bluuebunny/crossref_metadata_2025 huggingface dataset:
Esophageal-gastric relaxation reflex in rat: dual control of peripheral nitrergic and cholinergic transmission
Authors: Hermann Gerlinda E. , Travagli R. Alberto , Rogers Richard C.
Published: January 2006

It has long been known that the esophageal distension produced by swallowing elicits a powerful proximal gastric relaxation. Gastroinhibitory control by the esophagus involves neural pathways from esophageal distension-sensitive neurons in the nucleus tractus solitarius centralis (cNTS) with connections to virtually all levels of the dorsal motor nucleus of the vagus (DMV). We have shown recently that cNTS responses are excitatory and primarily involve tyrosine hydroxylase-immunoreactive cells, whereas the DMV response involves both an α1 excitatory and an α2 inhibitory response. In the present study, using an esophageal balloon distension to evoke gastric relaxation (esophageal-gastric reflex, EGR), we investigated the peripheral pharmacological basis responsible for this reflex. Systemic administration of atropine methyl nitrate reduced the amplitude of the gastric relaxation to 52.0 ± 4.4% of the original EGR, whereas NG-nitro-l-arginine methyl ester (l-NAME) reduced it to 26.3 ± 7.2% of the original EGR. Concomitant administration of atropine methyl nitrate and l-NAME reduced the amplitude of the gastric relaxation to 4.0 ± 2.5% of control. This reduction in the amplitude of induced EGR is quite comparable (4.3 ± 2.6%) to that seen when the animal was pretreated with the nicotinic ganglionic blocker hexamethonium. In the presence of bethanechol, the amplitude of the esophageal distension-induced gastric relaxation was increased to 177.0 ± 10.0% of control; administration of l-NAME reduced this amplitude to 19.9 ± 9.5%. Our data provide a clear demonstration that the gastroinhibitory control by the esophagus is mediated via a dual vagal innervation consisting of inhibitory nitrergic and excitatory cholinergic transmission.
Is Equilibrium Point Control Feasible for Fast Goal-Directed Single-Joint Movements?
Authors: Kistemaker Dinant A. , Van Soest Arthur (Knoek) J. , Bobbert Maarten F.
Published: January 2006

Several types of equilibrium point (EP) controllers have been proposed for the control of posture and movement. EP controllers are appealing from a computational perspective because they do not require solving the “inverse dynamic problem” (i.e., computation of the torques required to move a system along a desired trajectory). It has been argued that EP controllers are not capable of controlling fast single-joint movements. To refute this statement, several extensions have been proposed, although these have been tested using models in which only the tendon compliance, force–length–velocity relation, and mechanical interaction between tendon and contractile element were not adequately represented. In the present study, fast elbow-joint movements were measured and an attempt was made to reproduce these using a realistic musculoskeletal model of the human arm. Three types of EP controllers were evaluated: an open-loop α-controller, a closed-loop λ-controller, and a hybrid open- and closed-loop controller. For each controller we considered a continuous version and a version in which the control signals were sent out intermittently. Only the intermittent hybrid EP controller was capable of generating movements that were as fast as those of the subjects. As a result of the nonlinear muscle properties, the hybrid EP controller requires a more detailed representation of static muscle properties than generally assumed in the context of EP control. In sum, this study shows that fast single-joint movements can be realized without explicitly solving the inverse dynamics problem, but in a less straightforward manner than implied by proponents of conventional EP controllers.
Cortico-Cortical Interactions in Spatial Attention: A Combined ERP/TMS Study
Authors: Fuggetta Giorgio , Pavone Enea F. , Walsh Vincent , Kiss Monika , Eimer Martin
Published: January 2006

To gain insight into the neural basis of visual attention, we combined transcranial magnetic stimulation (TMS) and event-related potentials (ERPs) during a visual search task. Single-pulse TMS over right posterior parietal cortex (rPPC) delayed response times to targets during conjunction search, and this behavioral effect had a direct ERP correlate. The early phase of the N2pc component that reflects the focusing of attention onto target locations in a search display was eliminated over the right hemisphere when TMS was applied there but was present when TMS was delivered to a control site (vertex). This finding demonstrates that rPPC TMS interferes with attentional selectivity in remote visual areas.
Force Platform Measurements as Predictors of Falls among Older People – A Review
Authors: Piirtola Maarit , Era Pertti
Published: January 2006

Background: Poor postural balance is one of the major risk factors for falling. A great number of reports have analyzed the risk factors and predictors of falls but the results have for the most part been unclear and partly contradictory. Objective data on these matters are thus urgently needed. The force platform technique has widely been used as a tool to assess balance. However, the ability of force platform measures to predict falls remains unknown. Objective: The purpose of this systematic review was to extract and critically review the findings of prospective studies where force platform measurements have been used as predictors of falls among elderly populations. Methods: The study was done as a systematic literature review. PubMed, the Cochrane Central Register of Controlled Trials, and CINAHL databases from 1950 to April 2005 were used. The review includes prospective follow-up studies using the force platform as a tool to measure postural balance. Results: Nine original prospective studies were included in the final analyses. In five studies fall-related outcomes were associated with some force platform measures and in the remaining four studies associations were not found. For the various parameters derived on the basis of the force platform data, the mean speed of the mediolateral (ML) movement of the center of pressure (COP) during normal standing with the eyes open and closed, the mean amplitude of the ML movement of the COP with the eyes open and closed, and the root-mean-square value of the ML displacement of COP were the indicators that showed significant associations with future falls. Measures related to dynamic posturography (moving platforms) were not predictive of falls. Conclusion: Despite a wide search only a few prospective follow-up studies using the force platform technique to measure postural balance and a reliable registration of subsequent falls were found. The results suggest that certain aspects of force platform data may have predictive value for subsequent falls, especially various indicators of the lateral control of posture. However, the small number of studies available makes it difficult to draw definitive conclusions.
Seasonal Variance in Serum Levels of Vitamin D Determines a Compensatory Response by Parathyroid Hormone: Study in an Ambulatory Elderly Population in Quebec
Authors: Vecino-Vecino Concepción , Gratton Miren , Kremer Richard , Rodriguez-Mañas Leocadio , Duque Gustavo
Published: January 2006

Background: Although the seasonal variance in serum levels of vitamin D in the elderly is well known, its significance on parathyroid hormone (PTH) remains controversial. Objective: To identify the variability and correlation between serum levels of vitamin D and PTH in a sample of community-dwelling elderly patients in the Province of Quebec, Canada, where vitamin D and calcium are supplemented in the food. Methods: Cross-sectional study in an ambulatory elderly population in the Province of Quebec. Samples were analyzed at theMetabolic and Calcium Research Centre, Royal Victoria Hospital, Montreal, Quebec. 256 healthy men and women aged 65–94 (mean age ± SD: 72.8 ± 5.6) were analyzed. Serum levels of25-hydroxyvitamin D (25(OH)D3)and PTH were determined between 1994 and 1999 using commercial radioimmunoassay kits to measure calciotrophic hormones. We examined data in different seasons of the year and observed the behavior of the data through time. A cut-off level of 25 nmol/l for 25(OH)D3 was established to define vitamin D deficiency. A correlation between vitamin D levels vs. PTH levels was also obtained. Results: There is a predominance of females with a 75% of the population. Among them, 32% showed levels of vitamin D <20 nmol/l as compared to 51% of the male population (p < 0.02). A seasonal variance in the levels of vitamin D was observed with the lower levels happening in early spring with a recovery at the end of the summer (p < 0.004). These low levels of vitamin D corresponded with an inverse pattern in the levels of PTH more importantly in early spring. Conclusion: This study not only confirms previous reports that despite vitamin D food supplementation a vitamin D deficiency is still a finding in elderly population in the Northern hemisphere, but also that a compensatory change in PTH levels concurrently occurs with a potential significance on bone strength and risk of fractures.
Challenges and Opportunities of Health Care for the Aging Community in Lithuania
Authors: Lesauskaite Vita , Macijauskiene Jurate , Rader Erin
Published: January 2006

The aim of this paper is to present the Lithuanian experience in creating a geriatric care system with the hope that it can be of some use to other countries undergoing similar transitions and changes. The Lithuanian population is old with 20% of the population being 60 years and older, and 15% being 65 years and older, with the trend toward a rapidly aging society. In 1990, Soviet rule in Lithuania ceased and the country regained its independence. With its recent acceptance into the European Union, the nation has set goals to meet the recommended requirements for the care of the elderly. The changes began with specialist training in gerontology and geriatrics, and were an essential first step to bridge the gap between the real and the future needs. Later, the Geriatric Care System Development Program was approved by the Ministry of Health. Despite its difficult past, Lithuania is confronting the challenges of health and social care of the aging population. It is embracing the opportunities to initiate policies and related measures to meet these challenges, and is potentially setting an example of good practice as a new European community.
Creativity with Dementia Patients
Authors: Hannemann Beat Ted
Published: January 2006

Background: Creative activities could be stimulating for dementia patients. This article gives a review of practical forms of treating dementia patients with art therapeutic indications. It is also a ground for long-term research objective: in brief, I take exception to such a view, contrary to the common belief in the society and some professionals in the healthcare of dementia patients, on the ground that the patients do not have the capacity to improve thier own creativity.Methods: The theory of cognition tells us about the principle of being creative as a basis for human life. This specific principle is effective for the aged as well. In the long-term, the creative potential of old patients will be unblocked in individual and group therapy sessions.Results: Creative activity has been shown to reduce depression and isolation, offering the power of choice and decisions. Towards the end of life, art and creativity offer a path of opening up the windows to people’s emotional interiors.Conclusions: Creative- and art therapy provides possibilities that are mostly indicated to sharpen the capacity of the senses and the patients’ propensity to act themselves. Nonverbal therapy methods, such as painting, music, etc., are able to influence the well-being of the patients positively, within the modern healthcare system in nursing homes. The elderly and some of the dementia patients take the initiative to combine creativity and arts and to define his/her feeling for aesthetical matters. Furthermore, group therapy sessions help against isolation and lack of life perspective and hope.
Mathematical Modeling and Computer Simulation in Blood Coagulation
Authors: Ataullakhanov Fazoil I. , Panteleev Mikhail A.
Published: January 2006

Over the last two decades, mathematical modeling has become a popular tool in study of blood coagulation. The in silico methods were able to yield interesting and significant results in the understanding of both individual reaction mechanisms and regulation of large sections of the coagulation cascade. The objective of this paper is to review the development of theoretical research in hemostasis and thrombosis, to summarize the main findings, and outline problems and possible prospects in the use of mathematical modeling and computer simulation approaches. This review is primarily focused on the studies dealing with: (1) the membrane-dependent reactions of coagulation; (2) regulation of the coagulation cascade, including effects of positive and negative feedback loops, diffusion of coagulation factors, and blood flow.
The Effect of Convective Flows on Blood Coagulation Processes
Authors: Lobanov A.I. , Starozhilova T.K.
Published: January 2006

Two mathematical models of clot growth in the fluid flows have been considered. The first one is the model of embolus growth in a wall-adjacent flow. The effect of hydrodynamic flows on proceeding chemical reactions and the backward effect of the growing clot on the flow are taken into account. The growing thrombus is assumed to be porous and having low permeability, that is in good agreement with experimental data. The exact solutions determining the distribution of a fluid velocity close to the embolus have been used. Numerical analysis of these solutions have demonstrated that hydrodynamic flows can essentially affect the processes of blood coagulation, and consequently on the clot structure. Their presence might lead to the destruction of chemical fronts having a cylindrical symmetry and formation of the so-called chemical spots. The second model describes the initial stage of thrombus growing in the hemorrhage into a natural internal space. It permits accounting for vessel geometry and provides studying the effects of geometric parameters on fluid flows and coagulation processes. The process of thrombus growth is shown to depend on the ratio of typical values of blood velocity in the vessel and rate of chemical reactions.
Intermuscular Interaction between Synergists in Rat Originates from both Intermuscular and Extramuscular Myofascial Force Transmission
Authors: Maas Huub , Meijer Hanneke J.M. , Huijing Peter A.
Published: January 2006

The purpose of the present study is to investigate the origin of mechanical interactions between the rat extensor digitorum longus (EDL) muscle and the grouped tibialis anterior and extensor hallucis longus muscles (TA+EHL). The proximal and distal tendons of EDL as well as the tied distal tendons of TA+EHL were transected and connected to force transducers. Connective tissues at the muscle bellies of the anterior crural compartment were left intact. Supramaximal stimulation of the common peroneal nerve activated all muscles maximally and simultaneously. Length-isometric force characteristics of distal TA+EHL were assessed. Simultaneously, forces exerted at the proximal and distal tendons of EDL, kept at constant muscle-tendon complex length and position, were measured. Intermuscular interaction was tested in two conditions: (a) after full longitudinal compartmental fasciotomy, and (b) after blunt dissection of the intermuscular connective tissue linkages between EDL and TA+EHL. Note that in the latter condition, intermuscular myofascial pathways were eliminated. In the initial condition, lengthening TA+EHL by 12 mm increased proximal (by 0.14 N, i.e. 9.5%) and decreased distal EDL force (by 0.21 N, i.e. 11.8%), despite the fact that EDL muscle-tendon complex length was kept constant. Blunt dissection decreased TA+EHL and distal EDL forces at low TA+EHL lengths only, while proximal EDL force decreased for all TA+EHL lengths tested. The dissection caused no changes in the TA+EHL length effects on proximal EDL force. In contrast, the amplitude of change in the distal EDL force curve decreased significantly (by 39%) subsequent to blunt dissection. It is concluded that mechanical interaction between synergists originates from both intermuscular as well as extramuscular connective tissues. The highest contribution, however, should be ascribed to the extramuscular pathway.
Micromechanical Resonator Array for an Implantable Bionic Ear
Authors: Bachman Mark , Zeng Fan-Gang , Xu Tao , Li G.-P.
Published: January 2006

In this paper we report on a multiresonant transducer that may be used to replace a traditional speech processor in cochlear implant applications. The transducer, made from an array of micromachined polymer resonators, is capable of passively splitting sound into its frequency sub-bands without the need for analog-to-digital conversion and subsequent digital processing. Since all bands are mechanically filtered in parallel, there is low latency in the output signals. The simplicity of the device, high channel capability, low power requirements, and small form factor (less than 1 cm) make it a good candidate for a completely implantable bionic ear device.
Developing a Physical Model of the Human Cochlea Using Microfabrication Methods
Authors: Wittbrodt Michael J. , Steele Charles R. , Puria Sunil
Published: January 2006

