scholarly journals The search for a reliable mounting medium for Recent ‘live’ foraminifera

1991 ◽  
Vol 9 (2) ◽  
pp. 172-172 ◽  
Author(s):  
C. Maybury ◽  
L. Morrison ◽  
V. Stewart
Keyword(s):  
Refractive Index ◽  
Microscopical Examination ◽  
Insufficient Time ◽  
Light Microscopical Examination

Abstract. There is no suitable mounting medium for the longterm storage of Recent, ‘live’ foraminifera. Glycerol has been used for this purpose since the last century, but its properties do not meet our requirements (see below). We therefore began a series of trials in order to find the ‘perfect’ mountant. The inception of this ‘Micropalaeontological Notebook’ provides a timely opportunity to highlight the results of our experiments and to elicit a response from the readership to facilitate our search.In choosing mounting media for experiment it was first necessary to detail our requirements. The latter are as follows: the medium must be clear and possess a refractive index (nD:) close or equal to that of glass. The nD of the mounted specimens should differ from that of the mountant or they will be invisible. It should function as a permanent mount, fixing specimens in a position suitable for light microscopical examination. It should not form aggregations or induce overlap of specimens and should permit easy relocation of small organisms (i.e., fixing them so that their co-ordinates can be read with an England Finder) It should neither be messy nor aspirate air and should not contract, thereby crushing delicate specimens. The mountant must be treated to inhibit bacterial and fungal growths. It must be relatively inexpensive and quick to prepare and must not solidify too rapidly, leaving insufficient time to position specimens. Since the specimens are ‘live’ it is important that the protoplasmic contents of the cell and the mountant are isotonic. Similarly, . . .

scholarly journals The search for a reliable mounting medium for Recent ‘live’ foraminifera

1991 ◽  
Vol 10 (1) ◽  
pp. 16-21 ◽  
Author(s):  
C. Maybury ◽  
L. Morrison ◽  
V. Stewart
Keyword(s):  
Refractive Index ◽  
Microscopical Examination ◽  
Long Term Storage ◽  
Insufficient Time ◽  
Term Storage ◽  
Light Microscopical Examination

Abstract. There is no suitable mounting medium for the long term storage of Recent ‘live’ foraminifera. Glycerol has been used for this purpose since the last century, but its properties do not meet our requirements (see below). We therefore began a series of trials in order to find the ‘perfect’ mountant. The inception of this “Micropalaeontological Notebook” provides a timely opportunity to highlight the results of our experiments and to elicit a response from the readership to facilitate our search.In choosing mounting media for experiment it was first necessary to detail our requirements. The latter are as follows: the medium must be clear and possess a refractive index (nD) close or equal to that of glass. The nD of the mounted specimens should differ from that of the mountant or they will be invisible. It should function as a permanent mount, fixing specimens in a position suitable for light microscopical examination. It should not form aggregations or induce overlap of specimens and should permit easy relocation of small organisms (i.e., fixing them so that their co-ordinates can be read with an England Finder). It should neither be messy nor aspirate air and should not contract, thereby crushing delicate specimens. The mountant must be treated to inhibit bacterial and fungal growths. It must be relatively inexpensive and quick to prepare and must not solidify too rapidly, leaving insufficient time to position specimens. Since the specimens are ‘live’ it is important that the protoplasmic contents of the cell auld the mountant are. . .

The Toxic Effects of Two Dental Materials on Human Buccal Epithelium In Vitro and Monkey Buccal Epithelium In Vivo

1987 ◽  
Vol 14 (3) ◽  
pp. 166-167
Author(s):  
D. Arenholt-Bindslev ◽  
P. Hørsted-Bindslev ◽  
H.P. Philipsen
Keyword(s):  
Dental Materials ◽  
Microscopical Examination ◽  
Buccal Epithelium ◽  
Cytotoxic Effects ◽  
Buccal Epithelial Cells ◽  
Toxicity In Vitro ◽  
Toxic Reactions ◽  
Light Microscopical Examination

The aim of the present study was to compare the toxicity in vitro with the toxicity in vivo of two commercial chemicals marketed for use in the oral cavity (GLUMA BondR and 3M Etching LiquidR). Confluent cultures of human buccal epithelial cells were exposed to graded concentrations of GLUMA Bond or 3M Etching Liquid for 5 minutes. The cytotoxic effects induced by this treatment were observed (cytomorphology, proliferation rate). In vivo, monkey buccal epithelium was exposed to GLUMA Bond or 3M Etching Liquid for 5 minutes. Biopsies were taken after 24 hours, and the buccal epithelium processed for light microscopical examination. In both models, the toxic reactions to GLUMA Bond were far more extensive than those caused by 3M Etching Liquid.

The urinary sediment beyond light microscopical examination

2006 ◽  
Vol 21 (6) ◽  
pp. 1482-1485 ◽  
Author(s):  
G. Colucci ◽  
J. Floege ◽  
F. P. Schena
Keyword(s):  
Microscopical Examination ◽  
Urinary Sediment ◽  
Light Microscopical Examination

scholarly journals SELECTIVE ABORTION OF TWO NONSISTER NUCLEI IN A DEVELOPING ASCUS OF THE hfd1—1 MUTANT IN SACCHAROMYCES CEREVISIAE

Genetics ◽  
1981 ◽  
Vol 99 (2) ◽  
pp. 197-209
Author(s):  
Susumu Okamoto ◽  
Tetsuo Iino
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mutant Strain ◽  
Recessive Mutation ◽  
Microscopical Examination ◽  
Wild Type ◽  
Selective Abortion ◽  
Dyad Analysis ◽  
Mutant Cells ◽  
Type Strains ◽  
Light Microscopical Examination

