bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence of obesity among Portuguese children (6–8 years old) using three definition criteria: COSI Portugal, 2008
Authors: Rito A. , Wijnhoven T. M. A. , Rutter H. , Carvalho M. A. , Paixão E. , Ramos C. , Claudio D. , Espanca R. , Sancho T. , Cerqueira Z. , Carvalho R. , Faria C. , Feliciano E. , Breda J.
Published: August 2012

What is already known about this subject?

Obesity is at epidemic levels and presents a serious global public health challenge.

Portugal is one of the European countries with the highest prevalence of childhood obesity.

Childhood Obesity Surveillance Initiative (COSI) is a robust monitoring system covering similar age groups, using standardized methods that allows comparability with other WHO European Region Member States.

What this study adds?

In Portugal, one in every three of 6‐ to 8‐year‐old children are overweight.

Compared with other COSI national surveys, a similar trend was observed in other southern European countries, particularly Italy.

The reference method used to define overweight and obesity is important as it provides different estimates.

Introduction

Previous studies place Portugal among the five countries with the highest prevalence of childhood obesity in Europe. This paper describes the prevalence of thinness, overweight and obesity in Portuguese children of 6–8 years of age, based on the first data collection from Childhood Obesity Surveillance Initiative Portugal, which took place during the 2007/2008 school year.

Methods

This study uses a semi‐longitudinal design with repeated cross‐sectional national representative samples. Specific prevalence of overweight (including obesity) and obesity was determined using three different diagnostic criteria. Across the seven geographic regions, 3765 children were enrolled from 181 schools; 50.3% of participants were males.

Results

Using the International Obesity Task Force reference, the prevalence of thinness, overweight and obesity were 4.8%, 28.1% and 8.9%, respectively; using the Center for Disease Control and Prevention reference they were 2.1%, 32.2% and 14.6%, respectively; and according to the World Health Organization reference, they were 1.0%, 37.9% and 15.3%, respectively. Univariate analysis showed a higher risk of obesity in older children, in boys and in the Azores region. The islands of Madeira and the Azores were the regions with the highest prevalence of overweight at 39.4% and 46.6%, respectively, and Algarve was the one with the lowest (21.4%).

Conclusion

These findings demonstrate the need for urgent action in Portugal and provide policy‐makers with comprehensive and detailed information to assist with this.
Exergy, Economic, and Environmental Analysis of a PEM Fuel Cell Power System to Meet Electrical and Thermal Energy Needs of Residential Buildings
Authors: Ashari G. R. , Ehyaei M. A. , Mozafari A. , Atabi F. , Hajidavalloo E. , Shalbaf S.
Published: August 2012

In this paper, a Polymer Electrolyte Membrane (PEM) fuel cell power system including burner, steam reformer, heat exchanger, and water heater has been considered. A PEM fuel cell system is designed to meet the electrical, domestic hot water, heating, and cooling loads of a residential building located in Tehran. Operating conditions of the system with consideration of the electricity cost has been studied. The cost includes social cost of the environmental pollutants (e.g. CO2, CO and NO). The results show that the maximum energy needs of the building can be met by 12 fuel cell stacks with nominal capacity of 8.5 kW. Annual average electricity cost of thissystem is equal to 0.39 US$/kWh and entropy generation of this system through a year is equal to 1004.54 GJ/K1. It is also concluded that increase in ambient temperature from 1 °C to 40 °C increases the entropy generation by 5.73%, carbon monoxide by 14.56%, and nitrogen monoxide by 8.9%, but decreases carbon dioxide by 0.47%.
Critique and Improvement of a One-Dimensional Semianalytical Model of a Direct Methanol Fuel Cell
Authors: Kuo C. C. , Lear W. E. , Fletcher J. H. , Crisalle O. D.
Published: August 2012

A constructive critique and a suite of proposed improvements for a recent one-dimensional semianalytical model of a direct methanol fuel cell are presented for the purpose of improving the predictive ability of the modeling approach. The model produces a polarization curve for a fuel cell system comprised of a single membrane-electrode assembly, based on a semianalytical one-dimensional solution of the steady-state methanol concentration profile across relevant layers of the membrane electrode assembly. The first improvement proposed is a more precise numerical solution method for an implicit equation that describes the overall current density, leading to better convergence properties. A second improvement is a new technique for identifying the maximum achievable current density, an important piece of information necessary to avoid divergence of the implicit-equation solver. Third, a modeling improvement is introduced through the adoption of a linear ion-conductivity model that enhances the ability to better match experimental polarization-curve data at high current densities. Fourth, a systematic method is advanced for extracting anodic and cathodic transfer-coefficient parameters from experimental data via a least-squares regression procedure, eliminating a potentially significant parameter estimation error. Finally, this study determines that the methanol concentration boundary condition imposed on the membrane side of the membrane-cathode interface plays a critical role in the model’s ability to predict the limiting current density. Furthermore, the study argues for the need to carry out additional experimental work to identify more meaningful boundary concentration values realized by the cell.
In-Situ Continuous Coke Deposit Removal by Catalytic Steam Gasification for Fuel-Cooled Thermal Management
Authors: Huang He , Tang Xia , Haas Martin
Published: August 2012

