bluuebunny/crossref_metadata_2025 huggingface dataset:
Virulence or Niche Factors: What's in a Name?
Authors: Hill Colin
Published: July 2012

The increasing interest in the human microbiota raises some interesting questions about the terminology we use to describe some of the structures and strategies employed by commensal and pathogenic microbes to compete in these complex biological ecosystems. For example, all microbes arriving in the alimentary tract face the task of surviving passage through the stomach, coping with bile, interacting with the immune system, competing with the established microbiota, and obtaining sufficient nutrients to gain a foothold in this hostile environment. It is not surprising then that many gastrointestinal microbes (both pathogens and commensals) use similar strategies to overcome the challenges associated with this particular biological niche. Given that many of these structures and strategies were discovered and characterized in pathogens and because they often play important roles in establishing and maintaining an infection, they have often been characterized as virulence factors. It would be misleading to describe the same strategies and structures found in harmless commensals as “virulence factors,” since they represent a
sine qua non
for life in the gastrointestinal tract. It may be time to reconsider and refer to them as “niche factors,” both in terms of providing scientific accuracy but also in light of the growing interest in using gut microbes as probiotics, where the distinction between virulence factors and niche factors is likely to be very important from a regulatory perspective.
Evidence for Cyclic Di-GMP-Mediated Signaling in Bacillus subtilis
Authors: Chen Yun , Chai Yunrong , Guo Jian-hua , Losick Richard
Published: July 2012

Cyclic di-GMP (c-di-GMP) is a second messenger that regulates diverse cellular processes in bacteria, including motility, biofilm formation, cell-cell signaling, and host colonization. Studies of c-di-GMP signaling have chiefly focused on Gram-negative bacteria. Here, we investigated c-di-GMP signaling in the Gram-positive bacteriumBacillus subtilisby constructing deletion mutations in genes predicted to be involved in the synthesis, breakdown, or response to the second messenger. We found that a putative c-di-GMP-degrading phosphodiesterase, YuxH, and a putative c-di-GMP receptor, YpfA, had strong influences on motility and that these effects depended on sequences similar to canonical EAL and RxxxR—D/NxSxxG motifs, respectively. Evidence indicates that YpfA inhibits motility by interacting with the flagellar motor protein MotA and thatyuxHis under the negative control of the master regulator Spo0A∼P. Based on these findings, we propose that YpfA inhibits motility in response to rising levels of c-di-GMP during entry into stationary phase due to the downregulation ofyuxHby Spo0A∼P. We also present evidence that YpfA has a mild influence on biofilm formation.In toto, our results demonstrate the existence of a functional c-di-GMP signaling system inB. subtilisthat directly inhibits motility and directly or indirectly influences biofilm formation.
Management of acute anterior shoulder dislocation
Authors: Dala-Ali Benan , Penna Marta , McConnell Jamie , Vanhegan Ivor , Cobiella Carlos
Published: July 2012

Shoulder dislocation is the most common large joint dislocation in the body. Recent advances in radiological imaging and shoulder surgery have shown the potential dangers of traditional reduction techniques such as the Kocher's and the Hippocratic methods, which are still advocated by many textbooks. Many non-specialists continue to use these techniques, unaware of their potential risks. This article reviews the clinical and radiographic presentation of dislocation; some common reduction techniques; their risks and success rate; analgesia methods to facilitate the reduction; and postreduction management. Many textbooks advocate methods that have been superceded by safer alternatives. Trainees should learn better and safer relocation methods backed up by the current evidence available.
Self-reported uptake of recommendations after dissemination of medication incident alerts
Authors: Cheung Ka-Chun , Wensing Michel , Bouvy Marcel L , De Smet Peter A G M , van den Bemt Patricia M L A
Published: July 2012

Introduction

In the Netherlands, a Central Medication Incidents Registration (CMR) system is operational. To prevent recurrence of reported medication incidents the CMR sends medication incident alerts with recommendations. It is up to the healthcare workers whether or not to implement the recommendations in clinical practice, which may lead to variations in degrees of uptake of the recommendations.

Objective

The aim of this study was to explore the degree of self-reported uptake of the recommendations and to identify potential determinants associated with successful uptake.

Design

This is a cross-sectional study conducted within a convenience sample of 33 Dutch hospital pharmacies. The study was carried out from April 2009 to September 2010.

Measurements

Three alerts were selected for the study: administration of methotrexate in a dosage of once a day instead of once a week, administration of undiluted potassium-sodium-phosphate concentrate, and administration of glucose 50% instead of 5%. The primary outcome was the degree of self-reported uptake of the specific recommendations and the associations of the degree of uptake with several potential determinants.

Results

Twenty-one hospitals (63.6%) had adopted all recommendations about methotrexate. A quarter of the hospitals (24.2%) had adopted all recommendations related to potassium-sodium-phosphate concentrate. For the alert about glucose 50%, none of the hospitals had implemented all the recommendations. No statistically significant associations between potential determinants and the degree of uptake were found.