Advances in micromachining technology have provided the opportunity to explore possibilities of creating life-sized physical models of the cochlea. The physical model of the cochlea consists of two fluid-filled channels separated by an elastic partition. The partition is micromachined from silicon and uses a 36-mm linearly tapered polyimide plate with a width of 100 µm at the basal end and 500 µm at the apex to represent the basilar membrane. Thicknesses from 1 to 5 µm have been fabricated. Discrete aluminum fibers (1.5 µm in width) are machined to create direction-dependent properties. A 0.5 × 0.5 mm opening represents the helicotrema. The fluid channels are machined from plexiglas using conventional machining methods. A magnet-coil system excites the fluid channel. Measurements on a model with thickness 4.75 µm show a velocity gain of 4 and phase of 3.5 π radians at a location 23 mm from the base. Mathematical modeling using a 3-D formulation confirm the general characteristics of the measured response.
Magnetic Nanoparticles: Inner Ear Targeted Molecule Delivery and Middle Ear Implant
Authors: Kopke Richard D. , Wassel Ronald A. , Mondalek Fadee , Grady Brian , Chen Kejian , Liu Jianzhong , Gibson Don , Dormer Kenneth J.
Published: January 2006

Superparamagnetic iron oxide nanoparticles (SNP) composed of magnetite (Fe3O4) were studied preliminarily as vehicles for therapeutic molecule delivery to the inner ear and as a middle ear implant capable of producing biomechanically relevant forces for auditory function. Magnetite SNP were synthesized, then encapsulated in either silica or poly (D,L,-Lactide-co-glycolide) or obtained commercially with coatings of oleic acid or dextran. Permanent magnetic fields generated forces sufficient to pull them across tissue in several round window membrane models (in vitrocell culture, in vivo rat and guinea pig, and human temporal bone) or to embed them in middle ear epithelia. Biocompatibility was investigated by light and electron microscopy, cell culture kinetics, and hair cell survival in organotypic cell culture and no measurable toxicity was found. A sinusoidal magnetic field applied to guinea pigs with SNP implanted in the middle ear resulted in displacements of the middle ear comparable to 90 dB SPL.
Environmental Micropatterning for the Study of Spiral Ganglion Neurite Guidance
Authors: Ryan Allen F. , Wittig John , Evans Amaretta , Dazert Stefan , Mullen Lina
Published: January 2006

The projection of neuronal processes is guided by a variety of soluble and insoluble factors, which are sensed by a fiber’s growth cone. It is the differential distribution of such guidance cues that determine the direction in which neurites grow. The growth cone senses these cues on a fine scale, using extensible filopodia that range from a few to tens of µm in length. In order to study the effects of guidance cues on spiral ganglion (SG) neurites, we have used methods for distributing both soluble and insoluble cues on a scale appropriate for sensing by growth filopodia. The scale of these methods are at the micro, rather than nano, level to match the sensing range of the growth cone. Microfluidics and transfected cells were used to spatially localize tropic factors within the fluid environment of extending neurites. Micropatterning was used to present neurites with stripes of insoluble factors. The results indicate that differentially distributed permissive, repulsive and stop signals can control the projection of SG neurites. Implications for future micropatterning studies, for SG development and for the growth of deafferented SG dendrites toward a cochlear implant are discussed.
Non-Exercise Activity Thermogenesis
Authors: Levine James A. , Vander Weg Mark W. , Hill James O. , Klesges Robert C.
Published: January 2006

Non-exercise activity thermogenesis (NEAT) is the energy expenditure of all physical activities other than volitional sporting-like exercise. NEAT includes all the activities that render us vibrant, unique, and independent beings such as working, playing, and dancing. Because people of the same weight have markedly variable activity levels, it is not surprising that NEAT varies substantially between people by up to 2000 kcal per day. Evidence suggests that low NEAT may occur in obesity but in a very specific fashion. Obese individuals appear to exhibit an innate tendency to be seated for 2.5 hours per day more than sedentary lean counterparts. If obese individuals were to adopt the lean “NEAT-o-type,” they could potentially expend an additional 350 kcal per day. Obesity was rare a century ago and the human genotype has not changed over that time. Thus, the obesity epidemic may reflect the emergence of a chair-enticing environment to which those with an innate tendency to sit, did so, and became obese. To reverse obesity, we need to develop individual strategies to promote standing and ambulating time by 2.5 hours per day and also re-engineer our work, school, and home environments to render active living the option of choice.
Elevated Homocysteine Reduces Apolipoprotein A-I Expression in Hyperhomocysteinemic Mice and in Males With Coronary Artery Disease
Authors: Mikael Leonie G. , Genest Jacques , Rozen Rima
Published: January 2006