Fuel-cooled thermal management, including endothermic cracking and reforming of hydrocarbon fuels, is an enabling technology for advanced aero engines and offers potential for cycle improvements and pollutant emissions control. The principal engine operability issue that will affect this enabling hydrocarbon fuel cooling technology is coke formation and deposition. Furthermore, the extent to which the benefits of high heat sink cooling technology can be realized is directly related to our ability to suppress coke formation and deposition. The successful implementation of this enabling technology is, therefore, predicated on coke suppression. In situ continuous coke deposit removal by catalytic steam gasification is being developed and successfully demonstrated as a means for suppressing pyrolytic coke deposit in fuel-cooled thermal management systems for advanced aero engines. The objective of this research is to investigate the in situ continuous coke deposit removal by catalytic steam gasification for suppressing pyrolytic coke deposition using a single-tube reactor simulator under representative hypersonic operating conditions. A coke removal system removes coke deposit from the walls of a high temperature passage in which hydrocarbon fuel is present. The system includes a carbon-steam gasification catalyst and a water source. The carbon-steam gasification catalyst is applied to the walls of the high temperature passage. The water reacts with the coke deposit on the walls of the fuel passage side to remove the coke deposit from the walls by carbon-steam gasification in the presence of the carbon-steam gasification catalyst. Experimental data shows the in situ continuous coke deposit removal by catalytic steam gasification is able to reduce coke deposit rate by more than ten times.
An Energy-Based Axial Isothermal-Mechanical Fatigue Lifing Method
Authors: Wertz John , Letcher Todd , Herman Shen M.-H. , Scott-Emuakpor Onome , George Tommy , Cross Charles
Published: August 2012

An energy-based fatigue lifing method for the determination of the full-life and critical-life of in-service structures subjected to axial isothermal-mechanical fatigue (IMF) has been developed. The foundation of this procedure is the energy-based axial room-temperature lifing model, which states: the total strain energy dissipated during both a quasi-static process and a dynamic (fatigue) process is the same material property. The axial IMF lifing framework is composed of the following entities: (1) the development of an axial IMF testing capability; (2) the creation of a testing procedure capable of assessing the strain energy dissipated during both a quasi-static process and a dynamic process at elevated temperatures; and (3) the incorporation of the effect of thermal loading into the axial fatigue lifing model. Both an axial IMF capability and a detailed testing procedure were created. The axial IMF capability was employed to produce full-life and critical-life predictions as functions of temperature, which were shown to have an excellent correlation with experimental fatigue data. For the highest operating temperature, the axial IMF full-life prediction was compared to lifing predictions made by both the universal slopes and the uniform material law prediction and was found to be more accurate at an elevated temperature.
Site-Specific Quantification of Bone Quality Using Highly Nonlinear Solitary Waves
Authors: Yang Jinkyu , Sangiorgio Sophia N. , Borkowski Sean L. , Silvestro Claudio , De Nardo Luigi , Daraio Chiara , Ebramzadeh Edward
Published: August 2012

Osteoporosis is a well recognized problem affecting millions of individuals worldwide. The ability to diagnose problems in an effective, efficient, and affordable manner and identify individuals at risk is essential. Site-specific assessment of bone mechanical properties is necessary, not only in the process of fracture risk assessment, but may also be desirable for other applications, such as making intraoperative decisions during spine and joint replacement surgeries. The present study evaluates the use of a one-dimensional granular crystal sensor to measure the elastic properties of bone at selected locations via direct mechanical contact. The granular crystal is composed of a tightly packed chain of particles that interact according to the Hertzian contact law. Such chains represent one of the simplest systems to generate and propagate highly nonlinear acoustic signals in the form of compact solitary waves. First, we investigated the sensitivity of the sensor to known variations in bone density using a synthetic cancellous bone substitute, representing clinical bone quality ranging from healthy to osteoporotic. Once the relationship between the signal response and known bone properties was established, the sensor was used to assess the bone quality of ten human cadaveric specimens. The efficacy and accuracy of the sensor was then investigated by comparing the sensor measurements with the bone mineral density (BMD) obtained using dual-energy x-ray absorptiometry (DEXA). The results indicate that the proposed technique is capable of detecting differences in bone quality. The ability to measure site-specific properties without exposure to radiation has the potential to be further developed for clinical applications.
Investigation of four‐dimensional (4D) Monte Carlo dose calculation in real‐time tumor tracking stereotatic body radiotherapy for lung cancers
Authors: Chan Mark K. H. , Kwong Dora L. W. , Ng Sherry C. Y. , Tam Eric K. W. , Tong Anthony S. M.
Published: August 2012

Purpose:

To investigate the dosimetric variations and radiobiological impacts as a consequence of delivering treatment plans of 3D nature in 4D manner based on the 4D Monte Carlo treatment planning framework implemented on Cyberknife.

Methods:

Dose distributions were optimized on reference 3D images at end of exhale phase of a 4DCT dataset for 25 lung cancer patients treated with 60 Gy/3Fx or 48 Gy/4Fx. Deformable image registrations between individual 3DCT images to the reference 3DCT image in the 4DCT study were performed to interpolate doses calculated on multiple anatomical geometries back on to the reference geometry to compose a 4D dose distribution that included the tracking beam motion and organ deformation. The 3D and 4D dose distributions that were initially calculated with the equivalent path‐length (EPL) algorithm (3DEPL dose and 4DEPL dose) were recalculated with the Monte Carlo algorithm (3DMC dose and 4DMC dose). Dosimetric variations of V60Gy/48Gy and D99 of GTV, mean doses to the lung and the heart and maximum dose (D1) of the spinal cord as a consequence of tracking beam motion in deforming anatomy, dose calculation algorithm, and both were quantified by the relative change from 4DMC to 3DMC doses, from 4DMC to 4DEPL doses, and from 4DMC to 3DEPL doses, respectively.

