bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF TEMPERATURE AND RELATIVE HUMIDITY ON GROWTH BEHAVIOR OF ESCHERICHIA COLI O157:H7 ON SPINACH USING RESPONSE SURFACE METHODOLOGY
Authors: WANG JUN , OH DEOG‐HWAN
Published: June 2012

In this study, response surface methodology (RSM) was used to model the growth of Escherichia coli O157:H7 on spinach as a function of temperature (15–35C) and relative humidity (60–80%). The growth data were collected under different conditions, and were then fitted by the modified Gompertz model to estimate the maximum growth rate (GR), lag time (LT) and maximum population density (MPD) at each condition with high coefficients of determination (R2 > 0.98). Moreover, the secondary models were developed for the GR, LT and MPD values obtained from the primary model using RSM quadratic polynomial equation. Model validation was conducted based on the additional experimental data not used for the model development. The results showed that the overall predictions had slight deviation with the observations for its acceptable ranges of bias and accuracy factors as well as lower standard errors of predictions, indicating success at predicting the growth of E. coli O157:H7 on spinach.

PRACTICAL APPLICATIONS

The impact of environmental factors including temperature and relative humidity on the response of Escherichia coli O157:H7 on spinach were investigated using response surface methodology. The methodology was successfully applied to E. coli O157:H7 on spinach and the developed models based on the experimental data at simulated conditions exhibited a satisfactory performance. The model developed in this study could be applied during the vegetable distribution chain from farm to retail to predict the growth of E. coli O157:H7 and provide sufficient information for the development of microbiological risk assessment related to E. coli O157:H7 on spinach.
The practical implications of TARGET for adenoidectomy in children with otitis media with effusion
Authors: James A.L.
Published: June 2012

Clin. Otolaryngol. 2012, 37, 174–175
12 minute consultation: Evidence based management of a patient with facial pain
Authors: T. Kamani , N.S. Jones
Published: June 2012

Clin. Otolaryngol. 2012, 37, 207–212

Background:  There is a common misconception that facial pain and headache are mainly caused by sinusitis. The findings of nasal endoscopy, computer tomography (CT) and the results of observational studies reveal that this is not the case. Moreover, when sinus surgery is performed in patients where headache/facial pain has been a feature, it has been found that these symptoms persist after sinus surgery, particularly where there had been no nasal symptoms or endoscopic signs of paranasal sinusitis.

Methods:  This review was based on a literature search performed on 30 November 2011. The MEDLINE, EMBASE and Cochrane databases were searched using the subject heading of facial pain, that is, rhinosinusitis, migraine, cluster headaches, midsegment facial pain, trigeminal neuralgia, paroxysmal hemicrania, hemicrania continua and drug‐dependent headache. The search was limited to English language articles. Relevant references from selected articles were reviewed after reading the abstract.

Results:  A review of the literature shows that headaches are rarely caused by sinusitis. Similarly, only a small proportion of patients with facial pain have sinusitis, and these patients have either acute sinusitis or an acute exacerbation of chronic purulent sinusitis. Importantly, most patients with chronic rhinosinusitis rarely have facial pain unless they develop an acute infection or suffer barotrauma. CT scans should not routinely be performed for facial pain because of the prevalence of incidental changes in asymptomatic patients. Surgery is very rarely indicated in the treatment for chronic facial pain.

Conclusion:  A structured history of the pain and its associated symptoms, nasendoscopy and relevant targeted investigations should lead to a correct diagnosis and the appropriate treatment.
Updating a Cochrane review of endoscopic balloon dilation for chronic rhinosinusitis: A randomised controlled trial that is biased in its reporting
Authors: Browning G.G.
Published: June 2012

Clin. Otolaryngol. 2012, 37, 222
Choosing the rules for consensus standardization
Authors: Farrell Joseph , Simcoe Timothy
Published: June 2012

Consensus standardization often involves bargaining without side payments or substantive compromise, creating a war of attrition that selects through delay. We investigate the trade‐off between screening and delay when this process selects for socially valuable but privately observed quality. Immediate random choice may outperform the war of attrition, or vice versa. Allowing an uninformed neutral player to break deadlocks can improve on both mechanisms. Policies that reduce players’ vested interest, and hence delays, can strengthen the ex ante incentive to improve proposals.
An approximate dynamic programming approach to solving dynamic oligopoly models
Authors: Farias Vivek , Saure Denis , Weintraub Gabriel Y.
Published: June 2012

In this article, we introduce a new method to approximate Markov perfect equilibrium in large‐scale Ericson and Pakes (1995)‐style dynamic oligopoly models that are not amenable to exact solution due to the curse of dimensionality. The method is based on an algorithm that iterates an approximate best response operator using an approximate dynamic programming approach. The method, based on mathematical programming, approximates the value function with a linear combination of basis functions. We provide results that lend theoretical support to our approach. We introduce a rich yet tractable set of basis functions, and test our method on important classes of models. Our results suggest that the approach we propose significantly expands the set of dynamic oligopoly models that can be analyzed computationally.
Mitochondrial activation at the onset of contractions in isolated myofibres during successive contractile periods
Authors: Gandra Paulo G. , Nogueira Leonardo , Hogan Michael C.
Published: June 2012

Key points

During the transition in skeletal muscle from rest to steady state contractions, O2 consumption is limited and the exact mechanisms controlling respiration in intact cells are not completely understood.

