Variation comparison between the FF-distribution and the normal distribution

Let $X_{d_1,d_2}$ be an $F$-random variable with numerator and denominator degrees of freedom $d_1$ and $d_2$, respectively. We investigate the inequality: $P\{|X_{d_1,d_2}-E[X_{d_1,d_2}]|\le \sqrt{{\rm Var}(X_{d_1,d_2})}\}\ge P\{|W-E[W]|\le \sqrt{{\rm Var}(W)}\}$, where $W$ is a standard normal random variable or a $\chi^2(d_1)$ random variable. We prove that this inequality holds for $d_1\in\{1,2,3,4\}$ and $5\le d_2\in\mathbb{N}$

Ophiopogon japonicas (Linn. f.) Ker-Gawl. extract ameliorates chronic heart failure in rats

Purpose: To investigate the effect of Ophiopogon japonicas (Linn. f.) Ker-Gawl. extract (OJKE) on oxidative stress and hemodynamics in chronic congestive heart failure (CHF) rats. Methods: The rats were modelled to congestive heart failure (except normal group) , and then randomly divided into normal control group, model (untreated) group, captopril group, high-dose, middle-dose and low-dose of OJKE groups. They were treated for 4 weeks as appropriate for each group. At the end of treatment, the hemodynamic function, whole heart weight index, and blood creatinine kinase (CK), as well as superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO), nitricoxide synthase (NOS) were determined. Results: Compared with the normal control group, arterial systolic pressure (SBP), diastolic pressure (DBP), mean arterial pressure (MAP), heart rate (HR), left ventricular systolic peak (LVSP), and left ventricular pressure change rate (dp/dt max) significantly decreased (p < 0.05), while left ventricular end diastolic pressure (LVEDP), whole heart weight index, blood CK, MDA, NO, NOS significantly increased in the untreated group (p < 0.05). A high dose of OJKE significantly improved hemodynamic function, lowered MDA (8.33 ± 2.12 nmol/mL) and NO (20.58 ± 3.53 umol/L) levels (p < 0.05), and also decreased CK (0.53±0.37 U/mL) and NOS (22.46±3.29 U/mL) in CHF rats (p < 0.05). Conclusion: OJKE improved adriamycin-induced chronic congestive heart failure in rats significantly

Design and Distortion Analysis of Passive Sensor Probes for the Measurements in Electric Fields

The sensor probes deployed in the electric fields will cause the distortion in the vicinities, therefore it may significantly affect the accuracy of the measurements in the electric fields. In this paper, we propose a novel approach to separate the electric field distortion due to the spherical sensor probes in a uniform electric field. Moreover, we also investigate the impacts of the spherical sensor probes to the original electric field distortion in terms of the size of sensor probes, the electrode materials, the coupling between the polar electrodes in the design of sensor probes. Our simulation results show that a passive electric field sensor system with the bands from 5 Hz to 200 kHz, and a 20 nF capacitance, combining with our new electric field distortion correction scheme, can surprise meet the requirements of the practical engineering. Moreover, our simulation results also show that the electric field sensor probe system we suggested only has 0.16 % nonlinear errors compared with the corresponding original system measurements. We hope our work will stimulate the future research in the design of the sensor probe systems for monitoring of the electric field

Research on Overflow Monitoring Mechanism Based on Downhole Microflow Detection

The flow rate variation of the drilling fluid and micro-overflow loss is difficult to analyze. The purpose to prevent the occurrence of kick, lost circulation, and other complex conditions is not easy to be achieved. Therefore, the microflow-induced annulus multiphase flow rate and annulus pressure field model were studied, and a downhole microflow measurement system has been developed. A differential pressure type flow measurement was used in the system, and real-time downhole information was obtained to achieve deep, narrow windows and other safety-density complex formation security. This paper introduced a new bottom-hole flow meter which can measure the annular flux while drilling and monitor overflow and circulation loss. The accuracy and reliability of the MPD (managed pressure drilling) system can be improved obviously by applying the device; as a result, the safety of drilling is enhanced and the cost is reduced

Cholesteryl ester transfer protein TaqIB polymorphism and its association with serum lipid levels and longevity in Chinese Bama Zhuang population

