Search

The present paper presents finite element models to describe machine dynamics, such as electron beam (EB) generation in an EB gun, EB scanning on the surface of an ingot, melting process of the ingot, and vaporisation and deposition on the surface of a substrate during EB–PVD process. Based on physical models, the finite element models relate the input power to the EB gun and the temperature profile of the ingot surface, the temperature profile to the shape of vapour plume, and the vapour distribution to the coating thickness. The two deposition process models have been investigated for predicting the coating thickness and compared to experiments performed for simple shaped substrates. With preliminary studies, it is found that the presented models are suitable for a cost efficient computation and can aid in assessing process parameters.

The Korea Superconducting Tokamak Advanced Research (KSTAR) central solenoid model coil (CSMC) was tested at the National Fusion Research Center (NFRC) to verify the design and manufacturing engineering and to ensure reliable operation. The CSMC reached 8.6 T at 20 kA DC operation successfully. We also assessed the AC loss of the CSMC by means of both a sinusoidal wave with a DC offset as well as a triangular pulse. We derived a friction factor correlation of CSMC at room temperature and at cryogenic temperature (4 ~ 6 K). We also investigated the variation of the friction factor during current charging. The KSTAR PF coil simulation code was validated with inlet and outlet helium temperature, mass flow rate, and pressure drop from the experimental results. The operation temperature margin of the CSVT coil of KSTAR was calculated with the revised KSTAR PF coil simulation code.

Background Increased plasminogen activator inhibitor-1 (PAI-1) concentrations are found in bronchoalveolar lavage (BAL) fluids from patients with ventilator-associated pneumonia or acute respiratory distress syndrome. The authors hypothesized that PAI-1 concentrations were associated with increased mortality in patients with either Pseudomonas aeruginosa-induced ventilator-associated pneumonia or tracheobronchial colonization. Methods In a prospective cohort study, daily aspirates from intubated patients were cultured for P. aeruginosa. Positive patients had blind BAL (bBAL) that was processed for biomarker concentrations. Secretion of type III secretion cytotoxins were also analyzed from the P. aeruginosa strains. Results Thirty-three patients were enrolled. Ten of the 33 patients died. bBAL PAI-1 concentrations were significantly increased in nonsurvivors compared with survivors (31.7 vs. 3.4 ng/ml, P = 0.001 for hospital mortality; 35.9 vs. 4.7 ng/ml, P = 0.02 for 28-day mortality). Even when acute respiratory distress syndrome patients were excluded, there was a significant difference between the survivors and nonsurvivors for bBAL PAI-1 concentrations (P = 0.005). Eighty-three percent of P. aeruginosa strains isolated from patients with high concentrations of bBAL PAI-1 also had strains that secreted cytotoxins. Conclusions PAI-1 concentrations in bBALs correlated with mortality in ventilated patients with positive cultures for P. aeruginosa. Elevated bBAL PAI-1 concentrations also correlated with the secretion of type III exotoxins by P. aeruginosa.

This volume of collected essays reflects on various aspects of language, text, and interpretations of war and peace in the Dead Sea Scrolls and other Second Temple Jewish literature, with special close attention set on the Qumran War Scroll.

A computer model was developed to perform a thermodynamic analysis of the transcritical carbon dioxide cycle with two-stage compression and intercooling. In typical two-stage compression with intercooling applications, the intercooler serves the purpose of cooling the fluid to the lowest possible temperature before it enters the second-stage compressor. This paper presents the results of the system analysis of the transcritical carbon dioxide cycle with two-stage compression and intercooling (intercooler cycle) and identifies the pressure ratios that provide maximum system efficiency. The results show that the coefficient of performance (COP), curves of the intercooler cycle are different from the ‘typical bell curve behaviours’ that are observed when plotting the COP versus the intermediate pressure with assumptions of isentropic and real compression process.

A simulation model for a piston-cylinder type expansion device in which the linear motion of the piston is converted to the rotational motion of a crank via a connecting rod was developed for its use in a transcritical CO2 cycle. The model is based on lubrication theory with an assumption that the piston ring is a slippery bearing. This model has been used to verify the proper operation of the device in a prototype application and to identify the loss mechanisms of the device in the design stage. In addition, an analysis of the device has been conducted using this theoretical model for the device as installed in a prototype cycle as reported in a companion part I paper.

