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The quaternary material consisting of copper, zinc, tin and sulfur has long attracted the attention of the scientific world in the development of thin layers for photovoltaic applications. In this work, we proposed to make the junction between the absorbent layer consisting of copper-zinc-tin-sulfur Cu 2 ZnSnS 4 (CZTS) and different buffer layers such as zinc sulfide ZnS, tin disulfide SnS 2 , and cadmium sulfide CdS for comparison purposes, in using the simple and low-cost technique of spray pyrolysis at 380 °C for all stages. All the films obtained were characterized by X-ray diffraction (XRD), and UV–visible spectroscopy and the morphology and topography of the layers were assessed under the scanning electron microscope (SEM) and EDXA. Characterization results showed the formation of CZTS thin films whose kesterite structure was improved by annealing at 450 °C under sulfur atmosphere. The grain size also improved from 6.7 to 7.9 nm after annealing. Subsequently, a simulation study by SCAPS-1D is made to assess the efficiency of the photovoltaic cell thus produced. It exhibited the highest power conversion efficiency (PCE) for the cell using SnS 2 as a buffer layer, i.e., 20.25%, compared to 16.14% for the cell using CdS. This confirmed the possibility of favoring SnS 2 in the design of CZTS-based solar cells, suggested in the literature, as a replacement for CdS, and this by the simple technique of spray pyrolysis.

To assess the effect of different whitening toothpastes on enamel surface morphology, chemical profile and their whitening efficiency. Sixty teeth were divided into 5 groups (12 teeth/group); Gp I: brushed with no toothpaste. Gp II: brushed with Pearl-based toothpaste. Gp III: brushed with Charcoal-based toothpaste. Gp IV: brushed with Alumina-based toothpaste. Gp V: brushed with salt and lemon-based toothpaste. Each tooth was brushed with a bean sized toothpaste wetted with distilled water twice daily by using standard electronic toothbrush for four weeks. Enamel surface morphology, chemical profile and color of each tooth were investigated. Chemical profile results and color measurements were analyzed statistically. Gp I revealed normal enamel surface morphology and chemical profile. Gp II and Gp III demonstrated surface morphology close to Gp I with insignificant reduction in mineral content. Gp IV showed obvious shallowing of perikymata ridges, exposure of fish-scale appearance, with pits and depressions, alongside to the significant reduction in mineral content. Gp V presented the most enamel surface alteration with widening of prism sheath and depressions all over the surface, besides the highest significant reduction in mineral content. Gp V, followed by Gp IV, demonstrated the highest color and whiteness changes, followed by Gp III, then Gp II, while the lowest value was in Gp I. Salt & lemon-based toothpaste, followed by Alumina-based, exerted the most considerable changes in the morphology and chemical profile of the enamel surface, beside to the higher whitening effects on teeth than the others.  El objetivo del presente estudio fue evaluar el efecto de diferentes pastas dentales blanqueadoras sobre la morfología y el perfil químico de la superficie del esmalte y su eficacia blanqueadora. Sesenta dientes se dividieron en 5 grupos (12 dientes/grupo); Grupo I: cepillado sin pasta de dientes. Grupo II: cepillado con pasta de dientes a base de perlas. Grupo III: cepillado con pasta de dientes a base de carbón. Grupo IV: cepillado con pasta de dientes a base de Alúmina. Grupo V: cepillado con sal y pasta de dientes a base de limón. Cada diente se cepilló con una pasta de dientes del tamaño de un frijol humedecida con agua destilada dos veces al día utilizando un cepillo de dientes electrónico estándar durante cuatro semanas. Se investigaron la morfología de la superficie del esmalte, el perfil químico y el color de cada diente. Los resultados del perfil químico y las mediciones de color se analizaron estadísticamente. El Grupo I reveló una morfología de la superficie del esmalte y un perfil químico normales. Los Grupos II y III demostraron una morfología de superficie cercana a la del Grupo I con una reducción insignificante en el contenido mineral. El grupo IV mostró una evidente reducción de las crestas perikymatas, exposición de apariencia de escamas de pez, con hoyos y depresiones, junto con una reducción significativa en el contenido mineral. El grupo V presentó la mayor alteración de la superficie del esmalte con ensanchamiento de la vaina del prisma y depresiones en toda la superficie, además de una significativa reducción en el contenido mineral. El grupo V, seguido del grupo IV, demostró los mayores cambios de color y blancura, seguido del grupo III, luego el grupo II, mientras que el valor más bajo se presentó en el grupo I. Las pastas dentales a base de sal y limón, seguidas de las de alúmina, ejercieron los cambios más considerables en la morfología y el perfil químico de la superficie del esmalte, además de tener mayores efectos blanqueadores sobre los dientes que las demás

