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PURPOSEWe aimed to explored the influence of preoperative gamma knife treatment on the clinical effect of microsurgical resection of vestibular schwannoma.METHODSThe patients who underwent vestibular schwannoma resection in our hospital between November 2010 and December 2019 were retrospectively collected. According to retrospectively collected data, the patients who met the inclusion and exclusion criteria were defined as group A. The 1:3 ratio design was adopted in this study to select the group B that was not subjected to gamma knife treatment in the same period. The pre/postoperative clinical manifestations, neurological function grade, postoperative complications, tumor recurrence and increase were collected and compared between the two groups.RESULTSThere were 40 patients in group A and 120 patients in group B. At the last follow-up, the number of patients with poor facial nerve function was 15 (39.5%) in group A and 25 (21.2%) in group B (P = 0.025). In group A and group B, disequilibrium occurred in 14 patients and 17 patients respectively after operation (P=0.003). 7 patients caught the pulmonary infection in group A and 3 patients had a pulmonary infection in group B (P=0.03) after operation. CONCLUSIONSwhen a patient with vestibular schwannoma undergoes microsurgical surgery, the preoperative history of gamma knife treatment will make a recovery from postoperative facial paralysis difficult for the patients, making them more prone to suffer from postoperative disequilibrium and postoperative pulmonary infection.

The model of “SPOC+ flipped classroom”, aided by top teaching resources and information technologies, have proved highly effective in making up deficiencies of traditional teaching. The task-based teaching model could better stimulate creativity of students and improve their skills by raising questions and solving problems. This paper took the course Safety Design and Analysis as an example to explore reforms of the task-based teaching model of “SPOC+ flipped classroom” and proposed a system integrating modules of “theory+ experiment+ tasks”. It proposed a five-step task-based model incorporating “questions, design, knowledge, method and application”, and designed an online and offline mixed teaching model including “online independent learning, clarification, classroom demonstration, group discussion, and after-class extension activities. The perfect integration of teaching and learning further enhanced students” awareness of independent learning, thus improving the teaching efficiency.

According to President Xi Jinping's important statements, all kinds of courses should go hand in hand with the ideological and political theory course, and curriculum politics is a new trend in the ideological and political education reform of military academies. At present, with the continuous development of information technology, information-based teaching has become an important teaching means of military academies. In order to improve the teaching effect, military academies apply information-based teaching means into the construction of curriculum politics. Great preliminary results have been achieved, but there are still many shortcomings. To address the problems in the construction of curriculum politics in military academies, this paper explores the in-depth integration of classroom teaching and information technology. Based on several online teaching platforms, the information-based teaching paradigm is established. Through the “online + offline” blended teaching mode, the teaching mode of curriculum politics is optimized and the teaching level and quality are significantly improved, which can strengthen moral education and talent cultivation.

Case-based teaching, as a heuristic teaching method combing theory and practice and an important approach to practical course teaching, allows students to experience and discover knowledge in person directly and indirectly. A new implementation pattern has been provided for it with the constant promotion of information technologies and teaching platforms. This paper introduces the origin and development of case-based teaching, analyzes the connotation of teaching cases and case-based teaching deeply, discusses the methods of compiling teaching cases, and meanwhile puts forward effective measures for the implementation of case-based teaching based on information technologies in a targeted way under the background of military academies in combination with existing problems in the process of case-based teaching.

Coherent diffraction imaging (CDI), a type of lensless imaging method, relies on the use of light source with high-degree coherence to compute highly resolved complex-valued objects. The coherence of light source consists of temporal coherence and spatial coherence. In practice, it is difficult to obtain a fully coherent source. Spatial decoherence can be generated in the following three scenarios: no synchronization mechanism for the whole radiation source, a finite (non-zero) point spread function of the detector, and the sample variation within exposure time. Partial temporal coherence means that the beam is not quasi-monochromatic, behaving as the energy spread of the illumination. The consequence of reduced degree of temporal and/or spatial coherence in CDI is the decrease of visibility in the measured diffraction intensity. A fundamental assumption of CDI is the full temporal and spatial coherence, and even a relatively small deviation from full coherence can prevent the phase retrieval algorithm from converging accurately. It is necessary to break the barrier of limited coherence by improving the experimental setups directly or optimizing the phase retrieval algorithms to mitigate decoherence. Based on the Wolf’s model of coherence-mode of light and the framework of CDI using partially coherent light proposed by Nugent et al., various methods have been proposed to solve the problems induced by low coherence. Those methods generally experience a similar development process, that is, from the requirement for measuring the spatial (coherent length or complex coherent factor) or temporal (spectrum distribution) coherence properties to without the need for such priori knowledge. Here in this work, the principles of partial coherent CDI, and the major progress of CDI with partial spatial- and temporal-coherent light are reviewed.