Hyperhomocysteinemia, a risk factor for cardiovascular disease, is caused by nutritional or genetic disturbances in homocysteine metabolism. A polymorphism in methylenetetrahydrofolate reductase (MTHFR) is the most common genetic cause of mild hyperhomocysteinemia. To examine mechanisms by which an elevation in plasma homocysteine leads to vascular disease, we first performed microarray analyses in livers of
Mthfr
-deficient mice and identified differentially expressed genes that are involved in lipid and cholesterol metabolism. Microarrays and RT-PCR showed decreased mRNA for apolipoprotein A (ApoA)-IV and for ApoA-I and increased mRNA for cholesterol 7α hydroxylase (Cyp7A1) in
Mthfr
+/−
mice compared with
Mthfr
+/+
mice. Western blotting revealed that ApoA-I protein levels in liver and plasma of
Mthfr
+/−
mice were 52% and 62% of levels in the respective tissues of
Mthfr
+/+
mice. We also performed Western analysis for plasma ApoA-I protein levels in 60 males with coronary artery disease and identified a significant (
P
<0.01) negative correlation (−0.33) between ApoA-I and plasma homocysteine levels. This cohort also displayed a negative correlation (−0.24,
P
=0.06) between high-density lipoprotein cholesterol and plasma homocysteine. Treatment of HepG2 cells with supraphysiological levels of 5 mmol/L homocysteine reduced peroxisome proliferator-activated receptor (PPAR) α and ApoA-I protein levels and decreased ApoA-I promoter activity. Transfection with a PPARα construct upregulated ApoA-I and MTHFR. Our results suggest that hyperhomocysteinemia may increase risk of atherosclerosis by decreasing expression of ApoA-I and increasing expression of CYP7A1.
Euthyphro's Thesis Revisited
Authors: Dimas Panos
Published: January 2006

It has been an interpretative dogma to condemn Euthyphro's attempt to account for piety in terms of the gods' wishes as one totally repudiated by Socrates, and in itself untenable. Still at 15c8-9 Socrates expresses some scepticism about whether his refutation of Euthyphro's original account of piety in terms of what the gods love has established that it must be abandoned altogether. He then goes on to say that he and Euthyphro ought to investigate again (παλιν σκεπτεoν), from the beginning (εξ αρχηζ), what piety is (15c11-12), which may be taken to imply that Euthyphro's original account should be revisited. Interpreting Socrates' refutation of that account as having shown that it is one he rejects completely implies that no weight should be attached to Socrates' later reservations, even though he exhibits considerable care in expressing them. Unfortunately, as I argue, this interpretative stand has not brought us any closer to understanding the conception of piety Plato may be attributing to Socrates. If only for the purpose of interpretative completeness, we owe it to Plato actually to do as Socrates suggests at the end of the dialogue that one ought to, and revisit Euthyphro's thesis. In this paper, I propose to break ranks with the dogma. Instead, I follow Socrates' recommendation at 15c11 that we should look into what piety is from the beginning, simply to examine whether there are any insights that might be uncovered by doing so.
Nonlinear Viscoelastic Analysis of Composites using Competing Micromechanical Models
Authors: Sridharan Srinivasan
Published: January 2006

Micromechanical models for a study of nonlinear viscoelastic (NVE) response of composite laminae are developed and their performance compared. A single integral constitutive law proposed by Schapery and subsequently generalized to multiaxial states of stress is utilized in the study for the matrix material. This is used in conjunction with a computationally facile scheme in which hereditary strains are computed using a recursive relation suggested by Henriksen. Composite response is studied using two competing micromodels, a simplified square cell model (SSCM) and a finite element based self-consistent cylindrical model (FECM). The algorithm is developed assuming that the material response computations are carried out in a module attached to a general purpose finite element program used for composite structural analysis. It is shown that the SSCM as used in investigations of material nonlinearity can involve significant errors in the prediction of transverse Young’s modulus and shear modulus. The errors in the elastic strains thus predicted are of the same order of magnitude as the creep strains accruing due to viscoelasticity. The FECM on the other hand does appear to perform better both in the prediction of elastic constants and the study of creep response.
Mechanical Properties Evaluation of a Recycled Flax Fiber-reinforced Vinyl Ester
Authors: Rodriguez E. , Alvarez V. A. , Moran J. , Moreno S. , Petrucci R. , Kenny J. M. , Vazquez A.
Published: January 2006

Flax fiber-vinyl ester composites are milled and mixed with virgin matrices to produce recycled composites. The effect of this powder incorporation on the mechanical properties of a thermosetting matrix (vinyl ester) and a thermoplastic matrix (polypropylene) is studied.

In the case of thermosetting matrix, flexural and tensile strength decrease with the addition of powder. For filler contents higher than 50 vol%, the strength reaches a constant value. Flexural and Young’s moduli remain constant for different powder contents.

In the case of thermoplastic matrix, strength and modulus decrease when powder is replaced by fibers. Both, fibers and powder act as reinforcement as moduli increase. Impact properties are improved with the addition of powder and fibers in comparison with the pure matrix.
Modeling of Power-law Fluid Flow Through Fiber Beds
Authors: Lundstrom T. Staffan , Sundlof Henrik , Holmberg J. Anders
Published: January 2006

An apparent permeability of an idealized unidirectional reinforcement is derived for power-law fluid flow perpendicular to the fibers. The reinforcement consists of regularly ordered, parallel fibers arranged in a quadratic or hexagonal pattern. The expression is obtained starting from first principles for low Reynolds number, incompressible and isothermal flow and is expressed in terms of the radius of the fibers, the fiber volume fraction, and the power-law index. The model is successfully verified with computational fluid dynamic simulations.
Farewell to Childcare?
Authors: Moss Peter
Published: January 2006

The paper argues that in the early years field England has started a process of change from what is termed a ‘childcare discourse’ to a ‘pedagogical discourse’, the former representing a fragmented approach to services for children, the latter the sort of integrated and holistic approach to which theEvery Child Matterspolicy aspires. It considers the experience of countries which have already made the turn to a pedagogical discourse, what this change might mean in the area of school-age provision and the barriers to England completing the process of change, which requires restructuring to be grounded in rethinking.
Rationality in Collective Action
Authors: Gilbert Margaret
Published: January 2006

Collective action is interpreted as a matter of people doing something together, and it is assumed that this involves their having a collective intention to do that thing together. The account of collective intention for which the author has argued elsewhere is presented. In terms that are explained, the parties are jointly committed to intend as a body that such-and-such. Collective action problems in the sense of rational choice theory—problems such as the various forms of coordination problem and the prisoner’s dilemma—are then considered. An explanation is given of how, when such a problem is interpreted in terms of the parties’ inclinations, a suitable collective intention resolves the problem for agents who are rational in a broad sense other than the technical sense of game theory.
Cross-sectional Analysis of Guidelines on Cardiovascular Disease Risk Factors: Going to Meet the Inconsistencies
Authors: van Wyk Jacobus T. , van Wijk Marc A. M. , Moorman Peter W. , van der Lei Johan
Published: January 2006

Objective. To identify the possible inconsistency of statements among the practice guidelines of the Dutch College of General Practitioners (DCGP) with respect to the management of risk factors for cardiovascular disease (CVD). Methods. Cross-sectional analysis of all electronically available DCGP practice guidelines dealing with CVD risk factor management for statement inconsistencies and reference inconsistencies.Results. Six DCGP guidelines out of 74 electronically available guidelines had either CVD or CVD risk factors as the subject of the guideline. Eight statement inconsistencies-were found, and for each statement inconsistency, a reference inconsistency was present.Conclusions. Given that inconsistencies were found, the authors recommend that organizations that maintain a set of guidelines update the guidelines using a cross-sectional analysis of guidelines. Inconsistencies between guidelines might lead to physicians being unintentionally noncompliant with guideline recommendations.
An Alternative Approach to Reducing the Costs of Patient Care? A Controlled Trial of the Multi-Disciplinary Doctor-Nurse Practitioner (MDNP) Model
Authors: Ettner Susan L. , Kotlerman Jenny , Afifi Abdelmonem , Vazirani Sondra , Hays Ron D. , Shapiro Martin , Cowan Marie
Published: January 2006

Objective. Hospitals adapt to changing market conditions by exploring new care models that allow them to maintain high quality while containing costs. The authors examined the net cost savings associated with care management by teams of physicians and nurse practitioners, along with daily multidisciplinary rounds and postdischarge patient follow-up. Methods. One thousand two hundred and seven general medicine inpatients in an academic medical center were randomized to the intervention versus usual care. Intervention costs were compared to the difference in nonintervention costs, estimated by comparing changes between preadmission and postadmission in regression-adjusted costs for intervention versus usual care patients. Intervention costs were calculated by assigning hourly costs to the time spent by different providers on the intervention. Patient costs during the index hospital stay were estimated from administrative records and during the 4-month follow-up by weighting selfreported utilization by unit costs. Results. Intervention costs were $1187 per patient and associated with a significant $3331 reduction in nonintervention costs. About $1947 of the savings were realized during the initial hospital stay, with the remainder attributable to reductions in postdischarge service use. After adjustment for possible attrition bias, a reasonable estimate of the cost offset was $2165, for a net cost savings of $978 per patient. Because health outcomes were comparable for the 2 groups, the intervention was cost-effective. Conclusions. Wider adoption of multidisciplinary interventions in similar settings might be considered. The savings previously reported with hospitalist models may also be achievable with other models that focus on efficient inpatient care and appropriate postdischarge care.
Autologous Chondrocyte Implantation Postoperative Care and Rehabilitation
Authors: Hambly Karen , Bobic Vladimir , Wondrasch Barbara , Van Assche Dieter , Marlovits Stefan
Published: January 2006

Autologous chondrocyte implantation is an advanced, cell-based orthobiological technology used for the treatment of chondral defects of the knee. It has been in clinical use since 1987 and has been performed on 12 000 patients internationally; but despite having been in clinical use for more than 15 years, the evidence base for rehabilitation after autologous chondrocyte implantation is notably deficient. The authors review current clinical practice and present an overview of the principles behind autologous chondrocyte implantation rehabilitation practices. They examine the main rehabilitation components and discuss their practical applications within the overall treatment program, with the aim of facilitating the formulation of appropriate, individualized patient rehabilitation protocols for autologous chondrocyte implantation.
Volume Changes in the Menisci and Articular Cartilage of Runners
Authors: Kessler Markus A. , Glaser Christian , Tittel Sylvia , Reiser Maximilian , Imhoff Andreas B.
Published: January 2006

Background

Articular cartilage contributes to transferring enormous loads as uniformly as possible from one skeletal segment to the next. Whether it manages this task when subjected to the high repetitive loading cycles occurring during long-distance running and can remain intact is still the topic of controversy.

Purpose

To investigate the changes in cartilaginous volumes of the tibia, patella, and medial and lateral menisci after extreme dynamic loading as occurs in long-distance runners.

