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Previous studies have reported the association between particulate matter (PM) and childhood allergic rhinitis (AR). However, it is unclear whether food allergy (FA) modifies the PM–AR association. We aimed at evaluating the effect of the modification of FA on PM–AR association in preschool children. We adopted a cross-sectional study and conducted a questionnaire survey among preschool children aged 3–6 years in 7 cities in China from June 2019 to June 2020 to collect information on AR and FA. We used a combination of multilevel logistic regression and restricted cubic spline functions to quantitatively assess whether FA modifies the associations between size-specific PM exposure (1 × 1 km) and the risk of AR. The adjusted odds ratios (ORs) for AR among the children with FA as per a 10 μg/m3increase in early life PM1, PM2.5, and PM10were significantly higher than the corresponding ORs among the children without FA [e.g., OR: 1.58, 95% CI: (1.32, 1.90) vs 1.29, 95% CI: (1.18, 1.41), per 10 μg/m3increase in PM1]. The interactions between FA and size-specific PM exposure and their effects on AR were statistically significant (all p-int < 0.001). FA, as an important part of the allergic disease progression, may modify the PM–AR association in preschool children.

This paper introduces a sequential black-start system restoration procedure in a system with 100% inverter based resources considering system inertia. First, the capability of virtual inertia supported by controlled grid-forming inverters at various locations in a 100% inverter based resources system is calculated through estimation of signal parameters via rotational invariance and nonlinear least square technique; second, a set of radiality constraints is designed for network topology to track inertia value at each bus to find the best restoration paths. Case studies on the modified 39 bus New England system demonstrate that the proposed approach outperforms the existing state-of-the-art approaches in tracking speed and accuracy.

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Volatile organic compounds (VOCs) are major gaseous pollutants and one of the main causes of environmental problem, which can be extremely harmful to human health. Previous research has shown that photocatalytic oxidation is regarded as a promising technology to remove VOCs. However, for the time being, the photocatalytic performance in the field of removing VOCs by multiple reported photocatalysts cannot meet the demand of the practice. In this study, we have successfully synthesized a series of 3D gel composites with g-C3N4(GC) and graphite oxide as precursors by a simple hydrothermal and freeze-drying method, which shows good photocatalytic degradation performance for gas toluene as model VOCs. The highest photocatalytic degradation ratio for gaseous toluene is about 86% in 180 min, which is about 3 times that of pure GC. The reason for the results is due to the strong adsorption capacity and very fast electrical conductivity of three dimensional (3D) reduced graphene oxide (RGO). This study implies that the 3D GC-RGO gels have potential usefulness for removing VOCs to meet the demand of the practice.

In order to solve the low efficiency and speed of information exchange in the traditional art of digital information exchange platform, the paper proposed and designed a new networking technology based on digital teaching college art information exchange platform.. In support of networking technology, the design needed a teaching information acquisition layer, transport layer, an access layer and a service layer, with the hierarchical construct art digital teaching exchange and sharing of information on the internet. With the support of the platform, ant colony algorithm is improved, and the ant colony algorithm classified information was used to improve art education, teaching information to complete the integration of fine arts. Experimental results show that in the designed exchange platform, the exchange of information was more efficient and has faster responses.

Cordyceps militarisis known for its production of cordycepin, which possesses various biological activities. Silkworm pupae serve as the hosts for Cordyceps militaris, thereby facilitating the synthesis of cordycepin. In this work, the components of silkworm pupae were isolated and used as regulatory factors to promote liquid fermentation of C. militaristo produce cordycepin. Compared with lipids, crude proteins in silkworm pupae are more capable of promoting cordycepin synthesis. Notably, when four proteins (albumin, globulin, gladin and gluten) isolated from crude proteins were added to the fermentation system according to their extraction rates, only globulin had a similar promotional effect as crude protein. In addition, supplementation with 3.31 g/L globulin extended the cordycepin synthesis stage for 6 days, during which the expression level of cns1-4, genes related to cordycepin synthesis, were significantly up-regulated. Transcriptome analysis of the metabolic pathway of C. militarisafter globulin supplementation revealed that the upregulation of glucose metabolism and energy metabolism played a crucial role in extending the synthesis stage of cordycepin to 2.5 times. Silkworm pupae globulin is the main functional factor regulating the synthesis of cordycepin in C. militaris, and is a potential material for industrial production of cordycepin.