Conclusions

This study is the first to investigate the degree of uptake of the recommendations of three different CMR alerts. The alerts varied in the degrees of self-reported uptake of the recommendations, with the methotrexate alert having the highest degree of uptake. No significant associations with potential determinants were found.
Neighbourhoods matter too: the association between neighbourhood socioeconomic position, population density and breast, prostate and lung cancer incidence in Denmark between 2004 and 2008
Authors: Meijer Mathias , Bloomfield Kim , Engholm Gerda
Published: July 2012

Background

Previous studies have shown that cancer incidence is related to a number of individual factors, including socioeconomic status. The aim of this study was to refine the current knowledge about indicators associated with cancer incidence by evaluating the influence of neighbourhood characteristics on breast, prostate and lung cancer incidence in Denmark.

Methods

All women aged 30–83 years were followed for breast cancer between 2004 and 2008, men between 50 and 83 years were followed for prostate cancer and both sexes between ages 50 and 83 were followed for lung cancer. Registry data obtained from Statistics Denmark included age, sex, availability of breast cancer screening, marital status, education, disposable income and occupational socioeconomic status on the individual level and population density and neighbourhood socioeconomic status (the proportion of unemployed) on the parish level. Frailty modelling with individuals on the first level and parishes on the second level was conducted.

Results

A significantly lower HR of breast cancer was found in areas with low population density (HR=0.93; CI 0.88 to 0.99), while neighbourhood unemployment had no effect. Inhabitants of lower unemployment areas had a higher risk of prostate cancer (HR=1.14; CI 1.08 to 1.21) compared with those in higher unemployment areas, whereas population density had no effect. Risk of lung cancer was lower in areas with lowest population density (HR=0.80; CI 0.74 to 0.85) and lowest in areas with lowest unemployment (HR=0.88; CI 0.84 to 0.92).

Conclusions

In addition to individual-level factors, characteristics on the neighbourhood level also have an influence on breast, prostate and lung cancer incidence.
The psychosocial pathway to mental well-being at the local level: investigating the effects of perceived relative position in a deprived area context
Authors: Kearns Ade , Whitley Elise , Bond Lyndal , Egan Matt , Tannahill Carol
Published: July 2012

Background

The study investigated whether perceived relative position was associated with mental well-being for people living in deprived areas, as a contribution to debates about income inequality, relative deprivation and health.

Methods

A survey of 4615 residents of deprived areas of Glasgow measured mental well-being using the WEMWBS scale. Perceived relative position was assessed locally and across wider society in relation to housing, neighbourhood and standard of living. Personal and dwelling characteristics were controlled for.

Results

Mental well-being was found to be positively associated with: perceived relative quality (RR 4.1, 95% CI 2.4 to 6.8) and status (RR 7.1, 95% CI 4.5 to 11.1) of the home; perceived internal reputation of the neighbourhood (RR 4.9, 95% CI 2.9 to 8.2), though not external reputation; and perceived relative standard of living (RR 5.2, 95% CI 3.2 to 8.4). Furthermore, respondents who thought they lived in an area where some people had higher incomes than others also reported higher mental well-being (RR 4.5, 95% CI 2.2 to 9.1), controlling for the effects of their own income.

Conclusion

Studies of inequality and health could give more consideration to the importance of the residential domain of housing and neighbourhood to mental well-being outcomes, via the psychosocial pathway. The local spatial scale may be more important to issues of relative deprivation than previously thought, as people make local as well as broader comparisons. The ability to make upward comparisons of income within deprived areas may be beneficial to residents rather than detrimental, possibly as an indicator of area progress and ‘normality’.
Asian dust storm events are associated with an acute increase in stroke hospitalisation
Authors: Kang Jiunn-Horng , Liu Tsai-Ching , Keller Joseph , Lin Herng-Ching
Published: July 2012

Objective

Asian dust storms (ADS) are long-ranged meteorological phenomena, which are suggested to be associated with several health problems. This study aimed to investigate the risk of stroke hospitalisation following ADS events by conducting a population-based study.

Study design and setting

The authors identified 810 947 hospitalisations with an admission diagnosis of stroke during the time period between 2000 and 2009 in Taiwan. The ARIMA method (Auto-Regressive Integrated Moving Average) was used to examine the associations between ADS episodes and the daily number of stroke hospitalisations.

Results

There were 46 separate ADS episodes which resulted in a total of 135 ADS days between 2000 and 2009. The Kruskal–Wallis test revealed that there was a significant difference in the mean number of daily stroke admissions among ADS days (239.6), post-ADS days (249.2) and non-ADS days (219.7) (p<0.001). After adjusting for the time-trend effect, ambient temperature, season, SO2and CO, the authors found post-ADS days 1 and 2 to have a significantly higher number of stroke admission than non-ADS days. Post-ADS days 1 and 2 had significantly higher numbers of ischaemic but not haemorrhagic stroke admissions.

Conclusion

The authors conclude that ADS events are associated with an acute increase in stroke admission rates.
A minimal dark matter interpretation for the CRESST-II signal
Authors: Dick Rainer , Sage Frederick S.
Published: July 2012

We report on the possible interpretation of the two proposed dark matter mass values mχ=11.6 GeV and mχ=25.3 GeV from CRESST-II within the framework of the Higgs portal minimal dark matter model. We find that the higher mass value yields a suitable fit with a dark matter-Higgs coupling η/2=0.157 and a recoil cross section which is compatible with contemporary estimates of the effective Higgs–nucleon coupling. On the other hand, the lower mass solution would require a large strangeness component in the nucleon to explain the corresponding nucleon recoil cross section reported by CRESST-II.
BOX-BASKET-BALL SYSTEMS
Authors: LAM THOMAS , PYLYAVSKYY PAVLO , SAKAMOTO REIHO
Published: July 2012

