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A historical outline is provided about the pictorial representation of exochorions within Lepidoptera, in selected scientific treatises by prelinnean authors (Aldrovandi, Moffet, Hooke, Malphigi, Merian, Swammerdam, Harris, and Scudder), between 1602 and 1889. Subsequently, a selection of direct precedents in the research line of Llorente-Bousquets and cols. is referred to and commented upon, organized by their associated styles of production (chirography, photography and scanning electron microscope SEM), in order to compare and discuss their respective contributions to exochorionic studies of Papilionoidea (Insecta: Lepidoptera). The D&G+ model of epistemic virtues is revisited as a demarcation criterion for scientific images, to which two components are added: Natural-Objective Mode (MON) and Collaborative Principle of Representational Division of Labor (PCDTR). PCDTR is proposed as a general axiological meta-criterion in the epistemological analysis and evaluation of scientific images. [ABSTRACT FROM AUTHOR]

An epistemological framework is given to evaluate the scientificity of Llorente-Bousquets and collaborators' exochorionic images, understood as schematic representations of a system of morphological characters. The images are evaluated at the intersection of three units of analysis: styles, dimensions and epistemic virtues. They are analyzed according to: i) three styles: chirography, photography, and scanning electron microscope (SEM); ii) four virtues: Truth-to-Nature (TtN), Mechanical Objectivity (MO), Structural Objectivity (SO), and Trained Judgment (TJ). Two substyles of chirography are located: descriptive-realistic and 'lettered schema'. The schema is interpreted as characteristica universalis, conceptography or direct representation of morphological concepts, of which provides a priori knowledge. The scientific nature of the image production process is analyzed and evaluated through the model of epistemic virtues and a proposed extended version of it (D&G+). [ABSTRACT FROM AUTHOR]

The fig is a climacteric fruit with great perishability and short postharvest life. It has an ostiole that serves as a pollination medium and an entry site for fungal pathogens. In this work, three different protection strategies and their effect on the development of the ostiole were evaluated in addition to the presence of fungi. Fifteen white fig plants of the "Guarinta" variety were used. Images wereobtained by scanning electron microscope. The ostioli were evaluated in their structure and diameter. The presence of microorganisms was performed simultaneously. The mean diameter (mm) of pore in the control 'C' was 7.64, in protection with mesh 'M' it was 5.36 and protection with aluminum foil 'PA', 0.98; showing significant differences between the PA and C treatments. Figs wrapped with PA showed a higher incidence of pathogenic fungi. This constitutes a first approximation in the evaluation of types of protection. [ABSTRACT FROM AUTHOR]

This text shows the impact of the Wari Empire on the way of life of the local population at the coastal site of Ancon, through the analysis of non-specific bone stress, as well as the traceology of the manufacturing techniques of malacological and lapidary funerary objects. The research on 11 individuals from the Necropolis of Miramar corresponding to the end of the Middle Horizon (800-1100 AD) is presented and the characterization of 72 malacological and lapidary pieces with scanning electron microscope and experimental archaeology. The result of the bone analysis shows that the greatest vulnerability occurred in children under two years old and young male adults, while the neonates and infants having the greatest amount and variety of stone materials from different regions of the Central Andes and mollusks from tropical waters. Despite the diversity of origins, the craft production of these objects was homogeneous and standardized as a result of a local production, while the elites at Ancon had benefited from the acquisition and distribution of this items. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop ceramic tiles that comply with the Colombian Technical Standard - NTC 919, using agro-industrial banana residues as a feldspar substitute. To this end, test tiles were designed with various mixtures in flours and ashes from the agro-industrial residue and others with the conventional ceramic formula, called PATRON sample. In all the mixtures, the physical-ceramic properties and density were determined. The alternative mixture that showed the best results continued to be analyzed with X-Ray Fluorescence, X-Ray Diffraction and Scanning Electron Microscope. The physical-ceramic properties showed a better suitability in the test tiles prepared with 5% banana peel flour. XRF analyses show a predominance of silica and aluminium, which probably associated with mullite, according to XRD; this was also observed in the microscopic images. The results of the analyses reveal a product with a quality within the NTC 919 standard. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop ceramic tiles that comply with the Colombian Technical Standard - NTC 919, using agro-industrial banana residues as a feldspar substitute. To this end, test tiles were designed with various mixtures in flours and ashes from the agro-industrial residue and others with the conventional ceramic formula, called PATRON sample. In all the mixtures, the physical-ceramic properties and density were determined. The alternative mixture that showed the best results continued to be analyzed with X-Ray Fluorescence, X-Ray Diffraction and Scanning Electron Microscope. The physical-ceramic properties showed a better suitability in the test tiles prepared with 5% banana peel flour. XRF analyses show a predominance of silica and aluminium, which probably associated with mullite, according to XRD; this was also observed in the microscopic images. The results of the analyses reveal a product with a quality within the NTC 919 standard. [ABSTRACT FROM AUTHOR]

