scholarly journals Intermediate type-I superconductors in the mesoscopic scale

2021 ◽  
Vol 103 (1) ◽  
Author(s):  
Leonardo R. Cadorim ◽  
Antonio R. de C. Romaguera ◽  
Isaías G. de Oliveira ◽  
Rodolpho R. Gomes ◽  
Mauro M. Doria ◽  
...  
1942 ◽  
Vol 42 (1) ◽  
pp. 55-98 ◽  
Author(s):  
C. G. Batty-Smith

1. A historical survey is given of work upon the Eijkman method.2. A total of 104 water samples were examined by methods I and III. These yielded 602 cultures obtained from the 44 and 37° C. presumptive series, and of these 357 were 44° C.-positive. The only types capable of fermenting lactose at 44° C. wereBact. colitype I and Irregular type II, with the addition of three cultures of intermediate type I and two ofaerogenestype I.3. The relative efficiencies in the detection ofBact. coliof the 44° C. method by direct inoculation and of the 37° C. presumptive test with plating and differentiation were compared. Out of 104 samples, sixty-eight were shown to contain faecalBact. coli, and in 19% of these the 44° C. method detectedBact. coliwhen it was not recovered at 37° C. The converse was true in only 13% of samples.4. The results obtained by other workers in regard to the specificity of incubation at 44° C. and to the various methods hitherto proposed for employing it have been collected and discussed; technical advantages and disadvantages have also been considered.5. It is concluded: (1) That false positives at 44° C. are a negligible quantity for practical purposes. (2) That the best all-round method to use is Wilson's method IV. (3) That 48 hr. incubation should be given, but that 24 hr. is sufficient when rapidity is desired. (4) That the test should be officially recognized and standards laid down for use with it.6. Cellobiose was found to be inferior to citrate for the identification of the I.A.C. group.


Clay Minerals ◽  
2017 ◽  
Vol 52 (2) ◽  
pp. 191-202 ◽  
Author(s):  
Muazzez Çelik Karakaya ◽  
Necati Karakaya ◽  
Fuat Yavuz

AbstractThis study focused on the mineralogical and physico-chemical properties of heulandite/clinoptilolite (Heu/Cpt)-rich zeolitic tuffs SE of Ankara (Turkey) and evaluated their potential for use as adsorbents. The main Heu/Cpt minerals correspond to the intermediate type and the Cpt-type of the heulandite series. Minor chabazite, erionite and rarely analcime and accessory feldspars, mica, smectite, and quartz were also detected. Three types of Heu were recognized according to their thermal behaviour. Cpt (type-III Heu) was thermally stable at 600°C, whereas type-I Heu collapsed and type-II Heu partially collapsed. The Si/Al ratios of the Hul/Cpt ranged from 3.54 to 5.03, the Γ parameter (Γ = Ca/Al + 0.115*Al) varied between 0.78 and 1.85 and Al + Fe3+varied between 6.27 and 8.00. The Na, K and Ca contents of Heu/Cpt varied widely and the Heu had an intermediate composition between types II and III. The Mg + Ca content is greater than the Na + K content in Heu-type II and smaller in Heu-type III zeolites. The BET surface area and the pore-size of the samples varied between 10.15 and 194.27 m2/g, and between 1.41 and 12.42 nm, respectively. The N2adsorption and desorption isotherms were comparable, but the adsorption/desorption capacity is greater in type III than in type II Heu zeolites. The cation exchange capacities of the Heu/Cpt-rich samples ranged from 185 to 280 meq/100 g.


1945 ◽  
Vol 44 (2) ◽  
pp. 109-115 ◽  
Author(s):  
C. B. Taylor

1. A study has been made of different types of coliform bacteria with particular reference to (a) their ability to ferment lactose in MacConkey broth at different temperatures, and (b) the effect of using different temperatures of incubation for the indol, methyl-red, V.P., and citrate tests.2. It was found that 97% of the cultures ofBact. coli(indol positive, methyl-red positive, V.P. negative, citrate negative) examined could ferment lactose with production of acid and gas between 40 and 44° C. The number was not appreciably reduced at 45° C. but was markedly reduced at 46° C. 28% of the cultures ofBact. coli(indol negative, methyl-red positive, V.P. negative, citrate negative) and 15% ofBact. aerogenes(indol negative, methyl-red negative, V.P. positive, citrate positive) were found to be positive at 44° C.3. The adoption of a temperature of incubation of 30°C. for the V.P. test as advocated by Levine (1941) and the use of O'Meara's test showed that many cultures previously regarded as unable to produce acetylmethylcarbinol were in fact able to do so. Employing a temperature of 30°C. for 5, or in some cases 7, days for the methyl-red test, it was found that with nearly all the cultures tested there was an inverse correlation between the results of the methyl-red test and those of the V.P. test. With these modifications in technique some cultures originally designated as Intermediate type I were found to have reactions corresponding with those ofBact. aerogenestype I. Similarly, many cultures originally classified as Intermediate type II should have been typed asBact. aerogenestype II.4. It was found that all cultures of Intermediate type I classified as such by the new technique were incapable of using the nitrogen of uric acid for growth, but that the majority produced hydrogen sulphide. Cultures ofBact. aerogenestype II, on the other hand, grew well in uric acid medium, but produced no hydrogen sulphide.The investigation described in this paper was carried out by the Freshwater Biological Association, as part of the programme of the Water Pollution Research Board of the Department of Scientific and Industrial Research. The paper is published by permission of the Department.