<p>Abstract</p> <p>Background</p> <p><it>Taq</it>IB polymorphism in the cholesteryl ester transfer protein (CETP) gene has been reported to be associated with serum high-density lipoprotein cholesterol (HDL-C) levels and longevity in several populations, but controversial results also arose probably due to racial/ethnic diversity. Bama is a remote and mountainous county located in the northwest of Guangxi, People's Republic of China, which has been well known for its longevity for centuries. The current study was to investigate the possible association of CETP <it>Taq</it>IB polymorphism with serum lipid levels and longevity in the Bama Zhuang population.</p> <p>Methods</p> <p>The CETP <it>Taq</it>IB genotypes were determined by polymerase chain reaction and restriction fragment length polymorphism in 523 long-lived inhabitants (long-lived group, LG; aged 90-107 years) and 498 healthy controls without longevity family history (non-long-lived group, non-LG; aged 40-69 years) residing in Bama County.</p> <p>Results</p> <p>The levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were higher but TG, HDL-C/LDL-C ratio and the prevalence of dyslipidemia were lower in LG than in non-LG (<it>P </it>< 0.001 for all). There were no differences in the allelic and genotypic frequencies between the two groups (<it>P </it>> 0.05). Serum HDL-C levels and HDL-C/LDL-C ratio in LG were different among the genotypes (<it>P </it>< 0.01 for each), the subjects with B2B2 and B1B2 genotyes had higher HDL-C levels and HDL-C/LDL-C ratio than the subjects with B1B1genotye, whereas the levels of TC and HDL-C in non-LG were different among/between the genotypes (<it>P </it>< 0.01 for each), the B2 allele carriers had lower TC and higher HDL-C levels than the B2 allele noncarriers. Serum TG and HDL-C levels and HDL-C/LDL-C ratio were correlated with genotypes in LG, whereas serum TC and HDL-C levels were associated with genotypes in non-LG (<it>P </it>< 0.05-0.001).</p> <p>Conclusions</p> <p>The association of CETP <it>Taq</it>IB polymorphism and serum lipid profiles is different between LG and non-LG in the Chinese Bama Zhuang population. CETP <it>Taq</it>IB polymorphism might be one of the longevity-related genetic factors in this population.</p

Predictors of vessel quantitative flow ratio loss in patients with severely calcified lesions after rotational atherectomy

Background: Previous studies have established that moderately to severely calcified lesions (MSCL) are associated with high rates of major adverse cardiovascular events, even when drug-eluting stents are implanted after rotational atherectomy (RA). Yet, the changes in coronary function indexes during follow-ups have never been investigated. The quantitative flow ratio (QFR), a novel coronary function index, has been increasingly adopted in daily practice in recent years. Methods: A total of 111 MSCL patients were retrospectively enrolled in this study. The vessel QFR (QFRv) loss was defined as post-percutaneous coronary intervention QFRv minus follow-up QFRv. The study subjects were divided into high QFRv loss (n = 51) and low QFRv loss (n = 60) groups according to the binary method. The obtained predictors of QFRv loss were then analyzed. Results: The results showed that the final burr-to-vessel ratio (B to V ratio) in the high QFRv loss group decreased significantly compared to the low QFRv loss group (p &lt; 0.01). The univariate and multivariate regression analyses indicated that the final B to V ratio was an excellent predictor of QFRv loss. The cut-off value of the final B to V ratio for QFRv loss prediction was 0.50 (sensitivity: 50.98%, specificity: 68.33%, and area under the curve: 0.627 [95% confidence interval: 0.530–0.717], p &lt; 0.05). Additionally, the target vessel failure incidence in the high QFRv loss group was higher than in the low QFRv loss group (p &lt; 0.01). Conclusions: An increased burr-to-vessel ratio can prevent QFRv loss in patients with MSCLs after RA, an effect that might be closely associated with a low TVF incidence

A simulation study on the measurement of D0-D0bar mixing parameter y at BES-III

We established a method on measuring the \dzdzb mixing parameter $y$ for BESIII experiment at the BEPCII $e^+e^-$ collider. In this method, the doubly tagged $\psi(3770) \to D^0 \overline{D^0}$ events, with one $D$ decays to CP-eigenstates and the other $D$ decays semileptonically, are used to reconstruct the signals. Since this analysis requires good $e/\pi$ separation, a likelihood approach, which combines the $dE/dx$, time of flight and the electromagnetic shower detectors information, is used for particle identification. We estimate the sensitivity of the measurement of $y$ to be 0.007 based on a $20fb^{-1}$ fully simulated MC sample.Comment: 6 pages, 7 figure

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion