bluuebunny/crossref_metadata_2025 huggingface dataset:
Immigration policy and market institutions in liberal market economies
Authors: Wright Chris F.
Published: March 2012

This article examines how the regulatory character of market institutions shapes government responses to labour shortages, with particular reference to immigration policy. The period between the late 1990s and the late 2000s saw many advanced economies relax entry controls on select categories of foreign workers. This trend was most pronounced among states with liberal market institutions. The underlying reasons for these trends are analysed through an examination of the motivations for reform in Australia and the UK, two states that oversaw significant liberalisations of their labour immigration policies. It argues that the liberal character of key market institutions encouraged firms in these states to look to external rather than internal solutions for meeting their labour requirements. These findings suggest that perspectives from the comparative political economy scholarship, most notably the varieties of capitalism literature, may provide insights into the way that different modes of market regulation shape immigration policy preferences.
Chlamydia trachomatis, Mycoplasma genitalium and Ureaplasma urealyticum among students in northern Norway
Authors: Jensen A.J. , Kleveland C.R. , Moghaddam A. , Haaheim H. , Hjelmevoll S.O. , Skogen V.
Published: March 2012

Background  The prevalence of Mycoplasma genitalium and Ureaplasma genitalium in populations outside sexually transmitted infection clinics in Norway is unknown.

Objective  To assess the prevalence of potential sexually transmitted organisms in a non‐clinical setting, among college students in Northern Norway.

Methods  In total 655 students, 449 men and 206 women, were tested for Chlamydia trachomatis, M. genitalium, and U. urealyticum by nucleic acid amplification testing of urine samples. All subjects completed questionnaires.

Results  Among the included men, the prevalences of C. trachomatis, M. genitalium, and U. urealyticum were 4.2%, 1.1% and 8.9%, respectively. Prevalence among included women was 1.9%, 1% and 8.2%, respectively. In men, the number of sexual partners in the preceding 6 months was associated with prevalence of U. urealyticum and C. trachomatis.

Conclusions  U. urealyticum appeared more prevalent than C. trachomatis and increased number of sexual partners was associated with increased risk of a positive test. M. genitalium had a low prevalence.
Spatio‐temporal partitioning among large carnivores in relation to major prey species in Western Ghats
Authors: Ramesh T. , Kalle R. , Sankar K. , Qureshi Q.
Published: March 2012

Spatio‐temporal partitioning is a viable mechanism for minimizing resource competition among sympatric species. The occurrence of sympatric large carnivores – tiger Panthera tigris, leopard Panthera pardus and dhole Cuon alpinus – in forests of the Indian subcontinent is complemented with high dietary overlap. We characterized temporal and spatial patterns of large carnivores with major prey species using photo‐captures from 50 camera trap stations in Mudumalai Tiger Reserve, Western Ghats during 2008–2010. We tested whether major prey species' activity and spatial use acted as drivers for coexistence among large carnivores. Tiger exhibited cathemeral activity in the night and is spatially correlated with sambar and gaur, supporting hypotheses related to large‐sized prey. Leopard was active throughout the day and is spatially correlated with almost all prey species with no active separation from tiger. Dhole exhibited diurnal activity and spatial use in relation to chital and avoided felids to a certain extent. Leopard exhibited spatial correlation with tiger and dhole, while tiger did not correlate with dhole. Leopard exhibited relatively broader temporal and spatial tolerance due to its generalist nature, which permits opportunistic exploitation of resources. This supports the hypothesis that predators actively used areas at the same time as their principal prey species depending upon their body size and morphological adaptation. We conclude that resource partitioning in large carnivores by activity and spatial use of their principal prey governs spatio‐temporal separation in large carnivores.
Temperature‐Dependent Properties of (Bi1/2Na1/2)TiO3–(Bi1/2K1/2)TiO3–SrTiO3 Lead‐Free Piezoceramics
Authors: Wang Ke , Hussain Ali , Jo Wook , Rödel Jürgen
Published: March 2012

Ferroelectric and piezoelectric properties of SrTiO3–modified (0, 3, and 5 mol%) 0.8Bi1/2Na1/2TiO3–0.2Bi1/2K1/2TiO3 lead‐free piezoceramics were investigated as a model system in an attempt to lay a guideline for developing lead‐free piezoelectric materials with large strains. Two guidelines, one for the choice of base composition and the other for the choice of chemical modifiers, were assumed from our current understanding of the mechanism involved. Dielectric permittivity of both poled and unpoled samples was measured and compared, leading to a conclusion that the frequency‐independent anomaly (TF‐R) is the temperature at which induced‐ferroelectric order converts back to relaxor state. The correlation between TF‐R and depolarization temperature (Td) was shown by the comparison with Td determined by thermally stimulated depolarization current measurements, whereas the ferroelectric‐relaxor transition temperature TF‐R was determined using poled samples. A large unipolar strain of 0.36% (Smax/Emax = 600 pm/V) at a driving field of 6 kV/mm was obtained at room temperature for a SrTiO3 content of 5 mol%. Temperature‐dependent measurements of both polarization and strain from room temperature to 200°C revealed that the origin of the large strain is due to a reversible field‐induced ergodic relaxor‐to‐ferroelectric phase transformation.
‘No strings attached?’: How attribution of disinterested support affects employee retention
Authors: Mignonac Karim , Richebé Nathalie
Published: March 2012

Appearance of disinterestedness is a social norm that has long been recognised by social scientists as essential to the development of social exchange relationships. Despite the predominance of social exchange theory within the field of management, management scholars have so far largely overlooked the role of this norm in their models. This study aims to fill this gap by investigating how employees' attribution of disinterested organisational support (i.e. support perceived by employees as not resulting from an underlying calculation) is related to employee retention. The hypotheses were tested in a longitudinal study of 151 management‐level employees. Results showed that perceptions of disinterested support decrease employee voluntary turnover through enhancing perceptions of organisational support and organisational commitment, and lessening turnover intention.
Chemopreventive evaluation of Tephrosia purpurea against N-nitrosodiethylamine-induced hepatocarcinogenesis in Wistar rats
Authors: Hussain Talib , Siddiqui Hefazat H , Fareed Sheeba , Vijayakumar Madhavan , Rao Chandana Venkateswara
Published: March 2012

Objectives

The chemopreventive potential of Tephrosia purpurea extract (TPE) on N-nitrosodiethylamine (NDEA)-induced hepatocellular carcinoma (HCC) in Wistar rats was assessed.

Methods

HCC was induced by a single intraperitoneal injection of NDEA (200 mg/kg) followed by subcutaneous injections of CCl4 (3 ml/kg per week) for six weeks. After administration of the carcinogen, 200 and 400 mg/kg TPE were administered orally once a day throughout the study.

Key findings

The levels of liver cancer markers, including α-fetoprotein and carcinoembryonic antigen, were substantially increased by NDEA treatment. TPE treatment significantly reduced liver injury and restored the entire liver cancer markers. Additionally, TPE markedly normalized the activity of antioxidant enzymes, namely lipid peroxidation, reduced glutathione, catalase, superoxide dismutase, glutathione peroxidase and glutathione-S-transferase in the liver of NDEA-treated rats. Treatment with TPE significantly reduced the nodule incidence and multiplicity in the carcinogen-bearing rats. Histological observations of the liver tissues correlated with the biochemical observations.

Conclusions

These findings powerfully support that T. purpurea prevented lipid peroxidation, suppressed the tumour burden, and promoted enzymatic and nonenzymatic antioxidant defence systems during NDEA-induced hepatocarcinogenesis. This might have been due to modulating the antioxidant defence status, which contributed to its anticarcinogenic potential.
Cognitive load privileges memory‐based over data‐driven processing, not group‐level over person‐level processing
Authors: Skorich Daniel P. , Mavor Kenneth I.
Published: March 2012

In the current paper, we argue that categorization and individuation, as traditionally discussed and as experimentally operationalized, are defined in terms of two confounded underlying dimensions: a person/group dimension and a memory‐based/data‐driven dimension. In a series of three experiments, we unconfound these dimensions and impose a cognitive load. Across the three experiments, two with laboratory‐created targets and one with participants’ friends as the target, we demonstrate that cognitive load privileges memory‐based over data‐driven processing, not group‐ over person‐level processing. We discuss the results in terms of their implications for conceptualizations of the categorization/individuation distinction, for the equivalence of person and group processes, for the ultimate ‘purpose’ and meaningfulness of group‐based perception and, fundamentally, for the process of categorization, broadly defined.
Supplementation of a suboptimal protein dose with leucine or essential amino acids: effects on myofibrillar protein synthesis at rest and following resistance exercise in men
Authors: Churchward‐Venne Tyler A. , Burd Nicholas A. , Mitchell Cameron J. , West Daniel W. D. , Philp Andrew , Marcotte George R. , Baker Steven K. , Baar Keith , Phillips Stuart M.
Published: March 2012

Key points

Essential amino acids (EAAs) stimulate increased rates of myofibrillar protein synthesis (MPS).

Leucine is a key regulator of MPS in rodents; however, its importance relative to the other EAAs is not clear.

About 20 g of protein maximally stimulates MPS after resistance exercise in young men, but we do not know if smaller doses can be made better by adding certain amino acids.

We report that a suboptimal dose of whey protein (6.25 g) supplemented with either leucine or a mixture of EAAs without leucine stimulates MPS similar to 25 g of whey protein under resting conditions; however, only 25 g of whey sustains exercise‐induced rates of MPS.

Adding leucine or a mixture of EAAs without leucine to a suboptimal dose of whey is as effective as 25 g whey at stimulating fed rates of MPS; however, 25 g of whey is better suited to increase resistance exercise‐induced muscle anabolism.
Quantifying the gantry sag on linear accelerators and introducing an MLC‐based compensation strategy
Authors: Du Weiliang , Gao Song , Wang Xiaochun , Kudchadker Rajat J.
Published: March 2012

Purpose:

Gantry sag is one of the well‐known sources of mechanical imperfections that compromise the spatial accuracy of radiation dose delivery. The objectives of this study were to quantify the gantry sag on multiple linear accelerators (linacs), to investigate a multileaf collimator (MLC)‐based strategy to compensate for gantry sag, and to verify the gantry sag and its compensation with film measurements.

Methods:

The authors used the Winston–Lutz method to measure gantry sag on three Varian linacs. A ball bearing phantom was imaged with megavolt radiation fields at 10° gantry angle intervals. The images recorded with an electronic portal imaging device were analyzed to derive the radiation isocenter and the gantry sag, that is, the superior–inferior wobble of the radiation field center, as a function of the gantry angle. The authors then attempted to compensate for the gantry sag by applying a gantry angle‐specific correction to the MLC leaf positions. The gantry sag and its compensation were independently verified using film measurements.

