149 research outputs found
Distributed Training Large-Scale Deep Architectures
Scale of data and scale of computation infrastructures together enable the
current deep learning renaissance. However, training large-scale deep
architectures demands both algorithmic improvement and careful system
configuration. In this paper, we focus on employing the system approach to
speed up large-scale training. Via lessons learned from our routine
benchmarking effort, we first identify bottlenecks and overheads that hinter
data parallelism. We then devise guidelines that help practitioners to
configure an effective system and fine-tune parameters to achieve desired
speedup. Specifically, we develop a procedure for setting minibatch size and
choosing computation algorithms. We also derive lemmas for determining the
quantity of key components such as the number of GPUs and parameter servers.
Experiments and examples show that these guidelines help effectively speed up
large-scale deep learning training
ECG Signal Super-resolution by Considering Reconstruction and Cardiac Arrhythmias Classification Loss
With recent advances in deep learning algorithms, computer-assisted
healthcare services have rapidly grown, especially for those that combine with
mobile devices. Such a combination enables wearable and portable services for
continuous measurements and facilitates real-time disease alarm based on
physiological signals, e.g., cardiac arrhythmias (CAs) from electrocardiography
(ECG). However, long-term and continuous monitoring confronts challenges
arising from limitations of batteries, and the transmission bandwidth of
devices. Therefore, identifying an effective way to improve ECG data
transmission and storage efficiency has become an emerging topic. In this
study, we proposed a deep-learning-based ECG signal super-resolution framework
(termed ESRNet) to recover compressed ECG signals by considering the joint
effect of signal reconstruction and CA classification accuracies. In our
experiments, we downsampled the ECG signals from the CPSC 2018 dataset and
subsequently evaluated the super-resolution performance by both reconstruction
errors and classification accuracies. Experimental results showed that the
proposed ESRNet framework can well reconstruct ECG signals from the 10-times
compressed ones. Moreover, approximately half of the CA recognition accuracies
were maintained within the ECG signals recovered by the ESRNet. The promising
results confirm that the proposed ESRNet framework can be suitably used as a
front-end process to reconstruct compressed ECG signals in real-world CA
recognition scenarios
Early Low-Titer Neutralizing Antibodies Impede HIV-1 Replication and Select for Virus Escape
Single genome sequencing of early HIV-1 genomes provides a sensitive, dynamic assessment of virus evolution and insight into the earliest anti-viral immune responses in vivo. By using this approach, together with deep sequencing, site-directed mutagenesis, antibody adsorptions and virus-entry assays, we found evidence in three subjects of neutralizing antibody (Nab) responses as early as 2 weeks post-seroconversion, with Nab titers as low as 1βΆ20 to 1βΆ50 (IC50) selecting for virus escape. In each of the subjects, Nabs targeted different regions of the HIV-1 envelope (Env) in a strain-specific, conformationally sensitive manner. In subject CH40, virus escape was first mediated by mutations in the V1 region of the Env, followed by V3. HIV-1 specific monoclonal antibodies from this subject mapped to an immunodominant region at the base of V3 and exhibited neutralizing patterns indistinguishable from polyclonal antibody responses, indicating V1βV3 interactions within the Env trimer. In subject CH77, escape mutations mapped to the V2 region of Env, several of which selected for alterations of glycosylation. And in subject CH58, escape mutations mapped to the Env outer domain. In all three subjects, initial Nab recognition was followed by sequential rounds of virus escape and Nab elicitation, with Nab escape variants exhibiting variable costs to replication fitness. Although delayed in comparison with autologous CD8 T-cell responses, our findings show that Nabs appear earlier in HIV-1 infection than previously recognized, target diverse sites on HIV-1 Env, and impede virus replication at surprisingly low titers. The unexpected in vivo sensitivity of early transmitted/founder virus to Nabs raises the possibility that similarly low concentrations of vaccine-induced Nabs could impair virus acquisition in natural HIV-1 transmission, where the risk of infection is low and the number of viruses responsible for transmission and productive clinical infection is typically one
Discovery of Isoplumbagin as a Novel NQO1 Substrate and Anti-Cancer Quinone
