328 research outputs found
Cam-type FAI: is the alpha angle the best MR arthrography has to offer? (Skeletal Radiol. 2009;38(9):855â62)
Comparative reliability and diagnostic performance of conventional 3T magnetic resonance imaging and 1.5T magnetic resonance arthrography for the evaluation of internal derangement of the hip
Objective; To compare the diagnostic accuracy of conventional 3T MRI against 1.5T MR arthrography (MRA) in patients with clinical femoroacetabular impingement (FAI).
Methods; Sixty-eight consecutive patients with clinical FAI underwent both 1.5T MRA and 3T MRI. Imaging was prospectively analysed by two musculoskeletal radiologists, blinded to patient outcomes and scored for internal derangement including labral and cartilage abnormality. Interobserver variation was assessed by kappa analysis. Thirty-nine patients subsequently underwent hip arthroscopy and surgical results and radiology findings were analysed.
Results; Both readers had higher sensitivities for detecting labral tears with 3T MRI compared to 1.5T MRA (not statistically significant p=0.07). For acetabular cartilage defect both readers had higher statistically significant sensitivities using 3T MRI compared to 1.5T MRA (p=0.02). Both readers had a slightly higher sensitivity for detecting delamination with 1.5T MRA compared to 3T MRI, but these differences were not statistically significant (p=0.66). Interobserver agreement was substantial to perfect agreement for all parameters except the identification of delamination (3T MRI showed moderate agreement and 1.5T MRA substantial agreement).
Conclusion; Conventional 3T MRI may be at least equivalent to 1.5T MRA in detecting acetabular labrum and possibly superior to 1.5T MRA in detecting cartilage defects in patients with suspected FAI
Prevalence and characteristics of cam-type femoroacetabular deformity in 100 hips with symptomatic acetabular dysplasia: a case control study
National culture and tourist destination choice in the UK and Venezuela: an exploratory and preliminary study
National culture determines consumer attitudes and behaviour. While this holds true for tourism
consumption, little research has sought to better understand the effect of culture on tourist
destination choice. The geographical scope of analysis has also been restricted. This study
employs the Hofstedeâs cultural dimensions framework to conduct an exploratory, qualitative
evaluation of the influence of the tourist cultural background on destination choice. It focuses on
the UK and Venezuela, the two countries with significant cultural differences and forecast
growth in outbound tourism. The study shows the distinct role of culture in tourist preferences
for destination choice and structure of travel groups. The effect of culture is also recorded in how
tourists research destinations prior to visit and perceive travel risks, thus ultimately influencing
their motivation to travel. Recommendations are developed on how to integrate knowledge on
the cultural background of tourists into tourism management and policy-making practices
The present state of research into industrial clusters and districts. Content analysis of material published 1997-2006
[EN] The aim of this work is to help gain a better understanding of the research conducted on territorial agglomerations of firms at a multidisciplinary level. To this end, an analysis was performed of the contents of the most significant scientific literature on economics, management, planning and development, urban studies and geography published over the period 1997-2006. From the results, a database of 142 papers from 43 journals was then elaborated. An analysis of these works reveals the level of development of the main lines of research in this field and, consequently, makes it possible to detect the topics that require greater attention and that can be the object of future research for researchers and academics. The main conclusions include the growing number of studies conducted on the subject in recent years, as well as a greater predominance of empirical research over conceptual work, and the existence of a significant change in the topics or lines of research throughout the period under study. © 2012 Copyright Taylor and Francis Group, LLC.This research was financed by the Spanish Ministry of Education and Science, National R&D & Innovation Plan 2007â2010, under the project entitled âEl Distrito Industrial: el impacto del Capital Social sobre la GestioÂŽn de la Cadena de Suministroâ (The Industrial District: the impact of Social Capital on the management of the Supply Chain) (SEJ2007- 62876/ECON).Martinez-Fernandez, M.; CapĂł Vicedo, J.; Vallet-Bellmunt, T. (2012). The present state of research into industrial clusters and districts. Content analysis of material published 1997-2006. European Planning Studies. 20(2):281-304. doi:10.1080/09654313.2012.650906S28130420
The effectiveness of green advertisements : combining ad-based and consumer-based research
Quantitative Assessment of Whole-Body Tumor Burden in Adult Patients with Neurofibromatosis
Purpose
Patients with neurofibromatosis 1 (NF1), NF2, and schwannomatosis are at risk for multiple nerve sheath tumors and premature mortality. Traditional magnetic resonance imaging (MRI) has limited ability to assess disease burden accurately. The aim of this study was to establish an international cohort of patients with quantified whole-body internal tumor burden and to correlate tumor burden with clinical features of disease.
Methods
We determined the number, volume, and distribution of internal nerve sheath tumors in patients using whole-body MRI (WBMRI) and three-dimensional computerized volumetry. We quantified the distribution of tumor volume across body regions and used unsupervised cluster analysis to group patients based on tumor distribution. We correlated the presence and volume of internal tumors with disease-related and demographic factors.