Using the whurl relation of the first two authors, we define a new discrete solitonic system, which we call the box-basket-ball system, generalizing the box-ball system of Takahashi and Satsuma. In box-basket-ball systems, balls may be put either into boxes or into baskets. While boxes stay fixed, both balls and baskets get moved during time evolution. Balls and baskets behave as fermionic and bosonic particles, respectively. We classify the solitons of this system, and study their scattering.
SURFACE EVOLVER SIMULATIONS OF DROPS ON MICROPOSTS
Authors: BLOW MATTHEW L. , YEOMANS JULIA M.
Published: July 2012

An important feature in the design of superhydrophobic surfaces is their robustness against collapse from the Cassie–Baxter configuration to the Wenzel state. Upon such a transition a surface loses its properties of low adhesion and friction. We describe how to adapt the Surface Evolver algorithm to predict the parameters and mechanism of the collapse transition on posts of arbitrary shape. In particular, contributions to the free energy evaluated over the solid–liquid surface are reduced to line integrals to give good convergence. The algorithm is validated for straight, vertical and inclined, posts. Numerical results for curved posts with a horizontal section at their ends show that these are more efficient in stabilizing the Cassie state than straight posts, and identify whether the interface first depins from the post sides or the post tips.
SPECTRA OF BLACK HOLE IN DE SITTER SPACETIME WITH HIGHLY DAMPED QUASINORMAL MODES: HIGH OVERTONE CASE
Authors: LIU MOLIN , HU XUEHUI , LU JUNWANG , LU JIANBO
Published: July 2012

Motivated by recent physical interpretation on quasinormal modes presented by Maggiore [Phys. Rev. Lett. 100, 141301 (2008)], the adiabatic quantity method given by Kunstatter [Phys. Rev. Lett. 90, 161301 (2003)] is used to calculate the spectrums of a non-extremal Schwarzschild de Sitter black hole in this paper, as well as electrically charged case. According to highly damped Konoplya and Zhidenko's numerical observational results for high overtone modes [JHEP 06, 037 (2004)], we found that the asymptotic non-flat spacetime structure leads to two interesting facts: (i) near inner event horizon, the area and entropy spectrums, which are given by Aen= 8 n1πℏ, Sen= 2πn1ℏ, are equally spaced accurately. (ii) However, near outer cosmological horizon the spectrums, which are in the form of [Formula: see text], are not markedly equidistant. Finally, we also discuss the electrically charged case and find that the black holes in de Sitter spacetime have similar quantization behavior no matter with or without charge.
RADION PRODUCTION IN γe- COLLISIONS
Authors: SOA D. V. , THUY D. T. L. , THAO N. H. , THAM T. D.
Published: July 2012

We analyze the potential of Compact Linear Colliders (CLIC) based on the γe- collisions to search for the radion in the Randall–Sundrum (RS) model, where compactification radius of the extra dimension is stabilized by the radion, which is a scalar field lighter than the graviton Kaluza–Klein states. The radion production in high energy γe- colliders with the polarization of the electron beams are calculated in detail. Numerical evaluation shows that if the radion mass is not too heavy with the mass order of GeV, then the reaction can give observable cross-section in future colliders at the high degree of polarization.
DUAL LINEARIZED GRAVITY COUPLED TO BF-TYPE TOPOLOGICAL FIELD THEORIES IN D = 7
Authors: BIZDADEA CONSTANTIN , SALIU SOLANGE-ODILE , STANCIU-OPREAN LIGIA
Published: July 2012

All consistent interactions in D = 7 that can be added to one of the dual formulations of linearized gravity via a massless tensor field with the mixed symmetry (4, 1) and an Abelian BF theory with a maximal field spectrum are constructed by means of deforming the solution to the master equation on behalf of specific cohomological techniques. Among the striking features of the coupled model, we mention that the gauge transformations of all fields are deformed and the main ingredients of the gauge structure are strongly modified during the deformation procedure.
STUDY OF VECTOR MESON FRAGMENTATION USING A BROKEN SU(3) MODEL
Authors: INDUMATHI D. , SAVEETHA H.
Published: July 2012

Inclusive hadro-production in e+e- annihilation processes is examined to study the fragmentation process. A broken SU(3) model is used to determine the quark and gluon fragmentation functions of octet vector mesons, ρ and K*, in a simple way with an SU(3) breaking parameter λ. These are expressed in terms of just two light quark fragmentation functions, V(x, Q2) and γ(x, Q2) and the gluon fragmentation function Dg(x, Q2). These functions are parametrized at the low input scale of [Formula: see text], evolved through LO DGLAP evolution including charm and bottom flavor at appropriate thresholds, and fitted by comparison with data at the Z-pole. The model is extended with the introduction of a few additional parameters to include a study of singlet–octet mixing and hence ω and ϕ fragmentation. The model gives good fits to the available data for x ≳0.01, where x is the scaled energy of the hadron. The model is then applied successfully to ω, ϕ production in pp collisions at the relativistic heavy ion collider, RHIC, these data form an important baseline for the study of Quark Gluon Plasma in heavy nucleus collisions at RHIC, and also in future at the LHC.
ON ALLOMETRY RELATIONS
Authors: WEST DAMIEN , WEST BRUCE J.
Published: July 2012

