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Declines in gas exchange of mature leaves of Populustremuloides Michx. (quaking aspen) seedlings under four O3 treatments were investigated in a 33-d study. Gas exchange fell gradually with time, but under O3 exposure declines were accelerated. Photosynthetic capacity, stomatal conductance, and carboxylation efficiency were highly correlated, suggesting a coordinated reduction in the physiological activity of stressed leaves. Intercellular CO2 was not significantly different among treatments, indicating that stomatal opening was not the primary factor in limiting photosynthesis. Analysis of A:Ci response curves revealed that stomatal limitation increased only slightly, while biochemical limitation more than doubled, reaching a maximum of 47.1% by the third week of fumigations. Number of surviving leaves, ratio of surviving leaves to leaves produced, and total leaf area declined with O3 exposure. Whole-plant response curves were less linear than curves for the oldest subset of leaves because new leaves were produced continuously during the study, resulting in within-plant variation in O3 exposure. Declines in photosynthesis were greater than leaf area losses when data were expressed as a percentage of the control treatment. These results indicate that exposure to O3 for a relatively short time severely limits plant carbon gain in a sensitive free-growing species like aspen.

Glutathione (GSH) status has been shown to play a major role in the protection of developing rodent embryos from chemical insult during the teratogen-sensitive period of early organogenesis. Intracellular GSH concentrations in the embryo proper and visceral yolk sac are significant and appear to be regulated spatially and temporally during normal development and in response to chemical exposure. Selective modulation of GSH status in the conceptus in vitro has provided important information regarding the synthesis, utilization and turnover of GSH, as well as its role in protecting the developing embryo from electrophiles, free radicals and oxidative damage. Studies with the embryotoxic metabolite of 2-acetylaminofluorene, 2-nitrosofluorene (NOF), have shown that, although NOF forms adducts with GSH and that proper GSH status is critical for embryo protection, the most likely mechanism of protection is not through adduct formation. The GSH-dependent metabolism of NOF to aminofluorene, a less toxic product, appears to be responsible for the reduction of embryotoxicity when GSH synthesis is stimulated with a cysteine pro-drug. Additional studies have shown that the glutathione disulfide (GSSG) formed in the course of bioactivation, peroxidative metabolism and as a result of oxidative stress may be a common mediator in a number of embryotoxicities. Evaluation of the direct oxidation of GSH through exposure to the thiol oxidant diamide has shown that the teratogenicity or embryotoxicity of diverse chemicals could be mediated through the direct alteration of GSH status, leading to disruption of normal cellular homoeostasis and to alterations in important biochemical pathways as a result of the S-thiolation of critical protein sulfhydryls.

Two-year-old ponderosa pine seedlings (Pinus ponderosa Laws.) were exposed to episodic O(3) concentrations in open-top chambers for two consecutive growing seasons (June through September of 1990 and 1991). Near the end of the second season of O(3) exposure, gas exchange was measured on needles of surviving flushes at saturating CO(2) and photosynthetic photon flux density (PPFD). Both photosynthetic capacity (A(sat)) and stomatal conductance to water vapor (g(wv)) declined linearly with needle age but differences within a flush were also found. Gas exchange rates of needles from the base of the current-year flush were significantly lower than those of needles from the top of the flush, even though age differences between needles were negligible. Although most measurements were conducted at saturating CO(2), similar patterns of gas exchange were also found at 350 micro mol mol(-1) CO(2), indicating that photosynthesis of needles at the bottom of the flush was more strongly affected by O(3) than that of needles at the top of the flush, even though the potential for O(3) uptake was probably less in needles at the bottom of the flush because of reduced stomatal conductance. Carboxylation efficiency (deltaA/deltaC(i)), the linear slope of the A/C(i) response, was highly correlated with A(sat), varying with needle age, needle position in the flush and O(3) exposure, but the magnitude of the reductions was greater than for A(sat). We conclude that susceptibility to O(3) damage among needles of an individual seedling varies not only with needle age but also with needle position, and that reductions in photosynthetic capacity may not be directly attributable to increased uptake of the pollutant. The data also indicate the need to consider within-flush variation when estimating whole-plant carbon gain and O(3) uptake.

