bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical simulation of diffusion‐controlled nucleation and growth of porphyroblasts
Authors: KETCHAM R. A. , CARLSON W. D. 
Published: May 2012

AbstractThis article presents the conceptual basis for a new numerical model of diffusion‐controlled nucleation and growth of porphyroblasts, describes its implementation, and illustrates the range of crystallization behaviours encompassed by it. The model differs from previous efforts principally in its ability to track explicitly the evolution in time and space of the chemical affinity for reaction in the intergranular medium, which provides a more accurate characterization of nucleation suppression in the vicinity of pre‐existing crystals and of growth suppression due to competition for nutrients among neighbouring crystals. Critical new features of these numerical simulations include: maintenance of local equilibrium for fluid in contact with reactants or products; persistence of reactants until they are eliminated by dissolution due to reaction progress and local diffusive flux; nucleation rates that vary as the local reaction affinity evolves; complex initial distributions of reactants if desired; and the flexibility to encompass any porphyroblast‐forming reaction for which changes in free energy as a function of time and temperature are specified. Model results reveal that radial growth rates remain proportional to the square‐root of time in diffusion systems buffered by persistent reactants; they document the interchangeable effects of diffusivity, porosity, and solubility on material fluxes and thus growth rates; and they illustrate the offsetting textural effects of rates of diffusion, nucleation, and heating. The initial distribution of reactants is found to exert a first‐order effect on crystal size distributions, confirming their limited utility for diagnosing crystallization mechanisms. These numerical simulations yield novel and rigorous confirmation of the textural effects of nucleation‐site saturation and variation in interconnected porosity, and reproduce with high fidelity much of the textural and chemical information gathered from natural specimens.
The Association Between Geriatric Syndromes and Survival
Authors: Kane Robert L. , Shamliyan Tatyana , Talley Kristine , Pacala James 
Published: May 2012

ObjectivesTo ascertain the effect on survival of eight common geriatric syndromes (multiple comorbidities, cognitive impairment, frailty, disability, sarcopenia, malnutrition, homeostenosis, and chronic inflammation), identified by an expert panel of academic geriatricians.DesignA systematic literature review sought studies from a variety of sources to compare survival and life expectancy of individuals with geriatric syndromes with those of the general population.SettingStudies used reflected the general population.ParticipantsCommunity‐dwelling persons aged 65 and older.MeasurementsEight geriatric syndromes (multiple definitions) and survival.ResultsTwo thousand three hundred seventy‐four publications were retrieved, and 509 publications of 123 studies were included. Seven geriatric syndromes (multiple comorbidities, cognitive impairment, frailty, disability, malnutrition, impaired homeostasis, and chronic inflammation) were associated with poor survival. In each case, the prevalence of a syndrome was negatively associated with mortality. Malnutrition and impaired homeostasis exerted twice the influence of factors such as multiple comorbidities and frailty. From age 65 to 74, only those who are very ill or frail (e.g., impaired homeostasis, low body mass index, or advanced dementia) have a higher risk of mortality than average older adults. In the old‐old, particularly aged 90 and older, the added value of predicting survival beyond 1 year is minimal.ConclusionGeriatric syndrome information is helpful to understanding survival for younger old persons but provides little information about survival for the very old. Complex survival models add comparatively little benefit to more simply measured and calculated models.
Use of Pelvic Flexure Biopsy Scores to Predict Short‐Term Survival after Large Colon Volvulus
Authors: Levi Ohad , Affolter Verena K. , Benak Jaromir , Kass Philip H. , Le Jeune Sarah S. 
Published: May 2012