Results:

Gantry sag was reproducible over a six‐month measurement period. The maximum gantry sag was found to vary from 0.7 to 1.0 mm, depending on the linac and the collimator angle. The radiation field center moved inferiorly (i.e., away from the gantry) when the gantry was rotated from 0° to 180°. After the MLC leaf position compensation was applied at 90° collimator angle, the maximum gantry sag was reduced to <0.2 mm. The film measurements at gantry angles of 0° and 180° verified the inferior shift of the radiation fields and the effectiveness of MLC compensation.

Conclusions:

The results indicate that gantry sag on a linac can be quantitatively measured using a simple phantom and an electronic portal imaging device. Reduction of gantry sag is feasible by applying a gantry angle‐specific correction to MLC leaf positions at 90° collimator angle.
A filtered backprojection MAP algorithm with nonuniform sampling and noise modeling
Authors: Zeng Gengsheng L.
Published: March 2012

Purpose:

The goal of this paper is to extend our recently developed FBP (filtered backprojection) algorithm, which has the same characteristics of an iterative Landweber algorithm, to an FBP algorithm with the same characteristics of an iterative MAP (maximuma posteriori) algorithm. The newly developed FBP algorithm also works when the angular sampling interval is not uniform. The projection noise variance can be modeled using a view‐based weighting scheme.

Methods:

The new objective function contains projection noise model dependent weighting factors and image dependent prior (i.e., a Bayesian term). The noise weighting is view‐by‐view based. For the first time, the FBP algorithm is able to model the projection noise. Based on the formulation of the iterative Landweber MAP algorithm, a frequency‐domain window function is derived for each iteration of the Landweber MAP algorithm. As a result, the ramp filter and the windowing function are both modified by the Bayesian component. This new FBP algorithm can be applied to a projection data set that is not uniformly sampled.

Results:

Computer simulations show that the new FBP‐MAP algorithm with window function indexk and the iterative Landweber MAP algorithm with iteration number k give similar reconstructions in terms of resolution and noise texture. An example of transmission x‐ray CT shows that the noise modeling method is able to significantly reduce the streaking artifacts associated with low‐dose CT.

Conclusions:

View‐based noise weighting scheme can be introduced to the FBP algorithm as a weighting factor in the window function. The new FBP algorithm is able to provide similar results to the iterative MAP algorithm if the ramp filter is modified with a additive term. Nonuniform sampling and sensitivity can be accommodated by proper backprojection weighting.
Anti-Invasive Adjuvant Therapy with Imipramine Blue Enhances Chemotherapeutic Efficacy Against Glioma
Authors: Munson Jennifer M. , Fried Levi , Rowson Sydney A. , Bonner Michael Y. , Karumbaiah Lohitash , Diaz Begoña , Courtneidge Sara A. , Knaus Ulla G. , Brat Daniel J. , Arbiser Jack L. , Bellamkonda Ravi V.
Published: March 2012

A novel compound, Imipramine Blue, enhances efficacy of chemotherapy in a single treatment against a rodent astrocytoma model in vivo by inhibiting cell invasion.
Targeting of AML1-ETO in t(8;21) Leukemia by Oridonin Generates a Tumor Suppressor–Like Protein
Authors: Zhen Tao , Wu Chuan-Feng , Liu Ping , Wu Hai-Yan , Zhou Guang-Biao , Lu Ying , Liu Jian-Xiang , Liang Yang , Li Keqin Kathy , Wang Yue-Ying , Xie Yin-Yin , He Miao-Miao , Cao Huang-Ming , Zhang Wei-Na , Chen Li-Min , Petrie Kevin , Chen Sai-Juan , Chen Zhu
Published: March 2012

Oridonin treats AML by generating a truncated version of the AML1-ETO oncoprotein that functions as a tumor suppressor.
Colocalization of Inflammatory Response with B7-H1 Expression in Human Melanocytic Lesions Supports an Adaptive Resistance Mechanism of Immune Escape
Authors: Taube Janis M. , Anders Robert A. , Young Geoffrey D. , Xu Haiying , Sharma Rajni , McMiller Tracee L. , Chen Shuming , Klein Alison P. , Pardoll Drew M. , Topalian Suzanne L. , Chen Lieping
Published: March 2012

Activated tumor-infiltrating lymphocytes may induce B7-H1 on melanocytes, which suggests adaptive resistance to antitumor immunity.
Intratumor Heterogeneity: Seeing the Wood for the Trees
Authors: Yap Timothy A. , Gerlinger Marco , Futreal P. Andrew , Pusztai Lajos , Swanton Charles
Published: March 2012

Intratumor genetic heterogeneity impedes development of new therapeutics and biomarkers that predict drug response.
Control of Entamoeba histolytica Adherence Involves Metallosurface Protease 1, an M8 Family Surface Metalloprotease with Homology to Leishmanolysin
Authors: Teixeira Jose E. , Sateriale Adam , Bessoff Kovi E. , Huston Christopher D.
Published: March 2012

