Large-scale, highly integrated and low-power-consuming hardware is becoming progressively more important for realizing optical neural networks (ONNs) capable of advanced optical computing. ...Traditional experimental implementations need N
units such as Mach-Zehnder interferometers (MZIs) for an input dimension N to realize typical computing operations (convolutions and matrix multiplication), resulting in limited scalability and consuming excessive power. Here, we propose the integrated diffractive optical network for implementing parallel Fourier transforms, convolution operations and application-specific optical computing using two ultracompact diffractive cells (Fourier transform operation) and only N MZIs. The footprint and energy consumption scales linearly with the input data dimension, instead of the quadratic scaling in the traditional ONN framework. A ~10-fold reduction in both footprint and energy consumption, as well as equal high accuracy with previous MZI-based ONNs was experimentally achieved for computations performed on the MNIST and Fashion-MNIST datasets. The integrated diffractive optical network (IDNN) chip demonstrates a promising avenue towards scalable and low-power-consumption optical computational chips for optical-artificial-intelligence.
Hyperflares of M Dwarfs Chang, H.-Y.; Lin, C.-L.; Ip, W.-H. ...
The Astrophysical journal,
11/2018, Letnik:
867, Številka:
1
Journal Article
Recenzirano
From a study of the light curves of the M dwarfs observed by the Kepler space telescope in its primary mission, a number of flare events with the peak flux increases reaching more than the nominal ...stellar luminosity have been found. One of them, KIC 9201463, produced an extreme flare with the peak flux increase jumping to five times the quiet-time value. In relative terms, this class of hyperflares is much stronger than the superflares of the solar-type stars and could have a very important influence on the atmospheric evolution and the potential development of biospheres of habitable super-Earths orbiting around M dwarf stars. A cross-correlation of the flare activities of some of these M dwarf stars and their H equivalent width (EW) values derived from the LAMOST project indicates that the H EW values can be used to monitor the occurrence of hyperflares as well as the level of flare activity of different classes of M dwarfs with fast to slow rotations, and hence the long-term environmental effects of star-planet interaction of exoplanets.
The physical properties of 12 eclipsing binaries of M-type dwarfs with superflare activity are characterized by combining the ground-based spectroscopic measurements and the photometric light curves ...obtained by the Kepler Space Telescope. All of these binary systems have Algol-type orbital configurations. The primary components are mostly of the early M-type dwarfs (M0-M3). Even though the occurrence rate of large flares with energy >1034 erg of the EBs is less than the hyperflaring M dwarfs, the corresponding cumulative flare frequency is in general about a factor of 10 higher than the single M dwarfs with flare activity. This might be the consequence of magnetic interaction between the primary and secondary component of individual binaries. The slow rotators are not as active as the fast rotators, some of which display a possible eclipsing effect in their flare activity.
Abstract Previous data demonstrate that traumatic brain injury (TBI) activates autophagy, and increases microtubule-associated protein 1 light chain 3 (LC3) immunostaining mainly in neurons. However, ...the role of autophagy in traumatic brain damage remains elusive. The aim of the present study was to investigate the autophagic mechanisms participating in traumatic brain injury. The autophagy inhibitors 3-methyladenine (3-MA) and bafliomycin A1 (BFA) were administered with a single i.c.v. injection before TBI. We first examined the protein levels of Beclin-1 and LC3 II, which have been found to promote autophagy previously. Immunoblotting analysis showed that 3-MA pretreatment reduced post-TBI Beclin-1 and LC3-II levels, and maintained p62/SQSTM1 (p62) levels. In addition, double immunolabeling showed that the increased punctate LC3-II dots colocalizing with Propidium Iodide (PI)-stained nuclei at 24 h after injury, were partially inhibited by 3-MA pretreatment. Furthermore, inhibition of autophagy could reduce TBI-induced cell injury assessed with i.p. injection of PI and lesion volume, and attenuate behavioral outcome evaluated by motor test and Morris water maze. The neuroprotective effects were associated with an inhibition on TBI-induced up-regulation of LC3, Beclin-1, cathepsin B, caspase-3 and the Beclin-1/Bcl-2 ratio. Taken together, these data imply that the autophagy pathway is involved in the pathophysiologic responses after TBI, and inhibition of this pathway may help attenuate traumatic damage and functional outcome deficits.
Summary
Background Nationwide data on the epidemiology of dermatomyositis (DM) and polymyositis (PM) were limited.
Objectives This study was to estimate the incidence, occurrence of cancer and ...mortality of DM and PM in Taiwan.
Methods Both the register of critical illness of the Taiwan National Health Insurance Research Dataset and the National Death Registry of Taiwan were used to calculate estimates of the incidence, cancer association, and mortality of DM and PM between 2003 and 2007.
Results A total of 803 DM and 500 PM cases were identified between 2003 and 2007. Mean age at diagnosis was 44·0 ± 18·3 years for DM and 49·2 ± 15·9 years for PM. The overall annual incidences of DM and PM were 7·1 (95% CI 6·6–7·6) and 4·4 (95% CI 4·0–4·8) cases per million population. The incidence of both DM and PM increased with age and reached a peak at age 50–59 years. One hundred and eleven (13·8%) patients with DM and 31 (6·2%) patients with PM had cancers. The diagnosis of most cancers was made after the diagnoses of DM (n = 71; 64·0%) and PM (n = 21; 67·7%). Overall, the standardized incidence ratios (SIR) for cancer were 5·36 (4·12–6·87) and 1·80 (1·10–2·79) among patients with DM and PM; however, during the first year, SIRs for cancer were 24·55 (95% CI 18·62–31·79) and 9·17 (95% CI 14·82–15·93) in patients with DM and PM, respectively. The most common types of cancer were nasopharyngeal cancer for men and breast cancer for women. Patients with DM and PM had standardized mortality ratios of 7·68 (6·41–9·01) and 5·29 (4·28–6·48).