Isoplumbagin (5-hydroxy-3-methyl-1,4-naphthoquinone), a naturally occurring quinone from Lawsonia inermis and Plumbago europaea, has been reported to have anti-inflammatory and antimicrobial activity. Inflammation has long been implicated in cancer progression. In this study, we examined the anticancer effect of chemically synthesized isoplumbagin. Our results revealed that isoplumbagin treatment suppressed cell viability and invasion of highly invasive oral squamous cell carcinoma (OSCC) OC3-IV2 cells, glioblastoma U87 cells, non-small cell lung carcinoma H1299 cells, prostate cancer PC3 cells, and cervical cancer HeLa cells by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Boyden chamber assays. In vivo studies demonstrate the inhibitory effect of 2 mg/kg isoplumbagin on the growth of orthotopic xenograft tumors derived from OSCC cells. Mechanistically, isoplumbagin exerts its cytotoxic effect through acting as a substrate of reduced nicotinamide adenine dinucleotide phosphate [NAD(P)H] dehydrogenase quinone 1 (NQO1) to generate hydroquinone, which reverses mitochondrial fission phenotype, reduces mitochondrial complex IV activity, and thus compromises mitochondrial function. Collectively, this work reveals an anticancer activity of isoplumbagin mainly through modulating mitochondrial dynamics and function
Subacute bacterial endocarditis presenting as left upper quadrant abdominal pain
Infective endocarditis is a microbial infection of the endocardial surface of the heart. Its symptoms and signs are varied, and include fever, heart murmur, peripheral embolism, and heart failure. The diagnosis of subacute bacterial endocarditis (SBE) is suggested by a history of an indolent process characterized by fever, fatigue, anorexia, and unexplained weight loss. These patients may have had an invasive procedure, such as dental work, or abused intravenous drugs prior to the diagnosis of SBE. Although uncommon, the patients may present with nonspecific symptoms caused by peripheral embolic events. Herein, we report a 25-year-old male diagnosed with SBE, who presented with the unusual symptom of sudden onset of left upper quadrant abdominal pain for 2 days. His clinical history is also discussed
New Low-Voltage Driving Compensating Pixel Circuit Based on High-Mobility Amorphous Indium-Zinc-Tin-Oxide Thin-Film Transistors for High-Resolution Portable Active-Matrix OLED Displays
In recent years, active-matrix organic light-emitting diodes (AMOLEDs) has been the most popular display for portable application. To satisfy the requirement for the application of the portable display, the design of the compensating pixel circuit with the low-voltage driving and low-power consumption will be requested. In addition to the circuit with the design of the low-voltage driving, high-mobility thin-film transistors as driving device will be also necessary in order to supply larger driving current at low-voltage driving. Therefore, the study presents a new low-voltage driving AMOLED pixel circuit with high-mobility amorphous indium–zinc–tin–oxide (a-IZTO) thin-film transistors (TFTs) as driving device for portable displays with high resolution. The proposed pixel circuit can simultaneously compensate for the threshold voltage variation of driving TFT (ΔVTH_TFT), OLED degradation (ΔVTH_OLED), and the I-R drop of a power line (ΔVDD). By using AIM-Spice for simulation based on fabricated a-IZTO TFTs with mobility of 70 cm2V−1S−1 as driving devices, we discovered that the error rates of the driving current were all lower than 5.71% for all input data when ΔVTH_TFT = ±1 V, ΔVDD = 0.5 V, and ΔVTH_OLED = 0.5 V were all considered simultaneously. We revealed that the proposed 5T2C pixel circuit containing a high-mobility a-IZTO TFT as a driving device was suitable for high-resolution portable displays
Differential Immunogenicity of Two Peptides Isolated by High Molecular Weight-Melanoma-Associated Antigen-Specific Monoclonal Antibodies with Different Affinities
Atrioventricular conduction abnormality and hyperchloremic metabolic acidosis in toluene sniffing
Toluene is an aromatic hydrocarbon with widespread industrial use as an organic solvent. As a result of the euphoric effect and availability of these substances, inhalation of toluene-based products is popular among young adults and children. Chronic or acute exposure is known to cause acidβbase and electrolyte disorders, and to be toxic to the nervous and hematopoietic systems. We report a 38-year-old man who suffered from general muscular weakness of all extremities after toluene sniffing, which was complicated with hypokalemic paralysis, atrioventricular conduction abnormality, and normal anion gap hyperchloremic metabolic acidosis. Renal function, serum potassium and acidβbase status normalized within 3 days after aggressive potassium chloride and intravenous fluid replacement. Electrocardiography showed regression of first-degree atrioventricular block. Exposure to toluene can lead to cardiac arrhythmias and sudden sniffing death syndrome. Tachyarrhythmia is the classical manifestation of toluene cardiotoxicity. Atrioventricular conduction abnormalities have been rarely mentioned in the literature. Knowledge of the toxicology and medical complications associated with toluene sniffing is essential for clinical management of these patients
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