For earthquake simulations to play an important role in the reduction of seismic risk, they must be capable of high resolution and high fidelity. We have developed algorithms and tools for earthquake simulation based on multiresolution hexahedral meshes. We have used this capability to carry out 1 Hz simulations of the 1994 Northridge earthquake in the LA Basin using 100 million grid points. Our wave propagation solver sustains 1.21 teraflop/s for 4 hours on 3000 AlphaServer processors at 80% parallel efficiency. Because of uncertainties in characterizing earthquake source and basin material properties, a critical remaining challenge is to invert for source and material parameter fields for complex 3D basins from records of past earthquakes. Towards this end, we present results for material and source inversion of high-resolution models of basins undergoing antiplane motion using parallel scalable inversion algorithms that overcome many of the difficulties particular to inverse heterogeneous wave propagation problems. Abstract. For earthquake simulations to play an important role in the reduction of seismic risk, they must be capable of high resolution and high fidelity. We have developed algorithms and tools for earthquake simulation based on multiresolution hexahedral meshes. We have used this capability to carry out 1 Hz simulations of the 1994 Northridge earthquake in the LA Basin using 100 million grid points. Our wave propagation solver sustains 1.21 teraflop/s for 4 hours on 3000 AlphaServer processors at 80% parallel efficiency. Because of uncertainties in characterizing earthquake source and basin material properties, a critical remaining challenge is to invert for source and material parameter fields for complex 3D basins from records of past earthquakes. Towards this end, we present results for material and source inversion of high-resolution models of basins undergoing antiplane motion using parallel scalable inversion algorithms that overcome many of the difficulties particular to inverse heterogeneous wave propagation problems. Author(s)Volkan
The risk of cardiovascular disease is known to be increased in obstructive sleep apnea syndrome (OSAS). Its mechanism can be explained by the observation that the sympathetic tone increases due to repetitive apneas accompanied by hypoxias and arousals during sleep. Heart rate variability (HRV) representing cardiac autonomic function is mediated by respiratory sinus arrhythmia, baroreflex-related fluctuation, and thermoregulation-related fluctuation. We evaluated the heart rate variability of OSAS patients during night to assess their relationship with the severity of the symptoms. We studied overnight polysomnographies of 59 male untreated OSAS patients with moderate to severe symptoms (mean age 45.4± 11.7 yr, apnea-hypopnea index [AHI]=43.2±23.4 events per hour, and AHI >15). Moderate (mean age 47.1±9.4 yr, AHI=15-30, n=22) and severe (mean age 44.5±12.9 yr, AHI >30, n=37) OSAS patients were compared for the indices derived from time and frequency domain analysis of HRV, AHI, oxygen desaturation event index (ODI), arousal index (ArI), and sleep parameters. As a result, the severe OSAS group showed higher mean powers of total frequency (TF) (p=0.012), very low frequency (VLF) (p= 0.038), and low frequency (LF) (p=0.002) than the moderate OSAS group. The LF/HF ratio (p=0.005) was higher in the severe group compared to that of the moderate group. On the time domain analysis, the HRV triangular index (p=0.026) of severe OSAS group was significantly higher. AHI was correlated best with the LF/HF ratio (rp=0.610, p<0.001) of all the HRV indices. According to the results, the frequency domain indices tended to reveal the difference between the groups better than time domain indices. Especially the LF/HF ratio was thought to be the most useful parameter to estimate the degree of AHI in OSAS patients.
