Aim
To assess the feasibility of producing artificial teeth for endodontic training using 3D printing technology, to analyse the accuracy of the printing process, and to evaluate the teeth by ...students when used during training.
Methodology
Sound extracted human teeth were selected, digitalized by cone beam computed tomography (CBCT) and appropriate software and finally reproduced by a stereolithographic printer. The printed teeth were scanned and compared with the original ones (trueness) and to one another (precision). Undergraduate dental students in the third and fourth years performed root canal treatment on printed molars and were subsequently asked to evaluate their experience with these compared to real teeth.
Results
The workflow was feasible for manufacturing 3D printed tooth replicas. The absolute deviation after printing (trueness) ranged from 50.9 to 104.3 μm. The values for precision ranged from 43.5 to 68.2 μm. Students reported great benefits in the use of the replicated teeth for training purposes.
Conclusion
The presented workflow is feasible for any dental educational institution who has access to a CBCT unit and a stereolithographic printer. The accuracy of the printing process is suitable for the production of tooth replicas for endodontic training. Undergraduate students favoured the availability of these replicas and the fairness they ensured in training due to standardization.
Data were obtained on the general population epidemiology of DSM-III-R posttraumatic stress disorder (PTSD), including information on estimated life-time prevalence, the kinds of traumas most often ...associated with PTSD, sociodemographic correlates, the comorbidity of PTSD with other lifetime psychiatric disorders, and the duration of an index episode.
Modified versions of the DSM-III-R PTSD module from the Diagnostic Interview Schedule and of the Composite International Diagnostic Interview were administered to a representative national sample of 5877 persons aged 15 to 54 years in the part II subsample of the National Comorbidity Survey.
The estimated lifetime prevalence of PTSD is 7.8%. Prevalence is elevated among women and the previously married. The traumas most commonly associated with PTSD are combat exposure and witnessing among men and rape and sexual molestation among women. Posttraumatic stress disorder is strongly comorbid with other lifetime DSM-III-R disorders. Survival analysis shows that more than one third of people with an index episode of PTSD fail to recover even after many years.
Posttraumatic stress disorder is more prevalent than previously believed, and is often persistent. Progress in estimating age-at-onset distributions, cohort effects, and the conditional probabilities of PTSD from different types of trauma will require future epidemiologic studies to assess PTSD for all lifetime traumas rather than for only a small number of retrospectively reported "most serious" traumas.
Measurements of the dark energy equation-of-state parameter, w, have been limited by uncertainty in the selection effects and photometric calibration of z < 0.1 Type Ia supernovae (SNe Ia). The ...Foundation Supernova Survey is designed to lower these uncertainties by creating a new sample of z < 0.1 SNe Ia observed on the Pan-STARRS system. Here we combine the Foundation sample with SNe from the Pan-STARRS Medium Deep Survey and measure cosmological parameters with 1338 SNe from a single telescope and a single, well-calibrated photometric system. For the first time, both the low-z and high-z data are predominantly discovered by surveys that do not target preselected galaxies, reducing selection bias uncertainties. The z > 0.1 data include 875 SNe without spectroscopic classifications, and we show that we can robustly marginalize over CC SN contamination. We measure Foundation Hubble residuals to be fainter than the preexisting low-z Hubble residuals by 0.046 0.027 mag (stat + sys). By combining the SN Ia data with cosmic microwave background constraints, we find w = −0.938 0.053, consistent with ΛCDM. With 463 spectroscopically classified SNe Ia alone, we measure w = −0.933 0.061. Using the more homogeneous and better-characterized Foundation sample gives a 55% reduction in the systematic uncertainty attributed to SN Ia sample selection biases. Although use of just a single photometric system at low and high redshift increases the impact of photometric calibration uncertainties in this analysis, previous low-z samples may have correlated calibration uncertainties that were neglected in past studies. The full Foundation sample will observe up to 800 SNe to anchor the LSST and WFIRST Hubble diagrams.
