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New Zealand lower thrips (NZFT, Thrips obscuratus (Crawford)) were exposed to a range of ethyl formate (EF) and pyrethrum-based postharvest treatments on apricots. Research showed that EF+CO 2 or EF+N 2 were effective treatments against NZFT and caused negligible damage to apricot fruit quality. However, pyrethrum dipping did not effectively control NZFT and caused signiicant internal damage to apricot fruit. Lethal concentration (LC 99 ) estimates were developed for adult and larval NZFT using a range of EF concentrations (0-1.27% EF+CO 2 ) and temperatures (5, 15 and 25°C). It is estimated that treatments of 1% (30.7 g/m 3 ) EF at 5 or 25°C or a higher concentration of 1.5% (46.3 g/m 3 ) at 15°C will achieve 99% mortality of NZFT adults and larvae on apricot fruit with 95% conidence.

A shipboard piping system can be considered analogous to the transport and distribution system of a land-based piping system. The intakes and supply pumps provide the initial uptake and head pressure while the piping system provides the distribution throughout the rest of the ship. Piping systems must not degrade or corrode due to the contained fluid but also must endure structural loadings. Interior damage can come in the form of corrosion such as pitting, general wasting away of material due to galvanic corrosion, mechanical deformations due to structural and vibrational loadings. A decision matrix based framework for evaluation using a modified Pugh Controlled Convergence technique was developed for evaluation of metallic coatings under consideration for shipboard system repairs which included mechanical and electrochemical performance characteristics. Candidate coatings for further study and additional testing requirements are identified through the process. The mechanical evaluation focuses on microstructural characterization and mechanical response. The electrochemical evaluation focuses on general corrosion and galvanic interactions between each coating and Cu0.7Ni0.3, a common piping material also often referred to as 70-30 CuNi. The outcome of the evaluation sequence is the ranking of relative merit of coatings. Results are presented which show the wide range of characteristics possible. The extension of the decision matrix to manufacturability issues will also be discussed.

To assess the consequences of switching aspirin dosage from 100 mg/d to 40 mg/d on cardiovascular benefit, bleeding risk and platelet aggregation in very elderly patients.Arachidonic acid induced platelet aggregation(AA-Ag) was measured in 537 patients aged 80 or older treated with aspirin (100 mg/d). In the study, 100 patients with low on-treatment platelet aggregation and at high risk of bleeding and low risk of cardiovascular events, were switched to aspirin (40 mg/d) and their platelet aggregation was measured again 7 days later.Their bleeding and upper gastrointestinal symptoms were also recorded in following 3 months.The study observed a heterogeneous distributed aspirin 100 mg/d AA-Ag (range: 0.42% to 28.78%)in the 537 very elderly patients.Aspirin 100 mg/d AA-Ag before the switch in aspirin 40 mg/d group was 5.00%±2.32% and the rate of the patients with low on-treatment platelet aggregation was 71.00%. The rates of melena or occult blood positive, other minimal bleeding,upper gastrointestinal symptoms and a history of gastrointestinal bleeding in 40 mg/d group were higher than those in 100 mg/d group. On a regimen of aspirin 40 mg/d, AA-Ag increased to 11.21%±4.95%(range: 2.12% to 28.84%) with 95.00%of the patients with AA-Ag20% and the rate of the patients with low on-treatment platelet aggregation was 15.00%. Multiple variable analysis revealed that aspirin 40 mg/d AA-Ag was significantly influenced by aspirin 100 mg/d AA-Ag, BMI and platelet counts. The rate of gastrointestinal bleeding decreased from 12.00% to 5.00%,and upper gastrointestinal symptoms decreased from 59.00% to 21.00% after the switch in 40 mg/d group.Switching aspirin dosage from 100 mg/d to 40 mg/d reduces the bleeding events and improves upper gastrointestinal symptoms, thus inhibiting platelet aggregation effectively in very elderly patients.

To explore the role of mitochondrial apoptosis on pulmonary fibrosis in rats with severe scald injury.According to the random digital table, a total number of 32 Wistar rats were divided into 4 groups: sham burn (group A), burn group (group B), 12-week post burn recovery group (group C), and 12-week post burn recovery plus a second burn injury group (group D). In group A and group B, lung tissues were harvested on post burn day 4. After received first burn injury 12 weeks, the group C and group D received separately a second sham burn injury and burn injury. Lung tissues were harvested on post burn day 4 after the second burn injury. All tissues were examined for cells apoptosis by Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling (TUNEL). Pulmonary fibrosis was assessed by Masson trichrome staining and Sirius red staining. The protein expression levels of cleaved Caspase-3, Bax and Bcl-2 were assessed by Western blot.Both Masson trichrome staining and Sirius red staining showed obvious pulmonary fibrosis in group C and group D. The apoptosis rates of group B, C and D were significantly higher than that in group A ((15.50±3.30)%, (7.88±3.10)%, (15.88±3.23)% vs (2.10±1.07)%, all P0.05). Compared to group A, cleaved Caspase-3 levels were significantly higher in group B, C and D ((0.59±0.11), (0.33±0.08), (0.73±0.13) vs (0.16±0.05), all P0.05). The ratio of Bax/Bcl-2 in group B, C and D also increased significantly ((2.08±0.30), (0.83±0.09), (1.54±0.12) vs (0.64±0.05), all P0.05).Severe burn injury can induce pulmonary fibrosis and mitochondrial apoptosis may play an important role in the development of pulmonary fibrosis.

Release testing of parental controlled release microspheres is an essential step in controlling quality and predicting the duration of efficacy. In the first of a two-part study, we examined the effect of various incubation media on release from leuprolide-loaded PLGA microspheres to understand the influence of external pH, plasticization, and buffer type on mechanism of accelerated release. PLGA 50/50 microspheres encapsulating ~5% w/w leuprolide were prepared by the double emulsion-solvent evaporation method with or without gelatin or by the self-healing encapsulation method. The microspheres were incubated at 37°C up to 56days in various media: pH5.5, 6.5, and 7.4 phosphate buffered-saline (PBS) containing 0.02% Tween 80; pH7.4 PBS containing 1.0% triethyl citrate (PBStc); and pH7.4 HEPES buffered-saline containing 0.02% Tween 80 (all media contained 0.02% sodium azide). The recovered release media and microspheres were examined for released drug, polymer molecular weight (Mw), water uptake, mass loss, and BODIPY (green-fluorescent dye) diffusion coefficient in PLGA. After the initial burst release, release of leuprolide from acid-capped PLGA microspheres appeared to be controlled initially by erosion and then by a second mechanism after day 21, which likely consists of a combination of peptide desorption and/or water-mediated breakage of pore connections. PBStc and acidic buffers accelerated degradation of PLGA and pore-network development and increased BODIPY diffusion coefficient, resulting in faster release. Release of leuprolide from the end-capped PLGA showed similar trends as found with acid capped PLGA but with a longer lag time before release. These data provide a baseline mechanistic signature of in vitro release of leuprolide for future comparison with corresponding in vivo performance, and in turn could lead to future development of rational in vitro-in vivo correlations.

To explore changes in the proteomics of lung tissue in early stage of burn-blast combined injury in rats.According to a random digital table, a total number of 18 Sprague Dawley (SD) rats were divided into burn-blast combined injury group (n=9) and blast injury group (n=9). Lung protein samples were collected at 6 h post injury. 2-DE was performed to separate proteins. After silver staining, the protein of differential expression were analyzed by PQ Quest and then identified by matrix-assisted laser desorption/ionization time of fight mass spectrometry (MALDI-TOF-MS). The features of the changes of proteomics of rat lung after burn-blast combined injury were studied by biological spectrometry, protein bank and reference article analysis technique. At same time, pathologic changes of the lung were monitored after injury.After removing death drain during the experiment, each group contained 8 rats and the results were analyzed statistically. Well focused and distinct 2-DE maps with good reproducibility were obtained, means of 736±47 and 782±30 protein spots were detected from the blast injury group and burn-blast combined injury group and the matching rates were 91%. From the two groups, 14 differential protein spots expressions were analyzed by MALDI-TOF-MS, of which 10 proteins were up-regulated and 4 proteins were down-regulated in burn-blast combined injury group. 12 different expression proteins were identified in the lung through 2-DE, mass spectrometry and protein date base, including heat shock 27 protein 1, heat shock 70 protein 1, carbonic anhydrase 2, cytochrome c oxidase, ATP synthase subunit alpha, Ca(2+) -transporting ATPase et al, which took part in stress reaction, metabolism, immune response and cytoskeleton.Burn-blast combined injury could induce dramatically changes of proteomics in lung tissue at early stage. The mechanism probably involves several proteins associated with oxidative stress, energy metabolism, immune response and cytoskeleton.

Here we describe development of a silicone rubber/stainless steel mesh cage implant system, much like that used to assess biocompatibility of biomaterials [1], for easy removal of injectable polymer microspheres in vivo . The sterile cage has a type 316 stainless steel mesh size (38 μm) large enough for cell penetration and free fluid flow in vivo but small enough for microsphere retention, and a silicone rubber shell for injection of the microspheres. Two model drugs, the poorly soluble steroid, triamcinolone acetonide, and the highly water-soluble luteinizing hormone-releasing hormone (LHRH) peptide superagonist, leuprolide, were encapsulated in PLGA microspheres large enough (63–90 μm) to be restrained by the cage implant in vivo . The in vitro release from both formulations was followed by ultra-performance liquid chromatography (UPLC) with and without the cage in a standard release media, PBS pH 7.4 + 0.02% Tween 80 + 0.05% sodium azide, at 37 °C. Pharmacokinetics (PK) in rats was assessed after SC injection or SC in-cage implantation of microspheres with plasma analysis by LC-MS/MS or EIA. Tr-A and leuprolide in vitro release was largely unaffected after the initial burst irrespective of the cage or test tube incubation vessel and release was much slower than observed in vivo for both drugs. Moreover, Tr-A and leuprolide pharmacokinetics with and without the cage were highly similar during the 2–3 week release duration before a significant inflammatory response was caused by the cage implant. Hence, the PK-validated cage implant provides a simple means to recover and evaluate the microsphere drug carriers in vivo during a time window of at least a few weeks in order to characterize the polymer microsphere release and erosion behavior in vivo . This approach may facilitate development of mechanism-based in vitro/in vivo correlations and enable development of more accurate and useful in vitro release tests.

We carried out a case-control study to examine the relationship between the ATP-binding cassette subfamily B member 1 (ABCB1) gene polymorphisms C1236T, G2677T, and C3435T and risk of acute leukemia in a Chinese population. Between May 2013 and April 2015, we recruited 164 acute leukemia patients and 285 healthy controls, and determined polymorphism genotypes by polymerase chain reaction-restriction fragment length polymorphism. Using unconditional logistic regression analysis, we observed that in comparison to the wild-type sequence, the TT genotype [odds ratio (OR) = 2.15, 95% confidence interval (CI) = 1.12-4.10; P = 0.01] and the T allele (OR = 1.39, 95%CI = 1.05-1.86; P = 0.02) of ABCB1 G2677T were associated with acute leukemia susceptibility. The TT genotype (OR = 2.03, 95%CI = 1.11- 3.69; P = 0.01) and the T allele (OR = 1.39, 95%CI = 1.05-1.85; P = 0.02) of the C3435T polymorphism also increased acute leukemia risk compared to the wild-type form. However, no significant relationship was established between the ABCB1 C1236T variant and this disease. Our results suggest that the ABCB1 G2677T and C3435T sequence variations may affect susceptibility to acute leukemia.

Shock tubes have been extensively used in the study of blast traumatic brain injury due to increased incidence of blast-induced neurotrauma in Iraq and Afghanistan conflicts. One of the important aspects in these studies is how to best replicate the field conditions in the laboratory which relies on reproducing blast wave profiles. Evolution of the blast wave profiles along the length of the compression-driven air shock tube is studied using experiments and numerical simulations with emphasis on the shape and magnitude of pressure time profiles. In order to measure dynamic pressures of the blast, a series of sensors are mounted on a cylindrical specimen normal to the flow direction. Our results indicate that the blast wave loading is significantly different for locations inside and outside of the shock tube. Pressure profiles inside the shock tube follow the Friedlander waveform fairly well. Upon approaching exit of the shock tube, an expansion wave released from the shock tube edges significantly degrades the pressure profiles. For tests outside the shock tube, peak pressure and total impulse reduce drastically as we move away from the exit and majority of loading is in the form of subsonic jet wind. In addition, the planarity of the blast wave degrades as blast wave evolves three dimensionally. Numerical results visually and quantitatively confirm the presence of vortices, jet wind and three-dimensional expansion of the planar blast wave near the exit. Pressure profiles at 90° orientation show flow separation. When cylinder is placed inside, this flow separation is not sustained, but when placed outside the shock tube this flow separation is sustained which causes tensile loading on the sides of the cylinder. Friedlander waves formed due to field explosives in the intermediate-to far-field ranges are replicated in a narrow test region located deep inside the shock tube.

The thermal degradation of a series of 1,1,2,2-tetraaryl-1,2-ethanediols has been examined using thermogravimetry (TG) and gas chromatography/mass spectrometry (GC/MS). These compounds are smoothly converted to the corresponding diaryl ketone and diaryl carbinol, i.e., the compounds undergo disproportionation arising from homolytic cleavage of the central carbon–carbon bond. Presumably, cleavage of the carbon–carbon bond generates a radical pair which disproportionates to provide the observed products.

Electrochemical impedance spectroscopy and potentiodynamic polarisation measurements were used to verify the effects of temperature and acetic acid (HAc) on the anodic and cathodic reactions in CO2 corrosion of 316L stainless steel in 3·5% NaCl solution. The tests were carried at 30, 60 and 90°C. The initiation concentration of HAc was varied between 0 and 3000 ppm. After the potentiodynamic polarisation measurements, the surface morphologies for every condition were detected by using scanning electron microscopy. In the present work, the fitting parameters of polarisation curves, such as the corrosion potential Ecorr, the corrosion current density Icorr and Tafel shopes (ba and bc), were mainly discussed. In addition, the equivalent circuit was used to fit each Nyquist plot in order to obtain the important parameters. In the last section, the probable pitting corrosion mechanisms of pit initiation and growth were also analysed and validated. The results indicated that temperature and the addition...

Aim: To investigate factors influencing complementary and alternative medicines (CAM) use among patients on warfarin.Method: Cross-sectional study of randomly selected patients at a hospital-based anticoagulation clinic in Malaysia. A 38-item validated data collection form was used to interview patients and investigate the reasons, perceived efficacy and adverse drug events experienced. Data were also collected on potential drug interactions and the international normalised ratio (INR).Results: Of the 138 randomly selected patients, 76 (55%)reported using CAM – 46 (61%) used biologically based practices such as herbal products, vitamins and supplements.Monthly household income (p = 0.05, rs = 0.13) and family history of CAM use (p = 0.001, rs = 0.32) were significantly associated and positively correlated with CAM use. 19 patients reported adverse events with warfarin use while none reported adverse events with CAM use. 19 and 58 patients, respectively,were identified as being at risk of potential interactions between warfarin–CAM and warfarin–conventional medicines. No significant difference in the mean INR was found between CAM and non-CAM users.Conclusion: A large number of patients attending the anticoagulation clinic reported using CAM. Socioeconomic factors such as monthly household income, education level and family history of CAM use were significantly related with CAM use. Routine medication interviews should include questions about concomitant CAM use.

