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IntroductionThis study was designed to assess whether a dental caries management protocol combining a single application of 38% silver diamine fluoride (SDF) with comprehensive oral health education will successfully divert high-risk children from dental treatment under dental general anaesthesia (DGA), arrest active caries in primary teeth, and improve parent-reported child oral health–related quality of life (OHRQoL).MethodsChildren aged 2 to 10 years, who attended two public dental agencies in Victoria, Australia, and were unable to tolerate restorative treatments in the clinic setting, elected to participate in either a 38% SDF intervention protocol or, alternatively, referral for DGA. Follow-up examinations were completed at 6 months to assess caries progression, decayed missing filled tooth index, PUFA index (pulpal involvement, ulceration, fistula, abscess), DGA referral rates, and OHRQoL (Early Childhood Oral Health Impact Scale [ECOHIS]).ResultsOf the total sample, 89.5% of children (n = 102) [mean (SD) age, 4.1 (1.0) years] with 401 active carious lesions elected to participate in the 38% SDF protocol; 10.5% (n = 12) of parents opted for referral for treatment under DGA. The proportion of active caries subsequently arrested at follow-up (number of arrested lesions/number of lesions treated) was 0.78 (95% CI, 0.69 to 0.87). There was an 88% reduction in referrals for DGA in eligible children over the 6-month period. The 38% SDF intervention group showed a significant improvement in ECOHIS scores at follow-up (P < .001).DiscussionAdoption of the 38% SDF intervention protocol resulted in a significant reduction in the rate of preventable dental hospitalisations. Most parents opted against referral for DGA. Parent-reported OHRQoL for children improved significantly.  相似文献   
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BackgroundPatients with a preoperative varus deformity >8 degrees are at increased risk of aseptic loosening after total knee arthroplasty. This study analyzes the effect of a tibial stem on the rate of aseptic loosening in patients with a severe preoperative varus deformity.MethodsPatients with a preoperative varus deformity of >8 degrees and 2-year minimum follow-up with a stemmed tibial component (n = 67) were matched 1:2 to patients with a similar preoperative varus deformity with a standard tibial component (n = 134). Radiolucent lines were measured on the tibia at 6 weeks, 1 year, and 2 years postoperatively using the Knee Society Radiographic Evaluation System. Failure was defined as revision due to aseptic loosening of the tibial component. Outcomes were evaluated using Student’s t-tests and log-rank tests.ResultsPatients with tibial stems had greater preoperative deformity (12.9 vs 11.3 degrees, P = .004). There was no difference in postoperative alignment (1.7 vs 2.1 degrees varus, P = .25) or tibial component angle (1.8 vs 2.1 degrees varus, P = .33). Patients with stems were more likely to have more constraint (44.8% vs 1.5%, P < .001). Progression of radiolucent lines >2 mm was observed in 17.6% (23/134) vs 5.97% (4/67) of patients in the stem group (P = .03). Rates of aseptic loosening were lower in the stem group (0% vs 5.15%, P = .05).ConclusionDespite worse preoperative deformity and higher utilization of constraint, tibial stem use in patients with severe preoperative varus deformity resulted in lower rates of aseptic loosening. Prophylactic use of stems in these patients may help increase implant survival.  相似文献   
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Exoplanet discovery has made remarkable progress, with the first rocky planets having been detected in the central star’s liquid water habitable zone. The remote sensing techniques used to characterize such planets for potential habitability and life rely solely on our understanding of life on Earth. The vegetation red edge from terrestrial land plants is often used as a direct signature of life, but it occupies only a small niche in the environmental parameter space that binds life on present-day Earth and has been widespread for only about 460 My. To more fully exploit the diversity of the one example of life known, we measured the spectral characteristics of 137 microorganisms containing a range of pigments, including ones isolated from Earth’s most extreme environments. Our database covers the visible and near-infrared to the short-wavelength infrared (0.35–2.5 µm) portions of the electromagnetic spectrum and is made freely available from biosignatures.astro.cornell.edu. Our results show how the reflectance properties are dominated by the absorption of light by pigments in the visible portion and by strong absorptions by the cellular water of hydration in the infrared (up to 2.5 µm) portion of the spectrum. Our spectral library provides a broader and more realistic guide based on Earth life for the search for surface features of extraterrestrial life. The library, when used as inputs for modeling disk-integrated spectra of exoplanets, in preparation for the next generation of space- and ground-based instruments, will increase the chances of detecting life.In the last decade, the field of exoplanet research has transitioned rapidly from detection to detection and characterization, with the first rocky exoplanets detected in the central star’s liquid water habitable zone. Much of the excitement of this research in both the astrobiology community and the general public is motivated by the quest to discover a second genesis of life. The great distances that separate us from even the most nearby stars dictate that all measurements of the exoplanet must be made through remote sensing techniques for the foreseeable future. Thus, it is critical for us to determine the types of biosignatures