摘要:

Studies were undertaken to correlate structure with life cycle in four common species of fungi causing skin disease in man. Hairs naturally infected byMicrosporon audouini, M.felineum, andTrichophyton gypseumand scutula ofAchorion schoenleiniwere placed, without any nutrient medium, in van Tieghem cells at various humidities controlled by osmotic solutions of known vapor pressure. These fungi, which while parasitizing the animal body produce hyphae and thallospores only, were then found to undergo a second period of growth on the detached infected host tissue in moist atmospheres. During this phase they produced all the highly differentiated spore forms previously known only on various media. The aerial hyphae, aleuriospores, fuseaux and spirals produced by suchin situcultures are described in some detail. It is suggested that in nature the saprophytic phase is initiated when the infected tissues fall from the animal body in a moist situation, and that this phase may have significance in the epidemiology of the disease.

ISSN:1923-4287    

DOI:10.1139/cjr34-036

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

This paper records an investigation of cercarial dermatitis, commonly known asswimmer's itchorslough itch, observed on bathers in Clear Lake, Manitoba. The infestation is manifest by the presence of erythematous papules and causes severe itching.As a result of a survey for animal parasites in the lake, and experimental infestations with all forms it has been found that the disease may be caused byCercaria elvaeMiller, a brevifurcate distome cercaria, or by either of two pharyngeal longifurcate distome cercariae,Cercaria wardlein. sp. andCercaria bajkovin. sp. Clinical and pathological notes on the disease are given.

ISSN:1923-4287    

DOI:10.1139/cjr34-037

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

An opisthorchiid Trematode,Parametorchis manitobensisn.sp. is recorded from the livers of sledge dogs from northern Manitoba. A key is given to the known species ofParametorchis. Infection with the trematode produces chronic cirrhosis and anemia, followed by muscular weakness and death. Infection is believed to be contracted by ingestion of metacercariae inCatostomus commersoniiand prophylaxis would consist of the thorough boiling of such fish before use as dog food.

ISSN:1923-4287    

DOI:10.1139/cjr34-038

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

Polyspora lini, the fungus which causes the browning and stem-break disease of flax, was isolated from flax material obtained from Ireland, Sweden, the United States and Canada. Cultural differences in pigmentation and growth characters were exhibited between different strains when grown on potato dextrose, corn meal and prune agars.Saltants arose in the form of sectors from most of the parent cultures. The parent strain from Ireland was particularly prolific in the production of saltants. New strains differing from parental strains and others in cultural characters originated in this way. Many of these in turn produced sectors. Monosporous strains appeared to produce saltations as readily as polysporous strains.Most of the original isolations yielded a special form of the fungus, characterized by the production on all media tested of firm, tough colonies consisting of abundant densely packed mycelia and a relatively sparse development of spores. On the same media the usual form of the fungus develops soft, loose, profusely sporulating colonies. Strains of the new form of the fungus have arisen as saltants either as sectors or as islands in colonies of the ordinary form of the fungus. They have thus far failed to revert to the parental type even after long culture on artificial media or on passage through the host plant.Preliminary pathogenicity tests indicate that the same variety of flax may differ in its reaction to different strains ofPolyspora lini, so that strains of this fungus may differ both in cultural characters and in pathogenicity.

ISSN:1923-4287    

DOI:10.1139/cjr34-039

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

Samples of freshly cut wheat were exposed in freezing chambers, then stook-cured, threshed, and compared with unfrozen check samples, in the seasons 1929, 1930 and 1932, at Edmonton, Alberta. The check samples attained approximately maximum grade and weight per bushel when cut at a stage of maturity represented by a dry matter content ranging in different varieties and seasons from 50 to 60%. The weight per 1000 kernels of Marquis wheat, determined in 1930 only, reached a maximum at the same stage as weight per bushel. Susceptibility to superficial injury by frost continued generally over nearly the whole maturation period. Even 4 degrees of frost (28° F.) frequently caused a cut in grade, while 8, 10 and 14 degrees caused more substantial degradation, often accompanied by some reduction in weight per bushel. Marquis wheat is apparently more susceptible than Garnet, Reward and Red Bobs, to degradation by frost during the maturation period. Grade, being based on external appearance, is more sensitive to frost than are chemical composition and baking quality. Classification of the kernels of Marquis, in 1930, into vitreous, starchy, immature, green, bran frosted and heavily frosted, confirmed the earlier conclusion (2) that only the sound class (vitreous + starchy) has enough relation to grade to be useful as a grading factor. The germination of Garnet was improved by moderate freezing.