Background: Breast cancer patients on aromatase inhibitors (AIs) are at an increased risk for decreased bone density and fractures. Given the important role vitamin D plays in bone metabolism, vitamin D deficiency may place these patients at an additional risk. Our objective was to examine the prevalence of and risk factors for vitamin D deficiency in post-menopausal breast cancer survivors (BCS) with current or past AI use. Materials and Methods: We conducted a cross-sectional study. Vitamin D levels were obtained utilizing the Diasorin radioimmunoassay using sera. Multiple logistic regression analyses were performed to identify independent risk factors associated with vitamin D deficiency. Results: In our cohort of 391 post-menopausal women with stage I to III breast cancer on AI therapy, the mean vitamin D level was 35 ng/mL, S.D. 12.49. Vitamin D levels were normally distributed in the cohort. Thirty five percent of women were vitamin D deficient, defined as a level less than 30 ng/mL. In our cohort, 73.4% of the participants had vitamin D supplementation documented in their chart; 26.8% of these women were still vitamin D deficient despite supplementation. Adjusting for demographic and clinical variables, non-white patients were more likely to be vitamin D deficient, adjusted odds ratio (AOR) of 2.00, 95% confidence interval (CI) 1.14-3.51, p=.004. Overweight (AOR 3.07, 95% CI 1.77-5.33, p Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-14-11.

This study investigated the effect of storage temperature (0, 3, and 6°C) and duration (2, 4 and 6 weeks) on fruit quality of 'Clutha Gold', 'Moorpark', 'Genevieve' and 'Southern Cross' apricot cultivars grown in New Zealand. After harvest, fruit were sorted based on size, colour and absence of physical injuries. Fruit samples were destructively assessed (penetrometer firmness, °Brix and pH) pre-storage and post-storage (at 20°C) after shelf life of three days for 2- and 6-week storage regimes and after shelf life of 0, 3 and 6 days following a 4-week storage regime. Each fruit was also tasted and scored for juiciness, mealiness and texture acceptability. The storage temperature at which apricot fruit were held significantly affected fruit quality within the first two weeks of storage. Fruit stored at 0°C showed the best overall quality in terms of fruit firmness, juiciness, lack of mealiness, and texture acceptability. There was significant variation in the effect of temperature on the different cultivars studied. Higher storage temperatures (3 and 6°C) were also more detrimental to fruit eating quality. Juiciness decreased and mealiness increased with longer storage duration, except for 'Southern Cross' held at 0°C. Texture acceptability also decreased with longer storage regardless of storage temperature.

Heat shock proteins (HSPs) are potent protectors of cellular integrity against environmental stresses, including toxic microbial products. To investigate the mechanism of HSP-70 cell protection against bacterial lipopolysaccharide (LPS), we established a stable HSP-70 gene-transfected RAW 264.7 murine macrophage model of LPS-induced cell death. Bacterial LPS increases the activity of sphingosine kinase 1 (SK1), which catalyzes formation of sphingosine-1-phosphate (S1P). S1P functions as a critical signal for initiation and maintenance of diverse aspects of immune cell activation and function. When mouse macrophages were incubated with Escherichia coli LPS (1 μg/ml) and sphingosine kinase inhibitor (SKI, 5 μM), 90% of cells died. Neither LPS nor SKI alone at these doses damaged the cells. The LPS/SKI-induced cell death was partially reversed by overexpression of HSP-70 in gene-transfected macrophages. The specificity of HSP-70 in this reversal was demonstrated by transfection of HSP-70-specific siRNA. Down-regulation of HSP-70 expression after transfection of siRNA specific for HSP-70 was associated with increased LPS/SKI-induced cell damage. Overexpression of human or murine HSP-70 (HSPA1A and Hspa1a, respectively) increased both cellular SK1 mRNA and protein levels. Cellular heat shock also increased SK1 protein. These studies confirm the importance of SK1 as a protective moiety in LPS-induced cell injury and demonstrate that HSP-70-mediated protection from cells treated with LPS/SKI is accompanied by upregulating expression of SK1. HSP-70-mediated increases in SK1 and consequent increased levels of S1P may also play a role in protection of cells from other processes that lead to programmed cell death.

BACKGROUND The purpose of this study was to evaluate the prognostic value of maximal standard uptake values (SUVs(max)) from serial fluor-18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in patients with locally advanced nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS From October 2002 to January 2004, 62 patients with locally advanced NPC who underwent (18)F-FDG PET/CT scan before and after radiotherapy were reviewed retrospectively. We examined the association of SUV(max) and the results of long-term follow-up of the patients. RESULTS Patients having tumors with a lower SUV(max) had significantly better 5-year overall survival (OS) (P= 0.0187) and disease-free survival (DFS) (P = 0.0163) than patients with a greater SUV(max). The patients who showed with metabolic complete response had a significantly higher 5-year OS (P = 0.0237) and DFS (P = 0.0186) than patients with metabolic partial response. Poor prognosis was found in patients with the SUV(max) of neck nodes larger than that at the primary tumor site (SUV(max-N) > SUV(max-P)) (P = 0.0440). CONCLUSIONS (18)F-FDG uptake, as measured by the SUV(max) before radiotherapy and metabolic response after radiotherapy, may predict the prognosis in locally advanced NPC. High (18)F-FDG uptake before and after radiotherapy may be useful for identifying patients requiring more aggressive treatment.

