Mewaldt et al. (2012) fitted the observations of the ground level enhancement (GLE) events during solar cycle 23 to the double power law equation to obtain the four spectral parameters, the ...normalization constant C, low‐energy power law slope γ1, high‐energy power law slope γ2, and break energy E0. There are 16 GLEs from which we select 13 for study by excluding some events with complicated situation. We analyze the four parameters with conditions of the corresponding solar events. According to solar event conditions, we divide the GLEs into two groups, one with strong acceleration by interplanetary shocks and another one without strong acceleration. By fitting the four parameters with solar event conditions we obtain models of the parameters for the two groups of GLEs separately. Therefore, we establish a model of energy spectrum of solar cycle 23 GLEs, which may be used in prediction in the future.
Key Points
GLE energy spectrum parameters are studied with conditions of the corresponding solar events
Solar conditions are used to determine whether there is strong interplanetary shock acceleration
Preliminary prediction model of energy spectrum of ground level enhancement events is established
Summary
Background
The pathophysiology of lymphoedema is poorly understood. Current treatment options include compression therapy, resection, liposuction and lymphatic microsurgery, but determining ...the optimal treatment approach for each patient remains challenging.
Objectives
We characterized skin and adipose tissue alterations in the setting of secondary lymphoedema.
Methods
Morphological and histopathological evaluations were conducted for 70 specimens collected from 26 female patients with lower‐extremity secondary lymphoedema following surgical intervention for gynaecological cancers. Indocyanine green lymphography was performed for each patient to assess lymphoedema severity.
Results
Macroscopic and ultrasound findings revealed that lymphoedema adipose tissue had larger lobules of adipose tissue, with these lobules surrounded by thick collagen fibres and interstitial lymphatic fluid. In lymphoedema specimens, adipocytes displayed hypertrophic changes and more collagen fibre deposits when examined using electron microscopy, whole‐mount staining and immunohistochemistry. The number of capillary lymphatic channels was also found to be increased in the dermis of lymphoedema limbs. Crown‐like structures (dead adipocytes surrounded by M1 macrophages) were less frequently seen in lymphoedema samples. Flow cytometry revealed that, among the cellular components of adipose tissue, adipose‐derived stem/stromal cells and M2 macrophages were decreased in number in lymphoedema adipose tissue compared with normal controls.
Conclusions
These findings suggest that long‐term lymphatic volume overload can induce chronic tissue inflammation, progressive fibrosis, impaired homeostasis, altered remodelling of adipose tissue, impaired regenerative capacity and immunological dysfunction. Further elucidation of the pathophysiological mechanisms underlying lymphoedema will lead to more reliable therapeutic strategies.
What's already known about this topic?
The pathophysiology of lymphoedema is poorly understood.
Determining the optimal treatment approach for each patient remains challenging.
What does this study add?
The present study characterizes various pathological changes in lymphoedema adipose tissue such as chronic inflammation, progressive fibrosis, impaired homeostasis and remodelling of adipose tissue and immunological dysfunction.
What is the translational message?
Understanding the mechanisms underlying lymphoedema will lead to more reliable therapeutic strategies.
Plain language summary available online
Objective
Advanced parental age has raised additional concern as a risk factor of autism. We conducted a meta‐analysis of observational studies investigating the association between advanced parental ...age and risk of autism.
Method
PubMed, EMBASE, and Web of Science were searched for reports published up to November 11, 2015. Risk estimates from individual studies were pooled using random‐effects models.
Results
Twenty‐seven studies were included in the meta‐analysis. Compared with the reference points, the lowest parental age category was associated with a reduced risk of autism in the offspring, with adjusted odds ratios (ORs) 0.89 (95% confidence intervals CIs 0.75–1.06) and 0.81 (95% CI 0.73–0.89) for mother and father, respectively, and the highest parental age category was associated with an increased risk of autism in the offspring, with adjusted ORs 1.41 (95% CI 1.29–1.55) and 1.55 (95% CI 1.39–1.73) for mother and father respectively. Dose–response meta‐analysis indicated that an increase of 10 years in maternal and paternal age was associated with an 18% and 21% higher risk of autism.
Conclusion
Advanced parental age was associated with an increased risk of autism in the offspring. More mechanistic studies are needed to further explain this positive association.