ObjectiveTo (1) determine if histologic scores of pelvic flexure biopsies can predict short‐term survival in horses with large colon volvulus (LCV) and (2) identify clinical variables predictive of short‐term survival.Study DesignCase series.AnimalsHorses (n = 28) with LCV (≥360°).MethodsMedical records (January 2000–February 2008) of 28 horses were reviewed and clinical data recorded. Pelvic flexure biopsies were reviewed by 2 board‐certified veterinary pathologists, unaware of clinical history and outcome, using 2 scoring systems. Exact logistic regression analysis was used to determine the relationship between histopathology scores (tissue viability), clinical data, and short‐term survival (hospital discharge).ResultsTwenty‐four horses (86%) survived to hospital discharge. Using a similar cutoff, neither scoring system was capable of predicting short‐term survival. One scoring system failed to correctly predict clinical outcome in 5/25 horses (20%) and the other failed in 6/28 horses (22.4%). Heart rate (at admission and 24 hours after surgery) and packed cell volume 24 hours after surgery were significantly associated with short‐term survival.ConclusionHistopathologic evaluation of pelvic flexure biopsies did not accurately predict short‐term survival in a significant proportion of horses with LCV in this study.
Reversible, Complete Atrioventricular Block Caused by Primary Cardiac Lymphoma in a Nonimmunocompromised Patient
Authors: CRISEL RYAN K. , KNIGHT BRADLEY P. , KIM SUSAN S. 
Published: May 2012

PCL in a Nonimmunocompromised PatientPrimary cardiac lymphoma (PCL) is a rare entity that commonly presents as a heart rhythm disorder. We describe a previously healthy, immunocompetent patient presenting with complete atrioventricular block (AVB). The patient was found to have a cardiac mass on magnetic resonance imaging and underwent percutaneous biopsy eventually diagnosing PCL. After pacemaker implantation, the patient's tumor responded rapidly to chemotherapy and the AVB completely resolved. In otherwise healthy patients presenting with AV block, cardiac tumor should be considered. Additionally, if PCL is diagnosed and the patient is clinically stable with AVB, it may be reasonable to delay pacemaker implantation until the clinical response to chemotherapy is evaluated. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1386‐1389, December 2012)
Effects of Enthalpy‐Enhancing Gas on Ionic Conductivity of Atmospheric Plasma‐Sprayed 3.9YSZ Electrolyte for 20–45 μm Particles
Authors: Wu Hann‐Pyng , Fung Kuan‐Zong 
Published: May 2012

Enthalpy‐enhancing gas is used to optimize the ionic conductivity of atmospheric plasma‐sprayed 3.9 mol% yttria‐stabilized zirconia (3.9YSZ) electrolyte. In the experiment, three hydrogen gas flow rates were used to control the plasma energy. The size of the 3.9YSZ feedstock powder was sieved to be in the range of 20–45 μm. When the hydrogen gas flow rate increased, the sprayed surfaces became rougher. Nevertheless, the lowest apparent porosity, the highest bulk density, and the hardest electrolyte were obtained at the hydrogen gas flow rate at 7 L/min. A 3.9YSZ electrolyte with an ionic conductivity of 1480 μ (Ω cm)‐1 was obtained at 800°C, when the hydrogen gas flow rate was at 12 L/min. It was controlled by the grain‐boundary conductivity, which was closely related to the lowest migration energy, the highest density of the columnar grains, and the closest bonding between lamellar layers. The increase in the hydrogen gas could diminish the amount of the migration energy and increase the grain‐boundary conductivity. On the other hand, a larger cubic lattice constant and a less amount of the monoclinic phase in the as‐sprayed electrolyte helped obtain greater intragrain conductivity.
Expression of selected genes in preterm premature rupture of fetal membranes
Authors: KUĆ PAWEŁ , LAUDAŃSKI PIOTR , KOWALCZUK OKSANA , CHYCZEWSKI LECH , LAUDAŃSKI TADEUSZ 
Published: May 2012

