Microscopy

Non-linear microscopy of smooth muscle cells in artificial extracellular matrices made of cellulose

by Nihal Engin Vrana

Authors: Christian Brackmann, Jan-Olof Dahlberg, Nihal Engin Vrana, Caitriona Lally , Paul Gatenholm, Annika Enejder,
Published in Journal of Biophotonics

Non-linear microscopy has been used to characterize bovine smooth muscle cells and their proliferation, migration, and... more Non-linear microscopy has been used to characterize bovine smooth muscle cells and their proliferation, migration, and differentiation in hydrogel cellulose scaffolds, toward the development of fully functional blood vessel implants. The extracellular matrix (ECM) composed of cellulose and endogenous collagen fibers was imaged using Second Harmonic Generation (SHG) microscopy and the cell morphology by Coherent Anti-Stokes Raman Scattering (CARS) microscopy. Images prove that cells adhere on the cellulose scaffold without additional surface modification and that both contractile and proliferating phenotypes are developed. This work shows that non-linear microscopy contributes with unique insights in cell interactions with (artificial) ECM components and has the potential to become an established characterization method in tissue engineering.

Quantitation of cellular dynamics in growing Arabidopsis roots with light sheet microscopy

by Giovanni Sena

The microscopic (optical and SEM) examination of putrefaction fluid deposits (PFD). Potential interest in forensic anthropology

by Patrice Georges

Co-authored with "P. Charlier, F. Bouchet, I. Huynh-Charlier, R. Carlier, V. Mazel, P. Richardin, L. Brun, J. Blondiaux, G. Lorin de la Grandmaison", published in "Virchows Arch", 453, 2008.

DOI 10.1007/s00428-008-0670-1

This article describes the potential interest in physical and forensic anthropology of the microscopic analysis of... more This article describes the potential interest in physical and forensic anthropology of the microscopic analysis of residues of putrefaction fluid, a calcified deposit frequently found associated with bone rests. Its sampling and analysis seem straightforward and relatively reproducible. Samples came from archeological material (Monterenzio Vecchia, an Etruscan necropolis from the north of Italy dated between the fifth and third century B.C.; body rests of Agnès Sorel, royal mistress died in 1450 A.D.; skull and grave of French King Louis the XI and Charlotte of Savoy dated from 1483 A.D.). All samples were studied by direct optical microscope and scanning electron microscopy. Many cytological, histological, and elemental analysis were possible, producing precious data for the identification of these remains and, in some cases, the cause of death.

Performance of melamine modified urea–formaldehyde microcapsules in a dental host material

by Noor Hayaty Abu Kasim

Urea-formaldehyde (UF) microcapsules filled with dicyclopentadiene (DCPD) show potential for making self-healing... more Urea-formaldehyde (UF) microcapsules filled with dicyclopentadiene (DCPD) show potential for making self-healing dental restorative materials. To enhance the physical properties of the capsules, the urea was partially replaced with 0-5% melamine. The microcapsules were analyzed by different microscopic techniques. DSC was used to examine the capsule shell, and the core content was confirmed by (1)H NMR spectroscopy. Capsules in the range of 50-300 mu m were then embedded in a dental composite matrix consisting of bisphenol-A-glycidyl dimethacrylate (Bis-GMA) and triethylene-glycol dimethacrylate (TEGDMA). Flexural strength, microhardness, and nanoindentation hardness measurements were performed on the light-cured specimens. Optical microscopy (OM) examination showed a random distribution of the microspheres throughout the host material. The incorporation of small amounts of the microcapsules did not affect the performance of the matrix material. Scanning electron microscopy (SEM) analysis revealed excellent bonding of the microcapsules to the host material which is a characteristic of utter importance for maintaining the very good mechanical properties of a dental composite with self-healing ability.

Optical Characterisation of Diesel, RME and Kerosene Sprays by Microscopic Imaging

by Cyril Crua

High-Speed Microscopic Imaging of the Initial Stage of Diesel Spray Formation and Primary Breakup

by Cyril Crua

Technician or researcher? A visual answer

by Hugues Plisson

PLISSON H. et LOMPRÉ A. 2008. Technician or researcher? A visual answer. In: "Prehistoric Technology" 40 years later: Functional studies and the Russian legacy. / dir par Longo L. et skakun N. vol 1783. Oxford: BAR, 2008 p.503-508.