We report on nano-infrared (IR) imaging studies of confined plasmon modes inside patterned graphene nanoribbons (GNRs) fabricated with high-quality chemical-vapor-deposited (CVD) graphene on Al2O3 ...substrates. The confined geometry of these ribbons leads to distinct mode patterns and strong field enhancement, both of which evolve systematically with the ribbon width. In addition, spectroscopic nanoimaging in the mid-infrared range 850–1450 cm–1 allowed us to evaluate the effect of the substrate phonons on the plasmon damping. Furthermore, we observed edge plasmons: peculiar one-dimensional modes propagating strictly along the edges of our patterned graphene nanostructures.
Solar eruptions are well-recognized as major drivers of space weather but what causes them remains an open question. Here we show how an eruption is initiated in a non-potential magnetic ...flux-emerging region using magnetohydrodynamic modelling driven directly by solar magnetograms. Our model simulates the coronal magnetic field following a long-duration quasi-static evolution to its fast eruption. The field morphology resembles a set of extreme ultraviolet images for the whole process. Study of the magnetic field suggests that in this event, the key transition from the pre-eruptive to eruptive state is due to the establishment of a positive feedback between the upward expansion of internal stressed magnetic arcades of new emergence and an external magnetic reconnection which triggers the eruption. Such a nearly realistic simulation of a solar eruption from origin to onset can provide important insight into its cause, and also has the potential for improving space weather modelling.
Accumulating evidence has revealed that dental anxiety (DA), as a dispositional factor toward the dental situation, is associated with the state anxiety (SA) and pain related to dental procedures. ...However, conclusions from individual studies may be limited by the treatment procedures that patients received, the tools used to assess DA, or the treatment stages when anxiety or pain was assessed. It is unclear whether DA, at the study level, accounts for the variance in pretreatment SA. The impact of DA and SA on pain at different treatment stages has not been systematically investigated. To address these questions, we present novel meta-analytical evidence from 35 articles (encompassing 47 clinical groups) that investigated DA in a clinical group. Subgroup analyses revealed that the studies of surgical and nonsurgical procedures did not significantly differ in either DA or pretreatment SA. Furthermore, metaregressions revealed DA as a significant predictor that explained the variance in SA assessed before and during treatment but not after treatment. The findings suggest that patient DA has a significant impact on patient SA. Metaregressions revealed DA as a significant predictor that explained the variance in expected pain, pain during treatment and posttreatment pain. In contrast, pretreatment SA was a significant predictor that explained the variance in expected pain. The findings reveal that DA has a consistent impact on pain through the entire period of dental treatment. Altogether, the findings highlight the role of DA as an overall indicator for anxiety and pain, across different types of dental procedures or treatment stages. We conclude that anxiety should be assessed as a critical step not only in anxiety management for high-DA patients, but also in pain control for all dental patients.
Bronchopulmonary dysplasia (BPD) is an important complication of mechanical ventilation in preterm infants, and no definite therapy can eliminate this complication. Pulmonary inflammation plays a ...crucial role in its pathogenesis, and glucocorticoid is one potential therapy to prevent BPD.
To compare the effect of intratracheal administration of surfactant/budesonide with that of surfactant alone on the incidence of death or BPD.
A clinical trial was conducted in three tertiary neonatal centers in the United States and Taiwan, in which 265 very-low-birth-weight infants with severe respiratory distress syndrome who required mechanical ventilation and inspired oxygen (fraction of inspired oxygen, ≥50%) within 4 hours of birth were randomly assigned to one of two groups (131 intervention and 134 control). The intervention infants received surfactant (100 mg/kg) and budesonide (0.25 mg/kg), and the control infants received surfactant only (100 mg/kg), until each infant required inspired O2 at less than 30% or was extubated.
The intervention group had a significantly lower incidence of BPD or death (55 of 131 42.0% vs. 89 of 134 66%; risk ratio, 0.58; 95% confidence interval, 0.44-0.77; P < 0.001; number needed to treat, 4.1; 95% confidence interval, 2.8-7.8). The intervention group required significantly fewer doses of surfactant than did the control group. The intervention group had significantly lower interleukin levels (IL-1, IL-6, IL-8) in tracheal aspirates at 12 hours and lower IL-8 at 3-5 and 7-8 days.
