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Lymphoepithelioma-like carcinoma (lelc) is a rare malignancy in ocular adnexa. Here, we report 4 patients with lelc and review 11 patients reported in the literature. Clinical profiles, association with Epstein&ndash, Barr virus (ebv), treatment, and outcomes are analyzed. Lacrimal glands and the lacrimal drainage system, eyelid, and conjunctiva are potential primary sites for lelc. The tumours are characterized histologically by nests of undifferentiated malignant cells surrounded by lymphoid infiltrates. Infection with ebv was confirmed in lelc of ocular adnexa, and that association seemed to be restricted to Asian populations. Results from our centre uniformly showed expression of ebv-encoded small rnas in primary tumour, locally recurrent tumour, and metastatic lymph nodes. This disease had a tendency to relapse regionally. Postoperative radiotherapy seems to improve disease-free survival. Tumours appear to be sensitive to radiotherapy and chemotherapy based on cisplatin and 5-fluorouracil. At our centre, 3 patients were still living at 22, 33, and 76 months after surgery. One patient died of distant metastasis after a survival of 38 months. Lymphoepithelioma-like carcinoma is a heterogenous entity among ocular adnexal malignancies. Multimodality treatment provides a better chance at survival. Further investigation is required to achieve a better understanding of the biologic behavior of this entity and of its optimal treatment.

Polycrystalline ZnO/La0.7Sr0.3MnO3 (LSMO) heterostructures were fabricated onto Si(100) substrates by magnetron sputtering. A rectifying behavior, as well as an enhanced magnetoresistance (MR) ratio (∼ 12%), was obtained in the heterostructure with respect to the LSMO single layer (a MR ratio ∼ 6%). The degradation of the rectifying behavior for the LSMO layer thinner than 20 nm is mainly due to the change in hole concentration. We suggest a possibility that the magneto-transport and the magneto-optical properties of manganites can be modified by the formation of this kind of heterostructure. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In fabrication of free form optical surfaces, spot exposure is a typical mode in laser photolithography. Proper selection of spot exposure superposing ratio is the key to optimize etching quality and writing speed. In this paper, a new composite diffractive grating structure is modeled for the influence on diffraction efficiency of binary optical elements caused by spot exposure superposing ratio. Composite grating can be transformed into one simple rectangular grating and two triangular gratings. Angular spectrum theory is used to describe the mathematical expression of the composite diffractive grating. Through simulation analysis, the relationships between diffraction efficiency and the other three items as grating depth, spot radius, and blaze wavelength, has been shown. Simulation results indicate that shape error caused by spot exposure ratio impact the diffraction efficiency greatly in deep etching, and the transmittance will reach maximal point approximately while spot exposure ratio is over 60%. This conclusion can be taken as the theoretical foundation for exposure frequency selection in laser photolithography figure generation.

In this paper, an experimental study of the heat transfer characteristics of a tube-and-fin radiator for vehicles is carried out by using an experimental optimization design technique on a wind tunnel test rig of the radiator. The regression equations of heat dissipation rate, coolant pressure drop and air pressure drop are developed. The influences of the air velocity, inlet coolant temperature and volume flowrate of coolant on heat dissipation rate, coolant pressure drop and air pressure drop are discussed in detail by means of the numerical analyses. Also, the research results provide a basis for the theoretical analysis of heat performances and structural refinement of the tube-and-fin radiator.

Measured and calculated (without any adjustable material parameter) electron Hall mobility and carrier concentration in the range of 26.5–273 K are reported for a high-mobility free-standing bulk GaN grown by hydride vapor phase epitaxy. The peak electron mobility of 7386 cm 2 /V s at 48 K and a value of 1425 cm 2 /V s at 273 K were measured. An iterative solution of the Boltzmann equation was applied to calculate the mobility using the materials parameters either measured on the sample under study or recent values that are just becoming available with only the acceptor concentration being variable. Using only one donor and one conducting layer system, the donor and acceptor concentrations of 1.76×10 16 and 2.4×10 15 cm −3 , respectively, satisfy simultaneously the charge neutrality and electron mobility at all temperatures within the framework of the iterative method and measurements. The donor activation energy was determined to be 25.2 meV and is consistent with the value of about 30 meV for the hydrogenic ground state in a dilute semiconductor. The high electron mobility, low background impurity concentration, low compensation ratio, and negligible dislocation scattering demonstrate the high quality of the material studied.

