bluuebunny/crossref_metadata_2025 huggingface dataset:
PROBING COMPLEX NETWORKS FROM MEASURED TIME SERIES
Authors: HUANG LIANG , LAI YING-CHENG , HARRISON MARY ANN F.
Published: November 2012

We propose a method to detect nodes of relative importance, e.g. hubs, in an unknown network based on a set of measured time series. The idea is to construct a matrix characterizing the synchronization probabilities between various pairs of time series and examine the components of the principal eigenvector. We provide a heuristic argument indicating the existence of an approximate one-to-one correspondence between the components and the degrees of the nodes from which measurements are obtained. The striking finding is that such a correspondence appears to be quite robust, which holds regardless of the detailed node dynamics and of the network topology. Our computationally efficient method thus provides a general means to address the important problem of network detection, with potential applications in a number of fields.
CHAOTIC DIFFUSION IN MULTIDIMENSIONAL CONSERVATIVE MAPS
Authors: CINCOTTA PABLO M. , GIORDANO CLAUDIA M.
Published: November 2012

In the present paper, we provide results and discussions concerning the processes that lead to local and global chaotic diffusion in the phase space of multidimensional conservative systems. We investigate and provide a measure of the extent of the domain over which diffusion may occur. All these issues are thoroughly discussed by dealing with a multidimensional conservative map that would be representative of the dynamics of a resonance interaction, which is an important mechanism in many dynamical systems.
COMPLEX DYNAMICS OF SEMICONDUCTOR QUANTUM DOT LASERS SUBJECT TO DELAYED OPTICAL FEEDBACK
Authors: OTTO CHRISTIAN , GLOBISCH BJÖRN , LÜDGE KATHY , SCHÖLL ECKEHARD , ERNEUX THOMAS
Published: November 2012

We study a five-variable electron-hole model for a quantum-dot (QD) laser subject to optical feedback. The model includes microscopically computed Coulomb scattering rates. We consider the case of a low linewidth enhancement factor and a short external cavity. We determine the bifurcation diagram of the first three external cavity modes and analyze their bifurcations. The first Hopf bifurcation marks the critical feedback rate below which the laser is stable. We derive an analytical approximation for this critical feedback rate that is proportional to the damping rate of the relaxation oscillations (ROs) and inversely proportional to the linewidth enhancement factor. The damping rate is described in terms of the carrier lifetimes. They depend on the specific band structure of the QD device and they are computed numerically.
A KICKED EPIDEMIC SIRS MODEL
Authors: PALADINI F. , RENNA I. , RENNA L.
Published: November 2012

A discrete-time deterministic epidemic model is proposed with the aim of reproducing the behavior observed in the incidence of real infectious diseases, such as oscillations and irregularities. For this purpose, we introduce, in a naïve discrete-time SIRS model, seasonal variability (i) in the loss of immunity and (ii) in the infection probability, modeled by sequences of kicks. Effects of a variable population size (assumed as logistic) are also analyzed. Restrictive assumptions are made on the parameters of the models, in order to guarantee that the transitions are determined by true probabilities, so that comparisons with stochastic discrete-time previsions can be also provided. Numerical simulations show that the characteristics of real infectious diseases can be adequately modeled.
CHAOTIC BEHAVIOR IN A FRACTIONAL-ORDER SYSTEM CONTAINING A CONTINUOUS ORDER-DISTRIBUTION
Authors: HARTLEY TOM T. , LORENZO CARL F.
Published: November 2012

This paper discusses the fractional dynamics, and the bifurcation behavior, of a specific nonlinear system that contains a continuous order-distribution. The dynamics of the system are predicted using the describing-function method. General approximation methods are then derived for the continuous order-distribution component. The system is simulated using these approximations, and the results compared with the describing-function predictions. This is believed to be the first observation of chaos in a system with continuous order-distribution.
DEGENERATIONS OF RICCI-FLAT CALABI–YAU MANIFOLDS
Authors: RONG XIAOCHUN , ZHANG YUGUANG
Published: November 2012

This paper is a sequel to [Continuity of extremal transitions and flops for Calabi–Yau manifolds, J. Differential Geom.89 (2011) 233–270]. We further investigate the Gromov–Hausdorff convergence of Ricci-flat Kähler metrics under degenerations of Calabi–Yau manifolds. We extend Theorem 1.1 in [Continuity of extremal transitions and flops for Calabi–Yau manifolds, J. Differential Geom.89 (2011) 233–270] by removing the condition on existence of crepant resolutions for Calabi–Yau varieties.
RELATIVE RUAN AND GROMOV–TAUBES INVARIANTS OF SYMPLECTIC 4-MANIFOLDS
Authors: DORFMEISTER JOSEF G. , LI TIAN-JUN
Published: November 2012

We define relative Ruan invariants that count embedded connected symplectic submanifolds which contact a fixed symplectic hypersurface V in a symplectic 4-manifold (X, ω) at prescribed points with prescribed contact orders (in addition to insertions on X\V). We obtain invariants of the deformation class of (X, V, ω). Two large issues must be tackled to define such invariants: (1) curves lying in the hypersurface V and (2) genericity results for almost complex structures constrained to make V pseudo-holomorphic (or almost complex). Moreover, these invariants are refined to take into account rim-tori decompositions. In the latter part of the paper, we extend the definition to disconnected submanifolds and construct relative Gromov–Taubes invariants.
ENTROPY ESTIMATES AND LARGE-TIME BEHAVIOR OF SOLUTIONS TO A FOURTH-ORDER NONLINEAR DEGENERATE EQUATION
Authors: MIN LIHUA , YANG XIAOPING , GUI CHANGFENG
Published: November 2012

