This paper proposes a comprehensive framework for multiobjective design optimization of switched reluctance motors (SRMs) based on a combination of the design of experiments and particle swarm ...optimization (PSO) approaches. First, the definitive screening design was employed to perform sensitivity analyses to identify significant design variables without bias of interaction effects between design variables. Next, optimal third-order response surface (RS) models were constructed based on the Audze-Eglais Latin hypercube design using the selected significant design variables. The constructed optimal RS models consist of only significant regression terms, which were selected by using PSO. Then, a PSO-based multiobjective optimization coupled with the constructed RS models, instead of the finite-element analysis, was performed to generate the Pareto front with a significantly reduced computational cost. A sample SRM design with multiple optimization objectives, i.e., maximizing torque per active mass, maximizing efficiency, and minimizing torque ripple, was conducted to verify the effectiveness of the proposed optimal design framework.
Noisy matrix completion aims at estimating a low-rank matrix given only partial and corrupted entries. Despite remarkable progress in designing efficient estimation algorithms, it remains largely ...unclear how to assess the uncertainty of the obtained estimates and how to perform efficient statistical inference on the unknown matrix (e.g., constructing a valid and short confidence interval for an unseen entry). This paper takes a substantial step toward addressing such tasks. We develop a simple procedure to compensate for the bias of the widely used convex and nonconvex estimators. The resulting debiased estimators admit nearly precise nonasymptotic distributional characterizations, which in turn enable optimal construction of confidence intervals/regions for, say, the missing entries and the low-rank factors. Our inferential procedures do not require sample splitting, thus avoiding unnecessary loss of data efficiency. As a byproduct, we obtain a sharp characterization of the estimation accuracy of our debiased estimators in both rate and constant. Our debiased estimators are tractable algorithms that provably achieve full statistical efficiency.
One-part geopolymer similar to conventional Portland cement by just adding water is a new type of green cementitious material. Na2SiO3-anhydrous is an excellent powder activator for preparing ...one-part geopolymer, but its CO2-e emission and alkalinity are very high. In this study, the Na2CO3 was used to replace a portion of Na2SiO3-anhydrous, and the properties of one-part geopolymer with composite activators were investigated systematically. The possible influencing mechanism of the complex use of activators in one-part geopolymer was proposed. Test results indicate that the replacement level of Na2CO3 has slight impact on the fluidity and increases the final setting time significantly. This is directly related to the initial heat release rate and the type of network structures formed. The compressive strength decreases with increasing the Na2CO3 content. On the one hand, the quantity of gelatinous products reduces and calcite is produced as the new phase after replacing Na2SiO3-anhydrous by Na2CO3. On the other hand, the gathering of calcite and low-crystalline CaCO3 in some regions leads to the generation of many large micro-cracks, which explains the change in the porosity of the unfavorable pores. Judged from the cost per MPa and total CO2-e emission for a cubic meter of cementitious materials, one-part geopolymer activated by composite activators is cleaner than that activated by single Na2SiO3-anhydrous or Na2CO3. This study provides a guidance for preparing one-part geopolymer with lower alkalinity and potential environmental impact.
•One-part geopolymer was prepared by using the compound activator of Na2SiO3-anhydrous and Na2CO3.•The properties of one-part geopolymer and influencing mechanism of Na2CO3 were investigated.•Na2CO3 makes one-part geopolymer cleaner without sacrificing the performance and economic benefit.
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•Reviewed sewage sludge production, characteristics and application in construction materials.•Sewage sludge (≤ 15%) can replace raw material in eco-cement production with similar ...mechanical performance.•Sewage sludge (≤ 20%) substitution produces good quality bricks, ceramic materials, lightweight aggregates, and SCMs.•Sewage sludge addition decreases mechanical strength of concrete (30–50%) and increases water absorption of brick.•Heavy metals in sewage sludge become immobilized during sintering process.
With increasing amount of sewage sludge becoming an urgent and inevitable issue for every country, its applications in the production of construction and building materials provide an alternative solution for sludge disposal and resource recovery. Similar to clay and Portland cement, the main oxides in sewage sludge are SiO2 (10–25 %), Al2O3 (5–10 %) and CaO (10–30 %) which are increased in sludge ash after incineration to 25–50 %, 10–20 % and 15–30 %. Therefore, this solid waste can be utilized not only as raw material for the production of eco-cement, bricks, ceramic materials and lightweight aggregates through sintering process, but also as supplementary admixtures in cementitious materials such as pozzolanic component, fine aggregate or filling material. By critically reviewing current utilizations of sewage sludge, it is feasible to replace up to 15 % natural raw materials with sewage sludge in cement production and the manufactured eco-cement clinkers show comparable performance to traditional Portland cement. Whilst as raw feed in the fabrication of bricks, ceramic materials and lightweight aggregates, 20 % of sewage sludge substitution is acceptable to produce good quality products (within 8 % firing shrinkage and 15 % water absorption). Though high content of organic matter in raw sludge causes a decrease in mechanical strength and delay in hydration process, controlled low-strength materials offer an innovative reuse with large amount of sludge. The immobilization of heavy metals in products prevents sewage sludge causing secondary environmental pollution. Furthermore, suggestions for future research are proposed in order to strengthen the high value-added applications of sewage sludge.
