bluuebunny/crossref_metadata_2025 huggingface dataset:
c-mycAmplifications in primary breast carcinomas and their local recurrences
Authors: Aulmann S , Adler N , Rom J , Helmchen B , Schirmacher P , Sinn H P
Published: February 2006

Objective:To evaluate the role of c-myconcogene amplifications in the progression of invasive breast carcinomas.

Methods:c-mycgene copy number was evaluated in a series of 49 primary breast carcinomas and the corresponding local recurrences using fluorescence in situ hybridisation.

Results:11 of the primary carcinomas (22%) harboured c-mycamplifications; these tumours typically were hormone receptor negative and occurred in younger patients (43v53 years). At the time of relapse, six additional tumours had acquired a c-mycamplification. The mean recurrence-free survival was 24 months; c-mycamplified tumours relapsed significantly earlier than carcinomas without amplification (18v27 months). Univariate analysis showed a worse overall survival in these patients.

Conclusions:While c-mycamplifications can be observed in early stage breast cancer, especially in younger patients, they often occur later in tumour development and appear to be associated with disease progression.
The value of cytokeratin immunohistochemistry in the evaluation of axillary sentinel lymph nodes in patients with lobular breast carcinoma
Authors: Cserni G , Bianchi S , Vezzosi V , Peterse H , Sapino A , Arisio R , Reiner-Concin A , Regitnig P , Bellocq J-P , Marin C , Bori R , Penuela J M , Córdoba Iturriagagoitia A
Published: February 2006

Background:Cytokeratin immunohistochemistry (IHC) reveals a higher rate of occult lymph node metastases among lobular carcinomas than among ductal breast cancers. IHC is widely used but is seldom recommended for the evaluation of sentinel lymph nodes in breast cancer patients.

Objective:To assess the value of cytokeratin IHC for the detection of metastases in sentinel lymph nodes of patients with invasive lobular carcinoma.

Methods:The value of IHC, the types of metastasis found by this method, and the involvement of non-sentinel lymph nodes were analysed in a multi-institutional cohort of 449 patients with lobular breast carcinoma, staged by sentinel lymph node biopsy and routine assessment of the sentinel lymph nodes by IHC when multilevel haematoxylin and eosin staining revealed no metastasis.

Results:189 patients (42%) had some type of sentinel node involvement, the frequency of this increasing with increasing tumour size. IHC was needed for identification of 65 of these cases: 17 of 19 isolated tumour cells, 40 of 64 micrometastases, and 8 of 106 larger metastases were detected by this means. Non-sentinel-node involvement was noted in 66 of 161 cases undergoing axillary dissection. Although isolated tumour cells were not associated with further lymph node involvement, sentinel node positivity detected by IHC was associated with further nodal metastases in 12 of 50 cases (0.24), a proportion that is higher than previously reported for breast cancer in general.

Conclusions:IHC is recommended for the evaluation of sentinel nodes from patients with lobular breast carcinoma, as the micrometastases or larger metastases demonstrated by this method are often associated with a further metastatic nodal load.
Overexpression of cyclo-oxygenase-2 is an independent predictor of unfavourable outcome in node-negative breast cancer, but is not associated with protein kinase B (Akt) and mitogen-activated protein kinase (ERK1/2, p38) activation or with Her-2/neu signalling pathways
Authors: Schmitz K J , Callies R , Wohlschlaeger J , Kimmig R , Otterbach F , Bohr J , Lee H-S , Takeda A , Schmid K W , Baba H A
Published: February 2006

Background and aim:The production of prostaglandins is regulated by cyclo-oxygenases (COXs), which also have a role in tumour development and progression in various malignancies, including breast cancer. The mechanisms by which COX-2 contributes to unfavourable prognosis are still poorly understood. The association between expression of COX-2 and possible linked signalling pathways—namely, Akt, extracellular regulated kinases (ERK1/2), the stress-activated kinase p38 or Her-2/neu—is assessed in a series of 113 node-negative breast cancers.

Results:COX-2 was identified as an independent prognostic factor (p = 0.034) in node-negative breast cancer by survival analysis. The lack of a relationship between COX-2 expression and activated Akt, Erk1/2, p38 and Her-2/neu was indicated by statistical analysis.

Conclusions:The prognostic effect of COX-2 expression on lymph node-negative breast cancer is confirmed—COX-2 is probably not regulated by HER-2, Akt, Erk1/2 or p38. Further studies are necessary for the elucidation of the signalling pathways responsible for the modification of COX-2 expression and the increased aggressiveness of breast cancers overexpressing COX-2.
Effort/reward imbalance and sedentary lifestyle: an observational study in a large occupational cohort
Authors: Kouvonen A , Kivimäki M , Elovainio M , Pentti J , Linna A , Virtanen M , Vahtera J
Published: February 2006

Objectives:To investigate the association between effort/reward imbalance (ERI) at work and sedentary lifestyle.

Methods:Cross sectional data from the ongoing Finnish Public Sector Study related to 30 433 women and 7718 men aged 17–64 were used (n = 35 918 after exclusion of participants with missing values in covariates). From the responses to a questionnaire, an aggregated mean score for ERI in a work unit was assigned to each participant. The outcome was sedentary lifestyle defined as <2.00 metabolic equivalent task (MET) hours/day. Logistic regression with generalised estimating equations was used as an analysis method to include both individual and work unit level predictors in the models. Adjustments were made for age, marital status, occupational status, job contract, smoking, and heavy drinking.

