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The chigger species Acomatacarus coahuilensis n. sp. (Acariformes: Trombidiformes: Leeuwenhoekiidae) inhabiting the neck scales of the wary spiny lizard Sceloporus cautus Smith, 1938 (Squamata: Iguania: Phrynosomatidae), from Chihuahuan Desert Province, Coahuila, Mexico, is described herein. The new mite species is assigned to the genus AcomatacarusEwing, 1942, based on a palptarsus with 6 branched setae plus the tarsala (ω). This new species can be separated from the other species in this genus mainly based on the combination of the following characters: presence of mastisetae (MTa) on tarsus III and tibiala (φ) on tibia III, subterminala (ζ1), parasubterminala (z), and pretarsala (ζ2) on tarsus I, 2 genualae (σ1-2) on genu I, onychotriches and claw-like empodium of legs I-III, and absence of mastisetae on tibia III. In addition to the new species, the gastrointestinal nematode Skrjabinoptera phrynosoma (Ortlepp, 1922) Schulz, 1927 (Physalopteridae), was also found, which represents a new host record in the wary spiny lizard. This study reports the third species of the genus Acomatacarus recorded from Mexico and the first record of chigger mites and helminth parasites associated with Sc. cautus.

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Plasterboard is an important building material in the construction industry because it allows for quick installation of walls, partitions, and ceilings. Although a common material, knowledge about its performance related to modern polymers and fabrication conditions is still lacking. The present work analyzes how some manufacturing factors applied during the plaster board fabrication impact on some plasterboard properties, including water absorption, flexural strength, and thermal conductivity. The manufacturing variables evaluated are the dose (D) of polymethylhydrosiloxane (PMHS), the agitation time of the mixture (H), and the drying temperature of the plaster boards after setting (T). The results suggest that factors D, H, and T induce changes in the porosity and the morphological structure of the calcium sulfate dihydrate crystals formed. Performance is evaluated at two levels of each factor following a statistical method of factorial experimental design centered on a cube. Morphological changes in the crystals of the resulting boards were evaluated with scanning electron microscopy (SEM) and the IMAGEJ image analysis program. Porosity changes were evaluated with X-ray microcomputed tomography (XMT) and 3D image analysis tools. The length-to-width ratio of the crystals decreases as it goes from low PMHS dosage to high dosage, favoring a better compaction of the plasterboard under the right stirring time and drying temperature. In contrast, the porosity generated by the incorporation of PMHS increases when going from low-level to high-level conditions and affects the maximum size of the pores being generated, with a maximum value achieved at 0.6% dosage, 40 s, and 140 °C conditions. The presence of an optimal PMHS dosage value that is approximately 0.6-1.0% is evidenced. In fact, when comparing trails without and with PMHS addition, a 10% decrease in thermal conductivity is achieved at high H (60 s) and high T (150 °C) level conditions. Water absorption decreases by more than 90% when PMHS is added, mainly due to the hydrophobic action of the PMHS. Minimum water absorption levels can be obtained at high drying temperatures. Finally, the resistance to flexion is not affected by the addition of PMHS because apparently there are two opposing forces acting: on one hand is the decrease in the length-width ratio giving more compactness, and on the other hand is the generation of pores. The maximum resistance to flexion was found around a dosage of 0.6% PMHS. In conclusion, the results suggest that the addition of PMHS, the correct agitation time of the mixture, and the drying temperature reduce the water absorption and the thermal conductivity of the gypsum boards, with no significant changes in the flexural resistance.

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BACKGROUND: We report large biofilm structures that covered almost the entirety of the lumen and surface of double-J stents in two postrenal transplant patients, with no development of urinary tract infection. Biofilm bacteria of one patient were integrated by coccus in a net structure, whereas overlapping cells of bacilli were present in the other patient. To the best of our knowledge, this is the first time that high-quality images of the architecture of noncrystalline biofilms have been found inside double-J stents from long-term stenting in renal transplant recipients. CASE PRESENTATION: Two renal transplant recipients, a 34-year-old male and a 39-year-old female of Mexican-Mestizo origin, who underwent a first renal transplant and lost it due to allograft failure, had a second transplant. Two months after the surgical procedure, double-J stents were removed and analyzed using scanning electron microscopy (SEM). None of the patients had an antecedent of UTI, and none developed UTI after urinary device removal. There were no reports of injuries, encrustation, or discomfort caused by these devices. CONCLUSION: The bacterial biofilm inside the J stent from long-term stenting in renal transplant recipients was mainly concentrated on unique bacteria. Biofilm structures from the outside and inside of stents do not have crystalline phases. Internal biofilms may represent a high number of bacteria in the double-J stent, in the absence of crystals.

