157 research outputs found
Advances in Natural Language Question Answering: A Review
Question Answering has recently received high attention from artificial
intelligence communities due to the advancements in learning technologies.
Early question answering models used rule-based approaches and moved to the
statistical approach to address the vastly available information. However,
statistical approaches are shown to underperform in handling the dynamic nature
and the variation of language. Therefore, learning models have shown the
capability of handling the dynamic nature and variations in language. Many deep
learning methods have been introduced to question answering. Most of the deep
learning approaches have shown to achieve higher results compared to machine
learning and statistical methods. The dynamic nature of language has profited
from the nonlinear learning in deep learning. This has created prominent
success and a spike in work on question answering. This paper discusses the
successes and challenges in question answering question answering systems and
techniques that are used in these challenges
Graphene-based Wireless Agile Interconnects for Massive Heterogeneous Multi-chip Processors
The main design principles in computer architecture have recently shifted from a monolithic scaling-driven approach to the development of heterogeneous architectures that tightly co-integrate multiple specialized processor and memory chiplets. In such data-hungry multi-chip architectures, current Networksin- Package (NiPs) may not be enough to cater to their heterogeneous and fast-changing communication demands. This position paper makes the case for wireless in-package networking as the enabler of efficient and versatile wired-wireless interconnect fabrics for massive heterogeneous processors. To that end, the use of graphene-based antennas and transceivers with unique frequency-beam reconfigurability in the terahertz band is proposed. The feasibility of such a wireless vision and the main research challenges towards its realization are analyzed from the technological, communications, and computer architecture perspectives
Reduction of fibrillar strain-rate sensitivity in steroid-induced osteoporosis linked to changes in mineralized fibrillar nanostructure
As bone is used in a dynamic mechanical environment, understanding the structural origins of its time-dependent mechanical behaviour – and the alterations in metabolic bone disease – is of interest. However, at the scale of the mineralized fibrillar matrix (nanometre-level), the nature of the strain-rate dependent mechanics is incompletely understood. Here, we investigate the fibrillar- and mineral-deformation behaviour in a murine model of Cushing’s syndrome, used to understand steroid induced osteoporosis, using synchrotron small- and wide-angle scattering/diffraction combined with in situ tensile testing at three strain rates ranging from 10-4 to 10-1 s-1. We find that the effective fibril- and mineral-modulus and fibrillar-reorientation show no significant increase with strain-rate in osteoporotic bone, but increase significantly in normal (wild-type) bone. By applying a fibril-lamellar two-level structural model of bone matrix deformation to fit the results, we obtain indications that altered collagen-mineral interactions at the nanoscale – along with altered fibrillar orientation distributions – may be the underlying reason for this altered strain-rate sensitivity. Our results suggest that an altered strain-rate sensitivity of the bone matrix in osteoporosis may be one of the contributing factors to reduced mechanical competence in such metabolic bone disorders, and that increasing this sensitivity may improve biomechanical performance
Dynamic Assignment and Maintenance of Positional Identity in the Ventral Neural Tube by the Morphogen Sonic Hedgehog
During development of the vertebrate neural tube, cells acquire their positional identity from not only the spatial level of the Sonic Hedgehog signaling gradient, but also the temporal duration
A Re-examination of the Portevin-Le Chatelier Effect in Alloy 718 in Connection with Oxidation-Assisted Intergranular Cracking
