41 resultados para Maternal feeding practices
Resumo:
The biodiversity of farmland ecosystems has decreased remarkably during the latter half of the 20th century, and this development is due to intensive farming with its various environmental effects. In the countries of the EU the Common Agricultural Policy (CAP) is the main determinant affecting farmland biodiversity, since the agricultural policy defines guidelines of agricultural practices. In addition to policies promoting intensive farming, CAP also includes national agri-environment schemes (AES), in which a part of subsidies paid to farmers is directed to acts that are presumed to promote environmental protection and biodiversity. In order to shape AES into relevant and powerful tools for biodiversity protection, detailed studies on the effects of agriculture on species and species assemblages are needed. In my thesis I investigated the importance of habitat heterogeneity and effects of different habitat and landscape characteristics on farmland bird abundance and diversity in typical cereal cultivation-dominated southern Finnish agricultural environments. The extensive data used were collected by territory mapping. My two main study species were the drastically declined ortolan bunting (Emberiza hortulana) and the phenomenally increased tree sparrow (Passer montanus); in addition I studied assemblages of 20 species breeding in open arable and edge/bush habitats. In light of my results I discuss whether the Finnish AES take into account the habitat needs of farmland birds, and I provide suggestions for improvement of the future AES. My results show that heterogeneity of both uncultivated and cultivated habitats increases abundance and species richness among farmland birds, but in this respect the amount and diversity of uncultivated habitats are essential. Ditches in particular are a keystone structure for farmland birds in boreal landscapes. Ditches lined by trees or bushes increased ortolan bunting abundance. Loss of that kind of ditches (and clearance of forest and bush patches), reduced breeding ortolan buntings, mainly by decreasing availability of song-posts that are important for the breeding groups of the species. Heterogeneity of uncultivated habitats, most importantly open ditches and the habitat patch richness, increased densities and species richnesses of species assemblages of open arable and edge/bush habitats. Human impact (winter-feeding, nest-boxes) affected favourably the tree sparrow s rapid range expansion in southern Finland, but any habitat types had no significant effects. At the moment the Finnish agri-environmental policy does not conserve farmland ditches as a habitat type. Instead, sub-surface drainage is financially promoted. This is a fatal mistake as far as farmland biodiversity is concerned. In addition to the maintenance of ditches, at least the following aspects should be included more than is done previously in the measures of the future AES: 1) promotion of diverse crop rotation (especially by promoting animal husbandry), 2) maintenance of tree and bush vegetation in islets and along ditches, 3) promotion of organic farming.
Resumo:
Life-history theory states that although natural selection would favour a maximisation of both reproductive output and life-span, such a combination can not be achieved in any living organism. According to life-history theory the reason for the fact that not all traits can be maximised simultaneously is that different traits compete with each other for resources. These relationships between traits that constrain the simultaneous evolution of two or more traits are called trade-offs. Therefore, during different life-stages an individual needs to optimise its allocation of resources to life-history components such as growth, reproduction and survival. Resource limitation acts on these traits and therefore investment in one trait, e.g. reproduction, reduces the resources available for investment in another trait, e.g. residual reproduction or survival. In this thesis I study how food resources during different stages of the breeding event affect reproductive decisions in the Ural owl (Strix uralensis) and the consequences of these decisions on parents and offspring. The Ural owl is a suitable study species for such studies in natural populations since they are long-lived, site-tenacious, and feed on voles. The vole populations in Fennoscandia fluctuate in three- to four-year cycles, which create a variable food environment for the Ural owls to cope with. The thesis gives new insight in reproductive costs and their consequences in natural animal populations with emphasis on underlying physiological mechanisms. I found that supplementary fed Ural owl parents invest supplemented food resources during breeding in own self-maintenance instead of allocating those resources to offspring growth. This investment in own maintenance instead of improving current reproduction had carry-over effects to the following year in terms of increased reproductive output. Therefore, I found evidence that reduced reproductive costs improves future reproductive performance. Furthermore, I found evidence for the underlying mechanism behind this carry-over effect of supplementary food on fecundity. The supplementary-fed parents reduced their feeding investment in the offspring compared to controls, which enabled the fed female parents to invest the surplus resources in parasite resistance. Fed female parents had lower blood parasite loads than control females and this effect lasted until the following year when also reproductive output was increased. Hence, increased investment in parasite resistance when resources are plentiful has the potential to mediate positive carry-over effects on future reproduction. I further found that this carry-over effect was only present when potentials for future reproduction were good. The thesis also provides new knowledge on resource limitation on maternal effects. I found that increased resources prior to egg laying improve the condition and health of Ural owl females and enable them to allocate more resources to reproduction than control females. These additional resources are not allocated to increase the number of offspring, but instead to improve the quality of each offspring. Fed Ural owl females increased the size of their eggs and allocated more health improving immunological components into the eggs. Furthermore, the increased egg size had long-lasting effects on offspring growth, as offspring from larger eggs were heavier at fledging. Limiting resources can have different short- and long-term consequences on reproductive decisions that affect both offspring number and quality. In long-lived organisms, such as the Ural owl, it appears to be beneficial in terms of fitness to invest in long breeding life-span instead of additional investment in current reproduction. In Ural owls, females can influence the phenotypic quality of the offspring by transferring additional resources to the eggs that can have long-lasting effects on growth.
Resumo:
In aquatic systems, the ability of both the predator and prey to detect each other may be impaired by turbidity. This could lead to significant changes in the trophic interactions in the food web of lakes. Most fish use their vision for predation and the location of prey can be highly influenced by light level and clarity of the water environment. Turbidity is an optical property of water that causes light to be scattered and absorbed by particles and molecules. Turbidity is highly variable in lakes, due to seasonal changes in suspended sediments, algal blooms and wind-driven suspension of sediments especially in shallow waters. There is evidence that human activity has increased erosion leading to increased turbidity in aquatic systems. Turbidity could also play a significant role in distribution of fish. Turbidity could act as a cover for small fish and reduce predation risk. Diel horizontal migration by fish is common in shallow lakes and is considered as consequences of either optimal foraging behaviour for food or as a trade-off between foraging and predator avoidance. In turbid lakes, diel horizontal migration patterns could differ since turbidity can act as a refuge itself and affect the predator-prey interactions. Laboratory experiments were conducted with perch (Perca fluviatilis L.) and white bream (Abramis björkna (L.)) to clarify the effects of turbidity on their feeding. Additionally to clarify the effects of turbidity on predator preying on different types of prey, pikeperch larvae (Sander lucioperca (L.)), Daphnia pulex (Leydig), Sida crystallina (O.F. Müller), and Chaoborus flavicans (Meigen) were used as prey in different experiments. To clarify the role of turbidity in distribution and diel horizontal migration of perch, roach (Rutilus rutilus (L.)) and white bream, field studies were conducted in shallow turbid lakes. A clear and a turbid shallow lake were compared to investigate distribution of perch and roach in these two lakes in a 15-year study period. Feeding efficiency of perch and white bream was not significantly affected with increasing clay turbidity up to 50 NTU. The perch experiments with pikeperch larvae suggested that clay turbidity could act as a refuge especially at turbidity levels higher than 50 NTU. Perch experiments with different prey types suggested that pikeperch larvae probably use turbidity as a refuge better compared to Daphnia. Increase in turbidity probably has stronger affect on perch predating on plant-attached prey. The main findings of the thesis show that turbidity can play a significant role in distribution of fish. Perch and roach could use turbidity as refuge when macrophytes disappear while small perch may also use high turbidity as refuge when macrophytes are present. Floating-leaved macrophytes are probably good refuges for small fish in clay-turbid lakes and provide a certain level of turbidity and not too complex structure for refuge. The results give light to the predator-prey interactions in turbid environments. Turbidity of water should be taken in to account when studying the diel horizontal migrations and distribution of fish in shallow lakes.
