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ABSTRACT Bacterial-based self-healing is a promising solution for sustainable concrete maintenance. In this study, bacterial spores were first encapsulated into hydrogels and then were incorporated into specimens to investigate their [...]

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High intensity power ultrasound was respectively introduced into three different solidification stages of Al–8%Si hypoeutectic alloy, including the fully liquid state before nucleation, the nucleation and growth process of primary α(Al) phase and L → (Al) + (Si) eutectic transformation period. It is found that both the primary α(Al) phase and (Al + Si) eutectic structure were refined by different degrees with various growth morphologies depending on the ultrasonic treatment stage. Based on the experimental results, the cavitation-induced nucleation due to the high undercooling caused by the collapse of tiny cavities was proposed as the major reason for refining the primary α(Al) phase. Meanwhile, obvious eutectic morphological change was observed only when ultrasound was directly introduced in the eutectic transformation stage, in which typical divorced eutectics and (Al + Si) eutectic cells with symmetrical flower shape were formed at the top of the alloy sample. The introduction of ultrasound in each solidification stage also improves the yield strength of Al–8% Si alloy to a diverse extent. [ABSTRACT FROM AUTHOR]

By using the first-principles calculation, we studied the mechanisms of point defects in Y4Al2O9 (YAM), a promising ternary oxide with excellent optical and thermal properties. It is found that the predominant native defect species is closely dependent on the chemical potentials of each constituent. In the case of O-rich condition, the oxygen interstitial has the very low defect formation energy, followed by the anti-site defects and Al vacancy; in the case of Al-rich condition, the oxygen vacancy yields the lowest defect formation energy, followed by the anti-site defects and Al interstitial. The present result shows that in all the possible chemical potential ranges, anti-site defects have relatively low defect formation energy and might exist in high concentration in YAM. Furthermore, AlY anti-site has relatively lower defect formation energy than the YAl anti-site throughout. The behaviors of defect complexes under non-stoichiometric condition, such as the Al2O3 or Y2O3 excess, are also investigated. The results provide helpful guide to optimize the experimental synthesizing of YAM. [Copyright &y& Elsevier]

The transport properties of polycrystalline La0.9Sb0.1MnO3 (LSMO) bulk prepared by the solid-state reaction were investigated. We find that transport behaviors heavily depend on the synthesis process. The resistivity of LSMO1 for less rubbing time shows one metal-insulator transition (MIT) peak at temperature of 201 K, while the resistivity of LSMO2 for more rubbing time shows a MIT and a shoulder at about 240 and 140 K, respectively. The magnetoresistance (MR) ratio of LSMO2 reaches 41% under magnetic field of 2 T. Moreover, the MR ratio keeps significant value within broad temperature range. The infrared (IR) absorption spectra of LSMO2 show that the stretch-mode peak split into two Gaussian peaks with the gap about 70 cm-1. This large splitting indicates there are strong distortion and disorder in LSMO2 sample. The results are interpreted in terms of the disorder system and phase separation in perovskite manganites.

Abstract: Coastal flow involves surface wave propagation, current circulation, and seabed evolution, and its prediction remains challenging when they strongly interact with each other, especially during extreme events such as tsunami and storm surge. We propose a fully coupled method to simulate motion of wave-current-seabed systems and associated multiphysics phenomena. The wave action equation, the shallow water equations, and the Exner equation are respectively used for wave, current, and seabed morphology, and the discretization is based on a second-order, flux-limiter, finite difference scheme previously developed for current-seabed systems. The proposed method is tested with analytical solutions, laboratory measurements, and numerical solutions obtained with other schemes. Its advantages are demonstrated in capturing interplay among wave, current, and seabed; it has the capability of first-order upwind schemes to suppress artificial oscillations as well as the accuracy of second-order schemes in resolving flow structures. [Copyright &y& Elsevier]

To identify structural connectivity change occurring during the first 6 months after traumatic brain injury and to evaluate the utility of diffusion tensor tractography for predicting long-term outcome.