Results:

Comparing 4DMC to 3DEPL plans, V60Gy / 48Gy and D99 of GTV decreased considerably by 13 ± 22% (mean ± 1SD) and 9.2 ± 5.5 Gy but changes of normal tissue doses were not more than 0.5 Gy on average. The generalized equivalent uniform dose (gEUD) and tumor control probability (TCP) were reduced by 14.3 ± 8.8 Gy and 7.5 ± 5.2%, and normal tissue complication probability (NTCP) for myelopathy and pericarditis were close to zero and NTCP for radiation pneumonitis was reduced by 2.5% ± 4.1%. Comparing 4DMC to 4DEPL plans found decreased V60Gy/48Gy and D99 by 12.3% ± 21.6% and 7.3 ± 5.3 Gy, the normal tissues doses by 0.5 Gy on average, gEUD and TCP by 13.0 ± 8.6 Gy and 7.1% ± 5.1%. Comparing 4DMC to 3DMC doses, V60Gy/48Gy and D99 of GTV was reduced by 5.2% ± 8.8% and 2.6 ± 3.3 Gy, and normal tissues hardly changed from 4DMC to 3DMC doses. The corresponding decreases of gEUD and TCP were 2.8 ± 4.0 Gy and 1.6 ± 2.4%.

Conclusions:

The large discrepancy between original 3DEPL plan and benchmarking 4DMC plan is predominately due to dose calculation algorithms as the tracking beam motion and organ deformation hardly influenced doses of normal tissues and moderately decreased V60Gy/48Gy and D99 of GTV. It is worth to make a thoughtful weight of the benefits of full 4DMC dose calculation and consider 3DMC dose calculation as a compromise of 4DMC dose calculation considering the multifold computation time.
Predatory Fish Select for Coordinated Collective Motion in Virtual Prey
Authors: Ioannou C. C. , Guttal V. , Couzin I. D.
Published: August 2012

Evolving Group Formation

Grouping behavior in prey species has long been thought to constitute an adaptation against predation; however, it has been difficult to characterize the mechanisms by which predator selection shapes prey movement and grouping behavior. Using an approach that combines the selection imposed by a live predator, the bluegill sunfish, with manipulation of computer-generated “prey,”

Ioannou
et al.

(p.
1212
, published online 16 August; see the Perspective by
Romey
) show that “prey” that behave as a group are more likely to survive that those that move in other ways.
Photo-Tautomerization of Acetaldehyde to Vinyl Alcohol: A Potential Route to Tropospheric Acids
Authors: Andrews Duncan U. , Heazlewood Brianna R. , Maccarone Alan T. , Conroy Trent , Payne Richard J. , Jordan Meredith J. T. , Kable Scott H.
Published: August 2012

Enols in the Atmosphere?

Keto/enol tautomerization (HC−C=O→C=C−OH) plays a central role in the chemistry of carbonyl compounds in a solution in which solvent and catalytic acids or bases can facilitate the proton transfer from C to O and back again. In contrast, analyses of atmospheric chemistry tend to exclude enol structure, on the assumption that tautomerization does not proceed regularly in gas phase.

Andrews
et al.

(p.
1203
, published online 16 August) used isotopic labeling to probe the photoisomerization pathway of gaseous acetaldehyde in the lab and discovered evidence for an enol. Subsequent modeling indicates that photogenerated enols could build up sufficiently in the troposphere to account for previously puzzling observations of organic acids in the atmosphere.
The Precise Solar Shape and Its Variability
Authors: Kuhn J. R. , Bush R. , Emilio M. , Scholl I. F.
Published: August 2012

Our Constant Sun

The exact shape of the Sun provides information on its internal structure. Based on data obtained by the Helioseismic and Magnetic Imager aboard NASA's Solar Dynamics Observatory,

Kuhn
et al.

(p.
1638
, published online 16 August; see the Perspective by

Gough

) measured the solar shape during a 2-year period in which the Sun evolved from a minimum to a maximum of sunspot activity. Against expectations, the Sun's oblate shape was found to be constant and not to vary with the 11-year solar cycle.
Next-Generation Digital Information Storage in DNA
Authors: Church George M. , Gao Yuan , Kosuri Sriram
Published: August 2012

Digital information can be stored in DNA at densities higher than digital media such as flash memory or quantum holography.
Equity of access to specialist chronic fatigue syndrome (CFS/ME) services in England (2008–2010): a national survey and cross-sectional study
Authors: Collin Simon M , Sterne Jonathan A C , Hollingworth William , May Margaret T , Crawley Esther
Published: August 2012

Objectives

Provision of National Health Service (NHS) specialist chronic fatigue syndrome or myalgic encephalomyelitis (CFS/ME) services in England has been deemed patchy and inconsistent. Our objective was to explore variation in the provision of NHS specialist CFS/ME services and to investigate whether access is related to measures of deprivation and inequality.

Design

Survey of all CFS/ME clinical teams in England, plus cross-sectional data from a subset of teams.

Setting

Secondary care.

Outcome measures

We used clinic activity data from CFS/ME clinical teams in England to describe provision of specialist CFS/ME services (referral, assessment and diagnosis rates per 1000 adults per year) during 2008–2011 according to Primary Care Trust (PCT) population estimates, and to investigate whether use of services was related to PCT-level measures of deprivation and inequality. We used postcode data from seven services to investigate variation in provision by deprivation.

