890 resultados para Decline in fertility
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Party identification traditionally is seen as an important linkage mechanism, connecting voters to the party system. Previous analyses have suggested that the level of party identity is in decline in Germany, and in this article, we first expand previous observations with more recent data. These suggest that the erosion of party identity continues up to the present time. An age-period-cohort analysis of the panel data of the SOEP panel suggests that period effects are significantly negative. Furthermore, it can be observed that throughout the 1992-2009 observation period, education level and political interest have become more important determinants of party identity. Contrary to some of the literature, therefore, it can be shown that the loss of party identity is concentrated among groups with lower levels of political sophistication, indicating that the socio-economic profile of the group with a sense of party identification has become more distinct compared to the population as a whole. In the discussion, we investigate the theoretical and democratic consequences of this trend.
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Frozen-thawed boar sperm holds the potential to have an impact on the future of the swine industry. Utilization of this technology could improve a swine producer’s ability to access top-tier genetics from around the world, to improve efficiency, profitability, and the quality of product to meet consumer demands. Effective application of frozen-thawed sperm can help reduce the potential risk associated with devastating economic loss due to the spread of disease. Frozen storage of boar sperm also provides a safeguard in the event of disease outbreaks, as genetic material from paternal lines can be preserved and banked for repopulation purposes. Historically these benefits have been masked by reduction in fertility measures such as litter size. The reduced fertility results from the damage sustained by the sperm cell during cryopreservation. However, increased understanding of this damage has lead to improved cryopreservation methods, ultimately increasing post-thaw viability and fertility. Enhancements in breeding technology have also resulted in a better understanding of the AI methods required to achieve acceptable farrowing rates and litter size. Fertility following AI with frozen-thawed sperm is approaching that of liquid stored sperm, and producers may soon reap the benefits of this technology. This thesis will outline the current swine industry, opportunities for utilizing frozen-thawed sperm, the main components of sperm, why they are susceptible to damage, and current freezing and breeding practices. Objective 1 was to develop a cryopreservation protocol for our lab that resulted in consistent post-thaw motility ( ≥ 40%) that would eventually be used by Illinois boar studs for domestic and international sale of frozen sperm. Evaluation with both manual microscopy and CASA methods were conducted to verify quality. A preliminary breeding trial was then conducted to test the fertility of sperm frozen with this method. There were 41 ejaculates from 23 boars used for freezing. Sperm were frozen at 1.4x109 sperm/mL, averaging 55.61.1% (meanSE) motility, following thaw. The samples assessed were not different (P>0.05) in motility when compared with manual or CASA systems, and results were most reliable at a 1:40 sperm dilution. In the preliminary breeding trial, gilts (n=14) were inseminated with either a single (n=10) or double (n=4) AI using 1, 2, or 4x109 motile, frozen-thawed sperm. Overall, the resulting pregnancy rates averaged 71.4% and numbers of normal fetuses per litter averaged 15.51.3 per litter. A feasibility study for freezing cost per ejaculate was estimated at $275/ejaculate or $11/dose of frozen-thawed semen at standard doses of 5x109 total frozen-thawed sperm. This cost estimate did not include genetic value, fixed equipment costs, depreciation, or variable lab space fees. Objective 2 focused on the proper methods for breeding with frozen-thawed boar sperm to achieve fertility. Our hypothesis was that increased numbers of inseminations and increased numbers of motile frozen-thawed sperm would improve pregnancy rate and litter size. Results showed acceptable fertility at high sperm numbers, but also the optimal method for insemination with the lowest dose tested. Gilts (n=111) responded to synchronization methods and were bred with 1, 2, or 4x109 motile frozen-thawed sperm from six boars using a single AI at 32 h, or a double AI, with the first AI at 24 and 32 h following estrus. Ultrasound was conducted at 12 h intervals to estimate the time of ovulation. On day 32 of gestation, overall pregnancy rate (73%) and number of normal fetuses per litter (10.80.5) across all treatments did not differ, and were not affected by number of motile sperm, or the interaction of number of motile sperm and number of inseminations. However, the number of inseminations tended to affect (P=0.14) the number of normal fetuses. Litter size increased with a double AI compared to single AI. Multiple inseminations helped to allow insemination to occur close to ovulation in response to variation in the time of ovulation. Both pregnancy rate and number of normal fetuses were greater when the time of the AI at 32 h occurred closer to the estimated time of ovulation (P<0.05). In addition, other factors such as presence of an abnormal ovary at day 30 decreased (P<0.001) pregnancy rate, while boar affected number of normal fetuses (P<0.01). Analysis of our data using a fertility index revealed doses of 2x109 motile sperm with multiple AI can achieve acceptable fertility with use of less sperm, when compared to AI using 4x109 motile sperm. The methods described here will investigate the potential for improved fertility when using frozen-thawed sperm, while accounting for variation in time of ovulation.
