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Modeling of a drill-string acoustic channel has been an important topic in downhole telemetry for a long time. The propagation of drill-string guided waves in the borehole contains excitation, attenuation, and mode conversion issues that have not been considered by existing modeling methods. In this article, we formulate a hybrid modeling method to investigate the response characteristics of a fundamental-mode drill-string wave in various borehole environments. This hybrid method provides channel functions, including transmitting and receiving deployments, periodicity of the structure, and formation property changes. The essential physics of the drill-string wave propagation is captured with a one-dimensional model. The analytical solutions of the wavefield in multilayered cylindrical structures are introduced into a propagation matrix to express drill-string-wave interactions with the borehole environments. The effectiveness of the proposed method is confirmed through comparison with the finite-difference method. In addition, by designing numerical models, we investigate the conversion effect of the drill-string wave at the tool joint. We demonstrate that the conversion intensity of the drill-string wave is positively correlated not only with the cross-sectional area of the tool joint but also with the wave impedance of the outer formation. Hard formation outside the borehole reduces the energy leakage while intensifying the conversion of drill-string waves to Stoneley waves, and the opposite is true for the drill string in an infinite fluid. The converted Stoneley waves interfere with the drill-string waves, resulting in variations of bandgap distribution, which challenges the reliability of the data transmission.

High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner. Sound speed mapping of brain tissues provides unique information for such a purpose. In addition, it is particularly important for building digital human acoustic models, which form a reference for future ultrasound research. Conventional ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft tissue. We carry out numerical experiments to demonstrate that the time-domain waveform inversion technique, originating from the geophysics community, is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound signals. The successful implementation of such an approach to brain imaging requires the following items: signals of sub-megahertz frequencies transmitting across the inside of skull, an accurate numerical wave equation solver simulating the wave propagation, and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization theory. Here we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution, by evaluating the similarity between synthetic data and observed data through using limited length Wiener filter. We implement the proposed approach to iteratively update the parametric models of the human brain. The quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases, in a potentially more portable, more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography.

Total flavonoid tablet from Anemarrhenae Rhizoma (Zhimu tablet), which was made of total polyphenol components extracted from the dried rhizome of Anemarrhena asphodeloides Bge. (Zhimu in Chinese), is a novel traditional Chinese medicine prescribed for the treatment of diabetes. Mangiferin (MF) and neomangiferin (NMF) are the two main components detected and determined in Zhimu tablet, accounting for 8.9% of the total weight of each tablet. In the present study, high performance liquid chromatography (HPLC) coupled with time-of-flight (TOF) tandem mass spectrometry (MS) was applied to characterize the metabolites of MF and NMF in rat plasmas collected at different time points after oral administration of Zhimu tablet at a dose of 3.63g/kg (corresponding to 270mg/kg MF). Accurate mass measurement was used to determine the elemental composition of metabolites and thus to confirm the proposed structures of identified metabolites. Time points of appearance of some metabolites, such as isomers, were also taken into account during the structure confirmation. A total of 21 potential metabolites were found in rat plasma at different time points, and the metabolic pathways in vivo were involved in hydrolysis, methylation, glucuronide conjugation, glycoside conjugation, sulphation, dehydration and isomerisation. Furthermore, a selective and accurate LC-MS assay method was developed and validated for the quantification of MF in plasma. Semi-quantification of main conjugated metabolites was also performed in order to describe the dynamic metabolism profiles of polyphenol components in Zhimu tablet. MF concentration in plasma reached 1.36±0.47μgmL(-1) about 5.0h after oral administration of Zhimu tablet, which showed a 3.24- and 4.91-fold increase in plasma maximum concentration and area under the concentration-time curve (AUC) from 0 to 24h of MF compared with those for rats administered with free MF, respectively. The results indicated that the pharmacokinetic processes and bioavailability of MF in rats would be affected by other components in Zhimu tablet.

