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Changes in population density have profound impacts on mating behaviors in group-living animals. The plasticity of mating behavior enables insects to respond to social signals and adjust mating frequency in accordance with rival competition and reproductive opportunity.In this study, we found that low levels of cis-vaccenyl acetate (cVA), a Drosophila pheromone, increased mating rates of Bactrocera dorsalis, but high concentrations of cVA inhibited mating, indicating a functional role of cVA in regulating mating behaviors in insect species other than Drosophila. Moreover, we demonstrated that group housing conditions had positive effects for B. dorsalis on their mating rates, responses toward cVA and cVA-mediated mating behaviors, which are dependent on the activity of c-AMP reponse element binding protein (CREB) binding protein (CBP).Our data suggest that CBP-mediated plasticity in mating behavior and chemical recognition enables insects to adapt to different housing conditions and highlight the potential of cVA as an efficient agent in regulating mating behaviors in insect species other than Drosophila. © 2022 Society of Chemical Industry.

Leaf photosynthesis is largely determined by anatomical features. This study aimed to reveal the quantitative effects of the anatomical structure of Coffea arabica leaves on photosynthesis. Pearson’s correlation and path analysis were used to explore the correlation between leaf structure and photosynthesis. To calculate the comprehensive evaluation value of the correlation between leaf anatomical traits and photosynthetic parameters, the Criteria Importance Through Intercriteria Correlation (CRITIC) method was used to obtain the objective weight of each photosynthetic parameter. Most of the anatomical traits of the leaf significantly (P

Distributed energy systems are becoming increasingly popular worldwide. The 100% renewable energy system can be an important energy supply alternative to reduce the carbon emissions and address energy shortage, especially for remote areas. However, the performance of 100% renewable energy system (RES) at community level needs further detailed analysis, which is affected by the climates, availability of renewable energy and local energy markets. This paper proposes a design optimization framework of 100% renewable energy systems for low-density communities and investigates the system performance. To investigate the integration and performance of 100% RES, thirty typical cities located in different regions of China were chosen considering different climates, geographical features, and renewable energy distributions. By taking the economic performance as the optimization objective, the optimal design for the 100% RES is obtained, and the energy and economic performance is analyzed. Results show that, under the current energy market conditions, the 100% RES is feasible for low-density communities in most regions of China. The payback periods of the systems in most cities are less than six years. When the cost of PV is reduced by half considering future technological developments, the payback period of a 100% RES can be reduced by 30%–60%. This paper would provide design suggestions and application recommendations in regard to promoting 100% RES in China.

Materials are always among the first considerations to the development of low temperature solid oxide fuel cells (SOFCs). In this study, we investigate the multifunctionality of a layer-perovskite oxide La2-xCexCuO4 (LCCO) for its applications in SOFC as cathode, anode and electrolyte. The performances of the LCCO cathode and anode fuel cells are characterized by I–V–P and electrochemical impedance spectra (EIS). Results suggest that LCCO is a good cathode material and it can also deliver impressive anode performance. Though LCCO is noticed to be reduced by H2 in the anode, the cell performance is relatively stable under multiple times of operation. The existing of ceria and reduced Cu in it may be a reason for its anode catalytic activation. For the application in electrolyte, LCCO is mixed with ionic conductor Ce0.8Sm0.2O2-δ (SDC) in different weight ratios. Differences in power output and open circuit voltage for the cells containing various ratios of LCCO under normal and reverse operation conditions are highlighted. The electronic conductivity of LCCO doesn't bring in electronic leakage if it is kept in a certain range. The multifunctionality of LCCO would enable it to be potentially applied in single layer fuel cell to simplify the structure and fabrication process of SOFC.

Electrolyte densification, which is often realized by high temperature sintering (i.e. >1000 °C), is an essential process for solid oxide fuel cell (SOFC). However, it is hard to achieve interfaces with high ionic conductivity because the interfaces between particles would be greatly eliminated during the sintering process. In this study, a novel interface engineering method is designed basing on capillary action to densify the electrolyte and at the meantime achieve ionic conductive interfaces at low temperature. A porous electrolyte layer is found to become dense during fuel cell operation when alkali metal hydroxide (AMH) is added to the NiO anode. The observation of improved open circuit voltage (OCV) indicates gas leakage has been eliminated after AMH modification. Raman images confirm that AMHs can be absorbed into the electrolyte layer when the operating temperature is higher than the melting point of AMH. In addition, using a lithiated metal oxide (i.e. LiNiO2) as the anode, cell performance is further improved. EIS proves that the existing of AMH in the cell may affect gas diffusion in the electrode, but it significantly reduces ohmic resistance due to better interfacial ionic conductivity of the electrolyte. This in-situ electrolyte densification method not only enables us to simplify fuel cell fabrication process and lower the fabrication temperature but also provides ways for maintaining interface conductivity.