Abstract Objective. To analyse the expression of 15 genes encoding receptors and enzymes associated with the molecular mechanism of the tocolytic drugs atosiban (oxytocin receptor antagonist), nifedipine (calcium channel blocker) and celecoxib (selective cyclo‐oxygenase‐2 inhibitor) in preterm labor patients with premature rupture of fetal membranes in relation to symptoms of intrauterine infection and preterm labor risk factors. Design. Experimental molecular study. Setting. Tertiary obstetric care center. Sample. Myometrial samples were obtained during cesarean sections from 35 patients who delivered preterm with unverified symptoms of intrauterine infection, 35 patients who delivered preterm without symptoms of intrauterine infection and 90 women who delivered at term. Methods. The Micro Fluidic Profiling Card analytic system was used to evaluate mRNA expression of the genes of interest. Main outcome measures. The relative quantification values for mRNA expression. Results. The median oxytocin receptor and cyclo‐oxygenase‐2 mRNA expression in preterm patients with clinical symptoms of intrauterine infection was significantly higher than in preterm patients without symptoms. The median mRNA expression of β1, β3 and β4 subunits of the L‐type calcium channel and prostaglandin E2 receptor was significantly higher in preterm patients compared with term patients. Conclusions. The mRNA expression of hormones, enzymes and their receptors associated with tocolytic actions can differ in various clinical conditions. The expression of these genes is regulated at different levels and can be modified by inflammatory factors, which affect their functions.
Establishing a national program for fetoscopic guided laser occlusion for twin‐to‐twin transfusion syndrome in Sweden
Authors: EK SVERKER , KUBLICKAS MARIUS , BUI THE‐HUNG , DELLGREN ANNIKA , PAPADOGIANNAKIS NIKOS , TIBLAD ELEONOR , WÅGSTRÖM ELLE , WESTGREN MAGNUS 
Published: May 2012

Abstract Objective. To describe the establishment of the fetoscopic guided laser occlusion (FLOC) technique for treatment of twin‐to‐twin transfusion syndrome (TTTS) and the initial results in a Swedish national center. Design. Retrospective, descriptive study. Setting. Tertiary level university hospital. Population. All referred and treated cases suffering significant TTTS. Methods. The present study includes all cases of FLOC for TTTS at the Center of Fetal Medicine at Karolinska University Hospital, Stockholm, Sweden from October 2001 until December 2009. Patients were referred from all over Sweden and a few from other Nordic countries. The patients were evaluated with ultrasound examination between gestational ages of 18 and 26 weeks. Data from patients were extracted from our electronic medical record system and, in addition, families were contacted and medical records requested from referring hospitals. Main outcome measures. Pregnancies with one or more surviving infants after FLOC treatment categorized according to stage of TTTS. Results. In 75% of pregnancies, one or more infant was born alive. At stage I, both infants survived in one pregnancy and one survived in the second. There was no significant difference between cases at stage II or III, i.e. 73 vs. 78% of pregnancies resulted in one or more surviving infant. At stage IV, 66% of pregnancies ended with one or more surviving infant. Conclusions. Treatment of TTTS is feasible in a rather small country like Sweden, with comparable results to other centers. There are strong arguments for centralization and further improvement of this kind of highly specialized treatment.
Short‐term complications of implant‐supported and combined tooth‐implant‐supported fixed dental prostheses
Authors: Rammelsberg Peter , Schwarz Stefanie , Schroeder Christin , Bermejo Justo L. , Gabbert Olaf 
Published: May 2012

AbstractObjectiveThe objective of this clinical study was to evaluate survival and incidence of complications for metal‐ceramic and all‐ceramic implant‐supported fixed dental prostheses (FDPs) and tooth‐implant‐supported FDPs.Material and methodsOne‐hundred and sixty‐six FDPs placed in 132 patients from a prospective study were selected for this retrospective analysis. Included were 91 conventional implant‐supported FDPs with implant support on both extremities, 27 implant‐supported cantilever FDPs, and 48 tooth‐implant‐supported FDPs. All restorations were veneered with ceramic. Twenty‐six FDPs had a zirconia framework and 140 had a metal framework. Kaplan–Meier analysis was performed to estimate FDP success defined as complication‐free survival and the Cox regression model was used to isolate risk factors for the most frequent complications.ResultsWithin a median follow‐up of 1 year and 2 months, three failures were caused by a failed implant (n = 2) and by extended chipping of the veneer (n = 1). In contrast with this low incidence of failure was a high incidence of complications including chipping (n = 29), loss of retention (n = 35), and abutment fractures (n = 2). Multivariate survival analysis revealed a significantly greater incidence of chipping for males and a tendency to increased incidence of chipping for zirconia‐based FDPs. The incidence of loss of retention tended to be less for tooth‐implant‐supported FDPs, for which semi‐permanent cement was the only significant risk factor, with a hazard ratio of almost 5.ConclusionsAs chipping of the ceramic veneer was the most frequent complication leading to substantial aftercare, improvements of ceramic veneers are desirable for zirconia‐based and metal‐based FDPs.
Anti‐infective therapy of peri‐implantitis with adjunctive local drug delivery or photodynamic therapy: six‐month outcomes of a prospective randomized clinical trial
Authors: Schär Dorothee , Ramseier Christoph A. , Eick Sigrun , Arweiler Nicole B. , Sculean Anton , Salvi Giovanni E. 
Published: May 2012

