bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation in a Disaster Drill: Comparison of High‐fidelity Simulators versus Trained Actors
Authors: Gillett Brian , Peckler Brad , Sinert Richard , Onkst Cherie , Nabors Spencer , Issley Steven , Maguire Christopher , Galwankarm Sagar , Arquilla Bonnie
Published: August 2008

Objectives:  High‐fidelity patient simulation provides lifelike medical scenarios with real‐time stressors. Mass casualty drills must construct a realistic incident in which providers care for multiple injured patients while simultaneously coping with numerous stressors designed to tax an institution’s resources. This study compared the value of high‐fidelity simulated patients with live actor‐patients.

Methods:  A prospective cohort study was conducted during two mass casualty drills in December 2006 and March 2007. The providers’ completion of critical actions was tested in live actor‐patients and simulators. A posttest survey compared the participants’ perception of “reality” between the simulators and live actor victims.

Results:  The victims (n = 130) of the mass casualty drill all had burn‐, blast‐, or inhalation‐related injuries. The participants consisted of physicians, residents, medical students, clerks, and paramedics. The authors compared the team’s execution of the 136 critical actions (17 critical actions × 8 scenarios) between the simulators and the live actor‐patients. Only one critical action was missed in the simulator group and one in the live actor group, resulting in a miss rate of 0.74% (95% confidence interval [CI] = 0.01% to 4.5%). All questionnaires were returned and analyzed. The vast majority of participants disagreed or strongly disagreed that the simulators were a distraction from the disaster drill. More than 96% agreed or strongly agreed that they would recommend the simulator as a training tool. The mean survey scores for all participants demonstrated agreement that the simulators closely mimicked real‐life scenarios, accurately represented disease states, and heightened the realism of patient assessment and treatment options during the drill with the exception of nurse participants, who agreed slightly less strongly.

Conclusions:  This study demonstrated that simulators compared to live actor‐patients have equivalent results in prompting critical actions in mass casualty drills and increase the perceived reality of such exercises.
Frontal Sinus Accuracy in Identification as Measured by False Positives in Kin Groups
Authors: Cameriere Roberto , Ferrante Luigi , Molleson Theya , Brown Barry
Published: August 2008

Abstract:  The aims of this study were to verify if frontal sinuses can uniquely identify individuals belonging to family groups using Cameriere methods and to test if kinship can affect the proportion of erroneous identifications. For this purpose, we compared the proportion of false‐positive identifications in a sample of 99 individuals within 20 families with a control sample of 98 other individuals without kinship. The results show that the combined use of SOR and the Yoshino code number allows personal identification with a small probability of false positives (p < 10−6), even when kinship is taken into account. The present research confirms the importance of studying anthropological frameworks for identification, which leads to reliable methods and allows for both quick and economic procedures.
A Metric Method for Sex Determination Using the Proximal Femur and Fragmentary Hipbone*,†
Authors: Albanese John , Eklics Greg , Tuck Andrew
Published: August 2008

Abstract: The pubic bone is considered one of the best sources of information for determining sex using skeletal remains, but can be easily damaged postmortem. This problem has led to the development of nonpelvic methods for cases when the pubic bone is too damaged for analysis. We approached this problem from a different perspective. In this article, we present an approach using new measurements and angles of the proximal femur to recreate the variation in the pubic bone. With a sample from the Terry Collection (n > 300), we use these new variables along with other traditional measurements of the femur and hipbone to develop two logistic regression equations (femur and fragmentary hipbone, and femur only) that are not population specific. Tests on an independent sample (Grant Collection;n = 37–40) with a different pattern of sexual dimorphism resulted in an allocation accuracy of 95–97% with minimal difference by sex.
A general equilibrium analysis of conjunctive ground and surface water use with an application to Morocco
Authors: Diao Xinshen , Dinar Ariel , Roe Terry , Tsur Yacov
Published: August 2008

Groundwater resources (GW) account for nearly 30% of the world's sustainable water supplies. Yet, this resource, which is fraught with externalities, has largely been left unregulated. The economic literature on GW is predominantly of a partial equilibrium type. We analyze GW regulation in a general equilibrium setting, focusing on the stabilization value of GW under natural (drought) and economic (rural–urban water transfer) shocks. A general equilibrium approach allows evaluating direct and indirect effects of GW regulation on agriculture and nonagriculture sectors and extends the scope for water policy. The analysis is applied to Morocco by extending an existing computable general equilibrium (CGE) model to include ground and surface water (SW) resources. We study effects of (i) an increase in GW extraction cost (e.g., as a result of prolonged extraction beyond natural recharge that lowers the aquifer's water table), (ii) a transfer of SW from rural (irrigation) to urban (domestic) use, and (iii) a reduction of water availability due to severe drought. We estimate the value of GW and assess the direct (partial equilibrium) and indirect (general equilibrium) impacts. We find that GW plays a critical role in mitigating the negative effects of these types of shocks.
Measuring impacts and adaptations to climate change: a structural Ricardian model of African livestock management1
Authors: Seo S. Niggol , Mendelsohn Robert
Published: August 2008