First-line treatment of metastatic colorectal cancer with combinations of cetuximab and irinotecan-based or oxaliplatin-based chemotherapy has shown promising efficacy. The clinical response to such treatment is generally assessed by tumor measurement through imaging. This study was performed to evaluate the correlation between serial changes in imaging results and carcinoembryonic antigen (CEA) levels. In 64 patients with metastatic colorectal cancer receiving cetuximab plus FOLFIRI or FOLFOX-4 chemotherapy we retrospectively analyzed the relationship between changes in serum CEA and changes in imaging results throughout the treatment course. Response in terms of serum CEA change was defined as a ≥50% drop in CEA level for more than 4 weeks. The sensitivity and specificity of serum CEA changes after targeted chemotherapy in relation to imaging results were 80.5% (33/41) and 73.9% (17/23), respectively, with a diagnostic accuracy of 78.1% (50/64). The progression-free survival time of responders assessed by serum CEA change was significantly longer than that of nonresponders (p=0.0091). Our results highlight the importance of serum CEA monitoring in assessing the response to targeted chemotherapy and in predicting the prognosis of patients with metastatic colorectal cancer.

This paper describes the application of an object-oriented (OO) modelling concept and OO programming mechanisms to develop an activity object-oriented (AOO) simulation strategy for modelling construction operations. The AOO simulation strategy considers construction activities to be objects, thus overcoming some pitfalls due to the general simulation strategies in developing simulation models or controlling simulation experiments. This paper also discusses the characteristics and related problems of some simulation strategies used for construction simulation. Moreover, the AOO graphical modelling interface associated with the AOO simulation strategy is described. Finally, the AOO simulation system has been compared with other simulation tools.

Abstract: The effects of grain orientation and surface wetting on wood densification by compression in a hot press were evaluated for two commercial Canadian wood species, balsam fir (Abies balsamea) and black spruce Picea mariana. The vertical density profiles (VDP) of wood densified at 180 °C could be engineered to achieve different properties depending on press closing rate, wood permeability and annual ring orientation. The lower permeability of spruce caused it to split frequently during hot pressing. For balsam fir, at a press closing time of 2 min, the compressed wood with an original grain angle of 0° (radial compression) shows widened high density bands due to collapse of low density earlywood adjacent to the dense latewood. All grain orientations show higher density areas close to the wood surfaces similar to those of wood-based composites. However, when wood was preheated without pressure for 5 min followed by a press closing time of 2 min, water migrated to and plasticized the board centre causing it to be densified while the surface density remained low. Wood surface plasticizing with water or urea solution causes some localized surface densification, but the effect was not great.

Abstract: This paper focuses on the moisture properties of wood treated in palm oil-, soy oil- and slack wax for different processing times and temperatures. Also, the relative importance of oil uptake and thermal modification on the wood moisture properties is investigated. Slack wax was better than palm oil or soy oil in improving the moisture performance of thermally treated wood, and treatment at 220 °C was superior to treatment at 200 °C, with 4 h being generally better than 2 h treatment. Water absorption in samples treated with wax at 100 °C or 160 °C was similar to that in samples treated at high temperatures while improved anti-shrink efficiencies (ASE) and lower hygroscopicities occurred only for the high temperature treatments. Chloroform extracted samples treated at high temperature with palm oil or soy oil had relatively similar hygroscopicity and ASE properties compared to unextracted samples, but had greatly increased water absorption properties. These results confirm that chemical reactions in wood resulting from the heat treatment account for the main improvements of wood properties in reduced hygroscopicity and improved dimensional stability, while the oil absorbed by wood reduces the rate of water absorption.

How to dispose and recycle the waste appliances properly and correctly is widely considered to be the focus in modern society. As to this case, in the paper, recycling methods, recycling processes, recycling apparatus and the integration of appliance recycling information have been studied according to different kinds of waste appliances, and finally an integrated appliances recycling management information system (ARMIS) is established based on the ideas studied. The system is an applied software, which is the integration of product information management, recycling process management and recycling product data management, and its purpose is to help recycling enterprises overcome the deficiency of information and management experience in the course of recycling, improve the recycling efficiency of the waste appliances and set a guideline for the operation and management of recycling enterprises.

