11 resultados para Attributable risks

em Helda - Digital Repository of University of Helsinki


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Sprouting of fast-growing broad-leaved trees causes problems in young coniferous stands, under power transmission lines and along roads and railways. Public opinion and the Finnish Forest Certification System oppose the use of chemical herbicides to control sprouting, which means that most areas with problems rely on mechanical cutting. However, cutting is a poor control method for many broad-leaved species because the removal of leaders can stimulate the sprouting of side branches and cut stumps quickly re-sprout. In order to be effective, cutting must be carried out frequently but each cut increases the costs, making this control method increasingly difficult and expensive once begun. As such, alternative methods for sprout control that are both effective and environmentally sound represent a continuing challenge to managers and research biologists. Using biological control agents to prevent sprouting has been given serious consideration recently. Dutch and Canadian researchers have demonstrated the potential of the white-rot fungus Chondrostereum purpureum (Pers. ex Fr.) Pouzar as a control agent of stump sprouting in many hardwoods. These findings have focused the attention of the Finnish forestry community on the utilization of C. purpureum for biocontrol purposes. Primarily, this study sought determines the efficacy of native C. purpureum as an inhibitor of birch stump sprouting in Finland and to clarify its mode of action. Additionally, genotypic variation in Finnish C. purpureum was examined and the environmental risks posed by a biocontrol program using this fungus were assessed. Experimental results of the study demonstrated that C. purpureum clearly affects the sprouting of birch: both the frequency of living stumps and the number of living sprouts per stump were effectively reduced by the treatment. However, the treatment had no effect on the maximum height of new sprouts. There were clear differences among fungal isolates in preventing sprouting and those that possessed high oxidative activities as measured in the laboratory inhibited sprouting most efficiently in the field. The most effective treatment time during the growing season was in early and mid summer (May July). Genetic diversity in Nordic and Baltic populations of C. purpureum was found to be high at the regional scale but locally homogeneous. This natural distribution of diversity means that using local genotypes in biocontrol programs would effectively prevent the introduction of novel genes or genotypes. While a biocontrol program using local strains of C. purpureum would be environmentally neutral, pruned birches that are close to the treatment site would have a high susceptibility to infect by the fungus during the early spring.

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This dissertation considers the problem of trust in the context of food consumption. The research perspectives refer to institutional conditions for consumer trust, personal practices of food consumption, and strategies consumers employ for controlling the safety of their food. The main concern of the study is to investigate consumer trust as an adequate response to food risks, i.e. a strategy helping the consumer to make safe choices in an uncertain food situation. "Risky" perspective serves as a frame of reference for understanding and explaining trust relations. The original aim of the study was to reveal the meanings applied to the concepts of trust, safety and risks in the perspective of market choices, the assessments of food risks and the ways of handling them. Supplementary research tasks presumed descriptions of institutional conditions for consumer trust, including descriptions of the food market, and the presentation of food consumption patterns in St. Petersburg. The main empirical material is based on qualitative interviews with consumers and interviews and group discussions with professional experts (market actors, representatives of inspection bodies and consumer organizations). Secondary material is used for describing institutional conditions for consumer trust and the market situation. The results suggest that the idea of consumer trust is associated with the reputation of suppliers, stable quality and taste of their products, and reliable food information. Being a subjectively constructed state connected to the act of acceptance, consumer trust results in positive buying decisions and stable preferences in the food market. The consumers' strategies that aim at safe food choices refer to repetitive interactions with reliable market actors that free them from constant consideration in the marketplace. Trust in food is highly mediated by trust in institutions involved in the food system. The analysis reveals a clear pattern of disbelief in the efficiency of institutional food control. The study analyses this as a reflection of "total distrust" that appears to be a dominant mood in many contexts of modern Russia. However, the interviewees emphasize the state's decisive role in suppressing risks in the food market. Also, the findings are discussed with reference to the consumers' possibilities of personal control over food risks. Three main responses to a risky food situation are identified: the reflexive approach, the traditional approach, and the fatalistic approach.