Results:Twenty five per cent of women and 27% of men had a sedentary lifestyle. High individual level ERI was associated with a higher likelihood of sedentary lifestyle both among women (odds ratio (OR) = 1.08, 95% CI 1.01 to 1.16) and men (OR = 1.17, 95% CI 1.02 to 1.33). These associations were not explained by relevant confounders and they were also independent of work unit level job strain measured as a ratio of job demands and control.

Conclusions:A mismatch between high occupational effort spent and low reward received in turn seems to be associated with an increased risk of sedentary lifestyle, although this association is relatively weak.
Healthcare use before and after a workplace injury in British Columbia, Canada
Authors: Brown J A , McDonough P , Mustard C A , Shannon H S
Published: February 2006

Objectives:There is growing evidence that occupational injuries influence workers’ emotional and physical wellbeing, extending healthcare use beyond what is covered by the Workers’ Compensation Board (WCB).

Methods:The authors used an administrative database that links individual publicly funded healthcare and WCB data for the population of British Columbia (BC), Canada. They examined change in service use, relative to one year before the injury, for workers who required time off for their injuries (lost time = LT) and compared them to other injured workers (no lost time = NLT) and individuals in the population who were not injured (non-injured = NI).

Results:LT workers increased physician visits (22%), hospital days (50%), and mental healthcare use (43% physician visits; and 70% hospital days) five years after the injury, relative to the year before the injury, at a higher rate than the NI group. For the NLT workers, the level of increased use following the injury was between that of these two groups. These patterns persisted when adjusting for registration in the BC Medical Service Plan (MSP) and several workplace characteristics.

Conclusions:Although the WCB system is the primary mechanism for processing claims and providing information about workplace injury, it is clear that the consequences of workplace injury extend beyond what is covered by the WCB into the publicly funded healthcare system.
Characteristics of work related asthma: results from a population based survey
Authors: Breton C V , Zhang Z , Hunt P R , Pechter E , Davis L
Published: February 2006

Objectives:Many risk factors for asthma have been investigated, one of which is the workplace. Work related asthma is a frequently reported occupational respiratory disease yet the characteristics which distinguish it from non-work related asthma are not well understood. The purpose of this study was to examine differences between work related and non-work related asthma with respect to healthcare use and asthma control characteristics.

Methods:Data from the Massachusetts Behavioral Risk Factor Surveillance System for 2001 and 2002 were used for this analysis. Work related status of asthma was determined by self-report of ever having been told by a physician that asthma was work related. Healthcare measures evaluated were emergency room visits and physician visits for worsening asthma and for routine care. Characteristics of asthma control evaluated were frequency of asthma symptoms, asthma attacks, difficulty sleeping, and asthma medication usage in the last 30 days and limited activity in the past 12 months.

Results:The prevalence of lifetime and current asthma in Massachusetts were 13.0% and 9.2%, respectively. Approximately 6.0% (95% CI 4.8 to 7.3) of lifetime and 6.2% (95% CI 4.7 to 7.8) of current asthma cases were work related. In the past 12 months, individuals with work related current asthma were 4.8 times (95% CI 2.0 to 11.6) as likely to report having an asthma attack, 4.8 times (95% CI 1.8 to 13.1) as likely to visit the emergency room at least once, and 2.5 times (95% CI 1.1 to 6.0) as likely to visit the doctor at least once for worsening asthma compared to individuals with non-work related asthma.

Conclusions:Work related asthma is associated with increased frequency of asthma attacks and use of healthcare services. A better understanding of factors that contribute to differences in healthcare use and asthma control is needed to improve prevention and control strategies for individuals suffering from the disease.
Cancer mortality in German carbon black workers 1976–98
Authors: Wellmann J , Weiland S K , Neiteler G , Klein G , Straif K
Published: February 2006

Background:Few studies have investigated cancer risks in carbon black workers and the findings were inconclusive.

Methods:The current study explores the mortality of a cohort of 1535 male German blue-collar workers employed at a carbon black manufacturing plant for at least one year between 1960 and 1998. Vital status and causes of death were assessed for the period 1976–98. Occupational histories and information on smoking were abstracted from company records. Standardised mortality ratios (SMR) and Poisson regression models were calculated.

Results:The SMRs for all cause mortality (observed deaths (obs) 332, SMR 120, 95% CI 108 to 134), and mortality from lung cancer (obs 50, SMR 218, 95% CI 161 to 287) were increased using national rates as reference. Comparisons to regional rates from the federal state gave SMRs of 120 (95% CI 107 to 133) and 183 (95% CI 136 to 241), respectively. However, there was no apparent dose response relationship between lung cancer mortality and several indicators of occupational exposure, including years of employment and carbon black exposure.

Conclusions:The mortality from lung cancer among German carbon black workers was increased. The high lung cancer SMR can not fully be explained by selection, smoking, or other occupational risk factors, but the results also provide little evidence for an effect of carbon black exposure.
COUPLING PARAMETER IN SYNCHRONIZATION OF SMALL-WORLD NEURAL NETWORKS
Authors: WANG SHENG-JUN , XU XIN-JIAN , WU ZHI-XI , WANG YING-HAI
Published: February 2006

We investigate the critical features of coupling parameters in the synchronization of the ensemble of identical neural networks with small-world connectivity. An exponential decay form is observed in the extreme case of global coupling among subsystems and full connection in each networks: there exists a maximum and a minimum of the critical coupling intensity for synchronization in this spatially extended system. For partial coupling, we present the primary result about the critical coupling fraction for various linked degree of subnetworks.
LOCALIZED STRUCTURES IN NONEQUILIBRIUM SYSTEMS
Authors: DESCALZI ORAZIO , GUTIÉRREZ PABLO , TIRAPEGUI ENRIQUE
Published: February 2006