There are a substantial number of empirical relations that began with the identification of a pattern in data; were shown to have a terse power-law description; were interpreted using existing theory; reached the level of "law" and given a name; only to be subsequently fade away when it proved impossible to connect the "law" with a larger body of theory and/or data. Various forms of allometry relations (ARs) have followed this path. The ARs in biology are nearly two hundred years old and those in ecology, geophysics, physiology and other areas of investigation are not that much younger. In general if X is a measure of the size of a complex host network and Y is a property of a complex subnetwork embedded within the host network a theoretical AR exists between the two when Y = aXb. We emphasize that the reductionistic models of AR interpret X and Y as dynamic variables, albeit the ARs themselves are explicitly time independent even though in some cases the parameter values change over time. On the other hand, the phenomenological models of AR are based on the statistical analysis of data and interpret X and Y as averages to yield the empirical AR: 〈Y〉 = a〈X〉b. Modern explanations of AR begin with the application of fractal geometry and fractal statistics to scaling phenomena. The detailed application of fractal geometry to the explanation of theoretical ARs in living networks is slightly more than a decade old and although well received it has not been universally accepted. An alternate perspective is given by the empirical AR that is derived using linear regression analysis of fluctuating data sets. We emphasize that the theoretical and empirical ARs are not the same and review theories "explaining" AR from both the reductionist and statistical fractal perspectives. The probability calculus is used to systematically incorporate both views into a single modeling strategy. We conclude that the empirical AR is entailed by the scaling behavior of the probability density, which is derived using the probability calculus.
GRAPHENE: JUNCTIONS AND STM SPECTRA
Authors: MAITI M. , SAHA K. , SENGUPTA K.
Published: July 2012

The presence of low-energy Dirac-like quasiparticles is one of the central features responsible for plethora of recent theoretical and experimental studies on graphene. In this review, we focus on the effect of the Dirac nature of these quasiparticles on two separate aspects. The first of these involves transport across superconducting graphene junctions with barriers of thickness d and arbitrary gate voltages V0 applied across the barrier region. The second aspect involves study of the presence of localized magnetic impurities in graphene in which we discuss the unconventional nature of Kondo physics in graphene and the tunablity of Kondo effect with a gate voltage. We also chart out the nature of scanning tunneling conductance spectra for both doped and undoped graphene in the presence of impurities and discuss the effect of Dirac nature of graphene quasiparticles on such spectra. In particular, we provide a detailed analysis of the phenomenon that that the position of the impurity in the graphene matrix plays a crucial role in determining the nature of the STM specta.
DESIGNING TUNABLE ELECTRONIC AND MAGNETIC PROPERTIES OF GRAPHENE: A THEORETICAL PERSPECTIVE
Authors: MANNA ARUN K. , PATI SWAPAN K.
Published: July 2012

The quest for novel low-dimensional materials has led to the discovery of graphene and thereafter, a tremendous attention has been paved in designing of its fascinating properties aiming in fabricating electronic devices. Using first-principles calculations, we study the structure, energetic and electronic as well as magnetic properties of graphene induced by the interactions in presence of both external and internal foreign agents in detail. We find that a variety of tunable electronic states, e.g., semiconductor-to-half-metal-to-metal and magnetic behaviors can be achieved under such hierarchical interactions and their influence. We also find that the nature and compositions of foreign substances play a key role in governing the electro-magnetic characteristics of these nanomaterials. In this review, we suggest a few routes for engineering the tunable graphene properties suitable for future electronic device applications.
SOLUTION PROCESSED GRAPHENE THIN FILMS AND THEIR APPLICATIONS IN ORGANIC SOLAR CELLS
Authors: BAULD REG , SHARIFI FARANAK , FANCHINI GIOVANNI
Published: July 2012

We present a review of the recent progresses in solution processing graphene thin films and highlight some of the uses of graphene and graphene thin films in the construction of organic solar cells. We demonstrate a simple phenomenological model to describe the relationship between sheet conductivity and transmittance in graphene films with good agreement to all of the data found in the literature. We show that graphene thin films have been proven useful in the construction and improvement of organic solar cells not only as a replacement electrode, but also as an active acceptor material, or as a counter electrode when integrated into a conducting polymer matrix.
AB INITIO STUDY OF STRUCTURAL PROPERTIES OF INTERMETALLIC COMPOUNDS PtX (X = Si, Ge, Sn AND Pb) UNDER HIGH PRESSURE
Authors: LI C. Y. , YU Z. H. , LÜ T. Q.
Published: July 2012

High pressure effect on the structural evolution properties of intermetallic compounds PtX (X = Si, Ge, Sn AND Pb ) was studied based on the first principle density functional theory. The compressibility of PtSi and PtGe under high pressure presents anisotropic behavior. The crystal stacking characteristic of the PtX (X = Si and Ge ) along the three axes may be responsible for their anisotropic axial compressibility under high pressure. The sequence of axial compressibility for PtSi is c < a < b, whereas PtGe exhibits the sequence of a < c < b. The pressure derivative of c/a was qualified to be 8.92×10-4 GPa -1 and 1.38×10-3 GPa -1 for PtSn and PtPb , respectively. The applied pressure stabilized the crystal structures of PtSn and PtPb .
ROTATIONAL BANDS AND ELECTROMAGNETIC TRANSITIONS OF SOME EVEN–EVEN NEODYMIUM NUCLEI IN PROJECTED HARTREE–FOCK MODEL
Authors: GHORUI S. K. , RAINA P. K. , RATH P. K. , SINGH A. K. , NAIK Z. , PATRA S. K. , PRAHARAJ C. R.
Published: July 2012

