bluuebunny/crossref_metadata_2025 huggingface dataset:
Eating disorders mental health literacy in Singapore: beliefs of young adult women concerning treatment and outcome of bulimia nervosa
Authors: Chen Anna , Mond Jonathan M. , Kumar Rajeev
Published: January 2010

Aim: We examined the eating disorders ‘mental health literacy’ of young adult women in Singapore.

Methods: A self‐report questionnaire was completed by 255 women recruited from three university campuses. A vignette of a fictional (female) person exhibiting the characteristic features of bulimia nervosa was presented, followed by a series of questions concerning the treatment and outcome of the problem described. A measure of eating disorder symptoms was included in the questionnaire.

Results: Consulting a primary care practitioner, counsellor or psychologist; seeking the advice of a (female) family member or friend; getting advice about diet and nutrition; and taking vitamins and minerals were the interventions most often considered helpful. Participants were less positive about the benefits of psychiatristsand were ambivalent about the use of psychotropic medication. Participants' mothers were most often considered helpful as they are an initial source of help. Among participants with a high level of eating disorder symptoms, recognition of an eating problem was poor. A minority of participants believed that treatment would result in full recovery.

Conclusions: Aspects of the eating disorders mental health literacy of young Singaporean women may be conducive to low or inappropriate treatment seeking. Health promotion programmes need to target not only at‐risk individuals, but also their family members and social circle.
Is a national framework for implementing early psychosis services necessary? Results of a survey of Australian mental health service directors
Authors: Catts Stanley V. , Evans Russell W. , O'Toole Brian I. , Carr Vaughan J. , Lewin Terry , Neil Amanda L. , Harris Meredith G. , Frost Aaron D.J. , Crissman Belinda R. , Eadie Kathy
Published: January 2010

Aim: Expert opinion holds that the rate of implementation of specialist services for first presentation psychosis in Australia is much too slow. We aimed to collect evidence regarding this view from the first national survey of adult public mental health services about their self‐reported efforts to implement specialist early psychosis intervention (EPI).

Methods: Using a purpose‐designed Census form for assessing EPI implementation, adult public mental health service directors throughout Australia were asked about EPI‐relevant local service activities.

Results: Sixty Census forms were returned (response rate = 61%), representing a total catchment population of 12.5 million people. A minority of services reported high levels of EPI implementation, which varied widely between area services and across state and territory jurisdictions. Rural and remote services were overrepresented in the lowest levels of reported EPI implementation. Only one service characteristic, the value of identifiable funding committed specifically to EPI, was predictive of level of reported EPI implementation.

Conclusions: The disturbingly high levels of variability in EPI implementation across jurisdictions suggest a pressing need for a set of nationally agreed uniform EPI implementation standards. Additional specific strategies for rural and remote mental health services may be needed for these services to implement EPI.
Negative relationships between cellular immune response, Mhc class II heterozygosity and secondary sexual trait in the montane water vole
Authors: Charbonnel Nathalie , Bryja Josef , Galan Maxime , Deter Julie , Tollenaere Charlotte , Chaval Yannick , Morand Serge , Cosson Jean‐François
Published: January 2010

Heterogeneities in immune responsiveness may affect key epidemiological parameters and the dynamics of pathogens. The roles of immunogenetics in these variations remain poorly explored. We analysed the influence of Major histocompatibility complex (Mhc) genes and epigamic traits on the response to phytohaemagglutinin in males from cyclic populations of the montane water vole (Arvicola scherman). Besides, we tested the relevance of lateral scent glands as honest signals of male quality. Our results did not corroborate neither the hypotheses of genome‐wide heterozygosity‐fitness correlation nor the Mhc heterozygote advantage. We found a negative relationship between Mhc hetetozygosity and response to phytohaemagglutinin, mediated by a specific Mhc homozygous genotype. Our results therefore support the hypothesis of the Arte‐Dqa‐05 homozygous genotype being a ‘good’ Mhc variant in terms of immunogenetic quality. The development of the scent glands seems to be an honest signal for mate choice as it is negatively correlated with helminth load. The ‘good gene’ hypothesis was not validated as Arte‐Dqa‐05 homozygous males did not exhibit larger glands. Besides, the negative relationship observed between the size of these glands and the response to phytohaemagglutinin, mainly for Mhc homozygotes, corroborates the immunocompetence handicap hypothesis. The Mhc variants associated with larger glands remain yet to be determined.
ORIGINAL ARTICLE: Allee effects, adaptive evolution, and invasion success
Authors: Kanarek Andrew R. , Webb Colleen T.
Published: January 2010

The mechanisms that facilitate success of an invasive species include both ecological and evolutionary processes. Investigating the evolutionary dynamics of founder populations can enhance our understanding of patterns of invasiveness and provide insight into management strategies for controlling further establishment of introduced populations. Our aim is to analyze the evolutionary consequences of ecological processes (i.e., propagule pressure and threshold density effects) that impact successful colonization. We address our questions using a spatially‐explicit modeling approach that incorporates dispersal, density dependent population growth, and selection. Our results show that adaptive evolution may occur in small or sparse populations, providing a means of mitigating or avoiding inverse density dependent effects (i.e., Allee effects). The rate at which this adaptation occurs is proportional to the amount of genetic variance and is a crucial component in assessing whether natural selection can rescue a population from extinction. We provide theoretical evidence for the importance of recognizing evolution in predicting and explaining successful biological invasions.
Microendoscopic discectomy for recurrent lumbar disc herniation*
Authors: Matsumoto M , Ishii K , Watanabe K , Tsuji T , Nakamura M , Toyama Y , Chiba K
Published: January 2010

Introduction: The purpose of this study is to elucidate the feasibility of microendoscopic discectomy (MED) for the treatment of recurrent lumbar disc herniation.