Study Design

Controlled laboratory study.

Methods

Forty-eight knees of male athletes were studied (38 ± 14 years). The subjects ran around a predetermined and precisely measured course (5, 10, 20 km), the beginning and end of the run being in the magnetic resonance imaging investigation room. The scan protocol was 60-minute rest period, first measurement, run, 3-minute delay, and second measurement.

Results

Overall, there were significant reductions in volume (P < .05) for the patella, tibia, and menisci. There was evidence of significant change after a running distance of 5 km. A further statistical reduction of the volume could only be demonstrated for the medial meniscus after 10 and 20 km.

Conclusion

Tibial, patellar, and meniscal cartilaginous volumes show not only load-dependent volume changes but also an asymptotic curve. This is the first time that meniscal volume changes due to loading have been used as an indicator of the important mechanical contribution that the menisci make to sustaining the knee during repetitive loading.

Clinical Relevance

On the basis of the results of this study, the authors assume that the cartilage is able to adapt well to the loads caused by running.
The Relationship between Menstrual Cycle Phase and Anterior Cruciate Ligament Injury
Authors: Beynnon Bruce D. , Johnson Robert J. , Braun Stuart , Sargent Mike , Bernstein Ira M. , Skelly Joan M. , Vacek Pamela M.
Published: January 2006

Background

Female athletes suffer a greater incidence of anterior cruciate ligament tears compared with male athletes when participating in common sports; however, very little is known about the factors that explain this disparity.

Study Design

Case-control study; Level of evidence, 3.

Methods

Female recreational alpine skiers with an anterior cruciate ligament rupture and age-matched control skiers provided a serum sample and self-reported menstrual history data immediately after injury. Both serum concentrations of progesterone and menstrual history were then used to group subjects into either preovulatory or postovulatory phases of the menstrual cycle.

Results

Analysis of serum concentrations of progesterone revealed that alpine skiers in the preovulatory phase of the menstrual cycle were significantly more likely to tear their anterior cruciate ligaments than were skiers in the postovulatory phase (odds ratio, 3.22; 95% confidence interval, 1.09-9.52; P = .027). Analysis of menstrual history data found similar results, but the difference was not statistically significant (odds ratio, 2.38; 95% confidence interval, 0.86-6.54; P = .086).

Conclusion

The likelihood of sustaining an anterior cruciate ligament injury does not remain constant during the menstrual cycle; instead, the risk of suffering an anterior cruciate ligament disruption is significantly greater during the preovulatory phase of the menstrual cycle compared with the postovulatory phase.

Clinical Relevance

Phase of menstrual cycle may be one of the risk factors that influence knee ligament injury among female alpine skiers. The findings from this study should be considered in subsequent studies designed to identify persons at risk for anterior cruciate ligament injury and to develop intervention strategies.
Anatomical Double-Bundle Anterior Cruciate Ligament Reconstruction after Valgus High Tibial Osteotomy
Authors: Kilger Robert H. P. , Stehle Jens , Fisk Jesse A. , Thomas Maribeth , Miura Kazutomo , Woo Savio L-Y.
Published: January 2006

Background

Although anatomical double-bundle anterior cruciate ligament reconstruction can successfully restore normal knee biomechanics for knees with typical varus-valgus alignment, the efficacy of the same reconstruction method for knees after a valgus high tibial osteotomy is unclear.

Hypothesis

Anatomical double-bundle anterior cruciate ligament reconstruction for valgus knees after a high tibial osteotomy cannot restore normal knee kinematics and can result in abnormally high in situ forces in the ligament graft.

Study Design

Controlled laboratory study.

Methods

Ten cadaveric knees were subjected to valgus high tibial osteotomy followed by an anatomical double-bundle anterior cruciate ligament reconstruction. The valgus knees were tested using a robotic/universal force-moment sensor system before and after the ligament reconstruction. The knee kinematics in response to anterior tibial load and combined rotatory loads, as well as the corresponding in situ forces of the anterior cruciate ligament bundles and grafts, were compared between the ligament-intact and ligament-reconstructed valgus knees.

Results

After reconstruction, the anterior tibial translation and internal tibial rotation for the valgus knee decreased approximately 2 mm and 2°, respectively, at low flexion angles compared with those of the anterior cruciate ligament–intact knee (P < .05). The in situ forces in the posterolateral graft became 56% to 200% higher than those in the posterolateral bundle of the intact anterior cruciate ligament (P < .05).

Conclusion

Performing an anatomical double-bundle anterior cruciate ligament reconstruction on knees after valgus high tibial osteotomy may overconstrain the knee and result in high forces in the posterolateral graft, which could predispose it to failure.

Clinical Relevance

Modifications of anterior cruciate ligament reconstruction procedures to reduce posterolateral graft force may be needed for valgus knees after a high tibial osteotomy.
The Effects of Medialization and Anteromedialization of the Tibial Tubercle on Patellofemoral Mechanics and Kinematics
Authors: Ramappa Arun J. , Apreleva Maria , Harrold Fraser R. , Fitzgibbons Peter G. , Wilson David R. , Gill Thomas J.
Published: January 2006

Background

Medialization and anteromedialization of the tibial tubercle are used to correct patellar subluxation in adults.

