Abstract
The Miniature X-ray Solar Spectrometer (MinXSS-1) CubeSat observed solar X-rays between 0.5 and 10 keV. A two-temperature, two-emission-measure model is fit to each daily averaged spectrum. ...These daily average temperatures and emission measures are plotted against the corresponding daily solar 10.7 cm radio flux (F10.7) value and a linear correlation is found between each that we call the Schwab Woods Mason (SWM) model. The linear trends show that one can estimate the solar spectrum between 0.5 and 10 keV based on the F10.7 measurement alone. The cooler temperature component of this model represents the quiescent Sun contribution to the spectra and is essentially independent of solar activity, meaning the daily average quiescent Sun is accurately described by a single temperature (1.70 MK) regardless of solar intensity and only the emission measure corresponding to this temperature needs to be adjusted for higher or lower solar intensity. The warmer temperature component is shown to represent active region contributions to the spectra and varies between 5 and 6 MK. The Geostationary Operational Environmental Satellite (GOES) XRS-B data between 1 and 8 Å is used to validate this model and it is found that the ratio between the SWM model irradiance and the GOES XRS-B irradiance is close to unity on average. MinXSS-1 spectra during quiescent solar conditions have very low counts beyond around 3 keV. The SWM model can generate MinXSS-1 or Dual Aperture X-ray Solar Spectrometer spectra at very high spectral resolution and with extended energy ranges to fill in gaps between measurements and extend predictions back to 1947.
Abstract In this study, we present the analysis of six solar flare events that occurred in 2022, using new data from the third-generation Miniature X-Ray Solar Spectrometer, also known as the ...Dual-zone Aperture X-ray Solar Spectrometer (DAXSS). The primary focus of this study is on the flare’s onset phase , which is characterized by elevated soft X-ray emissions even before the flare’s impulsive phase. We analyze the temporal evolution of plasma temperature, emission measure, and elemental abundance factors during the flare onset phase by fitting the DAXSS spectra with the Astrophysical Plasma Emission Code model. The model fitting results indicate that the flaring plasma is already at a high temperature (10–15 MK) during the onset period. The temperature rises during the onset phase, followed by a decrease and subsequent increase during the impulsive phase. Elemental abundance factors show a trend of falling below preflare values during the onset phase, with some recovery before the impulsive phase. During the impulsive phase, the abundance factors decrease from elevated coronal values to about photospheric values. We also analyze images from the 193 Å channel of the Atmospheric Imaging Assembly (AIA), highlighting the formation or brightening of coronal loop structures during the onset phase. Two distinct onset loop configurations are observed, which are referred to as one-loop and two-loop onsets. Both DAXSS and AIA observations indicate that the flare onset phase exhibits hot coronal plasma properties similar to those of the impulsive phase, suggesting that the onset phase may act as a preconditioning effect for some flares.
Abstract
The Dual-zone Aperture X-ray Solar Spectrometer (DAXSS) was flown on 2018 June 18 on the NASA 36.336 sounding rocket flight and obtained the highest resolution to date for solar soft X-ray ...(SXR) spectra over a broad energy range. This observation was during a time with quiescent (nonflaring) small active regions on the solar disk and when the 10.7 cm radio flux (F10.7) was 75 solar flux units (1 sfu = 10–22 W m
−2
Hz
−1
). The DAXSS instrument consists of a LASP-developed dual-zone aperture and a commercial X-ray spectrometer from Amptek that measures solar full-disk irradiance from 0.5 to 20 keV with a resolving power of 20 near 1 keV. This paper discusses the novel design of the spectrometer and the instrument characterization techniques. Additionally, the solar measurements obtained from the 2018 sounding rocket flight are analyzed using CHIANTI spectral models to fit the temperatures, emission measures, and relative elemental abundances of the solar corona plasma. The abundance of iron was found to be 35% higher than expected in the quiescent Sun’s corona suggesting either that our spectral models require additional sophistication or that the underlying atomic database may require updates. Future long-term systematic observations of this spectral range are needed to provide further insight into the sources of coronal heating through modeling the changes of relative elemental abundances during developments of active regions and solar flaring events.
Purpose
To provide guidelines for all surgical specialists who deal with the open abdomen (OA) or the burst abdomen (BA) in adult patients both on the methods used to close the musculofascial layers ...of the abdominal wall, and regarding possible materials to be used.
Methods
The guidelines were developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach including publications up to January 2017. When RCTs were available, outcomes of interest were quantitatively synthesized by means of a conventional meta-analysis. When only observational studies were available, a meta-analysis of proportions was done. The guidelines were written using the AGREE II instrument.
Results
For many of the Key Questions that were researched, there were no high quality studies available. While some strong recommendations could be made according to GRADE, the guidelines also contain good practice statements and clinical expertise guidance which are distinct from recommendations that have been formally categorized using GRADE.
Recommendations
When considering the OA, dynamic closure techniques should be prioritized over the use of static closure techniques (strong recommendation). However, for techniques including suture closure, mesh reinforcement, component separation techniques and skin grafting, only clinical expertise guidance was provided. Considering the BA, a clinical expertise guidance statement was advised for dynamic closure techniques. Additionally, a clinical expertise guidance statement concerning suture closure and a good practice statement concerning mesh reinforcement during fascial closure were proposed. The role of advanced techniques such as component separation or relaxing incisions is questioned. In addition, the role of the abdominal girdle seems limited to very selected patients.
