2,463 research outputs found

    Tangent vectors to a zero set at abnormal points

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    AbstractWe are concerned with sharp characterization of the contingent cone to the set defined by a finite number of equality constraints in the absence of classical regularity (constrained qualification)

    Thyroid Diseases among Patients from Hadhramout Province, Yemen

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    Objective: To determine the histopathological pattern of thyroid diseases among patients in Hadhramout Province, Yemen.Materials and Methods: A descriptive retrospective study was conducted at Ibn Sina Central Teaching Hospital, in Mukalla city, Hadhramout, Yemen between January 2007 and December 2012. Eight hundred and seventeen patients with thyropathy were included in this study diagnosed histologically by experienced pathologists using fine needle aspiration cytology. This was followed up by postoperative pathological thyroid specimen study. The patients in the study were treated medically and surgically by authors.Results: 817 patients with thyropathy were included in the study. There were 716 (87.6%) females and 101(12.4%) males, with a female to male ratio of 7:1. The age of the patients ranged from 5 to 80 years, with a mean age of 37.7±12.2 years. Median age was 35 years. More than half of the patients aged between 21-40 years. The majority of the thyroid lesions were non neoplastic 703 (86%). The most common lesion was simple colloid goiter 578 (82%) followed by thyroid Hashimoto 75 (10.7%). The minority were granulomatous (subacute) thyroiditis, hyperplastic nodule and thyroglossal cyst, 5 (0.7%), 6 (0.9%), 8 (1.1%) respectively. 114 (14%) patients had neoplastic lesions. 61(7.5%) patients had benign adenoma, 2 (1.75%) patients had Hurthel cell adenoma. 43(5.3%) patients had papillary carcinoma while 3 (2.63%) patients had anaplastic carcinoma. The less common malignant neoplastic thyroid lesions were primary lymphoma, follicular and medullary carcinoma, mucoepidermoid carcinoma 2(1.75%), 1(0.9%), 1(0.9%),1 (0.9%) respectively.Conclusion: The most common non-neoplastic thyroid disorder reported in this study is a simple colloid goiter. Adenoma was found to be the most common benign tumor while papillary carcinoma was found to be the most common malignant one. Most cancerous lesions were found within the age groups in the third and the fourth decade, mostly females.Key words: simple colloid goiter, Hashimoto thyroiditis, papillary carcinom

    Human-centred design methods : developing scenarios for robot assisted play informed by user panels and field trials

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    Original article can be found at: http://www.sciencedirect.com/ Copyright ElsevierThis article describes the user-centred development of play scenarios for robot assisted play, as part of the multidisciplinary IROMEC1 project that develops a novel robotic toy for children with special needs. The project investigates how robotic toys can become social mediators, encouraging children with special needs to discover a range of play styles, from solitary to collaborative play (with peers, carers/teachers, parents, etc.). This article explains the developmental process of constructing relevant play scenarios for children with different special needs. Results are presented from consultation with panel of experts (therapists, teachers, parents) who advised on the play needs for the various target user groups and who helped investigate how robotic toys could be used as a play tool to assist in the children’s development. Examples from experimental investigations are provided which have informed the development of scenarios throughout the design process. We conclude by pointing out the potential benefit of this work to a variety of research projects and applications involving human–robot interactions.Peer reviewe

    Efficiency and Detection Accuracy Using Print and Digital Stereo Aerial Photography for Remotely Mapping Vernal Pools in New England Landscapes

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    Aerial imagery has been used to identify potential vernal pools (PVPs) using stereo photographic prints. Stereoplotter photogrammetry now allows digital aerial images to be viewed in stereo (3-Dimensional) to enhance remote sensing capabilities. We used both print and digital imagery to map PVPs in 10 towns in Maine, USA. We used field verification of 771 PVPs to explore efficiency and accuracy of the two methodologies and to determine effects of pool size and land cover on accuracy. We compared known pool locations with National Wetland Inventory (NWI) data. The stereoplotter was more efficient and easier to use than prints. In the towns where print imagery was used, 77.4 % of surveyed PVPs were confirmed as compared to 60.8 % of PVPs surveyed in the towns with digital photography. The higher commission errors using the digital method were likely due to enhanced ability to detect smaller features. Omission errors were common using both print and digital methods. Only 43 % of confirmed vernal pools were located in areas mapped by NWI, suggesting that NWI information does not improve detection accuracy. Aerial photo interpretation continues to be effective for PVP identification in our region and is improved with the use of digital stereoplotters

    Development of a Coherent Doppler Lidar for Precision Maneuvering and Landing of Space Vehicles

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    A coherent Doppler lidar has been developed to address NASAs need for a high-performance, compact, and cost-effective velocity and altitude sensor onboard its landing vehicles. Future robotic and manned missions to planetary bodies require precise ground-relative velocity vector and altitude data to execute complex descent maneuvers and safe, soft landing at a pre-designated site. This lidar sensor, referred to as a Navigation Doppler Lidar, meets the required performance of landing missions while complying with vehicle size, mass, and power constraints. Operating from over five kilometers altitude, the lidar obtains velocity and range precision measurements with 2 cm/sec and 2 meters, respectively, dominated by the vehicle motion. After a series of flight tests onboard helicopters and rocket-powered free-flyer vehicles, the Navigation Doppler Lidar is now being ruggedized for future missions to various destinations in the solar system

    Wood fibers are a crucial microhabitat for cellulose- and xylan- degrading bacteria in the hindgut of the wood-feeding beetle Odontotaenius disjunctus

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    IntroductionWood digestion in insects relies on the maintenance of a mosaic of numerous microhabitats, each colonized by distinct microbiomes. Understanding the division of digestive labor between these microhabitats- is central to understanding the physiology and evolution of symbiotic wood digestion. A microhabitat that has emerged to be of direct relevance to the process of lignocellulose digestion is the surface of ingested plant material. Wood particles in the guts of some termites are colonized by a specialized bacterial fiber-digesting microbiome, but whether this represents a widespread strategy among insect lineages that have independently evolved wood-feeding remains an open question.MethodsIn this study, we investigated the bacterial communities specifically associated with wood fibers in the gut of the passalid beetle Odontotaenius disjunctus. We developed a Percoll-based centrifugation method to isolate and enrich the wood particles from the anterior hindgut, allowing us to access the wood fibers and their associated microbiome. We then performed assays of enzyme activity and used short-read and long-read amplicon sequencing of the 16S rRNA gene to identify the composition of the fiber-associated microbiome.ResultsOur assays demonstrated that the anterior hindgut, which houses a majority of the bacterial load, is an important site for lignocellulose digestion. Wood particles enriched from the anterior hindgut contribute to a large proportion of the total enzyme activity. The sequencing revealed that O. disjunctus, like termites, harbors a distinct fiber-associated microbiome, but notably, its community is enriched in insect-specific groups of Lactococcus and Turicibacter.DiscussionOur study underscores the importance of microhabitats in fostering the complex symbiotic relationships between wood-feeding insects and their microbiomes. The discovery of distinct fiber-digesting symbionts in O. disjunctus, compared to termites, highlights the diverse evolutionary paths insects have taken to adapt to a challenging diet
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