We study numerically a prototype equation which arises generically as an envelope equation for a weakly inverted bifurcation associated to traveling waves: The complex quintic Ginzburg–Landau equation. We show six different stable localized structures including stationary pulses, moving pulses, stationary holes and moving holes, starting from localized initial conditions with periodic and Neumann boundary conditions.
DIVERGENT EVOLUTION PATHS OF DIFFERENT GENETIC FAMILIES IN THE PENNA MODEL
Authors: SITARZ MIKOŁAJ , MAKSYMOWICZ ANDRZEJ
Published: February 2006

We present some simulations results of population growth and evolution, using the standard asexual Penna model, with individuals characterized by a string of bits representing a genome containing some possible mutations. After about 20 000 simulation steps, when only a few genetic families are still present from among rich variety of families at the beginning of the simulation game, strong peaks in mutation distribution functions are observed. This known effect is due to evolution rules with hereditary mechanism. The birth and death balance in the simulation game also leads to elimination of families specified by different genomes. The number of families G(t) versus time t follow the power law, G∝tn. Our results show the power coefficient exponent n is changing with time. Starting from about -1, smoothly achieves about -2 after hundreds of steps, and finally has semi-smooth transition to 0, when only one family exists in the environment. This is in contrast with constant n about -1 as found, for example, in Ref. 1. We suspect that this discrepancy may be due to two different time scales in simulations — initial stages follow the n ≈ -1 law, yet for large number of simulation steps we get n ≈ -2, provided the random initial population was sufficiently big to allow for still reliable statistical analysis. The n ≈ -1 evolution stage seems to be associated with the Verhulst mechanism of population elimination due to the limited environmental capacity — when the standard evolution rules were modified, we observed a plateau (n =0) in the power law in short time scale, again followed by n ≈ -2 law for longer times. The modified model uses birth rate controlled by the current population instead of the standard Verhulst death factor.
NUMERICAL SIMULATION OF ISOTHERMAL MICRO FLOWS BY LATTICE BOLTZMANN METHOD AND THEORETICAL ANALYSIS OF THE DIFFUSE SCATTERING BOUNDARY CONDITION
Authors: NIU X. D. , SHU C. , CHEW Y. T.
Published: February 2006

A Lattice Boltzmann model for simulating micro flows has been proposed by us recently (Europhysics Letters, 67(4), 600–606 (2004)). In this paper, we will present a further theoretical and numerical validation of the model. In this regards, a theoretical analysis of the diffuse-scattering boundary condition for a simple flow is carried out and the result is consistent with the conventional slip velocity boundary condition. Numerical validation is highlighted by simulating the two-dimensional isothermal pressure-driven micro-channel flows and the thin-film gas bearing lubrication problems, and comparing the simulation results with available experimental data and analytical predictions.
PROPERTIES OF ITERATIVE MONTE CARLO SINGLE HISTOGRAM REWEIGHTING
Authors: GMITRA MARTIN , HORVÁTH DENIS
Published: February 2006

We present an iterative Monte Carlo algorithm for which the temperature variable is attracted by a critical point. The algorithm combines techniques of single histogram reweighting and linear filtering. The ferromagnetic 2D Ising model is studied numerically as an illustration. In that case, the iterations reach a stationary regime with an invariant probability distribution function of temperature which peaked near the pseudocritical temperature of the specific heat. The sequence of generated temperatures is analyzed in terms of stochastic autoregressive model. The error of histogram reweighting can be better understood within the suggested model. The presented model yields a simple relation, connecting the variance of pseudocritical temperature and the parameter of linear filtering.
FIELD-INDUCED INTERACTION OF A PSEUDOSCALAR PARTICLE WITH PHOTON IN A MAGNETIZED e-e+ PLASMA
Authors: MIKHEEV N. V. , NARYNSKAYA E. N.
Published: February 2006

The effective interaction of a pseudoscalar particle with photon in plasma with the presence of a constant uniform magnetic field is investigated. It is shown that under some physical conditions, the effective coupling between pseudoscalar particle and photon does not depend on medium parameters and particles momentum. The probability of the familon decays into photon pair in a strongly magnetized degenerate ultrarelativistic plasma is calculated.
INFLATIONARY SOLUTIONS WITH A FIVE-DIMENSIONAL COMPLEX SCALAR FIELD
Authors: VAN DER BIJ J. J. , RADU EUGEN
Published: February 2006

We discuss inflationary solutions of the coupled Einstein–Klein–Gordon equations for a complex field in a five-dimensional spacetime with a compact x5 dimension. As a new feature, the scalar field contains a dependence on the extra dimension of the form exp (imx5), corresponding to Kaluza–Klein excited modes. In a four-dimensional picture, a nonzero m implies the presence of a new term in the scalar field potential. An interesting feature of these solutions is the possible existence of several periods of oscillation of the scalar field around the equilibrium value at the minimum of the potential. These oscillations lead to cosmological periods of accelerated expansion of the universe.
A BRIEF HISTORY OF THE DISCOVERY OF THE SU(3) MASS FORMULA AND OTHER SUBJECTS
Authors: OKUBO SUSUMU
Published: February 2006

