Soft tissue artifact distribution on lower limbs during treadmill gait: Influence of skin markers' location on cluster design.

Segment poses and joint kinematics estimated from skin markers are highly affected by soft tissue artifact (STA) and its rigid motion component (STARM). While four marker-clusters could decrease the STA non-rigid motion during gait activity, other data, such as marker location or STARM patterns, would be crucial to compensate for STA in clinical gait analysis. The present study proposed 1) to devise a comprehensive average map illustrating the spatial distribution of STA for the lower limb during treadmill gait and 2) to analyze STARM from four marker-clusters assigned to areas extracted from spatial distribution. All experiments were realized using a stereophotogrammetric system to track the skin markers and a bi-plane fluoroscopic system to track the knee prosthesis. Computation of the spatial distribution of STA was realized on 19 subjects using 80 markers apposed on the lower limb. Three different areas were extracted from the distribution map of the thigh. The marker displacement reached a maximum of 24.9mm and 15.3mm in the proximal areas of thigh and shank, respectively. STARM was larger on thigh than the shank with RMS error in cluster orientations between 1.2° and 8.1°. The translation RMS errors were also large (3.0mm to 16.2mm). No marker-cluster correctly compensated for STARM. However, the coefficient of multiple correlations exhibited excellent scores between skin and bone kinematics, as well as for STARM between subjects. These correlations highlight dependencies between STARM and the kinematic components. This study provides new insights for modeling STARM for gait activity.

Les neurosciences au Tribunal : de la responsabilité à la dangerosité, enjeux éthiques soulevés par la nouvelle loi française

AIM: In the past few years, spectacular progress in neuroscience has led to the emergence of a new interdisciplinary field, the so-called "neurolaw" whose goal is to explore the effects of neuroscientific discoveries on legal proceedings and legal rules and standards. In the United States, a number of neuroscientific researches are designed specifically to explore legally relevant topics and a case-law has already been developed. In Europe, neuroscientific evidence is increasingly being used in criminal courtrooms, as part of psychiatric testimony, nourishing the debate about the legal implications of brain research in psychiatric-legal settings. Though largely debated, up to now the use of neuroscience in legal contexts had not specifically been regulated by any legislation. In 2011, with the new bioethics law, France has become the first country to admit by law the use of brain imaging in judicial expertise. According to the new law, brain imaging techniques can be used only for medical purposes, or scientific research, or in the context of judicial expertise. This study aims to give an overview of the current state of the neurolaw in the US and Europe, and to investigate the ethical issues raised by this new law and its potential impact on the rights and civil liberties of the offenders. METHOD: An overview of the emergence and development of "neurolaw" in the United States and Europe is given. Then, the new French law is examined in the light of the relevant debates in the French parliament. Consequently, we outline the current tendencies in Neurolaw literature to focus on assessments of responsibility, rather than dangerousness. This tendency is analysed notably in relation to the legal context relevant to criminal policies in France, where recent changes in the legislation and practice of forensic psychiatry show that dangerousness assessments have become paramount in the process of judicial decision. Finally, the potential interpretations of neuroscientific data introduced into psychiatric testimonies by judges are explored. RESULTS: The examination of parliamentary debates showed that the new French law allowing neuroimaging techniques in judicial expertise was introduced in the aim to provide a legal framework that would protect the subject against potential misuses of neuroscience. The underlying fear above all, was that this technology be used as a lie detector, or as a means to predict the subject's behaviour. However, the possibility of such misuse remains open. Contrary to the legislator's wish, the defendant is not fully guaranteed against uses of neuroimaging techniques in criminal courts that would go against their interests and rights. In fact, the examination of the recently adopted legislation in France shows that assessments of dangerousness and of risk of recidivism have become central elements of the criminal policy, which makes it possible, if not likely that neuroimaging techniques be used for the evaluation of the dangerousness of the defendant. This could entail risks for the latter, as judges could perceive neuroscientific data as hard evidence, more scientific and reliable than the soft data of traditional psychiatry. If such neuroscientific data are interpreted as signs of potential dangerousness of a subject rather than as signs of criminal responsibility, defendants may become subjected to longer penalties or measures aiming to ensure public safety in the detriment of their freedom. CONCLUSION: In the current context of accentuated societal need for security, the judge and the expert-psychiatrist are increasingly asked to evaluate the dangerousness of a subject, regardless of their responsibility. Influenced by this policy model, the judge might tend to use neuroscientific data introduced by an expert as signs of dangerousness. Such uses, especially when they subjugate an individual's interest to those of society, might entail serious threats to an individual's freedom and civil liberties.