Short-term load forecast (STLF) is important to ensure stable, reliable and efficient power system operations. In this paper, we propose a two-stage artificial neural network (ANN) model for load forecasting application. The proposed system is currently being tested in the Taiwan Power Company (TPC) with potential for future adoption in their decision support systems. The accuracy of the proposed forecast model is tested using the historical data obtained from TPC; the results show that the proposed two-stage ANN model can outperform a previously proposed single stage ANN load forecast model.

Islanded microgrids can experience severe frequency variation due to their inherently low inertia. Virtual inertia has been proposed in the literature to overcome this shortage. Virtual Synchronous Machine (VSM) concept has been the cornerstone of realizing virtual inertia from inverter connected energy sources. In this paper we propose and solve an optimal control problem to identify the optimal switching controls that achieve best dynamic frequency response from VSM. The results show that the optimal number of switching stages is independent of system parameters, and the optimal timing for switching between two control modes can be determined using local measurements alone, without having to perform complex computations.

Silkworm pupae oil (SPO) was regarded as a good alternative to alpha-linolenic acid supplements, which contain a variety of triacylglyceride with high nutritional value. To investigate the connections between triacylglyceride composition and lipid gastrointestinal digestive absorption profiles, isolation and bioavailability of triacylglyceride monomers from silkworm pupae oil was analyzed. In this study, two triacylglyceride monomers rich in α-linolenic acid were separated by preparative liquid chromatography, namely LnLnLn (1,2,3- α-linolenic acid triacylglyceride) and LnLnL (1,2- α-linolenic acid, 3- linoleic acid triacylglyceride). The in vitrodigestion in the pH-stat model results showed the digestive rate of LnLnLn was 0.4101 ± 0.0089 s−1, which was significantly higher than that of SPO (0.2494 ± 0.0108 s−1) (p < 0.05). The in vitroabsorption in the Caco-2 cells model results showed the absorptivity of LnLnLn and LnLnL were 6.40 ± 0.19% and 6.06 ± 0.54%, which were significantly higher than SPO (5.43 ± 0.51%) (p < 0.05). In addition, the mRNA expression levels of lipid metabolism-related proteins provide evidence for the absorption superiority of LnLnLn and LnLnL. The present work provides novel structural lipids for rapid and efficient supplementation of α-linolenic acid.

As the integrator of energy resources (DERs), a virtual power plant (VPP) would be able to control the amount of the power access to the distribution transformers such that energy efficiency can be improved. Battery energy storage system (BESS) and demand response (DR) as DERs can entrust the VPP with certain controllability to regulate the power supply of the distribution system. This paper aims to maximize the benefit of the supplied powers over the 24 hours under VPP operation. Combining an iterative dynamic programming optimal BESS schedule approach and a PSO-based DR scheme optimization approach, an optimal VPP operational method is proposed to minimize the total electricity cost with respect to the power supply limit of the distribution transformers and the system security constraints, especially, within the peak load hours. With the TOU rate given each hour, test results had confirmed the validity of the proposed method with the obviously decreased power supply in each peak-load hours and the largely reduced electricity cost accordingly.

Influence of Mn2+, Mg2+ and Ca2+ on β-D-glucosidase activity produced by Xanthophyllomyces dendrorhous was measured. The presence of Mn2+ could increase the β-D-glucosidase activity and the change in cell morphology of obviously improves the cell growth and the astaxanthin biosynthesis. The cell biomass, the astaxanthin yield and the astaxanthin content in dry cell was reached to 3.65 g L-1, 3.06 mg L-1 and 0.84 mg g-1 at 72 h of fermentation respectively, which were higher than those in absence of Mn2+.