Copyright of Momento: Revista de Física is the property of Universidad Nacional de Colombia, Departamento de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The anticorrosive behaviour of the electrogalvanized carbon steel with PZn, PZn- Ca and PZnNi phosphate layers additionally coated with the conversion layers of cerium oxide in chloride-contaminated media has been studied. The composition and structure of investigated samples were characterized by scanning electron microscope SEM, while the corrosion behaviour was investigated applying voltammetric and electrochemical impedance spectroscopy EIS measurements. The data obtained have shown that all investigated samples additionally coated with cerium oxide conversion coatings exhibited better protective abilities. To summarize the results of electrochemical and SEM measurements it was stated that the most porous (F = ~1-2%) PZnNi/Ce coating exhibited the best protective abilities in a chloride-contaminated solution. Therefore, cerium ions are able to penetrate into the substrate, which is zinc coated steel, through the open pores of the PZnNi layer. [ABSTRACT FROM AUTHOR]

Background and aims: Urvillea Kunth is a small American genus of climbing shrubs or subshrubs, rarely erect subshrubs or rhizomatous hemicryptophytes. It is distributed from the southwestern United States to central Argentina, being Brazil the main center of diversity. Urvillea is characterized by its duodicogamy, trifoliated leaves and zygomorphic flowers; usually five sepals, four nectariferous lobes, anthers with a more or less conspicuous apical connective extension, and subchartaceous or chartaceous capsular fruits. Although some regional treatments are available, the only published comprehensive treatment of the genus was done by Radlkofer in 1932. The current work is the most up to date taxonomic revision of Urvillea based on modern collections and biosystematic studies. M&M: Taxonomic data were gathered from the literature, including phylogenetic studies, and from field observations, where specimens from 90 herbaria were analyzed. Morpho-anatomical observations were made with stereoscopic, optical and scanning electron microscope. Results: In this revision, 20 species of Urvillea are recognized. Most species have a wider geographical distribution than previously recognized. Nine names (eight at the species level and one form) are here lectotypified; in addition, four new synonyms are proposed. Furthermore, descriptions of pollen morphology are provided for all species. [ABSTRACT FROM AUTHOR]

Thin films of Zinc Oxide (ZnO) were grown on glass substrates conductive FTO (Fluorine-doped tin oxide) with a thickness of 400 nm. The hybrid films of ZnO and dye (N719) were grown on FTO conductive glass to a thickness of 600 nm. The growth of hybrid films of ZnO / N719 was made by two steps, cathodic electrodeposition and diping. The effect of increasing the temperature for growth of the hybrid films to 80 °C allows absorption of the dye in the fixed structure of ZnO, completely modifying the ZnO structure of hexagonal wirtzita to be evaluated using the Scanning Electron Microscope (SEM) and X-ray diffraction (XRD). Morphological response study by Scanning Electron Microscope (SEM) showed that it is possible to obtain pores with a diameter <350 nm in the structure of ZnO completely changing its hexagonal shape. The response of optical properties in the hybrid ZnO films / N719, proved to be found two peaks of absorption in the spectrum, 340 nm and 660 nm when a metal-X adheres to the structure of ZnO. [ABSTRACT FROM AUTHOR]

Failure mechanisms in structural materials have been under investigation for several years. Nowadays, the implementation of sophisticated in situ electron microscopy tests is providing new insights in several fields of chemistry, physics, and materials science by allowing direct observation of a wide variety of phenomena at submicron and even atomic scale. These experiments may involve controlled temperature and atmosphere, mechanical loading, magnetic and/or electric field among other conditions that are imposed to the sample while its response or evolution is registered. A novel in situ high temperature-strain test into a Scanning Electron Microscope (SEM) makes possible the real-time observation of phenomena with resolution of 5 μm, providing qualitative and quantitative data. This setup was used to study the Grain Boundary Sliding (GBS) mechanism and its effect on the high temperature cracking phenomenon known as Ductility-Dip Cracking (DDC). This methodology was applied to study the mechanical behavior of Ni-base filler metal alloys ERNiCrFe-7 and ERNiCr-3, which were evaluated between 700 and 1000 ºC. The DDC susceptibility (threshold strain, εmin) for both alloys was quantified. The εmin of ERNiCrFe-7 and ERNiCr-3 alloys was 7.5 % and 16.5 %, respectively, confirming the better resistance of ERNiCr-3 to DDC. [ABSTRACT FROM AUTHOR]

