Studies in the dithiole series

Using previously developed methods, several new dithiolium salts have been prepared, and others have been synthesised by modification of Known methods. 3-Benzyl-5-phenyl-I,2-ditniolium perchlorate has been prepared by reaction of benzoylphenylacetone with hydrogen disulphide in ethereal hydrogen chloride, 3-chloro-5-phenyl-i,2-dithiolium perchlorate by chlorination of 5-phenyl-l,2-dithiole-3-thione, and the unsubstituted 1,2-dithiolium cation by peracetic acid oxidation of I,2-dithiole-3-thione. Peracetic acid oxidation of I,3-dithiole-2-thione and its 4-phenyl derivative provided the I,3-ditnioliura system and its 4-phenyl derivative. Cyclisation of S-phenacyl--phenyl (dithioacstate) in ether with boron trifluoride furnished the known 2-benzyl-4-phenyl-l,3-dithiolium cation. The reactions of several dithiolium salts with nucleophilic reagents have been studied. The 1,2-dithiolium cation and its 4-phenyl derivative decomposed by reaction with anionic species to produce l,2-dithiole-3-thiones but the 4-phenyl compound produced 4-phenylisothiazole by reaction with ammonium acetate. Reaction in benzene suspension with ammonia produced bis (4- phenyl-l,2-dithiole-3-yl) sulphide, with aniline it produced cis-phenylmalondialdehydedianil. Related reactions of 5-phenyl and 3,5-diphenyl-l,2-dithiolium per¬ chlorate produced anilinopropenethione derivatives. In cold ethanol methylaniline reacted with 5-phenyl-I,2-dithiolium perchlorate to produce one of the above types of derivatives. In hot ethanol a hydride ion was lost oxidatively to produce 3-(p-methylamino- 5 phenyl^pnenyl-1,2-dithiolium salt. A similar reaction with 4-pheny1-1,2- dithiolium perchlorate failed to give a solid product. 3,5-Dipheny.l-I,2-dithiolium perchlorate reacted with sodium ethoxide to produce 3-ethoxy-3,5-diphenyl-I,2-aithiole. With diethyl-sodiomalonate it furnished 4,b-diphenyl-3-ethoxycarbonyl-thiopyran-2r-one by rearrangement. 2,4,5-Triphenyl-l,3-dithiolium perchlorate reacted with ethoxide and cyanide ions to produce the corresponding 2- substituted tripheny1-1,3- dithiole derivatives. Ammonia gave the 2-amino derivative, but in alcohol or acetic acid this decomposed with-the production of desoxybenzoin,thiobenzamide, triphenyl-I,3-dithiole and triphenyl thiazole

Cancer of the stomach with special reference to early diagnosis in general practice

(1) Cancer of the stomach is at once the commonest and causes the highest mortality of all forms of carcinoma. (2) Failure to make an early diagnosis is the factor chiefly responsible for the continued high mortality. Improvement does not lie in more extensive operations. (3) This failure is due to:- (a) Time lost by the patient, i.e., delay between the onset of vague symptoms and the consulting of a doctor. (b) Time lost by the doctor in the treatment of symptoma without investigating their cause. (4) Patients must therefore be educated against the danger of treating themselves for indigestion or for vague ill-health. This can be done by the family doctor. (5) The doctor must investigate first and treat last. This implies that in every case of dyspepsia or of vague ill -health the possibility of cancer of the stomach must be thought of and steps taken at once to exclude it by the use of clinical methods. (6) Early diagnosis can be made by the joint use of clinical, radiological and if necessary surgical means. (7) The greatest of these are the clinical, because they are the earliest. It follows, therefore, that in the fight against cancer the general practitioner must play a leading part. (8) Investigation by means of gastric analysis is an invaluable aid to the diagnostician and is within the scope of every general practitioner. (9) The routine investigation of all suspicious cases by this method would at least lead to a correct diagnosis being made, or a strong probability being aroused, within two weeks of the patient consulting. (10) Cases would, as a result, be sent oftener and earlier for X -ray investigation, which, in the hands of the expert, is capable of making a correct diagnosis in 96 per cent of cases. (11) Modern surgery has proved that it can cure; the above routine of investigation would afford it the opportunity. Mortality would be reduced and life prolonged