The main aim of this paper is to give some theoretical analysis for a nonlinear fourth-order degenerate equation related to image processing, with homogeneous Neumann and no-flux boundary conditions. The asymptotic behavior of solutions to the equation is discussed in the paper using the entropy dissipation method. We firstly derive some entropy estimates via the algebraic approach, and present a polynomial decay of an entropy. As a result, we prove solutions of the equation eventually converge to equilibrium, which can help us understand the model in greater depth. To the best of our knowledge, this is the first result on the long-time behavior of the fourth-order model in image processing.
AN ITERATIVE ALGORITHM FOR A CLASS OF NONLINEAR INTEGER BILEVEL PROGRAMMING PROBLEMS WITH BOX CONSTRAINTS
Authors: Dahiya Kalpana , Sharma Vikas , Verma Vanita
Published: November 2012

The bilevel programming problem is a leader–follower game in which two players try to maximize their own objective functions over a common constraint region. This paper discusses an integer nonlinear bilevel programming problem with box constraints by exploiting the quasimonotone character of the indefinite quadratic fractional function, considered as leader's objective. By making use of the duality theory, given nonlinear bilevel programming problem is transformed into single level programming problem. Various cuts have been discussed in this paper which successively rank and scan all integer feasible points of the single level programming problem in the decreasing value of objective function. An iterative algorithm is proposed, which by making use of these cuts repeatedly, solves the problem.
ZERO DIVISOR GRAPHS OF LATTICES AND PRIMAL IDEALS
Authors: Joshi Vinayak , Waphare B. N. , Pourali H. Y.
Published: November 2012

In this paper, we introduce the concepts of primal and weakly primal ideals in lattices. Further, the diameter of the zero divisor graph of a lattice with respect to a non-primal ideal is determined.
EXISTENCE AND STABILITY OF ALMOST PERIODIC SOLUTIONS FOR NICHOLSON'S BLOWFLIES MODELS WITH PATCH STRUCTURE AND LINEAR HARVESTING TERMS OB TIME SCALES
Authors: Li Yongkun , Yang Li
Published: November 2012

In this paper, by constructing a contraction mapping and using the time scale calculus theory and the Lyapunov function method, we obtain some sufficient conditions for the existence and stability of almost periodic solutions for a class of Nicholson's blowflies models with patch structure and linear harvesting terms on time scales. The results of this paper are completely new. Moreover, we present an illustrative example and numerical simulation to show the effectiveness of obtained results.
ON WEAK ZIP SKEW POLYNOMIAL RINGS
Authors: Mohammadi R. , Moussavi A. , Zahiri M.
Published: November 2012

We introduce the notion of nil(α, δ)-compatible rings which is a generalization of reduced rings and (α, δ)-compatible rings. In [Ore extensions of weak zip rings, Glasgow Math. J.51 (2009) 525–537] Ouyang introduces the notion of right (respectively, left) weak zip rings and proved that, a ring R is right (respectively, left) weak zip if and only if the skew polynomial ring R[x; α, δ] is right (respectively, left) weak zip, when R is (α, δ)-compatible and reversible. We extend this result to the more general situation that, when R has (α, δ)-condition and quasi-IFP, then nil (R)[x; α, δ] = nil (R[x; α, δ]); and R is right (respectively, left) weak zip if and only if the skew polynomial ring R[x; α, δ] is right (respectively, left) weak zip.
STRUCTURAL AND DIELECTRIC PROPERTIES OF GLASSES IN THE SYSTEM TeO2–CaCu3Ti4O12
Authors: THOMAS P. , VARMA K. B. R.
Published: November 2012

The glasses in the system (100 - x) TeO2 –x CaCu3Ti4O12 , (x = 0.25 mol. % to 3 mol.%) were fabricated. The color varied from olive green to brown as the CaCu3Ti4O12 (CCTO) content increased in TeO2 matrix. The X-ray powder diffraction and differential scanning calorimetric analyses that were carried out on the as-quenched samples confirmed their amorphous and glassy nature respectively. The dielectric constant and loss in the 100 Hz–1 MHz frequency range were monitored as a function of temperature (50–400°C). The dielectric constant [Formula: see text] and the loss (D) increased as the CCTO content increased in TeO2 at all the frequencies and temperatures under investigation. Further, the [Formula: see text] and D were found to be frequency-independent in the 50–200°C temperature range. The value obtained for the loss at 1 MHz was 0.0019 which was typical of low loss materials, and exhibited near constant loss (NCL) in the 100 Hz–1 MHz frequency range. The electrical relaxation was rationalized using the electric modulus formalism. These glasses may be of considerable interest as substrates for high frequency circuit elements in conventional semiconductor industries owing to their high thermal stability.
Remagnetization and chemical alteration of sedimentary rocks
Authors: Elmore R. D. , Muxworthy A. R. , Aldana M.
Published: November 2012