We give a brief history of the discovery of the SU(3) mass formula and offer a few remarks on the inequality of partial decay rates of particles and their antiparticles.
SOME LOWER BOUNDS ON GEOMETRIC SEPARABILITY PROBLEMS
Authors: ARKIN ESTHER M. , HURTADO FERRAN , MITCHELL JOSEPH S. B. , SEARA CARLOS , SKIENA STEVEN S.
Published: February 2006

We obtain lower bounds in the algebraic computation tree model for deciding the separability of two disjoint point sets. In particular, we show Ω(n log n) time lower bounds for separability by means of strips, wedges, wedges with apices on a given line, fixed-slopes double wedges, and triangles, which match the complexity of the existing algorithms, and therefore prove their optimality.
INTERVAL-BASED TRACING OF STRANGE ATTRACTORS
Authors: MICHELUCCI DOMINIQUE , FOUFOU SEBTI
Published: February 2006

The method described here relies on interval arithmetic and graph theory to compute guaranteed coverings of strange attractors like Hénon attractor. It copes with infinite intervals, using either a geometric method or a new directed projective interval arithmetic.
MINIMUM AREA CONVEX PACKING OF TWO CONVEX POLYGONS
Authors: TANG KAI , WANG CHARLIE C. L. , CHEN DANNY Z.
Published: February 2006

Given two convex polygons P and Q in the plane that are free to translate and rotate, a convex packing of them is the convex hull of a placement of P and a placement of Q whose interiors do not intersect. A minimum area convex packing of P and Q is one whose area is minimized. The problem of designing a deterministic algorithm for finding a minimum area convex packing of two convex polygons has remained open. We address this problem by first studying the contact configurations between P and Q and their algebraic structures. Crucial geometric and algebraic properties on the area function are then derived and analyzed which enable us to successfully discretize the search space. This discretization, together with a delicate algorithmic design and careful complexity analysis, allows us to develop an efficient O((n + m)nm) time deterministic algorithm for finding a true minimum area convex packing of P and Q, where n and m are the numbers of vertices of P and Q, respectively.
EXPLORING THE EFFECTIVENESS OF LOW CONTINUOUS CHEMO-BIO-THERAPEUTIC TREATMENT OF CANCER THROUGH ANALYTICAL SYSTEM MODELLING
Authors: MUKHERJEE ABHIK , MAJUMDER DURJOY , ICBAL ASIF
Published: February 2006

Analytical models of tumor growth in the presence and absence of drug is important for studying the dynamics of treatment in oncology. In this paper, a time-variant state-space model is investigated. The model captures the inherent nonlinearity of the system. Physiological constraints of the system are considered in the model and controllability of the tumor load is examined. If it is possible to find a sequence of drug doses that can drive the tumor load to any arbitrary negligibly small final condition from any arbitrary initial condition in a given number of days without affecting the physiological state of the patient, the tumor is said to be controllable. Drug administration strategies like maximum tolerated dose, metronomic chemotherapy in the presence and absence of immunotherapy have been examined. It is found that low yet prolonged continuous dosing of drug along with tuning of biological factors may be a better workable strategy for positive treatment outcome.
EPISTEMOLOGY OF COMPUTATIONAL BIOLOGY: MATHEMATICAL MODELS AND EXPERIMENTAL PREDICTION AS THE BASIS OF THEIR VALIDITY
Authors: DOUGHERTY EDWARD R. , BRAGA-NETO ULISSES
Published: February 2006

Knowing the roles of mathematics and computation in experimental science is important for computational biology because these roles determine to a great extent how research in this field should be pursued and how it should relate to biology in general. The present paper examines the epistemology of computational biology from the perspective of modern science, the underlying principle of which is that a scientific theory must have two parts: (1) a structural model, which is a mathematical construct that aims to represent a selected portion of physical reality and (2) a well-defined procedure for relating consequences of the model to quantifiable observations. We also explore the contingency and creative nature of a scientific theory. Among the questions considered are: Can computational biology form the theoretical core of biology? What is the basis, if any, for choosing one particular model over another? And what is the role of computation in science, and in biology in particular? We examine how this broad epistemological framework applies to important statistical methodologies pertaining to computational biology, such as expression-based phenotype classification, gene regulatory networks, and clustering. We consider classification in detail, as the epistemological issues raised by classification are related to all computational-biology topics in which statistical prediction plays a key role. We pay particular attention to classifier-model validity and its relation to estimation rules.
GENERALIZATIONS OF THE ENERGY-FLUX PARABOLIC EQUATION
Authors: MIKHIN DMITRY
Published: February 2006

Parabolic equations written in terms of energy flux are inherently immune to the problem of energy conservation at vertical interfaces. Mikhin [J. Comp. Acoust. 9 (2001) 183–203] achieved exact reciprocity and energy conservation in a finite-difference PE model following this approach. However, his model used the implicit Crank–Nicolson scheme in range that requires a small range step for accurate solution. The present paper generalizes the exponential propagator of Collins [J. Acoust. Soc. Am. 93 (1993) 1736–1742] to solve the energy-flux PE. The obtained solution remains strictly reciprocal and energy conserving, while allowing large range steps. The numerical efficiency is improved by one or two orders of magnitude. A technique is proposed to calculate the acoustic pressure within the large steps, so the solution combines fast advance in range with dense range sampling. Numerical examples are provided.
A FINITE ELEMENT METHOD FOR THE PARABOLIC EQUATION IN AEROACOUSTICS COUPLED WITH A NONLOCAL BOUNDARY CONDITION FOR AN INHOMOGENEOUS ATMOSPHERE
Authors: KAMPANIS NIKOLAOS A.
Published: February 2006

