The Reliability Of Facial Soft Tissue Landmarks With Photogrammetry

Introduction:With attention being given to the deleterious effects of radiation exposure from dental radiographs and inaccuracies in cephalometric soft tissue measurements, an alternative method of facial analysis with sufficiently reliable soft tissue landmarks should be developed. The goals of this study were threefold: (1) to define a new, low-cost method for capturing standardized frontal and sagittal facial images, (2) to determine on which photographic view that landmarks can be more reliably located, and (3) to determine which landmarks are appropriate for quantitative facial analysis. Materials and Methods:Simultaneous frontal and right sagittal facial images of 10 male and 10 female dental student subjects were captured using high-definition webcams as part of a low-cost set-up. Seventeen identical predefined facial soft tissue landmarks were located by 5 examiners on both types of images and were recorded as coordinate values. These coordinate values were used to calculate the best estimate of the true value for each landmark, mean deviation from this best estimate, and reliability in the X- and Y-axes using the Shrout-Fleiss intraclass correlation coefficient with corresponding 95% confidence intervals. Two examiners repeated the landmark location to evaluate intra-examiner reliability. Results:With a 95% confidence interval range of \u3e0.950, nose and mouth landmarks were among the most reliable landmarks on frontal and sagittal facial images. Converselyright soft tissue gonionwas one of the least reliable landmarks located in this study. In general, landmarks located by a single examiner showed greater reliability than when there were multiple examiners. Conclusions:This low-cost method yielded frontal and sagittal images sufficient for landmark identification. The magnitude of error varies between landmarks, is largest for poorly demarcated landmarks, and most had a non-circular envelope of error. Certain landmarks were more reliable on sagittal images and others were more reliable on frontal images. All landmarks had greater reliability and less mean deviation when located by a single examiner

Cutting Red Tape in Health Care: How Streamlining Billing Can Reduce California's Health Care Costs

Examines inefficiencies in the state's administrative systems and proposes streamlining key processes and integrating health information networks to cut costs and add value. Offers case profiles of networks in Utah and New England as best practices

How Third World rural households adapt to dietary energy stress

People can adjust to environmental changes by calling on a wide range of physical attributes, capabilities, and behaviors. For survival, probably the most important are those that make it possible to prevent serious imbalances between food energy needs and the amount of food that can be acquired at acceptable cost. Those who formulate food and agricultural policies need to know the scope, costs, and benefits of the more common adaptive strategies used by poor people, who are normally at greatest risk of energy stress. In particular, policymakers and analysts need to assess the scope and limits of adjustments by individuals or groups. When might adjustments fail to be biologically adaptive, that is, to reduce the risk that adverse effects of undernourishment will prevent individuals from contributing to the genetic inheritance of future generations? Even if adjustments are biologically adaptive, when are they likely to involve unacceptable suffering, damage to health, or social incapacity? In How Third World Households Adapt to Dietary Energy Stress: The Evidence and the Issues, IFPRI Food Policy Review 2, Philip Payne and Michael Lipton draw upon relevant literature from a range of subjects spanning the biological, behavioral, and social sciences and set out a conceptual framework to identify the current state of knowledge and the gaps in it.Malnutrition Developing countries. ,Adaptation (Physiology) Developing countries. ,

On the general position subset selection problem

Let $f(n,\ell)$ be the maximum integer such that every set of $n$ points in the plane with at most $\ell$ collinear contains a subset of $f(n,\ell)$ points with no three collinear. First we prove that if $\ell \leq O(\sqrt{n})$ then $f(n,\ell)\geq \Omega(\sqrt{\frac{n}{\ln \ell}})$. Second we prove that if $\ell \leq O(n^{(1-\epsilon)/2})$ then $f(n,\ell) \geq \Omega(\sqrt{n\log_\ell n})$, which implies all previously known lower bounds on $f(n,\ell)$ and improves them when $\ell$ is not fixed. A more general problem is to consider subsets with at most $k$ collinear points in a point set with at most $\ell$ collinear. We also prove analogous results in this setting

Williamsia faeni sp. nov., an actinomycete isolated from a hay meadow

The taxonomic status of an actinomycete isolated from soil collected from a hay meadow was determined using a polyphasic approach. The strain, designated N1350T, had morphological and chemotaxonomic properties consistent with its classification in the genus Williamsia and formed a distinct phyletic line within the clade comprising the type strains of species of the genus Williamsia in the 16S rRNA gene tree. Strain N1350T shared highest 16S rRNA gene sequence similarities with Williamsia marianensis MT8T (98.1 %) and Williamsia muralis MA140-96T (98.3 %). However, strain N1350T was readily distinguished from the type strains of Williamsia species using a combination of phenotypic properties. On the basis of these data, strain N1350T is considered to represent a novel species of the genus Williamsia. The name proposed for this taxon is Williamsia faeni sp. nov., with the type strain N1350T (=DSM 45372T =NCIMB 14575T =NRRL B-24794T)

Ramsey-type theorems for lines in 3-space

We prove geometric Ramsey-type statements on collections of lines in 3-space. These statements give guarantees on the size of a clique or an independent set in (hyper)graphs induced by incidence relations between lines, points, and reguli in 3-space. Among other things, we prove that: (1) The intersection graph of n lines in R^3 has a clique or independent set of size Omega(n^{1/3}). (2) Every set of n lines in R^3 has a subset of n^{1/2} lines that are all stabbed by one line, or a subset of Omega((n/log n)^{1/5}) such that no 6-subset is stabbed by one line. (3) Every set of n lines in general position in R^3 has a subset of Omega(n^{2/3}) lines that all lie on a regulus, or a subset of Omega(n^{1/3}) lines such that no 4-subset is contained in a regulus. The proofs of these statements all follow from geometric incidence bounds -- such as the Guth-Katz bound on point-line incidences in R^3 -- combined with Tur\'an-type results on independent sets in sparse graphs and hypergraphs. Although similar Ramsey-type statements can be proved using existing generic algebraic frameworks, the lower bounds we get are much larger than what can be obtained with these methods. The proofs directly yield polynomial-time algorithms for finding subsets of the claimed size.Comment: 18 pages including appendi

Which point sets admit a k-angulation?

For k >= 3, a k-angulation is a 2-connected plane graph in which every internal face is a k-gon. We say that a point set P admits a plane graph G if there is a straight-line drawing of G that maps V(G) onto P and has the same facial cycles and outer face as G. We investigate the conditions under which a point set P admits a k-angulation and find that, for sets containing at least 2k^2 points, the only obstructions are those that follow from Euler's formula.Comment: 13 pages, 7 figure