We report Raman scattering from wurtzite single-crystalline InGaAs nanowires (NWs) to probe optical phonon behaviors associated with spatial grading in alloy composition along the NW length. Polarized Raman spectra revealed several optical phonons and their scattering symmetries: (i) InAs-like A 1(LO) and A 1(TO) phonons and (ii) GaAs-like A 1(LO), A 1(TO), and E 2(high) phonons. In addition, strong anisotropic behavior was observed in the Raman tensor elements of the A 1(TO) phonon mode. Interestingly, a spatial mapping of the GaAs-like A 1(TO) phonon along the NW length direction showed a systematic increase in energy from the NW top (~255 cm−1) to the midpoint (~263 cm−1), indicating an increase in the Ga mole fraction from about 0.5 to about 0.8. Further toward the NW bottom, the GaAs-like A 1(TO) phonon energy saturated to the peak value at about 264 cm−1. In the upper half of the NW, the phonon linewidths broadened significantly due to the spatial grading in In/Ga composition along the NW length. When the composition grading was negligible in the bottom half of the NW, the spectral widths were considerably narrowed. The GaAs-like E 2(high) phonon showed similar variations in both energy and spectral width along the NW length.

Polypropylene was implanted with 100 keV titanium and silver ions to fluences of 1, 10 and 50×1019 ions m−2 using a vacuum arc metal-ion source. The implanted specimens were tested for sliding reciprocating wear properties using a nylon counterface, 1 N normal load, 3 mm stroke length and 10000 sliding cycles. The results of the wear tests showed that there was a dramatic improvement in wear properties for the 50×1019 ions m−2 titanium-implanted specimen, to the point that no wear damage was visibly evident after 10000 cycles. A similar wear improvement was not obtained for the lower fluences for titanium implantation or for the silver-implanted specimens. The improvement in wear properties was related to the mechanisms of linear energy transfer from the incident ions to the polypropylene substrate, and consequent effects on cross-linking, which is responsible for changes in properties. The linear energy transfer was quantified using Monte Carlo calculations. In addition, friction coefficient values were also correlated with the wear test results. The significance of high fluences for wear improvements by ion implantation was demonstrated in this study. The investigation showed that metal-ion implantation can be effective in significantly improving wear properties of polymers with a judicious choice of ion type and ion fluence.

Bladder exstrophy is a very rare congenital malformation in which the anterior wall of the bladder is absent, and the posterior wall is exposed externally. Although sonographic findings of bladder exstrophy have been documented, we report a case presenting with a solid mass in the lower fetal abdomen with umbilical arteries running alongside the mass. The relationship between umbilical arteries and bladder exstrophy is a new sonographic finding which may be helpful in the prenatal diagnosis of this condition.

Chronic urticaria (CU) is a common skin disorder that affects the well-being and quality of life (QOL) of patients. Recently, we developed and validated a questionnaire for measuring QOL in Korean patients with CU, called the Chronic Urticaria-Specific Quality of Life (CU-QOL) questionnaire.To evaluate the clinical significance of a computerized version of the CU-QOL, in adult patients with CU.This was a cross-sectional observational study that enrolled 249 Korean patients with CU from five university hospitals and measured computerized CU-QOL scores and Urticaria Activity Score (UAS) simultaneously. The internal consistency of the computerized CU-QOL was analysed using Cronbach α. To identify clinical correlations between the CU-QOL and patient characteristics, the atopic status and serum autoantibodies, including antinuclear, antithyroglobulin and antimicrosome antibodies, were measured. Multiple linear regression models were used to identify CU-QOL predictors.Cronbach α was 0.94 for the overall computerized CU-QOL score. The CU-QOL scores correlated significantly with the UAS (r= -0.49, P0.001). Of the factors aggravating CU, delayed pressure, sunlight exposure and emotional stress significantly influenced the overall CU-QOL scores in the univariate analysis. Multivariate regression models indicated that UAS and emotional stress were significant predictors of the four domains and of the total CU-QOL scores.The computerized CU-QOL is a convenient and valid tool for measuring QOL in patients with CU. This study suggests that UAS, dermatographism and emotional stress are strong CU-QOL predictors in Korean patients with CU.

InSb nanostructures embedded in InAs and InAsSb matrices were grown on InAs (001) and GaAs (001) substrates by molecular beam epitaxy. The diameter and height of InSb quantum dots (QDs) on InAs with 2ML-InSb coverage grown by Stranski-Krastanov (S-K) are ~36.8 nm and ~3.1 nm, respectively. The density of QDs is ~2.5×1010 cm-2. The size distribution of InSb QDs on InAs with 2ML-InSb coverage grown by migration enhanced epitaxy (MEE) was larger than that of its S-K counterpart. Unique InSb quantum dashes (Q-dashes) on InAsSb elongated along two directions were found on an AlSb-buffered GaAs substrate. InSb Q-dashes grown by migration enhanced epitaxy (MEE) were ~159 nm in length, ~63 nm in width, and ~11 nm in height. A large reduction of volume of InSb structures between those in the matrix and those on the surface was found. Threading disl°Cations resulting from the Q-dash structures were also observed. This may be attributed to As-Sb exchange.

