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With the development of graph neural networks, how to handle large-scale graph data has become an increasingly important topic. Currently, most graph neural network models which can be extended to large-scale graphs are based on random sampling methods. However, the sampling process in these models is detached from the forward propagation of neural networks. Moreover, quite a few works design sampling based on statistical estimation methods for graph convolutional networks and the weights of message passing in GCNs nodes are fixed, making these sampling methods not scalable to message passing networks with variable weights, such as graph attention networks. Noting the end-to-end learning capability of neural networks, we propose a learnable sampling method. It solves the problem that random sampling operations cannot calculate gradients and samples nodes with an unfixed probability. In this way, the sampling process is dynamically combined with the forward propagation process of the features, allowing for better training of the networks. And it can be generalized to all message passing models. In addition, we apply the learnable sampling method to GNNs and propose two models. Our method can be flexibly combined with different graph neural network models and achieves excellent accuracy on benchmark datasets with large graphs. Meanwhile, loss function converges to smaller values at a faster rate during training than past methods. [ABSTRACT FROM AUTHOR]

Glioblastoma represents one of the most aggressive cancers, characterized by severely limited therapeutic options. Despite extensive investigations into this brain malignancy, cellular and molecular components governing its immunosuppressive microenvironment remain incompletely understood. Here, we identify a distinct neutrophil subpopulation, termed disease-specific suppressive granulocytes (DSSGs), present in human glioblastoma and lower-grade gliomas. DSSGs exhibit the concurrent expression of multiple immunosuppressive and immunomodulatory signals, and their abundance strongly correlates with glioma grades and poor clinical outcomes. Genetic disruption of neutrophil recruitment in immunocompetent mouse models of gliomas, achieved through Cxcl1 knockout in glioma cells or host-specific Cxcr2 deletion or diphtheria toxin A-mediated neutrophil depletion, can significantly enhance antitumor immunity and prolong survival. Further, we reveal that the skull bone marrow and meninges can be the primary sources of neutrophils and DSSGs in human and mouse glioma tumors. These findings demonstrate a critical mechanism underlying the establishment of the immunosuppressive microenvironment in gliomas. [Display omitted] • Immunosuppressive neutrophils are distinctly present within human and mouse glioma tumors • Neutrophils in glioma tumors express multiple immunosuppressive and immunomodulatory signals • Blockage of neutrophil responses improves the survival in mouse models of lethal gliomas • Neutrophils can be recruited into glioma tumors from the skull bone marrow and the meninges Zhao et al. report the identification and characterization of immunosuppressive neutrophils within human and mouse glioma tumors. The presence of such disease-specific suppressive granulocytes (DSSGs) correlates with glioma grades and poor clinical outcomes. Blockage of DSSGs, which partly originate from the skull bone marrow and meninges, strongly delays tumor progression. [ABSTRACT FROM AUTHOR]

