1,400 research outputs found
Assessment of the accuracy of 3D printed teeth by various 3D printers in forensic odontology
Additive manufacturing technology has benefited many sectors, and its use in forensic sciences has opened up a variety of new opportunities for analysing and exhibiting forensic materials. However, to perform analytical procedures on 3D printed bones and teeth in forensic odontology, the metric and morphological precision of the printed replicas must first be validated. To address this, the present study was undertaken using 12 extracted human teeth that were 3D printed using five different techniques. Manual measurements and a digital mesh comparison were used to evaluate the metric precision of all samples. The findings showed that the printed replicas were accurate to within 0.5 mm of the actual teeth. It was suggested that Digital Light Processing (DLP) prints be used for potential forensic odontology applications based on measurements, digital comparison, and ease of use
Trends of kidney cancer burden from 1990 to 2019 in European Union 15+ countries and World Health Organization regions
In recent decades, variability in the incidence and mortality of kidney cancer (KC) has been reported. This study aimed to compare trends in incidence, mortality, and disability-adjusted life years (DALY) of KC between the European Union (EU) 15 + countries and 6 World Health Organization (WHO) regions. The data of KC Age-standardized incidence rates (ASIRs), age-standardized mortality rates (ASMRs), and age-standardized DALYs were extracted from the Global Burden of Disease database. Joinpoint regression was employed to examine trends. From 1990 to 2019, the ASIR increased in most countries except for Luxembourg (males), the USA (females) and Austria and Sweden (both sexes). ASIR increased across all 6 WHO regions for both sexes except for females in Americas. The ASMR increased in 10/19 countries for males and 9/19 for females as well across most WHO regions. The mortality-to-incidence ratio (MIR) decreased in all countries and WHO regions. Trends in DALYs were variable across countries and WHO regions. While the incidence and mortality from KC rose in most EU15 + countries and WHO regions from 1990 to 2019, the universal drop in MIR suggests an overall improvement in KC outcomes. This is likely multifactorial, including earlier detection of KC and improved treatments
Flashlamp-pumped Ho:Tm:Cr:LuAG laser
A room temperature solid-state laser is provided. A laser crystal is disposed in a laser cavity. The laser crystal has a LuAG host material doped with a concentration of about 0.35% Ho ions, about 5.57% Tm ions and at least about 1.01% Cr ions. A broadband energizing source such as a flashlamp is disposed transversely to the laser crystal to energize the Ho ions, Tm ions and Cr ions
Diode-pumped Ho:Tm:YLF laser pumping and AgGaSe2 parametric oscillator
Tuning of both the pump laser, a Ho:Tm:YLF laser operating on the 5 I 7 - 5 I 8 transition, and an AgGaSe2 parametric oscillator has been demonstrated. Tuning of the Ho:Tm:YLF laser is complicated but not frustrated by the existence of both CO2 and H2O lines in the vicinity of the laser transition. Tuning of the parametric oscillator was achieved by tuning of the pump laser. Injection seeding of the parametric oscillator on the nonresonant signal was also demonstrated. In addition, the measured efficiencies of the parametric oscillator were compared by two different methods, measuring the parametric-oscillator output energy and measuring the energy depleted from the pump. By comparison of these measurements, the intrinsic efficiency of the parametric oscillator cab be determine
Enumeration of simple random walks and tridiagonal matrices
We present some old and new results in the enumeration of random walks in one
dimension, mostly developed in works of enumerative combinatorics. The relation
between the trace of the -th power of a tridiagonal matrix and the
enumeration of weighted paths of steps allows an easier combinatorial
enumeration of the paths. It also seems promising for the theory of tridiagonal
random matrices .Comment: several ref.and comments added, misprints correcte
Riparian zones increase regional species richness by harboring different, not more, species
Riparian zones are habitats of critical conservation concern worldwide, as they are known to filter agricultural contaminants, buffer landscapes against erosion, and provide habitat for high numbers of species. Here we test the generality of the notion that riparian habitats harbor more species than adjacent upland habitats. Using previously published data collected from seven continents and including taxa ranging from Antarctic soil invertebrates to tropical rain forest lianas and primates, we show that riparian habitats do not harbor higher numbers of species, but rather support significantly different species pools altogether. In this way, riparian habitats increase regional (γ-) richness across the globe by >50%, on average. Thus conservation planners can easily increase the number of species protected in a regional portfolio by simply including a river within terrestrial biodiversity reserves. Our analysis also suggests numerous possible improvements for future studies of species richness gradients across riparian and upland habitats. First, <15% of the studies in our analysis included estimates of more than one taxonomic group of interest. Second, within a given taxonomic group, studies employed variable methodologies and sampling areas in pursuit of richness and turnover estimates. Future analyses of species richness patterns in watersheds should aim to include a more comprehensive suite of taxonomic groups and should measure richness at multiple spatial scales
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