We fabricated GaAs/AlGaAs quantum dots by droplet epitaxy method, and obtained the geometries of the dots from scanning transmission electron microscopy data. Post-thermal annealing is essential for the optical activation of quantum dots grown by droplet epitaxy. We investigated the emission energy shifts of the dots and underlying superlattice by post-thermal annealing with photoluminescence and cathodoluminescence measurements, and specified the emissions from the dots by selectively etching the structure down to a lower layer of quantum dots. We studied the influences of the degree of annealing on the optical properties of the dots from the peak shifts of the superlattice, which has the same composition as the dots, since the superlattice has uniform and well-defined geometry. Theoretical analysis provided the diffusion length dependence of the peak shifts of the emission spectra.

Eight complex austenitic stainless steel alloys based on the composition Fe-13Cr-15Ni-2Mo-2Mn-0.2Ti-0.8Si-0.06C were implanted simultaneously with 400-keV B+ and 550-keV N+ ions and were investigated for changes in fatigue properties and surface microhardness. The nearsurface hardness of all eight alloys improved, but the fatigue life of each decreased. These findings were contrary to those obtained in an earlier study using four simple Fe-13Cr-15Ni alloys, where the dual implantation improved fatigue life by up to 250 pct. While unimplanted specimens failed by slip-band crack initiation, it was hypothesized that the dual implantation suppressed slip to the extent that fewer slip-band cracks were initiated and these were subjected to accelerated crack propagation. In addition, grain-boundary cracking was promoted, yielding a lower fatigue life. Support for this hypothesis was obtained by a study of single crystals of Fe-15Cr-15Ni, which were also implanted with B+ and N+. The dual implantation caused a lower fatigue life due to concentration of slip along a few slip bands to relieve applied stress. Evidence of grain-boundary cracking was obtained using the four simple alloys, which were subjected to triple ion implantation with B+, N+, and C+. The triple implantation decreased the fatigue life of the alloys and caused accelerated growth of fewer slip bands and grain-boundary cracking due to suppression of surface slip bands. This study thus shows the existence of an optimum level of strengthening when multiple ion implantation is used to improve the fatigue properties of alloys.

We have fabricated step-edge junctions (SEJs) using YBCO films deposited on MgO substrates. The substrate step-edge produced at desired places were prepared by a chemical solution as one of simple fabrication techniques for Josephson junctions. The microstructures of the YBCO films were observed by HRTEM, which clearly showed a 40° tilted grain boundary at the concave side of the step. The I–V characteristics, millimeter-wave response of the SEJs were investigated. The response of millimeter-wave radiation ( ƒ = 94 GHz ) to the SEJs exhibited Shapiro steps of 194 μV interval. The traditional behavior in terms of the voltage versus magnetic flux curves was clearly observed in the d.c.-SQUIDs fabricated with the SEJs.

Recently, the clonal integration of a new human polyomavirus (Merkel cell polyomavirus or MCPyV) has been reported in Merkel cell carcinoma (MCC). In order to investigate the presence of MCPyV in small cell carcinomas (SCCs) and small round cell tumors (SRCTs), we collected formalin-fixed paraffin-embedded tissue specimens including 14 MCCs, 24 SCCs, 7 Ewing sarcoma/primitive neuroectodermal tumors (ES/PNETs) and 5 neuroblastomas. We also collected specimens of other cancers including 12 malignant melanomas, 10 breast, 10 ovarian and 20 gastric cancers. We used 3 primer sets for which the sequences were previously published (LT1, LT3, and VP1) and 3 newly designed primer sets (LT1-1, LT1-1a, and LT3a). Quantitative real-time PCR was also performed with the LTq primer set. Nested PCR using the LT3a primer set detected more cases of MCPyV infection in MCC. In total, 12 of 14 (85.7%) MCC cases were positive for MCPyV by PCR, which was consistent with published data. Some SCC specimens were also positive for MCPyV (37.5%) by PCR. PCR products from MCC and SCC cases showed premature truncation and frameshift mutation. Furthermore, one case of ES/PNET and one gastric carcinoma showed MCPyV DNA. However, MCPyV DNA and transcript were only detected in MCCs with quantitative real-time PCR analysis. In addition, 11 of 13 (84.6%) MCC cases and 6 of 23 (26.1%) SCC cases showed immunoreactivity with monoclonal antibodies against MCPyV large T-antigen. Considering both PCR and IHC results, MCPyV was detected in all MCCs tested. The presence of MCPyV in all MCC cases tested and in some SCC cases suggests that MCPyV may be involved in the malignant transformation.

