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To achieve reactive voltage control and resolve the problem of photovoltaic in regional grids with high-proportion photovoltaic access, a multi-cycle reactive voltage rolling optimization control method supporting photovoltaic absorption was proposed, and a multi-cycle reactive voltage rolling optimization control framework was constructed based on the sensitivity-based mathematical model of allowed maximum photovoltaic capacity. First, a reactive power optimization model was built day ahead to minimize the actions of the discrete reactive regulating equipment and the resistance of photovoltaic absorption, and the action plan for discrete reactive power regulating equipment was thus determined. After that, with the determined day-ahead control plan for discrete reactive equipment as the constraint, and with the maximization of photovoltaic absorption and improvement of the dynamic reactive reserve margin of the system as the objectives within day, a reactive voltage rolling optimization control model was built for the optimal control plan for the discrete and continuous reactive equipment; the rolling optimization control model performed optimization once every five minutes, with two hours as a cycle. At last, with a regional grid system as a study case, a simulating calculation was carried out and the control effects after optimization by the proposed multi-cycle reactive voltage rolling optimization control method showed that the maximum voltage deviation of two key nodes had been dropped by 34.21% and 45.98%, respectively, the action times of capacitors and the regulation times of main transformers had been reduced by 61.29% and 64%, respectively, the maximum regulation capacity requirement of continuous reactive equipment in photovoltaic stations had been dropped by 62.17%, and the forecast photovoltaic output could be fully absorbed in this system. These findings verified the feasibility and effectiveness of the proposed method in improving voltage control and promoting maximum photovoltaic absorption of regional grid. The case study showed that the day-ahead optimization control method could alleviate the large fluctuations of photovoltaics by arranging a discrete reactive power equipment adjustment plan, and the within-day rolling optimization control could adjust the output of continuous reactive power equipment to alleviate short-term random fluctuations of photovoltaics after simulating calculation.

Submarine or sub-lacustrine lobe deposits are important reservoirs, but the fan fringe deposits form heterogeneities within deep water fan deposits. Fan fringe facies records the complex sediment gravity flow types. By understanding of the bed types and flow mechanisms, we can identify the fan fringe deposit, which aids in the reconstruction of deep water fan and reservoir evaluations. The Jiucaiyuanzi and Dalongkou sections in the West Bogda Mountains preserve well-exposed 536-m and 171-m thick successions, respectively, of a deep water lacustrine depositional system from the Middle Permian Lucaogou Formation. Bed types of the Lucaogou Formation include high-density turbidite, low-density turbidite, incomplete Bouma-type turbidite, hybrid event beds, and slump deposits. The Lucaogou Formation is interpreted here as a fan fringe facies due to the thin bed thickness that characterize turbidites and hybrid event beds, as well as the predominance of the isolated sheet architecture. Previous studies suggest that these deposits were considered as deposited in a deep water setting due to the absence of wave-related structures. The presence of abundant mud clasts in massive medium-coarse grained sandstone beds reflects the significant erosional capability and interactions between high-density turbidity currents and lake floor. The fan fringe facies here contains amalgamated and thick-bedded homolithic facies (~ 30%) and thin-bedded heterolithic facies (~ 70%). The examination of the bed type is of wider significance for facies prediction and reservoir heterogeneity in the sub-lacustrine fan fringe facies.

