600 research outputs found
GNNPipe: Scaling Deep GNN Training with Pipelined Model Parallelism
Communication is a key bottleneck for distributed graph neural network (GNN)
training. This paper proposes GNNPipe, a new approach that scales the
distributed full-graph deep GNN training. Being the first to use layer-level
model parallelism for GNN training, GNNPipe partitions GNN layers among GPUs,
each device performs the computation for a disjoint subset of consecutive GNN
layers on the whole graph. Compared to graph parallelism with each GPU handling
a graph partition, GNNPipe reduces the communication volume by a factor of the
number of GNN layers. GNNPipe overcomes the unique challenges for pipelined
layer-level model parallelism on the whole graph by partitioning it into
dependent chunks, allowing the use of historical vertex embeddings, and
applying specific training techniques to ensure convergence. We also propose a
hybrid approach by combining GNNPipe with graph parallelism to handle large
graphs, achieve better computer resource utilization and ensure model
convergence. We build a general GNN training system supporting all three
parallelism setting. Extensive experiments show that our method reduces the
per-epoch training time by up to 2.45x (on average 1.58x) and reduces the
communication volume and overhead by up to 22.89x and 27.21x (on average 8.69x
and 11.60x), respectively, while achieving a comparable level of model accuracy
and convergence speed compared to graph parallelism
Quark: A Gradient-Free Quantum Learning Framework for Classification Tasks
As more practical and scalable quantum computers emerge, much attention has
been focused on realizing quantum supremacy in machine learning. Existing
quantum ML methods either (1) embed a classical model into a target Hamiltonian
to enable quantum optimization or (2) represent a quantum model using
variational quantum circuits and apply classical gradient-based optimization.
The former method leverages the power of quantum optimization but only supports
simple ML models, while the latter provides flexibility in model design but
relies on gradient calculation, resulting in barren plateau (i.e., gradient
vanishing) and frequent classical-quantum interactions. To address the
limitations of existing quantum ML methods, we introduce Quark, a gradient-free
quantum learning framework that optimizes quantum ML models using quantum
optimization. Quark does not rely on gradient computation and therefore avoids
barren plateau and frequent classical-quantum interactions. In addition, Quark
can support more general ML models than prior quantum ML methods and achieves a
dataset-size-independent optimization complexity. Theoretically, we prove that
Quark can outperform classical gradient-based methods by reducing model query
complexity for highly non-convex problems; empirically, evaluations on the Edge
Detection and Tiny-MNIST tasks show that Quark can support complex ML models
and significantly reduce the number of measurements needed for discovering
near-optimal weights for these tasks.Comment: under revie
Preparation of antibacterial microfibre
Three different kinds of antibacterial microfibres (270D, 300D and 330D) have been developed by adding 2-4 wt % nano silver masterbatch in the melt spinning process. The mechanical properties, silver content and morphology have been examined with tensile tester, inductively coupled plasma-optical emission spectrometer and scanning electron microscope respectively. Their antibacterial abilities are also studied with KS K 0693:2011. The results show that the added nano-particles have little influence on mechanical properties of antibacterial microfibres and their max strain and tenacity are similar to that of common manmade fibre. The fineness of the 270D, 300D and 330D samples are found to be 0.23, 0.26 and 0.30 den, and the corresponding added silver contents are 265.5, 231 and 259 ppm respectively. It is also observed that all samples bacteriostatic reduction rates are about 99.9% for both Staphylococcus aureus and Klebsiella pneumonia before washing. But after washing, it drops to 65.4%/75%, 91.9%/97.7% and 94.8%/99.9% respectively for both the bacteria in case of 270D, 300D and 330D samples. It is concluded that 300D and 330D microfibre samples have good antibacterial ability before and after washing
Radix Astragali
A previous study conducted by our group demonstrated that Radix Astragali compounded with Codonopsis pilosula and Plastrum testudinis was effective in treating pediatric ÎČ-thalassemia in a randomized, controlled clinical trial. However, the mechanism of action that underpins this treatment remains to be elucidated. Blood was collected from patients participating in this clinical trial and nucleated red blood cell-enriched mononuclear cells were isolated to facilitate the extraction of RNA and protein. RT-PCR was used to monitor the expression of globin genes and p38 MAPK, and total and phosphorylated p38 MAPK expression was assessed using Western blot analysis. Expression of α-, ÎČ-, and AÎł-globin mRNAs was not significantly affected following treatment with R. Astragali or the compounded formulation. However, GÎł-globin mRNA levels increased significantly in both treatment groups (when compared with pretreatment levels) following 12 weeks of treatment. Moreover, posttreatment GÎł-globin expression was significantly higher in both treatment groups compared with the control group. Although neither p38 MAPK mRNA nor protein levels were affected by the treatments, posttreatment phosphorylation of p38 MAPK was significantly increased in the R. Astragali and compounded formulation groups compared with the control group. These data suggest that the molecular mechanisms that underpin the efficacious use of R. Astragali (and its compounded formulation) in pediatric ÎČ-thalassemia treatment facilitate the induction of GÎł-globin expression following activation of p38 MAPK
Machine learning for the prediction of cognitive impairment in older adults
ObjectiveThe purpose of this study was to develop and validate a predictive model of cognitive impairment in older adults based on a novel machine learning (ML) algorithm.MethodsThe complete data of 2,226 participants aged 60â80 years were extracted from the 2011â2014 National Health and Nutrition Examination Survey database. Cognitive abilities were assessed using a composite cognitive functioning score (Z-score) calculated using a correlation test among the Consortium to Establish a Registry for Alzheimer's Disease Word Learning and Delayed Recall tests, Animal Fluency Test, and the Digit Symbol Substitution Test. Thirteen demographic characteristics and risk factors associated with cognitive impairment were considered: age, sex, race, body mass index (BMI), drink, smoke, direct HDL-cholesterol level, stroke history, dietary inflammatory index (DII), glycated hemoglobin (HbA1c), Patient Health Questionnaire-9 (PHQ-9) score, sleep duration, and albumin level. Feature selection is performed using the Boruta algorithm. Model building is performed using ten-fold cross-validation, machine learning (ML) algorithms such as generalized linear model (GLM), random forest (RF), support vector machine (SVM), artificial neural network (ANN), and stochastic gradient boosting (SGB). The performance of these models was evaluated in terms of discriminatory power and clinical application.ResultsThe study ultimately included 2,226 older adults for analysis, of whom 384 (17.25%) had cognitive impairment. After random assignment, 1,559 and 667 older adults were included in the training and test sets, respectively. A total of 10 variables such as age, race, BMI, direct HDL-cholesterol level, stroke history, DII, HbA1c, PHQ-9 score, sleep duration, and albumin level were selected to construct the model. GLM, RF, SVM, ANN, and SGB were established to obtain the area under the working characteristic curve of the test set subjects 0.779, 0.754, 0.726, 0.776, and 0.754. Among all models, the GLM model had the best predictive performance in terms of discriminatory power and clinical application.ConclusionsML models can be a reliable tool to predict the occurrence of cognitive impairment in older adults. This study used machine learning methods to develop and validate a well performing risk prediction model for the development of cognitive impairment in the elderly
Does sacubitril/valsartan work in children with heart failure?âa pilot study
BackgroundSacubitril/valsartan is an angiotensin receptor neprilysin antagonist (ARNI) approved for adult heart failure (HF). Its safety and efficacy in pediatric HF patients with cardiomyopathy or congenital heart disease are poorly understood. A pilot study was conducted to assess the clinical response, efficacy and safety of sacubitril/valsartan in this population at a tertiary care hospital in China.MethodsClinical parameters of patients who received sacubitril/valsartan from January 2019 to March 2023 were retrospectively collected and analyzed. Children over 1 month with a left ventricular ejection fraction (LVEF) <45% were included. Clinical efficacy was evaluated by echocardiographic LVEF, N-terminal pro-brain natriuretic peptide (NT-proBNP), New York Heart Association (NYHA) HF classification, HF re-admission, and death or transplantation. The initial dose was either 0.2â
mg/kg bid or 0.4â
mg/kg bid, with a target dose of 2.3â
mg/kg bid or 3.1â
mg/kg bid.ResultsForty-five patients (60% male) with a median age of 7.86 years were enrolled. Among them, 23 had congenital heart disease and 22 had cardiomyopathies. The median maintenance dose was 0.76â
mg/kg. The primary endpoint of LVEF up to 45% was reached by 24 patients (53.3%). The median NT-proBNP was significantly decreased from 5,501.5â
pg/ml to 2,241.5â
pg/ml (Pâ<â0.001), more in congenital heart disease than in cardiomyopathies (Pâ=â0.032). The NYHA HF class was improved or remained stable in 42 cases (93.3%). During a median follow-up of 1.23 years, 13 patients (28.9%) were re-hospitalized due to HF, and 9 patients (20%) died or underwent transplantation. Hypotension was the main adverse event, occurring in 8 patients.ConclusionsSacubitril/valsartan may be effective in children with HF, but its safety and outcomes may differ depending on the etiology and anatomy of HF. Early post-operative congenital heart disease patients had less tolerance, more hypotension but better recovery and outcomes, while mid- and late- post-operative congenital heart disease patients and cardiomyopathy patients had less side effects but poorer clinical outcomes
Measurement of the B0sâÎŒ+ÎŒâ Branching Fraction and Effective Lifetime and Search for B0âÎŒ+ÎŒâ Decays
A search for the rare decays Bs0âÎŒ+ÎŒ- and B0âÎŒ+ÎŒ- is performed at the LHCb experiment using data collected in pp collisions corresponding to a total integrated luminosity of 4.4ââfb-1. An excess of Bs0âÎŒ+ÎŒ- decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(Bs0âÎŒ+ÎŒ-)=(3.0±0.6-0.2+0.3)Ă10-9, where the first uncertainty is statistical and the second systematic. The first measurement of the Bs0âÎŒ+ÎŒ- effective lifetime, Ï(Bs0âÎŒ+ÎŒ-)=2.04±0.44±0.05ââps, is reported. No significant excess of B0âÎŒ+ÎŒ- decays is found, and a 95% confidence level upper limit, B(B0âÎŒ+ÎŒ-)<3.4Ă10-10, is determined. All results are in agreement with the standard model expectations.A search for the rare decays and is performed at the LHCb experiment using data collected in collisions corresponding to a total integrated luminosity of 4.4 fb. An excess of decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be , where the first uncertainty is statistical and the second systematic. The first measurement of the effective lifetime, ps, is reported. No significant excess of decays is found and a 95 % confidence level upper limit, , is determined. All results are in agreement with the Standard Model expectations
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