Previous contractile activity can ‘prime’ skeletal muscle resulting in a faster enhancement of the O2 consumption during a subsequent bout of contractions.

Here, we showed in intact single muscle fibres that the mitochondrial electron transport chain was activated faster at the onset of contractions when the muscle cells were previously ‘primed’ by contractile activity.

Therefore, factors intrinsic to the muscle cells have a role in the delayed increase of mitochondrial respiration during the onset of contractions. Also, the control of mitochondrial respiration in intact cells is not simply dependent on substrate availability or a simple feedback mechanism but rather on a more complex system.

Abstract  At the onset of skeletal muscle repetitive contractions, there is a significant delay in the time to achieve oxidative phosphorylation steady state. The purpose of the present study was to examine the factors that limit oxidative phosphorylation at the onset of contractions. NAD(P)H was measured in real time during two contractile periods (2 min each) separated by 5 min of rest in intact single muscle fibres (n= 7) isolated from Xenopus laevis. The fibres were then loaded with the dye tetramethylrhodamine methyl ester perchlorate (TMRM) to evaluate the kinetics of the mitochondrial membrane potential (Δψm) during two further successive contractile periods. At the onset of contractions in the first period, NAD(P)H exhibited a time delay (14.1 ± 1.3 s) before decreasing toward a steady state. In contrast, Δψm decreased immediately after the first contraction and started to be reestablished after 10.7 ± 0.9 s, with restoration to the pre‐stimulation values after approximately 32 s. In the second contractile period (5 min after the first), NAD(P)H decreased immediately (i.e. no time delay) after the first contraction and had a significantly shorter time constant compared to the first contractile bout (3.3 ± 0.3 vs. 5.0 ± 0.2 s, P < 0.05). During the second bout, Δψm remained unchanged from pre‐stimulation values. These results suggest: (1) that at the onset of contractions, oxidative phosphorylation is primarily limited by the activity of the electron transport chain complexes rather than by a limited level of substrates; and (2) when the muscle is ‘primed’ by previous contractile activity, the faster enhancement of the cellular respiratory rate is due to intrinsic factors within the myofibre.
Aerodynamic Improvements of Wind-Turbine Airfoil Geometries With the Prescribed Surface Curvature Distribution Blade Design (CIRCLE) Method
Authors: Korakianitis T. , Rezaienia M. A. , Hamakhan I. A. , Avital E. J. , Williams J. J. R.
Published: June 2012

The prescribed surface curvature distribution blade design (CIRCLE) method can be used for the design of two-dimensional (2D) and three-dimensional (3D) turbomachinery blade rows with continuous curvature and slope of curvature from leading edge (LE) stagnation point to trailing edge (TE) stagnation point and back to the LE stagnation point. This feature results in smooth surface pressure distribution airfoils with inherently good aerodynamic performance. In this paper the CIRCLE blade design method is modified for the design of 2D isolated airfoils. As an illustration of the capabilities of the method, it is applied to the redesign of two representative airfoils used in wind turbine blades: the Eppler 387 airfoil and the NREL S814 airfoil. Computational fluid dynamic analysis is used to investigate the design point and off-design performance of the original and modified airfoils, and compare with experiments on the original ones. The computed aerodynamic advantages of the modified airfoils are discussed. The surface pressure distributions, drag coefficients, and lift-to-drag coefficients of the original and redesigned airfoils are examined. It is concluded that the method can be used for the design of wind turbine blade geometries of superior aerodynamic performance.
Dynamic Model for Understanding Spatial Temperature and Species Distributions in Internal-Reforming Solid Oxide Fuel Cells
Authors: Shaffer Brendan , Brouwer Jacob
Published: June 2012

Direct internal reformation of methane in solid oxide fuel cells (SOFCs) leads to two major performance and longevity challenges: thermal stresses in the cell due to large temperature gradients and coke formation on the anode. A simplified quasi-two-dimensional direct internal reformation SOFC (DIR-SOFC) dynamic model was developed for investigation of the effects of various parameters and assumptions on the temperature gradients across the cell. The model consists of 64 nodes, each containing four control volumes: the positive electrode, electrolyte, negative electrode (PEN), interconnect, anode gas, and cathode gas. Within each node the corresponding conservation and chemical and electrochemical reaction rate equations are solved. The model simulates the counter-flow configuration since previous research (Achenbach, 1994, “Three-Dimensional and Time-Dependent Simulation of a Planar Solid Oxide Fuel Cell Stack,” J. Power Sources, 49(1), p. 333) has shown this configuration to yield the smallest temperature differentials for DIR-SOFCs. Steady state simulations revealed several results where the temperature difference across the cell was considerably affected by operating conditions and cell design parameters. Increasing the performance of the cell through modifications to the electrochemical model to simulate modern cell performance produced significant changes in the cell temperature differential. Improved cell performance led to a maximum increase in the temperature differential across the cell of 31 K. An increase in the interconnect thickness from 3.5 to 4.5 mm was shown to reduce the PEN temperature difference about 50 K. Variation of other physical parameters such as the thermal conductivity of the interconnect and the rib width also showed significant effects on the temperature distribution. The sensitivity of temperature distribution to heat losses was also studied, showing a considerable effect near the fuel and air inlets. Increased heat transfer from the cell edges resulted in severe temperature gradients approaching 160 K/cm. The dynamic capability of the spatially resolved dynamic model was also demonstrated for a 45% power increase perturbation while maintaining constant fuel and air utilizations.
Oxygen Transport Membranes for Ultra-Supercritical (USC) Power Plants With Very Low CO2 Emissions
Authors: Gambini Marco , Vellini Michela
Published: June 2012

