Die Spacer Thickness Reproduction for Central Incisor Crown Fabrication with Combined Computer-aided Design and 3D Printing Technology: An in vitro Study

Statement of problem The inability to control die spacer thickness has been reported. However, little information is available on the congruency between the computer-aided design parameters for die spacer thickness and the actual printout. Purpose The purpose of this study was to evaluate the accuracy and precision of the die spacer thickness achieved by combining computer-aided design and 3-dimensional printing technology. Material and Methods An ivorine maxillary central incisor was prepared for a ceramic crown. The prepared tooth was duplicated by using polyvinyl siloxane duplicating silicone, and 80 die-stone models were produced from Type IV dental stone. The dies were randomly divided into 5 groups with assigned die spacer thicknesses of 25 μm, 45 μm, 65 μm, 85 μm, and 105 μm (n=16). The printed resin copings, obtained from a printer (ProJet DP 3000; 3D Systems), were cemented onto their respective die-stone models with self-adhesive resin cement and stored at room temperature until sectioning into halves in a buccolingual direction. The internal gap was measured at 5 defined locations per side of the sectioned die. Images of the printed resin coping/die-stone model internal gap dimensions were obtained with an inverted bright field metallurgical microscope at ×100 magnification. The acquired digital image was calibrated, and measurements were made using image analysis software. Mixed models (α=.05) were used to evaluate accuracy. A false discovery rate at 5% was used to adjust for multiple testing. Coefficient of variation was used to determine the precision for each group and was evaluated statistically with the Wald test (α=.05). Results The accuracy, expressed in terms of the mean differences between the prescribed die spacer thickness and the measured internal gap (standard deviation), was 50 μm (11) for the 25 μm group simulated die spacer thickness, 30 μm (10) for the 45 μm group, 15 μm (14) for the 65 μm group, 3 μm (23) for the 85 μm group, and -10 μm (32) for the 105 μm group. The precision mean of the measurements, expressed as a coefficient of variation, ranged between 14% and 33% for the 5 groups. Conclusions For the accuracy evaluation, statistically significant differences were found for all the groups, except the group of 85 μm. For the precision assessment, the coefficient of variation was above 10% for all groups, showing the printer’s inability to reproduce the uniform internal gap within the same group

Accuracy and Precision of Die Spacer Thickness with Combined Computer-Aided Design and 3-D Printing Technology

Purpose: The purpose of this study was to evaluate the accuracy and precision of die-spacer thickness achieved by the combination of computer aided design and 3-dimension printing technology. Materials and Methods: An ivorine maxillary central incisor was prepared for an all ceramic crown. The prepared tooth was duplicated by using poly (vinyl siloxane) duplicating silicone and 80 die-stone models were produced using type IV dental stone. Dies were randomly divided into 5 groups with assigned die spacer thickness of (25 μm, 45 μm, 65 μm, 85 μm, 105 μm) (n=16/group). The printed resin copings, obtained from 3D Systems ProJet DP 3000 printer, were cemented onto their respective die-stone models with Relyx Unicem 2 and stored at room temperature until sectioning into two halves, in the bucco-lingual direction. The internal gap was measured at 5 defined locations per side of the sectioned die: (A) facial chamfer, (B) facial mid-axial, (C) incisal, (D) lingual mid-axial, and lingual (E) chamfer. Images of the printed resin coping/die-stone model internal gap dimension were obtained with an inverted bright field metallurgical microscope at 100x magnification. The acquired digital image was calibrated and measurements were made using image analysis software. The results were compared using the mixed models ANOVA with repeated measurements to analyze the paired data and the level of significance was set at .05. The coefficients of variation (CV) were obtained by standard deviation divided by the mean and multiplied by 100. Results: The accuracy expressed in term of mean differences between prescribed die spacer thickness and measured internal gap width (standard deviation) were 50 μm (10) for the 25 μm group simulated die-spacer thickness, 30 μm (11) for the 45 μm group, 15 μm (14) for the 65 μm group, 3 μm (24) for the 85 μm group, and - 10 μm (32) for the 105 μm group. The precision mean of the measurements, expressed in percentages, ranged between 14 - 33% per the groups. Conclusions: The accuracy of die spacer thickness showed statistically significant difference for all the groups. The precision of the all groups was above 10% of CV

Implantation of a three-dimensional fibroblast matrix improves left ventricular function and blood flow after acute myocardial infarction

