546 research outputs found
To fill or not to fill: a qualitative cross-country study on dentists' decisions in managing non-cavitated proximal caries lesions
BACKGROUND: This study aimed to identify barriers and enablers for dentists managing non-cavitated proximal caries lesions using non- or micro-invasive (NI/MI) approaches rather than invasive and restorative methods in New Zealand, Germany and the USA. METHODS: Semi-structured interviews were conducted, focusing on non-cavitated proximal caries lesions (radiographically confined to enamel or the outer dentine). Twelve dentists from New Zealand, 12 from Germany and 20 from the state of Michigan (USA) were interviewed. Convenience and snowball sampling were used for participant recruitment. A diverse sample of dentists was recruited. Interviews were conducted by telephone, using an interview schedule based on the Theoretical Domains Framework (TDF). RESULTS: The following barriers to managing lesions non- or micro-invasively were identified: patients' lacking adherence to oral hygiene instructions or high-caries risk, financial pressures and a lack of reimbursement for NI/MI, unsupportive colleagues and practice leaders, not undertaking professional development and basing treatment on what had been learned during training, and a sense of anticipated regret (anxiety about not restoring a proximal lesion in its early stages before it progressed). The following enablers were identified: the professional belief that remineralisation can occur in early non-cavitated proximal lesions and that these lesions can be arrested, the understanding that placing restorations weakens the tooth and inflicts a cycle of re-restoration, having up-to-date information and supportive colleagues and work environments, working as part of a team of competent and skilled dental practitioners who perform NI/MI (such as cleaning or scaling), having the necessary resources, undertaking ongoing professional development and continued education, maintaining membership of professional groups and a sense of professional and personal satisfaction from working in the patient's best interest. Financial aspects were more commonly mentioned by the German and American participants, while continuing education was more of a focus for the New Zealand participants. CONCLUSIONS: Decisions on managing non-cavitated proximal lesions were influenced by numerous factors, some of which could be targeted by interventions for implementing evidence-based management strategies in practice
Palatability and chemical defenses of sponges from the western Antarctic Peninsula
The present study surveyed the palatability of all sponge species that could be collected in sufficient quantities in a shallow-water area along the western Antarctic Peninsula. Of 27 species assayed, 78% had outermost tissues that were significantly unpalatable to the sympatric, omnivorous sea star Odontaster validus. Of those species with unpalatable outer tissues, 62% had inner tissues that were also unpalatable to the sea stars. Sea stars have often been considered as the primary predators of sponges in other regions of Antarctica, and their extra-oral mode of feeding threatens only the outermost sponge tissues. The observation that many of the sponges allocate defenses to inner tissues suggests the possibility that biting predators such as mesograzers, which could access inner sponge layers, may also be important in communities along the Antarctic Peninsula. In feeding bioassays with extracts from 12 of the unpalatable species in artificial foods, either lipophilic or hydrophilic extracts were deterrent in each species. These data indicate an overall level of chemical defenses in these Antarctic sponges that is comparable to, and slightly greater than, that found in a previous survey of tropical species
The new kid on the block: immigrant males win big whereas females pay fitness cost after dispersal
Dispersal is nearly universal; yet, which sex tends to disperse more and their success thereafter depends on the fitness consequences of dispersal. We asked if lifetime fitness differed between residents and immigrants (successful between‐population dispersers) and their offspring using 29 years of monitoring from North American red squirrels (Tamiasciurus hudsonicus) in Canada. Compared to residents, immigrant females had 23% lower lifetime breeding success (LBS), while immigrant males had 29% higher LBS. Male immigration and female residency were favoured. Offspring born to immigrants had 15–43% lower LBS than offspring born to residents. We conclude that immigration benefitted males, but not females, which appeared to be making the best of a bad lot. Our results are in line with male‐biased dispersal being driven by local mate competition and local resource enhancement, while the intergenerational cost to immigration is a new complication in explaining the drivers of sex‐biased dispersal.Our results are in line with male‐biased dispersal being driven by local mate competition and local resource enhancement, while the intergenerational cost to immigration is a new complication in explaining the drivers of sex‐biased dispersal.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154289/1/ele13436-sup-0001-Supinfo.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154289/2/ele13436.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154289/3/ele13436_am.pd
A bibliometric analysis of community dentistry and oral epidemiology: fifty years of publications
Objectives
In celebration of the journal's 50th anniversary, the aim of the study was to review the whole collection of Community Dentistry and Oral Epidemiology (CDOE) publications from 1973 to 2022 and provide a complete overview of the main publication characteristics.
