Effect of Mg treatment on distribution of inclusions in Fe-O-Al-Mg melt

This study aims to investigate the effect of Mg treatment on the homogenized distribution of inclusions. Deoxidized experiments with Al (0.05%Al) and Al-Mg (0.05%Al + 0.03%Mg) were carried out at 1873 K respectively and the degree of homogeneity in inclusion dispersion, area density, average size and inter-surface distance of inclusions were studied. The attractive capillary force acts on inclusions was analyzed by in-situ observation by confocal laser scanning microscopy and Kralchevsky-Paunov model. The results show that the proportion of inclusions with inter-surface distance at the range of 10–100 µm is up to 60% after Al-Mg deoxidized 1800 s. Compared with Al2O3 inclusion, the area density of MgAl2O4 inclusions is generally more homogeneous. The in-situ observed results indicate that the inclusions in the steel deoxidized by Al are easy to aggregate and small size Al2O3 inclusions tend to gather around large size Al2O3 inclusions, while the inclusions in the steel deoxidized by Al-Mg tend to distribute more homogeneously. Moreover, the calculated results suggest that the attractive capillary force is larger between inclusions with larger size. The attractive capillary force is larger when the value of smaller size inclusions R1 is gradually close to the value of larger size inclusions R2. The relationship between attractive capillary force and the degree of homogeneity in inclusion dispersion is discussed based on Kralchevsky-Paunov model.

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3-D imaging of cells using a confocal laser scanning microscope and digital image processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102560 ◽

1988 ◽

Vol 46 ◽

pp. 96-97

Author(s):

Thomas M. Jovin ◽

Michel Robert-Nicoud ◽

Donna J. Arndt-Jovin ◽

Thorsten Schormann

Keyword(s):

Laser Scanning ◽

Confocal Laser Scanning Microscope ◽

Laser Scanning Microscopy ◽

Confocal Laser Scanning ◽

Confocal Laser ◽

Scanning Microscope ◽

Laser Scanning Microscope ◽

Biochemical Processes ◽

Adjacent Structures

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.

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Influence of Aging on Corrosion Behaviour of the 6061 Cast Aluminium Alloy

Materials ◽

10.3390/ma14081821 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1821

Author(s):

Ting He ◽

Wei Shi ◽

Song Xiang ◽

Chaowen Huang ◽

Ronald G. Ballinger

Keyword(s):

Aluminium Alloy ◽

Laser Scanning ◽

Corrosion Behaviour ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Kelvin Probe ◽

Force Microscopy ◽

The Matrix ◽

6061 Aluminium Alloy

The influence of AlFeSi and Mg2Si phases on corrosion behaviour of the cast 6061 aluminium alloy was investigated. Scanning Kelvin probe force microscopy (SKPFM), electron probe microanalysis (EPMA), and in situ observations by confocal laser scanning microscopy (CLSM) were used. It was found that Mg2Si phases were anodic relative to the matrix and dissolved preferentially without significantly affecting corrosion propagation. The AlFeSi phases’ influence on 6061 aluminium alloy local corrosion was greater than that of the Mg2Si phases. The corroded region width reached five times that of the AlFeSi phase, and the accelerating effect was terminated as the AlFeSi dissolved.

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In Situ 3D-Imaging of the Inner Ear Synapses with a Cochlear Implant

Life ◽

10.3390/life11040301 ◽

2021 ◽

Vol 11 (4) ◽

pp. 301

Author(s):

Kathrin Malfeld ◽

Nina Armbrecht ◽

Holger A. Volk ◽

Thomas Lenarz ◽

Verena Scheper

Keyword(s):

Cochlear Implant ◽

Inner Ear ◽

Laser Scanning ◽

3D Imaging ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Sensory Cells ◽

Residual Hearing ◽

Preparation Methods

In recent years sensorineural hearing loss was found to affect not exclusively, nor at first, the sensory cells of the inner ear. The sensory cells’ synapses and subsequent neurites are initially damaged. Auditory synaptopathies also play an important role in cochlear implant (CI) care, as they can lead to a loss of physiological hearing in patients with residual hearing. These auditory synaptopathies and in general the cascades of hearing pathologies have been in the focus of research in recent years with the aim to develop more targeted and individually tailored therapeutics. In the current study, a method to examine implanted inner ears of guinea pigs was developed to examine the synapse level. For this purpose, the cochlea is made transparent and scanned with the implant in situ using confocal laser scanning microscopy. Three different preparation methods were compared to enable both an overview image of the cochlea for assessing the CI position and images of the synapses on the same specimen. The best results were achieved by dissection of the bony capsule of the cochlea.

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A New Approach to Three-dimensional Reconstructed Imaging of Hormone-secreting Cells and Their Microvessel Environments in Rat Pituitary Glands by Confocal Laser Scanning Microscopy

Journal of Histochemistry & Cytochemistry ◽

10.1177/002215540004800414 ◽

2000 ◽

Vol 48 (4) ◽

pp. 569-577 ◽

Cited By ~ 26

Author(s):

J. Itoh ◽

K. Kawai ◽

A. Serizawa ◽

K. Yasumura ◽

K. Ogawa ◽

...