SETTING: Nucleic acid amplification tests can detect Mycobacterium tuberculosis complex rapidly and reliably. OBJECTIVE: To compare the diagnostic performance of the artus ® M. tuberculosis PCR Kit and COBAS ® AMPLICOR™ Mycobacterium tuberculosis Test. In the artus assay, an appropriate cycle threshold (Ct) value was determined for positivity. DESIGN: A total of 238 clinical respiratory specimens were analysed using both the artus and COBAS AMPLICOR assays. In 221 specimens, these results were further compared with culture results. RESULTS: The overall agreement between artus and COBAS AMPLICOR was 96.2% (229/238). Among the nine (3.8%) discrepant specimens, three (1.3%) were artus-positive and COBAS AMPLICOR-negative, while the other six (2.5%) were artus-negative and COBAS AMPLICOR-positive. Using culture as a standard, the sensitivity and specificity of the artus assay were 97.8% and 85.1%, and those of COBAS AMPLICOR assay were 100% and 86.2%, respectively. The difference was not statistically significant. In the artus assay, the minimum Ct value for the positivity determination was 38. CONCLUSION: The artus and COBAS AMPLICOR assays showed comparable diagnostic performance and can be confidently used for detection of M. tuberculosis complex. In the artus assay, a Ct value of 38 could be suggested as an appropriate cut-off value.

Increasingly, genetically modified crops are being developed to express multiple 'stacked' traits for different types of transgenes, for example, herbicide resistance, insect resistance, crop quality and tolerance to environmental stresses. The release of crops that express multiple traits could result in ecological changes in weedy environments if feral crop plants or hybrids formed with compatible weeds results in more competitive plants outside of agriculture. To examine the effects of combining transgenes, we developed a stacked line of canola (Brassica napus L.) from a segregating F(2) population that expresses both transgenic glyphosate resistance (CP4 EPSPS) and lepidopteran insect resistance (Cry1Ac). Fitness-associated traits were evaluated between this stacked genotype and five other Brassica genotypes in constructed mesocosm plant communities exposed to insect herbivores (Plutella xylostella L.) or glyphosate-drift. Vegetative biomass, seed production and relative fecundity were all reduced in stacked trait plants when compared with non-transgenic plants in control treatments, indicating potential costs of expressing multiple transgenes without selection pressure. Although costs of the transgenes were offset by selective treatment, the stacked genotype continued to produce fewer seeds than either single transgenic line. However, the increase in fitness of the stacked genotype under selective pressure contributed to an increased number of seeds within the mesocosm community carrying unselected, hitchhiking transgenes. These results demonstrate that the stacking of these transgenes in canola results in fitness costs and benefits that are dependent on the type and strength of selection pressure, and could also contribute to changes in plant communities through hitchhiking of unselected traits.

Postpartum ultrasound investigation of a woman with unremitting fever and right flank pain after Cesarean section revealed an extensive thrombosis of the right ovarian vein which extended into the inferior vena cava. Computed tomography was required to substantiate the diagnosis. Medical treatment with intravenous urokinase and heparin and antibiotics was successfully performed. During the postpartum period, the possibility of ovarian vein thrombosis should be considered in febrile patients with abdominal pain who are not responding to antibiotics, and imaging studies such as ultrasound and computed tomography should be performed early for prompt diagnosis and therapy.

The aim of this study was to evaluate the efficacy of ondansetron and ramosetron in the reduction of post-operative nausea and vomiting (PONV) associated with patient-controlled analgesia (PCA) after cardiac surgery.A total of 320 patients scheduled for elective cardiac surgery were enrolled. Patients were randomly assigned to one of four treatment regimens (n=80 in each group): no prophylactic antiemetics (group P); intravenous (i.v.) ondansetron 4 mg at the end of surgery and 12 mg added to PCA (group O); i.v. ramosetron 0.3 mg at the end of surgery and no antiemetics added to PCA (group R1); and i.v. ramosetron 0.3 mg at the end of surgery and 0.6 mg added to PCA (group R2).The incidence of PONV during the 48-h post-operative period was lower in groups O (46%), R1 (54%), and R2 (35%) compared with group P (71%, P0.001). The incidence and severity of nausea were lower in groups O, R1, and R2 than in group P during the 24-h post-operative period, whereas the incidence and severity of nausea during 24-48 h after surgery were lower in groups O and R2, but not in group R1, than in group P. Compared with group P (53%), the frequency of rescue antiemetic usage was significantly lower in groups O (34%) and R2 (29%), but not in group R1 (43%).The addition of either ondansetron or ramosetron to PCA can reduce the incidence of PONV during 48 h after cardiac surgery.

