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Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Background An algorithm that identifies individuals with a digital electronic health record (EHR) signature homologous to patients with atrial fibrillation (AF) could delineate a subpopulation that may benefit from early interventions to reduce future adverse events. Purpose We aimed to train and test a scalable algorithm to identify individuals at higher risk of incident AF in the short-term, and quantify associations with AF and a range of other conditions. Methods We used UK primary care EHR data from individuals aged ≥30 years without known AF in the CPRD-GOLD dataset (Jan 2, 1998, Nov 30, 2018), randomly divided into training (80%) and testing (20%) datasets. We trained a random forest classifier using age, sex, ethnicity and comorbidities (FIND-AF). Performance was evaluated in the testing dataset with internal bootstrap validation with 200 samples, and compared against the CHA2DS2-VASc and C2HEST scores. We calculated the cumulative incidence rate for AF, heart failure, valvular heart disease (and specifically aortic stenosis), MI, stroke or TIA, peripheral vascular disease, CKD, diabetes and COPD. Incident diagnoses were the first record of that condition in primary or secondary care records from any diagnostic position. We excluded individuals for the analysis of each condition who had a preceding diagnosis of that condition. Fine and Gray’s models with competing risk of death were fit for each condition between higher and lower predicted AF risk. Results FIND-AF could be applied to 100% of records for 2 081 139 individuals in the cohort. In the testing dataset (n = 416 228), individuals at higher predicted AF risk had similar baseline characteristics to individuals who developed incident AF (Table 1). Prediction performance for AF was strongest for FIND-AF (AUROC 0·824, 95% CI 0·813-0·829; Brier score 0.069) compared with CHA2DS2-VASc (0·784, 0·773-0·794; 0.093) and C2HEST (0·757, 0·744-0·770; 0.102). FIND-AF demonstrated favourable reclassification and superior net benefit on decision curve analysis, with robust performance in both sexes and across ethnic groups. The higher predicted risk cohort, compared to lower predicted risk, had a 20-fold higher 6-month incidence rate for AF and higher long-term risk of AF (HR 8·75, 95% CI 8·44-9·06), but also incident heart failure (HR 12.54, 95% CI 12.08-13.01) aortic stenosis (9.98, 9.16-10.87), stroke/TIA (8.07, 7.80-8.34), CKD (6.85, 6.70-7.00), peripheral vascular disease (6.62, 6.28-6.98), valvular heart disease (6.49, 6.14-6.85), MI (5.02, 4.82-5.22), diabetes (2.05, 2.00-2.10) and COPD (2.02, 2.00-2.05) (Figure 1). This cohort were also at higher risk of death (10.45, 10.23-10.68), accounting for 71% of cardiovascular deaths. Conclusions FIND-AF is applicable to national electronic health records data, identifies people at higher risk of incident AF within the next 6 months with good performance, and predicts risk of a range of other conditions and death.

All aspects of health care are under intense scrutiny, none more so than the competence of health care professionals to diagnose and manage disease. Correctly, patients expect those who minister to them to be competent and properly trained. Concepts of what constitutes a good and a bad doctor vary widely. Good may equate with sympathy, yet sympathy is no substitute for ability. The question of competence has received relatively scant attention but is now an important issue. Establishing competence requires setting standards and usually setting conditions for maintaining clinical acumen and ability. Such is laudable, particularly as it can bring about constructive retraining and can divert specific clinical problems to those best able to deal with them. Specific circumscribed procedures have been an obvious first target for criteria of competence. Such procedures are amenable to audit and are performed in sufficient numbers to establish average rates for success, failure, and efficiency. Standards of competence have been suggested for areas such as angioplasty and stenting.1 Cardiac electrophysiological procedures have also been examined and are similarly amenable to suggestions for levels of competence.2 3 Competence involves exposure to and performance of procedures but more importantly it should include an audit of complications and success. It is to be expected that those with the greatest exposure are likely to be those most competent although this relation is not necessarily so simple. Experience in dealing with complications or anticipating their occurrence plays a large part in the successful performance of many clinical procedures, cardiac electrophysiological ones included. Establishing and maintaining levels of competence in those performing procedures is very desirable. It identifies those who can be expected to offer safe modern care, and it helps to identify manpower needs for given disease situations. There are, however, problems with establishing strict guidelines for …