Resumo:
Background: Both maternal and fetal complications are increased in diabetic pregnancies. Although hypertensive complications are increased in pregnant women with pregestational diabetes, reports on hypertensive complications in women with gestational diabetes mellitus (GDM) have been contradictory. Congenital malformations and macrosomia are the main fetal complications in Type 1 diabetic pregnancies, whereas fetal macrosomia and birth trauma but not congenital malformations are increased in GDM pregnancies. Aims: To study the frequency of hypertensive disorders in gestational diabetes mellitus. To evaluate the risk of macrosomia and brachial plexus injury (Erb’s palsy) and the ability of the 2-hour glucose tolerance test (OGTT) combined with the 24-hour glucose profile to distinguish between low and high risks of fetal macrosomia among women with GDM. To evaluate the relationship between glycemic control and the risk of fetal malformations in pregnancies complicated by Type 1 diabetes mellitus. To assess the effect of glycemic control on the occurrence of preeclampsia and pregnancy-induced hypertension in Type 1 diabetic pregnancies. Subjects: A total of 986 women with GDM and 203 women with borderline glucose intolerance (one abnormal value in the OGTT) with a singleton pregancy, 488 pregnant women with Type 1 diabetes (691 pregnancies and 709 offspring), and 1154 pregnant non-diabetic women (1181 pregnancies and 1187 offspring) were investigated. Results: In a prospective study on 81 GDM patients the combined frequency of preeclampsia and PIH was higher than in 327 non-diabetic controls (19.8% vs 6.1%, p<0.001). On the other hand, in 203 women with only one abnormal value in the OGTT, the rate of hypertensive complications did not differ from that of the controls. Both GDM women and those with only one abnormal value in the OGTT had higher pre-pregnancy weights and BMIs than the controls. In a retrospective study involving 385 insulin-treated and 520 diet-treated GDM patients, and 805 non-diabetic control pregnant women, fetal macrosomia occurred more often in the insulin-treated GDM pregnancies (18.2%, p<0.001) than in the diet-treated GDM pregnancies (4.4%), or the control pregnancies (2.2%). The rate of Erb’s palsy in vaginally delivered infants was 2.7% in the insulin-treated group of women and 2.4% in the diet-treated women compared with 0.3% in the controls (p<0.001). The cesarean section rate was more than twice as high (42.3% vs 18.6%) in the insulin-treated GDM patients as in the controls. A major fetal malformation was observed in 30 (4.2%) of the 709 newborn infants in Type 1 diabetic pregnancies and in 10 (1.4%) of the 735 controls (RR 3.1, 95% CI 1.6–6.2). Even women whose levels of HbA1c (normal values less than 5.6%) were only slightly increased in early pregnancy (between 5.6 and 6.8%) had a relative risk of fetal malformation of 3.0 (95% CI 1.2–7.5). Only diabetic patients with a normal HbA1c level (<5.6%) in early pregnancy had the same low risk of fetal malformations as the controls. Preeclampsia was diagnosed in 12.8% and PIH in 11.4% of the 616 Type 1 diabetic women without diabetic nephropathy. The corresponding frequencies among the 854 control women were 2.7% (OR 5.2; 95% CI 3.3–8.4) for preeclampsia and 5.6% (OR 2.2, 95% CI 1.5–3.1) for PIH. Multiple logistic regression analysis indicated that glycemic control, nulliparity, diabetic retinopathy and duration of diabetes were statistically significant independent predictors of preeclampsia. The adjusted odds ratios for preeclampsia were 1.6 (95% CI 1.3–2.0) for each 1%-unit increment in the HbA1c value during the first trimester and 0.6 (95% CI 0.5–0.8) for each 1%-unit decrement during the first half of pregnancy. In contrast, changes in glycemic control during the second half of pregnancy did not alter the risk of preeclampsia. Conclusions: In type 1 diabetic pregnancies it is extremely important to achieve optimal glycemic control before pregnancy and maintain it throughout pregnancy in order to decrease the complication rates both in the mother and in her offspring. The rate of fetal macrosomia and birth trauma in GDM pregnancies, especially in the group of insulin-treated women, is still relatively high. New strategies for screening, diagnosing, and treatment of GDM must be developed in order to decrease fetal and neonatal complications.
Resumo:
My doctoral dissertation in sociology and Russian studies, Social Networks and Everyday Practices in Russia, employs a "micro" or "grassroots" perspective on the transition. The study is a collection of articles detailing social networks in five different contexts. The first article examines Russian birthdays from a network perspective. The second takes a look at health care to see whether networks have become obsolete in a sector that is still overwhelmingly public, but increasingly being monetarised. The third article investigates neighbourhood relations. The fourth details relationships at work, particularly from the vantage point of internal migration. The fifth explores housing and the role of networks and money both in the Soviet and post-Soviet era. The study is based on qualitative social network and interview data gathered among three groups, teachers, doctors and factory workers, in St. Petersburg during 1993-2000. Methodologically it builds on a qualitative social network approach. The study adds a critical element to the discussion on networks in post-socialism. A considerable consensus exists that social networks were vital in state socialist societies and were used to bypass various difficulties caused by endemic shortages and bureaucratic rigidities, but a more debated issue has been their role in post-socialism. Some scholars have argued that the importance of networks has been dramatically reduced in the new market economy, whereas others have stressed their continuing importance. If a common denominator in both has been a focus on networks in relation to the past, a more overlooked aspect has been the question of inequality. To what extent is access to networks unequally distributed? What are the limits and consequences of networks, for those who have access, those outside networks or society at large? My study provides some evidence about inequalities. It shows that some groups are privileged over others, for instance, middle-class people in informal access to health care. Moreover, analysing the formation of networks sheds additional light on inequalities, as it highlights the importance of migration as a mechanism of inequality, for example. The five articles focus on how networks are actually used in everyday life. The article on health care, for instance, shows that personal connections are still important and popular in post-Soviet Russia, despite the growing importance of money and the emergence of "fee for service" medicine. Fifteen of twenty teachers were involved in informal medical exchange during a two-week study period, so that they used their networks to bypass the formal market mechanisms or official procedures. Medicines were obtained through personal connections because some were unavailable at local pharmacies or because these connections could provide medicines for a cheaper price or even for free. The article on neighbours shows that "mutual help" was the central feature of neighbouring, so that the exchange of goods, services and information covered almost half the contacts with neighbours reported. Neighbours did not provide merely small-scale help but were often exchange partners because they possessed important professional qualities, had access to workplace resources, or knew somebody useful. The article on the Russian work collective details workplace-related relationships in a tractor factory and shows that interaction with and assistance from one's co-workers remains important. The most interesting finding was that co-workers were even more important to those who had migrated to the city than to those who were born there, which is explained by the specifics of Soviet migration. As a result, the workplace heavily influenced or absorbed contexts for the worker migrants to establish relationships whereas many meeting-places commonly available in Western countries were largely absent or at least did not function as trusted public meeting places to initiate relationships. More results are to be found from my dissertation: Anna-Maria Salmi: Social Networks and Everyday Practices in Russia, Kikimora Publications, 2006, see www.kikimora-publications.com.
Resumo:
The use of human tissue sample collections has become an important tool in biomedical research. The collection, use and distribution of human tissue samples, which include blood and diagnostic tissue samples, from which DNA can be extracted and analyzed has also become a major bio-political preoccupation, not only in national contexts, but also at the transnational level. The foundation of medical research rests on the relationship between the doctor and the research subject. This relationship is a social one, in that it is based on informed consent, privacy and autonomy, where research subjects are made aware of what they are getting involved in and are then able to make an informed decision as to whether or not to participate. Within the post-genomic era, however, our understanding of what constitutes informed consent, privacy and autonomy is changing in relation to the needs of researchers, but also as a reflection of policy aspirations. This reflects a change in the power relations between the rights of the individual in relation to the interests of science and society. Using the notions of tissue economies and biovalue (Waldby, 2002) this research explores the changing relationship between sources and users of samples in biomedical research by examining the contexts under which human tissue samples and the information that is extracted from them are acquired, circulated and exchanged in Finland. The research examines how individual rights, particularly informed consent, are being configured in relation to the production of scientific knowledge in tissue economies in Finland from the 1990s to the present. The research examines the production of biovalue through the organization of scientific knowledge production by examining the policy context of knowledge production as well as three case studies (Tampere Research Tissue Bank, Hereditary Non-polyposis Colorectal Cancer and the Finnish Genome Information Center) in which tissues are acquired, circulated and exchanged in Finland. The research shows how interpretations of informed consent have become divergent and the elements and processes that have contributed to these differences. This inquiry shows how the relationship between the interests of individuals is re-configured in relation to the interests of science and society. It indicates how the boundary between interpretations of informed consent, on the one hand, and social and scientific interests, on the other, are being re-drawn and that this process is underscored, in part, by the economic, commercial and preventive potential that research using tissue samples are believed to produce. This can be said to fundamentally challenge the western notion that the rights of the individual are absolute and inalienable within biomedical legislation.