There has been considerable interest in recent years in the anti-tumor activities of flavonoids. Quercetin, a ubiquitous bioactive flavonoid, can inhibit proliferation and induce apoptosis in a variety of cancer cells. However, the precise molecular mechanism by which quercetin induces apoptosis in cancer cells is poorly understood. The present study was undertaken to examine the effect of quercetin on cell viability and to determine its underlying mechanism in human glioma cells. Quercetin resulted in loss of cell viability in a dose- and time-dependent manner and the decrease in cell viability was mainly attributed to cell death. Quercetin did not increase reactive oxygen species (ROS) generation and the quercetin-induced cell death was also not affected by antioxidants, suggesting that ROS generation is not involved in loss of cell viability. Western blot analysis showed that quercetin treatment caused rapid reduction in phosphorylation of extracellular signal-regulated kinase (ERK) and Akt. Transient transfection with constitutively active forms of MEK and Akt protected against the quercetin-induced loss of cell viability. Quercetin-induced depolarization of mitochondrial membrane potential. Caspase activity was stimulated by quercetin and caspase inhibitors prevented the quercetin-induced loss of cell viability. Quercetin resulted in a decrease in expression of survivin, antiapoptotic proteins. Taken together, these findings suggest that quercetin results in human glioma cell death through caspase-dependent mechanisms involving down-regulation of ERK, Akt, and survivin.
Background ChAdOx1 and BNT162b2 vaccines are currently commonly used against coronavirus disease 2019 worldwide. Our study was designed to determine the serostatus and relative levels of anti-S and neutralizing antibodies in patients who were administered either ChAdOx1 or BNT162b2 vaccine. In addition, we investigated whether the antibody response to each vaccine differed according to sex and age. Methods Healthcare workers (HCWs) at a general hospital who were vaccinated with two doses of either ChAdOx1 or BNT162b2 were invited to participate in this prospective cohort study. Blood samples of HCWs vaccinated with both ChAdOx1 doses over a period of 12 weeks were collected at weeks 4 and 8 post first vaccination and 2 weeks post second vaccination. Blood samples of HCWs vaccinated with BNT162b2 were collected in the third week after the first dose, and the second dose was then administered on the same day; two weeks post second dose (5 weeks after the first dose), blood samples were collected to assess the antibody response. The titers of anti-S antibodies against the severe acute respiratory syndrome coronavirus 2 spike (S) protein receptor-binding domain and the neutralizing antibodies in the collected blood were evaluated. Results Of the 309 HCWs enrolled in the study, 205 received ChAdOx1 and 104 received BNT162b2. Blood samples from participants receiving either the ChAdOx1 or BNT162b2 vaccine exhibited substantial anti-S and neutralizing antibody seropositivity subsequent to the second dose. All participants (100%) from both vaccine groups were seropositive for anti-S antibody, while 98% (201/205) of ChAdOx1-vaccinated individuals and 100% (104/104) of BNT162b2-vaccinated individuals were seropositive for neutralizing antibodies. The median levels of anti-S and neutralizing antibodies were significantly higher in the BNT162b2-vaccinated group than the ChAdOx1-vaccinated group; in particular, anti-S antibody titers of 1,020 (interquartile range, 571.0–1,631.0) U/mL vs. 2,360 (1,243–2,500) U/mL, P < 0.05, were recorded for the ChAdOx1 and BNT162b2 groups, respectively, and neutralizing antibody titers of 85.0 (65.9–92.1%) vs. 95.8 (94.4–96.6%), P < 0.05, were recorded for the ChAdOx1 and BNT162b2 groups, respectively. In the ChAdOx1 vaccine group, the neutralizing antibody level was significantly higher in women than in men (85.7 [70.3–92.5%] vs. 77.7 [59.2–91.0%], P < 0.05); however, the neutralizing antibody titer in the BNT162b2 vaccine group did not vary between the two sexes (95.9 [95.2–96.6%] vs. 95.2 [93.5–96.3%], P = 0.200). Analysis of the correlation of antibody profiles with age revealed that the levels of anti-S antibodies and signal inhibition rate (SIR) of neutralizing antibodies decreased significantly with age. Conclusion Both the ChAdOx1- and BNT162b2-vaccinated groups showed high s...