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Yhteenveto: Kemikaalien teollisesta käsittelystä vesieliöille aiheutuvien riskien arviointi mallin avulla.

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Background and context Since the economic reforms of 1978, China has been acclaimed as a remarkable economy, achieving 9% annual growth per head for more than 25 years. However, China's health sector has not fared well. The population health gains slowed down and health disparities increased. In the field of health and health care, significant progress in maternal care has been achieved. However, there still remain important disparities between the urban and rural areas and among the rural areas in terms of economic development. The excess female infant deaths and the rapidly increasing sex ratio at birth in the last decade aroused serious concerns among policy makers and scholars. Decentralization of the government administration and health sector reform impacts maternal care. Many studies using census data have been conducted to explore the determinants of a high sex ratio at birth, but no agreement has been so far reached on the possible contributing factors. No study using family planning system data has been conducted to explore perinatal mortality and sex ratio at birth and only few studies have examined the impact of the decentralization of government and health sector reforms on the provision and organization of maternal care in rural China. Objectives The general objective of this study was to investigate the state of perinatal health and maternal care and their determinants in rural China under the historic context of major socioeconomic reforms and the one child family planning policy. The specific objectives of the study included: 1) to study pregnancy outcomes and perinatal health and their correlates in a rural Chinese county; 2) to examine the issue of sex ratio at birth and its determinants in a rural Chinese county; 3) to explore the patterns of provision, utilization, and content of maternal care in a rural Chinese county; 4) to investigate the changes in the use of maternal care in China from 1991 to 2003. Materials and Methods This study is based on a project for evaluating the prenatal care programme in Dingyuan county in 1999-2003, Anhui province, China and a nationwide household health survey to describe the changes in maternal care utilization. The approaches used included a retrospective cohort study, cross sectional interview surveys, informant interviews, observations and the use of statistical data. The data sources included the following: 1) A cohort of pregnant women followed from pregnancy up to 7 days after birth in 20 townships in the study county, collecting information on pregnancy outcomes using family planning records; 2) A questionnaire interview survey given to women who gave birth between 2001 and 2003; 3) Various statistical and informant surveys data collected from the study county; 4) Three national household health interview survey data sets (1993-2003) were utilized, and reanalyzed to described the changes in maternity care utilization. Relative risks (RR) and their confidence intervals (CI) were calculated for comparison between parity, approval status, infant sex and township groups. The chi-square test was used to analyse the disparity of use of maternal care between and within urban and rural areas and its trend across the years in China. Logistic regression was used to analyse the factors associated with hospital delivery in rural areas. Results There were 3697 pregnancies in the study cohort, resulting in 3092 live births in a total population of 299463 in the 20 study townships during 1999-2000. The average age at pregnancy in the cohort was 25.9 years. Of the women, 61% were childless, 38% already had one child and 0.3% had two children before the current pregnancy. About 90% of approved pregnancies ended in a live birth while 73% of the unapproved ones were aborted. The perinatal mortality rate was 69 per thousand births. If the 30 induced abortions in which the gestational age was more than 28 weeks had been counted as perinatal deaths, the perinatal mortality rate would have been as high as 78 per thousand. The perinatal mortality rate was negatively associated with the wealth of the township. Approximately two thirds of the perinatal deaths occurred in the early neonatal period. Both the still birth rate and the early neonatal death rate increased with parity. The risk of a stillbirth in a second pregnancy was almost four times that for a first pregnancy, while the risk of early neonatal deaths doubled. The early neonatal mortality rate was twice as high for female as for male infants. The sex difference in the early neonatal mortality rate was mainly attributable to mortality in second births. The male early neonatal mortality rate was not affected by parity, while the female early neonatal mortality rate increased dramatically with parity: it was about six times higher for second births than for first births. About 82% early neonatal deaths happened within 24 hours after birth, and during that time, girls were almost three times more likely to die than boys. The death rate of females on the day of birth increased much more sharply with parity than that of males. The total sex ratio at birth of 3697 registered pregnancies was 152 males to 100 females, with 118 and 287 in first and second pregnancies, respectively. Among unapproved pregnancies, there were almost 5 