Objective: To evaluate the efficacy of intraoperative three-dimensional (3D) Iso-C C-arm- navigated percutaneous radiofrequency ablation (RFA) of osteoid osteomas.Methods: 35 patients (20 males and 15 females) with osteoid osteomas underwent treatment with intraoperative 3D Iso-C C-arm navigation-guided RFA. The tumour was first biopsied for pathological examination, the core needle was removed and the RFA needle was inserted into the nidus. Post-operative X-rays and CT scans were performed to evaluate the degree of ablation and to assess for recurrence at 3-month follow-up. Patients also completed a visual analogue scale (VAS) both pre-operatively and 3 days post-operatively to subjectively assess pain.Results: Pathological diagnosis confirmed osteoid osteoma in 19 cases. The other 16 cases were not pathologicallydiagnosed owing to inadequate biopsy specimens. In all cases, localized pain was immediately relieved following RFA. Patients reported significantly decreased pain, with mean pre- operative VAS scores of 3.4 reducing to 0.80 at 3 days post-operatively and further to 0.06 at 3-month follow-up (p ,0.05). The mean follow-up time was 15.5 months (range: 3–38 months).Conclusion: 3D Iso-C C-arm navigation-guided RFA is a safe and effective option for the treatment of osteoid osteomas and may be considered in place of intra-operative CT-guided and open resection.Advances in knowledge: C-arm image-guided percutaneous RFA mitigates the need for pre- operative CT as well as intraoperative scintigraphy, provides real-time imaging of the anatomy, facilitates accurate resection of the tumour and enables immediate confirmation of excision.

Based on the frequency response model,high frequency characteristic analysis for the TO packaged avalanche photodetectors is presented.The influence on frequency performance of TO packaging,including chip,bondwire,transimpedance amplifer,and TO header elements are investigated.By changing inductance parameters induced by different bandwires,the different frequency responses are observed.Finally,by considering the engineering conditions,a-3 dB bandwidth of 10GHz is optimally obtained for TO packaging.

The effects of Gamma value,color temperature and brightness parameters on the display colors were researched in this paper.The experimental results show that the appropriate gamma value can improve the image display quality;the effect of color temperature on display color is more than gamma,it can be chosen according to the specific work environment of the monitor;brightness has almost no effect on display color,it can be chosen according to the observing conditions.

We report the case of a 46-year-old man with von Hippel-Lindau (VHL) disease, manifesting disseminated leptomeningeal hemangioblastomatosis. The patient initially presented with a solitary hemangioblastoma in the right cerebellum. Later, he was diagnosed with VHL disease and underwent several surgical procedures in the following 14 years. But the prognosis was poor. Recently, the hemangioblastomatosis disseminated along leptomeninges involving both brain and spine. We aim to analyze the possible reason for the leptomeninges dissemination, discuss the imaging characteristics of this rare disease with ominous manifestation and propose the optimal strategy for treatment. We think the optimal treatment strategy should be surgical biopsy and surgical decompression. A long-term follow-up is inevitable. Antiangiogenic medication might be the hope for remission of this disease.

By pulsed anodic etching at low temperature, we prepared a porous silicon reflector with a photonic band gap centred in the long-wavelength infrared spectral region (centred at about 12 μm). After proper oxidation process, the stable reflector structure, which can reflect electromagnetic wave from 8μm to 12μm (centred at 10μm) within wide incidence angles (about 50°), is obtained. The wavelength shift of absorption peak of Si-H and Si-O shows the influence of oxidation process and indicates the stability of oxidized porous silicon dielectric reflector, which offers possible applications for the room temperature infrared sensor.

