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In this article, a new optical fiber humidity sensor based on the iridescent chiral-oriented cellulose nanocrystals (CNCs)/polyethylene oxide (PEO) (referred as CP) nanocomposite films was proposed. The CP composites were prepared by evaporation-induced self-assembly (EISA), and the material characteristics of the composites were performed by fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), polarizing optical microscope (POM), scanning electron microscope (SEM), and ultraviolet–visible spectroscopy (UV-vis). The CP films exhibited uniform structural color of the nematic liquid crystal regulated by the content of PEO. Then, CP composite as humidity sensing material was deposited on the sensing fiber. Based on the Mach–Zehnder structure, the as-fabricated optical fiber humidity sensor produced an interference peak intensity movement associated with the change of refractive index (RI) and thickness of sensitive material. The structure and principle of the fiber sensor were described in detail, and the humidity sensing performances, including humidity sensitivity, response time, and stability, were comprehensively studied and the humidity sensing mechanism was discussed. An ultrahigh sensitivity of 0.64 dB% RH in the range of 30%–85% RH can be obtained, which is superior to other optical fiber humidity sensor. Additionally, the sensor has the advantages of fast response and recovery, good stability, and easy to fabricate and has potential applications in the field of remote online humidity monitoring.

Electro-Fenton (EF) technology has been recognized as a highly promising electrochemical advanced oxidation process. Promoting effective contact between active species and contaminant is crucial in electrocatalysis. Herein, we had innovatively designed a unique nanozymes in the form of hemp-ball-like structures, consist of the uniform growth of Fe3O4nanoparticles on nitrogen-doped nano hollow carbon spheres (NHCS). This catalyst was employed in a flow-through EF system with carbon felt (CF) filters serving as the work electrode. The active sites were fully exposed through the ultradispersed Fe3O4nanoparticles, and the NHCS facilitated efficient cycling of Fe3+/Fe2+. The results showed that the generation capacity of hydroxyl radicals (·OH) was enhanced, and the oxidation flux reached 370.080 mg h−1m−2with low energy consumption. The superiority of the hollow carrier was proved by the degradation results and COMSOL calculation for various carbon carriers. Moreover, the active catalyst exhibited adaptability in complex water matrices. This study offers a new perspective to synergize nanomaterials, EF reactions and flow-type systems.

Polymer waveguide devices have attracted increasing interest in several rapidly developing areas of broadband communications since they are easily adaptable to on-chip integration and promise low propagation losses. As a key member of the waveguide gain medium, lanthanide doped nanoparticles have been intensively studied to improve the downconversion luminescence. However, current research efforts are almost confined to erbium-doped nanoparticles and amplifiers operating at the C-band; boosting the downconversion luminescence of Tm3+for S-band optical amplification still remains a challenge. Here we report a Tb3+-induced deactivation control to enhance Tm3+downconversion luminescence in a stoichiometric Yb lattice without suffering from concentration quenching. We also demonstrate their potential application in an S-band waveguide amplifier and record a maximum optical gain of 18 dB at 1464 nm. Our findings provide valuable insights into the fundamental understanding of deactivation-controlled luminescence enhancement and open up a new avenue toward the development of an S-band polymer waveguide amplifier with high gain.

Accurate influent flow rate prediction is important for operators and managers at wastewater treatment plants (WWTPs), as it is closely related to wastewater characteristics such as biochemical oxygen demand (BOD), total suspend solids (TSS), and pH. Previous studies have been conducted to predict influent flow rate, and it was proved that data-driven models are effective tools. However, most of these studies have focused on batch learning, which is inadequate for wastewater prediction in the era of COVID-19 as the influent pattern changed significantly. Online learning, which has distinct advantages of dealing with stream data, large data set, and changing data pattern, has a potential to address this issue. In this study, the performance of conventional batch learning models Random Forest (RF), K-Nearest Neighbors (KNN), and Multi-Layer Perceptron (MLP), and their respective online learning models Adaptive Random Forest (aRF), Adaptive K-Nearest Neighbors (aKNN), and Adaptive Multi-Layer Perceptron (aMLP), were compared for predicting influent flow rate at two Canadian WWTPs. Online learning models achieved the highest R2, the lowest MAPE, and the lowest RMSE compared to conventional batch learning models in all scenarios. The R2values on testing data set for 24-h ahead prediction of the aRF, aKNN, and aMLP at Plant A were 0.90, 0.73, and 0.87, respectively; these values at Plant B were 0.75, 0.78, and 0.56, respectively. The proposed online learning models are effective in making reliable predictions under changing data patterns, and they are efficient in dealing with continuous and large influent data streams. They can be used to provide robust decision support for wastewater treatment and management in the changing era of COVID-19 and also under other unprecedented emergencies that could change influent patterns.