The gut microbiota is crucial in the pathogenesis of type 2 diabetes mellitus (T2DM). However, the metabolism of T2DM patients is not well-understood. We aimed to identify the differences on ...composition and function of gut microbiota between T2DM patients with obesity and healthy people. In this study, 6 T2DM patients with obesity and 6 healthy volunteers were recruited, and metagenomic approach and bioinformatics analysis methods were used to understand the composition of the gut microbiota and the metabolic network. We found a decrease in the abundance of Firmicutes, Oribacterium, and Paenibacillus; this may be attributed to a possible mechanism and biological basis of T2DM; moreover, we identified three critical bacterial taxa, Bacteroides plebeius, Phascolarctobacterium sp. CAG207, and the order Acidaminococcales that can potentially be used for T2DM treatment. We also revealed the composition of the microbiota through functional annotation based on multiple databases and found that carbohydrate metabolism contributed greatly to the pathogenesis of T2DM. This study helps in elucidating the different metabolic roles of microbes in T2DM patients with obesity.
We use simulated Hubble parameter data in the redshift range 0 <= z <= 2 to explore the role and power of observational H(z) data in constraining cosmological parameters of the Delta *LCDM model. The ...error model of the simulated data is empirically constructed from available measurements and scales linearly as z increases. By comparing the median figures of merit calculated from simulated data sets with that of current Type Ia supernova (SNIa) data, we find that as many as 64 further independent measurements of H(z) are needed to match the parameter constraining power of SNIa. If the error of H(z) could be lowered to 3%, the same number of future measurements would be needed, but then the redshift coverage would only be required to reach z = 1. We also show that accurate measurements of the Hubble constant H 0 can be used as priors to increase the H(z) data's figure of merit.
The transition of the Munc18-1/syntaxin-1 complex to the SNARE complex, a key step involved in exocytosis, is regulated by Munc13-1, SNAP-25 and synaptobrevin-2, but the underlying mechanism remains ...elusive. Here, we identify an interaction between Munc13-1 and the membrane-proximal linker region of synaptobrevin-2, and reveal its essential role in transition and exocytosis. Upon this interaction, Munc13-1 not only recruits synaptobrevin-2-embedded vesicles to the target membrane but also renders the synaptobrevin-2 SNARE motif more accessible to the Munc18-1/syntaxin-1 complex. Afterward, the entry of SNAP-25 leads to a half-zippered SNARE assembly, which eventually dissociates the Munc18-1/syntaxin-1 complex to complete SNARE complex formation. Our data suggest that Munc18-1 and Munc13-1 together serve as a functional template to orchestrate SNARE complex assembly.
Synaptotagmin-1 (Syt1) acts as a Ca(2+) sensor for neurotransmitter release through its C2 domains. It has been proposed that Syt1 promotes SNARE-dependent fusion mainly through its C2B domain, but ...the underlying mechanism is poorly understood. In this study, we show that the C2B domain interacts simultaneously with acidic membranes and SNARE complexes via the top Ca(2+)-binding loops, the side polybasic patch, and the bottom face in response to Ca(2+). Disruption of the simultaneous interactions completely abrogates the triggering activity of the C2B domain in liposome fusion. We hypothesize that the simultaneous interactions endow the C2B domain with an ability to deform local membranes, and this membrane-deformation activity might underlie the functional significance of the Syt1 C2B domain in vivo.
During the priming step that leaves synaptic vesicles ready for neurotransmitter release, the SNARE syntaxin-1 transitions from a closed conformation that binds Munc18-1 tightly to an open ...conformation within the highly stable SNARE complex. Control of this conformational transition is important for brain function, but the underlying mechanism is unknown. NMR and fluorescence experiments now show that the Munc13-1 MUN domain, which plays a central role in vesicle priming, markedly accelerates the transition from the syntaxin-1-Munc18-1 complex to the SNARE complex. This activity depends on weak interactions of the MUN domain with the syntaxin-1 SNARE motif, and probably with Munc18-1. Together with available physiological data, these results provide a defined molecular basis for synaptic vesicle priming, and they illustrate how weak protein-protein interactions can play crucial biological roles by promoting transitions between high-affinity macromolecular assemblies.
The purpose of this study was to analyze the clinical and electrographic characteristics of seizures in LGI1-antibody encephalitis.
The methods utilized in this study were prospective analysis of the ...clinical manifestations, types of seizures, electroencephalogram (EEG), adjuvant examination, treatment and prognosis of 19 cases of LGI1-antibody encephalitis diagnosed from January 2017 to February 2018 in First Affiliated Hospital of Zhengzhou University, and reviewed related literatures.
The 15/19 (79%) patients were male, and the average onset age was 58 years (23–82). The following cases were observed: 17 (89%) with epilepsy seizures, 14 (73%) with mental disorders, and 13 (68%) with cognitive impairment. Types of epilepsy were including focal aware seizures, focal-impaired awareness seizures, focal to bilateral tonic–clonic seizures, and status epilepticus. The motor events were most commonly clonus or automatisms, and the sensory events were frequently body shuddering. The 13 patients had faciobrachial dystonic seizures (FBDS); the median frequency was 48 per day (range 5–180). In some video-EEGs, multifocal ictal epileptiform discharges from frontal, temporal, and apical regions, and interictal slow wave activity were observed in patients. Normal EEG appeared in all patients during FBDS. Five patients had hyponatremia, and brain magnetic resonance imaging (MRI) results of 5 cases were abnormal. All patients were treated with antiepileptic drugs and immunotherapy, and their clinical symptoms were improved. During the follow-up period, 13 patients recovered basically, and 6 patients relapsed. One patient died of status epilepticus after relapse.
Faciobrachial dystonic seizure and various types of epileptic seizures are characteristic manifestations of LGI1-antibody encephalitis, which can assist in early diagnosis. Once this has been diagnosed, antiepileptic drugs and immunotherapy should be given as soon as possible to the patient.
•FBDS and various types of epileptic seizures are main symptoms of LGI1-antibody encephalitis.•Normal EEG appeared in all patients during FBDS.•An early diagnosis and immunotherapy suggested a better prognosis.
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