Simultaneously compensating tunable CD and adaptive PMD using two different nonlinearly chirped fiber Bragg gratings

Experimental research of simultaneous tunable chromatic dispersion (CD) and adaptive polarization mode dispersion (PMD) compensations in optical fiber communication system was reported. Two different nonlinearly chirped fiber Bragg gratings fabricated through the equivalent chirp technology were adopted in the experiment. One of the gratings was used as CD compensator, with a tunable dispersion range from 300 to 600 ps/nm. The other made of photosensitive polarization maintaining fiber was used as a tunable delay line of PMD compensator, which provided a varying amount of differential group delay (DGD) from 40 to 110 ps. Our experiment was operated at 10-Gb/s non-return-to-zero (NRZ) system and the results showed that the eye pattern recovery is excellent after both PMD and CD are compensated. Especially, the power penalty at a bit error rate (BER) of 10-9 is about 1 dB.

Twist characteristics of the ultraviolet-written long-period fiber gratings

Twist characteristics of the ultraviolet-written long-period fiber gratings (UV-LPFGs) are investigated. It was found experimentally that the resonance wavelength of the UV-LPFG shifts to short side proportional to square of the torsion rate, when it is twisted in both directions of clockwise and counter-clockwise, which is different from that of LPFGs written by CO2 lasers, but similar with that of the corrugated LPFGs. The phenomena can be explained by mechanisms of static compression in twisting and index change caused by photoelastic effect.

Ventricular repolarization markers for predicting malignant arrhythmias in clinical practice

Malignant cardiac arrhythmias which result in sudden cardiac death may be present in individuals apparently healthy or be associated with other medical conditions. The way to predict their appearance represents a challenge for the medical community due to the tragic outcomes in most cases. In the last two decades some ventricular repolarization(VR) markers have been found to be useful to predict malignant cardiac arrhythmias in several clinical conditions. The corrected QT, QT dispersion, Tpeak-Tend, Tpeak-Tend dispersion and Tp-e/QT have been studied and implemented in clinical practice for this purpose. These markers are obtained from 12 lead surface electrocardiogram. In this review we discuss how these markers have demonstrated to be effective to predict malignant arrhythmias in medical conditions such as long and short QT syndromes, Brugada syndrome, early repolarization syndrome, acute myocardial ischemia, heart failure, hypertension, diabetes mellitus, obesity and highly trained athletes. Also the main pathophysiological mechanisms that explain the arrhythmogenic predisposition in these diseases and the basis for the VR markers are discussed. However, the same results have not been found in all conditions. Further studies are needed to reach a global consensus in order to incorporate these VR parameters in risk stratification of these patients.

The Characteristic Relationship Between Oil Uptake and Moisture Content during the High Temperature Immersion Frying of Thin Potato Crisps

Thin potato crisps (2mm) were fried at 170℃, 180℃ and 190℃ for various times from 10s to 180s inclusive. It was found that definite oil uptake, moisture loss trends exist during the frying process. No significant difference in the oil uptake or moisture loss rates between flat-cut and ridge-cut crisps exists. Also found in this study was that an increased oil temperature promoted higher moisture loss rates. In turn, the higher moisture loss rates contributed to a higher oil uptake rate. It was found, based on the volumetric plots of oil content vs. water content, that the oil uptake rate was proportional to the moisture loss rate. As a result, it has been shown that there is a possibility of having a characteristic curve of oil uptake against moisture content.

Clinical Study of Drug-resistant Pulmonary Tuberculosis Treated by Combination of Anti-Tuberculosis Chemicals and Compound Astragalus Capsule(复方黄芪胶囊)

Objective: To observe and evaluate the therapeutic effect of anti-tuberculosis (anti-TB) chemicals and Compound Astragalus Capsule (CAC) in combinedly treating drug resistant pulmonary tuberculosis (DR-TB). Methods: Ninety-two patients with DR-TB were equally randomized into the treated group (treated with combination therapy) and the control group (treated with anti-TB chemicals alone). The therapeutic course for both groups was 18 months. Therapeutic effects between the two groups were compared at the end of the therapeutic course. Sputum bacterial negative rate, focal absorption effective rate, cavity closing rate, 10-day symptom improving rate, the incidence of adverse reaction and 2-year bacteriological recurrence rate between the two groups were compared. Results: In the treated group, the sputum bacterial negative conversion rate was 84. 8% , focal absorption effective rate 91. 3% , cavity closing rate 58. 7% and 10-day symptom improving rate 54. 4% , while in the control group, the corresponding rates were 65.2% , 73. 9 % , 37.0% and 26.1 % , respectively. Comparison between the groups showed significant difference in all the parameters (P<0.05, P<0.05, P<0.05 and P<0.01). The incidence of adverse reaction and 2-year bacteriological recurrence rate in the treated group were 23. 9% and 2.6% respectively, while those in the control group 50. 0% and 16. 7% , which were higher than the former group with significant difference ( P<0. 01 and P<0. 05, respectively). Conclusion: The therapeutic effect of combined treatment with anti-TB and CAC is superior to that of treatment with anti-TB chemicals alone, and the Chinese herbal medicine showed an adverse reaction alleviating effect, which provides a new therapy for DR-TB, and therefore, it is worth spreading in clinical practice.