Coal combustion for electric power generation is one of the major contributors to anthropogenic CO2 emissions to the atmosphere. Carbon capture and storage (CCS) technologies are currently intensively investigated in order to mitigate CO2 emissions. The technique which is currently the most pursued is post combustion scrubbing of the flue gas, due to the potential to retrofit post combustion capture to existing power plants. However, it also comes with a substantial energy penalty. To reduce the energy demand of CO2 processing, the so-called oxyfuel technology presents an option to increase the concentration of CO2 in the flue gas. Here, the coal is burned in a mixture of oxygen and recycled flue gas. Hence, the flue gas primarily consists of CO2 and water vapor, which can be easily condensed. In general, there are two different techniques for oxygen production in oxyfuel power plants: cryogenic air separation (it is a method which can be easily implemented since it is already well established in industry) and a mixed metal oxide ceramic membrane (ITM or OTM) operating at high temperatures (it is a new process for O2 production, which is under development). In the last ten years, efforts in the efficient utilization of energy and reduction of emissions have indirectly stimulated research in mixed conducting membranes. In fact, the presently available cryogenic air separation process consumes a significant fraction of the generating plant’s output and reduces its efficiency. Oxygen transport membrane (OTM) integration with an ultra-supercritical (USC) power plant is, indeed, considered a promising technology that will lead to economic and energy savings compared to the previous solution. In this paper, we discuss the actual potentialities and limits of OTM and their integration in USC power plants.
Propulsive Performance of Ideal Detonation Turbine Based Combined Cycle Engine
Authors: Qiu Hua , Xiong Cha , Yan Chuan-jun , Fan Wei
Published: June 2012

A novel two-mode propulsion system based on detonation combustion, known as a detonation turbine based combined cycle engine (DTBCC), was proposed and thermodynamically analyzed for potential application to aircrafts whose flight Mach number is from 0 to 5. The obvious advantage of the two-mode system is that both modes share the same multidetonation chambers. The quasi-stable total temperature and total pressure for inlet conditions of the turbine could be realized in this hybrid pulse detonation engine. A key parameter (drive area ratio) was defined as the ratio of the outflow area at the head to the cross-sectional area of the detonation chamber. The calculated results showed that the increase of the drive area ratio led to the increase in the mass flow entering the turbine; however, this led to the decrease of the total inlet temperature, the total inlet pressure, and the expansion-pressure ratio of the turbine. Compared with an ideal turbojet engine, the inlet temperature of the turbine in a preturbine hybrid pulse detonation engine with a drive area ratio of 1 was 80 K lower than the former under the same pressure ratio and the same fuel-air ratio. In other words, the increase of the drive area ratio may improve the performance of this hybrid pulse detonation engine. Variation of the pressure ratio was adapted to varied flight Mach numbers by a change of the drive area ratio, which induced the enlargement of the operating range. Finally, a performance model was established to research the components’ characteristics and the propulsive performance of the engine. Preliminary performance estimates suggested that thrust and specific fuel consumption of the two-mode propulsion system were superior to the existing turbine based combined cycle designs.
Performance Improvement of a Circular MCFC Through Optimal Design of the Fluid Distribution System
Authors: Sciacovelli Adriano , Verda Vittorio , Amelio Cristina , Repetto Carlo , Diaz Gustavo
Published: June 2012

In this paper, the prototype of a circular molten carbonate fuel cell (MCFC) built in the laboratories of FN SpA Nuove Tecnologie e Servizi Avanzati is analyzed using a tridimensional computational fluid dynamic (CFD) model. The prototype is the result of FN and Politecnico di Torino activities developed for the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) within the framework of Ministry of Economic Development, MSE-ENEA. This model considers heat, mass and current transfer as well as chemical and electrochemical reactions. The results show that some inhomogeneous distributions in the reactants, causing nonoptimal use of the reactant surfaces. An effective way to improve the distribution in current density consists in tracing tree shaped channels on the surface onto the distribution porous medium. In this paper, Y shaped channels are adopted to improve the distribution of gas within the fuel cell and consequently to enhance the performance of the original design of the fuel cell. In addition, the configuration of the outlet of the anodic compartment is also investigated in order to further increase the performance of the fuel cell. The geometrical parameter identifying the topology of distribution channels are chosen accordingly to the constructal theory. The results show that significant improvements can be achieved. Power density is increased of about 6% when the tree-shaped channel is adopted. If a double anodic inlet is also considered, the enhancement in the power density is of about 11% with respect to the initial configuration.
Direct Modification and Activation of a Nuclear Receptor–PIP
2
Complex by the Inositol Lipid Kinase IPMK
Authors: Blind Raymond D. , Suzawa Miyuki , Ingraham Holly A.
Published: June 2012

The transcriptional activity of a nuclear receptor is regulated by the phosphorylation status of a bound lipid.
How Growth Abnormalities Delay “Puberty” in
Drosophila
Authors: Hariharan Iswar K.
Published: June 2012