Rotational structures of even–even 150 – 160 Nd nuclei are studied with the self-consistent deformed Hartree–Fock (HF) and angular momentum (J) projection model. Spectra of ground band, recently observed K = 4-, K = 5- and a few more excited, positive and negative parity bands have been studied up to high spin values. Apart from these, detailed electromagnetic properties (like E2, M1 matrix elements) of all the bands have been obtained. There is substantial agreement between our model calculations and available experimental data. Predictions are made about the band structures and electromagnetic properties of these nuclei. Some 4-qasiparticle K-isomeric bands and their electromagnetic properties are predicted.
INTERNAL SYMMETRY GROUPS OF CUBIC ALGEBRAS
Authors: KERNER RICHARD , SUZUKI OSAMU
Published: July 2012

We investigate certain Z3-graded associative algebras with cubic Z3 invariant constitutive relations, introduced by one of us some time ago. The invariant forms on finite algebras of this type are given in the cases with two and three generators. We show how the Lorentz symmetry represented by the SL (2, C) group can be introduced without any notion of metric, just as the symmetry of Z3-graded cubic algebra and its constitutive relations. Its representation is found in terms of the Pauli matrices. The relationship of such algebraic constructions with quark states is also considered.
HYPERPARTICLES, TWISTORS AND ANY SPINS
Authors: SOROKIN DMITRI
Published: July 2012

In this contribution I would like to review some topics in which Jerzy Lukierski has been one of the main players and contributed over decades with many interesting and important results. We shall consider various ways in which relativistic particles can be endowed with spin degrees of freedom with the use of twistor-like variables and supersymmetrization, which upon quantization lead either to higher-spin fields (in D > 3) or to anions (in D = 3).
SUPERSYMMETRIC HOLST ACTION WITH MATTER COUPLING AND PARITY VIOLATION
Authors: SZCZACHOR MICHAŁ
Published: July 2012

A general construction of the Holst action is discussed. Based on this, the N = 1, 2, 4, 8 supergravities and N = 1 supergravities with matter coupling are presented. It is shown that in all these cases the Immirzi parameter does not influence the field equations. The construction ensures that the theory is invariant under supersymmetry as well as gauge transformations, but the Holst extension breaks parity.
The severity of shock is associated with impaired rates of net alveolar fluid clearance in clinical acute lung injury
Authors: Zeyed Yosaf F. , Bastarache Julie A. , Matthay Michael A. , Ware Lorraine B.
Published: July 2012

The rate of alveolar fluid clearance (AFC) is associated with mortality in clinical acute lung injury (ALI). Patients with ALI often develop circulatory shock, but how shock affects the rate of AFC is unknown. To determine the effect of circulatory shock on the rate of AFC in patients with ALI, the rate of net AFC was measured in 116 patients with ALI by serial sampling of pulmonary edema fluid. The primary outcome was the rate of AFC in patients with shock compared with those without shock. We also tested the effects of shock severity and bacteremia. Patients with ALI and shock ( n = 86) had significantly slower rates of net AFC compared with those without shock ( n = 30, P = 0.03), and AFC decreased significantly as the number of vasopressors increased. Patients with positive blood cultures ( n = 21) had slower AFC compared with patients with negative blood cultures ( n = 96, P = 0.023). In addition, the edema fluid-to-plasma protein ratio, an index of alveolar-capillary barrier permeability, was highest in patients requiring the most vasopressors ( P < 0.05). Patients with ALI complicated by circulatory shock and bacteremia had slower rates of AFC compared with patients without shock or bacteremia. An impaired capacity to reabsorb alveolar edema fluid may contribute to high mortality among patients with sepsis-induced ALI. These findings also suggest that vasopressor use may be a marker of alveolar-capillary barrier permeability in ALI and provide justification for new therapies that enhance alveolar epithelial and endothelial barrier integrity in ALI, particularly in patients with shock.
Does the ΔF508-CFTR mutation induce a proinflammatory response in human airway epithelial cells?
Authors: Hampton Thomas H. , Ballok Alicia E. , Bomberger Jennifer M. , Rutkowski Melanie R. , Barnaby Roxanna , Coutermarsh Bonita , Conejo-Garcia José R. , O'Toole George A. , Stanton Bruce A.
Published: July 2012