The complete form of the vertical vorticity tendency equation (the complete-form vorticity equation) is derived from the Ertel potential vorticity equation to contain thermodynamic factors. In this study, a new complete-form vorticity equation, which has the same form as the original complete-form vorticity equation, is deduced from the absolute vorticity vector equation combined with the continuity equation and the expression of three-dimensional (3D) entropy gradient. By comparing the complete-form vorticity equation with the classical vertical vorticity equation, it is found that regardless of whether or not the isentropic surface is tilting, the two vorticity equations are in essence the same. The “baroclinic term” of the complete-form vorticity equation is exactly equal to the solenoidal term of the classical one, and there is a significant amount of cancellation between the two baroclinic items (the “slantwise term” and the horizontal vorticity change term) in the complete-form vorticity equation. In operational weather analysis, the tilt of the isentropic surface can be diagnosed according to the density of the isotherm on the upper-level isobaric map. For synoptic-scale motion, the vertical vorticity produced by the tilt of the isentropic surface is due to the contribution of atmospheric baroclinicity, which is measured by the solenoid. The 3D solenoid is parallel to the isentropic surface, so the more tilted the isentropic surface, the bigger the projection of the 3D solenoid in the vertical direction. The baroclinic contribution can be interpreted based on the PV thinking theory, but the relationship between the vorticity field and the potential vorticity field is not immediate.

Based on stability theory, a class of neural network controller design of uncertain nonlinear time-delay systems is studied. Using the ability that neural network can approximate any nonlinear function, a kind of weights correction law based on radial basis function (RBF) neural network (NN) and the adaptive controller design scheme are proposed. According to Lyapunov stability analysis method, this paper gives the sufficient conditions that neural network controller can make this kind of uncertain nonlinear time-delay systems stable in the sense of Lyapunov. At last, the proposed neural network controller is verified to be correct and effective by the simulation examples.

With rapid economic and social development in Tianjin coastal area, environmental impact factors are increasingly complex. In order to study the relationships between macrobenthos and environmental variables, macrobenthos and seven environmental variables (including dissolved oxygen, active phosphate, inorganic nitrogen, ammonia, nitrate, nitrite, and oil) are investigated in the summer of 2004 and 2007. Canonical Correspondence Analysis (CCA) and Redundancy Analysis (RDA) in CANOCO software are all employed in the analysis for mutual authentication of the result. The results indicate that: (1) reactive phosphate and nitrite are the most important impact factor for the macrobenthic community; (2) nitrate is the supplementary factor that explains the macrobenthos data; (3) whether inorganic nitrogen is a key impact factor, it needs further research.

With development of the mobile technology, the quantity of the mobile application is also growing, and how to ensure the quality of the application has become a hot topic. Android is open platform for mobile devices, more and more developers like to develop application based on the Android system, which makes the quantity of the Android application is growing .This paper introduces the automatic testing of Android with Android Uiautomator, and describes the process of automatic test. The test result is analyzed, and the advantages of Android application system are described.

Q-vector is an important physical quantity in diagnosing the vertical velocity based on the quasi-geostrophic ω-equation. Generally, Q-vector and its extension expressions, such as the semi-geostrophic-, ageostrophic- and moist Q-vectors, can be derived from the primitive equation set on the approximated f-plane. However, the atmospheric quasi-geostropic feature can not be considered in the traditional method. In this paper, the Q-vector and its extension expressions were derived from the quasi-geostrophic ω-equation directly in terms of the mathematical-physical transformation. Then, the deficiency of the traditional Q-vector derivation in physics was discussed.

The second mitochondria‑derived activator of caspases (Smac), an antagonist of the inhibitor of apoptosis protein (IAP), increases chemosensitivity in vitro. Survivin, an IAP family member, mediates cancer cell survival and chemoresistance. The present study investigated the correlation between Smac and survivin expression in primary breast cancer, and the sensitivity to anthracycline during neoadjuvant chemotherapy (NAC). Pre‑treatment biopsies and post‑anthracycline treatment tumor sections were analyzed from 98 cases. Biomarker expression was evaluated by immunohistochemistry in tumor samples from clinical stage II and III anthracycline‑based NAC‑treated breast cancer. A univariate analysis indicated that the estrogen receptor (ER), Smac and survivin were significantly predictive of a pathological complete response (pCR) (P=0.004, 0.001 and 0.037, respectively) in pre‑chemotherapy samples. ER, Smac and survivin expression was also significant for pCR on the multivariate analysis (P=0.001, 0.031 and 0.012, respectively). An inverse association was identified between survivin and Smac expression (r=‑0.217, P=0.032; and r=‑0.335, P=0.003, respectively) prior to and following NAC. The patients with low survivin expression or high Smac expression had significantly longer disease‑free survival (DFS; P=0.012 and P=0.020, respectively) and overall survival (OS; P=0.01 and P=0.033, respectively) compared with the patients with high survivin or low Smac expression. Cox regression analyses demonstrated that survivin, Smac and clinical stage were independent predictors for DFS and OS. The present study indicated the significance of Smac and survivin in determining the breast cancer response to anthracycline‑based chemotherapy, and may permit further stratifying of pre‑chemotherapy patients to undertake more tailored treatments.