Methods
The study used bibliometric techniques such as performance and science mapping analysis of 3428 articles extracted from the Scopus database. The data were analysed using the ‘Bibliometrix’ package in R. The journal's scientific production was examined, along with the yearly citation count, the distribution of publications based on authors, the corresponding author's country and affiliation and citation count, citing source and keywords. Bibliometric network maps were constructed to determine the conceptual, intellectual and social collaborative structure over the past 50 years. The trending research topics and themes were identified.
Results
The total number of articles and average citations has increased over the years. D Locker, AJ Spencer, A Sheiham and WM Thomson were the most frequently published authors, and PE Petersen, GD Slade and AI Ismail published papers with the highest citations. The most published countries were the United States, United Kingdom, Brazil and Canada, frequently engaging in collaborative efforts. The most common keywords used were ‘dental caries’, ‘oral epidemiology’ and ‘oral health’. The trending topics were healthcare and health disparities, social determinants of health, systematic review and health inequalities. Epidemiology, oral health and disparities were highly researched areas.
Conclusion
This bibliometric study reviews CDOE's significant contribution to dental public health by identifying key research trends, themes, influential authors and collaborations. The findings provide insights into the need to increase publications from developing countries, improve gender diversity in authorship and broaden the scope of research themes
Near-optimal mean value estimates for multidimensional Weyl sums
We obtain sharp estimates for multidimensional generalisations of
Vinogradov's mean value theorem for arbitrary translation-dilation invariant
systems, achieving constraints on the number of variables approaching those
conjectured to be the best possible. Several applications of our bounds are
discussed
Gender inequities in dental research publications: findings from 20 years
Background: The first steps towards gender equity in science are measuring the magnitude of inequity and increasing awareness of the problem. Objectives: To describe trends in gender disparities in first and last authorship in the most cited dental publications and general dental literature over a 20-year period. Methods: Articles and bibliometric data were retrieved from the Scopus database for the period 1996 to 2015. Two groups of 1000 articles each were retrieved: a random sample and another sample of top-cited articles for each year. The gender of the first and last author of each publication was manually identified. When this was not possible, we used an online software platform (https://genderize.io/). Descriptive analyses identified the proportion of women first and last authors in both samples, stratifying by dental discipline and geographic region. Trends were ascertained by frequency metrics across years. Gender disparity was observed in both first and last authorship, with a larger gap being observed in the top-cited sample. Results: Women led 28.4% and 20.3% of articles in the random and top-cited samples, respectively. A similar pattern was observed for the last authorship group (22.1% and 16.1%, respectively). An increasing trend in the proportion of articles led by women over time was observed in both samples. This increase was larger in the top-cited sample (from 15.0% in 1996–2000 to 25.1% in 2015) than in the random sample (from 26.3% in 1996–2000 to 33.2% in 2011). Conclusions: Clear gender disparities in dental research publications in the last 20 years were identified in both general and top-cited manuscripts, across dental disciplines, across countries, across first and last authorship, and over time. It is paramount that actions are taken to attract, retain and promote women in science, as well as to monitor and ensure progress towards gender equity
Psychometric assessment of the short-form Child Perceptions Questionnaire: an international collaborative study.