Methods: Thirty‐six patients with recurrent lumbar disc herniation were treated using MED (30 men and six women; mean age: 45.7 years, range: 26–80 years; mean follow‐up: 24.4 months, range: 12–52 months; mean duration between the primary and revision surgery: 65.9 months, range: 1–320 months) (recurrent group). Sex‐ and age‐matched patients with primary lumbar disc herniation treated by MED served as the control group (primary group). The clinical outcomes were evaluated using the Japanese Orthopaedic Association score for low back pain and questionnaires regarding MED.

Results: The average Japanese Orthopaedic Association scores before surgery and at the final follow‐up were significantly lower in the recurrent group than in the primary group (10.8 ± 3.4 versus 15.0 ± 4.0 before surgery, P=0.001 and 25.4 ± 2.6 versus 26.8 ± 1.9 at follow‐up, P=0.013), while the average recovery rates were not significantly different between the two groups (80.3 ± 14.1% versus 84.5 ± 14.6, P=0.22). The surgical time was significantly longer for the recurrent group than for the primary group (83.0 ± 41.8 min versus 67.1 ± 18.1 min,P=0.042). Of the 18 questionnaire respondents, 17 answered that postoperative pain was milder after MED than after a standard discectomy.

Conclusion: MED is a feasible surgical option for recurrent lumbar disc herniation, yielding surgical outcomes comparable to those obtained in primary lumbar disc herniation.
Controversial Role of GPOs in Healthcare‐Product Supply Chains
Authors: Hu Qiaohai (Joice) , Schwarz Leroy B.
Published: January 2010

This paper examines the controversial role that Group Purchasing Organizations (GPOs) play in the supply chains for healthcare products. Among the controversies, perhaps the most fundamental one is whether or not GPOs reduce purchasing costs for their members. However, the fiercest controversy is around the “contract administration fees (CAFs)” that GPOs charge to manufacturers. We examine these and other controversies using a Hotelling duopoly model. Among our conclusions: GPOs increase competition between manufacturers and lower prices for healthcare providers. However, GPOs reduce manufacturers' incentives to introduce innovations to existing products. We also demonstrate that the existence of lower off‐contract prices is not, per se, evidence of anticompetitive behavior on the part of GPOs. Indeed, we demonstrate that, under certain circumstances, the presence of a GPO lowers off‐contract prices. We also examine the consequences of eliminating the “safe harbor” provisions that permit healthcare GPOs to charge CAFs to manufacturers, and conclude that it would not affect any party's profits or costs.
In Situ Fuel Cell Water Metrology at the NIST Neutron Imaging Facility
Authors: Hussey D. S. , Jacobson D. L. , Arif M. , Coakley K. J. , Vecchia D. F.
Published: January 2010

Neutron imaging has been demonstrated to be a powerful tool to measure the in situ water content of commercial proton exchange membrane fuel cells (PEMFCs) in two and three dimensions. The National Institute of Standards and Technology neutron imaging facility was designed to produce a high intensity, highly collimated neutron imaging beam to measure the water content of operating fuel cells. The details of the neutron optics and neutron detection are discussed in terms of the random uncertainty in measuring the liquid water thickness that is typical of operating PEMFCs.
Water Management Issues for Direct Borohydride/Peroxide Fuel Cells
Authors: Lux Scott , Gu Lifeng , Kopec Grant , Bernas Robert , Miley George
Published: January 2010

This study evaluated water management strategies to lengthen the run time of a batch fueled direct sodium borohydride/peroxide (NaBH4/H2O2) proton exchange membrane fuel cell. The term “batch fueled” refers specifically to a fuel tank containing a fixed volume of fuels for use in the run. The length of a run using a fixed fuel tank is strongly influenced by water dynamics. The water that reacts at the anode is produced at the cathode, and is transported through the membrane via drag and diffusion. Resulting concentration changes in the fuel of the NaBH4/H2O2 fuel cell were modeled to evaluate the run lifetime. The run time is defined as the amount of time required for NaBH4 or for NaBO2 (the byproduct compound) to reach either solubility limit or until the fuel is depleted, whichever occurs first. As part of the evaluation, an “effective” H2O drag coefficient (net drag minus back diffusion) with Nafion® 112 was experimentally determined to be 1.14 and 4.36 at 25°C and 60°C, respectively. The concentrations of the NaBH4 and NaBO2 solutions were calculated as a function of initial concentration, and for the case where H2O was supplied to the anode compartment during operation. Several strategies to increase the run time by both passive and active water management were considered. It is found that the run time is increased from 10 W h to 57 W h, with a decrease in the initial NaBH4 concentration from 30 wt % (typically employed in these cells) to 10 wt %. Adding 0.125 ml/min H2O to the bulk anode solution increases the run time of a 10 wt % NaBH4 solution by a factor of 1.6. Adding 0.225 ml/min H2O to 30 wt % NaBH4 bulk solution increases the run time by a factor of 4.4. While attractive for increasing run time, the practicality of water addition depends on its availability or requires incorporation of an added unit, designed to separate and recirculate water from the cathode solution.
Solid Oxide Fuel Based Auxiliary Power Unit for Regional Jets: Design and Mission Simulation With Different Cell Geometries
Authors: Santarelli M. , Cabrera M. , Calì M.
Published: January 2010

