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Idealized Carbon-Based Materials Exhibiting Record Deliverable Capacities for Vehicular Methane Storage
Materials
for vehicular methane storage have been extensively studied,
although no suitable material has been found. In this work, we use
molecular simulation to investigate three types of carbon-based materials,
Schwarzites, layered graphenes, and carbon nanoscrolls, for use in
vehicular methane storage under adsorption conditions of 65 bar and
298 K and desorption conditions of 5.8 bar and 358 K. Ten different
Schwarzites were tested and found to have high adsorption with maximums
at 273 VSTP/V, but middling deliverable capacities of no
more than 131 VSTP/V. Layered graphene and graphene nanoscrolls
were found to have extremely high CH4 adsorption capacities
of 355 and 339 VSTP/V, respectively, when the interlayer
distance was optimized to 11 Å. The deliverable capacities of
perfectly layered graphene and graphene nanoscrolls were also found
to be exceptional with values of 266 and 252 VSTP/V, respectively,
with optimized interlayer distances. These values make idealized graphene
and nanoscrolls the record holders for adsorption and deliverable
capacities under vehicular methane storage conditions
Distance and Percent Distance from Median BMI as Alternatives to BMI z-score
Body mass index z-score (BMIz) based on the CDC growth charts is widely used, but it is inaccurate above the 97th percentile. We explored the performance of alternative metrics based on the absolute distance or % distance of a child's BMI from the median BMI for sex and age.We used longitudinal data from 5628 children who were first examined < 12 y to compare the tracking of three BMI metrics: distance from median, % distance from median, and % distance from median on a log scale. We also explored the effects of adjusting these metrics for age differences in the distribution of BMI. The intra-class correlation coefficient (ICC) was used to compare tracking of the metrics
Prevalence and effects of emphysema in never-smokers with rheumatoid arthritis interstitial lung disease
AIMS: Autoimmune conditions such as rheumatoid arthritis-related interstitial lung disease (RA-ILD) have been linked to the existence of emphysema in never-smokers. We aimed to quantify emphysema prevalence in RA-ILD never-smokers and investigate whether combined pulmonary fibrosis and emphysema (CPFE) results in a worsened prognosis independent of baseline disease extent. METHODS: RA-ILD patients presenting to the Royal Brompton Hospital (n=90) and Asan Medical Center (n=155) had CT's evaluated for a definite usual interstitial pneumonia (UIP) pattern, and visual extents of emphysema and ILD. RESULTS: Emphysema, identified in 31/116 (27%) RA-ILD never-smokers, was associated with obstructive functional indices and conformed to a CPFE phenotype: disproportionate reduction in gas transfer (DLco), relative preservation of lung volumes. Using multivariate logistic regression, adjusted for patient age, gender and ILD extent, emphysema presence independently associated with a CT-UIP pattern in never-smokers (0.009) and smokers (0.02). On multivariate Cox analysis, following adjustment for patient age, gender, DLco, and a CT-UIP pattern, emphysema presence (representing the CPFE phenotype) independently associated with mortality in never-smokers (p=0.04) and smokers (p<0.05). CONCLUSION: 27% of RA-ILD never-smokers demonstrate emphysema on CT. Emphysema presence in never-smokers independently associates with a definite CT-UIP pattern and a worsened outcome following adjustment for baseline disease severity
Time dependence of changes of two cartilage layers in anterior cruciate ligament insertion after resection on chondrocyte apoptosis and decrease in glycosaminoglycan
<p>Abstract</p> <p>Background</p> <p>The purpose of this study is to clarify the differences in time-dependent histological changes (chondrocyte apoptosis and glycosaminoglycan (GAG) layer thickness decrease) between uncalcified fibrocartilage (UF) and calcified fibrocartilage (CF) layers at the anterior cruciate ligament (ACL) insertion after ACL resection of rabbits.</p> <p>Methods</p> <p>Forty male Japanese white rabbits underwent ACL substance resection in the right knee (resection group) and same operation without resection in the left knee (sham group). Animals were sacrificed 1, 2, 4 and 6 weeks after surgery.