Naming the field of research initiated by S.A. Semenov has been a subject of debate, for the term « traceology »,... more Naming the field of research initiated by S.A. Semenov has been a subject of debate, for the term « traceology », which he created, is often thought to be restrictive considering the current research stakes, which are not identified by their means but their
goals. However Semenov’s work shows the wide range of his research, from the most basic methodological aspects, to the human technical evolution process, revealed by the reading of use-wear and manufacturing traces. Using the term “functional analysis” does not account for the potential of traceology.
If traceologists form a scientific community, it is because they acknowledge a common language: traces on archaeological artefacts. Thus documenting those traces is the first step to any demonstration. The validity of the proposed interpretation depends on the quality of this documentation. It then appears essential not to despise the technical basis of our work and to take special care in the quality of the published illustrations.

The microscopic glance: Spiritual exercises, the microscope and the practice of wonder in early modern science

by Claude-Olivier Doron

Draft, to be published in Vasalou, Sophia  (dir.), Practices of Wonder, Wipf and Stock, 2012

I argue in this essay that microscope was used in many texts from the end of the XVIIth century until at least the... more I argue in this essay that microscope was used in many texts from the end of the XVIIth century until at least the middle of the XVIIIth, as a kind of apparatus to practice and exercise wonderment. Wonderment is not here to be defined as an immediate emotion that arises from strange or exceptional phenomena as extraordinary wonders or miracles; it is a complex emotion that is produced through a disciplined experience, that requires practice and sometimes efforts, has to be kept alive, and that is extracted from the very ordinary objects of the world, even the most despised as insects or small things like needles, rain drops, etc. I argue that the microscope served as a way to give access to a certain kind of experience of wonderment, what I call an “objective mystical experience” that was supposed to produce an inner transformation of the observer, with ethical as well as cognitive dimensions.  It can be read as a specific technique of the self, blurring the usual frontier between the scientific and the religious self, and as a spiritual exercise in the very strict meaning Ignatius de Loyola gave to the concept: exercises like humiliating human pride, exposing its pretensions, plunging him into astonishment and discovering its nullity, like celebrating God’s almighty wisdom in each element of the World, meditating on order or on celestial life, etc. And in each of these exercises, the production of wonderment appears as the key element

High Sensitivity Surface-Enhanced Raman Scattering in Solution using Engineered Silver Nanosphere Dimers

by Desiré Whitmore

Remote multi-color excitation using femtosecond propagating surface plasmon polaritons in gold films

by Desiré Whitmore

The use of high glass temperature polymers in the production of transparent, structured surfaces using nanoimprint lithography

by Javier G. Fernandez

Co-authored with Christopher A. Mills and Josep Samitier, Published in "Microelectronic Engineering"

Polymers with high glass transition temperatures, fluorinated ethylene propylene copolymer (FEP) and poly(ethylene... more Polymers with high glass transition temperatures, fluorinated ethylene propylene copolymer (FEP) and poly(ethylene naphthalate) (PEN), have been used in imprint lithography as a protective support layer and as a secondary mould, to imprint superficial structures into a polymer with a lower glass transition temperature, namely poly(methyl methacrylate) (PMMA). As a support layer, FEP replaces fragile silicon based supports for the production of freestanding, structured sheets of PMMA, useful, for example, in biomedical applications where transmittance optical microscopy is required. Secondary PEN moulds, produced by imprinting using silicon-based primary moulds, have been used to transfer sub-micrometer tall structures to a freestanding PMMA sheet. Similarly, hole structures, with different dimensions, have been embossed in both sides of a PMMA sheet simultaneously

Ion Beam Analysis Of Silicon Based Surfaces And Correlation With Surface Energy Measurements

by Nicole Herbots

Qian Xing, N. Herbots, M. Hart, J. D. Bradley, B. J. Wilkens, D. A. Sell, Clive H. Sell, Henry Mark Kwong Jr., R. J. Culbertson, S. D. Whaley

Department of Physics, Arizona State University, Tempe, AZ 85287-1504
Associated Retina Consultants, 7600 N 15th Street, Suite 155, Phoenix, AZ 85020

