655 research outputs found
A comparison of four methods of dental age estimation and age estimation from the Risser sign of the iliac crest
Age estimation techniques are of medicolegal importance for estimating the age of living asylum seekers. as well as for unidentified human remains from forensic cases. As there are many techniques for age estimation, this study compares four different methods using dental radiographs of modern subadults (under 18 years) to determine which is more accurate for the modern sample. Additionally, this study explores age estimation from apophyseal fusion in the pelvis using the Risser method of the iliac crest compared to estimates of dental age. This study additionally compares the accuracy of four dental age estimation methods, including: Schour and Massler (1941), Schour and Massler (1944), Ubelaker (1989), and the London Atlas Method by AlQahtani et al. (2010). To determine the accuracy of the methods, this project correlates the actual age of modern individuals and the age estimated by each of the aforementioned methods. Overall it was found that Schour and Massler (1941), Schour and Massler (1944), and the London Atlas Method overestimated the age while the Ubelaker method slightly underestimated the age. All dental age estimation methods far exceed the accuracy of apophyseal fusion of the iliac crest using the Risser method
Analytical Solutions for Efficient Interpretation of Single-well Push-pull Tracer Tests
Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility of the solution for determining (1) estimates of aquifer longitudinal and transverse dispersivities, (2) sorption distribution coefficients and rate constants, and (3) non-aqueous phase liquid (NAPL) saturations. Employment of the solution to estimate NAPL saturations based on partitioning and non-partitioning tracers is designed to overcome limitations of previous efforts by including rate-limited mass transfer. This solution provides a new tool for use by practitioners when interpreting single-well push-pull test results
Two Algebraic Process Semantics for Contextual Nets
We show that the so-called 'Petri nets are monoids' approach initiated by Meseguer and Montanari can be extended from ordinary place/transition Petri nets to contextual nets by considering suitable non-free monoids of places. The algebraic characterizations of net concurrent computations we provide cover both the collective and the individual token philosophy, uniformly along the two interpretations, and coincide with the classical proposals for place/transition Petri nets in the absence of read-arcs
Modeling NAPL dissolution from pendular rings in idealized porous media
The dissolution rate of nonaqueous phase liquid (NAPL) often governs the remediation time frame at subsurface hazardous waste sites. Most formulations for estimating this rate are empirical and assume that the NAPL is the nonwetting fluid. However, field evidence suggests that some waste sites might be organic wet. Thus, formulations that assume the NAPL is nonwetting may be inappropriate for estimating the rates of NAPL dissolution. An exact solution to the YoungâLaplace equation, assuming NAPL resides as pendular rings around the contact points of porous media idealized as spherical particles in a hexagonal close packing arrangement, is presented in this work to provide a theoretical prediction for NAPLâwater interfacial area. This analytic expression for interfacial area is then coupled with an exact solution to the advectionâdiffusion equation in a capillary tube assuming HagenâPoiseuille flow to provide a theoretical means of calculating the mass transfer rate coefficient for dissolution at the NAPLâwater interface in an organicâwet system. A comparison of the predictions from this theoretical model with predictions from empirically derived formulations from the literature for waterâwet systems showed a consistent range of values for the mass transfer rate coefficient, despite the significant differences in model foundations (water wetting versus NAPL wetting, theoretical versus empirical). This finding implies that, under these system conditions, the important parameter is interfacial area, with a lesser role played by NAPL configuration.Key Points:Exact solution to the YoungâLaplace equation for pendular ringsTheoretical determination of the mass transfer rate coefficient under hydrophobic conditionsPredicts similar NAPL dissolution rates for oilâwet and waterâwet conditionsPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145506/1/wrcr21729.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145506/2/wrcr21729_am.pd
Modeling NAPL Dissolution from Pendular Rings in Idealized Porous Media
The dissolution rate of nonaqueous phase liquid (NAPL) often governs the remediation time frame at subsurface hazardous waste sites. Most formulations for estimating this rate are empirical and assume that the NAPL is the nonwetting fluid. However, field evidence suggests that some waste sites might be organic wet. Thus, formulations that assume the NAPL is nonwetting may be inappropriate for estimating the rates of NAPL dissolution. An exact solution to the YoungâLaplace equation, assuming NAPL resides as pendular rings around the contact points of porous media idealized as spherical particles in a hexagonal close packing arrangement, is presented in this work to provide a theoretical prediction for NAPLâwater interfacial area. This analytic expression for interfacial area is then coupled with an exact solution to the advectionâdiffusion equation in a capillary tube assuming HagenâPoiseuille flow to provide a theoretical means of calculating the mass transfer rate coefficient for dissolution at the NAPLâwater interface in an organicâwet system. A comparison of the predictions from this theoretical model with predictions from empirically derived formulations from the literature for waterâwet systems showed a consistent range of values for the mass transfer rate coefficient, despite the significant differences in model foundations (water wetting versus NAPL wetting, theoretical versus empirical). This finding implies that, under these system conditions, the important parameter is interfacial area, with a lesser role played by NAPL configuration. Abstract © AGU
Real-time earthquake hazard assessment in California; the early post-earthquake damage assessment tool and the Caltech-USGS broadcast of earthquakes
A real-time earthquake monitoring system which provides source parameters
to user groups through a commercial paging service is now in place in California.
