LIX. On the measurement of the power supplied to the primary coil of a transformer

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Chemical investigations of the "Gifblaar" Dichapetalum cymosum (Hook) Engl. I

Although the investigations recorded in this paper have not resulted in the isolation of the toxic principle of the Gifblaar, Dichapetalum cymosum in a state of chemical purity, it is felt that certain valuable information has been obtained relative to the nature of this toxin. In addition, some interesting substances have been isolated from the plant in the course of chemical manipulations. These include: (1) A catechol tannin. (2) A yellow colouring matter, shown to be a methylpentoside, yielding rhamnose on hydrolysis. (3) A histidine-like base. (4) A base probably identical with choline. (5) The alkaloid trigonelline, the methyl-betaine of nicotinic acid. Various specialised methods were tried for the purification of the toxin, including: (1) Dialysis. (2) Ultrafiltration under pressures up to 80 atmospheres of nitrogen. (3) High-vacuum distillation and sublimation. (4) Continuous extraction with butyl alcohol, etc. Certain other chemical operations led to the conclusion that the following groups are definitely absent from the toxin molecule: Carboxyl –COOH; Ketonic >CO; Aldehyde –CHO; Hydroxyl –OH; Amino –NH₂; Imino >NH. The active principle almost certainly contains nitrogen and it is suggested that this may be included in some cyclic structure. It may possibly occur as in tertiary bases but the molecule, as a whole, does not evince basic characters. Preparations, still highly toxic to rabbits, have been prepared containing no protein, amino-acid, or carbohydrate material, impurities which had not before been successfully removed. The chemical stability or inertness of the toxic substance is very remarkable in view of its pronounced physiological action. Thus, it resists boiling for one hour with 1 per cent. sulphuric acid or 1 per cent. sodium hydroxide solutions; it is not oxidised by potassium permanganate or by hydrogen peroxide in the cold and it is thermostable. In view of this stability and the absence of any substance known to combine with or precipitate the toxin, the hope of finding any specific prophylactic or curative substance for use in Gifblaar poisoning becomes very remote indeed.The articles have been scanned in colour with a HP Scanjet 5590;300dpi. adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Recent advances in the chemistry of the plasma proteins and their complexes

This is a review and, as stated in the introduction, the author confines himself to certain aspects of the subject only - the modern conception of the individual identities and interrelationships of the serum proteins apart from fibrinogen. Recent advances in the chemistry of the complexes which these proteins are known to form with lipoid and carbohydrate materials are discussed. Commencing with the proteins of the serum, the author goes on to discuss the albumin and globulin fractions, the behaviour of the serum lipoids and, finally, the "bound sugar" of the blood and protein carbohydrate complexes, to the study of which he has himself contributed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Psilocaulon absimile N.E.Br. as a stock poison : II. Isolation of the toxic alkaloidal constituent and its identification as piperidine hydrochloride

The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.The alkaloid present in Psilocaulon articulatum, N.E.Br. has been isolated and identified as Piperidine. It occurs in plant in part as the hydrochloride and is present to the extent of approximately 4.5 per cent. Of the dry weight. Piperidine picrolonate has been prepared and described. It crystallises in golden-yellow hexagonal tables with M.P. 232-234°. The melting point of piperidine picrate is recorded as 149-149.5° and that of the gold salt as 173-176°. Piperidine has not hitherto been found as a naturally occurring alkaloid in plants, although it is component of certain important alkaloids such as, for example, piperine and coniine. Only one other alkaloid has been reported in the family Aizoaceae, the alkaloid “Mesembrine” which was not definitely characterised as a pure substance. Death due to acute poisoning following the ingestion of Psilocaulon absimile by grazing stock is to be attributed in large measure to the action of the alkaloid. Chronic poisoning is almost certainly due to the effects of the large quantity of oxalic acid which the plant also contains. The toxicological effects upon rabbits and frogs of preparations of piperidine hydrochloride obtained from the plant are briefly described in the present paper. Good quality piperidine is only obtainable commercially at a high price, about £6.8s. per lb., and it is suggested that the plant Psilocaulon absimile, which is widely distributed in the Union and useless as a fodder, might serve as cheap alternative source for the manufacture of this material

Let women take the lead: Insights from the UK defense industry

We discuss how gender diversity in the workplace is managed (or not) within a non-traditional environment, specifically a UK defense company, aiming to gain an understanding of the impact on female employees. We argue that there are still remnants of bias – both conscious and unconscious – within the workplace, and some of the female participants felt that discrimination is embedded in the corporate culture. Our study revealed that there are currently no female role models within the senior ranks; and few women had progressed into middle management. We position the study within debates around diversity and inclusion and human capacity development in the UK defense sector in general, and specifically the armed forces. We also show how issues of equality are addressed in diverse ways, through legislation and gender quotas, and emphasize why achieving and safeguarding gender equality is important to practicing managers

