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Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are an emerging issue in wastewater treatment. High‐temperature thermal processes, incineration being time‐tested, offer the opportunity to destroy and change the composition of PFAS. The fate of PFAS has been documented through wastewater sludge incinerators, including a multiple hearth furnace (MHF) and a fluidized bed furnace (FBF). The dewatered wastewater sludge feedstock averaged 247‐ and 1280‐μmol targeted PFAS per sample run in MHF and FBF feed, respectively. Stack emissions (reportable for all targeted PFAS from MHF only) averaged 5% of that value with shorter alkyl chain compounds comprising the majority of the targeted PFAS. Wet scrubber water streams accumulated nonpolar fluorinated organics from the furnace exhaust with an average of 0.740‐ and 0.114‐mol Fˉ per sample run, for the MHF and FBF, respectively. Simple alkane PFAS measured at the stack represented 0.5%–4.5% of the total estimated facility greenhouse gas emissions. Practitioner Points: The MHF emitted six short chain PFAS from the stack, which were shorter alkyl chain compounds compared with sludge PFAS.The FBF did not consistently emit reportable PFAS from the stack, but contamination complicated the assessment.Five percent of the MHF sludge molar PFAS load was reported in the stack.MHF and FBF wet scrubber water streams accumulated nonpolar fluorinated organics from the furnace exhaust.Ultra‐short volatile alkane PFAS measured at the stack represented 0.5%–4.5% of the estimated facility greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Purpose: To determine if a virtual externship (VE) is beneficial to potential applicants regarding their perceived knowledge of a pediatric dentistry residency program. Secondarily, this study identified general program characteristics that influence resident ranking decisions. Methods: All applicants who applied to a pediatric dentistry residency program in the Southeast were invited to participate in a VE. Those who participated in the externship (n = 65) were asked to voluntarily complete Pre‐ and Post‐VE surveys. Participants were asked 22 questions about their level of knowledge of both tangible and intangible aspects of the program such as stipend, patient volume, faculty‐resident interaction, and resident comradery. Participants were also asked to rank 9 general characteristics that influence ranking decisions such as geography, cost to attend, and reputation of the program and were asked to rate their satisfaction with the VE. Post‐VE data were compared to pre‐VE data to determine level of knowledge gained via Wilcoxin matched pairs signed rank test (significance set at p < 0.05). Results: When comparing Pre‐ and Post‐VE ratings of level of knowledge about each category, all 22 categories assessed showed statistically significant mean differences indicating perceived knowledge gain with the most knowledge gained for "resident satisfaction in the program." Of the nine program characteristics, clinical experience was the most important factor to participants. Participants (100%) were satisfied with the VE experience and indicated the VE gave them the opportunity to get to know the program. Conclusions: A virtual externship is a satisfactory option for increasing applicant knowledge of the tangible and intangible aspects of a residency program. [ABSTRACT FROM AUTHOR]