Load monitoring can help users learn end-use energy consumption so that specific energy-saving actions can be taken to reduce the energy consumption of buildings. Nonintrusive monitoring (NIM) is preferred because of its low cost and nondisturbance of occupied space. In this study, a NIM method based on random forest was proposed to determine the energy consumption of building subsystems from the building-level energy consumption: the heating, ventilation and air conditioning system, lighting system, plug-in system, and elevator system. Three feature selection methods were used and compared to achieve accurate NIM based on weather parameters, wavelet analysis, and principal component analysis. The implementation of the proposed method in an office building showed that it can obtain the subloads accurately, with root-mean-square errors of less than 46.4 kW and mean relative errors of less than 12.7%. The method based on weather parameters can provide the most accurate results. The proposed method can help improve the energy efficiency of building service systems during the operation or renovation stage.

Toluene and its derivatives are petroleum-derived raw materials produced from gasoline by catalytic reformation. These abundant chemical feedstocks are commonly used as solvents in organic synthesis. The C(sp3)−H functionalization of these unactivated substrates has been widely used to directly introduce benzylic motifs into diverse molecules to furnish important compounds. Despite these advances, progress in asymmetric catalysis remains underdeveloped. Here, we report photoinduced radical-based enantioselective C(sp3)−C(sp3) coupling reactions of activated ketones with toluene and its derivatives by means of chiral acid catalysis. With a La(OTf)3/pybox complex catalyst, a variety of chiral 3-hydroxy-3-benzyl-substituted 2-oxindoles, including many conventionally difficult-to-access variants, are obtained directly from isatins in high yields with good to excellent enantioselectivities. Acenaphthoquinone is also compatible with the use of a chiral phosphoric acid (CPA) catalyst, leading to another series of important enantioenriched tertiary alcohols., Asymmetric transformations involving abundant chemical feedstocks such as toluene and its derivatives are rather rare. Here, the authors report the radical enantioselective C(sp3) −C(sp3) coupling of activated ketones with toluenes by means of chiral acid catalysis to afford enantioenriched tertiary alcohols.

The promising 2D materials for sodium ion battery always suffer from dramatically sluggish electronic and ionic transport due to the irreversible agglomeration phenomenon. In order to tackle this problem, ethylene glycol is adopted in this work as a soft template in directing the growth of 2D structure based on the chelating ability and hydrogen-bonding chains. Subsequently, ethylene glycol could be in-situ transformed into carbon super electronic networks after the thermal treatment, to dramatically enhance the electrical conductivity and prevent the agglomeration of 2D sheets. Since the highly dispersed nanoflake structures and super electronic network could offer nano-sized effects and ultrashort ion-transport paths, the agglomeration-resistant Na3V2(PO4)3 (NVP) nanoflake displays exciting rate capabilities (about 71.2 mAh g−1 at 200 C, and 56.2 mAh g−1 at the ultrahigh rate of 300 C) and ultralong lifecycles. Our results suggest the potential application of 2D nano-structured NVP cathodes for transportation and large-scale grid storage.

The ionic conductivity and small size of the hydrogen ion make it an ideal charge carrier for hydrogen-ion energy storage (HES); however, high-voltage two-electrode configurations are difficult to construct as the result of the lack of efficient cathodic energy storage. Herein, the high potential fast anionic redox at the cathode of reduced graphene oxide (rGO) was applied by introducing redox additive electrolytes. By coupling the storing hydrogen ion in the Ti3 C2 Tx at the anode, a HES with a voltage of 1.8 V and a plateau voltage at 1.2 V was constructed. Compared with 2.2 Wh kg-1 for the low-voltage Ti3 C2 Tx //Ti3 C2 Tx , the specific energy of asymmetric rGO//Ti3 C2 Tx reaches 34.4 Wh kg-1 . Furthermore, it possesses an energy density of 23.7 Wh kg-1 at high power density of 22.5 kW kg-1 . Thus, this study provides a novel guideline for constructing high-voltage fast HES full cells.

This study presents a stability analysis of an extended berm reinforced by geotextiles, with a steep slope of 1V:1.1H (vertical: horizontal). Finite element (FE) analyses were carried out to explore the failure mechanism and factor of safety (FOS) of the berm, on which the effect of the strength of geotextiles, leachate level, and anti-slide pile arrangement located at the toe of the berm were considered. It was found that: (1) failure surfaces developed along the interface between the new and the existing berms, (2) the FOS decreased as the leachate increased, and an FOS value of 1.42 could be obtained if the leachate level was controlled at a height of 20 m, (3) the tensile force of geotextiles was far lower than the available strength, which suggested that the geotextile had enough of a safety reserve, and (4) one row of longer piles at the toe of the berm performed better than two rows of shorter piles if the total length of piles was the same. The design and analysis of this project can be used as a reference for landfill expansion. Especially for a site condition with limited space, a geosynthetic-reinforced soil (GRS) berm is a safe, reliable and promising alternative.