Raeburn, life and art

This thesis gives the biography of the Scottish portrait painter Sir Henry Raeburn R.A. (1756-1823), an outline of his training, a description of his stylistic development and a catalogue of his works.The problem of his activities as a miniaturist is addressed: only two are known but he is reported to have produced many. It is proposed that mourning jewels, made when he was an apprentice goldsmith, may have constituted part of this lost body of work. Raeburn was given some training by David Deuchar (1743-1808), Alexander Runciman (1736- 1785) and David Martin (1737-1798). New evidence relating to Raeburn's time with Martin is given. Raeburn's portrait George Chalmers of Pittencrieff is not accepted as dating from before the trip to Rome. Only one independent portrait commission is dated in the thesis to that period. It is suggested that as an artist Raeburn was a probationer when he left Scotland and that he rapidly matured in Italy. He studied in Rome from 1784 - c. 1787 in the circle of James Byres (1734-1817). An important portrait from his Roman years has been uncovered. He returned to Scotland in about 1787 and spent his entire career in Edinburgh. It is argued that it was his time in Italy which formed his early style, rather than some presumed contact with the work of Reynolds.Raeburn's painting of c. 1800 responded to new concerns. He is also recorded as working as an underwriter shortly after that date. For an unknown reason the artist went bankrupt in 1808. New documents pn this matter are presented.An examination is made of the widely held view that Raeburn's late style was due to a trip he made to London in 1810. Proof is given dating from before 1810 of a move in this new artistic direction.Those with closed minds on Raeburn, holding views formulated ninety years ago, will not read these sections with pleasure.The catalogue contains slightly more than eight hundred entries dealing with almost one thousand works. Dating Raeburn's portraits is difficult and consequently the catalogue is arranged alphabetically. The catalogue contains entries on the copies Raeburn made after the works of other artists and entries on works known only from archival sources. Rejected works are not listed. The thesis does not deal with Raeburn's influence on other painters

How climate change is affecting sea levels

Sea level rise increases the frequency and severity of storm surges and coastal flooding, causing serious damage to critical infrastructure and leading to the displacement of coastal communities around the world. Globally, more than 600 million people live in low‐lying coastal areas at less than 10m elevation, and the population of these regions is expected to exceed 1 billion by 2050 (Neumann et al., 2015). In the United Kingdom, current annual damages from coastal flooding are estimated at over £500 million per year (Edwards, 2017), and costs of damage are likely to increase under projections of future sea level rise

Looking for opportunities : challenges in professional procurement search

Procurement legislation stipulates that information about the goods, services, or works, that tax-funded authorities wish to purchase are made publicly available in a procurement contract notice. However, for businesses wishing to tender for such competitive opportunities, finding relevant procurement contract notices presents a challenging professional search task. In this talk, we will provide an overview of procurement search and then describe the challenges in addressing the related search and recommendation tasks

Racial and Ethnic Diversity in Undergraduate Social Work Programs: How are Programs in Rural Areas Faring?

Social work programs have a long-standing commitment to recruiting and educating racially and ethnically diverse students. However, some programs in rural areas have greater difficulty meeting this commitment. This study examined racial and ethnic diversity within baccalaureate social work (BSW) programs, focusing primarily on student enrollment, faculty, perceptions of diversity, and interventions to attract students. Program directors of BSW programs from 10 Midwestern states were surveyed. Forty-two programs responded. The results indicate that as a whole, social work programs differ in their levels of racial and ethnic diversity. However, BSW programs in rural areas tend to have fewer students and fewer faculty who are racially or ethnically diverse. BSW program directors recognize lack of diversity as an issue, yet strategies that have been used to increase diversity have been only minimally effective. Implications for social work programs and strategies to enhance diversity are discussed

No evidence of dioxin cancer threshold.

The U.S. Environmental Protection Agency (EPA) has developed an estimate of the human cancer risk from dioxin, using the standard low-dose linear extrapolation approach. This estimate has been controversial because of concern that it may overestimate the cancer risk. An alternative approach has been published and was presented to the U.S. EPA Science Advisory Board's Dioxin Review Panel in November 2000. That approach suggests that dioxin is a threshold carcinogen and that the threshold is an order of magnitude above the exposure levels of the general population. We have reexamined the threshold analysis and found that the data have been incorrectly weighted by cohort size. In our reanalysis, without the incorrect weighting, the threshold effect disappears