This study was designed to determine if a viable biodegradable three-dimensional fibroblast construct (3DFC) patch implanted on the left ventricle after myocardial infarction (MI) improves left ventricular (LV) function and blood flow. We ligated the left coronary artery of adult male Sprague-Dawley rats and implanted the 3DFC at the time of the infarct. Three weeks after MI, the 3DFC improved LV systolic function by increasing (p < 0.05) ejection fraction (37 +/- 3% to 62 +/- 5%), increasing regional systolic displacement of the infarcted wall (0.04 +/- 0.02 to 0.11 +/- 0.03 cm), and shifting the passive LV diastolic pressure volume relationship toward the pressure axis. The 3FDC improved LV remodeling by decreasing (p < 0.05) LV end-systolic and end-diastolic diameters with no change in LV systolic pressure. The 3DFC did not change LV end-diastolic pressure (LV EDP; 25 +/- 2 vs. 23 +/- 2 mmHg) but the addition of captopril (2mg/L drinking water) lowered (p < 0.05) LV EDP to 12.9 +/- 2.5 mmHg and shifted the pressure-volume relationship toward the pressure axis and decreased (p < 0.05) the LV operating end-diastolic volume from 0.49 +/- 0.02 to 0.34 +/- 0.03 ml. The 3DFC increased myocardial blood flow to the infarcted anterior wall after MI over threefold (p < 0.05). This biodegradable 3DFC patch improves LV function and myocardial blood flow 3 weeks after MI. This is a potentially new approach to cell-based therapy for heart failure after MI

Search for gravitational wave bursts in LIGO's third science run

We report on a search for gravitational wave bursts in data from the three LIGO interferometric detectors during their third science run. The search targets subsecond bursts in the frequency range 100-1100 Hz for which no waveform model is assumed, and has a sensitivity in terms of the root-sum-square (rss) strain amplitude of hrss ~ 10^{-20} / sqrt(Hz). No gravitational wave signals were detected in the 8 days of analyzed data.Comment: 12 pages, 6 figures. Amaldi-6 conference proceedings to be published in Classical and Quantum Gravit

Examination of Social Justice Behaviors: Testing an Integrated Model

In this study, we tested an integrated model of social justice behaviors among a community sample of 179 Asian American and White American adults. The integrated model builds on the theory of planned behavior (TPB) and sociopolitical development theory (SPD). Findings from path analyses provided partial support for the integrated model. Specifically, social justice awareness, subjective norms, and perceived behavioral control were uniquely and positively related to participants’ social justice intention. Intention to act, however, did not predict self-reported social justice behaviors. Multiple group comparison analyses suggested that the aspects of the integrated model consistent with the TPB were better supported in the White American sample, whereas the aspects of the model consistent with SPD were a better fit for the Asian American sample. Particularly, social justice attitudes were related to self-reported actions for Asian Americans in the sample, but not White Americans

An overview of outputs of Aboriginal- and Torres Strait Islander-related publications from University Departments of Rural Health in Australia; 2010–2021

Introduction Disparities in the health of Indigenous people and in the health of rural populations are well described. University Departments of Rural Health (UDRHs) in Australia are federally funded under a program to address ongoing challenges with health workforce distribution for rural and remote areas. They have a significant role in research in regional, rural and remote areas, including research related to Indigenous health. However, a comprehensive analysis of their contributions to original Indigenous health related to Indigenous health is lacking. Objective This study examines the contributions of UDRHs to Indigenous issues through analysis of publications of UDRHs focused on Indigenous health during the period 2010–2021. Design This paper examines a database of UDRH Indigenous-related publications from 2010 to 2021. Findings A total of 493 publications to which UDRHs contributed were analysed, including 354 original research articles. Health services research was the most common category, followed by epidemiology and papers exploring Indigenous culture and health. While health services research substantially increased over the period, the numbers of original research papers specifically focused on Indigenous workforce issues, whether related to Indigenous people, students or existing workforce was relatively small. Discussion This broad overview shows the nature and trends in Indigenous health research by UDRHs and makes evident a substantial contribution to Indigenous health research, reflecting their commitment to improving the health and well-being of Indigenous communities. Conclusions The analysis can help direct future efforts, and future analyses should delve deeper into the impact of this research and further engage Indigenous researchers

Do food quality schemes and net price premiums go together?