Alq3 (tris (8-hydroxyquinolate) aluminum) thin films were deposited on glass by thermal evaporation in order to establish the optimal evaporation rates of thin films deposited between 30 to 120nm on a substrate with temperatures between 60 and 120°C. The thin films were characterized by SEM microscopy and perfilometry to compare the obtained thickness in-situ by quartz crystals; furthermore photoluminescence measures were made. [ABSTRACT FROM AUTHOR]

In this work are presented results in the study of photoconductivity of ZnSe thin films deposited on glass substrate. The effect of substrate temperature on the spectral photoconductivity and morphological properties of ZnSe thin films were studied. The Spectral response appeared between 290 and 500 nm. In the spectral responses were found two contributions associated with transitions labelled E (Γ7V∪ Γ6C y Eg(Γ8V∪ Γ6C, with energy values of 3:35 and 2:80 eV, respectively. The response time of the sample is associated with the morphology of the samples. In the samples prepared at lower temperatures were obtained response times on the order of seconds, whereas the time decreases by one magnitude order in the samples prepared at the substrate temperature of 250 °C. [ABSTRACT FROM AUTHOR]

X-Ray Diffraction, Scanning Electron Microscopy, High Resolution Transmission Electron Microscopy studies have been made of TlInS2 layered semiconductor compound to clarify its crystal structure, which has remained ambiguous through several decades. Similarly, in recent studies it has been reported at ambient conditions this semiconductor can crystallize in several polytypes with monoclinic structure, which may be present in the same sample. In this study it was found at ambient temperature TlInS2 crystallized in a monoclinic structure, space group C2/c with lattice parameters a = 8.609 Å, b = 14.904 Å, c = 9.471 Å, ß = 110.44 °, it was not found the presence of more than one polytype in the studied sample. Additionally, the results obtained were compared with other previously derived using an analysis of the vibration modes of the compound by means of Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Through a combination of SEM-EDS technique could study a fragment of tattooed and non tattooed skin of the Lady of Cao, a woman of high social class Moche (Mochica early). EDS probe applied to the area with tattoo indicates the use of ferrous oxide (FeO). According to the information and finding archaeobotany tattooed mummies are holding fruits of "Jagua" Genipa americana L., is possible that this fruit of wild origin have served as raw material for use in tattooing the Lady of Cao. [ABSTRACT FROM AUTHOR]

A new species, Scutellaria hsiehii (Lamiaceae), was collected from central part of the island. Scutellaria hsiehii is close to S. playfairii Kudo, but can be distinguished by its slender procumbent stems, long petiole, long ovate leaves with 3-5 serration along the margin and nutlet coat with short grapping-hook tubercles. A taxonomic description, line drawing, pollen morphology in SEM observation, distribution information, and color photographs of the floral characters are provided. [ABSTRACT FROM AUTHOR]

The genus Notofenusa was first described in 1959 from Argentina and Chile. Subsequently, in 1973 the presence of Notofenusa surosa in the Nothofagus forest is confirmed. The aim of this note is to provide information about the features that allow its identification and the ecological aspects related to its habit as a leaf miner insect. The identification of these specimens was performed through taxonomic keys with the support of scanning electron microscope photographs. [ABSTRACT FROM AUTHOR]

This article describes the structural characterization of the husk of modified rice through the process of advanced oxidation with the reagent Fenton; the transformation was carried out with the intention of increasing the number of active sites on the material's surface, and consequently to generate an absorbent with a greater capacity for the removal of Cr (VI) ions in solution, compared to the husk of natural rice. The characterization of modified material was determined through distinct experimental techniques that include the analysis of the functional groups present on the absorbent's surface through infrared spectroscopy with diffuse reflectance, (DRIFT), likewise, a surface morphology analysis of the husk through a scanning electron microscope (SEM), a compositional analysis and thermogavimetric (TGA). All of these tests were carried out before and after the modification process. The results of the DRIFT point towards a slight shift and attenuation in the vibration frequencies of the functional groups implicated in the structural modification, whereas the SEM analysis indicated noticeable changes in the morphology of the absorbent material. Meanwhile, the compositional analysis showed considerable changes in the percentage of the material components, whose presence was confirmed through the TGA analysis, after decomposing at the expected temperatures. In short, all results confirm the structural modification of the absorbent tested. [ABSTRACT FROM AUTHOR]

