bluuebunny/crossref_metadata_2025 huggingface dataset:
Vegetation control and site preparation affect patterns of shoot elongation for 3-year-old loblolly pine
Authors: Allen H. Lee , Wentworth Thomas R.
Published: July 2007

Effects of vegetation control and site preparation on the magnitude, morphology, and phenology of loblolly pine (Pinustaeda L.) height growth were investigated duing the third growing season following planting in the Piedmont of North Carolina. Biweekly measurements were made of shoot elongation (by flush) throughout the growing season on a subsample of trees within three replicated plots receiving a factorial combination of site preparation (chop versus shear, pile, disk) and weed control (none, partial control with herbicide, and complete control by hand weeding) treatments. Cumulative height growth on the most intensively treated plots was twice that found on the chopped-only plots, with weed control having a more pronounced positive effect than intensive site preparation. Superior height growth resulted principally from greater length per flush but also from an increased number of flushes. Trees on plots where vegetation was controlled averaged between four and five flushes compared with trees on chopped-only plots, which averaged three flushes. As growth rate of one flush slowed, growth rate of the subsequent flush accelerated, resulting in a rather uniform elongation rate for the shoot apex throughout most of the growing season. Treatment effects on the seasonal distribution of growth and on growing season length were minimal. Thus, intensive culture influenced shoot growth rates and morphology, but not phenology. Apparently the effect of intensive culture was to improve the availability of limited environmental resources and, consequently, to increase growth rate throughout the growing season.
Site preparation burning to improve southern Appalachian pine–hardwood stands: vegetation composition and diversity of 13-year-old stands
Authors: Clinton B.D. , Vose J.M. , Swank W.T.
Published: July 2007

Stand restoration of low-quality, mixed pine–hardwood ecosystems containing a Kalmialatifolia L. dominated understory, through cutting, burning, and planting of Pinusstrobus L., is common on xeric southern Appalachian forest sites. We examined the effects of this treatment on early vegetation composition and diversity. Four 13-year-old stands were examined. Two of the four stands were mechanically released at age 6. Density and basal area were estimated for understory and overstory components, and density and percent cover for the herb component. Species diversity (Shannon–Wiener index) was estimated and comparisons were made between layers, sites, and treatments (release vs. nonrelease). Diversity estimates were 3.19, 1.74, and 2.45 for the herb, shrub, and overstory layers, respectively, across all sites and treatments. For perspective, comparisons were made with an untreated reference stand that was typical of stands receiving site preparation burning in the southern Appalachians. Overstory and herb diversity estimates were significantly lower for the reference stand than for the 13-year-old stands.
Does nursery production reduce antiherbivore defences of white spruce? Evidence from feeding experiments with snowshoe hares
Authors: Rodgers A.R. , Williams D. , Sinclair A.R.E. , Sullivan T.P. , Andersen R.J.
Published: July 2007

Previous studies indicate that snowshoe hares (Lepusamericanus Erxleben) readily browse nursery-grown white spruce (Piceaglauca (Moench) Voss) seedlings but tend to avoid naturally regenerating juvenile trees. We confirmed these observations in feeding trials with snowshoe hares and investigated several possible explanations for this phenomenon. In vitro digestibilities of nursery-grown and naturally regenerating white spruce seedlings were similar, indicating similar contents of acid detergent fibre. Thus, it is unlikely that snowshoe hares are better able to extract nutrients from nursery-grown seedlings than from naturally regenerating white spruce. We suggest that snowshoe hares prefer to feed on nursery-grown seedlings because they contain less camphor (a specific compound in white spruce shown to deter feeding by hares) and have higher nutritional value (i.e., nitrogen) than naturally regenerating plants.
Impact of ash yellows mycoplasmalike organisms on radial growth of naturally infected white, green, and velvet ash
Authors: Sinclair Wayne A. , Griffiths Helen M. , Treshow Michael
Published: July 2007

Growth of white ash (Fraxinusamericana L.), green ash (Fraxinuspennsylvanica Marsh.), and velvet ash (Fraxinusvelutina Torr.) as related to infection by ash yellows mycoplasmalike organisms (MLOs) was assessed by diagnosing and grouping trees as MLO infected or healthy and comparing their previous annual radial growth over periods of 9–22 years. White ash and green ash 17–30 years old were studied on two sites per species in central New York State. Velvet ash 30–90 years old was studied in Zion National Park, Utah. MLOs were detected by fluorescence microscopy. Widths of growth rings were measured on increment cores or cross sections of main stems. Growth trends of diseased and healthy groups of white ash and green ash diverged when ash stands were 12–21 years old. In the fifth year after divergence, the unweighted average growth of diseased green ash across two plots was 70% of that of healthy trees. For white ash, the corresponding average was 61%. In white ash tested annually for MLO infection, growth reduction preceded MLO detection by an average of 1 year. Velvet ash did not sustain MLO-associated growth reduction. This species may be tolerant of infection by ash yellows MLOs.
Predicting the stage of decay of decomposing leaves by near infrared reflectance spectroscopy
Authors: Gillon Dominique , Joffre Richard , Dardenne Pierre
Published: July 2007