OBJECTIVE: To examine the factor structure and other psychometric characteristics of the most commonly used child oral-health-related quality-of-life (OHRQoL) measure (the 16-item short-form CPQ11-14 ) in a large number of children (N = 5804) from different settings and who had a range of caries experience and associated impacts. METHODS: Secondary data analyses used subnational epidemiological samples of 11- to 14-year-olds in Australia (N = 372), New Zealand (three samples: 352, 202, 429), Brunei (423), Cambodia (244), Hong Kong (542), Malaysia (439), Thailand (220, 325), England (88, 374), Germany (1055), Mexico (335) and Brazil (404). Confirmatory factor analysis (CFA) was used to examine the factor structure of the CPQ11-14 across the combined sample and within four regions (Australia/NZ, Asia, UK/Europe and Latin America). Item impact and internal reliability analysis were also conducted. RESULTS: Caries experience varied, with mean DMFT scores ranging from 0.5 in the Malaysian sample to 3.4 in one New Zealand sample. Even more variation was noted in the proportion reporting only fair or poor oral health; this was highest in the Cambodian and Mexican samples and lowest in the German sample and one New Zealand sample. One in 10 reported that their oral health had a marked impact on their life overall. The CFA across all samples revealed two factors with eigenvalues greater than 1. The first involved all items in the oral symptoms and functional limitations subscales; the second involved all emotional well-being and social well-being items. The first was designated the 'symptoms/function' subscale, and the second was designated the 'well-being' subscale. Cronbach's alpha scores were 0.72 and 0.84, respectively. The symptoms/function subscale contained more of the items with greater impact, with the item 'Food stuck in between your teeth' having greatest impact; in the well-being subscale, the 'Felt shy or embarrassed' item had the greatest impact. Repeating the analyses by world region gave similar findings. CONCLUSION: The CPQ11-14 performed well cross-sectionally in the largest analysis of the scale in the literature to date, with robust and mostly consistent psychometric characteristics, albeit with two underlying factors (rather than the originally hypothesized four-factor structure). It appears to be a sound, robust measure which should be useful for research, practice and policy
Social seed networks and climate change adaptation in East Africa
Our study investigates the routes of information flow through which smallholder exchange seed and information. We then examine how these exchanges among farmer networks can be improved. In order to examine the characteristics of these networks, our study analyzed household-level survey data collected by Bioversity International from sites in Kenya, Uganda, and Tanzania. Current seed sources and climate adaptation strategies were determined by creating summary statistics from the survey data. UCINET network analyses were conducted to acquire a more specific understanding of the current social networks among farmers. Seed networks were categorized by country, gender, and crop and then analyzed to determine where the distribution of seed and information can be improved and utilized
Palaeoproterozoic magnesite: lithological and isotopic evidence for playa/sabkha environments
Magnesite forms a series of 1- to 15-m-thick beds within the approximate to2.0 Ga (Palaeoproterozoic) Tulomozerskaya Formation, NW Fennoscandian Shield, Russia. Drillcore material together with natural exposures reveal that the 680-m-thick formation is composed of a stromatolite-dolomite-'red bed' sequence formed in a complex combination of shallow-marine and non-marine, evaporitic environments. Dolomite-collapse breccia, stromatolitic and micritic dolostones and sparry allochemical dolostones are the principal rocks hosting the magnesite beds. All dolomite lithologies are marked by delta C-13 values from +7.1 parts per thousand to +11.6 parts per thousand (V-PDB) and delta O-18 ranging from 17.4 parts per thousand to 26.3 parts per thousand (V-SMOW). Magnesite occurs in different forms: finely laminated micritic; stromatolitic magnesite; and structureless micritic, crystalline and coarsely crystalline magnesite. All varieties exhibit anomalously high delta C-13 values ranging from +9.0 parts per thousand to +11.6 parts per thousand and delta O-18 values of 20.0-25.7 parts per thousand. Laminated and structureless micritic magnesite forms as a secondary phase replacing dolomite during early diagenesis, and replaced dolomite before the major phase of burial. Crystalline and coarsely crystalline magnesite replacing micritic magnesite formed late in the diagenetic/metamorphic history. Magnesite apparently precipitated from sea water-derived brine, diluted by meteoric fluids. Magnesitization was accomplished under evaporitic conditions (sabkha to playa lake environment) proposed to be similar to the Coorong or Lake Walyungup coastal playa magnesite. Magnesite and host dolostones formed in evaporative and partly restricted environments; consequently, extremely high delta C-13 values reflect a combined contribution from both global and local carbon reservoirs. A C- 13-rich global carbon reservoir (delta C-13 at around +5 parts per thousand) is related to the perturbation of the carbon cycle at 2.0 Ga, whereas the local enhancement in C-13 (up to +12 parts per thousand) is associated with evaporative and restricted environments with high bioproductivity
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