A GIS-based system to predict and display near real-time damage and casualty
estimates is currently being developed by EQE International under contract with
the State of California. These new technologies offer immediate tangible benefits
to state and local governments, utilities, lifelines and corporations with facilities
or operations at risk. This paper will outline the development of these new
technologies, identify the contributions they will make to emergency management
and explore some directions these innovative systems may take in the future
Ferromagnetism and superconductivity in P-doped CeFeAsO
We report on superconductivity in CeFeAs1-xPxO and the possible coexistence
with Ce- ferromagnetism (FM) in a small homogeneity range around x = 30% with
ordering temperatures of T_SC = T_C = 4K. The antiferromagnetic (AFM) ordering
temperature of Fe at this critical concentration is suppressed to T^N_Fe ~ 40K
and does not shift to lower temperatures with further increase of the P
concentration. Therefore, a quantum-critical-point scenario with T^N_Fe -> 0K
which is widely discussed for the iron based superconductors can be excluded
for this alloy series. Surprisingly, thermal expansion and X-ray powder
diffraction indicate the absence of an orthorhombic distortion despite clear
evidence for short range AFM Fe-ordering from muon-spin-rotation measurements.
Furthermore, we discovered the formation of a sharp electron spin resonance
signal unambiguously connected with the emergence of FM ordering.Comment: 5 pages, 4 figures, published in Phys. Rev. B (Rapid Communication,
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Towards a Notion of Distributed Time for Petri Nets
We set the ground for research on a timed extension of Petri nets where time parameters are associated with tokens and arcs carry constraints that qualify the age of tokens required for enabling. The novelty is that, rather than a single global clock, we use a set of unrelated clocks --- possibly one per place --- allowing a local timing as well as distributed time synchronisation. We give a formal definition of the model and investigate properties of local versus global timing, including decidability issues and notions of processes of the respective models
No Influence of the Fat Mass and Obesity-Associated Gene rs9939609 Single Nucleotide Polymorphism on Blood Lipids in Young Males
The fat mass and obesity-associated gene (FTO) rs9939609 A-allele is linked to obesity and dyslipidemia, yet the independent influence of this polymorphism on blood lipids remains equivocal. We examined the influence of the FTO rs9939609 polymorphism on fasting and postprandial blood lipids in individuals homozygous for the risk A-allele or T-allele with similar anthropometric and demographic characteristics. 12 AA and 12 TT males consumed a standardized meal after fasting overnight. Blood samples were collected at baseline (â1.5 h), before the meal (0 h), and for five hours postprandially to measure lipid, glucose, and insulin concentrations. Time-averaged total area under the curve (TAUC) values (0â5 h) were calculated and compared between genotypes. Fasting triacylglycerol (TG), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol, non-esterified fatty acid (NEFA), glucose, and insulin concentrations were similar between groups (p â„ 0.293). TAUC for TG was similar in AAs and TTs (95% confidence interval (CI) â0.52 to 0.31 mmol/L/h; p = 0.606). Likewise, TAUC values were similar for NEFA (95% CI â0.04 to 0.03 mmol/L/h; p = 0.734), glucose (95% CI â0.41 to 0.44 mmol/L/h; p = 0.951), and insulin (95% CI â6.87 to 2.83 pmol/L/h; p = 0.395). Blood lipids are not influenced by the FTO rs9939609 polymorphism, suggesting the FTO-dyslipidemia link is mediated by adiposity and weight management is important in preventing FTO-related lipid variations
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