Undergraduate student experience in dental service delivery in rural South Australia: An analysis of costs and benefits

Background, Rural experience for dental students can provide valuable clinical education, change attitudes to rural practice, and make a valuable contribution to clinical service provision. The aim of this paper is to assess the costs and benefits of service delivery by students through rural training programmes Methods: Groups of two students worked in the public dental clinics in adjacent rural centres where there had been long-term difficulties in recruiting staff. The costs and benefits of the programme were assessed by the impact on waiting lists, the total cost per patient of, a course of care and by the marginal cost of adding service provision by students to existing arrangements. Results: The total costs of emergency and complete treatment provided by students were greater than the costs of treatment provided by public-sector dentists but less than the costs of private providers treating public patients. However, the value of services were greater when care was provided by students or private providers and the marginal cost of students providing services was 50-70 per cent of the cost of care provided by public dentists. Conclusion: This assessment suggests that the service benefits achieved compliment the primary objective of influencing the attitude of students to rural practice.

Ecological interface design for pasteurizer II: A process description of semantic mapping

Ecological interface design (EID) is proving to be a promising approach to the design of interfaces for complex dynamic systems. Although the principles of EID and examples of its effective use are widely available, few readily available examples exist of how the individual displays that constitute an ecological interface are developed. This paper presents the semantic mapping process within EID in the context of prior theoretical work in this area. The semantic mapping process that was used in developing an ecological interface for the Pasteurizer II microworld is outlined, and the results of an evaluation of the ecological interface against a more conventional interface are briefly presented. Subjective reports indicate features of the ecological interface that made it particularly valuable for participants. Finally, we outline the steps of an analytic process for using EID. The findings presented here can be applied in the design of ecological interfaces or of configural displays for dynamic processes.

Structure-activity relationships of alpha-conotoxins targeting neuronal nicotinic acetylcholine receptors

alpha-Conotoxins that target the neuronal nicotinic acetylcholine receptor have a range of potential therapeutic applications and are valuable probes for examining receptor subtype selectivity. The three-dimensional structures of about half of the known neuronal specific alpha-conotoxins have now been determined and have a consensus fold containing a helical region braced by two conserved disulfide bonds. These disulfide bonds define the two-loop framework characteristic for alpha-conotoxins, CCXmCXnC, where loop 1 comprises four residues (m = 4) and loop 2 between three and seven residues (n = 3, 6 or 7). Structural studies, particularly using NMR spectroscopy have provided an insight into the role and spatial location of residues implicated in receptor binding and biological activity.

Intra- and interspecific divergence in the nuclear sequences of the clock gene period in species of the Drosophila buzzatii cluster

We have measured nucleotide variation in the CLOCK/CYCLE heterodimer inhibition domain (CCID) of the clock X-linked gene period in seven species belonging to the Drosophila buzzatii cluster, namely D. buzzatii, Drosophila koepferae, Drosophila antonietae, Drosophila serido, Drosophila gouveai, Drosophila seriema and Drosophila borborema. We detected that the purifying selection is the main force driving the sequence evolution in period, in agreement with the important role of CCID in clock machinery. Our survey revealed that period provides valuable phylogenetic information that allowed to resolve phylogenetic relationships among D. gouveai, D. borborema and D. seriema, which composed a polytomic clade in preliminary studies. The analysis of patterns of intraspecific variation revealed two different lineages of period in D. koepferae, probably reflecting introgressive hybridization from D. buzzatii, in concordance with previous molecular data.

Reserve price commitments in auctions

It is well known that the optimal auction-one that maximizes the seller's expected revenue-can be implemented using a standard auction format with a suitably chosen reserve price. This reserve price is above the seller's value of retaining the object and the mechanism requires a commitment not to sell the object below the reserve. This commitment is what makes the reserve valuable to the seller. However, in practice, a reserve price commits the seller to sell the object if the reserve is reached, but does not commit her to withhold the object from sale if bidding falls short of the reserve. In this note we investigate whether reserve prices remain valuable for the seller when she may negotiate with the highest bidder if the reserve is not met. We show that the value of the reserve price may be completely undermined if the seller is a sufficiently weak bargainer. (c) 2004 Elsevier B.V. All rights reserved.