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Among the thecate hydroids brought back by the Proteus-Guyane 2017 expedition of the Muséum national d'histoire naturelle of Paris, France, from French Guiana, two interesting species are reported upon. The plumulariid Callicarpa gracilis Fewkes, 1881, known so far from the type specimen only, is comprehensively redescribed 140 years after its original description. It adopts two different morphotypes with respect to both its tropho- and gonosome, forming either simple or ramified colonies, with either structurally-complex or rudimentary phylactocarps, respectively. Taxonomic notes on the genera Callicarpa Fewkes, 1881 and Hippurella Allman, 1877 are provided in light of their intricate history of origin and fate, together with the provisional resurrection of Antomma Stechow, 1919, as an allied genus of the former. The aglaopheniid Aglaophenia trifida L. Agassiz, 1862, whose gonosome was only partly documented to date, is redescribed thoroughly based on specimens bearing male and female corbulae. Scanning electron microscopy and molecular data were also used to document both species. A checklist of the thecate hydroids from French Guiana gathered during Proteus-Guyane 2017 and Guyane 2014 expeditions is provided as an appendix, together with brief notes on some species. Not dealing with the present study, but taking advantage of it, a new name, Antennella billardi Galea, nom. nov., is proposed as a replacement name for Plumularia balei Billard, 1911, which is a permanently invalid junior primary homonym of P. balei Bartlett, 1907.

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Blueberries are valued for their taste and their high nutritional benefits, including their antioxidant and anti-inflammatory properties. In vitro culturing is an alternative method for clonal propagation, and has been used in many biotechnological studies. Most blueberry research is concentrated on highbush and lowbush taxa (Vaccinium corymbosum and Vaccinium angustifolium respectively), with only limited investigations of rabbiteye cultivars (Vaccinium virgatum) that are more suitable for subtropical climates and regions with warmer winters as a result of climate change. There is therefore a need to determine in vitro protocols for that species and group of cultivars. We examined here adventitious shoot regeneration in the 'Delite' rabbiteye blueberry cultivar. Leaf explants were cultured in vitro in Woody Plant Medium (WPM), and the effects of different thidiazuron (TDZ) concentrations, the orientation of the leaf (adaxial or abaxial surface in contact with the medium), and two portions of the leaf segment (basal or apical) were examined. De novo shoot development was studied using light and scanning electron microscopy. All concentrations of TDZ used showed similar survival and regeneration rates; 0.5 µM TDZ showed high efficiency in regenerating adventitious shoots (100%, with 57 adventitious shoots/explant), as did the adaxial surface in contact with the medium using either the apical or the basal portion of the leaf (97% shoot regeneration, 47.5 adventitious shoots/explant). Anatomical analyses showed direct and indirect organogenesis. The shoots developed leaf primordia with stomata, trichomes, and well-developed vascular tissues, with further elongation and rooting of the plants. We therefore describe here a high-efficiency regeneration method through de novo shoot organogenesis using TDZ in foliar explants of rabbiteye blueberry, with direct and indirect organogenesis.

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Rubber dandelion (Taraxacum kok-saghyz Rodin; TK) has received attention for its natural rubber content as a strategic biomaterial, and a promising, sustainable, and renewable alternative to synthetic rubber from fossil carbon sources. Extensive research on the domestication and rubber content of TK has demonstrated TK's potential in industrial applications as a relevant natural rubber and latex-producing alternative crop. However, many aspects of its biology have been neglected in published studies. For example, floral development is still poorly characterized. TK inflorescences were studied by scanning electron microscopy. Nine stages of early inflorescence development are proposed, and floral micromorphology is detailed. Individual flower primordia development starts at the periphery and proceeds centripetally in the newly-formed inflorescence meristem. Floral organogenesis begins in the outermost flowers of the capitulum, with corolla ring and androecium formation. Following, pappus primordium-forming a ring around the base of the corolla tube-and gynoecium are observed. The transition from vegetative to inflorescence meristem was observed 21 days after germination. This description of inflorescence and flower development in TK sheds light on the complex process of flowering, pollination, and reproduction. This study will be useful for genetics, breeding, systematics, and development of agronomical practices for this new rubber-producing crop.