The interplay between mechanoresponses and a broad range of fundamental biological processes, such as cell cycle progression, growth and differentiation, has been extensively investigated. However, metabolic regulation in mechanobiology remains largely unexplored. Here, we identified glucose transporter 1 (GLUT1)—the primary glucose transporter in various cells—as a novel mechanosensitive gene in orthodontic tooth movement (OTM). Using an in vivo rat OTM model, we demonstrated the specific induction of Glut1 proteins on the compressive side of a physically strained periodontal ligament. This transcriptional activation could be recapitulated in in vitro cultured human periodontal ligament cells (PDLCs), showing a time- and dose-dependent mechanoresponse. Importantly, application of GLUT1 specific inhibitor WZB117 greatly suppressed the efficiency of orthodontic tooth movement in a mouse OTM model, and this reduction was associated with a decline in osteoclastic activities. A mechanistic study suggested that GLUT1 inhibition affected the receptor activator for nuclear factor-κ B Ligand (RANKL)/osteoprotegerin (OPG) system by impairing compressive force-mediated RANKL upregulation. Consistently, pretreatment of PDLCs with WZB117 severely impeded the osteoclastic differentiation of co-cultured RAW264.7 cells. Further biochemical analysis indicated mutual regulation between GLUT1 and the MEK/ERK cascade to relay potential communication between glucose uptake and mechanical stress response. Together, these cross-species experiments revealed the transcriptional activation of GLUT1 as a novel and conserved linkage between metabolism and bone remodelling. A glucose-transporting protein is key to helping teeth respond to orthodontic implants, say researchers in China. Implants apply forces to teeth and the periodontal ligament (PDL) that holds them in place, causing bone to grow on one side and be absorbed into the body on the other. Yanheng Zhou and co-workers at Peking University in Beijing showed that GLUT1, a protein that transports glucose through cell membranes, was greatly upregulated in rat, mouse and human PDL cells subjected to mechanical force. They also injected some of the mice with a GLUT1 inhibitor and found that the treatment greatly decreased the distance moved by the teeth. This could be attributed to a decline in the activity of cells that break down bone tissue and a failure in signalling channels when GLUT1 is inhibited.

The Fe/Cu electrode, prepared via a cathodic electro-deposition method, was applied as cathode material for electrochemical denitrification and achieved an enhanced NO3[?]-N removal efficiency. The Fe/Cu electrode was characterized by SEM and EDS. The results showed that nano-Fe particles were evenly distributed on the surface of Cu foam. Compared with Cu foam (24.3%) and Fe (76.0%), the Fe/Cu electrode reached a much higher nitrate removal efficiency (98.6%) within 90 min. Influencing factors of electrolysis such as initial NO3[?]-N concentration, current density, pH and temperature were further studied, showing that high current density and temperature were conductive to NO3[?]-N removal. What's more, effect of Cl[?] on decreasing NH4+-N generation and promoting TN removal was investigated thoroughly. Result presented that addition of 1.0 g L[?]1 Cl[?] greatly decreased NH4+-N generation, leading to a 98.2% TN removal efficiency after 3 h treatment. Based on the analysis experimental results, a possible pathway of nitrate electro-reduction was proposed. Additionally, the Fe/Cu composite electrode maintained excellent efficiency and qualified iron leaching, demonstrating its potential application in the treatment of nitrate contaminated water.

