Morphological aspects of chromosome spindle fibres inMesostoma: ?microtubular fir-tree? structures and microtubule association with kinetochores and chromatin

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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Electron Microscopy of Mycoplasma Pneumoniae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065341 ◽

1971 ◽

Vol 29 ◽

pp. 258-259 ◽

Cited By ~ 1

Author(s):

E. S. Boatman ◽

G. E. Kenny

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Growth Phase ◽

Hela Cells ◽

Sulfonic Acid ◽

Gamma Globulin ◽

Horse Serum ◽

Morphological Aspects ◽

The Family

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.

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Experimental Characterization of the Reliability of 3-Terminal Dual-Damascene Copper Interconnect Trees

MRS Proceedings ◽

10.1557/proc-716-b8.13 ◽

2002 ◽

Vol 716 ◽

Cited By ~ 4

Author(s):

C. L. Gan ◽

C. V. Thompson ◽

K. L. Pey ◽

W. K. Choi ◽

F. Wei ◽

...

Keyword(s):

Stress Conditions ◽

Experimental Characterization ◽

Contact Lines ◽

Tree Structures ◽

Similar Test ◽

Dual Damascene ◽

Copper Interconnect ◽

Test Conditions

AbstractElectromigration experiments have been carried out on simple Cu dual-damascene interconnect tree structures consisting of straight via-to-via (or contact-to-contact) lines with an extra via in the middle of the line. As with Al-based interconnects, the reliability of a segment in this tree strongly depends on the stress conditions of the connected segment. Beyond this, there are important differences in the results obtained under similar test conditions for Al-based and Cu-based interconnect trees. These differences are thought to be associated with variations in the architectural schemes of the two metallizations. The absence of a conducting electromigrationresistant overlayer in Cu technology, and the possibility of liner rupture at stressed vias lead to significant differences in tree reliabilities in Cu compared to Al.

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MORPHOLOGICAL ASPECTS OF SURGICAL TREATMENT IN PATIENTS WITH DRUG RESISTANT PULMONARY TUBERCULOSIS

Ukrainian Pulmonology Journal ◽

10.31215/2306-4927-2018-99-1-59 ◽

2018 ◽

Vol 99 (1) ◽

pp. 59-64

Author(s):

O.V. Khmel ◽

◽

I.A. Kalabukha ◽

I.V. Liskina

Keyword(s):

Surgical Treatment ◽

Pulmonary Tuberculosis ◽

Drug Resistant ◽

Morphological Aspects

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Diseases Prevention by Water Defluoridation Using Hydrotalcites as Decontaminant Materials

Revista de Chimie ◽

10.37358/rc.17.1.5412 ◽

2017 ◽

Vol 68 (1) ◽

pp. 168-171 ◽

Cited By ~ 2

Author(s):

Letitia Doina Duceac ◽

Cristina Elena Dobre ◽

Ioana Pavaleanu ◽

Gabriela Calin ◽

Simona Nichitus ◽

...

Keyword(s):

Dental Fluorosis ◽

Precipitation Method ◽

Original Structure ◽

Fluoride Removal ◽

Major Goal ◽

Bone Stiffness ◽

Morphological Aspects ◽

Adsorption Capacities ◽

Interlayer Structure ◽

Co Precipitation

Preventing diseases is deemed to be the major goal of our century especially when an excessive fluoride in drinking water can cause dental fluorosis, bone stiffness, rheumatism and skeletal fluorosis. Fluoride uptake from groundwater implies a worldwide multidisciplinary effort in order to develop renewable, cheap, human friendly materials. Among other materials, hydrotalcites could be good candidates for an efficient fluoride removal from water due to their adsorption, anion exchange and reconstruction properties. These nanostructured materials were synthesized using co-precipitation method in controlled conditions. Presence of anions in the interlayer structure and morphological aspects were performed by FTIR and SEM techniques. Thermal treatment of hydrotalcites showed good adsorption capacities for water defluoridation mostly due to their tendency to restore the original structure.

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