Although it accounts for only 4.2% of the total global warming potential, the concern today is that aviation generated CO2 is projected to grow to approximately 5.7% by 2050. Aviation emissions are growing faster than any other sector and they risk undermining the progress achieved through emission cuts in other areas of the economy. Rapidly emerging hydrogen and fuel-cell-based technologies could be developed for future replacement of on-board electrical systems in “more-electric” or “all-electric” aircrafts. Primary advantages of deploying these technologies are low emissions and low noise (important features for commuter airplanes, which takeoff and land in urban areas). Solid oxide fuel-cell (SOFC) systems could result advantageous for some aeronautical applications due to their capability of accepting hydrocarbons and high energy-density fuels. Moreover they are suitable for operating in combined-heat-and-power configurations, recovering heat from the high-temperature exhaust gases, which could be used to supply thermal loads therefore reducing the electric power requested by the aircraft. ENFICA-FC is a project selected by the European Commission in the Aeronautics and Space priority of the Sixth Framework Programme (FP6) and led by Politecnico di Torino, in Turin, Italy. One of the objectives of the project is to carry out a feasibility study on a more-electric intercity aircraft (regional jet: 32 seats). After the characterization of the power consumption of electrical and nonelectrical loads, and the definition of a mission profile, the design of the SOFC-based energy system as well as the simulation of a complete mission is performed hypothesizing different system configurations. The simulation concerns both the stack (current and current density, cell and stack voltage, etc.) and the balance-of-plant (air compressor power, gross stack power, system efficiency, etc.). The obtained results are analyzed and discussed.
Thin Film Solid Oxide Fuel Cells Deposited by Spray Pyrolysis
Authors: Xie Yongsong , Neagu Roberto , Hsu Ching-Shiung , Zhang Xinge , Decès-Petit Cyrille , Qu Wei , Hui Rob , Yick Sing , Robertson Mark , Maric Radenka , Ghosh Dave
Published: January 2010

Two techniques of spray pyrolysis, namely, electrostatic and pneumatic spray deposition, were used to deposit samaria-doped ceria (SDC) electrolyte and lanthanum strontium cobalt ferrite (LSCF) cathode on cermet or metal supported anodes for solid oxide fuel cells (SOFCs) operated at reduced temperature. The deposition processes, the properties of the deposited films, and the electrochemical performances of the fabricated cells are reported in this paper. The deposited SDC electrolytes were dense and gas-tight, and had good adhesion to the underlying anodes. The deposited LSCF cathode had a preferred morphology to facilitate the transport of oxygen gas and effective contact with the electrolyte. Button cell testing indicated that the SOFCs with electrolyte or cathode deposited by spray pyrolysis had good electrochemical performance. This study demonstrated that spray pyrolysis is a cost-effective process for fabricating thin film SOFCs, especially metal supported SOFCs.
Performance Study of Nickel Covered by Lithium Cobaltite Cathode for Molten Carbonate Fuel Cells: A Comparison in Li/K and Li/Na Carbonate Melts
Authors: Paoletti C. , Zaza F. , Carewska M. , Lo Presti R. , Simonetti E.
Published: January 2010

The slow dissolution of the lithiated NiO cathode represents one of the main causes of performance degradation in molten carbonate fuel cells. Two main approaches are usually investigated to overcome this problem: modifying the electrolyte composition and studying innovative cathode. In this work, the production of an alternative material as well as a study in different carbonate melt mixtures (62/38 mol % Li/K and 52/48 mol % Li/Na) of this innovative cathode have been taken into account. The issue of cathode surface protection was attained covering a nickel substrate with a thin layer of lithium cobaltite doped with magnesium (LiMg0.05Co0.95O2); a sol impregnation technique was used to deposit gel precursors on the porous surface of the substrate. Chemical analysis, electrical conductivity measurements and scanning electron microscopy were used to characterize the cathodes before and after in-cell tests. The cathodic performance was tested in two 3 cm2 area cells assembled with the following electrolyte compositions: Li/K=62/38 mol % and Li/Na=52/48 mol % in order to investigate the cathode behavior in different carbonate melt environments. Polarization curves and electrochemical impedance spectroscopy measurements were carried out during cell lifetime (about 850 h). Finally, different compositions of the cathodic gas were used to study the influence of oxygen and carbon dioxide on the electrode kinetics.
Influence of Sulfonationity of Epoxy-Based Semi-Interpenetrating Polymer Networks of Sulfonated Polyimides as Proton Exchange Membranes on the Performance of Fuel Cell Application
Authors: Wang Yen-Zen , Ho Ko-Shan , Wu Shinn-Dar , Hsieh Kuo-Huang , Lee Chi-Hung
Published: January 2010