In the present work, characterisations such as surface morphology, cross-section image and composition of corrosion scale formed on the P110 steel under turbulent flow conditions with various Cl– concentrations have been studied by means of scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The corrosion medium was the simulated solution of one oil/gas field, saturated with CO2 at 100°C and 4 MPa. The tests were conducted corresponding to various Cl– concentrations and varied flow velocities. It is concluded that Cl– concentration and flow velocity have an important effect on the corrosion scales formed on the samples. In addition, the protective properties and adherence of the corrosion scales were characterised by the analysis of the scale formation and influence mechanisms associated with Cl– concentration and flow velocity. Moreover, a lattice model is created to interpret and illuminate the corrosion process.

It was found that isopropanol as solvent was propitious to the p-xylene electrochemical oxidation, then obtained the 1,4-bis(methoxymethyl) benzene or 1-dimethoxymethyl-4-methyl benzene. When the isopropanol was added in 20 ml, the 1,4-bis(methoxymethyl) benzene or 1-dimethoxymethyl-4-methyl benzene of products was 36.09%. Compared to no isopropanol, the experimental result showed that the total yield of products above can be obviously increased. On the conditions of room temperature and constant current intensity, the reaction was carried out in a single-compartment cell by the use of a pair of graphite plane electrodes. The testing process was tracked by UV-vis spectrum. In succession, we adopted gas chromatography / mass spectrometry and gas oil octane number test to detect the final production. Based on the gas oil octane number test result, the production can be used as the gas oil additive.

This work investigates the effect of temperature on the corrosion product layer of carbon steel exposed to a CO2-containing solution. The measurement techniques, such as scanning electron microscopy with energy dispersive spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy, were used to systematically characterize the morphology and composition of the corrosion product layer. The corrosion rates were calculated by weight loss method. The corrosion mechanisms as a function of temperature are studied and discussed. The results showed that temperature is an important factor in the corrosion rate of carbon steel. Copyright © 2009 John Wiley & Sons, Ltd.

The pitting behavior was investigated on super 13Cr stainless steels in 3.5% NaCl solution in the presence of HAc. The electrochemical measurements including potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and chronoamperometric experiments were carried out, as well as the SEM surface analysis. The parameters such as E corr and I corr were obtained by fitting technique. Moreover, the equivalent circuit model was applied in the analysis of Nyquist plots, and ZsimWin software was used to analyze the EIS data. The results indicate that the pitting corrosion is accelerated with increasing the amounts of HAc. In addition, pitting nucleation and growth mechanisms were described in this work.

In this study, a new model is proposed for predicting the location of the neutral plane inside the shaft space of a building under fire situation. The shaft space of the building is divided into two zones, i.e., fire zone and inner space, in the model. The temperature is assumed uniform in each zone. To validate the proposed model, a parametric numerical study is also carried out by using a computational fluid dynamics (CFD) code, i.e., FDS code. The comparisons between the proposed model and the CFD model are processed and the agreements between the two approaches are satisfied. It is found that the location of the neutral plane is above the mid-height of the building and the simulation results are consistent with the proposed model approximately. The ratio of the neutral plane height to ceiling height depends on the ventilation condition of the fire room greatly, which is found varying between 0.50 and 0.62.

A dynamic tribometer has been successfully developed utilizing torsional Kolsky bar (TKB) technique for tribo pairs subjected to dynamic compression and shear. The dynamic tribometric responses of ground finish (Ra = 0.17 μm) and polished finish (Ra = 0.10 μm) surfaces of silicon carbide (SiC) under compression loading up to 1.5 GPa and shear-sliding velocity to 3.8 m/s have been measured. The experimental results show Coulomb friction behavior. Hardening of shear response is found on both the ground and polished surfaces. Repeating tests on the same tribo-pair demonstrate that steady state shear response on polished surfaces can be achieved by cumulating shear-sliding distance. SEM observation of the tested surface shows that the tested surfaces are microscopically shear-damaged. The similar surface conditions after a relative longer shear-sliding distance on polished surfaces lead to the same steady state frictional coefficient, 0.61, for both finishing surfaces.

Surface X-ray scattering and scanning–tunneling microscopy experiments, performed in situ, are used to investigate the influence of quantum size effects on the growth of Pb on the Si(111)7×7 surface. It is demonstrated that the structure of Pb islands and the associated wetting layer are consistent with the effects of quantum confinement. Moreover, these effects lead to novel behavior for the coarsening evolution of the Pb islands. For example, Ostwald ripening is not observed due to a breakdown of the classical Gibbs–Thomson effect. An unanticipated strong dependence on the deposition flux rate is found and we measure island decay times that are orders of magnitude faster than predicted. These results have important implications for understanding and controlling the growth of nanostructures.

The authors previously identified plasma plasminogen activator inhibitor-1 (PAI-1) level as a quantitative lung injury biomarker in primary graft dysfunction (PGD). They hypothesized that plasma levels of PAI-1 used as a quantitative trait could facilitate discovery of genetic loci important in PGD pathogenesis. A two-stage cohort study was performed. In stage 1, they tested associations of loci with PAI-1 plasma level using linear modeling. Genotyping was performed using the Illumina CVD Bead Chip v2. Loci meeting a p5 × 10(-4) cutoff were carried forward and tested in stage 2 for association with PGD. Two hundred ninety-seven enrollees were evaluated in stage 1. Six loci, associated with PAI-1, were carried forward to stage 2 and evaluated in 728 patients. rs3168046 (Toll interacting protein [TOLLIP]) was significantly associated with PGD (p = 0.006). The increased risk of PGD for carrying at least one copy of this variant was 11.7% (95% confidence interval 4.9-18.5%). The false-positive rate for individuals with this genotype who did not have PGD was 6.1%. Variants in the TOLLIP gene are associated with higher circulating PAI-1 plasma levels and validate for association with clinical PGD. A protein quantitative trait analysis for PGD risk prioritizes genetic variations in TOLLIP and supports a role for Toll-like receptors in PGD pathogenesis.