Carbon dioxide is receiving strong consideration as an alternative refrigerant substituting hydroclorofluorocarbons (HCFCs) and chlorofluorocarbons (CFCs) due to its zero ozone depletion potential and negligible global warming potential. The system performance of CO2 systems, however, is typically poor compared to the current conventional air conditioning systems using HCFC or CFC. One of the most effective ways to achieve parity with CFC and HCFC systems is to replace the expansion valve with an expansion device that minimizes entropy creation and allows for energy recovery during the expansion process. A piston-cylinder type work output expansion device was designed, constructed and tested as part of the study reported here. The first-cut prototype device is based on a highly modified small four-cycle, two-piston engine that is commercially available. The work-producing expander replaced the expansion valve in an experimental transcritical CO2 cycle and increased the system performance by up to 10% as characterized by COP. The prototype device was not meant to be a final product, but provided valuable insight and experimental results to validate a detailed simulation model of the device. The model and corresponding theoretical analysis are presented in a companion part II paper.

Using nitrogen radio-frequency (RF) plasma operated in low-pressure metal-organic chemical vapor deposition (LP-MOCVD), ZnSe:N epilayers were grown. Their optical and electrical properties were investigated with photoluminescence (PL) and deep level transient spectroscopy (DLTS). PL spectra of ZnSe:N epilayers show that acceptor-bound exciton (I1) at 2.792 eV, donor-acceptor pair (DAP) at 2.65 ∼ 2.70 eV and its phonon replica in the lower energy side were dominant at low temperature. As increasing temperature, the intensity of the DAP line decreases rapidly compared to that of the exciton line. In addition, the free (electron)-to-acceptor (FA) emission appears on the high energy side of the DAP emission due to the partial ionization of shallow donors above 30 K. From the temperature dependence of the PL peak intensities, it can be seen that the activation energy of exciton line (22.3 meV) is in good agreement with the binding energy of the free exciton (21 meV). We investigate electrical properties of nitrogen-doped ZnSe films by measuring capacitance-voltage characteristic curve and DLTS. We have carried out DLTS to study deep hole traps in ZnSe:N epilayer and hole traps with the activation energy of 470 ∼ 790 meV were detected. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Self-assembled ZnSe quantum dots (QDs) embedded in ZnS were grown by metal-organic chemical vapour deposition and investigated with atomic-force microscopy (AFM) and photoluminescence (PL) measurements. Lens-shaped ZnSe QDs with the height of 1–2.4 nm and the radius of 25–37 nm are observed through the AFM measurements. The size and areal density of QDs increases as ZnSe deposition is increased. PL spectra of ZnSe QDs show consistent blueshifts due to quantum confinement effects. A simple model taking into account the lens shape of ZnSe QDs is introduced to calculate the quantum confinement effects in ZnSe QDs. Obtained excitonic ground state transition energies are in good agreement with the experimental PL peaks, which proposes that the model is adequate to describe the quantum confinement effect in lens-shaped ZnSe QDs. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This experiment was carried out to evaluate the value of total mixed fermentation feeds(TMFF) as completely mixed ration and to observe the effect of various kinds of TMFF on the palatability, feed intake, and milk performance in Holstein cows. The dry matter (DM) content of TMFF used in the experiment was 23.98-28.42% range, and CP, TDN, ADF and NDF were 16.219.2%, 58.3-65.1%, 34.4-39.6% and 46.949.9% levels, respectively. The relative feed value (RFV) in rape-, alfalfa-, grass-, oat-, corn-TMFF groups were 138.6, 133.9, 116.5, 111.8, 111.4 and 108.1, respectively. Among these groups, RFV of rye-TMFF group was lowest. Dry matter disappearance(DMD) showed 0.8.9% to the all kinds of TMFF groups. The pH was 3.89.87 and -N concentration was 6.93-8.66 mg/. The acetic acid concentration in the raw material of TMFF showed low level of 0.190.57%, lactic acid showed high level of 1.173.21% and butyric acid was very high as 0.030.32%. Therefore, these results provide evidence that the quality of TMFF was not so bad. In the daily fresh matter intake on the alfalfa-, grass-, rape-, corn-, oats- and rye-TMFF were showed 62.85, 60.48, 58.04, 57.11, 54.61 and 45.74 kg respectively. All TMFF showed high palatability as daily dry matter intake of 1.95 to 2.90% by body weight of experimental cows. Body condition score(BCS) was gradually increased in during 60 days of the experiment term. Average daily gain(ADG) showed about 140.0326.7g. In alfalfa-TMFF group, the ADG was higher than in the other groups (p18.95 kg in all groups. Among these groups, alfalfa-TMFF group was highest(P4.79% and the level was high in order of rape-, grass-, corn-, alfalfa-, rye- and oats-TMFF. Milk protein was highest in forage-TMFF and level of lactose in milk was approximately 4.56% in overall groups. Solid non fat(SNF) and total solid(TS) contents were 8.75% and 12.8%, respectively. However, milk composition was not significantly affected by TMFF.

