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The Cassegrain telescope system was design for space environment. The correct lens mount assembly is included as correct lens, lens mount, spacer, mount barrel and retainer. The system mass budget allocated to correct lens assembly was 5 Kg. Meanwhile, according to optical design the correct lens is made from fused silica, the lens diameter is 130 mm, and the mass is 2.3 Kg. Therefore, remain mass budget is 2.7 Kg; including the lens mount, spacer, mount barrel and retainer. The telescope system deformation is mainly caused by thermal deformation on space orbit. The correct lens mount was made from invar material in initial design. The CTE (Coefficient of Thermal Expansion) of invar is only 1* 10-6/°C, low CTE would be resistant to thermal deformation, but invar density is 8* 10-6kg/mm3. If all components were made from invar, the total mass was over 2.7 kg. Thus, the components material would consider titanium alloy (CTE is 8.6* 10-6/°C, density is 4.43* 10-6kg/mm3) or aluminum alloy (CTE is 23.6* 10-6/°C, density is 2.81* 10-6kg/mm3). The titanium alloy density is 1.83 times lighter than invar, but CTE is 8.6 times higher. The aluminum alloy density is 2.84 times lighter then invar, but CTE is 23.6 times higher. The lens mount thermal deformation would effect correct lens surface wavefront error and introduce optical aberration. This article analyzes the correct lens assembly thermal deformation and optical performance in different lens mount material. From above conditions, using FEM (Finite Element Method) and optical software, simulation and optimization on the lens mount design have been performed to achieve system mass requirement.

The effect of the acceleration force during launch on the primary mirror of a Cassegrain telescope has been studied in the paper. Finite element method and Zernike polynomial fitting are applied to the ZERODURRprimary mirror with a predesigned lightweight configuration on the back. The relations between several selected surface treatment conditions and the mirror characteristic strength as well as the safety factors under various launch accelerations have been investigated. It is found that the surface treatment on the mirror surface needs to be at least ground using a D251 or finer tool to keep the load safety factor of the primary mirror structure of the telescope higher than 1.5 aerially. In addition the principle strss difference of the lightweight ZERODURRmirror induced by the grinding process with an average grain size of 149 m is up to 1 MPa.

AbstractBackground/Aims: Left ventricular hypertrophy (LVH) has long been known as an independent risk factor for cardiovascular deaths, in both dialysis and general populations. Numerous factors influence the pathophysiology of LVH. However, extracellular fluid may have a particularly important influence on this impact. Inferior vena cava diameter (IVCD) estimation is a non-invasive and relatively convenient method for obtaining a good correlation with the intravascular fluid status, and may obtain an optimal dry weight (DW) for chronic hemodialysis patients. This study estimates the DW of end-stage renal disease (ESRD) patients by echocardiographic measurement of the IVCD to observe changes in cardiac morphology and function. Methods: A total of 88 patients, ranging from 26 to 90 (59.4 ± 13.3) years of age, were involved in this study. The patients were divided into study (n = 48) and control (n = 40) groups. All patients received IVCD assessment via echocardiography bi- monthly for 1 year. In the study group patients, DW was adjusted according to the IVCD by echocardiography. Meanwhile, in the control group patients, DW was adjusted based on traditional clinical parameters. All patients underwent cardiac examinations and measurements, including left ventricular mass (LVM), wall thickness, chamber size and left ventricular systolic function by echocardiography, at the beginning and end of the study. Results: Both groups displayed comparable clinical and biochemical parameters. The IVCD index correlated well with the cardiac parameters estimated by echocardiography. The LVM and left ventricular mass index (LVMI) was reduced significantly in the study group patients (from 200 ± 64.2 to 187 ± 63.2 g, p = 0.021; from 132 ± 37.6 to 123 ± 37.3 g/m2, p = 0.014, respectively). Furthermore, the study group patients with fluid overload, named study subgroup A, displayed significant differences not only in LVM and LVMI, but also in septal wall thickness, left ventricular end-diastolic dimension and left atrial dimension. In contrast, the control group displayed no changes in these cardiac architectures during the study period. Conclusion: Adjusting DW via the IVCD measured by echocardiography for hemodialysis patients may prevent the progression of chamber dilatation and LVH, especially for patients with fluid overload.Copyright © 2004 S. Karger AG, Basel

AbstractBackground/Aims: Ideal dry weight (DW) can serve as a marker of good quality of life (QOL) in patients receiving chronic hemodialysis. The size of the inferior vena cava (IVC) reflects the intravascular fluid status, and the diameter of IVC correlates indirectly with DW in these patients. Adjusting DW using echocardiographic measurement of the diameter of the IVC thus may be useful in maintenance of a better QOL in patients receiving chronic hemodialysis. Methods: This study included 119 patients with ages ranging between 27 and 90 years (mean ± standard deviation of 58.3 ± 12.8). All of the patients received the IVC diameter (IVCD) measurement by echocardiography every 2 months for 1 year. The study group included 68 patients in whom the DW were adjusted by echocardiographic measurement of the IVCD, while the control group included 51 patients in whom the DW was adjusted by the conventional method. QOL was evaluated using the short form 36 questionnaire (SF-36) at the beginning and at the end of the study. Besides, the Kt/Vurea value, a parameter of total urea clearance, was measured at the beginning and at the end of the study in patients of both groups. Results: The scores of physical functioning, physical role functioning, general health and physical component summary showed a prominent improvement in the study group but not in the control group. The impact of periodic echocardiographic evaluation also demonstrated a significant change in the scores of physical functioning, physical role functioning and physical component summary in the study group. Furthermore, the Kt/Vurea value, a parameter of total urea clearance, also increased significantly in the study group. Conclusion: Ideal DW is better adjusted by periodic echocardiographic measurement of the IVCD in patients undergoing chronic hemodialysis. Maintenance of a better DW leads to improve hemodialysis quality and QOL in these patients.Copyright © 2004 S. Karger AG, Basel

There has been a recent upsurge of interest in mushrooms as a source of biological active compounds of medicinal value including anti-cancer, anti-viral, immunopotentiating, hypocholesterolaemic and hepatoprotective agents. This new class of compounds, termed ‘mushroom nutriceuticals’, are extractable from either the fungal mycelium or fruiting body and represent an important component of the expanding mushroom biotechnology industry.