Dendritic cell factor 1 plays important roles in neural stem cells differentiation and in glioma cells proliferation, migration, and invasion. Here, we used a tetracyclinemdash;inducible system that regulates the expression of Dendritic cell factor 1 in glioma cells. We constructed two tetmdash;inducible vectors, pTREmdash;EGFPmdash;DCF1 and pTREmdash;LJM1mdash;DCF1, by modifying the promoter PCMV. In the absence of tetracycline or doxycycline, the expression of Dendritic cell factor 1 in cells comdash;transfected with pTREmdash;EGFPmdash;DCF1 or pTREmdash;LJM1mdash;EGFPmdash;DCF1 and ptTSmdash;Neo was suppressed through binding of the tetracylinemdash;controlled transcriptional suppressor to tetracycline response element, and the suppression was released by the addition of doxycycline. Our work has laid foundations for potential clinical application of cancer therapy in realizing artificial regulation of gene.

A new experimental method combining dynamic tribometry based on the torsional Kolsky bar technique and three-dimensional surface profilometry that enables characterization of surface topography and wear has been applied to study the dynamic tribological response of closed silicon carbide (SiC) fracture surface pairs under normal compressive stresses up to 1900 MPa. It is found that global sliding of such a tribo-pair occurs when the interfacial shear stress reaches approximately 39% of the applied normal stress. The engaged interfacial asperity pairs mostly undergo shear-induced disengagement as the sliding initiates. However, surface wear-crushing of asperity-occurs at isolated locations and evolves, though at a decreasing rate, as the sliding progresses, resulting in fine interfacial wear debris particles that act effectively as solid lubricant. The transient behavior of the tribo-pair is affected strongly by the interfacial wear debris, whose response is sensitive to the acceleration rather than the velocity of sliding. Despite the variation of transient response from one experiment to another, the steady-state response is essentially Coulombic (linear) over the sliding velocities examined (0.05–3.4 m/s) with an effective kinetic friction coefficient of 0.36. A dynamic friction model allowing acceleration-dependent overstress and relaxation has been worked out. It is demonstrated that the model can capture the key dynamic features observed in the transient response and recover the Coulombic relation for the steady-state response. The significance of these findings for analyzing shear cracking in SiC deformed under confining stresses is also discussed.

A three-dimensional Voronoi polycrystal model for analyzing heterogeneous phenomena and microplasticity in polycrystalline solids has been developed. The crystal modeling employed considers compression-dependent anisotropic elasticity and rate-dependent crystal plasticity. Implemented into the ABAQUS/Standard code, the model is used to investigate the role of microplasticity via 〈1 1 2 0〉{0 0 0 1} basal slip in the response of polycrystalline hexagonal ceramics under uniaxial-strain shock compression. Finite element simulations using a 600-grain polycrystal model and the crystal properties of α-6H silicon carbide are performed and compared with the experimental measurements on the material in its polycrystalline form. The results show that macroscopic flow can evolve through the collective actions of basal-slip-only microplasticity without causing physically unreasonable micromechanical states. The computed volume-averaged response matches the experimental data very well up to a longitudinal stress of ∼20 GPa, including the phenomenon of Hugoniot elastic limit (HEL) and the post-HEL behavior. The results at higher stresses suggest, however, that the stress concentrations due to the evolution of strongly heterogeneous plastic deformation are sufficiently intense to initiate secondary slip systems and/or other microdamages. Issues related to the micromechanisms that may govern the inelastic response of shock-compressed ceramics are discussed in detail.

We have carried out diffuse X-ray scattering measurements of the growth of Pb nanocrystalline islands on Si(1 1 1). Analysis of our data shows that islands growing on an initially rough wetting layer transforms the portion of the wetting layer below them into ordered fcc sites. Therefore, the islands grow directly on top of the Si surface with a disordered wetting layer occupying the region between the islands and, consequently, the island height responsible for the quantum well depth is one layer thicker than reported by LEED and STM. These islands have an extremely good vertical order until the islands coalesce into a closed film. At that point the disorder of the film increases consistent with misfit strain relaxation.

A computational modeling methodology for micromechanical analysis of polycrystalline hexagonal-structured materials is developed. It consists of a microstructural model based on the two-dimensional Voronoi tessellation, constitutive models for compression-dependent non-linear elasticity and crystal plasticity, and a solution technique based on the Eshelby’s method for generalized plane strain. Numerical simulations are carried out to determine if heterogeneous microplasticity is a viable mechanism of deformation in ceramics undergoing uniaxial strain compression. The simulations using model parameters for α-6H silicon carbide show that a limited amount of microplasticity resulting from basal slip alone or basal and prismatic slip is a viable mechanism for the observed material response under shock wave compression. In particular, the predictions based on the basal and prismatic slip assumption match the experimentally measured Hugoniot elastic limit (HEL) and the post-HEL inelastic behavior up to a shock stress of twice the HEL. The assumption of combined basal and prismatic slip results in 24% more mean effective plastic deformation than the assumption of basal slip at twice the HEL. Furthermore, statistical analysis of the longitudinal stress and effective plastic strain distributions shows that the micromechanical states in the polycrystal become increasingly heterogeneous with increase in the applied compression.