The excellent dielectric constant (ε r) and breakdown strength (E b) of dielectric nanocomposites are the necessary conditions for their excellent energy storage properties (ESPs) in microelectronics and power systems. In recent years, inorganic nanofillers and multilayer structure design have provided an efficient way to improve the ESPs of dielectric composites. Herein, we selected 0.8Bi 0.5 (Na 0.82 K 0.18) 0.5 TiO 3 -0.2Sr(Sc 0.5 Nb 0.5)O 3 cecamic nanoparticles (BNKT-SSN NPs) with high ε r and low loss as nanofillers, and prepare novel trilayer structured BNKT-SSN/P(VDF-HFP) nanocomposites to improve the ε r and E b. The investigated phenomena demonstrate that due to the contribution of BNKT-SSN NPs incorporation and interfacial polarization between neighboring layers, the ε r and E b of the trilayer structured BNKT-SSN/P(VDF-HFP) nanocomposites are enhanced while the dielectric loss (tan δ) and leakage current density are suppressed. It is worth noting that the E b is measured up to 650 MV m−1 when the intermediate layer fillers BNKT-SSN NPs of the trilayer structured nanocomposite is 0.75 vol%, and the discharged energy density (U d) and energy efficiency (η) are 25.79 J cm−3 and 70.07 %, respectively. In this work, it's demonstrates that the incorporation of inorganic ceramic fillers and the trilayer structured design provide a feasible approach of improving the ESPs of dielectric nanocomposites. [Display omitted] • The ceramic and sandwich structure work together to improve the ε r and E b. • The electric field distribution is simulated by finite element method. • The insulation and mechanical properties of nanocomposites are enhanced. • The optimal U d and η of the composite at 650 MV m−1, are 25.79 J cm−3 and 70.07 %. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is one of the essential elements for plant growth and is involved in the process of photosynthesis and seed germination. Herein, we applied two Mn-based nanoparticles, MnO 2 and Mn 3 O 4 , to the soil to investigate their effects on radish growth, antioxidant system, and nutrients. The radish plant height after treatment with 10 mg/kg of MnO 2 and Mn 3 O 4 NPs were increased, compare to the control. In radish's shoot, MnO 2 NPs at high concentrations (100 mg/kg) increased MDA activity by 58 % compared to the control group, while exposure to Mn 3 O 4 NPs at the same concentration decreased MDA activity by 14 %. The nutrient content of radishes, such as soluble sugar and vitamin C, was improved. Moreover, single particle inductively coupled plasma mass spectrometry (SP ICP-MS) was used to understand the patterns of migration of Mn-based NPs in radish and subsequent impact on nutrients. We found that Mn-based NPs accumulated mainly in the roots of radish. Interestingly, the accumulation characteristics of MnO 2 NPs and Mn 3 O 4 NPs were different. MnO 2 NPs accumulated more in radish leaves than in fruits, while the accumulation of Mn 3 O 4 NPs gradually decreased from roots to leaves. Finally, we determined the mineral element content of the leaves, fruits, and roots of radish, and found that the uptake of main metallic mineral elements (e.g. Cu, Fe, Mg, Zn, Na, K) was inhibited by the application of Mn-based NPs. These findings underscore the importance of considering species and multifaceted impacts of Mn-based NPs as nanofertilizers for their wide application in agriculture. [Display omitted] • Mn NPs at 50 mg/L enhanced root elongation and seed vigour in radish. • Low concentrations of Mn NPs promote radish growth. • Mn NPs are able to regulate the activity of antioxidant enzymes. • SP ICP-MS revealed that radish roots as the major site of Mn NPs accumulation. • Mn NPs inhibited the uptake of metallic elements by radish. [ABSTRACT FROM AUTHOR]

This paper aims to explore the cooperative use of agricultural waste and nanomaterials to improve environmental sustainability. The introduction highlights global environmental challenges and the objectives of integrating the two are highlighted. Valorization of agricultural waste is considered to reduce waste generation, while nanomaterials act as conversion catalysts that help to increase the efficiency of waste conversion and environmental remediation. In addition, synergistic approaches are discussed, including the combination of agricultural waste and nanomaterials, as well as the concept of enhanced resource management. The paper also presents case studies that demonstrate the success of such synergistic applications in pollution control and environmental remediation. Despite the challenges and risks, this approach can provide new ways to create more sustainable and resilient environments through the integration of resources, interdisciplinary cooperation and policy support. [Display omitted] • Combining nanomaterials into agricultural waste management is a sustainable approach transforming waste to treasure. • Nanomaterial catalysts can improve waste conversion efficiency and pollution control. • Challenges still remain for harnessing synergies for resilient environmental solutions. [ABSTRACT FROM AUTHOR]

Flow field-flow fractionation (FlFFF) is a gentle technique that does not require a stationary phase and allows for the non-destructive isolation/separation of biomacromolecules and bioparticulate species in biological samples. Given the large separation range (i.e., 1 nm to 100 μm), FlFFF is theoretically applicable for the full spectrum of vital biological species. We provide an overview of the basic separation mechanism and development of FlFFF, followed by discussion of the current applications of FlFFF in the characterization of representative biomacromolecules, bionanoparticles, and biomicroparticles in biological samples, particularly new advances in the last 5 years. Furthermore, the emerging applications of FlFFF in extracellular vesicle research are systematically discussed for the first time. Finally, we posit that more efforts are needed to direct the separation and characterization of biomacromolecules, bionanoparticles, and biomicroparticles using FlFFF. Overall, this review provides current status, developmental trends, and further advances of FlFFF in life science. • Full-spectrum separation of biological species by two FlFFF separation modes. • The potential of FlFFF in disease diagnosis and treatment. • Very recent use of FlFFF in the separation and characterization of EVs. • Some perspectives and future directions of FlFFF in life science. [ABSTRACT FROM AUTHOR]