To study mineral cycling in forest ecosystems, it is essential to know the decomposition rate of the litter. This study attempted to predict directly, by near infrared reflectance spectroscopy, the stage of decomposition of leaf litter expressed as the percentage of ash-free litter mass remaining (LMR). Leaf litter of 10 different species, with varied initial compositions and at different stages of decomposition produced by incubation in the laboratory under controlled conditions, were used in this study. The LMR calibrations were carried out on half of the samples of the various populations (all species, woody species, broad-leaved species, trees, broad-leaved trees, oaks, deciduous trees, and evergreen trees). The standard error of cross validation varied between 1.69 and 3.01. Predictions were carried out on the other half of the samples of each population; the standard error of prediction varied between 2.35 and 3.77, with a r2 (coefficient of determination) of 0.97 to 0.99. The calibration equations obtained from the laboratory samples were applied to samples that had decomposed in the field in litter bags. The standard error of prediction varied between 4.46 and 5.97, with a r2 of 0.90 to 0.93. Near infrared reflectance spectroscopy thus provides a direct prediction of the LMR in leaf litter of different species, during the decomposition stage studied (i.e., between 100 and 20% of litter mass remaining). The possibilities of using near infrared reflectance spectroscopy in decomposition studies are discussed.
Modelling wood density in European oak (Quercuspetraea and Quercusrobur) and simulating the silvicultural influence
Authors: Zhang Shu-Yin , Owoundi Ruben Eyono , Nepveu Gérard , Mothe Frédéric , Dhôte Jean-François
Published: July 2007

Wood density in relation to cambial age and ring width was studied in 23 trees of European oak (Quercuspetraea (Matt) Liebl. and Quercusrobur L.) from northeast France, and based on these relationships, a model predicting intratree wood density through cambial age and ring width was developed. Wood density is closely correlated with both cambial age and ring width, but its relationships with cambial age and ring width, to some extent, vary from tree to tree. The variation, however, does not show an appreciable pattern with tree height. The model developed is able to predict satisfactorily the average wood density of growth rings in European oak, and to explain the main part of the variation in wood density of individual trees. Furthermore, the model appears also possible to predict the average density of a given small piece of wood from any part of the merchantable bole of the trees. A general model, however, accounts for a relatively low percentage of the variation because there is large intertree variability of wood density in the species. The simulation results reveal that the dynamic silviculture applied to European oak might result in the production of denser and more uniform (in the sense of the radial variation of wood density) wood, compared with classical silviculture.
Average relative stem profile comparisons for three size classes of Caribbean pine
Authors: Allen Paul J.
Published: July 2007

A method for determining and comparing average relative stem profiles is described. Under-bark diameters at several points along the stem and the total heights were measured on 572 sample trees of Caribbean pine (Pinuscaribaea Morelet var. hondurensis Barrett & Golfari). For each tree, the total volume and the diameters under bark at several consistent relative positions along the stem (viz. 0.10–0.50 in increments of 0.05) were interpolated. The trees were categorised into three size classes depending on volume. For each tree, a true form factor corresponding to each interpolated relative position was calculated. These form factors were regressed on volume for each size class to determine the most appropriate position along the stem for use in calculating the relative diameters. A polynomial model was fitted to each size class, using relative diameter as the dependent variable and powers of relative height as the independent variables. Differences between the three equations describing the mean relative profiles were statistically significant. Mean errors for the relative diameters are also presented to indicate the accuracy of the three equations.
Allozyme variation of the endangered Florida torreya (Torreyataxifolia)
Authors: Schwartz Mark W.
Published: July 2007

Torreyataxifolia Arn. is an endangered conifer restricted to ravine slopes along the Apalachicola River in northern Florida. The species began a decline in the 1950s that has resulted in fewer than 1500 trees remaining extant in the wild. Allelic variation was examined for 189 trees throughout its range. The species is characterized by low overall levels of genetic variation: seven of 20 loci were variable; each polymorphic locus had no more than two alleles; mean heterozygosity (He) was 0.064. Over 78% of this measured genetic variation was found within populations; no spatial pattern was detected in the remaining variation between populations within drainage regions, across drainage regions, or across soil types. This genetic information was used to plan tissue collection for a permanent offsite population.
PROPERTIES OF THE CASCADED LATTICE BOLTZMANN AUTOMATON
Authors: GEIER MARTIN , GREINER ANDREAS , KORVINK JAN G.
Published: July 2007

The theory of the lattice Boltzmann automaton is based on a moment transform which is not Galilean invariant. It is explained how the central moments transform, used in the cascaded lattice Boltzmann method, overcomes this problem by choosing the center of mass coordinate system as the frame of reference. Galilean invariance is restored and the form of the kinetic theory is unaffected. Conservation laws are not compromised by the high order polyinomials in the equilibrium distribution arising from the central moment transform.