Illiosentis Van Cleave et Lincicome, 1939 initially included two species: Illiosentis furcatus Van Cleave et Lincicome, 1939 found in the West Atlantic from Cape Cod in Massachusetts, USA to northern Argentina and Illiosentis cetratus Van Cleave, 1945 with restricted distribution in the Pacific coast of southern California. We are reporting I. furcatus from Peru for the first time and describe a population of I. cetratus from the California corbina, Menticirrhus undulatus (Girard), from southern California. The proboscis hook formula was 14 longitudinal rows for I. furcatus of 18-23 hooks each compared to 16 rows of 19-24 hooks each reported by Van Cleave (1945). We complete the inadequate description of I. cetratus with new information on sexual differentiation in the length of the trunk, dorsal vs. ventral hooks, hook roots, trunk spines, two types of anterior recurved rooted hooks vs. posterior rootless straight hooks, measurements of dorsal and ventral hooks and spines, shape of hook roots, terminal position of the female gonopore, and of position of the cephalic ganglion at the anterior margin of the trunk. We also include new details of the reproductive system in both sexes including Saefftigen's pouch and cement gland ducts. We present new SEM and light microscope images. The Energy Dispersive X-ray analysis (EDXA) shows a high level of sulfur in anterior, middle and posterior hooks in various hook sites, as well as spectra of hook tips with a higher relative concentration of sulfur compared to other hook sites. For the placement of I. cetratus, phylogenetic analysis of sequences of three molecular markers, 18S, 28S rRNA and mitochondrial cox 1 genes, was performed with other related available sequences. The resulting analysis illustrated that I. cetratus was nested within a separate clade along with species of two genera, Dentitruncus truttae Sinzar, 1955 and Neotegorhynchus cyprini Lisitsyna, Xi, Orosová, Barčák et Oros, 2022 represented our species of Illiosentis separate from species of Tegorhynchus Van Cleave, 1921 (as also according to the morphology) with which the Illiosentis species were previously synonymised.Illiosentis Van Cleave et Lincicome, 1939 initially included two species: Illiosentis furcatus Van Cleave et Lincicome, 1939 found in the West Atlantic from Cape Cod in Massachusetts, USA to northern Argentina and Illiosentis cetratus Van Cleave, 1945 with restricted distribution in the Pacific coast of southern California. We are reporting I. furcatus from Peru for the first time and describe a population of I. cetratus from the California corbina, Menticirrhus undulatus (Girard), from southern California. The proboscis hook formula was 14 longitudinal rows for I. furcatus of 18-23 hooks each compared to 16 rows of 19-24 hooks each reported by Van Cleave (1945). We complete the inadequate description of I. cetratus with new information on sexual differentiation in the length of the trunk, dorsal vs. ventral hooks, hook roots, trunk spines, two types of anterior recurved rooted hooks vs. posterior rootless straight hooks, measurements of dorsal and ventral hooks and spines, shape of hook roots, terminal position of the female gonopore, and of position of the cephalic ganglion at the anterior margin of the trunk. We also include new details of the reproductive system in both sexes including Saefftigen's pouch and cement gland ducts. We present new SEM and light microscope images. The Energy Dispersive X-ray analysis (EDXA) shows a high level of sulfur in anterior, middle and posterior hooks in various hook sites, as well as spectra of hook tips with a higher relative concentration of sulfur compared to other hook sites. For the placement of I. cetratus, phylogenetic analysis of sequences of three molecular markers, 18S, 28S rRNA and mitochondrial cox 1 genes, was performed with other related available sequences. The resulting analysis illustrated that I. cetratus was nested within a separate clade along with species of two genera, Dentitruncus truttae Sinzar, 1955 and Neotegorhynchus cyprini Lisitsyna, Xi, Orosová, Barčák et Oros, 2022 represented our species of Illiosentis separate from species of Tegorhynchus Van Cleave, 1921 (as also according to the morphology) with which the Illiosentis species were previously synonymised.

