A wireless ECG plaster for real-time cardiac health monitoring in body sensor networks

10.1109/BioCAS.2011.61077632011 IEEE Biomedical Circuits and Systems Conference, BioCAS 2011205-20

Influence of Conduction Angles on Single Layer Switched Reluctance Machines

This paper investigates the influence of conduction angles on the performances of two 3-phase 12-slot/8-pole short pitched switched reluctance machines (SRMs): single layer SRM with conventional winding (SL-CSRM), and single layer SRM with mutually coupled winding (SL-MCSRM). Both unipolar and bipolar excitations are employed for the SRMs with different conduction angles such as unipolar 120° elec., unipolar 180° elec., bipolar 180° elec., bipolar 240° elec., and bipolar 360° elec. Their flux distributions, self- and mutual-flux linkages and inductances are analyzed, and followed by a performance comparison in terms of on-load torque, average torque, torque ripple, using two-dimensional finite element method (2D FEM). Copper loss, iron loss and machine efficiency have also been investigated with different phase currents and rotor speeds. The predicted results show that the conduction angle of unipolar 120° elec. is the best excitation approach for SL-CSRM at low current and also modest speed, as its double layer counterpart. However, at high current, the higher average torque is achieved by a conduction angle of unipolar 180° elec. For SL-MCSRM, bipolar 180° elec. conduction is the most appropriate excitation method to generate a higher average torque but lower torque ripple than others. The lower iron loss is achieved by unipolar excitation, and the SLCSRM with unipolar 120° elec. conduction produces the highest efficiency than others at 〖10A〗_rms. In addition, the performances of single layer machines have been compared with the established double layer SRMs with conventional and mutually-coupled windings. The prototype SRMs, for both SL-CSRM and SL-MCSRM, have been built and tested to validate the predictions

Combination of cyclooxygenase-2 inhibitor and doxorubicin increases the growth inhibition and apoptosis in human hepatocellular carcinoma cells

Inhibition of cyclooxygenase (COX)-2 elicits therapeutic effects in solid tumors that are coupled with the inhibition of cell proliferation and induction of apoptosis in tumor cells. Aim: This study was designed to investigate the role of COX-2 inhibitor nimesulide in cell growth and apoptosis of the cultured human hepatocellular carcinoma HepG2 cells. Methods: We performed the MTT assay, flow cytometric analysis and cell morphology study to evaluate growth inhibition and cell apoptosis upon the action of nimesulide alone or along with doxorubicin, a common agent for the treatment of human hepatocellular carcinoma. Results: Our results showed that the treatment of HepG2 cells with more than 50 µM of nimesulide suppressed COX-2 enzyme activity because of reduced PGE2 production, and then induced growth inhibition and cell apoptosis despite no alterations of COX-2 protein expression. Importantly, the combination of 50 µM or 100 µM of nimesulide and low concentrations (5 µM to 20 µM) of doxorubicin resulted in enhanced cell growth inhibition, apoptosis induction and reduced VEGF production. Conclusion: These data suggest synergistic and/or additive effects of COX-2 inhibitors and chemotherapeutic agents, and may provide the rational for clinical studies of COX-2 inhibitors on the treatment or chemoprevention of human hepatocellular carcinoma.Угнетение циклооксигеназы-2 (ЦОГ-2) оказывает терапевтический эффект при лечении больных с солидными опухолями и сопровождается снижением пролиферации опухолевых клеток и индукцией апоптоза. Цель: изучение роли ингибитора ЦОГ-2 — нимесулида в процессах роста и апоптоза культивированных клеток гепатокарциномы человека HepG2. Методы: для оценки апоптоза и угнетения роста клеток при применении нимесулида самостоятельно и в сочетании с доксорубицином применяли MTT-анализ, проточную цитометрию и стандартные морфологические методы. Результаты: установлено, что обработка клеток HepG2 cells нимесулидом в концентрации > 50 μM приводила к угнетению активности ЦОГ-2 за счет снижения продукции PGE2 , после чего отмечали подавление роста и апоптоз клеток при неизмененном уровне экспрессии ЦОГ-2. Комбинированное применение 50 μM или 100 μM нимесулида и доксорубицина в концентрации 5–20 μM обусловило усиленное угнетение роста клеток, индукции апоптоза и снижение продукции VEGF. Выводы: полученные данные свидетельствуют о синергическом и/или аддитивном эффекте при применении ингибиторов ЦОГ-2 и химиотерапевтических препаратов

Effects of dietary Aloe vera crude extracts on digestive enzyme activities and muscle proximate composition of GIFT tilapia juveniles

This study investigated the effects of dietary Aloe vera powder extract on the activities of digestive enzymes and muscle composition of Oreochromis niloticus (GIFT strain) juveniles. Five dietary groups were formulated in which A. vera powder was added into a tilapia feed at 0.5%, 1.0%, 2.0%, and 4%/kg feed, and fed for eight weeks. Amylase, trypsin, and lipase activities in the liver and along the alimentary canal (stomach, midgut, and hindgut) varied significantly between dietary groups. Amylase activity was significantly enhanced in the liver of fish fed 0.5, 1, and 2% dietary A. vera, and in the stomach of those fed 1%. Total amylase activity in the gastrointestinal tract (total gut) was significantly enhanced in fish fed 0.5% and 1% compared with control and those fed 4% dietary A. vera. Trypsin activity was significantly enhanced in the stomach of fish supplemented with 0.5% dietary A. vera and in the duodenum of those supplemented with 1%, 2%, and 4% dietary A. vera when compared with the control. Lipase activity was increased in the duodenum of fish fed 1.0% dietary A. vera when compared with the control. Muscle moisture content was significantly lower in all A. vera-supplemented fish, whereas protein was lower in those fed 2% and 4% A. vera diet when compared with the control. Based on second-order polynomial regression analysis, dietary A. vera inclusion level less than or equal to 1.76%, 1.82%, 2.10%/kg feed was determined to be suitable in enhancing carbohydrate, protein and lipid digestion, respectively, in GIFT tilapia in this study.Keywords: Aquaculture, digestion enhancers, freshwater fish, medicinal herb

Formation of the seed black holes: a role of quark nuggets?