Objectives. To investigate the clinical characteristics of patients with tuberculous myositis.
Methods. From January 1996 to March 2001, patients with positive cultures of Mycobacterium tuberculosis or histology-proven caseous granulomatous inflammation from muscular specimens were identified and their medical records were reviewed.
Results. Thirty-five patients were identified. Infection-related myositis was initially suspected in 20 patients (57.1%). The routes of infection were contiguous spread in 22 patients (62.8%), haematogenous spread in 10 (28.6%) and traumatic inoculation in three (8.6%). Five patients (14.3%), including the three who had received corticosteroids, died of uncontrolled sepsis. The computed tomography or the magnetic resonance imaging of the involved muscles showed findings suggestive of tuberculous myositis in 15 patients (42.9%).
Conclusions. Tuberculosis should be considered as one of the possible aetiologies of myositis, especially among patients with suggestive radiographic findings or in endemic areas of tuberculosis. Patients who develop tuberculous myositis after using corticosteroids have poor prognoses.

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The Georgia Basin is one of the most hydrologically complex areas of Canada. Variations in temperature, precipitation and elevation influence the amount and form of water that drives streamflow in its rivers and streams. Climate change could have major regional effects on air temperature, precipitation, evapotranspiration, and ultimately runoff. In previous work, zones of homogenous hydrologic processes were delineated within the basin. Watersheds were separated into three types: rainfall-driven streams, snowmelt-driven streams, and hybrid (mixed rainfall- and snowmelt-driven) streams. Climate change was shown to have major regional effects on each type of watershed, affecting the amounts and patterns of runoff. In the current study we consider changes in extreme hydrologic events, floods and low flows, in these watersheds. Climate data downscaled from the Canadian Coupled General Circulation Model for future time periods are used as inputs to a hydrologic model optimized for mountain watersheds. The discrepancies between observed and modelled streamflows are examined. While the model reproduces central tendency measures well, there are significant biases in the ability of the models to reproduce extremes. Output from the hydrologic model is used to assess relative changes in the frequency, timing, and magnitude of floods and low flows between present and future (2020, 2050 and 2080) climate scenarios. The models suggest that frequency of floods will increase in all watersheds under the projected climate scenarios. In rainfall-driven streams, flood events increase in number, but not in magnitude. In hybrid streams, winter events occur more often while summer snowmelt flood events occur less often. In snowmelt-driven streams, the magnitude and duration of summer floods increase. Low flows in rainfall-driven streams maintain the same frequency and magnitude but occur over an extended period of time during summer. Hybrid streams show an increase in frequency, a decrease in magnitude, and a shift in time of occurrence of low flows to summer rather than winter. In snowmelt-driven streams, low flow events occur less often largely moderated by increased flow due to an overall increase in winter streamflow in a warmer climate.

Nd-doped yttrium aluminum borate, NdxY1—xAl3(BO3)4 (NYAB), with large sizes and good optical quality has been grown by the flux method. When the Judd-Ofelt (JO) theory of parity-forbidden electric-dipole transitions of rare earth ions on non-centrosymmetric sites was applied to NYAB, it resulted in a good fit on absorption of the crystal. According to the JO theory, the fitted intensity parameters Ωt (t = 2, 4, and 6) were calculated as 2.19 × 10^—20, 1.97 × 10^—20, and 3.10 × 10^—20 cm², respectively, with a root mean square deviation of 1.22 × 10^—21 cm². The emission properties of the excited ⁴F3/2 state have been studied, and the spectral parameters of NYAB crystal were compared with those of NdxGd1—xAl3(BO3)4 (NGAB) crystal. A cw NYAB laser at 1.06 μm end-pumped by a high-power diode laser array has been demonstrated. A maximum output of 3.2 W at 1.06 μm has been achieved with an optical conversion efficiency of 29.1% and an average slope efficiency of 37.5%. It is found that these results approach those of Nd : YVO4 crystal.

The cluster formations in solid–liquid interface boundary layers of KDP crystals have been studied by Raman spectroscopy and ab initio cluster calculations with the density-functional theory. The calculations are made on H2PO4, H4P2O8, and H4P4O16 clusters, which model the cluster structure in different growth layers. Excellent agreement has been achieved between vibrational frequencies predicted by theory and those observed in experiments. The present results also show that the desolvation process of polymer clusters takes place within the characteristic boundary layers. The growth unit of crystal growth is identified as H4P2O8 dimer cluster.

