bluuebunny/crossref_metadata_2025 huggingface dataset:
Landscape scale, heterogeneity, and the viability of Serengeti grazers
Authors: Fryxell John M. , Wilmshurst John F. , Sinclair Anthony R. E. , Haydon Daniel T. , Holt Robert D. , Abrams Peter A.
Published: February 2005

Species persistence can be threatened by substantial temporal variation in food resources over time. On the other hand, spatial heterogeneity in resources at the landscape scale might allow mobile consumers to compensate for temporal variability in resource availability at the local scale. We evaluated this hypothesis, using an extensive data set on foraging, grass growth, and movement by Thomson's gazelles living on the Serengeti Plains. Here we show that modelled populations of Thomson's gazelles can only persist under Serengeti conditions in the face of observed levels of rainfall stochasticity by making adaptive movements to take advantage of ephemeral spatial distributions of food resources. More importantly, our models suggest that Thomson's gazelles in Serengeti require unrestricted access to relatively large areas of grassland (> 1600 km2) to guarantee long‐term persistence, particularly when there is positive spatial autocorrelation in resource abundance, as is the case in Serengeti. If this proves to be true for other species and/or other systems, then understanding of complex behavioural responses to spatially and temporally heterogeneous food supplies may be essential to successful conservation of grazing herbivores.
Dialogue: a theoretical framework for distance education instructional systems
Authors: Gorsky Paul , Caspi Avner
Published: February 2005

This paper presents a theoretical framework for viewing elements that comprise distance education instructional systems in terms of dialogue. It is assumed that learning is mediated by intrapersonal dialogue and facilitated by interpersonal dialogue. Every resource in a distance education instructional system (eg, instructor availability, asynchronous communication networks, self‐instruction texts, etc) is analysed in terms of the dialogue mode it supports. The framework offers three advantages: (1) a unified, simple, and coherent description of the mechanisms at play in distance education systems, (2) clear‐cut operational definitions, and (3) hypotheses that may be investigated empirically.
Goal Setting Through Contradiction Analysis in the Bionics‐Oriented Construction Process
Authors: Hill Bernd
Published: February 2005

The goal setting of technical development tasks and the uncovering of contradictions at the level of invention form the conditions for problem‐solving. By including bionics in the construction process, the technical designer and/or product developer receives a rich arsenal of efficient biological structures as a suggestion for the problem solving. The way in which living nature can be used to help in the search for solutions is demonstrated using the example of the thermal insulation of house fronts.
Nonsurgical Management of Cardiac Tamponade Caused by a Temporary Pacemaker Lead
Authors: TREHAN VIJAY , MEHTA VIMAL , MUKHOPADHYAY SAIBAL , YUSUF JAMAL , RASTOGI VISHAL , YADUVANSHI AMITABH , TYAGI SANJAY
Published: February 2005

Right ventricular perforation secondary to temporary pacemaker lead, resulting in cardiac tamponade, is a rare but life‐threatening complication. Surgery is usually the definitive management described for such cases. We describe successful sealing of such a perforation by percutaneous instillation of cyanoacrylate glue, through a guiding catheter in the pericardial sac at the perforation site.
Moderate Exercise Induces Different Autonomic Modulations of Sinus and AV Node
Authors: SCHUCHERT ANDREAS , WAGNER STEFAN M. , FROST GABY , MEINERTZ THOMAS
Published: February 2005

Background: The routine determination of heart rate variability (HRV) from surface ECGs is based on RR intervals because of the difficulty to precisely locate the P‐wave fiducial point on surface ECG recordings. The aim of the study was to assess the changes of RR, PP, and PR intervals at rest and during moderate exercise. The time intervals were determined from atrial and ventricular pacemaker‐mediated intracardiac electrograms.

Methods: Ten patients in sinus rhythm with intrinsic AV node conduction who had received the dual‐chamber pacemaker Logos (Biotronik) were included. High‐resolution atrial and ventricular intracardiac electrograms were transmitted at rest in supine position and during walking to a portable external recorder. Recording sequences of 150 successive heart cycles were used for HRV analyses after computer‐assisted triggering of P and R events. The HRV‐index SDNN and power spectral densities for the low (LF; 0.04–0.15 Hz) as well as high (HF; 0.15–0.40 Hz) frequency bands were determined.

Results: SDNN decreased from 26.0 ± 8.1 ms at rest to 18.3 ± 4.2 ms during exercise for the PP intervals (P < 0.05) and from 26.8 ± 8.1 to 18.4 ± 4.1 ms for the RR intervals (P < 0.05). The LF/HF ratio increased from 2.02 ± 1.3 to 4.5 ± 1.5 in the atrium (P < 0.05) and from 2.0 ± 1.2 to 5.2 ± 1.9 in the ventricle P < 0.05). Comparing atrial and ventricular HRV at both activity levels, no significant differences were observed for the power of LF and HF spectral components. Regarding the PR intervals SDNN, the total power and the LF/HF ratio did not significantly change during exercise.