Two sources of instabilities in lattice Boltzmann simulations are discussed: negative numerical viscosity due to insufficient Galilean invariance and aliasing. The cascaded lattice Boltzmann automaton overcomes both problems. It is discussed why aliasing is unavoidable in lattice Boltzmann methods that rely on a single relaxation time. An appendix lists the complete scattering operator of the D2Q9 cascaded lattice Boltzmann automaton.
A LATTICE BOLTZMANN METHOD FOR COMPUTATION OF AEROACOUSTIC INTERACTION
Authors: KAM E. W. S. , LEUNG R. C. K. , SO R. M. C. , LI X. M.
Published: July 2007

This paper reports a study of the ability of an improved LBM in replicating acoustic interaction. With a BGK model with two relaxation times approximating the collison term, the improved LBM is shown not only able to recover the equation of state, but also replicates the specific heat ratio, the fluid viscosity and thermal conductivity correctly. With these improvements, the recovery of full set of unsteady compressible Navier-Stokes equations is possible. Two complex aeroacoustic interaction problems, namely the interaction of three fundamental aeroacoustic pulses and scattering of short wave by a zero circulation vortex, are calculated. The LBM solutions are compared with DNS results. In the first case it has been shown that the improved LBM is as effective as the DNS in simulating aeroacoustic interaction of three pulses. Both methods obtain essentially same results using same truncated domains. In the scattering problem, LBM is able to replicate the directivity of scattered acoustic wave from the vortex but it does not accurately reproduce the symmetry as calculated using DNS.
NUMERICAL SIMULATION OF ISOTHERMAL AND THERMAL TWO-PHASE FLOWS USING PHASE-FIELD MODELING
Authors: TAKADA NAOKI , TOMIYAMA AKIO
Published: July 2007

For interface-tracking simulation of two-phase flows in various micro-fluidics devices, we examined the applicability of two versions of computational fluid dynamics method, NS-PFM, combining Navier-Stokes equations with phase-field modeling for interface based on the van der Waals-Cahn-Hilliard free-energy theory. Through the numerical simulations, the following major findings were obtained: (1) The first version of NS-PFM gives good predictions of interfacial shapes and motions in an incompressible, isothermal two-phase fluid with high density ratio on solid surface with heterogeneous wettability. (2) The second version successfully captures liquid-vapor motions with heat and mass transfer across interfaces in phase change of a non-ideal fluid around the critical point.
A GENERAL MULTIPLE-RELAXATION-TIME BOLTZMANN COLLISION MODEL
Authors: SHAN XIAOWEN , CHEN HUDONG
Published: July 2007

We formulate a simple extension to the Bhatnagar-Gross-Krook collision model by expanding the distribution function in Hermite polynomials and assigning a relaxation time to each hydrodynamic moment. By discretizing the velocity space, multiple-relaxation-time lattice Boltzmann models can be constructed. The transport coefficients are analytically calculated and numerically verified. At the lowest order, allowing different relaxation rates for the second and third Hermite components results in a variable Prandtl number. Comparing with the previously proposed multiple-relaxation-time lattice Boltzmann models, the present formulation is general in the sense that it is independent of the underlying lattice structure and does not require a procedure for transformation of base vectors.
RAPIDITY DEPENDENCE OF CHARGE FLUCTUATIONS AND CORRELATIONS IN HADRONIC AND NUCLEAR COLLISIONS
Authors: FENG AOQI , LI NA , FU JINGHUA , WU YUANFANG
Published: July 2007

Size and position of rapidity window dependence of charge fluctuations and correlations are studied by PYTHIA and RQMD models for hadron–hadron and nucleus–nucleus collisions respectively. The results show that all the measures for charge fluctuations and correlations depend on the size of central rapidity windows and most of them depend on the position of the rapidity windows, which is not expected. Only charge balance function in hadron–hadron collisions is independent of the position of rapidity window, i.e. boost-invariant, in consistent with corresponding experimental data, while charge fluctuations measured by D(Q) is not boost-invariant in contrast to the experimental data. The measures for three kind of charge correlations (R++, R--, R+-) show a good account for the behavior of charge correlations and global charge conservation in longitudinal phase space in both PYTHIA and RQMD.
Anti-inflammatory properties ofLactobacillus gasseriexpressing manganese superoxide dismutase using the interleukin 10-deficient mouse model of colitis
Authors: Carroll Ian M. , Andrus Jason M. , Bruno-Bárcena José M. , Klaenhammer Todd R. , Hassan Hosni M. , Threadgill Deborah S.
Published: July 2007