On Reciprocal Illumination and Consilience in Biogeography

Biogeography deals with the combined analysis of the spatial and temporal components of the evolutionary process. To this purpose, biogeographical analysis should consider two extra steps: a reciprocal illumination step, and a consilience step. Even if the traditional challenges of biogeography were successfully handled, the obtained hypothesis is not necessarily meaningful in biogeographical terms--it needs continuous test in the light of external hypotheses. For this reason, a concept analogous to Hennig`s reciprocal illumination is valuable, as well as a sort of biogeographical consilience in Whewell`s sense. Firstly, through the search for different classes of evidence, information useful to improve the hypothesis can be accessed via reciprocal illumination. Following, a more general hypothesis would arise through a consilience process, when the hypothesis explains phenomena not contemplated during its construction, as the distribution of other taxa or the existence (or absence) of fossils. This procedure aims to evaluate the robustness of biogeographical hypotheses as scientific theories. Such theories are reliable descriptions of how life changes its form both in space and time, putting historical biogeography close to Croizat`s statement of evolution as a three dimensional phenomenon.

Factors influencing organisational silence

Organisadonal silence is a recendy introduced area of business research that seeks to address why employees fail to express ideas, informadon and opinions that can effecdvely improve organisadonal effecdveness. In making a start to understand silence, the majority of frameworks have suggested that employees withhold valuable input from management because they believe that it is too personally cosdy to speak up, and/or management are unMkely to take acdon about their ideas or concerns. Because today's workforce are largely required to work in groups or teams, one of the primary aims of this paper is to provide a deeper understanding of this phenomenon by focusing on group process factors that are likely to drive silence. Research that consider the group perspecdve indicate that one's ingroup posidon (i,e,, pro to typicality), and the accumuladon of idiosyncrasy credits (i,e,, leeway to offer innovadve ideas) are likely to play a role in whether (or not) people speak up. For example, those on the periphery of the group or less prototypical group members may need to conform strenuously to group norms in order to improve their ingroup posidon. Similarly, those who have accrued few idiosyncrasy credits may need to conform to group expectadons in order to accumulate sufficient "resources" to deviate from group norms, and be taken seriously by other group members. Thus, the conceptual framework proposed is underpinned by the social idendty perspecdve as well as the nodon of idiosyncrasy credits.

Binge eating symptoms, diet composition and metabolic characteristics of obese children and adolescents

This study aimed to determine the occurrence of symptoms of binge eating (BE) among children and adolescents seeking treatment for their obesity, as well as to evaluate their diet composition and metabolic characteristics. The Binge Eating scale (BES) was answered by 128 children and adolescents (10.77 +/- 2.04 years, BMI 29.15 +/- 4.98 kg/m(2), BMI Z score 2.28 +/- 0.46, 53.91% pubescent), who were classified into two subgroups-binge eaters (score greater than or equal to IS points) and non-binge eaters (score lower than 18 points). Anthropometric data, body composition and Tanner stages were collected and dietary evaluation conducted. Blood pressure was determined, and glucose, lipid profile and insulin assays were performed. insulin resistance was determined using HOMA-IR. BE symptoms were present in 39.06% of patients. Carbohydrate intake in diet composition was significantly higher among binge eaters. Children with BE did not demonstrate significant dissimilar metabolic characteristics when compared to their counterparts without BE. Therefore, BE seems to be a prevalent problem among children and adolescents seeking help for their obesity. When associated with obesity, this eating behaviour can influence macronutrient consumption through increased carbohydrate intake. Further research would be valuable to verify the reproducibility of these findings. (c) 2007 Elsevier Ltd. All rights reserved.

Magnetic resonance imaging of idiopathic carpal tunnel syndrome: Correlation with clinical findings and electrophysiological investigation

Objective: To compare clinical evaluation, electrophysiological investigation and magnetic resonance findings in assessing the severity of idiopathic carpal tunnel syndrome. Patients and methods: Seventy-four patients with idiopathic carpal tunnel syndrome were prospectively recruited. Clinical evaluation included symptoms severity score and two-point discrimination, sensory and motor nerve conduction velocities were determined by electroneuromyography and imaging parameters were obtained after wrist magnetic resonance. The Wilcoxon test was used to define the differences between measurements of median nerve area. The Pearson and Spearman correlation tests were used to determine the relationships between all the measured parameters. Results: Cross-sectional area of median nerve was smaller at hamate level than at radio-ulnar joint and pisiform levels (p < 0.001). With exception of median nerve area at hamate level, there was a lower degree of correlation between MRI parameters and findings obtained by clinical assessments and electrophysiological measurements. The median nerve area at hamate level correlated negatively with duration of symptoms, two-point discrimination, symptoms severity score and positively with sensory nerve conduction velocity (P < 0.01). Conclusion: In patients with idiopathic carpal tunnel syndrome, median nerve area measured by wrist magnetic resonance at hamate level may be considered as a valuable indicator to grading the severity of disease. (c) 2007 Elsevier B.V. All rights reserved.