Resumo:
Whilst previous research on Human Resource Management (HRM) in subsidiaries of multinational companies (MNCs) has focused extensively on the HRM practices that exist in foreign subsidiaries and the extent to which they resemble MNC home country and/or local host country practices, considerably less attention has been directed at the question of how these practices come to exist. Accordingly, this thesis aims to shed light on the processes that shape HRM practices and capabilities in MNC subsidiaries. The main contribution of the thesis is the focus on how; how HRM practices are integrated in MNC subsidiaries, and how subsidiary HRM capabilities are developed through involvement in social networks. Furthermore, this thesis includes a time aspect which, despite not being purely longitudinal, provides an indication of the ongoing changes in HRM in MNC subsidiaries in China. Data for this study were collected in 2005-2006 through structured face to face interviews with 153 general managers and HR managers in 87 subsidiaries of European MNCs located in China. Five of the six thesis papers build on this questionnaire data and one paper builds on qualitative data collected at the same time. Two papers build on dual data sets, meaning that they in addition to the abovementioned data include quantitative questionnaire data from 1996 and 1999 respectively. The thesis focuses on the following four sub-questions i) To what extent do subsidiary HRM practices resemble parent MNC and host country practices? How has this changed over time and why? ii) How are HRM practices integrated into MNC subsidiaries and why are certain integration mechanisms used? iii) How does involvement in internal and external social networks influence subsidiary HRM capabilities? iv) What factors influence the strategic role of the subsidiary HR department? Regarding the first sub-question the findings indicate that the HRM practices of MNC subsidiaries in China are converging with both local company practices and parent MNC practices. This is interesting in the sense that it suggests that the isomorphic pressures the subsidiary faces from the MNC and from its local host environment are not always in conflict with each other. Concerning the question of how HRM practices are integrated into MNC subsidiaries and why certain integration mechanisms are used, the thesis provides a fine-grained examination of four mechanisms that MNCs use to integrate HRM practices in subsidiaries. The findings suggest that MNCs use a variety of different integration mechanisms as complements rather than as substitutes for each other. Furthermore, it is apparent that different contextual factors in the subsidiary and the subsidiary-headquarters relationship influence why certain mechanisms are or are not used. The most interesting contribution of the thesis in regard to the third question is that it highlights the importance of network involvement for learning about HRM practices in the Chinese context. Networks with other MNCs in China clearly emerged as particularly important contributors to enhanced HRM capabilities. Finally, concerning the fourth sub-question the findings indicate that the role of the HR department in MNC subsidiaries in China had become more strategic between 1999 and 2006.
Resumo:
Mainstream research on management generally continues to ignore gender relations. Even so, over recent years there has been a major growth of international research on gender relations in organizations. Yet, most of this has focused on gender relations in lower or middle levels rather than at the apex of the organization. This book draws on research on gender policies, structures and practices of management in large Finnish corporations. It builds on earlier survey work of gender policies in the 100 largest corporations in Finland, to examine, through qualitative interviews, more detailed gendered processes in seven selected corporations. These represent corporations that are ‘relatively active’, ‘moderately active’, and ‘not active’ in relation to gender equality. Key issues include contrasts between formal policies and organizational practices; different corporate contexts and individual managers’ views; definition and scope of gender policy; and the relation of gender policies and diversity policy. This focus on gender policies is understood and located within organizational structures, most obviously gendered corporate hierarchies. Important structures include national context in relation to transnationalization, relations of headquarters and subsidiaries, and interrelations of management, policy development and policy implementation. Gender relations in practice and gender practices are considered in more detail. These women and men managers operate at the intersections of gendered transnational managerial work, careers and family-type relations, including marriage and children, or lack thereof. Women and men managers may be part of the same management levels or management teams, but have totally different family-type situations and gendered experiences. Interconnections of management, domestic life and transnationalizations are intensely gendered matters. The debate on the public/private continues to be important for both gender relations and organizational relations, but complicated through transnationalizations. The modern transnational corporation is considered in terms of gender divisions and gender power, with particular reference to top management. The concluding discussion notes implications for research and policy.