Seasonal patterns of deaths in Matlab, Bangladesh

BACKGROUND: Deaths exhibit a seasonal pattern in most parts of the world. Analyses of deaths for the years 1972-1974 from the vital registration system of Matlab, Bangladesh, published in this journal 17 years ago, showed sinusoidal seasonal patterns. As death rates have declined in other nations, the seasonal pattern is attenuated. Death rates have declined substantially in Bangladesh in the past two decades. Thus, the present study examines monthly counts of deaths from Matlab data for a period 15 years later and tests the hypothesis of a decrease or shift in seasonality over time. METHODS: Trigonometric regression models were fit to monthly data by age and cause of death from the Matlab vital registration system for the years 1982-1990. A total of 20,328 death records were available for analyses. RESULTS: In the recent period significant sinusoidal seasonal patterns are found in all but one of the age and cause of death groups. Total deaths peak in the winter as do neonatal deaths but post-neonatal and child deaths are maximum in April and July respectively. Among cause groups, injury deaths (mostly attributed to drowning) show the greatest seasonal swing. The time of peak has only shifted for one age group--neonates--since the 1972-1974 period. The magnitude of the seasonal swing has declined significantly only for the neonatal age group and injury cause of death group. CONCLUSION: Marked seasonal patterns of deaths persist in the Matlab area of Bangladesh even as the level of mortality has declined.     

Gender preference and birth spacing in Matlab, Bangladesh

Gender preference, particularly son preference, is believed to sustain high fertility in many Asian countries, but previous research shows unclear effects. We examine and compare gender-preference effects on fertility in two otherwise comparable populations in Bangladesh that differ markedly in their access to and use of contraception. We expect, and find, stronger effects of gender preference in the population that has more access to contraception and higher levels of contraceptive use. Thus gender preference may emerge as a significant barrier to further national family planning efforts in Bangladesh. We find that if a woman has at least one daughter, the risk of a subsequent birth is related negatively to the number of sons. Women with no daughters also experience a higher risk of having a subsequent birth; this finding suggests that there is also some preference for daughters. Son preference is strong in both the early and later stages of family formation, but women also want to have at least one daughter after having several sons.     

Uptake of contraception during postpartum amenorrhoea: understandings and preferences of poor, urban women in Bangladesh

In urban Bangladesh, as in many other settings, an immediate postpartum family planning strategy prevails, where providers seek to promote and provide contraception at 40-45 days following birth to women regardless of their breastfeeding or menstrual status. Despite such practices, the majority of women choose to delay the initiation of contraception until menses resumes, often several months after birth. The present paper seeks to explain this discrepancy by describing poor, urban women's understandings regarding the chances of conception and the risks associated with contraceptive use in the postpartum period. Findings from in-depth interviews reveal that the majority of women perceive no personal risk of pregnancy during amenorrhoea, though most do not recognise an association between this diminished risk of conception and breastfeeding. In addition, the data illustrate that women are primarily concerned with their own and their newly born child's health and well-being in the period following childbirth, both of which are perceived to be extremely vulnerable. These perceptions, plus an understanding that modern methods of contraception are "strong" and potentially damaging to the health, mean that the majority of women are reluctant to adopt family planning methods soon after birth, particularly during postpartum amenorrhoea. The paper advocates that, since breastfeeding affords good protection against pregnancy for six to nine months following birth, efforts should be made to actively incorporate lactational amenorrhoea into postpartum family planning strategies in Bangladesh. Recommendations are also made for ways in which women may be encouraged to adopt contraception during amenorrhoea beyond the period of high natural protection. The paper highlights the importance of taking the client's perspective into consideration in attempts to improve the quality and effectiveness of family planning programmes.     

Factors affecting the use of folic acid supplements in pregnant women in Glasgow

BACKGROUND: Use of folic acid supplements preconception, and during the first trimester, is associated with a reduced incidence of first and subsequent neural tube defects. The Department of Health guidelines recommend the use of folic acid supplements by all women planning a pregnancy. AIM: To ascertain the proportion using folic acid supplements and the factors affecting their use. METHOD: Questionnaires were distributed postpartum to the 515 women who delivered normal babies in three maternity units in Glasgow over a four-week period. RESULTS: Forms were completed by 487 (95%) women. Only 57% took supplements at some point during their pregnancy, and only 21% took them before conception. Failure to take supplements was significantly associated with unplanned pregnancy, younger age, and previous pregnancies. Lack of awareness of the potential benefits associated with folic acid use was the commonest reason cited by women for not taking supplements. CONCLUSIONS: Increased health education through health care professionals and mass media campaigns can improve awareness and thereby increase the use of supplements in planned pregnancies. However, 42% of women in our study had unplanned pregnancies. Intake of folic acid supplements in this group can only be increased by improvements in dietary intake within the population as a whole, and by fortification of commonly ingested foods.     