Invasive amebiasis due toEntamoeba histolyticainfection is an important cause of morbidity in developing countries. TheE. histolyticagenome contains two homologues to the metalloprotease leishmanolysin gene,Entamoeba histolytica MSP-1(EhMSP-1) andEhMSP-2, while the commensal amebaEntamoeba disparhas lostEhMSP-1. In this study, we sought to characterizeE. histolyticametallosurface protease 1 (EhMSP-1). Using immunoprecipitation and a model substrate, we found that EhMSP-1 was a functional metalloprotease. Confocal microscopy and flow cytometry revealed that EhMSP-1 localized to the cell surface and revealed the existence of distinct, nonclonal trophozoite populations with high and low EhMSP-1 surface abundance that became synchronized following serum starvation. Phenotypic assays were performed after silencingEhMSP-1. Adherence of EhMSP-1-deficient trophozoites to tissue culture cell monolayers was more than five times greater than that of control amebas, but surface staining of several antigens, including the galactose adherence lectin, was unchanged.EhMSP-1silencing similarly increased adherence to both viable and apoptotic Jurkat lymphocytes. Tissue culture cell monolayer destruction was reduced byEhMSP-1silencing, although it was blocked almost completely by inhibiting cysteine proteases. Consistent with a primary defect in regulation of amebic adherence,EhMSP-1silencing also resulted in reduced mobility on tissue culture cell monolayers and in increased phagocytosis. In conclusion, EhMSP-1 was shown to be a surface metalloprotease involved in regulation of amebic adherence, with additional effects on cell motility, cell monolayer destruction, and phagocytosis.
Complete Genome Sequence of Lactococcus lactis IO-1, a Lactic Acid Bacterium That Utilizes Xylose and Produces High Levels of
l
-Lactic Acid
Authors: Kato Hiroaki , Shiwa Yuh , Oshima Kenshiro , Machii Miki , Araya-Kojima Tomoko , Zendo Takeshi , Shimizu-Kadota Mariko , Hattori Masahira , Sonomoto Kenji , Yoshikawa Hirofumi
Published: March 2012

We report the complete genome sequence of
Lactococcus lactis
IO-1 (= JCM7638). It is a nondairy lactic acid bacterium, produces nisin Z, ferments xylose, and produces predominantly
l
-lactic acid at high xylose concentrations. From ortholog analysis with other five
L. lactis
strains, IO-1 was identified as
L. lactis
subsp.
lactis
.
Genome Sequence of Paenibacillus sp. Strain Aloe-11, an Endophytic Bacterium with Broad Antimicrobial Activity and Intestinal Colonization Ability
Authors: Li Neng-Zhang , Xia Tian , Xu Ya-Li , Qiu Rong-Rong , Xiang Heng , He Dan , Peng Yuan-Yi
Published: March 2012

Paenibacillus
sp. strain Aloe-11, a Gram-positive, spore-forming, facultatively anaerobic bacterium isolated from the root of
Aloe chinensis
in the southwest region of China, has excellent antibiotic activity and intestine colonization ability. Here, we present the 5.8-Mb draft genome sequence of
Paenibacillus
sp. strain Aloe-11.
Genome Sequence of Extracellular-Protease-Producing Alishewanella jeotgali Isolated from Traditional Korean Fermented Seafood
Authors: Jung Jaejoon , Chun Jongsik , Park Woojun
Published: March 2012

Alishewanella jeotgali
MS1
T
(= KCTC 22429
T
= JCM 15561
T
) was isolated from a traditional Korean fermented seafood, gajami sikhae (jeotgal), and has been reported as a novel species.
A. jeotgali
was proven to have extracellular proteolytic activity, which may play an important role in the fermentation environment of food containing fish flesh. Here, we present the genome sequence of
Alishewanella jeotgali
MS1
T
as the first sequenced strain in the genus
Alishewanella
and its taxonomic relatives.
Capacity management, not stock status or economics, drives fleet dynamics in the Bay of Biscay ecosystem on a decadal time scale
Authors: Rochet Marie-Joëlle , Daurès Fabienne , Trenkel Verena M.
Published: March 2012

This paper introduces a semiqualitative approach to analyse the joint dynamics of fleets and stocks in a multispecies, multifleet fishery. We ask whether changes in fleets affect resource dynamics and whether trends in resource influence fleet dynamics more than external drivers do. External drivers include vessel buyback, fuel price, and fish prices, as well as environmental fluctuations. Resource status is measured by abundance and length metrics; fleet capacity is measured by total horse power, and economic metrics such as profitability and earnings are examined as well. A maximum likelihood approach is used to identify the combined metric trends with the largest support in the data. The approach is applied to the French Bay of Biscay fisheries in 2000–2007. Combined-metric time trends suggest that decreases in fleet capacity did not result in decreasing fishing impacts; trends in stocks and fish prices were not the major drivers of changes in fleets either. Rather, the vessel buyback program might have been the main factor determining fleet dynamics over that period.
Origins of invasive piscivores determined from the strontium isotope ratio (87Sr/86Sr) of otoliths
Authors: Wolff Brian A. , Johnson Brett M. , Breton André R. , Martinez Patrick J. , Winkelman Dana L.
Published: March 2012