Strong Convergence and Its Rate of Modified Partitioning Estimation for Nonparametric Regression Function under Dependence Samples

In this paper, we study the strong consistency and convergence rate for modified partitioning estimation of regression function under samples that are ψ-mixing with identically distribution.

The Impact of Strengthening Environmental Regulatory Policy on China's Economy——Evaluation Based on CGE Model

This paper has established a computable general equilibrium(CGE) model taking into account the costs of environmental regulation to evaluate the overall impact of enhanced environmental regulation on China's economy.The results demonstrate that if environmental regulation is strengthened to the point at which industrial waste discharge meets the current legal standard,economic growth rate will decrease by approximately1%,employment in the manufacturing sector will decrease by approximately 1.8%,and the total value of exports will decrease by approximately 1.7%.The report also shows that enhanced environmental regulation has impacted each region of China differently.This paper argues that during the implementation of environmental regulation,policymakers will need to have a complete understanding of potential regional and structural impacts.China's environmental regulation policy should be implemented gradually,beginning with key polluting industries and those with low correlation to economic growth.Additionally,this paper proposes that environmental regulation should be carried out during periods of economic growth.

Measurement of mouse liver glutathione S-transferase activity by the integrated method

Objective: The integrated method was investigated to measure Vm/Km of mouse liver glutathione S-transferase (GST) activity on GSH and 7-Cl-4-nitrobenzofurazozan. Methods: Presetting concentration of one substrate twenty-fold above the others and taking maximum product absorbance Am as parameter while Km as constant, Vm/Km was obtained by nonlinear fitting of GST reaction curve to the integrated Michaelis-Menten equation ln [Am/(Am-Ai)]+Ai/(ε×Km)=(Vm/Km)×ti (1). Results: Vm/Km for GST showed slight dependence on initial substrate concentration and data range, but it was resistant to background absorbance, error in reaction origin and small deviation in presetting Km. Vm/Km was proportional to the amount of GST with upper limit higher than that by initial rate. There was close correlation between Vm/Km and initial rate of the same GST. Consistent results were obtained by this integrated method and classical initial rate method for the measurement of mouse liver GST. Conclusion: With the concentration of one substrate twenty-fold above the others, this integrated method was reliable to measure the activity of enzyme on two substrates, and substrate concentration of the lower one close to its apparent Km was able to be used.

RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CONTINUUM THEORIES (Ⅴ)--POLAR THERMOMECHANICAL CONTINUA

The purpose is to reestablish rather complete basic balance equations and boundary conditions for polar thermomechanical continua based on the restudy of the traditional theories of micropolar thermoelasticity and thermopiezoelectricity . The equations of motion and the local balance equation of energy rate for micropolar thermoelasticity are derived from the rather complete principle of virtual power. The equations of motion, the balance equation of entropy and all boundary conditions are derived from the rather complete Hamilton principle . The new balance equations of momentum and energy rate which are essentially different from the existing results are presented. The corresponding results of micromorphic thermoelasticity and couple stress elastodynamics may be naturally obtained by the transition and the reduction from the micropolar case , respectively . Finally , the results of micropolar thermopiezoelectricity are directly given .

Effect of Heating Rates on the Formable Oxide Scale on a C-Steel Surface

Oxide scale formation on a C-steel surface has been investigated using linear heating rates ranging from 0.1℃/min to 10℃/min at high temperatures. The studies on the oxide scale formation at high temperature (650℃) at slower heating rate (0.1℃/min) shows that the kinetic regime is linear. X-ray diffraction measurements revealed that the scale constituents are significantly influenced by the heating rate. The adherence of the scale was improved by using slower heating rate (0.1℃/min-≤650℃), while above such degree the scale was susceptible to cracking and flaking out of the alloy surface. In fact, the development of oxide growth stresses can cause considerable scale cracking. As well, variation of the crystallite sizes under the aforementioned conditions might affect the scale stacking to the alloy surface. The secondary electron detector images of the oxide scale shows that the scale was imperfectly smooth and there were a number of voids and defects in the scale skin, especially at fast heating rate. This observation could be attributed to defects of the as-received alloy. In general, slower heating rate reduced the defects of the scale and improved its adherence.