ISSN:1923-4287    

DOI:10.1139/cjr34-040

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

Experiments with cereal seeds indicate that the amide groups of reserve seed proteins are more readily removed from the protein during germination than are the other structural units of the protein. No accumulation of amides was found in the non-protein nitrogen of seeds nor in seedlings.

ISSN:1923-4287    

DOI:10.1139/cjr34-041

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

The relation between the physical consistency and chemical composition of a series of blown asphalts from Alberta bitumen has been studied. The amounts of asphaltous acids and anhydrides decrease on blowing, with rise in fusing point of the bitumen. The amounts of oily constituents and resins also decrease but the asphaltene content increases. The molecular weights of the resins increase from 733 to 1012 during blowing. The asphaltenes also show a pronounced increase in molecular weight from 2219 to 4690 Only traces of oxygen are found in the products blown for 6 to 8. 5 hr. at 270 °C; the amount however increases in the later stages of blowing to a maximum of 1.88%. The oily constituents do not contain oxygen, which is distributed mainly in the resin fractions, with smaller amounts occurring in the asphaltene fractions. The sulphur and nitrogen in the bitumen are distributed principally among the resins and asphaltenes. The essential process in blowing bitumen with air is one of condensation by removal of some hydrogen to form water, followed by polymerization, assisted by the sulphur in the bitumen, to products of higher molecular weight. Products similar in composition and physical properties to commercial grades of mineral rubber have been prepared from Alberta bitumen by blowing.

ISSN:1923-4287    

DOI:10.1139/cjr34-042

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

Measurements of the heat capacity of gelatin gels, prepared from ash-free, electric gelatin, have been extended to cover the temperature range between − 180° and 25 °C. and the concentration range from 9 to 100% gelatin. Change in the temperature of the gel above the freezing point is found to be accompanied by a heat effect which has not previously been taken into account in calorimetric measurements on gels and which renders the interpretation of the experimental data uncertain.

ISSN:1923-4287    

DOI:10.1139/cjr34-043

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

A traverse about three miles in length was made with a torsion balance over the lignite deposit at Onakawana in northern Ontario, where it has been outlined by extensive drilling over an area of a few square miles. The drilling shows that it is overlain with 50 to 100 ft. of boulder clay and is imbedded in Cretaceous clay of considerably greater density than the coal. The traverse crossed the seam in three places. At each crossing a definite lowering in the value of gravity was observed. The boundary of the deposit was shown along two parts of the traverse by the large and definite effect on the gradient of gravity. Owing to the fact that as a rule the stations were as far as 100 metres apart and that the drill holes were usually 1000 ft. or more from one another, uncertainty exists at some stations regarding the respective gravitational effects of variations of the coal seam, on the one hand, and possible irregularities in the boulder clay, on the other. The results indicate that the torsion balance may be of use in outlining such deposits as the Onakawana lignite. A better estimate of the value of the instrument could be made if it had been possible to make a more definite test of the effect of irregularities in the boulder clay.Numerous magnetometer readings over and in the vicinity of the coal seam showed so little variation that there appears to be little hope that this instrument would be of use in prospecting for the coal, at least in so far as the immediate boundaries are concerned.A preliminary survey of the Grand Rapids siderite deposit on the Mattagami river was made with vertical and horizontal magnetometers. The iron occurs in limestone which, except at the river, is buried beneath 50 ft. or more of drift. The anomaly produced by the iron does not apparently exceed 100 γ and is complicated by a larger and more regional anomaly which makes definite interpretation of the results difficult. A more detailed survey might be productive of useful results. Magnetometric traverses were made along the rivers from Grand Rapids to James Bay and from Williams Island in the Abitibi to its mouth. A similar magnetic anomaly to that at Grand Rapids was observed at Williams Island. There is quite a marked magnetic anomaly at Moose Factory.

ISSN:1923-4287    

DOI:10.1139/cjr34-044

出版商:NRC Research Press    

年代:1934

数据来源: NRC