We examined strontium isotope ratios (87Sr/86Sr) in fish otoliths to determine the origins of invasive piscivores in the Upper Colorado River Basin (UCRB, western USA). We examined87Sr/86Sr from fishes in different reservoirs, as well as the temporal stability and interspecies variability of87Sr/86Sr of fishes within reservoirs, determined if87Sr/86Sr would be useful for “fingerprinting” reservoirs where invasive piscivores may have been escaping into riverine habitat of endangered fishes in the UCRB, and looked for evidence that such movement was occurring. Our results showed that in most cases87Sr/86Sr was unique among reservoirs, overlapped among species in a given reservoir, and was temporally stable across years. We identified the likely reservoir of origin of river-caught fish in some cases, and we were also able to determine the year of possible escapement. The approach allowed us to precisely describe the87Sr/86Sr fingerprint of reservoir fishes, trace likely origins of immigrant river fish, and exclude potential sources, enabling managers to focus control efforts more efficiently. Our results demonstrate the potential utility of87Sr/86Sr as a site-specific and temporally stable marker for reservoir fish and its promise for tracking fish movements of invasive fishes in river–reservoir systems.
SPAM (Sex-Structured Pandalus Assessment Model): a stock assessment model for Pandalus stocks
Authors: Drouineau Hilaire , Savard Louise , Desgagnés Mathieu , Duplisea Daniel
Published: March 2012

Despite the economic importance of Pandalus shrimp fisheries, few analytical tools have been developed to assess their stocks, and traditional stock assessment models are not appropriate because of biological specificities of Pandalus species. In this context, we propose SPAM (Sex-Structured Pandalus Assessment Model), a model dedicated to protandric hermaphrodite pandalids stock assessment. Pandalids are difficult to assess because the cues affecting sex change, size at recruitment, and mortality variability are not well understood or characterized. The novel structure of the model makes it possible to adequately describe variability in natural mortality by stage and in time, as well as variability in size at sex change and recruitment. The model provides traditional stock assessment outputs, such as fishing mortality estimates and numbers of individuals, and provides in addition yearly natural mortality estimates. The model is applied to the exploited shrimp stock of Pandalus borealis in Sept-Îles (Québec, Canada) as an illustrative example of the utility of the approach.
Using model-based inference to evaluate global fisheries status from landings, location, and life history data
Authors: Thorson James T. , Branch Trevor A. , Jensen Olaf P.
Published: March 2012

Assessing fishery collapses worldwide is hindered by the lack of biomass data for most stocks, leading to the use of landings-based proxies or the assumption that existing stock assessments are globally representative. We argue that the use of sparse assessments to evaluate fishery status requires model-based inference because assessment availability varies spatially and temporally, and we derive a model that extrapolates from assessment results to available landings, life history, and location data. This model uses logistic regression to classify stocks into different prediction bins and estimates the probability of collapse in each using cross-validation. Results show that landings, life history, and location are informative to discriminate among different probabilities of collapse. We find little evidence that regions with fewer assessments have a greater proportion of collapsed stocks, while acknowledging weak inferential support regarding regions with one or fewer assessments. Our extrapolation suggests that 4.5%–6.5% of stocks defined by landings data are collapsed, but that this proportion is increasing. Finally, we propose a research agenda that combines stock assessment and landings databases while overcoming limitations in each.
EVENT SHAPES FOR HADRONIC FINAL STATE: EXPERIMENTAL REVIEW
Authors: OKOROKOV V. A.
Published: March 2012

The analysis is presented for the first moments of collective observable distributions in two-jet events for various interaction types and for wide initial energy range. These observables include sphericity, thrust, components of transverse particle momentum, alignment and planarity. Database of experimental results created in the framework of the paper includes data for all interactions. Energy dependencies of average values for collective observables except components of transverse momentum show universal behavior for various interactions. Particle transverse momentum as well as its components increase faster for e+e- interaction with growth of [Formula: see text], than that for other interactions. Empirical analytical functions are suggested for description of energy dependence for all collective observables under study with exception of infrared-stable thrust variable. Energy dependence for average thrust is compared with QCD predictions including perturbative part and analytical phenomenological corrections which account for nonperturbative effects. Dispersive model and single dressed gluon approximation are considered for description of energy dependence of first moment of thrust distribution and estimation of strong coupling constant for various interactions as well as for joint sample. The dispersive model allow to describe average thrust versus initial energy in wide range of [Formula: see text] down to strongly nonperturbative domain [Formula: see text] at qualitative level at least. Study of event shape observables allows to obtain estimations of αS(MZ) which are in reasonable agreement both with world average value and with results extracted in the framework of other methods. Using suggested analytical fitted functions some estimations of values of collective parameters under study have been obtained for present and future facilities. In TeV energy domain average values of collective observables either depend on [Formula: see text] weakly or do not depend on initial energy at all within errors. Thus, the TeV scale can be considered as an estimation of the low boundary of asymptotic region for traditional collective parameters. Usually, multiplicity dependence of collective observables under consideration agree with power function in energy domain [Formula: see text] at qualitative level at least. Behavior of sphericity versus multiplicity and comparison of experimental results with model calculations allow to suggest that the universal estimation of the low energy boundary for experimental appearance of event jet structure in multiparticle production processes is [Formula: see text].
MAGNETIC FIELD GENERATION IN HIGGS INFLATION MODEL
Authors: DAS MOUMITA , MOHANTY SUBHENDRA
Published: March 2012

We study the generation of magnetic field in Higgs inflation models where the Standard Model Higgs boson has a large coupling to the Ricci scalar. We couple the Higgs field to the electromagnetic fields via a nonrenormalizable dimension six operator suppressed by the Planck scale in the Jordan frame. We show that by choosing the Higgs coupling λ(MZ) = 0.132 (which corresponds to mh = 126 GeV in keeping with the recent measurements by ATLAS and CMS) and curvature coupling ξ(MZ) = 103 we can generate comoving magnetic fields of 10-7 Gauss at present and comoving coherence length of 100 kpc. The problem of large back-reaction which is generic in the usual inflation models of magneto-genesis is avoided as the back-reaction is suppressed by the large Higgs-curvature coupling.
EXACT TRAVELING WAVE SOLUTIONS AND THEIR BIFURCATIONS FOR THE KUDRYASHOV–SINELSHCHIKOV EQUATION
Authors: LI JIBIN , CHEN GUANRONG
Published: March 2012