This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the range 1450–1650 nm from erbium-doped single-mode tellurite glass-fibre is obtained upon excitation of a 980-nm laser diode. The effects of the length of glass-fibre and the pumping power of laser diode on the amplified spontaneous emission are discussed. The result indicates that the tellurite glass-fibre is a promising candidate for designing fibre-optic amplifiers and lasers.

Considering the fact that the temperature distribution in furnace of a tangential fired pulverized coal boiler is difficult to be measured and monitored, two-stage numerical simulation method was put forward. First, multifield coupling simulation in typical work conditions was carried out off-line with the software CFX-4.3, and then the expression of temperature profile varying with operating parameter was obtained. According to real-time operating parameters, the temperature at arbitrary point of the furnace can be calculated by using this expression. Thus the temperature profile can be shown on-line and monitoring for combustion state in the furnace is realized. The simulation model was checked by the parameters measured in an operating boiler, DG130-9.8/540. The maximum of relative error is less than 12% and the absolute error is less than 120 °C, which shows that the proposed two-stage simulation method is reliable and able to satisfy the requirement of industrial application.

Objective: To evaluate the clinical efficacy of Shengmai Powder (SMP) in treating acute viral myocarditis objectively.Methods: One hundred and twenty-four patients with acute viral myocarditis were randomized into the treated group (SMG,n = 64) and the control group (CG,n = 60). Such myocardial nutrient medicine as ATP, CoA, Vit-C, were given to both groups. And to the treated group, 40 ml of Shengmai Injection per day was given intravenously for 2 weeks, which was followed by oral intake of Shengmai granule, one package three times daily for another 2 weeks in total. The same anti-arrhythmia agents were applied to both groups, and no fructose-1, 6-diphosphate (FDP) for either. Semi-quantitative scoring method was adopted to observe such symptoms as chest stuffiness, palpitation and chest pain before treatment and four weeks after treatment. Meanwhile, ECG, dynamic ECG by Holter monitor, left ventricular enddiastolic dimension (LVEDD), left ventricular ejection fraction (LVEF), serum neutralizing antibody of virus Coxsackie B, cardiac troponin I (cTnl) and cardiac troponin T (cTnT) were examined.Results: (1) Compared with the control group, more significant improvement was got in SMG in respects of chest stuffiness, palpitation, chest pain and arrhythmia (P

A birefringent Fourier transform imaging spectrometer with a new lateral shearing interferometer is presented. The interferometer includes a Wollaston prism and a retroreflector. It splits an incident light beam into two shearing parallel parts to obtain interference fringe patterns of an imaging target, which is well established as an aid in reducing problems associated with optical alignment and manufacturing precision. The proposed method provides a direct technology for robust and inexpensive spectrometers to measure spectral signatures. Formulas for the optical path difference (OPD) produced by the proposed birefringent interferometer are derived by the ray-tracing method. Two experiments are carried out to demonstrate the accuracy of the formulas for OPD in the inner scanning mode and window scanning mode, respectively. A laser of wavelength 650 nm is used as a source of the experimental setup. The experimental estimations of the OPD and a reference OPD curve obtained with theoretical analysis are used for comparison. The match between the two curves is highly consistent, for the maximum deviation of the experimental OPD is less than /4. For the further verification of the imaging performance of the proposed method, another experiment is performed. A scene illuminated by an incandescent lamp is used as an imaging target. The temporal rotating of the retroreflector produces a series of time sequential interferograms, where the target is fixed and fringe patterns move. Performing nonuniform fast Fourier transform of the interferogram data produces a spectral data cube (i.e., the spectral images of the target).A series of recovered spectral images whose center wavelengths range from 450 to 650 nm is presented.In this paper, the principle of the instrument is described, and the OPD distribution formula is obtained and analyzed. The performance of the system is demonstrated through a numerical simulation and three experiments. This work will provide an important theoretical basis and the practical instruction for designing a new type of birefringent Fourier transform spectrometer based on Wollaston prism and its engineering applications.

In this paper the steady simulation and optimization were carried on for the synthesis of oxalate by carbon monoxide coupling-regeneration reaction in the gaseous phase with sequential modular approach modification software ASPEN, PRO/? and programs about two-dimension quasi-homogeneous reactor and gas—liquid bubble column reactor. At the same time, the influence of various operating parameters were investigated and the optimal operation range was determined. As well as the significant test about the simulation results and experimental results were carried out and the belief level is 95%.

A self-starting, passively mode-locked all-fibre ring laser based on the homemade Er3+/Yb3+codoped phosphate glass fibre is reported. Dual-pump sources were used to achieve the mode-locked operation in the experiment. The fundamental mode-locked pulse repetition rate is 10.67 MHz. The pulse duration, assumed as the fit of hyperbolic secant pulse shape, is 5.82ps. We also observe the multi-pulse output of the fibre laser.

We experimentally study a novel fibre with high gain per unit length based on the homemade erbium–ytterbium codoped phosphate glass. The gain and noise characterizations with different pump powers at different wavelengths are investigated. The 1.8-cm-long fibre, dual-pumped by two single mode 980-nm fibre-pigtailed laser diodes, provides a gain per unit length greater than 3.0 dB/cm and a noise figure less than 6.5 dB. The gain saturation behaviour at 1535 nm is obtained and the saturation output power (3 dB compression) is greater than 5 dBm.

Objective To observe the efficacy of electroacupuncture plus TDP for treating functional dyspepsia

The research of palm print features has attracted a lot of attention, and the principal lines which is one of the stable and important features in palm print images can provide effective information for application of palm print technology. Aimed to accurate and natural extraction, in this paper, an associated extraction method of palm print principal lines is presented based on the own properties of palm print images. The method consists of three steps: coarse segmentation, principal lines position and accurate extraction. Firstly, the coarse segmentation was obtained by Nib lack's method. Secondly, SUSAN operator was applied to limit the range of principal lines as position result. Finally, the accurate extraction was achieved by the intersection of those two outputs mentioned above. Besides, we also adopted alternating sequential filter to solve thining problem. The experimental results with different shapes of palm print showed that this method is effective for capturing detailed and accurate structural information.

XH27 is a heavy oil reservoir with a high oil/water viscosity ratio that incurs bottom water coning effects. To enhance the primary heavy oil production, 59 vertical wells with a 141-m square well pattern have been drilled since 1992. The highest primary oil production of 360 tons/day was reached in 1994. Starting in 1996, the reservoir fell into a significant production decline phase. The reservoir was on the brink of obsolescence in 2006 when a 93.6% water-cut discharge and a 0.26% annual oil recovery factor were recorded. Based on detailed static reservoir characterization and updating of the dynamic reservoir model, the square vertical well pattern development strategy was shifted to a horizontal well drilling venture with a net-remaining-oil-distribution pattern. The major shortcoming to overcome was accurate placement of the horizontal section trajectory close to the reservoir top for the injector-producer wells. The thin oil-column target of less than 5 m added to the challenge. To overcome these challenges, real-time well placement monitoring using high-resolution resistivity images, along with near-bit measurements, has been applied in all horizontal wells drilled. Clear identification of structural dips enabled the accurate reservoir model adjustment and allowed decisions on accurate trajectory corrections to be made while drilling. A total of 33 horizontal injector-to-producer wells have been executed successfully. Three years from the inception of the new strategy, the average secondary production improved to 380 tons/day, which is higher than the best daily production during the course of primary production. The oil recovery is expected to double. The application of the new horizontal well drilling pattern strategy, along with fit-for-purpose well placement technology, in the XH27 heavy oil reservoir has significantly increased the oil production and enhanced the recovery factor. The nearly obsolete heavy oil reservoir can be turned into an economically developed field.

A new approach to the experimental investigation of the steady-state stability of controlled rectifiers based on the measurement of the angle between sequential ignitions of the valves is discussed. The statistical treatment of the experimental data shows a special dependence on the deviation of the firing impulses and the amplifier gain factor. Such dependence provides a physical definition for the rectifier stability and its boundaries. The experimental investigation of the increasing of the impulse deviation with an increase of the gain factor has shown that the physical reason for such deviation change and rectifier instability is an increase of a varying component in the control voltage of the firing system input. Analyzing the data about the well-known forms of the rectifier's instability-harmonic, ripple, and low-frequency-it can be concluded that the physical reason for the stability loss is the same: increase of alternating component in the firing control voltage. In conclusion, a new classification of rectifier instability forms is discussed.