Citation: AIP Conf. Proc. 1336, 201 (2011); doi: 10.1063/1.3586089

The water affinity of Si-based surfaces is quantified by contact angle measurement and surface free energy to explain... more The water affinity of Si-based surfaces is quantified by contact angle measurement and surface free energy to explain hydrophobic or hydrophilic behavior of silicone, silicates, and silicon surfaces. Surface defects such as dangling bonds, surface free energy including Lewis acid-base and Lifshitz-van der Waals components are discussed. Water nucleation and condensation is further explained by surface topography. Tapping mode atomic force microscopy (TMAFM) provides statistical analysis of the topography of these Si-based surfaces. The correlation of the above two characteristics describes the behavior of water condensation at Si-based surfaces. Surface root mean square roughness increasing from several Å to several nm is found to provide nucleation sites that expedite water condensation visibly for silica and silicone. Hydrophilic surfaces have a condensation pattern that forms puddles of water while hydrophobic surfaces form water beads. Polymer adsorption on these surfaces alters the water affinity as well as the surface topography, and therefore controls condensation on Si-based surfaces including silicone intraocular lens (IOL). The polymer film is characterized by Rutherford backscattering spectrometry (RBS) in conjunction with 4.265 MeV 12C(α, α)12C, 3.045 MeV 16O(α, α)16O nuclear resonance scattering (NRS), and 2.8 MeV elastic recoil detection (ERD) of hydrogen for high resolution composition and areal density measurements. The areal density of hydroxypropyl methylcellulose (HPMC) film ranges from 1018 atom/cm2 to 1019 atom/cm2 gives the silica or silicone surface a roughness of several Å and a wavelength of 0.16 ± 0.02 μm, and prevents fogging by forming a complete wetting layer during water condensation.
Keywords: ERD, NRS, RBS, AFM, polymer film, silicone, silica, Si(100), contact angle, surface free energy, surface topography, intraocular implant.

Ion-solid interactions during ion beam deposition of 74Ge and 30Si on Si at very low ion energies (0-200 eV range)

by Nicole Herbots

ION-SOLID INTERACTIONS DURING ION BEAM DEPOSITION OF 74Ge AND 30Si ON Si AT VERY LOW ION ENERGIES (O-2OO eV RANGE)*
N. HERBOTS, B.R. APPLETON, T.S. NOGGLE, R.A. ZUHR and S.J. PENNYCOOK
Solid State Division, Oak Ridge National Laboratory, PO Box X, Oak Ridge, TN 37831, USA
Nuclear Instruments and Methods in Physics Research B13 (1986) 250-258 North-Holland, Amsterdam

Atomic collisions in solids in the 40-200 eV energy range have been studied both theoreticalIy and experimentaIiy to... more Atomic collisions in solids in the 40-200 eV energy range have been studied both theoreticalIy and experimentaIiy to determine the feasibility of the ion beam deposition (IBD) of amorphous and/or epitaxial layers. IBD was first modeled by a rate equation including the target sputtering yield and the ion self-sputtering, range and range straggling. To obtain preliminary values of those parameters, Monte Carlo simulations with TRIMSPUT were used. The surface binding energy (SBE) appeared to be an important parameter of the simulation for sputtering yields under 200 eV. By fitting the SBE with available sputtering data for Ar on Si below 1 keV, a very good agreement waso obtained between simulations and sputtering data of other ion-target combinations. Experimentally, 30Si and 74Ge ions were deposited on Si( 100) at 300 K and 700 K. Cross-section TEM combined with ion scattering and ion channeling showed that IBD can provide very thin (3 nm) though perfectly continuous films with sharp interfaces (<l nm). IBD damage to the substrate saturates as a function of dose, is negligible below 4OeV, and presents an interesting annihilation/long range diffusion behavior as a
function of the temperature during irradiation.

Antonio Vallisneri e la questione dei vermicelli spermatici: un’indagine storico-naturalistica

by Francesco Luzzini

in From Makers to Users. Microscopes, Markets, and Scientific Practices in the Seventeenth and Eighteenth Centuries, Proceedings of the International Workshop on the History of Microscopy (Milan, October 13-14, 2004), edited by Dario Generali and Marc Ratcliff, Florence, Olschki, 2007, pp. 73-89.