CubeSat missions are flying a variety of battery technologies and range of battery capacities. As the CubeSat form factors continue to grow in size, the battery capacities will need to grow too. Thus ...maximizing battery capacity and the efficiency of battery packs are increasingly more important. To address this need for our university-built CubeSats, a new automated system used for flight testing battery cells was developed to optimize the capacity and long-term performance of a battery pack. The important steps of creating a low-cost, highly-efficient battery pack are described in detail, along with an overview of the safety acceptance testing for CubeSats deployed from the International Space Station (ISS), a location with some of the most demanding acceptance criteria, and often used as a launch platform for CubeSats. These steps include selecting the battery pack materials, developing the testing hardware and related automation software, and selecting matched battery cells for the flight battery packs. Our automation software is publicly available. The task of matching the maximum voltages and capacities of individual battery cells is an important but often time consuming process if not automated. Our battery test system autonomously charges and discharges multiple Lithium Polymer cells independently and at the same time tracks the current, voltage, and elapsed time of each cycle for capacity calculations. From these results we can combine cells to maximize the capacity for a flight battery pack. This battery test system also provides automated battery pack charge / discharge cycling to identify the battery packs with the higher efficiencies to be selected for flight. The measured state of charge curves for a battery pack, and the trending of those curves, is important for mission planning and operations. Our battery test system is low cost, and the build and test processes are easy to replicate, making it highly desirable for small spacecraft.
The Miniature X-ray Solar Spectrometer (MinXSS-1) CubeSat observed solar X-rays between 0.5 and 10 keV. A two-temperature, two-emission measure model is fit to each daily averaged spectrum. These ...daily average temperatures and emission measures are plotted against the corresponding daily solar 10.7 cm radio flux (F10.7) value and a linear correlation is found between each that we call the Schwab Woods Mason (SWM) model. The linear trends show that one can estimate the solar spectrum between 0.5 keV and 10 keV based on the F10.7 measurement alone. The cooler temperature component of this model represents the quiescent sun contribution to the spectra and is essentially independent of solar activity, meaning the daily average quiescent sun is accurately described by a single temperature (1.70 MK) regardless of solar intensity and only the emission measure corresponding to this temperature needs to be adjusted for higher or lower solar intensity. The warmer temperature component is shown to represent active region contributions to the spectra and varies between 5 MK to 6 MK. GOES XRS-B data between 1-8 Angstroms is used to validate this model and it is found that the ratio between the SWM model irradiance and the GOES XRS-B irradiance is close to unity on average. MinXSS-1 spectra during quiescent solar conditions have very low counts beyond around 3 keV. The SWM model can generate MinXSS-1 or DAXSS spectra at very high spectral resolution and with extended energy ranges to fill in gaps between measurements and extend predictions back to 1947.
The Dual-zone Aperture X-ray Solar Spectrometer (DAXSS) was flown on 2018 June18 on the NASA 36.336 sounding rocket flight and obtained the highest resolution to date for solar soft X-ray (SXR) ...spectra over a broad energy range. This observation was during a time with quiescent (non-flaring) small active regions on the solar disk and when the 10.7 cm radio flux (F10.7) was 75 solar flux units (1 sfu = 10-22 W/m^2/Hz). The DAXSS instrument consists of a LASP-developed dual-zone aperture and a commercial X-ray spectrometer from Amptek that measures solar full-disk irradiance from 0.5-20 keV with a resolving power of 20 near 1 keV. This paper discusses the novel design of the spectrometer and the instrument characterization techniques. Additionally,the solar measurements obtained from the 2018 sounding rocket flight are analyzed using CHIANTI spectral models to fit the temperatures, emission measures, and relative elemental abundances of the solar corona plasma. The abundance of iron was found to be 35 percent higher than expected in the quiescent sun's corona suggesting either that our spectral models require additional sophistication or that the underlying atomic database may require updates. Future long-term systematic observations of this spectral range are needed. DAXSS will fly on the INSPIRESat-1 CubeSat in late-2020, and its SXR spectral data could provide further insight into the sources of coronal heating through modeling the changes of relative elemental abundances during developments of active regions and solar flaring events.
Forty patients were randomly assigned to receive either the individualized learning activity packages or classroom instruction. Effectiveness was evaluated on the basis of fasting plasma glucose, ...glycosylated hemoglobin, percent of ideal body weight, and knowledge and behavior scores. No significant differences were found between the groups at entry or at the 2-month follow-up. At the 5-month follow-up, the group that received the learning activity packages scored significantly higher on knowledge assessment, significantly increased their behavior score, and decreased their percent of ideal body weight. Patients who received classroom instruction increased their behavior score and exhibited significantly decreased glycosylated hemoglobin levels. Behavior and blood glucose levels were significantly correlated. Although the learning activity packages proved effective in increasing knowledge, no significant improvement was observed in blood glucose levels
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