In this paper, Complex Network theory is applied to macroscopic research of C2 system, and based on fitness degree model of scale-free network, the topological properties and robustness of C2 Complex Network are discussed. In view of the cascading failures of Complex Network, the node dependency degree parameter and the adjustable increasing parameter are added to the load-capacity model, and the fundamental research approach to the cascading failures of C2 system, which opens a new way for the research of macroscopic law of C2 system.

Map Reduce programming model is designed to process large data sets in-parallel on large clusers. But most organizations can't afford to built a large cluster, so building a small cluster to improve the efficience of time-consuming applications is a perfect solution. Besides, non-data-intensive programs are common. Is Map Reduce suitable for this kind of programs? In this paper, a small cluster consisting of 5 PCs is built, with its configuration adjusted. Then a distributed FTP scan program is written to test whether Map Reduce is suitable for small data sets, network-intensive program. Finally a distributed string search program is written to test the performance of Map Reduce on large data sets. The results show that Map Reduce can run efficiently on small cluster, and it's also suitable for small data sets, network-I/O-intensive programs.

Choppers are widely used for traction motor control in electric automobiles and other electric transportation system. In those applications, control of dc motor's speed is required where the supply is dc or an ac voltage that has been rectified. This paper presents work on development of four quadrant DC chopper based on the SPMC topology, an advanced topology that hypothetically could perform many different converter functions. Prior to hardware implementation a computer simulation model was developed using the Power System Block Set (PSB) within the MATLAB/Simulink (MLS) environment, to study the behaviors of the proposed converter. Successful results presented are mainly due to the use of resistive load to reduce complexities. Results from PSB simulation are compared with those obtained from PSpice to ascertain its validity. The output is being synthesized using Pulse Width Modulation (PWM) technique. It is shown that the same SPMC topology could be used as a DC chopper extending the versatility of the topology a desirable feature in the future as increases in costs for skilled manpower could be traded-off with versatile technology.

In this paper, non-contact anthropometry is done on the female bodies, and the 3D point-cloud data is got by 3D scanner, and then the collar curve of female tight prototype is generation by data processing on point-cloud figures using reverse engineering software. The collar curve can be divided into the front and back collar curve. The characteristic points of the front collar curve are points of side neck and front neck, and the characteristic points of the back collar curve are points of side neck and back neck. By making the cross sections of the above points, the depth and width of the front and back collar curves are got, and according to the principle of equant depth four related points are inserted in the front collar curve, and three related points are inserted in the back collar curve.

Background and objective During the resection of jugular foramen tumors via the basic far lateral approach, the jugular foramen tumor area as well as its adjacent structures, especially the intracranial part, can be better exposed, which avoids stripping of the petrous part of temporal bone and displacement of facial nerve, and protects the patient's hearing from damage. However, when applied in tumors developed from ventral to the brain stem and middle fossa, with extracranial tumors, this surgical approach seems to be inadequate and limited. This study was to explore the microsurgical technique and clinical value for treating giant dumbbell-shaped tumors at jugular foramen (JF) via a modified far lateral approach. Methods A retrospective analysis was performed in 16 patients with huge dumbbell-shaped tumors at JF which were removed through the modified far lateral approach (suboccipital transjugular-jugular tubercle-jugular process) between January 2001 and December 2008. The process of operation, and pre-and postoperative clinical data were included in the analysis. Results Gross total tumor removal was achieved in 14 cases, subtotal removal in 1 case, and partial removal in 1 case. Follow-up examinations in most patients demonstrated that the patient with an obvious preoperative deficit had a good recovery. During the follow-up from three months to seven years, 10 (76.9%) cases with lower cranial nerve involvement showed obvious improvement of symptom after operation, 8 (80.0%) cases with facial palsy obtained various degrees of alleviation, and 7 (77.8%) cases with hearing impairment at different levels restored hearing. Two patients developed new lower cranial nerve palsies after operation, and underwent functional rehabilitation in the three-month follow-up. Conclusions Modified far lateral approach is helpful for removing the huge tumors at JF, especially for tumors extending to the petroclival region ventral part of pontomedullary junction. It has a higher rate of total resection, preoperative cranial nerve function impairment is expected to restore, and also has the advantage of protecting the facial nerve, labyrinth and vertebral artery structure from unnecessary damage.