For better anatomic and physiologic fitting, a novel implantable aortic valvo-pump (IAVP) has been developed. A valvo-pump is a micro axial flow impeller pump, which has the same dimensions and function, as well as the same location, of a valve. Therefore, IAVP needs no inlet and outlet tubes, no additional anatomic occupation, and has less physiologic disturbance to natural circulation compared with the traditional bypass left ventricular assist device (LVAD). The device has a stator and a rotor. The stator consists of a motor coil with an iron core and an outflow guide vane; the rotor includes driven magnets and impeller. There is neither bearing nor strut in both the pump and the motor. In order to reduce the attractive force between the rotor and the stator, so as to enhance the durability of the performance, the rotor magnets were minimized without reducing the driving torque and efficiency of the motor. The impeller vane was designed according to a three-dimensional and analytical method, for preventing stasis and turbulence. The largest outer diameter is 24.7 mm and the length at this point is 12.4 mm. The total weight is 40 g (including the rotor of 11 g). The consumed power is 7 W (14 V x 0.5 A) at 15 000 rpm. This rotating speed stays unchanged during haemodynamic testing together with a pulsatile centrifugal pump, which imitates a failing ventricle. The maximal flow cross IAVP reaches over 10 l min(-1) and the pressure head at 0 l min(-1) can be as large as 80 mmHg. At flow rate of 4 - 8 l min(-1), IAVP enlarges the flow c. 1 l min(-1) and meanwhile increases the pressure about 10 mmHg. The pressure pulsatility generated by the pulsatile centrifugal pump remains 40 mmHg after passing IAVP. By first animal experimental trial the device was sewed in aortic position of an 80 kg pig without harm to adjacent tissue and organs. IAVP promises to be a viable alternative to natural donor heart for heart transplantation in the future.

In order to predict the interior noise of the automobile in the low and middle frequency band in the design and development stage, the hybrid FE-SEA model of an automobile was created using hybrid FE-SEA method. The modal density was calculated using analytical method and finite element method; the damping loss factors of the structural and acoustic cavity subsystems were also calculated with analytical method; the coupling loss factors between structure and structure, structure and acoustic cavity were both calculated. Four different kinds of excitations including road excitations, engine mount excitations, sound radiation excitations of the engine, and wind excitations are exerted on the body of automobile when the automobile is running on the road. All the excitations were calculated using virtual prototype technology, computational fluid dynamics (CFD), and experiments realized in the design and development stage. The interior noise of the automobile was predicted and verified at speed of 120 km/h. The predicted and tested overall SPLs of the interior noise were 73.79 and 74.44 dB(A) respectively. The comparison results also show that the prediction precision is satisfied, and the effectiveness and reliability of the hybrid FE-SEA model of the automobile is verified.

With the fast development of subways, tunnels, and high-rise buildings in Shanghai in the past 10 years, jet grouting technology has been widely used in various projects which also further promote its development. In addition to the single, double and triple pipe methods, an engineering method similar to RJPI has been used. The treatment depth has increased to approximately 50m from 20-30m The main objectives of using jet grouting technology in the above projects are: foundation reinforcement and formation of water insulation curtain. Since soil 1ayers in Shanghai are soft, adopting jet grouting technology to form vertical or horizontal water-resisting bodies of different depths and thicknesses has become an important means to achieve this purpose. In combination with the actual examples of application, this paper presents the status of jet grouting applications in Shanghai area in the past 10 years and looks into the prospects for technological developments in the future.

Fifty-nine patients with idiopathic growth hormone deficiency were included in a Chinese multicentre trial of recombinant somatropin, 0.5-0.7 IU/kg/week s.c. given in six or seven divided doses. The height velocity increased from 2.8 +/- 1.0 cm/year to 13.1 +/- 2.5 cm/year during 1 year of treatment, and typical catch-up growth was observed. The increase in height SDS for chronological age was significant, but the increase in height SDS for bone age was not statistically significant. No adverse reactions to the treatment were recorded. Recombinant somatropin was shown to be very effective and safe during the first year of therapy in patients with growth hormone deficiency.

Photoenhanced electrochemical (PEC) etching in an unstirred KOH solution under He–Cd laser illumination was used for delineating extended defects in GaN films. When a low-excitation intensity was employed, the process yielded threading vertical features at dislocation sites. Application of an external voltage or a higher-illumination intensity led to high-etch rates with smooth surfaces. Some highly resistive samples, for which no etching was obtained under normal etching conditions, could be etched with the application of a single-polarity external voltage. Finally, in a GaN sample with an AlN/GaN superstructure inside, high selectivity between AlN and GaN was achieved; in this case, the PEC process stopped at the thin AlN stop layer.