Antimicrobial resistance (AMR) is one of the significant global issues to public health. Compared to other aquatic environments, research on AMR in groundwater is scarce. In the study, a meta-analysis was conducted to explore the characteristics and risks of antibiotics and antibiotic resistance genes (ARGs) in global groundwater, using a data set of antibiotic concentrations collected from publications during 2000-2021 and a large-scale metagenomes of groundwater samples (n = 330). The ecotoxicological risks of antibiotics in the global groundwater were evaluated using mixture risk quotient with concentration addition model to consider the synergistic effects of multiple antibiotics. Bioinformatic annotations identified 1413 ARGs belonging to 37 ARG types in the global groundwater, dominated by rifamycin, polyketide, and quinolone resistance genes and including some emerging ARGs such as mcr-family and carbapenem genes. Relatively, the level of ARGs in the groundwater from spring was significantly higher (ANOVA, p0.01) than those from the riparian zone, sand and deep aquifer. Similarly, metal resistance genes (MRGs) were prevalent in the global groundwater, and network analysis suggested the MRGs presented non-random co-occurrence with the ARGs in such environments. Taxonomic annotations showed Proteobacteria, Actinobacteria, Eukaryota, Acidobacteria and Thaumarchaeota were the dominant phylum in the groundwater, and the microbial community largely shaped profile of ARGs in the environment. Notably, the ARGs presented co-occurrence with mobile genetic elements, virulence factors and human bacterial pathogens, indicating potential dissemination risk of ARGs in the groundwater. Furthermore, an omics-based approach was used for health risk assessment of antibiotic resistome and screened out 152 risk ARGs in the global groundwater. Comparatively, spring and cold creek presented higher risk index, which deserves more attention to ensure the safety of water supply.

Carbohydrates play important roles in life science, but their synthesis is always hampered by their complicated chemical structures. Scientists have never stopped trying to solve the problem of glycan synthesis from various aspects. Here a brief overview of recent progress in glycan synthesis, including chemical approaches, chemoenzymatic approaches, and automated synthesis, will be discussed, focusing on the efficiency of new glycosylation methods, the stereoselectivity of coupled products, and their applications in the assembly of complex glycan chains.

Although macrophage migration inhibitory factor (MIF) is known to have antioxidant property, the role of MIF in cardiac fibrosis has not been well understood. We found that MIF was markedly increased in angiotension II (Ang-II)-infused mouse myocardium. Myocardial function was impaired and cardiac fibrosis was aggravated in Mif-knockout (Mif-KO) mice. Functionally, overexpression of MIF and MIF protein could inhibit the expression of fibrosis-associated collagen (Col) 1a1, COL3A1 and α-SMA, and Smad3 activation in mouse cardiac fibroblasts (CFs). Consistently, MIF deficiency could exacerbate the expression of COL1A1, COL3A1 and α-SMA, and Smad3 activation in Ang-II-treated CFs. Interestingly, microRNA-29b-3p (miR-29b-3p) and microRNA-29c-3p (miR-29c-3p) were down-regulated in the myocardium of Ang-II-infused Mif-KO mice but upregulated in CFs with MIF overexpression or by treatment with MIF protein. MiR-29b-3p and miR-29c-3p could suppress the expression of COL1A1, COL3A1 and α-SMA in CFs through targeting the pro-fibrosis genes of transforming growth factor beta-2 (Tgfb2) and matrix metallopeptidase 2 (Mmp2). We further demonstrated that Mif inhibited reactive oxygen species (ROS) generation and Smad3 activation, and rescued the decrease of miR-29b-3p and miR-29c-3p in Ang-II-treated CFs. Smad3 inhibitors, SIS3 and Naringenin, and Smad3 siRNA could reverse the decrease of miR-29b-3p and miR-29c-3p in Ang-II-treated CFs. Taken together, our data demonstrated that the Smad3-miR-29b/miR-29c axis mediates the inhibitory effect of macrophage migration inhibitory factor on cardiac fibrosis.

The microbial spoilage of soybeans during soaking process severely deteriorates the quality of soybean products and threatens human health. Herein, water-soluble aminated zinc oxide nanoparticles (ZnO NPs) were developed to effectively control the microbial spoilage in soybeans during soaking. ZnO NPs achieved significant inactivation of three dominant spoilage bacteria (bacillus cereus, bacillus megaterium and enterococcus faecium) isolated from the deteriorated soybeans, which could adhere to the bacterial surface and damage the cell wall/membrane, but also generate large amounts of reactive oxygen species (ROS). Compared to two commercial ZnO, water-soluble ZnO exhibited superior antibacterial properties due to producing more ROS and bacteria-adhered ability. After ZnO NPs treatment, the content of the residual Zn (51.1 mg/kg) in soybeans was the safety standards of Zn element in soybeans products for human). Therefore, the water-soluble ZnO NPs showed great potentials as efficient and safe antimicrobial agents for soybeans preservation during soaking process.