Joint immobilization is associated with altered cartilage biosynthesis and catabolism that may affect cartilage mechanics and joint function. In this study, the mechanical behavior of articular cartilage was studied in an experimental model of joint immobilization, in which the canine knee was cast-immobilized at 90° of flexion for 4 weeks. Articular cartilage from the medial tibial plateau was tested in compression and in shear. Biochemical assays for water and glycosaminoglycan content and histomorphometric grading were performed on site-matched samples. Significant decreases in the equilibrium and dynamic shear moduli, but not compressive moduli, were observed in cartilage after 4 weeks of joint immobilization as compared to cartilage from a separate control population. Importantly, there was also evidence of a decrease in the compressive and shear moduli of tibial cartilage from the contralateral knee joints compared to control joints that were not immobilized. No significant effect of immobilization on the biochemical parameters or histomorphometric scores was detected, expect for a significant loss of proteoglycan staining following immobilization. These findings for changes in the tibial cartilage following cast immobilization are consistent with a mild form of cartilage degeneration.

Yttrium calcium oxoborate (YCOB) and Nd:YCOB crystals of high optical quality and large dimension have been grown by the Czochralski method. Measurements of refractive indices have confirmed that these crystals were negative biaxial. The absorption spectra were determined and the various spectrum parameters were calculated. Polarized absorption spectra revealed the strong anisotropic character of Nd:YCOB. Raman spectra indicate that the nonlinearity of the crystal is mainly attributed to planar BO3triangles in the structure rather than to a distortion of oxygen octahedra.

The new phase formation in the system with nominal composition (Y1−xScx)A2(Cus3−yMy)Oz(A=Ba or Sr, M=W, Fe) is studied in detail. A series of layered scandium cuprates ScSr2(Cu3−yFey)Oz, ScBa2(Cu3−yFe)Oz(y≥1.5)and (Y1−xScx)Sr2(Cu1.5Fe1.5)O2(x=0.6)are synthesized successfully and are characterized by XRD and electron diffraction. These compounds have the same structure with 123 phases, but they show relatively large resistivities at room temperature under the present preparation conditions. The resistivity–temperature dependence shows semiconductor-like behavior.

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This report describes free transfer of transverse colon for reconstruction of the hypopharynx and cervical oesophagus. The transverse colon based on the middle colic vessels was used in three patients following laryngo-pharyngo-oesophagectomy for hypopharyngeal squamous carcinoma. There were no flap failures or intra-abdominal complications. Solid diet was well tolerated. Transverse colon is easy to harvest, has a long vascular pedicle, wide diameter and good ischaemic tolerance. Contrast studies showed it to be a wide bore passive conduit. Compared with currently available options these features may allow better outcome in pharyngo-oesophageal reconstruction and warrant further evaluation.

The growth defects in Nd:YCa4O(BO3)3 (Nd:YCOB) crystals were investigated by transmission synchrotron topography. It was found that growth striations were the primary defects in Nd:YCOB crystals. Grown-in dislocations, mosaic blocks and inclusions were also observed in the crystals. The effect of temperature field on the formation of growth defects in the crystals was discussed.

The growth twinning in self-frequency-doubling laser crystal NdxGd1—xAl3(BO3)4 (NGAB) has been observed with white-beam synchrotron radiation topography (WBSRT). It is shown that the growth twinning in flux-grown NGAB crystal is the 180° rotation twin in which the twofold symmetric operation axis is parallel to the [0001] direction and this kind of twinning often shows the black-and-white contrast in X-ray topography. It is believed that the growth twinning in NGAB was induced by growth bands formed during crystal growth.

The kinetics of the segregating element silver in the system Cu(111)(Ag) was measured at temperatures close to where the discontinuous transition in the silver surface concentration versus temperature occurs. The seemingly complex kinetic behaviour of two-step diffusion and anomalous segregation processes could be fitted using only the surface segregation energy ΔG, the surface interaction parameter ΩSand the bulk diffusion coefficient Dparameters.

