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Recent works on Stoic logic report that among complete λεκτά only a sub-class was regarded as capable of being true or false: by contrast with statements (ἀξιώματα), such other sentences as questions, orders and oaths do not bear a truth-value. But the situation is a good deal more complicated than that, at least in the case of oaths, which I propose to examine.In characterising all such utterances as ‘sentences’ I do not wish to beg questions which will be discussed below. Surface grammar, with its distinctions of indicative, imperative, interrogative and optative, can mislead us as to the real force of an utterance. In the case of oaths there seems to be no preferred form of expression; and it is a matter for deeper philosophical probing to determine their true relation to other speech-acts.

The fundamental principles of radio-frequency heating are discussed. Microwave frequencies have been selected for a special study because of the availability of efficient magnetron valves for industrial use. The applications of this source of heat for the continuous fixation of dyes on textile fibres have been investigated.

The precise age of the Millstone Grit of South Wales has been in doubt for some years. Although it has been shown to be of Upper Carboniferous age, it has been uncertain whether the whole of the earliest part of the Upper Carboniferous is represented by deposits in southern Britain. Some part of the Millstone Grit of Pembrokeshire has been regarded, on the basis of its flora, as of Middle Coal Measure or Yorkian age (Goode, 1913, p. 272). Similar conclusions have been reached by Dr. R. Crookall concerning part of the Millstone Grit of Somerset (1925, p. 403). As yet, the flora characteristic of the Lanarkian of northern Britain has not been proved to be present in South Wales and elsewhere in south Britain. On the other hand, it has been argued that the absence of a Lanarkian flora does not necessarily imply an important break in the sequence, since recent work on the lamellibranch fauna of various British coalfields points to the conclusion that the lowest part of the Lower Coal Series of South Wales is of approximately the same age as the Lower Coal Measures of northern England (Davies and Trueman, 1927, p. 253).

Pregnancy specific beta glycoprotein is produced by the syncytiotrophoblast and secreted into the maternal peripheral circulation reaching levels of approximately 200 m/liter in normal pregnancy at term. In the present study the distribution of this newly defined placental protein was examined in maternal and fetal compartments in 12 patients at delivery.

The colonization factor antigen I (CFA/I) gene has been isolated and sequenced. The amino acid sequence of CFA/I deduced from the nucleotide sequence is composed of 170 amino acids. The first 23 amino acids are considered to be the signal peptide of the CFA/I protein since they are not present in the protein sequence. Among the remaining amino acids, only two are different from the protein sequence: amino acid position 76 is an aspartic acid instead of an asparagine, and position 97 is a serine instead of an alanine. The CFA/I gene has a typical Shine-Dalgarno sequence located 10 base pairs (bp) upstream from the initiation codon. The sequence TACAAT located 48 bp upstream from the initiation codon was tentatively designated the -10 sequence of the CFA/I gene promoter. No sequences homologous to the consensus -35 promoter sequence was found. A pair of inverted repeat sequences followed by a stretch of eight A's are located 45 bp downstream from the termination codon of the CFA/I gene; this region may be a rho-independent transcriptional terminator.

Technology areas related to gas turbine propulsion systems with potential for application to the automotive gas turbine engine are discussed. Areas included are: system steady-state and transient performance prediction techniques, compressor and turbine design and performance prediction programs and effects of geometry, combustor technology and advanced concepts, and ceramic coatings and materials technology.

Butenyl and pentenyl methyl chalcogenides react, as exemplified for (I), to give complexes (III) and (IV).