Emerging evidence has implicated reactive oxygen species (ROS) in the pathogenesis of inflammatory bowel disease (IBD). Although intestinal epithelial cells produce the ROS-neutralizing enzyme superoxide dismutase (SOD), the protein and activity levels of copper/zinc (Cu/Zn) and manganese (Mn) SOD are perturbed in inflamed tissues of IBD patients. Thus we investigated the ability of MnSOD from Streptococcus thermophilus to reduce colitis symptoms in interleukin (IL) 10-deficient mice using Lactobacillus gasseri as a delivery vehicle. Cohorts of 13–15 IL-10-deficient mice were left untreated or supplemented with native L. gasseri or L. gasseri expressing MnSOD for 4 wk. Colonic tissue was collected and inflammation was histologically scored. The presence of innate immune cells was investigated by immunohistochemistry and the host antioxidant response was determined by quantitative PCR. It was demonstrated that L. gasseri was stably maintained in mice for at least 3 days. L. gasseri producing MnSOD significantly reduced inflammation in IL-10-deficient mice compared with untreated controls ( P < 0.05), whereas the anti-inflammatory effects of both native and MnSOD producing L. gasseri were more pronounced in males. The anti-inflammatory effects of L. gasseri were associated with a reduction in the infiltration of neutrophils and macrophages. Transcripts of antioxidant genes were equivalent in colonic tissues obtained from control and probiotic-treated IL-10-deficient mice. This study demonstrates that L. gasseri producing MnSOD has significant anti-inflammatory activity that reduces the severity of colitis in the IL-10-deficient mouse.
Single muscle fiber function with concurrent exercise or nutrition countermeasures during 60 days of bed rest in women
Authors: Trappe Scott , Creer Andrew , Slivka Dustin , Minchev Kiril , Trappe Todd
Published: July 2007

There is limited information on skeletal muscle properties in women with unloading and countermeasure programs to protect the unloading-induced atrophy. The current investigation tested the hypothesis that a concurrent aerobic and resistance exercise training program would preserve size and contractile function of slow- and fast-twitch muscle fibers. A secondary objective was to test the hypothesis that a leucine-enriched high-protein diet would partially attenuate single fiber characteristics. Vastus lateralis muscle biopsies were obtained before and on day 59 of bed rest from a control (BR; n = 8), nutrition (BRN; n = 8), or exercise (BRE; n = 8) group. Single muscle fibers were studied for diameter, peak force (Po), contractile velocity, and power. Those in the BR group had a decrease ( P < 0.05) in myosin heavy chain (MHC) I diameter (−14%), Po(−35%), and power (−42%) and MHC IIa diameter (−16%) and Po(−31%; P = 0.06) and an increase ( P < 0.05) in MHC hybrid fibers. Changes in size and function of MHC I (−19 to −44%) and IIa (−21% to −30%) fibers and MHC distribution in BRN individuals were similar to results in the BR group. In BRE conditions, MHC I and IIa size and contractile function were preserved during bed rest. These data show that the concurrent exercise program preserved the myocellular profile of the vastus lateralis muscle during 60-day bed rest. To combat muscle atrophy and function with long-term unloading, the exercise prescription program used in this study should be considered as a viable training program for the upper leg muscles, whereas the nutritional intervention used cannot be recommended as a countermeasure for skeletal muscle.
Physician Recommendations Regarding SIDS Risk Reduction: A National Survey of Pediatricians and Family Physicians
Authors: Moon Rachel Y. , Kington Marit , Oden Rosalind , Iglesias Joana , Hauck Fern R.
Published: July 2007

Background: Sudden infant death syndrome (SIDS) is a leading cause of death among infants. Recently, new SIDS risk factors have emerged. Objective: To determine knowledge and recommendations of pediatricians and family physicians regarding SIDS-relevant practices. Methods: Cross-sectional survey of 3005 pediatricians and family physicians. Results: Of the 783 respondents, pediatricians comprised 64% and females 52%; 78% recognized supine as the recommended sleep position; 69% recommended supine. Almost all physicians recommended a firm mattress, 82% recommended a crib or bassinet, and 42% recommended a separate room for infants; 63% had no preference about or did not recommend restricting pacifier use. Pediatricians were more likely to discuss infant sleep position and room sharing at every well-child visit. Conclusions: Knowledge about recommended infant sleep position is relatively high, but there are gaps in physician knowledge regarding safe sleep recommendations. Greater dissemination of information is required, and barriers to implementation need to be identified and addressed.
Pharmacological Treatment of Anorexia Nervosa: A Retrospective Study in Preadolescents and Adolescents
Authors: Rossi G. , Balottin U. , Rossi M. , Chiappedi M. , Fazzi E. , Lanzi G.
Published: July 2007

To date, studies addressing the role of pharmacotherapy in the treatment of anorexia nervosa are limited, especially in childhood and adolescence. The aim of this retrospective naturalistic study was to evaluate the efficacy and safety of pharmacotherapy in 19 anorexic preadolescents and adolescents referred, for the first time, to a specialist psychiatry unit. Almost all the patients showed an improvement both in their eating behaviors, and in their mood and obsessive symptoms. No evidence was found of dangerous adverse events. Combined with a multidisciplinary approach that includes nutritional rehabilitation and psychotherapy, adjunctive pharmacotherapy may be useful in addressing both eating disorder psychopathology and comorbid psychiatric disorders.
Importance-Performance Analysis of Guest Technologies in the Lodging Industry
Authors: Beldona Srikanth , Cobanoglu Cihan
Published: July 2007

An assessment of how hotel guests view in-room technology compared the importance of those technologies to how they perform. Based on 265 responses, this importance-performance analysis indicates that important basic technologies like in-room temperature controls and alarm clocks fail to perform in the way guests want, while relatively new technologies like plasma screen TVs and in-room printers and faxes are less important but perform well when they are in place. In addition, the study finds that internet access is an integral part of the lodging product.
Facile Fabrication of Spindle-shaped β-FeOOH/PAN-amidhydrazone/Ag Core-Shell Particles in Organic Solvent
Authors: Lei Zhongli , Zhao Junchao , Liu Yalan
Published: July 2007