This article develops a new cross‐sectional methodology that explicitly incorporates adaptation into an analysis of the impacts of climate change. The methodology examines how a farmer will change choices of species and number to adapt to climate. The approach is applied to study Africa, where the impacts of climate change are expected to be the most severe. The results indicate that in warmer places, African farmers switch from beef cattle to more heat‐tolerant goats and sheep. In wetter places, farmers switch from cattle and sheep to goats and chickens. The results indicate that large commercial livestock operations specializing in beef cattle will be hard hit from climate change whereas small farmers who can easily substitute to goats and/or sheep will be more resilient.
Sheep as capital goods and farmers as portfolio managers: a bioeconomic model of Scandinavian sheep farming
Authors: Skonhoft Anders
Published: August 2008

A model analyzing the economics of sheep farming is formulated. The basic idea is simple. Sheep are capital and they are held by farmers as long as their capital value exceeds their slaughter, or meat, value. Farmers are therefore portfolio managers aiming to find the optimal combination of different categories of animals. Yields are compared with the yields from other assets. The model is formulated within a Northern Scandinavian economic and biological setting with a crucial distinction between the outdoors grazing season and the indoors season, and with adult sheep and lambs being different categories. In the first step, the management problem is analyzed with only the meat income of the farmers taken into account. In the next step, income from wool production is considered as well. The analysis provides several results that differ from standard harvesting theory.
Short‐term clinical effects of adjunctive antimicrobial photodynamic therapy in periodontal treatment: a randomized clinical trial
Authors: Braun Andreas , Dehn Claudia , Krause Felix , Jepsen Søren
Published: August 2008

Objective: The aim of this study was to assess the effect of adjunctive antimicrobial photodynamic therapy (aPDT) in chronic periodontitis.

Material and Methods: Twenty patients with untreated chronic periodontitis were included. All teeth received periodontal treatment comprising scaling and root planing. Using a split‐mouth design, two quadrants (test group) were additionally treated with aPDT. Sulcus fluid flow rate (SFFR) and bleeding on probing (BOP) were assessed at baseline, 1 week and 3 months after treatment. Relative attachment level (RAL), probing depths (PDs) and gingival recession (GR) were evaluated at baseline and 3 months after treatment.

Results: Baseline median values for PD, GR and RAL were not different in the test group and control group. Values for RAL, PD, SFFR and BOP decreased significantly 3 months after treatment in the control group (median delta RAL: −0.35 mm, inter‐quartile range: 0.21 mm), with a higher impact on the sites treated with adjunctive aPDT (median delta RAL: −0.67 mm, inter‐quartile range: 0.36 mm, p<0.05). GR increased 3 months after treatment with and without adjunctive aPDT (p<0.05), with no difference between the groups (p>0.05).

Conclusions: In patients with chronic periodontitis, clinical outcomes of conventional subgingival debridement can be improved by adjunctive aPDT.
Dimensional changes of the alveolar ridge contour after different socket preservation techniques
Authors: Fickl Stefan , Zuhr Otto , Wachtel Hannes , Stappert Christian F. J. , Stein Jamal M. , Hürzeler Markus B.
Published: August 2008

Objectives: The aim of the following study was to assess contour changes after socket preservation techniques.

Material and Methods: In five beagle dogs, the distal root of the third and fourth mandibular premolars was extracted. The following treatments (Tx) were randomly assigned for the extraction socket.

Tx 1: BioOss Collagen.

Tx 2: BioOss Collagen and a free soft tissue graft.

Tx 3: No treatment.

Tx 4: The internal buccal aspect was covered with an experimental collagen membrane, the extraction socket was filled with BioOss Collagen and the membrane folded on top of the graft.

Impressions were obtained at baseline, 2 and 4 months after surgery. Bucco‐lingual measurements were performed using digital imaging analysis.

Results: All groups displayed contour shrinkage at the buccal aspect. Only the differences between the two test groups (Tx 1, Tx 2) and the control group (Tx 3) were significant at the buccal aspect (p0.001). No measurements of the Tx 4 group could be performed.

Conclusion: Socket preservation techniques, used in the present experiment, were not able to entirely compensate for the alterations after tooth extraction. Yet, incorporation of BioOss Collagen seems to have the potential to limit but not avoid the post‐operative contour shrinkage.
Guidelines for the prevention and control of tuberculosis in non‐human primates: recommendations of the European Primate Veterinary Association Working Group on Tuberculosis
Authors: Bushmitz Moshe , Lecu Alex , Verreck Frank , Preussing Ellen , Rensing Susanne , Mätz‐Rensing Kerstin ,   of the EPV‐Tuberculosis Working Group on Non‐human Primate Health
Published: August 2008

Background  Effective tuberculosis (TB) control requires accurate diagnostic methods but the tuberculin skin test has serious limitations. Both false‐negative and false‐positive reactions are common, resulting in the spread of the infection and devastating TB outbreaks. Results of questionnaire surveys concerning TB testing practices in primate housing facilities showed great differences in testing practices. Although there was some uniformity regarding the sites of application, the amounts of tuberculin used and the time intervals for retesting, a great deal of variety was revealed considering the types of tuberculin preparations, the interpretation of tests and the susceptibility of animals.