Strange quark nuggets (SQNs) could be the relics of the cosmological QCD phase transition, and they could very likely be the candidate of cold quark matter if survived the cooling of the later Universe, although the formation and evolution of these SQNs depend on the physical state of the hot QGP (quark-gluon plasma) phase and the state of cold quark matter. We reconsider the possibility of SQNs as cold dark matter, and find that the formation of black holes in primordial halos could be significantly different from the standard scenario. In a primordial halo, the collision between gas and SQNs could be frequent enough, and thus the viscosity acting on each SQN would decrease its angular momentum and make it to sink into the center of the halo, as well as heat the gas. The SQNs with baryon numbers less than $10^{35}$ could assemble in the center of the halo before the formation of primordial stars. A black hole could form by merger of these SQNs, and then its mass could quickly become about $10^3\ M_\odot$ or higher, by accreting the surrounding SQNs or gas. The black holes formed in this way could be the seeds for the supermassive black holes at redshift as high as $z\sim 6$.Comment: 15 page

Low Mach number effect in simulation of high Mach number flow

In this note, we relate the two well-known difficulties of Godunov schemes: the carbuncle phenomena in simulating high Mach number flow, and the inaccurate pressure profile in simulating low Mach number flow. We introduced two simple low-Mach-number modifications for the classical Roe flux to decrease the difference between the acoustic and advection contributions of the numerical dissipation. While the first modification increases the local numerical dissipation, the second decreases it. The numerical tests on the double-Mach reflection problem show that both modifications eliminate the kinked Mach stem suffered by the original flux. These results suggest that, other than insufficient numerical dissipation near the shock front, the carbuncle phenomena is strongly relevant to the non-comparable acoustic and advection contributions of the numerical dissipation produced by Godunov schemes due to the low Mach number effect.Comment: 9 pages, 1 figur

Математическое моделирование явления теплообмена в условиях фазового перехода и конвекции

We present a simple and compact design for an all-solid-state laser amplifier system which can output 9.43-kHz 630-ps, 3.5-W pulse trains under 20W absorbed pumping power. The excellent matching between the repetition of its seed source and the fluorescence lifetime of the amplifying medium makes it quiet efficient for the four-pass amplifier to be pumped in cw mode without need of any synchronization device between the oscillator and the amplifier. The entire setup just covers an area of 55x25cm2. The output average power fluctuation is less than +/- 1.5% within 10min and 3% within 6h

Measurements of the observed cross sections for exclusive light hadron production in e^+e^- annihilation at \sqrt{s}= 3.773 and 3.650 GeV

By analyzing the data sets of 17.3 pb$^{-1}$ taken at $\sqrt{s}=3.773$ GeV and 6.5 pb$^{-1}$ taken at $\sqrt{s}=3.650$ GeV with the BESII detector at the BEPC collider, we have measured the observed cross sections for 12 exclusive light hadron final states produced in $e^+e^-$ annihilation at the two energy points. We have also set the upper limits on the observed cross sections and the branching fractions for $\psi(3770)$ decay to these final states at 90% C.L.Comment: 8 pages, 5 figur

Search for the Rare Decays J/Psi --> Ds- e+ nu_e, J/Psi --> D- e+ nu_e, and J/Psi --> D0bar e+ e-

We report on a search for the decays J/Psi --> Ds- e+ nu_e + c.c., J/Psi --> D- e+ nu_e + c.c., and J/Psi --> D0bar e+ e- + c.c. in a sample of 5.8 * 10^7 J/Psi events collected with the BESII detector at the BEPC. No excess of signal above background is observed, and 90% confidence level upper limits on the branching fractions are set: B(J/Psi --> Ds- e+ nu_e + c.c.)<4.8*10^-5, B(J/Psi --> D- e+ nu_e + c.c.) D0bar e+ e- + c.c.)<1.1*10^-5Comment: 10 pages, 4 figure

Measurements of psi(2S) decays to octet baryon-antibaryon pairs

With a sample of 14 million psi(2S) events collected by the BESII detector at the Beijing Electron Positron Collider (BEPC), the decay channels psi(2S)->p p-bar, Lambda Lambda-bar, Sigma0 Sigma0-bar, Xi Xi-bar are measured, and their branching ratios are determined to be (3.36+-0.09+-0.24)*10E-4, (3.39+-0.20+-0.32)*10E-4, (2.35+-0.36+-0.32)*10E-4, (3.03+-0.40+-0.32)*10E-4, respectively. In the decay psi(2S)->p p-bar, the angular distribution parameter alpha is determined to be 0.82+-0.17+-0.04.Comment: 8 pages, 8 figure