Chemical remagnetization is a very common phenomenon in sedimentary rocks and developing a greater understanding of the mechanisms has several benefits. Acquisition of a secondary magnetization is usually tangible evidence of a diagenetic event that can be dated by isolation of the chemical remanent magnetization and comparison of the pole position to the apparent polar wander path. This can be important because diagenetic investigations are frequently limited by the difficulty in constraining the time frames in which most past events have occurred. Remagnetization can commonly obscure a primary magnetization; developing a better understanding of remagnetization could improve our ability to uncover primary magnetizations. Many chemical remagnetization mechanisms have been proposed, including those associated with chemical alteration by a number of different fluids (orogenic, basinal and hydrocarbons), burial diagenetic processes (clay diagenesis and maturation of organic matter) or other processes. This paper summarizes our current knowledge of these chemical remagnetization mechanisms, with a focus on examples where there is a connection with chemical alteration.
Claudins and the Kidney
Authors: Hou Jianghui , Rajagopal Madhumitha , Yu Alan S.L.
Published: November 2012

Claudins are tight junction membrane proteins that regulate paracellular permeability of renal epithelia to small ions, solutes, and water. Claudins interact within the cell membrane and between neighboring cells to form tight junction strands and constitute both the paracellular barrier and the pore. The first extracellular domain of claudins is thought to be the pore-lining domain and contains the determinants of charge selectivity. Multiple claudins are expressed in different nephron segments; such differential expression likely determines the permeability properties of each segment. Recent evidence has identified claudin-2 as constituting the cation-reabsorptive pathway in the proximal tubule; claudin-14, -16, and -19 as forming a complex that regulates calcium transport in the thick ascending limb of the loop of Henle; and claudin-4, -7, and -8 as determinants of collecting duct chloride permeability. Mutations in claudin-16 and -19 cause familial hypercalciuric hypomagnesemia with nephrocalcinosis. The roles of other claudins in kidney diseases remain to be fully elucidated.
SMB myosin heavy chain knockout enhances tonic contraction and reduces the rate of force generation in ileum and stomach antrum
Authors: Huang Qian , Babu Gopal J. , Periasamy Muthu , Eddinger Thomas J.
Published: November 2012

The role of SMA and SMB smooth muscle myosin heavy chain (MHC) isoforms in tonic and phasic contractions was studied in phasic (longitudinal ileum and stomach circular antrum) and tonic (stomach circular fundus) smooth muscle tissues of SMB knockout mice. Knocking out the SMB MHC gene eliminated SMB MHC protein expression and resulted in upregulation of the SMA MHC protein without altering the total MHC protein level. Switching from SMB to SMA MHC protein expression decreased the rate of the force transient and increased the sustained tonic force in SMB(−/−) ileum and antrum with high potassium (KPSS) but not with carbachol (CCh) stimulation. The increased tonic contraction under the depolarized condition was not through changes in second messenger signaling pathways (PKC/CPI-17 or Rho/ROCK signaling pathway) or LC20 phosphorylation. Biochemical analyses showed that the expression of contractile regulatory proteins (MLCK, MLCP, PKCδ, and CPI-17) did not change significantly in tissues tested except for PKCα protein expression being significantly decreased in the SMB(−/−) antrum. However, specifically activating PKCα with phorbol dibutyrate (PDBu) was not significantly different in knockout and wild-type tissues, with total force being a fraction of the force generation with KPSS or CCh stimulation in SMB(−/−) ileum and antrum. Taken together, these data show removing the SMB MHC protein expression with a compensatory increase in the SMA MHC protein results in enhanced sustained KPSS-induced tonic contraction with a reduced rate of force generation in these phasic tissues.
Isotopic and modeling investigation of long-term protein turnover in rat tissues
Authors: Poupin Nathalie , Huneau Jean-François , Mariotti François , Tomé Daniel , Bos Cécile , Fouillet Hélène
Published: November 2012

Fractional synthesis rates (FSR) of tissue proteins (P) are usually measured using labeled amino acid (AA) tracer methods over short periods of time under acute, particular conditions. By combining the long-term and non-steady-state15N labeling of AA and P tissue fractions with compartmental modeling, we have developed a new isotopic approach to investigate the degree of compartmentation of P turnover in tissues and to estimate long-term FSR values under sustained and averaged nutritional and physiological conditions. We measured the rise-to-plateau kinetics of nitrogen isotopic enrichments (δ15N) in the AA and P fractions of various tissues in rats for 2 mo following a slight increase in diet δ15N. Using these δ15N kinetics and a numerical method based on a two-compartment model, we determined reliable FSR estimates for tissues in which P turnover is adequately represented by such a simple precursor-product model. This was the case for kidney, liver, plasma, and muscle, where FSR estimates were 103, 101, 58, and 11%/day, respectively. Conversely, we identified tissues, namely, skin and small intestine, where P turnover proved to be too complex to be represented by a simple two-compartment model, evidencing the higher level of subcompartmentation of the P and/or AA metabolism in these tissues. The present results support the value of this new approach in gaining cognitive and practical insights into tissue P turnover and propose new and integrated FSR values over all individual precursor AA and all diurnal variations in P kinetics.
Urine concentration in the diabetic mouse requires both urea and water transporters
Authors: Ilori Titilayo O. , Blount Mitsi A. , Martin Christopher F. , Sands Jeff M. , Klein Janet D.
Published: November 2012

