6,511 research outputs found

    Dipoles in thin sheets

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    A flat elastic sheet may contain pointlike conical singularities that carry a metrical "charge" of Gaussian curvature. Adding such elementary defects to a sheet allows one to make many shapes, in a manner broadly analogous to the familiar multipole construction in electrostatics. However, here the underlying field theory is non-linear, and superposition of intrinsic defects is non-trivial as it must respect the immersion of the resulting surface in three dimensions. We consider a "charge-neutral" dipole composed of two conical singularities of opposite sign. Unlike the relatively simple electrostatic case, here there are two distinct stable minima and an infinity of unstable equilibria. We determine the shapes of the minima and evaluate their energies in the thin-sheet regime where bending dominates over stretching. Our predictions are in surprisingly good agreement with experiments on paper sheets.Comment: 20 pages, 5 figures, 2 table

    Effect of homogenisation conditions on recrystallisation in the Al-Mg-Mn alloy AA5454

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    The purpose of the present work is to understand the microstructure development and, particularly, to control the progress of recrystallisation in hot strip in the Al-Mg-Mn alloy AA 5454, which is typically used for the manufacture of structural automotive components. The chemical composition, together with the thermomechanical processing history of this material, has a strong influence on the microstructure of the product and the resulting properties as it is supplied to the customer. Electrical conductivity measurements, thermal analysis and electron microscopy have been carried out to characterise the evolution of precipitation state at various stages in the processing route. The conditions of the homogenisation heat treatment have been varied, and the effect on subsequent recrystallisation after hot rolling has been evaluated in both the as cast and rough rolled condition by optical microscopy techniques. Results indicate that the conditions of homogenisation heat treatment and roughing rolling are critical for the generation of a suitable recrystallised microstructure in AA 5454 hot strip. A new two stage homogenisation practice has been developed to expedite post-rolling recrystallisation in this alloy

    Expressive Body Capture: 3D Hands, Face, and Body from a Single Image

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    To facilitate the analysis of human actions, interactions and emotions, we compute a 3D model of human body pose, hand pose, and facial expression from a single monocular image. To achieve this, we use thousands of 3D scans to train a new, unified, 3D model of the human body, SMPL-X, that extends SMPL with fully articulated hands and an expressive face. Learning to regress the parameters of SMPL-X directly from images is challenging without paired images and 3D ground truth. Consequently, we follow the approach of SMPLify, which estimates 2D features and then optimizes model parameters to fit the features. We improve on SMPLify in several significant ways: (1) we detect 2D features corresponding to the face, hands, and feet and fit the full SMPL-X model to these; (2) we train a new neural network pose prior using a large MoCap dataset; (3) we define a new interpenetration penalty that is both fast and accurate; (4) we automatically detect gender and the appropriate body models (male, female, or neutral); (5) our PyTorch implementation achieves a speedup of more than 8x over Chumpy. We use the new method, SMPLify-X, to fit SMPL-X to both controlled images and images in the wild. We evaluate 3D accuracy on a new curated dataset comprising 100 images with pseudo ground-truth. This is a step towards automatic expressive human capture from monocular RGB data. The models, code, and data are available for research purposes at https://smpl-x.is.tue.mpg.de.Comment: To appear in CVPR 201

    Terminologia anatomica in the past and the future from perspective of 110th anniversary of Polish Anatomical Terminology

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    Professional terminology is commonplace, particularly in the fields of mathematics, medicine, veterinary and natural sciences. The use of the terminology can be international, as it is with Anatomical Terminology (AT). In the early age of modern education, anatomists adopted Latin as the international language for AT. However, at the end of the 20th century, the English language became more predominant around the world. It can be said that the AT is a specific collection of scientific terms. One of the major flaws in early AT was that body structures were described by varying names, while some of the terms was irrational in nature, and confusing. At this time, different international committees were working on preparing a unified final version of the AT, which in the end consisted of 5,640 terms (4,286 originally from the Basle Nomina Anatomica, BNA). Also, each country wanted to have its own nomenclature. In order to accomplish this, each country based their nomenclature on the international AT, and then translated it into their own language. The history of the Polish Anatomical Terminology (PAT) is unique, and follows the events of history. It was first published in 1898, at a time when its neighbours partitioned the territory of Poland. During 150 years, the Polish culture and language was under the Russification and Germanization policy. It is important to note, that even with such difficult circumstances, the PAT was the first national AT in the world. The PAT was a union of the accepted first BNA in Latin and the original Polish anatomical equivalents. This union formed the basis for theoretical and clinical medicine in Poland. (Folia Morphol 2008; 67: 87–97

    Participatory plant breeding: a way to arrive at better-adapted onion varieties

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    The search for varieties that are better adapted to organic farming is a current topic in the organic sector. Breeding programmes specific for organic agriculture should solve this problem. Collaborating with organic farmers in such programmes, particularly in the selection process, can potentially result in varieties better adapted to their needs. Here, we assume that organic farmers' perceptive of plant health is broader than that of conventional breeders. Two organic onion farmers and one conventional onion breeder were monitored in their selection activities in 2004 and 2005 in order to verify whether and in which way this broader view on plant health contributes to improvement of organic varieties. They made selections by positive mass selection in three segregating populations under organic conditions. The monitoring showed that the organic farmers selected in the field for earliness and downy mildew and after storage for bulb characteristics. The conventional breeder selected only after storage. Farmers and breeder applied identical selection directions for bulb traits as a round shape, better hardness and skin firmness. This resulted in smaller bulbs in the breeders’ populations, while the bulbs in the farmer populations were bigger than in the original population. In 2006 and 2007 the new onion populations will be compared with each other and the original populations to determine the selection response