Computed tomographic assessment of lung weights in trauma patients with early posttraumatic lung dysfunction

Introduction: Quantitative computed tomography (qCT)-based assessment of total lung weight (M(lung)) has the potential to differentiate atelectasis from consolidation and could thus provide valuable information for managing trauma patients fulfilling commonly used criteria for acute lung injury (ALI). We hypothesized that qCT would identify atelectasis as a frequent mimic of early posttraumatic ALI. Methods: In this prospective observational study, M(lung) was calculated by qCT in 78 mechanically ventilated trauma patients fulfilling the ALI criteria at admission. A reference interval for M(lung) was derived from 74 trauma patients with morphologically and functionally normal lungs (reference). Results are given as medians with interquartile ranges. Results: The ratio of arterial partial pressure of oxygen to the fraction of inspired oxygen was 560 (506 to 616) mmHg in reference patients and 169 (95 to 240) mmHg in ALI patients. The median reference M(lung) value was 885 (771 to 973) g, and the reference interval for M(lung) was 584 to 1164 g, which matched that of previous reports. Despite the significantly greater median M(lung) value (1088 (862 to 1,342) g) in the ALI group, 46 (59%) ALI patients had M(lung) values within the reference interval and thus most likely had atelectasis. In only 17 patients (22%), Mlung was increased to the range previously reported for ALI patients and compatible with lung consolidation. Statistically significant differences between atelectasis and consolidation patients were found for age, Lung Injury Score, Glasgow Coma Scale score, total lung volume, mass of the nonaerated lung compartment, ventilator-free days and intensive care unit-free days. Conclusions: Atelectasis is a frequent cause of early posttraumatic lung dysfunction. Differentiation between atelectasis and consolidation from other causes of lung damage by using qCT may help to identify patients who could benefit from management strategies such as damage control surgery and lung-protective mechanical ventilation that focus on the prevention of pulmonary complications.

New gene technologies and their potential value for sugarcane

An efficient system is now in place for improving diverse sugarcane cultivars by genetic transformation, that is, the insertion of useful new genes into single cells followed by the regeneration of genetically modified (transgenic) plants. The method has already been used to introduce genes for resistance to several major diseases, insect pests and a herbicide, Field testing has begun, and research is underway to identify other genes for increased environmental stress resistance, agronomic efficiency and yield of sucrose or other valuable products. Experience in other crops has shown that genetically improved varieties which provide genuine environmental and consumer benefits are welcomed by producers and consumers. Substantial research is still needed, but these new gene technologies will reshape the sugar industry and determine the international competitive efficiency of producers.

High-titer antichromatin antibody is associated with proliferative class IV of lupus nephritis

The antichromatin antibody (aCT) has been described as a useful marker for lupus nephropathy. The relevance of its nephritogenic potential may be appropriately evaluated in the context of renal histopathology. Therefore, the present study investigated the relationship of aCT with a particular histopathologic class of lupus nephritis (LN). Seventy-eight consecutive patients with systemic lupus erythematosus (ACR criteria) and active nephritis who underwent renal biopsy from 1999 to 2004 and with available frozen serum sample obtained at the time of biopsy were selected. aCT was measured by ELISA, and anti-dsDNA was measured by indirect immunofluorescence (IIF) and by ELISA. All renal biopsies were revised in a blinded manner by the same expert renal pathologist. Charts were extensively reviewed for demographic and renal features obtained at the time of biopsy. The prevalence of aCT (>= 20 U) was 59% with a mean titer of 74.3 +/- 38.7U. Both aCT-positive and aCT-negative groups of patients had similar age, gender distribution, duration of lupus, and duration of renal disease. Anti-dsDNA was detected by IIF in 29.5% and by ELISA in 42.3% of the patients. Concomitant presence of both antibodies was observed in 63% (29/46) [anti-dsDNA by ELISA] and 45.6% (21/46) [anti-dsDNA by IIF] of the patients. Lower serum levels of C3 (73% vs. 40%, P=0.0058) and C4 (82% vs. 46.7%, P=0.0021) were more commonly observed in aCT >= 20 U patients compared to the aCT-negative group. It is important to note that the use of a higher cut-off value (>= 40 U) for aCT test revealed a predominance of class IV LN (58% vs. 33%, P=0.039) in aCT >= 40 U compared to aCT<40 U group. The mean levels of proteinuria, serum albumin, and creatinine were markedly altered but were comparable in both groups (P >= 0.05). One fourth (26.3%) of the 19 patients with class IV LN and aCT >= 40 U had no detectable anti-dsDNA (ELISA). These data suggest that high-titer aCT seems to be a valuable biomarker for proliferative class IV of LN.