Purpose/objectives: To survey potential applicants applying to advanced education in pediatric dental programs and evaluate their preparedness upon graduating from an accredited dental school. Methods: Attendees of a virtual externship of a University program were recruited to participate in a web‐based survey. The survey collected demographic data, current levels of confidence with various pediatric clinical procedures, predicted confidence with those procedures, and number of procedures completed. Chi‐Square and analysis of variance statistics were performed on resulting data to determine statistical significance. Results: Fifty‐three participants completed the survey in its entirety (n = 53). Most respondents reported adequate didactic training, mean score of 3.6 (range 0–5) and a moderate to high impact of coronavirus disease 2019 on their overall training with a mean score of 4.9 (range 0–10). Current dental students reported that they are "not confident at all" (<2.0) for 15/24 (63%) of the procedures. Graduates reported "somewhat confident" (<3.0) for 13/24 (54%) of the categories. Both students and graduates report the lowest levels of confidence for managing dental trauma, invasive treatment of young patients (<4 years of age), and patients with special healthcare needs. Dental students self‐reported the expectation to feel more confident throughout their matriculation; however, their clinical experience was still reported to be limited. Students did not report reaching the level of "confident" for 75% of the procedures. Conclusion: Dental students and recent dental graduates alike perceive themselves to be under prepared for practice and do not feel confident in performing pediatric dental procedures. This study can provide dental schools, program directors, recent graduates, and dental students with an understanding of areas where they are under prepared and could offer areas where curricula and clinical experiences could be updated or modified. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate depth of cure of an opaque sealant when light cured from increasing tip distances with high irradiance light‐emitting diode (LED) curing units. Methods: Ultraseal XT Plus opaque sealant was cured in a 2 × 2 × 5 mm covered slot mold using LEDs in high irradiance (VALO, SmartLite) or regular mode (Demi Ultra). Curing durations were 9, 15, and 20 seconds for the VALO, SmartLite, and Demi Ultra, respectively. The light tip was placed at three distances from the sealant surface (0, 3, and 5 mm; N = 10/group). Depth of cure was determined at the sealant surface and at 0.5 mm increments using Vicker's hardness (VHN). Results were statistically analyzed using two‐way ANOVA and multiple comparisons (α = 0.05). Results: Depth of cure was significantly affected by the LEDs and light tip distance. At 0.5 mm below the surface, most combinations resulted in hardness higher than 80% of the surface value, except for SmartLite at 3 and 5 mm tip distances and VALO at 5 mm tip distance. Regardless of the tip distance, VALO and Demi Ultra achieved similar VHN values through 1.5 mm depth. Conclusions: It is not likely that sealant is adequately cured with LEDs, even for those in high power mode, when the light tip is moved away from the surface due to lower radiant exposure. [ABSTRACT FROM AUTHOR]

The foundation of separation science is the division or deconvolution of a mixture into constituent parts. To do so greatly informs our understanding of complex systems. Equally important is consideration of the behavior of a mixture as a whole—to consider if the whole is the sum of the parts or if individual components interact synergistically or antagonistically when combined. Application of separation science has seldom assumed greater importance than in consideration of the controversy surrounding the traditional and emergent views of the complex chemical system of natural organic matter (NOM). Analyses of simulated and actual environmental water samples using noninvasive separation techniques including flow field‐flow fractionation (flow FFF), excitation–emission matrix (EEM) fluorescence spectroscopy with parallel factor (PARAFAC) analyses, and dynamic light scattering (DLS) are discussed. The data are used to explore whether a distinct chemical category of humic (diagenetic) substances exists in NOM; whether separation of organic matter into fulvic and humic extracts has relevant meaning translatable to actual environmental water samples; whether extraction procedures alter the chemistry of NOM extracts; and, if humic and fulvic acids exist, what physicochemical property or properties make humic substances unique among other forms of NOM. A fluorescence‐based nonoperational definition of humic substances is introduced. The underexplored role of supramolecular, self‐assembled aggregation is presented as a NOM conceptual model. Responses are provided to questions raised in the great NOM debate within a supramolecular context. Core Ideas: A new supramolecular conceptual model invokes strong near‐covalent hydrogen bonding.A nonoperational definition of diagenetic (humic) substances is proposed.Alkali extracts are valid, though imperfect, organic matter proxies.A mechanism for intrinsic chemical recalcitrance of natural organic matter exists.Protection is a "function" of the supramolecular "form." [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the effect of different types of instructional styles—traditional lecture with and without video examples and contemporary format that simulated a flipped classroom—on dental students' learning of behavior guidance techniques (BGTs) in pediatric dentistry. The study also sought to determine if students had an improved comfort level with BGTs with these instructional methods, if videos improved learning and comfort with BGTs, and if there were differences in outcomes by gender. All 96 second‐year dental students at one U.S. dental school were recruited to participate in the study in 2017. Students were randomly divided into three groups: contemporary instruction (CI), traditional instruction with video (TIV), and traditional instruction with no video (TI). CI students watched a 20‐minute mini‐lecture and were divided into discussion groups led by calibrated faculty members. TIV students received 50 minutes of traditional lecture with video examples. TI students received a traditional lecture with no video examples. All groups completed a questionnaire prior to and on completion of the course. The questionnaire assessed students' learning and perceptions of the learning experience. All students participated in the course and the assessments, for a 100% response rate. The students' post‐course scores improved for all teaching methods (TI>CI>TIV) with no significant differences among them. CI students rated comfort with BGTs and usefulness of videos higher than the other groups, but the difference was not statistically significant. Students rated their satisfaction with and usefulness of the course high for all groups (>3 on a four‐point scale). Learning style and comfort treating children were not statistically significant by gender. Overall, the students reported high satisfaction with all the teaching methods. Although the differences were not statistically significant, discussion groups were ranked highest in satisfaction and usefulness. [ABSTRACT FROM AUTHOR]