In this study, neural-signal electroencephalogram (EEG) methods to improve human-building interaction under different indoor air quality conditions were investigated. Experiment was conducted to study correlations between EEG frequency bands and subjective perception as well as task performance. Machine learning-based EEG pattern recognition methods as feedback mechanisms were also investigated. Results showed that EEG theta band (4–8 Hz) correlated with subjective perceptions, and EEG alpha band (8–13 Hz) correlated with task performance. These EEG indices could be utilized as more objective metrics in addition to questionnaire and task-based metrics. For the machine learning-based EEG pattern recognition methods, the linear discriminant analysis (LDA) and support vector machine (SVM) classifiers can classify mental states under different indoor air quality conditions with high accuracy. In general, the EEG theta and alpha bands as more objective indices and the machine learning-based EEG pattern recognition methods as real-time feedback mechanisms have good potential to improve the human-building interaction.

In laser satellite communications, studies of the scintillation index that are based on the three-layer altitude-dependent turbulence model have paid little attention to the different character of stratospheric turbulence from turbulence in the other two layers. This difference is a consequence of the special power spectrum with a power law exponent of 5. By adopting different wave structure functions at different altitudes in the extended Rytov theory, we analyze the scintillation index along the slant path in the regime of moderate-to-strong turbulence. Our results show that the weak fluctuation theory is limited to a smaller zenith angle, and the scintillation index has a larger maximum value in the focusing regime, when compared to the Kolmogorov model. We also find that the change of the scintillation index with the outer scale of the stratospheric turbulence only appears with moderate-to-strong turbulence, and it weakens with the increase of the turbulence outer scale. Moreover, the impact of the Gaussian beam radius on the scintillation index is different in the downlink and the uplink paths. We can approximate the downlink beam as a plane wave in most cases, but we must optimize the uplink beam to minimize the irradiance fluctuation.

An efficient and novel methodology to access phenolic glycosides has been established by using copper-mediated coupling reaction of aryl boronic acids with hemiacetals. The reaction takes place normally in the presence of Cu(OAc)2 (1.0 equiv.) and pyridine (2.0 equiv.) at 40 °C. This protocol distinguishes itself by wide substrate scope, operational simplicity and giving rise to a myriad of phenolic glycosides in good to excellent yields.

The fabrication of wafer-scale multilayers molybdenum disulfide (MoS2) induced by sulfurizing molybdenum (Mo) seed layer could compatible with traditional semiconductor process but the random growth orientations especially the vertical aligned structures lead to the unreliability for electronic devices thus hindered their wide application. Here, we utilize multi-step heating (MH) sulfurization method to regulate the sulfurization rate and diffusion rate of thermal sulfur vapor, thus realize the fabrication of MoS2 nanofilms with wafer-level uniformity and based on this, we integrate back-gate field-effect transistor (FET) arrays with an average hole mobility of 0.9cm2 V−1 s−1 and high device yield (~98%) which illustrate the reliable electrical-performance among the device arrays and the high quality of the as-fabricated MoS2 nanofilms. Therefore, we believe our efforts could pave the way for fabricating wafer-scale transition metal dichalcogenides (TMDCs) nanofilms with high uniformity and promoting their application for the integration of electronics/optoelectronics.

Effects of indoor environmental quality of office buildings on occupants have been widely studied. However, relatively fewer studies focus on that of educational buildings, through the perspective of building life cycle costing assessment in particular. In this study, effects of indoor thermal condition and air quality on students' wellbeing and performance are investigated with other major building metrics through a life cycle costing case study of two university tutorial rooms. Metrics for students' wellbeing and performance are monetized, and different weighting schemes for the metrics are compared with sensitivity analysis. Results show that consideration of students' wellbeing and performance can lead to significant total net benefits, which highlights that other traditional metrics focusing on building energy and resource efficiency should be balanced with human factors. For more sustainable building design and operation, balanced weighting scheme should be adopted, in contrary to the current practice where weights are mainly given to capital and energy while wellbeing and performance are often ignored. The results underscore the importance of incorporating students' wellbeing and performance into educational building design and operation, as thermal or air quality conditions in school classrooms are often worse than stipulations in standards and building codes. NRF (Natl Research Foundation, S’pore) Accepted version

This study investigated the late Quaternary sedimentary evolution of the outer shelf of the East China Sea (ECS) using borehole core data (DH02). Three unconformity-bounded sedimentary facies, namely, prodelta facies of marine isotopic stage (MIS) 3, intertidal to subtidal flat facies of the deglacial period, and offshore tidal sand ridge facies of the Holocene, were identified from the base upward according to combined evidence of lithology, microfossil assemblages, and geochronology. Through comparative analysis with other neighboring borehole cores, these three facies, along with the MIS 3 nearshore facies and the last glacial maximum (LGM) river facies, were found to constitute the late Quaternary sediment strata. Sedimentary processes of these five facies were interpreted based on a synthetic consideration of sea-level change, climate variation, paleotopographic setting, and paleoriver-sea interactions. In particular, the development of the delta was attributable to integration of the slow sea-level decline during the later stage of the MIS 3 and abundant sediment supply resulting from the warm-wet climate. The gentle shelf topography suggests the presence of shallow and wide rivers in the delta, and the lateral shift of river channels might have induced the local formation of nearshore facies at the abandoned river mouth. The LGM river facies, which was rarely observed (presumably due to marine erosion with deglacial transgression), was inferred to have been deposited during the latter half of the LGM in response to the rise in river base level. Occurrences of tidal flat facies imply the formation of a tide-dominated estuary with the deglacial transgression. Furthermore, tidal flat sediments were reworked by enhanced tidal currents in the estuary front environment, forming mud ridges during subsequent deglacial transgression. Formation of tidal sand ridges in offshore environments of the Holocene was attributable to the uneven base caused by the underlying estuarine erosion mud ridges, and this promoted the occurrence of tidal depositional processes. The sedimentary evolution in association with sea-level change was constructed using the above-mentioned results. Overall, this study systematically elucidates the late Quaternary sedimentary processes and evolution of the outer ECS shelf, and provides an insight into the sedimentary development of analogous shelves around the world.

A metal-free and light-promoted approach to the synthesis of N -9 alkylated purine nucleoside derivatives, via a CF 3 radical triggered radical relay pathway, has been developed. Purine nucleoside derivatives were prepared regioselectively in good to high yields. Photosensitizers and metals are free in this transformation. Visible light or even sunlight can be used as the source of light for the reactions.

Singapore is a city-state with limited land space and resources, and most construction materials are imported from foreign countries. In this study, a detailed whole building life cycle assessment (LCA) of a base case building in Singapore as well as material LCA were conducted with customized life cycle inventory datasets by considering materials importation and transportation in particular, and by considering the effects of adopting local recycled aggregates. Results showed that importation and transportation of construction materials significantly alter environmental impacts. This highlights the necessity of considering transportation for importing materials in Singapore context. Inclusion of local recycled aggregates for concrete production to reduce potential environmental load is significant. This suggests adoption of local recycled aggregates is an important strategy for the development of sustainable construction in Singapore.

A practical and efficient synthesis of phosphatidylinositol pentamannoside (PIM5) was achieved based on a five-component one-pot sequential glycosylation protocol with exclusive regio- and stereo-selectivity. Two regioselective sequential glycosylations on inositol and p-tolyl thioglycosides as the sole type of building blocks made this protocol to avoid the tedious protective group manipulations. This synthetic strategy provides access to other important glycolipids with similar structures.