The change of the properties of chrysotile after ball milling in organic liquids (aromatics, alcohols, silicone oils) or water was studied by gas adsorption, electron microscopy, X-ray powder diffraction, infrared spectroscopy, differential thermal analysis, zeta potential measurements, and chemical analysis. Grinding in low viscosity organic solvents leads initially to a rapid defiberization of the asbestos bundles and to a fragmentation of the isolated fibrils. Finally, amorphization and agglomeration occur causing a drastic decrease of the specific surface area of the ground material. Grinding in water brings about a defiberization, but much more slowly than in organic solvents. Moreover, prolonged grinding in water does not significantly alter the structure of chrysotile. The efficiencies of the organic solvents, considered as grinding aids that induce fracture of the fibrils, are related to the environmental stress cracking of brittle solids (Rehbinder theory). Hence, the pertinent properties of the organic liquids are their viscosity and their cohesion energy (solubility parameter). Solvents chemisorbed on the surface of the ground chrysotile reduce the surface energy of the fracture surface and prevent aggregation. Water does not react according to Rehbinder's theory, but appears to form a protective layer around the fibrils. This hypothesis was verified by dry grinding defiberized asbestos (rapid amorphization) or by disturbing the stability of the water coating by coadsorbing alcohol on the solid surface. Alternatively, the resistance of the fibrils to fracture may be explained by Westwood's theory that grinding in water is equivalent to grinding in an alkali medium, wherein the surface charge of the chrysotile becomes negligible, and the mechanical stability of the fiber reaches a maximum.

As shown by scanning and transmission electron microscopy, halloysite in three rhyolitic tephras occurs as squat and elongate ellipsoids. Both morphologies are presumed to result from a similar lattice building mechanism. The squat ellipsoids form from allophane; the elongate ellipsoids form from feldspars. The squat ellipsoids do not possess flattened faces or spaces between books of layers at field moisture levels. Outgrowths from the squat ellipsoids are possibly due to inclusions of allophane, glass, ferrihydrite, or feldspar crystallites. Possible spiral growth of halloysite, giving curved surfaces, may be due to a continuous distribution of crystal dislocations.

By using a transmission electron microscope equipped with an energy dispersive spectrometer, it was possible to detect the morphological, structural, and chemical characteristics of individual asbestos fibers and clay minerals without any realignment of the equipment. A rapid and convenient procedure for semiquantitative analysis is proposed. Analyses are given for 21 hydrous silicates, asbestos and clay minerals, by both ordinary chemical and energy dispersive methods. The energy dispersive results were comparable to those obtained by chemical analysis. Application of this procedure to asbestos fibers proved this method to be practical and valid for characterization of asbestos in environmental and tissue samples.

Scanning electron microscopic (SEM) examination of the quartz isolated from chert of Transvaal and Swaziland, of 2000 and 3400 million year (MY) ages, respectively, in southern Africa revealed marked differences in quartz morphology. Well-defined individual euhedral quartz crystals, with polyhedral triple-point faces, were clearly evident on freshly fractured Transvaal chert surfaces as well as with the quartz isolates from the chert. The morphology and coarseness suggest crystal growth with little, if any, metamorphism; however, the δ18O values of 23.8–24.1‰ suggest crystallization temperatures of perhaps 40–45°C. In contrast, fracture surfaces of the older, strongly metamorphosed Swaziland cherts revealed a high degree of grain intergrowth which inhibited fracture between quartz grains. Quartz isolates from these showed strongly interlocked quartz crystal clusters and elongated chips of quartz with poorly defined irregular faces. Intercalation of mineral veins in the cherts on a mm scale and the intergrown character of the quartz grain boundaries provide evidence that the latter cherts have been strongly metamorphosed and recrystallized, in keeping with 14.6–15.1‰ δ18O values, corresponding to 80°C fractionation with water. The SEM micrographs of the fine quartz (1–10 µm) isolated from the Otavi dolomite formation of the 700-MY Damara System and from the 2000-MY Transvaal Dolomite Series revealed well-defined subhedral and euhedral quartz crystals of small size which, together with the 26.9–27.8‰ and 23.8‰ δ18O values, respectively, indicate that these dolomites have been affected little, if any, by post-depositional metamorphism; their crystallization temperatures fall in the range of 25–30 and 40–45°C, respectively.