The standard parabolic equation is used to simulate the far-field, low-frequency sound propagation over ground with mild range-varying topography. The atmosphere has a lower layer with a general, variable index of refraction. An unbounded upper layer with a squared refractive index varying linearly with height is considered and modeled by the nonlocal boundary condition of Dawson, Brooke and Thomson.1 A finite element/transformation of coordinates method is used to transform the initial-boundary value problem to one with a rectangular computational domain and then discretize it. The solution is marched in range by the Crank–Nicolson scheme. A discrete form of the nonlocal boundary condition, which is left unaffected by the transformation of coordinates, is employed in the finite element method. The fidelity of the overall method is shown in the numerical simulations performed for various cases of sound propagation in an inhomogeneous atmosphere over a ground with irregular topography.
ANALYSIS OF STRUCTURES WITH STOCHASTIC INTERFACES IN THE MEDIUM-FREQUENCY RANGE
Authors: BLANZÉ CLAUDE , ROUCH PHILIPPE
Published: February 2006

This paper proposes efficient techniques to obtain effective quantities when dealing with complex structures (including stochastic parameters, such as interface parameters) in medium-frequency vibrations. The first ingredient is the use of a dedicated approach — the Variational Theory of Complex Rays (VTCR) — to solve the medium-frequency problem. The VTCR, which uses two-scale shape functions verifying the dynamic equation and the constitutive relation, can be viewed as a means of expressing the power balance at the different interfaces between substructures. The second ingredient is the use of the Polynomial Chaos Expansion (PCE) to calculate the random response. Since the only uncertain parameters are those which appear in the interface equations (which, in this application, are the complex connection stiffness parameters), this approach leads to very low computation costs.
HIGH-ORDER CURVILINEAR SIMULATIONS OF FLOWS AROUND NON-CARTESIAN BODIES
Authors: MARSDEN OLIVIER , BOGEY CHRISTOPHE , BAILLY CHRISTOPHE
Published: February 2006

The current work describes the application of high-order numerical techniques to single or multiple overset curvilinear body-fitted grids, demonstrating the feasibility of direct computations of noise radiated by flows around complex non-Cartesian bodies. Flows of both physical and industrial interest can be investigated with this approach. We first rapidly describe the numerical techniques implemented in our curvilinear simulations. The explicit high-order differencing and filtering schemes are presented, as well as their application to the curvilinear Navier–Stokes equations. We then present brief results of various 2-D acoustic simulations. First the flow around a cylinder, and the associated acoustic field, are described. The diameter-based Reynolds number Re D = 150 is under the critical Reynolds number of the onset of 3-D phenomena in the vortex-shedding. Simulation results can thus be meaningfully compared to experimental measurements. A case of acoustic scattering is then examined. A non-compact monopolar source is placed half way between two differently sized cylinders. A complex diffraction pattern is created, and resulting RMS pressure data are compared to the analytical solution. Finally the noise generated by a low Reynolds number laminar flow around a NACA 0012 airfoil is presented.
A DISCUSSION ON THE ENERGY-CONSERVING PROPERTY OF A THREE-DIMENSIONAL WAVE EQUATION
Authors: CHEN CHI-FANG , LEE DING , HSIEH LI-WEN , WANG CHUNG-WU
Published: February 2006

A three-dimensional wave equation has been introduced by Lee–Schultz–Saad (LSS equation). This equation has been discretized into a difference equation. A stable numerical solution has been introduced to solve this difference equation. A computer model, FOR3D, implements this numerical solution. The FOR3D has been used for various applications in the acoustic community. It is important and of great interest to find out whether or not the LSS equation is energy-conserving. This paper will discuss fully the energy-conserving property of the LSS equation.
AN EMPIRICAL ANALYSIS OF NOISE IN PULSED TERAHERTZ SYSTEMS
Authors: HANDLEY J. W. , COHEN NETTA , BOYLE R. D. , BERRY ELIZABETH
Published: February 2006

Terahertz pulsed imaging systems use broadband pulses of sub-millimetre wavelength radiation for spectroscopy and imaging. This Letter demonstrates that a four parameter stable distribution models the observed noise of the pulses, with two of the parameters dependent on material type and thickness. We additionally show that this noise is not characterised by either Gaussian or Gaussian-mixture models.
EXPERIMENTAL SIGNATURE OF REGISTRATION NOISE IN PULSED TERAHERTZ SYSTEMS
Authors: COHEN NETTA , HANDLEY J. W. , BOYLE R. D. , BRAUNSTEIN SAMUEL L. , BERRY ELIZABETH
Published: February 2006

This Letter reports results from time domain measurements in a terahertz pulsed imaging system and suggests that a mechanical resetting mechanism in the pump-probe delay stage results in a small but resolvable noise signal. In the setup described here, this effect dominates all other sources of noise such as the background Johnson noise or shot noise, and can hence be isolated and analysed in detail. An analysis of the noise signal is used to estimate the physical limitations of the pump-probe system being employed. A comparison of the results with an analytic prediction allows us to formulate a useful and general signature of registration noise, that should make it easy to detect in any sufficiently narrowband signal.
SOUTH AFRICA'S RESERVE: CHALLENGES AND RECOMMENDATIONS FOR IMPLEMENTING SUSTAINABLE DEVELOPMENT POLICIES
Authors: QUA-ENOO ALISON BODURTHA , SCHENDEL KATE , QUINN NEVIL
Published: February 2006