ABSTRACT A recessive mutation, hfd1—1, in strain SOS4 of Saccharomyces cerevisiae leads the mutant cells to produce predominantly two-spored asci. Light microscopical examination of Giemsastained cells revealed no significant differences in the meiotic figures between mutant and wild-type strains. However, only two of the four meiotic products in a developing ascus matured to ascospores in SOS4. Dyad analysis was carried out on an hfd1-1 mutant strain heterozygous for three markers, asp5, gal1 and arg4, which are closely linked to their centromeres, and for his4, which is loosely linked to its centromere. The twospored asci produced by the hfd1—1 mutant segregated dominant (+) and recessive (-) alleles of each marker in a 1:1 ratio; they generally contained one + and one - spore for any given marker. The occurrence of rare dyads with two + or two - spores can be explained quantitatively by recombination between the marker and its centromere. From the results of these cytological and genetical analyses, we infer that, in the mutant strain, one genome set is partitioned to each of the four second-meiotic division poles, but only two nonsister genomes are incorporated into mature spores. Thus, the hfd1—1 mutation in SOS4 blocks incorporation of two nonsister nuclei into mature ascospores, but does not block enclosure of the remaining two nonsister nuclei.

TEM characterization of proton-exchanged LiNbO3 optical waveguides

1986 ◽  
Vol 44 ◽  
pp. 480-481
Author(s):  
W. E. Lee
Keyword(s):  
Refractive Index ◽  
Benzoic Acid ◽  
Optical Waveguides ◽  
Total Internal Reflection ◽  
Index Of Refraction ◽  
Optical Measurements ◽  
Lithium Ions ◽  
Wide Channel ◽  
Tem Characterization

An optical waveguide consists of a several-micron wide channel with a slightly different index of refraction than the host substrate; light can be trapped in the channel by total internal reflection.Optical waveguides can be formed from single-crystal LiNbO3 using the proton exhange technique. In this technique, polished specimens are masked with polycrystal1ine chromium in such a way as to leave 3-13 μm wide channels. These are held in benzoic acid at 249°C for 5 minutes allowing protons to exchange for lithium ions within the channels causing an increase in the refractive index of the channel and creating the waveguide. Unfortunately, optical measurements often reveal a loss in waveguiding ability up to several weeks after exchange.

Correlation of γ-radioactivity and Scanning Electron Microscopy in measurement of retention of 111Indium-labeled canine endothelial cells on synthetic vascular grafts

1989 ◽  
Vol 47 ◽  
pp. 886-887
Author(s):  
E.J. Prendiville ◽  
S. Laliberté Verdon ◽  
K. E. Gould ◽  
K. Ramberg ◽  
R. J. Connolly ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ex Vivo ◽  
Vascular Grafts ◽  
Retention Data ◽  
Vascular Prostheses ◽  
Group 4 ◽  
Human Fibronectin ◽  
Insufficient Time ◽  
Group 3 ◽  
Group 2

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.

Light microscopy of ceramics

1993 ◽  
Vol 51 ◽  
pp. 908-909
Author(s):  
Walter C. McCrone
Keyword(s):  
Refractive Index ◽  
Light Microscopy ◽  
Light Microscope ◽  
Polarized Light ◽  
Refractive Indices ◽  
Complete Coverage ◽  
The Subject ◽  
Lower Refractive Index

An excellent chapter on this subject by V.D. Fréchette appeared in a book edited by L.L. Hench and R.W. Gould in 1971 (1). That chapter with the references cited there provides a very complete coverage of the subject. I will add a more complete coverage of an important polarized light microscope (PLM) technique developed more recently (2). Dispersion staining is based on refractive index and its variation with wavelength (dispersion of index). A particle of, say almandite, a garnet, has refractive indices of nF = 1.789 nm, nD = 1.780 nm and nC = 1.775 nm. A Cargille refractive index liquid having nD = 1.780 nm will have nF = 1.810 and nC = 1.768 nm. Almandite grains will disappear in that liquid when observed with a beam of 589 nm light (D-line), but it will have a lower refractive index than that liquid with 486 nm light (F-line), and a higher index than that liquid with 656 nm light (C-line).

Expressed Emotion in the Client-Professional Dyad

2004 ◽  
Vol 20 (4) ◽  
pp. 237-246 ◽  
Author(s):  
G. Van Humbeeck ◽  
Ch. Van Audenhove ◽  
G. Storms ◽  
M. De Hert ◽  
G. Pieters ◽  
...  
Keyword(s):  
Therapeutic Relationship ◽  
Correlation Matrix ◽  
Concurrent Validity ◽  
Positive Relationship ◽  
Expressed Emotion ◽  
Family Interview ◽  
Insufficient Time ◽  
Perceived Criticism

Summary: Background: This article reports on a study of the concurrent validity between the standard expressed emotion instrument, the Camberwell Family Interview (CFI), and two alternative EE measures, the Level of Expressed Emotion (LEE) and the Perceived Criticism Scale (PCS). Methods: The research sample consisted of 56 schizophrenic clients, who were residing in sheltered residences, and 56 professionals. Results: Based on the results of the correlation matrix between all the subscales of the instruments, a significantly positive relationship was found between the criticism scale of the CFI, the total score of the LEE, and the client version of the PCS. These correlations, however, were rather weak, which implies that the three instruments have little in common with each other. The professionals' version of the PCS does not appear to be an EE instrument. Conclusions: The results suggest that the CFI still remains the best instrument for assessing EE in a therapeutic relationship (between a professional and a client). If there is insufficient time to administer the CFI, then the client version of the PCS and the LEE can be used with the qualification that the PCS and LEE also measure other aspects and thus cannot completely replace the CFI. Nevertheless, the research indicates that asking the clients would seem to provide a better indication of the level of the professionals' criticism rather than asking the professionals themselves directly.

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