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AIM: To evaluate the morphology and impact of root canal preparation in maxillary incisors with palatogingival grooves (PGG). METHODOLOGY: Twenty extracted human maxillary incisors with PGG were subjected to macroscopic analysis and scanning electron microscopy analysis (SEM). The following characteristics of the PGG were evaluated: depth, point of origin in the cingulum, extension and position on the lingual surface. Furthermore, the presence of calculus, communications between the root canal system and the PGG, and root resorptions were investigated. The root canals were subsequently instrumented with K-files of three consecutive sizes. The teeth were sectioned, and the axial plane of each tooth section was imaged using SEM before and after instrumentation. The distance between the root canal walls and the PGG was calculated according to the location. Additionally, the distance between canal walls and cementum was measured at three different sites, to verify if instrumentation influenced dentine removal on a specific wall in teeth with PGG. Statistical analysis was performed using the Mann-Whitney or Student's t-test (P < 0.05). RESULTS: Macroscopic analysis revealed that a deep groove was most frequently observed (75%), followed by a depression/shallow groove (25%) (P < 0.05). PGG typically originated in the distal margin ridge of the cingulum (65%) (P < 0.05), extending only to the middle (45%) or up to the apical (50%) third of the root (P < 0.05). Additionally, PGGs were typically located on the distal aspect of the lingual surface (70%) (P < 0.05). Calculus was concentrated on the surface of the crown and cementum-enamel junction (P < 0.05). Communication between the root canal and PGG was present in 35% of teeth, and root resorptions were noted in 50% of teeth. The distance between the external root surface and the pulp cavity was significantly narrower after instrumentation (P < 0.05); however, root canal preparation did not influence dentine removal on the specific wall associated with the groove (P > 0.05). CONCLUSIONS: Palatogingival grooves were characteristically deep and originated from the distal margin of the cingulum. Although it has been associated with a thinner root wall, root canal preparation did not influence the thickness of the specific wall in the maxillary incisors with PGG.

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A ordem Coronatae é considerada o grupo basal de Scyphozoa, contendo aproximadamente 60 espécies. Observar do ciclo de vida é fundamental para desvendar a sistemática e a taxonomia da ordem. Entretanto, estudos recentes relacionados apenas ao estágio de pólipo foram capazes de promover progresso usando, exclusivamente, caracteres morfológicos do tubo peridérmico. A falta de conhecimento sobre o número real de espécies de coronados ocorrentes no Brasil e sua distribuição ao longo da fauna costeira é um fator que limita abordagens mais avançadas para interpretar a biogeografia desses animais. Nosso objetivo foi identificar e descrever esses pólipos do Norte, Sudeste e Sul do Brasil, levando em consideração a distribuição batimétrica e longitudinal das espécies. As medidas do tubo peridérmico obtidas por meio de microscopia de luz e a organização e morfologia dos espinhos internos, observadas por meio de microscopia eletrônica de varredura, permitiram o reconhecimento de 3 morfotipos, identificados apenas ao nível de gênero: dois morfotipos de Nausithoe (oito e 16 espinhos) e um de Atorella.(AU)

Members of the order Coronatae are considered the basal group of Scyphozoa, containing approximately 60 species. Observation of life cycle is critical to unravel the systematics and taxonomy of the order. However, recent studies related only to the polyp stage were able to promote progress using solely morphological characters of the periderm tube. The lack of knowledge about the actual number of coronate species occurring in Brazil and their distribution along the coast is a factor that limits more advanced approaches to interpret the biogeography of these animals. Our goal was to identify and describe the Coronatae polyps from N, SE and S Brazil, taking into account the bathymetric and longitudinal distribution of species. Measurements of the periderm tube under light microscopy and the organization and morphology of the internal cusps observed through Scanning Electron Microscopy allowed the recognition of three morphotypes, recognized only at the genus level: two morphotypes of Nausithoe (eight and 16 cusps) and one form of Atorella.(AU)