Conclusion  Here, we summarize the most common practices as regards TB control and prevention for non‐human primates, and attempt to establish a uniform guideline based upon our experience with primate husbandry and care programmes as well as recent developments in the literature. The present guideline represents a consensus recommendation intending to harmonize the existing protocols.
Scar assessment scales: a dermatologic overview
Authors: Idriss Nayla , Maibach Howard I.
Published: August 2008

Background: This overview critically compares subjective assessment tools and available objective measurement tools with potential devices becoming available. Our goal is to lay out the benefits of each scar assessment scale in order to propose good management skills for scars along with strong metric skills.

Methods: Classifying a scar is important in daily clinical practice. Ultimately choosing which treatment modality best fits can become a challenge. Scar classification needs a more detailed and systematic approach. We researched all different factors contributing to scar formation to come up with a more detailed criteria. Such factors included pigmentation/vascularity, surface texture, surface area, thickness (scar height), and pliability.

Results: Few studies have assessed scars; each provided an assessment scale of their own. Each scale is compared on the basis of accuracy, reliability, convenience in terms of feasibility and price.

Conclusions: There remains still no ideal objective measurement out there despite promise seen in subjective evaluation. Method refinement will however accelerate our knowledge and interventions – based on increasing study power with enhanced metrics.
ACADEMIC CREATIVITY UNDER NEW PUBLIC MANAGEMENT: FOUNDATIONS FOR AN INVESTIGATION
Authors: Marginson Simon
Published: August 2008

Abstract In this essay, Simon Marginson focuses on self‐determining academic freedom in universities, and especially the conditions and drivers of the radical‐creative imagination that is manifest in sudden intellectual breaks in knowledge. Marginson’s objective is to establish foundations in political philosophy for a sociological study of the effects of the new public management (NPM) on academic self‐determination and radical creativity. After discussing the radical‐creative imagination, Marginson identifies the core elements of academic self‐determination as agency freedom, freedom as power, and freedom as control. He then annotates each of the particular administrative and financial practices fostered by NPM in the light of these constituents of freedom, explores the implications for the radical‐creative imagination, and identifies possible lines of empirical inquiry for further sociological study.
SIGNIFICANCE AND DIALOGUE IN LEARNING AND TEACHING
Authors: Metcalfe Andrew , Game Ann
Published: August 2008

Abstract In this essay Andrew Metcalfe and Ann Game argue that although the term “dialogue” is commonly used in educational theory, its full significance is diluted if it is seen as a matter of exchange or negotiation of prior positions and identities. As a meeting point, they argue, dialogue suspends the senses of time, space, and ontology on which identities are based. It is therefore not simply metaphorical to say that dialogue changes lives and opens minds. Using empirical material from interviews with Australian students and teachers, Metcalfe and Game draw out the relational qualities of genuine dialogue and the significance they have for how we understand everyday classroom life.
Calcium Dobesilate for the Treatment of Erectile Dysfunction in Men with Diabetes Mellitus
Authors: Videla Sebastián , Villoria Jesús , Sust Mariano , Drábek František , Všetička Jaroslav , Pavlik Ivan , Kawaciuk Ivan , Louda Miroslav , García Carmen , Angulo Javier , Sáenz de Tejada Ínigo
Published: August 2008

Abstract:  Calcium dobesilate has shown to improve endothelial function. This proof‐of‐concept clinical trial was done to check whether it may improve erectile dysfunction in diabetic men. Male diabetic patients with a diagnosis of erectile dysfunction were randomized to receive either calcium dobesilate 1 g twice per day or placebo for 6 weeks. The International Index of Erectile Function (IIEF) was chosen as the primary efficacy measurement. Statistical procedures included a pre‐scheduled adaptive interim analysis to recalculate sample size. Relevant, but not significant differences in the mean change from baseline in the primary end‐point (IIEF questions 3, 4 and 7) favouring dobesilate with respect to placebo were observed. Such differences reached statistical significance in some secondary end‐points, including IIEF global as well as the erectile function and intercourse satisfaction domains’ scores. Some patients experienced an important placebo effect. Results suggest that dobesilate may be of help to treat diabetic erectile dysfunction. Co‐administration with phosphodiesterase inhibitors warrants further investigation.
TECHNICAL EFFICIENCY AND PRODUCTIVITY POTENTIAL OF COCOA FARMERS IN WEST AFRICAN COUNTRIES
Authors: BINAM Joachim Nyemeck , GOCKOWSKI Jim , NKAMLEU Guy Blaise
Published: August 2008

This paper uses survey data to examine the technical efficiency and productivity potential of cocoa farmers in West and Central Africa. Separate stochastic frontier models are estimated for farmers in Cameroon, Ghana, Nigeria, and Côte d’Ivoire, along with a stochastic metaproduction frontier to obtain alternative estimates for the technical efficiencies of farmers in the different countries. The mean productivity potential of cocoa farmers is also estimated, by using a decomposition result applied to both the national and the metaproduction frontiers. The determinants of technical efficiency are assessed to identify the reasons for differences across countries.
Spectrum of GJB2 mutations causing deafness in the British Bangladeshi population
Authors: Bajaj Y. , Sirimanna T. , Albert D.M. , Qadir P. , Jenkins L. , Bitner‐Glindzicz M.
Published: August 2008

Objective:  Mutations in Gap Junction Beta 2 (GJB2) (the gene encoding the protein Connexin 26) have been found to be a major cause of non‐syndromic sensorineural recessive deafness. The mutations in GJB2 causing hearing impairment vary in different populations. The aim of this study was to determine the prevalence and spectrum of GJB2 mutations in prelingual deafness in a population of Bangladeshi origin in the UK.