This study evaluated the impact of an integrated population health enhancement program on employee health risks, health conditions, and productivity. Specifically, we analyzed changes in these ...measures among a cohort of 543 employees who completed a health risk assessment in both 2003 and 2005. We compared these findings with 2 different sets of employees who were not offered health enhancement programming. We found that the DIRECTV cohort showed a significant reduction in health risks after exposure to the program. Relative to a matched comparison group, the proportion of low-risk employees at DIRECTV in 2005 was 8.2 percentage points higher; the proportion of medium-risk employees was 7.1 percentage points lower; and the proportion of high-risk employees was 1.1 percentage points lower (p < 0.001). The most noticeable changes in health risk were a reduction in the proportion of employees with high cholesterol; an improvement in diet; a reduction of heavy drinking; management of high blood pressure; improved stress management; increased exercise; fewer smokers; and a drop in obesity rates. We also found that a majority of employees who improved their risk levels from 2003 to 2005 maintained their gains in 2006. Employees who improved their risks levels also demonstrated relative improvement in absenteeism. Overall, this study provides additional evidence that integrated population health enhancement positively impacts employees' health risk and productivity; it also reinforces the view that "good health is good business".
The haematologist medical directors of the Hemophilia Region III Treatment Centers in the mid‐Atlantic Region III of the United States identified individuals in their databases diagnosed with ...additional congenital coagulopathies co‐expressing with Von Willebrand’s disease (VWD) and its variants. Sixteen individuals from 14 unrelated families, originating from five institutions, had been evaluated comprehensively. They represented approximately 1.5% of the calculated VWD population (n = 986) registered in region III at the end of year 2002. Eleven of the 16 (68.75%) had type 1 VWD; two (12.5%) had type 2A; two (12.5%) had type 2 Normandy (2N) and one (6.25%) had coexisting type 2B and type 2N VWD. The accompanying coagulopathies consisted of severe or moderate factor VIII (FVIII) deficiency (haemophilia A) in six (37.5%); severe or moderate factor IX deficiency (haemophilia B) in three (18.75%); severe or moderate factor XI deficiency in two (12.5%); severe factor VII deficiency in two (12.5%); combined factor XI and XII deficiencies in one (6.25%); qualitative platelet abnormality in one (6.25%); and one had combined type 2B and type 2N VWD (6.25%). The reversal of overt bleeding often required multiple therapeutic modalities, mandated by the specific combination of coagulation disorders. This included administration of specific purified clotting factor concentrates, cryoprecipitate, fresh frozen plasma, 1,8 deamino‐d‐arginine vasopressin, antifibrinolytic agents, platelet transfusions, etc. In summary, combined inherited coagulopathies coexisting with VWD are uncommon and frequently are phenotypically divergent from VWD. Successful therapy required an individualized approach, employing multiple replacement strategies, based on the laboratory definition of the specific additional coagulation defect.
Prevalences of Alcohol Use Disorders (AUDs) and Mental Health Disorders (MHDs) in many individual countries have been reported but there are few cross-national studies. The WHO World Mental Health ...(WMH) Survey Initiative standardizes methodological factors facilitating comparison of the prevalences and associated factors of AUDs in a large number of countries to identify differences and commonalities.
Lifetime and 12-month prevalence estimates of DSM-IV AUDs, MHDs, and associations were assessed in the 29 WMH surveys using the WHO CIDI 3.0.
Prevalence estimates of alcohol use and AUD across countries and WHO regions varied widely. Mean lifetime prevalence of alcohol use in all countries combined was 80%, ranging from 3.8% to 97.1%. Combined average population lifetime and 12-month prevalence of AUDs were 8.6% and 2.2% respectively and 10.7% and 4.4% among non-abstainers. Of individuals with a lifetime AUD, 43.9% had at least one lifetime MHD and 17.9% of respondents with a lifetime MHD had a lifetime AUD. For most comorbidity combinations, the MHD preceded the onset of the AUD. AUD prevalence was much higher for men than women. 15% of all lifetime AUD cases developed before age 18. Higher household income and being older at time of interview, married, and more educated, were associated with a lower risk for lifetime AUD and AUD persistence.