Keyword(s):

Confocal Laser Scanning Microscopy ◽

Laser Scanning ◽

Endocrine Cells ◽

Laser Scanning Microscopy ◽

Confocal Laser Scanning ◽

Scanning Microscopy ◽

Confocal Laser ◽

Rat Pituitary ◽

Pituitary Glands ◽

The Relationship

There has been considerable interest in the relationship between hormone-secreting endocrine cells and their microvessels in human pituitary gland. However, microcirculatory networks have rarely been studied in three dimensions (3D). This study was designed to visualize and to reveal the relationship between hormone-secreting endocrine cells and their microvessel environment in 3D, using rat pituitary glands under various (hyper/hypo) experimental conditions by confocal laser scanning microscopy (CLSM). Female adult Wistar rats were used after bilateral adrenalectomy or ACTH administration for 2 weeks. Clear 3D reconstructed images of ACTH cells, the microvessel network and counterstained nuclei were obtained at a maximal focus depth of 1 mm by CLSM without any background noise. In the hyperfunctional state, slender cytoplasmic processes of hypertrophic stellate ACTH cells frequently extended to the microvessels. In the hypofunctional state, ACTH cells appeared atrophic and round with scanty cytoplasm, and cytoplasmic adhesions to microvessel network patterns were inconspicuous. Therefore, 3D reconstructed imaging by CLSM is a useful technique with which to investigate the microvessel environment of hormone-secreting cells and has the potential to reveal dynamic hormone-secreting pathways.

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), confocal laser scanning microscopy (Eberl et al. 1997) or enumerated by flow cytometry (Tombolini et al. 1997). A further advantage of GFP, over other biomarkers, is the fact that no other energy source or substrate addition is required, other than oxygen during initial formation of the chromophore. Therefore, the GFP biomarker holds tremendous promise for elucidation of specific bacterial numbers and their behaviour, colonization, distribution, interaction, and movement in situ in a diversity of environmental sample types. Additionally, mutations have been introduced into the GFP gene in order to produce fluorescence signals with altered properties (Heim et al. 1994, Delagrave et al. 1995, Crameri et 1996, Heim and Tsien 1996). For example, one of the mutants (P4) is a

Recent Advances in Marine Biotechnology, Vol. 8 ◽

10.1201/9781482279986-29 ◽

2003 ◽

pp. 237-237

Keyword(s):

Energy Source ◽

Flow Cytometry ◽

Confocal Laser Scanning Microscopy ◽

Environmental Sample ◽

Laser Scanning ◽

Laser Scanning Microscopy ◽

Confocal Laser Scanning ◽

Confocal Laser ◽

Initial Formation

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Silver Nanoparticles Formation by Jatropha integerrima and LC/MS-QTOF-Based Metabolite Profiling

Nanomaterials ◽

10.3390/nano11092400 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2400

Author(s):

Afrah E. Mohammed ◽

Lamya Ahmed Al-Keridis ◽

Ishrat Rahman ◽

Modhi O. Alotaibi ◽

Rasha Saad Suliman ◽

...

Keyword(s):

Silver Nanoparticles ◽

Laser Scanning ◽

Antibacterial Effect ◽

Therapeutic Potential ◽

Laser Scanning Microscopy ◽

Ultrastructural Changes ◽

Confocal Laser ◽

Synthesis Methods ◽

Tem Analysis ◽

Average Size

The broad application of metal nanoparticles in different fields encourages scientists to find alternatives to conventional synthesis methods to reduce negative environmental impacts. Herein, we described a safe method for preparing silver nanoparticles (J-AgNPs) using Jatropha integerrima leaves extract as a reducing agent and further characterize its physiochemical and pharmacological properties to identify its therapeutic potential as a cytotoxic and antimicrobial agent. The biogenic synthesized J-AgNPs were physiochemically characterized by ultraviolet-visible spectroscopy, dynamic light scattering (DLS), transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy. HPLC-DAD, followed by LC/MS and the Fourier-transform infrared spectroscopy (FTIR), was applied to detect the biomolecules of J. integerrima involved in the fabrication of NPs. Furthermore, J-AgNPs and the ampicillin-nanocomposite conjugate were investigated for their potential antibacterial effects against four clinical isolates. Finally, cytotoxic effects were also investigated against cancer and normal cell lines, and their mechanism was assessed using TEM analysis and confocal laser scanning microscopy (LSM). Ag ions were reduced to spherical J-AgNPs, with a zeta potential of −34.7 mV as well as an average size of 91.2 and 22.8 nm as detected by DLS and TEM, respectively. HPLC GC/MC analysis identified five biomolecules, and FTIR suggested the presence of proteins besides polyphenolic molecules; together, these molecules could be responsible for the reduction and capping processes during NP formation. Additionally, J-AgNPs displayed a strong antibacterial effect, although the ampicillin conjugated form had a very weak antibacterial effect. Furthermore, the NPs caused a reduction in cell viability of all the treated cells by initiating ultrastructural changes and apoptosis, as identified by TEM and LSM analysis. Therefore, J-AgNPs can be formed using the leaf extract from the J. integerrima plant. Furthermore, J-AgNPs may serve as a candidate for further biochemical and pharmacological testing to identify its therapeutic value.