Hyperlipidemia is an important complication of kidney transplantation affecting up to 74% of recipients. HMG-CoA reductase inhibitors are reported to provide safe and effective treatment for this problem. A recent study suggests that pravastatin, an HMG-CoA reductase inhibitor, also decreases the incidence of both clinically severe acute rejection episodes and natural killer cell cytotoxicity after orthotopic heart transplantation. We have performed a prospective randomized pilot study of the effect of pravastatin on these same parameters after cadaveric kidney transplantation. Graft recipients were randomized to receive pravastatin after transplantation or no pravastatin (24 patients in each group) in addition to routine cyclosporine and prednisone immunosuppression. Lipid levels, acute rejection episodes and serial natural killer cell cytotoxicities were followed for 4 months after the transplant. At the end of the study period, pravastatin had successfully controlled mean total cholesterol levels (202.6 +/- 9.3 vs. 236.5 +/- 11.9 mg/dl, P < 0.02), LDL levels (107.9 +/- 6.6 vs.149.6 +/- 10.7 mg/dl, P < 0.002), and triglyceride levels (118.8 +/- 14.2 vs. 157.2 +/- 13.8 mg/dl, P < 0.05). In addition, the pravastatin-treated group experienced a reduction in the incidence of biopsy-proven acute rejection episodes (25% vs. 58%, P = 0.01), the incidence of multiple rejections episodes (P < 0.05), and the use of both pulse methylprednisolone (P = 0.01) and OKT3 (P = 0.02). Mean natural killer cell cytotoxicity was similarly reduced (11.3 +/- 1.6 vs. 20.0 +/- 2.0% lysis of K562 target cells, P < 0.002). These data suggest that pravastatin exerts an additional immunosuppressive effect in kidney transplant recipients treated with cyclosporine-based immunosuppression.

Hypercholesterolemia is common after cardiac transplantation and may contribute to the development of coronary vasculopathy. Pravastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has been shown to be effective and safe in lowering cholesterol levels after cardiac transplantation. Cell-culture studies using inhibitors of HMG-CoA reductase have suggested an immunosuppressive effect.Early after transplantation, we randomly assigned consecutive patients to receive either pravastatin (47 patients) or no HMG-CoA reductase inhibitor (50 patients).Twelve months after transplantation, the pravastatin group had lower mean (+/- SD) cholesterol levels than the control group (193 +/- 36 vs. 248 +/- 49 mg per deciliter, P0.001), less frequent cardiac rejection accompanied by hemodynamic compromise (3 vs. 14 patients, P = 0.005), better survival (94 percent vs. 78 percent, P = 0.025), and a lower incidence of coronary vasculopathy in the transplant as determined by angiography and at autopsy (3 vs. 10 patients, P = 0.049). There was no difference between the two groups in the incidence of mild or moderate episodes of cardiac rejection. In a subgroup of study patients, intracoronary ultrasound measurements at base line and one year after transplantation showed less progression in the pravastatin group in maximal intimal thickness (0.11 +/- 0.09 mm, vs. 0.23 +/- 0.16 mm in the control group; P = 0.002) and in the intimal index (0.05 +/- 0.03 vs. 0.10 +/- 0.10, P = 0.031). In a subgroup of patients, the cytotoxicity of natural killer cells was lower in the pravastatin group than in the control group (9.8 percent vs. 22.2 percent specific lysis, P = 0.014).After cardiac transplantation, pravastatin had beneficial effects on cholesterol levels, the incidence of rejection causing hemodynamic compromise, one-year survival, and the incidence of coronary vasculopathy.

Multi-component fingerprinting and quantitation of the glucosinolates and nucleosides in samples of Radix Isatidis have been carried out using high-performance liquid chromatography with diode-array detection and electrospray ionization tandem mass spectrometry (HPLC–DAD–ESI/MS). Five nucleosides together with one glucosinolate were identified by comparing retention times, ultraviolet spectra, mass spectra and/or empirical molecular formulae of reference compounds. Quantitation of these six compounds was carried out simultaneously by HPLC on a Phenomenex Luna C18 column using gradient elution with methanol and water and detection at 254 nm. All calibration curves were linear (r>0.9994) within test ranges. Limits of detection and quantitation were 0.33 ng and 2.50 ng on column, respectively. Intra- and inter-day precision (as relative standard deviation) for all analytes was, Graphical abstract Chemical fingerprinting using HPLC-DAD-ESI/MS based on simultaneous identification and quantitation of five nucleosides and one glucosinolate in 25 samples of Radix Isatidis sourced from three pharmaceutical companies has been developed. The contents of the six compounds were subjected to similarity analysis to investigate variations relevant to quality. The method established in this paper is simple and reliable and shows potential for the quality control of Radix Isatidis.