The fundamentals, up-to-date research, and developing techniques of coastal environmental monitoring are introduced. Data analysis, infrastructure, modulization, and functional design of Zhejiang Coastal Pollution Monitoring Geographical Information System are discussed. Its database design and realization is put forward. The pollution analysis in the system is evaluated and the research is summarized.

Standard IEC61968 and IEC61970 enacted by International Electrotechnical Commission (IEC) built a basic model for the equipment objects in electric power system. According to the actual needs in state evaluation of substation equipment, unified model of substation equipment state information was established. The model follows standard Common Information Model (CIM). By researching the related information and components of substation equipment, the model was classified as Core3 Package, Domain3 Package, History Package, Substation Equipment Package, and Test Package. The five packages generalize the description of the substation equipment, equipment testing, historical data and other aspects. This model built an integrated information platform for the state evaluate of substation equipment and offered exhaustive substation equipment state information for apparatus attendant and relevant units. With the model substation equipment state information became more unified.

In this paper, a research about air-drive AMT (automatic mechanical transmission) fault diagnostic system is made. The redundancy analysis method and action analysis method are used to detect the failures in the AMT system and a fault diagnostic system of air-drive AMT in heavy commercial vehicle is developed by model based design which is very adapt to the development of automotive control system. The fault diagnostic models of sensors and execute components in AMT system are successfully built in Matlab/Simulink. The fault diagnostic models are implemented through a RCP (rapid control prototyping) experiment based on dSPACE.

To protect the environment and enhance the human health, the lead-free process is speeded up rapidly in recent years. However, on the way to lead-free process, lead and lead-free materials will be used within the same mounting process for the manufacturers of electronic products. Therefore it is necessary to study the reliability of the mixed solder joints. Based on BGA device, this paper analyzes the reliability of the mixed solder joints with thermal cycling loading by ANSYS software, and predicts the thermal fatigue life of the joints by modified Coffin-Manson equation. The order of the thermal fatigue life of the joints is: lead-free solder joints >FWC solder joints >BWC solder joints (uniform structure) >lead solder joints >BWC solder joints (non-uniform structure). A case study is given. The result shows that the reliability of lead-free solder joints and mixed solder joints (uniform structure) are better than that of lead solder joints.

An erbium-doped phosphate glass fibre has been drawn by the rod-in-tube technique in our laboratory. The gain for the Er3+-doped phosphate glass fibre with different pump powers and with different input signal wavelengths is investigated. The 2.2-cm-long fibre, pumped by a single-mode 980-nm fibre-pigtailed laser diode, can provide a net gain per unit length greater than 1.8 dB/cm. The pump threshold is about 50 mW at the wavelength of 1534 nm, and below 70 mW at 1550 nm. The gain linewidth of the Er3+-doped phosphate glass fibre is greater than 34 nm and can cover the C band in optical communication networks.

A compact low noise single frequency linearly polarized distributed Bragg reflector (DBR) fiber laser based on a 1.4-cm-long homemade Er3+/Yb3+ -codoped phosphate single mode glass fiber has been demonstrated. An over 50 mW stable single frequency linearly polarized fiber laser was achieved. The measured slope efficiency is more than 21.6%, and the signal-to-noise ratio (SNR) is higher than 65 dB and the laser linewidth is less than 2.0kHz. The laser RIN is measured to be less than −150 dB/Hz at the frequencies over 2.0MHz, and the obtained linear polarization extinction ratio (LPER) is more than 30 dB.

Highly Er3+/Yb3+-codoped single-mode phosphate glass fibre is fabricated by the rod-in-tube technique. The performances of high-concentration Er3+/Yb3+-codoped phosphate glass fibre amplifiers are investigated and discussed. An efficient optical fibre amplifier with a gain of 12.6 dB based on a 3.0 cm long Er3+/Yb3+-codoped phosphate glass fibre is demonstrated under a dual-pump configuration with two 976 nm fibre-pigtail laser diodes, which make it attractive for compact Er3+ -doped fibre amplifiers. The obtained noise figures of signal wavelength from 1525 to 1565 nm are less than 6.0 dB. Gain saturation behaviour at 1535 nm is also investigated, and the obtained saturation output power is larger than 10 dBm.