Design:  Cross‐sectional survey.

Setting:  Community based audiology clinic and tertiary level genetics department.

Methods:  Fifty‐three families (67 patients) with sensorineural hearing loss of unknown cause were included in the study. Detailed history and examination excluded syndromic and environmental causes of hearing loss in the subjects as far as possible. Genetic analysis was performed, specifically looking for mutations in the GJB2 gene.

Results:  Of the 53 families, 14 were confirmed to have biallelic pathogenic mutations in GJB2 (26%). The most common mutations of GJB2 in this population were W24X, IVS1+1, M1V, W77X and Q124X, W24X being the most common mutation seen in 57% of patients.

Conclusion:  Mutations in GJB2 are responsible for over one quarter of non‐syndromic sensorineural deafness in the British Bangladeshi population. It is recommended that all Bangladeshi patients with non‐syndromic hearing loss should be first tested for GJB2 mutations before requesting other aetiological investigations.
Pharyngeal residue across the lifespan: a first look at what’s normal
Authors: Kelly A.M , Macfarlane K , Ghufoor K , Drinnan M.J , Lew‐Gor S
Published: August 2008

Objectives:  Without good evidence, post‐swallow pharyngeal residue is considered abnormal. Our aim was to document residue from normal food and fluid boluses in young and elderly healthy populations.

Design:  Prospective, single‐blind assessment of residue severity from Fibreoptic Endoscopic Evaluation of Swallowing.

Setting:  Tertiary specialist ENT teaching hospital.

Participants:  Fifty‐one healthy participants; twenty‐one aged <40 and thirty aged 65+. Each swallowed six representative boluses.

Outcomes:  Two teams independently rated pharyngeal residue severity at 11 anatomical sites.

Results:  The mean residue scores were less than 1 when averaged across all boluses and anatomic sites. Differences due to age were slight.

Conclusions:  Our preliminary data indicate that substantial pharyngeal residue is not common in young or elderly, and probably indicates disordered swallowing.
The added value of fibreoptic endoscopic evaluation of swallowing in tracheostomy weaning
Authors: Hales P.A. , Drinnan M.J. , Wilson J.A.
Published: August 2008

Objective:  To determine if fibreoptic endoscopic evaluation of swallowing adds information to the clinical assessment of swallowing in tracheostomised patients.

Design:  A prospective, observational study.

Setting:  Addenbrooke’s Hospital, Cambridge, UK.

Participants:  Twenty‐five consecutive, adult, tracheostomised patients were recruited over a 3‐month period. They were referred to speech and language therapy for a swallowing assessment and were ready to trial cuff deflation.

Main outcome measures:  In current practice the clinical assessment is invariably a precursor to fibreoptic endoscopic evaluation of swallowing and a test would be considered positive when penetration or aspiration are detected. We considered the value of fibreoptic endoscopic evaluation of swallowing following both positive and negative outcomes of the clinical assessment.

Results:  The positive predictive value of aspiration or penetration was 91% i.e. when a clinical assessment is failed, there is a very high probability the patient would also be failed on fibreoptic endoscopic evaluation of swallowing. However, the negative predictive value was only 64% i.e. over one‐third of patients who pass a clinical assessment would later fail a fibreoptic endoscopic evaluation of swallowing.

Conclusions:  Despite a small cohort, our data suggest that the assessment of swallowing to aid weaning in tracheostomised patients is currently performed incorrectly; we estimate that over a third of all tracheostomised patients that ‘pass’ the clinical assessment of swallowing are, in reality, at risk from penetration, aspiration or failed decannulation. This finding supports the use of fibreoptic endoscopic evaluation of swallowing and a change in clinical practice.
Acceptability of Micronutrient Fortified School Meals by Schoolchildren in Rural Himalayan Villages of India
Authors: Osei A.K. , Houser R.F. , Bulusu S. , Hamer D.H.
Published: August 2008

ABSTRACT:  This cross‐sectional randomized controlled study assessed the social acceptability of micronutrient fortified cooked lunch meals by schoolchildren in rural Himalayan villages of India, in a program where the cooking and the micronutrient fortification were done at school. Subjects were randomly assigned to treatment (91) and control (90) groups. The treatment group consumed a weighed amount of cooked lunch meals fortified with locally produced multi‐micronutrient premix and the control group consumed a weighed amount of the same meals but without added micronutrient premix. After having eaten, subjects were asked to rate, on a 3‐point Likert scale using “smiley” faces, the pleasantness of smell, taste, and overall satisfaction with the food. The mean age of study children was 7.96 ± 1.64 y and 48.6% were males. The average amounts of food consumed by the treatment and control groups were 345 ± 114 and 360 ± 102.4 g, respectively. Addition of the multi‐micronutrient premix to school meals did not significantly affect the mean amount of food consumed by the schoolchildren (P > 0.05; independent sample t‐test). No significant differences were seen between treatment and control groups in terms of ratings for taste, smell, and the general acceptance of the micronutrient fortified or the unfortified school meals. In conclusion, the addition of a multiple micronutrient premix to school meals was well liked by schoolchildren and did not adversely affect their food consumption.
Short‐term UV Exposure of Sunbathers at a Mediterranean Sea Site
Authors: Siani Anna Maria , Casale Giuseppe Rocco , Sisto Renata , Borra Massimo , Kimlin Michael G. , Lang Carolyn A. , Colosimo Alfredo
Published: August 2008