Results

Clinic activity data were obtained from 93.9% (46/49) of clinical teams in England which between them received referrals from 84.9% (129/152) of PCTs. 12 PCTs, covering a population of 2.08 million adults, provided no specialist CFS/ME service. There was a six-fold variation in referral and assessment rates between services which could not be explained by PCT-level measures of deprivation and inequality. The median assessment rate in 2010 was 0.25 (IQR 0.17, 0.35) per 1000 adults per year. 91.9% (IQR 76.5%, 100.0%) of adults assessed were diagnosed with CFS/ME. Postcode data from seven clinical teams showed that assessment rates were equal across deprivation quartiles for four teams but were 40–50% lower in the most deprived compared with the most affluent areas for three teams.

Conclusions

Two million adults in England do not have access to a specialist CFS/ME service. In some areas which do have a specialist service, access is inequitable. This inequity may worsen with the impending fragmentation of NHS commissioning across England.
TWO MODULI SPACES OF ABELIAN FOURFOLDS WITH AN AUTOMORPHISM OF ORDER FIVE
Authors: VAN GEEMEN BERT , SCHÜTT MATTHIAS
Published: August 2012

We find explicit projective models of a compact Shimura curve and of a (non-compact) surface which are the moduli spaces of principally polarized abelian fourfolds with an automorphism of order five. The surface has a 24-nodal canonical model in P4 which is the complete intersection of two S5-invariant cubics. It is dominated by a Hilbert modular surface and we give a modular interpretation for this. We also determine the L-series of these varieties as well as those of several modular covers of the Shimura curve.
ON THE PLANAR ALGEBRA OF OCNEANU'S ASYMPTOTIC INCLUSION
Authors: CURRAN STEPHEN
Published: August 2012

In recent joint work with Jones and Shlyakhtenko, we have given a diagrammatic description of Popa's symmetric enveloping inclusion for planar algebra subfactors. In this paper, we give a diagrammatic construction of the associated Jones tower, in the case that the planar algebra is finite-depth. We then use this construction to describe the planar algebra of the symmetric enveloping inclusion, which is known to be isomorphic to the planar algebra of Ocneanu's asymptotic inclusion by a result of Popa. As an application we give a planar algebraic computation of the (reduced) fusion algebra of the asymptotic inclusion, recovering some well-known results of Ocneanu and Evans–Kawahigashi.
KNOWLEDGE REDUCTION IN LATTICE-VALUED INFORMATION SYSTEMS WITH INTERVAL-VALUED INTUITIONISTIC FUZZY DECISION
Authors: XU WEI-HUA , LIU SHI-HU , YU FU-SHENG
Published: August 2012

In this paper, associated with dominance relation, lattice theory and intuitionistic fuzzy sets theory, the lattice-valued information systems with interval-valued intuitionistic fuzzy decision are proposed and some of its properties are investigated carefully. And, an approach to knowledge reduction based on discernibility matrix in consistent lattice-valued information systems with interval-valued intuitionistic fuzzy decision is constructed and an illustrative example is applied to show its validity. Moreover, extended from the idea of knowledge reduction in consistent information systems, four types of reductions and approaches to obtaining the knowledge reductions of the inconsistent lattice-valued information systems with interval-valued intuitionistic fuzzy decision are formulated via the use of discernibility matrix. Furthermore, examples are considered to show that the approaches are useful and effective. One can obtain that the research is meaningful both in theory and in application for the issue of knowledge reduction in complex information systems.
IMMUNOLOGY AND ARTIFICIAL IMMUNE SYSTEMS
Authors: MALIM MUHAMMAD ROZI , HALIM FARIDAH ABDUL
Published: August 2012

Artificial immune system is inspired by the natural immune system for solving computational problems. The immunological principles that are primarily used in artificial immune systems are the clonal selection principle, the immune network theory, and the negative selection mechanism. These principles have been applied in anomaly detection, pattern recognition, computer and network security, dynamic environments and learning, robotics, data analysis, optimization, scheduling, and timetabling. This paper describes how these three immunological principles were adapted by previous researchers in their artificial immune system models and algorithms. Finally, the applications of various artificial immune systems to various domains are summarized as a time-line.
FIRST-ORDER LOGIC RULE INDUCTION FOR INFORMATION EXTRACTION IN WEB RESOURCES
Authors: FERNÁNDEZ-VILLAMOR JOSÉ IGNACIO , IGLESIAS CARLOS ÁNGEL , GARIJO MERCEDES
Published: August 2012

Information extraction out of web pages, commonly known as screen scraping, is usually performed through wrapper induction, a technique that is based on the internal structure of HTML documents. As such, the main limitation of these kinds of techniques is that a generated wrapper is only useful for the web page it was designed for. To overcome this, in this paper it is proposed a system that generates first-order logic rules that can be used to extract data from web pages. These rules are based on visual features such as font size, elements positioning or types of contents. Thus, they do not depend on a document's internal structure, and are able to work on different sites. The system has been validated on a set of different web pages, showing very high precision and good recall, which validates the robustness and the generalization capabilities of the approach.
STRING FORMATION AND OBSTACLE AVOIDANCE FOR MULTIPLE AUTONOMOUS AGENTS
Authors: YAN JING , GUAN XIN-PING , LUO XIAO-YUAN , YANG XIAN
Published: August 2012