OBJECTIVE--To assess the possible benefits of intravenous isosorbide dinitrate in acute myocardial infarction and oral isosorbide mononitrate in subacute myocardial infarction. METHODS--316 patients presenting with acute myocardial infarction were entered into double blind placebo controlled clinical trials assessing infarct size by enzyme release, ventricular size and function by echocardiography, reperfusion by continuous 12 lead ST segment monitoring and late potentials by high resolution electrocardiography. RESULTS--301 patients, of whom 292 (97%) received thrombolytic treatment, were randomised on admission to intravenous isosorbide dinitrate or placebo. Overall, there was no significant effect of treatment on infarct size, ST segment resolution, ventricular remodelling, or late potentials at day 3. A trend was observed towards a reduction in infarct size in patients with non-Q wave infarction treated with isosorbide dinitrate. Heterogeneity of nitrate effect was observed in relation to the degree of ST segment elevation on presentation with a clear benefit of isosorbide dinitrate in patients with moderate ST segment elevation (472 U/l v 704 U/l, P = 0.003) and a trend towards a deleterious effect in patients with marked ST segment elevation (1152 U/l v 1058 U/l, P = 0.2). ST segment re-elevation was more common among patients receiving nitrate treatment than in those assigned to placebo (29 v 16, P < 0.05). Some 160 patients underwent a further randomisation to sustained release isosorbide mononitrate or placebo on day 3. Echocardiographic volumes after 6 weeks of treatment were similar in the two groups. CONCLUSIONS--No benefit was observed with administration of nitrates in the treatment groups as a whole for either acute or subacute infarction. There was, however, evidence of heterogeneity of effect in the different subgroups of acute infarction, and the possibility that nitrates may have differing actions in different groups of patients should be considered.

BACKGROUND Arrhythmias are common in patients who have developed ventricular enlargement after myocardial infarction. METHODS AND RESULTS A prospective study was undertaken to assess the relation between ventricular dilatation and the development of late potentials after myocardial infarction. Echocardiograms and signal-averaged ECGs were recorded on days 1,3,7, and 42 in 52 patients with a first anterior myocardial infarction. Twenty-nine percent of patients were late potential-positive on their initial signal-averaged ECG recorded on the day of admission. The incidence of late potentials rose during the next week to a peak of 42% at day 7, declining to 13% by day 42. The presence of late potentials on the day of admission was associated with an increase in end-diastolic volume index of 16.1 +/- 6.0 mL/m2 (mean +/- SEM), compared with a decreased of 4.7 +/- 2.7 mL/m2 among late potential-negative patients (P < .006). Qualitatively similar results were evident for late potentials on day 3 and day 7. By contrast, there was no association between late potentials on day 42 and ventricular dilatation. Marked dynamic changes in late potentials were evident during the first week. Patients with persistent late potentials (n = 9) on all three recordings in the first week showed a marked increase in end-diastolic volume index of 21.3 +/- 8.1 mL/m2 (P < .005 in comparison with patients who were persistently negative [n = 20]). Patients demonstrating dynamic positivity (n = 15) not present on all three recordings in the first week showed no significant increase in end-diastolic volume index. CONCLUSION It is concluded that late potentials during the first week after infarction are associated with subsequent ventricular dilatation. These early-phase late potentials may be a manifestation of cell slippage. They arise before gross topographical enlargement and may serve as a predictor of ventricular dilatation.