The aim of this study was to investigate whether systematic differences in solar UV exposure on a specific anatomical site (chest) exist among three groups of Italian sunbathers: healthy subjects (suntanned and non‐suntanned individuals) and subjects affected by abnormally high sensitivity to solar exposure. A second aim of the study was to search for a possible relation among biological markers of individual response to UV exposure (such as skin colorimetric parameters, skin temperature and changes in free radical amounts [FR] in the blood) and photosensitivity. FR in the blood were analyzed because of their possible influence on UV carcinogenesis. Measurements of ambient doses (i.e. incident erythemally weighted irradiance on a horizontal surface over a specified period of time) and erythemally effective UV dose received by an anatomical site (here called personal dose or exposure on a specific anatomical site) were investigated. Personal doses received by the chest were determined using polysulfone dosimetry. Exposure Ratio (ER), defined as the ratio between the personal dose and the corresponding ambient dose during the same exposure period, was then calculated. Measuring of skin color in the Commission Internationale de l’Eclairage L* (luminance), a* (redness), b* (yellowness) system and skin temperature were also carried out on the inner upper arm (nonexposed skin site) and on the chest. It was found that the median value of ER was 0.20 (min: 0.09 and max: 0.34) for suntanned individuals, it was 0.17 (min: 0.13 and max: 0.42) for non‐suntanned individuals and it was 0.19 (min: 0.14 and max: 0.34) for photosensitive individuals. There were no significant differences across the groups in their median ER scores. In addition, the statistical analysis showed that L* on the exposed site before exposure demonstrated consistently higher median scores after exposure in all groups. The b* value after exposure was significantly lower than before exposure in all participants, while no significant differences for a* were observed before or after exposure between or within the groups. Our findings suggest that photodermatoses are not significantly related to ER and to the changes in biological markers due to too short‐term UV exposure.
Results of Increasing Doses of Hydrochlorothiazide in Combination With an Angiotensin Receptor Blocker in Patients With Uncontrolled Hypertension
Authors: Neldam Steen , Edwards Colin
Published: August 2008

This study examined the effects of increasing the thiazide diuretic dose in a fixed‐dose ARB/diuretic combination in patients with uncontrolled hypertension despite 6 weeks' open‐label treatment with the ARB/diuretic combination, telmisartan 80 mg/hydrochlorothiazide 12.5 mg (T80/H12.5). 713 patients with trough seated DBP =90 mmHg were then randomized to 8 weeks' double‐blind treatment with telmisartan 80 mg and an increased dose of 25 mg of hydrochlorothiazide (T80/H25) or T80/H12.5. Adjusted mean seated DBP changes from baselines of 95.3 (T80/H25) and 95.0 mmHg (T80/H12.5) were −7.1 and ‐−5.5 mmHg (difference: 1.6 mm Hg), respectively (P=.0012). Changes in systolic blood pressure from 147.9 mmHg (T80/H25) and 147.4 mmHg (T80/H12.5) were −9.8 and −7.1 mmHg (difference: 2.7 mm Hg) (P=.0003). Adverse events occurred in 31.5% (T80/H25) and 29.6% (T80/H12.5), with serious events in 1.4% and 0.8%, respectively. Hypokalemia was rare. These results show that higher‐dose thiazide diuretic in combination with T80 in patients with hypertension uncontrolled by T80/H12.5 provides additional blood pressure reductions and is well tolerated.
Dietary Management in the Prevention and Treatment of Hypertension: Does It Work?
Authors: Moser Marvin , Houston Mark , Svetkey Laura , Egan Brent
Published: August 2008

During a meeting of the American Society of Hypertension in New Orleans, LA, in May 2008, an expert panel was convened to discuss nonpharmacologic therapy in hypertension. This is an update of a panel discussion that was held in March 2007. The panel was co‐moderated by Marvin Moser, MD, Clinical Professor of Medicine at Yale University School of Medicine, New Haven, CT, and Mark Houston, MD, Associate Clinical Professor at the Vanderbilt University School of Medicine, Nashville, TN. Panelists included Laura Svetkey, MD, Professor of Medicine at Duke University, Durham, NC, and Brent Egan, Professor of Medicine at the Medical University of South Carolina, Charleston, SC.
Use of differential expression data for identification of novel immune relevant expressed sequence tag‐linked microsatellite markers in Atlantic salmon (Salmo salar L.)
Authors: TONTERI A. , VASEMÄGI A. , LUMME J. , PRIMMER C. R.
Published: August 2008

