208 research outputs found
Dry bone and virtual modality interchangeability for the estimation of sex on the human pelvis and skull
Background: Traditional osteological methods are typically based on visual and tactile observational approaches. However, the tactile sensation is excluded when investigating skeletal remains in virtual reality. This raises the question of the actual comparability of data obtained from osteological analysis on analogous versus virtual modality. The aim of this work is to address this topic and quantify the deviation between the scoring on dry bone and virtual models of sexually dimorphic features on the human pelvis and skull.
Materials and methods: We applied seven widely used sex estimation methods to 200 archaeological pelves and 223 skulls. We scored and measured each method-specific trait on dry bone and computed tomographic (CT) models of the same individual. We added observations on 3D surface scans from sample subsets of pelves (N=39) and skulls (=50) for comparability. We compared the scores and measurements obtained from the application of each method to the three sets of observations using Cohen's Îş tests and relative technical error of measurement (rTEM).
Results: 1) metric traits are more repeatable and consistent than nonmetric traits; b) virtual modalities compared better to each other than visual-tactile modalities and c) precise trait descriptions are more important than the modality.
Discussion: Our data suggest that traditional sex estimation methods developed on dry bone (visual-tactile sensations) can be applied interchangeably to virtual specimens (visual-only sensation) without obtaining substantially different information. More than other factors, however, precise trait definition is pivotal for the interchangeability of analogous and virtual modalities
Environmental Fate of Chiral Pollutants – the Necessity of Considering Stereochemistry
Many organic compounds regulated by environmental laws are chiral and are released into the environment as racemates. 3-Phenylbutanoic acid and mecoprop, two chiral pollutants, were enantioselectively degraded by pure cultures of microorganisms. This indicates the importance of assessing the environmental impact of stereoisomers separately, because selective enrichment of one of the enantiomers may occur in the environment. Field studies on the fate of highly polar, chiral compounds, like sulfophenylcarboxylates, are hampered by the lack of appropriate analytical methods for the separation of the enantiomers. Therefore, a method based on capillary electrophoresis with α-cyclodextrin as chiral selector was developed to separate the enantiomers of such compounds. In a field study at a Swiss waste disposal site, the fate of the chiral herbicide mecoprop was investigated. The enantiomeric ratio of (R)-mecoprop to (S)-mecoprop altered during groundwater passage of landfill leachate. This is a strong indication for in situ biodegradation. Our data imply that not only the enantiomers of a chiral drug or pesticide may exert different effects on the biological targets, but also their biodegradation and environmental fate may differ
Incidence of delayed and missed diagnoses in whole-body multidetector CT in patients with multiple injuries after trauma
Background: Whole-body CT (WBCT) is the imaging modality of choice during the initial diagnostic work-up of multiple injured patients in order to identify serious injuries and initiate adequate treatment immediately. However, delayed diagnosed or even missed injuries have been reported frequently ranging from 1.3% to 47%. Purpose: To highlight commonly missed lesions in WBCT of patients with multiple injuries. Material and Methods: A total of 375 patients (age 42.8 +/- 17.9 years, ISS 26.6 +/- 17.0) with a WBCT (head to symphysis) were included. The final CT report was compared with clinical and operation reports. Discrepant findings were recorded and grouped as relevant and non-relevant to further treatment. In both groups, an experienced trauma radiologist read the CT images retrospectively, whether these lesions were missed or truly not detectable. Results: In 336 patients (89.6%), all injuries in the regions examined were diagnosed correctly in the final reports of the initial CT. Forty-eight patients (12.8%) had injuries in regions of the body that were not included in the CT. Fourteen patients (3.7%) had injuries that did not require further treatment. Twenty-five patients (6.7%) had injuries that required further treatment. With secondary interpretation, 85.4% of all missed lesions could be diagnosed in retrospect from the primary CT data-set. Small pancreatic and bowel contusions were identified as truly non-detectable. Conclusion: In multiple traumas, only a few missed injuries in initial WBCT reading are clinically relevant. However, as the vast majority of these injuries are detectable, the radiologist has to be alert for commonly missed findings to avoid a delayed diagnosis
