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ABSTRACTWe propose the Jaccard matrix (JM) and the Jaccard cell (JC), define them as the extended concepts of the Jaccard index, and theoretically and numerically analyze them. The data on the Euclidean plane can derive the JM as a sparse matrix. We show the JC inherits the feature of similarity of the Jaccard index as the exponential function of mutual information. We theoretically and numerically confirm that the local correlation coefficient of the data on the Euclidean plane relates the JC to the mutual information. Although one could potentially select an arbitrary cell size of the grid to make the JM, the knowledge we can obtain from the matrix decreases if the cell size is too big or too small to distinguish the data clusters appropriately. Therefore, the JM needs a computational procedure to determine the cell size within the appropriate scale. Maximizing the variance of the JCs supports determining the unique cell size, which value locates in the middle range of the parabolic function of the cell-size parameter. The JM could derive an index extracting nonlinear correlation of the data. The maximized standard deviation of the JCs as such an index is a decreasing function of the noise scale of the data under the constraint conditions. The ability to determine the homogeneous rectangular grid pattern of the JM might be a significant feature for finding nonlinear correlation. We would summarize this study as that of a nonlinear filter working as an efficient component of explainable AI and statistics.

For quick, noninvasive, and high-sensitivity surface analysis of foods and agricultural products, a touch sensor was developed and applied to sheath-flow probe electrospray ionization/mass spectrometry (sfPESI/MS). Upon making contact with the sample, the probe stopped by detecting the current flowing through the circuit and analytes on the sample surface were extracted in the solvent preloaded in the plastic capillary. By lifting up the probe to the default position, an electrospray ionization mass spectrum of the sample was obtained. By scanning the sample stage using a programming tool, a point analysis of targeted positions of biological samples with a spot diameter of ≤0.3 mm was achieved. It took less than 10 s for one sample spot. This method was applied to various plants and animal tissues.

In the previous work, sheath-flow probe electrospray ionization (sfPESI) equipped with a touch sensor was developed for conducting samples. In this work, a capacitiance-sensitive touch sensor that can be applicable to samples prepared in a nonconducting plastic multiwell plate was developed. The radiofrequency with 5 kHz and 4.5 Vppwas applied to the metal substrate on which the plastic plate was placed. The probe tip stopped at the position where it touched the surface of the liquid solution prepared in the plastic multiwell plate by detecting the displacement current flowing through the capacitance of the circuit. By coupling a nondisposable sfPESI probe with a table-top 3-axis robot, consecutive analysis of peptides, proteins, drugs, and real samples was performed. The carry-over by the consecutive analyses was suppressed to minimal by cleansing the probe tip using the solvent of water/methanol/acetonitrile (1/1/1).

Major challenges are encountered when using high-water-content clays as construction materials owing to their low shear strength and high compressibility. Processes, such as sun drying and stabilization using chemical agents, can address the problems met with these clays during their conveyance and reuse. However, natural dehydration is a time-consuming process, and chemical stabilization can lead to an increase in the hydrogen ion index (pH) of the surrounding environment. Thus, the aim of this study is to improve the performance of high-water-content clay using a combination of green and byproduct materials, specifically bamboo chips and fly ash, which are cost-effective and eco-friendly. No previous study has attempted to design a mixture for the purpose of improving the performance of clay based on the water absorption and retention performance of stabilizers. In this study, the water absorption and retention rate (Wab), which is the mass of the water absorbed and retained by 1 g of each stabilizer, was measured by removing the unabsorbed and unretained water through filtration under vacuum suction. A series of Cone Index tests were conducted on clay, separately treated with bamboo chips and fly ash, and the tests demonstrated a correlation among the Cone Index (qc), Wab, and amount of stabilizer added (Ast). A novel mixture design was proposed for hybrid-treated clay, using the two types of stabilizers in the composite, based on parameter β, which is defined as the sum of the product (Wab/100)×(Ast/100) of each stabilizer used in the hybrid-treated clay. The results of the Cone Index tests performed on the hybrid-treated clay showed that the proposed mixture design can predict the combinations of certain amounts of each stabilizer needed to attain the target qcwith minimal errors. The results of pH measurement tests indicated that the hybrid-treated clays produced by the proposed mixture design were more eco-friendly than fly ash-treated clays. Furthermore, the theoretical maximum CO2fixation capacities of the hybrid-treated clays were evaluated to assess their feasibility as CO2-fixing materials.