A perturbed Cantor set (without the uniform boundedness condition away from zero of contraction ratios) whose upper Cantor dimension and lower Cantor dimension coincide has its Hausdorff dimension of the same value of Cantor dimensions. We will show this using an energy theory instead of Frostman's density lemma which was used for the case of the perturbed Cantor set with the uniform boundedness condition. At the end, we will give a nontrivial example of such a perturbed Cantor set.

The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the NIST research reactor (aka NBSR); a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a preliminary version of the Safety Analysis Report (SAR) that would be submitted to the U.S. Nuclear Regulatory Commission (NRC) for approval prior to conversion. The report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis in any conversion SAR is to explain the differences between the LEU and HEU cores and to show the acceptability of the new design; there is nomore » need to repeat information regarding the current reactor that will not change upon conversion. Hence, as seen in the report, the bulk of the SAR is devoted to Chapter 4, Reactor Description, and Chapter 13, Safety Analysis.« less

High density experiments with 2.45 GHz lower hybrid current drive (LHCD) in EAST are analyzed by means of simulation and modeling, showing that parametric instabilities (PI), collisional absorption and density fluctuations in the edge region could be responsible for the low CD efficiency at high density. In addition, recent LHCD results with 4.6 GHz are presented, showing that lower hybrid wave can be coupled to plasma with low reflection coefficient, drive plasma current and modify the current profile, and heat plasma effectively. The related results between two systems (2.45 GHz and 4.6 GHz) are also compared, including CD efficiency and PI behavior. © 2015 AIP Publishing LLC.

The Samsung superconductor test facility (SSTF) at SAIT (Samsung Advanced Institute of Technology, Taejon, Korea) is to be equipped with a 740 mm inner diameter superconducting split magnet (MC), which provides the background field B/sub 0/ = 8 T with ramp rate up to 3 T/s at 250 mm gap between the magnet halves. A smaller superconducting split magnet (BC) with the diameter 400 mm will be installed coaxially inside of MC to produce an additional fast variation of magnetic field with ramp rate up to 20 T/s and amplitude /spl plusmn/1 T. In order to reduce the coupling between MC and BC magnets and to avoid the MC disturbance by the fast changing stray field from BC a cancellation coil (CC) is to be provided. The comparison of an active superconducting CC charged in series with BC and a passive cryoresistive, LHe cooled CC (PCC) of which the current is induced during the fast BC discharge only has been made. The advantages of the PCC concept are discussed. The amount of LHe evaporated by PCC (charged for a short time) is estimated to be 3 to 5 liter/pulse. Recovering time for PCC is 5 to 10 min.

This report documents calculations of the fuel cladding temperature during loss-of-coolant accidents in the NBSR. The probability of a pipe failure is small and procedures exist to minimize the loss of water and assure emergency cooling water flows into the reactor core during such an event. Analysis in the past has shown that the emergency cooling water would provide adequate cooling if the water filled the flow channels within the fuel elements. The present analysis is to determine if there is adequate cooling if the water drains from the flow channels. Based on photographs of how the emergency water flows into the fuel elements from the distribution pan, it can be assumed that this water does not distribute uniformly across the flow channels but rather results in a liquid film flowing downward on the inside of one of the side plates in each fuel element and only wets the edges of the fuel plates. An analysis of guillotine breaks shows the cladding temperature remains below the blister temperature in fuel plates in the upper section of the fuel element. In the lower section, the fuel plates are also cooled by water outside the element that is present due to themore » hold-up pan and temperatures are lower than in the upper section. For small breaks, the simulation results show that the fuel elements are always cooled on the outside even in the upper section and the cladding temperature cannot be higher than the blister temperature. The above results are predicated on assumptions that are examined in the study to see their influence on fuel temperature.« less

We describe the oldest tracks of web-footed birds from the Early Cretaceous in South Korea. The tracks are characterized by a wide divarication angle and a long reversed hallux. The web is semipalmate and restricted to the proximal portion of the three forward digits. The tracks from the Early Cretaceous in South Korea are smaller than those of the Late Cretaceous, therefore confirming the trend of size increasing in the early evolution of birds as shown by skeletal fossils. The discovery of web-footed tracks with abundant non-web-footed tracks indicates that there was a considerable diversification of shore birds as early as the Early Cretaceous.