Campylobacter pylori infection has been associated with duodenal ulcer, gastric ulcer, and non-ulcer dyspepsia. Although in vitro studies have shown that C. pylori is susceptible to most commonly used antibiotics, predictions from in vitro sensitivity studies have not led to a safe and generally effective therapy; C. pylori has proved to be very difficult to eradicate in vivo. We used the urea breath test to assess the susceptibility of C. pylori in vivo to various drugs. C. pylori was susceptible to bismuth subsalicylate, bismuth subnitrate, and furazolidone. C. pylori was not susceptible (i.e., urease activity remained despite administration of the drug) to the following drugs: 1) antiulcer agents (cimetidine, ranitidine, famotidine, omeprazole, misoprostol, sucralfate, liquid antacids); 2) NSAIDs (aspirin, indomethacin, ibuprofen, naproxen, tolmetin); 3) antibiotics (oral penicillin V, trimethoprim-sulfamethoxazole, dicloxacillin); 4) salts (lithium, ferrous sulfate, gold); 5) miscellaneous (acetaminophen, phenytoin, hydrochlorothiazide, propranolol, metoprolol, metoclopramide, ursodeoxycholic acid). Oral antimicrobials can be administered directly onto the site of infection, so that a very low oral dose will provide many multiples of the in vitro minimal inhibitory concentration. Furazolidone suspension (7 mg) was administered seven times daily (daily dose 49 mg) to three individuals infected by C. pylori during suppression of gastric acid secretion with famotidine (40 mg bid). After 4 days, all subjects had significant reductions in urease activity (two to normal and one to a borderline value). This response suggested that very low-dose therapy may be useful either alone or combined with bismuth. Conclusive establishment of an etiologic (or major contributory) relationship of C. pylori to ulcer disease will require a safe and reliable method to eradicate the organism from the stomach and duodenum.

Campylobacter pylori causes type B gastritis and C. pylori infection has been associated with duodenal ulcer, gastric ulcer, non-ulcer dyspepsia, and gastric cancer. Although we have been able to culture C. pylori for only about 5 years, what we now know about this organism can explain many mysteries surrounding peptic ulcer disease. Whenever one investigates a population of ulcer patients for the presence of any accepted potentially important pathogenetic factors, one finds that the population of patients with duodenal ulcer disease differs (statistically) from those without duodenal ulcer disease, but that to a large degree they also overlap. None of the traditional factors can be considered essential and characteristic of chronic duodenal ulcer. The exception is the presence of a C. pylori infection, the presence of which is almost invariable. Several properties of C. pylori have been identified that might be virulence factors, including (a) provoking a marked acute and chronic inflammatory response, (b) rapid motility through gastric mucus, (c) urease activity, (d) a fibrillar adhesin(s), (e) several putative exotoxins, and (f) microinvasion. We can now add to the old dictum "no acid-no ulcer," "no C. pylori-no ulcer" at least as far as chronic duodenal ulcer disease in adults is concerned.

Molecular orbital calculations on carbido-transition-metal carbonyl cluster compounds where the carbon atom lies in a large cavity indicate a substantial buildup of negative charge on the carbon atom. Besides making the carbon more susceptible to protonic attack the large cavity assists the stabilization of interstitial C-H fragments.

Sheep erythrocytes sensitized by incubation with the heat-labile enterotoxin (LT) of Escherichia coli are hemolyzed in the presence of anti-LT antiserum and complement. The Microtiter (Cooke Laboratory Products) technique was used to titrate anti-LT antibody in serum by this immune hemolysis reaction. Immune hemolysis was inhibited by preexposure of the anti-LT antiserum to soluble LT before addition of the LT-sensitized sheep cells. E. coli mini-extract preparations were obtained by the polymyxin release technique and assayed for LT by the lysis inhibition test (LIT) and by the adrenal cell assay. All 75 adrenal cell-positive E. coli isolates were positive in the LIT assay. Eight of 318 adrenal cell-negative isolates tested were positive in the LIT assay, possibly indicating the presence of biologically inactive toxin.

Immunoprotection against diarrhea caused by colonization factor antigen/I (CFA/I)-positive, human-associated, enterotoxigenic Escherichia coli was investigated using the adult rabbit intestinal temporary ligation technique. An oral dose of 1 X 10(8) viable cells of enterotoxigenic Escherichia coli strain H-10407 (078:H11:CFA/I) produced diarrhea in all animals challenged. Rabbits allowed to survive this challenge dose were re-challenged approximately six weeks later with the result that four of seven (57%) did not develop diarrhea. Peroral immunization of rabbits with purified CFA/I elicited protection against challenge with strain H-10407; this protection was dose-related and CFA/I-specific. Immunoprotection did not correlate with a systemic antibody response. CFA/I produced a relatively poor immune response in terms of the number of IgM- and IgG-producing cells in the lamina propria of the animals but did elicit a vigorous increase in the number of intestinal IgA- and anti-CFA/I-producing cells. There was a highly significant inverse relationship between the number of IgA- and anti-CFA/I-producing cells in the lamina propria of the rabbits and the diarrhea response to the challenge strain H-10407 (correlation coefficients of -0.616 and -0.678 respectively). It is concluded that anti-CFA/I antibody, probably of the IgA class, is the major immune response to orally administered CFA/I and that this response is highly immunoprotective.