Duration of use of intrauterine contraception

Data from cytological examination of smears from the surface of IUD's were studied in 310 women; 94 of them had used IUDs up to 1 year, 150 from 1 to 3 years and 66 for 3 years or more. The study revealed a membrane isolated from the endometrium, consisting of bloodcells (red corpuscles and dead leucocytes), mature squamous and glandular epithelium, amorphous protein mass, fibrin filaments, fibroblasts and multinuclear giant cells. None of these smears revealed any atypical cells. An examination of 116 washings from the surface of removed IUD's was done. Biopsies were performed on the endometrium of 154 women; the morphological picture was identical. In several cases a local, nonspecific inflammation of the endometrium was detected. There was no clinical disorder. Intrauterine devices should not be used without interruption for more than 6 or 7 years, and the interruptions should last at least 2 or 3 months. Regular, careful examinations should be performed on women using intrauterine devices.     

Duration of protective immunity conferred by maternal tetanus toxoid immunization: further evidence from Matlab, Bangladesh

OBJECTIVES: Although maternal tetanus immunization has been shown to be highly effective in the prevention of neonatal tetanus, unresolved questions remain concerning the required minimum number of doses and the resulting duration of effective immunity. This study examined the duration of effective immunity against neonatal tetanus provided by maternal tetanus immunization. METHODS: A randomized, double-blind cholera vaccine trial of 41,571 children and nonpregnant adult women carried out in 1974 in the Matlab comparison area of rural Bangladesh provided a unique opportunity to address dose and immunity issues. RESULTS: Children of women who received either 1 or 2 injections of tetanus toxoid experienced 4- to 14-day mortality levels consistently lower than those of children of unimmunized mothers. Analysis of neonatal-tetanus-related mortality showed that 2 injections of tetanus toxoid provided significant protection for subsequent durations of up to 12 or 13 years. CONCLUSIONS: The data demonstrate that a limited-dose regimen of maternal tetanus toxoid provides significant and extended protection against the risk of neonatal tetanus death.     

Factors affecting high-density lipoproteins

Although it is well established that a low-circulating level of high-density lipoprotein (HDL) cholesterol is strongly associated with the likelihood of developing atherosclerotic coronary heart disease (CHD), the causal nature of this association has not been shown. Low levels of HDL cholesterol frequently are associated with other CHD risk factors, whose correction, often by hygienic means, may reduce CHD risk with minimal risk of adverse side-effects. However, other recommended hygienic interventions may lower HDL cholesterol levels. Specific safe and effective drugs for correcting a low HDL cholesterol level are not available and the potential value of specific pharmacologic treatment of this condition in the treatment or prevention of CHD remains unproven. Thus, while HDL measurement should be incorporated routinely in risk-assessment, intervention efforts should focus primarily on lowering low-density lipoprotein cholesterol.     

影响光面爆破效果的因素分析

对光面爆破原理和影响因素进行了分析,介绍了光面爆破的方法、光面爆破参数的选择和光面爆破的优点,说明了采用光面爆破的必要性.     

The use of behavioral methods of contraception in women seeking abortion

AIMS: To determine the extent to which behavioural methods, used alone or with other methods of contraception, contribute to contraceptive failure in women seeking termination of pregnancy. METHOD: A clinical audit was conducted of the use of behavioural methods of contraception, in 1342 women attending the Parkview Clinic for termination of pregnancy, over a four year period 1992-6. The information was obtained through standard interview and patient records. RESULTS: The women seen were representative of New Zealand women undergoing termination of pregnancy. Approximately one third of women (34.9%) used one or more behavioural methods in the month prior to conception. The two most common methods were periodic abstinence and coitus interruptus, both used by approximately 17%. Other methods used less frequently and not solely for contraceptive purposes, were cleansing of the vagina and breastfeeding. Pacific Island and Asian women were more likely to use behavioural methods than European and Maori women. Many women (45.6%) using behavioural methods also used other methods of contraception, especially the condom. CONCLUSIONS: Behavioural methods were found more commonly than previously reported. Greater understanding of the use of behavioural methods will assist in the implementation of preventive programmes to reduce the number of terminations.     