AbstractWith the rapid development of urbanization, the economy and number of vehicles, the urban climate has worsened in recent years, causing serious urban problems including urban heat islands, air pollution and infectious disease transmission. Ventilation is indicated as one of the most effective approaches to solve these problems. Based on the traditional concept of room ventilation, the present work developed a new physical model and lumped mathematical model for urban ventilation, which is the product of both horizontal wind speed and vertical mixing layer height. This urban ventilation model was validated by a case study implemented in the city of Changsha. Both Pearson correlation analysis and principal component analysis (PCA) indicated that the urban heat island intensity and PM10concentration are significantly negatively correlated with the urban ventilation rate, i.e. urban mixing layer height and wind speed.

An essential problem in a deregulated power system is the long-term availability of peaking capacity. One potential solution, which has received increasing attention, is the demand reduction/exchange program in power markets. A voluntary real-time demand reduction program provides an opportunity for customers to reduce their demands during times of high prices and share the benefits of the program. An Independent System Operator (ISO) can use a fixed price to buy demand reductions from customers; the benefits obtainable, due to the relief of line congestion constraints and market power, can be shared both by the ISO and program participants. If the optimal curtailment price bid can be determined then social welfare can be maximized. For these purposes, the basic task is to determine a rate structure, which gives incentives to both the ISO and the customers. The structure should minimize the cost of generation and maximize the economic benefit to the customers. In this paper, two solution formulations, including various levels of network constraints, are proposed to obtain the optimal curtailment bid and the economic impacts of the programs. Test examples are used to demonstrate the potential benefits obtainable for the ISO and participants from the voluntary demand-reduction programs.

In a competitive environment, load forecast serves two different applications. First, load forecast results can be used by retailers of power to study their opportunities and plan their business strategies. Second, accurate projections of load are useful for T&D operators in performing system operation and expansion studies. Several key elements in their market and system planning studies have strong location factors that the spatial load forecast can address. In this paper, a package that integrates a Geographic Information System (GIS) used for automatic mapping and facility management (AM/FM) and a spatial load forecast module is presented. The interface functions and the procedure of the fuzzy logic based spatial load forecast module are described. Simulation studies are performed on a metropolitan area of Kaohsiung, Taiwan.

In order to enhance the performance of trouble management in distribution system operations, information integration of SCADA and outage management systems was investigated. Using discrete event simulation techniques, three possible integration schemes were studied. This paper shows a thorough analysis of the system performance of integrated systems under realistic conditions. Test results have indicated that the integrated system, consisting of the two separate but related systems with connection through FDDI LAN, can maintain the performance requirement of each system, and at the same time enhance the overall performance of trouble management.

A vector implementation of sensitivity computation that can be used in the remedial action planning of N-1 steady state security assessment function is presented in this paper. In order to exploit the power of vector processors, the formulations of sensitivity calculation are restructured to minimize the execution time and the effects of data storage scheme are investigated. Tests of the proposed schemes are conducted on Alliant FX/80 and Convex 3840 machines. Test results have shown that the execution time required for obtaining a large set of sensitivity factors can be greatly reduced by using the proposed schemes on vector computers.

Distribution networks contain a large number of components and, in many cases, the required data for network modeling are often missing or uncertain. In order to circumvent the problem of dealing with uncertain data, uncertainties in network parameters and feeder node injections are handled by using the “unknown but bounded” scheme. A possibility approach used to take into account the effects of uncertainties in distribution system state estimation is proposed in this paper. In the proposed estimation approach, all possible solutions within bounds are considered. Test results have shown that this approach can handle various uncertainties that exist in the network model and the solutions obtained can provide useful information for distribution system operations.

The quality of feeder load distribution estimations will affect the switching schedules and the effectiveness of shunt compensation in distribution system operations. Accurate load distribution estimations are required in order to achieve the best schedule for maximizing the loss reduction. In this paper, a new feeder load distribution estimation method that removes the assumption of coincident peak load made in previous methods is proposed. Considering the non-conforming load effect, the new method uses data from load surveys and the customer information system to enhance the quality of the estimations. A dynamic programming algorithm is used to investigate the effects of time varying load distribution estimations on the switched capacitor schedules. Test results using actual measurement data have indicated that the proposed method could provide better estimations than the previous methods.

To observe the effect on RAS gene expression of different fine particle (PM2.5) components on human umbilical vein endothelial cells and to explore the potential mechanism.

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