Background/aims: Prompt management of dental trauma in children affects outcomes, and multiple educational resources are available. The aim of this study was to compare subjects' accuracy in answering a survey about dental trauma management utilizing a poster and a mobile healthcare application and to determine user preference for mode of delivery of information.Materials and Methods: A survey was administered to parents of patients in two pediatric dental practices. Questions collected demographic information, frequency of internet use, and responses to questions regarding dental trauma management for two separate scenarios. Participants used both a poster and a mobile application, but were randomly assigned as to which tool was utilized first.Results: Eighty-nine surveys were usable. The majority of respondents were aged 36-45 years (50.6%), had education beyond high school (64%), and had private insurance (52.8%). Less-educated individuals were more likely to report searching the Internet (74%) compared to individuals with a graduate degree (57%) (P = 0.017). The majority of subjects answered trauma management questions correctly with both tools. However, for an avulsed permanent tooth, individuals receiving the mobile application were more likely to select: 'put the tooth back in place' (71.1%) compared to those utilizing the poster, who chose 'put the tooth in milk' (56.8%) (P = 0.004). Less-educated individuals were willing to pay more for the application (P = 0.015) and were more likely to report being interested in receiving dental information through mobile technology in the future (P = 0.006).Conclusions: Both a poster and a mobile healthcare application are effective in delivering dental trauma information. [ABSTRACT FROM AUTHOR]

Objective To examine whether panoramic radiograph-determined mandibular cortical thickness correlated with quantitative computed tomography-derived bone mineral density ( BMD) in survivors of childhood acute lymphoblastic leukemia ( ALL). Methods We identified patients treated for ALL at St. Jude Children's Research Hospital, seen in the After Completion of Therapy ( ACT) Clinic between January of 2006 and January of 2014 who had QCT-derived BMD and panoramic radiographs obtained within 1 month of each other. Panoramic radiographs were independently scored by a pediatric radiologist, two pediatric dentists, and a general dentist using the Klemetti technique. We used the Spearman's rank correlation test and the multivariate regression model to investigate the effect of evaluator experience on results. Results The study cohort comprised 181 patients with 320 paired studies: 112 (62%) male, 112 (71%) were white. Median age at ALL diagnosis was 6.4 (range, 0-18.8) years. Median age at study was 11.9 (range, 3.3 to 29.4) years. The median average BMD was 154.6 (range, 0.73-256) mg/cc; median QCT Z-score (age and gender adjusted) was −0.875 (range, −5.04 to 3.2). We found very weak association between panoramic radiograph score and both QCT- BMD average ( P = 0.53) and QCT Z-score ( P = 0.39). Results were not influenced by level of reader experience. Conclusions The Klemetti technique of estimating BMD does not predict BMD deficits in children and young adult survivors of ALL, regardless of reviewer expertise. Alternative methods are needed whereby dental healthcare providers can identify and refer patients at risk for BMD deficits for detailed assessment and intervention. [ABSTRACT FROM AUTHOR]

