59 research outputs found
Observational study of intermittent solar jets: p-mode modulation
Aims. Recurring jets are observed in the solar atmosphere, which can erupt
intermittently. By the observation of intermittent jets, we want to understand
the causes of periodic eruption characteristics. Methods. We report
intermittent jets observed by the GST. The analysis was aided by 1400 {\AA} and
2796 {\AA} data from IRIS.These observational instruments allowed us to analyze
the temporal characteristics of jet events. Results. The jet continued for up
to 4 hours. The time distance diagram shows that the peak of the jet has
obviously periodic eruption characteristics (5 minutes) during 18:00 UT-18:50
UT. We also found periodic brightening phenomenon (5 minutes) during jets
bursts in the observed bands in the Transition Region (1400 {\AA} and 2796
{\AA}), which may be a response to intermittent jets in the upper solar
atmosphere.The time lag is 3 minutes. Evolutionary images in the TiO band
revealed the horizontal movement of granulation at the location of jet.
Compared to the quiet region of the Sun, we found that the footpoint of the jet
is enhanced at the center of the H {\alpha} spectral line profile, with no
significant changes in the line wings. This suggests the presence of prolonged
heating at the footpoint of the jet. In the mixed-polarity magnetic field
region of the jet, we observed magnetic flux emergence, cancellation, and shear
indicating possible intermittent magnetic reconnection. That is confirmed by
the NLFFF model reconstructed using the magneto-friction method. Conclusions.
The multi-wavelength analysis indicates that the events we studied were
triggered by magnetic reconnection caused by mixed-polarity magnetic fields. We
suggest that the horizontal motion of the granulation in the photosphere drives
the magnetic reconnection, which is modulated by p-mode oscillations
A Solar Eruption Driven by Rapid Sunspot Rotation
We present the observation of a major solar eruption that is associated with
fast sunspot rotation. The event includes a sigmoidal filament eruption, a
coronal mass ejection, and a GOES X2.1 flare from NOAA active region 11283. The
filament and some overlying arcades were partially rooted in a sunspot. The
sunspot rotated at 10 per hour rate during a period of 6 hours
prior to the eruption. In this period, the filament was found to rise gradually
along with the sunspot rotation. Based on the HMI observation, for an area
along the polarity inversion line underneath the filament, we found gradual
pre-eruption decreases of both the mean strength of the photospheric horizontal
field () and the mean inclination angle between the vector magnetic field
and the local radial (or vertical) direction. These observations are consistent
with the pre-eruption gradual rising of the filament-associated magnetic
structure. In addition, according to the Non-Linear Force-Free-Field
reconstruction of the coronal magnetic field, a pre-eruption magnetic flux rope
structure is found to be in alignment with the filament, and a considerable
amount of magnetic energy was transported to the corona during the period of
sunspot rotation. Our study provides evidences that in this event sunspot
rotation plays an important role in twisting, energizing, and destabilizing the
coronal filament-flux rope system, and led to the eruption. We also propose
that the pre-event evolution of may be used to discern the driving
mechanism of eruptions
Association Between Bone Mineral Density, Bone Turnover Markers, and Serum Cholesterol Levels in Type 2 Diabetes
Purpose: The association between bone mineral density (BMD), bone turnover markers, and serum cholesterol in healthy population has already been proved. However, in patients with type 2 diabetes mellitus (T2D), it has not been adequately analyzed. In this study, we investigated the correlation between BMD, bone turnover markers, and serum cholesterol levels in people with T2D.Methods: We enrolled 1,040 men and 735 women with T2D from Zhongshan Hospital between October 2009 and January 2013. Their general condition, history of diseases and medication, serum markers, and BMD data were collected. We used logistic regression analysis to identify the association between serum cholesterol levels and BMD as well as bone turnover markers.Results: In multivariate regression analysis, we observed that in men with T2D, high high-density lipoprotein-cholesterol and total cholesterol levels were significantly associated with low total lumbar, femur neck, and total hip BMD, while low-density lipoprotein-cholesterol level was only inversely associated with total lumbar and femur neck BMD. Total cholesterol and low-density lipoprotein-cholesterol levels were also negatively associated with osteocalcin, procollagen type I N-terminal propeptide, and β-crosslaps. In women with T2D, high-density lipoprotein-cholesterol level was observed to be negatively correlated with total lumbar, femur neck, and total hip BMD, while total cholesterol and low-density lipoprotein-cholesterol levels were only associated with BMD at the total lumbar. Furthermore, total cholesterol was also negatively associated with osteocalcin, procollagen type I N-terminal propeptide, and β-crosslaps; high-density lipoprotein-cholesterol was only related to osteocalcin and parathyroid hormone, while low-density lipoprotein-cholesterol was only related to β-crosslaps in women.Conclusion: Our study suggests a significantly negative correlation between serum cholesterol levels and BMD in both men and women with T2D. The associations between serum cholesterol levels and bone turnover markers were also observed in T2D patients
Development of New Microsatellite DNA Markers from Apostichopus japonicus and Their Cross-Species Application in Parastichopus parvimensis and Pathallus mollis
Twenty microsatellite DNA markers were developed for sea cucumber and used to investigate polymorphisms of 60 wild Apostichopus japonicus individuals collected from China. It revealed that all the markers were polymorphic. A total of 164 alleles were detected at 20 loci. The number of alleles per locus varied from 3 to 17 with an average of 8.2, and the expected heterozygosities of each locus ranged from 0.03 to 0.89 with an average of 0.64. Cross-species amplification was also conducted in Parastichopus parvimensis collected from the United States and Pathallus mollis collected from Peru. The result showed that 17 loci amplified Parastichopus parvimensis DNAs while only 4 loci could amplify Pathallus mollis DNAs. All of the polymorphic markers would be useful for future genetic breeding and the assessment of genetic variation within sea cucumbers
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Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
The original version of this article unfortunately contained a mistake
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