Study objective – Contraction-excitation feedback may play a role in arrhythmogenesis in heart failure. The aims of this study were to determine whether contraction-excitation feedback has a significant effect on action potential duration within a physiological range of pressures, and to investigate the individual effects of left ventricular end diastolic and peak systolic pressures on action potential duration. Design – A new model was developed for studying contraction-excitation feedback in a physiologically electing isolated heart preparation. Hearts were perfused via the left atrium, electing against an aortic afterload. By varying left atrial and aortic pressures, left ventricular end diastolic pressure and left ventricular peak systolic pressure were controlled independently. Intracellular potentials were recorded from the epicardium. Experimental material – Hearts (n = 33) were obtained from guinea pigs weighing 300-350 g. Measurements and main results – Increasing left ventricular end diastolic pressure from 0.3 to 1.1 kPa (2.2 to 8.3 mm Hg), at constant left ventricular peak systolic pressure, shortened action potential duration by 11.3(SEM 1.5) ms (p

The evidence base for implantable cardioverter-defibrillator (ICD) therapy requires expansion of guidance/indications to allow UK physicians to treat a broader range of patients. The ICD clinical consultees to the National Institute for Health and Clinical Excellence (NICE) review current guidance/guidelines, explain the evidence base, and suggest a UK ICD implantation strategy.

A 14-year-old girl with right ventricular dysplasia and recurrent drug refractory ventricular tachycardia underwent thoracoscopic mapping cryoablation. Good access to the right ventricular free wall was obtained. We suggest this technique may have an important role in the management of patients with right ventricular tachycardia.

OBJECTIVE—To explore the current use of secondary preventive treatment in survivors of out of hospital cardiac arrest without myocardial infarction (primary ventricular tachycardia/ventricular fibrillation (VT/VF)) in West Yorkshire, and assess the implications of recent studies on the benefits of implantable cardioverter-defibrillators (AICD) in this context. DESIGN—Retrospective analysis of an ambulance service based database of outcome after resuscitation of out of hospital cardiac arrest and the Leeds AICD implantation database. MAIN OUTCOME MEASURES—Mortality, rate of referral for specialist investigation, antiarrhythmic treatment. RESULTS—Twelve month mortality following successful discharge after primary VF arrest was 15%. Of 53 patients with primary VF/VT, 29 apparently did not see a cardiologist during the initial admission. Amiodarone was the most widely used antiarrhythmic agent. Six patients (15%) received an AICD. During the same period 22 patients from the same catchment area received an AICD following an in-hospital cardiac arrest. CONCLUSIONS—Mortality among survivors of non-infarct related prehospital cardiac arrest remains significant, with few patients being referred for specialist investigation. The implementation of recent guidelines on AICD use in cardiac arrest survivors would have resulted in an approximate 60% increase in the total numbers of defibrillators implanted in the West Yorkshire area. Keywords: ventricular fibrillation; ventricular tachycardia; primary arrhythmias; implantable cardioverter-defibrillator

In addition to well-established roles in the management of stable angina, unstable angina and heart failure, nitrates are widely used in the management of acute infarction and the subacute period of recovery after infarction. A meta-analysis suggested that intravenous nitrate therapy in acute infarction reduced mortality by 35%. Subsequently, two recently reported 'mega' trials, GISSI-3 and ISIS-4, addressed the role of nitrates during and after infarction. The results of the mega trials have failed to substantiate a statistically significant benefit for nitrates. The contrast between the promising results of the meta-analysis and the disappointing results of the mega trials raises a number of issues considered in this paper. The role of nitrates in acute myocardial infarction remains unclear. The mega trials do offer some suggestive evidence of an early benefit of nitrate therapy. If any benefit does exist, it must be much smaller than the 35% reduction in mortality suggested by the meta-analysis. Further trials are required to assess the possibility of an early acute benefit. Any benefits will probably apply only to subgroups of infarcts.

Measurement of action potential duration is made more valuable if it can be made simultaneously with other variables, to which it may be related. We have developed a microcomputer-based system which allows measurement of action potential duration, both for transmembrane action potentials and for monophasic action potentials. The system allows simultaneous recording and analysis of action potentials and intraventricular pressures. Both end-diastolic and maximum systolic pressures have been analysed. Action potential duration was assessed at four different levels of the repolarization curve. We have analysed the consistency of measurements made by the computer, and compared them to measurements made manually, using results from six dog experiments. For action potential duration, there was no systematic difference between the manual and the computer methods, but the computer was significantly more consistent. In the case of the pressure measurements, the two methods were approximately the same in their consistency, and again there was no systematic difference. We have demonstrated that potential errors in determination of the average diastolic potential did not significantly affect the results obtained by our method. The variances of action potential duration measurements made at different levels of repolarization were equal. We demonstrated that there was no effect of amplitude on the action potential duration of potentials recorded under steady-state conditions.