Results
WBMRI identified 1286 tumors in 145/247 patients (59%). Schwannomatosis patients had the highest prevalence of tumors (Pâ=â0.03), but NF1 patients had the highest median tumor volume (Pâ=â0.02). Tumor volume was unevenly distributed across body regions with overrepresentation of the head/neck and pelvis. Risk factors for internal nerve sheath tumors included decreasing numbers of cafĂ©-au-lait macules in NF1 patients (Pâ=â0.003) and history of skeletal abnormalities in NF2 patients (Pâ=â0.09). Risk factors for higher tumor volume included female gender (Pâ=â0.05) and increasing subcutaneous neurofibromas (Pâ=â0.03) in NF1 patients, absence of cutaneous schwannomas in NF2 patients (Pâ=â0.06), and increasing age in schwannomatosis patients (pâ=â0.10).
Conclusion
WBMRI provides a comprehensive phenotype of neurofibromatosis patients, identifies distinct anatomic subgroups, and provides the basis for investigating molecular biomarkers that correlate with unique disease manifestations
Femoroacetabular impingement: normal values of the quantitative morphometric parameters in asymptomatic hips.
OBJECTIVE: To determine the means and the reference intervals of the quantitative morphometric parameters of femoroacetabular impingement (FAI) in normal hips with high-resolution computed tomography (CT).
METHODS: We prospectively included 94 adult individuals who underwent CT for thoracic, abdominal or urologic pathologies. Patients with a clinical history of hip pathology and/or with osteoarthritis on CT were excluded. We calculated means and 95 % reference intervals for imaging signs of cam-type (alpha angle at 90° and 45° and femoral head-neck offset) and pincer-type impingement (acetabular version angle, lateral centre-edge angle and acetabular index).
RESULTS: The 95 % reference interval limits were all far beyond the abnormal thresholds found in the literature for cam-type and to a lesser extent for pincer-type FAI. The upper limits of the reference intervals for the alpha angles (at 90°/45°) were 68°/83° (men) and 69°/84° (women), compared to thresholds from the literature (50°, 55° or 60°). Reference intervals were similar between genders for cam-type parameters, and slightly differed for pincer-type.
CONCLUSION: The 95Â % reference intervals of morphometric measurements of FAI in asymptomatic hips were beyond the abnormal thresholds, which was especially true for cam-type FAI. Our results suggest the need for redefining the current morphometric parameters used in the diagnosis of FAI.
KEY POINTS: ? 95Â % reference intervals limits of FAI morphotype were beyond currently defined thresholds. ? Reference intervals of pincer-type morphotype measurements were close to current definitions. ? Reference intervals of cam-type morphotype measurements were far beyond the current definitions. ? Current morphometric definitions of cam-type morphotype should be used with care
Green consumer segmentation: managerial and environmental implications from the perspective of business strategies and practices
With the new millennium, environmental concern entered a new phase,
with stricter governmental regulations and incentives. Currently, within environmental
issues, there is a broader challenge to commitment with economic and social
goals. This is motivating companies and organizations to participate in transformation
processes with the aim of minimizing the negative impacts of their activities.
Within this context, new business philosophies, emerged empowering organizations
to consider sustainability issues that have come to be viewed as an innovative and
differentiating factor, providing competitive advantages (Fraj-Andres, MartinezSalinas,
& Matute-Vallejo. Journal of Business Ethics, 88,263-286, 2009; Leipziger.
The corporate responsibility code book. Greenleaf Publishing Limited, 2016;
Leipziger. The corporate responsibility code book. Greenleaf Publishing Limited,
2016). Therefore, organizations have begun incorporating these concerns in their
processes, adopting green management policies, and including green marketing
strategies in order to remain competitive (Straughan & Roberts. Journal of Consumer
Marketing, 16(6), 558-575, 1999; Rivera-Camino. European Journal of Marketing,
41, 1328-1358, 2007). From the marketing perspective, the importance of understanding
green consumer behaviour in order to develop better segmentation and
targeting strategies is highlighted. Green consumers are changing significantly.
Consumers, although with some reluctance, are moving to greener products. The
Mintel organization reported that the number of consumers buying green has tripled in recent years. Furthermore, it found that the number of consumers that never
bought green products have decreased. These results show that widespread environmental
awareness had an important role in purchasing behaviour, with more consumers
considering the environmental impact of their buying decisions and looking
for a greener alternative to their conventional purchasing options. The existing literature suggests that previous research regarding the green consumer profile has
different perspectives. The first group of researchers attempted to characterize green
consumer profile using sociodemographic variables such as age, gender, education,
income and occupation. In tum, the second group of researchers used psychographic
variables instead of sociodemographic ones (Mainieri, Barnett, Valdero, Unipan, &
Oskamp. Journal of Social Psychology, 137(2), 189-204, 1997). This chapter aims
to better explore the importance of green consumer segmentation and its implications
from a management point of view. More specifically, the aim is to analyze
which variables better characterize green consumers (sociodemographic and psychographic).
At the end, a theoretical framework is proposed to enable and support
organizations to better understand green consumer profile. It also enables managers
and marketers to target and develop better marketing strategies for these segments.info:eu-repo/semantics/publishedVersio
Magnetic resonance arthrography of the hip: technique and spectrum of findings in younger patients
Magnetic resonance(MR) imaging is the reference imaging technique in the evaluation of hip abnormalities. However, in some pathological conditionsâsuch as lesions of the labrum, cartilaginous lesions, femoroacetabular impingement, intra-articular foreign bodies, or in the pre-operative work-up of developmental dysplasia of the hipâintra-articular injection of a contrast medium is required to obtain a precise diagnosis. This article reviews the technical aspects, contraindications, normal appearance and potential pitfalls of MR arthrography, and illustrates the radiological appearance of commonly encountered conditions
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