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Many problems caused by loosening, fracture dislocation and hip modular system are due to wear, incompatibility with the environment, cytotoxicity and corrosion of materials used for joint replacement. The previous limitations usually induce the formation of hazardous wastes, causing serious injury to bone tissue, directly affecting patient health and reducing the life of the implant, leading to the risk of further surgery, for early withdrawal of the prosthesis. The aim of this study was characterize the materials of modular hip implants to determine possible causes of early retirement, in samples from different clinics in the city of Barranquilla. The materials found in different modular pairs removed were polymer-ceramic and polymer-metal type, such as PMMA, UHMWPE, Ti6Al4V and Co-Cr-Mo. The characterization was developed from medical diagnosis in order to analyze the possible causes and conditions with greater impact, causing the early retirement of hip implants. The samples were characterized by X-Ray Diffraction, Optical Microscopy and Scanning Electron Microscopy. In the case of polymeric component, this was characterized by TGA. The results showed topographical similarities between modular pairs polymer-metal type. The presence of microcracks shows additional embrittlement in the structure of the implant due to environment. The other hand the polymeric component showed cracks and scratchs due to third body wear in the bearing zone and significant evidence of fracture in the femoral component. In the acetabular component were observed different patterns of adhesive and corrosive wear. [ABSTRACT FROM AUTHOR]

Samples were taken of four marginal regions of the placenta and one of central region which were examined with conventional procedures of scanning electron microscopy previously being observed with light microscopy. Villi of another case of induced abortion at same gestational week were taken as control. Five specimens of each region were selected in delivery room and fixed in 2 percent of glutaraldehyde for their processing. The results showed immature intermediate villi with deposits of fibrinoid and scarce syncytial sprouts. The placental villi showed trophoblastic surface absent of microvilli and with a dense stroma or fibrotic. The surface no showed abundant syncytial sprouts. Villus scalloping with trophoblastic invaginations, were noted without alterations in branching of placental villi. It was found absence of placental hyperplasia or of stromal cisterns. The observations in the studied placenta exhibited a morphological pattern according to week 16 which no permit to predict about abnormal karyotypic. These no karyotyped samples observed sugest that mutations linked to X chromosome during blastogenesis could be cause of the multiple inherited fetal malformations. [ABSTRACT FROM AUTHOR]

Copyright of Revista Internacional de Desastres Naturales, Accidentes e Infraestructura Civil is the property of University of Puerto Rico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Superficies y Vacío is the property of Sociedad Mexicana de Ciencia y Tecnologia de Superficies y Materiales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dry powder method is a solid-state processing technique involving constant milling of the initial compounds for later calcination. This technique was used to prepare the compounds presented in this essay, using TiO2 and MgO in diferentes rates. To analyze the resulting compounds' morphology, Scanning electron microscope (SEM) was used. In the images taken from the TiO2 sample, groups of agglomerations and of grains were found. Nevertheless, it maintains a certain round pattern in both groups, in the shape of micrograins of 0.5-1 µm. SEM images from the MgO sample are typically laminar with barely a few microns of width. The comparative studies of their structural and spectral characteristics through X-ray Diffraction (XRD) confirmed the individual structure of each compound and also, new spectral lines are obtained which suggests that titanates were formed during the process. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recently, molecular materials have been developed because of their electrical properties which give conductor, semiconductor, or superconductor behavior. In this work, the synthesis of new materials formed from Ntrifluoromethanesulfonyl- 1-azahexa-1, 3, 5-triene species and K3[Cr(C2O4)3]⋅3H2O is reported. NTrifluoromethanesulfonyl- 1-azahexa-1,3,5-trienes compounds, which are highly functionalised pentametines, have also been studied due to its interesting physical and chemical properties. These compounds are especially interesting from a structural point of view for some reasons; in a neutral form, they show an extensive electronic delocalisation, which confers them a very particular chemical behaviour. This study is focused on the Molecular Materials preparation by means of two different electrosynthesis techniques: electrocrystallization in conventional cells, and electrosynthesis in the electrochemical module of an Atomic Force Microscope (AFM). The newly synthesized materials were characterized by Scanning Electron Microscope (SEM-EDS). [ABSTRACT FROM AUTHOR]