ZnS x Se 1-x (x < 0.18) random alloy and ordered alloy were grown on GaAs (001) substrate by metalorganic chemical vapor deposition in ALE mode (MOCVD-ALE) using dimethylzinc, H 2 Se and H 2 S as source materials. In order to investigate the strain effect of ZnS x Se 1 -x epilayers, heavy hole (hhx) and light hole (lhx) exciton peaks in PL spectra were monitored as a function of S composition. The identification of hhx and lhx peaks was confirmed by photoreflectance spectroscopy. The S composition at which lattice matching took place was determined to be 5.6%. The full-width at half-maximum (FWHM) of hhx peak increased and deep-level emission appeared in the PL spectra as the S composition increased. For the ordered alloy, the FWHM of exciton peak was narrower than that for the random alloy and the deep level emission was suppressed. An analysis of broadening of the exciton line show that the optical properties of random alloy are influenced by alloy potential and that the alloy potential fluctuation is significantly constrained in the ordered alloy.

At the order of 1/m_b^3, the B meson lifetimes are controlled by the hadronic matrix elements of some four-quark operators. The nonfactorizable magnitudes of these four-quark operator matrix elements are analyzed by QCD sum rules in the framework of heavy quark effective theory. The vacuum saturation for color-singlet four-quark operators is justified at hadronic scale, and the nonfactorizable effect is at a few percent level. However for color-octet four-quark operators, the vacuum saturation is violated sizably that the nonfactorizable effect cannot be neglected for the B meson lifetimes. The implication to the extraction of some of the parameters from B decays is discussed. The B meson lifetime ratio is predicted as \tau(B^-)/\tau(B^0)=1.09\pm 0.02. However, the experimental result of the lifetime ratio \tau(\Lambda_b)/\tau(B^0) still cannot be explained., Comment: 20 pages, latex, 6 figures, discussion on non-factorizable effect of the four-quark condensate added, to appear in Phys. Rev. D57 (1998)

Pancreatic islets from DBA/2 mice infected with the D variant of encephalomyocarditis (EMC-D) virus revealed lymphocytic infiltration with moderate to severe destruction of pancreatic beta cells. Our previous studies showed that the major population of infiltrating cells at the early stages of infection is macrophages. The inactivation of macrophages prior to viral infection resulted in the prevention of diabetes, whereas activation of macrophages prior to viral infection resulted in the enhancement of beta-cell destruction. This investigation was initiated to determine whether macrophage-produced soluble mediators play a role in the destruction of pancreatic beta cells in mice infected with a low dose of EMC-D virus. When we examined the expression of the soluble mediators interleukin-1 beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), and inducible nitric oxide synthase (iNOS) in the pancreatic islets, we found that these mediators were clearly expressed at an early stage of insulitis and that this expression was evident until the development of diabetes. We confirmed the expression of these mediators by in situ hybridization with digoxigenin-labelled RNA probes or immunohistochemistry in the pancreatic islets. Mice treated with antibody against IL-1beta or TNF-alpha or with the iNOS inhibitor aminoguanidine exhibited a significant decrease in the incidence of diabetes. Mice treated with a combination of anti-IL-1beta antibody, anti-TNF-alpha antibody, and aminoguanidine exhibited a greater decrease in the incidence of disease than did mice treated with one of the antibodies or aminoguanidine. On the basis of these observations, we conclude that macrophage-produced soluble mediators play an important role in the destruction of pancreatic beta cells, resulting in the development of diabetes in mice infected with a low dose of EMC-D virus.

Malignant peripheral nerve sheath tumors are rare spindle-cell sarcomas derived from Schwann cells or pluripotent cells of the neural crest. They arise from the spinal roots, peripheral nerves, brachial and lumbosacral plexi, cranial nerves and terminal nerve fibers within soft tissue, intestine, lung and bone. These tumors recur either locally, or metastasize distally. Most of these tumors occur in association with neurofibromatosis type 1. Spinal cord metastasis from malignant nerve sheath tumors associated with neurofibromatosis type 1 is very rare. We describe a rare case of near-total spinal cord metastasis in a patient with malignant nerve sheath tumor in the absence of neurofibromatosis, and highlight the microscopic findings and natural history of this disease process.