The regulation of the inner medullary collecting duct (IMCD) urea transporters (UT-A1, UT-A3) and aquaporin-2 (AQP2) and their interactions in diabetic animals is unknown. We investigated whether the urine concentrating defect in diabetic animals was a function of AQP2, the UT-As, or both transporters. UT-A1/UT-A3 knockout (UT-A1/A3 KO) mice produce dilute urine. We gave wild-type (WT) and UT-A1/A3 KO mice vasopressin via minipump for 7 days. In WT mice, vasopressin increased urine osmolality from 3,000 to 4,550 mosmol/kgH2O. In contrast, urine osmolality was low (800 mosmol/kgH2O) in the UT-A1/A3 KOs and remained low following vasopressin. Surprisingly, AQP2 protein abundance increased in UT-A1/A3 KO (114%) and WT (92%) mice. To define the role of UT-A1 and UT-A3 in the diabetic responses, WT and UT-A1/A3 KO mice were injected with streptozotocin (STZ). UT-A1/A3 KO mice showed only 40% survival at 7 days post-STZ injection compared with 70% in WT. AQP2 did not increase in the diabetic UT-A1/A3 KO mice compared with a 133% increase in WT diabetic mice. Biotinylation studies in rat IMCDs showed that membrane accumulation of UT-A1 increased by 68% in response to vasopressin in control rats but was unchanged by vasopressin in diabetic rat IMCDs. We conclude that, even with increased AQP2, UT-A1/UT-A3 is essential to optimal urine concentration. Furthermore, UT-A1 may be maximally membrane associated in diabetic rat inner medulla, making additional stimulation by vasopressin ineffective.
Vasopressin inhibits apoptosis in renal collecting duct cells
Authors: Miller R. Lance , Sandoval Pablo C. , Pisitkun Trairak , Knepper Mark A. , Hoffert Jason D.
Published: November 2012

The peptide hormone arginine vasopressin (AVP) plays a critical role in regulating salt and water transport in the mammalian kidney. Recent studies have also demonstrated that AVP can promote cell survival in neuronal cells through V1 receptors. The current study addresses whether AVP can inhibit apoptosis in kidney collecting duct cells via V2 receptors and also explores the downstream signaling pathways regulating this phenomenon. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling analysis and caspase cleavage assays demonstrated that 1-desamino-8-d-arginine vasopressin (dDAVP) inhibited apoptosis induced by various agents (staurosporine, actinomycin D, and cycloheximide) in cultured mouse cortical collecting duct cells (mpkCCD). Incubation with dDAVP also inhibited apoptosis induced by the phosphatidylinositol 3-kinase (PI3K) pathway inhibitor LY294002, suggesting that the antiapoptotic effects of dDAVP are largely independent of PI3K signaling. The V2 receptor antagonist SR121463 completely abolished the antiapoptotic effects of dDAVP. In addition, incubation with 8-cpt-cAMP, a cell-permeable analog of cAMP, reproduced the antiapoptotic effects of dDAVP. Both dDAVP and 8-cpt-cAMP increased phosphorylation of proapoptotic Bcl-2 family members Bad and Bok. Bad phosphorylation at Ser-112 and Ser-155 is known to inhibit its proapoptotic activity. Preincubation with H89 blocked dDAVP-induced phosphorylation of both Bad and Bok, suggesting dependence on protein kinase A (PKA). This study provides evidence that AVP can inhibit apoptosis through the V2 receptor and downstream cAMP-mediated pathways in mammalian kidney. The antiapoptotic action of AVP may be relevant to a number of physiological and pathophysiological conditions including osmotic tolerance in the inner medulla, escape from AVP-induced antidiuresis, and polycystic kidney disease.
Diallyl trisulfide and diallyl disulfide ameliorate cardiac dysfunction by suppressing apoptotic and enhancing survival pathways in experimental diabetic rats
Authors: Huang Yao-Te , Yao Chun-Hsu , Way Chia-Li , Lee Kung-Wei , Tsai Cheng-Yen , Ou Hsiu-Chung , Kuo Wei-Wen
Published: November 2012

Cardiovascular disease is one of the major causes of mortality in diabetic patients. Mounting studies have shown that garlic exhibits, possibly through its antioxidant potential, diverse biological activities. In this study, we investigated the alleviating effects of garlic oil (GO) and its two major components, diallyl disulfide (DADS) and diallyl trisulfide (DATS), on diabetic cardiomyopathy in rats. Physiological cardiac parameters were obtained using echocardiography. Apoptotic cells were evaluated using TUNEL and DAPI staining. Protein expression levels were determined using Western blotting analysis. Our findings indicated that in diabetic rat hearts significantly decreased fractional shortening percentage, increased levels of nitrotyrosine, an elevated number of TUNEL-positive cells, enhanced levels of caspase 3 expression, and decreased PI3K-Akt signaling pathway activities were observed. Furthermore, all of these alterations were reversed following both GO and DATS (or DADS) administrations through increasing PI3K-Akt signaling pathway activities and inhibiting both the death receptor-dependent and the mitochondria-dependent apoptotic pathways. In conclusion, this study shows that DATS and DADS, with the efficacy order DATS > DADS, have the therapeutic potential for ameliorating diabetic cardiomyopathy. Furthermore, the therapeutic effects of GO on diabetic cardiomyopathy should be mainly from DATS and DADS.
Perspective-taking in blindness: electrophysiological evidence of altered action representations
Authors: Imbiriba Luís Aureliano , Russo Maitê Mello , de Oliveira Laura Alice Santos , Fontana Ana Paula , Rodrigues Erika de Carvalho , Garcia Marco Antonio Cavalcanti , Vargas Claudia D.
Published: November 2012