Rice is known to accumulate cadmium (Cd) in its grains, causing a severe threat to billions of people worldwide. The possible phytotoxicity and mechanism of 50–200 mg/L hydroxyapatite NPs (nHA), iron oxide NPs (nFe2O3) or nano zero valent iron (nZVI) co-exposed with Cd (100 μM) in rice seedlings were investigated. Three types of nanoparticles significantly reduced the bioaccumulation of Cd in rice shoots by 16–63%, with nZVI showing the greatest effect, followed by nHA and nFe2O3. A decrease in Cd content in the roots was observed only in the nZVI treatment, with values ranging from 8 to 19%. Correspondingly, nZVI showed the best results in promoting plant growth, increasing rice plant height, shoot and root biomass by 13%, 29% and 42%. In vitro studies showed that nZVI reduced the content of Cd in the solution by 20–52% through adsorption, which might have contributed to the immobilization of Cd in root. Importantly, the nZVI treatment resulted in 267% more iron plaques on the root surface, which acted as a barrier to hinder the entry of Cd. Moreover, all three nanoparticles significantly reduced the oxidative stress induced by Cd by regulating phytohormones, phytochelatin, inorganic homeostasis and the expression of genes associated with Cd uptake and transport. Overall, this study elucidates for the first time the multiple complementing mechanisms for some nanoparticles to reduce Cd uptake and transport in rice and provides theoretical basis for applying nanoparticles for reducing Cd accumulation in edible plants. [Display omitted] • NZVI reduced Cd accumulation in rice shoot by 75–80% due to strong sorption. • NZVI increased the amount of iron plaque by 267%, blocking the root uptake of Cd. • Hormones, nutrients homeostasis and chelators are essential in mitigating Cd stress. • Mechanistic differences in different NPs are elucidated for the first time. [ABSTRACT FROM AUTHOR]

• The same-sized AgNPs with different coatings were separated by BCyElFFF. • NOM corona on AgNPs was identified by changes in their elution times in BCyElFFF. • NOM corona structures identified were in good agreement with HRTEM results. • NOM corona significantly improved the survival rate of E. coli exposed to AgNPs. Natural organic matter (NOM) readily interacts with nanoparticles, leading to the formation of NOM corona structures on their surface. NOM corona formation is closely related to the surface coatings and bioavailability of nanoparticles. However, the mechanism underlying NOM corona formation on silver nanoparticles (AgNPs) remains largely unknown due to the lack of effective analytical methods for identifying the changes in the AgNP surface. Herein, the separation ability of biased cyclical electrical field-flow fractionation (BCyElFFF) for same-sized polyvinyl pyrrolidone-coated and poly(ethylene glycol)-coated silver nanoparticles (AgNPs) with different electrophoretic mobilities was evaluated under various electrical conditions. Then, the mechanism behind the NOM corona formation on these AgNP surfaces was elucidated based on the changes in the elution time and off-line characterization of the collected fractions during their elution time in a BCyElFFF run. Finally, the survival rates of E. coli exposed to polyvinyl pyrrolidone-coated and poly(ethylene glycol)-coated AgNPs with or without NOM collected during repeated BCyElFFF runs were observed to increase with increasing NOM concentration, clearly demonstrating the negative effect of NOM corona structures on the bioavailability of AgNPs. These findings highlight the powerful separation and isolation ability of BCyElFFF in studying the transformation and fate of nanoparticles in aqueous environments. [Display omitted] [ABSTRACT FROM AUTHOR]

Mixed hematopoietic chimerism can promote immune tolerance of donor-matched transplanted tissues, like pancreatic islets. However, adoption of this strategy is limited by the toxicity of standard treatments that enable donor hematopoietic cell engraftment. Here, we address these concerns with a non-myeloablative conditioning regimen that enables hematopoietic chimerism and allograft tolerance across fully mismatched major histocompatibility complex (MHC) barriers. Treatment with an αCD117 antibody, targeting c-Kit, administered with T cell-depleting antibodies and low-dose radiation permits durable multi-lineage chimerism in immunocompetent mice following hematopoietic cell transplant. In diabetic mice, co-transplantation of donor-matched islets and hematopoietic cells durably corrects diabetes without chronic immunosuppression and no appreciable evidence of graft-versus-host disease (GVHD). Donor-derived thymic antigen-presenting cells and host-derived peripheral regulatory T cells are likely mediators of allotolerance. These findings provide the foundation for safer bone marrow conditioning and cell transplantation regimens to establish hematopoietic chimerism and islet allograft tolerance. [Display omitted] • Stable mixed hematopoietic chimerism achieved without myeloablative conditioning • Chimerism confers allotolerance to MHC-mismatched islets without immunosuppression • Simultaneous hematopoietic cell and islet transplantation durably corrects diabetes • Central and peripheral tolerance mechanisms likely mediate islet allotolerance Pancreatic islet transplantation in diabetes is limited by requirements for systemic immunosuppression to prevent rejection. Chang et al. report a non-toxic bone marrow conditioning regimen targeting c-Kit that permits stable mixed hematopoietic chimerism across major histocompatibility complex barriers, promoting allotolerance to transplanted islets without systemic immunosuppression and durable diabetes correction. [ABSTRACT FROM AUTHOR]