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In Situ Characterization ofNitrospira-Like Nitrite-Oxidizing Bacteria Active in Wastewater Treatment Plants

Applied and Environmental Microbiology ◽

10.1128/aem.67.11.5273-5284.2001 ◽

2001 ◽

Vol 67 (11) ◽

pp. 5273-5284 ◽

Cited By ~ 513

Author(s):

Holger Daims ◽

Jeppe L. Nielsen ◽

Per H. Nielsen ◽

Karl-Heinz Schleifer ◽

Michael Wagner

Keyword(s):

Wastewater Treatment ◽

16S Rrna ◽

Laser Scanning ◽

Wastewater Treatment Plants ◽

Carbon Sources ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Rrna Gene ◽

Phylogenetic Affiliation

ABSTRACT Uncultivated Nitrospira-like bacteria in different biofilm and activated-sludge samples were investigated by cultivation-independent molecular approaches. Initially, the phylogenetic affiliation of Nitrospira-like bacteria in a nitrifying biofilm was determined by 16S rRNA gene sequence analysis. Subsequently, a phylogenetic consensus tree of theNitrospira phylum including all publicly available sequences was constructed. This analysis revealed that the genusNitrospira consists of at least four distinct sublineages. Based on these data, two 16S rRNA-directed oligonucleotide probes specific for the phylum and genus Nitrospira, respectively, were developed and evaluated for suitability for fluorescence in situ hybridization (FISH). The probes were used to investigate the in situ architecture of cell aggregates ofNitrospira-like nitrite oxidizers in wastewater treatment plants by FISH, confocal laser scanning microscopy, and computer-aided three-dimensional visualization. Cavities and a network of cell-free channels inside the Nitrospiramicrocolonies were detected that were water permeable, as demonstrated by fluorescein staining. The uptake of different carbon sources byNitrospira-like bacteria within their natural habitat under different incubation conditions was studied by combined FISH and microautoradiography. Under aerobic conditions, theNitrospira-like bacteria in bioreactor samples took up inorganic carbon (as HCO3 − or as CO2) and pyruvate but not acetate, butyrate, and propionate, suggesting that these bacteria can grow mixotrophically in the presence of pyruvate. In contrast, no uptake by theNitrospira-like bacteria of any of the carbon sources tested was observed under anoxic or anaerobic conditions.

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Monitoring the development of anaerobic biofilms using fluorescent in situ hybridization and confocal laser scanning microscopy

Water Science & Technology ◽

10.2166/wst.2000.0243 ◽

2000 ◽

Vol 41 (12) ◽

pp. 69-77 ◽

Cited By ~ 18

Author(s):

J. C. Araujo ◽

G. Brucha ◽

J. R. Campos ◽

R. F. Vazoller

Keyword(s):

In Situ Hybridization ◽

Confocal Laser Scanning Microscopy ◽

Fluorescent In Situ Hybridization ◽

Laser Scanning ◽

Laser Scanning Microscopy ◽

Confocal Laser Scanning ◽

Scanning Microscopy ◽

Confocal Laser ◽

Anaerobic Consortium

In this study we investigated the development of anaerobic biofilm using a laboratory reactor. We were especially interested in comparing the organization of anaerobic cells (particularly those that are very common in domestic sewage sludge) in a hydrophilic (glass) versus a hydrophobic (polypropylene) surface. Fluorescent in situ hybridization (FISH) with domain and group specific probes directed against 16S ribosomal RNA were used to quantify microbial composition in the biofilm. FISH and confocal laser scanning microscopy (CLSM) were used to elucidate spatial distribution of microbes in the biofilms. Two experiments were carried out, one with pure methanogenic organisms and the other with a microbial anaerobic consortium. The pure methanogen cultures, Methanobacterium formicicum (DSM 1535); Methanosaeta concilli (DSM 3671) and Methanosarcina barkeri (DSM 800) were used to seed the modified Robbins Device (MRD) to allow the development of biofilms on polypropylene and glass surfaces during the 9-days experiment. The results showed that all the three species were colonizing both surfaces after two and nine days of experimental period. In another experiment, with polypropylene coupons only, MRD was seeded with a microbial anaerobic consortium and biofilm formation was studied during 11 days. At the end of this period, the biofilms generated were of uneven thickness with areas of minimal or no surface coverage and areas where the biofilm attained a thickness of 7.0 to 9.0 μm as revealed by CLSM. The results showed that the modified Robbins Device together with the fluorescent in situ hybridization and confocal laser scanning microscopy are suitable tools to study anaerobic biofilm development in different kinds of support materials.

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