Conclusions: The described technique enabled to record intracardiac electrograms not only at rest, but also during moderate exercise and to use them for HRV evaluation. The changes of PP and RR, but not of the PR intervals, during exercise indicate that autonomic inputs to the sinus node and AV node are independent from each other. The ventricular HRV seems to derive mainly from variations of the sinus node pulse formation.
Pharmacokinetic/Pharmacodynamic Modelling in Oncological Drug Development
Authors: Karlsson Mats O. , Anehall Therese , Friberg Lena E. , Henningsson Anja , Kloft Charlotte , Sandström Marie , Xie Rujia
Published: February 2005

Abstract: For many oncological agents, myelosuppression is the dose‐limiting toxicity and the quantitative characterisation of the relationship between drug dose, plasma concentration and haematological toxicity is of importance in the drug development. Mechanism‐based population pharmacokinetic‐pharmacodynamic models have been developed for this purpose and the applications of these in candidate selection, first‐in‐man studies, prodrug and formulation development, dose finding, schedule optimisation, assessing influence of modifying agents, drug combination studies, subgroup identification and feedback individualisation are reviewed.
The Odds that Clinically Unrecognized Poor or Partial Adherence Confuses Population Pharmacokinetic/Pharmacodynamic Analyses
Authors: Vrijens Bernard , Gross Robert , Urquhart John
Published: February 2005

Abstract: Electronic compilation of ambulatory patients' or trial participants' dosing histories has revealed that a wide range of dosing patterns, markedly skewed toward underdosing, occur in virtually every disease and treatment situation so far studied. In planning ambulatory trials and their analyses, one should recognize that patients' variable exposure to test drugs, created by their diversely erratic execution of protocol‐specified dosing regimens, is generally the single largest source of variance in drug responses. Trial subjects' erratic dosing behaviour may, if ignored, weaken the trial's assay sensitivity. In contrast, reliably compiled and soundly analyzed dosing histories may greatly inform the analysis of the trial. Dosing histories found to be associated with suboptimal clinical results can highlight particular dosing patterns that should be avoided. Thus begins the sequence leading from first observations, to repeat observations, to ethically possible experimental designs, to causal inference, i.e., learning and then confirming. With the broadening use of electronic monitoring to estimate longitudinal drug exposure, the need exists for an explicit discipline that concerns itself with `what the patient does with the drug'. It is called Pharmionics.
Predicting the Outcome of Phase III Trials using Phase II Data: A Case Study of Clinical Trial Simulation in Late Stage Drug Development
Authors: De Ridder Filip
Published: February 2005

Abstract: Maximizing the likelihood of success in Phase III is the ultimate goal of the use of modelling and simulation in the drug development process. The success in Phase III depends primarily on two questions: 1) Is the drug regimen actually efficacious and safe in the targeted patient population?, and 2) Will the planned Phase III clinical trial(s) be successful in demonstrating this? Traditionally, the first question is addressed in a qualitative, overall interpretation of available study results. Integrating this information into a formal statistical model of the action of the drug, allows running simulations to investigate the impact of uncertainties and imprecision in this knowledge. The second question is related to having an adequately designed clinical trial. Clinical trial simulation, using a drug action model, supplemented with appropriate models for disease progression and trial execution, allows assessing the impact of typical design features such as doses, sample size, in‐/exclusion criteria, drop‐out and trial duration on the trial outcome and thus optimising trial design. In this contribution, the use of modelling and simulation in the Phase II to Phase III transition is illustrated using real data of a drug for symptom relief in a chronic condition. A dose‐response model of the clinical response was developed using data from Phase II. Simulations were performed to 1) generate the range of possible outcomes of ongoing Phase III trials and compare these to the blinded data being generated from these trials; 2) assess the robustness of the ongoing Phase III trials with respect to uncertainty of the true dose‐response, patient variability in baseline severity and drug‐response, and 3) assess the likelihood of achieving a clinically relevant response with a dose lower than those included in the trials.
Developmental processes and the induction of cardiovascular function: conceptual aspects
Authors: Hanson Mark A. , Gluckman Peter D.
Published: February 2005

The epidemiological basis of the developmental origins of disease concept is now widely accepted. The current impetus in research concerns establishing the underlying mechanisms. We discuss the wider biological nature of the phenomenon, with particular reference to ‘maternal effects’, the processes observed in many species by which the mother can induce phenotypic effects in her offspring. Animal models permit investigation of the induction of cardiovascular phenotypic attributes which resemble pathological effects in humans. We discuss the importance of transitions in aspects of the pre‐versusthe postnatal environment, with emphasis on nutrition and energy expenditure, and the critical role which the timing of environmental cues plays in inducing effects on the offspring. Coupled with the effects of specific maternal dietary components, the effects on the offspring are argued to involve epigenetic mechanisms. In this review we provide a conceptual framework for synthesising experimental and clinical data, important for considering the impact of the developmental origins concept in a life‐course approach to the prevention of cardiovascular disease.
Developmental changes in expression of GABAA receptor‐channels in rat intrinsic cardiac ganglion neurones
Authors: Fischer Harald , Harper Alexander A. , Anderson Colin R. , Adams David J.
Published: February 2005