</p> <p>Results</p> <p>In the UF layer, the apoptosis rate in the resection group was significantly higher than that in the sham group at 1 and 2 weeks. The GAG layer thicknesses of the UF layer in the resection group at 1, 2, 4 and 6 weeks were lower than those in the sham group. In the CF layer, the apoptosis rate in the resection group was significantly higher than that in the sham group at 2 and 4 weeks. The GAG layer thickness of the CF layer in the resection group was lower than that in the sham group only at 6 weeks.</p> <p>Conclusion</p> <p>The increase in chondrocyte apoptosis rate preceded the decrease in GAG layer thickness in both layers. In the UF layer, the increase in chondrocyte apoptosis rate and the decrease in GAG layer thickness preceded those in the CF layer. Using a surviving ligament and minimizing a debridement of ACL remnant during ACL reconstruction may be important to maintain cartilage layers of ACL insertion. An injured ACL should be repaired before degenerative changes of the insertion occur.</p
Glutamatergic deficits and parvalbumin-containing inhibitory neurons in the prefrontal cortex in schizophrenia
<p>Abstract</p> <p>Background</p> <p>We have previously reported that the expression of the messenger ribonucleic acid (mRNA) for the NR2A subunit of the N-methyl-D-aspartate (NMDA) class of glutamate receptor was decreased in a subset of inhibitory interneurons in the cerebral cortex in schizophrenia. In this study, we sought to determine whether a deficit in the expression of NR2A mRNA was present in the subset of interneurons that contain the calcium buffer parvalbumin (PV) and whether this deficit was associated with a reduction in glutamatergic inputs in the prefrontal cortex (PFC) in schizophrenia.</p> <p>Methods</p> <p>We examined the expression of NR2A mRNA, labeled with a <sup>35</sup>S-tagged riboprobe, in neurons that expressed PV mRNA, visualized with a digoxigenin-labeled riboprobe via an immunoperoxidase reaction, in twenty schizophrenia and twenty matched normal control subjects. We also immunohistochemically labeled the glutamatergic axon terminals with an antibody against vGluT1.</p> <p>Results</p> <p>The density of the PV neurons that expressed NR2A mRNA was significantly decreased by 48-50% in layers 3 and 4 in the subjects with schizophrenia, but the cellular expression of NR2A mRNA in the PV neurons that exhibited a detectable level of this transcript was unchanged. In addition, the density of vGluT1-immunoreactive boutons was significantly decreased by 79% in layer 3, but was unchanged in layer 5 of the PFC in schizophrenia.</p> <p>Conclusion</p> <p>These findings suggest that glutamatergic neurotransmission via NR2A-containing NMDA receptors on PV neurons in the PFC may be deficient in schizophrenia. This may disinhibit the postsynaptic excitatory circuits, contributing to neuronal injury, aberrant information flow and PFC functional deficits in schizophrenia.</p
Dietary preference, physical activity, and cancer risk in men: national health insurance corporation study
<p>Abstract</p> <p>Background</p> <p>The effects of vegetable preference and leisure-time physical activity (LPA) on cancer have been inconsistent. We examined the effects of dietary preference and physical activity, as well as their combined effect on cancer risk.</p> <p>Methods</p> <p>This prospective cohort study included 444,963 men, older than 40 years, who participated in a national health examination program begun in 1996. Based on the answer to the question "What kind of dietary preference do you have?" we categorized dietary preference as (1) vegetables, (2) mixture of vegetables and meat, and (3) meats. We categorized LPA as low (< 4 times/wk, < 30 min/session), moderate (2–4 times/wk, ≥ 30 min/session or ≥ 5 times/wk, < 30 min/session), or high (≥ 5 times/wk, ≥ 30 min/session). We obtained cancer incidence data for 1996 through 2002 from the Korean Central Cancer Registry. We used a standard Poisson regression model with a log link function and person-time offset to estimate incidence and relative risk..</p> <p>Results</p> <p>During the 6-year follow-up period, we identified 14,109 cancer cases. Multivariate analysis revealed that a preference for vegetables or a mixture of vegetables and meat as opposed to a preference for meat played a significant protective role against lung cancer incidence (aRR, 0.81; 95% confidence interval [CI], 0.68–0.98). Compared with the low LPA group, subjects with moderate-high LPA had a significantly lower risk for stomach (aRR, 0.91; 95%CI, 0.86–0.98), lung (aRR, 0.83; 95%CI, 0.75–0.92), and liver (aRR, 0.88; 95%CI, 0.81–0.95) cancer. Among current smokers, the combined moderate-high LPA and vegetable or mixture of vegetables and meat preference group showed a 40% reduced risk of lung cancer (aRR, 0.60; 95%CI, 0.47–0.76) compared with the combined low LPA and meat preference group. Among never/former smokers, subjects with moderate-high LPA and a preference for vegetables or a mixture of vegetables and meat showed reduced stomach cancer risk (aRR, 0.72; 95%CI, 0.54–0.95).</p> <p>Conclusion</p> <p>Our findings add to the evidence of the beneficial effects of vegetable preference on lung cancer risk and of physical activity on lung, stomach, and liver cancer risk. Additionally, vegetable preference combined with LPA might significantly reduce lung and stomach cancer risk.</p