The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the National Bureau of Standards Reactor (NBSR). The NBSR is a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a planning document for the conversion Safety Analysis Report (SAR) that would be submitted to, and approved by, the Nuclear Regulatory Commission (NRC) before the reactor could be converted.This report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis herein is on the SAR chapters that require significant changes as a result of conversion, primarily Chapter 4, Reactor Description,more » and Chapter 13, Safety Analysis. The document provides information on the proposed design for the LEU fuel elements and identifies what information is still missing. This document is intended to assist ongoing fuel development efforts, and to provide a platform for the development of the final conversion SAR. This report contributes directly to the reactor conversion pillar of the GTRI program, but also acts as a boundary condition for the fuel development and fuel fabrication pillars.« less

A preliminary conceptual design study for Korean DEMO Reactor (K-DEMO) as an activity for Korean Fusion Energy Development Promotion Law (FEDPL) enacted in 2007 was started. A solid-type breeding blanket is the preliminary blanket concept in K-DEMO. As the candidates for the coolant of K-DEMO blanket, helium and water are under investigation through a comparative study of neutronics analysis. The preliminary concept design for inboard and outboard-side blankets for K-DEMO based on the present engineering feasibility has been carried out. The inboard and outboard-side blankets assume the form of several segmented blanket modules. In this work, the dimension for both inside and outboard-side blankets in the K-DEMO is essentially the same. A breeding blanket with a new cooling method, so-called a plate-type blanket, is proposed. In this concept, the plate-type blanket consists of separated individual rectangular parallelepiped cases for breeders and multipliers without a separate pipe system for cooling flow paths. This paper describes the current status of K-DEMO blanket conceptual design study.

Strain effects on sizes and emission energies of ZnSe∕ZnS quantum dots (QDs) have been investigated. The initial strain in the ZnSe QD layer was altered by adjusting the thickness of the ZnS buffer. Consistent blueshifts of the ground-state emission from 4 monolayer ZnSe QDs were observed with increasing the thickness of the ZnS buffer from 20 to 40nm. Atomic-force microscopy revealed that the blueshifts are due to a continuous QD size reduction. We estimated the emission energy as a function of the initial strain in the ZnSe QD layer, which shows that the band-gap engineering is possible through the strain modification.

Background:We surveyed the podiatric medicine professional and academic leadership concerning podiatric medicine professionals as disaster surge responders.Methods:All US podiatric medical school deans and state society presidents were mailed a self-administered structured questionnaire. The leaders were asked to complete the questionnaire and return it by mail; two repeated mailings were made. Descriptive statistics were produced, and differences between deans and society presidents were tested by the Fisher exact test.Results:The response rate was 100% for the deans and 53% for the society presidents. All of the respondents agreed that podiatric physicians have skills applicable to catastrophe response, are ethically obligated to help, and should receive additional training in catastrophe response. Deans and society presidents agreed with the statements that podiatric physicians should provide basic first aid and place sutures, obtain medical histories, and assist with maintaining infection control. With one exception, all of the society presidents and deans agreed that with additional training, podiatric physicians could interpret radiographs, start intravenous lines, conduct mass casualty triage, manage a point of distribution, prescribe medications, and provide counseling to the worried well. There was variability in responses across the sources for training.Conclusions:These findings suggest that deliberations regarding academic competencies at the podiatric medical school level and continuing education should be conducted by the profession for a surge response role, including prevention, response, mitigation, and recovery activities. After coordination and integration with response agencies, podiatric medicine has a role in strengthening the nation’s catastrophic event surge response. (J Am Podiatr Med Assoc 103(1): 87–93, 2013)

Effects of growth condition of titanium interlayer and sputter-etching before its deposition on adhesion of titanium nitride films grown onto high speed steel substrates by RF (13.56 MHz) plasma-assisted chemical vapor deposition were investigated. Adhesion of TiN film increased with sputtering pressure for deposition of the interlayer. Preferred orientation (002) of the interlayer resulted in poor adhesion of TiN film. Proper sputter-preetching gave rise to adhesion up to 45 N and the film demonstrated a cohesive flaking mode during scratch test.

Self-assembled ZnSe/ZnS quantum dots (QDs) have been grown in the Stranski–Krastanov (S–K) mode using a metalorganic chemical vapor deposition technique under the atomic-layer epitaxy mode. Atomic-force-microscopy measurements on the uncapped ZnSe/ZnS QDs reveal that lens-shaped ZnSe QDs are formed after 1–2 monolayer ZnSe is deposited. The ZnSe QDs are estimated 1–2 nm in height and 25–35 nm in radius. The temperature-dependent behavior of confined carriers in the ZnSe QDs has been investigated through photoluminescence (PL) measurements. PL spectra show a substantial PL linewidth narrowing accompanied by a large redshift of the emission peak energy with increasing temperature. This unusual temperature-dependent behavior is interpreted as the dot-to-dot carrier transfer through the wetting layer, which is common to QDs grown in the S–K mode.