In the clinical setting, mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene enhance the inflammatory response in the lung to Pseudomonas aeruginosa ( P. aeruginosa ) infection. However, studies on human airway epithelial cells in vitro have produced conflicting results regarding the effect of mutations in CFTR on the inflammatory response to P. aeruginosa, and there are no comprehensive studies evaluating the effect of P. aeruginosa on the inflammatory response in airway epithelial cells with the ΔF508/ΔF508 genotype and their matched CF cell line rescued with wild-type (wt)-CFTR. CFBE41o- cells (ΔF508/ΔF508) and CFBE41o- cells complemented with wt-CFTR (CFBE-wt-CFTR) have been used extensively as an experimental model to study CF. Thus the goal of this study was to examine the effect of P. aeruginosa on gene expression and cytokine/chemokine production in this pair of cells. P. aeruginosa elicited a more robust increase in cytokine and chemokine expression (e.g., IL-8, CXCL1, CXCL2 and TNF-α) in CFBE-wt-CFTR cells compared with CFBE-ΔF508-CFTR cells. These results demonstrate that CFBE41o- cells complemented with wt-CFTR mount a more robust inflammatory response to P. aeruginosa than CFBE41o-ΔF508/ΔF508-CFTR cells. Taken together with other published studies, our data demonstrate that there is no compelling evidence to support the view that mutations in CFTR induce a hyperinflammatory response in human airway epithelial cells in vivo . Although the lungs of patients with CF have abundant levels of proinflammatory cytokines and chemokines, because the lung is populated by immune cells and epithelial cells there is no way to know, a priori, whether airway epithelial cells in the CF lung in vivo are hyperinflammatory in response to P. aeruginosa compared with non-CF lung epithelial cells. Thus studies on human airway epithelial cell lines and primary cells in vitro that propose to examine the effect of mutations in CFTR on the inflammatory response to P. aeruginosa have uncertain clinical significance with regard to CF.
Sleep Stage Classification Using Unsupervised Feature Learning
Authors: Längkvist Martin , Karlsson Lars , Loutfi Amy
Published: July 2012

Most attempts at training computers for the difficult and time-consuming task of sleep stage classification involve a feature extraction step. Due to the complexity of multimodal sleep data, the size of the feature space can grow to the extent that it is also necessary to include a feature selection step. In this paper, we propose the use of an unsupervised feature learning architecture called deep belief nets (DBNs) and show how to apply it to sleep data in order to eliminate the use of handmade features. Using a postprocessing step of hidden Markov model (HMM) to accurately capture sleep stage switching, we compare our results to a feature-based approach. A study of anomaly detection with the application to home environment data collection is also presented. The results using raw data with a deep architecture, such as the DBN, were comparable to a feature-based approach when validated on clinical datasets.
Asymptotic Solutions of Singular Perturbed Problems with an Instable Spectrum of the Limiting Operator
Authors: Kalimbetov Burkhan T. , Temirbekov Marat A. , Khabibullayev Zhanibek O.
Published: July 2012

The regularization method is applied for the construction of algorithm for an asymptotical solution for linear singular perturbed systems with the irreversible limit operator. The main idea of this method is based on the analysis of dual singular points of investigated equations and passage in the space of the larger dimension, what reduces to study of systems of first‐order partial differential equations with incomplete initial data.
Evidence for Inhibitory Effects of Flupirtine, a Centrally Acting Analgesic, on Delayed Rectifier K+Currents in Motor Neuron-Like Cells
Authors: Wu Sheng-Nan , Hsu Ming-Chun , Liao Yu-Kai , Wu Fang-Tzu , Jong Yuh-Jyh , Lo Yi-Ching
Published: July 2012

Flupirtine (Flu), a triaminopyridine derivative, is a centrally acting, non-opiate analgesic agent. In this study, effects of Flu onK+currents were explored in two types of motor neuron-like cells. Cell exposure to Flu decreased the amplitude of delayed rectifierK+current (IK(DR)) with a concomitant raise in current inactivation in NSC-34 neuronal cells. The dissociation constant for Flu-mediated increase ofIK(DR)inactivation rate was about 9.8 μM. Neither linopirdine (10 μM), NMDA (30 μM), nor gabazine (10 μM) reversed Flu-induced changes inIK(DR)inactivation. Addition of Flu shifted the inactivation curve ofIK(DR)to a hyperpolarized potential. Cumulative inactivation forIK(DR)was elevated in the presence of this compound. Flu increased the amplitude of M-typeK+current (IK(M)) and produced a leftward shift in the activation curve ofIK(M). In another neuronal cells (NG108-15), Flu reducedIK(DR)amplitude and enhanced the inactivation rate ofIK(DR). The results suggest that Flu acts as an open-channel blocker of delayed-rectifierK+channels in motor neurons. Flu-induced block ofIK(DR)is unlinked to binding to NMDA or GABA receptors and the effects of this agent onK+channels are not limited to its action on M-typeK+channels.
Neuroleptic Malignant Syndrome Caused by a Combination of Carbamazepine and Amitriptyline
Authors: Janati A. Bruce , ALGhasab Naif , Osman Aboubaker
Published: July 2012

A 32-year-old female, with a history of secondarily-generalized convulsive epilepsy, mental retardation, and a psychiatric illness, developed neuroleptic malignant syndrome while receiving carbamazepine and amitriptyline concurrently. We hypothesize that the addition of amitriptyline to carbamazepine caused a decrease in the serum level of carbamazepine, resulting in NMS. We conclude that combination therapy with carbamazepine and amitriptyline should be avoided in patients who are predisposed to NMS. The purpose of this paper is to warn physicians against combination therapy with carbamazepine and tricyclic antidepressants which may be conducive to neuroleptic malignant syndrome in susceptible patients.
Projective Synchronization of N‐Dimensional Chaotic Fractional‐Order Systems via Linear State Error Feedback Control
Authors: Xin Baogui , Chen Tong
Published: July 2012