New Measurement of Parity Violation in Elastic Electron-Proton Scattering and Implications for Strange Form Factors
We have measured the parity-violating electroweak asymmetry in the elastic
scattering of polarized electrons from the proton. The result is A = -15.05 +-
0.98(stat) +- 0.56(syst) ppm at the kinematic point theta_lab = 12.3 degrees
and Q^2 = 0.477 (GeV/c)^2. The measurement implies that the value for the
strange form factor (G_E^s + 0.392 G_M^s) = 0.025 +- 0.020 +- 0.014, where the
first error is experimental and the second arises from the uncertainties in
electromagnetic form factors. This measurement is the first fixed-target parity
violation experiment that used either a `strained' GaAs photocathode to produce
highly polarized electrons or a Compton polarimeter to continuously monitor the
electron beam polarization.Comment: 8 pages, 4 figures, Tex, elsart.cls; revised version as accepted for
Phys. Lett.
Prevalence of chronic kidney disease in Thai adults: a national health survey
<p>Abstract</p> <p>Background</p> <p>The prevalence of patients with end stage renal disease (ESRD) who need dialysis and/or transplantation has more than doubled in Thailand during the past two decades. It has been suggested that therapeutic strategies to reduce the risk of ESRD and other complications in CKD are now available, thus the early recognition and the institution of proven therapeutic strategies are important and beneficial. We, therefore, aimed to determine the prevalence of CKD in Thai adults from the National Health Examination Survey of 2004.</p> <p>Methods</p> <p>Data from a nationally representative sample of 3,117 individuals aged 15 years and older was collected using questionnaires, physical examination and blood samples. Serum creatinine was measured by Jaffé method. GFR was estimated using the Chinese modified Modification of Diet in Renal Disease Study equation. Chronic kidney Disease (CKD) stages were classified based on Kidney Disease Outcome Quality Initiative (K/DOQI).</p> <p>Results</p> <p>The prevalence of CKD in Thai adults weighted to the 2004 Thai population by stage was 8.1% for stage 3, 0.2% and 0.15% for stage 4 and 5 respectively. Compared to non-CKD, individuals with CKD were older, had a higher level of cholesterol, and higher blood pressure. Those with cardiovascular risk factors were more likely to have CKD (stage 3-5) than those without, including hypertension (OR 1.6, 95%CI 1.1, 3.4), diabetes (OR 1.87, 95%CI 1.0, 3.4). CKD was more common in northeast (OR 2.1, 95%CI 1.3, 3.3) compared to central region. Urinalysis was not performed, therefore, we could not have data on CKD stage 1 and 2. We have no specific GFR formula for Thai population.</p> <p>Conclusion</p> <p>The identification of CKD patients should be evaluated and monitored for appropriate intervention for progression to kidney disease from this screening.</p
Phylogenetic position of the freshwater fish trypanosome, Trypanosoma ophiocephali (Kinetoplastida) inferred from the complete small subunit ribosomal RNA gene sequence
The complete small subunit rRNA (SSrRNA) gene sequence (2,142 nucleotides) of the freshwater fish trypanosome Trypanosoma ophiocephali Chen (1964) was determined. The phylogenetic analysis deduced using neighbor-joining, maximum parsimony, and Bayesian methods demonstrated the existence of an “aquatic clade”. T. ophiocephali was revealed to be a member of the freshwater fish trypanosomes and form the sister species with Trypanosoma siniperca and Trypanosoma sp. Carpio with high bootstrap values (98% MP, 100% NJ, 100% Bay). The high similarity of SSrRNA gene sequences and morphometric characters showed that T. ophiocephali, T. siniperca and T. sp. Carpio probably were the same species. The phylogenetic trees further suggested that Chinese freshwater fish trypanosome might be paraphyletic, and fish trypanosomes should have low host specificity
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