Zn0.96Mn0.04O∕ZnO coaxial nanocable and Zn0.96Mn0.04O film were prepared by two-step method and magnetron sputtering, respectively. The x-ray diffraction analysis reveals that Mn is incorporated well into the wurtzite ZnO without formation of Mn or Mn oxide. The high resolution transmission electron microscopy image and the selected-area electron diffraction pattern demonstrate that both ZnO and Zn0.96Mn0.04O layers are single crystalline and an epitaxial growth is achieved between Zn0.96Mn0.04O and ZnO in the coaxial nanocable. The magnetic property measurements show that both Zn0.96Mn0.04O∕ZnO nanocable and Zn0.96Mn0.04O film are ferromagnetic at room temperature. Moreover, the saturated magnetization and the coercive field of Zn0.96Mn0.04O∕ZnO coaxial nanocable are larger than those of Zn0.96Mn0.04O film.

The 200‐MeV electron linac at the Hefei National Synchrotron Radiation Laboratory (HESYRL) is described. It is not only an injector of the 800‐MeV storage ring, but an electron accelerator used for nuclear physics experiments and some other applications as well. The main design parameters and measuring results of the LINAC are given. The linac is a travelling wave structure, operating at a frequency of 2856 MHz, constant impedance, in a 2/3π mode. Its total length is about 35 m. Five klystrons are used as rf power; each klystron will provide 15 MW. In November 1987, the machine was successfully commissioned and typical operating parameters are 220 MeV, and 50 mA with an energy spread of ±0.8%.

The use of a laser-Doppler anemometer to measure velocities in a fluid with a larger variation in its refractive index perpendicular to the laser beams may introduce appreciable errors. This situation is commonly encountered in convective heat transfer studies. The beams are refracted as they pass through the fluid and the distance of the intersection of the beams, control volume, from the surface may be significantly different than the distance of the beams from the surface when they entered the fluid. If the flow is unsteady or turbulent, the relative movement of the beams may be such that the size and location of the control volume is constantly changing causing appreciable errors.

Photoenhanced electro-chemical (PEC) wet etching has been shown to be suitable for dislocation-density estimation in n-GaN films as well as for GaN-based device fabrication. We report on PEC etching of n-GaN samples grown by MBE and HVPE methods in unstirred aqueous KOH solution under He-Cd laser illumination. Characterization of the etched samples was carried out using atomic force microscopy (AFM) in both cross-sectional and plan-view configurations and scanning electron microscopy (SEM). At moderate illumination densities, the SEM and AFM analyses reveal sub-100 nm scale threading vertical wires on the etched surfaces. The calculated density (∼1×10 9cm−2) is in agreement with dislocation density found by transmission electron microscopy. Using cross-sectional AFM, we find that these vertical wires are ∼1[.proportional]m high and are perpendicular to the sapphire surface. Applying a higher illumination density or an external voltage, we obtain a higher etch rate with a smooth free-feature etched surface. Some highly resistive samples that cannot be etched under normal conditions because the band bending is too small to confine the holes to the surface for them to participate in the PEC process, can be etched with the application of a voltage to the sample. In this case, the etch rate depends on both the polarity and the magnitude of the voltage applied. In an MBE-grown sample with an AlN/GaN superstructure inside, we report on high selectivity between AlN and GaN (AlN is an etch stop); the selectivity is due to the etching mechanism of the PEC process.

The structural quality of the buffer layer juxtaposed to the substrate is pivotal in attaining high quality GaN layers. In MBE deposition, low temperature, medium temperature and high temperature AlN buffer layers are at the disposal of the grower. There are quite a few reports, some discussing the benefits of high temperature buffer layers and others doing the same for low temperature buffer layers. The reports emanate from different laboratories; and due to stringent parameter control required, it is difficult to compare one type of buffer with another. To gain some insight, we undertook an investigation wherein these varieties of buffer layers were grown on nitridated sapphire substrate under similar conditions for a comparative analysis. In addition to the single buffer layers of both GaN and AlN varieties, some combinations of stacked buffer layers, including cases where these buffer layers were separated by GaN layers, were employed. Structural analysis by high resolution X-ray diffractometry and topological analysis by AFM were carried out to assess the quality of the epilayers grown on these buffers. Hall measurements at room temperature were carried out to characterize the electrical transport properties.