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Race as a biological category has a long and troubling history as a central ordering concept in the life and human sciences. The mid-twentieth century has been marked as the point where biological concepts of race began to disappear from science. However, biological definitions of race continue to penetrate scientific understandings and uses of racial concepts. Using the theoretical frameworks of critical race theory and science and technology studies and an in-depth case study of the discipline of immunology, this dissertation explores the appearance of a mid-century decline of concepts of biological race in science. I argue that biological concepts of race did not disappear in the middle of the twentieth century but were reconfigured into genetic language. In this dissertation I offer a periodization of biological concepts of race. Focusing on continuities and the effects of contingent events, I compare how biological concepts of race articulate with racisms in each period. The discipline of immunology serves as a case study that demonstrates how biological concepts of race did not decline in the postwar era, but were translated into the language of genetics and populations. I argue that the appearance of a decline was due to events both internal and external to the science of immunology. By framing the mid-twentieth century disappearance of race in science as the triumph of an antiracist racial project of science, it allows us to more clearly see the more recent resurgence of race in science as a recycling of older themes and tactics from the racist science projects of the past.
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The survival, absolute population size, gonotrophic cycle duration, and temporal and spatial abundance of Nyssomyia neivai (Pinto) were studied in a rural area endemic for American cutaneous leishmaniasis (ACL) in Conchal, Sõo Paulo State, southeastern Brazil, using mark-release-recapture techniques and by monitoring population fluctuation. The monthly abundance exhibited a unimodal pattern, with forest and domicile habitats having the highest relative abundances. A total of 1,873 males and 3,557 females were marked and released during the six experiments, of which 4.1-13.0 per cent of males and 4.1-11.8 per cent of females were recaptured. Daily survivorship estimated from the decline in recaptures per day was 0.681 for males and 0.667 for females. Gonotrophic cycle duration was estimated to be 4.0 d. Absolute population size was calculated using the Lincoln Index and ranged from 861 to 4,612 males and from 2,187 to 19,739 females. The low proportion of females that reach the age when they are potentially infective suggests that N. neivai has a low biological capacity to serve as a vector and that factors such as high biting rates and opportunistic feeding behavior would be needed to enable Leishmania (Viannia) braziliensis Vianna transmission. This agreed with the epidemiological pattern of ACL in southeastern Brazil that is characterized by low incidence, with isolated cases acquired principally within domiciliary habitats
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Objective To assess trends in the prevalence and social distribution of child stunting in Brazil to evaluate the effect of income and basic service redistribution policies implemented in that country in the recent past. Methods The prevalence of stunting (height-for-age z score below \22122 using the Child Growth Standards of the World Health Organization) among children aged less than 5 years was estimated from data collected during national household surveys carried out in Brazil in 1974\201375 (n = 34 409), 1989 (n = 7374), 1996 (n = 4149) and 2006\201307 (n = 4414). Absolute and relative socioeconomic inequality in stunting was measured by means of the slope index and the concentration index of inequality, respectively. Findings Over a 33-year period, we documented a steady decline in the national prevalence of stunting from 37.1 per cent to 7.1 per cent. Prevalence dropped from 59.0 per cent to 11.2 per cent in the poorest quintile and from 12.1 per cent to 3.3 per cent among the