Objective To determine whether recommended short curing times of three high-power light emitting diode ( LED) curing lights are sufficient to polymerize sealant materials. Methods Opaque-unfilled sealant (Delton LC Opaque), opaque-filled sealant (UltraSeal XT plus), and clear-filled sealant (FluroShield) were light cured in a covered slot-mold using the manufacturers' shortest recommended curing times with three high-power LED lights (3-s VALO, 5-s Fusion, 10-s Smartlite). A 40-s cure with a quartz-tungsten halogen ( QTH) light was used as control. Vickers hardness was measured 24 h after curing at the sealant surface and through the depth (0.5 mm increments) ( N = 10). Results were analyzed with two-way anova (pair-wise multiple comparisons, significance level 0.05). Results The high-power LEDs did not cure the sealants as deep as the QTH. Delton LC Opaque showed the least depth of cure as hardness values beyond a depth of 0.5 mm were not measurable regardless of the curing light. Even for UltraSeal XT plus, when surface hardness was about the same with all lights, hardness decreased more rapidly with depth for the LEDs. FluroShield showed the slowest decline in hardness through the depth for all lights. Conclusions Manufacturers' recommendations for shortest possible curing time with high-power LEDs were not sufficient for adequate polymerization of the tested sealants. [ABSTRACT FROM AUTHOR]

Part I: Occurrence, Fate, and Transport (this literature review) compiles research from 2013 investigating emerging pollutants in wastewater and environmental waters and the sources of emerging pollutants. The paper summarizes important findings on environmental aquatic occurrence, persistence and transport of emerging pollutants in the environment, monitoring approaches, modeling, and regulatory discussions. The paper further mentions updates in our understanding of the toxicological impacts of these compounds where relevant specifically to wastewater. Finally, the paper speaks to the environmental sinks and degradation of pollutants. Part II: Treatment (the companion to this review) includes discussion of water and wastewater treatment technologies on emerging pollutants. [ABSTRACT FROM AUTHOR]

Part I: Occurrence, Fate, and Transport (this literature review) summarizes research appearing in 2012 on the occurrence of emerging pollutants in wastewater and environmental waters, sources of emerging pollutants, the fate and transport of emerging pollutants in the environment, monitoring approaches, modeling, and regulatory discussions. Toxicity studies are included where relevant specifically to wastewater. Part II: Treatment (the companion to this review) includes discussion of water and wastewater treatment technologies on emerging pollutants. [ABSTRACT FROM AUTHOR]

Part I: Occurrence, Fate, and Transport (this literature review) summarizes research appearing in 2011 on the occurrence of emerging pollutants in wastewater and environmental waters, sources of emerging pollutants, the fate and transport of emerging pollutants in the environment, monitoring approaches, modeling, and regulatory discussions. Toxicity studies are included where relevant specifically to wastewater. Part II: Treatment (the companion to this review) includes discussion of water and wastewater treatment technologies on emerging pollutants. [ABSTRACT FROM AUTHOR]

Water and wastewater quality research and management pertaining to emerging pollutants, chemical or biological, for which discussion of occurrence surveys, fate and transport investigations, treatment processes, modeling, and/or toxicity/risk assessment appearing in the peerreviewed literature during 2010, are presented. [ABSTRACT FROM AUTHOR]

Reports of water quality research and management pertaining to emerging pollutants, either chemical or biological, for which discussion of occurrence surveys, fate investigations, treatment methodologies, modeling, and/or toxicity/risk assessment appearing in the peer-reviewed literature during 2009, are presented. [ABSTRACT FROM AUTHOR]

Reports of water quality research and management pertaining to emerging pollutants, either chemical or biological, for which discussion of occurrence surveys, fate investigations, treatment methodologies, modeling, and/or toxicity/risk assessment appearing in the peer-reviewed literature during 2008, are presented. [ABSTRACT FROM AUTHOR]

Reports of water quality research and management pertaining to emerging pollutants, either chemical or biological, for which discussion of occurrence surveys, fate investigations, treatment methodologies, biological effects, and/or toxicity/risk assessment appeared in the peerreviewed literature during 2007, are presented. [ABSTRACT FROM AUTHOR]