AbstractObjectiveTo compare the adjunctive clinical effects in the non‐surgical treatment of peri‐implantitis with either local drug delivery (LDD) or photodynamic therapy (PDT).Material and methodsForty subjects with initial peri‐implantitis, i.e. pocket probing depths (PPD) 4–6 mm with concomitant bleeding on probing (BoP) and marginal bone loss ranging from 0.5 to 2 mm between delivery of the reconstruction and pre‐screening appointment were randomly assigned to two treatment groups. All implants underwent mechanical debridement with titanium curettes, followed by a glycine‐based powder airpolishing. Implants in the test group (n = 20) received adjunctive PDT, whereas minocycline microspheres were locally delivered into the peri‐implant pockets of control implants (n = 20). At sites with residual BoP, treatment was repeated after 3 and 6 months. The primary outcome variable was the change in the number of sites with BoP. Secondary outcome variables were changes in PPD, in clinical attachment level (CAL), and in mucosal recession (REC).ResultsAfter 3 months, implants of both groups yielded a statistically significant reduction (P < 0.0001) in the number of BoP‐positive sites compared with baseline (LDD: from 4.41 ± 1.47 to 2.20 ± 1.28, PDT: from 4.03 ± 1.66 to 2.26 ± 1.28). After 6 months, complete resolution of mucosal inflammation was obtained in 15% of the implants in the control group and in 30% of the implants in the test group (P = 0.16). After 3 months, changes in PPD, REC, and modified Plaque Index (mPlI) were statistically significantly different from baseline (P < 0.05). No statistically significant changes (P > 0.05) occurred between 3 and 6 months. CAL measurements did not yield statistically significant changes (P > 0.05) in both groups during the 6‐month observation time. Between‐group comparisons revealed no statistically significant differences (P > 0.05) at baseline, 3 and 6 months with the exception of the mPlI after 6 months.ConclusionsIn cases of initial peri‐implantitis, non‐surgical mechanical debridement with adjunctive use of PDT is equally effective in the reduction of mucosal inflammation as with the adjunctive use of minocycline microspheres up to 6 months. Adjunctive PDT may represent an alternative treatment modality in the non‐surgical management of initial peri‐implantitis. Complete resolution of inflammation, however, was not routinely achieved with either of the adjunctive therapies.
A quantification of occupational skin exposures and the use of protective gloves among hairdressers in Denmark
Authors: Lysdal Susan Hovmand , Johansen Jeanne Duus , Flyvholm Mari‐Ann , Søsted Heidi 
Published: May 2012

Background. Occupational hand eczema is common in hairdressers, owing to excessive exposure to wet work and hairdressing chemicals.Objectives. To quantify occupational skin exposure and the use of protective gloves among hairdressers in Denmark.Methods. A register‐based study was conducted comprising all graduates from hairdressing vocational schools from 1985 to 2007 (n = 7840). The participants received a self‐administered postal questionnaire in May 2009, including questions on hairdressing tasks performed in the past week at work and the extent of glove use. A response rate of 67.9% (n = 5324) was obtained.Results. Of the respondents, 55.7% still worked as hairdressers, and they formed the basis of this study. Daily wet work was excessive; 86.6% had wet hands for ≥2 hr, and 54% for ≥ 4 hr. Glove use was fairly frequent for full head hair colouring and bleaching procedures (93–97.7%), but less frequent for highlighting/lowlighting procedures (49.7–60.5%) and permanent waving (28.3%). Gloves were rarely worn during hair washing (10%), although this was more frequently the case after hair colouring procedures (48.9%).Conclusions. Occupational skin exposure was excessive among hairdressers; the extent of wet work and chemical treatments was high, and glove use was inconsistent, especially for certain hair colouring procedures and wet work tasks.
Using multiple measures to evaluate a dental faculty development program
Authors: McAndrew M. , Pierre G. C. 
Published: May 2012