An insulin-like peptide delays metamorphosis of the fruit fly in response to injury or tissue overgrowth.
Persistence of Transferable Extended-Spectrum-β-Lactamase Resistance in the Absence of Antibiotic Pressure
Authors: Cottell Jennifer L. , Webber Mark A. , Piddock Laura J. V.
Published: June 2012

The treatment of infections caused by antibiotic-resistant bacteria is one of the great challenges faced by clinicians in the 21st century. Antibiotic resistance genes are often transferred between bacteria by mobile genetic vectors called plasmids. It is commonly believed that removal of antibiotic pressure will reduce the numbers of antibiotic-resistant bacteria due to the perception that carriage of resistance imposes a fitness cost on the bacterium. This study investigated the ability of the plasmid pCT, a globally distributed plasmid that carries an extended-spectrum-β-lactamase (ESBL) resistance gene (
bla
CTX-M-14
), to persist and disseminate in the absence of antibiotic pressure. We investigated key attributes in plasmid success, including conjugation frequencies, bacterial-host growth rates, ability to cause infection, and impact on the fitness of host strains. We also determined the contribution of the
bla
CTX-M-14
gene itself to the biology of the plasmid and host bacterium. Carriage of pCT was found to impose no detectable fitness cost on various bacterial hosts. An absence of antibiotic pressure and inactivation of the antibiotic resistance gene also had no effect on plasmid persistence, conjugation frequency, or bacterial-host biology. In conclusion, plasmids such as pCT have evolved to impose little impact on host strains. Therefore, the persistence of antibiotic resistance genes and their vectors is to be expected in the absence of antibiotic selective pressure regardless of antibiotic stewardship. Other means to reduce plasmid stability are needed to prevent the persistence of these vectors and the antibiotic resistance genes they carry.
Azole Preexposure Affects the Aspergillus fumigatus Population in Patients
Authors: Alanio Alexandre , Cabaret Odile , Sitterlé Emilie , Costa Jean-Marc , Brisse Sylvain , Cordonnier Catherine , Bretagne Stéphane
Published: June 2012

The relationship between the azole preexposure of 86 patients and the genotype, azole susceptibility, and
cyp51A
polymorphisms of 110 corresponding
Aspergillus fumigatus
isolates was explored. Isolates carrying serial polymorphisms (F46Y and M172V with or without N248T with or without D255E with or without E427K) had higher itraconazole MICs (
P
= 0.04), although <2 μg/ml using the EUCAST methodology, were associated with two genetic clusters (
P
< 0.001) and with voriconazole preexposure of patients (
P
= 0.016). Voriconazole preexposure influences the distribution of
A. fumigatus
isolates with selection of isolates carrying
cyp51A
polymorphisms and higher itraconazole MICs.
Macrophage Autophagy in Immunity to Cryptococcus neoformans and Candida albicans
Authors: Nicola André Moraes , Albuquerque Patrícia , Martinez Luis R. , Dal-Rosso Rafael Antonio , Saylor Carolyn , De Jesus Magdia , Nosanchuk Joshua D. , Casadevall Arturo
Published: June 2012

Autophagy is used by eukaryotes in bulk cellular material recycling and in immunity to intracellular pathogens. We evaluated the role of macrophage autophagy in the response toCryptococcus neoformansandCandida albicans, two important opportunistic fungal pathogens. The autophagosome marker LC3 (microtubule-associated protein 1 light chain 3 alpha) was present in most macrophage vacuoles containingC. albicans. In contrast, LC3 was found in only a few vacuoles containingC. neoformanspreviously opsonized with antibody but never after complement-mediated phagocytosis. Disruption of host autophagyin vitroby RNA interference against ATG5 (autophagy-related 5) decreased the phagocytosis ofC. albicansand the fungistatic activity of J774.16 macrophage-like cells against both fungi, independent of the opsonin used. ATG5-knockout bone marrow-derived macrophages (BMMs) also had decreased fungistatic activity againstC. neoformanswhen activated. In contrast, nonactivated ATG5-knockout BMMs actually restrictedC. neoformansgrowth more efficiently, suggesting that macrophage autophagy plays different roles againstC. neoformans, depending on the macrophage type and activation. Interference with autophagy in J774.16 cells also decreased nonlytic exocytosis ofC. neoformans, increased interleukin-6 secretion, and decreased gamma interferon-induced protein 10 secretion. Mice with a conditionally knocked out ATG5 gene in myeloid cells showed increased susceptibility to intravenousC. albicansinfection. In contrast, these mice manifested no increased susceptibility toC. neoformans, as measured by survival, but had fewer alternatively activated macrophages and less inflammation in the lungs after intratracheal infection than control mice. These results demonstrate the complex roles of macrophage autophagy in restricting intracellular parasitism by fungi and reveal connections with nonlytic exocytosis, humoral immunity, and cytokine signaling.
Trends in social inequalities for premature coronary heart disease mortality in Great Britain, 1994–2008: a time trend ecological study
Authors: McCartney David , Scarborough Peter , Webster Premila , Rayner Mike
Published: June 2012

Objective

To compare trends in metrics of socioeconomic inequalities in premature coronary heart disease (CHD) mortality in Great Britain.

Design

Time trend ecological study with area-level deprivation as exposure.

Setting

Great Britain, 1994–2008.

Participants

Men and women aged younger than 75 years. No lower age limit.

Interventions

None.

Main outcome measures

CHD mortality rates.

