929 research outputs found
Dentin Regeneration
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66570/2/10.1177_08959374950090030501.pd
A Potential Biofilm Metabolite Signature for Caries Activity - A Pilot Clinical Study
BACKGROUND: This study's aim was to compare the dental biofilm metabolite-profile of caries-active (N=11) or caries-free (N=4) children by gas chromatography-mass spectrometry (GC/MS) analyses.
METHODS: Samples collected after overnight fasting, with or without a previous glucose rinse, were combined for each child based on the caries status of the site, re-suspended in ethanol and analyzed by GC/MS.
RESULTS: Biofilm from caries-active sites exhibited a different chromatographic profile compared to caries-free sites. Qualitative and quantitative analysis suggested a special cluster of branched alcohols and esters present at substantially higher intensity in biofilms of caries-active sites.
CONCLUSIONS: This pilot study indicates that there are metabolites present in the biofilm which have the potential to provide a characteristic metabolomics signature for caries activity
Children living with ‘sustainable’ urban architectures
This paper considers the everyday geographies of children living in new large-scale urban developments in which multiple forms of ‘sustainable’ urban architecture are characteristic features. We argue that children’s experiences of living with materialities, politics and technologies of sustainability have too-often been marginalised in much chief research on childhood, youth and sustainability. Drawing on qualitative research with 8-16-year-olds living with materialities of ‘sustainable’ eco-housing, urban drainage, wind turbines and photovoltaic panelling, we explore how sustainable urban architectures are noticed, (mis)understood, cared about, and lived-with by children in the course of their everyday geographies. In so doing, we highlight the challenging prevalence and significance of architectural conservatisms, misconceptions, rumours disillusionments and urban myths relating to sustainable urban architectures
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
Combined search for the quarks of a sequential fourth generation
Results are presented from a search for a fourth generation of quarks
produced singly or in pairs in a data set corresponding to an integrated
luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in
2011. A novel strategy has been developed for a combined search for quarks of
the up and down type in decay channels with at least one isolated muon or
electron. Limits on the mass of the fourth-generation quarks and the relevant
Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a
simple extension of the standard model with a sequential fourth generation of
fermions. The existence of mass-degenerate fourth-generation quarks with masses
below 685 GeV is excluded at 95% confidence level for minimal off-diagonal
mixing between the third- and the fourth-generation quarks. With a mass
difference of 25 GeV between the quark masses, the obtained limit on the masses
of the fourth-generation quarks shifts by about +/- 20 GeV. These results
significantly reduce the allowed parameter space for a fourth generation of
fermions.Comment: Replaced with published version. Added journal reference and DO
Infants’ behavioral and physiological profile and mother–infant interaction
This study aims to (a) identify and profile groups of infants according to their behavioral and physiological characteristics, considering their neurobehavioral organization, social withdrawal behavior, and endocrine reactivity to stress, and to (b) analyze group differences in the quality of mother–infant interaction. Ninety seven 8-week-old infants were examined using the Neonatal Behavioral Assessment Scale and the Alarm Distress Baby Scale. Cortisol levels were measured both before and after routine inoculation between 8 and 12 weeks. At 12 to 16 weeks mother–infant interaction was assessed using the Global Rating Scales of Mother–Infant Interaction. Three groups of infants were identified: (a) ‘‘withdrawn’’; (b) ‘‘extroverted’’; (c) ‘‘underaroused.’’ Differences between them were found regarding both infant and mother behaviors in the interaction and the overall quality of mother–infant interaction. The identification of behavioral and physiological profiles in infants is an important step in the study of developmental pathways
Comparison of Cell Sediment and Surface Grown Test Plaque Using Scanning Electron Microscopy