We have produced ultrathin epitaxial graphite films which show remarkable 2D electron gas (2DEG) behavior. The films, composed of typically 3 graphene sheets, were grown by thermal decomposition on the (0001) surface of 6H-SiC, and characterized by surface-science techniques. The low-temperature conductance spans a range of localization regimes according to the structural state (square resistance 1.5 kOhm to 225 kOhm at 4 K, with positive magnetoconductance). Low resistance samples show characteristics of weak-localization in two dimensions, from which we estimate elastic and inelastic mean free paths. At low field, the Hall resistance is linear up to 4.5 T, which is well-explained by n-type carriers of density 10^{12} cm^{-2} per graphene sheet. The most highly-ordered sample exhibits Shubnikov - de Haas oscillations which correspond to nonlinearities observed in the Hall resistance, indicating a potential new quantum Hall system. We show that the high-mobility films can be patterned via conventional lithographic techniques, and we demonstrate modulation of the film conductance using a top-gate electrode. These key elements suggest electronic device applications based on nano-patterned epitaxial graphene (NPEG), with the potential for large-scale integration., Comment: 5 pages, figure files: figure1.eps, figure2a.eps, figure2b.eps, figure3.eps

A Kolsky torsion bar is utilized successfully in a novel rheometric experiment for measuring the transient large-strain response of polymer melts under high shear-rate loading. A molten low-density polyethylene is studied with the new technique. The results show that the high-rate shear response of the material has an instantaneous rate dependence that may not be discernible at low rates and a strain-dependent hardening that saturates at large strains instead of fading. The usefulness of the technique and the significance of the findings are discussed in comparison with a modified rubberlike liquid theory and high-rate capillary measurements for low-density polyethylene melts.

The Kolsky torsion bar technique has been utilized successfully to develop a new compression-shear recovery experiment for dynamic tribometry of closed fracture surface pairs. This new experimental design enables combined dynamic compression and shear loading and preserves the residual specimen surface after a single cycle of loading. The experimental design was first verified through a series of dynamic friction experiments on flat 7075-T6 aluminum alloy surface pairs. The technique was then applied to study the dynamic tribological response of closed fracture surface pairs of the same material in conjunction with surface topography examination. It was found that the pre-sliding response depends primarily on normal stress and roughness of as-fractured surface. The response after the initiation of frictional sliding displays an exponential decay with increasing sliding displacement. The long-time steady-state response (if achieved) depends predominantly on normal stress. The results also show that a sufficiently high normal stress may suppress frictional sliding between the fracture surfaces giving rise to a dynamic plastic deformation continuous across the interface. An empirical model describing the key experimental observations is proposed and evaluated against the experimental data. The implication of the findings on shear cracking under high confining stress is discussed.

Exact solutions for interfacial edge dislocations in an anisotropic bicrystal under plane strain are derived in elementary closed-form by the method of image dislocations. The stresses in the two adjoining crystals, which may have dissimilar elastic constants and/or dissimilar material axis orientations, are shown to be given by the sum of three rational functions of first to second order degree polynomials. Numerical results for an interfacial glide edge dislocation in several bicrystals of hexagonal ceramics show complex dependence on the material and orientational inhomogeneities. In particular, the interfacial stresses when plotted against the c-axis orientations of the two crystals are shown to possess extrema, saddle points, and a center of symmetry/antisymmetry.

A new rolling technique, so called ‘inscribed rolling’, has been tested for improvements on superconductivity of PIT/BSCCO. This technique allows deforming of the BSCCO/Ag composite in a way that is similar to flat rolling using large radius roller. A widening of tape and uniform core distribution have been obtained and an improved current density has also been measured from MF-BSCCO tapes.

It has been observed in plate impact experiments that some brittle solids may undergo elastic deformation at the shock wave front, and fail catastrophically at a later time when they are shocked near but below the apparent Hugoniot elastic limit. Because this phenomenon appears to have features different from those of usual inelastic waves, it has been interpreted as the failure wave. To design an effective numerical procedure for simulating impact failure responses, a three-dimensional computational damage model is developed in this paper. The propagation of the failure wave behind the elastic shock wave is described by a non-linear diffusion equation. Macroscopic shear-induced dilatancy is assumed and treated as a one-to-one measure of the mean intensity of microcracking. The damage evolution in time is determined based on the assumption that the deviatoric strain energy in the elastically compressed material (undamaged) is converted, through the damaging process, into the volumetric potential energy in the comminuted and dilated material. For the ease in large-scale simulations, the coupled damage diffusion equation and the stress wave equation are solved via a staggered manner in a single computational domain. Numerical solutions by using both the finite element method and the material point method, i.e. with and without a rigid mesh connectivity, are presented and compared with the experimental data available. It is shown that the model simulations capture the essential features of the failure wave phenomenon observed in shock glasses, and that the numerical solutions for localized failure are not mesh-dependent.