With the aid of photolithography, an array of one-dimensional porous silicon photonic crystal reflector islands for a far infrared image detector ranging from 10 μm to 14 μm is successfully fabricated. Silicon nitride formed by low pressure chemical vapor deposition (LPCVD) was used as the masking layer for the island array formation. After etching, the microstructures were examined by a scanning electron microscope and the optical properties were studied by Fourier transform infrared spectroscopy, the result indicates that the multilayer structure could be obtained in the perpendicular direction via periodically alternative etching current in each pre-pattern. At the same time, the island array has a well-proportioned lateral etching effect, which is very useful for the thermal isolation in lateral orientation of the application in devices. It is concluded that regardless of the absorption of the deposition layer on the substrate, the localized photonic crystalline islands have higher reflectivity. The designed islands structure not only prevents the cracking of the porous silicon layers but is also useful for the application in the cold part for the sensor devices and the interconnection of each pixel.

We experimentally investigate the laser characteristics of a series of short pieces of newly-developed Er3+/Yb3+ codoped single mode phosphate glass fibres via the cladding pump of a 976nm multimode laser diode. A stable continuous-wave single transverse mode laser with over 85mW at 1553 nm is generated from a 5.5-cm-long active fibre. Single mode laser output power per unit length is up to 15mW/cm. Moreover, the slope efciency is 11.8% when the pump power is below 940mW and the 3dB linewidth is 0.06nm at the maximum pump power. The numerical simulation results show that the laser emission slope efficiency can exceed 20% by means of increasing the coupling efficiency of the pump to the fibre core further.

A focused transducer，featuring extended focal zone，is employed for scanning photoacoustic mammography.Using the transducer with extended focal zone，a large tissue sample can be imaged conveniently.Phantom experiments demonstrate that the location，size and optical energy deposition of absorbers can be imaged correctly.The depth and lateral resolution of image is 0.3mm and 2mm，respectively.And the transducer can be applied in conventional ultrasonic technology to achieve multimode diagnosis as well.Preliminary study shows that this method could be potential in early diagnosis of breast cancer.

Electroluminescence (EL) from Sibased organic microcavity has firstly been reported in the literature. The microcavity is made up of the central active multilayers sandwiched between a silver film and a porous silicon Bragg reflector (PSDBR), formed by electrochemical etching of p+Si substrate in the electrolyte of HF: C2H5OH:H2O. The central active multilayers consist of Al (1 nm) / LiF (05 nm) / Alq3 / Alq3: DCJTB / NPB / CuPc / ITO / SiO2． The reflectivity (relative to an Al mirror) of the PSDBR is up to 99%, and the stopband is about 160 nm wide. Resonant cavity mode appears as a tip in the reflectivity spectrum of the Sibased organic multilayer films, indicating that the Sibased organic multilayer structure is indeed a microcavity. The peak widths of the EL spetra are greatly reduced from 70 nm to 12 nm as compared with those measured from noncavity structures. Note that the EL emission from the cavity devices is singlemode, and the offresonant optical modes are highly suppressed. Moreover, an increase of a factor of about 4 of the resonant peak intensity is observed. In addition, the currentbrightnessvoltage characteristics and the effect of parameters on the lifetime of the cavity devices are also discussed. The present technique for obtaining enhanced EL emission from Sibased organic microcavity may also be another novel effective method for realizing allSibased photonic devices and optoelectronics device integration.