A novel pursuit-based approach is presented to investigate string formation and obstacle avoidance for multiple autonomous agents. The control objective for these agents is to reach a final desired position along a collision-free trajectory. First, a line formation is achieved by using a leader-follower strategy, in which one agent is regarded as the leader and the others are followers. By using the receding horizon control, the leader agent can reach the destination while effectively avoiding collision with obstacles evolving in environment. The information on obstacles is incorporated online as they are detected by sensors with a limited detecting range. Moreover, each follower agent should only pursue its front agent. It turns out that the follower agents can keep a string formation with the leader agent wherein the string formation is useful for a fleet of agents driving in a platoon sequence on a road. The system stability can be guaranteed with a terminal-state penalty in the cost function and a terminal-state region in the optimal control problem. Finally, simulation studies are provided to verify the effectiveness of the proposed approach.
A SPECTRUM FOR α-REGULAR UNKNOTS
Authors: CALVO JORGE ALBERTO , PILE ANGELA L.
Published: August 2012

The conformation space of α-regular knots, that is, of spatial polygons which are both equilateral and equiangular, has been investigated by both chemists and mathematicians for quite some time. More recently, the study of α-regular stick numbers, the minimum number of sticks needed to create an α-regular polygon representing a given knot, has also gained some traction. In most of these studies, the value of the angle α has been a fixed constant, playing a secondary role to the number of edges in the polygon or its knot type. In this paper, we consider the entire spectrum of minimal α-regular stick numbers for a knot as a function of α. In particular, we compute this spectrum for the special case of the unknot.
HUMAN POWER ASSIST SYSTEM WITH POWER-DAMPED BUT PERCEIVABLE OPERATING FORCE INFORMATION FEEDBACK
Authors: YU YONG , YOSHIMITSU DAISUKE , HAYASHI RYOTA
Published: August 2012

This research considers a human-limb power assist system, which can feedback the power-damped but perceivable operating force information to human. The system can be easily suitable to a person without using EMG sensor and knowing limb's mass, viscosity and elasticity. The control method, transmission ratio, perceivable force change and system unit are discussed in this paper. Lastly, experimental verification on the proposed approach is performed and its results are outlined.
Epitaxial Growth of AlGaN/GaN High-Electron Mobility Transistor Structure on Diamond (111) Surface
Authors: Hirama Kazuyuki , Taniyasu Yoshitaka , Kasu Makoto
Published: August 2012

Epitaxial growth of an AlGaN/GaN high-electron mobility trainsistor (HEMT) structure on a diamond (111) substrate was investigated. Due to the misorientation of the diamond (111) surface, the AlGaN/GaN HEMT structure showed the macro-step surface. Using diamond surfaces with two different misorientation angles (3 and 0.5°), we found that the one with the small misorientation angle is effective for obtaining a flat AlGaN/GaN HEMT surface. Threading dislocation density of the AlGaN/GaN HEMT structure grown on the diamond (111) surface was evaluated from cross-sectional transmission electron microscope images. The densities of pure-screw-, pure-edge- and mixed-type threading dislocation were 0.3×109, 4.1×109, and 4.5×109 cm-2, respectively. The AlGaN/GaN HEMT eptaxially grown on the diamond (111) substrate showed the maximum drain current of 800 mA/mm with little self-heating effect.
Synthesis of Diamond-Like Carbon Films on Planar and Non-Planar Geometries by the Atmospheric Pressure Plasma Chemical Vapor Deposition Method
Authors: Noborisaka Mayui , Hirako Tomoaki , Shirakura Akira , Watanabe Toshiyuki , Morikawa Masashi , Seki Masaki , Suzuki Tetsuya
Published: August 2012

Diamond-like carbon (DLC) films were synthesized by the dielectric barrier discharge-based plasma deposition at atmospheric pressure and their hardness and gas barrier properties were measured. A decrease in size of grains and heating substrate temperature improved nano-hardness up to 3.3 GPa. The gas barrier properties of DLC-coated poly(ethylene terephthalate) (PET) sheets were obtained by 3–5 times of non-coated PET with approximately 0.5 µm in film thickness. The high-gas-barrier DLC films deposited on PET sheets are expected to wrap elevated bridge of the super express and prevent them from neutralization of concrete. We also deposited DLC films inside PET bottles by the microwave surface-wave plasma chemical vapor deposition (CVD) method at near-atmospheric pressure. Under atmospheric pressure, the films were coated uniformly inside the PET bottles, but did not show high gas barrier properties. In this paper, we summarize recent progress of DLC films synthesized at atmospheric pressure with the aimed of food packaging and concrete pillar.
Nanoindentation Fracture Behaviors of Diamond-Like Carbon Film on Aluminum Alloy with Different Interface Toughnesses
Authors: Nose Kenji , Sasaki Yuto , Kamiko Masao , Mitsuda Yoshitaka
Published: August 2012

Fracture behaviors of a diamond-like carbon (DLC) film on an aluminum alloy (AA2017) were analyzed by a nanoindentation test under conditions of deep and full penetrations of an indenter tip through the DLC film. The interface structure between the DLC and AA2017 was modified by using the substrate sputtering and redeposition (SSRD) method. The films deposited with a shorter (30 min) SSRD duration showed weak adhesion to the substrate and often resulted in wide delamination from the impressions. At the same time, films deposited with a longer (120 min) SSRD duration showed no such delamination. Obvious brittle fractures were detected in the load-displacement curves mainly in the film with the short SSRD duration. These results suggest that a long SSRD inhibited the delamination of the DLC film from AA2017 under local and strong stress conditions because of the improved interface toughness.
Activated hepatic stellate cells upregulate transcription of ecto-5′-nucleotidase/CD73 via specific SP1 and SMAD promoter elements
Authors: Fausther Michel , Sheung Nina , Saiman Yedidya , Bansal Meena B. , Dranoff Jonathan A.
Published: August 2012