A novel epoxy-based semi-interpenetrating polymer networks membrane (SPIX-EP40) as the proton exchange membrane was prepared by a flexible epoxy network with sulfonated polyimide. A series of sulfonated polyamic acid (SPAA) were prepared from 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,2-benzidinedisulfonic acid (BDSA) and nonsulfonated diamines, such as 4,4′-diaminodiphenyl sulfone. Solid-state C13 nuclear magnetic resonance spectra and Fourier transform infrared spectroscopy were used to verify the synchronization of the imidization of SPAA and the crosslinking reactions of epoxy. The sulfonationity of the copolymers was regulated through a variation in the molar ratio of BDSA to diamine. These membranes owned a good thermal stability and exhibited high proton conductivity that was measured as a function of temperature. The resulting SPI0.7-EP40 and SPI0.8-EP40, at 100% relative humidity, displayed proton conductivities higher than those of Nafion® 117. The membranes displayed higher conductivities than Nafion® membranes because of owning higher activational energies and higher ion exchange capacities. An isotropic swelling phenomenon in water was found for the membrane. From the results of water uptake and the microstructure analyses using transmission electron microscopy (TEM) on different sulfonated levels, it was found that the number of water clusters in SPIX-EP40 membranes increased as the increasing water uptake and the size of water cluster were changed with the sulfonation levels. TEM confirmed the widespread and well-connected hydrophilic domains, demonstrating the presence of the favorable proton-transporting performances of the SPIX-EP40 membrane.
Simulation Study for the Optimization of Microtubular Solid Oxide Fuel Cell Bundles
Authors: Funahashi Yoshihiro , Shimamori Toru , Suzuki Toshio , Fujishiro Yoshinobu , Awano Masanobu
Published: January 2010

Microtubular solid oxide fuel cells (SOFCs) are shown to be robust under rapid temperature changes and have large electrode area per volume (high volumetric power density). Such features are believed to increase a variety of application. Our study aims to establish a fabrication technique for microtubular SOFC bundles with the volumetric power density of 2 W cm−3 at 0.7 V. So far, we have succeeded to develop a fabrication technology for microtubular SOFC bundles using anode supported tubular SOFCs and cathode matrices with well-controlled microstructures. A key to improve the performance of the microtubular SOFC bundles is to optimize the microstructure of the cathode matrices because it influences a pressure loss for air and electric current collection. In this paper, a simulation study of an air flow, temperature, and potential distributions in the microtubular SOFC bundle was conducted in order to understand the characteristics of the present bundle design. In addition, operating conditions of the microtubular SOFC bundles was discussed for realizing the target power density of 2 W cm−3.
Correlating Nitrogen Accumulation With Temporal Fuel Cell Performance
Authors: Müller Eric A. , Kolb Florian , Guzzella Lino , Stefanopoulou Anna G. , McKay Denise A.
Published: January 2010

The permeability or crossover characteristics of a typical perfluorosulfonic acid base type membrane are used for the temporal and spatial estimations of nitrogen concentration along the anode channels of a polymer electrolyte membrane fuel cell stack. The predicted nitrogen accumulation is then used to estimate the impact of local fuel starvation on stack voltage through the notion of apparent current density. Despite the simplifying assumptions on the water accumulation and membrane hydration levels, the calibrated model predicts reasonably well the response of a 20-cell stack with a dead-ended anode. Specifically, the predicted voltage decay and the estimated gas composition at the anode outlet are experimentally validated using the stack-averaged voltage and a mass spectrometer. This work shows that the crossover of nitrogen and its accumulation in the anode can cause a considerable decay in stack voltage and should be taken into account under high hydrogen utilization conditions.
Numerical Analysis of Water Transport Through the Membrane Electrolyte Assembly of a Polymer Exchange Membrane Fuel Cell
Authors: Zhang Xu , Song Datong , Wang Qianpu , Huang Cheng , Liu Zhong-Sheng , Shah A. A.
Published: January 2010

The effects of water transport through membrane electrolyte assembly of a polymer exchange membrane fuel cell on cell performance has been studied by a one-dimensional, nonisothermal, steady-state model. Three forms of water are considered in the model: dissolved water in the electrolyte or membrane, and liquid water and water vapor in the void space. Phase changes among these three forms of water are included based on the corresponding local equilibriums between the two involved forms. Water transport and its effect on cell performance have been discussed under different operating conditions by using the value and the sign of the net water transport coefficient, which is defined by the net flux of water transported from the anode side to the cathode side per proton flux. Optimal cell performance can be obtained by adjusting the liquid water saturation at the interface of the cathode gas diffusion layer and flow channels.
Cost-Effective Single Step Cofiring Process for Manufacturing Solid Oxide Fuel Cells Using HSC™ Anode
Authors: Yoon Kyung Joong , Ye Guosheng , Gopalan Srikanth , Pal Uday B.
Published: January 2010

The anode-supported planar solid oxide fuel cell (SOFC) was fabricated by a cost-effective single step cofiring process using high shear compaction (HSC)™ anode substrate. The HSC™ process is a novel ceramic tape fabrication technique, which offers advantages in low-cost and high-volume production of the anode substrates over the conventional tape forming processes. The cell was comprised of a porous HSC™ Ni+8 mol % yttria-stabilized zirconia (YSZ) anode substrate, a porous Ni+YSZ anode barrier layer, a porous and fine-grained Ni+YSZ anode active layer, a dense YSZ electrolyte, a porous and fine-grained Ca-doped LaMnO3(LCM)+YSZ composite cathode active layer, and a porous LCM cathode current collector layer. The fabrication process involved wet powder spraying of the anode barrier layer over the HSC™ anode substrate followed by screen-printing of the remaining component layers. The cell was then cofired at 1340°C for 2 h. The microstructure and the open circuit voltage of the cell confirmed that the cell was crack-free and leak-tight. The cofired cell showed a stable and acceptable electrochemical performance at 800°C under humidified hydrogen (3–60% H2O) as fuel and air as oxidant. The anode active layer with finer and less porous microstructure increased the triple phase boundary length and improved cell performance under conditions that simulated higher fuel utilization. The material system and fabrication process presented in this work offers great advantage in low-cost and high-volume production of SOFCs, and it can be the basis for scale-up and successful commercialization of the SOFC technology.
Durability Test Results of a Polymer Electrolyte Membrane Fuel Cell Operated at Overnominal Temperature With Low Humidified Reactants
Authors: Wasterlain Sébastien , Candusso Denis , Harel Fabien , François Xavier , Péra Marie-Cécile , Hissel Daniel
Published: January 2010