Human leukocyte antigen typing was performed in 32 consecutive Chinese patients with Vogt-Koyanagi-Harada syndrome and 52 unrelated healthy Chinese individuals. Results indicated that HLA-DR4 was identified in 24 of the 32 patients with Vogt-Koyanagi-Harada syndrome (75.0%), but only in 12 (23.1%) of the 52 control subjects (P = .0003; relative risk, 10.0). Human leukocyte antigen-DQw7, also correlated with the disease, was identified in 19 (59.4%) patients, and in 19 control subjects (36.5%; P = .0230). The two-haplotype association detection demonstrated that HLA-DR4 and HLA-DQw7 were related through linkage disequilibrium, suggesting that the disease was primarily associated with only one of the antigens. The comparison between HLA-DR4-positive and HLA-DR4-negative patients with Vogt-Koyanagi-Harada syndrome in regard to clinical manifestations has shown that the HLA-DR4-positive group had a lower visual acuity at the first visit than did the HLA-DR4-negative group. However, both groups responded well to corticosteroid treatment. No other significant correlations between HLA-DR4 positivity and ocular features, including complications or systemic features, were found. Therefore, we concluded that the presence of HLA-DR4 may represent susceptibility to Vogt-Koyanagi-Harada syndrome, but may not represent specific tissue involvement or determine the prognosis. A decreased frequency of HLA-DQw1 in the patient group was also noticed. Further studies showed a higher percentage of HLA-DQw1 in HLA-DR4-positive control subjects than in the HLA-DR4-positive patients (P = .0308), which indicated that HLA-DQw1 was negatively associated with the disease. This protective effect from HLA-DQw1 was also studied.

In this paper, a novel compact optical modulator based on silicon photonic crystals /nano-montmorillonite is proposed. The two-dimensional silicon photonic crystal with triangular lattice and a line defect waveguide formed by a missing row of air holes in the Γ -K direction. The lattice constant is a, and the diameter of the holes is d=0.4a. The holes are filled with the nano-montmorillonite electrorheological fluid, which is made of nanometer sized nano-montmorillonite. The light modulation mechanism of the novel modulator is based on a dynamic shift of the photonic band gap. We have investigated its light modulation performance by using the finite-difference time-domain method. The numerical results show that an excellent optical modulator at a wavelength of 1550nm is achieved. The novel modulator has a high extinction ratio (close to -40dB) and small size (around 10μm). It is very suitable for forthcoming photonic integrated circuits.

Using negative refractive material slow-wave waveguide, a compact and integrated optical modulator is proposed for the first time to our knowledge. The slow group velocities of light, which are readily achievable in negative refractive material waveguide, can dramatically increase the induced phase shifts caused by small changes in the refractive index. This slow propagation is illustrated with a finite-difference time-domain simulation. Modulation operation was demonstrated by using a 40 μm-long negative refractive material slow-wave waveguide of a Mach-Zehnder interferometer (MZI) structure. The modulation depth is 98%.The size of the novel optical modulator is 100 times shorter than that of conventional MZI optical modulator.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We present a microtest for cell-mediated immunity, based on the use of the Tarasaki tray and calcein AM vital dye. The number of target cells needed has been reduced to 500 per test with a corresponding tenfold reduction in the number of effector cells needed. Results were read at the rate of 1 second per test using a fluorimeter attached to a microscope. Each reaction was also confirmed visually with the use of ethidium bromide as a counterstain for dead cells. The calcein AM dye used to stain the living cells was shown to have a low spontaneous leakage rate--less than 15% in 4 hours at 37 degrees C. Dilutions of targets stained by calcein AM had a linear relationship with measured fluorescence values. NK cells, LAKs, and CTLs were readily detectable by this microtest. Quantitation of killing and kinetic analysis was readily performed with this test system. A significant positive correlation to 51Cr-release results was found. We conclude that the microtest should find wide application in studies of cell-mediated immunity.