Results

There has been a decrease in socioeconomic inequalities in CHD mortality in absolute terms but an increase in relative terms. CHD mortality rates in men aged younger than 75 years fell by 69 per 100 000 (95% CIs 64 to 74) in the least deprived quintile and by 92 per 100 000 (95% CI 86 to 98) in the most deprived quintile (p for trend: <0.001). Mortality rate ratios comparing the most deprived quintile to the least deprived quintile increased in women aged younger than 75 years from 1.77 (95% CI 1.68 to 1.86) to 2.32 (95% CI 2.14 to 2.52). There was a weak negative association between the average decline of relative rates and area deprivation.

Conclusions

It could either be said that inequalities in premature mortality from CHD between affluent and deprived areas have widened or narrowed between 1994 and 2008 depending on the measurement technique. In the context of falling CHD mortality rates, narrowing of absolute inequalities is to be expected, but increases in relative inequalities are a cause for concern.
A descriptive epidemiological study on the patterns of occupational injuries in a coastal area and a mountain area in Southern China
Authors: Li Liping , Liu Xiaojian , Choi Bernard C K , Lu Yaogui , Yu Min
Published: June 2012

Objectives

This study compared patterns of occupational injuries in two different areas, coastal (industrial) and mountain (agricultural), in Southern China to provide information for development of occupational injury prevention measures in China.

Design

Descriptive epidemiological study.

Setting

Data were obtained from the Hospital Injury Surveillance System based on hospital data collected from 1 April 2006 to 31 March 2008.

Participants

Cases of occupational injury, defined as injury that occurred when the activity indicated was work.

Outcome measures

Distribution and differences of patterns of occupational injuries between the two areas.

Results

Men were more likely than women to experience occupational injuries, and there was no difference in the two areas (p=0.112). In the coastal area, occupational injury occurred more in the 21–30-year age group, but in the mountain area, it was the 41–50-year age group (p<0.001). Occupational injuries in the two areas differed by location of hometown, education and occupation (all p<0.001). Occupational injuries peaked differently in the month of the year in the two areas (p<0.001). Industrial and construction areas were the most frequent locations where occupational injuries occurred (p<0.001). Most occupational injuries were unintentional and not serious, and patients could go home after treatment. The two areas also differed in external causes and consequences of occupational injuries.

Conclusions

The differing patterns of occupational injuries in the coastal and mountain areas in Southern China suggest that different preventive measures should be developed. Results are relevant to other developing countries that have industrial and agricultural areas.
GENERALIZED HOLOGRAPHIC DARK ENERGY AND ITS OBSERVATIONAL CONSTRAINTS
Authors: ZHANG ZHENHUI , LI MIAO , LI XIAO-DONG , WANG SHUANG , ZHANG WEN-SHUAI
Published: June 2012

In the original holographic dark energy (HDE) model, the dark energy density is proposed to be [Formula: see text], with c a dimensionless constant characterizing the properties of the HDE. In this work, we propose the generalized holographic dark energy (GHDE) model by considering the parameter c as a redshift-dependent function c(z). We derive all the physical quantities of the GHDE model analytically, and fit the c(z) by trying four kinds of parametrizations. The cosmological constraints of the c(z) are obtained from the joint analysis of the present SNLS3+BAO+CMB +H0data. We find that, compared with the original HDE model, the GHDE models can provide a better fit to the data. For example, the GHDE model with JBP-type c(z) can reduce the [Formula: see text] of the HDE model by 2.16. We also find that, unlike the original HDE model with a phantom-like behavior in the future, the GHDE models can present many more different possibilities, i.e. it allows the GHDE in the future to be either quintessence-like, cosmological constant-like, or phantom-like, depending on the forms of c(z).
GUEST EDITOR'S INTRODUCTION
Authors: HARRINGTON BRIAN
Published: June 2012

No abstract recevied.
A KNOWLEDGE REPRESENTATION LANGUAGE FOR NATURAL LANGUAGE PROCESSING, SIMULATION AND REASONING
Authors: McSHANE MARJORIE , NIRENBURG SERGEI
Published: June 2012

OntoAgent is an environment that supports the cognitive modeling of societies of intelligent agents that emulate human beings. Like traditional intelligent agents, OntoAgent agents execute the core functionalities of perception, reasoning and action. Unlike most traditional agents, they engage in extensive "translation" functions in order to render perceived inputs into the unambiguous, ontologically-grounded knowledge representation language (KRL) that is used to model their knowledge, memory and reasoning. This paper describes the KRL of OntoAgent with a special focus on the many runtime functions used to translate between perceived inputs and the KRL, as well as to manipulate KRL structures for reasoning and simulation.
A NEW PROOF FOR ZASSENHAUS–GROEMER–OLER INEQUALITY
Authors: LIU QINGHAI , LI XIANG , WU LIDONG , DU HAI , ZHANG ZHAO , WU WEILI , HU XIAODONG , XU YINFENG
Published: June 2012

In this paper, we present a new proof for a well-known inequality, conjectured by Zassenhaus in 1947 and proved independently by Groemer in 1960 and Oler in 1961. The inequality gives an upper bound for the number of nonoverlapping unit discs whose centers can be packed into a compact convex region, and recently obtains a lot of applications in study of sensor networks.
AN EFFICIENT ALGORITHM FOR DERIVING SUMMATION IDENTITIES FROM MUTUAL RECURRENCES
Authors: CHURCHILL BERKELEY R. , LAMAGNA EDMUND A.
Published: June 2012