Molecular dynamics simulation of the spherical electrical double layer of a soft nanoparticle. Effect of the surface and counterion valence

Molecular dynamics simulations were performed to study the ion and water distribution around a spherical charged nanoparticle. A soft nanoparticle model was designed using a set of hydrophobic interaction sites distributed in six concentric spherical layers. In order to simulate the effect of charged functionalyzed groups on the nanoparticle surface, a set of charged sites were distributed in the outer layer. Four charged nanoparticle models, from a surface charge value of −0.035 Cm−2 to − 0.28 Cm−2, were studied in NaCl and CaCl2 salt solutions at 1 M and 0.1 M concentrations to evaluate the effect of the surface charge, counterion valence, and concentration of added salt. We obtain that Na + and Ca2 + ions enter inside the soft nanoparticle. Monovalent ions are more accumulated inside the nanoparticle surface, whereas divalent ions are more accumulated just in the plane of the nanoparticle surface sites. The increasing of the the salt concentration has little effect on the internalization of counterions, but significantly reduces the number of water molecules that enter inside the nanoparticle. The manner of distributing the surface charge in the nanoparticle (uniformly over all surface sites or discretely over a limited set of randomly selected sites) considerably affects the distribution of counterions in the proximities of the nanoparticle surface.

Sarcoma de Ewing: aspectos clínicos e radiográficos de 226 casos

OBJETIVO: Avaliar os aspectos radiográficos e clínicos presentes em pacientes com o diagnóstico de sarcoma de Ewing confirmado por histopatologia. MATERIAIS E MÉTODOS: Foram analisados, neste trabalho, os dados clínicos e radiográficos (quando disponíveis) de 226 pacientes com o diagnóstico de sarcoma de Ewing ósseo. RESULTADOS: Dos casos avaliados, 61,5% (139) eram do sexo masculino e 83,7% (189) eram brancos. A mediana de idade dos pacientes foi de 14 anos e a topografia mais freqüente das lesões foi o osso ilíaco, em 13,7% (31) dos casos. O aspecto radiográfico mais comum foi o de lesão lítica com reação periosteal (padrões variados), em 32,7% (74) dos casos. CONCLUSÃO: O sarcoma de Ewing ósseo é uma neoplasia bastante agressiva, ocorrendo mais comumente em indivíduos na segunda década de vida e cujo aspecto radiográfico mais comum é o de lesão lítica com reação periosteal típica de lesão agressiva.

Sarcoma fibromixóide de baixo grau da parede torácica: relato de caso

Este relato descreve um caso de sarcoma fibromixóide de baixo grau na parede torácica em uma paciente feminina de 23 anos de idade. A radiografia de tórax e a tomografia computadorizada demonstraram massa heterogênea na região inferior do hemitórax direito, com necrose e focos de calcificação. O exame histológico foi sugestivo de leiomioma, mas a imuno-histoquímica definiu o diagnóstico de sarcoma fibromixóide de baixo grau. A evolução clínica do caso foi boa, apesar dos aspectos de malignidade demonstrados na tomografia computadorizada.

A qualitative study of adolescents with medically unexplained symptoms and their parents. Part 2: How is healthcare perceived?

Medically unexplained symptoms (MUS) are common among adolescents and an important cause of clinical visits. This study sought to understand the experiences with, and perceptions of, the healthcare of adolescents who have MUS and their parents. Using a qualitative approach, six focus groups and two individual interviews were conducted with a total of ten adolescents and sixteen parents. The participants were recruited in a university hospital in Switzerland. A thematic analysis was conducted in accordance with the Grounded Theory. Six main themes emerged: needing a label for the symptoms, seeking an etiology to explain the symptoms, negotiating the medical system, medication and treatments, interactions with doctors, and the inclusion of parents during consultations. Transcending these themes, however, was the need for good communication between the adolescents, their parents and the clinicians. When explaining the symptoms, clinicians should make sure to discuss the results, investigations and lack of organic origin.

A qualitative study of adolescents with medically unexplained symptoms and their parents. Part 1: Experiences and impact on daily life.

Medically unexplained symptoms (MUS) are common among adolescents and are frequently encountered in primary care. Our aim was to explore how these adolescents and their parents experience the condition and its impact on their daily lives and to provide recommendations for health professionals. Using a qualitative approach, six focus groups and two individual interviews were conducted. These involved a total of ten adolescents with different types of MUS and sixteen parents. The respondents were recruited in a university hospital in Switzerland. A thematic analysis was conducted according to the Grounded Theory. The analysis of the data highlighted four core themes: disbelief, being different, concealing symptoms, and priority to adolescent's health. Transcending these themes was a core issue regarding the discrepancy between the strategies that adolescents and their parents use to cope with the symptoms. Health professionals should be made aware of the emotional needs of these patients and their families.