The effects of γ‐aminobutyric acid (GABA) on the electrophysiological properties of intracardiac neurones were investigated in the intracardiac ganglion plexus in situ and in dissociated neurones from neonatal, juvenile and adult rat hearts. Focal application of GABA evoked a depolarizing, excitatory response in both intact and dissociated intracardiac ganglion neurones. Under voltage clamp, both GABA and muscimol elicited inward currents at −60 mV in a concentration‐dependent manner. The fast, desensitizing currents were mimicked by the GABAA receptor agonists muscimol and taurine, and inhibited by the GABAA receptor antagonists, bicuculline and picrotoxin. The GABAA0 antagonist (1,2,5,6‐tetrahydropyridin‐4‐yl)methyl phosphonic acid (TPMPA), had no effect on GABA‐induced currents, suggesting that GABAA receptor‐channels mediate the response. The GABA‐evoked current amplitude recorded from dissociated neurones was age dependent whereby the peak current density measured at −100 mV was ∼20 times higher for intracardiac neurones obtained from neonatal rats (P2–5) compared with adult rats (P45–49). The decrease in GABA sensitivity occurred during the first two postnatal weeks and coincides with maturation of the sympathetic innervation of the rat heart. Immunohistochemical staining using antibodies against GABA demonstrate the presence of GABA in the intracardiac ganglion plexus of the neonatal rat heart. Taken together, these results suggest that GABA and taurine may act as modulators of neurotransmission and cardiac function in the developing mammalian intrinsic cardiac nervous system.
Reproductive barriers and hybridity in two spruces, Picea rubens and Picea mariana, sympatric in eastern North America
Authors: Major John E , Mosseler Alex , Johnsen Kurt H , Rajora Om P , Barsi Debby C , Kim K -H , Park J -M , Campbell Moira
Published: February 2005

Hybridization between red spruce (Picea rubens Sarg.) and black spruce (Picea mariana (Mill.) BSP), late- and early-successional species, respectively, has resulted in identification and management problems. We investigated the nature and magnitude of reproductive and life-cycle success barriers in controlled intra- and inter-specific crosses of red and black spruce. We quantified a number of reproductive, germination, phenological, and performance traits, and examined traits by parental pedigree and hybrid index. Species' pollen had no effect on number of aborted or nonpollinated ovules. Controlled intraspecific crosses had, on average, 6.6 times more filled seeds than interspecific crosses. Cone and seed morphometric traits were species specific, with seed traits showing negative hybridization effects on both species. Germination, cotyledon number, and seedling height had significant species-specific traits, with hybrids showing an additive or slightly negative heterosis. Severe, negative heterosis appears to be of limited importance as an isolating barrier between red and black spruce. Reproductive phenology was remarkably similar among species and hybrid progenies when grown in common garden experiments. Crossability barriers are clearly paramount in maintaining the separation of the species. Ecological separation based on ecophysiological differences (e.g., shade tolerance) also represents an important prezygotic barrier for minimizing the negative effects of hybridization (e.g., postzygotic inviability) on reproductive fitness.Key words: cone, seed and seedling traits, genetic variation, phenology, red and black spruce.
Évolution des teneurs en polyamines libres et conjuguées dans les feuilles de vigne (Vitis vinifera 'Cabernet Sauvignon') saine et atteinte d'eutypiose
Authors: Rifai Lalla Aïcha , Koussa Tayeb , Geny Laurence , Fassouane Aziz , Broquedis Michel , Dubos Bernadette
Published: February 2005

Effects of Eutypa lata, the fungal agent of eutypiosis, on polyamine (putrescine (Put), spermidine (Spd), spermine (Spm), diaminopropane (Dap)) and tyramine (Tyr) contents in grapevine leaves were studied to determine the relationship between these components and disease development. The external symptoms of eutypiosis are small and necrotic leaves, which could be observed on only one arm or on two arms of the vine stock. This study was carried out on healthy leaves (S, borne by healthy vine stock), apparently healthy leaves (Aps, borne by one arm without symptoms, whereas the other arm was diseased), and moderately (M. mal.) and strongly (F. mal.) diseased leaves. We analysed free polyamines (free PAs, chlorhydric acid soluble fraction), conjugated polyamines (PAs-fpm, PAs covalently linked to molecules with low molecular mass like hydroxycinnamic acids), and bound polyamines (PAs-mm, covalently linked to macromolecules) in Vitis vinifera L. 'Cabernet sauvignon', a variety sensitive to eutypiosis. In diseased leaves, we noted a decrease of free PAs, PAs-fpm, free Tyr, and Tyr-fpm levels. By contrast, the Dap-fpm level was increased by the disease. Eutypiosis also induced an increase of Spm-mm and Dap-mm levels, whereas the Put-mm and Spd-mm levels were decreased. Free Put, free Spd, PAs-fpm, free Tyr, and Tyr-fpm levels were higher in apparently healthy leaves than in healthy leaves. The PAs-mm levels were slightly affected by eutypiosis in apparently healthy leaves. The specific role of each type of polyamines and tyramine is discussed with regard to the host-parasite relationship.Key words: polyamines, leaf, Eutypa lata, Vitis vinifera.
Development of tensile strength in compatible and incompatible sweet cherry graftings
Authors: Pedersen Bjarne Hjelmsted
Published: February 2005