Parasitology ◽  
1993 ◽  
Vol 107 (3) ◽  
pp. 297-309 ◽  
Author(s):  
A. W. Stitt ◽  
I. Fairweather

SummaryThe effect of the microtubule inhibitors coichicine (1×10−3 M) and tubulozole-C(1×10−6 M) on the ultrastructure of adult Fasciola hepatica has been determined in vitro by transmission electron microscopy (TEM), using both intact flukes and tissue-slice material. With colchicine treatment, the apical membrane of the tegument became increasingly convoluted and blebbed, while accumulations of T1 secretory bodies occurred in the basal region of the syncytium, leading to progressively fewer secretory bodies in the syncytium. In the tegumental cells there were distinct accumulations of T1 secretory bodies around the Golgi complexes, which remained active for up to 12 h incubation. Tubulozole-treated flukes showed more severe effects, with initial accumulations of secretory bodies, both at the tegumental apex and base. This was followed in the later time-periods by the sloughing of the tegumental syncytium. In the underlying tegumental cells, the granular endoplasmic reticulum (GER) cisternae were swollen and disrupted, becoming concentrated around the nucleus. The Golgi complexes were dispersed to the periphery of the cells and gradually disappeared from the cytoplasm. After treatment with both drugs, the cell population in the vitelline follicles was altered, with an abnormally large proportion of stem cells and relatively few intermediate type I cells. The nurse cell cytoplasm became fragmented and was no longer in contact with the vitelline cells, while the shell globule clusters within the intermediate type 2 and mature cells were loosely packed. In the mature vitelline cells, ‘yolk’ globules and glycogen deposits became fewer than normal and lipid droplets were observed. The results are discussed in relation to the different modes of action of the two drugs and potential significance of this to anthelmintic (benzimidazole) therapy.


Author(s):  
I. Russo ◽  
J. Saby ◽  
J. Russo

It has been previously demonstrated that DMBA-induced rat mammary carcinoma originates in the terminal end bud (TEB) of the mammary gland by proliferation of intermediate type cells (1). The earliest lesion identified is the intraductal proliferation (IDP), which gives rise to intraductal carcinomas. These evolve to cribriform, papillary and comedo types (2). In the present work, we report the ultrastructural changes that take place in the IDP for the formation of a cribriform pattern.Fifty-five-day-old Sprague Dawley virgin female rats were inoculated intra- gastrically with 20 mg 7,12-dimethylbenz(a)anthracene (DMBA) in 1 ml sesame oil. Non-inoculated, age-matched females were used as controls. Mammary glands from both control and experimental rats were removed weekly from the time of inoculation until 86 days post-inoculation. The glands were fixed and processed for electron microscopy (2).The first change observed in IDP's was the widening of intercellular spaces and the secretion of an electron dense material into these spaces (Fig. 1).


Author(s):  
Ronald S. Weinstein ◽  
N. Scott McNutt

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.


Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
I. E. Stratmann ◽  
C. Ezrin

Surgically removed human pituitary glands as well as pituitary tumors fixed in glutaraldehyde, postfixed in osmium tetroxide, embedded in epon resin, stained with uranyl acetate and lead citrate have been investigated by electron microscopy in order to correlate ultrastructure with functional activity. In the course of this study two distinct types of microfilaments have been identified in the cytoplasm of adenohypophysiocytes.Type I microfilaments (Fig. 1) were found in the cytoplasm of anterior lobe cells of five female subjects with disseminated mammary cancer and two patients with severe diabetes mellitus. The breast cancer patients were treated pre-operatively for various periods of time with different doses of oxysteroids. The microfilaments had an average diameter of JO A, formed parallel bundles, were scattered irregularly in the cytoplasm and were frequently located in the perikaryon. They were not membrane-bound and failed to show any periodicity.


Author(s):  
W. Jurecka ◽  
W. Gebhart ◽  
H. Lassmann

Diagnosis of metabolic storage disease can be established by the determination of enzymes or storage material in blood, urine, or several tissues or by clinical parameters. Identification of the accumulated storage products is possible by biochemical analysis of isolated material, by histochemical demonstration in sections, or by ultrastructural demonstration of typical inclusion bodies. In order to determine the significance of such inclusions in human skin biopsies several types of metabolic storage disease were investigated. The following results were obtained.In MPS type I (Pfaundler-Hurler-Syndrome), type II (Hunter-Syndrome), and type V (Ullrich-Scheie-Syndrome) mainly “empty” vacuoles were found in skin fibroblasts, in Schwann cells, keratinocytes and macrophages (Dorfmann and Matalon 1972). In addition, prominent vacuolisation was found in eccrine sweat glands. The storage material could be preserved in part by fixation with cetylpyridiniumchloride and was also present within fibroblasts grown in tissue culture.


Author(s):  
E.M. Kuhn ◽  
K.D. Marenus ◽  
M. Beer

Fibers composed of different types of collagen cannot be differentiated by conventional electron microscopic stains. We are developing staining procedures aimed at identifying collagen fibers of different types.Pt(Gly-L-Met)Cl binds specifically to sulfur-containing amino acids. Different collagens have methionine (met) residues at somewhat different positions. A good correspondence has been reported between known met positions and Pt(GLM) bands in rat Type I SLS (collagen aggregates in which molecules lie adjacent to each other in exact register). We have confirmed this relationship in Type III collagen SLS (Fig. 1).


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