Adenosine is a potent modulator of liver fibrosis and inflammation. Adenosine has been shown to regulate such diverse activities as chemotaxis, contraction, and matrix production in hepatic stellate cells (HSC). Ecto-5′-nucleotidase/CD73 [EC 3.1.3.5] is the rate-limiting enzyme in adenosine production. Cd73-deficient mice are resistant to experimental liver fibrosis and have impaired adenosine generation. However, cell-specific expression and regulation of CD73 within the fibrotic liver have not been defined. In particular, prior evidence demonstrating that liver myofibroblasts, the cells believed to be responsible for matrix formation in the liver, express CD73 is lacking. Thus we tested the hypothesis that HSC and portal fibroblasts (PF), cells that undergo differentiation into liver myofibroblasts, express CD73 in a regulated fashion. We found that CD73 is weakly expressed in quiescent HSC and PF but is markedly upregulated at the transcriptional level in myofibroblastic HSC and PF. We furthermore found that CD73 protein and its functional activity are strongly increased in fibrous septa in rats subjected to experimental fibrosis. To determine the mechanism for the upregulation of Cd73 gene, we cloned the rat Cd73 promoter and then used serial truncation and site-directed mutagenesis to identify key regulatory elements. We identified two consensus SP1 motifs and one SMAD binding site, each of which was necessary for Cd73 gene upregulation. In conclusion, activated HSC upregulate Cd73 gene expression, via specific SP1 and SMAD promoter elements, after myofibroblastic differentiation. The ecto-5′-nucleotidase/CD73 enzyme is a novel cellular marker of activated liver myofibroblasts in vivo and in vitro and thus represents a promising molecular target for antifibrotic therapies in liver diseases.
PGC-1α overexpression results in increased hepatic fatty acid oxidation with reduced triacylglycerol accumulation and secretion
Authors: Morris E. Matthew , Meers Grace M. E. , Booth Frank W. , Fritsche Kevin L. , Hardin Christopher D. , Thyfault John P. , Ibdah Jamal A.
Published: August 2012

Studies have shown that decreased mitochondrial content and function are associated with hepatic steatosis. We examined whether peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) overexpression and a subsequent increase in mitochondrial content and function in rat primary hepatocytes (in vitro) and Sprague-Dawley rats (in vivo) would comprehensively alter mitochondrial lipid metabolism, including complete (CO2) and incomplete (acid-soluble metabolites) fatty acid oxidation (FAO), tricarboxylic acid cycle flux, and triacylglycerol (TAG) storage and export. PGC-1α overexpression in primary hepatocytes produced an increase in markers of mitochondrial content and function (citrate synthase, mitochondrial DNA, and electron transport system complex proteins) and an increase in FAO, which was accompanied by reduced TAG storage and TAG secretion compared with control. Also, the PGC-1α-overexpressing hepatocytes were protected from excess TAG accumulation following overnight lipid treatment. PGC-1α overexpression in hepatocytes lowered expression of genes critical to VLDL assembly and secretion (apolipoprotein B and microsomal triglyceride transfer protein). Adenoviral transduction of rats with PGC-1α resulted in a liver-specific increase in PGC-1α expression and produced an in vivo liver phenotype of increased FAO via increased mitochondrial function that also resulted in reduced hepatic TAG storage and decreased plasma TAG levels. In conclusion, overexpression of hepatic PGC-1α and subsequent increases in FAO through elevated mitochondrial content and/or function result in reduced TAG storage and secretion in the in vitro and in vivo milieu.
Role of lipase-generated free fatty acids in converting mesenteric lymph from a noncytotoxic to a cytotoxic fluid
Authors: Qin Xiaofa , Dong Wei , Sharpe Susan M. , Sheth Sharvil U. , Palange David C. , Rider Therese , Jandacek Ronald , Tso Patrick , Deitch Edwin A.
Published: August 2012

Recent studies have shown that mesenteric lymph plays a very important role in the development of multiple-organ dysfunction syndrome under critical conditions. Great efforts have been made to identify the biologically active molecules in the lymph. We used a trauma-hemorrhagic shock (T/HS) model and the superior mesenteric artery occlusion (SMAO) model, representing a global and a localized intestinal ischemia-reperfusion insult, respectively, to investigate the role of free fatty acids (FFAs) in the cytotoxicity of mesenteric lymph in rats. Lymph was collected before, during, and after (post) shock or SMAO. The post-T/HS and SMAO lymph, but not the sham lymph, manifested cytotoxicity for human umbilical vein endothelial cells (HUVECs). HUVEC cytotoxicity was associated with increased FFAs, especially the FFA-to-protein ratio. Addition of albumin, especially delipidated albumin, reduced this cytotoxicity. Lipase treatment of trauma-sham shock (T/SS) lymph converted it from a noncytotoxic to a cytotoxic fluid, and its toxicity correlated with the FFA-to-protein ratio in a fashion similar to that of the T/HS lymph, further suggesting that FFAs were the key components leading to HUVEC cytotoxicity. Analysis of lymph by gas chromatography revealed that the main FFAs in the post-T/HS or lipase-treated T/SS lymph were palmitic, stearic, oleic, and linoleic acids. When added to the cell culture at levels comparable to those in T/HS lymph, all these FFAs were cytotoxic, with linoleic acid being the most potent. In conclusion, this study suggests that lipase-generated FFAs are the key components resulting in the cytotoxicity of T/HS and SMAO mesenteric lymph.
A quantitative analysis of electrolyte exchange in the salivary duct
Authors: Patterson Kate , Catalán Marcelo A. , Melvin James E. , Yule David I. , Crampin Edmund J. , Sneyd James
Published: August 2012