One of the most economically-viable processes for the bioconversion of many types of lignocellulosic wastes is represented by edible mushroom cultivation. Lentinula edodes, Volvariella volvacea and Pleurotus sajor-caju are three important commercially cultivated mushrooms which exhibit varying abilities to utilise different lignocellulosics as growth substrate. Examination of the lignocellulolytic enzyme profiles of the three species show this diversity to be reflected in qualitative variations in the major enzymic determinants (i.e. cellulases, ligninases) required for substrate bioconversion. For example, L. edodes, which is cultivated on highly lignified substrates such as wood or sawdust, produces two extracellular enzymes which have been associated with lignin depolymerisation in other fungi, (manganese peroxidase and laccase). Conversely, V. volvacea, which prefers high cellulose-, low lignin-containing substrates produces a family of cellulolytic enzymes including at least five endoglucanases, five cellobiohydrolases and two ß-glucosidases, but none of the recognised lignin-degrading enzymes.

Pleurotus sajor-caju was generally more tolerant to lignin-related phenolic monomers and tannin derivatives than Lentinus edodes and the straw mushroom, Volvariella volvacea. Several phenols, at up to 5 mM, enhanced mycelial growth of P. sajor-caju. No clear pattern was evident when the effects of phenols and tannins on the growth of V. volvacea and L. edodes were compared, but the lower concentrations of 4-hydroxybenzaldehyde and vanillin which were tested were markedly more toxic to the straw mushroom. The distribution of phenolic monomers and tannin derivatives in the agricultural wastes used for mushroom cultivation may be an important growth determinant. However, the differences in the growth inhibition profiles of L. edodes, P. sajor-caju and V. volvacea suggest that, alone, the effect of these compounds on fungal growth is unlikely to account for the varying abilities of the three mushroom species to grow and fruit on a particular lignocellulosic substrate.

Two irreversible inhibitors, iodoacetamide and diethylpyrocarbonate, were used to select intraspecific fusion products of two mushroom species, Coprinus cinereus and Schizophyllum commune. Iodoacetamide was the more suitable inhibitor because it gave a low breakage frequency and low survival rate of the cells in the inactivation experiments. Fusion-induced by polyethylene glycol and electro-fusion were compared and, under optimal conditions, gave fusion frequencies of 16.7% to 50.0% and 6.9% to 8.4%, respectively. All fusion progeny were heterokaryons (dikaryons) and had clamp connections. There were no differences in the morphology and fruiting ability of the fusion progeny and those of the heterokaryons generated from mating.

A method for the cultivation of Pleurotus sajorcaju on a relatively large scale using cotton waste as substrate has been developed, and the mushroom so obtained has higher protein content than and comparable carbohydrate content to Agaricus bisporus, Volvariella volvacea, Lentinus edodes and Pleurotus ostreatus. The crude fats, ash, energy value, vitamin and mineral contents are lower and yet the differences are not great. The biological efficiency from cotton waste compost is lower than that from straw compost, however, the former has the advantage of giving rather even yield over successive flushes. This mushroom has a high potential to be produced economically on a large scale in Hong Kong.

A reduction of post-weld shift (PWS) in semiconductor laser packaging using a laser welding technique is presented. It is found that the PWS and its association with the power coupling loss of the laser packaging can be reduced under proper pressure constraint. Characteristics of defect mechanisms in laser welding techniques for semiconductor laser packaging are also investigated experimentally. The results in the stainless-to-Kovar joints show that the surface cracks are dependent on the Au thickness on the Kovar material. The low solubility of gold in the Kovar is identified as the defect mechanism for surface cracks. Preliminary reliability data demonstrated that these laser packages without crack defects in the welded joints are reliable.

The Regional Network for Microbiology in Southeast Asia is one of the programmes for regional cooperation in the basis sciences established by UNESCO in collaboration with the government of Japan through a funds-in-trust agreement, in 1974. Up to 1991, the network has organized 50 scientific activities and 945 young microbiologists have received training in microbiology. The nature of the programme's activities has become more specific recently and concerns microbial resources and use of biotechnology to conserve the environment.

The association of misfolded proteins, or aggregation, is a critical problem in a number of human diseases as well during the expression, refolding, formulation, and delivery of therapeutic proteins. In this study, we investigate lysozyme precipitation with hydrogen exhange using nuclear magnetic resonance (NMR) and mass spectrometry (MS). We show that MS can reveal the presence of conformational distributions, albeit without the detailed structural information afforded by NMR. Further, we find that increases in precipitant concentration alter the structure and composition of precipitates. The selective unfolding of one portion of the protein in these precipitates is correlated with hydrogen exchange patterns observed under nonprecipitating conditions and in other studies of lysozyme.