589 research outputs found
Bone and soft tissue tumors of hip and pelvis
AbstractObjective is to identify epidemiologic and radiologic criteria allowing specific diagnoses of tumors and tumor-like lesions in the hip region and pelvis, and to optimize pre-operative staging.Patients with pelvic tumors are usually older, and their tumors are larger relative to patients with tumors in extremities. The majority of tumors in the pelvis are malignant (metastases, myeloma, chondrosarcoma, Ewing-, osteo-, and MFH/fibrosarcoma), while those in the proximal femur are in majority benign (fibrous dysplasia, solitary bone cyst, and osteoid osteoma). Soft tissue masses in the thigh in the elderly are typically sarcomas without tumor specific signs.Common tumor-like lesions occurring in the hip and pelvis that can mimic neoplasm are: infections (including tuberculosis), insufficiency/avulsion fractures, cysts, fibrous dysplasia, aneurysmal bone cyst, Langerhans cell histiocytosis, and Paget's disease.Local MR staging is based on the compartmental anatomy. The psoas and gluteal muscles are easily invaded by sarcoma originating in the ileum. The pectineus muscle protects the neurovascular bundle at the level of the hip. The thigh is separated into three compartments, some structures (Sartorius muscle) cross borders between compartments. Immobile joints (SI-joints, osteoarthritic hip) are relatively easily crossed by sarcoma and giant cell tumor
Understanding communicative actions:A repetitive TMS study
Previous work has shown that the right posterior superior temporal sulcus (RpSTS) is involved in inferring both instrumental goals and communicative intentions of observed actions (1, 2), using previous knowledge to generate perceptual and/or conceptual inferences (3, 4). Here, we disturb neural activity in RpSTS to test whether this region is necessary for understanding the meaning of novel communicative actions. Thirteen subjects received two 20 min sessions of low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS), either over RpSTS (50,-42,14) or over a control region (area MT+, -43,-70,10), before performance of a communicative game and a control task. The game involved controlled non-verbal communicative interactions between pairs of subjects (40 trials). Each pair was asked to jointly create a goal configuration of two geometrical tokens, using the movements of the tokens on a gameboard as the only available communicative channel (5). One participant (a confederate) knew the goal configuration, and she moved her token on the gameboard to inform an addressee (a participant) where and how to position his token. The control task was a visual search paradigm that involved the same stimuli, responses, joint attention, and inter-subjects dependencies, but no communicative necessities. Performance was indexed by Task Efficiency, defined as the number of correct responses per unit of planning time, and by Efficiency Rate, defined as the rate of change (across trials) in Task Efficiency. After rTMS over RpSTS, but not left MT+, the Efficiency Rate of the addresses was reduced in the communicative game, but not in the visual search. In contrast, after rTMS over left MT+, subjects were not able to benefit from experience gained during the previous trials of the visual search task (Task X Site interaction, p<0.05). There were no corresponding interactions between tasks and site of rTMS intervention on the Task Efficiency parameter. These findings qualify how RpSTS contributes to understanding the meaning of non-verbal communicative actions. Repetitive TMS over RpSTS did not disrupt the ability of addressees to interpret novel communicative actions. Rather, this region appears to be necessary for incorporating previous knowledge, accumulated during interactions with a communicative partner, to constrain the inferential process that leads to action understanding
The discursive construction of childhood and youth in AIDS interventions in Lesotho's education sector: Beyond global-local dichotomies
This is the post-print version of this article. The definitive, peer-reviewed and edited version of this article is published in Environment and Planning D,Society and Space 28(5) 791 â 810, 2010, available from the link below. Copyright @ 2010 Pion.In southern Africa interventions to halt the spread of AIDS and address its social impacts are commonly targeted at young people, in many cases through the education sector. In Lesotho, education-sector responses to AIDS are the product of negotiation between a range of âlocalâ and âglobalâ actors. Although many interventions are put forward as government policy and implemented by teachers in schools, funding is often provided by bilateral and multilateral donors, and the international âAIDS industryââin the form of UN agencies and international NGOsâsets agendas and makes prescriptions. This paper analyses interviews conducted with policy makers and practitioners in Lesotho and a variety of documents, critically examining the discourses of childhood and youth that are mobilised in producing changes in education policy and practice to address AIDS. Focusing on bursary schemes, life-skills education, and rights-based approaches, the paper concludes that, although dominant âglobalâ discourses are readily identified, they are not simply imported wholesale from the West, but rather are transformed through the organisations and personnel involved in designing and implementing interventions. Nonetheless, the connections through which these discourses are made, and children are subjectified, are central to the power dynamics of neoliberal globalisation. Although the representations of childhood and youth produced through the interventions are hybrid products of local and global discourses, the power relations underlying them are such that they, often unintentionally, serve a neoliberal agenda by depicting young people as individuals in need of saving, of developing personal autonomy, or of exercising individual rights.RGS-IB
Poor Trail Making Test Performance Is Directly Associated with Altered Dual Task Prioritization in the Elderly â Baseline Results from the TREND Study