A healthy salivary gland secretes saliva in two stages. First, acinar cells generate primary saliva, a plasma-like, isotonic fluid high in Na+ and Cl−. In the second stage, the ducts exchange Na+ and Cl− for K+ and HCO3−, producing a hypotonic final saliva with no apparent loss in volume. We have developed a tool that aims to understand how the ducts achieve this electrolyte exchange while maintaining the same volume. This tool is part of a larger multiscale model of the salivary gland and can be used at the duct or gland level to investigate the effects of genetic and chemical alterations. In this study, we construct a radially symmetric mathematical model of the mouse salivary gland duct, representing the lumen, the cell, and the interstitium. For a given flow and primary saliva composition, we predict the potential differences and the luminal and cytosolic concentrations along a duct. Our model accounts well for experimental data obtained in wild-type animals as well as knockouts and chemical inhibitors. Additionally, the luminal membrane potential of the duct cells is predicted to be very depolarized compared with acinar cells. We investigate the effects of an electrogenic vs. electroneutral anion exchanger in the luminal membrane on concentration and the potential difference across the luminal membrane as well as how impairing the cystic fibrosis transmembrane conductance regulator channel affects other ion transporting mechanisms. Our model suggests the electrogenicity of the anion exchanger has little effect in the submandibular duct.
Comparative study between original and traditional method in establishing a chronic sinus node damage model in rabbit
Authors: Liu Ru-xiu , Wang Yan-li , Li Hui-bo , Wang Ni-na , Bao Mei-jing , Xu Li-ya
Published: August 2012

Sick Sinus Syndrome is a common and refractory arrhythmia, needing further study in which setting up a credible sinus node damage model is important. To explore the feasibility and superiority of an original formaldehyde pinpoint pressing permeation (FPPP) method for building a chronic sinus node damage (CSND) model, 5 rabbits were chosen from 35 as a sham-operation group, and the remaining were randomly divided into two groups: the formaldehyde wet compressing (FWC) group, in which models were established by applying a cotton bud dipped in 20% formaldehyde onto the sinus node (SN) area, and the FPPP group, in which models were established by injecting formaldehyde into the SN area through a self-made pinpointing and injecting electrode. We found that in both groups, the HR at 2 h, 24 h, 1 wk, and 2 wk after modeling decreased compared with premodeling; sinoatrial conduction time, sinus node recovery time, and corrected sinus node recovery time were prolonged compared with premodeling. The indexes mentioned shortened by 2 wk after modeling compared with 2 h in the FWC group, whereas they were stable after modeling in the FPPP group. The modeling achievement ratio in the FPPP group was higher and the death rate was lower. Under light microscope, paraffin sections of the SN tissue and cells showed severe injury in both groups. The results indicate that the CSND models in rabbits can be successfully established by the FPPP method, with higher achievement ratio, lower death rate, better stabilization effect, and less damaging comparing with the traditional method.
The combination of theophylline and endothelin receptor antagonism improves exercise performance of rats under simulated high altitude
Authors: Radiloff Daniel R. , Zhao Yulin , Boico Alina , Wu Chan , Shan Siqing , Palmer Gregory , Hamilton Karyn , Irwin David , Hanna Gabi , Piantadosi Claude A. , Schroeder Thies
Published: August 2012

Decreased physical performance is a well-known consequence of rapid ascent to high altitude. Hypoxic pulmonary vasoconstriction (HPV) potentially limits cardiac output and systemic blood flow, thus preventing successful adaptation to rapid ascent. We hypothesized that pharmacological enhancement of the heart rate with theophylline, combined with reversal of HPV via endothelin blockade, could increase exercise performance at high altitude. Female Sprague-Dawley rats were treated with combinations of 1) theophylline, 2) the endothelin receptor antagonists sitaxsentan/ambrisentan, and/or 3) phosphodiesterase-5 inhibitor sildenafil and exposed to either a simulated high altitude (4,267 m) or 12% oxygen. Exercise capacity, peripheral blood flow, hemodynamics, and pulmonary leak were examined. Combination treatment with theophylline and endothelin blockade, but not with the respective single compounds, significantly prolonged run-to-fatigue time under simulated high altitude. No such efficacy was found when theophylline was combined with sildenafil. Neither theophylline nor sitaxsentan or their combination influenced breathing rates and hemoglobin oxygen saturation. Whereas under hypoxia, theophylline significantly increased muscular blood flow, and sitaxsentan increased tissue oxygenation, the combination improved both parameters but in a reduced manner. Under hypoxia, the combination treatment but not the single compounds significantly enhanced pulmonary arterial pressure compared with controls (13.1 ± 6.3 vs. 11.9 ± 5.2 mmHg), whereas mean arterial pressure remained unaffected. Pulmonary wet-to-dry weight ratios were unaffected by combination treatment. We conclude that concomitant dosing with a cardiac stimulant and endothelin antagonist can partially reverse loss of physical performance capacity under hypobaric hypoxia, independent from improving blood oxygen saturation.
Bone Micro-CT Assessments in an Orchidectomised Rat Model Supplemented withEurycoma longifolia
Authors: Ramli Rosmaliza , Khamis Mohd Fadhli , Shuid Ahmad Nazrun
Published: August 2012