This study aimed to address and overcome the inherent challenges associated with the influence of primary curing on the consistency, compaction, and strength attributes of clays treated with biomass ash, specifically palm kernel shell ash (PKSA) and rice husk ash (RHA), for stabilization. Primary curing refers to the time from the addition of PKSA or RHA to the clay until its use for fill or backfill purposes. This study explores the effect of curing on the water absorption capacities of PKSA and RHA to elucidate the treatment mechanisms that shape the characteristics of the treated clays. Wab, which is the amount of water absorbed by 1g of each stabilizer, was determined using the suction filtration technique. PKSA exhibited a significant increase in Wabwith an increase in the curing period t. Wabof RHA showed no significant variation with t.The water absorption mechanisms of each stabilizer were successfully demonstrated using scanning electron microscopy (SEM) images and X-ray diffraction (XRD) patterns. It was also observed that the impact of primary curing on the limit states, compaction, and strength of the clays treated with PKSA and RHA differed significantly. The observed differences are consistent with the variation in Wabwith respect to tbetween PKSA and RHA. The test results also suggest that changes in the free water content of the clays owing to water absorption by PKSA and RHA are closely related to changes in the properties of the PKSA- and RHA-treated clays. Parameter βrepresents the product of Waband the addition ratio of each stabilizer, A, relative to the mass of the dry clay. The contributions of βto the limit states, compaction, and strength attributes of PKSA- and RHA-treated clays were much more significant than those of A.

The objective of this study was to test the original speciation of silver (Ag) in eight different commercially available personal care products and investigate the chemical transformation of Ag during exposure to two types of synthetic greywater. The antimicrobial activity of the products was examined to determine the relationship between Ag content and speciation with the antibacterial functionality of the products. The Ag content of each product was quantified and X-ray absorption near-edge structure (XANES) analysis was used to investigate the initial speciation in the products and the changes occurring upon mixture with greywater. The results showed that the total Ag concentration in the products ranged from 17 to 30 mg kg−1, and was usually below the value reported on the label. Analyses revealed the complexity of Ag speciation in these products and highlighted the importance of characterisation studies to help elucidate the potential risks of nano-Ag in the environment. The antibacterial results confirmed that the antibacterial efficacy of the products depends on the concentration, form and speciation of Ag in the products, but is also significantly affected by product formulation. For instance, many of the products contained additional bactericidal ingredients, making it difficult to determine how much of the bactericidal effect was due directly to the Ag content/species. This paper offers some suggestions for standard methodologies to facilitate cross-comparison of potential risks across different studies and nano-enabled products.

To utilize industrial by-products in construction projects, soil stabilization using paper sludge ash-based stabilizers (PSASs) has recently been developed. PSASs can be manufactured by insolubilizing the heavy metals in original paper sludge (PS) ash, which is a waste product emitted from paper mills. This study assessed the durability of clays treated with PSASs in wet-dry or dry-wet environments through various evaluation tests. Initially, the particle size distributions (PSDs) in the clays that had undergone various pretreatments were assessed. Then, unconfined compression tests were performed on the treated clays that had undergone dry and wet curing cycles using demolded specimens. Finally, cone index tests were carried out on the treated clays that had undergone dry and wet curing cycles while the samples were constrained in molds. Based on the test results, the durability assessment of the clays treated with PSASs was discussed, considering the specifics of each evaluation test and contrasting the findings with those obtained for clays treated with cement. The generated PSDs were found to contain more fine particles as the time spent washing the samples prior to sieving was increased. The findings indicated that PSAS-treated clays will eventually become muddy, even though it is unlikely that these treated clays will ever be subjected to washing with water while being stirred after construction. The unconfined compression test results also demonstrated that, after several dry-wet cycles, the strength of the PSAS-treated specimens had decreased. It was revealed that clays treated with PSASs might be less resistant to dry-wet curing cycles than those treated with cement. However, PSAS-treated samples using unconfined compression test specimens are still being investigated and are a topic of debate because the strength development mechanisms of PSASs and cement are not similar. To address this issue, a series of cone index tests were conducted on samples treated with PSASsto examine the change in strength caused by the dry-wet curing process. The results of the cone index tests were different from those of the unconfined compression tests. The cone index test results revealed that the samples must be constrained during the assessment tests in order to assess the durability of PSAS-treated soils subjected to dry-wet curing. In addition, it was proposed in this study that the idea of maturity would be applicable to PSAS-treated soils with a range of curing temperatures and curing times as long as the soils were constrained during the assessment tests.