Zdzitowiecki, 1984 (Polymorphidae) was described from the intestinal tract of 5 species of seals, including the type and primary host, the Weddell seal (Lesson) in the South Shetlands, West Antarctica. Richardson was the primary paratenic host of 14 fish hosts reported in the original description. We redescribed excysted juveniles from the body cavity of collected off Galindez Island, Argentine Islands, and included its molecular analysis, SEM images, and Energy Dispersive X-ray Analysis (EDXA) for the first time. The identity and distribution of mineral elements in the center and edge of anterior, middle, and posterior proboscis hooks establish their taxonomic relevance. Samples were dehydrated through an ascending ethanol series and then critical point dried, mounted on stubs and coated with carbon with a thickness of 20 nm. The specimens were examined and positioned using the LYRA3 FIB-SEM (TESCAN, Brno – Kohoutovice, Czech Republic), equipped with a Phoenix energy-dispersive X-ray analyzer (Oxford Instruments, Abingdon, England). X-ray spot and live scan analyses were performed at 15 kV with a spot size 2. The AZtec version 4.3 software system (Oxford Instruments, Abingdon, England) was used. We demonstrated the highest calcium levels in all hooks and hook roots compared to sulfur and phosphorus. Here, for the first time, we report a new aspect of the elemental analysis of hooks, demonstrating the differential distribution of sulfur, phosphorous, calcium, and magnesium at the center and margins of anterior, middle, and posterior hooks and hook roots. Calcium was the most prevalent element in roots (root edge and root middle) and the center of middle of all hooks. Phosphorous was equally common but not as prevalent and was highest in the middle of the roots and the middle of all hooks. Sulfur was negligible or absent in the roots and middle of all hooks but highest at hook tips and the edge of the middle hook. The biological and taxonomic importance of this EDXA pattern is discussed, as well as its relevance to hook strength and flexibility, species identity, and comparative systematics. Comparative results were also presented for cystacanths of five other species of acanthocephalans for which EDXA patterns have been studied.

Background Lead (Pb) is a harmful pollutant that disrupts normal functions from the cell to organ levels. Salix babylonica is characterized by high biomass productivity, high transpiration rates, and species specific Pb. Better understanding the accumulating and transporting Pb capability in shoots and roots of S. babylonica , the toxic effects of Pb and the subcellular distribution of Pb is very important. Results Pb exerted inhibitory effects on the roots and shoots growth at all Pb concentrations. According to the results utilizing inductively coupled plasma atomic emission spectrometry (ICP-AES), S. babylonica can be considered as a plant with great phytoextraction potentials as translocation factor (TF) value > 1 is observed in all treatment groups throughout the experiment. The Leadmium™ Green AM dye test results indicated that Pb ions initially entered elongation zone cells and accumulated in this area. Then, ions were gradually accumulated in the meristem zone. After 24 h of Pb exposure, Pb accumulated in the meristem zone. The scanning electron microscopy (SEM) and energy-dispersive X-ray analyses (EDXA) results confirmed the fluorescent probe observations and indicated that Pb was localized to the cell wall and cytoplasm. In transverse sections of the mature zone, Pb levels in the cell wall and cytoplasm of epidermal cells was the lowest compared to cortical and vessel cells, and an increasing trend in Pb content was detected in cortical cells from the epidermis to vascular cylinder. Similar results were shown in the Pb content in the cell wall and cytoplasm of the transverse sections of the meristem. Cell damage in the roots exposed to Pb was detected by propidium iodide (PI) staining, which was in agreement with the findings of Pb absorption in different zones of S. babylonica roots under Pb stress. Conclusion S. babylonica L. is observed as a plant with great potential of Pb-accumulation and Pb-tolerance. The information obtained here of Pb accumulation and localization in S. babylonica roots can furthers our understanding of Pb-induced toxicity and its tolerance mechanisms, which will provide valuable and scientific information to phytoremediation investigations of other woody plants under Pb stress.