It is well established that the mental simulation of actions involves visual and/or somatomotor representations of those imagined actions. To investigate whether the total absence of vision affects the brain activity associated with the retrieval of motor representations, we recorded the readiness potential (RP), a marker of motor preparation preceding the execution, as well as the motor imagery of the right middle-finger extension in the first-person (1P; imagining oneself performing the movement) and in the third-person (3P; imagining the experimenter performing the movement) modes in 19 sighted and 10 congenitally blind subjects. Our main result was found for the single RP slope values at the Cz channel (likely corresponding to the supplementary motor area). No difference in RP slope was found between 1P and 3P in the sighted group, suggesting that similar motor preparation networks are recruited to simulate our own and other people's actions in spite of explicit instructions to perform the task in 1P or 3P. Conversely, reduced RP slopes in 3P compared with 1P found in the blind group indicated that they might have used an alternative, nonmotor strategy to perform the task in 3P. Moreover, movement imagery ability, assessed both by means of mental chronometry and a modified version of the Movement Imagery Questionnaire-Revised, indicated that blind and sighted individuals had similar motor imagery performance. Taken together, these results suggest that complete visual loss early in life modifies the brain networks that associate with others' action representations.
Histaminergic modulation of nonspecific plasticity of the auditory system and differential gating
Authors: Ji Weiqing , Suga Nobuo
Published: November 2012

In the auditory system of the big brown bat ( Eptesicus fuscus), paired conditioned tonal (CS) and unconditioned leg stimuli (US) for auditory fear conditioning elicit tone-specific plasticity represented by best-frequency (BF) shifts that are augmented by acetylcholine, whereas unpaired CS and US for pseudoconditioning elicit a small BF shift and prominent nonspecific plasticity at the same time. The latter represents the nonspecific augmentations of auditory responses accompanied by the broadening of frequency tuning and decrease in threshold. It is unknown which neuromodulators are important in evoking the nonspecific plasticity. We found that histamine (HA) and an HA3 receptor (HA3R) agonist (α-methyl-HA) decreased, but an HA3R antagonist (thioperamide) increased, cortical auditory responses; that the HA3R agonist applied to the primary auditory cortex before pseudoconditioning abolished the nonspecific augmentation in the cortex without affecting the small cortical BF shift; and that antagonists of acetylcholine, norepinephrine, dopamine, and serotonin receptors did not abolish the nonspecific augmentation elicited by pseudoconditioning. The histaminergic system plays an important role in eliciting the arousal and defensive behavior, possibly through nonspecific augmentation. Thus HA modulates the nonspecific augmentation, whereas acetylcholine amplifies the BF shifts. These two neuromodulators may mediate differential gating of cortical plasticity.
Transcallosal inhibition in patients with callosal infarction
Authors: Li Jie-Yuan , Lai Ping-Hong , Chen Robert
Published: November 2012

Recent studies in normal subjects suggested that callosal motor fibers pass through the posterior body of the corpus callosum (CC), but this has not been tested in patients with callosal infarction. The objective of this study is to define the pathways involved in transcallosal inhibition by examining patients with infarctions in different subregions of the CC. We hypothesized that patients with lesions in the posterior one-half of the CC would have greater reduction in transcallosal inhibition between the motor cortices. Twenty-six patients with callosal infarction and 14 healthy subjects were studied. The callosal lesions were localized on sagittal MRI and were attributed to one of five segments of the CC. Transcranial magnetic stimulation was used to assess ipsilateral silent period (iSP) and short- and long-latency interhemispheric inhibition (SIHI and LIHI, respectively) originating from both motor cortices. The results showed that the iSP areas and durations were markedly reduced bilaterally in patients with callosal infarction compared with normal subjects. Patients with callosal infarctions also had less IHI bidirectionally compared with normal subjects. iSP areas and durations were lower in patients with lesions than in patients without lesions in segment 3 (posterior midbody) of the CC. Lesion burden in the posterior one-half of the CC negatively correlated transcallosal inhibition measured with iSP and SIHI. Our study suggests that callosal infarction led to reduced transcallosal inhibition, as measured by iSP, SIHI, and LIHI. Fibers mediating transcallosal inhibition cross the CC mainly in the posterior one-half.
Stability and Hopf Bifurcation in a Modified Holling‐Tanner Predator‐Prey System with Multiple Delays
Authors: Zhang Zizhen , Yang Huizhong , Liu Juan
Published: November 2012

A modified Holling‐Tanner predator‐prey system with multiple delays is investigated. By analyzing the associated characteristic equation, the local stability and the existence of periodic solutions via Hopf bifurcation with respect to both delays are established. Direction and stability of the periodic solutions are obtained by using normal form and center manifold theory. Finally, numerical simulations are carried out to substantiate the analytical results.
An Improved Line Search Filter Method for the System of Nonlinear Equations
Authors: Jin Zhong , Wang Yuqing
Published: November 2012

An improved line search filter algorithm for the system of nonlinear equations is presented. We divide the equations into two groups, one contains the equations that are treated as equality constraints and the square of other equations is regarded as objective function. Two groups of equations are updated at every iteration in the works by Nie (2004, 2006, and 2006), by Nie et al. (2008), and by Gu (2011), while we just update them at the iterations when it is needed indeed. As a consequence, the scale of the calculation is decreased in a certain degree. Under some suitable conditions the global convergence can be induced. In the end, numerical experiments show that the method in this paper is effective.
Designing Opioids That Deter Abuse
Authors: Raffa Robert B. , Pergolizzi Joseph V. , Muñiz Edmundo , Taylor Robert , Pergolizzi Jason
Published: November 2012