Organ development requires complex signaling by cells in different tissues. Epithelium and mesenchyme interactions are crucial for the development of skin, hair follicles, kidney, lungs, prostate, major glands, and teeth. Despite myriad literature on cell–cell interactions and ligand–receptor binding, the roles of extracellular vesicles in epithelium–mesenchyme interactions during organogenesis are poorly understood. Here, we discovered that ∼100 nm exosomes were secreted by the epithelium and mesenchyme of a developing tooth organ and diffused through the basement membrane. Exosomes were entocytosed by epithelium or mesenchyme cells with preference by reciprocal cells rather than self-uptake. Exosomes reciprocally evoked cell differentiation and matrix synthesis: epithelium exosomes induce mesenchyme cells to produce dentin sialoprotein and undergo mineralization, whereas mesenchyme exosomes induce epithelium cells to produce basement membrane components, ameloblastin and amelogenenin. Attenuated exosomal secretion by Rab27a/b knockdown or GW4869 disrupted the basement membrane and reduced enamel and dentin production in organ culture and reduced matrix synthesis and the size of the cervical loop, which harbors epithelium stem cells, in Rab27aash/ashmutant mice. We then profiled exosomal constituents including miRNAs and peptides and further crossed all epithelium exosomal miRNAs with literature-known miRNA Wnt regulators. Epithelium exosome-derived miR135a activated Wnt/β-catenin signaling and escalated mesenchymal production of dentin matrix proteins, partially reversible by Antago-miR135a attenuation. Our results suggest that exosomes may mediate epithelium–mesenchyme crosstalk in organ development, suggesting that these vesicles and/or the molecular contents they are transporting may be interventional targets for treatment of diseases or regeneration of tissues.

The asymmetric allylboration of aldehydes with pinacolallylboronates catalyzed by 1,1′‐spirobiindane‐7,7′‐diol (SPINOL) based phosphoric acids is described. 6,6′‐Bis(2,4,6‐triisopropylphenyl)SPINOL‐based phosphoric acid was found to be a general, highly enantioselective catalyst for such allylboration reactions and excellent enantioselectivities were obtained for different types of aldehydes including aromatic aldehydes, α,β‐unsaturated aldehydes, propargylic aldehydes, and aliphatic aldehydes.

AbstractIn this study, a fuzzy robust credibility-constrained programming (FRCCP) is developed and applied to the planning for waste management systems. It incorporates the concepts of credibility-based chance-constrained programming and robust programming within an optimization framework. The developed method can reflect uncertainties presented as possibility-density by fuzzy-membership functions. Fuzzy credibility constraints are transformed to the crisp equivalents with different credibility levels, and ordinary fuzzy inclusion constraints are determined by their robust deterministic constraints by setting α-cut levels. The FRCCP method can provide different system costs under different credibility levels (λ). From the results of sensitivity analyses, the operation cost of the landfill is a critical parameter. For the management, any factors that would induce cost fluctuation during landfilling operation would deserve serious observation and analysis. By FRCCP, useful solutions can be obtained to provide decision-making support for long-term planning of solid waste management systems. It could be further enhanced through incorporating methods of inexact analysis into its framework. It can also be applied to other environmental management problems.

The Fe/Cu electrode, prepared via a cathodic electro-deposition method, was applied as cathode material for electrochemical denitrification and achieved an enhanced NO3−-N removal efficiency. The Fe/Cu electrode was characterized by SEM and EDS. The results showed that nano-Fe particles were evenly distributed on the surface of Cu foam. Compared with Cu foam (24.3%) and Fe (76.0%), the Fe/Cu electrode reached a much higher nitrate removal efficiency (98.6%) within 90 min. Influencing factors of electrolysis such as initial NO3−-N concentration, current density, pH and temperature were further studied, showing that high current density and temperature were conductive to NO3−-N removal. What's more, effect of Cl−on decreasing NH4+-N generation and promoting TN removal was investigated thoroughly. Result presented that addition of 1.0 g L−1Cl−greatly decreased NH4+-N generation, leading to a 98.2% TN removal efficiency after 3 h treatment. Based on the analysis experimental results, a possible pathway of nitrate electro-reduction was proposed. Additionally, the Fe/Cu composite electrode maintained excellent efficiency and qualified iron leaching, demonstrating its potential application in the treatment of nitrate contaminated water.