The large-scale use of conventional pesticides and fertilizers has put tremendous pressure on agriculture and the environment. In recent years, nanoparticles (NPs) have become the focus of many fields due to their cost-effectiveness, environmental friendliness and high performance, especially in sustainable agriculture. Traditional NPs manufacturing methods are energy-intensive and harmful to environment. In contrast, synthesizing metal-based NPs using plants is similar to chemical synthesis, except the biological extracts replace the chemical reducing agent. This not only greatly reduces the used of traditional chemicals, but also produces NPs that are more economical, efficient, less toxic, and less polluting. Therefore, green synthesized metal nanoparticles (GS-MNPs) are widely used in agriculture to improve yields and quality. This review provides a comprehensive and detailed discussion of GS-MNPs for agriculture, highlights the importance of green synthesis, compares the performance of conventional NPs with GS-MNPs, and highlights the advantages of GS-MNPs in agriculture. The wide applications of these GS-MNPs in agriculture, including plant growth promotion, plant disease control, and heavy metal stress mitigation under various exposure pathways, are summarized. Finally, the shortcomings and prospects of GS-MNPs in agricultural applications are highlighted to provide guidance to nanotechnology for sustainable agriculture. [ABSTRACT FROM AUTHOR]

For the Bi–Zn and Bi–Sn–Zn systems, vacuum distillation experiments were carried out at 10 Pa. The results show that the content of Zn for the Bi–Zn system in the vapor phase could reach more than 0.999 mol fraction in vacuum distillation. The VLE (vapor-liquid equilibrium) data were correlated using the Tsuboka-Katayama's modification of the Wilson equation (T-K-Wilson). The correlation showed good agreement with experimental data. Thermodynamic consistency tests of experimental data for the binary and ternary systems were presented by the Van Ness method. The results demonstrate that VLE phase diagram is reliable for predicting the process of vacuum distillation for the systems. It provides an efficient way to guide the separation and purification of crude Zn in vacuum metallurgy • Vapor-liquid equilibria of Bi–Zn and Bi–Sn–Zn systems under vacuum condition were measured. • The T-K-Wilson equation was used to calculated activities of components. • The experimental data for the Bi–Zn and Bi–Sn–Zn systems were correlated using the T-K-Wilson equation. [ABSTRACT FROM AUTHOR]

To realize the fabrication of Ti–Mo–N coatings with novel properties predicted towards industrial applications, Mo-doped TiN coatings have been fabricated by multi-arc ion plating with varied substrate bias, and systematically characterized. The as-deposited coatings show a 1.5 at% Mo content deficit due to melting point difference between Mo and Ti elements. X-ray diffraction (XRD) and X-ray photoelectron spectrum (XPS) results show the as-deposited coatings demonstrate a fcc-TiN + bct-Ti 2 N dual phase structure, with Mo solution into TiN lattice. The hardness of TiMo 0.08 N coatings is above 31.97 GPa, which first increases then decreases slightly, peaking at 34.26 GPa. The phenomenon is correlated to the decreased (111) while enhanced (220) preferred orientation. All coatings show adhesion properties above 65 N (>100 N when bias voltage is above −50 V) and friction coefficients (COFs) below 0.24, which is attributed to the formation of lubricant MoO 3 phase in a surface tribochemical process, as confirmed by XPS and Raman spectra evidences. Electrochemical polarization curves reveal that all samples have higher corrosion potential and corrosion currents two order of magnitudes lower than the WC-Co substrates. Additionally, substrate bias voltage has little impacts on structures and properties of the coatings, which means a wide process window. • The TiMo 0.08 N coatings have hardness above 32 GPa and excellent adhesion strength. • All samples show solid lubricating effect with COFs below 0.24. • The coatings show good corrosion resistance. • The coatings demonstrate a broad substrate bias voltage window. [ABSTRACT FROM AUTHOR]