1. Although it is known that mechanical events in the heart influence the duration of the cardiac action potential, there is no quantitative information on the effects of independent changes in ventricular end-diastolic and systolic pressures. 2. Experiments were carried out on open-chest anaesthetized dogs in which the autonomic nervous influences on the heart were prevented and monophasic action potentials were recorded form the epicardial surface of the left ventricle. The duration of these action potentials was taken as the interval from the upstroke to the point of 90% repolarization. 3. Elevation of left ventricular peak systolic pressure, at constant end-diastolic pressure, significantly shortened the monophasic action potential. 4. Elevation of end-diastolic pressure at constant peak systolic pressure significantly lengthened the monophasic action potential. 5. Responses were not dependent on release of noradrenaline from sympathetic nerve terminals because they persisted after administration of bretylium tosylate. They were also not due to myocardial ischaemia because they persisted when coronary perfusion pressure was maintained at a constant high level. 6. Simultaneous recordings of changes in myocardial segment length showed the expected responses to changes in ventricular pressures: increases in shortening in response to increases in diastolic pressure and no consistent effect from changes in systolic pressure. 7. These investigations demonstrate the independent effects of changes in systolic and end-diastolic pressures on cardiac action potential duration. This effect is likely to be an effect of the mechanical events, i.e. contraction-excitation feedback. This response may be mediated through changes in myocardial fibre tension, the consequent changes in fibre shortening, or both.

Objectives —To study the differences between endocardial bipolar and unipolar ventricular paced evoked responses and surface electrocardiograms. Patients —10 patients with conduction system disease awaiting insertion of a permanent pacemaker were studied with temporary ventricular pacing from the right ventricular apex. Main outcome measure —Comparison of the durations of the QRS complexes and QTa and QTe intervals of the endocardial bipolar paced evoked response and the surface electrocardiogram with those of the reference unipolar paced evoked response. Results —By comparison with the unipolar reference, the mean durations of the QRS complexes of the bipolar signal and the surface electrocardiogram were 41·8% and 132·1% respectively. The mean QTa interval was 85·9% and 112·2% respectively and the mean QTe interval was 86·9% and 109·5% respectively. All these differences were significant. The amplitudes of the unipolar QRS complexes and T waves were significantly larger than those recorded in the bipolar configuration. Conclusions —Differences between the unipolar and bipolar ventricular paced evoked responses are significant. The time course of the unipolar signal is closer to that of the surface electrocardiogram. This indicates that the unipolar paced evoked response does not reflect local electrophysiological events, as has been suggested previously.

Emergency cardiac surgery after recent thrombolytic therapy is associated with increased blood loss. A patient underwent emergency repair of a ruptured left ventricle after intravenous streptokinase treatment for acute coronary occlusion. High dose aprotinin was given during the operation to reduce the expected blood loss. Surgical repair was successful without bleeding complications. Total postoperative blood loss was 365 ml.

Arrhythmias remain a major cause of late mortality following myocardial infarction. They arise due to fibrosis within the infarct, which creates the conditions of slow conduction necessary for re-entry. In individual patients who have already manifested a malignant arrhythmia, antiarrhythmic drug therapy, guided by invasive electrophysiological testing, is of proven benefit in prolonging survival. By contrast, when used on a population basis, antiarrhythmic drug therapy has proved singularly ineffective. This is illustrated by the recent Cardiac Arrhythmia Suppression Trial (CAST) study--far from improving survival, antiarrhythmic therapy increased mortality. The use of antiarrhythmic drugs on a population basis is therefore fundamentally flawed. Hemodynamic intervention provides an alternative strategy in arrhythmia prevention. Hemodynamic changes may influence electrophysiological parameters and arrhythmogenesis in a number of ways. First, myocardial stretch may contribute to arrhythmogenesis through contraction-excitation feedback. Second, hemodynamic changes can influence ventricular remodeling following infarction, which may be an important determinant of subsequent arrhythmogenesis. Hemodynamic intervention, therefore, represents a promising new approach to arrhythmia prevention following myocardial infarction.