Although the specific outcrop from which the original kaolin at Kauling (Gaoling) Mine, China, was collected cannot now be relocated, samples were collected and studied from the mine tunnel, country rock, and pegmatite which constitute the sources of kaolin in this region. The kaolin is a residual product of weathering. Where the parent rock was a granite the clay is a mixture of platy and elongate kaolin-group minerals, whereas from the pegmatite portion of the parent rock it is halloysite(10Â) with elongate morphology. These mineral identifications are based on X-ray powder diffractograms, scanning electron micrographs, differential thermograms, and an infrared spectrum hitherto not documented for material from this area.

Although the Kauling locality is the region for which kaolin is named, the mineral kaolinite is a defined species without a specific type locality. The 11th century Chinese locality was not mentioned in the two classic research papers defining kaolinite. The data on the Chinese kaolin, therefore, cannot be used directly to provide criteria for sharply differentiating the otherwise vague boundary between the minerals kaolinite and halloysite(7Å). Pertinent questions on these kaolin-group mineral relationships are brought into clearer focus.

Morphological analysis is a crucial preprocessing stage for building the state-of-the-art natural language processing applications. We propose a bidirectional LSTM (long short-term memory)-based approach to develop the morphological analyzer for the Gujarati language. Our morph analyzer predicts a root word and the morphological features for the given inflected word. We have experimented with two different methods for label representation for predicting morphological features: the monolithic representation method and the individual label representation method. We have also created the gold morphological dataset of 16,234 unique words for the Gujarati language. The dataset contains morpheme splitting and grammatical feature information for each inflected word. Due to the change in the label representation technique in the proposed model, the accuracy of the present baseline system is improved by a large margin. The proposed system performs very well across the POS categories without the knowledge of language-specific suffix rules.

Robots are becoming increasingly prevalent in the workplace. As Industry 5.0 pursues human-centric technologies, a greater understanding of what effects aesthetics has on those interacting with robots is needed. This paper sets out robot morphology as a way to characterise key form types, and proposes seven classifications: anthropomorphism, zoomorphism, phytomorphism, artemorphism, functiomorphism, amorphism, and neomorphism. Through an assessment of the current robot aesthetic landscape, design dimensions are identified with examples that can inform future robot design.

During nematode surveys of natural vegetation in forests of La Cima de Copey de Dota, San José, San José province, Costa Rica, a Xenocriconemella species closely resembling X. macrodora and related species was found. Integrative taxonomical approaches demonstrated that it is a new species described herein as X. costaricense sp. nov. The new species is parthenogenetic (only females have been detected) and characterised by a short body (276–404 μm); lip region with two annuli, not offset, not separated from body contour; first lip annulus partially covering the second lip annulus. Stylet thin, very long (113–133 μm) and flexible, occupying 30.5–47.8% of body length. Excretory pore located from one or two annuli anterior to one or two annuli posterior to level of stylet knobs, at 42 (37–45) μm from anterior end. Female genital tract monodelphic, prodelphic, outstretched, and occupying 35–45% of body length, with vagina slightly ventrally curved (14–18 μm long). Anus located 6–11 annuli from the tail terminus. Tail conoid and bluntly rounded terminus, the last 2–3 annuli oriented dorsally. Results of molecular characterisation and phylogenetic analyses of D2-D3 expansion segments of 28S rRNA, ITS, and partial 18S rRNA, as well as cytochrome oxidase c subunit 1 gene sequences further characterised the new species and clearly separated it from X. macrodora and other related species (X. iberica, X. paraiberica, and X. pradense).

This study mapped the trajectory of developing derivational morphological knowledge in Hebrew monolingual and Russian–Hebrew bilingual children. We investigated 2nd and 4th graders, using a two-by-two structure along the dimensions of modality (comprehension, production) and type of word (real-word, pseudo-word). Performance in the morphological analogies comprehension tasks improved with grade, and monolingual and bilingual children performed equally well. A different pattern was evident in production tasks. In real-word production, monolingual children were more accurate than bilingual children, but this group difference narrowed with age. In pseudo-word production, monolingual children used more morphological elements than bilingual children, and there was also a tendency towards group differences narrowing with age. Detailed error analyses across all tasks revealed that monolingual children recruited more morphological elements than bilingual children. We present implications for assessment of morphological knowledge, and suggest that morphological intervention is a promising avenue for promoting bilingual children’s success.