Conclusion This study reports robust estimates of important aspects of the epidemiology of both DM and PM in Taiwan. This highlights the rarity of these diseases, and their associated cancer risks and increased mortality.
Complex-valued neural networks have many advantages over their real-valued counterparts. Conventional digital electronic computing platforms are incapable of executing truly complex-valued ...representations and operations. In contrast, optical computing platforms that encode information in both phase and magnitude can execute complex arithmetic by optical interference, offering significantly enhanced computational speed and energy efficiency. However, to date, most demonstrations of optical neural networks still only utilize conventional real-valued frameworks that are designed for digital computers, forfeiting many of the advantages of optical computing such as efficient complex-valued operations. In this article, we highlight an optical neural chip (ONC) that implements truly complex-valued neural networks. We benchmark the performance of our complex-valued ONC in four settings: simple Boolean tasks, species classification of an Iris dataset, classifying nonlinear datasets (Circle and Spiral), and handwriting recognition. Strong learning capabilities (i.e., high accuracy, fast convergence and the capability to construct nonlinear decision boundaries) are achieved by our complex-valued ONC compared to its real-valued counterpart.
A novel coronavirus (SCoV) is the etiological agent of severe acute respiratory syndrome (SARS). SCoV-like viruses were isolated from Himalayan palm civets found in a live-animal market in Guangdong, ...China. Evidence of virus infection was also detected in other animals (including a raccoon dog, Nyctereutes procyonoides) and in humans working at the same market. All the animal isolates retain a 29-nucleotide sequence that is not found in most human isolates. The detection of SCoV-like viruses in small, live wild mammals in a retail market indicates a route of interspecies transmission, although the natural reservoir is not known.
Deformation twinning in pure aluminum has been considered to be a unique property of nanostructured aluminum. A lingering mystery is whether deformation twinning occurs in coarse-grained or ...single-crystal aluminum at scales beyond nanotwins. Here, we present the first experimental demonstration of macrodeformation twins in single-crystal aluminum formed under an ultrahigh strain rate (∼10^{6} s^{-1}) and large shear strain (200%) via dynamic equal channel angular pressing. Large-scale molecular dynamics simulations suggest that the frustration of subsonic dislocation motion leads to transonic deformation twinning. Deformation twinning is rooted in the rate dependences of dislocation motion and twinning, which are coupled, complementary processes during severe plastic deformation under ultrahigh strain rates.
Asymptomatic patients, together with those with mild symptoms of coronavirus disease 2019 (COVID-19), may play an important role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ...transmission. However, the dynamics of virus shedding during the various phases of the clinical course of COVID-19 remains unclear at this stage.
A total of 18 patients found to be positive for SARS-CoV-2 infection by real-time reverse transcription PCR (RT-PCR) assay and admitted to Chongqing University Central Hospital between 29 January and 5 February 2020 were enrolled into this study. Medical data, pulmonary computed tomographic (CT) scan images and RT-PCR results were periodically collected during the patients' hospital stay. All participants were actively followed up for 2 weeks after discharge.
A total of nine (50%) asymptomatic patients and nine (50%) patients with mild symptoms of COVID-19 were identified at admission. Six patients (66.7%) who were asymptomatic at admission developed subjective symptoms during hospitalization and were recategorized as being presymptomatic. The median duration of virus shedding was 11.5, 28 and 31 days for presymptomatic, asymptomatic and mildly symptomatic patients, separately. Seven patients (38.9%) continued to shed virus after hospital discharge. During the convalescent phase, detectable antibodies to SARS-CoV-2 and RNA were simultaneously observed in five patients (27.8%).
Long-term virus shedding was documented in patients with mild symptoms and in asymptomatic patients. Specific antibody production to SARS-CoV-2 may not guarantee virus clearance after discharge. These observations should be considered when making decisions regarding clinical and public health, and when considering strategies for the prevention and control of SARS-CoV-2 infection.
The coronavirus disease 2019 (COVID-19) pandemic has resulted in millions of patients infected worldwide and indirectly affecting even more individuals through disruption of daily living. Long-term ...adverse outcomes have been reported with similar diseases from other coronaviruses, namely Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Emerging evidence suggests that COVID-19 adversely affects different systems in the human body. This review summarizes the current evidence on the short-term adverse health outcomes and assesses the risk of potential long-term adverse outcomes of COVID-19. Major adverse outcomes were found to affect different body systems: immune system (including but not limited to Guillain-Barré syndrome and paediatric inflammatory multisystem syndrome), respiratory system (lung fibrosis and pulmonary thromboembolism), cardiovascular system (cardiomyopathy and coagulopathy), neurological system (sensory dysfunction and stroke), as well as cutaneous and gastrointestinal manifestations, impaired hepatic and renal function. Mental health in patients with COVID-19 was also found to be adversely affected. The burden of caring for COVID-19 survivors is likely to be huge. Therefore, it is important for policy makers to develop comprehensive strategies in providing resources and capacity in the healthcare system. Future epidemiological studies are needed to further investigate the long-term impact on COVID-19 survivors.
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