Separation and Purification of Dodecanedioic Acid from Its Homologous Compounds by Falling Film Crystallization

Separation and purification of dodecanedioic acid (DDDA) from its homologous compounds were studied experimentally by falling film crystallization (FFC). The influences of various operation parameters, including crystallizing time, flow rate of melt and temperature of glycerine bath, on purity of DDDA and crystallizing rate were investigated. Over 99% (by mole) DDDA was obtained for a feed composition of 96% (by mole). The main factors affecting the separation efficiency are flow rate of melt and temperature of glycerine bath. The crystallizing layer of DDDA was further purified by sweating and blasting. A set of optimized operation data are provided for better understanding the mechanism of heat and mass transfer in FFC, and for further industrial application of DDDA purification process.

The Induction Period of Hydrate Formation in a Flow System

The appearance of turbidity due to large numbers of critical size hydrate nuclei may significantly affect the outgoing light intensity and the flow resistance in the pipe loop. The induction period of hydrate formation was determined by analyzing the experimental data——either based on the shading ratio data of laser detector or based on the pressure drop data of the flow system. The induction period of CC12F2 (R12) in pure water and that of CH4 in (tetrahydrofuran ＋ water) systems were then measured with the above two methods. Experimental data show that the induction period depends on the driving force exponentially. Flow rate also has a significant influence on the hydrate nucleation. A new induction period model taking the driving force and liquid flow rate into account was proposed. And it is successfully applied to the calculation of the induction period, which is in good agreement with the experimental data obtained in this study.

The Structure and Size-effect of Calcium Modified Lead Titanate Nanocrystal,Pb_(0.85)Ca_(0.15)TiO_3

ＩｎｔｒｏｄｕｃｔｉｏｎＰＴＣｉｓａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｆｅｒｒｏｅｌｅｃｔｒｉｃｍａｔｅｒｉａｌｏｆｍｏｄｉｆｉｅｄｌｅａｄｔｉｔａｎａｔｅ，ｗｈｉｃｈｃａｎｍａｋｅｔｈｅｔｅｔｒａｇｏｎａｌ／ｃｕｂｉｃａｘｉａｌｒａｔｉｏｏｆｌｅａｄｔ...

SURGICAL TREATMENT OF HILAR BILE DUCT CARCINOMA

From June, 1986 to June 1989, 24 cases of hilar bile duct carcinoma were explored in the Surgical Department of General Hospital of PLA, 16/24 cases were resected, a resectability rate of 66%. The increase of resectability rate was due to earlier recognition of this condition and the extension of surgery, including major resection of liver as well as radical dissection of the hepato-duodenal ligament and repairative operations on the blood vessels. Among these 16 cases, major hepatic resection was performed in 10 cases, in which, 3 cases of resections of the middle lobe of the liver were done instead of right or extended right lobectomy. No operative mortality in the 30 days' postoperative period, but the postoperative morbidity rate was still high and most of the complications were related to biliary leakage and infection. Three patients died in the follow up period at 6, 14 and 15 months respectively. All of them died from biliary infection. The remaining 13 patients were still alive, the longest being 40 months and the average living time was 16.1 months. Probably, lowering of the operative mortality rate and morbidity rate are still the most important considerations in the surgical treatment of hilar carcinoma at the present time. Extensive liver resection especially on the right side, carried a high mortality rate in the deeply jaundiced patients. We considered that preoperative PTCD was of much less value than that used in lower bile duct obstruction such as tumors of the periampullary region. Preservation of the superior and posterior portion of the right lobe of the liver may be of advantages as to lowering postoperative hepatic failure and infection of the right subphrenic space as observed in this series of cases.