The tensile strengths of graftings between three selected sweet cherry cultivars and five selected cherry rootstocks were determined with an Instron instrument 6, 12, and 18 weeks after grafting and compared with the tensile strength of self-grafted rootstocks and graftings of rootstocks used as scions. The combination of sweet cherry cultivars and rootstocks was selected to provide a range of compatibility based on preliminary work. The tensile strengths of sweet cherry cultivars grafted on different rootstocks never exceeded the tensile strengths of the self-grafted rootstocks. Rootstocks grafted as scions on Prunus avium L. rootstocks and self-grafted rootstocks produced some of the strongest unions tested and also produced union strength much faster than any of the other combinations. The degree of compatibility was quantified and results indicated that if this value was below 0.2, measured 18 weeks after grafting, it corresponded to combinations with major risks of delayed incompatibility.Key words: tensile strength, grafting, compatibility, sweet cherry, Prunus avium.
Alternative model structures for bioenergetics budgets of a cruising predatory gadoid: incorporating estimates of food conversion and costs of locomotion
Authors: Andersen Niels G , Riis-Vestergaard Jorgen
Published: February 2005

Swimming costs of North Sea saithe (pollock) (Pollachius virens) were estimated from a balanced energy budget equation using field estimates of food ration and growth together with two alternative food conversion functions. Food ration estimates were obtained by application of a gastric evacuation model to field data on amount and composition of stomach contents. Laboratory-based net conversion efficiency, κlab, produced values of 1.616.72 of the activity multiplier, whereas estimates of 1.443.27 were obtained from application of an activity-modulated net conversion efficiency, κwild. The activity multiplier ranged from 2.0 to 2.5 at optimum cruising speed. The high activity levels obtained by application of κlab probably reflect low-cost accumulation of lipid in laboratory saithe. All together, the results indicated that net conversion efficiency in North Sea saithe was better described by κwild (ranging from 0.43 to 0.50) as opposed to κlab (0.510.76). Model estimates of food ration and body growth using activity costs at optimum cruising speed further demonstrated the sensitivity of estimates from the balanced energy budget equations to applied parameter values and field estimates of variables.
The costs of habitat utilization of wild, farmed, and domesticated juvenile Atlantic salmon (Salmo salar)
Authors: Enders Eva C , Boisclair Daniel , Roy André G
Published: February 2005

We compared morphometry and total swimming costs of wild, farmed (first-generation hatchery progeny of wild progenitors) and domesticated (seventh-generation progeny of the Norwegian aquaculture strain) juvenile Atlantic salmon (Salmo salar). Respirometry experiments were performed to assess total swimming costs of fish ranging in size from 4.0 to 16.1 g wet mass at a water temperature of 15 °C. Fish were subjected to flow conditions of low and high turbulence. Total swimming costs increased significantly with intensity of turbulence and were, on average, 1.4 times higher at high than at low turbulence. Total swimming costs were 2.4- to 4.0-fold higher than predicted by forced swimming models developed under conditions that minimize flow heterogeneity. Total swimming costs of wild and farmed fish were not statistically different (average difference = 6.7%). Hence, swimming costs models developed using farmed fish may be used to estimate swimming costs of wild fish. However, domesticated fish had total swimming costs 12.0% to 29.2% higher than farmed or wild fish. This may be related to domesticated fish having deeper bodies and smaller fins.
Energy-related juvenile winter mortality in a northern population of Atlantic salmon (Salmo salar)
Authors: Finstad Anders G , Ugedal Ola , Forseth Torbjørn , Næsje Tor F
Published: February 2005

By comparing the population frequency distributions for specific somatic energy between samplings using quantilequantile (QQ) plots, we tested for energy-related mortality of juvenile (2- and 3-year-old) Atlantic salmon (Salmo salar) sampled at monthly intervals throughout three consecutive winters in a Norwegian river located at 70°N. Between several of the sampling periods, changes in the distributions of specific energy were observed corresponding to removal of low-energy individuals. By using energetic modelling we demonstrated that metabolic processes or feeding could not be responsible for the shifts in the shape of the energy distributions and that negative-energy-dependent mortality was the most likely explanation for the observations. No changes in mean size of the fish or in the shape of the size distributions were observed between successive sampling periods, indicating that mortality was linked to levels of storage energy rather than to body size per se. Our study indicated a critical body energy level for survival of juvenile salmon at approximately 44004800 J·g1, corresponding to a depletion of storage lipids.
Long-term consequences of variation in timing and manner of fry introduction on juvenile Atlantic salmon (Salmo salar) growth, survival, and life-history expression
Authors: Letcher Benjamin H , Dubreuil Todd , O'Donnell Matthew J , Obedzinski Mariska , Griswold Kitty , Nislow Keith H
Published: February 2005