Octahedral molecular sieves (OMS), doped with Ag+, Co2+, and Cu2+, have been tested for their catalytic activity for carbon monoxide oxidation at low temperatures for long times on stream. Metal loaded OMS materials are highly active for this catalytic reaction and compare favorably with other catalysts such as Hopcalite-like CuMn2O4catalysts, supported Ag catalysts, and supported noble-metal catalysts, especially with respect to resistance to deactivation in a long run. Co-doped OMS-2 has been tested for selective oxidation in the presence of a large surplus of hydrogen in the feed gas. This catalyst shows nearly exclusive oxidation of CO versus hydrogen with oxygen present in stoichiometric amounts with carbon monoxide. Its stability against reduction in CO or H2containing gas is demonstrated from comparisons of X-ray diffraction patterns and X-ray photoelectron spectra before and after exposure to these gases. Average oxidation numbers and populations of Mn valence states were determined for these catalysts. Catalytic activity of doped OMS catalysts toward CO oxidation shows a correlation among average oxidation number of Mn and the position and nature of the doped cation. The structure of the active sites and the mechanism of the reaction are proposed.

Tool flank wear is a major cause of thermal damage in the machined surface layer in finish hard machining. A new methodology is developed to provide the knowledge needed for understanding the heat transfer regarding the formation of the thermal damage and the cutting mechanics. The methodology consists of a thermal model based on Green's function and a microstructure-based method using orthogonal hard turning. The coupling of the interface boundary conditions due to chip formation and flank wear is resolved using the proposed microstructure-based method, which is a departure from the conventionally incorrect approaches based on the assumption of constant chip formation. By incorporating the microstructure-based method with the thermal model, heat generated, heat partition, and the shear forces at the tool-chip and tool-work interfaces can be determined. Interface temperatures that are extremely difficult to be measured are obtained. The results quantitatively explain how the heat transfer and chip formation are altered as the tool flank is progressively worn.

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The microstructure and high-temperature tensile properties of Fe–27A1 (in atomic percent) alloy have been investigated. Tensile tests are performed in a temperature range of 600–800°C in air under an initial strain rate of 1×1 10−4s−1. Important characteristics such as up to 300% elongation, strain-rate sensitivities of ∼ 0.3 and low flow activation energy confirm that our Fe–27A1 alloy with a coarse grain-size of ∼ 700–800μm exhibits superplasticity at temperatures at or above 700°C. The low flow activation energy, ∼ 250 kj mol−1, indicates the mechanism operating during the superplastic deformation is not likely controlled by the lattice diffusion. Our microstructural observations reveal several important features such as the low dislocation density, grain refinement, grain-boundary migration, cavity coalescence and grain-boundary cavity. The refined grain structure (∼ 100–200μm in size) is presumably attributed to the continuous grain-boundary migration, as evidenced by the presence of irregular curve-shaped grain boundaries. Interestingly, this strain-induced boundary migration might actually increase the surface energy, as opposed to the surface-tension-induced boundary migration that reduces the surface energy during a normal annealing process. Further studies are suggested in order to establish a better understanding of the mechanism for this grain-boundary migration and its roles on the superplasticity.

The effects of post-coating processing by means of flame, laser and vacuum furnace heating on the structure and erosive wear characteristics of flame and plasma spray coatings were studied. The results show that post-coating processing can modify the microstructure, reduce its porosity, increase its plasticity and toughness and improve the metallurgical bonding to the substrate. Therefore, the erosion resistence of these deposits is increased substantially and is even more significant when the erodent impact angle and impact velocity are higher. The mechanism of erosive wear has obviously changed from brittle to plastic erosion. The application of different spray methods and post-coating processing in terms of erosive wear was analysed and compared.