Epicardial activation and repolarisation sequences were investigated in patients with upright or inverted T waves in left ventricular leads of the surface electrocardiogram. Fifteen patients were studied: 10 were undergoing coronary artery bypass grafting (upright T waves) and five aortic valve replacement (four patients with T inversion). Monophasic action potentials were recorded intraoperatively from eight to 10 left ventricular sites in each patient. In patients with upright T waves there was an inverse relation between the duration of the monophasic action potential and the activation time (mean slope -1.44). As a consequence, activation and repolarisation proceeded in opposite directions. Dispersion of repolarisation time (14 ms) was less than dispersion of activation time (23 ms). In patients with T wave inversion caused by aortic stenosis there was no relation between the duration of action potential and activation time; the repolarisation sequence resembled the activation sequence, and the dispersion of repolarisation time was greater than the dispersion of activation time (31 and 26 ms respectively). These results show that there are epicardial repolarisation gradients in man and that these are related to the configuration of the T wave. In patients with upright T waves an inverse relation between the duration of the action potential and the activation time reduces the dispersion of the repolarisation time. When the T wave was inverted this relation was no longer found and the dispersion of repolarisation increased.

A technique for recording somatosensory evoked potentials after stimulation of the patellar branch of the saphenous nerve is described and the results from 11 normal subjects and from two patients with intraabdominal femoral nerve injuries are presented. One patients developed a nerve lesion after an abdominal surgical procedure and the second suffered a gunshot wound causing femoral nerve paralysis. Both patients recovered spontaneously. Evoked potentials from saphenous nerves showed a significant discrepancy between faster motor recovery and delay in reinstating sensory axonal conduction.

Nitrates are widely used in anginal prophylaxis. In spite of the fact that the concept of nitrate tolerance was first put forward many years ago, the question of tolerance has remained controversial. There is widespread agreement that tolerance does occur to the effects of nitrates on arterial pressure. In contrast, tolerance to the venous and pulmonary effects is disputed. Similarly, the possibility of tolerance to the antianginal effects remains at issue. In this review, I discuss the factors which may have contributed to conflicting results in different studies, in particular recent findings on the rapidity of onset and reversal of tolerance. Tolerance develops rapidly on initiation of treatment and disappears equally rapidly on its discontinuation. In addition, tolerance appears to be a function of plasma nitrate profile. It is most likely to occur when plasma nitrate levels are constant and least likely when nitrate levels fluctuate. Furthermore, the provision of a daily nitrate free interval may protect against the development of tolerance. I then discuss the implications of these findings for patient management. They suggest that nitrate prophylaxis should not be used continuously, if this can be avoided. Rather, prophylaxis should be tailored to the individual to provide protection at times of maximum susceptibility, while allowing nitrate levels to fall at other times. The adequacy of antianginal protection with drug regimens incorporating a nitrate free interval requires further assessment. Similarly, the possibility that a nitrate free interval might lead to withdrawal effects and exacerbation of angina needs to be excluded.

A simple method was developed for recording epicardial monophasic action potentials intraoperatively in man. Potentials were recorded rapidly and reliably from multiple epicardial sites using a hand-held probe. The feasibility of repolarization mapping was assessed in 30 patients. It was possible to record technically adequate signals from most left ventricular and posterior right ventricular sites (success rates 72% and 61%, respectively), but it was more difficult to achieve satisfactory recordings over the free wall of the right ventricle (success rate 36%). The onset of cardiopulmonary bypass resulted in a transient rise in action potential duration of approximately 30-40 ms in the first minutes of bypass. An approximate steady state was achieved thereafter. Reproducibility of the method was assessed by mapping a small number of sites repeatedly. The 95% confidence limits for an estimate of repolarization time, based on a single potential, were +/- 21 ms. With 4 probe applications at each site, the confidence limits of the estimated site mean were reduced to +/- 8 ms. Based on this approach, statistically significant differences between sites were demonstrated in 9 of 10 patients, confirming that the method is sensitive enough to provide information on regional differences in repolarization. Intraoperative epicardial repolarization mapping has been shown to be a practical possibility. The technique holds promise as a means of assessing the role of dispersion of repolarization in arrhythmogenesis in man.