We tested the influence of introduction time and the manner of introduction on growth, survival, and life-history expression of Atlantic salmon (Salmo salar). Introduction treatments included three fry stocking times and stream rearing of embryos. Despite poor growth conditions during the early stocking period, early-stocked fish were larger throughout the entire study period, likely the result of prior residence advantage. This interpretation was reinforced by the laboratory study, where early-stocked fish outgrew late-stocked fish when reared together, but not when they were reared separately. In contrast to growth, abundance of stocked fish was greatest for fish stocked during the middle period, and this stocking group produced the greatest number of smolts. Despite smaller size, survival of stream-incubated fish was generally greater than survival of stocked fish. Introduction timing had a pronounced effect on smolt age but a weak effect on extent of parr maturation. Overall, these observations indicate that small differences (~2 weeks) in introduction time can have long-term effects on size, survival, and life-history expression. Results suggest stabilizing selection on introduction times, mediated by the interaction between prior residence (advantage to fish introduced earlier) and habitat suitability (advantage to fish introduced later).
Foraging, growth, and loss rate of young-of-the-year Atlantic salmon (Salmo salar) in relation to habitat use in Catamaran Brook, New Brunswick
Authors: Girard Isabelle L , Grant James W.A , Steingrímsson Stefán Ó
Published: February 2005

The ideal despotic distribution predicts that individuals occupying preferred habitats will have higher fitness than those in less preferred habitats, whereas the ideal free distribution predicts that average fitness will be equal in all habitats. To test between these two alternatives, we studied habitat use in relation to foraging, growth, and loss rates of 216 individually tagged young-of-the-year Atlantic salmon (Salmo salar). Fish were observed by snorkelling between 2 July and 4 September 1999 in Catamaran Brook, New Brunswick. In a multiple logistic regression, the variables that best discriminated between the habitats used and not used by fish were mean flow velocity and water depth; the fish preferred habitats of intermediate flow velocity (648 cm·s1) and depth (2039 cm). Fish in preferred habitats experienced higher levels of food abundance and had higher foraging rates but did not differ in body size or growth rate compared with those in less preferred habitats, perhaps because of higher energetic costs. In addition, loss rate did not differ significantly between preferred and less preferred habitats. Our data suggest that salmonid populations at low density may be better described by an ideal free distribution rather than by an ideal despotic one.
Changes in the human muscle force-velocity relationship in response to resistance training and subsequent detraining
Authors: Andersen Lars L. , Andersen Jesper L. , Magnusson S. Peter , Suetta Charlotte , Madsen Jørgen L. , Christensen Lasse R. , Aagaard Per
Published: February 2005

Previous studies show that cessation of resistance training, commonly known as “detraining,” is associated with strength loss, decreased neural drive, and muscular atrophy. Detraining may also increase the expression of fast muscle myosin heavy chain (MHC) isoforms. The present study examined the effect of detraining subsequent to resistance training on contractile performance during slow-to-medium velocity isokinetic muscle contraction vs. performance of maximal velocity “unloaded” limb movement (i.e., no external loading of the limb). Maximal knee extensor strength was measured in an isokinetic dynamometer at 30 and 240°/s, and performance of maximal velocity limb movement was measured with a goniometer during maximal unloaded knee extension. Muscle cross-sectional area was determined with MRI. Electromyographic signals were measured in the quadriceps and hamstring muscles. Twitch contractions were evoked in the passive vastus lateralis muscle. MHC isoform composition was determined with SDS-PAGE. Isokinetic muscle strength increased 18% ( P < 0.01) and 10% ( P < 0.05) at slow and medium velocities, respectively, along with gains in muscle cross-sectional area and increased electromyogram in response to 3 mo of resistance training. After 3 mo of detraining these gains were lost, whereas in contrast maximal unloaded knee extension velocity and power increased 14% ( P < 0.05) and 44% ( P < 0.05), respectively. Additionally, faster muscle twitch contractile properties along with an increased and decreased amount of MHC type II and MHC type I isoforms, respectively, were observed. In conclusion, detraining subsequent to resistance training increases maximal unloaded movement speed and power in previously untrained subjects. A phenotypic shift toward faster muscle MHC isoforms (I → IIA → IIX) and faster electrically evoked muscle contractile properties in response to detraining may explain the present results.
Role of Insulin Resistance in Familial Combined Hyperlipidemia
Authors: Veerkamp M.J. , de Graaf J. , Stalenhoef A.F.H.
Published: February 2005

Objective—

Insulin resistance is associated with increased triglyceride levels, low high-density lipoprotein cholesterol, small dense low-density lipoprotein (LDL), and increased apolipoprotein B (apoB) levels, all characteristics of familial combined hyperlipidemia (FCH). Therefore, we explored the role of insulin resistance in FCH lipid phenotype expression.

Methods and Results—

FCH was defined by traditional diagnostic criteria including plasma total cholesterol or triglyceride levels >90th percentile. Insulin resistance was assessed by the Homeostasis Model Assessment (HOMA) index. In total, 132 subjects with FCH, 350 normolipidemic relatives, and 81 spouses who referenced as controls were studied. FCH subjects were significantly more insulin resistant compared with controls and normolipidemic relatives (HOMA index 2.9 [95% CI, 2.6 to 3.2], 2.2 [95% CI, 2.0 to 2.5], and 2.0 [95% CI, 1.9 to 2.2], respectively), even after correction for sex, age, and body mass index (BMI). The degree of insulin resistance was associated with the lipid phenotype expression, and a change in insulin-resistant state was associated with a change in lipid phenotype expression over 5 years. For any level of insulin resistance and degree of obesity, FCH subjects had increased levels of apoB and more small dense LDL compared with controls.