AbstractIntroductionThe formal preparation of dental professionals for teaching is increasingly seen as essential to enhance teacher effectiveness and student learning and to promote curricular initiatives. As a result, many dental schools have implemented a variety of faculty development programming. There is a body of literature that describes these programmes, but there is limited rigorous evaluation of them. The use of multiple measures of evaluation helps to compensate for potential inadequacies of individual methods. Analyses with multiple measures provide a more comprehensive view of whether a programme is achieving its learning outcomes.Materials and methodsA dental faculty development programme, Class Advanced Clinical Teaching Scholars (ACTS), at New York University College of Dentistry (NYUCD) was evaluated with four different measures: pre‐ and post‐programme tests of participants' level of relevant pedagogical knowledge, pre‐ and post‐programme objective structured teaching examinations (OSTEs), pre‐ and post‐programme self‐assessments of teaching abilities and post‐programme participant satisfaction surveys. Two of the measures used a comparison group of faculty.ResultsResults revealed that the Class ACTS participants significantly improved their knowledge; observed teaching performance in most teaching domains tested showed significant improvement; there was no significant change in self‐assessed teaching abilities after participation; and the course was viewed positively by the participants.ConclusionClass ACTS, an advanced dental faculty development course, has been successfully implemented and evaluated with the use of multiple measures.
The influence of trees on nutrients, water, light availability and understorey vegetation in an arid environment
Authors: Abdallah F. , Chaieb M. 
Published: May 2012

AbstractQuestionsDo Acacia tortilis trees facilitate herbaceous species development under arid conditions? Do tree–herb interactions change with water stress and grazing intensity?LocationNational Park in a Tunisian arid area (34°39′N, 9°48′E).MethodsSoil water content, soil nutrient concentration, light intensity and microclimatic data were collected under the canopy and in open areas to evaluate the relative roles of A. tortilis (Forssk.) subsp. raddiana (Savi) trees in structuring vegetation composition and diversity patterns in a arid pseudo‐savanna. Data were collected inside and outside Bou Hedma National Park, both during a dry and a wet year.ResultsIn both unprotected and protected areas, the influence of the tree canopy on the herbaceous strata can be considered as positive, even though it is more significant inside the park. This positive interaction increased with higher abiotic stress conditions and decreased with grazing intensification. Soil nutrients (organic matter, total N, extractable P) and moisture availability was greater under tree canopies than in the open. Species composition of the herb layer also differed between Acacia trees and open areas. Some palatable species were found under trees, and were replaced by less desirable species in the open. Microclimate measurements showed significant differences in light intensity reaching the soil, mean air temperatures and relative humidity.ConclusionsThese results suggest that the optimal association of climate factors under the canopy would combine with a high soil fertility mediated by litter decomposition to increase plant cover under tree canopies.
Disc scalelengths out to redshift 5.8
Authors: Fathi K. , Gatchell M. , Hatziminaoglou E. , Epinat B. 
Published: May 2012

ABSTRACT
We compute the exponential disc scalelength for 686 disc galaxies with spectroscopic redshifts out to redshift 5.8 based on Hubble Space Telescope archival data. We compare the results with our previous measurements based on 30 000 nearby galaxies from the Sloan Digital Sky Survey. Our results confirm the presence of a dominating exponential component in galaxies out to this redshift. At the highest redshifts, the disc scalelength for the brightest galaxies with absolute magnitude between −24 and −22 is up to a factor of 8 smaller compared to that in the local Universe. This observed scalelength decrease is significantly greater than the value predicted by a cosmological picture in which baryonic disc scalelength scales with the virial radius of the dark matter halo.