This paper closes an algorithmic problem of summing a set of mutual recurrence relations with constant coefficients. Given an order d system of the form [Formula: see text], where A, G : ℕ → Km and M1,…, Md ∈ Mm(K) for some field K and natural number m, this algorithm computes the sum [Formula: see text] as a K-linear combination of A(n),…, A(n - d), the initial conditions and sums of the inhomogeneous term G(n). The runtime of this algorithm is shown to be polynomial in m and d.
YAO GRAPHS SPAN THETA GRAPHS
Authors: DAMIAN MIRELA , RAUDONIS KRISTIN
Published: June 2012

Yao and Theta graphs are defined for a given point set and a fixed integer k > 0. The space around each point is divided into k cones of equal angle, and each point is connected to a nearest neighbor in each cone. The difference between Yao and Theta graphs is in the way the nearest neighbor is defined: Yao graphs minimize the Euclidean distance between a point and its neighbor, and Theta graphs minimize the Euclidean distance between a point and the orthogonal projection of its neighbor on the bisector of the hosting cone. We prove that, corresponding to each edge of the Theta graph Θ6, there is a path in the Yao graph Y6 whose length is at most 8.82 times the edge length. Combined with the result of Bonichon et al., who prove an upper bound of 2 on the stretch factor of Θ6, we obtain an upper bound of 17.64 on the stretch factor of Y6.
PHASE FIELD STUDY OF POLARIZATION VORTEX IN FERROELECTRIC NANOSTRUCTURES
Authors: WANG JIE , ZHANG TONG-YI
Published: June 2012

Ferroelectric nanostructures are attracting considerable attention due to their unusual physical properties and potential applications in memory devices and nanoelectromechanical systems. It has been found that low-dimensional ferroelectrics, such as ferroelectric nanodots, ferroelectric nanotubes and ferroelectric thin films, exhibit polarization vortices or vortex-like domain structures due to the strong depolarization field and the size effect. The polarization vortex is regarded as a new toroidal order in ferroelectrics which is different from the rectilinear order of polarization. The vortex states of polarization are bistable and can be switched from one state to the other, which holds the potential application in next generation ferroelectric memories. This paper briefly reviews the recent work on the phase field studies of polarization vortex in ferroelectric nanostructures. The homogeneous bulk thermodynamics of ferroelectrics is first introduced based on the Landau–Devonshire theory. To describe the inhomogeneous polarization distribution in ferroelectrics, the phase field model including interface thermodynamics is then presented in the form of time-dependent Ginzburg–Landau equations.
POLAR STRUCTURES OF PbMg1/3Nb2/3O3-PbTiO3 RELAXORS: PIEZORESPONSE FORCE MICROSCOPY APPROACH
Authors: SHVARTSMAN V. V. , KHOLKIN A. L.
Published: June 2012

Relaxor ferroelectrics are one of the mysterious objects of the solid-state physics studied over 50 years. The physical properties of relaxors were mainly assessed by scattering and dielectric methods and revealed the importance of polarization correlations with the short-range order, so-called polarization nanoscale regions. This paper review recent progress achieved by using piezoresponse force microscopy (PFM) to analyze the spatial distribution of polarization and its evolution with time, temperature, and electric field for the most popular relaxor family: solid solutions between PbMg1/3Nb2/3O3 and PbTiO3 . The PFM technique has proved to be a powerful tool for the investigation of local properties of relaxors where optical techniques obviously fail because of their lack of resolution. The PFM study of relaxors clearly helps to understand the mechanism of polarization distribution and illustrates the importance of mesoscopic polarization patterns that were until now overlooked by major theories of the relaxor state.
DIELECTRIC RELAXATION IN RELAXOR FERROELECTRICS
Authors: BOKOV ALEXEI A. , YE ZUO-GUANG
Published: June 2012

In this review the dielectric properties of relaxor ferroelectrics are discussed and compared with the properties of normal dielectrics and ferroelectrics. We try to draw a general picture of dielectric relaxation starting from a textbook review of the underlying concepts and pay attention to common behavior of relaxors rather than to the features observed in specific materials. We hope that this general approach is beneficial to those physicists, chemists, material scientists and device engineers who deal with relaxors. Based on the analysis of dielectric properties, a comprehensive definition of relaxors is proposed: relaxors are defined as ferroelectrics in which the maximum in the temperature dependence of static susceptibility occurs within the temperature range of dielectric relaxation, but does not coincide with the temperature of singularity of relaxation time or soft mode frequency.
Chemical Sensing with Nanowires
Authors: Penner Reginald M.
Published: June 2012

Transformational advances in the performance of nanowire-based chemical sensors and biosensors have been achieved over the past two to three years. These advances have arisen from a better understanding of the mechanisms of transduction operating in these devices, innovations in nanowire fabrication, and improved methods for incorporating receptors into or onto nanowires. Nanowire-based biosensors have detected DNA in undiluted physiological saline. For silicon nanowire nucleic acid sensors, higher sensitivities have been obtained by eliminating the passivating oxide layer on the nanowire surface and by substituting uncharged protein nucleic acids for DNA as the capture strands. Biosensors for peptide and protein cancer markers, based on both semiconductor nanowires and nanowires of conductive polymers, have detected these targets at physiologically relevant concentrations in both blood plasma and whole blood. Nanowire chemical sensors have also detected several gases at the parts-per-million level. This review discusses these and other recent advances, concentrating on work published in the past three years.
Computational Models of Protein Kinematics and Dynamics: Beyond Simulation
Authors: Gipson Bryant , Hsu David , Kavraki Lydia E. , Latombe Jean-Claude
Published: June 2012