By using the approach of dynamical systems, the bifurcations of phase portraits for the traveling system of the Kudryashov–Sinelshchikov equation with ν = δ = 0 are studied, in different parametric regions of (α, c)-parametric plane. Corresponding to different phase orbits of the traveling system, more than 26 exact explicit traveling wave solutions are derived. The dynamics of singular nonlinear traveling system is completely determined.
EFFECTIVE GPU ACCELERATION OF LARGE SCALE, ASYNCHRONOUS SIMULATIONS ON GRAPHS
Authors: ARENDT DUSTIN , CAO YANG
Published: March 2012

The recent emergence of GPGPU programming has resulted in a number of very efficient, but ultimately ad-hoc implementations of GPU accelerated simulations of complex systems. Because developing applications for the GPU is still a difficult and time consuming task, efficient GPU parallelizations of general purpose modeling frameworks are very useful. The dimer automaton is a stochastic modeling and simulation framework with a good balance of robustness, generality, and simplicity with capacity to model a wide range of phenomena. A major advantage of dimer automata is the ease in which they can be applied to any space that can be represented as a graph. Therefore, we have developed an efficient GPU implementation of dimer automata that runs up to 80 times faster than the serial implementation.
A Modular Machine Learning System for Flow-Level Traffic Classification in Large Networks
Authors: Jin Yu , Duffield Nick , Erman Jeffrey , Haffner Patrick , Sen Subhabrata , Zhang Zhi-Li
Published: March 2012

The ability to accurately and scalably classify network traffic is of critical importance to a wide range of management tasks of large networks, such as tier-1 ISP networks and global enterprise networks. Guided by the practical constraints and requirements of traffic classification in large networks, in this article, we explore the design of an accurate and scalable machine learning based flow-level traffic classification system, which is trained on a dataset of flow-level data that has been annotated with application protocol labels by a packet-level classifier. Our system employs a lightweight
modular architecture
, which combines a series of simple linear binary classifiers, each of which can be efficiently implemented and trained on vast amounts of flow data in parallel, and embraces three key innovative mechanisms,
weighted threshold sampling, logistic calibration
, and
intelligent data partitioning
, to achieve scalability while attaining high accuracy. Evaluations using real traffic data from multiple locations in a large ISP show that our system accurately reproduces the labels of the packet level classifier when runs on (unlabeled) flow records, while meeting the scalability and stability requirements of large ISP networks. Using training and test datasets that are two months apart and collected from two different locations, the flow error rates are only 3% for TCP flows and 0.4% for UDP flows. We further show that such error rates can be reduced by combining the information of spatial distributions of flows, or
collective traffic statistics
, during classification. We propose a novel two-step model, which seamlessly integrates these collective traffic statistics into the existing traffic classification system. Experimental results display performance improvement on all traffic classes and an overall error rate reduction by 15%. In addition to a high accuracy, at runtime, our implementation easily scales to classify traffic on 10Gbps links.
Describing the What and Why of Students’ Difficulties in Boolean Logic
Authors: Herman Geoffrey L. , Loui Michael C. , Kaczmarczyk Lisa , Zilles Craig
Published: March 2012

The ability to reason with formal logic is a foundational skill for computer scientists and computer engineers that scaffolds the abilities to design, debug, and optimize. By interviewing students about their understanding of propositional logic and their ability to translate from English specifications to Boolean expressions, we characterized common misconceptions and novice problem-solving processes of students who had recently completed a digital logic design class. We present these results and discuss their implications for instruction and the development of pedagogical assessment tools known as concept inventories.
Representing users in accessibility research
Authors: Sears Andrew , Hanson Vicki L.
Published: March 2012

The need to study representative users is widely accepted within the human-computer interaction (HCI) community. While exceptions exist, and alternative populations are sometimes studied, virtually any introduction to the process of designing user interfaces will discuss the importance of understanding the intended users as well as the significant impact individual differences can have on how effectively individuals can use various technologies. HCI researchers are expected to provide relevant demographics regarding study participants as well as information about experience using similar technologies. Yet in the field of accessibility, we continue to see studies that do not appropriately include representative users. Highlighting ways to remedy this multifaceted problem, we argue that expectations regarding how accessibility research is conducted and reported must be raised if this field is to have the desired impact with regard to inclusive design, the information technologies studied, and the lives of the individuals studied.
Some Algorithms for Finding Fixed Points and Solutions of Variational Inequalities
Authors: Jung Jong Soo
Published: March 2012

We introduce new implicit and explicit algorithms for finding the fixed point of a k‐strictly pseudocontractive mapping and for solving variational inequalities related to the Lipschitzian and strongly monotone operator in Hilbert spaces. We establish results on the strong convergence of the sequences generated by the proposed algorithms to a fixed point of a k‐strictly pseudocontractive mapping. Such a point is also a solution of a variational inequality defined on the set of fixed points. As direct consequences, we obtain the unique minimum‐norm fixed point of a k‐strictly pseudocontractive mapping.
An Efficient One‐Pot Synthesis of 1,8‐Dioxodecahydroacridines Using Silica‐Supported Polyphosphoric Acid (PPA‐SiO2) under Solvent‐Free Conditions
Authors: Moeinpour Farid , Khojastehnezhad Amir
Published: March 2012