Despite the large number of genes contributing to the immune response, wildlife immunogenetic studies have tended to focus mostly on the major histocompatibility complex‐related genes. Here, we utilized previously published microarray and competitive RNA hybridization information to identify 3750 immune relevant Atlantic salmon (Salmo salar) expressed sequence tags. We then identified those expressed sequence tags containing microsatellites and subsequently designed 48 primer pairs and tested them for polymorphism in Atlantic salmon. Altogether, 16 polymorphic markers were characterized, with allele numbers ranging from two to 18, and these 16 loci were further tested in five other salmonid species.
Susceptibility of selected tooth‐coloured dental materials to damage by common erosive acids
Authors: Wan Bakar WZ , McIntyre J
Published: August 2008

Background:  Erosive substances such as gastric acids, lemon juice and even the less erosive cola drinks have been extensively investigated for their destructive effects on enamel. However, their effects on the tooth‐coloured restoratives has not been widely analysed. The objective of this study was to assess their effects on the more commonly used glass containing restorative materials in vitro.

Materials and methods:  Sixty‐eight anterior and 24 molar tooth crowns had restorations placed of Fuji IX, Ketac Fil+, Fuji II LC or Z100, and were painted with nail varnish to leave a 2 mm border around the restorations. Six ceramic crown surfaces were also included. The anterior crowns and porcelain samples were exposed to 0.113% HCl, 5.0% citric acid, 0.02% orthophosphoric acid or DDW for 2, 4, 8 or 16 hours at 37°C. The molar restorations were exposed only for 16 hours. The surfaces of the anterior teeth were then examined by SEM to assess progressive stages of surface erosive etching. Depths of bulk loss of vulnerable restorative materials were measured in the remaining 24 molar teeth, and compared with depths of adjacent enamel loss, particularly at the margins, using Leika Microscope images of sections through these restorations.

Results:  The traditional glass ionomer cements (GICs) were severely eroded by the HCl and citric acid solutions even following two hours of exposure, with only minor damage from phosphoric acid at the concentration tested. These materials experienced considerable bulk loss by 16 hours, comparable to or greater than that in adjacent enamel. The margins of the GIC restorations experienced greater dissolution than the body of the restorations, particularly in citric acid. Z100 Resin Composite and porcelain restorations showed no effects at all, and Fuji II LC only minor damage.

Conclusions:  The results demonstrate the effectiveness of porcelain and resin containing materials in providing protection of enamel in advanced cases of erosion. The traditional GIC materials are vulnerable to severe damage in patients experiencing strong citric acid or gastric acid induced erosion. However, there is evidence that protective benefits are still present and these materials should be used but only in closed sandwich restorations in such cases.
A clinical trial comparing two all‐in‐one adhesive systems used to restore non‐carious cervical lesions: results at one year
Authors: Burrow MF , Tyas MJ
Published: August 2008

Background:  Few data exist with respect to the clinical performance of all‐in‐one adhesive systems. However, their clinical use is increasing. The aim of this study was to evaluate the retention and marginal staining of resin composite restorations bonded with Clearfil S3 Bond or G‐Bond all‐in‐one systems placed in non‐carious cervical lesions.

Materials and methods:  Sixty restorations were placed in 11 subjects, mean age 62.5 years. Approval for the clinical trial was obtained from the Human Ethics Committee of The University of Melbourne. Restorations were bonded and placed according to the manufacturers’ instructions. No enamel etching was performed on the enamel margins prior to restoration placement. Patients were recalled at six months, and one year for evaluation of presence and marginal staining. Photographic records were obtained prior to restoration, immediately after and at recall.

Results:  All patients could be recalled. All restorations were present at both recall periods. A 100 per cent retention rate was obtained. Slight marginal staining was observed on four restorations for S3 and three restorations for G‐Bond.

Conclusions:  The early results of this clinical evaluation showed good outcomes for both materials.
Prevalence of developmental enamel defects of the first permanent molars among school children in Western Australia
Authors: Arrow P
Published: August 2008

Background:  The prevalence of enamel defects in the first permanent molars among children has been reported to be high and may be on the increase, particularly in the European countries. Little information is available on the prevalence of enamel defects in the first permanent molars among children in Australia. The aim of this study was to describe the prevalence of enamel defects in the first permanent molars among school children in Western Australia.

Methods:  Informed consent was obtained from parents of children attending pre‐primary schools within an administrative area of the School Dental Service of Western Australia in metropolitan Perth to participate in the study in 2005. Parents completed a questionnaire about the mother’s health status during pregnancy, and their child’s health status for the first three years. Participating children were examined during 2006 and 2007 by one examiner. Teeth were classified on the type and extent of enamel defects using the modified DDE index, and deciduous tooth caries experience of molars and canines was recorded using the WHO criteria.

Results:  Parents of 634 children out of the eligible 1135 (56 per cent participation) completed the questionnaire. Five hundred and eleven children with at least one erupted first permanent molar were examined (mean age 7.1 years, SD 0.5). Of the first permanent molars, 42 per cent upper right; 37 per cent upper left; 47 per cent lower left; and 45 per cent lower right were without enamel defects. White diffuse opacities were the predominant enamel defects found with 46 per cent upper right; 47 per cent upper left; 40 per cent lower left and 41 per cent lower right molars affected. Demarcated opacities alone or in association with other defects affected 11 per cent upper right; 14 per cent upper left; 10 per cent lower left and 9 per cent lower right molars. At the individual level, 71 per cent had permanent molars with enamel defects; 47 per cent with white diffuse opacities and 22 per cent with demarcated opacities.

