11,482 research outputs found

    Laboratory calibration of AAFE radiometer/scatterometer (RADSCAT)

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    A brief description of the electrical and mechanical instrument configuration, followed by an extensive discussion of laboratory tests and results are contained herein. This information is required to provide parameters for data reduction, and a basis for analysis of the measurement errors in data taken with this instrument

    Flight measurement and analysis of AAFE RADSCAT wind speed signature of the ocean

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    The advanced aerospace flight experiment radiometer scatterometer (AAFE RADSCAT) which was developed as a research tool to evaluate the use of microwave frequency remote sensors to provide wind speed information at the ocean surface is discussed. The AAFE RADSCAT helped establish the feasibility of the satellite scatterometer for measuring both wind speed and direction. The most important function of the AAFE RADSCAT was to provide a data base of ocean normalized radar cross section (NRCS) measurements as a function of surface wind vector at 13.9 GHz. The NRCS measurements over a wide parametric range of incidence angles, azimuth angles, and winds were obtained in a series of RADSCAT aircraft missions. The obtained data base was used to model the relationship between k sub u band radar signature and ocean surface wind vector. The models developed therefrom are compared with those used for inversion of the SEASAT-A satellite scatterometer (SASS) radar measurements to wind speeds

    An operational satellite scatterometer for wind vector measurements over the ocean

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    Performance requirements and design characteristics of a microwave scatterometer wind sensor for measuring surface winds over the oceans on a global basis are described. Scatterometer specifications are developed from user requirements of wind vector measurement range and accuracy, swath width, resolution cell size and measurement grid spacing. A detailed analysis is performed for a baseline fan-beam scatterometer design, and its performance capabilities for meeting the SeaSat-A user requirements. Various modes of operation are discussed which will allow the resolution of questions concerning the effects of sea state on the scatterometer wind sensing ability and to verify design boundaries of the instrument

    Kinematics of the ring-like nebula SuWt 2

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    We present the first detailed spatio-kinematical analysis and modelling of the Southern planetary nebula SuWt 2. This object presents a problem for current theories of planetary nebula formation and evolution, as it is not known to contain a central post-main sequence star. Deep narrowband [NII]6584 images reveal the presence of faint bipolar lobes emanating fromthe edges of the nebular ring. Longslit observations of the H-alpha and [NII]6584 emission lines were obtained using EMMI on the 3.6-m ESO-NTT. The spectra reveal the nebular morphology as a bright torus encircling the waist of an extended bipolar structure. By deprojection, the inclination of the ring is found to be 68\degr ±\pm 2\degr (c.f. ~90\degr for the double A-type binary believed to lie at the centre of the nebula), and the ring expansion velocity is found to be 28 km/s. Our findings are discussed with relation to possible formation scenarios for SuWt 2. Through comparison of the nebular heliocentric systemic velocity, found here to be -25 ±\pm 5 km/s, and the heliocentric systemic velocity of the double A-type binary, we conclude that neither component of the binary could have been the nebular progenitor. However, we are unable to rule out the presence of a third component to the system, which would have been the nebula progenitor.Comment: 7 pages, 4 figures. Accepted for publication in MNRA

    A Prospective Evaluation of Opioid Utilization After Upper-Extremity Surgical Procedures: Identifying Consumption Patterns and Determining Prescribing Guidelines.