Conclusion—

Insulin resistance is a characteristic feature of FCH, which is not fully explained by their increased BMI and is associated with (change in) lipid phenotype expression. Furthermore, our results support the concept of genetic origin of high apoB and small dense LDL in FCH, which is modulated by insulin resistance and obesity.
Distinct NF-κB Regulation by Shear Stress Through Ras-Dependent IκBα Oscillations
Authors: Ganguli Arunima , Persson Linda , Palmer Ian R. , Evans Iona , Yang Lin , Smallwood Rod , Black Richard , Qwarnstrom Eva E.
Published: February 2005

NF-κB, a transcription factor central to inflammatory regulation during development of atherosclerosis, is activated by soluble mediators and through biomechanical inputs such as flow-mediated shear- stress. To investigate the molecular mechanisms underlying shear stress mediated signal transduction in vascular cells we have developed a system that applies flow-mediated shear stress in a controlled manner, while inserted in a confocal microscope. In combination with GFP-based methods, this allows continuous monitoring of flow induced signal transduction in live cells and in real time. Flow-mediated shear stress, induced using the system, caused a successive increase in NF-κB–regulated gene activation. Experiments assessing the mechanisms underlying the NF-κB induced activity showed time and flow rate dependent effects on the inhibitor, IκBα, involving nuclear translocation characterized by a biphasic or cyclic pattern. The effect was observed in both endothelial- and smooth muscle cells, demonstrated to impact noncomplexed IκBα, and to involve mechanisms distinct from those mediating cytokine signals. In contrast, effects on the NF-κB subunit relA were similar to those observed during cytokine stimulation. Further experiments showed the flow induced inter-compartmental transport of IκBα to be regulated through the Ras GTP-ase, demonstrating a pronounced reduction in the effects following blocking of Ras activity. These studies show that flow-mediated shear stress, regulated by the Ras GTP-ase, uses distinct mechanisms of NF-κB control at the molecular level. The oscillatory pattern, reflecting inter-compartmental translocation of IκΒα, is likely to have fundamental impact on pathway regulation and on development of shear stress-induced distinct vascular cell phenotypes.
Mechanisms of Atrial Fibrillation Termination by Pure Sodium Channel Blockade in an Ionically-Realistic Mathematical Model
Authors: Kneller* James , Kalifa* Jérôme , Zou Renqiang , Zaitsev Alexey V. , Warren Mark , Berenfeld Omer , Vigmond Edward J. , Leon L. Joshua , Nattel Stanley , Jalife José
Published: February 2005

The mechanisms by which Na
+
-channel blocking antiarrhythmic drugs terminate atrial fibrillation (AF) remain unclear. Classical “leading-circle” theory suggests that Na
+
-channel blockade should, if anything, promote re-entry. We used an ionically-based mathematical model of vagotonic AF to evaluate the effects of applying pure Na
+
-current (I
Na
) inhibition during sustained arrhythmia. Under control conditions, AF was maintained by 1 or 2 dominant spiral waves, with fibrillatory propagation at critical levels of action potential duration (APD) dispersion. I
Na
inhibition terminated AF increasingly with increasing block, terminating all AF at 65% block. During 1:1 conduction, I
Na
inhibition reduced APD (by 13% at 4 Hz and 60% block), conduction velocity (by 37%), and re-entry wavelength (by 24%). During AF, I
Na
inhibition increased the size of primary rotors and reduced re-entry rate (eg, dominant frequency decreased by 33% at 60% I
Na
inhibition) while decreasing generation of secondary wavelets by wavebreak. Three mechanisms contributed to I
Na
block–induced AF termination in the model: (1) enlargement of the center of rotation beyond the capacity of the computational substrate; (2) decreased anchoring to functional obstacles, increasing meander and extinction at boundaries; and (3) reduction in the number of secondary wavelets that could provide new primary rotors. Optical mapping in isolated sheep hearts confirmed that tetrodotoxin dose-dependently terminates AF while producing effects qualitatively like those of I
Na
inhibition in the mathematical model. We conclude that pure I
Na
inhibition terminates AF, producing activation changes consistent with previous clinical and experimental observations. These results provide insights into previously enigmatic mechanisms of class I antiarrhythmic drug-induced AF termination. The full text of this article is available online at http://circres.ahajournals.org
Derivation of Transcranial Doppler Criteria for Rescue Intra-arterial Thrombolysis
Authors: Saqqur Maher , Shuaib Ashfaq , Alexandrov Andrie V. , Hill Michael D. , Calleja Sergio , Tomsick Thomas , Broderick Joseph , Demchuk Andrew M.
Published: February 2005

Background and Purpose—

Transcranial Doppler (TCD) has the potential to identify acute stroke patients with arterial occlusion when treatment with intravenous recombinant tissue plasminogen activator (rtPA) may fail to open the vessel. We examined clinical utility and prognostic value of TCD flow findings in patients enrolled in an intravenous/intra-arterial rtPA pilot trial (Interventional Management of Stroke [IMS] study).