Silica gel–supported polyphosphoric acid (PPA‐SiO2) was found to be an efficient catalyst for the synthesis of 1,8‐dioxodecahydroacridines via one‐pot three‐component condensation of aryl aldehydes, dimedone, and ammonium acetate or 4‐methyl aniline in high yields, easy workup procedure and short period of times. The catalyst was separated by simple filtration and used in the reaction three times without any significant loss of its activity.
ICP‐OES Determination of Trace Metal Ions after Preconcentration Using Silica Gel Modified with 1,2‐Dihydroxyanthraquinone
Authors: Alghanmi Reem M.
Published: March 2012

A new chelating matrix was prepared by immobilizing 1,2‐dihydr‐oxyanthraquinone, or alizarin (AZ), on silica gel modified with (3‐aminopropyl)trimethoxysilane. The matrix was characterized by FTIR spectroscopy and elemental analysis. The new matrix was used to preconcentrate Cd(II), Cu(II), Ni(II), Pb(II) and Zn(II) prior to their determination by inductively coupled plasma optical emission spectrometry (ICP‐OES). The optimum pH was 5 and the optimum extraction time was approximately 15 minutes using the batch method. Common electrolytes and metal ions did not interfere with the separation and determination of the analytes. The adsorption capacity of the new sorbent was 67.4, 163.5, 212.8, 76.4 and 180.3 μmol/g for Cd(II), Cu(II), Ni(II), Pb(II) and Zn(II), respectively. The relative standard deviations (RSD) were less than 3.0%. This method allowed for successful separation and preconcentration of trace metal ions in different water samples with satisfactory results.
Spectrophotometric Determination of Malathion in Environmental Samples
Authors: Venugopal N. V. S. , Sumalatha B. , Syedabano
Published: March 2012

A simple, rapid, sensitive, and precise spectrophotometric method for the determination of Malathion is described. The method is based on the decomposition of Malathion in the presence of alcoholic KOH. Dimethyldithiophosphate produced is made to react with Ammonium meta vanadate in Nitric acid with the formation of blue color. Acid degradation of too slow to be important under environmental reaction conditions. However, alkaline degradation is too fast to be a pathway in environmental condition. The products of alkaline degradation are temperature dependant. The absorbance maximum was observed at 760 nm. The Beers law is obeyed up to 11 ppm. Interference study was carried for other pesticides.
Application of Circuit Model for Photovoltaic Energy Conversion System
Authors: Pandiarajan Natarajan , Ramaprabha Ramabadran , Muthu Ranganath
Published: March 2012

Circuit model of photovoltaic (PV) module is presented in this paper that can be used as a common platform by material scientists and power electronic circuit designers to develop better PV power plant. Detailed modeling procedure for the circuit model with numerical dimensions is presented using power system blockset of MATLAB/Simulink. The developed model is integrated with DC-DC boost converter with closed-loop control of maximum power point tracking (MPPT) algorithm. Simulation results are validated with the experimental setup.
Minilaparoscopic Colorectal Resections: Technical Note
Authors: Bona S. , Molteni M. , Montorsi M.
Published: March 2012

Laparoscopic colorectal resections have been shown to provide short-term advantages in terms of postoperative pain, general morbidity, recovery, and quality of life. To date, long-term results have been proved to be comparable to open surgery irrefutably only for colon cancer. Recently, new trends keep arising in the direction of minimal invasiveness to reduce surgical trauma after colorectal surgery in order to improve morbidity and cosmetic results. The few reports available in the literature on single-port technique show promising results. Natural orifices endoscopic techniques still have very limited application. We focused our efforts in standardising a minilaparoscopic technique (using 3 to 5 mm instruments) for colorectal resections since it can provide excellent cosmetic results without changing the laparoscopic approach significantly. Thus, there is no need for a new learning curve as minilaparoscopy maintains the principle of instrument triangulation. This determines an undoubted advantage in terms of feasibility and reproducibility of the procedure without increasing operative time. Some preliminary experiences confirm that minilaparoscopic colorectal surgery provides acceptable results, comparable to those reported for laparoscopic surgery with regard to operative time, morbidity, and hospital stay. Randomized controlled studies should be conducted to confirm these early encouraging results.
On the Relationship between Field Amplitude Distribution, Its Maxima Distribution, and Field Uniformity inside a Mode-Stirred Reverberation Chamber
Authors: García-Fernández M. A. , Decroze C. , Carsenat D. , Arsalane N. , Andrieu G.
Published: March 2012

A mode-stirred reverberation chamber (RC) is nowadays a commonly accepted performing tool for over-the-air (OTA) communication system evaluation, and their standardization is underway. Before performing active measurements of wireless communication systems using an RC, field uniformity inside the RC working volume has to be measured following the calibration method described in IEC standards 61000-4-21 and 61000-4-3, which requires 24 calibration measurements of field amplitude. In this contribution, we present the statistical laws that describe electromagnetic field maxima distribution, and based on them, a novel expression that could be useful to obtain a lower limit for the number of stirrer positions required at least to obtain a specific value for the normalized dispersion used to evaluate field uniformity with the IEC calibration method, being therefore of particular interest for OTA measurements.
Pexophagy: The Selective Degradation of Peroxisomes
Authors: Till Andreas , Lakhani Ronak , Burnett Sarah F. , Subramani Suresh
Published: March 2012