Pienen ohjelmistoyrityksen kansainvälistyminen kumppanien avulla: kumppanien etsintä ja arviointi

Tämän tutkimuksen tavoitteena oli tutkia pienen ohjelmistoyrityksen kansainvälistymistä kumppanien avulla. Tutkimuksessa selvitettiin ohjelmistoyritysten kansainvälistymistä, kumppanien roolia osana kansainvälistymistä, sekä kuinka tarvittavia kumppaneita tulisi etsiä ja arvioida. Tutkielma jakaantuu teoreettiseen ja empiiriseen osaan. Teoreettinen osa keskittyy tarkastelemaan pienen ohjelmistoyrityksen kansainvälistymistä kumppanien avulla sekä kumppanien etsintää ja arviointia. Informaatiota kerättiin kirjallisuuteen ja aikaisempiin tutkimuksiin perehtymällä, sekä teemahaastattelujen avulla. Tutkimuksessa käytettiin apuna laadullisia tutkimusmenetelmiä. Haastatteluista saatu materiaali analysoitiin teoriassa nousseiden teemojen avulla. Tutkimustulokset osoittavat, että pienen ohjelmistoyrityksen kansainvälistyminen on vahvasti riippuvainen resursseja tarjoavasta kumppanista. Pienen yrityksen resurssit eivät riitä kansainvälistymään yksin ja resurssit rajoittavat myös kumppanin etsintää ja arviointia.

Sarcoma de Kaposi relacionado à síndrome da imunodeficiência adquirida: características do comprometimento hepático na tomografia computadorizada e na ressonância magnética

Sarcoma de Kaposi é uma neoplasia associada a condições de imunossupressão que acomete os vasos linfáticos e sanguíneos. É a neoplasia intra-hepática mais comum na síndrome da imunodeficiência adquirida. A tomografia computadorizada e a ressonância magnética revelam múltiplos pequenos nódulos, proeminência e realce dos planos periportais, devido à presença de tecido neoplásico. Os autores descrevem um caso de paciente masculino, de 47 anos de idade, com síndrome da imunodeficiência adquirida e sarcoma de Kaposi disseminado.

Dual-Energy CT: Basic Principles, Technical Approaches, and Applications in Musculoskeletal Imaging (Part 1).

In recent years, technological advances have allowed manufacturers to implement dual-energy computed tomography (DECT) on clinical scanners. With its unique ability to differentiate basis materials by their atomic number, DECT has opened new perspectives in imaging. DECT has been used successfully in musculoskeletal imaging with applications ranging from detection, characterization, and quantification of crystal and iron deposits; to simulation of noncalcium (improving the visualization of bone marrow lesions) or noniodine images. Furthermore, the data acquired with DECT can be postprocessed to generate monoenergetic images of varying kiloelectron volts, providing new methods for image contrast optimization as well as metal artifact reduction. The first part of this article reviews the basic principles and technical aspects of DECT including radiation dose considerations. The second part focuses on applications of DECT to musculoskeletal imaging including gout and other crystal-induced arthropathies, virtual noncalcium images for the study of bone marrow lesions, the study of collagenous structures, applications in computed tomography arthrography, as well as the detection of hemosiderin and metal particles.

Optimization of Radiation Dose and Image Quality in Musculoskeletal CT: Emphasis on Iterative Reconstruction Techniques (Part 1).

Computed tomography (CT) is a modality of choice for the study of the musculoskeletal system for various indications including the study of bone, calcifications, internal derangements of joints (with CT arthrography), as well as periprosthetic complications. However, CT remains intrinsically limited by the fact that it exposes patients to ionizing radiation. Scanning protocols need to be optimized to achieve diagnostic image quality at the lowest radiation dose possible. In this optimization process, the radiologist needs to be familiar with the parameters used to quantify radiation dose and image quality. CT imaging of the musculoskeletal system has certain specificities including the focus on high-contrast objects (i.e., in CT of bone or CT arthrography). These characteristics need to be taken into account when defining a strategy to optimize dose and when choosing the best combination of scanning parameters. In the first part of this review, we present the parameters used for the evaluation and quantification of radiation dose and image quality. In the second part, we discuss different strategies to optimize radiation dose and image quality at CT, with a focus on the musculoskeletal system and the use of novel iterative reconstruction techniques.