First Observation of Cyclotron Radiation from MeV-Scale e

We present an apparatus for detection of cyclotron radiation yielding a frequency-based ß^{±} kinetic energy determination in the 5 keV to 2.1 MeV range, characteristic of nuclear ß decays. The cyclotron frequency of the radiating ß particles in a magnetic field is used to determine the ß energy precisely. Our work establishes the foundation to apply the cyclotron radiation emission spectroscopy (CRES) technique, developed by the Project 8 Collaboration, far beyond the 18-keV tritium endpoint region. We report initial measurements of ß^{-}'s from ^{6}He and ß^{+}'s from ^{19}Ne decays to demonstrate the broadband response of our detection system and assess potential systematic uncertainties for ß spectroscopy over the full (MeV) energy range. To our knowledge, this is the first direct observation of cyclotron radiation from individual highly relativistic ß's in a waveguide. This work establishes the application of CRES to a variety of nuclei, opening its reach to searches for new physics beyond the TeV scale via precision ß-decay measurements.

Impurity sublattice localization in ZnO revealed by Li marker diffusion.

Sublattice localization of impurities in compound semiconductors, e.g., ZnO, determines their electronic and optical action. Despite that the impurity position may be envisaged based on charge considerations, the actual localization is often unknown, limiting our understanding of the incorporation and possible doping mechanisms. In this study, we demonstrate that the preferential sublattice occupation for a number of impurities in ZnO can be revealed by monitoring Li diffusion. In particular, using ion implantation, the impurity incorporation into the Zn sublattice (holds for, B, Mg, P, Ag, Cd, and Sb) manifests in the formation of Li-depleted regions behind the implanted one, while Li pileups in the region of the implantation peaks for impurities residing on O sites, e.g., N. The behavior appears to be of general validity and the phenomena are explained in terms of the apparent surplus of Zn and O interstitials, related to the lattice localization of the impurities. Furthermore, Cd+O and Mg+O co-doping experiments revealed that implanted O atoms act as an efficient blocking "filter" for fast diffusing Zn interstitials.

Correlations between left ventricular mass and systolic blood pressure at rest and during maximal exercise in moderately hypertensive men.

We examined 87 men with moderate hypertension (diastolic blood pressure, DPB, greater than or equal to 95 and less than 110 mmHg) (mean age 45, range 22-64, years) with echocardiography and maximal ergometer bicycle test. Left ventricular mass index (LVMI) was calculated according to the Penn convention. Mean LVMI was 126 (60-210) g/m2. The maximal systolic blood pressure (SBP) during exercise was on average 217 (155-260) mmHg. Linear regression analysis revealed a significant correlation between LVMI and SBP at rest (r = 0.48, P less than 0.001) and during exercise (r = 0.39, P less than 0.001). Multiple regression analysis correcting for differences in age, cumulative work and cholesterol level revealed a significant correlation between LVMI and SBP at rest (t = 4.07, P less than 0.0001) and during exercise (t = 3.25, P = 0.002). Thus in patients with established, moderate hypertension exercise SBP is not more predictable for LVMI than is SBP at rest.

Validity of the ECG diagnosis of left ventricular hypertrophy in normotensive and moderately hypertensive men when using the echocardiographic assessment of left ventricular mass index as reference.

The diagnostic validity of ECG criteria for left ventricular hypertrophy (LVH) was assessed in 100 men aged 22-64 (mean 47) years with moderate hypertension (Group 1) and 95 age-matched normotensive men (Group 2) using echocardiographic recordings of LV mass index (MI) as reference. A diagnosis of LVH was made in subjects with LVMI greater than or equal to 125 g/m2. Mean LVMI was 126 +/- 34 g/m2 in Group 1 vs. 100 +/- g/m2 in Group 2 (P less than 0.001), and the prevalence of LVH was 48% and 11% respectively (P less than 0.001). The mean ECG voltage according to Sokolow-Lyon (S-L) was 28 +/- 8 mm in Group 1 and 27 +/- 7 mm in Group 2 (NS); with 19% having LVH in Group 1 and 14% in Group 2 (NS). Using the Cornell criterion Group 1 had on average 15 +/- 6 mm vs. 12 +/- 5 mm in Group 2 (P less than 0.001), but only two Group 1 patients had LVH. In Group 2 a significant negative correlation between age and S-L voltage was found (r = 0.33, P less than 0.001). LVMI was not correlated with any of the two voltage criteria using linear regression analysis whereas multiple regression analysis revealed a weak, but significant correlation between LVMI and S-L voltage in Group 1 (t = 2.06, P = 0.04). No subject had LV strain pattern or LVH according to the Romhilt Estes point score system. In the assessment of possible LVH in normal or moderately hypertensive men less than 65-70 years of age, ECG has limited value.