BACKGROUND: Deterioration of executive functions in the elderly has been associated with impairments in walking performance. This may be caused by limited cognitive flexibility and working memory, but could also be caused by altered prioritization of simultaneously performed tasks. To disentangle these options we investigated the associations between Trail Making Test performance--which specifically measures cognitive flexibility and working memory--and dual task costs, a measure of prioritization. METHODOLOGY AND PRINCIPAL FINDINGS: Out of the TREND study (Tuebinger evaluation of Risk factors for Early detection of Neurodegenerative Disorders), 686 neurodegeneratively healthy, non-demented elderly aged 50 to 80 years were classified according to their Trail Making Test performance (delta TMT; TMT-B minus TMT-A). The subjects performed 20 m walks with habitual and maximum speed. Dual tasking performance was tested with walking at maximum speed, in combination with checking boxes on a clipboard, and subtracting serial 7 s at maximum speeds. As expected, the poor TMT group performed worse when subtracting serial 7 s under single and dual task conditions, and they walked more slowly when simultaneously subtracting serial 7 s, compared to the good TMT performers. In the walking when subtracting serial 7 s condition but not in the other 3 conditions, dual task costs were higher in the poor TMT performers (median 20%; range -6 to 58%) compared to the good performers (17%; -16 to 43%; p<0.001). To the contrary, the proportion of the poor TMT performance group that made calculation errors under the dual tasking situation was lower than under the single task situation, but higher in the good TMT performance group (poor performers, -1.6%; good performers, +3%; pâ=â0.035). CONCLUSION: Under most challenging conditions, the elderly with poor TMT performance prioritize the cognitive task at the expense of walking velocity. This indicates that poor cognitive flexibility and working memory are directly associated with altered prioritization
Promptness and Bounded Fairness in Concurrent and Parameterized Systems
We investigate the satisfaction of specifications in Prompt
Linear Temporal Logic (Prompt-LTL) by concurrent systems. Prompt-LTL is an extension of LTL that allows to specify parametric bounds onthe satisfaction of eventualities, thus adding a quantitative aspect to the specification language. We establish a connection between bounded fairness, bounded stutter equivalence, and the satisfaction of Prompt-LTL\X
formulas. Based on this connection, we prove the first cutoff results for different classes of systems with a parametric number of components and quantitative specifications, thereby identifying previously unknown
decidable fragments of the parameterized model checking problem
Microstructural and strength study of MIG welded joints of AW7020 aluminium alloy, as a function of joint geometry
[EN] Medium strength AW7XXX aluminium alloys are widely used as welded structures and in transportation. The applications of these alloys are limited by the behaviour of the welded joints. There is no agreement on the joint geometry that must be used on 5 mm welds. The microhardness evolution is one of the most important strength indicators. For this reason, the aim of this work is to study the influence of welded joint geometry on microhardness profile and on the microstructure of a MIG welded AW7020 aluminium alloy, using AW5256 filler.Bloem, C.; Salvador Moya, MD.; AmigĂł, V.; Vicente-Escuder, Ă. (2000). Microstructural and strength study of MIG welded joints of AW7020 aluminium alloy, as a function of joint geometry. Welding International. 14(12):970-974. doi:10.1080/09507110009549300S970974141
Parameterized Verification of Systems with Global Synchronization and Guards
Inspired by distributed applications that use consensus or other agreement
protocols for global coordination, we define a new computational model for
parameterized systems that is based on a general global synchronization
primitive and allows for global transition guards. Our model generalizes many
existing models in the literature, including broadcast protocols and guarded
protocols. We show that reachability properties are decidable for systems
without guards, and give sufficient conditions under which they remain
decidable in the presence of guards. Furthermore, we investigate cutoffs for
reachability properties and provide sufficient conditions for small cutoffs in
a number of cases that are inspired by our target applications.Comment: Accepted at CAV 202
101 Dothideomycetes genomes: A test case for predicting lifestyles and emergence of pathogens.
Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species
HPV vaccination introduction worldwide and WHO and UNICEF estimates of national HPV immunization coverage 2010â2019
WHO/UNICEF estimates for HPV vaccination coverage from 2010 to 2019 are analyzed against the backdrop of the 90% coverage target for HPV vaccination by 2030 set in the recently approved global strategy for cervical cancer elimination as a public health problem. As of June 2020, 107 (55%) of the 194 WHO Member States have introduced HPV vaccination. The Americas and Europe are by far the WHO regions with the most introductions, 85% and 77% of their countries having already introduced respectively. A record number of introductions was observed in 2019, most of which in low- and middle- income countries (LMIC) where access has been limited. Programs had an average performance coverage of around 67% for the first dose and 53% for the final dose of HPV. LMICs performed on average better than high- income countries for the first dose, but worse for the last dose due to higher dropout. Only 5 (6%) countries achieved coverages with the final dose of more than 90%, 22 countries (21%) achieved coverages of 75% or higher while 35 (40%) had a final dose coverage of 50% or less. When expressed as world population coverage (i.e., weighted by population size), global coverage of the final HPV dose for 2019 is estimated at 15%. There is a long way to go to meet the 2030 elimination target of 90%. In the post-COVID era attention should be paid to maintain the pace of introductions, specially ensuring the most populous countries introduce, and further improving program performance globally
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