A better understanding of the runoff variations contributes to a better utilization of water resources and water conservancy planning. In this paper, we analyzed the runoff changes in the Yangtze River Basin (YRB) including the spatiotemporal characteristics of intra-annual variation, the trend, the mutation point, and the period of annual runoff using various statistical methods. We also investigated how changes in the precipitation and temperature could impact on runoff. We found that the intra-annual runoff shows a decreasing trend from 1954 to 2008 and from upper stream to lower stream. On the annual runoff sequence, the upstream runoff has a high consistency and shows an increasing diversity from upper stream to lower stream. The mutation points of the annual runoff in the YRB are years 1961 and 2004. Annual runoff presents multitime scales for dry and abundance changes. Hurst values show that the runoffs at the main control stations all have Hurst phenomenon (the persistence of annual runoff). The sensitivity analyses of runoff variation to precipitation and temperature were also conducted. Our results show that the response of runoff to precipitation is more sensitive than that to temperature. The response of runoff to temperature is only one-third of the response to precipitation. A decrease in temperature may offset the impact of decreasing rainfall on runoff, while an increase in both rainfall and temperature leads to strongest runoff variations in the YRB.

Heating, ventilation and air conditioning (HVAC) system plays a significant role in demand response (DR) to reduce the peak load of the grid. Conventionally, only the sensible load is reduced by increasing the indoor temperature during DR periods and the latent load is rarely concerned. This study proposes a temperature & humidity (T&H) setback strategy for HVAC systems to reduce both the sensible and latent cooling loads by adjusting the supply air temperature and chilled water supply temperature simultaneously. The performance of the T&H setback strategy is analyzed from the perspectives of peak shedding, energy saving and indoor thermal comfort and compared with the common temperature setback strategy. The impact of weather conditions and occupant densities on the performance of T&H strategy is assessed. Results show that the energy saving of the HVAC system under the T&H setback strategy can be up to 39.0% and peak shedding can be increased to 37.1%, which are both higher compared with the temperature setback strategy. The peak shedding and energy saving of the T&H setback strategy is larger when the buildings have lower sensible or higher latent load. The T&H strategy can improve the flexibility of buildings during DR periods effectively.

Detailed monitoring of loads can provide sufficient information about buildings and help in improving the operation of energy systems. Non-intrusive load monitoring (NILM) has become popular owing to its low cost and lack of disturbance in the occupied space. In this study, NILM methods based on artificial neural network (ANN) and random forest (RF) are proposed and compared to obtain the sub-loads of cooling loads. The cooling loads are disaggregated into four sub-loads: occupant load, equipment load, fresh air load, and building envelope load. Results showed both NILM methods could achieve load disaggregation accurately, but the RF-based NILM method performs better than that based on ANN. Moreover, the RF-based NILM method has mean relative errors (MREs) between 2.5% and 13.0%, while the ANN-based NILM method has MREs between 3.1% and 12.9%. Among the four sub-loads, the equipment load could be disaggregated with the highest accuracy. The detailed sub-loads obtained using the proposed NILM methods can guide building renovation and optimization design of building energy systems.

Accurate load monitoring can provide detailed information for users to improve the energy efficiency of buildings. Non-intrusive load monitoring (NILM) has become popular in smart buildings because of its low cost and reasonable privacy. In this paper, a non-intrusive monitoring method for the cooling load of smart buildings is proposed based on random forest. The total building cooling load is disaggregated into four subloads, and two approaches are used to realize the NILM based on the direct or indirect cooling load using a Fourier transform. The proposed method is implemented in an office building, and results show the method can realize cooling load disaggregation accurately. The root-mean-square errors and mean relative errors of the four subloads between the NILM loads and reference loads are less than 51.9 kW and 19.1%. Among the four subloads, the equipment load can be disaggregated with the highest accuracy. Approach I is recommended because of its higher accuracy. The NILM method is optimized in terms of the estimator number, maximum depth, feature number, minimum samples for a split, minimum sample leaf, and size of training samples. The performance of the optimized NILM models is improved with RMSEs and MREs less than 48.3 kW and 6.4%.