Towards a better life for the young workers. An education project in Malaysia.

PIP: Attention in this discussion focuses on Malaysia's education project, the Young Workers Community Education Project (YWCEP). At the Community Hall of Bayan Lepas, the YWCEP Center, about 60 local residents with more than half of them young industrial workers, are gathered for a half day forum on a Sunday morning. The subject is the current statewide industrial development program and its socioeconomic implications for the local community. The 2nd scene is at the Project Center on a Wednesday afternoon. 1 of 3 conversational English classes is in session. The 3rd scene is a bus carrying more than 30 young workers on a trip. The final scene is at a hostel provided by 1 of the factories for its workers. It is an opportunity for young workers to talk about their problems at work and to seek information on the ongoing activities sponsored by the Project. At first glance these programs and activities appear the same as those organized by similar service groups throughout industrial complexes in Malaysia over the past 5-10 years. What makes the YWCEP different and exciting is the approach to the problem of facilitating "A Better Life for Young Workers." The Project views the lives of the workers as a whole. This is reflected in the project design which attempts to relate the economic, the social, and the environmental dimensions of their lives in 1 integrated net of work modules. 1 basic goal of the Project is to facilitate individual participation in group activities, since this has been identified as a crucial need of the target group. The YWCEP is based on the conviction that the participants themselves must be involved at all levels of the Project operation, including planning and evaluation. The Project aims at being instrumental in bridging the gap between the young workers and the rest of the community. The YWCEP was conceived as a positive response to the many problems created by the rapid industrialization in the Bayan Lepas area of Penang in the early 1970s. The Federation of Family Planning Associations conducted a survey in 1974 to examine the situation with the objective of suggesting possible remedial action. In December 1975 a pilot community service project was launched, confirming the need for such a project. YWCEP was launched in 1977 and is now fully operational. It has gained the cooperation and respect of the young workers.^ieng

Myocardial scintigraphy with 99mtechnetium stannous pyrophosphate in patients with possible acute myocardial infarction.

Fifty-six patients with a preliminary diagnosis of possible acute myocardial infarction (AMI) were studied on the second or third day after onset of symptoms by 99mtechnetium stannous pyrophosphate myocardial imaging. The scintigraphy was positive in 25 (44.6%). The final clinical diagnoses upon discharge were: definite AMI in 11 with positive scintigraphy in 9 (82%), intermediate coronary syndrome (ICS) in 37 with positive scintigraphy in 15 (40.5%), postinfarction failure in 4 with positive scintigraphy in 1, no diagnosis of coronary heart disease in 4 patients with negative scintigraphy in all. Of the 37 patients with a final diagnosis of ICS, 25 were admitted to the Coronary Care Unit with chest pain as the only symptom. In this group the mean percentage increase in ASAT was significantly higher in 9 patients with positive scintigrams than in 16 with negative. It is therefore assumed that among patients with ICS, a positive scintigraphy may reflect a more serious myocardial injury than a negative scintigram. Of six patients with an acute tachyarrhythmia and ICS, scintigraphy was positive in the three with the most long-lasting or severe arrhythmmias. False negative scintigrams may be seen in some patients with definite AMI.

Effect of microbial inoculants on the nutritive value of corn silage for lactating dairy cows.

Two experiments were conducted to evaluate the effect of microbial inoculation on the composition and nutritive value of corn silage for lactating cows. In Experiment 1, forage was untreated or treated at ensiling with Pioneer 1174 or Ecosyl silage inoculants. Forage was offered for free choice consumption, and concentrate was fed by a computerized feeder. Treatment with 1174 inoculant had little effect on silage composition and no effect on cow performance. Silage treated with Ecosyl inoculant had greater lactic acid content, but also greater acetic acid and ammonia N contents. Production of 3.5% FCM was greatest from cows fed silage treated with Ecosyl. In Experiment 2, silage was untreated or treated with Ecosyl and fed in a TMR. Inoculation had no effect on silage composition but increased 3.5% FCM production and DMI as length of time on treatment increased. Microbial inoculation can improve the nutritive value of corn silage for lactating cows even if changes in fermentation end products are minimal.

Changes in left ventricular dimensions and systolic function in 100 mildly hypertensive men during one year's treatment with atenolol vs. hydrochlorothiazide and amiloride (Moduretic): a double-blind, randomized study.

In a randomized double-blind study to compare the effect of atenolol vs. hydrochlorothiazide and amiloride (Moduretic) on left ventricular dimensions and systolic function, 100 hypertensive men were followed up during 1 year of treatment, 50 subjects being randomized to each drug. Echocardiography was performed at baseline, and after 3 and 12 months of treatment. A significant reduction in left ventricular mass with atenolol was paralleled by a decrease in left ventricular wall thickness and an increase in stroke volume. A similar reduction of left ventricular mass with Moduretic without a change in relative wall thickness and a decrease in stroke volume was observed. Cardiac output decreased in both groups.

Doppler ultrasound in mitral stenosis. Assessment of pressure gradient and atrioventricular pressure half-time.

In 16 patients with mitral stenosis (MS), alone or in combination with either mitral insufficiency (2 pats.) or aortic valve disease (3 pats.), the mean diastolic pressure gradients across the mitral valve calculated by Doppler ultrasound were significantly correlated to the catheterization data. The average mean pressure drop by Doppler was 11.8 mmHg and by catheterization at rest 16.7 mmHg. A significant correlation between gradients was also found in 5 patients who exercised supine on a bicycle. Atrioventricular pressure half-time (T1/2), i.e. the time during which the pressure drops from the peak value to half of its initial value by the Doppler technique, was significantly correlated to mitral valve area (MVA) determined from catheterization data. Increasing T1/2 reflected decreasing MVA. It is concluded that Doppler ultrasound is a useful method in the evaluation of patients with MS.

Detection of mitral regurgitation by Doppler ultrasound. A comparison with left ventricular angiography.

Sixty-four patients with various heart diseases were evaluated for mitral regurgitation (MR) by left ventricular angiography and pulsed Doppler ultrasound within 2-3 days. Adequate Doppler recordings were obtained from 60 patients. The sensitivity of Doppler in detecting MR was 94%, specificity 90% and predictive value for a positive and a negative Doppler examination 90 and 93%, respectively. Two of the 3 false positive Doppler recordings were from patients with coronary heart disease, ischemic papillary muscle dysfunction may have caused MR inconsistently. Two false negative Doppler recordings may be related to problems in placing the ultrasonic sample volume at the systolic retrograde blood stream in the left atrial cavity. It is concluded that pulsed Doppler ultrasound, being a transcutaneous, non-invasive method, is a valuable tool in detecting MR. So far, we have not been able to quantitate the regurgitation.

Is left ventricular mass in apparently healthy, normotensive men correlated to maximal blood pressure during exercise?

In 95 apparently healthy normotensive men aged 21-69 (mean 44) years with supine blood pressure (BP) less than 150/90 mmHg when less than 50 years, and less than 160/95 when greater than or equal to 50 years of age, left ventricular mass (LVM) was measured by M-mode echocardiography and related to maximal BP during a symptom-limited ergometer bicycle test. Mean LVM was 195 (+/- 43) g and LVM index (I) 101 (+/- 20) g m-2 body surface area (BSA). The subjects were subdivided into two groups: Group 1 = 28 subjects (29%) with LVM greater than or equal to 220 g, and Group 2 = 67 subjects (71%) with LVM less than 220 g. Group 1 had a slightly larger BSA (P less than 0.05), weight (P less than 0.05) and resting systolic BP (P less than 0.05). A higher prevalence of smokers (P less than 0.01) and serum cholesterol levels (P less than 0.05) were also noted among Group 1 subjects, who had a higher maximal systolic BP during exercise (P less than 0.0001). Using linear regression analysis, significant positive correlations were observed between LVM and systolic BP at rest (r = 0.20, P less than 0.05), and maximal exercise systolic BP (r = 0.32, P less than 0.001). When correcting for differences in age, weight, body surface area, physical performance, smoking and hours of exercise per week, multiple regression analysis revealed a significant between LVM and maximal systolic BP (t = 2.38, P = 0.020, Partial F = 5.64).(ABSTRACT TRUNCATED AT 250 WORDS)

M-mode echocardiographic findings in apparently healthy, non-athletic Norwegians aged 20-70 years. Influence of age, sex and body surface area.

