to 48 hours after noncardiac surgery in 1250 patients from Cleveland Clinic Main Campus and 250 patients from the Juravinski Hospital. We determined (1) the cumulative minutes of raw minute-by-minute values below various hypoxemic thresholds; and (2) the contiguous duration of kernel-smoothed (sliding window) values below various hypoxemic thresholds. Finally, we compared our blinded continuous values with saturations recorded during routine nursing care. RESULTS: Eight hundred thirty-three patients had sufficient data for analyses. Twenty-one percent had ≥10 min/h with raw SpO2 values <90% averaged over the entire recording duration; 8% averaged ≥20 min/h <90%; and 8% averaged ≥5 min/h <85%. Prolonged hypoxemic episodes were common, with 37% of patients having at least 1 (smoothed) SpO2 <90% for an hour or more; 11% experienced at least 1 episode lasting ≥6 hours; and 3% had saturations <80% for at least 30 minutes. Clinical hypoxemia, according to nursing records, measured only in Cleveland Clinic patients (n = 594), occurred in 5% of the monitored patients. The nurses missed 90% of smoothed hypoxemic episodes in which saturation was <90% for at least one hour. CONCLUSIONS: Hypoxemia was common and prolonged in hospitalized patients recovering from noncardiac surgery. The SpO2 values recorded in medical records seriously underestimated the severity of postoperative hypoxemia.
Assuntos
Hipóxia/diagnóstico , Oximetria/tendências , Complicações Pós-Operatórias/diagnóstico , Idoso , Estudos Transversais , Feminino , Humanos , Hipóxia/sangue , Masculino , Pessoa de Meia-Idade , Oximetria/métodos , Complicações Pós-Operatórias/sangue , Estudos Prospectivos , Método Simples-CegoRESUMO
Photolithographic patterning of a xanthate precursor to poly(3,4-diphenyl-2,5-thienylene vinylene) is described. Unlike xanthate precursors to poly(p-phenylene vinylene), the thienylene vinylene analogue patterns as a positive tone resist. Characterization of irradiated films reveals photooxidative cleavage of the vinylene linker decreases the molecular weight of the polymer (increasing the solubility of the UV-exposed areas). As a result of the mechanism, the developed pattern sees no UV light exposure, which is a significant advantage compared with negative-tone-conjugated polymer resists. Single micron resolution of a low-bandgap polymer is achieved in an efficient and scalable process.
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Polímeros/química , Polivinil/química , Estrutura Molecular , Oxirredução , Processos Fotoquímicos , Raios UltravioletaRESUMO
STUDY OBJECTIVE: To evaluate the effectiveness of the CTrach Laryngeal Mask Airway (LMA) when used electively. DESIGN: Retrospective analysis. SETTING: Operating room of an academic hospital. MEASUREMENTS: Data from 126 patients who were electively intubated with the CTrach LMA over a 16-month period were reviewed. Each patient's weight, height, ASA physical status classification, Mallampati score, thyromental distance, and cervical spine range of motion were recorded. MAIN RESULTS: Successful ventilation was achieved in 100% of patients, while successful intubation was achieved in 89.7% of patients. The most common reason for failure to intubate was poor airway visualization and the inability to appropriately position the device anterior to the vocal cords. CONCLUSIONS: The major advantage of the CTrach LMA is that it is the only device that allows airway visualization during patient ventilation; however, it does not have 100% success with intubation.
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Intubação Intratraqueal/instrumentação , Máscaras Laríngeas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Vértebras Cervicais/fisiologia , Feminino , Humanos , Intubação Intratraqueal/métodos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Respiração Artificial/instrumentação , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemAssuntos
Máscaras Laríngeas , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos RetrospectivosRESUMO
A simple, direct method for photopatterning poly(p-phenylenevinylene) (PPV) from a xanthate precursor polymer is presented. The effect of UV exposure on the resultant PPV is examined by UV-Vis, XPS, FTIR, and DC conductivity measurements. By optimizing the photolithographic conditions, a spatial resolution of one micron is obtained, with minimal impact to the properties of the photopatterned PPV.