The purpose of this study was to determine the level of care of Parkinson's disease patients based on the 10 American Academy of Neurology quality measures. We reviewed 1,367 charts and final analysis was completed on 123 subjects. A total of 1,461 outpatient neurology visits from 33 neurologists were reviewed and 544 were included in the final analysis. Out of all 10 quality measures (13 individual questions addressed), "annual review of Parkinson's medications" was the most frequently documented (97.2%) and "annual review of safety issues appropriate to the patient's stage of disease" was the least frequently documented item (7.2%). Movement disorders specialists recorded significantly more items than other neurologists (4.7 ± 2.86 vs 3.3 ± 1.97, p = .0437); the provider with the highest number of items addressed was a movement disorders nurse practitioner (8.22 out of 13). None of the patient characteristics influenced the rates of documentation of the 10 quality measures. The wide variation of documentation rates could be addressed by comprehensive standardized templates to be reviewed and updated at each visit.

Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a model of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at lowmore » power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.« less

The 12kV-400V dc-dc stage of a distribution level solid state transformers (SST) has been under research and development. Development of a 15kV SiC Mosfet allows a single stage of the dc-dc converter to operate at medium voltage at an operating frequency of over 20kHz. Nonetheless, the high rising and falling time during pulse switching in the dual active bridge operation is another significant obstacle to realize this technology. In order to understand and predict the frequency response with pulse switching and consider common-mode response via circuit analysis accurately, lumped-element equivalent circuit model has been developed for broadband coaxial winding transformer (CWT) with analytic expressions. The simple lumped-element equivalent circuit introduced in this paper has been verified by measurement results from a prototype for a medium-voltage (MV) and high frequency (HF) coaxial winding power transformer up to the frequency where the length of the coaxial body is a quarter of a wavelength and further study up to 30MHz has been described.

Health-related quality of life (HRQOL) is an important treatment outcome for head and neck cancer (HNC) patients. By ascertaining the most important HNC HRQOL issues, research and practice can be directed toward enhancing patient QOL.A cross-sectional study of 46 ENT clinic HNC patients in Puerto Rico (PR) was completed. The European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 (general QOL), and the QLQ-HN35 (HNC QOL) instruments were administered. Correlations and multivariable regressions were separately conducted for QLQ-HN35 variables on the three QLQ-C30 outcome variables: overall health, overall QOL, and the global health/QOL domain.Correlation findings included statistically significant negative correlations between the three QLQ-C30 outcome variables and the QLQ-HN35 variables pain, swallowing, social eating, social contact, and sexuality. Multivariable linear regression identified statistically significant inverse indicators of the outcomes: (1) "lessening of sexuality" with "overall health" (p= 0.02), (2) "problem with social eating" (p= 0.023), "taking pain killers" (p= 0.025), and "problem with social contact" (p= 0.035) with "overall QOL," and (3) "problems with social eating" (p0.009) and "taking pain killers" (p= 0.016) with the "global health/QOL" domain.We conclude that problems with pain, social eating, social interactions, and loss of sexuality are critical indicators of degraded HRQOL in HNC patients living in Puerto Rico. Our results add to the overall knowledge base regarding QOL among HNC patients. The promise of improved QOL for the HNC patient is attainable through additional research in conjunction with advances in clinical treatments and patient management protocols.

Fast gain recovery observed in quantum-dot semiconductor-optical-amplifiers (QDSOAs) is useful for amplifying high-speed optical signals. The small but finite slow recovery component can deteriorate the signal amplification due to the accumulation of gain saturation during 10 Gb/s operation. A study of the gain recoveries and pattern effects in signals amplified using a 1.5 mu m InAs/InGaAsP QDSOA reveals that the gain recovery is always fast, and pattern-effect-free amplification is observed at the ground state. However, at the excited state, the slow component increases with the current, and significant pattern effects are observed. Simulations of the pattern effects agreed with the observed experimental trends. (C) 2012 Optical Society of America