This article addresses the issue of the profitability of Food Quality Scheme (FQS) products as compared to reference products, which are defined as analogous products without quality label. We approach this question by taking into account the level of the value chain (upstream, processing, and downstream), the sector (vegetal, animal, seafood) and the type of FQS (PGI, PDO, Organic). We collected original data for several products produced in selected European countries, as well as in Thailand and Vietnam. Comparisons depending on value chain level, sector and FQS are possible by using two comparable indicators: price premium and net price premium (including cost differential). The following principal conclusions were reached: 1) Price is higher for FQS products than for the reference products, regardless of the production level, the type of FQS or the sector; 2) Price premiums generated by FQS do not differ along the value chain, nor between sectors (vegetal, animal or seafood/fish); 3) Price premium for organic products is significantly higher than for PGI products, and this conclusion holds at upstream and processing levels, taking into account the costs directly related to production; 4) All organic products and almost all PDO and PGI products analysed benefit from a positive quality rent; 5) At upstream level and processing level, the relative weight of intermediate consumption in the cost structure is lower for organic products than for reference products.Objectius de Desenvolupament Sostenible::12 - Producció i Consum ResponsablesPostprint (published version

Association of genetic variation with systolic and diastolic blood pressure among African Americans: the Candidate Gene Association Resource study

The prevalence of hypertension in African Americans (AAs) is higher than in other US groups; yet, few have performed genome-wide association studies (GWASs) in AA. Among people of European descent, GWASs have identified genetic variants at 13 loci that are associated with blood pressure. It is unknown if these variants confer susceptibility in people of African ancestry. Here, we examined genome-wide and candidate gene associations with systolic blood pressure (SBP) and diastolic blood pressure (DBP) using the Candidate Gene Association Resource (CARe) consortium consisting of 8591 AAs. Genotypes included genome-wide single-nucleotide polymorphism (SNP) data utilizing the Affymetrix 6.0 array with imputation to 2.5 million HapMap SNPs and candidate gene SNP data utilizing a 50K cardiovascular gene-centric array (ITMAT-Broad-CARe [IBC] array). For Affymetrix data, the strongest signal for DBP was rs10474346 (P= 3.6 × 10−8) located near GPR98 and ARRDC3. For SBP, the strongest signal was rs2258119 in C21orf91 (P= 4.7 × 10−8). The top IBC association for SBP was rs2012318 (P= 6.4 × 10−6) near SLC25A42 and for DBP was rs2523586 (P= 1.3 × 10−6) near HLA-B. None of the top variants replicated in additional AA (n = 11 882) or European-American (n = 69 899) cohorts. We replicated previously reported European-American blood pressure SNPs in our AA samples (SH2B3, P= 0.009; TBX3-TBX5, P= 0.03; and CSK-ULK3, P= 0.0004). These genetic loci represent the best evidence of genetic influences on SBP and DBP in AAs to date. More broadly, this work supports that notion that blood pressure among AAs is a trait with genetic underpinnings but also with significant complexit

Visualization of Partial Exocytotic Content Release and Chemical Transport into Nanovesicles in Cells

For decades, "all-or-none"and "kiss-and-run"were thought to be the only major exocytotic release modes in cell-to-cell communication, while the significance of partial release has not yet been widely recognized and accepted owing to the lack of direct evidence for exocytotic partial release. Correlative imaging with transmission electron microscopy and NanoSIMS imaging and a dual stable isotope labeling approach was used to study the cargo status of vesicles before and after exocytosis; demonstrating a measurable loss of transmitter in individual vesicles following stimulation due to partial release. Model secretory cells were incubated with 13C-labeled l-3,4-dihydroxyphenylalanine, resulting in the loading of 13C-labeled dopamine into their vesicles. A second label, di-N-desethylamiodarone, having the stable isotope 127I, was introduced during stimulation. A significant drop in the level of 13C-labeled dopamine and a reduction in vesicle size, with an increasing level of 127I-, was observed in vesicles of stimulated cells. Colocalization of 13C and 127I- in several vesicles was observed after stimulation. Thus, chemical visualization shows transient opening of vesicles to the exterior of the cell without full release the dopamine cargo. We present a direct calculation for the fraction of neurotransmitter release from combined imaging data. The average vesicular release is 60% of the total catecholamine. An important observation is that extracellular molecules can be introduced to cells during the partial exocytotic release process. This nonendocytic transport process appears to be a general route of entry that might be exploited pharmacologically

QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe