168 research outputs found
MergeSFL: Split Federated Learning with Feature Merging and Batch Size Regulation
Recently, federated learning (FL) has emerged as a popular technique for edge
AI to mine valuable knowledge in edge computing (EC) systems. To mitigate the
computing/communication burden on resource-constrained workers and protect
model privacy, split federated learning (SFL) has been released by integrating
both data and model parallelism. Despite resource limitations, SFL still faces
two other critical challenges in EC, i.e., statistical heterogeneity and system
heterogeneity. To address these challenges, we propose a novel SFL framework,
termed MergeSFL, by incorporating feature merging and batch size regulation in
SFL. Concretely, feature merging aims to merge the features from workers into a
mixed feature sequence, which is approximately equivalent to the features
derived from IID data and is employed to promote model accuracy. While batch
size regulation aims to assign diverse and suitable batch sizes for
heterogeneous workers to improve training efficiency. Moreover, MergeSFL
explores to jointly optimize these two strategies upon their coupled
relationship to better enhance the performance of SFL. Extensive experiments
are conducted on a physical platform with 80 NVIDIA Jetson edge devices, and
the experimental results show that MergeSFL can improve the final model
accuracy by 5.82% to 26.22%, with a speedup by about 1.74x to 4.14x, compared
to the baselines
Examining the Relations among Student Motivation, Engagement, and Retention in a MOOC: A Structural Equation Modeling Approach
Students who are enrolled in MOOCs tend to have different motivational patterns than fee-paying college students. A majority of MOOC students demonstrate characteristics akin more to "tourists" than formal learners. As a consequence, MOOC studentsΓÇÖ completion rate is usually very low. The current study examines the relations among student motivation, engagement, and retention using structural equation modeling and data from a Penn State University MOOC. Three distinct types of motivation are examined: intrinsic motivation, extrinsic motivation, and social motivation. Two main hypotheses are tested: (a) motivation predicts student course engagement; and (b) student engagement predicts their retention in the course. The results show that motivation is significantly predictive of student course engagement. Furthermore, engagement is a strong predictor of retention. The findings suggest that promoting student motivation and monitoring individual studentsΓÇÖ online activities might improve course retention
Purification and characterization of three laccase isozymes from the white rot fungus Trametes sp. HS-03
Three laccase isozymes (LacI, LacII and LacIII) were isolated from the culture supernatant solution of Trametes sp. HS-03. Diethylaminoethyl (DEAE)-sepharose fast flow anion exchange chromatography and Sephadex G-100 size-exclusion chromatography was performed to achieve electrophoretic homogeneity. The molecular masses (64.2, 60.7 and 38.9 kDa), isoelectric points [pIs (7.3, 4.7 and 3.5), and N-terminal amino acid sequences (G-I-G-P-V, A-I-G-P-T and S-I-G-P-V) were found to be different for the three laccase isozymes. LacI and II have similar thermostability, while LacIII showed better thermostability. LacIII also showed optimal activity at 80°C, with a half-life of 125 min at 70°C. The pI-value of LacI and the molecular mass of LacIII differ significantly from previously described fungal laccases.Keywords: Trametes sp. HS-03, laccase isozymes, purification, characterizatio
Pretreatment Level of Red Cell Distribution Width as a Prognostic Indicator for Survival in a Large Cohort Study of Male Laryngeal Squamous Carcinoma
Objective: High levels of red cell distribution width (RDW) may be associated with adverse outcomes in patients with cancer. The purpose of the present study was to investigate the prognostic impact of pretreatment RDW levels on overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS) in a large cohort of male laryngeal squamous cell cancer (LSCC) patients.Methods: A total of 809 LSCC patients who were treated between 2007 and 2011 at the Eye & ENT Hospital of Fudan University were enrolled and evaluated retrospectively. OS, CSS, and DFS were analyzed using the Kaplan–Meier method. To evaluate the prognostic significance of RDW levels, univariate, and multivariate Cox analyses were applied.Results: Higher pretreatment RDW levels were significantly associated with high death events, red blood cell count, hemoglobin, radiotherapy, operation therapy, and advanced tumor stage (p < 0.05). From the univariate analysis, we observed that the higher (13.2–13.5%) and the highest (>13.5%) quartiles of RDW level were consistent factors for poor OS, CSS, and DFS in LSCC patients. In the multivariate analysis, after adjusting for confounding factors, the higher and highest quartiles of RDW levels were identified as independent prognostic factors in male LSCC patients.Conclusion: Higher pretreatment RDW levels were demonstrated to be associated with poor clinical outcome in male LSCC patients and might be novel markers for patient stratification in LSCC management
Acute Toxicity, Antioxidant, and Antifatigue Activities of Protein-Rich Extract from Oviductus ranae
The paper investigated the preparation, amino acid composition, acute toxicity, and in vitro and in vivo antioxidant, coupled with in vivo antifatigue activities of protein-rich extract of Oviductus ranae (PEOR). The results indicated that PEOR possesses high-safety property with maximum tolerated dose (MTD) higher than 20 g/kg in mice, shows weak scavenging capacities against hydroxyl, superoxide anion, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, as well as ferric-reducing antioxidant power in vitro, but exerts strong antioxidant effect in ethanol-induced oxidative stress mice model; it can decrease malonaldehyde (MDA) and protein carbonyl (PCO) formation and increase total superoxide dismutase (T-SOD) activity and glutathione (GSH) synthesis. Besides the strong in vivo antioxidant activity, PEOR in a dose of 400 mg/kg also has antifatigue effect in mice, and it can prolong the exhaustive swimming time, reduce the elevated blood urea nitrogen (BUN) and blood lactic acid (BLA) caused by intense exercise. The in vivo activity of PEOR may be contributed by its absorbed amino acids, due to the fact that eight antioxidant amino acids and twelve glucogenic ones were found in it. This study will provide an evidence for the clinical use of PEOR as a dietary supplement for antioxidant and antifatigue in the same oral dose (400 mg/kg)
Co-infusion of haplo-identical CD19-chimeric antigen receptor T cells and stem cells achieved full donor engraftment in refractory acute lymphoblastic leukemia
Abstract Background Elderly patients with relapsed and refractory acute lymphoblastic leukemia (ALL) have poor prognosis. Autologous CD19 chimeric antigen receptor-modified T (CAR-T) cells have potentials to cure patients with B cell ALL; however, safety and efficacy of allogeneic CD19 CAR-T cells are still undetermined. Case presentation We treated a 71-year-old female with relapsed and refractory ALL who received co-infusion of haplo-identical donor-derived CD19-directed CAR-T cells and mobilized peripheral blood stem cells (PBSC) following induction chemotherapy. Undetectable minimal residual disease by flow cytometry was achieved, and full donor cell engraftment was established. The transient release of cytokines and mild fever were detected. Significantly elevated serum lactate dehydrogenase, alanine transaminase, bilirubin and glutamic-oxalacetic transaminase were observed from days 14 to 18, all of which were reversible after immunosuppressive therapy. Conclusions Our preliminary results suggest that co-infusion of haplo-identical donor-derived CAR-T cells and mobilized PBSCs may induce full donor engraftment in relapsed and refractory ALL including elderly patients, but complications related to donor cell infusions should still be cautioned. Trial registration Allogeneic CART-19 for Elderly Relapsed/Refractory CD19+ ALL. NCT0279955
Achieving high-efficiency conversion and poly-generation of cooling, heating, and power based on biomass-fueled SOFC hybrid system : performance assessment and multi-objective optimization
Abstract: In order to develop clean and efficient energy conversion technology, a novel combined cooling, heating and power (CCHP) system using biomass as fuel is proposed in this work. The proposed CCHP system consists of biomass gasification unit, solid oxide fuel cell (SOFC) and engine power generation unit and absorption refrigeration unit. Thermodynamic model of the CCHP system is developed for the parametric and exergy analyses to evaluate the performance. The parametric analysis shows that increasing the steam to biomass ratio or the SOFC fuel utilization factor helps to improve the electrical efficiency, while the increase of air equivalent ratio has a negative effect. The exergy analysis shows that the two units of biomass gasification and engine power generation have the largest exergy destruction ratio, which is 46.9% and 16.8% under the biomass flux of 500 kg·h -1 . This is because these two units involve in high-temperature thermochemical reaction process, resulting in relatively large exergy destruction. Besides, the tradeoff between maximum exergy efficiency, CCHP efficiency and minimum total annual cost is conducted by multi-objective optimization. Through optimization, the system could reach the high CCHP efficiency of 75 % and net electrical efficiency of 52%, as well as the low total annual cost of 410 k$ simultaneously. This work could provide the basic design idea, and high-efficiency and low-cost operation strategy for the practical application of the proposed novel biomassfueled CCHP poly-generation system
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