A universal intracellular factor, the ‘M phase‐promoting factor’ (MPF), triggers the G2/M transition of the cell cycle in all organisms. In late G2, it is present as an inactive complex of tyrosine‐phosphorylated p34cdc2 and unphosphorylated cyclin Bcdc13. In M phase, its activation as an active MPF displaying histone H1 kinase (H1K) originates from the concomitant tyrosine dephosphorylation of the p34cdc2 subunit and the phosphorylation of the cylin Bcdc13 subunit. We have investigated the role of cyclin in the formation of this complex and the tyrosine phosphorylation of p34cdc2, using highly synchronous mitotic sea urchin eggs as a model. As cells leave the S phase and enter the G2 phase, a massive tyrosine phosphorylation of p34cdc2 occurs. This large p34cdc2 tyrosine phosphorylation burst does not arise from a massive increase in p34cdc2 concentration. It even appears to affect only a fraction (non‐immunoprecipitable by anti‐PSTAIR antibodies) of the total p34cdc2 present in the cell. Several observations point to an extremely close association between accumulation of unphosphorylated cyclin and p34cdc2 tyrosine phosphorylation: (i) both events coincide perfectly during the G2 phase; (ii) both tyrosine‐phosphorylated p34cdc2 and cyclin are not immunoprecipitated by anti‐PSTAIR antibodies; (iii) accumulation of unphosphorylated cyclin by aphidicolin treatment of the cells, triggers a dramatic accumulation of tyrosine‐phosphorylated p34cdc2; and (iv) inhibition of cyclin synthesis by emetine inhibits p34cdc2 tyrosine phosphorylation without affecting the p34cdc2 concentration. These results show that, as it is synthesized, cyclin B binds and recruits p34cdc2 for tyrosine phosphorylation; this inactive complex then requires the completion of DNA replication before it can be turned into fully active MPF. These results fully confirm recent data obtained in vitro with exogenous cyclin added to cycloheximide‐treated Xenopus egg extracts.

In Philadelphia chromosome‐positive human leukemias, which include chronic myelogenous leukemia and some acute lymphocytic leukemias, the c‐abl proto‐oncogene on chromosome 9 becomes fused to the bcr gene on chromosome 22, and Bcr‐Abl fusion proteins are produced. The Bcr sequences activate the Abl tyrosine kinase which is required for the transforming function of Bcr‐Abl. The Bcr sequences also enhance an F‐actin‐binding activity associated with c‐Abl. Here, we show that binding of c‐Abl and Bcr‐Abl proteins to actin filaments in vivo and in vitro is mediated by an evolutionarily conserved domain at the C‐terminal end of c‐Abl. The c‐Abl F‐actin‐binding domain contains a consensus motif found in several other actin‐crosslinking proteins. Mutations in the consensus motif are shown to abolish binding to F‐actin. Bcr‐Abl proteins unable to associate with F‐actin have a reduced ability to transform Rat‐1 fibroblasts and to abrogate the requirement for interleukin‐3 in the lymphoblastoid cell line Ba/F3. In transformed cells, Bcr‐Abl induces a redistribution of F‐actin into punctate, juxtanuclear aggregates. The binding to actin filaments has important implications for the pathogenic and physiological functions of the Bcr‐Abl and c‐Abl proteins.

Exogenous epidermal growth factor (EGF) markedly increases the in vivo uptake of glutamine by small intestine during total parenteral nutrition (TPN). Since glutamine is the major oxidative fuel for the small intestine and is synthesized mainly in skeletal muscle, we investigated whether EGF would induce changes in the activity of the enzymes that mediate glutamine degradation (glutaminase) and synthesis (glutamine synthetase) in the two tissues. Male Sprague-Dawley rats were randomized into three groups: group I (chow) were fed rat chow and water ad libitum, group II (TPN) received a standard formula of TPN, and group III (TPN-EGF) received the same TPN as group II and injections of EGF (0.1 μg/gm body weight (bw)) subcutaneously twice daily. TPN was given for 2 wk; when EGF was administered along with TPN, the glutaminase activity of intestinal mucosa and the glutamine synthetase activity of skeletal muscle were increased, respectively, by 25% and 24% ( P < 0.05, versus TPN group). These data suggest a mechanism whereby EGF enhances the intestinal utilization of glutamine by changing the activities of glutamine metabolic enzymes in the small intestine and skeletal muscle during TPN.

The growth defects in flux-grown NdxY1 − xAl3(BO3)4(NYAB) single crystals have been investigated by means of chemical etching and synchrotron radiation techniques. The band-shaped and polysynthetic twins were detected by optical microscopy due to the difference in etching rates between the host crystal and the twin. In the meantime, the orientation and symmetry of the twins were analyzed from their etching patterns. A large number of etch pits with regular shapes were also found on the surface, and these etch pits correspond to outcrops of the dislocations originating from the seed crystal or inclusions.

A parallel implementation of Chebyshev method is presented for the B-spline surface interpolation problem. The algorithm finds the control points of a uniform bicubic B-spline surface that interpolates m× ndata points on an m× nmesh-connected processor array in constant time. Hence it is optimal. Due to its numerical stability, the algorithm can successfully be used in finite precision floating-point arithmetic.