This paper deals with the identification of the microscope used by
the Italian physician and naturalist Antonio... more This paper deals with the identification of the microscope used by
the Italian physician and naturalist Antonio Vallisneri (1661-1730) during his experimental research activity.
The investigation was structured in three phases: a) a first text analysis on published and manuscript sources, looking for information about the microscope(s) used by Vallisneri; b) an hypothesis was put forward based on the chronological and descriptive compliance between the examined writings and the technological level achieved by eighteenth- and seventeenth-century microscopy; c) there was an experimental verification of the hypothesis, through the reproduction of observations reported by Vallisneri, using similar material and instrument.
The letters written by Vallisneri to Louis Bourguet and Jacopo Riccati between 1713 and 1721 were the most important documents for the purpose of this research.
They concern the observation of spermatozoa in rabbit semen. In these letters Vallisneri mentioned some «English microscopes with eight lens orders» that fitted the description of the screw-barrel microscope by the English craftsman James Wilson in three pamphlets issued between 1702 and 1711. Original copies of Wilson-type microscopes are preserved at the Muse´e d’Histoire des Sciences of Geneva, where the possibility of manipulating them allowed the experimental observation of the rabbit semen. Among the instruments preserved there, inventory no. 466 was mainly considered: a Wilson-type microscope on a brass stand – a change introduced by John Cuff in the early 1740s. The spermatic cells were clearly observed through three lenses, with magnifications ranging from 120 X to 300 X.
Though it must be pointed out that these lenses were not standardised, this result reasonably confirmed the hypothesis, e.g. the microscope used by Vallisneri for the observation of spermatozoa was a screw-barrel instrument made by James Wilson, probably in the first decade of the eighteenth century. In the conclusion I discuss the role played by single lens microscopes in Vallisneri’s activity and in the development of early eighteenth-century scientific research and markets in northern Italy.

Controlled light exposure microscopy reveals dynamic telomere microterritories throughout the cell cycle

by Winnok H. De Vos

W. De Vos, R. Hoebe, G. Joss, W. Haffmans, S. Baatout, P. Van Oostveldt and E. Manders
Cytometry Part A 75(5), p428-439, 2009.

Telomeres are complex end structures that confer functional integrity and positional stability to human chromosomes.... more Telomeres are complex end structures that confer functional integrity and positional stability to human chromosomes. Despite their critical importance, there is no clear view on telomere organization in cycling human cells and their dynamic behavior throughout the cell cycle. We investigated spatiotemporal organization of telomeres in living human ECV-304 cells stably expressing telomere binding proteins TRF1 and TRF2 fused to mCitrine using four dimensional microscopy. We thereby made use of controlled light exposure microscopy (CLEM), a novel technology that strongly reduces photodamage by limiting excitation in parts of the image where full exposure is not needed. We found that telomeres share small territories where they dynamically associ- ate. These territories are preferentially positioned at the interface of chromatin domains. TRF1 and TRF2 are abundantly present in these territories but not firmly bound. At the onset of mitosis, the bulk of TRF protein dissociates from telomere regions, territories disintegrate and individual telomeres become faintly visible. The combination of stable cell lines, CLEM and cytometry proved essential in providing novel insights in compartment-based nuclear organization and may serve as a model approach for investigating telomere-driven genome-instability and studying long-term nuclear dynamics.

Improving depth of field resolution for palynological photomicrography

by Antoine Bercovici

Bercovici, A., Hadley, A., Villanueva-Amadoz, U. (2009). Improving depth of field resolution for palynological microphotography, Palaeontologia Electronica, v. 12(2), 12 p.

Optical microscopy continues to be the preferred method for imaging in paleopalynology. While usefulness of other... more Optical microscopy continues to be the preferred method for imaging in paleopalynology. While usefulness of other tools, such as the scanning electron microscope, is not questioned, the ease of use and timely results of optical microscopy remains unsurpassed. However, obtaining good quality photomicrographs requires the use of the highest magnifying power objectives available, which are inevitably associated with very limited depth of field. To avoid the need for multiple photomicrographs in order to fully describe each palynomorph, a software solution for reconstructing depth of field is proposed. This solution allows for keeping the main advantages of high magnifying power objectives (better resolution and improved contrast) while suppressing their main weakness. In addition, photomicrographs published using depth of field reconstruction have a more natural appearance, similar to when directly viewed with the eye under the microscope. While this paper deals primarily with the usage of depth of field reconstruction for the enhancement of palynological photomicrograph, the technique can be applied similarly to many other paleontological and geological objects as well.