The spindle-shaped β-FeOOH/polyacrylonitrile-amidoxime (PAN-amidhydrazone)/silver composite particles with a stable core-shell structure were successfully fabricated in the mixed solvent of dimethylformamide (DMF) and methanol using a seed-mediated growth technique, where metal silver nanoparticles tethered on β-FeOOH served as the nucleation sites for the growth of the silver nanoshell overlayer. The closed silver shell was finally formed after the seed catalyzed growing process repeated several cycles. The results of transmission electron microscopy (TEM) showed that the composite nanoparticles were spindle-shape. The resulting nanoparticles showed good stability under various conditions.
Estimation of a Preference-Based Index from a Condition-Specific Measure: The King's Health Questionnaire
Authors: Brazier John , Czoski-Murray Carolyn , Roberts Jennifer , Brown Martin , Symonds Tara , Kelleher Con
Published: July 2007

Background. Generic preference-based measures of health may not adequately cover the impact of some conditions. There is therefore increasing interest in developing condition-specific preference-based measures. Objectives. The purpose of this study was to estimate a preference-based measure from a condition-specific measure of health for urinary incontinence, the 21-item King's Health Questionnaire, for use in economic evaluation. Methods. The King's Health Questionnaire (KHQ) was revised into a 5-dimensional health state classification amenable to valuation using items selected using psychometric evidence. Forty-nine states were valued using standard gamble by a representative sample of patients with urinary incontinence attending UK hospital outpatient clinics. Each respondent was asked to value 9 health states. Models have been estimated for predicting health state valuations for all 1024 states defined by the KHQ classification. The modeling had to cope with the clustering of data by respondent and its skewed distribution. Results. In total, 110 usable interviews were obtained from 169 patients approached to participate in the study. These responders generated 959 health state valuations. Mean health state values ranged from 0.77 to 0.98. Models were estimated using mean health state values and random effects models of individual-level health state values. These models generated robust estimates of the `main effects,` and in general, the results support the ordinality of the KHQ health state classification. There were problems modeling interaction effects, and a number of alternatives were explored. Conclusion. The recommended model for estimating a preference-based measure from the condition-specific KHQ is presented.
Cost-Effectiveness Analysis Using Data from Multinational Trials: The Use of Bivariate Hierarchical Modeling
Authors: Manca Andrea , Lambert Paul C. , Sculpher Mark , Rice Nigel
Published: July 2007

Health care cost-effectiveness analysis (CEA) often uses individual patient data (IPD) from multinational randomized controlled trials. Although designed to account for between-patient sampling variability in the clinical and economic data, standard analytical approaches to CEA ignore the presence of between-location variability in the study results. This is a restrictive limitation given that countries often differ in factors that could affect the results of CEAs, such as the availability of health care resources, their unit costs, clinical practice, and patient case mix. The authors advocate the use of Bayesian bivariate hierarchical modeling to analyze multinational cost-effectiveness data. This analytical framework explicitly recognizes that patient-level costs and outcomes are nested within countries. Using real-life data, the authors illustrate how the proposed methods can be applied to obtain (a) more appropriate estimates of overall cost-effectiveness and associated measure of sampling uncertainty compared to standard CEA and (b) country-specific cost-effectiveness estimates that can be used to assess the between-location variability of the study results while controlling for differences in country-specific and patientspecific characteristics. It is demonstrated that results from standard CEA using IPD from multinational trials display a large degree of variability across the 17 countries included in the analysis, producing potentially misleading results. In contrast, ``shrinkage estimates'' obtained from the modeling approach proposed here facilitate the appropriate quantification of country-specific cost-effectiveness estimates while weighting the results based on the level of information available within each country. The authors suggest that the methods presented here represent a general framework for the analysis of economic data collected from different locations.
A Cautionary Note on Data Sources for Evidence-Based Clinical Decisions: Warfarin and Stroke Prevention
Authors: Thomson Richard , Eccles Martin , Wood Ruth , Chinn David J.
Published: July 2007