Optical inhomogeneities and growth defects in flux-grown Nb-doped potassium titanyl phosphate crystals have been investigated. The growth striations, growth sector boundaries and dislocations are revealed by white-beam synchrotron radiation topography. All of the observed dislocations are growth induced and no ferroelectric domains are found in the crystals. It is believed that the main reason for causing the instability of the 90° non-critical phase matching along the x-direction is related to the growth striations, especially of {011} sectors.

Surfactant protein D is a collagenous C-type lectin (collectin) that is found almost exclusively in the lung. A recombinant protein, composed of the neck-region and the carbohydrate binding domain of bovine lung surfactant protein D, has been overexpressed in E. coli. The recombinant protein showed the same sugar binding specificity as the native protein and was able to bind to the lipopolysaccharides of several strains of Gram-negative bacteria, such as Klebsiella pneumoniae, Pseudomonas aeruginosaand Escherichia coli, which are known to cause lung infections. This binding was calcium-dependent and was inhibited by maltose. Native bovine surfactant protein D was also shown to be able to bind to these lipopolysaccharides in the same manner.

The v‐abl oncogene of Abelson murine leukemia virus (A‐MuLV) induces two opposite phenotypes in NIH3T3 cells. In the majority of cells, v‐abl causes a growth arrest at the G1 phase of the cell cycle; while in a minority of cells, v‐abl abrogates the requirement for growth factors. Using temperature sensitive mutants, it can be demonstrated that v‐Abl tyrosine kinase is required for growth inhibition or stimulation. The two phenotypes are not caused by mutations or differences in the expression of v‐Abl, but are dependent on the cell context. Two stable subclones of NIH3T3 cells have been isolated that exhibit similar morphology and growth characteristics. However, upon infection with A‐MuLV, the ‘positive’ cells become serum‐ and anchorage‐independent, whereas the ‘negative’ cells become arrested in G1. The positive phenotype is dominant, shown by cell fusion, and treatment with 5‐azacytidine converts the negative cells to the positive phenotype. Activation of v‐Abl tyrosine kinase induces the serum‐responsive genes in the positive but not in the negative cells. Transactivation of the c‐fos promoter by v‐Abl in transient assays is also restricted to the positive cells. These results show that v‐Abl tyrosine kinase is not an obligatory activator of growth, but requires a permissive cellular context to manifest its mitogenic function.

Formation of nonequilibrium δ-A15 Cr thin films prepared by sputter deposition has been studied. Among processing parameters examined, working pressure, deposition temperature, and time were found to play an important role in affecting the formation of δ-A15 Cr phase. Susceptibility of δ-A15 Cr formation to the processing condition was essentially ascribed to its metastable nature. Since it could irreversibly transform into the equilibrium α-BCC Cr upon heating, the nonequilibrium δ-A15 Cr became unfavorable to form under the processing conditions that led to significant increases in film surface temperature such as lengthy depositions or elevated deposition temperatures. During the lengthy deposition, the film surface temperature inevitably increased as a result of continuous energetic particle bombardmetns. Such film surface temperature increase was analogous to an in situ annealing that was detrimental to the formation of thicker δ-A15 Cr films. To minimize the in situ annealing effect, the deposition with prolonged intermissions has showed very effectively to grow the relatively thick Cr films that had the nonequilibrium δ-A15 crystal structure.

A series of manganese oxide molecular sieve (OMS) materials has been successfully synthesized. Doping some divalent cations and first row transition metal ions such as Mg2+, Ni2+, Cu2+, Co2+, and Fe3+into the framework of OMS materials to form [M]-OMS materials was also done. The catalytic activities of [M]-OMS materials and commercial MnO2for H2O2decomposition were studied. The experimental results show an activity order sequence as follows: most of [M]-OMS materials > commercial MnO2; [M]-OMS-2 > [M]-OMS-1; and among [M]-OMS-2 samples, [Ni]-OMS-2 > [Cu]-OMS-2 > [Fe]-OMS-2 > [Co]-OMS-2 > [Mg]-OMS-2. The kinetics and a mechanism of H2O2catalytic decomposition over [M]-OMS materials were studied and proposed, as well.