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A ordem Coronatae é considerada o grupo basal de Scyphozoa, contendo aproximadamente 60 espécies. Observar do ciclo de vida é fundamental para desvendar a sistemática e a taxonomia da ordem. Entretanto, estudos recentes relacionados apenas ao estágio de pólipo foram capazes de promover progresso usando, exclusivamente, caracteres morfológicos do tubo peridérmico. A falta de conhecimento sobre o número real de espécies de coronados ocorrentes no Brasil e sua distribuição ao longo da fauna costeira é um fator que limita abordagens mais avançadas para interpretar a biogeografia desses animais. Nosso objetivo foi identificar e descrever esses pólipos do Norte, Sudeste e Sul do Brasil, levando em consideração a distribuição batimétrica e longitudinal das espécies. As medidas do tubo peridérmico obtidas por meio de microscopia de luz e a organização e morfologia dos espinhos internos, observadas por meio de microscopia eletrônica de varredura, permitiram o reconhecimento de 3 morfotipos, identificados apenas ao nível de gênero: dois morfotipos de Nausithoe (oito e 16 espinhos) e um de Atorella.

Members of the order Coronatae are considered the basal group of Scyphozoa, containing approximately 60 species. Observation of life cycle is critical to unravel the systematics and taxonomy of the order. However, recent studies related only to the polyp stage were able to promote progress using solely morphological characters of the periderm tube. The lack of knowledge about the actual number of coronate species occurring in Brazil and their distribution along the coast is a factor that limits more advanced approaches to interpret the biogeography of these animals. Our goal was to identify and describe the Coronatae polyps from N, SE and S Brazil, taking into account the bathymetric and longitudinal distribution of species. Measurements of the periderm tube under light microscopy and the organization and morphology of the internal cusps observed through Scanning Electron Microscopy allowed the recognition of three morphotypes, recognized only at the genus level: two morphotypes of Nausithoe (eight and 16 cusps) and one form of Atorella.

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Banana is the second largest export crop in Colombia. To meet the demand of international markets, high amounts of chemical fertilizers are required, which represent high costs and can be hazardous to the environment. Plant growth promoting rhizobacteria (PGPR) can, at least partially, replace chemical fertilizers. In this paper, we evaluated the effect of nine PGPR of the genera Bacillus and Pseudomonas on banana growth. Banana seedlings were produced through tissue culture and acclimatized in the greenhouse core. Plants were inoculated with the rhizobacteria and growth parameters (plant height, leaf number, leaf area, pseudostem thickness, root and shoot fresh weight, root and shoot dry weight) were assessed after 55 days. The two best performing PGPR, Bs006 and Ps006 previously identified as Bacillus amyloliquefaciens and Pseudomonas fluorescens, respectively, promoted banana growth similarly or even slightly superior to 100% chemical fertilization, and were selected for further characterization of root colonization by both eletron microscopy and confocal microscopy of fluorescence in situ hybridization (FISH)-stained root tissues. Both P. fluorescens Ps006 and B. amyloquifaciens Bs006 showed ability to colonize banana roots, but Bs006 appeared faster than Ps006 in the colonization dynamics. This work demonstrated that inoculation of rhizobacteria Bacillus amyloliquefaciens Bs006 and Pseudomonas fluorescens Ps006 could partially replace the chemical fertilization of tissue cultured banana plants, and therefore could be used for the formulation of a new biofertilizer.