Methods—

Patients enrolled in the IMS trial who underwent urgent TCD performed before intra-arterial rtPA treatment were included. TCD findings were analyzed by a mean flow velocity (MFV) ratio using reciprocal middle carotid artery (MCA) depths bilaterally (affected MCA-to-contralateral MCA MFV ratio [aMCA/cMCA MFV ratio]). The clinical utility of TCD was determined by its ability to predict outcome and identify a proximal arterial occlusion that requires intra-arterial lysis per protocol.

Results—

Twenty-nine of 80 patients enrolled in IMS trial had pre–intra-arterial lysis TCD (mean age, 61±11; men-to-women ratio: 17:12; median baseline National Institutes of Health Stroke Score, 17). No temporal window was found in 3 patients (10%). Cerebral angiography was performed at mean 174±36 minutes from stroke onset. TCD was performed at median 93.5 minutes from onset. The aMCA/cMCA MFV ratio <0.6 had a sensitivity of 94% (95% confidence interval [CI], 63% to 99%), specificity of 100% (97.5%; lower CI of 54%), positive predictive value of 100% (lower CI, 80%); and negative predictive value of 86% (CI, 42% to 99%) for identifying proximal occlusion in the anterior circulation that require intra-arterial lysis. All patients with absent MCA flow (n=6) had poor outcomes (modified Rankin Scale ≥3) (
P
=0.014).

Conclusion—

TCD is a useful modality for evaluating the arterial circulation in acute ischemic stroke patients; it may have significant potential as a screening tool for intravenous/intra-arterial lysis protocols.
Journalist or Witness?
Authors: Spellman Robert L.
Published: February 2005

Jonathan Randal, who covered the Balkan Wars for The Washington Post, was subpoenaed to testify before the International Criminal Tribunal for the Former Yugoslavia. He challenged the subpoena. The Tribunal Appeals Chamber ruled that war correspondents have a qualified privilege to refuse to testify before the tribunal. The court held that it must balance the interest in free flow of information from war zones against the interest in the fair administration of justice. This article argues that the Appeals Chamber holding was deficient because it omitted the safety of the correspondent, his family and his sources from the equation. The American case of Robert Young Pelton, who interviewed John Walker Lindh in Afghanistan for Cable News Network (CNN), is also reviewed.
Defending Communicative Spaces
Authors: Sarikakis Katharine
Published: February 2005

The role of the European Parliament in the formation of media and cultural policies is a largely underresearched area, despite the implications of the institution’s active involvement in supranational decision-making regimes for emancipatory politics in Europe. Through a historical overview, this article argues that the EP has successfully defended existing communicative spaces and promoted the creation of new ones. In its efforts to defend European communications and culture from processes of cultural domination, however, it has failed to acknowledge dominations within the EU. The article positions the institution within a supranational arrangement of economic and political power and identifies the structural constraints and resistance space for public interest centred politics.
Sound from silence: On listening in organizational learning
Authors: Jacobs Claus , Coghlan David
Published: February 2005

One of the central challenges for organizational learning at an intersubjective level has been proposed in terms of developing a shared language as a prerequisite for shared understanding in a community. In this respect, social learning theory suggests communities of practice as loci, and discourse as the medium of such learning. Rather than knowledge acquisition, social learning refers to identity formation through competent participation in a discursive practice. Listening as a central, yet so far neglected, element of discursive practice involves the constitution of a relational basis that allows for intersubjective meaning generation. We suggest listening as a condition for the possibility of social learning and illustrate our suggestion with an empirical case. We discuss the implications of our argument for organizational and social learning as well as its broader relevance.
Effect of Phase Shift on Engineering Properties of [±Θ] Plain Weave Laminates
Authors: Woo Kyeongsik , Suh Young W. , Whitcomb John D.
Published: February 2005

In this study, the effective elastic properties are numerically calculated for laminated plain weave textile composites with various orientation angles. A single-field macroelement with modified subdomain integration is used in the analysis to reduce computer resource requirement while efficiently accounting for the internal microstructure. A calculation procedure based on the Monte Carlo method is employed to consider the random tow arrangement due to the shift between the layers. Results show that significant deviation from average values occur when the orientation angles are near 0 for the extensional modulus and Poisson’s ratio and 45 for the shear modulus. It is also found that the average properties calculated for the two-layer specimen have large differences as compared to the CLT results, which indicate that caution must be used when analyzing thin plain weave composite structures.
The print media’s portrayal of the private prison
Authors: Blakely Curtis R. , Bumphus Vic W.
Published: February 2005

This article draws on a study of the print media’s portrayal of prison privatization, primarily in the USA. Findings reveal that privatization is portrayed as a practice closely associated with profit, efficiency, and overcrowding. Currently, the print media focuses on privatization’s external characteristics rather than on those internal traits more closely associated with inmates, staff, and issues of operational quality. Furthermore, the print media is portraying prison privatization more negatively now than at any time since its re-emergence nearly two decades ago.
Adapting to change
Authors: Foster Pam , Foster Allan
Published: February 2005

Surveys the use of business information in UK libraries, based on two questionnaires mailed in September 2004 to libraries/information departments.
Response to risk
Authors: Kelleher Zoë , Hall Hazel
Published: February 2005