Prevalence of alcohol use and AUD is high overall, with large variation worldwide. The WMH surveys corroborate the wide geographic consistency of a number of well-documented clinical and epidemiological findings and patterns.
•Alcohol use and alcohol use disorder (AUD) prevalence rates varied across countries.•Mean lifetime prevalences were 80% for alcohol use and 8.6% for AUD.•Risk of AUD onset began in adolescence, with 15% of all cases developed by age 18.•Comorbidity was high, with other mental disorders most often preceding AUD onset.•Patterns of AUDs and correlates were consistent across counties.
On 14 August 2019, the LIGO and Virgo Collaborations detected gravitational waves from a black hole and a 2.6 solar mass compact object, possibly the first neutron star -- black hole (NSBH) merger. ...In search of an optical counterpart, the Dark Energy Survey (DES) obtained deep imaging of the entire 90 percent confidence level localization area with Blanco/DECam 0, 1, 2, 3, 6, and 16 nights after the merger. Objects with varying brightness were detected by the DES Pipeline and we systematically reduced the candidate counterparts through catalog matching, light curve properties, host-galaxy photometric redshifts, SOAR spectroscopic follow-up observations, and machine-learning-based photometric classification. All candidates were rejected as counterparts to the merger. To quantify the sensitivity of our search, we applied our selection criteria to full light curve simulations of supernovae and kilonovae as they would appear in the DECam observations. Since the source class of the merger was uncertain, we utilized an agnostic, three-component kilonova model based on tidally-disrupted NS ejecta properties to quantify our detection efficiency of a counterpart if the merger included a NS. We find that if a kilonova occurred during this merger, configurations where the ejected matter is greater than 0.07 solar masses, has lanthanide abundance less than \(10^{-8.56}\), and has a velocity between \(0.18c\) and \(0.21c\) are disfavored at the \(2\sigma\) level. Furthermore, we estimate that our background reduction methods are capable of associating gravitational wave signals with a detected electromagnetic counterpart at the \(4\sigma\) level in \(95\%\) of future follow-up observations.
We present a sample of 21 hydrogen-free superluminous supernovae (SLSNe-I), and one hydrogen-rich SLSN (SLSN-II) detected during the five-year Dark Energy Survey (DES). These SNe, located in the ...redshift range 0.220<z<1.998, represent the largest homogeneously-selected sample of SLSN events at high redshift. We present the observed g,r, i, z light curves for these SNe, which we interpolate using Gaussian Processes. The resulting light curves are analysed to determine the luminosity function of SLSN-I, and their evolutionary timescales. The DES SLSN-I sample significantly broadens the distribution of SLSN-I light curve properties when combined with existing samples from the literature. We fit a magnetar model to our SLSNe, and find that this model alone is unable to replicate the behaviour of many of the bolometric light curves. We search the DES SLSN-I light curves for the presence of initial peaks prior to the main light-curve peak. Using a shock breakout model, our Monte Carlo search finds that 3 of our 14 events with pre-max data display such initial peaks. However, 10 events show no evidence for such peaks, in some cases down to an absolute magnitude of <-16, suggesting that such features are not ubiquitous to all SLSN-I events. We also identify a red pre-peak feature within the light curve of one SLSN, which is comparable to that observed within SN2018bsz.
Nearly 9 million Americans live in extreme-poverty neighborhoods, places that also tend to be racially segregated and dangerous. Yet, the effects on the well-being of residents of moving out of such ...communities into less distressed areas remain uncertain. Using data from Moving to Opportunity, a unique randomized housing mobility experiment, we found that moving from a high-poverty to lower-poverty neighborhood leads to long-term (10- to 15-year) improvements in adult physical and mental health and subjective well-being, despite not affecting economic self-sufficiency. A 1—standard deviation decline in neighborhood poverty (13 percentage points) increases subjective well-being by an amount equal to the gap in subjective well-being between people whose annual incomes differ by $13,000—a large amount given that the average control group income is $20,000. Subjective well-being is more strongly affected by changes in neighborhood economic disadvantage than racial segregation, which is important because racial segregation has been declining since 1970, but income segregation has been increasing.
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