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Biocompatible membranes are widely used in medicine to stimulate bone repair. Several studies have demonstrated that laser photobiomodulation (PBM) also stimulates osteoblast proliferation and osteogenesis at the fracture site, leading to a greater deposition of bone mass and accelerating the process of bone consolidation. This work assessed the therapeutic effect of 780-nm laser PBM and a polystyrene membrane coated with norbixin and collagen (PSNC) on bone healing in rats with calvarial bone defect. Histological staining, Raman spectroscopy, and scanning electron microscopy (SEM) were used to evaluate the bone repair process. Four experimental treatment groups were compared: C, control; M, membrane only; L, laser PBM only; and ML, membrane + laser PBM. A bone defect was created in the calvaria of each animal, with each group subdivided into two subgroups that underwent euthanasia after 15 and 30 days treatment. The L and ML groups were irradiated (λ = 780 nm, ED = 6 J/cm2, P = 60 mW, t = 4 s) postoperatively on alternate days until they were euthanized. The bone concentration of hydroxyapatite (CHA) showed a clear gradation with increasing phosphate area in the order B (normal cortical bone) > L > M > ML > C for both periods. The PSNC membrane was effective in reducing the inflammatory process and served as a scaffold for bone repair. The laser PBM also showed positive effects on the bone repair process with increased deposition and organization of the newly formed bone. However, laser PBM failed to improve the bioactive properties of the membrane scaffold.

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Phototherapy using coherent light (lasers) and non-coherent light (light-emitting diodes (LEDs)) has been investigated for the purpose of biomodulation in biological tissues. Several effects can be expected, including pain moderation, biostimulation of cellular tropism, anti-inflammatory effects, regular circulatory stimulation, and tissue repair. The aim of this study was to evaluate the effect of LED (λ945 ± 20 nm, 48 mW) therapy on the regeneration process in femoral lesions of rats (Wistar). Seven irradiation sessions were held, with a 48-h interval between sessions. The animals were euthanised 14, 21, and 28 days after surgery. Bone samples were analysed by histomorphometry, micro X-ray fluorescence spectroscopy, scanning electron microscopy, and optical densitometry. The results demonstrated the effective positive influence of low-intensity LED therapy using the near-infrared region on the tissue repair process in diabetic animals, especially in the early stages of repair (14 and 21 days after surgery). It can be concluded that LED therapy positively influences bone formation in the early stages of the bone repair process in non-diabetic and diabetic animals, without causing changes in the optical density and volume of tissue in the final stages. No influence of LED therapy was observed on the percentage of calcium, percentage of phosphorus, Ca/P ratio, or optical mineral density in non-diabetic animals. However, increased mineral concentration was evident in the diabetic animals treated with the LED during the repair process.

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AIM: To determinate the significance of risk factors with the presence of biofilm on catheters of patients attended at tertiary hospital cares. MATERIAL AND METHODS: A total of 126 patients were included, data collection by observing the handling of the CVC, clinical history and microbiological isolation methods of CVCs tips (Roll-plate, sonication and scanning electron microscopy) were evaluated. RESULTS: Certain factors, such as the lack of proper hand washing, the use of primary barriers and preparing medications in the same hospital service, showed an important relationship between biofilm formation in CVCs. The sonication method presented that most of the samples had isolation of multispecies 29 samples (64%); in contrast with the roll-plate method, just one sample (3%) was isolated. CONCLUSIONS: The importance of the strict aseptic techniques of insertion and of the handlings of CVC was highlighted, the failure of both techniques was related to the biofilm formation and was evidenced using the scanning electron microscopy. Since this tool is not available in most hospitals, we present the correlation of those evidences with other standard microbiological methods and risk factors, which are necessary for the sensible detection of the different steps of the biofilm formation on CVC and their correct interpretation with clinical evidences.

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The genus Desmodium is represented in Santa Catarina State, Brazil, by 13 species, all with lomentaceous fruits. Shape, size and isthmus margin of loments vary, while the surface is glabrous, or covered by trichomes of different types. Morphological diversity of trichomes becomes particularly relevant to taxonomic description. The trichome types present on the surface of Desmodium fruits provide data for the identification and classification of species in the State. To assess this, three fruits of each species were collected and deposited at two herbaria, HBR and FLOR, in Santa Catarina, Brazil. Some rehydrated samples were examined using light microscopy (LM); and some sections were exposed to the following histochemical reagents: Sudan III for oils and Thionine for mucilage. The structural aspects of trichomes can be classified into uni- or multicel- lular and may still be simple, i.e., nonglandular or glandular. Using scanning electron microscopy (SEM), five types of trichomes were identified and analyzed among the Desmodium species studied: uncinate, uniseriate, globose multicellular, globose unicellular and subulate. Characteristics, such as loment margin and article form, glabrescent or pillous indument, trichome type, with or without papillous epidermal cells and epicuticular striations, showed relevant diagnostic value. An identification key was developed for Desmodium species from Santa Catarina State, Brazil, based on macro and micromorphological characters of the fruit.