Rhodococcus sp. EH831 is a microbial species that can degrade volatile organic compounds. We optimized a method for monitoring quantitative real-time PCR (qRT-PCR) of EH831 that was incorporated into a polyurethane (PU) biofilter. When the genomic DNA of EH831 was directly extracted from a PU sample with immobilized EH831, the recovery efficiency was very low due to DNA absorption into the PU. DNA amplification during PCR was also inhibited by PU impurities. Therefore, a pre-treatment step was necessary. We successfully recovered cells from the PU by squeezing the matrix, adding sterilized water, and vortexing. The recovery efficiency ranged from 105 to 144%, and there was no statistically significant difference. We designed a novel TaqMan probe for EH831 and demonstrated its high specificity for EH831. The detection range for EH831 was 10(5)-10(11) CFU ml(-1). The method described in this study can be used to investigate the relationship between quantitative analysis of Rhodococcus sp. EH831 and PU biofilter performance.

Austenitic Fe-Cr-Ni steels are potential candidate alloys for structural materials in both fast breeder and magnetic fusion reactors. However, void swelling and phase instability during irradiation have been major problems limiting the properties and useful lifetimes of these materials and thus have been the subject of intensive investigations. Cavity nucleation in steels subjected to displacement damage is strongly influenced by the interactions between helium atoms and precipitates which are formed during irradiation. Several important mechanisms regarding gas atom-precipitate interactions and principles for the design of radiation-resistant alloys are critically examined. Central concepts derived from theory, including the critical radius and critical number of gas atoms, cavity-precipitate interactions, and relative sink strengths for point defects, are applied to the interpretation of experimental data.

The tuning properties of epitaxial Ba0.5Sr0.5TiO3 (BST) thin films were investigated by a scanning microwave microscope (SMM) and an LCR meter. Although the BST films on LaAlO3 and MgO substrates showed similar tuning behavior when measured by the LCR meter at 1 MHz, remarkably different tuning properties were observed in the planar capacitors measured by SMM. The BST films on LaAlO3 substrates were hardly tuned when measured by SMM, while the BST films on MgO showed significant tuning behavior between the electrodes. We attribute these different tuning properties to the anisotropic tuning caused by the strain in BST films. This will enable the design of much improved tunable devices while minimizing the loss associated with the dielectric.

Bispectral index (BIS) values derived from the left and right forehead are usually the same. We report on two patients with unilateral carotid artery stenosis in whom we observed differences between the BIS values obtained from sensors placed on each side of the forehead. During surgery, the BIS values of the diseased side decreased more than those of the opposite side when the mean arterial pressure decreased below 70 mmHg. BIS monitors should be used with caution in patients with unilateral carotid artery and cerebrovascular disease.

Mechanisms by which oxygen affects swelling during Fe-ion irradiation are investigated in a series of Fe-15Ni-13Cr-base alloys containing minor additions of titanium, silicon and carbon. The irradiations are carried out at 948 and 1000 K to doses up to 100 dpa. Effects of both residual oxygen content and accelerator-injected oxygen are studied. It is found that pre-injected oxygen promotes cavity swelling and, in some cases, leads to a fine distribution of stable bubbles for oxygen injection levels as high as 1000 at.p.p.m. The results are interpreted in terms of the chemical activity of oxygen in forming precipitates with alloying elements, and in terms of radiation dissolution of oxygen leading to oxygen-pressurized bubbles. Accounting for the interaction with alloying elements, we conclude that oxygen exhibits a direct cavity-pressurization effect on swelling similar to that previously reported for helium. The results are analyzed in terms of the theory of the critical radius and critical numb...