South Africa introduced a visionary policy for water resource management in 1998. The South African National Water Act (Act 36 of 1998) contains several innovative mechanisms with the potential to transform water resource management within the country and abroad. The Reserve is one of these innovations, guaranteeing a basic water requirement for both human needs and ecosystem health. This article discusses the process of Reserve determination and implementation in South Africa and identifies challenges and opportunities for successful implementation. Based on the perceptions of 28 water managers, consultants, and researchers, the key issues and recommendations for improving implementation are presented. The major findings indicate that political support, the capacity of the implementing organization, supporting policies, strong linkages between policy actors and effective monitoring programs are key issues in the successful implementation of sustainable development policy mechanisms.
MANAGING SUSTAINABILITY WITHIN CONSTRUCTION PROJECTS
Authors: KHALFAN MALIK M. A.
Published: February 2006

This paper presents a 'Sustainability Management Activity Zone' (SMAZ) to support the implementation of sustainable construction practices integrated within a generic design and construction process map, the Process Protocol (1998). This is being investigated within the C-SanD Project (Creating, Sustaining, and Disseminating Knowledge for Sustainable Construction: Tools, Methods and Architectures). A brief overview of sustainable development and sustainable construction is presented, followed by an introduction to the C-SanD project and its initial findings related to current practice and the perception of sustainability within the construction industry based on the first round of interviews. The paper also discusses some of the sustainability issues identified during the field work, and highlights the need for a structured framework to consider and incorporate sustainability issues during the whole design and construction process of a project. The latter part of the paper discusses the incorporation of these issues within the Process Protocol, as SMAZ. The paper argues that the key for successful use of SMAZ within the industry is the awareness about the sustainable development among design and construction staff and operatives, knowing the importance of different activities and sub-activities within the SMAZ tool, and motivation to bring changes for betterment within the current day-to-day construction and design processes. The paper towards the end also highlights the areas which need further research and development.
CAPACITY BUILDING FOR EIA IN BRAZIL: PRELIMINARY CONSIDERATIONS AND PROBLEMS TO BE OVERCOME
Authors: KIRCHHOFF DENIS
Published: February 2006

In Brazil, Environmental Impact Assessment (EIA) has been part of the environmental legislation since 1981 when the Brazilian National Environmental Policy (BNEP) was established. The BNEP established several tools intended to reconcile socio-economic development with environment conservation. More than twenty years have passed, and what is still seen in general is a need for improved capacity to implement these instruments to their full extent, particularly because of the lack of integration among these tools and, in many instances, a lack of the necessary levels of power and resources to enforce the very instruments that are aimed at integrating environmental concerns into decision-making. A brief background about the EIA process in Brazil is introduced, as well as regional examples of Capacity Building (CB) initiatives undertaken. Finally, a systemic approach to build EIA capacity is presented. The main conclusion is that CB is needed to effectively implement EIA components in Brazil and a systemic approach might offer improved outcomes to achieve desired levels of EIA capacity.
FUZZY DYNAMIC LOGIC
Authors: PERLOVSKY LEONID I.
Published: February 2006

Fuzzy logic is extended toward dynamic adaptation of the degree of fuzziness. The motivation is to explain the process of learning as a joint model improvement and fuzziness reduction. A learning system with fuzzy models is introduced. Initially, the system is in a highly fuzzy state of uncertain knowledge, and it dynamically evolves into a low-fuzzy state of certain knowledge. We present an image recognition example of patterns below clutter. The paper discusses relationships to formal logic, fuzzy logic, complexity and draws tentative connections to Aristotelian theory of forms and working of the mind.
A SCENARIO ELICITATION METHOD WITH MULTI-DIMENSIONAL HEARING AND HIERARCHICAL INTEGRATION PROCESS
Authors: KUSHIRO NORIYUKI , OHSAWA YUKIO
Published: February 2006

The effective scenario elicitation method has been developed by combining the process of chance discovery with the method of requirements engineering. The proposed method consists of the multi-dimensional hearing and the hierarchical integration process. The capability of the method to elicit a useful scenario was confirmed by theoretical analysis with a visualization tool named KeyGraph and by an experiment of eliciting scenario by using a prototype of an operation panel for electric appliances controller used in a home.
ON THE PROPERTIES OF A GENERALIZED CLASS OF T-NORMS IN INTERVAL-VALUED FUZZY LOGICS
Authors: VAN GASSE BART , CORNELIS CHRIS , DESCHRIJVER GLAD , KERRE ETIENNE E.
Published: February 2006

Since it does not generate any MTL-algebra (prelinear residuated lattice), the lattice [Formula: see text] of closed subintervals of [0, 1] falls outside the mainstream of research on formal fuzzy logics. However, due to the intimate connection between logical connectives on [Formula: see text] and those on [0, 1], many relevant logical properties can still be maintained, sometimes in a slightly weaker form. In this paper, we focus on a broad class of parametrized t-norms on [Formula: see text]. We derive their corresponding residual implicators, and examine commonly imposed logical properties. Importantly, we formally establish one-to-one correspondences between ∨-definability (respectively, weak divisibility) for t-norms of this class and strong ∨-definability (resp., divisibility) for their counterparts on [0, 1].
FUZZY FILTERS ON THE RESIDUATED LATTICES
Authors: ZHANG JIA-LU , ZHOU HONG-JUN
Published: February 2006