Peroxisomes are single-membrane-bounded organelles present in the majority of eukaryotic cells. Despite the existence of great diversity among different species, cell types, and under different environmental conditions, peroxisomes contain enzymes involved inβ-oxidation of fatty acids and the generation, as well as detoxification, of hydrogen peroxide. The exigency of all eukaryotic cells to quickly adapt to different environmental factors requires the ability to precisely and efficiently control peroxisome number and functionality. Peroxisome homeostasis is achieved by the counterbalance between organelle biogenesis and degradation. The selective degradation of superfluous or damaged peroxisomes is facilitated by several tightly regulated pathways. The most prominent peroxisome degradation system uses components of the general autophagy core machinery and is therefore referred to as “pexophagy.” In this paper we focus on recent developments in pexophagy and provide an overview of current knowledge and future challenges in the field. We compare different modes of pexophagy and mention shared and distinct features of pexophagy in yeast model systems, mammalian cells, and other organisms.
Envelope and Wavelet Transform for Sound Localisation at Low Sampling Rates in Wireless Sensor Networks
Authors: Bouzid O. M. , Tian G. Y. , Neasham J. , Sharif B.
Published: March 2012

High sampling frequencies in acoustic wireless sensor network (AWSN) are required to achieve precise sound localisation. But they are also mean analysis time and memory intensive (i.e., huge data to be processed and more memory space to be occupied which form a burden on the nodes limited resources). Decreasing sampling rates below Nyquist criterion in acoustic source localisation (ASL) applications requires development of the existing time delay estimation techniques in order to overcome the challenge of low time resolution. This work proposes using envelope and wavelet transform to enhance the resolution of the received signals through the combination of different time-frequency contents. Enhanced signals are processed using cross-correlation in conjunction with a parabolic fit interpolation to calculate the time delay accurately. Experimental results show that using this technique, estimation accuracy was improved by almost a factor of 5 in the case of using 4.8 kHz sampling rate. Such a conclusion is useful for developing precise ASL without the need of any excessive sensor resources, particularly for structural health monitoring applications.
Modelling Reef Fish Population Responses to Fisheries Restrictions in Marine Protected Areas in the Coral Triangle
Authors: Varkey Divya , Ainsworth Cameron H. , Pitcher Tony J.
Published: March 2012

Marine ecosystem models are used to investigate marine protected area (MPA) benefits for coral reef ecosystems located in Raja Ampat, in the heart of the Coral Triangle. Field data from an integrated and diverse research project is used to develop a spatial ecosystem model using Ecopath, Ecosim, and Ecospace modelling software. The ecological and fisheries responses of a reef ecosystem to different levels of fishing effort restrictions inside MPAs are explored. The trade-offs of allowing some fisheries to operate inside the MPAs versus designating the MPAs as no-take zones are highlighted. The results show that rapid rebuilding of reef fish populations, especially the large charismatic species, requires no-take areas. Distinct trade-offs in spillover benefits are observed between partially fished and no-take MPAs.
Malignant Glaucoma: A Review of the Modern Literature
Authors: Shahid H. , Salmon J. F.
Published: March 2012

Malignant glaucoma is a rare form of glaucoma that typically follows surgery in patients with primary angle closure and primary angle-closure glaucoma. In this paper, the clinical features, classification, pathogenesis, and principles of management are discussed. Despite a high prevalence of primary angle closure glaucoma in South-East Asia, the vast majority of cases of malignant glaucoma are reported in White populations. This may reflect differing mechanisms of angle closure in White and Asian patients, which somehow reduces the likelihood of an aberrant relationship developing between the lens, ciliary body, anterior hyaloid, and vitreous structures within the eye. Although the exact underlying pathogenic mechanism remains unclear, the prognosis is good with modern medical, laser, and surgical treatment modalities.
Isolation, Characterization and Activity of the Flowers of Rhododendron arboreum (Ericaceae)
Authors: Sonar Pankaj Kumar , Singh Ranjit , Khan Shagufta , Saraf Shailendra K.
Published: March 2012

The flowers of Rhododendron arboreum have been reported to possess certain polyphenolic compounds. Thus, this study was aimed at the anti‐microbial and phytochemical screening of the flowers. Important bioactive agents like steroids, saponins and flavonoids were detected in the flowers. Quercetin (a flavonoid) was isolated from the diethyl ether fraction of alcoholic extract by solvent‐solvent extraction method. Isolated quercetin was identified and characterized by chemical tests, M.P., TLC, paper chromatography (with authentic marker) and spectroscopic methods like UV‐Visible, FT‐IR, 1HNMR, 13CNMR and Mass spectroscopy. The anti‐microbial activity of the alcoholic and aqueous extract and isolated quercetin were investigated against five bacterial and two fungal strains by agar well‐diffusion method. The activity was found to be concentration dependent. Ethanolic extract was found to be more active in comparison to the aqueous extract. Hence, isolation was done with ethanolic extract. The lowest effective concentration of quercetin was found to be 12.5 mg/ml against S. aureus and P. aeruginosa. Both extracts and isolated quercetin were found ineffective against fungal strains. Quercetin may be one of the components responsible for the observed anti‐microbial activity of the plant.