A three-cell polymer electrolyte membrane fuel cell stack equipped with perfluorinated ionomer membranes is tested for 1000 h in severe operating conditions. The fuel cell (FC) is fed by dry hydrogen/low humidified air and it is simultaneously operated at overnominal temperature. During the long term experiment, some polarization curves and electrochemical impedance spectra are recorded at regular time-spaced intervals for various stoichiometry rates. The objective is to characterize the degradation of FC performances with the aim to better understand the FC aging mechanisms. Some response surfaces are plotted to display and analyze the stack voltage variations as a function of aging time, static load current, and gas utilization rates. Different points of the FC impedance spectra are also considered. The evolutions of their coordinates in the Nyquist plot can be monitored versus aging time and for different gas utilization rates.
Effect of Bridging Groups on Sulfonated Poly(imide-Siloxane) for Application in Proton Exchange Membrane
Authors: Lee Chi-Hung , Chen Jia-Ru , Shiu Hung-Wei , Ho Ko-Shan , Wu Shinn-Dar , Hsieh Kuo-Huang , Wang Yen-Zen
Published: January 2010

A series of six-membered sulfonated poly(imide-siloxane)s (SPIs) was synthesized using 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), aminopropyl-terminated polydimethylsiloxane (PDMS) 2,2-benzidinedisulfonic acid (BDSA), as the sulfonation target diamine groups, and various nonsulfonated diamine monomers behaving as bridging groups. The structure-property relationship of SPI-SXx membranes is discussed in detail according to the chemical structure of the various nonsulfonated diamines of the SPI-SXx membranes from the viewpoints of proton conductivity, ion exchange capacity (IEC), and membrane properties (water uptake and membrane swelling) at equal PDMS content SPI-SXx. The PDMS was introduced to enhance the proton conductivity and water uptake attributed from the high flexibility of the siloxane segments. The conductivity and water uptake of angled SPI-SXm and oxydianiline-based SPI-SX membranes (SPI-SXO) are greater than those prepared from diaminodiphenylmethane-based SPI-SX membranes (SPI-SXD) at a given IEC. These differences resulted from the increased number of entanglements of the SPI-SXx membrane. The SPI-SXD showed almost isotropically dimensional changes with the increase in water uptake, and the volume were slightly smaller than those estimated from the additivity rule. Free volume in the SPI-SXx increased with the increase in bulky irregular packing in nonsulfonated segments, which augmented the water uptake and, in turn, the conductivity of the polymer. With the increase in temperature, conductivity increased more rapidly in SPI-SXx than in Nafion 117. Microscopic analyses revealed that these smaller (<10 nm) and well-dispersed hydrophilic domains contribute to better proton conducting properties. The new sulfonated poly(imide-siloxane)s have proved to be a possible candidate as the polymer electrolyte membrane for polymer electrolyte fuel cells (PEFCs) and direct methanol fuel cells (DMFCs).
Exploring Transient Behavior at Startup of a Polymer Electrolyte Membrane Fuel Cell
Authors: Mishra Bikash , Wu Junxiao
Published: January 2010

A two phase nonisothermal 3D unsteady model is used to study the transients at start-up of a polymer electrolyte membrane fuel cell. The model is used to simulate start-up under different starting or initial conditions. The objective is to study the transient behavior of current and the phenomena affecting it. The transient current density obtained from simulation under purged and inflow/equilibrium initial conditions are plotted. The saturation and the temperature profile evolution within the gas diffusion layer under different conditions are also studied. The effect of gas diffusion layer thickness and reaction rate on the current density evolution is analyzed. It is found that the transient current density depends on the initial condition. Mass transport is the major phenomenon influencing the current density profile, and the mass transport transients are found to be subsecond in nature. The consumption and transport time scales are seen to affect the current undershoot at high loads. The liquid water evolution and distribution behaves very differently, under different initial conditions, as well as different inflow conditions. However, the total time taken by liquid water and temperature to reach steady state for different initial conditions is very close. It is also seen that the temperature transient is less than the liquid water transient, overall.
THE CLIFFORD SPACE GEOMETRY OF CONFORMAL GRAVITY AND U(4) × U(4) YANG–MILLS UNIFICATION
Authors: CASTRO CARLOS
Published: January 2010

It is shown how a conformal gravity and U (4) × U (4) Yang–Mills grand unification model in four dimensions can be attained from a Clifford gauge field theory in C-spaces (Clifford spaces) based on the (complex) Clifford Cl (4, C) algebra underlying a complexified four-dimensional space–time (eight real dimensions). Upon taking a real slice, and after symmetry breaking, it leads to ordinary gravity and the Standard Model in four real dimensions. A brief conclusion about the noncommutative star-product deformations of this Grand Unified Theory of gravity with the other forces of Nature is presented.
CONFORMAL ANOMALY IN NON-HERMITIAN QUANTUM MECHANICS
Authors: GIRI PULAK RANJAN
Published: January 2010