The experiments are carried out in the system of continuous flow reactors with dielectric-barrier discharge (DBD) for studies on the conversion of natural gas to C 2 hydrocarbons through plasma catalysis under the atmosphere pressure and room temperature. The influence of discharge frequency, structure of electrode, discharge voltage, number of electrode, ratio of H 2 /CH 4 , flow rate and catalyst on conversion of methane and selectivity of C 2 hydrocarbons are investigated. At the same time, the reaction process is investigated. Higher conversion of methane and selectivity of C 2 hydrocarbons are achieved and deposited carbons are eliminated by proper choice of parameters. The appropriate operation parameters in dielectric-barrier discharge plasma field are that the supply voltage is 20—40 kV (8.4—40 W), the frequency of power supply is 20 kHz, the structure of (b) electrode is suitable, and the flow of methane is 20—60 mL·min -1 . The conversion of methane can reach 45%, the selectivity of C 2 hydrocarbons is 76%, and the total selectivity of C 2 hydrocarbons and C 3 hydrocarbons is nearly 100%. The conversion of methane increases with the increase of voltage and decreases with the flow of methane increase; the selectivity of C 2 hydrocarbons decreases with the increase of voltage and increases with the flow of methane increase. The selectivity of C 2 hydrocarbons is improved with catalyst for conversion of natural gas to C 2 hydrocarbons in plasma field. Methane molecule collision with radicals is mainly responsible for product formation.

The construction of an organic microcavity with an organic light-emitting thin f ilm sandwiched between a porous silicon Bragg reflector and a silver film is dem onstrated.The peak widths of the PL spectra are greatly reduced from 83nm to 4nm as compared with those measured from non-cavity structures.The off-resonant opt ical modes are highly depressed.As is always observed from an optical microcavit y,the peak intensity is enhanced,and the peak position shows a blue shift with i ncreasing exit angles.

From 91,725 autopsies, 28 cases of peripheral intrahepatic cholangiocarcinoma were selected to study the wide spectrum of histopathology of the tumor. The results showed that two cases (7.14 %) had predominantly solid type. One case had pure, and six had predominant cordai type (25%). Four showed pure, another four showed predominant ductal type (28.57%). Six (21.43%) revealed glandular pattern, one of which consisted of this pure component. Fapillary type was present in three cases (10.71 %) with two entirely made of this conformation. One case (3.57%) was classified as adenosquamous type and another one (3.57%) fell into the undifferentiated category. No obvious correlations between histological subtypes and underlying liver disease, stroma reaction or biological behaviour have been found. The significance of the classification in the tumor diagnosis and differential diagnosis, as well as possible mechanisms of carcinogenesis in these patients are discussed.

Success or failure of open heart surgery is closely related to the effect of myocardial protection, and at present there is no unanimity of opinion as to the ideal protecting method. In this paper we compared the effects of myocardial protection on isolated rabbit heart afforded by the cold (4°C) oxygen-carrying perfluorotripropylamine (FTPA) cardioplegic solution (group A) and those afforded by the cold (4°C) St. Thomas cardioplegic solution (group B). We studied lactate dehydrogenase (LDH) in the effluent fluid of coronary sinus and ultrastructure of myocardial cells. No statistically significant difference in LDH release activity was observed between group A and group B during heart arrest perfusion, but it was evidently higher in group B than in group A during rewarming at 5, 10, 30, 45 min. Ultrastructure destructive changes of myocardium went alongside with the increase of release of the enzyme. After 45 min of rewarming perfusion, group A hearts showed essentially normal ultrastructure, but those in group B showed evident swelling of mitochondria, vesiculation and fatty changes of cytoplasm, dissolution and fragmentation of myofibrils, etc. The experimental results indicate that FTPA cardioplegic solution offers better myocardial protection than does St. Thomas cardioplegic solution.

Based on two associations of hepatocellular carcinoma with lupoid hepatitis and 10 such cases reported in the literature, a pathological study was undertaken to compare this small group of patients with general population of lupoid hepatitis in terms of sex and age distribution, duration of illness and underlying liver pathology, etc., and to attempt to clarify the possible predisposing factors to the occurrence of hepatoma in these patients. 21 patients with lupoid hepatitis were found from 54 241 autopsies (0.04%). Four patients were male (19 %) and 17 female (81 %). The average age at autopsy was 41 years with a mean duration of illness of 4.2 years. The occurrance of two associations with hepatoma among lupoid patients constituted 9.5%. In contrast, 12 patients with hepatoma showed a higher male/ female ratio of 4/6, a mean age of 59 years and a mean duration of illness of 16 years. The above data indicate that maleness and older age with long duration of disease in patients with lupoid hepatitis are more predisposed to the development of tumor. The possible mechanisms of carcinogenesis in these patients are discussed.