Central concepts in the theory of swelling based on defect reactions are reviewed. The critical radius and critical number of gas atoms, which determine the initiation of swelling, and the ratio of the dislocation and cavity sink strengths, which dictates the swelling rate, are demonstrated to be of great utility in the understanding and control of swelling. Over the past two decades, a large data base has been accumulated covering austenitic and ferritic/martensitic alloys, the leading candidate materials for both fusion and fast fission reactor applications. This collection of data naturally serves as the largest source of information on which to develop and test mechanistic understanding of swelling. Over wide ranges in materials and irradiation parameters, including composition, temperature, damage rate, and helium generation rate, we find that apparently divergent swelling behaviors can be explained in a unified manner within the present theoretical framework. Principles for microstructures that insure swelling resistance, together with results from the necessary confirmatory experiments, are described.

The extensive literature on oxygen chemisorption and solubility in metals is briefly reviewed, with special emphasis on the reduction of surface tension associated with oxygen adsorption. A thermodynamic model based on the adsorption equations of Gibbs and Langmuir is developed to determine the relative stability in the presence of oxygen of the void compared to the dislocation loop and stacking fault tetrahedron. Representative calculations are performed for copper, nickel, and austenitic stainless steel. Atomistic and elastic continuum calculations predict that void formation should not occur in most pure face-centered cubic metals during quenching or irradiation. However, the thermodynamic model predicts that oxygen concentrations of 30 to 1000 appm will stabilize void formation in copper, nickel, and stainless steel. Foils of copper and several Fe-Cr-Ni stainless steels containing various amounts of oxygen have been examined with electron microscopy following ion bombardment. The presence of 30 to 1000 appm O resulted in significant amounts of void formation, whereas no voids were observed in low-oxygen specimens, in agreement with the model predictions. Oxygen introduced by ion implantation was more effective in promoting void formation than residual oxygen. Solutes such as phosphorus in stainless steel reduced the effectiveness of oxygen as a void-stabilizing agent.

Three cold-worked phosphorous-modified Fe-15Ni-13Cr-base alloys were irradiated with simultaneous Fe- and He-ion beams to doses of about lOOdpa at a helium implantation rate of 20at.p.p.m./dpa. The three alloys correspond to compositions that led to increasing densities of a very fine phosphide precipitate. In the case of the alloy with the highest precipitate density, the swelling was suppressed to the greatest extent. The results are interpreted in terms of the theory of cavity swelling, which provides the central concept of a critical radius and critical number of gas atoms required for cavity swelling. The large interfacial area of the needle-shaped phosphide precipitates led to profuse bubble nucleation at the interface. The high density of bubbles slowed the accumulation of gas atoms in individual bubbles and thus delayed the onset of point-defect-driven cavity swelling. After interpreting the present data in terms of these concepts, more general features of cavity swelling reduction by an ...

Previously proposed shape of the optical via structures are simple 45 degree mirrors with or without metal coatings, and simple elliptical shapes. To improve alignment tolerance and coupling efficiency, various shape of the optical via structures are fabricated and optical characteristics of the shapes are measured.

Band-gap lowering due only to the cation ordering effect is investigated in InAlAs layers grown on InP by using photoluminescence measurement. Double-crystal x-ray diffraction and Rutherford backscattering measurements confirm that both of the InAlAs epilayers studied, grown at 700 and 750 °C, are lattice matched with InP substrates. Through transmission electron diffraction measurements, it is observed that a CuPt-type ordering structure is formed in the InAlAs layers grown at 700 °C but not in the layers at 750 °C. Photoluminescence measurements at 1.7 K reveal that the band-gap energy of the ordered InAlAs is smaller by 60 meV than that of the unordered InAlAs.

This workshop comprised thirteen participants from nine countries, of whom eight had developed and/or undertaken surveys supported by non-web technologies. There is a long list of technologies but this paper will focus mostly on survey applications of ‘LADs’—Location/time Aware Devices—such as Global Positioning Systems (GPS) and mobile telephone technologies. In addition, this paper covered, to some extent, technologies that are used to support or supplement LADs, such as dead reckoning systems, accelerometers, and electronic systems for vehicle identification and toll collection. The paper would have liked to include computing developments, especially mobile computing, more broadly in the discussion, but within the time available it was necessary to limit the paper to those that can be linked to LAD data, such as electronic schedulers on Personal Digital Assistants (PDAs) or virtual reality displays. Computer-Aided-Self-Administered Interviews (CASI) are close in concept to Web-based methods but not included in this paper. However, this paper does include the use of the Web and Internet for data transmission for obtaining feedback from participants in LAD-supported surveys.