This article describes how electronic mail (email) has developed from being a simple, efficient and cost-effective means of communicating short messages across computer networks into a broad platform on which are based a wide range of applications for which email was not intended. A study is reported which considers the main sources of email security risk and the creation and deployment of email security policies. It sets out the key email security elements needing to be addressed in terms of the supporting literature, where these issues were analyzed to assess user perceptions of email security risk. Two data sets were collected during 2003, involving: interview data from discussions with six email security experts from several companies; and survey data from a single case study company where the 285 highly-educated employees were regular users of email, and were supposed to practise their handling of email with reference to the company’s email security policy. The survey results indicated strong support for the view that email security was a major concern for companies, but low opinions were held concerning end-user knowledge of email security issues in the organisations with which they had contact. A major priority in reducing email security risk was seen to be the education of end-users in appropriate email handling practices. All participants were concerned about the occurrence of viruses and spam but tended to be undecided regarding whether or not interception was a real threat and it was generally felt that the low perceived threat of interception did not justify the cost and disruption involved in the introduction of encryption software. Considerable interest was expressed regarding the question of employee and employer rights when drafting email policies and these comments reflected the level of ambiguity in the existing legislation, where none of the people interviewed was aware of any guidelines to help a company protect its interests while upholding the privacy rights of its employees.
Rethinking Scientific Specialization
Authors: Wray K. Brad
Published: February 2005

My aim in this paper is to re-examine specialization in science. I argue that we need to acknowledge the role that conceptual changes can play in the creation of new specialties. Whereas earlier sociological accounts focus on social and instrumental changes as the cause of the creation of new specialties, I argue that conceptual changes play an important role in the creation of some scientific specialties. Specifically, I argue that conceptual developments played an important role in the creation of both endocrinology and virology.
Your Attention Please! Heeding the Proverbs
Authors: Clifford Richard J.
Published: February 2005

How does an individual biblical proverb attract the interest of a reader, or, in other words, assert its authority? It often does so by skillful use of analogy, drawinga memorable parallel between one area of reality and another, for example, a king and a lion, wealth and friendship. Sayings further invite attention by their formal features (e.g. alliteration, rhyme) and by their ideas. Among arresting ideas can be listed ellipsis, paradox, irony, humor, and satire. A group of biblical proverbs are analyzed in this article to demonstrate the thesis.
Putting Elihu in his Place: A Proposal for the Relocation of Job 32–37
Authors: Clines David J.A.
Published: February 2005

The proposal is that the Elihu speeches (Job 32–37) originally preceded Job 28. The effects of this rearrangement are (1) that Yahweh speaks directly after Job has concluded his final speech (Job 29–31), (2) that the ‘poem on wisdom' (Job 28) can be identified as the conclusion of the Elihu speeches, with which it has much in common, and (3) that four difficulties in the wording of 32.1-2 can be overcome if Elihu's intervention immediately follows the speeches of the other friends. Finally, on the basis of the arrangement of columns in the Qumran Isaiah scroll (1QIsa) an explanation is offered for how the physical displacement of these chapters in a Job scroll could have occurred in antiquity.
Self-Managing Teamwork and Psychological Well-Being
Authors: van Mierlo Heleen , Rutte Christel G. , Kompier Michiel A. J. , Doorewaard Hans A. C. M.
Published: February 2005

In this article, we present a qualitative discussion of 28 empirical studies on self-managing team-work and psychological well-being. We address three questions: (a) Which variables did they include and which results did they obtain?; (b) How did authors deal with issues of level of theory, measurement, and analysis?; and (c) Do such level issues affect the results of the studies? This review demonstrates that only job satisfaction is consistently related to self-managing teamwork. In addition, authors often fail to specify the level of their theory, thereby impeding judgment on the appropriateness of analysis procedures. Finally, we present preliminary evidence that level issues may affect the results. We plead for the incorporation of multilevel theory andanalysistechniquesintothefieldofself-managingteamworkandpsychologicalwell-being.
Paradigm Lost? Reassessing Theory of International Politics
Authors: Goddard Stacie E. , Nexon Daniel H.
Published: February 2005

Constructivists attack the social theory of Kenneth Waltz’s Theory of International Politics (TIP), arguing its positions on change, agent-structure interaction and culture are irrevocably flawed. We argue that many of these criticisms are mispecified, as they overlook the structural-functionalist assumptions of Waltz’s theory. Seen in this light, structural realism specifies mechanisms of change, provides a plausible account of agent-structure interaction; and is less ‘materialist’ and ‘rationalist’ than its critics suppose. Most fundamentally, recognizing Waltz’s sociological commitments reinforces his insight that reductionist theories cannot account for international order. An appreciation of TIP’s structural-functionalist sensibilities also helps us to understand the flaws of the theory, and provides constructivists with a clearer departure point for a reformulated systems theory of international politics.
Developing excellence in nursing and midwifery research
Authors: Wilson-Barnett Jenifer
Published: February 2005

This paper builds on Tierney’s 1998 address to the annual RCN International Nursing Research Conference. It explores criteria for excellence in nursing and midwifery research, differentiating this from ‘cutting edge’ and ‘international’ descriptors. Members of an expert panel were asked to give ideas on how to create excellence and to provide examples of such work, and on how to develop leaders in research. Their inspiration is presented here. The last section of the paper examines the creation of research teams within the current financial strictures.