A model of an electron and a Dirac monopole interacting in an axially symmetric non-Hermitian but [Formula: see text]-symmetric potential is discussed in detail. The intriguing localization of the wave-packet is observed as a result of the anomalous breaking of the scale symmetry. The symmetry algebra for the system, which is the conformal algebra SO(2, 1), is discussed as a subalgebra of the enveloping algebra of an algebra, composed of the Virasoro algebra, {Ln, n ∈ ℕ} and an Abelian algebra, {Pn, n ∈ ℕ}.
FIRST-CLASS APPROACHES TO MASSIVE 2-FORMS
Authors: CIOROIANU EUGEN-MIHĂIŢĂ , SĂRARU SILVIU CONSTANTIN , BĂLUŞ OANA
Published: January 2010

Massive 2-forms are analyzed from the point of view of the Hamiltonian quantization using the gauge-unfixing approach and respectively the Batalin–Fradkin method. Both methods finally output the manifestly Lorentz covariant path integral for 1- and 2-forms with Stückelberg coupling.
ASYMPTOTIC ANALYSIS AND NUMERICAL MODELING OF MASS TRANSPORT IN TUBULAR STRUCTURES
Authors: CARDONE GIUSEPPE , PANASENKO GRIGORY P. , SIRAKOV YVAN
Published: January 2010

In this paper the flow in a thin tubular structure is considered. The velocity of the flow stands for a coefficient in the convection-diffusion equation set in the thin structure. An asymptotic expansion of solution is constructed. This expansion is used further for justification of an asymptotic domain decomposition strategy essentially reducing the memory and the time of the code. A numerical solution obtained by this strategy is compared to the numerical solution obtained by a direct FEM computation.
DOUBLE POROSITY MODELS FOR LIQUID FILTRATION IN INCOMPRESSIBLE POROELASTIC MEDIA
Authors: MEIRMANOV ANVARBEK
Published: January 2010

Double porosity models for the liquid filtration in a naturally fractured reservoir is derived from the homogenization theory. The governing equations on the microscopic level consist of the stationary Stokes system for an incompressible viscous fluid, occupying a crack-pore space (liquid domain), and stationary Lame equations for an incompressible elastic solid skeleton, coupled with the corresponding boundary conditions on the common boundary "solid skeleton-liquid domain". We assume that the liquid domain is a union of two independent systems of cracks (fissures) and pores, and that the dimensionless size δ of pores depends on the dimensionless size ε of cracks: δ = εr with r > 1. The rigorous justification is fulfilled for homogenization procedure as the dimensionless size of the cracks tends to zero, while the solid body is geometrically periodic. As the result we derive the well-known Biot–Terzaghi system of liquid filtration in poroelastic media, which consists of the usual Darcy law for the liquid in cracks coupled with anisotropic Lame's equation for the common displacements in the solid skeleton and in the liquid in pores and a continuity equation for the velocity of a mixture. The proofs are based on the method of reiterated homogenization, suggested by Allaire and Briane. As a consequence of the main result we derive the double porosity model for the filtration of the incompressible liquid in an absolutely rigid body.
A SIMPLE METHOD FOR PREDICTION OF THE REDUCED SCATTERING COEFFICIENT IN TISSUE-SIMULATING PHANTOMS
Authors: FU JIANWEI , QUAN GUOTAO , GONG HUI
Published: January 2010

This paper proposes a method for predicting the reduced scattering coefficients of tissue-simulating phantoms or the desired amount of scatters for producing phantoms according to Mie scattering theory without measurements with other instruments. The concentration of the scatters TiO 2 particles is determined according to Mie theory calculation and added to transparent host epoxy resin to produce phantoms with different reduced scattering coefficients. Black India Ink is added to alter the absorption coefficients of the phantoms. The reduced scattering coefficients of phantoms are measured with single integrating sphere system. The results show that the measurements are in direct proportion to the concentration of TiO 2 and have identical with Mie theory calculation at multiple wavelengths. The method proposed can accurately determine the concentration of scatters in the phantoms to ensure the phantoms are qualified with desired reduced scattering coefficients at specified wavelength. This investigation should be possible to manufacture the phantom simply in reasonably accurate for evaluation of biomedical optical imaging systems.
SIMULATION AND MEASUREMENT OF FLOW FIELD IN MICROCHIP
Authors: WANG CHUAN , DING ZHIHUA , MENG JIE , YIN BINGLUN
Published: January 2010

Cancer (malignant tumor) is one of the serious threats to human life, causing 13% of all human deaths. A crucial step in the metastasis cascade of cancer is hematogenous spreading of tumor cells from a primary tumor. Thus, isolation and identification of cells that have detached from the primary tumor and circulating in the bloodstream (circulating tumor cells, CTCs) is considered to be a potential alternation to detect, characterize, and monitor cancer. Current methods for isolating CTCs are limited to complex analytic approaches that generate very low yield and purity. Here, we propose a high throughput 3D structured microfluidic chip integrated with surface plasmon resonance (SPR) sensor to isolate and identify CTCs from peripheral whole blood sample. The microfluidic velocity-field within the channel of the chip is mediated by an array of microposts protruding from upper surface of the channel. The height of microposts is shorter than that of the channel, forming a gap between the microposts and the lower surface of the channel. The lower surface of the channel also acts as the SPR sensor which can be used to identify isolated CTCs. Microfluidic velocity-field under different parameters of the arrayed microposts is studied through numerical simulation based on finite element method. Measurement on one of such fabricated microchips is conducted by our established optical Doppler tomography technique benefiting from its noninvasive, noncontact, and high-resolution spatial-resolved capabilities. Both simulation and measurement of the microfluidic velocity-field within the structured channel demonstrates that it is feasible to introduce fluidic mixing and causes perpendicular flow component to the lower surface of the channel by the 3D structured microposts. Such mixing and approaching capabilities are especially desirable for isolation and identification of CTCs at the coated SPR sensor.
DETECTING CEREBRAL ARTERIES AND VEINS: FROM LARGE TO SMALL
Authors: MIAO PENG , LI MINHENG , LI NAN , REGE ABHISHEK , ZHU YISHENG , THAKOR NITISH , TONG SHANBAO
Published: January 2010