In order to assess M-mode echocardiographic recordings in a normal Norwegian population, 190 apparently healthy subjects (95 women and 95 men) aged 21-69 years were examined with an Irex Meridian system. Measurements were performed according to criteria recommended by the American Society of Echocardiography. Absolute values for all parameters except for left ventricular (LV) shortening fraction (SF) were greater in men (P less than 0.001). When corrected for body surface area (BSA), the differences between the two genders were far less pronounced. Women had greater left atrium (LA) (P less than 0.01) and LV end-diastolic diameter (EDD) (P less than 0.001), whereas the interventricular septum in end-diastole (IVS-ED) (P less than 0.05) and LV posterior wall (PW) in ED (P less than 0.001) were thicker in men. Only weak correlations between age and the various echocardiographic parameters with r-values less than or equal to 0.30 were observed. It is recommended that BSA corrected values should be preferred since the differences between men and women are negligible. When absolute values are used, different normal ranges for both sexes should be applied.

Self-poisoning and moon phases in Oslo.

During 1980 the relation between the moon phases and 1187 cases of self-poisonings in Oslo was studied. In contrast to a previous report from India no significant correlation was found between the full moon and self-poisoning. The aetiology of self-poisonings in western countries is rather more complex than to be explained by speculative 'human tidal waves'.

Clinical course in acute self-poisonings: a prospective study of 1125 consecutively hospitalised adults.

The clinical course in an unselected group of 1125 consecutively hospitalised self-poisonings was studied during 1 year in Oslo. Mortality was 0.5%, but only 0.3% in those admitted without cardiac and respiratory arrest. Mortality among those in grade IV coma was 4.2%. The deepest comas (grade III or IV) occurred in 25.1% of the admissions with a mean duration of the coma of 5.8 h (range 1-80). Complications occurred in 21.7% of the admissions and 6.9% suffered more than one complication of which the most frequent were respiratory depression (13.5%), hypotension (5.3%), pneumonia (4.4%), and hypothermia (1.6%). The complication rate was highest in poisonings with opiates (60.7%), meprobamate (37.5%) and antihistamines (30.0%). Arrhythmias and respiratory depression were closely associated with poisonings with antidepressants and opiates, respectively. Owing to frequent polydrug overdoses it was difficult to associate other complications with other main toxic agents. Administration of antidotes (20.6%), cuffed intubation (4.4%) and forced alkaline diuresis (3.4%) were the most frequent special therapeutic measures taken. The change in pattern of self-poisonings in Oslo focuses on antidote therapy and intensive care, especially outside hospital, but limits the need for haemodialysis and haemoperfusion which were performed in only 1.0% of the admissions.

A prospective study of 1212 cases of acute poisoning: general epidemiology.

A prospective multicentre study of all acute poisonings among adults admitted to hospital (n = 1145) or dying outside hospital (n = 67) in Oslo was performed during 1980. Of the 1212 episodes, 98.3% were self-poisonings, giving an annual incidence of 2.8 per 1000 inhabitants (0/00), 3.1 0/00 in males and 2.6 0/00 in females. The main toxic agents among the self-poisoned patients were ethanol (19.7%), benzodiazepines (17.8%), opiates (14.9%), neuroleptics (10.4%) and antidepressants (9.3%). In 58.9% of the episodes more than one toxic agent was taken. Abuse among the self-poisoned patients was significantly (p less than 0.005) more common among males than females (64.2 v. 34.5%). The rate of suicide attempts was significantly (p less than 0.005) higher among females than males (20.2 v. 12.9%), females showing increasing rate with age. However, when excluding abusers the rate of suicide attempts was similar in both sexes (27.6 v. 25.0%). Compared to a reference population self-poisonings were most common in the lower middle and the lowest social classes. Patients in these social classes, however, showed a lower rate of suicide attempts than those in the two highest social classes. Overall mortality was 6.0% (n = 73), but 91.8% of all deaths occurred outside hospital indicating the importance of including these figures when self-poisonings are studied.