Thirty-four patients with atrial fibrillation complicating suspected acute myocardial infarction were randomised to treatment with intravenous amiodarone (n = 18) or intravenous digoxin (n = 16). After 24 h, similar proportions of patients in each group had reverted to sinus rhythm. However, there was a tendency towards earlier reversion with amiodarone. At 4 h, 72% of the amiodarone group had reverted to sinus rhythm, compared with 31% of the digoxin group (p less than 0.1). This tendency was more marked in patients with definite infarction (at 4 h, amiodarone 75% reversion, digoxin 10% reversion). Neither drug had a significant effect on blood pressure. Atrial fibrillation may cause serious haemodynamic deterioration in acute myocardial infarction. In comparison with digoxin, amiodarone offers more rapid control of the ventricular response rate and may, in addition, restore sinus rhythm more rapidly.

Molecular distillation of deodorizer condensates followed by chromatography on alumina, gave substantial quantities of hydrocarbons free of other unsaponifiable constituents. Squalene comprised 50% of the hydrocarbon fraction and contained practically all the unsaturation. A crystalline, saturated hydrocarbon fraction of 4.2% was composed primarily of C29 and C31 paraffins. An unresolved fraction was composed of two major components, each estimated to contain about 30 or 35 carbon atoms. Minor amounts of many hydrocarbons with chain lengths of 15\s-35 carbon atoms were present but not completely identified. C14 analysis showed that the hydrocarbons are natural to soybean oil and they are not artifacts arising from petroleum solvent residues.

Adducts of methyl linoleate with itaconic and citraconic anhydrides have been prepared. Each adduct was separated into monomeric and polymeric components. With ethylene diamine, the itaconic and citraconic polymeric adducts gave gelled products at 170° in one hour and 3.5 hours, respectively. The adduct of citraconic anhydride and monomeric distillate gave a tough, tacky resin which did not gel during a reaction time of 20 hours at 170°–180°.

Adducts of maleic anhydride with methyl oleate, methyl linoleate, and monomeric distillate have been prepared. Reaction of the adducts with ethylene diamine gave a linear, soluble polyamide in the case of the oleate adduct, but gelation occurred at a low degree of reaction with other adducts. The linoleate adduct was separated into monomeric and polymeric components. It is suggested that this polymeric component is responsible for the rapid gelation of polyamides from the adducts of methyl linoleate and monomeric distillate.

Inter-esterification and isomerization reactions offer opportunities to modify drying oils by changing the arrangement of the acids in the fats and oils and by changing the arrangement of double bonds and the groups around the double bonds in the fat acid chains. Although much work has been completed, much more remains to be done.

Research conducted at the Northern Laboratory on vegetable oils during the past two decades includes polymerization, isomerization, flavor stability, and structure. Some early accomplishments—dimeric fatty acids and their derivatives, conjugated oils and their aftertack as well as the use of citric acid to inactivate iron in soybean oil—and more recent accomplishments—aldehyde oils, cyclic fatty acids, and tests for hidden oxidation and hydrazine reduction—are among the subjects reviewed.

The shell drain condensate from a commercial soybean oil deodorizer was analyzed for nonpolar unsaponifiable constituents by liquid-liquid partition chromatography. A procedure for obtaining large quantities of these nonpolar constituents for flavor studies is described, and data on extraction techniques, purification, and analyses are presented. High-purity soy sterols can be obtained as a by-product.

Certain ester-acetal derivatives of azelaaldehydic acid have been evaluated as a new type of plasticizer of PVC. In gerneral, these compouonds have high compatibility and impart excellent low-temperature, mechanical, heat- and light -stability properties to the plasticized PVC. The 2-ethylihexyl ester bis (2-methoxyethyl) acetal, in particular, appeared to have the best combination of properties for a useful plasticizer. The results indicate that a unique and useful type of plasticizer-stabilizer can be obtained from derivatives of azelaaldehydic acid.