Cryobiopsy increases the EGFR detection rate in non-small cell lung cancer
Objectives: Detection of activating epidermal growth factor receptor (EGFR) mutation is crucial for individualized treatment of advanced non-small-cell lung cancer (NSCLC). However little is known about how biopsy technique affects the detection rate of EGFR mutations. This retrospective, single center study evaluated the detection rate of EGFR mutations in tissue obtained by bronchoscopic cryobiopsy and compared this to other standard tissue sampling techniques. Materials and methods: We retrospectively analyzed 414 patients with histologically confirmed NSCLC and known EGFR mutation status between 3/2008-7/2014. Tumor specimens obtained by tissue preserving bronchoscopic cryobiopsy were compared to those obtained by other techniques. Results and conclusion: Analysis of bronchoscopic cryobiopsy tissue detected 29 activating EGFR mutations in 27 (21.6 ) out of 125 patients, while analysis of tissue obtained by non-cryobiopsy techniques (bronchoscopic forceps biopsies, fine needle aspiration, imaging guided transthoracical and surgical procedures) detected 42 EGFR mutations in 40 (13.8 ) out of 298 patients (p < 0.05). Cryobiopsy increased detection rate of EGFR mutations in central tumors compared with forceps biopsy (19.6 versus 6.5 , p < 0.05), while an insignificant trend was detected also for peripheral tumors (33.3 versus 26.9 ). Bronchosopic cryobiopsy increases the detection rate of activating EGFR mutations in NSCLC in comparison to other tissue sampling techniques. This will help to optimize individualized treatment of patients with advanced tumors. Because of the retrospective nature of this analysis, a prospective trial is mandatory for final assessment. © 2020 The Author(s
Quantum stereodynamics of Li + HF reactive collisions: The role of reactants polarization on the differential cross section
A complete quantum study for the state-to-state Li + HF(v,j,m) → LiF(v′,j′,Ω′) + H reactive collisions has been performed using a wave packet method, for different initial rotational states and helicity states of the reactants. The state-to-state differential cross section has been simulated, and the polarization of products extracted. It is found that the reactivity is enhanced for nearly collinear collisions, which produces a vibrational excitation of HF, needed to overcome the late barrier. It is also found that LiF(v′ = 0) products are preferentially forward scattered, while vibrationally excited LiF(v′ = 1 and 2) are backward scattered. These results are interpreted with a simple reaction mechanism, based on the late character and bent geometry of the transition state, originating from a covalent/ionic crossing, which consists of two steps: the arrival at the transition state and the dissociation. In the first step, in order to get to the saddle point some HF vibrational excitation is required, which favors head-on collisions and therefore low values of m. In the second step a fast dissociation of H atom takes place, which is explained by the ionic Li+F -H character of the bent transition state: the FH- is repulsive making that H depart rapidly leaving a highly rotating LiF molecule. For the higher energy analyzed, where resonances slightly contribute, the orientation and alignment of product rotational states, referred to as reactants frame (with the z-axis parallel to k), are approximately constant with the scattering angle. The alignment is close to -1, showing that j′ is perpendicular to k, while starting from initial states with well defined rotational orientation, as states with pure m values, the final rotational are also oriented. It is also found that when using products frame (with the z′-axis parallel to k′) the rotational alignment and orientation of products varies a lot with the scattering angle just because the z′ axis changes from being parallel to anti-parallel to k when varying from θ = 0 to π. © the Owner Societies 2011.This work has been supported by the Ministerio de Ciencia e Innovación, under grants CSD2009-00038 (programa CONSOLIDER-INGENIO 2010 entitled “Molecular Astrophysics: the Herschel and Alma era”), FIS2010-18132, CTQ2008-02578 and CTQ2007-62898, and by Comunidad Autónoma de Madrid (CAM) under Grant No. S-0505/MAT/0303.Peer Reviewe
Unguis incarnatus – konservative oder operative Therapie?