that we should be looking for when designing the next generation of ground- and space-based instruments that will observe these planets at high spectral and possibly spatial resolutions.Since the mid-1960s a primary life-searching strategy has been to look for a specific combination of an oxidizing and a reducing gas in the exoplanetary atmosphere, such as the O2 and CH4 in our atmosphere, because this is a thermodynamically unstable situation suggesting that an active agent such as life is responsible for the chemical disequilibrium (1, 2). Of particular interest, both from an observational and modeling perspective, is to complement those indirect life detection studies with surface features that are direct properties of the organisms themselves (3).Although there is a considerable knowledge base of the spectral properties of land plants (4, 5), very little information is present in the literature on the reflectance properties of microorganisms. Land plants are widespread on present-day Earth and are easily detected from high-resolution spacecraft observations (6). However, they occupy only a small niche in the environmental parameter space that brackets known terrestrial life. Additionally, land plants have been widespread on Earth for only about 460 My (7), whereas much of the history of life has been dominated by single-celled microbial life. Within the prokaryotic and eukaryotic microbes there is a far greater diversity of pigmentation than in land plants. For this reason, any hypotheses about extraterrestrial life based solely on land plants ignore much of the diversity of known life. To develop a more representative library of terrestrial spectra we produced a digital spectral library that provides high-resolution hemispherical reflectance measurements for 137 phylogenetically diverse microorganisms from the visible and near-infrared (VNIR, 0.35–1.0 µm) to the short-wavelength infrared (SWIR, 1.0–2.5 µm) regions of the electromagnetic spectrum. The library is made available from biosignatures.astro.cornell.edu.One approach when searching for life on exoplanets is to explore the range of pigmentation types that have evolved on this Earth. To examine the widest possible environmental range for life on Earth to inform our search we have chosen to include a diversity of extremophiles, organisms that live and thrive under conditions that make it challenging for a carbon-based organism using water as a solvent to survive (8). At the same time, we are cognizant of the fact that extremophiles are phylogenetically diverse and are unlikely to show spectral signatures not found among other pigmented organisms. Thus, we present reflectance spectra of organisms possessing a wide range of pigmentation but also complement this with the reflectance properties of various microorganisms that are isolated from some of Earth’s most extreme environments.The spectral features of surface life on exoplanets may depend on the local conditions that are prevalent on the planet. Organisms are only able to evolve in response to radiation that is present. However, the ability of life to respond to any wavelength is not limitless. Assuming that life is based on organic carbon and because such molecules have peak absorption in the UV portion of the spectrum, life is unlikely to use any but a small portion of UV A that are at the longer, less energetic wavelengths (9). Conversely, energy levels may be too low to be effective for biological processes much into the infrared regions of the spectrum. As such, it is unlikely that extraterrestrial surface life evolves its photosynthetic pigment too far in either direction of visible light. For these reasons, life on Earth primarily uses the 400- to 700-nm portion of the electromagnetic spectrum, and it is likely that organic carbon-based organisms that arose elsewhere would as well. The specific spectral signature within these confines may be either evolution-specific or depend on what radiation is available to these organisms. For example, land plants on Earth are green, but the poor use of green light is inefficiency that we might not see elsewhere. Organisms that use a light-gathering molecule for photosynthesis may evolve to have maximum absorption near the star’s spectral peak to take advantage of the freely available energy from the central star. The vegetation red edge, for instance, might be further in the infrared for photosynthetic organisms around M stars. However, any such hypotheses for life on potentially habitable exoplanets should consider the strong atmospheric and water absorptions that will attenuate most of the energy in the infrared regions of the electromagnetic spectrum and will thus not be readily available.The differences in the spectral characteristics between microorganisms is observed to be a result of the wavelength-dependent absorption by the pigmentation making up the organism and is independent of the functionality and hardiness that are often associated with extremophiles (10). Although pigments play an active role in screening UV radiation, oxidative damage prevention, and photosynthesis, they are often a result of secondary metabolic processes and are not primarily responsible for the hardiness of organisms to extreme environments (11, 12).The data presented in this work can be used as a reference for future disk-integrated observations of rocky exoplanets and serve as surface albedo input parameters to atmospheric radiative transfer models. Albedo is the directional integration of diffuse reflectance over all viewing angles and is therefore strongly dependent on the bidirectional reflectance distribution function (BRDF) of the sample material. For materials with large BRDF anisotropy, bidirectional reflectance measurements at a single viewing angle can often result in a poor approximation of the albedo. In addition, aside from the geometry differences, confounding effects of the atmosphere, stray light, multiple scattering due to the surroundings, and sample biomass have to be often accounted for in a bidirectional configuration, thereby creating several layers of complexities and uncertainties in the sample spectrum. We therefore focus on hemispherical reflectance measurements for all our sample organisms. The added advantage of this, besides severely reducing the confounding effects, is that one can approximate the surface to be Lambertian, as is commonly the case in exoplanetary atmospheric and climate models.  相似文献   
