Comparative Performance of a Powerplus Vane-type Supercharger and an N.A.C.A. Roots-type Supercharger

This report presents the results of tests of a Power plus supercharger and a comparison of its performance with the performance previously obtained with an N.A.C.A. Roots-type supercharger. The Powerplus supercharger is a positive displacement blower of the vane type having mechanically operated vanes, the movement of which is controlled by slots and eccentrics. The supercharger was tested at a range of pressure differences from 0 to 15 inches of mercury and at speeds from 500 to 2,500 r.p.m. The pressure difference across the supercharger was obtained by throttling the intake of a depression tank which was interposed in the air duct between the supercharger and the Durley orifice box used for measuring the air. The results of these tests show that at low pressure differences and at all speeds the power required by the Powerplus supercharger to compress a definite quantity of air per second is considerably higher than that required by the Roots. At pressure differences from 10 to 14 inches of mercury and at speeds over 2,000 r.p.m. the power requirements of the two superchargers are practically the same. At a pressure difference of 15 inches of mercury or greater and at a speed of 2,500 r.p.m. or greater the performance of the Powerplus supercharger is slightly better than that of the Roots. Because the Powerplus supercharger cannot be operated at a speed greater than 3,000 r.p.m. as compared with 7,000 r.p.m. for the Roots, its capacity is approximately one-half that of the Roots for the same bulk. The Powerplus supercharger is more complicated and less reliable than the Roots supercharger

Universal relationship between the penetration depth and the normal-state conductivity in YBaCuO

The absolute values of the conductivity in the normal state sigma_n and of the low temperature penetration depths lambda(0) were measured for a number of different samples of the YBaCuO family. We found a striking correlation between sigma_n and 1/lambda^2, regardless of doping, oxygen reduction or defects, thus providing a simple method to predict the superconducting penetration depth and to have an estimate of the sample quality by measuring the normal-state conductivity.Comment: 7 pages, 1 figure, Europhys. Lett., accepte

Bound States and Critical Behavior of the Yukawa Potential

We investigate the bound states of the Yukawa potential $V(r)=-\lambda \exp(-\alpha r)/ r$, using different algorithms: solving the Schr\"odinger equation numerically and our Monte Carlo Hamiltonian approach. There is a critical $\alpha=\alpha_C$, above which no bound state exists. We study the relation between $\alpha_C$ and $\lambda$ for various angular momentum quantum number $l$, and find in atomic units, $\alpha_{C}(l)= \lambda [A_{1} \exp(-l/ B_{1})+ A_{2} \exp(-l/ B_{2})]$, with $A_1=1.020(18)$, $B_1=0.443(14)$, $A_2=0.170(17)$, and $B_2=2.490(180)$.Comment: 15 pages, 12 figures, 5 tables. Version to appear in Sciences in China

Pomalidomide – An Appraisal of Its Clinical Development and Role in the Treatment of Relapsed/Refractory Multiple Myeloma

Pomalidomide is a distinct immunomodulatory agent with significant activity in relapsed/refractory multiple myeloma (RRMM). The optimal treatment schedule in patients with RRMM who have received multiple lines of treatment, including bortezomib and lenalidomide, is 4 mg/day on days 1–21 of a 28-day cycle in combination with weekly low-dose dexamethasone. Improved responses and outcomes relative to traditional therapies continue to be confirmed in recently completed and ongoing trials. Pomalidomide exhibits direct tumoricidal, immunomodulatory, anti-angiogenic and anti-inflammatory activities, which facilitate combination therapy with agents with complementary mechanisms of action, resulting in greater anti-myeloma effects than single-agent therapy or previous combination therapies. For example, in combination with proteasome inhibitors and traditional chemotherapeutic agents in doublet or triplet regimens, pomalidomide provides high rates of durable response, and represents an important new treatment option for patients with RRMM requiring effective new therapies. Additionally, pomalidomide maintains its efficacy and tolerability profile in difficult-to-treat patients, including the elderly, patients with poor cytogenetics and those with renal impairment. This review summarises the clinical development of pomalidomide and discusses this effective agent for the treatment of patients with RRMM in the context of current myeloma treatment options, as well as potential future directions to further improve patient outcomes