The efficacy of a daily dosage regimen of subsalicylate bismuth in preventing or reducing the severity of diarrhea among young healthy adults was evaluated in a double-blind, randomized, placebo-controlled trial. Diarrhea developed in 14 (23%) of 62 students receiving subsalicylate bismuth compared with 40 (61%) of 66 students taking a placebo. The protective effect of subsalicylate bismuth was apparent within a day or two of the study onset and became more obvious as the number of days at risk increased. The students treated with subsalicylate bismuth experienced fewer intestinal complaints and were less likely to pass soft or watery stools of any number. Once diarrhea occurred, enteropathogens were less commonly identified in stools of students receiving subsalicylate bismuth (33%) compared with placebo (71%). Subsalicylate bismuth was well tolerated by students during the 21-day trial.

Colonization factor antigen II-producing enterotoxigenic Escherichia coli serotypes possessed at least one large plasmid. Loss of colonization factor antigen II correlated with either complete or partial loss of the large plasmid. Complete loss of the plasmid always correlated with complete loss of enterotoxin production. Three of five deletion events also correlated with the loss of toxin production.

Colonization factor antigens (CFAs) were administered orally to volunteers, and the mucosal immune response was assessed by measuring secretory immunoglobulin A (IgA) in saliva and intestinal secretions and by challenge with virulent enterotoxigenic Escherichia coli (ETEC). A combination of CFA/I and CFA/II (8 mg each) administered orally in four doses in milk failed to induce a mucosal IgA response and also failed to protect against challenge with CFA-positive ETEC. When CFA was administered orally (1.5 mg divided into three doses with bicarbonate) to volunteers without preexisting serum anti-CFA levels, it failed to elicit a serum IgG or intestinal secretory IgA response or to protect against challenge with virulent ETEC. The CFA is destroyed by acid gastric contents but it induced significant antibody titer rises in 8 of 11 (73%) volunteers with preexisting serum anti-CFA IgG levels after oral administration of 1 mg of CFA/I with sodium bicarbonate. Subcutaneous priming (50 micrograms CFA/I) did not induce a serum IgG response but, when followed by oral boosting (1 mg CFA/I in two divided doses with sodium bicarbonate), induced intestinal anti-CFA secretory IgA in 4 of 8 volunteers and protected against challenge with CFA/I-positive ETEC. These results, although preliminary, are encouraging and demonstrate that it may be possible to develop an effective oral vaccine based on soluble nonreplicating antigens such as purified CFAs.

A 6.1 m long suction trap, with multiple air inlets located on its upwind, top, ends and downwind sides, was placed on a freely pivoting raft moored in a large borrow pit. Air inlets on the downwind side made larger captures than those on the upwind side. Inlets near the top edge of the trap captured larger numbers than those at the bottom. Larger proportions of Culex nigripalpus and Cx. erraticus accumulated behind the horizontal and vertical edges of the trap than did other species. Mosquitoes near the ends of the trap could choose whether to fly over or around the trap; most Cx. nigripalpus and Cx. erraticus flew over the trap while only Cx. pilosus favored going around the ends. Other species appeared to fly over and around the trap in approximately equal numbers. No evidence was found that flight patterns changed with differing wind velocities.

Recommendations for the prevention of tetanus in the wounded have been revised to incorporate the use of human tetanus immunoglobulin, which is now available in the United Kingdom. Surgical toilet is of prime importance for all wounds, and is usually sufficient for tetanus prophylaxis in patients with wounds that are less than six hours old, clean, non-penetrating, and with negligible tissue damage. Human tetanus immunoglobulin should be given to patients with more serious wounds sho have had toxoid injections over 10 years earlier, had an incomplete course, or do not know their immunity status. The importance of active immunization is emphasized. The recommendations should be regarded as guidelines as the circumstances in individual cases will differ.