wealthiest quintile. The decline was particularly steep in the last 10 years of the period (1996 to 2007), when the gaps between poor and wealthy families with children under 5 were also reduced in terms of purchasing power; access to education, health care and water and sanitation services; and reproductive health indicators.Conclusion In Brazil, socioeconomic development coupled with equity-oriented public policies have been accompanied by marked improvements in living conditions and a substantial decline in child undernutrition, as well as a reduction of the gap in nutritional status between children in the highest and lowest socioeconomic quintiles. Future studies will show whether these gains will be maintained under the current global economic crisis
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Background: It is recognized that the growing epidemic of metabolic syndrome is related to dietary and lifestyle changes. Objective: The purpose of this study was to evaluate short-term application of nutritional counseling in women with metabolic syndrome. Methods: This follow-up study was conducted from September to November 2008 with thirty three women >= 35 years old screened clinically for nutritional counseling. Dietary intake was reported, and biochemical and body composition measures were taken at baseline and after three months of follow-up. Results: Of the 33 women evaluated, 29 patients completed the study. The prevalence of type 2 diabetes mellitus, hypertension, dyslipidemia, and obesity was high at 38%, 72.4%, 55.2%, and 75.8%, respectively. At the end of three-months of follow-up, a significant decline in body mass index, waist circumference, triceps skinfold, and triglycerides was observed, as was an increase in calcium and vitamin D intake. The multiple regression analysis showed that changes in body mass index, triceps skinfold, waist circumference and triglyceride levels after nutritional intervention were positively associated with changes in anthropometric (loss of body weight) and biochemical (decrease of TG/HDL-c ratio) parameters. Moreover, waist circumference changes were negatively associated with changes in calcium and vitamin D intake. Conclusion: Short-term nutritional counseling improved some factors of metabolic syndrome. Moreover, the increases in calcium and vitamin D consumption can be associated with the improvement in markers of metabolic syndrome.
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Background: Concomitant infections may influence HIV progression by causing chronic activation leading to decline in T-cell function. In the Americas, visceral (AVL) and tegumentary leishmaniasis (ATL) have emerged as important opportunistic infections in HIV-AIDS patients and both of those diseases have been implicated as potentially important co-factors in disease progression. We investigated whether leishmaniasis increases lymphocyte activation in HIV-1 co-infected patients. This might contribute to impaired cellular immune function. Methods: To address this issue we analyzed CD4(+) T absolute counts and the proportion of CD8(+) T cells expressing CD38 in Leishmania/HIV co-infected patients that recovered after anti-leishmanial therapy. Results: We found that, despite clinical remission of leishmaniasis, AVL co-infected patients presented a more severe immunossupression as suggested by CD4(+) T cell counts under 200 cells/mm(3), differing from ATL/HIV-AIDS cases that tends to show higher lymphocytes levels (over 350 cells/mm(3)). Furthermore, five out of nine, AVL/HIV-AIDS presented low CD4(+) T cell counts in spite of low or undetectable viral load. Expression of CD38 on CD8(+) T lymphocytes was significantly higher in AVL or ATL/HIV-AIDS cases compared to HIV/AIDS patients without leishmaniasis or healthy subjects. Conclusions: Leishmania infection can increase the degree of immune system activation in individuals concomitantly infected with HIV. In addition, AVL/HIV-AIDS patients can present low CD4(+) T cell counts and higher proportion of activated T lymphocytes even when HIV viral load is suppressed under HAART. This fact can cause a misinterpretation of these laboratorial markers in co-infected patients.