    Satu tinjauan keberkesanan faktor-faktor yang mempengaruhi prestasi pelajar sarjana muda (Lukisan Kejuruteraan) di Kolej Universiti Teknologi Tun Hussein Onn

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    Tujuan kajian ini dilakukan adalah untuk meninjau keberkesanan faktor-faktor yang mempengaruhi prestasi pelajar dalam mataplajaran Lukisan Kejuruteraan di Kolej Universiti Teknologi Tun Hussein Onn (KUiTTHO). Ianya melihat kepada beberapa objektif khusus dalam menentukan prestasi pelajar dalam matapelajaran Lukisan Kejuruteraan, di antara faktor-faktor tersebut adalah dari segi sikap dan minat pelajar serta cara pengajaran pensyarah tersebut dan terhadap kemudahan yang sedia ada di makmal lukisan. Dalam melaksanakan kajian ini terdapat beberapa persoalan kajian yang dilihat iaitu terhadap sikap dan minat pelajar sama ada ianya mempengaruhi prestasi pelajar tersebut dalam matapelajaran lukisan kejuruteraan, juga dari segi cara pengajaran pensyarah dan kemudahan- kemudahan yang sedia ada. Instrumen kajian yang digunakan adalah berbentuk soal selidik dan data yang diperolehi dianalisis bagi tujuan dipersembahkan dalam bentuk carta dan jadual statistical. Kajian ini mendapati kefahaman pelajar terhadap sumber tentang kepentingan lukisan kejuruteraan. Faktor sikap, minat cara pengajaran pensyarah dan kemudahan yang sedia ada di makmal adalah merupakan faktor yang mempengaruhi tahap prestasi pelajar dalam matapelajaran ini. Penekanan yang difokuskan ini adalah supaya pensyarah memberi banyak pendedahan dan kepentingan matapelajaran ini serta mempelbagaikan kaedah pengajaran dan juga mengadakan banyak perbincangan yang berterusan dengan pelajar

    Host plant mediates foraging behavior and mutual interference among adult Stethorus gilvifrons (Coleoptera: Coccinellidae) preying on Tetranychus urticae (Acari: Tetranychidae)

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    Citation: Bayoumy, M. H., Osman, M. A., & Michaud, J. P. (2014). Host plant mediates foraging behavior and mutual interference among adult Stethorus gilvifrons (Coleoptera: Coccinellidae) preying on Tetranychus urticae. Retrieved from http://krex.ksu.eduPhysical plant characteristics can influence predator foraging and their behavioral responses to each other. This study examined the searching efficiency and functional response of adult female Stethorus gilvifrons Mulsant foraging for Tetranychus urticae Koch (Acari: Tetranychidae) on castor bean, common bean, and cucumber leaves. Experiments conducted on leaf discs in arenas for 12 h revealed a type II functional response for S. gilvifrons on all host plants. Per capita searching efficiency and killing power decreased with increasing predator density on all plants, but most notably on common bean, the plant with the highest prey consumption rates, due to greater mutual interference. Attack rates were highest on common bean and lowest on castor bean, whereas handling times were shortest on common bean and longest on cucumber, such that the daily predation rate was maximal on common bean. Host plant interacted with predator and prey densities to affect searching efficiency and functional response, the differences in mite consumption among host plants increasing with predator and prey densities. The waxy layers of castor bean leaves and high trichome counts of cucumber leaves appeared to reduce predator foraging efficiency. Thus, the efficacy of S. gilvifrons against T. urticae is likely to be greatest on plants such as Phaeseolus vulgaris L. that have relatively smooth leaves

    Structures of Two Melanoma-Associated Antigens Suggest Allosteric Regulation of Effector Binding

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    The MAGE (melanoma associated antigen) protein family are tumour-associated proteins normally present only in reproductive tissues such as germ cells of the testis. The human genome encodes over 60 MAGE genes of which one class (containing MAGE-A3 and MAGE-A4) are exclusively expressed in tumours, making them an attractive target for the development of targeted and immunotherapeutic cancer treatments. Some MAGE proteins are thought to play an active role in driving cancer, modulating the activity of E3 ubiquitin ligases on targets related to apoptosis. Here we determined the crystal structures of MAGE- A3 and MAGE-A4. Both proteins crystallized with a terminal peptide bound in a deep cleft between two tandem-arranged winged helix domains. MAGE-A3 (but not MAGE-A4), is pre- dominantly dimeric in solution. Comparison of MAGE-A3 and MAGE-A3 with a structure of an effector-bound MAGE-G1 suggests that a major conformational rearrangement is required for binding, and that this conformational plasticity may be targeted by allosteric binders

    Phylogenetic analyses of peanut resistance gene candidates and screening of different genotypes for polymorphic markers

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    AbstractThe nucleotide-binding-site-leucine-rich-repeat (NBS–LRR)-encoding gene family has attracted much research interest because approximately 75% of the plant disease resistance genes that have been cloned to date are from this gene family. Here, we describe a collection of peanut NBS–LRR resistance gene candidates (RGCs) isolated from peanut (Arachis) species by mining Gene Bank data base. NBS–LRR sequences assembled into TIR-NBS-LRR (75.4%) and non-TIR-NBS-LRR (24.6%) subfamilies. Total of 20 distinct clades were identified and showed a high level of sequence divergence within TIR-NBS and non-TIR-NBS subfamilies. Thirty-four primer pairs were designed from these RGC sequences and used for screening different genotypes belonging to wild and cultivated peanuts. Therefore, peanut RGC identified in this study will provide useful tools for developing DNA markers and cloning the genes for resistance to different pathogens in peanut
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