Promoting Smoke-Free Homes: A Novel Behavioral Intervention Using Real-Time Audio-Visual Feedback on Airborne Particle Levels

Interventions are needed to protect the health of children who live with smokers. We pilot-tested a real-time intervention for promoting behavior change in homes that reduces second hand tobacco smoke (SHS) levels. The intervention uses a monitor and feedback system to provide immediate auditory and visual signals triggered at defined thresholds of fine particle concentration. Dynamic graphs of real-time particle levels are also shown on a computer screen. We experimentally evaluated the system, field-tested it in homes with smokers, and conducted focus groups to obtain general opinions. Laboratory tests of the monitor demonstrated SHS sensitivity, stability, precision equivalent to at least 1 µg/m³, and low noise. A linear relationship (R² = 0.98) was observed between the monitor and average SHS mass concentrations up to 150 µg/m³. Focus groups and interviews with intervention participants showed in-home use to be acceptable and feasible. The intervention was evaluated in 3 homes with combined baseline and intervention periods lasting 9 to 15 full days. Two families modified their behavior by opening windows or doors, smoking outdoors, or smoking less. We observed evidence of lower SHS levels in these homes. The remaining household voiced reluctance to changing their smoking activity and did not exhibit lower SHS levels in main smoking areas or clear behavior change; however, family members expressed receptivity to smoking outdoors. This study established the feasibility of the real-time intervention, laying the groundwork for controlled trials with larger sample sizes. Visual and auditory cues may prompt family members to take immediate action to reduce SHS levels. Dynamic graphs of SHS levels may help families make decisions about specific mitigation approaches.     

Differentials of fertility between polygynous and monogamous marriages in rural Bangladesh

This paper discusses polygynous marriages in rural Bangladesh, using marital status and birth registration data from the Demographic Surveillance System (DSS) of the International Center for Diarrheal Disease Research, for the period 1975-79. Of all the marriages recorded during this period about 5% were polygynous. To identify the women polygynously married, 1974 census data of the DSS area were used. The difference in age at marriage between the polygynous groom and his subsequent wife was 15 years on average. The socioeconomic indicators studied were education, occupation and area of dwelling space. In general, these indicators between women in monogamous marriages were significantly higher than between the women in polygynous unions. During the period 1976-79, 863 polygynous marriages were recorded (4.9% of all marriages in the study area). Polygynous marriages were found to be less frequent among men with 2ndary and higher levels of education. The highest proportion of polygynous marriages occurred among husbands with no schooling or Koranic education. The general fertility rate of women in monogamous marriages was significantly higher than for women in polygynous marriages, overall and in all age groups except 20-24. During the period 1975-79, the mean number of liveborn children for monogamous women was higher than that of polygynous women.     

A mass spectrometric technique for detecting and identifying by-products in the synthesis of peptides

The utility of a new mass spectrometric technique for detecting and identifying peptide by-products produced in the synthesis of peptides is demonstrated. The technique involves three sequential steps: (1) practically nondestructive 252Cf plasma desorption mass spectrometric analysis of monolayer amounts of the peptide(s) of interest bound to a thin layer of nitrocellulose; (2) enzyme-catalyzed microscale chemical reaction of the surface-bound peptide(s) to produce structurally informative hydrolysis products; (3) plasma desorption mass spectrometric analysis of these hydrolysis products. The first step determines the presence and the molecular weights of unwanted by-products resulting from errors or incomplete reactions during synthesis. The subsequent two steps provide information on the precise location in the peptides where errors have occurred. In the present paper, the technique is applied to an investigation of unwanted peptide by-products associated with the use of tryptophan during stepwise solid-phase peptide synthesis. Synthetic preparations of melittin and [Bpa-8]dynorphin A (1-17) were each found to contain a major impurity with molecular weight 28 Da higher than that of the desired product. The impurity in the melittin preparation, in which the final deprotection step involved the high-low HF procedure, was shown to result from incomplete removal of the formyl group from Trp-19. On the other hand, the impurity in the [Bpa-8]dynorphin A (1-17) preparation, where the removal of the formyl group from Trp-14 was carried out using piperidine, was shown to result from migration of the formyl group to Lys-11 or Lys-13.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bacterial cellulases and saccharification of lignocellulosic materials

Five locally isolated bacterial strains produced extracellular cellulase enzymes, primarily CMCase, when grown on different natural and commercial cellulosic substrates. Extracellular CMCase and avicelase activity was higher with the strain CLS-32, a Cytophaga sp., compared to four other strains. The whole-cell preparations of these isolates were found to saccharify cellulosic substrates to reducing sugars. Maximum release of reducing sugar (5.75 mg ml⁻¹) was obtained with CLS-32 using sugar cane bagasse as growth and hydrolysis substrates.     

Organogenesis and plant formation from cotyledon explant cultures of wild turnip rape (Brassica tournefortii L.)