Physics-based simulation represents a powerful method for investigating the time-varying behavior of dynamic protein systems at high spatial and temporal resolution. Such simulations, however, can be prohibitively difficult or lengthy for large proteins or when probing the lower-resolution, long-timescale behaviors of proteins generally. Importantly, not all questions about a protein system require full space and time resolution to produce an informative answer. For instance, by avoiding the simulation of uncorrelated, high-frequency atomic movements, a larger, domain-level picture of protein dynamics can be revealed. The purpose of this review is to highlight the growing body of complementary work that goes beyond simulation. In particular, this review focuses on methods that address kinematics and dynamics, as well as those that address larger organizational questions and can quickly yield useful information about the long-timescale behavior of a protein.
Redox-Responsive Delivery Systems
Authors: McCarley Robin L.
Published: June 2012

Stimuli-responsive systems for the transport and delivery of materials to a given location at a specific time are highly valuable in numerous applications. The characteristics of the delivery system are dictated by the requirements of a particular application, which include the nature of the stimulus for actuation of the delivery process. Electron transfer has moved to the forefront as a stimulus for responsive delivery systems, particularly for those used in drug and reagent delivery, and for analyte transport/separation avenues. Interest in redox-activated delivery of materials arises from the abundance of redox-active stimuli that can be used to make delivery occur, the often simple chemical nature of the activation process, and the ease of constructing delivery vehicles with an integrated redox-responsive trigger group. This review is focused on vesicle- and micelle-based vehicles whose contents can be delivered by a redox stimulus due to their potential to meet the needs of key applications.
Situational Motivation and Perceived Intensity: Their Interaction in Predicting Changes in Positive Affect from Physical Activity
Authors: Guérin Eva , Fortier Michelle S.
Published: June 2012

There is evidence that affective experiences surrounding physical activity can contribute to the proper self-regulation of an active lifestyle. Motivation toward physical activity, as portrayed by self-determination theory, has been linked to positive affect, as has the intensity of physical activity, especially of a preferred nature. The purpose of this experimental study was to examine the interaction between situational motivation and intensity [i.e., ratings of perceived exertion (RPE)] in predicting changes in positive affect following an acute bout of preferred physical activity, namely, running. Fourty-one female runners engaged in a 30-minute self-paced treadmill run in a laboratory context. Situational motivation for running, pre- and post-running positive affect, and RPE were assessed via validated self-report questionnaires. Hierarchical regression analyses revealed a significant interaction effect between RPE and introjection (P<.05) but not between RPE and identified regulation or intrinsic motivation. At low levels of introjection, the influence of RPE on the change in positive affect was considerable, with higher RPE ratings being associated with greater increases in positive affect. The implications of the findings in light of SDT principles as well as the potential contingencies between the regulations and RPE in predicting positive affect among women are discussed.
Access and Barriers to Healthcare Vary among Three Neighboring Communities in Northern Honduras
Authors: Pearson Catherine A. , Stevens Michael P. , Sanogo Kakotan , Bearman Gonzalo M. L.
Published: June 2012

Objective. The aim of this study is to describe and compare access and barriers to health services in three proximal yet topographically distinct communities in northern Honduras served by the nonprofit organization the Honduras Outreach Medical Brigada Relief Effort (HOMBRE). Methods. Study personnel employed a 25-item questionnaire in Spanish at the point of care during HOMBRE clinics in Coyoles, Lomitas, and La Hicaca (N=220). We describe and compare the responses between sites, using Chi-squared and Fisher Exact tests. Results. Respondents in Lomitas demonstrated the greatest limitations in access and greatest barriers to care of all sites. Major limitations in access included “never” being able to obtain a blood test, obtain radiology services, and see a specialist. Major barriers were cost, distance, facility overcrowding, transportation, being too ill to go, inability to take time off work, and lack of alternate childcare. Conclusions. Despite being under the same local health authority, geographically remote Honduran communities experience greater burdens in healthcare access and barriers than neighboring communities of the same region.
Trigeminal Neuralgia due to Vertebrobasilar Dolichoectasia
Authors: Campos Wuilker Knoner , Guasti André Accioly , da Silva Benjamin Franklin , Guasti José Antonio
Published: June 2012

We presented a case of drug-resistant trigeminal neuralgia attributed to vertebrobasilar dolichoectasia, a rare condition characterized by enlargement, tortuosity, or elongation of intracranial arteries. Dolichoectatic vessels can cause dysfunction of cranial nerves through direct vascular compression. The relationships of vertebrobasilar dolichoectasia with the particularities of neurovascular conflict and images findings are discussed.
Variation in the Stabilimenta ofCyclosa fililineataHingston, 1932, andCyclosa morretesLevi, 1999 (Araneae: Araneidae), in Southeastern Brazil
Authors: Gonzaga Marcelo O. , Vasconcellos-Neto João
Published: June 2012

