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Scanning Electron Microscope Observations (scanning + electron_microscope_observation)
Selected AbstractsRF-MBE growth of InN on 4H-SiC (0001) with off-anglesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7-8 2010Misao Orihara Abstract We have grown InN on 4H-SiC (0001) substrates with various off-angles by RF-N2 plasma molecular beam epitaxy (RF-MBE). Scanning electron microscope observation revealed that InN films grown on 4H-SiC (0001) substrates with off-angles of 4° and 8° are very smooth and that there are no voids which have often observed for InN epitaxial layers. X-ray diffraction reciprocal space maps for InN grown on 4H-SiC (0001) showed that the c-axes of InN grown on 4H-SiC 4° and 8° off substrates are inclined by 0.35° and 0.8°, respectively, toward the misorientation of the substrate while the c-axis of InN is parallel to that of 4H-SiC for the on-axis substrate. Strong PL peak was observed from InN grown on 4° off substrate at 0.68 eV at 15 K. The PL peak was clearly observed even at room temperature and simply shifted to lower energies with increasing temperature. The difference in the PL peak energy between at 15 K and 300 K was 20 meV, which is reasonable taking into account the difference in the thermal coefficients of InN and SiC (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Relationships between the olive fly and bacteriaJOURNAL OF APPLIED ENTOMOLOGY, Issue 9-10 2008P. Sacchetti Abstract The relationship between the olive fly population and epiphytic bacteria of the olive tree was investigated by carrying out a 1-year survey in the field. The olive fly population affected the number of bacteria present on the olive surface. Scanning electron microscope observations demonstrated that bacteria may be ingested by the fly's mouth apparatus through the midline of the pseudotracheae. DNA amplification of the oesophageal bulb content using 16S bacteria universal primers and DNA sequencing evidenced that Candidatus Erwinia dacicola was the predominant species present. The role of bacteria in olive fly biology is discussed. [source] Onychomycosis caused by Alternaria spp. in Tuscany, Italy from 1985 to 1999MYCOSES, Issue 3-4 2001C. Romano Alternaria alternata; Alternaria chlamidospora; Nagelinfektionen; Itraconazol. Summary. Cutaneous phaeohyphomycosis due to Alternaria spp. is reported with increasing frequency, especially in patients with immune deficiency. Onychomycosis caused by this mould is still rarely observed. Here we report nine cases observed in Tuscany in the period 1985,99; the agent was Alternaria alternata in eight cases and Alternaria chlamidospora in one. Diagnosis was made on the basis of repeated direct microscopic mycological examination and culture, confirmed by scanning electron microscope observation of fragments of colonies. In most cases, the clinical manifestations were dystropy and distal subungual hyperkeratosis of one or two nails of the feet or hands. Seven cases were treated with oral itraconazole, successfully in six cases, as clinical and mycological recovery was confirmed at follow-up 1 year later. Zusammenfassung. Kutane Phaeohyphomykosen durch Alternaria spp. werden immer häufiger beschrieben, besonders bei Patienten mit gestörter Infektabwehr. Andererseits sind Onychomykosen durch diese Pilzerreger nur selten zu beobachten. Wir berichten über 9 Fälle von Onychomykosen durch Alternaria spp., die innerhalb eines Zeitraums von 14 Jahren (1985,99) beobachtet worden sind. In 8 Fällen wurde Alternaria alternata und in einem Fall Alternaria chlamidospora isoliert. Die Diagnose wurde nach wiederholtem Nachweis der selben Spezies sowohl in Nativpräparaten als auch in Kultur gestellt und durch elektromikroskopische Untersuchungen der Kolonien bestätigt. Klinisch waren in den meisten Fällen dystrophische Veränderungen und distale subunguale Onychomykose an einem oder mehreren Finger- oder Fußnägeln zu beobachten. 7 Patienten wurden systemisch mit Itraconazol behandelt. In 6 dieser Fälle wurde eine klinische und mykologische Heilung erzielt. Während einjähriger Nachbeobachtungzeit blieben die Patienten rezidivfrei. [source] Schmeissneria: An angiosperm from the Early JurassicJOURNAL OF SYSTEMATICS EVOLUTION, Issue 5 2010Xin WANG Abstract, The origin of angiosperms has been a focus of intensive research for a long time. The so-called pre-Cretaceous angiosperms, including Schmeissneria, are usually clouded with doubt. To expel the cloud around the enigmatic Schmeissneria, the syntype and new materials of Schmeissneria collected previously in Germany and recently in China are studied. These materials include female inflorescences and infructescences. The latter are old materials but were under-studied previously. Light microscopy and scanning electron microscope observations indicate that the fruits in these infructescences have in situ seeds enclosed, and that the ovaries are closed before pollination. Thus the plants meet two strict criteria for angiosperms: angiospermy plus angio-ovuly. Placing Schmeissneria in angiosperms will extend the record of angiosperms up to the Early Jurassic, more compatible with many molecular dating conclusions on the age of angiosperms, and demanding a reassessment of the current doctrines on the origin of angiosperms. Although the phylogenetic relationship of Schmeissneria to other angiosperms apparently is still an open question, this study adds to research concerning the origin of angiosperms. [source] Surface alteration of Saccharomyces cerevisiae induced by thymol and eugenolLETTERS IN APPLIED MICROBIOLOGY, Issue 6 2004S. Bennis Abstract Aims:, This study aims to bring some information about the mechanism of the fungicidal action of thymol and eugenol; phenolic major components of thyme and clove essential oils respectively. Saccharomyces cerevisiae was used as yeast model. Methods and Results:, Treatment of yeast cells with these components led to their lysis as shown by the release of substances absorbing at 260 nm. In addition, scanning electron microscope observations revealed that the surface of the treated cells was significantly damaged. Conclusions:, Antifungal activity of thymol and eugenol involve alteration of both membrane and cell wall of the yeast. Significance and Impact of the Study:, This work is a preliminary contribution aiming to develop a new generation of efficient and natural antifungal agents. [source] | ||||||||||