Cotyledon explants of Brassica tournefortii L. were excised from germinated seedlings and cultured on Murashige & Skoog's [6] basal medium supplemented with various combinations of cytokinins and auxins, Both cytokinin and auxin were required for induction of shoot organogenesis. Of the three cytokinins tested (in combination with a low concentration of IAA), kinetin was found to be the best for shoot regeneration. On this medium, cotyledonary explants invariably underwent callusing followed by multiple shoot formation. NAA in combination with any of the three cytokinins yielded a reduced number of shoots or none, but favoured good callus growth. Callus so produced also regenerated shoots when subcultured on media containing high concentration of KIN or ZEA and low concentration of IAA. Shoots were rooted during prolonged incubation on the same medium or on MS medium free of growth regulators. Mature plants were grown in the greenhouse.     

Luteolytic action of two antiprogestational agents (RU-38486 and ZK-98734) in the rat

RU-38486 or ZK-98734 treatment (3 mg/day, s.c.) to intact or hysterectomized adult female rats on Days 5-7 post coitum induced changes characteristic of luteolysis. Ultrastructurally, the luteal cells exhibited an extensive vacuolization of the cytoplasm and perinuclear areas, degeneration of mitochondrial cristae, massive accumulation of lipid droplets, increase in number of lysosome like granules and heterochromatinization of the nucleus. In general, RU-38486 induced more marked degeneration of the luteal cells than did ZK-98734. There was also a significant decrease in peripheral plasma progesterone concentrations in treated rats. We suggest that these antiprogestagens act via inhibition of luteal function in addition to their antagonism at the uterine progesterone receptor level.     

Studies on the agglutinating activity of pancreatic extracts and its relevance to function

Summary Agglutination of washed rabbit erythrocytes caused by pancreatic acinar cell extract was inhibited by glucose, maltose and cellobiose. Process of elimination and purification divulged that the acinar cell enzyme -amylase was responsible for attributing the agglutinin activity. Assay of enzyme and agglutinin activity data of different fractions of re-purified -amylase eluted from HPLC column showed that both the activity resides in the same fraction which suggests that the enzyme binds to the glucosyl residues of the rabbit erythrocytes via the carbohydrate binding/catalytic sites. Similar properties of other glycosidases were also noted.     

Nutritional status and age at secondary sterility in rural Bangladesh

In a prospective study of 2324 women in Matlab, Bangladesh, the occurrence of primary and 2ndary sterility by age groups was examined. The results were related to the nutritional status of the women, as assessed by measurements of height, weight, arm circumference and ponderal index. Approximately 98% of the women who were in the age group 15-19 were found to be fertile. This proportion decreases gradually up to the age group 30-34 years and thereafter declines sharply, reaching only 31% in the age group 45-49. The height data suggest no significant difference in the age pattern of sterility among the 3 groups of women, although there is a slight tendency that women who were less tall reached menopause earlier than the other 2 groups. Variations in weight are more conspicuous than in height. There is the suggestion that thinner women may experience an earlier menopause. Women having an arm circumference less than 21 cm, between 21-22 cm, and 23 cm and above, and currently aged 17 years, have an expected fertile life estimated at 25.0, 25.8, and 26.6 years respectively. The median ages at sterility were 42.8, 44.0, and 44.3 years respectively with a difference of about 1 year between the 1st 2 groups. This suggests that sterility occurs earlier among the thinner women. Since detailed investigation of nutritional status was not possible, it was assessed by anthropometry. There was strong evidence that nutritional status is an important factor in the estimated age at sterility, with thinner women experiencing an earlier menopause. Although it is impossible to measure the onset of sterility, one can obtain a minimum estimate of it from the age-specific distribution of the proportion of women who have not produced a child for 5 years of being at risk.     

Hydrogen peroxide metabolism as an index of water stress tolerance in jute

Two species of jute plants Corchorus capsularis L. (cv. JRC 212) and C. olitorius L. (cv. JRO 632) were subjected to water stress for 2 and 4 days by withholding water. The relative water content (RWC) decreased in both plants under water stress but to a greater extent in C. olitorius . The C. olitorius seedlings also showed greater membrane injury than C. capsularis seedlings under water stress as was evident from injury index data. Water stress increased glycolate oxidase (EC 1.1.3.1.) activity more in C. olitorius than in C. capsularis . The activity of superoxide dismutase (SOD, EC 1.15.1.1.) and catalase (EC 1.11.1.6.) decreased under water stress and their decrease was higher in C. olitorius than in C capsularis . The level of hydrogen peroxide and lipid peroxidation also increased in both plants under water stress and the increase was higher in C. olitorius than in C. capsularis seedlings. Under comparable external water stress, C. capsularis seedlings showed lower membrane damage, lower H₂O₂ accumulation and lower lipid peroxidation than C. olilorius which may be taken as indicative of higher water stress tolerance capacity of the former.