In this paper, the lattice operations and the adjoint pair on the fuzzy filters set on residuated lattices are defined, the conclusion that the fuzzy filters lattice defined as such is a distributive residuated lattice is obtained. An order-reversing involution on the fuzzy strong-prime filters sublattice is introduced. It is proved that the fuzzy strong-prime filters sublattice is a quasi-Boolean algebra.
Mechanisms of Liver Injury. III. Role of glutathione redox status in liver injury
Authors: Han Derick , Hanawa Naoko , Saberi Behnam , Kaplowitz Neil
Published: February 2006

GSH is the most abundant redox molecule in cells and thus the most important determinant of cellular redox status. Thiols in proteins can undergo a wide range of reversible redox modifications (e.g., S-glutathionylation, S-nitrosylation, and disulfide formation) during times of increased exposure to reactive oxygen and nitrogen species, which can affect protein activity. These reversible thiol modifications regulated by GSH may be nanoswitches to turn on and off proteins, similar to phosphorylation, in cells. In the cytoplasm, an altered redox state can activate (e.g., MAPKs and NF-E2-related factor-2) and inhibit (e.g., phosphatases and caspases) proteins, whereas in the nucleus, redox alterations can inhibit DNA binding of transcription factors (e.g., NF-κB and activator protein-1). The consequences include the promotion of expression of antioxidant genes and alterations of hepatocyte survival as well as the balance between necrotic versus apoptotic cell death. Therefore, the understanding of the redox regulation of proteins may have important clinical ramifications in understanding the pathogenesis of liver diseases.
Effect of meal and propranolol on whole body and splanchnic oxygen consumption in patients with cirrhosis
Authors: Krag Aleksander , Simonsen Lene , Henriksen Jens H. , Ottesen Lone , Bendtsen Flemming
Published: February 2006

Our aim was to measure whole body energy expenditure after a mixed liquid meal, with and without simultaneous propranolol infusion, in patients with cirrhosis. We also wanted to investigate the effect of propranolol on substrate fluxes and oxygen uptake in the tissues drained by the hepatic vein and azygos vein in the postprandial period in these patients. Whole-body oxygen uptake, hepatic blood flow, hepatic venous pressure gradient and net-hepatic fluxes of oxygen, lactate, glucose, glycerol, and free fatty acids (FFA) were measured in 12 patients with alcoholic cirrhosis before and for 2 h after ingestion of a mixed liquid meal (700 kcal). Half of the patients ( n = 6) were randomized to a treatment group receiving intravenous infusion of propranolol in combination with the meal. The meal-induced energy expenditure was significantly lower in patients given propranolol [15.0 ± 18.9 vs. 67.0 ± 26.1 kJ/120 min (means ± SD), P < 0.01]. Meal-induced whole body oxygen uptake was lower in patients receiving propranolol (19.2 ± 38 vs. 135.7 ± 61 mmol/120 min, P < 0.01), and the meal-induced increase in splanchnic oxygen uptake was nonexistent when propranolol was administered in combination (−13.2 ± 34.8 vs. 110.4 ± 34.8 mmol/120 min, P = 0.04). Postprandially, the propranolol group had a tendency toward a reduced splanchnic glucose output, and the FFA uptake was significantly reduced. Propranolol reduces meal-induced whole body oxygen uptake and energy expenditure as well as splanchnic oxygen uptake. The splanchnic reduction in oxygen consumption can explain almost the entire reduction in whole body oxygen consumption.
Short-term electroacupuncture at Zusanli resets the arterial baroreflex neural arc toward lower sympathetic nerve activity
Authors: Michikami Daisaku , Kamiya Atsunori , Kawada Toru , Inagaki Masashi , Shishido Toshiaki , Yamamoto Kenta , Ariumi Hideto , Iwase Satoshi , Sugenoya Junichi , Sunagawa Kenji , Sugimachi Masaru
Published: February 2006

Although electroacupuncture reduces sympathetic nerve activity (SNA) and arterial pressure (AP), the effects of electroacupuncture on the arterial baroreflex remain to be systematically analyzed. We investigated the effects of electroacupuncture of Zusanli on the arterial baroreflex using an equilibrium diagram comprised of neural and peripheral arcs. In anesthetized, vagotomized, and aortic-denervated rabbits, we isolated carotid sinuses and changed intra-carotid sinus pressure (CSP) from 40 to 160 mmHg in increments of 20 mmHg/min while recording cardiac SNA and AP. Electroacupuncture of Zusanli was applied with a pulse duration of 5 ms and a frequency of 1 Hz. An electric current 10 times the minimal threshold current required for visible muscle twitches was used and was determined to be 4.8 ± 0.3 mA. Electroacupuncture for 8 min decreased SNA and AP ( n = 6). It shifted the neural arc (i.e., CSP-SNA relationship) to lower SNA but did not affect the peripheral arc (i.e., SNA-AP relationship) ( n = 8). SNA and AP at the closed-loop operating point, determined by the intersection of the neural and peripheral arcs, decreased from 100 ± 4 to 80 ± 9 arbitrary units and from 108 ± 9 to 99 ± 8 mmHg (each P < 0.005), respectively. Peroneal denervation eliminated the shift of neural arc by electroacupuncture ( n = 6). Decreasing the pulse duration to <2.5 ms eliminated the effects of SNA and AP reduction. In conclusion, short-term electroacupuncture resets the neural arc to lower SNA, which moves the operating point toward lower AP and SNA under baroreflex closed-loop conditions.
Mechanisms of unpinning and termination of ventricular tachycardia
Authors: Ripplinger Crystal M. , Krinsky Valentin I. , Nikolski Vladimir P. , Efimov Igor R.
Published: February 2006