Objectives: To investigate Leptospira biflexa serovar Andamana, JNS strain ultrastructure using the metallic replication technique, ultrafine cuts, and negative staining for transmission electron microscope and scanning electron microscope high and ultra-high resolution imaging. Materials and methods: Andamana serovar, JNS strain logarithmic phase cultures, 12-15 x 106 cell/mL isolated from one patient were used. Negative staining, ultrafine slicing and metallic replication methods were used for transmission electron microscopy. For scanning electron microscopy, high and ultra-high resolution samples with gold and platinum coating were used. Results: Using the metallic replication method the external structure of individual cells was defined for Leptospira biflexa, Andamana serovar using transmission electron microscopy. Using the negative staining technique the three-layer external membrane could be seen, as well as axial filaments, cytoplasmic membrane, granular cytoplasm with electron-dense inclusions, «balloon» formations, «terminal structure» «terminal appendages», and also the electron-permeable inclusions, all of these were clearly defined. The typical morphology of the microorganism was observed using fine slices on scanning electron microscopy. Conclusions: For the first time we report the metallic replication technique for determining the external morphology in individual Leptospira biflexa, Andamana serovar, JNS strain, and this technique offers advantageous results compared to other methods. Ultrastructure and electron-permeable inclusions within the cytoplasm at a 120 000 power 20 KV were clearly seen using negative staining. Scanning electron microscopy was also useful for confirming the helical structure of the microorganism. [ABSTRACT FROM AUTHOR]

The shaft and the bearing of sugar cane mill undergo excessive wear under normal operation conditions. Optical microscope and scanning electron microscope were used to characterize surface phenomena in the tribological pair steelbronze. Abrasive particle marks were founded on the surface of the shaft; they reduce the fatigue strength, since they induce the superficial crack growth. The cracks grow in a semilliptical or circumferential shape. Over heating of the bearing do produce lead segregation and fusion, promoting the cracks formation and propagation. [ABSTRACT FROM AUTHOR]

The new species Muhlenbergia monandra, endemic to Peru, is described and illustrated. The species is distinguished by possessing longer glumes than anthoecium, spikelike inflorescence, and cleistogamous florets with one stamen. The leaf blade anatomy is described, illustrated, and the distinguishing characters are given. Scanning Electron Microscope observations about the epidermis of the lemma and glumes are made. The taxonomic position is discussed and some remarks about the related annual species of South America are included. [ABSTRACT FROM AUTHOR]

The pollen morphology of nine species of Macroptilium (Benth.) Urb.: M. panduratum (Benth.) Maréchal & Baudet, M. longepedunculatum (Benth.) Urb., M. lathyroides (L.) Urb., M. bracteatum (Benth.) Maréchal & Baudet, M. erythroloma (Benth.) Urb., M. fraternum (Piper) Juárez & Pérez, M. psammodes (Lindman) Drewes & Palacios, M. prostratum (Benth.) Urb. and M. arenarium (Bacigalupo) Drewes & Palacios were studied with the photonic and scanning electron microscope. It is possible to differenciate them in two groups: 1) an homogeneous one, section Macroptilium, with colporate, spherical and reticulate or microreticulate grains; 2) an heterogeneous one, section Microcochle (Benth.) Lackey, with porate or colporate, suboblate grains with different ornamentation. In the section Macroptilium the separation at species level is difficult due to the similarity of their grains, but in the section Microcochle they can be recognized by the type of ornamentation. The main purpose of this paper is to determine the pollen diagnostic characters that allow species identification. [ABSTRACT FROM AUTHOR]

The valve morphology of Surirella ovalis Brébisson from El Divisorio Stream, Argentina was studied in the light and scanning electron microscope. Three forms are described and illustrated, extending the description of this species. [ABSTRACT FROM AUTHOR]

Twenty eight species and varieties of Diatoms from Chubut (República Argentina), were studied using both light and scanning electron microscope. Ten of them are new for this region. Furthermore, Rhizosolenia imbricata var. minima Rivera is recorded for the first time for the South Atlantic Ocean; Rhizosolenia setigera fa. pungens (Cleve) Brunel and Chaetoceros borealis fa. solitaria Cleve represent new records for Argentina. [ABSTRACT FROM AUTHOR]

A new species of Chaetothylax, an exclusively American genus, is described and its affinities with C. rothschuhii Lindau, a Central American species, are discussed. Its pollen grains are studied under the scanning electron microscope. [ABSTRACT FROM AUTHOR]

Three species of freshwater Bacillarophyceae, Stephanodiscus minutulus (Kützing) Cleve et Möller, Navicula subminuscula Manguin and Caloneis amphisbaena (Bory) Cleve are mentioned for the first time in Argentina and are studied in the light and scanning electron microscope. Each taxa is described and illustrated. [ABSTRACT FROM AUTHOR]

Se comenta brevemente sobre la disponibilidad de microscopios electrónicos de barrido para la investigación científica en Cuba.