Heelys, a type of shoes with stealth wheels, are extremely popular among children in Singapore. The widespread availability of cheap imitations has led to a proliferation of young users. Coupled with a total lack of safety equipment and instructions, these shoes can lead to significant injuries. The purpose of this study was to examine the incidence and type of injuries sustained by children using Heelys.During a seven-month period from February to August 2004, all children treated at the Paediatric Orthopaedic Department of the KK Women's and Children's Hospital, were asked if the injury was sustained while "heeling". All the patients were reviewed by the authors. A total of 37 patients with significant injuries sustained while "heeling" were identified. Their radiographs and clinical charts were reviewed. The patients and/or their parents were also interviewed to obtain additional information.Upper limb injuries were by far the most common. Distal radius fractures and elbow injuries predominated. None of the children used safety gear."Heeling" can lead to serious injuries despite the relatively low velocity involved. Children and their parents need to be educated on the use of safety gear.

A high temperature superconducting YBa2Cu3Oy array of five Josephson junctions designed with additional coupling lines has been developed to demonstrate the effects of frequency locking and impedance matching for applications such as oscillators, mixers, and detectors. The Josephson self-radiation power was directly detected by a superheterodyne receiver, and Shapiro steps were also measured. The Josephson self-radiation properties reveal good quality of phase locking and microwave coupling with external circuits. The maximum self-radiation power of our array is about 50 pW which is several ten times higher than that of a single Josephson junction, and its peak point exactly satisfies the Josephson current-voltage relation. The Shapiro-step measurements show that the behavior of current-voltage curve depends on the effective inductance of coupling lines which affects the total impedance of Josephson junction array and microwave coupling. The Josephson oscillation frequency was obtained up to about 880 GHz...

The current study confirmed earlier conclusions regarding differential ozone (O(3)) tolerances of two soybean cultivars, Essex and Forrest, and evaluated antioxidant enzyme activities of these two varieties based on their performance under environmentally relevant, elevated O(3) conditions. The experiment was conducted in open-top chambers in the field during the 1994 and 1995 growing seasons. Exposure of plants to moderately high O(3) levels (62.9 nl l(-1) air, 2-year seasonal average) caused chlorophyll loss and increased membrane permeability when compared to control plants grown in charcoal filtered air (24.2 nl l(-1) air). The other effects of O(3) treatment were decrease in seed yield, loss of total sulfhydryl groups, reduction of soluble protein content, and increase in guaiacol peroxidase activity in leaves of both cultivars. The O(3)-induced increase in guaiacol peroxidase activity was much smaller in cv. Essex leaflets. Cv. Essex had less leaf oxidative damage and smaller reduction in seed yield than cv. Forrest under elevated O(3) conditions. During ozonation, mature leaflets of the more O(3) tolerant cv. Essex had higher levels of glutathione reductase (30%), ascorbate peroxidase (13%), and superoxide dismutase (45%) activity than did mature leaflets of cv. Forrest. Cu,Zn-superoxide dismutase, which represented 95% of total superoxide dismutase activity in the two cultivars, appeared to be increased by O(3) exposure in the leaflets of O(3) tolerant cv. Essex but not in those of cv. Forrest. Cytosolic ascorbate peroxidase activity was also higher in leaflets of cv. Essex than in cv. Forrest regardless of O(3) level. Stromal ascorbate peroxidase and Mn-superoxide dismutase activity did not appear to be involved in the O(3) tolerance of the two soybean cultivars.

The Department of Orthopaedic Surgery at the University of Malaya (in Singapore) was established in 1952. Prior to this, the teaching of Orthopaedic Surgery at the University was undertaken by the Department of Surgery under the Professor of Surgery and Professor of Clinical Surgery. From a course consisting of 15 weekly classes on fractures for 18 undergraduates in the late 1930s, and the clinical postings in orthopaedic surgery for over 40 students in 1952, the programme now encompasses an exposure to musculoskeletal diseases and trauma in all 5 years of the undergraduate course. Over this time, the spectrum of clinical conditions has also changed, and with it the emphasis on the conditions to be taught; from that dealing primarily with tuberculosis of bones and joints, poliomyelitis, and childhood deformity, to those resulting from degenerative disorders, sports injuries, industrial and motor vehicle accidents, and cancer. The students are now taught orthopaedic surgery in all the major public hospitals. Local postgraduate training programmes for orthopaedic surgery started in the 1980s. From 1993, a more structured training and assessment programme was introduced for basic and advanced training in surgery and orthopaedics. Advanced trainees rotate through the various teaching hospitals to expose them to a wider range of orthopaedic problems as well as teachers. The postgraduate training programme is now well established, and Singapore is accredited by the Royal College of Surgeons of Edinburgh as an orthopaedic training centre for higher surgical training.