Recent studies suggested thatEurycoma longifolia, a herbal plant, may have the potential to treat osteoporosis in elderly male. This study aimed to determine the effects ofEurycoma longifoliasupplementation on the trabecular bone microarchitecture of orchidectomised rats (androgen-deficient osteoporosis model). Forty-eight-aged (10–12 months old)Sprague Dawleyrats were divided into six groups of sham-operated (SHAM), orchidectomised control (ORX), orchidectomised + 7 mg/rat testosterone enanthate (TEN) and orchidectomised +Eurycoma longifolia30 mg/kg (EL30), orchidectomised +Eurycoma longifolia60 mg/kg (EL60), orchidectomised +Eurycoma longifolia90 mg/kg (EL90). Rats were euthanized following six weeks of treatment. The left femora were used to measure the trabecular bone microarchitecture using micro-CT. Orchidectomy significantly decreased connectivity density, trabecular bone volume, and trabecular number compared to the SHAM group. Testosterone replacement reversed all the orchidectomy-induced changes in the micro-CT parameters. EL at 30 and 60 mg/kg rat worsened the trabecular bone connectivity density and trabecular separation parameters of orchidectomised rats. EL at 90 mg/kg rat preserved the bone volume. High dose of EL (90 mg/kg) may have potential in preserving the bone microarchitecture of orchidectomised rats, but lower doses may further worsen the osteoporotic changes.
Arctic Climate Variability and Trends from Satellite Observations
Authors: Wang Xuanji , Key Jeffrey , Liu Yinghui , Fowler Charles , Maslanik James , Tschudi Mark
Published: August 2012

Arctic climate has been changing rapidly since the 1980s. This work shows distinctly different patterns of change in winter, spring, and summer for cloud fraction and surface temperature. Satellite observations over 1982–2004 have shown that the Arctic has warmed up and become cloudier in spring and summer, but cooled down and become less cloudy in winter. The annual mean surface temperature has increased at a rate of 0.34°C per decade. The decadal rates of cloud fraction trends are −3.4%, 2.3%, and 0.5% in winter, spring, and summer, respectively. Correspondingly, annually averaged surface albedo has decreased at a decadal rate of −3.2%. On the annual average, the trend of cloud forcing at the surface is −2.11 W/m2per decade, indicating a damping effect on the surface warming by clouds. The decreasing sea ice albedo and surface warming tend to modulate cloud radiative cooling effect in spring and summer. Arctic sea ice has also declined substantially with decadal rates of −8%, −5%, and −15% in sea ice extent, thickness, and volume, respectively. Significant correlations between surface temperature anomalies and climate indices, especially the Arctic Oscillation (AO) index, exist over some areas, implying linkages between global climate change and Arctic climate change.
A Design Method of Saturation Test Image Based on CIEDE2000
Authors: Yang Yang , Ming Jun , Yu Nenghai
Published: August 2012

In order to generate color test image consistent with human perception in aspect of saturation, lightness, and hue of image, we propose a saturation test image design method based on CIEDE2000 color difference formula. This method exploits the subjective saturation parameterC′ of CIEDE2000 to get a series of test images with different saturation but same lightness and hue. It is found experimentally that the vision perception has linear relationship with the saturation parameterC′. This kind of saturation test image has various applications, such as in the checking of color masking effect in visual experiments and the testing of the visual effects of image similarity component.
Hydrolysis of Virgin Coconut Oil Using Immobilized Lipase in a Batch Reactor
Authors: Chua Lee Suan , Alitabarimansor Meisam , Lee Chew Tin , Mat Ramli
Published: August 2012

Hydrolysis of virgin coconut oil (VCO) had been carried out by using an immobilised lipase from Mucor miehei (Lipozyme) in a water-jacketed batch reactor. The kinetic of the hydrolysis was investigated by varying the parameters such as VCO concentration, enzyme loading, water content, and reaction temperature. It was found that VCO exhibited substrate inhibition at the concentration more than 40% (v/v). Lipozyme also achieved the highest production of free fatty acids, 4.56 mM at 1% (w/v) of enzyme loading. The optimum water content for VCO hydrolysis was 7% (v/v). A relatively high content of water was required because water was one of the reactants in the hydrolysis. The progress curve and the temperature profile of the enzymatic hydrolysis also showed that Lipozyme could be used for free fatty acid production at the temperature up to 50°C. However, the highest initial reaction rate and the highest yield of free fatty acid production were at 45 and 40°C, respectively. A 100 hours of initial reaction time has to be compensated in order to obtain the highest yield of free fatty acid production at 40°C.
Human Embryonic Stem Cell Responses to Ionizing Radiation Exposures: Current State of Knowledge and Future Challenges
Authors: Sokolov Mykyta V. , Neumann Ronald D.
Published: August 2012

Human embryonic stem cells, which are derived from the inner cell mass of the blastocyst, have become an object of intense study over the last decade. They possess two unique properties that distinguish them from many other cell types: (i) the ability to self-renew indefinitely in culture under permissive conditions, and (ii) the pluripotency, defined as the capability of giving rise to all cell types of embryonic lineage under the guidance of the appropriate developmental cues. The focus of many recent efforts has been on the elucidating the signaling pathways and molecular networks operating in human embryonic stem cells. These cells hold great promise in cell-based regenerative therapies, disease modeling, drug screening and testing, assessing genotoxic and mutagenic risks associated with exposures to a variety of environmental factors, and so forth. Ionizing radiation is ubiquitous in nature, and it is widely used in diagnostic and therapeutic procedures in medicine. In this paper, our goal is to summarize the recent progress in understanding how human embryonic stem cells respond to ionizing radiation exposures, using novel methodologies based on “omics” approaches, and to provide a critical discussion of what remains unknown; thus proposing a roadmap for the future research in this area.