Solution structure of the sodium channel antagonist conotoxin GS: A new molecular caliper for probing sodium channel geometry

Background: The venoms of Conus snails contain small, disulfide-rich inhibitors of voltage-dependent sodium channels. Conotoxin GS is a 34-residue polypeptide isolated from Conus geographus that interacts with the extracellular entrance of skeletal muscle sodium channels to prevent sodium ion conduction. Although conotoxin GS binds competitively with mu conotoxin GIIIA to the sodium channel surface, the two toxin types have little sequence identity with one another, and conotoxin GS has a four-loop structural framework rather than the characteristic three-loop mu-conotoxin framework. The structural study of conotoxin GS will form the basis for establishing a structure-activity relationship and understanding its interaction with the pore region of sodium channels. Results: The three-dimensional structure of conotoxin GS was determined using two-dimensional NMR spectroscopy. The protein exhibits a compact fold incorporating a beta hairpin and several turns. An unusual feature of conotoxin GS is the exceptionally high proportion (100%) of cis-imide bond geometry for the three proline or hydroxyproline residues. The structure of conotoxin GS bears little resemblance to the three-loop mu conotoxins, consistent with the low sequence identity between the two toxin types and their different structural framework. However, the tertiary structure and cystine-knot motif formed by the three disulfide bonds is similar to that present in several other polypeptide ion channel inhibitors. Conclusions: This is the first three-dimensional structure of a 'four-loop' sodium channel inhibitor, and it represents a valuable new structural probe for the pore region of voltage-dependent sodium channels. The distribution of amino acid sidechains in the structure creates several polar and charged patches, and comparison with the mu conotoxins provides a basis for determining the binding surface of the conotoxin GS polypeptide.

Increasing the Rates of Complete Response to Neoadjuvant Chemoradiotherapy for Distal Rectal Cancer: Results of a Prospective Study Using Additional Chemotherapy During the Resting Period

OBJECTIVES: Addition of chemotherapy in the resting period between radiotherapy completion and response assessment during neoadjuvant treatment for distal rectal cancer could potentially increase rates of complete tumor regression. The purpose of this study was to evaluate toxicity rates and the impact of an extended neoadjuvant chemoradiation regimen on complete response rates. METHODS: Thirty-four consecutive patients with nonmetastatic distal rectal cancer were prospectively included. Patients were managed by 5,400 Gy of radiation and 5-fluorouracil/leucovorin-based chemotherapy given for three consecutive days every 21 days for six cycles (three cycles concomitant with radiotherapy). Tumor response assessment was performed at ten weeks from radiation completion. Patients with complete clinical response were strictly monitored and were not immediately operated on. Patients with incomplete clinical response were referred to surgery. RESULTS: Twenty-nine patients had completed 12 months of follow-up and were included in this preliminary analysis. Twenty-eight (97%) successfully completed treatment. Fifteen of 16 patients had Grade III toxicities that were skin-related (93%). Median follow-up was 23 months. Fourteen patients (48%) were considered as complete clinical responders sustained for at least 12 months (median, 24 months) after chemoradiation completion by clinical assessment alone. An additional five patients (17%) were considered as complete responders with ypT0 results after full-thickness local excision. Overall, the complete response rate was 65%. CONCLUSIONS: The addition of chemotherapy during the resting period after neoadjuvant chemoradiation is associated with acceptable toxicity and high tolerability rates. The considerably high rates of complete response in this preliminary series requires further follow-up, but they may provide valuable information for future prospective, randomized trials.

The GHEP-EMPOP collaboration on mtDNA population data-A new resource for forensic casework

Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from Sao Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP-EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). (C) 2010 Elsevier Ireland Ltd. All rights reserved.