In this paper, a model-based reconstruction technique is proposed to simultaneously measure the relative deoxyhemoglobin concentration and the relative blood flow velocity in cerebral cortex. With the help of this model-based reconstruction technique, artifacts due to nonuniform laser illumination and curvature of cortex are efficiently corrected. The results of relative deoxy-hemoglobin concentration and relative blood flow velocity are then used to detect and distinguish cerebral arteries and veins. In an experimental study on rat, cerebral blood vessels are segmented from the reconstructed blood flow image by Otsu multiple threshold method. Afterwards, arteries and veins are distinguished by a simple fuzzy criterion based on the information of relative deoxyhemoglobin concentration.
PUMA PROMOTES BAX ACTIVATION IN A FOXO3a-DEPENDENT MANNER IN STS-INDUCED APOPTOSIS
Authors: ZHANG YINGJIE , XING DA
Published: January 2010

PUMA (p53 up-regulated modulator of apoptosis, also called Bbc3) was first identified as a BH3-only Bcl-2 family protein that is transcriptionally up-regulated by p53 and activated upon p53-dependent apoptotic stimuli, such as treatment with DNA-damaging drugs or UV irradiation. Recently, studies have shown that PUMA is also up-regulated in response to certain p53-independent apoptotic stimuli, such as growth factor deprivation or treatment with glucocorticoids or STS (staurosporine). However, the molecular mechanisms of PUMA up-regulation and how PUMA functions in response to p53-independent apoptotic stimuli remain poorly understood. In this study, based on real-time single cell analysis, flow cytometry, and western blotting technique, we investigated the function of PUMA in living human lung adenocarcinoma cells (ASTC-a-1) after STS treatment. Our results show that FOXO3a was activated by STS stimulation and then translocated from cytosol to nucleus. The expression of PUMA was up-regulated via a FOXO3a-dependent manner after STS treatment, while p53 had little function in this process. Moreover, cell apoptosis and Bax activation induced by STS were not blocked by Pifithrin-α (p53 inhibitor), which indicated that p53 was not involved in this signaling pathway. Taken together, these results suggest that PUMA promoted Bax activation in a FOXO3a-dependent pathway during STS-induced apoptosis, while p53 was dispensable in this process.
FAST RECONSTRUCTION METHOD BASED ON COMMON UNIFIED DEVICE ARCHITECTURE (CUDA) FOR MICRO-CT
Authors: QUAN GUOTAO , SUN TANGYOU , DENG YONG
Published: January 2010

Three-dimensional image reconstruction with Feldkamp, Davis, and Kress (FDK) algorithm is the most time consuming part in Micro-CT. The parallel algorithm based on the computer cluster is capable of accelerating image reconstruction speed; however, the hardware is very expensive. In this paper, using the most current graphics processing units (GPU), we present a method based on common unified device architecture (CUDA) for speeding up the Micro-CT image reconstruction process. The most time consuming filtering and back-projection parts of the FDK algorithm are parallelized for the CUDA architecture. The CUDA-based reconstruction speed and image qualities are compared with CPU results for the projecting data of the Micro-CT system. The results show that the 3D image reconstruction speed based on CUDA is ten times faster than the speed with CPU. In conclusion the FDK algorithm based on CUDA for Micro-CT can reconstruct the 3D image right after the end of data acquisition.
APPLICATIONS OF INTRANASAL LOW INTENSITY LASER THERAPY IN SPORTS MEDICINE
Authors: LIU TIMON CHENG-YI , WU DE-FENG , GU ZHI-QIANG , WU MIN
Published: January 2010

Function-specific homeostasis (FSH) has been defined as a negative-feedback response of a biosystem to maintain its interior function-specific conditions so that the function is perfectly performed. There is no photobiomodulation of intranasal low intensity laser therapy (ILILT) on a function in its FSH, but ILILT could modulate a function far from its FSH. This rehabilitation has been found to be mediated by the ratio of intracellular nicotinamide adenine dinucleotide (NAD+) and its reduced form NADH, NAD+/NADH, and then sirtuin 1 (SIRT1). There might be FSH-specific NAD+/NADH (FSN) and SIRT1 activity (FSA). ILILT might enhance NAD+/NADH and SIRT1 activity until they arrive at FSN and FSA, respectively. The NAD+/NADH and SIRT1 activity of related cells of many athletic diseases such as upper respiratory tract infection, asthma, osteoarthritis, exercise-induced muscle damage, wound, traumatic brain injury, and osteoporosis are lower than FSN and FSA, respectively. Therefore, there may be therapeutic effects of ILILT on those athletic diseases. Furthermore, many phenomena and the ILILT mechanism have been integrated to support the prophylaxis effects of ILILT on the swine-origin influenza A (H1N1).
DISCRIMINATIVE ANALYSIS OF FUNCTIONAL NEAR-INFRARED SPECTROSCOPY SIGNALS FOR DEVELOPMENT OF NEUROIMAGING BIOMARKERS OF ELDERLY DEPRESSION
Authors: ZHU YE , JIANG TIANZI , ZHOU YUAN , ZHAO LISHA
Published: January 2010