Prescription opioid formulations designed to resist or deter abuse are an important step in reducing opioid abuse. In creating these new formulations, the paradigm of drug development target should be introduced. Biological targets relating to the nature of addiction may pose insurmountable hurdles based on our current knowledge and technology, but products that use behavioral targets seem logical and feasible. The population of opioid abusers is large and diverse so behavioral targets are more challenging than they appear at first glance. Furthermore, we need to find ways to correlate behavioral observations of drug liking to actual use and abuse patterns. This may involve revisiting some pharmacodynamic concepts in light of drug effect rather than peak concentration. In this paper we present several new opioid analgesic agents designed to resist or deter abuse using physical barriers, the inclusion of an opioid agonist or antagonist, an aversive agent, and a prodrug formulation. Further, this paper also provides insight into the challenges facing drug discovery in this field. Designing and screening for opioids intended to resist or deter abuse is an important step to meet the public health challenge of burgeoning prescription opioid abuse.
New LMI‐Based Conditions on Neural Networks of Neutral Type with Discrete Interval Delays and General Activation Functions
Authors: Liu Guoquan , Zhou Shumin , Huang He
Published: November 2012

The stability analysis of global asymptotic stability of neural networks of neutral type with both discrete interval delays and general activation functions is discussed. New delay‐dependent conditions are obtained by using more general Lyapunov‐Krasovskii functionals. Meanwhile, these conditions are expressed in terms of a linear matrix inequality (LMI) and can be verified using the MATLAB LMI toolbox. Numerical examples are used to illustrate the effectiveness of the proposed approach.
Flexibility Training and Functional Ability in Older Adults: A Systematic Review
Authors: Stathokostas Liza , Little Robert M. D. , Vandervoort A. A. , Paterson Donald H.
Published: November 2012

Background. As indicated in a recent systematic review relating to Canada’s Physical Activity Guidelines for Older Adults, exercise interventions in older adults can maintain or improve functional abilities. Less is known about the role of flexibility in the maintenance or improvement of functional abilities, and there currently does not exist a synthesis of the literature supporting a consensus on flexibility training prescription.Purpose. To systematically review the effects of flexibility-specific training interventions on measures of functional outcomes in healthy older adults over the age of 65 years.Methods. Five electronic databases were searched for intervention studies involving concepts related to aging, flexibility, functional outcomes, and training interventions. After evaluating the articles for relevance, 22 studies were considered.Results. The results suggested that while flexibility-specific interventions may have effects on range of motion (ROM) outcomes, there is conflicting information regarding both the relationship between flexibility interventions and functional outcomes or daily functioning.Conclusions. Due to the wide range of intervention protocols, body parts studied, and functional measurements, conclusive recommendations regarding flexibility training for older adults or the validity of flexibility training interventions as supplements to other forms of exercise, or as significant positive influences on functional ability, require further investigation.
Conditions of Perfect Imaging in Negative Refraction Materials with Gain
Authors: Liang Haowen , Shao Yifeng , Zhou Jianying , Malomed Boris A. , Kurizki Gershon
Published: November 2012

Light propagation is analyzed in a negative refraction material (NRM) with gain achieved by pumping. An inherent spatial “walk-off” between the directions of phase propagation and energy transfer is known to exist in lossy NRMs. Here, the analysis is extended to the case where the NRM acts as an active material under various pumping conditions. It is shown that the condition for perfect imaging is only possible for specific wavelengths under special excitation conditions. Under excessive gain, the optical imaging can no longer be perfect.
Protein-Loosing Entropathy Induced by Unique Combination of CMV and HP in an Immunocompetent Patient
Authors: Chen S. , Lalazar G. , Barak O. , Adar T. , Doviner V. , Mizrahi M.
Published: November 2012

Protein-losing gastroenteropathies are characterized by an excessive loss of serum proteins into the gastrointestinal tract, resulting in hypoproteinemia (detected as hypoalbuminemia), edema, and, in some cases, pleural and pericardial effusions. Protein-losing gastroenteropathies can be caused by a diverse group of disorders and should be suspected in a patient with hypoproteinemia in whom other causes, such as malnutrition, proteinuria, and impaired liver protein synthesis, have been excluded. In this paper, we present a case of protein-losing enteropathy in a 22-year-old immunocompetent male with a coinfection of CMV and Hp.
Compliance of Healthcare Professionals with Safety Measures for Control of Hepatitis Viruses in Hemodialysis Centers: An Experience from Southeast Iran
Authors: Darvish Moghaddam Sodaif , Zahedi Mohammad Javad , Dalili Mahdieh , Shokoohi Mostafa
Published: November 2012