Tin pyrophosphate has been employed as a proton conductor in polymer electrolyte membranes (PEMs) at temperatures over 200 °C. However, neither the aggregation of the SnP 2 O 7 nanoparticles nor the proton conduction mechanism of the material has been clearly clarified in PEM. The present work reports a polybenzimidazole (PBI)/SnP 2 O 7 composite membrane with homogeneous distribution of the inorganic phase. The membrane is successfully fabricated by in-situ transformation of SnO 2 nanoparticles to core-shell SnP 2 O 7 nanoparticles in the PBI matrix during fuel cell operation. Further in-depth analysis shows that the core-shell SnP 2 O 7 contains a crystalline SnP 2 O 7 core, an amorphous SnP 2 O 7 intermediate layer and a gel-like outer layer mainly containing H 4 P 2 O 7. In addition, the crystal growth of the SnP 2 O 7 nucleus consumes ions from the amorphous SnP 2 O 7 layer, where the reacted ions are compensated by the diffusion of Sn4+ and P 2 O 7 4− ions from the gel-like outer layer. Also, the fuel cell with the composite membrane shows superior proton conductivity and durability compared to the pristine phosphoric acid-doped PBI membrane at 240 °C for over 50 h. That is due to the presence of H 4 P 2 O 7 in the outer layer, which contributes to high and stable proton conductivity of the core-shell SnP 2 O 7 at 220–260 °C. [ABSTRACT FROM AUTHOR]

Phosphorus-based nanomaterials (PNMs) have been reported to have substantial promise for promoting plant growth, improving plant tolerance mechanisms, and increasing resistance to pathogenic organisms. Recent scientific investigation has demonstrated that utilizing PNMs can enhance plant physiological growth, photosynthetic pigments, antioxidant system, metabolism, nutrient absorption, rhizosphere secretion, and soil nutrients activation. Previous research on PNMs mostly concentrated on calcium phosphate, zeolite, and chitosan, with little systematic summarization, demanding a thorough evaluation of PNMs' broader uses. In our current review article, we address the knowledge gap by classifying PNMs according to green synthesis methods and the valence state of phosphorus while elucidating the underlying mechanisms through which these PNMs facilitate plant growth. In addition, we also targeted some strategies to improve the bioavailability of PNMs, offering valuable insights for the future design and safe implementation of PNMs in agricultural practices. [Display omitted] • The application of phosphorus-based nanomaterials in agriculture was summarized. • The phosphorus-based nanomaterials were systematically divided. • The mechanism of phosphorus-based nanomaterials regulating plant growth was explained. • A strategy to improve the bioavailability of phosphorus-based nanomaterials was proposed. [ABSTRACT FROM AUTHOR]

Since the inception of urbanization and industrialization, emissions of volatile organic compounds (VOCs) have become serious concern due to harmful effects on terrestrial biota, serious measures must be taken to minimize the emissions of VOCs. Catalytic oxidation is considered one of the most promising technologies for removing VOCs for its low ignition temperature, high efficiency, and no secondary pollution in the process of treatment. This review summarizes progress made in the catalytic oxidation of VOCs over last ten years. We have discussed the mechanism and current advancement of non-noble metal catalysts to remove VOCs. Besides, the characteristics and the factors affecting catalytic performance of non-noble metal catalysts are comprehensively explained. The critical factors that affect the catalytic performance of catalysts mainly include preparation methods, modification technologies, and carrier materials. Therefore, future research should focus on developing efficient catalysts and performance improvement. We believe that current review will provide a great foundation and reference point for future design and development in this field. [Display omitted] [ABSTRACT FROM AUTHOR]

• CO 2 emissions in East Africa are growing exponentially at 6.5% per year. • The process of energy clean-up is slow with little emission reduction. • Economic and population growth are the most significant emission drivers. • Emission patterns and drivers vary significantly from country to country. • Locally tailored emission reductions are needed. East Africa is typical of the less developed economies that have emerged since the 21st century, whose brilliant economic miracle has also triggered the rapid growth of energy consumption and carbon dioxide emissions. However, previous carbon accounting studies have never focused on the region. Based on multi-source data, this paper rebuilt the 45-sectors carbon emission inventories of eight East African countries from 2000 to 2017, and used index decomposition analysis to quantify the drivers of growth. Here we found that overall the CO 2 emissions show a 'two-stage exponential growth' pattern, with significant heterogeneity between countries. In terms of the energy mix, technical progress in hydro and geothermal energy was almost offset by a growing appetite for oil and coal, making it the weak and valuable factor driving emissions reduction (−1.4Mt). But it was far from enough to overcome the pressure of economic and population growth, which brought about a 13Mt and 11Mt emission growth respectively from 2000 to 2017. Increasing energy intensity due to industrialization and transport development also contributed to an increment of 6.4Mt. Low-carbon policies should be tailored to local conditions and targeted at the improvement of energy efficiency and use of renewable energy so as to achieve a win-win situation between sustainable economic growth and emission reduction. [ABSTRACT FROM AUTHOR]