Chemical studies upon the vermeerbos, Geigeria aspera Harv. I. Isolation of a bitter principle "geigerin”

l. There has been isolated from toxic consignments of Geigeria aspera, Harv. a neutral lactonic bitter principle to which the name Geigerin has been assigned. This substance, though not the true toxic principle, would appear to be not altogether devoid of pharmacological properties. 2. Geigerin has the formula C₁₅H₂₀O₄ and crystallises from water or moist organic solvents with 1 molecule of water of crystallisation. It exhibits isomerism, the melting points of the two varieties, when anhydrous, being 169° and 189° but preliminary softening with liberation of water from the hydrated prisms is observed at about 68° and 76° respectively. No matter which isomer is used, the same optical activity is exhibited in the same solvent. 3. There are some grounds for believing the isomerism to be due to keto-enol tautomerism, although no hydroxyl group could be detected by acetylation under various conditions. 4. Geigerin forms a 2:4 dinitrophenylhydazone in the presence of hydrochloric acid, but attempts to prepare derivatives of the ketonic function in the absence of an acid failed. 5. Potassium permanganate is not decolorised by the substance in the cold neither can any acetone be recovered after the action of chromic acid under the proper conditions for the oxidation of isopropyl side-chains to acetone. Such a group is therefore not present in Geigerin. 6. Cold hydrochloric acid of concentration over 10 per cent. affords a very striking colour reaction with Geigerin. The substance dissolves easily, forming a cherry-red solution which shows absorption bands at 543, 506 and 466 mμ. In time, the colour becomes more brown in tint. 7. Geigerin is a monolactone and the corresponding acid, Geigeric acid, has been prepared and found to crystallise in plates. 8. When Geigerin is boiled for l hour with concentrated hydrochloric acid the cerise colour changes to brown and from the reaction mixture an acid was isolated in the form of its methyl ester melting at 98.5°. 9. From results reported in the following communication, it would appear that Geigerin is closely related, chemically, to the active principle of the plant which causes vermeersiekte. Preliminary degradation experiments indicate that on potash fusion a mixture of liquid rancid-smelling acids is produced, and certain reactions suggest that these may belong to the polymethylene series of compounds. 10. On distillation at low temperature with zinc dust, fluorescent, oily aromatic substances are produced. At 700° naphthalene is formed. 11 . When Geigerin is oxillised by hot alkaline potassium permanganate, there arises an acidic fraction from which the methyl ester of an acid, probably in C₁₀H₁₃O₃ (OCH₃), was isolated in crystalline form, M.P. 115-6⁰, and also a neutral, non-volatile substance soluble in ether and slightly soluble in water, which on treatment with dilute mineral acid in the cold at once liberates acetaldehyde. The exact nature of this material awaits further investigation, but attention is drawn to the analogous behaviour of the acetals. 12. It would appear from the literature that Geigerin is in all probability identical with the substance extracted by Thoms from Chrysanthemum cinerariaefolium in 1891 and named by him "Pyrethrosin". His formula for this substance C₃₄H₄₄O₁₀ was put forward with some reserve. 13. Preliminary pharmacological experiments upon rabbits, sheep and cats are reported.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Psilocaulon absimile N.E.Br. as a stock poison. I. Determination of oxalic, malic, tartaric acids, etc

In the course of his investigations into mortality among Angora goats in the Willowmore district of the Cape Province, Steyn strongly suspected a plant, Psilocaulon sp., of being the cause. The plant from the farm was toxic for rabbits, but when grown at Onderstepoort, where the soil conditions are very different, it was non-toxic. The plant contained considerable quantities of oxalic acid, with smaller amounts of malic and tartaric acids, as well as a toxic principle to be described in a later paper and to which the authors attributed the deaths of the goats in the field. The authors discuss the interrelations between the organic acids and their physiological function in plants and conclude with a discussion on the toxicology of oxalic acid and the oxalates.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Studies on the photosensitisation of animals in South Africa. II. The presence of a lethal factor in certain members of the plant genus Tribulus

"Geeldikkop" is a disease of South African sheep, associated with photosensitisation and icterus, caused by Tribulus terrestris and certain other plants. It is shown that a lethal factor is present in the fresh juice and aqueous extracts of Tribulus, which can cause death from asphyxia following intracorpuscular conversions of haemoglobin into methaemoglobin. The responsible agent is an inorganic nitrite, not present as such, but formed from pre-existing nitrate under the influence of an oxido-reductase. This, however, does not account for the naturally occurring " Geeldikkop, " since it does not account for the photosensitivity and icterus. Repeated dosing with sodium nitrite, hydroxylamine hydrochloride, hydrazine sulfate and ammonium carbonate failed to photosensitise sheep. Administration of sodium nitrite, nitrobenzol and amyl nitrite produced death from simple methaemoglobinaemia.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Isolation of the poisonous principle of Dimorphotheca cuneata Less

The toxic substance present in the plant Dimorphoteca cuneata has been isolated and identified as the cyanogenetic glucoside "linamarin" or acetonecyanhydrin glucose ether. An improved method of extraction has been described. The plant contains the enzyme "linamarase" exhibiting a fairly high degree of specificity for its substrate. Quantitative determination shows that Dimorphotheca cuneata in the flowering stage yields about 280 mgm. of HCN per 100 gm. plant, calculated on the dry weight basis. The toxic effects following ingestion of lethal quantities of the plant appear to develop more slowly than is usually the case with Dimorphotheca species.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn2015mn201

Studies on the photosensitisation of animals in South Africa. VII. The nature of the photosensitising agent in geeldikkop

The pigment responsible for the photosensitivity in geeldikkop and also that developing after operative ligature of the bile duct in sheep (experimental icterus) has been isolated and identified as phylloerythrin, a porphyrin derived form chlorophyll. In the absence of chlorophyll from the diet, experimental animals neither became photosensitive nor could phylloerythrin be isolated from the bile, serum or faeces. The agencies responsible for the biological transformation of chlorophyll into phylloerythrin in the sheep are under investigation. Preliminary results show that the phylloerythrin is formed in the fore-stomachs and is probably a product of protozoal or bacterial activity. The icterogenic factor in geeldikkop is still under investigation.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn2015mn201