Based on linear feedback control technique, a projective synchronization scheme of N‐dimensional chaotic fractional‐order systems is proposed, which consists of master and slave fractional‐order financial systems coupled by linear state error variables. It is shown that the slave system can be projectively synchronized with the master system constructed by state transformation. Based on the stability theory of linear fractional order systems, a suitable controller for achieving synchronization is designed. The given scheme is applied to achieve projective synchronization of chaotic fractional‐order financial systems. Numerical simulations are given to verify the effectiveness of the proposed projective synchronization scheme.
Pott's Spine with Bilateral Psoas Abscesses
Authors: Masavkar Sanjeevani , Shanbag Preeti , Inamdar Prithi
Published: July 2012

A high degree of suspicion and appropriate imaging studies are required for the early diagnosis of Pott’s spine. We describe a 4-year-old boy with Pott’s disease of the lumbar spine with bilateral psoas abscesses. The child responded to conservative treatment with antituberculous treatment and ultrasonographically guided percutaneous drainage of the abscesses.
Minimally Invasive Thoracic Corpectomy: Surgical Strategies for Malignancy, Trauma, and Complex Spinal Pathologies
Authors: Lall Rohan R. , Smith Zachary A. , Wong Albert P. , Miller Daniel , Fessler Richard G.
Published: July 2012

The rapid expansion of minimally invasive techniques for corpectomy in the thoracic spine provides promise to redefine treatment options in this region. Techniques have evolved permitting anterior, lateral, posterolateral, and midline posterior corpectomy in a minimally invasive fashion. We review the numerous techniques that have been described, including thoracoscopy, tubular retraction, and various instrumentation techniques. Minimally invasive techniques are compared to their open predecessors from a technical and complication standpoint. Advantages and disadvantages of different approaches are also considered, with an emphasis on surgical strategies and nuance.
Exercise for Adolescents with Depressive Disorders: A Feasibility Study
Authors: Dopp Richard R. , Mooney Ann J. , Armitage Roseanne , King Cheryl
Published: July 2012

Objectives. Adolescence is associated with increased depressive symptoms and decreased aerobic exercise, yet the relationship between exercise and clinical depression among adolescents requires further examination. This study assessed the feasibility of a 12-week intervention designed to increase exercise for adolescents with depressive disorders: Will a teenager with depression exercise?Methods. Participants were 13 adolescents with depression reporting low levels of aerobic exercise. They completed a 12-week intervention (15 supervised exercise sessions and 21 independent sessions). Exercise was measured through the aerobic exercise Questionnaire, actigraphy, and heart-rate monitoring. Depression was measured with the Children’s Depression Rating Scale, Revised, and Quick Inventory of Depressive Symptomatology, Self-Report.Results. All participants who started the intervention completed the protocol, attending all supervised exercise sessions. Actigraphy verified 81% adherence to the protocol’s independent sessions. Analysis of secondary outcomes showed a significant increase in exercise levels and a significant decrease in depression severity. Initially, ten participants were overweight or obese, and three were healthy weight. After 12 weeks of exercise, the number of participants in the healthy-weight category doubled.Conclusions. Adolescents suffering from depression can complete a rigorous protocol requiring structured increases in aerobic exercise. Participants showed significant increases in exercise, and significant decreases in depressive symptoms.
Gearbox Fault Features Extraction Using Vibration Measurements and Novel Adaptive Filtering Scheme
Authors: Ibrahim Ghalib R. , Albarbar A.
Published: July 2012

Vibration signals measured from a gearbox are complex multicomponent signals, generated by tooth meshing, gear shaft rotation, gearbox resonance vibration signatures, and a substantial amount of noise. This paper presents a novel scheme for extracting gearbox fault features using adaptive filtering techniques for enhancing condition features, meshing frequency sidebands. A modified least mean square (LMS) algorithm is examined and validated using only one accelerometer, instead of using two accelerometers in traditional arrangement, as the main signal and a desired signal is artificially generated from the measured shaft speed and gear meshing frequencies. The proposed scheme is applied to a signal simulated from gearbox frequencies with a numerous values of step size. Findings confirm that 10−5 step size invariably produces more accurate results and there has been a substantial improvement in signal clarity (better signal-to-noise ratio), which makes meshing frequency sidebands more discernible. The developed scheme is validated via a number of experiments carried out using two-stage helical gearbox for a healthy pair of gears and a pair suffering from a tooth breakage with severity fault 1 (25% tooth removal) and fault 2 (50% tooth removal) under loads (0%, and 80% of the total load). The experimental results show remarkable improvements and enhance gear condition features. This paper illustrates that the new approach offers a more effective way to detect early faults.
Multidimensional Scaling Applied to Histogram-Based DNA Analysis
Authors: Costa António C. , Tenreiro Machado J. A. , Quelhas Maria Dulce
Published: July 2012

This paper aims to study the relationships between chromosomal DNA sequences of twenty species. We propose a methodology combining DNA-based word frequency histograms, correlation methods, and an MDS technique to visualize structural information underlying chromosomes (CRs) and species. Four statistical measures are tested (Minkowski, Cosine, Pearson product-moment, and Kendallτrank correlations) to analyze the information content of 421 nuclear CRs from twenty species. The proposed methodology is built on mathematical tools and allows the analysis and visualization of very large amounts of stream data, like DNA sequences, with almost no assumptions other than the predefined DNA “word length.” This methodology is able to produce comprehensible three-dimensional visualizations of CR clustering and related spatial and structural patterns. The results of the four test correlation scenarios show that the high-level information clusterings produced by the MDS tool are qualitatively similar, with small variations due to each correlation method characteristics, and that the clusterings are a consequence of the input data and not method’s artifacts.
Welding Diagnostics by Means of Particle Swarm Optimization and Feature Selection
Authors: Mirapeix J. , García-Allende P. B. , Conde O. M. , Lopez-Higuera J. M. , Cobo A.
Published: July 2012