Purpose

To compare the effects of the 2 osteotomies on patellofemoral joint contact pressures and kinematics.

Study Design

Controlled laboratory study.

Methods

Tibial tubercle osteotomies were performed on 10 cadaveric human knees. The knees were tested between 0° and 90° of flexion while dynamic patellofemoral joint contact pressure and kinematic data were simultaneously obtained. Four conditions were tested: normal knee alignment, simulated increased Q angle, postmedialization of the tibial tubercle, and postanteromedialization of the tubercle.

Results

An increased Q angle laterally translated the patella, shifted force to the lateral facet, and increased patella contact pressures. Both medialization and anteromedialization partially corrected the abnormal contact pressures. Medialization partially corrected the shift of force to the lateral facet induced by an increased Q angle, whereas the anteromedialization could not. Both medialization and anteromedialization corrected the patella maltracking.

Conclusion

Medialization and anteromedialization are equivalent in their ability to correct abnormal patellar mechanics and kinematics.
Modiano's stylo
Authors: Nettelbeck Colin
Published: January 2006

Although various critics have drawn attention to the importance of cinema in Patrick Modiano's writing, there has so far been no substantial or systematic account of the phenomenon, and a first goal of this study is to remedy that omission. Secondly, in a period when the momentum of cultural narrative practice has been heading more in the direction of cinema than of literature, Modiano's work offers a more general insight into some of the cultural and artistic tensions between literature and cinema in contemporary France. This study argues that, rather than being in conflict with cinema, Modiano's narratives help define a certain modus vivendi, a way for literature to participate with cinema in what appears as a new and more variegated space in French culture.
Men and Horses
Authors: Weil Kari
Published: January 2006

As the modern domain of sport put pressure on the corporeal manifestations of class, gender and race, French sports enthusiasts of the fin-de-siècle promoted equestrianism for producing, if not for revealing, true French manhood. Such manhood was also projected onto the thoroughbred horse, but in a contradictory way since the thoroughbred could refer both to a superior, pure race – an aristocracy – and to a superiority achieved through scientific engineering or training – a bourgeoisie. The attempts to promote equestrianism, for competition or the circus, like efforts to lay claim to the thoroughbred, moreover, implicated both aristocrats and bourgeois in a performative dynamic of bodily display that worked against the normative masculinity riding was said to promote. In the face of such risks of exhibitionism, however, the performance of men and horses together helped to refashion the meaning of virility, as of male spectacle.
Reliability and Validity of a Spanish Version of the Posttraumatic Growth Inventory
Authors: Weiss Tzipi , Berger Roni
Published: January 2006

Objectives. This study was designed to adapt and validate a Spanish translation of the Posttraumatic Growth Inventory (PTGI) for the assessment of positive life changes following the stressful experiences of immigration. Method. A cross-cultural equivalence model was used to pursue semantic, content, conceptual, and technical equivalence. Translation teams and back translations were employed for semantic and content equivalence. Conceptual and technical equivalence were assessed through field-testing the reliability and factor structure of the translated PTGI in a sample of 100 Latina immigrants. Results. The translated version was highly reliable. Factor analysis failed to replicate the original five factors but the three factors identified were consistent with the conceptual underpinnings of the PTGI and another translated version. Conclusions. Semantic, content, conceptual, and technical equivalence of the Spanish version of the PTGI were supported and thus its valid use for research and practice with the study population.
The Effectiveness of Community Practice Interventions: A Review of the Literature
Authors: Ohmer Mary L. , Korr Wynne S.
Published: January 2006

Objective: Evidence-based practice is becoming increasingly important in social work and community practice. The authors reviewed existing research to assess the level of evidence available to guide community practice. Method: The authors conducted a review of the literature on community practice intervention research from 1985 to 2002 using several databases, search engines, and personal contact with researchers. The authors found 269 articles published from 1985 to 2001. Fifty-eight were quantitative and combined quantitative and qualitative studies, of which 20 were intervention studies. Conclusions: The search revealed a relatively small number of quantitative intervention studies using experimental or statistical controls (9), which suggests the need for a consideration of how to develop the evidence base for community practice. Implications for social work practice are also discussed.
The Art of Evidence-Based Practice
Authors: Pollio David E.
Published: January 2006

The purpose of this article is to discuss evidence-based practice (EBP) from the perspective of a self-identified evidence-based practitioner. Discussion of EBP includes choosing an initial intervention and evaluation procedures, the iterative process of rechoosing and refining an intervention over the treatment life span, and the importance of evidence within the specific clinical situation. Two illustrative case studies are presented. Practice principles include (a) explaining EBP clearly, including an ability to deconstruct key elements; (b) creating an evaluation that yields useful outcome data for practitioner and client and is realistic given the characteristics of the client system; (c) refining intervention and evaluation efforts, based on increased knowledge of the client system and as their willingness to participate changes; and (d) understanding relevant evidence about specific techniques, incorporating evidence developed as part of the intervention, and being critical consumers of both types of evidence in specific situations with clients and client systems.