To determine predictors of neuropsychological functioning in patients with obstructive sleep apnea (OSA) and whether treatment with 2-week continuous positive airway pressure (CPAP) or supplemental oxygen would improve cognitive functioning. Design: Randomized placebo-controlled design. Setting: University-based clinical research center. Patients: Forty-six patients with untreated OSA. Interventions: Two-week CPAP, supplemental oxygen, or placebo-CPAP. Measurements and Results: Participants underwent polysomnography and completed a neuropsychological test battery before and after treatment. Prior to treatment, patients with OSA showed diffuse impairments, particularly in terms of speed of information processing, attention and working memory, executive functioning, learning and memory, as well as alertness and sustained attention. A global deficit score at baseline was positively correlated with percentage of stage 1 sleep (p = .049) only and was not correlated with obesity, daytime sleepiness, depression, fatigue, OSA severity, and the other polysomnography variables. The 3 treatment groups (therapeutic-CPAP, supplemental oxygen, and placebo-CPAP) were compared using repeated-measures analysis of variance (ANOVA). There was no significant Time x Treatment interaction for the global deficit score. When examining individual neuropsychological test scores, two thirds of them improved with time regardless of treatment, although only Digit Vigilance-Time (p = .020) showed significant improvement specific to CPAP treatment. Conclusion:The present results suggest that Digit Vigilance-Time might be the most sensitive neuropsychological test for measuring the effects of the treatments. In general, 2 weeks of CPAP or oxygen-supplementation treatment was insufficient to show overall beneficial cognitive effects, as compared with placebo-CPAP. However, 2 weeks of CPAP treatment might be helpful in terms of speed of information processing, vigilance, or sustained attention and alertness.
ObjectiveMorningness/eveningness (M/E) is a stable characteristic of individuals. Circadian rhythms are altered in episodes of mood disorder. Mood disorder patients were more evening-type than normal population. In this study, we compared the characteristics of M/E among the 257 patients with bipolar I disorder (BPD1), bipolar II disorder (BPD2) and major depressive disorder, recurrent (MDDR).MethodsM/E was evaluated using the Korean version of the composite scale of morningness (CS). Factor analysis was done to extract specific elements of circadian rhythm (morning preference, morning alertness, and evening tiredness). The total score and scores for factors and individual items of CS were compared in order to evaluate differences among the three different diagnostic groups. Factor scores of CS were different among the diagnostic groups.ResultsBPD1 subjects had a higher score for evening tiredness than BPD2 subjects (p=0.060), and BPD1 subjects had a significantly higher score for morning alertness than subjects with MDDR (p=0.034). This difference was even more profound for the representative item scores of each factor; item 2 of CS for evening tiredness (BPD1>BPD2, p=0.007) and item 5 of CS for morning alertness (BPD1>MDDR, p=0.002). Total score of CS were not different among 3 diagnostic groups.ConclusionCircadian rhythm characteristics measured by CS were different among BPD1, BPD2, and MDDR. BPD2 showed more eveningness than BPD1. MDDR showed less morningness than BPD1. CS would be a reasonable endophenotype associated with mood disorders. More studies with large sample size of mood disorders on M/E are warranted.
Figure 1: Volume visualization of simulation of earthquake-induced ground motion with 11.5 millions hexahedral elements. Left: time step 50 (actual time = 4 seconds). Right: time step 500 (actual time = 40 seconds). AbstractThis paper presents a parallel adaptive rendering algorithm and its performance for visualizing time-varying unstructured volume data generated from large-scale earthquake simulations. The objective is to visualize 3D seismic wave propagation generated from a 0.5 Hz simulation of the Northridge earthquake, which is the highest resolution volume visualization of an earthquake simulation performed to date. This scalable high-fidelity visualization solution we provide to the scientists allows them to explore in the temporal, spatial, and visualization domain of their data at high resolution. This new high resolution explorability, likely not presently available to most computational science groups, will help lead to many new insights. The performance study we have conducted on a massively parallel computer operated at the Pittsburgh Supercomputing Center helps direct our design of a simulation-time visualization strategy for the higher-resolution, 1Hz and 2 Hz, simulations.
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