Background In Puerto Rico, relative to the United States, a disparity exists in detecting oral precancers and early cancers. To identify factors leading to the deficit in early detection, we obtained the perspectives of San Juan healthcare practitioners whose practice could be involved in the detection of such oral lesions. Methods Key informant (KI) interviews were conducted with ten clinicians practicing in or around San Juan, Puerto Rico. We then triangulated our KI interview findings with other data sources, including recent literature on oral cancer detection from various geographic areas, current curricula at the University of Puerto Rico Schools of Medicine and Dental Medicine, as well as local health insurance regulations. Results Key informant-identified factors that likely contribute to the detection deficit include: many practitioners are deficient in knowledge regarding oral cancer and precancer; oral cancer screening examinations are limited regarding which patients receive them and the elements included. In Puerto Rico, specialists generally perform oral biopsies, and patient referral can be delayed by various factors, including government-subsidized health insurance, often referred to as Reforma. Reforma-based issues include often inadequate clinician knowledge regarding Reforma requirements/provisions, diagnostic delays related to Reforma bureaucracy, and among primary physicians, a perceived financial disincentive in referring Reforma patients. Conclusions Addressing these issues may be useful in reducing the deficit in detecting oral precancers and early oral cancer in Puerto Rico.

Bacterial communities in the airways of cystic fibrosis (CF) patients are, as in other ecological niches, influenced by autogenic and allogenic factors. However, our understanding of microbial colonization in younger versus older CF airways and the association with pulmonary function is rudimentary at best. Using a phylogenetic microarray, we examine the airway microbiota in age stratified CF patients ranging from neonates (9 months) to adults (72 years). From a cohort of clinically stable patients, we demonstrate that older CF patients who exhibit poorer pulmonary function possess more uneven, phylogenetically-clustered airway communities, compared to younger patients. Using longitudinal samples collected form a subset of these patients a pattern of initial bacterial community diversification was observed in younger patients compared with a progressive loss of diversity over time in older patients. We describe in detail the distinct bacterial community profiles associated with young and old CF patients with a particular focus on the differences between respective “early” and “late” colonizing organisms. Finally we assess the influence of Cystic Fibrosis Transmembrane Regulator (CFTR) mutation on bacterial abundance and identify genotype-specific communities involving members of the Pseudomonadaceae, Xanthomonadaceae, Moraxellaceae and Enterobacteriaceae amongst others. Data presented here provides insights into the CF airway microbiota, including initial diversification events in younger patients and establishment of specialized communities of pathogens associated with poor pulmonary function in older patient populations.

Smoking tobacco and heavy alcohol use are associated with an increased risk of oral cancer, and at least 1 report has identified both smoking and drinking as risk factors for oral epithelial dysplasia (OED), a histopathologic diagnosis associated with an increased risk of oral cancer.1–5 Nevertheless, although a growing body of literature has explored the occurrence and correlates of depressive symptoms among head and neck cancer patients,6–12 and although depression has been linked to both alcohol abuse and smoking in a variety of diverse populations,10,13–25 only limited information is available on the relationship between depression and either smoking or drinking among persons diagnosed with oral cancer or precancer.10 As part of a larger retrospective investigation focusing on risk factors for oral cancer and OED,26 we obtained information on depressive symptoms at the time the study interview was administered.6 In a previous report, we identified young age (

The type III secretion system of Pseudomonas aeruginosa, responsible for acute infection, is composed of over twenty proteins that facilitate cytotoxin injection directly into host cells. Integral to this process is production and secretion of PcrV. Administration of a recently developed, anti-PcrV immunoglobulin, either as a therapeutic or prophylactic has previously demonstrated efficacy against laboratory strains of P. aeruginosa in a murine model. To determine if this therapy is universally applicable to a variety of P. aeruginosa clinical isolates, genetic heterogeneity of pcrV was analyzed among strains collected from three geographically distinct regions; United States, France and Japan. Sequence analysis of PcrV demonstrated limited variation among the clinical isolates examined. Strains were grouped according to the presence of non-synonymous single nucleotide polymorphisms. Representative isolates from each mutant group were examined for the ability of anti-PcrV to bind the protein secreted by these strains. The protective effect of anti-PcrV IgG against each strain was determined using an epithelial cell line cytotoxicity assay. The majority of strains tested demonstrated reduced cytotoxicity in the presence of anti-PcrV IgG. This study provides insights into the natural sequence variability of PcrV and an initial indication of the amino acid residues that appear to be conserved across strains. It also demonstrates the protective effect of anti-PcrV immunotherapy against a multitude of P. aeruginosa strains from diverse global regions with a variety of mutations in PcrV.