In Alloy 718, a sharp transition exists in the fracture path changing from an intergranular brittle mode to a transgranular ductile mode which is associated with a transition of flow behavior from smooth in the dynamic strain aging regime to a serrated one in the Portevin-Le Chatelier (PLC) regime. In order to better understand both deformation and rupture behavior, PLC phenomenon in a precipitation-hardened nickel-base superalloy was carefully investigated in a wide range of temperatures [573 K to 973 K (300°C to 700°C)] and strain rates (109^-5 to 3.2910^-2 s^-1 ). Distinction was made between two PLC domains characterized by different evolutions of the critical strain to the onset of the first serration namely normal and inverse behavior. The apparent activation energies associated with both domains were determined using different methods. Results showed that normal and inverse behavior domains are related to dynamic interaction of dislocations with, respectively, interstitial and substitutional solutes atoms. This analysis confirms that normal PLC regime may be associated to the diffusion of carbon atoms, whereas the substitutional species involves in the inverse regime is discussed with an emphasis on the role of Nb and Mo
Implementing lung cancer screening: baseline results from a community-based ‘Lung Health Check’ pilot in deprived areas of Manchester
We report baseline results of a community-based, targeted, low-dose CT (LDCT) lung cancer screening pilot in deprived areas of Manchester. Ever smokers, aged 55–74 years, were invited to ‘lung health checks’ (LHCs) next to local shopping centres, with immediate access to LDCT for those at high risk (6-year risk ≥1.51%, PLCOM2012 calculator). 75% of attendees (n=1893/2541) were ranked in the lowest deprivation quintile; 56% were high risk and of 1384 individuals screened, 3% (95% CI 2.3% to 4.1%) had lung cancer (80% early stage) of whom 65% had surgical resection. Taking lung cancer screening into communities, with an LHC approach, is effective and engages populations in deprived areas
Second round results from the Manchester ‘Lung Health Check’ community-based targeted lung cancer screening pilot
We report results from the second annual screening round (T1) of Manchester’s ‘Lung Health Check’ pilot of community-based lung cancer screening in deprived areas (undertaken June to August 2017). Screening adherence was 90% (n=1194/1323): 92% of CT scans were classified negative, 6% indeterminate and 2.5% positive; there were no interval cancers. Lung cancer incidence was 1.6% (n=19), 79% stage I, treatments included surgery (42%, n=9), stereotactic ablative radiotherapy (26%, n=5) and radical radiotherapy (5%, n=1). False-positive rate was 34.5% (n=10/29), representing 0.8% of T1 participants (n=10/1194). Targeted community-based lung cancer screening promotes high screening adherence and detects high rates of early stage lung cancer
Absence of knockdown resistance suggests metabolic resistance in the main malaria vectors of the Mekong region
<p>Abstract</p> <p>Background</p> <p>As insecticide resistance may jeopardize the successful malaria control programmes in the Mekong region, a large investigation was previously conducted in the Mekong countries to assess the susceptibility of the main malaria vectors against DDT and pyrethroid insecticides. It showed that the main vector, <it>Anopheles epiroticus</it>, was highly pyrethroid-resistant in the Mekong delta, whereas <it>Anopheles minimus sensu lato </it>was pyrethroid-resistant in northern Vietnam. <it>Anopheles dirus sensu stricto </it>showed possible resistance to type II pyrethroids in central Vietnam. <it>Anopheles subpictus </it>was DDT- and pyrethroid-resistant in the Mekong Delta. The present study intends to explore the resistance mechanisms involved.</p> <p>Methods</p> <p>By use of molecular assays and biochemical assays the presence of the two major insecticide resistance mechanisms, knockdown and metabolic resistance, were assessed in the main malaria vectors of the Mekong region.</p> <p>Results</p> <p>Two FRET/MCA assays and one PCR-RFLP were developed to screen a large number of <it>Anopheles </it>populations from the Mekong region for the presence of knockdown resistance (<it>kdr</it>), but no <it>kdr </it>mutation was observed in any of the study species. Biochemical assays suggest an esterase mediated pyrethroid detoxification in <it>An. epiroticus </it>and <it>An. subpictus </it>of the Mekong delta. The DDT resistance in <it>An. subpictus </it>might be conferred to a high GST activity. The pyrethroid resistance in <it>An. minimus s.l</it>. is possibly associated with increased detoxification by esterases and P450 monooxygenases.</p> <p>Conclusion</p> <p>As different metabolic enzyme systems might be responsible for the pyrethroid and DDT resistance in the main vectors, each species may have a different response to alternative insecticides, which might complicate the malaria vector control in the Mekong region.</p
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