We investigated the characteristics of the stabilimenta constructed by two species ofCyclosa, describing the variations within and among five populations. Both species constructed stabilimenta composed entirely of silk (linear and spiral types) or of silk and debris (linear, detritus clusters and complex types). The vertical linear detritus type was the most frequent structure for adult females of both species, whereas stabilimenta consisting of detritus clusters were more frequent for juveniles ofC. morretes. The latter structures appeared to be an intermediate state towards the linear continuous type usually found in adults. The other types were rarely found, and silk stabilimenta were to be constructed only when detritus was not available. The substitution of silk by detritus indicated that both materials function as camouflage inC. morretesandC. fililineatawebs. The positions occupied by the spiders within the detritus column (and in some cases the orientation of the stabilimenta) varied markedly within populations, and the unpredictability of their location could be important in reducing the risks of predation. The hypothesis that stabilimenta constitute defensive devices was indirectly corroborated by the observation that spider’s body width and length were, respectively, strongly correlated with the width and length of the stabilimenta.
Analysis of Risk Factors for Lymph Nodal Involvement in Early Stages of Rectal Cancer: When Can Local Excision Be Considered an Appropriate Treatment? Systematic Review and Meta-Analysis of the Literature
Authors: Carrara Alessandro , Mangiola Daniela , Pertile Riccardo , Ricci Alberta , Motter Michele , Ghezzi Gianmarco , Zappalà Orazio , Ciaghi Gianni , Tirone Giuseppe
Published: June 2012

Background. Over the past ten years oncological outcomes achieved by local excision techniques (LETs) as the sole treatment for early stages of rectal cancer (ESRC) have been often disappointing. The reasons for these poor results lie mostly in the high risk of the disease's diffusion to local-regional lymph nodes even in ESRC.Aims. This study aims to find the correct indications for LET in ESRC taking into consideration clinical-pathological features of tumours that may reduce the risk of lymph node metastasis to zero.Methods. Systematic literature review and meta-analysis of casistics of ESRC treated with total mesorectal excision with the aim of identifying risk factors for nodal involvement.Results. The risk of lymph node metastasis is higher inG≥2andT≥2tumours with lymphatic and/or vascular invasion. Other features which have not yet been sufficiently investigated include female gender, TSM stage >1, presence of tumour budding and/or perineural invasion.Conclusions. Results comparable to radical surgery can be achieved by LET only in patients with T1N0G1tumours with low-risk histological features, whereas deeper or more aggressive tumours should be addressed by radical surgery (RS).
Zinc Oxide Nanoparticle Photodetector
Authors: Chang Sheng-Po , Chen Kuan-Jen
Published: June 2012

A zinc oxide (ZnO) nanoparticle photodetector was fabricated using a simple method. Under a 5 V applied bias, its dark current and photocurrent were 1.98 × 10−8 and 9.42 × 10−7 A, respectively. In other words, a photocurrent‐to‐dark‐current contrast ratio of 48 was obtained. Under incident light at a wavelength of 375 nm and a 5 V applied bias, the detector’s measured responsivity was 3.75 A/W. The transient time constants measured during the turn‐ON and turn‐OFF states were τON = 204 s and τOFF = 486 s, respectively.
Identification of HLA-A24-Restricted Novel T Cell Epitope Peptides Derived from P-Cadherin and Kinesin Family Member 20A
Authors: Osawa Ryuji , Tsunoda Takuya , Yoshimura Sachiko , Watanabe Tomohisa , Miyazawa Motoki , Tani Masaji , Takeda Kazuyoshi , Nakagawa Hidewaki , Nakamura Yusuke , Yamaue Hiroki
Published: June 2012

We here identified human leukocyte antigen-(HLA-)A∗2402-restricted epitope peptides from Cadherin 3, type 1, P-cadherin (CDH3) and kinesin family member 20A (KIF20A) that were found to be specifically expressed in cancer cells through genome-wide expression profile analysis. CDH3-10-807 peptide and KIF20A-10-66 peptide successfully induced specific CTL clones, and these selectively responded to COS7 cells expressing both HLA-A∗2402 and respective protein while did not respond to parental cells or COS7 cells expressing either HLA-A∗2402 or respective protein. Furthermore, CTL clones responded to cancer cells that endogenously express HLA-A∗2402 and respective protein, suggesting that CDH3-10-807 peptide and KIF20A-10-66 peptide are naturally presented on HLA-A∗2402 molecule of human cancer cells. Our results demonstrated that CDH3-10-807 peptide and KIF20A-10-66 peptide are novel HLA-A24-restricted tumor-associated antigens and would be applicable for CTL-inducing cancer therapies.
Human-Bird Conflicts and Management Issues: A Case Study of Birds at Uppalapadu Lake, Andhra Pradesh, India
Authors: Prasad P. Rama Chandra , Kumari J. Asha , Mathew Manju , Thomas Rosina
Published: June 2012

The current research focused on the issues related to human-bird conflicts and subsequent alternatives adopted by the migratory birds at Uppalapadu Lake (India). The study collates the information from field observations and literature surveys and draws conclusions based on the observation data. The study highlights the ways the local community, Forest Department, activist groups and other organizations participate in protecting the birds from harm. It also focuses on some of the management initiatives taken by the Forest Department that are helping the birds during their breeding periods. Overall, the research identifies the ecological importance of the lake with respect to birds and stresses the need for its protection and further expansion.