In a previous contribution, a welding diagnostics approach based on plasma optical spectroscopy was presented. It consisted of the employment of optimization algorithms and synthetic spectra to obtain the participation profiles of the species participating in the plasma. A modification of the model is discussed here: on the one hand the controlled random search algorithm has been substituted by a particle swarm optimization implementation. On the other hand a feature selection stage has been included to determine those spectral windows where the optimization process will take place. Both experimental and field tests will be shown to illustrate the performance of the solution that improves the results of the previous work.
Hopf Bifurcation Analysis and Anticontrol of Hopf Circles of the Rössler‐Like System
Authors: Wu Ranchao , Li Xiang
Published: July 2012

A new Rössler‐like system is constructed by the linear feedback control scheme in this paper. As well, it exhibits complex dynamical behaviors, such as bifurcation, chaos, and strange attractor. By virtue of the normal form theory, its Hopf bifurcation and stability are investigated in detail. Consequently, the stable periodic orbits are bifurcated. Furthermore, the anticontrol of Hopf circles is achieved between the new Rössler‐like system and the original Rössler one via a modified projective synchronization scheme. As a result, a stable Hopf circle is created in the controlled Rössler system. The corresponding numerical simulations are presented, which agree with the theoretical analysis.
Small-Molecule Inhibitors of GSK-3: Structural Insights and Their Application to Alzheimer's Disease Models
Authors: Kramer Thomas , Schmidt Boris , Lo Monte Fabio
Published: July 2012

The world health organization (WHO) estimated that 18 million people are struck by Alzheimer's disease (AD). The USA, France, Germany, and other countries launched major programmes targeting the identification of risk factors, the improvement of caretaking, and fundamental research aiming to postpone the onset of AD. The glycogen synthase kinase 3 (GSK-3) is implicated in multiple cellular processes and has been linked to the pathogenesis of several diseases including diabetes mellitus, cancer, and AD. Inhibition of GSK-3 leads to neuroprotective effects, decreasedβ-amyloid production, and a reduction in tau hyperphosphorylation, which are all associated with AD. Various classes of small molecule GSK-3 inhibitors have been published in patents and original publications. Herein, we present a comprehensive summary of small molecules reported to interact with GSK-3. We illustrate the interactions of the inhibitors with the active site. Furthermore, we refer to the biological characterisation in terms of activity and selectivity for GSK-3, elucidatein vivostudies and pre-/clinical trials.
Comparison of Disk Diffusion and Etest Methods to Determine the Susceptibility ofStaphylococcus aureusCirculating in Riyadh, Saudi Arabia to Fusidic Acid
Authors: Somily Ali M. , Peaper David R. , Paintsil Elijah , Murray Thomas S.
Published: July 2012

Fusidic acid is a common therapy for staphylococcal infections in Saudi Arabia, but reports have suggested high rates of resistance among clinical isolates. Susceptibility testing ofS. aureusto fusidic acid is further complicated by the lack of consensus on mean inhibitory concentrations (MIC) and disk diffusion cutoffs to determine resistance. The purpose of this study was to determine the correlation between disk diffusion and Etest determined MIC susceptibility results in clinical isolates ofS. aureusfrom a large academic hospital in Riyadh, Saudi Arabia. Our data demonstrate excellent correlation between Etest determined MIC and disk diffusion susceptibility data, using either previously proposed zone sizes of ≥21 mm as susceptible and ≤18 mm as resistant or the EUCAST recommended zone size of ≤24 mm for resistance, in an area with relatively high rates of fusidic acid resistance.
Relationship between Synthesis Conditions and Photocatalytic Activity of Nanocrystalline TiO2
Authors: Han Yosep , Kim Hyung-Seok , Kim Hyunjung
Published: July 2012

The degradation efficiency of methylene blue by TiO2 nanoparticles, which were synthesized under different synthesis conditions (i.e., molar ratio of water and titanium tetraisopropoxide (TTIP), pH, and calcination temperature) in a sol‐gel process, was systematically investigated. The results showed that increasing the molar ratio of water and TTIP led to the enhanced photocatalytic activity of TiO2 nanoparticles, which were likely attributed to the increased specific surface area of TiO2 nanoparticles synthesized with high molar ratio. The results were supported by the relative increase in the size of interaggregated pores of the aggregated TiO2 nanoparticles. The best photocatalytic activity of TiO2 nanoparticles was observed at acidic synthesis conditions; however, the results were not consistent with physical properties for the crystallinity and the crystallite size of TiO2 nanoparticles but rather explained by the presence of abundant hydroxyl groups and water molecules existing on the surface of TiO2 under acidic synthesis environments. Furthermore, methylene blue degradation experiments revealed that the photocatalytic activity of TiO2 nanoparticles was maximized at the calcination temperature of 700°C. The trend was likely due to the combined effect of the anatase crystallinity which showed the highest value at 700°C and the crystallite size/specific surface area which did not excessively increase up to 700°C.