live-born boys for each girl. Most prenatal and delivery care was to be taken care of in township hospitals. At the village level, there were small private clinics. There was no limitation period for the provision of prenatal and postnatal care by private practitioners. They were not permitted to provide delivery care by the county health bureau, but as some 12% of all births occurred either at home or at private clinics; some village health workers might have been involved. The county level hospitals served as the referral centers for the township hospitals in the county. However, there was no formal regulation or guideline on how the referral system should work. Whether or not a woman was referred to a higher level hospital depended on the individual midwife's professional judgment and on the clients' compliance. The county health bureau had little power over township hospitals, because township hospitals had in the decentralization process become directly accountable to the township government. In the township and county hospitals only 10-20% of the recurrent costs were funded by local government (the township hospital was funded by the township government and the county hospital was funded by the county government) and the hospitals collected user fees to balance their budgets. Also the staff salaries depended on fee incomes by the hospital. The hospitals could define the user charges themselves. Prenatal care consultations were however free in most township hospitals. None of the midwives made postnatal home visits, because of low profit of these services. The three national household health survey data showed that the proportion of women receiving their first prenatal visit within 12 weeks increased greatly from the early to middle 1990s in all areas except for large cities. The increase was much larger in the rural areas, reducing the urban-rural difference from more than 4 times to about 1.4 times. The proportion of women that received antenatal care visits meeting the Ministry of Health s standard (at least 5 times) in the rural areas increased sharply from 12% in 1991-1993 to 36% in 2001-2003. In rural areas, the proportion increase was much faster in less developed areas than in developed areas. The hospital delivery rate increased slightly from 90% to 94% in urban areas while the proportion increased from 27% to 69% in rural areas. The fastest change was found to be in type 4 rural areas, where the utilization even quadrupled. The overall difference between rural and urban areas was substantially narrowed over the period. Multiple logistic regression analysis shows that time periods, residency in rural or urban areas, income levels, age group, education levels, delivery history, occupation, health insurance and distance from the nearest health care facilities were significantly associated with hospital delivery rates. Conclusions 1. Perinatal mortality in this study was much higher than that for urban areas as well as any reported rate from specific studies in rural areas of China. Previous studies in which calculations of infant mortality were not based on epidemiological surveys have been shown to underestimate the rates by more than 50%. 2. Routine statistics collected by the Chinese family planning system proved to be a reliable data source for studying perinatal health, including still births, neonatal deaths, sex ratio at birth and among newborns. National Household Health Survey data proved to be a useful and reliable data source for studying population health and health services. Prior to this research there were few studies in these areas available to international audiences. 3.Though perinatal mortality rate was negatively associated with the level of township economic development, the excess female early neonatal mortality rate contributed much more to high perinatal mortality rate than economic factors. This was likely a result of the role of the family planning policy and the traditional preferences for sons, which leads to lethal neglect of female newborns and high perinatal mortality. 4. The selective abortions of female foetuses were likely to contribute most to the high sex ratio at birth. The underreporting of female births seemed to have played a secondary role. The higher early neonatal mortality rate in second-born as compared to first-born children, particularly in females, may indicate that neglect or poorer care of female newborn infants also contributes to the high sex ratio at birth or among newborns. Existing family planning policy proved not to effectively control the steadily increased birth sex ratio. 5. The rural-urban gap in service utilization was on average significantly narrowed in terms of maternal healthcare in China from 1991 to 2003. This demonstrates that significant achievements in reducing inequities can be made through a combination of socio-economic development and targeted investments in improving health services, including infrastructure, staff capacities, and subsidies to reduce the costs of service utilization for the poorest. However, the huge gap which persisted among cities of different size and within different types of rural areas indicated the need for further efforts to support the poorest areas. 