High-energy defibrillation shock is the only therapy for ventricular tachyarrhythmias. However, because of adverse side effects, lowering defibrillation energy is desirable. We investigated mechanisms of unpinning, destabilization, and termination of ventricular tachycardia (VT) by low-energy shocks in isolated rabbit right ventricular preparations ( n = 22). Stable VT was initiated with burst pacing and was optically mapped. Monophasic “unpinning” shocks (10 ms) of different strengths were applied at various phases throughout the reentry cycle. In 8 of 22 preparations, antitachycardia pacing (ATP: 8–20 pulses, 50–105% of period, 0.8–10 mA) was also applied. Termination of reentry by ATP was achieved in only 5 of 8 preparations. Termination by unpinning occurred in all 22 preparations. Rayleigh's test showed a statistically significant unpinning phase window, during which reentry could be unpinned and subsequently terminated with E80 (magnitude at which 80% of reentries were unpinned) = 1.2 V/cm. All reentries were unpinned with field strengths ≤2.4 V/cm. Unpinning was achieved by inducing virtual electrode polarization and secondary sources of excitation at the core of reentry. Optical mapping revealed the mechanisms of phase-dependent unpinning of reentry. These results suggest that a 20-fold reduction in energy could be achieved compared with conventional high-energy defibrillation and that the unpinning method may be more effective than ATP for terminating stable, pinned reentry in this experimental model.
Persistent pain model reveals sex difference in morphine potency
Authors: Wang Xiaoya , Traub Richard J. , Murphy Anne Z.
Published: February 2006

Central or systemic administration of agonists directed at the μ or δ opiate receptors generally produce a greater degree of analgesia in males than in females. To date, most studies examining sex-based differences in opioid analgesia have used acute noxious stimuli (i.e., tail-flick and hot plate test); thus the potential dimorphic response of centrally acting opiates in the alleviation of persistent inflammatory pain is not well established. In the present study, right hind paw withdrawal latency (PWL) to radiant thermal stimuli was measured in intact male and cycling female Sprague-Dawley rats before and after unilateral hind paw injection of the inflammatory agent complete Freund's adjuvant (CFA). Control animals received intraplantar injection of saline. Twenty four hours after CFA or saline injection, animals received either saline or morphine bisulfate (0.5–15 mg/kg sc). Separate groups of control or inflamed animals were tested on their responsiveness to morphine at 7, 14, and 21 days post-CFA or saline. No sex differences were noted for baseline PWLs, and females displayed slightly less thermal hyperalgesia at 24 h post-CFA. At all morphine doses administered, both the antihyperalgesic effects of morphine in the inflamed animals and the antinociceptive effects of morphine in control animals were significantly greater in males compared with females. Similarly, in males, the antihyperalgesic effects of morphine increased significantly at 7–21 days post-CFA; no significant shift in morphine potency was noted for females. These studies demonstrate sex-based differences in the effects of morphine on thermal hyperalgesia in a model of persistent inflammatory pain.
Early gestation dexamethasone alters baroreflex and vascular responses in newborn lambs before hypertension
Authors: Segar Jeffrey L. , Roghair Robert D. , Segar Emily M. , Bailey Melissa C. , Scholz Thomas D. , Lamb Fred S.
Published: February 2006

Exposure of the early gestation ovine fetus to exogenous glucocorticoids induces alterations in postnatal cardiovascular physiology, including hypertension. To determine whether autonomic function and systemic vascular reactivity are altered by in utero programming before the development of systemic hypertension, we examined arterial baroreflex function and in vivo hemodynamic and in vitro vascular responses to vasoactive agents in 10- to 14-day-old newborn lambs exposed to early gestation glucocorticoids. Dexamethasone (Dex, 0.28 mg·kg−1·day−1) or saline was administered to pregnant ewes by intravenous infusion over 48 h beginning at 27 days gestation (term 145 days), and lambs were allowed to deliver ( n = 6 in each group). Resting mean arterial blood pressure (MABP; 77 ± 1 vs. 74 ± 3 mmHg) and heart rate (HR; 249 ± 9 vs. 226 ± 21 beats/min) were similar in Dex-exposed and control animals, respectively. The arterial baroreflex curve, relating changes in HR to MABP, was significantly shifted toward higher pressure in the Dex-exposed lambs although no change in the sensitivity (gain) of the response was seen. In vivo changes in blood pressure in response to bolus doses of ANG II (20, 50, and 100 ng/kg) and phenylephrine (2, 5, and 10 μg/kg) were similar in the two groups. However, Dex lambs displayed greater decreases in MABP in response to ganglionic blockade with tetraethylammonium bromide (10 mg/kg; −30 ± 3 vs. −20 ± 3 mmHg, P < 0.05) and greater increases in MABP after nitric oxide synthase blockade with NG-nitro-l-arginine (25 mg/kg; 23 ± 3 vs. 13 ± 2 mmHg, P < 0.05) compared with control lambs. By in vitro wire myography, mesenteric and femoral artery microvessel contractile responses to KCl were similar, whereas responses to endothelin (in mesenteric) and norepinephrine (in femoral) were significantly attenuated in Dex lambs compared with controls. Femoral vasodilatory responses to forskolin and sodium nitroprusside were similar in the two groups ( n = 4). These findings suggest that resetting of the baroreflex, accompanied by increased sympathetic activity and altered nitric oxide-mediated compensatory vasodilatory function, may be important contributors to programming of hypertension.