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Microscope Slide (microscope + slide)
Selected AbstractsA New Optically Reflective Thin Layer Electrode (ORTLE) Window: Gold on a Thin Porous Alumina Film Used to Observe the Onset of Water ReductionELECTROANALYSIS, Issue 1-2 2004Abstract The fabrication and unique characteristics of a new type of thin layer electrode, an optically reflective thin layer electrode (ORTLE), are described. The electrode was fabricated by the anodization of a thin layer of aluminum sputtered onto a plain glass microscope slide to create a 750,nm-thick porous alumina film. A thin film of gold was then sputtered atop the porous and transparent alumina film. The gold layer remained porous to allow solution into the pores but was optically thick and reflective. Reflectance measurements made through the microscope slide did not interrogate the bulk solution, but show spectral features that shift with the optical properties of the material filling the pores of the alumina film. A simple series of experiments, in which the potential of the ORTLE was stepped negatively to various values in an aqueous sodium sulfate solution, shows that interference fringes shift measurably in the ORTLE spectrum at potentials several hundred millivolts positive of the potential at which gas evolution was visible to the naked eye. [source] Bacillus megaterium spore germination is influenced by inoculum sizeJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002M.L. Caipo Aims:,The effect of spore density on the germination (time-to-germination, percent germination) of Bacillus megaterium spores on tryptic soy agar was determined using direct microscopic observation. Methods and Results:,Inoculum size varied from approximately 103 to 108 cfu ml,1 in a medium where pH=7 and the sodium chloride concentration was 0·5% w/v. Inoculum size was measured by global inoculum size (the concentration of spores on a microscope slide) and local inoculum size (the number of spores observed in a given microscope field of observation). Both global and local inoculum sizes had a significant effect on time-to-germination (TTG), but only the global inoculum size influenced the percentage germination of the observed spores. Conclusions:,These results show that higher concentrations of Bacillus megaterium spores encourage more rapid germination and more spores to germinate, indicating that low spore populations do not behave similarly to high spore populations. Significance and Impact of the Study:,A likely explanation for the inoculum size-dependency of germination would be chemical signalling or quorum sensing between Bacillus spores. [source] Digital photography: A primer for pathologistsJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2004Roger S. Riley Abstract The computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high-resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge-coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than $2,500 that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11×14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images. There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio-enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare "zoomable" panoramas that encompass a large part of a microscope slide and closely simulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Later in this decade, interactive immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and to obtain experimental data. J. Clin. Lab. Anal. 18:91,128, 2004. © 2004 Wiley-Liss, Inc. [source] The evolution of screeningPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 1 2001J. A. Muir Gray CBE Botany is usually considered to be the gentlest of sciences with botanists being regarded as people who study relatively safe specimens, compared with, for example, anthropologists or microbiologists. However, botanists have their moments, particularly when collecting new species. The great botanists of the eighteenth and nineteenth centuries risked their lives in collecting and bringing back species, which we now take for granted, and Robert Brown was one of these adventurers, a young Scot who accompanied Sir Joseph Banks to New Holland. It was not, however, for his adventurous lifestyle that Brown is remembered but for his startling observation of the movements of pollen grains on a microscope slide. He noted that the pollen grains were in perpetual agitated motion, without purpose or direction but full of energy. This motion, called Brownian motion, arises from the movement of molecules, and Brownian motion is the term that has been applied to much of healthcare, including many screening programmes, which have in the past been marked more by the amount of energy and activity than by a clear sense of direction or positive achievement. Copyright © 2001 John Wiley & Sons, Ltd. [source] Profiles of light absorption and chlorophyll within spinach leaves from chlorophyll fluorescencePLANT CELL & ENVIRONMENT, Issue 10 2002T. C. Vogelmann Abstract Chlorophyll fluorescence was used to estimate profiles of absorbed light within chlorophyll solutions and leaves. For chlorophyll solutions, the intensity of the emitted fluorescence declined in a log,linear manner with the distance from ,the ,irradiated ,surface ,as ,predicted ,by ,Beer's ,law. The amount of fluorescence was proportional to chlorophyll ,concentration ,for ,chlorophyll ,solutions ,given ,epi-illumination on a microscope slide. These relationships appeared to hold for more optically complex spinach leaves. The profile of chlorophyll fluorescence emitted by leaf cross sections given epi-illumination corresponded to chlorophyll content measured in extracts of leaf paradermal sections. Thus epifluorescence was used to estimate relative chlorophyll content through leaf tissues. Fluorescence profiles across leaves depended on wavelength and orientation, reaching a peak at 50,70 µm depth. By infiltrating leaves with water, the pathlengthening due to scattering at the airspace : cell wall interfaces was calculated. Surprisingly, the palisade and spongy mesophyll had similar values for pathlengthening with the value being greatest for green light (550 > 650 > 450 nm). By combining fluorescence profiles with chlorophyll distribution across the leaf, the profile of the apparent extinction coefficient was calculated. The light profiles within spinach leaves could be well approximated by an apparent extinction coefficient and the Beer,Lambert/Bouguer laws. Light was absorbed at greater depths than predicted from fibre optic measurements, with 50% of blue and green light reaching 125 and 240 µm deep, respectively. [source] Identification of repertoires of surface antigens on leukemias using an antibody microarrayPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 11 2003Larissa Belov Abstract We have previously described a microarray of cluster of differentiation (CD) antibodies that enables concurrent determination of more than 60 CD antigens on leukocytes. This procedure does not require protein purification or labeling, or a secondary detection system. Whole cells are captured by a microarray of 10 nL antibody dots immobilized on a nitrocellulose film on a microscope slide. Distinct patterns of cell binding are observed for different leukemias or lymphomas. These haematological malignancies arise from precursor cells of T- or B-lymphocytic, or myeloid lineages of hematopoiesis. The dot patterns obtained from patients are distinct from those of peripheral blood leukocytes from normal subjects. This microarray technology has recently undergone a number of refinements. The microarray now contains more CD antibodies, and a scanner for imaging dot patterns and software for data analysis provide an extensive immunophenotype sufficient for diagnosis of common leukemias. The technology is being evaluated for diagnosis of leukemias with parallel use of conventional diagnostic criteria. [source] Effects of Cryopreservation on Bull Spermatozoa Distribution in Morphometrically Distinct SubpopulationsREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2007J Rubio-Guillén Contents Assisted sperm morphometry analysis (ASMA) was used in this study to determine the effects of cryopreservation on bull spermatozoa distribution in morphometrically distinct subpopulations. Ejaculates were collected from five bulls and were divided. One portion was diluted at 30°C in a skim milk,egg yolk medium, containing glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for a minimum of 200 sperm heads were analysed from each sample by means of the Sperm-Class Analyser® (SCA), and the mean measurements recorded. Our results showed that applying the ASMA technology and multivariate cluster analyses, it was possible to determine that three separate subpopulations of spermatozoa with different morphometric characteristics coexist in bull ejaculates (large, average and small spermatozoa). The mean values of each sperm head dimension among the three subpopulations of spermatozoa were significantly different (p < 0.001). Besides, there were significant (p < 0.001) differences in the distribution of these three sperm subpopulations between fresh and thawed samples. Thus, the percentage of representation of the subpopulation that includes those spermatozoa whose dimensions are the biggest, decreased from 52.06% in extended fresh samples to 15.51% in the thawed ones. Contrarily, the percent of representation of the subpopulation containing the smallest spermatozoa, increased from 8.70% in extended fresh samples to 34.04% in the thawed ones. In conclusion, the present study confirms the heterogeneity of sperm head dimensions in bull semen, heterogeneity that vary through the cryopreservation procedure. [source] A rapid latex agglutination test for gender identification in the Atlantic bluefin tuna, Thunnus thynnus (Linnaeus)AQUACULTURE RESEARCH, Issue 9 2010Elisabetta Micera Abstract A rapid, one-step agglutination assay has been developed, based on latex particles sensitized with antibodies against vitellogenin (Vtg), aimed at Atlantic bluefin tuna, Thunnus thynnus (Linnaeus) (ABFT), gender identification. The egg-yolk precursor protein Vtg was used as a gender marker for the assay as it is a female-specific protein synthesized during reproductive maturation. The presence of Vtg in the plasma was revealed in 60,120 s through an agglutination reaction by mixing small volumes of ABFT plasma and an anti-Vtg antibody-latex suspension on a microscope slide. The effectiveness of the present test was restricted to the months of May and June, concomitant with high circulating Vtg levels. Because of its rapidity and ease of performance in the field, the present gender identification assay could be useful for broodstock management in the aquaculture industry as well as in tagging studies on wild populations. [source] CPA assessment , the regional assessors' experienceCYTOPATHOLOGY, Issue 2007E. Welsh Many individuals within Laboratory Medicine will be unaware that CPA conducts assessments to two different sets of CPA Standards. There are the Standards for the Medical Laboratory and the Standards for EQA Schemes in Laboratory Medicine. The style and format of both sets of standards is very similar with each being presented in eight sections A , H. The EQA standards are almost identical to the laboratory standards with the exception of the E.F and G standards which are specific to EQA schemes. There are approximately 40 EQA Schemes registered with CPA compared with almost 2 500 laboratories. These EQA schemes vary from very large national/international schemes with numerous analytes to small interpretive schemes run by one individual with a personal interest in that specific subject. The large schemes usually come under the UKNEQAS consortia banner and due to their size and configuration do not present undue problems in the assessment process. Smaller interpretive EQA schemes present a challenge both for the scheme and CPA in gaining accreditation. These schemes are usually within the discipline of Histopathology and are regarded as educational rather than proficiency testing schemes. Very frequently, the scheme is organized by a single individual with a collection of microscope slides, storage facilities for the slides and a computer. This presents the Scheme Organizer with great difficulty in complying with the Quality Management System requirements of the CPA Standards. There are a number of models which can be applied in order