Características morfológicas y micromorfológicos de frutos Desmodium (Leguminosae: Papilionoideae). El género Desmodium está representado en Santa Catarina, Brasil, por 13 especies, todas con frutos lomentaceos. Los lomentos han tenido variación en forma, tamaño y características del margen del istmo, y la superficie es glabra o cubierta por tricomas de diferentes tipos. La diversidad morfológica de los tricomas se vuelve particularmente relevante para la descripción taxonómica. Los tipos de tri- comas presentes en la superficie de los frutos Desmodium, proporcionan datos para la identificación y clasificación de las especies en el Estado de Santa Catarina, Brasil. Tres frutos de cada especie fueron recogidos y depositados en el Herbario (HBR y FLOR, Santa Catarina, Brasil). Algu- nas muestras fueron rehidratadas y examinadas usando microscopía de luz (LM), las secciones fueron expuestas a los siguientes reactivos histoquímicos: Sudan III para los aceites y Tionina para mucílago. Los aspectos estructurales de los tricomas se pueden clasificar en uni o multicelulares y pueden todavía ser simples, es decir, no glandular o glandular. Por medio del uso de la microscopía elec- trónica de barrido (SEM), cinco tipos de tricomas se han identificado y analizado entre las especies de Desmodium estudiadas: uncinado, uniseriado, globoso multicelular, globoso unicelular y subulado. Características como el margen del lomento y la forma del artículo, indumento glabrescente o piloso, tipo de tricomas con o sin células epidérmicas papilosas, y estrías epicuticulares mostraron valor de diagnóstico relevante. La clave de identificación fue desarrollada para especies de Desmodium del Estado de Santa Catarina, Brasil, basado en caracteres macro y micromorfológicos del fruto.

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The correlative light-electron fractography technique combines correlative microscopy concepts to the extended depth-from-focus reconstruction method, associating the reliable topographic information of 3-D maps from light microscopy ordered Z-stacks to the finest lateral resolution and large focus depth from scanning electron microscopy. Fatigue striations spacing analysis can be precisely measured, by correcting the mean surface tilting with the knowledge of local elevation data from elevation maps. This new technique aims to improve the accuracy of quantitative fractography in fatigue fracture investigations.

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The surface morphology of the ctenidia of Spondylus spinosus Schreibers, 1793 was studied with light and scanning electron microscopy for comparison with the gill structures of other bivalves. The demibranch of S. spinosus is heterorhabdic, with the principal filaments at the descending lamellae and ordinary filaments at the ascending lamellae. The gill lamellae have a prominent gauze-like structure at their distal part, with numerous groups of eight ordinary filaments. They bear ciliary arrays on their frontal surfaces and ostia at their latero-frontal surfaces. Frequent cirral plates form regular interfilamentary junctions. The description of the gill structure of S. spinosus presented here can be used to derive implications for the correlations among the structure, habitat and mode of life of this species. At a particular stage of its adult life, Spondylus spinosus could be used as a subject for biomonitoring studies in natural and experimental environments.(AU)

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The surface morphology of the ctenidia of Spondylus spinosus Schreibers, 1793 was studied with light and scanning electron microscopy for comparison with the gill structures of other bivalves. The demibranch of S. spinosus is heterorhabdic, with the principal filaments at the descending lamellae and ordinary filaments at the ascending lamellae. The gill lamellae have a prominent gauze-like structure at their distal part, with numerous groups of eight ordinary filaments. They bear ciliary arrays on their frontal surfaces and ostia at their latero-frontal surfaces. Frequent cirral plates form regular interfilamentary junctions. The description of the gill structure of S. spinosus presented here can be used to derive implications for the correlations among the structure, habitat and mode of life of this species. At a particular stage of its adult life, Spondylus spinosus could be used as a subject for biomonitoring studies in natural and experimental environments.