Fast estimation of Michaelis-Menten constant of arylesterase with a pair of medium concentrations of substrate

Objective: To investigate the reliability for fast estimation of Michaelis-Menten constant (Km) with calibrated specific activity at only two medium concentrations of substrate by both simulation and experimentation with arylesterase (ArE)as model. Methods: Initial rates were simulated by randomly inserting uniform absolute error, and the experimental initial rates of ArE were determined by measuring the increaser of product absorbance. Calibrated specific activities at two substrate concentrations were obtained by regression analysis, and Km was calculated according to Michaelis-Menten equation. Results: By simulation with calibrated specific activities at two medium substrate concentrations, Km could be calculated according to Michaelis-Menten equation with reasonable precision and accuracy. By experimentation with substrates of 2-naphthyl acetate, phenyl acetate, and p-nitrophenyl acetate, there were no differences between the mean and SD of Km of ArE for either substrate by this linear kinetic method and the Lineweaver-Burk plot. Conclusion: This linear kinetic method was reliable for fast estimation of the Km of some specified enzyme on its substrate of lower solubility or lower sensitivity for quantification by common methods.

Evaluation of Relationship Between Clothing Pressure of Men's Suit and Comfort

An investigation on relationship between clothing pressure of men's suit and wearing comfort is conducted. With the pressure measurements at different parts of men's suit under normal standing posture and in motion, the objective assessment of the total comfort are related to the subjective ratings of clothing pressure. There is a common strong sensation of pressure on shoulder with normal standing posture, and a strong relationship between total conffort and clothing pressure in back armhole and the front of upper arm with posture in motion.

Stability and Drag Reduction in Transient Channel Flow of Fibre Suspension

Drag reduction features in the transition regime of channel flow with fibre suspension were analyzed in terms of the linear stability theory. The modified stability equation was obtained based on the slender-body theory and natural closure approximation. Results of the stability analysis show attenuating effects of fibre additives to the flow instability. For the cases leading to transition, drag reduction rate increases with the characteristic parameter H of fibres. The mechanism of drag reduction by fibres is revealed through the variation of velocity profile and the decrease of wall shear stress. The theoretical results are qualitatively consistent with some typical experiments.

The Characteristics of Ground Flashes in Beijing and Lanzhou Regions

Over twenty thousand lightning location data obtained by using Lightning Location System(LLS) from Lanzhou and Beijing regions have been analysed to ascertain the characteristics of ground flashes in both regions. The strength of positive flashes is 5 times higher in Lanzhou than in Beijing. The strength of positive flashes is 3 times and 2.2 times as large as negative flashes in Beijing and in Lanzhou respectively. It has been found that the strength of positive and negative flashes is submitted to the normal distribution, and is independent of the characteristics of thunderstorm. So the lightning strength obtained by DF may be used to forecast the coming of thunderstorm. Although the stroke number in both regions decreases as exponent regulation, the maximum number of return stroke for one lightning in Beijing is more than that in Lanzhou. The peak flash rate occurs in late afternoon for both regions, but the maximum and minimum flash rate appeared an hour earlier in Beijing than in Lanzhou.The relationship between DF display and lightning radiation electric field, discharge current is obtained.

Role of p38MAPK in mediating TNF-α-induced apoptosis of rat glioma cell line C6

Objective: To study the role of p38MAPK in mediating TNF-α-induced apoptosis of rat glioma cell line C6. Methods: Effect of TNF-α on the proliferation of C6 cells was determined by MTT assay. The TNF-α induced apoptosis was detected by transmission electron microscopy and flow cytometry. The expression of p38MAPK was detected by SABC method and Western-blot. The effect of SB202190, a specific inhibitor of p38MAPK, on TNF-α-induced apoptosis was observed by flow cytometry and SABC method. Results: Inhibitory rate of TNF-α(2×105 U/L) on C6 cells was 43.75%. In the TNF-α treated group, apoptotic cells were observed by transmission electron microscopy and the apoptotic rate was 37.5% by flow cytometry. p38MAPK positive signals were detected by SABC method and Western-blot. In the SB202190 treated group, the apoptotic rate was 7.0% and no p38MAPK signals were found. Conclusion: Apoptosis of C6 cells and expression of p38MAPK can be induced by TNF-α. The activation of p38MAPK promotes the apoptosis of C6 cells.

Study on an Atmospheric Pressure Plasma Jet and its Application in Etching Photo-Resistant Materials

An atmospheric pressure radio-frequency plasma jet that can eject cold plasma has been developed. In this paper, the configuration of this type of plasma jet is illustrated and its discharge characteristics curves are studied with a current and a voltage probe. A thermal couple is used to measure the temperature distribution along the axis of the jet stream. The temperature distribution curve is generated for the He/O-2 jet stream at the discharge power of 150 W. This jet can etch the photo-resistant material at an average rate of 100 nm/min on the surface of silicon wafers at a right angle.