to satisfy the requirement of the Quality Management System, but ultimately it must be recognized that in some circumstances it is not possible to accredit these small schemes. The NHSCSP Gynae Cytology EQA Scheme is probably the largest EQA scheme within the UK, in respect of the number of participants and the number of staff supporting the scheme. Scheme Management decided that all nine regions of England would apply for accreditation under one CPA Reference Number. This process meant that the scheme would be assessed as a Managed Pathology Network. This is unique in terms of EQA schemes and presented a number of problems not previously encountered in EQA scheme accreditation. This decision meant that all nine regions must comply with a single Quality Management System and other CPA standards whilst allowing flexibility within the system for each region to facilitate the assessment process specific to their user's requirements. The process worked in a satisfactory manner and the overall outcome was not dissimilar to that of other large EQA schemes. The assessment to the current EQA Standards only commenced in April 2006 whilst the Standards for Medical Laboratories commenced in 2003, and it is perhaps not surprising to find that the principal non-conformities are related to the Quality Management System. This parallels the findings encountered in laboratory accreditation. There is an ongoing educational process for Scheme Management and the Facilitators in each region in how to comply fully with the standards and a commitment to quality improvement which ultimately is beneficial to the participant's of the scheme and to patient safety. [source] A pathologist's perspective on bone marrow aspiration and biopsy: I. performing a bone marrow examinationJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2004Roger S. Riley Abstract The bone marrow aspirate and biopsy is an important medical procedure for the diagnosis of hematologic malignancies and other diseases, and for the follow-up evaluation of patients undergoing chemotherapy, bone marrow transplantation, and other forms of medical therapy. During the procedure, liquid bone marrow is aspirated from the posterior iliac crest or sternum with a special needle, smeared on glass microscope slides by one of several techniques, and stained by the Wright-Giemsa or other techniques for micro-scopic examination. The bone marrow core biopsy is obtained from the posterior iliac crest with a Jamshidi or similar needle and processed in the same manner as other surgical specimens. Flow cytometric examination, cytochemical stains, cytogenetic and molecular analysis, and other diagnostic procedures can be performed on bone marrow aspirate material, while sections prepared from the bone marrow biopsy can be stained by the immunoperoxidase or other techniques. The bone marrow procedure can be performed with a minimum of discomfort to the patient if adequate local anesthesia is utilized. Pain, bleeding, and infection are rare complications of the bone marrow procedure performed at the posterior iliac crest, while death from cardiac tamponade has rarely occurred from the sternal bone marrow aspiration. The recent development of bone marrow biopsy needles with specially sharpened cutting edges and core-securing devices has reduced the discomfort of the procedure and improved the quality of the specimens obtained. J. Clin. Lab. Anal. 18:70-90, 2004. © 2004 Wiley-Liss, Inc. [source] Prism coupling characterization of planar optical waveguides made by silver ion exchange in glassPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2005O. Hidalgo Abstract A modified dark-lines method of prism-coupling technique is utilized for the experimental determination of the effective index of propagating modes in a glass planar waveguide. We use to make the waveguides a silver-sodium ion exchange in a nitrate solution and sodalime glass as substrate (microscope slides). The measurements were accomplished by direct HeNe laser beam incidence and sensing the reflected light by a Thorlabs Dec110 optical detector linked to a Protek500 digital multimeter. A LabView virtual instrument was implemented for the automation of the measurement process. The effective indexes measured have been used to calculate the refractive index profile by IWKB method. A comparison with other results shows that our experimental setup is suitable for slab waveguide modes characterization. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A microhistological survey on the trees of a relict subtropical laurel forest from the Macaronesian Islands as a base for assessing vertebrate plant dietBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2005PATRICIA MARRERO A microhistological collection and its respective key on the leaves and fleshy fruits produced by the mostly endemic trees that integrate the relict laurel forest in the Macaronesian Islands are presented. Epidermal tissues from the adaxial and abaxial surfaces of leaves and fruits of 23 species were extracted by scraping and prepared on individual microscope slides. An optical microscope with a camera lucida fixed at magnifications of ×400 was used to analyse and to draw the morphological traits of epidermal tissues to the same scale. Furthermore, quantitative data for those congeneric species were also obtained by using an image analysis program system. The results indicate that this microhistological method permits the differentiation of practically all species of trees present in the Macaronesian laurel forest. Furthermore, most species belonging to the same taxa (genus or family) show a general common pattern in the morphology of the different epidermal traits. Lastly, despite the effort that constitutes the preparation of plant microhistological collections of a determined ecosystem, it is of basic importance because it makes possible the performance of feeding ecological studies of several herbivorous and frugivorous vertebrate species. These results provide crucial information that elucidates the functioning of the food web and energetic flux dynamics of the Macaronesian laurel forest ecosystem. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148, 409,426. 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