Scanning electron microscopy was used to compare the morphology, integrity and distribution of bacterial cells in a test plaque grown on the surface of enamel with that of the cell sediment plaque routinely used in a short-term intraoral caries model. Cultures of S. mutans IB-1600 or S. sobrinus 6715-13 were grown in complex media supplemented with either 2.0% sucrose (glucan plaque) or 0.2 % glucose (non-glucan plaque). Cell sediment (CS) plaque was prepared by centrifuging the cultures after incubation, recovering the cell sediment, and spreading it on Metricel membrane filter paper. Surface grown (SG) plaque was prepared by suspending saliva-coated bovine enamel in the culture inedium, incubating, and recovering the enamel assembly with bacterial accumulations. Cell morphology and integrity, as well as the appearance of glucan-like material produced by the cells, was similar in both CS and SG test plaques. The cell distribution however, varied in the SG plaque from extremes of all cells to all glucan, whereas the cell sediment plaque was more uniform in cell distribution. A highly standardized test plaque minimizes variability in the intraoral caries model. These findings support the contention that the bacterial cells in a cell sediment plaque are similar in morphology, integrity and glucan production to surface grown plaque, and have the added advantage of uniform distribution, which makes the cell sediment plaque more appropriate for intraoral caries model studies
Randomised study of the effects of fluoride and time on in situ remineralisation of acid-softened enamel
Objectives
This single-centre, randomised, crossover study used a short-term in situ dental erosion remineralisation model to explore the remineralisation of acid-softened enamel in the 4-h period immediately following brushing with an anti-erosion, dentin hypersensitivity test dentifrice containing 1150 ppm fluoride (as sodium fluoride [NaF]) or a placebo dentifrice with no fluoride.
Materials and methods
Fifty participants wearing a palatal appliance holding surface-softened bovine enamel specimens brushed their natural teeth with their assigned dentifrice. Specimens were removed at 5-, 10-, 15-, 30-, 60-, 120- and 240-min post brushing. Enamel remineralisation effect was evaluated at each timepoint by percent surface microhardness recovery (%SMHR) and enamel fluoride uptake (EFU). After a second in vitro erosive challenge, the percent relative erosion resistance (%RER) was calculated.
Results
Statistically significant differences in %SMHR were observed for the test dentifrice compared with the placebo dentifrice from the 60-min timepoint onwards (all p < 0.02; mean difference of 8.66 [95% CI 3.46, 13.87] at 60 min). At each specimen removal time, %RER and EFU were statistically significantly higher for the test dentifrice compared with the placebo dentifrice (p < 0.0001 for all). No treatment-related or serious adverse events were reported.
Conclusions
The NaF-containing anti-erosion, dentin hypersensitivity dentifrice improved remineralisation of acid-softened enamel starting at 60 min of intra-oral exposure. It also improved enamel erosion resistance and fluoride uptake as early as 5 min after exposure to fluoridated dentifrice slurry
Особенности развития малого предпринимательства в Украине
В этой работе рассмотрена эволюция предпринимательства Украины на всех этапах ее общественной жизни, в том числе в период экономического кризиса в годы становления независимости. Отражены основные параметры отнесения предприятий к субъектам малого предпринимательства и их роль в развитии экономики государств.У цій роботі розглянута еволюція підприємництва України на всіх етапах її суспільного життя, зокрема в період економічної кризи в роки становлення незалежності. Відображені основні параметри віднесення підприємств до суб'єктів малого підприємництва і їх роль в розвитку економіки держав
The challenge of policy coordination for sustainable sociotechnical transitions: the case of the zero-carbon homes agenda in England
Emerging in recent research on sociotechnical transitions towards a low-carbon economy is the question of the extent to which such transitions require centralised, intentional coordination by government. Drawing from Hayek's conceptualisation of coordination, I evaluate the effectiveness of policy for low-carbon and zero-carbon homes in England. A detailed analysis is presented of how policy makers address complex choices and trade-offs as well as significant uncertainty. Particular attention is given to those policy decisions which are widely agreed by stakeholders to cause distortive effects. The focus here on the impacts of policy definition and delivery in terms of multiple evaluative criteria can complement and enrich the more process-orientated cross-sector and multilevel analyses that predominate in existing research on policy coordination. Furthermore, the coordination problems identified yield further insights into the actual and potential effectiveness of policy processes in shaping complex sociotechnical transitions
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