Introduction. Noncompliance with the recommended infection control measures by the healthcare professionals (HCPs) plays a major role in transmission of hepatitis B (HBV) and hepatitis C (HCV) viruses in hemodialysis (HD) wards. This study aimed to determine the compliance rate of the HCP with safety measures in the HD wards in southeast Iran. Patients and Methods. A total of 208 patients were enrolled. Adherence of HCPs with standard infection control measures was assessed. Results. Sixty-one HCPs with a mean age of 32.4 ± 11.2 years old were responsible for healthcare services. Compliance with the following items was weak: not sharing medications trolley (29.8%), disinfecting the shared instruments (46.2%), using single use materials for many patients (52.4%), carrying used materials in disposable containers (51.9%), not returning of unused materials to the clean room (55.3%), and adherence to hand washing (58.7%). Periodic monitoring for HBV and HCV was performed on 100% and 69.7% of the patients, respectively. Less than 2/3 of HCPs participated in the retraining courses. Conclusion. Compliance of HCPs with safety measures for viral hepatitis prevention was partly inadequate in HD wards. Emphasis on retraining of HCPs and official supervision would be effective steps in the reduction of viral dissemination.
Opinions about Teaching Modalities: A Comparison between Faculty and Students
Authors: Shah Shilpa , Meisenberg Gerhard
Published: November 2012

Little is known about the acceptance of different teaching/learning modalities by students and faculty in the preclinical semesters of medical school. We report the results of an anonymous survey at Ross University School of Medicine, where most of the currently popular instructional methods are used. Study subjects included 327 students and 30 faculty members. 5 questions each were asked about lectures, handouts, textbooks, mediasite (video-recorded lectures), simulation, PBL (problem based learning), TBL (team-based learning), and ICM (introduction to clinical medicine, physical examination) practicals, scored on a 5-step Likert scale. Response rates were approximately 80% for students and more than 50% for faculty. Students gave the highest scores to mediasite followed by simulation, handouts, and ICM practicals. Lowest student scores were for PBL followed by TBL and textbooks. Faculty gave highest scores for lectures, followed by ICM practicals and textbooks. They gave the lowest scores for TBL followed by mediasite and PBL. Differences between students and faculty were statistically significant for lectures (P<.001), mediasite (P=.001), textbooks (P=.002), and PBL (P=.043).
Epistemic Uncertainty Analysis: An Approach Using Expert Judgment and Evidential Credibility
Authors: Hester Patrick
Published: November 2012

When dealing with complex systems, all decision making occurs under some level of uncertainty. This is due to the physical attributes of the system being analyzed, the environment in which the system operates, and the individuals which operate the system. Techniques for decision making that rely on traditional probability theory have been extensively pursued to incorporate these inherent aleatory uncertainties. However, complex problems also typically include epistemic uncertainties that result from lack of knowledge. These problems are fundamentally different and cannot be addressed in the same fashion. In these instances, decision makers typically use subject matter expert judgment to assist in the analysis of uncertainty. The difficulty with expert analysis, however, is in assessing the accuracy of the expert's input. The credibility of different information can vary widely depending on the expert’s familiarity with the subject matter and their intentional (i.e., a preference for one alternative over another) and unintentional biases (heuristics, anchoring, etc.). This paper proposes the metric of evidential credibility to deal with this issue. The proposed approach is ultimately demonstrated on an example problem concerned with the estimation of aircraft maintenance times for the Turkish Air Force.
Impulsive Control for the Synchronization of Chaotic Systems with Time Delay
Authors: Han Ming , Liu Yang , Lu Jianquan
Published: November 2012

This paper considers impulsive control for the synchronization of chaotic systems with time delays. Based on the Lyapunov functions and the Razumikhin technique, some new synchronization criteria with an exponential convergence rate are derived. Our results show that impulses do contribute to globally exponential synchronization of dynamical systems. Besides, the impulsive moments are independent of the upper bound of time delays. Furthermore, a bigger upper bound of impulsive intervals for the synchronization of chaotic systems can be obtained when compared with many previous studies. Hence, our results are less conservative and more effective for the synchronization analysis. A numerical example is given to show the validity and potential of the developed results.
Strong Convergence Theorems for Asymptotically Weak G‐Pseudo‐Ψ‐Contractive Non‐Self‐Mappings with the Generalized Projection in Banach Spaces
Authors: Wang Yuanheng
Published: November 2012

A new concept of the asymptotically weak G‐pseudo‐Ψ‐contractive non‐self‐mapping T : G ↦ B is introduced and some strong convergence theorems for the mapping are proved by using the generalized projection method combined with the modified successive approximation method or with the modified Mann iterative sequence method in a uniformly and smooth Banach space. The proof methods are also different from some past common methods.
DNA Mismatch Repair System: Repercussions in Cellular Homeostasis and Relationship with Aging
Authors: Conde-Pérezprina Juan Cristóbal , León-Galván Miguel Ángel , Konigsberg Mina
Published: November 2012

The mechanisms that concern DNA repair have been studied in the last years due to their consequences in cellular homeostasis. The diverse and damaging stimuli that affect DNA integrity, such as changes in the genetic sequence and modifications in gene expression, can disrupt the steady state of the cell and have serious repercussions to pathways that regulate apoptosis, senescence, and cancer. These altered pathways not only modify cellular and organism longevity, but quality of life (“health-span”). The DNA mismatch repair system (MMR) is highly conserved between species; its role is paramount in the preservation of DNA integrity, placing it as a necessary focal point in the study of pathways that prolong lifespan, aging, and disease. Here, we review different insights concerning the malfunction or absence of the DNA-MMR and its impact on cellular homeostasis. In particular, we will focus on DNA-MMR mechanisms regulated by known repair proteins MSH2, MSH6, PMS2, and MHL1, among others.
Quantification of Lung Damage in an Elastase-Induced Mouse Model of Emphysema
Authors: Muñoz-Barrutia Arrate , Ceresa Mario , Artaechevarria Xabier , Montuenga Luis M. , Ortiz-de-Solorzano Carlos
Published: November 2012