Morphological and metrical analyses of monogeneans from the gills of Antarctic rockcod revealed the presence of a new species, sp. n. Fresh specimens of monogeneans collected from from the vicinity of Galindez Island, Argentine Islands, West Antarctica were examined morphologically, by molecular analysis and Energy Dispersive X-ray analysis (EDXA). The new species differs from by the different shapes of anterior and posterior hamuli, the presence of a pronounced sickle-shaped blade of the anterior hamulus and its characteristic wide (wing-like) shaft, serrated on one side, smaller posterior hamulus with a distinct short and broad shaft that widens and is serrated distally, more extensive dimensions of the penis and its pear-like shape, smaller vagina diameter, ovoid egg shape with more pointed anterior pole and blunt posterior pole and long coiled filament as well as different type species of the host in a geographically distant type locality. Genetic data accompanied the description, and phylogenetic analyses inferred that the new species clustered with monogenean species positioned under the family Capsalidae. Molecular data were generated for the 18S and 28S genes of the ribosomal RNA of sp. n. to provide the first molecular analysis for species. EDXA for a species of was offered for the first time.

Acanthocephalus balkanicus Batchvarov et Combes, 1974 was incompletely described from the northern crested newt, Triturus cristatus (Laurenti) (Amphibia: Salamandridae), a possible synonym of the Balkan crested newt, Triturus ivanbureschi Arntzen et Wielstra, from a pond in village of Pesnopoy, southern Bulgaria. We provide a full description of adult males and females of the same taxon from the olm, Proteus anguinus Laurenti (Amphibia: Proteidae), the only exclusively aquatic cave-dwelling vertebrate in Europe, captured in Postojna-Planina Cave System in Slovenia. Cystacanths were also collected from the cave ecomorph of Asellus aquaticus (Linnaeus) (Crustacea: Asellidae) in the same location. Molecular analysis of specimens from Slovenia revealed that they are genetically almost identical to those of Acanthocephalus anguillae (Müller, 1780), a common parasite of European freshwater fishes. We propose to recognise the morphological and host differences by describing A. balkanicus as a new subspecies of A. anguillae. Acanthocephalus anguillae balkanicus is rather small and cylindrical with cylindrical proboscis having 10 rows of 6 hooks with simple roots each, long neck, large balloon-shaped lemnisci, small spherical anterior testis, and 6 club-shaped cement glands in 3 pairs. SEM images reveal more morphological details and the X-ray scans of gallium cut hooks shows considerably higher levels of phosphorus and calcium in adult hooks than in cystacanth hooks, especially in basal areas. Sulfur levels were higher in the arch and basal area of cystacanth hooks than adult hooks. Considering that both definitive and intermediate hosts of the Slovenian population of this acanthocephalan are bound to cave life, it is possible that its entire life cycle is uniquely completed underground.

PurposeImmature Southwellina hispida (Van Cleave, 1925) Witenberg, 1932 from the body cavity of the paratenic host Gillichthys mirabilis Cooper (Gobiidae) in California are described.MethodsNew Scanning Electron images and features of micropores, hook and spine Gallium cut sections and chemistry using Energy Dispersive X-ray analysis (EDXA), and molecular profile are provided for the first time. The 18S rDNA and mt Cox1 sequences were performed for molecular and phylogenetic study.ResultsOur specimens were somewhat comparable to those reported from other paratenic hosts in Asia, Europe, and North and South America but varied in relative sizes of trunk and other structures, proboscis formula, and distribution of trunk spines. About 60 publications were reviewed of which one third included line drawings used for comparative morphometrics. In our specimens, the trunk measured 2.72–3.10 mm long by 0.92–1.07 mm wide and the proboscis 700–800 × 270–312 μm had 20–21 rows of 14–15 hooks each measuring 47–55 long by 12–15 μm wide at base anteriorly, 47–48 × 20–23 μm at middle bulge, and 43–50 × 13–20 μm basally. These measurements, among others were compared with measurements of juveniles from 13 other collections world-wide and intraspecific variability was noted especially in the shape of hook roots that were occasionally misinterpreted. EDXA showed hooks with high levels of Sulfur especially at the tip and edge of all hooks and low levels of Calcium and Phosphorus. Anterior spines had higher levels of Sodium but Gallium cut spine sections had higher levels of Calcium at middle and of Sulfur at base of spines. Micropores were variably distributed on the body wall and extended to the cortical layer of spines. Gene sequences of the 18S and the mitochondrial cytochrome c oxidase subunit 1 (cox 1) region were amplified for specimens of S. hispida. Molecular phylogenetic analysis inference from 18S rDNA and mt Cox1 gene sequences show a close relationship with previously reported myxozoan sequences available on GenBank database. Phylogenetic analysis positioned our S. hispida in a well-supported clade including other members of Polymorphidae.ConclusionThe present study combined morphological, morphometric and molecular data to identify S. hispida.