iQuantitator: A tool for protein expression inference using iTRAQ

<p>Abstract</p> <p>Background</p> <p>Isobaric Tags for Relative and Absolute Quantitation (iTRAQ™) [Applied Biosystems] have seen increased application in differential protein expression analysis. To facilitate the growing need to analyze iTRAQ data, especially for cases involving multiple iTRAQ experiments, we have developed a modeling approach, statistical methods, and tools for estimating the relative changes in protein expression under various treatments and experimental conditions.</p> <p>Results</p> <p>This modeling approach provides a unified analysis of data from multiple iTRAQ experiments and links the observed quantity (reporter ion peak area) to the experiment design and the calculated quantity of interest (treatment-dependent protein and peptide fold change) through an additive model under log transformation. Others have demonstrated, through a case study, this modeling approach and noted the computational challenges of parameter inference in the unbalanced data set typical of multiple iTRAQ experiments. Here we present the development of an inference approach, based on hierarchical regression with batching of regression coefficients and Markov Chain Monte Carlo (MCMC) methods that overcomes some of these challenges. In addition to our discussion of the underlying method, we also present our implementation of the software, simulation results, experimental results, and sample output from the resulting analysis report.</p> <p>Conclusion</p> <p>iQuantitator's process-based modeling approach overcomes limitations in current methods and allows for application in a variety of experimental designs. Additionally, hypertext-linked documents produced by the tool aid in the interpretation and exploration of results.</p

Thomas-Fermi Calculation of the Interlayer Force in Graphite

A model of a graphite crystal is proposed in which planar layers of positive charge are considered instead of the point charges of nuclei. The interlayer electronic density is calculated integrating both the Thomas-Fermi and the Thomas-Fermi-Dirac equations. From these densities, the total energy of the electrons is calculated including corrections for inhomogeneity in the form of Weizsäcker and Kirzhnits. The influence of the different corrections is studied with the result that the best method is to calculate the density from the Thomas-Fermi-Dirac equation and to take into account the inhomogeneity corrections in the form of Kirzhnits

Lifestyle factors affecting gastroesophageal reflux disease symptoms: a cross-sectional study of healthy 19864 adults using FSSG scores

<p>Abstract</p> <p>Background</p> <p>Gastroesophageal reflux disease (GERD) is a very common disorder worldwide, comprised of reflux esophagitis (RE) and non-erosive reflux disease (NERD). As more than half of GERD patients are classified into the NERD group, precise evaluation of bothersome epigastric symptoms is essential. Nevertheless, compared with many reports targeting endoscopic reflux esophagitis, large-scale studies focusing on GERD symptoms have been very scarce.</p> <p>Methods</p> <p>To elucidate lifestyle factors affecting GERD symptoms, 19,864 healthy adults in Japan were analyzed. Sub-analyses of 371 proton pump inhibitor (PPI) users and 539 histamine H₂-receptor antagonist (H₂RA) users were also performed. Using the FSSG (Frequency Scale for the Symptoms of GERD) score as a response variable, 25 lifestyle-related factors were univariately evaluated by Student's <it>t</it>-test or Pearson's correlation coefficient, and were further analyzed with multiple linear regression modelling.</p> <p>Results</p> <p>Average FSSG scores were 4.8 ± 5.2 for total subjects, 9.0 ± 7.3 for PPI users, and 8.2 ± 6.6 for H₂RA users. Among the total population, positively correlated factors and standardized coefficients (β) for FSSG scores are inadequate sleep (β = 0.158), digestive drug users (β = 0.0972 for PPI, β = 0.0903 for H₂RA, and β = 0.104 for others), increased body weight in adulthood (β = 0.081), dinner just before bedtime (β = 0.061), the habit of midnight snack (β = 0.055), lower body mass index (β = 0.054), NSAID users (β = 0.051), female gender (β = 0.048), lack of breakfast (β = 0.045), lack of physical exercise (β = 0.035), younger age (β = 0.033), antihyperglycemic agents non-users (β = 0.026), the habit of quick eating (β = 0.025), alcohol drinking (β = 0.025), history of gastrectomy (β = 0.024), history of cardiovascular disease (β = 0.020), and smoking (β = 0.018). Positively correlated factors for PPI users are female gender (β = 0.198), inadequate sleep (β = 0.150), lack of breakfast (β = 0.146), antihypertensive agent non-users (β = 0.134), and dinner just before bedtime (β = 0.129), whereas those for H₂RA users are inadequate sleep (β = 0.248), habit of midnight snack (β = 0.160), anticoagulants non-users (β = 0.106), and antihypertensive agents non-users (β = 0.095).</p> <p>Conclusions</p> <p>Among many lifestyle-related factors correlated with GERD symptoms, poor quality of sleep and irregular dietary habits are strong risk factors for high FSSG scores. At present, usual dose of PPI or H₂RA in Japan cannot fully relieve GERD symptoms.</p