Localization and movement of mineral oil in plants by fluorescence and confocal microscopy

by Rosemary White

Tan BL, Sarafis V, Beattie GAC, White RG, Darley EM, Spooner-Hart R (2005) Localization and movement of mineral oil in plants by fluorescence and confocal microscopy. Journal of Experimental Botany 56: 2755-2763

Fluorescence and confocal laser scanning microscopy were explored to investigate the movement and localization of... more Fluorescence and confocal laser scanning microscopy were explored to investigate the movement and localization of mineral oils in citrus. In a laboratory experiment, fluorescence microscopy observation indicated that when a ‘narrow’ distillation fraction of an nC23 horticultural mineral oil was applied to adaxial and opposing abaxial leaf surfaces of potted orange [Citrus × aurantium L. (Sapindales: Rutaceae)] trees, oil penetrated steadily into treated leaves and, subsequently, moved to untreated petioles of the leaves and adjacent untreated stems. In another experiment, confocal laser scanning microscopy was used to visualize the penetration into, and the subsequent cellular distribution of, an nC24 agricultural mineral oil in C. trifoliata L. seedlings. Oil droplets penetrated or diffused into plants via both stomata and the cuticle of leaves and stems, and then moved within intercellular spaces and into various cells including phloem and xylem. Oil accumulated in droplets in intercellular spaces and within cells near the cell membrane. Oil entered cells without visibly damaging membranes or causing cell death. In a field experiment with mature orange trees, droplets of an nC23 horticultural mineral oil were observed, by fluorescence microscopy, in phloem sieve elements in spring flush growth produced 4–5 months and 16–17 months after the trees were sprayed with oil. These results suggest that movement of mineral oil in plants is both apoplastic via intercellular spaces and symplastic via plasmodesmata. The putative pattern of the translocation of mineral oil in plants and its relevance to oil-induced chronic phytotoxicity are discussed.

Simultaneous fluorescent Gram staining and activity assessment of activated sludge bacteria

by Jean-Noël Louvet

Assessment of Erythromycin Toxicity on Activated Sludge via Batch Experiments and Microscopic Techniques (Epifluorescence and CLSM)

by Jean-Noël Louvet

). J.N. Louvet, Y. Heluin G. Attik, D. Dumas, O. Potier, M.N. Pons. Process Biochemistry. 2010, 45 (11) pp 1787-1794, 

This study investigates erythromycin toxicity toward activated sludge as a function of exposure time and... more

This study investigates erythromycin toxicity toward activated sludge as a function of exposure time and antibiotic concentration. Batch experiments were conducted and microscopic techniques ranging from bright-field microscopy to epifluorescence and confocal laser scanning microscopy (CLSM), combined with a fluorescent viability indicator (BacLight® Bacterial Viability Kit, Molecular Probes), allowed us to study erythromycin time-kill activity. The erythromycin toxicity was observed at lower concentration when exposure time increased. A 4 μg/L erythromycin concentration was toxic to heterotrophic bacteria on a 5-day time exposure, and a 5 mg/L concentration inhibited nitrification. These findings are in agreement with the microscopic studies, which showed a latency time before the lower antibiotic concentrations began to kill bacteria. Microscope slide wells were used as micro-reactors in which erythromycin concentration ranged from 0.1 to 1 mg/L. After 45 min there were 94% (SD 3.8) of living bacteria in control micro-reactors, 67% (SD 3.1) in micro-reactors that contained 0.1 mg/L erythromycin and 37% (SD 18.6) in micro-reactors that contained 1 mg/L erythromycin. CLSM allowed visualization of isolated stained cells in the three-dimensional structure of damaged flocs.




Keywords: Macrolides; Antibiotic; Inhibition; BacLight; Microscopy

Effets des antibiotiques sur le procédé d'épuration par boues activées. Etude du cas de l'érythromycine du floc bactérien au réacteur biologique

by Jean-Noël Louvet

Thèse de doctorat, présentée et soutenue publiquement le 09/11/2010 pour l'obtention du grade de Docteur de l'INPL (Spécialité Génie des Procédés et des Produits)