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    BACKGROUND: Although adequate management of postoperative pain with oral analgesics is an important aspect of surgical procedures, inadvertent overprescribing can lead to excess availability of opioids in the community for potential diversion. The purpose of our study was to prospectively evaluate opioid consumption following outpatient upper-extremity surgical procedures to determine opioid utilization patterns and to develop prescribing guidelines. METHODS: All patients undergoing outpatient upper-extremity surgical procedures over a consecutive 6-month period had the following prospective data collected: patient demographic characteristics, surgical details, anesthesia type, and opioid prescription and consumption patterns. Analysis of variance and post hoc comparisons were performed using t tests, with the p value for multiple pairwise tests adjusted by the Bonferroni correction. RESULTS: A total of 1,416 patients with a mean age of 56 years (range, 18 to 93 years) were included in the study. Surgeons prescribed a mean total of 24 pills, and patients reported consuming a mean total of 8.1 pills, resulting in a utilization rate of 34%. Patients undergoing soft-tissue procedures reported requiring fewer opioids (5.1 pills for 2.2 days) compared with fracture surgical procedures (13.0 pills for 4.5 days) or joint procedures (14.5 pills for 5.0 days) (p \u3c 0.001). Patients who underwent wrist surgical procedures required a mean number of 7.5 pills for 3.1 days and those who underwent hand surgical procedures required a mean number of 7.7 pills for 2.9 days, compared with patients who underwent forearm or elbow surgical procedures (11.1 pills) and those who underwent upper arm or shoulder surgical procedures (22.0 pills) (p \u3c 0.01). Procedure type, anatomic location, anesthesia type, age, and type of insurance were also all significantly associated with reported opioid consumption (p \u3c 0.001). CONCLUSIONS: In this large, prospective evaluation of postoperative opioid consumption, we found that patients are being prescribed approximately 3 times greater opioid medications than needed following upper-extremity surgical procedures. We have provided general prescribing guidelines, and we recommend that surgeons carefully examine their patients\u27 opioid utilization and consider customizing their opioid prescriptions on the basis of anatomic location and procedure type to prescribe the optimal amount of opioids while avoiding dissemination of excess opioids

    Growth of Lactobacillus reuteri NCIMB 30242 during yogurt fermentation and bile salt hydrolysis activity in the product

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    International audienceAbstractThe synthesis of bile salt hydrolase has been linked to the health benefit of Lactobacillus reuteri toward lowering blood cholesterol. The aim of this study was to examine the growth and bile salt hydrolysis activity (BSHA) of L. reuteri NCIMB 30242 during milk fermentation with a yogurt starter. There was little growth of L. reuteri during a 4-h co-fermentation with a yogurt culture, and an inoculation of 4.5 × 107 CFU.mL−1 was needed to obtain the 108 CFU.mL−1 target in the product. Enrichment of milk with sugars, minerals, or peptone-based ingredients did not improve growth of L. reuteri. Viable counts of L. reuteri above 1.5 × 108 CFU.mL−1 generated texture defects. Free and microencapsulated (ME) cultures were tested for BSHA in the yogurt drinks. L. reuteri cells which grew during the 4-h lactic fermentation had 40% less BSHA than L. reuteri added directly via the commercial culture. The BSHA of free cells was apparently three times higher than in the ME culture. This study adds data showing that the yogurt production process could affect the functionality of probiotic bacteria

    Compositional Explanation of Types and Algorithmic Debugging of Type Errors

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    The type systems of most typed functional programming languages are based on the Hindley-Milner type system. A practical problem with these type systems is that it is often hard to understand why a program is not type correct or a function does not have the intended type. We suggest that at the core of this problem is the difficulty of explaining why a given expression has a certain type. The type system is not defined compositionally. We propose to explain types using a variant of the Hindley-Milner type system that defines a compositional type explanation graph of principal typings. We describe how the programmer understands types by interactive navigation through the explanation graph. Furthermore, the explanation graph can be the foundation for algorithmic debugging of type errors, that is, semi-automatic localisation of the source of a type error without even having to understand the type inference steps. We implemented a prototype of a tool to explore the usefulness of the proposed methods

    Using mlearning in the education of radiation science students

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    Radiation science is a highly visual field that is constantly evolving due to technological advances. Technology has significantly improved almost all aspects of the field over the past 10-15 years. These advances in technology have also played a significant role in the education of radiation science students didactically and clinically. The enormous increase in the capabilities of information technology provides the opportunity for educators to dramatically change their way of teaching.1 mLearning or mobile learning involves the use of mobile devices (i.e. personal digital assistants, smart phones, iPhones, iTouch, iPad, laptops and tablets) to enhance teaching and learning. The most significant advantage of mLearning is the mobility of the technology which allows for unlimited, immediate and continuous access to course materials. The goal of this initial research is to discuss the implementation of mobile learning, specifically through the use of the Apple iTouch, into the education of radiation science students
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