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The surface morphology of the ctenidia of Spondylus spinosus Schreibers, 1793 was studied with light and scanning electron microscopy for comparison with the gill structures of other bivalves. The demibranch of S. spinosus is heterorhabdic, with the principal filaments at the descending lamellae and ordinary filaments at the ascending lamellae. The gill lamellae have a prominent gauze-like structure at their distal part, with numerous groups of eight ordinary filaments. They bear ciliary arrays on their frontal surfaces and ostia at their latero-frontal surfaces. Frequent cirral plates form regular interfilamentary junctions. The description of the gill structure of S. spinosus presented here can be used to derive implications for the correlations among the structure, habitat and mode of life of this species. At a particular stage of its adult life, Spondylus spinosus could be used as a subject for biomonitoring studies in natural and experimental environments.

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Introducción: el objetivo fue describir los cambios físico-químicos que ocurren en los tejidos y materiales dentales empleados en un tratamiento endodóncico convencional, al ser sometidos a altas temperaturas, a través de microscopía electrónica de barrido (MEB). Métodos: in vitro, se sometieron dos dientes premolares humanos a 200 y 400 ºC respectivamente, con el fin de estandarizar una técnica para la observación de los cambios físicos y químicos en los tejidos dentales (esmalte y dentina) y de los materiales de uso odontológico empleados comúnmente en endodoncia (gutapercha y cemento endodóncico a base de resina epóxica). Resultados: tanto los tejidos como los materiales dentales observados en este estudio piloto, presentaron gran resistencia a las altas temperaturas sin variar considerablemente su macroestructura, de tal manera que los cambios físicos (estabilidad dimensional, fisuras, grietas, fracturas, textura, carbonización) y químicos (elementos químicos constituyentes) pueden llegar a ser identificables y asociarse a cada rango de temperatura específico através del análisis MEB y espectrofotométrico. Conclusiones: los tejidos y los materiales dentales presentan gran resistencia a la acciónde altas temperaturas sin alterar su macroestructura de forma significativa. Del mismo modo, presentan cambios físicos y químicos que pueden contribuir con el proceso de identificación de un cadáver o restos humanos quemados, incinerados o carbonizados.

Introduction: the objective of this study was to describe the physicochemical changes occurring in dental tissues andmaterials used in a conventional endodontic treatment when subjected to high temperatures, by means of scanning electron microscopy(SEM) Methods: in vitro, two human premolar teeth were subjected to temperatures of 200°C and 400°C respectively, with the purpose ofstandardizing a technique for the observation of physical and chemical changes in dental tissues (enamel and dentin) and dental materialscommonly used in endodontic treatment (root canal gutta-percha and epoxy resin-based endodontic cement). Results: both the tissues and the dental materials analyzed in this pilot study presented great resistance to high temperatures without significantly changing their macrostructure; therefore, the physical changes (dimensional stability, cracks, crevices, fractures, texture, carbonization) and the chemical ones (constituent chemical elements) may turn out to be identifiable and associated with each specific temperature range by means of SEM and spectrophotometric analysis. Conclusions: dental tissues and materials display great resistance to the action of high temperatures, without significantly altering their macrostructure. Similarly, they experience physical and chemical changes that may contribute to theprocess of identification of a corpse or human remains that have been burned, incinerated or charred.

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Antibacterial properties and chemical characterization of the essential oils from summer savory (Satureja hortensis) extracted by microwave-assisted hydrodistillation (MAHD) were compared with those of the essential oils extracted using the traditional hydrodistillation (HD) method. While MAHD at 660 W required half as much time as HD needed, similar antibacterial efficacies were found from the essential oils obtained by the two extraction methods on two food pathogens (Staphylococcus aureus, a gram positive bacterium, and Escherchia coli, a gram negative bacterium). Also, as it was the case with the essential oils extracted by HD, that of MAHD indicated greater influence on S. aureus than on E. coli. The compositions of the extracted essential oils were also studied using GC-MS analysis. The same components with negligible differences in their quantities were found in the extracted essential oils using the two methods outlined above. Overall, to reduce the extraction time, MAHD can be applied at higher microwave levels without any compromise in the antibacterial properties of the essential oils extracted.

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