The morphology of cystacanths and adults of Profilicollis altmani (Perry, 1942) Van Cleave, 1947 (Polymorphidae) were studied from the Pacific mole crab Emerita analoga (Stimpson) (Crustacea, Hippidae) and Belcher’s gull Larus belcheri (Vigors) (Aves, Laridae), respectively, in Peru. Comparative morphometrics with accounts of other populations of P. altmani from elsewhere off the Pacific and Atlantic coasts of North and South America revealed marked intraspecific population variations. We report scanning electron micrographs (SEM) of new features, not before noted or captured in line drawings by earlier observers. We further present microscope images that reveal internal details not previously reported or possible to see with SEM. Energy dispersive X-ray analysis (EDXA) revealed unusual patterns in the chemistry of proboscis hooks especially the high sulfur and diminished phosphorous and calcium in hook tips and low sulfur and high levels of phosphorous and calcium at mid hooks. The size and shape of all hooks of the cystacanths are reported for the first time. Histopathological studies in L. belcheri from Peru are also included. Cystacanths of P. altmani from California were also analyzed for molecular patterns and compared with other sequences reported from other locations. The molecular data and the analysis of our new sequences of cytochrome oxidase I (COI) showed that haplotypes of P. altmani had low genetic variation; the species is not geographically structured, and within its clade no monophyletic group is formed. La morphologie des cystacanthes et des adultes de Profilicollis altmani (Perry, 1942) Van Cleave, 1947 (Polymorphidae) a été étudiée, respectivement, à partir du crustacé Emerita analoga (Stimpson) (Crustacea, Hippidae) et du Goéland Siméon Larus belcheri (Vigors) (Aves, Laridae), au Pérou. La morphométrie comparative avec des données d’autres populations de P. altmani d’autres localités au large des côtes du Pacifique et de l’Atlantique de l’Amérique du Nord et du Sud a révélé des variations intraspécifiques marquées des populations. Nous rapportons des nouvelles observations de microscopie électronique à balayage, non notées auparavant ou non capturées dans des dessins au trait par des observateurs antérieurs. Nous présentons en outre des images au microscope qui révèlent des détails internes qui n’ont pas été signalés auparavant ni possibles à voir avec MET. L’analyse aux rayons X à dispersion d’énergie (EDXA) a révélé des modèles inhabituels dans la chimie des crochets de la trompe, en particulier la teneur élevée en soufre et une diminution du phosphore et du calcium dans les pointes des crochets et des niveaux faibles en soufre et en phosphore et en calcium au milieu des crochets. La taille et la forme de tous les crochets des cystacanthes sont décrites pour la première fois. Des études histopathologiques sur L. belcheri du Pérou sont également incluses. Les cystacanthes de P. altmani de Californie ont également été analysés pour les modèles moléculaires et comparés à d’autres séquences rapportées d’autres endroits. Les données moléculaires et l’analyse de nos nouvelles séquences de cytochrome oxydase I (COI) ont montré que les haplotypes de P. altmani avaient une faible variation génétique. L’espèce n’est pas structurée géographiquement, et au sein de son clade aucun groupe monophylétique n’est formé.

The removal of potentially harmful radioactive waste from the anthroposphere will require disposal in geological repositories, the designs of which often favour the inclusion of a clay backfill or engineered barrier around the waste. Bentonite is often proposed as this engineered barrier and understanding its long-term performance and behaviour is vital in establishing the safety case for its usage. There are many different compositions of bentonite that exist and much research has focussed on the properties and behaviour of both sodium (Na) and calcium (Ca) bentonites. This study focusses on the results of a swelling test on Bulgarian Ca bentonite that showed an unusual gel formation at the expanding front, unobserved in previous tests of this type using the sodium bentonite MX80. The Bulgarian Ca bentonite was able to swell to completely fill an internal void space over the duration of the test, with a thin gel layer present on one end of the sample. The properties of the gel, along with the rest of the bulk sample, have been investigated using ESEM, EXDA and XRD analyses and the formation mechanism has been attributed to the migration of nanoparticulate smectite through a more silica-rich matrix of the bentonite substrate. The migration of smectite clay out of the bulk of the sample has important implications for bentonite erosion where this engineered barrier interacts with flowing groundwater in repository host rocks.