Geographic models are becoming key methods for geographic environment research. In addition to the progress in model sharing and reusing, geographic simulation (geo-simulation) knowledge sharing and application are increasingly attracting much attention. This study aims to provide both models and geo-simulation knowledge simultaneously to support Web-based simulation. Firstly, we propose a geo-simulation approach consisting of three modules concerning data, model and knowledge with a conceptual framework. Secondly, taking the Storm Water Management Model as instance, a Web-based prototype system is implemented with geo-simulation knowledge graph constructed based on literatures using bilateral long shortterm memory - conditional random field (BiLSTM - CRF). Thirdly, application of the system in Nanchong, China is conducted with user experiences analysis. The results demonstrate that the proposed approach can effectively provide geo-simulation knowledge. Moreover, it can alleviate the difficulty of the geographic simulation process for diverse modelers, and further improve the use of the model simultaneously.

College buildings, especially college dormitories, have a high density of energy consumption. It is important to obtain the energy consumption characteristics and impact factors of college dormitories before implementing energy efficiency measures. However, few studies based on experimental data have been reported. This study attempts to analyze the energy consumption characteristics of college dormitories and determine the influential factors based on monitored data. Annual daily energy consumption data of 480 college dormitories with different orientations and floors were collected. The energy consumption characteristics and the impact of factors including the floor, orientation, and occupant’s gender are investigated and quantified through the statistical methods and covariance analysis. The results show that the energy consumption varies significantly between different dormitories, and the floor location is the most influential factor. The annual energy consumption of the dormitories on the top floor is 1015% higher compared with those on the other floors due to higher cooling or heating load resulting from the roof. Then, two floor-oriented electricity pricing strategies are recommended to balance the different energy bills caused by different located floors of rooms. The electricity tariffs for rooms on the middle/top floors should be increased/decreased by 3.5%/10.3% in the proposed floor-based electricity tariff. This study would provide a basis for energy efficiency improvement and tariff optimization for college dormitories.

The NAC gene family is one of the largest families of transcriptional regulators in plants, and it plays important roles in the regulation of growth and development as well as in stress responses. Genome-wide analyses have been performed in diverse plant species, but there is still no systematic analysis of the NAC genes of Coffea canephora Pierre ex A. Froehner. In this study, we identified 63 NAC genes from the genome of C. canephora. The basic features and comparison analysis indicated that the NAC gene members increased via duplication events during the evolution of the plant. Phylogenetic analysis divided the NAC proteins from C. canephora, Arabidopsis and rice into 16 subgroups. Analysis of the expression patterns of CocNACs under cold stress and coffee bean development indicated that 38 CocNACs were differentially expressed under cold stress, six genes may play important roles in the process of cold acclimation, and four genes among 54 CocNACs showing a variety of expression patterns during different developmental stages of coffee beans may be positively related to the bean development. This study can expand our understanding of the functions of the CocNAC gene family in cold responses and bean development, thereby potentially intensifying the molecular breeding programs of Coffea spp. plants.

Peptides presented by Human leukocyte antigen (HLA) class-I molecules are generally 8–10 amino acids in length. However, the predominant pool of peptide fragments generated by proteasomes is less than 8 amino acids in length. Using the Epstein - Barr virus (EBV) Rta-epitope (ATIGTAMYK, residues 134–142) restricted by HLA-A*11:01 which generates a strong immunodominant response, we investigated the minimum length of a viral peptide that can constitute a viral epitope recognition by CD8 T cells. The results showed that Peripheral blood mononuclear cells (PBMCs) from healthy donors can be stimulated by a viral peptide fragment as short as 4-mer (AMYK), together with a 5-mer (ATIGT) to recapitulate the full length EBV Rta epitope. This was confirmed by generating crystals of the tetra-complex (2 peptides, HLA and β2-microglobulin). The solved crystal structure of HLA-A*11:01 in complex with these two short peptides revealed that they can bind in the same orientation similar to parental peptide (9-mer) and the free ends of two short peptides acquires a bulged conformation that is directed towards the T cell receptor. Our data shows that suboptimal length of 4-mer and 5-mer peptides can complement each other to form a stable peptide-MHC (pMHC) complex.

The demand of building energy management has increased due to high energy saving potentials. Load monitor and disaggregation can provide useful information for building energy management systems with detailed and individual loads of the building, so corresponding energy efficient measures can be taken to reduce the energy consumption of buildings. The technique is investigated widely in residential buildings known as Non-Intrusive Load Monitoring (NILM). However, relevant studies are not sufficient for non-residential buildings, especially for the cooling loads. This paper proposes a NILM method for cooling load disaggregation using artificial neural network. The cooling load is disaggregated into four categories: building envelope load, occupant load, equipment load and fresh air load. Two approaches are used to realize the load disaggregation: one is based on the Fourier transfer of the cooling loads, the other takes the cooling load, dry-bulb temperature and humidity of outdoor air, and time as inputs. By implementing the methods in a metro station, the performance of the proposed method can be obtained. Results show that both approaches can realize the load disaggregation accurately, with a RMSE less than 11.2. The second approach is recommended with a higher accuracy.