In very-low-birth-weight infants with severe respiratory distress syndrome, intratracheal administration of surfactant/budesonide compared with surfactant alone significantly decreased the incidence of BPD or death without immediate adverse effect. Clinical trial registered with www.clinicaltrials.gov (NCT-00883532).
The survey description and the near-, mid-, and far-infrared flux properties are presented for the 258 galaxies in the Local Volume Legacy (LVL). LVL is a Spitzer Space Telescope legacy program that ...surveys the local universe out to 11 Mpc, built upon a foundation of ultraviolet, H Delta *a, and Hubble Space Telescope imaging from 11HUGS (11 Mpc H Delta *a and Ultraviolet Galaxy Survey) and ANGST (ACS Nearby Galaxy Survey Treasury). LVL covers an unbiased, representative, and statistically robust sample of nearby star-forming galaxies, exploiting the highest extragalactic spatial resolution achievable with Spitzer. As a result of its approximately volume-limited nature, LVL augments previous Spitzer observations of present-day galaxies with improved sampling of the low-luminosity galaxy population. The collection of LVL galaxies shows a large spread in mid-infrared colors, likely due to the conspicuous deficiency of 8 Delta *mm polycyclic aromatic hydrocarbon emission from low-metallicity, low-luminosity galaxies. Conversely, the far-infrared emission tightly tracks the total infrared emission, with a dispersion in their flux ratio of only 0.1 dex. In terms of the relation between the infrared-to-ultraviolet ratio and the ultraviolet spectral slope, the LVL sample shows redder colors and/or lower infrared-to-ultraviolet ratios than starburst galaxies, suggesting that reprocessing by dust is less important in the lower mass systems that dominate the LVL sample. Comparisons with theoretical models suggest that the amplitude of deviations from the relation found for starburst galaxies correlates with the age of the stellar populations that dominate the ultraviolet/optical luminosities.
Objectives
To investigate the discriminative ability and diagnostic accuracy of the Timed Up and Go Test (TUG) as a clinical screening instrument for identifying older people at risk of falling.
...Design
Systematic literature review and meta‐analysis.
Setting and Participants
People aged 60 and older living independently or in institutional settings.
Measurements
Studies were identified with searches of the PubMed, EMBASE, CINAHL, and Cochrane CENTRAL data bases. Retrospective and prospective cohort studies comparing times to complete any version of the TUG of fallers and non‐fallers were included.
Results
Fifty‐three studies with 12,832 participants met the inclusion criteria. The pooled mean difference between fallers and non‐fallers depended on the functional status of the cohort investigated: 0.63 seconds (95% confidence (CI) = 0.14–1.12 seconds) for high‐functioning to 3.59 seconds (95% CI = 2.18–4.99 seconds) for those in institutional settings. The majority of studies did not retain TUG scores in multivariate analysis. Derived cut‐points varied greatly between studies, and with the exception of a few small studies, diagnostic accuracy was poor to moderate.
Conclusion
The findings suggest that the TUG is not useful for discriminating fallers from non‐fallers in healthy, high‐functioning older people but is of more value in less‐healthy, lower‐functioning older people. Overall, the predictive ability and diagnostic accuracy of the TUG are at best moderate. No cut‐point can be recommended. Quick, multifactorial fall risk screens should be considered to provide additional information for identifying older people at risk of falls.
Scaling laws for the additive manufacturing Rubenchik, Alexander M.; King, Wayne E.; Wu, Sheldon S.
Journal of materials processing technology,
07/2018, Volume:
257
Journal Article
Peer reviewed
Open access
The evaluation of simple thermal model of selective laser melting (SLM) process shows that the temperature distribution in the sample is characterized by two dimensionless parameters: normalized ...enthalpy and the ratio of dwell time to the thermal diffusion time. We demonstrated that the melt depth data taken for different machines for different materials collapsed in one curve, making possible to rescale the optimal processing parameters between the different materials and machines. The melt pool depth, width and the length are the universal function of these two parameters. Within the operational range of parameters for SLM these functions can be interpolated by the simple algebraic expressions given the possibility to reduce the calculation of the melt pool characteristic to spreadsheet model.
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