Preliminary investigation and dynamic analysis of a multiphase ice-rock avalanche on July 5, 2021, in the upper Naltar valley, Gilgit, Pakistan

Gaps between mating parts of large industrial components are required for assembly and to allow for free thermal or pressure growth. However, the gaps should not be so large as to invalidate linear analysis assumptions for dynamic loadings. Large components may have locations where there are tightly controlled dimensions to accommodate mating parts. At these locations there are specified gaps that are crucial in manufacturing and installing the parts and assemblies. These gaps are strategically determined to provide reasonable assurance that the components can be economically manufactured and assembled without violating structural and functional requirements for the components. In general, large gaps are desirable to facilitate assembly. Small gaps may be necessary to ensure the validity of linear-elastic dynamic analysis and to control leakage. Industry practices for 1/8-inch to 1/4-inch gaps are cited for pipes supported by box frames. The justification for the use of these gap sizes is not readily available in the open literature. This paper presents the results of a preliminary investigation into the effect of gaps on the dynamic analysis of internal components of heavy pressure vessels. Parameteric analytical studies using simple finite element beam models show that loads and stresses increase with gap size. For example, using the results for 1/16-inch gap as the basis, the maximum stresses and loads for a 1/8-inch gap increase by a maximum of approximately 30%.

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Surface ultrastructure of danazol treated rat endometrium: A SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007641x ◽

1983 ◽

Vol 41 ◽

pp. 556-557

Author(s):

R.P. Apkarian ◽

J.S. Sanfilippo

Keyword(s):

Cross Sections ◽

Reproductive Tract ◽

Preliminary Investigation ◽

Breast Disease ◽

Distal Segment ◽

Uterine Horn ◽

Female Reproductive Tract ◽

Ultrastructural Changes ◽

Cycle Phase ◽

Sprague Dawley

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.

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A Comparison of the Ultrastructural Morphology of Hepatic Necrosis in BDF1 Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099350 ◽

1981 ◽

Vol 39 ◽

pp. 586-587

Author(s):

Becky Jackson

Keyword(s):

Endoplasmic Reticulum ◽

Smooth Endoplasmic Reticulum ◽

Preliminary Investigation ◽

Hepatic Necrosis ◽

Hepatic Tissue ◽

Pronounced Increase ◽

Glycogen Store ◽

Ultrastructural Morphology ◽

Mitochondrial Integrity ◽

Glycogen Stores

Preliminary investigation has indicated similarity in hepatic ultrastructural morphology in nutritional deprivation, and cyanide induced hepatic necrosis. Analysis of hepatic tissue has indicated disruption of intracellular membranes, specifically, reduction in rough endoplasmic reticulum (RER) mitochondrial integrity, and glycogen stores. An increase in smooth endoplasmic reticulum (SER) portion was observed.To further investigate the apparent equivalence of necrotic morphology, ultrastructura1ly, BDF1 mice were subjected to senescence, nutritional deprevation, potassium cyanide (KCN) induced toxemia, and acetaminophen induced toxemia. Controls were utilized to ellucidate non-necrotic hepatocellular normals. U1trastructura1 investigation of controls (Fig. 1) shows densely granular RER, abundant glycogen stores, and morphologically normal mitochondria. Subjects with acetaminophen induced necrosis exhibit reduced normal RER with increased levels of dialated, vesicular RER in apparent conversion to SER (Fig. 2), loss of mitochondrial integrity, and glycogen store reduction. Senescent subjects exhibit a pronounced increase in SER and loss of glycogen store. (Fig. 3). Investigation of the senescent SER at high magnification (Fig. 5) indicates that the SER is arising from degranulating and vesiculating RER.

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Ultrastructural Effects of Acute Kepone Treatment in Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009141x ◽

1976 ◽

Vol 34 ◽

pp. 286-287

Author(s):

Richard L. Klein ◽

Åsa K. Thureson-Klein ◽

Harihara M. Mehendale

Keyword(s):

Neurological Disorders ◽

Corn Oil ◽

Preliminary Investigation ◽

Reproductive Capacity ◽

Ultrastructural Changes ◽

Lipid Deposition ◽

Severe Toxicity ◽

Sprague Dawley ◽

Ether Anesthesia ◽

Sprague Dawley Rats

KeponeR (decachlorooctahydro-1,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one) is an insecticide effective against ants and roaches. It can cause severe toxicity in fishes, birds, rodents and man. Prominent effects include hepatic lipid deposition and hypertrophy, impairment of reproductive capacity and neurological disorders. Mitochondrial oligomycin-sensitive Mg2+-ATPase is also inhibited. The present study is a preliminary investigation of tissue ultrastructural changes accompanying physiological signs of acute toxicity, which after two days treatment include: pronounced hypersensitivity and tremor, various degrees of anorexia and adipsia, and decreased weight gain.Three different series of adult male Sprague-Dawley rats (Charles River or CD-I) were treated by intubation with Kepone in corn oil at a dose of 50 mg per kg for 3 successive days or at 200 ppm in food for 8 days. After ether anesthesia, rats were immediately perfused via a cannula in the left ventricle with 4% p-formaldehyde and 0.5% glutaraldehyde in Millonig's phosphate buffer at pH 7.2 for 20-30 min at 22°C.

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