Conclusions:  Prevalence of enamel defects among this school population is high. Majority of defects were white diffuse opacities and the prevalence of demarcated opacities is at the high end of that reported for some European countries. Possible risk factors for enamel defects remains to be tested.
Conservative treatment of a cervical horizontal root fracture and a complicated crown fracture: a case report
Authors: Belobrov I , Weis MV , Parashos P
Published: August 2008

This case report describes successful long‐term conservative management of a cervical root fracture and a complicated crown fracture of the maxillary central incisors in a 12‐year‐old patient. A mineral trioxide aggregate partial pulpotomy was performed on the maxillary right central incisor, while the maxillary left central incisor was splinted to the neighbouring lateral incisor using an acid‐etch technique. Both teeth remained asymptomatic throughout the 3.5 years of a review period, with the cervical root fracture having mostly healed with the formation of a calcified tissue between the fragments. Two different treatment methods were used for two different injuries that resulted in pulp preservation in both cases. This in turn has provided for normal root development to occur while also allowing for preservation of bone.
Calcium phosphate‐based remineralization systems: scientific evidence?
Authors: Reynolds EC
Published: August 2008

Dental caries remains a major public health problem in most communities even though the prevalence of disease has decreased since the introduction of fluorides. The focus in caries research has recently shifted to the development of methodologies for the detection of the early stages of caries lesions and the non‐invasive treatment of these lesions. Topical fluoride ions, in the presence of calcium and phosphate ions, promote the formation of fluorapatite in tooth enamel by a process referred to as remineralization. The non‐invasive treatment of early caries lesions by remineralization has the potential to be a major advance in the clinical management of the disease. However, for net remineralization to occur adequate levels of calcium and phosphate ions must be available and this process is normally calcium phosphate limited. In recent times three calcium phosphate‐based remineralization systems have been developed and are now commercially available: a casein phosphopeptide stabilized amorphous calcium phosphate (RecaldentTM (CPP‐ACP), CASRN691364‐49‐5), an unstabilized amorphous calcium phosphate (ACP or EnamelonTM) and a bioactive glass containing calcium sodium phosphosilicate (NovaMinTM). The purpose of this review was to determine the scientific evidence to support a role for these remineralization systems in the non‐invasive treatment of early caries lesions. The review has revealed that there is evidence for an anticariogenic efficacy of the EnamelonTM technology for root caries and for the RecaldentTM technology in significantly slowing the progression of coronal caries and promoting the regression of lesions in randomized, controlled clinical trials. Hence the calcium phosphate‐based remineralization technologies show promise as adjunctive treatments to fluoride therapy in the non‐invasive management of early caries lesions.
Dental caries: a dynamic disease process
Authors: Featherstone JDB
Published: August 2008

Dental caries is a transmissible bacterial disease process caused by acids from bacterial metabolism diffusing into enamel and dentine and dissolving the mineral. The bacteria responsible produce organic acids as a by‐product of their metabolism of fermentable carbohydrates. The caries process is a continuum resulting from many cycles of demineralization and remineralization. Demineralization begins at the atomic level at the crystal surface inside the enamel or dentine and can continue unless halted with the end‐point being cavitation. There are many possibilities to intervene in this continuing process to arrest or reverse the progress of the lesion. Remineralization is the natural repair process for non‐cavitated lesions, and relies on calcium and phosphate ions assisted by fluoride to rebuild a new surface on existing crystal remnants in subsurface lesions remaining after demineralization. These remineralized crystals are acid resistant, being much less soluble than the original mineral.
Studies of Carbon Nanotube Based Composites for Aerospace Applications
Authors: Bellucci S. , Micciulla F. , Balasubramanian C. , Grilli A. , Rinaldi G.
Published: August 2008

Carbon nanotubes are being widely studied for various applications ranging from medical to electronics and also optical devices. They are also being studied for the suitability and applications in aerospace and aeronautical field. A useful application in aerospace that we are studying is the improvement of electrical properties of composites made from carbon nanotubes and epoxy resin. Towards this end, we have studied the resistivity of composite materials with varying percentages of carbon nanotubes (CNT) added to the epoxy resin. Carbon nanotubes were synthesized by thermal arc plasma process after optimization of the synthesis parameters. These samples were then analysed by electron microscopes like scanning electron and transmission electron microscopes (SEM and TEM), in order to establish the morphology of the nanostructures. Composites of epoxy resin with curing agent as well as a mixture of graphite and carbon nanotubes were prepared with varying proportions of the mixture. The electrical resistivity of the material was studied under varying pressure and voltage conditions. The result of these studies yields interesting features which are useful in choosing the ideal composition and ratio of the composite material for use in shielding of electrical circuits of space vehicles from radiations of the outer space.
Analytical Evaluation of Shear Properties of Polymer Nanocomposites
Authors: Park Jin Y.
Published: August 2008