The acrylic esters of carnuba wax alcohols and the vinyl esters of nonhydroxy carnuba wax acids have been synthesized. The acrylic and vinyl esters have been homopolymerized and copolymerized with vinyl chloride. Acrylonitrile–acrylic ester copolymers also have been prepared. The copolymers were quite brittle when molding was attempted.

Hydrolytic, reductive and pyrolytic decompositions of ozonolysis products formed in water were surveyed as potential preparative routes to aldehydes. Water is an effective ozonolysis medium and reacts with the transient zwitterion formed during ozonolysis in the same manner as participating solvents. Reductive decomposition proved to be superior to either hydrolytic or pyrolytic decomposition for the preparation of aldehydes. Pyrolytic decomposition, as carried out in the injection port of a gas chromatograph, gave varying amounts and types of products depending upon the type of ozonolysis product used. Interconversion of the various types of ozonolysis products, including ozonides, methoxy hydroperoxides, acetoxy hydroperoxides and hydroxy hydroperoxides, does not occur except under acid catalysis.

Copolymers and terpolymers, based on vinyl ethers from linseed conjugated fatty alcohols and selected as having the most potential for commercial use, were evaluated as chemically resistant coatings, metal-decorating coatings, small-applicance and architectural finishes, wire coatings, and adhesives. Studies show these materials to have promise in areas where a high-temperature baking schedule can be tolerated and where color is not of prime importance. Good compatibility with most commonly used pigments was observed. As wire coatings, film showed good continuity and had superior dielectric strength and resistance to cut-through; however, improvement in flexibility and adhesion to copper would be needed for successful application. Performance as adhesives was disappointing, since curing in the absence of air was poor. The polymers showed some promise as can coatings, but the need for modifications in them was demonstrated.

Sources of edible oils high in polyunsaturated fatty acids are reviewed, as are the availability and composition of these oils and the products derived from them.

Synthetic oils have been prepared from residual dimerized fat acids with soybean and linseed fat acids by esterification with polyalcohols, and with or without maleic anhydride or phthalic anhydride. Preliminary evaluation indicates that these oils give films which dry faster and are more resistant to water and alkali than linseed oil films. This enhancement of water and alkali resistance may result from an increase in C-C bonds present in the films. Ester gum varnishes made from these oils were not markedly superior to similar varnishes made from linseed oil.

The preparation and properties of various polyamides, copolyamides, and modified polyamides, of polymeric fat acids have been described. These polymers are of interest because of their unusual properties and because of the unsaturation and relatively high molecular weight of the polybasic acids involved. Despite the presence of tribasic acids in polymeric fat acids, ungelled polymers having molecular weights of 3,000 to 5,000 are obtainable. A brief discussion has been given concerning the application of theoretical principles of polymerization to the preparation of these polymers. Possible industrial uses for the polyamides are indicated.

3,9-Bis(7-carbomethoxyheptyl)-2,4,8,10-tetraoxaspiro[5.5]-undecane (the pentaerythritol acetal of methyl azelaaldehydate) in the presence of basic catalysts underwent condensation polymerization with ethylene glycol to give linear polymers, either alone or in conjunction with other dibasic esters. These linear poly(ester-acetals) were susceptible to crosslinking by p-toluenesulfonic acid and by various metal oxides and salts, such as zinc oxide, zinc acetate, litharge, and magnesium oxide. The crosslinked polymers were insoluble, infusible, transparent solids which were strongly adherent to glass.

9-Aminononamide, a potential intermediate for nylon-9, was prepared from soybean oil via alkyl soyate, aldehyde oil or soybean amides. All three routes involved various sequences for reductive ozonolysis, reductive amination and ammonolysis. The preferred route is through the alkyl soyates, although the other two have fewer steps. The amino amide is a water-soluble, strongly basic solid that rapidly absorbs atmospheric carbon dioxide and is readily hydrolyzed to 9-aminononanoic acid. Although the amino amide is selfpolymerizable in limited degree, the preferred monomer for nylon-9 is the amino acid. Other new compounds prepared and characterized include azelaaldehydamide, bis(8-carbamoyloctyl)amine; N-(8-carbamoyloctyl)-8-methoxycarbonyloctylamine; 9-hydroxynonanamide; and dimers of the amino amide and the amino ester.