Background. Stroke risk in nonvalvular atrial fibrillation can be reduced by warfarin or aspirin; the choice of therapy requires the assessment of risks and benefits. The authors compared methods of risk assessment and their implications for risk communication and treatment. Methods. Stroke risk was compared in 193 patients with atrial fibrillation using the Framingham equation; an atrial fibrillation—specific Framingham equation; the Congestive heart failure, Hypertension, Age, Diabetes and Stroke (CHADS2) score; the Stroke Prevention and Atrial Fibrillation (SPAF) scheme; and the Scottish Intercollegiate Guidelines Network (SIGN) guidelines. Treatment guidance from SIGN, a simple prediction rule, and a decision analytical approach was compared. In the latter, patients were classified as risk too low to benefit from warfarin if the risk of cerebral bleeding on warfarin approximated to, or exceeded, thromboembolic stroke risk reduction. Results. Framingham equations gave lower stroke risks overall than SIGN or SPAF. CHADS2 was intermediate. Using SIGN, warfarin would be given to all 103 patients without a history of stroke/transient ischemic attack and for whom warfarin was not contraindicated but only to 73 patients using the simple prediction rule and 48 patients using the decision analysis. Conclusion. Community-based cohorts give lower stroke risk estimates than CHADS2; both give lower estimates than schemes from control groups from randomized controlled trials. Using community-derived risks would lead to fewer patients being treated with warfarin than guidance derived from randomized controlled trial controls, which may lead to many low-risk patients being treated with high-risk therapy. This raises the debate about appropriate sources of data for risk assessment to support risk communication and effective clinical decisions.
Does Concordance with Guideline Triage Recommendations Affect Clinical Care of Patients with Possible Acute Coronary Syndrome?
Authors: Katz David A. , Dawson Jeffrey , Beshansky Joni R. , Rahko Peter S. , Aufderheide Tom P. , Bogner Mark , Tighouart Hocine , Selker Harry P.
Published: July 2007

Background. The Agency for Health Care Policy and Research (AHCPR) Unstable Angina Practice Guideline recommends outpatient management for patients at low risk and admission to a monitored bed for patients at intermediate-high risk of adverse short-term outcomes, but the clinical consequences of adhering to these recommendations are unclear. Methods. This analysis included 7466 adults who presented to the emergency department (ED) with symptoms of possible acute coronary syndrome (ACS) and who participated in 3 prospective clinical effectiveness trials during the period 1993 to 2001. The authors used logistic regression to assess the impact of concordance with guideline triage recommendations on subsequent diagnostic testing, follow-up care, and 30-day mortality and applied propensity score methods to adjust for selection bias. Results. Among low-risk patients (n = 1099), ED discharge was not associated with higher mortality and did not increase the need for emergency care or hospitalization during follow-up (adjusted odds ratio [OR] = 1.0, 95% confidence interval [CI] = 0.63—1.6 for ED revisits); however, 1.7% of discharged low-risk patients had confirmed ACS. Among intermediate- to high-risk patients (n = 6367), admission to a monitored bed was not associated with reduction in 30-day mortality but significantly reduced the need for follow-up ED care (adjusted OR = 0.81, 95% CI = 0.69—0.96). Conclusions. This analysis supports the practice of discharging low-risk ED patients with symptoms of possible ACS but highlights the need to arrange timely follow-up (or to perform additional risk stratification in the ED prior to discharge). It also confirms the benefit of admitting ED patients with intermediate- to high-risk characteristics to a monitored bed.
Measuring Numeracy without a Math Test: Development of the Subjective Numeracy Scale
Authors: Fagerlin Angela , Zikmund-Fisher Brian J. , Ubel Peter A. , Jankovic Aleksandra , Derry Holly A. , Smith Dylan M.
Published: July 2007

Background. Basic numeracy skills are necessary before patients can understand the risks of medical treatments. Previous research has used objective measures, similar to mathematics tests, to evaluate numeracy. Objectives. To design a subjective measure (i.e., self-assessment) of quantitative ability that distinguishes low- and high-numerate individuals yet is less aversive, quicker to administer, and more useable for telephone and Internet surveys than existing numeracy measures. Research Design. Paper-and-pencil questionnaires. Subjects. The general public (N = 703) surveyed at 2 hospitals. Measures. Forty-nine subjective numeracy questions were compared to measures of objective numeracy. Results. An 8-item measure, the Subjective Numeracy Scale (SNS), was developed through several rounds of testing. Four items measure people's beliefs about their skill in performing various mathematical operations, and 4 measure people's preferences regarding the presentation of numerical information. The SNS was significantly correlated with Lipkus and others' objective numeracy scale (correlations: 0.63—0.68) yet was completed in less time (24 s/item v. 31 s/item, P < 0.05) and was perceived as less stressful (1.62 v. 2.69, P < 0.01) and less frustrating (1.92 v. 2.88, P < 0.01). Fifty percent of participants who completed the SNS volunteered to participate in another study, whereas only 8% of those who completed the Lipkus and others scale similarly volunteered (odds ratio = 11.00, 95% confidence interval = 2.14—56.65). Conclusions. The SNS correlates well with mathematical test measures of objective numeracy but can be administered in less time and with less burden. In addition, it is much more likely to leave participants willing to participate in additional research and shows much lower rates of missing or incomplete data.
Data Structures for Efficient Dynamic Processing in 3-D
Authors: Lalonde Jean-François , Vandapel Nicolas , Hebert Martial
Published: July 2007

This paper considers the problem of the dynamic processing of large amounts of sparse three-dimensional data. It is assumed that computations are performed in a neighborhood defined around each point in order to retrieve local properties. This general kind of processing can be applied to a wide variety of problems. A new, efficient data structure and corresponding algorithms are proposed that significantly improve the speed of the range search operation and that are suitable for on-line operation where data is accumulated dynamically. The method relies on taking advantage of overlapping neighborhoods and the reuse of previously computed data as the algorithm scans each data point. To demonstrate the dynamic capabilities of the data structure, data obtained from a laser radar mounted on a ground mobile robot operating in complex, outdoor environments is used. It is shown that this approach considerably improves the speed of an established 3-D perception processing algorithm.
The Relationship between the Outcome of Studies of Autologous Chondrocyte Implantation and the Presence of Commercial Funding
Authors: Lubowitz James H. , Appleby David , Centeno Joseph M. , Woolf Shane K. , Reid John B.
Published: July 2007

Background

Autologous chondrocyte implantation (ACI) is an expensive treatment option for focal cartilage defects, and commercial funding of research is associated with a study reaching a positive conclusion. The purpose of this analysis is to compare outcomes (and levels of evidence) between published ACI outcome studies that were commercially funded and studies that were not commercially funded.