Increasing consumer use of engineered nanomaterials has led to significantly increased efforts to understand their potential impact on the environment and living organisms. Currently, no individual technique can provide all the necessary information such as their size, distribution, and chemistry in complex biological systems. Consequently, there is a need to develop complementary instrumental imaging approaches that provide enhanced understanding of these “bio-nano” interactions to overcome the limitations of individual techniques. Here we used a multimodal imaging approach incorporating dark-field light microscopy, high-resolution electron microscopy, and nanoscale secondary ion mass spectrometry (NanoSIMS). The aim was to gain insight into the bio-nano interactions of surface-functionalized silver nanoparticles (Ag-NPs) with the green algae Raphidocelis subcapitata, by combining the fidelity, spatial resolution, and elemental identification offered by the three techniques, respectively. Each technique revealed that Ag-NPs interact with the green algae with a dependence on the size (10 nm vs60 nm) and surface functionality (tannic acid vsbranched polyethylenimine, bPEI) of the NPs. Dark-field light microscopy revealed the presence of strong light scatterers on the algal cell surface, and SEM imaging confirmed their nanoparticulate nature and localization at nanoscale resolution. NanoSIMS imaging confirmed their chemical identity as Ag, with the majority of signal concentrated at the cell surface. Furthermore, SEM and NanoSIMS provided evidence of 10 nm bPEI Ag-NP internalization at higher concentrations (40 μg/L), correlating with the highest toxicity observed from these NPs. This multimodal approach thus demonstrated an effective approach to complement dose–response studies in nano-(eco)-toxicological investigations.

With the growing availability and use of copper‐based nanomaterials (Cu‐NMs), there is increasing concern regarding their release and potential impact on the environment. In this study, the short‐term (≤5 d) aging profile and the long‐term (135 d) speciation of dissolved Cu, copper oxide, and copper sulfide nanoparticles (CuO‐NPs and CuS‐NPs) were investigated in five different soils using X‐ray absorption spectroscopy. Soil pH was found to strongly influence the short‐term chemistry of the Cu‐NMs added at 100 mg kg−1above background. Low pH soils promoted rapid dissolution of CuO‐NPs that effectively aligned their behavior to that of dissolved Cu within 3 d. In higher pH soils, CuO‐NPs persisted longer due to slower dissolution in the soil and resulted in contrasting short‐term speciation compared with dissolved Cu, which formed copper hydroxides and carbonates that were reflective of the soil chemistry. Organic matter appeared to slow the dissolution process, but in the long term, the speciation of Cu added as dissolved Cu, CuO‐NPs, and CuS‐NPs were found to be same for each soil. The results imply that, in the short term, Cu‐NMs may exhibit unique behavior in alkaline soils compared with their conventional forms (e.g., in the event of an adverse leaching event), but in the long term (≥135 d), their fates are dictated by the soil properties, are independent of the initial Cu form, and are likely to present minimal risk of nanospecific Cu‐NM impact in the soil environment for the concentration studied here. Short‐term reactions of Cu are form (dissolved or nanoparticle) and soil chemistry dependent.In low pH soils, CuO‐NPs dissolved rapidly and behaved similarly to dissolved Cu.CuO‐NPs persisted longer in alkaline soils and soils with high organic matter content.In the long term, Cu, CuO‐NPs, and CuS‐NPs transform into Cu bound to FeO(OH) or NOM.Chemical fate of Cu added to soils is largely independent of the original Cu form.

This study analyzes the expression and the function of Xenopus msx-1(Xmsx-1) in embryos, in relation to the ventralizing activity of bone morphogenetic protein-4 (BMP-4). Expression of Xmsx-1was increased in UV-treated ventralized embryos and decreased in LiCl-treated dorsalized embryos at the neurula stage (stage 14). Whole-mount in situ hybridization analysis showed that Xmsx-1is expressed in marginal zone and animal pole areas, laterally and ventrally, but not dorsally, at mid-gastrula (stage 11) and late-gastrula (stage 13) stages. Injection of BMP-4 RNA, but not activin RNA, induced Xmsx-1 expression in the dorsal marginal zone at the early gastrula stage (stage 10+), and introduction of a dominant negative form of BMP-4 receptor RNA suppressed Xmsx-1expression in animal cap and ventral marginal zone explants at stage 14. Thus, Xmsx-1 is a target gene specifically regulated by BMP-4 signaling. Embryos injected with Xmsx-1 RNA in dorsal blastomeres at the 4-cell stage exhibited a ventralized phenotype, with microcephaly and swollen abdomen. Histological observation and immunostaining revealed that these embryos had a large block of muscle tissue in the dorsal mesodermal area instead of notochord. On the basis of molecular marker analysis, however, the injection of Xmsx-1RNA did not induce the expression of α-globin, nor reduce cardiac α-actin in dorsal marginal zone explants. Furthermore, a significant amount of α-actin was induced and α-globin was turned off in the ventral marginal zone explants injected with Xmsx-1. These results indicated that Xmsx-1 is a target gene of BMP-4 signaling, but possesses a distinct activity on dorsal-ventral patterning of mesodermal tissues.