This paper presents an analytical investigation aimed at examining the mechanical behavior of polymer micro/nanocomposites containing nonhomogeneous constituents under shear loading. Analytical models that account for the presence of the hexagonal platelet shaped clay particles and voids in matrix materials were developed for estimating in-plane shear modulus. The analytical results were compared with the properties obtained from an experimental program. For the experiment, vinylester polymer composites containing clay fillers and voids were selected, analyzed and tested under shear loading. The effects of presence of constituents on the mechanical properties of matrix materials were also investigated based on the obtained volume fraction of their constituents.
Micropropulsion Development at the ARC Seibersdorf Research
Authors: Scharlemann Carsten Arthur , Tajmar Martin
Published: August 2008

The increasing application of micro-satellites (from 10 kg up to 100 kg) for a rising number of various missions demands the development of new miniaturized propulsion systems. Micro-satellites have special requirements for the propulsion system such as small mass, reduced volume, and very stringent electrical power constraints. Existing propulsion systems often can not satisfy these requirements. The Space Propulsion Department of the ARC Seibersdorf research dedicated itself to the development and test of various micropropulsion systems for present and future space missions. The portfolio of the systems under development includes electrical and chemical propulsion systems. The covered thrust and specific impulse of the developed propulsion systems ranges from 1μN to 1N and 500 s to 8000 s respectively. Based on the large experience obtained over several decades in the development of Field Emission Electric Propulsion systems (FEEP), several microstructured FEEPs have been developed. The design of these systems is presented as well as preliminary test results and a summarization of the experience obtained during the process of miniaturizing such systems. The development of miniaturized chemical propulsion systems includes a bipropellant and a monopropellant thruster. The bipropellant thruster constitutes the smallest existing 1N thruster utilizing hydrogen peroxide. The thruster system consists of two micopumps for the propellant feed and a microturbine to generate the power for operating the pumps. The monopropellant thruster is a derivative of the bipropellant thruster. It offers a lower specific impulse than the bipropellant system but due to its reduced system complexity it represents also a promising candidate for several future space missions. Both systems utilize rocket grade hydrogen peroxide (green propellant), which is decomposed with the help of an advanced monolithic catalyst. The present paper discusses the design methods and the physical limitations of such chemical propulsion systems with regard to their miniaturization and summarizes their performance evaluation.
On the Use of Wearable Computing in Aircraft Maintenance: First Results From WearIT@work
Authors: Lawo Michael , Boronowsky Michael , Herzog Otthein
Published: August 2008

Currently wearable computing is still a technology of niches and in a laboratory stage. With wearIT@work a project dedicated to applications was launched by the European Commission. The first 18 months of the project are over and the first demonstrators and results were achieved. As the project strongly follows a cyclic and user centred design approach much effort was put on investigations with end users in the four application domains of aircraft maintenance, production, healthcare and emergency response. Demonstrators of wearable computing solutions were achieved and evaluations with end users performed. In this paper the research concept of the project is introduced and results from the wearable computing aircraft maintenance show case are presented.
Damping Properties/Dynamics of Nanoparticle-Reinforced Material
Authors: Kireitseu M. V.
Published: August 2008

Nanoparticle-based vibration damping shows the effect that molecule-level mechanism can have on the damping and that nanostructured composite materials can provide enhanced strength/vibration damping properties over broader operational conditions. The focus in this paper is directed toward to some aspects of engineering applications of nanoparticles and the development of the next generation of vibration damping systems, providing a road map to manufacturing technology and design concepts so as to enable interested researchers and aerospace/automotive practitioners lead this direction.
Robust GaN Electronics for Highly Reliable BF and RF Analog Systems in Aerospace Applications
Authors: Soubercaze-Pun G. , Tartarin J. G. , Bary L. , Rayssac J. , Delage S. , Graffeuil G.
Published: August 2008

The reliability and robustness of electronic sub-systems dedicated to control and communications in the aerospace sector is more than ever one of the key points for safety and security, essentially during landing operations. As aircraft manufacturers have to diversify their mean of communication system’s control (Full-Duplex and System), the reliability can be improved both by setting redundant remote networks, and also by using matched technologies for increased performances and robustness: the wide band-gap Gallium Nitride technology (GaN) newly developed fits perfectly to the requirements of systems such as Microwave Landing System (MLS) or Distance Measuring Equipments (DME) used during the final landing approach. Actually, GaN technology takes advantage of a natural immunity to electromagnetic perturbations, and is suitable for circuit design in the RF frequency band (up to 5 GHz for aircraft applications). The GaN based circuits are able to improve transceiver’s efficiency (and so the radio-link budget) thanks to their low noise figure (receiver) and high output power (transmitter), reducing digital bit error rate during the code demodulation. This point is crucial while electronic runs in an urban environment. Moreover, the next electronic systems developed for “composite aircraft” will be more exposed to high electric field and CEM problems in circuits. Furthermore, this GaN integrated technology allows a reduction of volume for transmitter’s sub-systems, and is easy to setup (aircraft maintenance): the risk of immobilisation during the aircraft exploitation will be reduced and his maintainability will be easier. Finally, this technology is also perfectly suited for ground navigation control systems such as radar. This work presents the challenge for civil and military future avionic systems by making use of GaN based technologies.