Environmental plastic pollution comprises partially degraded particles representing a continuum of sizes, shapes, polymer types and chemical compositions. Owing to their potential for biological uptake, small microplastic particles (sMP; <100 μm) and nanoplastics (NPs) are considered to be a potential risk to organisms. Understanding how sMPs and NPs behave in the environment, and how environmental matrices affect their detection, is fundamental to quantifying exposures, assessing hazards and understanding these risks. For this purpose, high-quality, well-characterised and environmentally relevant test and reference materials are crucial. The current lack of environmentally relevant sMP and NP reference materials has resulted in many studies applying commercially available spherical, homogenous and monodisperse particles, typically produced for specific purposes and without environmental relevance. There is a need for sMP and NP test/reference materials for fate and effects assessments and analytical protocol validation that more accurately represent the sMP and NP present in the environment. To date, feasible methods for producing relevant sMP and NP test materials in sufficient quantities for environmental fate and effects studies remain lacking. The current review provides an overview and comparison of the available methods, highlighting those that show the most promise for producing environmentally relevant sMP and NP with further development and optimisation.

Two new species of the genus Sectonema found in northern Iran are characterized, including morphological descriptions and molecular (18S-, 28S-rDNA) analyses. Sectonema tehranense sp. nov. is distinguished by its 7.22 – 8.53 mm long body, lip region offset by constriction and 24 – 31 μm wide with perioral lobes and abundant setae- or cilia-like projections covering the oral field, mural tooth 15.5 – 17 μm long at its ventral side, neck 1091 – 1478 μm long, pharyngeal expansion occupying 61 – 71% of the total neck length, female genital system diovarian, uterus simple and 3.9 – 4.2 times the corresponding body diameter long, transverse vulva (V = 49 – 59), tail short and rounded (44 – 65 μm, c = 99 – 162, c’ = 0.6 – 0.8), spicules 111 – 127 μm long, and 7 – 10 spaced ventromedian supplements with hiatus. Sectonema noshahrense sp. nov. displays a 4.07 – 4.73 mm long body, lip region offset by constriction and 23 – 25 μm wide with perioral lobes and abundant setae- or cilia-like projections covering the oral field, odontostyle 14 – 14.5 μm long, neck 722 – 822 μm long, pharyngeal expansion occupying 66 – 68% of the total neck length, female genital system diovarian, uterus simple and 2.4 – 2.7 times the corresponding body diameter long, transverse vulva (V = 54 – 55), tail convex conoid (39 – 47 μm, c = 91 – 111, c’ = 0.8 – 0.9), spicules 82 μm long, and seven spaced ventromedian supplements with hiatus. Molecular analyses confirm a maximally supported (Epacrolaimus + Metaporcelaimus + Sectonema) clade and a tentative biogeographical pattern, with sequences of Indolamayan taxa forming a clade separated from those of Palearctic ones. Parallel or convergent evolution processes might be involved in the phylogeny of the species currently classified under Sectonema. This genus is certainly more heterogeneous than previously assumed.

Gymnocranius indicus sp. nov. is described as a new species of the fish subfamily Monotaxinae (Sparoidea: Lethrinidae), a group of commercially important species distributed throughout the Indo-West Pacific, on the basis of 16 specimens collected from the Indian Ocean. The new species shares the following characters with its western Pacific sibling, the eyebrowed large-eye seabream, G. superciliosus: elongate body, distinctive and conspicuous dark patch above the eye, prominent forehead, moderately forked caudal fin, its lobes slightly convex inside, flank silvery, and reddish-to-red dorsal, pectoral, anal and caudal fins. However, principal component analysis based on seven morphological variables distinguished most specimens from the Indian Ocean from G. superciliosus. The most influential variable in the analysis was the eye diameter, significantly larger in the new species than in G. superciliosus. All specimens of the new species that were examined also lacked blue ornamentation on the snout and cheek. At the mitochondrial cytochrome oxidase subunit-I locus, the mean genetic p-distance between the two species was 0.039. With Gymnocranius indicus sp. nov., the genus now includes 12 valid nominal species; three additional species remain undescribed.

ZooBank: urn:lsid:zoobank.org:pub:7E3750AB-D82B-4E36-B591-85C49261C379