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Mycoplasmas possess complex pathogenicity determinants that are largely unknown at the molecular level. Mycoplasma agalactiae serves as a useful model to study the molecular basis of mycoplasma pathogenicity. The generation and in vivo screening of a transposon mutant library of M. agalactiae were employed to unravel its host colonization factors. Tn4001mod mutants were sequenced using a novel sequencing method, and functionally heterogeneous pools containing 15 to 19 selected mutants were screened simultaneously through two successive cycles of sheep intramammary infections. A PCR-based negative selection method was employed to identify mutants that failed to colonize the udders and draining lymph nodes in the animals. A total of 14 different mutants found to be absent from ≥95% of samples were identified and subsequently verified via a second round of stringent confirmatory screening where 100% absence was considered attenuation. Using this criterion, seven mutants with insertions in genes MAG1050, MAG2540, MAG3390, uhpT, eutD, adhT, and MAG4460 were not recovered from any of the infected animals. Among the attenuated mutants, many contain disruptions in hypothetical genes, implying their previously unknown role in M. agalactiae pathogenicity. These data indicate the putative role of functionally different genes, including hypothetical ones, in the pathogenesis of M. agalactiae. Defining the precise functions of the identified genes is anticipated to increase our understanding of M. agalactiae infections and to develop successful intervention strategies against it.  相似文献   
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The development and integration of electronic patient-reported outcomes (ePROs) into the radiation oncology clinic workflow provide novel opportunities, accompanied by unique design considerations and implementation challenges. The processes required for implementation of ePROs are entirely distinct from standard paper-based surveys, with the majority of time devoted to conception and design before initiating questionnaire build, detailed workflow process mapping including development of new workflows, comprehensive communication of the vision between providers and the information technology team, and quality assurance. Based on our experience with implementation of ePROs in our radiation oncology department, we developed a stepwise framework for approaching ePRO conceptual design, build, workflow integration, and the electronic health record interface. Here, we provide a guide for the numerous considerations, decision points, and solutions associated with the implementation of ePROs in the radiation oncology department setting. Although various ePRO tools and electronic health record capabilities impose different requirements, opportunities, and limitations, the conceptual processes and many of the electronic build considerations are broadly applicable.  相似文献   
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AimThe objective of this work was to determine the prevalence of early childhood caries (ECC) in children attending preschools that are enrolled in the Smiles 4 Miles health promotion program in Victoria and determine the sociodemographic variables associated with ECC.Materials and methodsA cross-sectional sample of 1,845 3- to 5-year-old children attending 61 preschools was selected by stratified cluster sampling. Dental caries was classified as non-cavitated/early lesions (d1-2), cavitated (d3-6) lesions, and cavitated/non-cavitated (d1-6) lesions using the International Caries Detection and Assessment System. A self-administered parental questionnaire captured sociodemographic and behavioural data. Multivariate logistic regression and Poisson mixed model analysis was used to examine associations amongst sociodemographic variables, child oral health behaviours, and decayed tooth surfaces.ResultsIn all, 56.6% (n = 1,044) of the children had ECC; more than one-third (36.6%) presented exclusively non-cavitated/early lesions, 5.7% solely cavitated lesions, and 14.2% both. Children from socioeconomically disadvantaged backgrounds had higher levels of dental caries. Parental pensioner/health care card status (incidence rate ratio [IRR] = 1.76, 95% CI, 1.57-1.97), non-English-speaking background (IRR = 2.09, 95% CI, 1.80-2.43), and Indigenous status (IRR = 1.91, 95% CI, 1.50-2.43) were associated with higher rates of cavitated lesions. Children who consumed soft drinks once or more per week had 1.66 times more cavitated lesions (95% CI, 1.48-1.86) compared to children who never/rarely consumed soft drinks. Soft drink consumption of once or more per week was associated with parental health care/pensioner card status (odds ratio [OR] = 1.73, 95% CI, 1.36-2.18), non-English-speaking background (OR = 1.58, 95% CI, 1.11-2.27), and Indigenous status (OR = 1.92, 95% CI, 1.04-3.52).ConclusionsHigher levels of more severe caries rates in children from socioeconomically disadvantaged background highlight an opportunity for early preventive interventions targeting these groups.  相似文献   
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