Factors affecting alkali jarosite precipitation

Several factors affecting the precipitation of the alkali jarosites (sodium jarosite, potassium jarosite, rubidium jarosite, and ammonium jarosite) have been studied systematically using sodium jarosite as the model. The pH of the reacting solution exercises a major influence on the amount of jarosite formed, but has little effect on the composition of the washed product. Higher temperatures significantly increase the yield and slightly raise the alkali content of the jarosites. The yield and alkali content both increase greatly with the alkali concentration to about twice the stoichiometric requirement but, thereafter, remain nearly constant. At 97 °C, the amount of product increases with longer retention times to about 15 hours, but more prolonged reaction times are without significant effect on the amount or composition of the jarosite. Factors such as the presence of seed or ionic strength have little effect on the yield or jarosite composition. The amount of precipitate augments directly as the iron concentration of the solution increases, but the product composition is nearly independent of this variable. A significant degree of agitation is necessary to suspend the product and to prevent the jarosite from coating the apparatus with correspondingly small yields. Once the product is adequately suspended, however, further agitation is without significant effect. The partitioning of alkali ions during jarosite precipitation was ascertained for K:Na, Na:NH₄, K:NH₄, and K:Rb. Potassium jarosite is the most stable of the alkali jarosites and the stability falls systematically for lighter or heavier congeners; ammonium jarosite is slightly more stable than the sodium analogue. Complete solid solubility among the various alkali jarosite-type compounds was established.     

Factors affecting bone graft incorporation

Successful graft incorporation requires that an appropriate match be made among the biologic activity of a bone graft, the condition of the perigraft environment, and the mechanical environment. The authors have studied, in a wide variety of animal models, the factors that affect the main components of bone graft incorporation: revascularization, new bone formation, and host-graft union. The principal determinant of the rate, pattern, and amount of revascularization is the presence or absence of a vascular pedicle. The nonvascularized bone graft is entirely dependent on the surrounding tissue for its revascularization, which results in a noticeable delay in vessel ingrowth. The principal determinant of the rate and amount of new bone formation on, in, or about a bone graft is the presence or absence of living, histocompatible, committed bone-forming cells. When living cells are not part of the graft at the time of implantation, the cells that form new bone are derived from host tissues, and new bone formation is delayed. The principal determinants of host-graft union are stability of the construct and contact between host bone and the graft. Factors that slow or inhibit all of these processes are reduction of the biologic activity of the graft by freezing or some other treatment, histocompatibility antigen disparities between donor and recipient, mechanical instability between the graft and the perigraft environment, and local and systemic interference with the biologic activity of the graft and surrounding tissue, for example, by irradiation or the administration of cisplatin. The task of the clinician who does a bone grafting procedure is to choose the right graft or combination of grafts for the biologic and mechanical environment into which the graft will be placed.     

Factors affecting lead jarosite formation

The importance of lead jarosite in hydrometallurgical processing and the factors affecting its formation in both the slow addition and autoclave synthesis techniques are discussed. In the slow addition method the principal factors are the amount and rate of delivery of soluble lead to the hot ferric sulphate solution; high temperatures and good agitation are also essential to avoid the formation of PbSO₄. The key step in the autoclave synthesis process is the selective removal of residual PbSO⁴ from the reaction product and methods of accomplishing this are described. The major factors affecting the autoclave synthesis of lead jarosite are the ratio of $\text{PbSO}{}_4\text{Fe}{}^{\mathrm{3+}}$, acid concentration and the ionic strength of the solution. Time, temperature, degree of agitation and seeding all affect the reaction but to a lesser degree. The principal techniques identified to suppress lead jarosite formation were high acidity (> 0.3 M H₂SO₄ or the presence of substantial quantities (> 0.3 M) of other jarosite formers such as K₂SO₄. Lead jarosites containing more than 16% Pb were produced and X-ray diffraction data for such material are presented.     

Factors affecting callus distraction in limb lengthening

Factors affecting the process of callus distraction in limb lengthening include the type of osteotomy, timing and rate of distraction, and stability of fixation. Thirty-two rabbits were studied to evaluate the reliability of transverse osteotomy and delayed distraction and to examine the appropriate rates of distraction. Rabbit tibiae were osteotomized subperiosteally and were subjected to slow distraction using a rigid monolateral external fixator. There was a ten-day waiting period before distraction. The animals were divided into three groups according to the rate of distraction (0.35 mm/12 hours, 0.7 mm/12 hours, 1.4 mm/12 hours). The process of callus formation was monitored by soft x-ray. The reliability of delayed distraction after transverse osteotomy was demonstrated by microangiographic study. Even though intramedullar vessels were interrupted by osteotomy at surgery, blood circulation recovered during the waiting period before distraction. Bone lengthening was successful when distraction was carried out at rates of 0.35 mm/12 hours or 0.7 mm/12 hours. The callus filling a distraction gap showed a characteristic zone structure, i.e., one central radiolucent zone and two adjacent sclerotic zones. Microangiographic study demonstrated the continuity of blood vessels under these rates of distraction. Based on the results of these experiments and clinical experiences on 180 bone lengthenings, the authors believe that a waiting period after osteotomy is more practical than achieving immediate distraction after uncertain corticotomy.     

Factors affecting discharge time in adult outpatients

Discharge time (total recovery time) is one determinant of the overall cost of outpatient surgery. We performed this study to determine what factors affect discharge time. Details regarding patients, anesthesia, surgery, and recovery were recorded prospectively for 1088 adult patients undergoing ambulatory surgery over an 8-mo period. The contribution of factors to variability in the discharge time was assessed by using multivariate linear regression analysis. In the last 4 mo of the study, nurses indicated the causes of discharge delays > or =50 min in Phase 1 or > or =70 min in Phase 2 recovery. When all anesthetic techniques were included, anesthetic technique was the most important determinant of discharge time (R2 = 0.10-0.15; P = 0.001), followed by the Phase 2 nurse. After general anesthesia, the Phase 2 nurse was the most important factor (R2 = 0.13; P = 0.01-0.001). In women, the choice of general anesthetic drugs was significant (R2 = 0.04; P = 0.002). The three most common medical causes of delay were pain, drowsiness, and nausea/vomiting. System factors were the foremost cause of Phase 2 delays (41%), with lack of immediate availability of an escort accounting for 53% of system-related delays. We conclude that efforts to shorten discharge time would best be directed at improving nursing efficiency; ensuring availability of an escort for the patient; and preventing postoperative pain, drowsiness, and emetic symptoms. The selection of anesthetic technique and anesthetic drug seems to be of selective importance in determining discharge time depending on patient gender and type of surgery. IMPLICATIONS: The relative importance of anesthetic and nonanesthetic factors were evaluated as determinants of discharge time after ambulatory surgery. Postoperative nursing care was the single most important factor after general anesthesia; anesthetic drugs, anesthetic technique, and prevention of pain and emetic symptoms were of selective importance depending on patient gender and type of surgery.     

Factors affecting C3 in intestinal schistosomiasis

Complement component C3 was investigated in sera of a group of schistosomal patients free from obvious nephritis. C3 was studied in relation to S. mansoni egg count, presence of HBsAg, and liver functions. C3 level was low in schistosomal patients than normal individuals. Levels were low in both HBsAg --ve and HBsAG +ve schistosomal patients. No significant difference was found between HBsAg --ve and HBsAg +ve in one hand, and between patients with egg counts more than 400 and those with egg counts less than 400 eggs/1 gr as regards level of C3 on the other hand. Presence of ascites did not affect C3 concentration. Positive correlation was found with Serum albumin, but not with prothrombin concentration serum alkaline phosphatase or serum transaminases.     

Factors affecting the biodegradation of toluene in soil

The biodegradation of toluene in soil microcosms was examined in order to identify the physical, chemical, and biological factors which determine the fate and lifetime of organic chemicals in soils. Toluene degradation rates were proportional to the initial substrate concentration and these rates reached a maximum at a concentration of 200 micrograms/g. No degradation occurred above this concentration presumably due to the toxicity of the hydrocarbon to the soil microorganisms. Small differences were observed in the degradation rates in soils at different moisture content. However, the availability of water in soil appeared to limit toluene degradation only at a very low water content. The lifetime of toluene in soil was also related to the initial level and activity of the soil microorganisms. Toluene was metabolized rapidly in those soils which initially contained high levels of degrading microorganisms. Furthermore, exposure of the soil to toluene resulted in an increase in the number of degrading organisms. The lack of inorganic nutrients such as nitrogen prevented complete degradation of toluene in a clay soil which contained high levels of degrading microorganisms. The biodegradation of organic chemicals in soil is not an intrinsic property of the molecule and cannot be predicted without first delineating the environment in which it is found. The biodegradation of a compound is defined by the biological, physical, and chemical characteristics of the soil environment. The lifetime of a chemical in soil results from a combination of all three of these parameters.     

Factors affecting employee selection in two cultures.

4 samples—100 Illinois and 100 Greek students, 32 Illinois and 20 Greek personnel directors (PDs)—were asked to respond to a structured questionnaire which permitted the computation of the relative weights that would be given to various characteristics (competence, age, sex, race, religion, sociability, and wealth) by these people, if they were hiring employees for various levels of jobs in the accounting and finance department of a company. The responses of the 4 samples were similar. However, the American PDs gave more weight to race and the Greek PDs more weight to age than did the other samples. The students differed significantly from the PDs; in both cultures, the students gave larger weights to competence than did the personnel directors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)