An infant was admitted for evaluation of respiratory distress and tracheomalacia. After several weeks of hospitalization, both the infant and her mother were diagnosed with culture-positive pulmonary tuberculosis (TB). Sixteen pediatric patients and 293 health care workers were evaluated for exposure to Mycobacterium tuberculosis. Tuberculin skin test conversions occurred in 6.7% of patients and 1.9% of pediatric health care workers. While nosocomial transmission of TB is relatively rare in children's hospitals, this report highlights the differences between TB control efforts in pediatric vs. adult facilities, including the importance of screening the adult visitors of children admitted with suspected TB.

A key factor in the tissue engineering approach to tissue repair and regeneration is the use of appropriate cells. Mesenchymal stem cells (MSCs) are derived from bone marrow stroma or connective tissues and they have the potential to differentiate into various mesenchymal cell lines in vitro and in vivo. These cells hold great promise for musculoskeletal tissue engineering. This review is based mainly on the work which has been done in the National University of Singapore on the use of MSCs for engineering cartilage, growth plate, bone and tendon/ligament as well as the clinical trail of autologous chondrocyte implantation. It can help to shape future research on musculoskeletal tissue engineering.

Three Korean girls with ethylmalonic encephalopathy, the first Asian cases, were identified. In all three cases, we observed slight improvement in motor functions, cognitive behaviours and chronic mucoid diarrhoea after treatment with riboflavin and/or coenzyme Q10 treatment. The precise pathogenesis of ethylmalonic encephalopathy has not been fully elucidated, but riboflavin treatment may be helpful.

Postpartum ultrasound investigation of a woman with unremitting fever and right flank pain after Cesarean section revealed an extensive thrombosis of the right ovarian vein which extended into the inferior vena cava. Computed tomography was required to substantiate the diagnosis. Medical treatment with intravenous urokinase and heparin and antibiotics was successfully performed. During the postpartum period, the possibility of ovarian vein thrombosis should be considered in febrile patients with abdominal pain who are not responding to antibiotics, and imaging studies such as ultrasound and computed tomography should be performed early for prompt diagnosis and therapy.

Microscopic structures of light emitting porous silicon layers have been studied. The samples prepared in an aqueous HF solution by anodizing p‐type silicon substrates show a strong positional dependence of photoluminescence and Raman spectra. The photoluminescence peaks are broad around 1.8 eV, where the photoluminescence intensities are comparable to that of GaAs at 5 K. We have found from Raman studies showing two characteristic peaks at 500 and 520 cm−1 that microscopic structures reveal gradual changes from porous silicon to a mixture of polycrystalline and hydrogenated amorphous phases as the probing spot is moved to the edge of the sample. This is explained by the redeposition of silicon atoms on top of the porous silicon layers near the edge of the sample as a result of liquid flow caused by bubbles of hydrogen gas which was produced near the surface of the sample during the anodization process.

After three years of upgrading work, PLS-II (S. Shin, Commissioning of the PLS-II, JINST, January 2013) is now successfully operating. The top-up operation of the 3 GeV linear accelerator had to be delayed because of some challenges encountered, and PLS-II was run in decay mode at the beginning in March 2012. The main difficulties encountered in the top-up operation of PLS-II are different levels between the linear accelerator and the storage ring, the 14 narrow gap in-vacuum undulators in operation, and the full energy injection by 3 GeV linear accelerator. Large vertical emittance and energy jitter of the linac were the major obstacles that called for careful control of injected beam to reduce beam loss in the storage ring during injection. The following measures were taken to resolve these problems: (1) The high resolution Libera BPM (see http://www.i-tech.si) was implemented to measure the beam trajectory and energy. (2) Three slit systems were installed to filter the beam edge. (3) De-Qing circuit was applied to the modulator system to improve the energy stability of injected beam. As a result, the radiation by beam loss during injection is reduced drastically, and the top-up mode has been successfully operating since 19th March 2013. In this paper, we describe the experimental results of the PLS-II top-up operation and the improvement plan.

Electrical injuries resulting in physeal injury in children are an uncommon but well-recognized clinical entity. Almost all these injuries are sustained from man-made electrical sources. To date, there have been no published cases of growth arrest after lightning strike. The authors report the case of a 12-year-old girl who survived a lightning strike 2 years ago and who presented with asymmetric growth arrest in both legs. The authors discuss the pathophysiology of lightning strike and consider the evidence for direct electrical injury versus ischemic insult to the physis as explanations for the cause of the growth arrest observed in this patient.