Functional near-infrared spectroscopy (fNIRS) is a neuroimaging technology which is suitable for psychiatric patients. Several fNIRS studies have found abnormal brain activations during cognitive tasks in elderly depression. In this paper, we proposed a discriminative model of multivariate pattern classification based on fNIRS signals to distinguish elderly depressed patients from healthy controls. This model used the brain activation patterns during a verbal fluency task as features of classification. Then Pseudo-Fisher Linear Discriminant Analysis was performed on the feature space to generate discriminative model. Using leave-one-out (LOO) cross-validation, our results showed a correct classification rate of 88%. The discriminative model showed its ability to identify people with elderly depression and suggested that fNIRS may be an efficient clinical tool for diagnosis of depression. This study may provide the first step for the development of neuroimaging biomarkers based on fNIRS in psychiatric disorders.
TWO-DIMENSIONAL VISUALIZATION OF THE PROPAGATION SPEED OF CORTICAL SPREADING DEPRESSION IN RAT CORTEX
Authors: XU TINGTING , LI PENGCHENG , CHEN SHANGBIN , LUO WEIHUA
Published: January 2010

Cortical spreading depression (CSD), which is a significant pathological phenomenon that correlates with migraines and cerebral ischemia, has been characterized by a wave of depolarization among neuronal cells and propagates across the cortex at a rate of 2–5 mm/min. Although the propagation pattern of CSD was well-investigated using high-resolution optical imaging technique, the variation of propagation speed of CSD across different regions of cortex was not well-concerned, partially because of the lack of ideal approach to visualize two-dimensional distribution of propagation speed of CSD over the whole imaged cortex. Here, we have presented a method to compute automatically the propagation speed of CSD throughout every spots in the imaged cortex. In this method, temporal clustering analysis (TCA) and least square estimation (LSE) were first used to detect origin site where CSD was induced. Taking the origin site of CSD as the origin of coordinates, the data matrix of each image was transformed into the corresponding points based on the polar-coordinate representation. Then, two fixed-distance regions of interest (ROIs) are sliding along with the radial coordinate at each polar angle within the image for calculating the time lag with correlating algorithm. Finally, we could draw a two-dimensional image, in which the value of each pixel represented the velocity of CSD when it spread through the corresponding area of the imaged cortex. The results demonstrated that the method can reveal the heterogeneity of propagation speed of CSD in the imaged cortex with high fidelity and intuition.
Molecular Cytogenetic Characterization of the Human Cerebral Microvessel Endothelial Cell Line hCMEC/D3
Authors: Mkrtchyan H. , Scheler S. , Klein I. , Fahr A. , Couraud P.O. , Romero I.A. , Weksler B. , Liehr T.
Published: January 2010

The immortalized human cerebral microvessel endothelial cell line hCMEC/D3 has been repeatedly used as a model of human blood-brain barrier (BBB). hCMEC/D3 cells between passage 25 and 35 are most often applied in research, remained phenotypically nontransformed, and cells maintained many characteristics of human brain endothelial cells. Also hCMEC/D3 was thought to have conserved a normal diploid karyotype over all these passages. Here we characterized the cell line using high-resolution multicolor fluorescence in situ hybridization (FISH) approaches and revealed a complex karyotype in the 30th passage. Clonal cryptic unbalanced structural rearrangements and numerical aberrations were discovered and described as follows: 45∼48,XX, –X,del(5)(q11)[2],del(9)(q11)[3],+9[3],del(11)(q13∼14)[2], der(14)t(14;21)(q32.33;q22.3)[28],der(15)t(9;15)(p11;p11)[13], dup(15)(p11q11)[5],der(21)t(17;21)(p12;q22)[9],–22[6][cp28]. In summary, a complex karyotype with clonal unbalanced chromosomal rearrangements is present in hCMEC/D3. Thus, we solicit to include molecular cytogenetics in the testing of all cell lines prior to application of their use in complex studies.
Prenatal Three-Dimensional Sonographic Findings Associated with Annular Pancreas
Authors: Dankovcik Robert , Muranska Stela , Kucera Eduard , Jirasek Jan Evangelista , Feyereisl Jaroslav , Sudak Milan , Dudas Marek
Published: January 2010

Annular pancreas is a rare developmental anomaly that accounts for 1% of neonatal intestinal obstructions. For the first time, we describe 3D sonographic findings associated with this condition. In addition to stringent diagnostic criteria based on 2D ultrasound, this case suggests the possible contribution of 3D ultrasound in rare cases of suspected annular pancreas. Verification of prenatal findings was performed during the postnatal surgery.
Fetal Abdominal Lymphangioma Enhanced by Ultrafast MRI
Authors: Cozzi Denis A. , Olivieri Claudio , Manganaro Fabio , Savelli Sara , Giancotti Antonella , Manganaro Lucia
Published: January 2010

Abdominal lymphangioma represents an uncommon congenital anomaly. Herein, we describe an unusual case, which on routine antenatal ultrasonography masqueraded as isolated ascites. Subsequent fetal MRI at 27 weeks’ gestation implemented antenatal assessment of the lesion, prompting further investigations and straightforward postnatal treatment. Fetal MRI represents a valuable adjunct to antenatal ultrasonography for the evaluation of cystic abdominal masses.