Hypothesis

Commercially funded ACI literature could be commercially biased.

Study Design

Comparative meta-analysis.

Methods

MEDLINE was searched for human, knee, ACI, nonmembrane, English language, and clinical outcome studies. Studies were evaluated with regard to funding status (commercially funded or not commercially funded), outcomes, and levels of evidence. Outcomes and levels of evidence were evaluated and compared for commercially funded studies versus those that were not commercially funded.

Results

Twenty-three studies were included; 16 (70%) were commercially funded. Pooled clinical outcome measures data were not significantly different (Lysholm, Modified Cincinnati, patient-reported Cincinnati, Tegner, pain Visual Analog Scale) when comparing commercially funded studies with those that were not commercially funded. However, distribution of levels of evidence was significantly lower (P = .045) for commercially funded studies.

Conclusion

Reassuringly, commercial funding of ACI studies did not result in a difference in published clinical outcomes versus those that were not commercially funded. However, the lower levels of evidence of commercially funded studies suggests that commercially funded ACI studies may be of less value to surgeons desiring to practice evidence-based medicine, and, in the future, commercial entities funding medical research could selectively fund studies of the highest levels of evidence.
Measuring Growth and Decline in Visual-Motor Processes With the Bender-Gestalt Second Edition
Authors: Decker Scott L.
Published: July 2007

The purpose of this study is to develop a change-sensitive scale for evaluating developmental change in visual-motor ability across the life span. A partial-credit item-response model is used to estimate theta values for each age group between 4 and 90 using the Bender-Gestalt II standardization sample ( N = 4,000). Results from this study suggest that visual-motor ability has a rapid maturation lasting into middle adolescence, steadily decreases through adulthood, and rapidly declines in later age ranges. These results provide evidence against previous research conclusions that suggested visual-motor ability development ends in late childhood and remains steady across the life span. A case study is provided to demonstrate the practical use of the change-sensitive scale in monitor intervention outcomes.
Initial Reliability and Validity of the Perceived Social Competence Scale
Authors: Anderson-Butcher Dawn , Iachini Aidyn L. , Amorose Anthony J.
Published: July 2007

Objective: This study describes the development and validation of a perceived social competence scale that social workers can easily use to assess children's and youth's social competence. Method: Exploratory and confirmatory factor analyses were conducted on a calibration and a cross-validation sample of youth. Predictive validity was also established. Results: A four-item measure, labeled the Perceived Social Competence Scale (PSCS) , demonstrated acceptable internal consistency and factorial validity in samples of children and youth participating in youth development programs. Additionally, tests for gender invariance indicated that the PSCS worked equally well for males and females. The PSCS also demonstrated predictive validity, correlating positively with perceived belonging. Conclusion: Support was found for the PSCS as an empirically sound tool to assess children and youth's perceptions of social competence.
Dynamic Organization of the Emotional Brain: Responsivity, Stability, and Instability
Authors: Williams Leanne M. , Gordon Evian
Published: July 2007

Models of emotion processing have commonly been formulated as dichotomies such as approach versus avoidance. These models and associated research on evolutionary adaptation, awareness, motivational arousal, and cortical—subcortical brain systems are reviewed. A continuum model of emotional-significance processing is proposed to integrate current dichotomies and reflect the highly interconnected nature of brain systems. This model highlights a spectrum from “mismatches,” signifying potential danger, to “matches,” signifying safety and the expectation of reward. Subcortical—cortical interactions and autonomic arousal modulation support mismatch and match processing across a temporal continuum from milliseconds (in which processing is automatic and arguably nonconscious) to tenths of a second (in which responses are facilitated and contextual evaluation commences) to minutes and hours (when memory consolidation and neural plasticity occur). Variations at distinct points along this continuum, with contributions from constitutional and genetic factors, may contribute to individual differences in emotional stability and instability in neuropsychiatric disorders. NEUROSCIENTIST 13(4): 349—370, 2007. DOI: 10.1177/1073858407303429
Remyelination of the Central Nervous System: A Valuable Contribution from the Periphery
Authors: Zujovic Violetta , Bachelin Corinne , Baron-Van Evercooren Anne
Published: July 2007