Objective. To define the sensitivity of microcomputed tomography- (micro-CT-) derived descriptors for the quantification of lung damage caused by elastase instillation.Materials and Methods. The lungs of 30 elastase treated and 30 control A/J mice were analyzed 1, 6, 12, and 24 hours and 7 and 17 days after elastase instillation using (i) breath-hold-gated micro-CT, (ii) pulmonary function tests (PFTs), (iii) RT-PCR for RNA cytokine expression, and (iv) histomorphometry. For the latter, an automatic, parallel software toolset was implemented that computes the airspace enlargement descriptors: mean linear intercept(Lm)and weighted means of airspace diameters (D0,D1, andD2). A Support Vector Classifier was trained and tested based on three nonhistological descriptors usingD2as ground truth.Results.D2detected statistically significant differences(P<0.01)between the groups at all time points. Furthermore,D2at 1 hour (24 hours) was significantly lower(P<0.01)thanD2at 24 hours (7 days). The classifier trained on the micro-CT-derived descriptors achieves an area under the curve (AUC) of 0.95 well above the others (PFTS AUC = 0.71; cytokine AUC = 0.88).Conclusion. Micro-CT-derived descriptors are more sensitive than the other methods compared, to detectin vivoearly signs of the disease.
Computational Modeling of Microabscess Formation
Authors: Pigozzo Alexandre Bittencourt , Macedo Gilson Costa , Weber dos Santos Rodrigo , Lobosco Marcelo
Published: November 2012

Bacterial infections can be of two types: acute or chronic. The chronic bacterial infections are characterized by being a large bacterial infection and/or an infection where the bacteria grows rapidly. In these cases, the immune response is not capable of completely eliminating the infection which may lead to the formation of a pattern known as microabscess (or abscess). The microabscess is characterized by an area comprising fluids, bacteria, immune cells (mainly neutrophils), and many types of dead cells. This distinct pattern of formation can only be numerically reproduced and studied by models that capture the spatiotemporal dynamics of the human immune system (HIS). In this context, our work aims to develop and implement an initial computational model to study the process of microabscess formation during a bacterial infection.
The Tracial Class Property for Crossed Products by Finite Group Actions
Authors: Yang Xinbing , Fang Xiaochun
Published: November 2012

We define the concept of tracial 𝒞‐algebra of C*‐algebras, which generalize the concept of local 𝒞‐algebra of C*‐algebras given by H. Osaka and N. C. Phillips. Let 𝒞 be any class of separable unital C*‐algebras. Let A be an infinite dimensional simple unital tracial 𝒞‐algebra with the (SP)‐property, and let α : G → Aut(A) be an action of a finite group G on A which has the tracial Rokhlin property. Then A  ×α  G is a simple unital tracial 𝒞‐algebra.
Promoting Early Presentation of Breast Cancer in Older Women: Implementing an Evidence-Based Intervention in Routine Clinical Practice
Authors: Forbes Lindsay J. L. , Forster Alice S. , Dodd Rachael H. , Tucker Lorraine , Laming Rachel , Sellars Sarah , Patnick Julietta , Ramirez Amanda J.
Published: November 2012

Background. Women over 70 with breast cancer have poorer one-year survival and present at a more advanced stage than younger women. Promoting early symptomatic presentation in older women may reduce stage cost effectively and is unlikely to lead to overdiagnosis. After examining efficacy in a randomised controlled trial, we piloted a brief health professional-delivered intervention to equip women to present promptly with breast symptoms, as an integral part of the final invited mammogram at age~70, in the English National Health Service Breast Screening Programme.Methods. We trained mammographers, who then offered the intervention to older women in four breast screening services. We examined breast cancer awareness at baseline and one month in women receiving the intervention, and also in a service where the intervention was not offered.Results. We trained 27 mammographers to deliver the intervention confidently to a high standard. Breast cancer awareness increased 7-fold at one month in women receiving the intervention compared with 2-fold in the comparison service (odds ratio 15.2, 95% confidence interval 10.0 to 23.2).Conclusions. The PEP Intervention can be implemented in routine clinical practice with a potency similar to that achieved in a randomised controlled trial. It has the potential to reduce delay in diagnosis for breast cancer in older women.
A Quantum Sensor for Neutrino Mass Measurements
Authors: Cornejo Juan Manuel , Rodríguez Daniel
Published: November 2012

There are few experiments aiming at determining directly the mass of the electron antineutrino with a sensitivity of 0.2 eV by analyzing the end of theβ-decay spectrum of specific nuclei. This sensitivity can be only reached if the uncertainties arising from systematic effects are very small and very well determined. The same holds for experiments aiming at improving the sensitivity in the determination of the mass of the electron neutrino using electron-capture (ϵ)-decaying nuclei. One important input in these cases is an accurateQ-value of the decay which can be unambiguously determined from the difference of the mass of the mother and the daughter nuclei by means of Penning traps. In order to reach the required sensitivity, a novel device calledQuantum Sensoris under construction at the University of Granada (Spain). The device will allow measuring atomic masses, and thereforeQ-values from decays with unprecedented accuracy and sensitivity, using fluorescence photons from a laser-cooled ion instead of electronic detection. This paper will give an overview onQ-value measurements performed with Penning traps, relevant for neutrino mass spectrometry, describing the Quantum Sensor and the facility under construction. It will end by presenting the status of the project.