All of the thermal and elastic constants of the high-aspect ratio, negative, UV resist, SU8 coating were carried out, and the compliance matrix of the coating was obtained. DSC, TGA, TMA, and DMTA techniques were utilized to study the thermal properties of the material. The in-plane thermal expansion coefficient (TEC) (α1) was determined by TMA, and the glass transition behavior was studied by DMTA. The TGA study provided information about the thermal stability of the material, and DSC was applied to study the thermal calorimetric properties of the material. The in-plane Young's modulus (E 1) was measured by tensile tests. The residual stresses of a 1D stretched ribbon sample and a 2D stretched membrane sample were measured by vibrational holography tests, and the in-plane Poisson's ratio (ν1) was also determined by holography. The out-of-plane Poisson's ratio (ν2) was obtained by high pressure gas dilatometry measurements. The bulk compressibility (κ) and the volumetric TEC (α v ) of the material were measured by a pressure-volume-temperature (PVT) apparatus. Finally, the out-of-plane properties, including the out-of-plane TEC (α2) and the out-of-plane Young's modulus (E 2), were calculated from the measured in-plane properties and the volumetric properties. Therefore, the compliance matrix of the studied SU8 coating could be obtained.

A new water purification equipment was introduced, especially the section of spiral lamellas. Utilization of spiral lamellas made the sedimentation space reach to 100%, not only improving sedimentation efficiency and reducing the cover space, but also saving investment. Production test results showed that the new water purification equipment with spiral lamellas had characteristics of excellent treatment efficiency and high shock resistant capacity. As the treatment water volume was 240 m3/d, when the turbidity, CODMn and UV254 were 203 NTU, 1.90 mg/L and 0.030 cm-1 in raw water, they were 0.32 NTU, 0.72mg/L and 0.011 cm-1 respectively in effluent water, which could fully meet the drinking water hygiene requirement.

Insect removal from kiwifruit is important for improving access to overseas markets. Insect removal from kiwifruit by physical treatments such as high pressure washing is hugely successful but kiwifruit packing is carried out “dry”. Therefore, one potential option is the use of ‘air-knife’ blowers to remove insects. A system with air-knives from the sides and top that was mounted over a single-lane Compac grader was able to remove over 90% of artificially inoculated diapausing two-spotted mites (≈ 85/fruit). The difference in pest levels between untreated ‘Hayward’ kiwifruit fruit naturally infested with a wide range of insects (n=2194) and fruit exposed to air-knives (n=2204) was: mealybug 100%, beetle/weevils 91—100%, oribatid mites 93%, tuckerellid mites 98%, unidentified mites 88% , booklice 86%, thrips 74— 100%, Collembola 63%, cockroaches 100%, spiders 43%, scale insects 40%. Air-knives had no noticeable effect on ‘Hayward’ or ‘Zesy002’ (Gold3) fruit quality. These results indicate that air-knives using a high air-flow/low-pressure system can effectively remove high rates of “mobile” insects and first-instar scale insects, and can probably be implemented logistically and economically from a commercial perspective.

It has been known that environmental enrichment leads to better learning and memory in mice. However, the molecular mechanisms are not known. In this study, we used the 10th–12th of the NR2B transgenic (Tg) lines, in which the NMDA receptor function is enhanced via the NR2B subunit transgene in neurons of the forebrain, to test the hypothesis of the involvement of NMDA receptor function in enrichment-induced better learning and memory. Consistent with our previous results, both larger long-term potentiation (LTP) in the hippocampus and superior learning and memory were observed in naive NR2B Tg mice even after the 10th–12th generation of breeding. After enrichment, wild-type mice exhibited overall improvement in their performances in contextual and cued conditioning, fear extinctions, and novel object recognition tasks. Interestingly, the same enrichment procedures could not further increase the performance of NR2B Tg mice in contextual conditioning, cued conditioning, or fear extinction, thereby indicating that enhanced NMDA receptor function can occlude these enrichment effects. However, we found that in the novel object recognition task enriched NR2B Tg mice exhibited much longer recognition memory (up to 1 week), compared to that (up to 3 days) in naive NR2B Tg mice. Furthermore, our biochemical experiments showed that enrichment significantly increased protein levels of GluR1, NR2B, and NR2A subunits of glutamate receptors in both wild-type and NR2B Tg mice. Therefore, our results suggest an interactive nature of molecular pathways involved in both environmental and genetic NMDA receptor manipulations for enhancing learning and memory.

Compression and shear wave experiments using plate impact loading were conducted on polycrystalline silicon carbide (SiC). The material was subjected to combined compression-shear loading to peak compressive stresses ranging from 3 to 18 GPa. The compression (shock) wave profiles and the propagation velocities of shear and longitudinal release waves in the shocked SiC were measured using in situ, electromagnetic velocity gauges. The Hugoniot elastic limit (HEL) of the material was found to be 11.5±0.4 GPa. The measured wave velocities were used to determine the elastic moduli of the material as functions of density compression in the shocked state. The data were further analyzed to obtain the mean stress response of the SiC under uniaxial-strain compression. The longitudinal and mean stress results completely characterize the material stress state. Numerical simulations were also carried out to verify the peak-state data analysis. Our results show that the Poisson’s ratio of the material increases with el...

Mechanisms of corrosion fatigue crack initiation by pitting in high-strength, 7000-series aluminum alloys were studied. The alloys used were Al 7075-T7351 (UNSA97075) and Al 7050-T7451 (UN...