The loss of myelin, a major element involved in the saltatory conduction of the electrical impulse of the nervous system, is a major target of current research. Serious long-term disabilities are observed in patients with demyelinating disease of the central nervous system, such as multiple sclerosis. New therapeutic strategies aimed at overcoming myelin damage and axonal loss focus on the repair potential of myelin-forming cells. This review examines the use of peripheral myelin-forming cells, the Schwann cells, to promote myelin repair. NEUROSCIENTIST 13(4):383—391, 2007. DOI: 10.1177/1073858407300762
Occupational Exposure to HIV Among Health Care Providers: A Qualitative Study in Yunnan, China
Authors: Chunqing Lin  , Li Li  , Zunyou Wu  , Sheng Wu  , Manhong Jia
Published: July 2007

With the HIV/AIDS epidemic spreading, health care providers (HCPs) in China are facing a growing risk of occupational exposure to and infection with HIV. There is a need to describe occupational exposure cases and compliance with postexposure prophylaxis (PEP) guidelines among HCPs. Qualitative in-depth interviews were conducted with 33 HCPs in Yunnan Province, China. Information about occupational exposures the HCPs and their co-workers experienced was collected and analyzed using ATLAS.ti. Most occupational exposure accidents happened during emergencies, when HCPs did not have time to consider self-protection. Exposure to HIV caused exposed HCPs severe adverse psychological pressure, such as stress and anxiety. Compliance with PEP guidelines among participants was poor; barriers to better compliance were identified. This study underscored the importance of institutional support in promoting compliance with PEP guidelines among exposed providers. Further training and emphasis on universal precautions and PEP guidelines may reduce the risk of occupational infections.
Riga-Fede-Like Disease in an AIDS Patient
Authors: Santos Cunha Vanessa , Rocha Zanol Jorge David , Sprinz Eduardo
Published: July 2007

Riga-Fede disease is a benign and ulcerative process that occurs as a result of repetitive trauma of the oral mucosal surfaces by the teeth. The authors describe here a case of a 40-year-old man in rescue therapy for advanced AIDS with a 2-month history of an ulcerated area on the dorsal surface of his tongue, which was histopathologically consistent with Riga-Fede disease. This case report is unique because it is the first time that this lesion has been reported in an AIDS patient, and Riga-Fede disease should be included in the differential diagnosis of a tongue ulcer in these populations.
Protease-activated receptor-4 inhibition protects from multiorgan failure in a murine model of systemic inflammation
Authors: Slofstra Sjoukje H. , Bijlsma Maarten F. , Groot Angelique P. , Reitsma Pieter H. , Lindhout Theo , ten Cate Hugo , Spek C. Arnold
Published: July 2007

Coagulation proteases may act as cell signaling molecules via protease-activated receptor (PAR) cleavage, subsequently affecting cellular and inflammatory responses. Activation of PARs in the setting of systemic inflammation and disseminated intravascular coagulation (DIC) might thus exacerbate the inflammatory response contributing to tissue and organ damage. To investigate the role of PAR-4 in these processes, we subjected mice to a model of systemic inflammation and DIC (Shwartzman reaction) in the absence or presence of a cell-penetrating pepducin antagonist of PAR-4 (P4pal-10). P4pal-10 dose-dependently diminished the severity of endotoxemia and preserved liver, kidney, as well as lung function. Moreover, systemic inflammation and local (neutrophilic) inflammatory responses were attenuated. In vitro migration assays and P4pal-10 treatment in neutropenic mice suggest an essential role for neutrophils in PAR-4–mediated pathology. P4pal-10 treatment of thrombocytopenic mice excluded the involvement of platelets in this phenomenon. These results uncover an important role for PAR-4 in the Shwartzman reaction and suggest that inhibition of PAR-4 signaling in neutrophils could be protective in systemic inflammation and DIC.
Anti-inflammatory effects of Lactobacillus casei BL23 producing or not a manganese-dependant catalase on DSS-induced colitis in mice
Authors: Rochat Tatiana , Bermúdez-Humarán Luis , Gratadoux Jean-Jacques , Fourage Christel , Hoebler Christine , Corthier Gérard , Langella Philippe
Published: July 2007

Background

Human immune cells generate large amounts of reactive oxygen species (ROS) throughout the respiratory burst that occurs during inflammation. In inflammatory bowel diseases, a sustained and abnormal activation of the immune system results in oxidative stress in the digestive tract and in a loss of intestinal homeostasis. We previously showed that the heterologous production of the Lactobacillus plantarum ATCC14431 manganese-dependant catalase (MnKat) in Lb. casei BL23 successfully enhances its survival when exposed to oxidative stress. In this study, we evaluated the preventive effects of this antioxidative Lb. casei strain in a murine model of dextran sodium sulfate (DSS)-induced moderate colitis.

Results

Either Lb. casei BL23 MnKat- or MnKat+ was administered daily to mice treated with DSS for 10 days. In contrast to control mice treated with PBS for which DSS induced bleeding diarrhea and mucosal lesions, mice treated with both Lb. casei strains presented a significant (p < 0.05) reduction of caecal and colonic inflammatory scores.

Conclusion

No contribution of MnKat to the protective effect from epithelial damage has been observed in the tested conditions. In contrast, these results confirm the high interest of Lb. casei as an anti-inflammatory probiotic strain.