Unguis incarnatus, an ingrown toenail, is a common condition in primary care, which is encountered by various medical professions. Inconsistent conservative treatment and nonindicated surgical treatment often result in complications and recurrence of the disease. Patients must be thoroughly informed about the complexity of the nail organ. This is a prerequisite to prevent trivialization of the disease and to achieve appropriate patient compliance for treatment. In this article a practical diagnostic and treatment algorithm for unguis incarnatus is presented. In mild cases of acute unguis incarnatus a consistent conservative treatment is the first-line strategy showing promising results. In cases of moderate to severe forms of acute unguis incarnatus, surgical procedures that preserve the nail matrix should be applied. For cases of chronic unguis incarnatus without an acute infection, elective partial matrixectomy can be indicated. Prior to any surgical intervention, detailed informed consent must be obtained from the patients. ZUSAMMENFASSUNG Der Unguis incarnatus ist ein häufiges Krankheitsbild, mit dem sich Patienten in der Hausarztpraxis, der dermatologischen Klinik oder der chirurgischen Notaufnahme vorstellen. Häufig führt die inkonsequente konservative Therapie oder die falsch-indizierte operative Intervention zu langwierigen und komplikationsreichen Verläufen, inklusive Rezidiven. Die Patienten sollten über die Komplexität des Nagelorgans aufgeklärt werden, um der Banalisierung der Erkrankung vorzubeugen, und eine entsprechende Compliance in der Therapie zu erreichen. In diesem Manuskript wird die sachgerechte Versorgung des Unguis incarnatus im Sinne eines praktischen Behandlungsalgorithmus dargestellt. Die konsequente konservative Therapie ist bei akutem Unguis incarnatus mit milder Ausprägung die Therapie der ersten Wahl mit guten Behandlungsergebnissen. Nagelerhaltende operative Eingriffe kommen bei moderaten/schweren akuten Formen zum Einsatz. Der chronische Unguis incarnatus, ohne floride Infektion, stellt eine elektive Operationsindikation dar. Sowohl bei den nagelerhaltenden Eingriffen als auch bei erweiterten operativen Maßnahmen ist eine chirurgische Operationsaufklärung obligat
Does the Constitution Provide More Ballot Access Protection for Presidential Elections Than for U.S. House Elections?
Both the U.S. Constitution and The Federalist Papers suggest that voters ought to have more freedom to vote for the candidate of their choice for the U.S. House of Representatives than they do for the President or the U.S. Senate. Yet, strangely, for the last thirty-three years, the U.S. Supreme Court and lower courts have ruled that the Constitution gives voters more freedom to vote for the candidate of their choice in presidential elections than in congressional elections. Also, state legislatures, which have been writing ballot access laws since 1888, have passed laws that make it easier for minor-party and independent candidates to get on the ballot for President than for the U.S. House. As a result, voters in virtually every state invariably have far more choices on their general election ballots for the President than they do for the House. This Article argues that the right of a voter to vote for someone other than a Democrat or a Republican for the House is just as important as a voter’s right to do so for President, and that courts should grant more ballot access protection to minor-party and independent candidates for the House
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Hydrocarbon-free resonance transition 795-nm rubidium laser
An optical resonance transition rubidium laser (5{sup 2}P{sub 1/2} {yields} 5{sup 2}S{sub 1/2}) is demonstrated with a hydrocarbon-free buffer gas. Prior demonstrations of alkali resonance transition lasers have used ethane as either the buffer gas or a buffer gas component to promote rapid fine-structure mixing. However, our experience suggests that the alkali vapor reacts with the ethane producing carbon as one of the reaction products. This degrades long term laser reliability. Our recent experimental results with a 'clean' helium-only buffer gas system pumped by a Ti:sapphire laser demonstrate all the advantages of the original alkali laser system, but without the reliability issues associated with the use of ethane
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