Two liquefaction cycles for LNG (liquefied natural gas) production are compared in this paper. One is a well known MR (mixed refrigerant) JT cycle with two phase separators and four heat exchangers. Another one is the novel concept of hybrid cycle, which is to replace the last stage JT expansion with a turbine expander. The inlet flow to the turbine expander is deliberately warmed up by NG (natural gas) stream to guarantee superheated vapor phase and increase useful work. The turbine expander is to extract pressure exergy and reduce entropy generation by producing work and alleviating work requirement in the compressor. This paper describes the detailed processes of hybrid JT‐expander cycle and the quantitative comparison results by HYSYS simulation under some realistic physical constraints.

The growth behavior of the nitride layer inside a long hollow tube with an intricate geometry was studied to find a way to enhance the uniformity of the nitride layer. The inner surface of steel tube of 30- mm inner diameter was machined to have corrugation depths ranging from 0.65 to 3.90 mm and corrugation widths from 1.10 to 13.2 mm. After the specimens were ion nitrided at 525 ° for 10 hr in 2.5 torr operating pressure, the thickness of the compound layer and the diffusion layer on the land and the groove was measured and analyzed according to corrugation depth and width. As the corrugation becomes deeper, the thickness of the compound layer on the land increases and that of the layer on the groove decreases. The thickness of the diffusion layer on the land and the groove depicts a similar tendency to that of the compound layer. As the corrugation becomes wider, the compound layer thickness on the land decreases and that of the layer on the groove increases to the contrary. Thickness variations in the diffusion layer on the land and the groove resemble those of the compound layer. The nitride growth characteristics on the corrugated geometry in ion nitriding was discussed in view of Hollow Cathode Discharge (HCD) effect, nitrogen concentration, and the probability of compound adsorption.

Glycosylated, membrane-associated E1 (58-kDa) and E2 (47- to 49-kDa) rubella virus proteins and unglycosylated nucleoprotein C (33 kDa), from separately expressed vaccinia virus recombinants, were injected into golden Syrian hamsters. Rubella virus E1 and E2 glycoproteins consistently induced an organ-specific autoimmune disease, autoimmune lymphocytic hypophysitis, which was evidenced by the induction of autoantibodies against pituitary cells and by lymphocytic infiltration of the pituitary. Neonatal thymectomy prevented the disease. In contrast, rubella virus nucleoprotein C did not induce either autoantibodies against pituitary cells or lymphocytic infiltration of the pituitary. This finding raises the possibility that virus-specific protein itself can induce an organ-specific autoimmune disease in certain circumstances.

Aim To determine changes in small nerve fibres in gastric mucosa in patients with Type 2 diabetes by morphological observation. Methods In twenty-five non-diabetic and 21 Type 2 diabetic participants, gastric mucosal biopsy under endoscopy was performed. Innervation in gastric mucosa was detected using immunohistochemical staining. Anti-protein gene product (PGP) 9.5 positive nerves underwent morphological observation and quantitative analysis. Results Small nerve fibres in gastric mucosa were shortened in the diabetic subjects. The ratio of gastric mucosal protrusions maintaining nerve fibres between gastric pits to total observed protrusions was lower in patients with Type 2 diabetes compared with the non-diabetic subjects (ratio of innervated protrusion/total protrusion: 0.49 ± 0.12 vs. 0.89 ± 0.06, P

A single administration of complete Freund's adjuvant (CFA), type 1 carrageenan (Car), or silica 7, 2, and 2 days, respectively, before infection with a low dose (1 × 102 plaque-forming units/mouse) of encephalomyocarditis D (EMC-D) virus resulted in a significant increase in the incidence of diabetes in SJL/J mice (100%) compared with untreated EMC-D virus–infected mice (40%). Peritoneal macrophages were isolated from uninfected SJL/J mice, which had been treated once with silica, and transferred into SJL/J mice 2 days before low-dose EMC-D infection. Approximately 90% of the mice became diabetic, whereas 30% of mice that received virus alone became diabetic. The depletion of macrophages by treatment with the combined anti-Mac-1 and anti-Mac-2 monoclonal antibodies after a single administration of CFA, Car, or silica resulted in almost complete prevention of β-cell destruction in EMC-D virus–infected mice. Furthermore, none of the mice in which macrophages were depleted by long-term treatment with silica and 10% of the mice treated with Car before virus infection became diabetic. On the basis of these observations, we conclude that macrophages are directly involved in the destruction of β-cells, leading to the development of clinical diabetes in EMC-D virus–infected mice.