6. Hospital delivery care in the study county was better accepted by women because most of women think delivery care was very important while prenatal and postnatal care were not. Hospital delivery care was more systematically provided and promoted than prenatal and postnatal care by township hospital in the study area. The reliance of hospital staff income on user fees gave the hospitals an incentive to put more emphasis on revenue generating activities such as delivery care instead of prenatal and postnatal care, since delivery care generated much profits than prenatal and postnatal care . Recommendations 1. It is essential for the central government to re-assess and modify existing family planning policies. In order to keep national sex balance, the existing practice of one couple one child in urban areas and at-least-one-son a couple in rural areas should be gradually changed to a two-children-a-couple policy throughout the country. The government should establish a favourable social security policy for couples, especially for rural couples who have only daughters, with particular emphasis on their pension and medical care insurance, combined with an educational campaign for equal rights for boys and girls in society. 2. There is currently no routine vital-statistics registration system in rural China. Using the findings of this study, the central government could set up a routine vital-statistics registration system using family planning routine work records, which could be used by policy makers and researchers. 3. It is possible for the central and provincial government to invest more in the less developed and poor rural areas to increase the access of pregnant women in these areas to maternal care services. Central government together with local government should gradually provide free maternal care including prenatal and postnatal as well as delivery care to the women in poor and less developed rural areas. 4. Future research could be done to explore if county and the township level health care sector and the family planning system could be merged to increase the effectiveness and efficiency of maternal and child care. 5. Future research could be done to explore the relative contribution of maternal care, economic development and family planning policy on perinatal and child health using prospective cohort studies and community based randomized trials. Key words: perinatal health, perinatal mortality, stillbirth, neonatal death, sex selective abortion, sex ratio at birth, family planning, son preference, maternal care, prenatal care, postnatal care, equity, China

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Since the 1970s alcohol and drug use by pregnant women has become a target of political, professional and personal concern. The present study focuses on prenatal substance use and the regulation of risks by examining different kinds of societal responses to prenatal alcohol and drug use. The study analyses face-to-face encounters between professionals and service users at a specialised maternity clinic for pregnant women with substance abuse problems, medical and political discourses on the compulsory treatment of pregnant women as a means of FAS prevention and official recommendations on alcohol intake during pregnancy. Moreover, the study addresses the women s perspective by asking how women who have used illicit drugs during pregnancy perceive and rank the dangers linked to drug use. The study consists of five empirical sub-studies and a summary article. Sub-study I was written in collaboration with Dorte Hecksher and Sub-study IV with Riikka Perälä. Theoretically the study builds on the one hand, on the socio-cultural approach to the selection and perception of risks and on the other on governmentality studies which focus on the use of power in contemporary Western societies. The study is based on an ethnographic approach and makes use of the principles of multi-sited ethnography. The empirical sub-studies are based on three different types of qualitative data: ethnographic field notes from a maternity clinic from a period of 7 months, documentary material (medical journals, political documents, health education materials, government reports) and 3) interviews from maternity clinics with clients and members of staff. The study demonstrates that the logic of the regulation of prenatal alcohol use in Finland is characterised by the rise of the foetus , a process in which the urgency of protecting the foetus has gradually gained a more prominent role in the discourses on alcohol-related foetal damage. An increasing unwillingness to accept any kinds of risks when foetal health is at stake is manifested in the public debate on the compulsory treatment of pregnant women with alcohol problems and in the health authorities decision to advise pregnant women to refrain from alcohol use during pregnancy (Sub-studies I and II). Secondly, the study suggests that maternity care professionals have an ambivalent role in their mundane encounters with their pregnant clients: on the one hand professionals focus on the well-being of the foetus, but on the other, they need to take into account the women s needs and agency. The professionals daily encounters with their clients are thus characterised by hybridisation: the simultaneous use of technologies of domination and technologies of agency (Sub-studies III and IV). Finally, the study draws attention to the women s understanding of the risks of illicit drug during pregnancy, and shows that the women s understanding of risk differs from the bio-medical view. The study suggests that when drug-using pregnant women seek professional help they can feel that their moral worth is threatened by professionals negative attitudes which can make service-use challenging.