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This work was undertaken to provide further insight into the role of mammalian target of rapamycin complex 1 (mTORC1) in skeletal muscle regeneration, focusing on myofiber size recovery. Rats were treated or not with rapamycin, an mTORC1 inhibitor. Soleus muscles were then subjected to cryolesion and analyzed 1, 10, and 21 days later. A decrease in soleus myofiber cross-section area on post-cryolesion days 10 and 21 was accentuated by rapamycin, which was also effective in reducing protein synthesis in these freeze-injured muscles. The incidence of proliferating satellite cells during regeneration was unaltered by rapamycin, although immunolabeling for neonatal myosin heavy chain (MHC) was weaker in cryolesion+rapamycin muscles than in cryolesion-only muscles. In addition, the decline in tetanic contraction of freeze-injured muscles was accentuated by rapamycin. This study indicates that mTORC1 plays a key role in the recovery of muscle mass and the differentiation of regenerating myofibers, independently of necrosis and satellite cell proliferation mechanisms. Muscle Nerve 42: 778-787,2010
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The purpose of the present study was to compare the effects of eight weeks of strength training on fatigue resistance in men and women. Thirty-three men and twenty-three women performed eight weeks of strength training in three weekly sessions. Subjects performed four sets using 80% of 1-RM tests on bench press, squat and arm curl. Fatigue index (FI) was used for analysis of decline in motor performance along the sets. The sum of the number of repetitions accomplished in the four sets in each exercise was used to indicate the fatigue resistance. Anova or Ancova two-way ( time x gender) was employed for statistical analysis ( P < 0.05). Eight weeks of strength training increased significantly 1-RM strength, fatigue resistance and total number of repetitions in both genders. FI decreased significantly in both genders after training ( men = 50% vs. women = Time x gender interaction was observed in the total number of repetitions in squat ( P = 0.04) and arm curl exercises, regarding gains to women ( P = 0.01). In conclusion, eight weeks of ST improved strength, FR, FI and total number of repetitions performed. However, women obtained greater adaptations than men.
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The water-wind crisscross region of the Loess Plateau in China is comprised of 17.8 million hectares of highly erodible soil under limited annual rainfall. This requires a sustainable water balance for the restoration of dryland ecosystems to reduce and manage soil erosion. In this region, alfalfa has been one of the main legumes grown to minimize soil erosion. However, alfalfa yields were significantly lower in years of reduced rainfall suggesting that high water use and deep rooting alfalfa make it an unsustainable crop due to the long-term decline in soil water storage and productivity. Our objectives in this Study were to evaluate the soil water balance of Loess Plateau soils during vegetative restoration and to evaluate practices that prevent soil desiccation and promote ecosystem restoration and sustainability. Field observations of soil moisture recovery and soil erosion were carried out for five years after alfalfa was replaced with different crops and with bare soil. Soil water content changes in cropland, rangeland, and bare soil were tracked over several years, using a water balance approach. Results indicate that growing forages significantly reduced runoff and sediment transport. A forage-food-crop rotation is a better choice than other cropping systems for achieving sustainable productivity and preventing soil erosion and desiccation. However, economic considerations have prevented its widespread adoption by local farmers. Alternatively, this study recommends consideration of grassland crops or forest ecosystems to provide a sustainable water balance in the Loess Plateau of China. (C) 2009 Elsevier B.V. All rights reserved.
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We measured CO(2) efflux from wood for Eucalyptus in Hawaii for 7 years and compared these measurements with those on three-and four-and-a-half-year-old Eucalyptus in Brazil. In Hawaii, CO(2) efflux from wood per unit biomass declined similar to 10x from age two to age five, twice as much as the decline in tree growth. The CO(2) efflux from wood in Brazil was 8-10x lower than that for comparable Hawaii trees with similar growth rates. Growth and maintenance respiration coefficients calculated from Hawaii wood CO(2) efflux declined with tree age and size (the growth coefficient declined from 0.4 mol C efflux mol C(-1) wood growth at age one to 0.1 mol C efflux mol C(-1) wood growth at age six; the maintenance coefficient from 0.006 to 0.001 mu mol C (mol C biomass)(-1) s(-1) at 20 degrees C over the same time period). These results suggest interference with CO(2) efflux through bark that decouples CO(2) efflux from respiration. We also compared the biomass fractions and wood CO(2) efflux for the aboveground woody parts for 3- and 7-year-old trees in Hawaii to estimate how focusing measurements near the ground might bias the stand-level estimates of wood CO(2) efflux. Three-year-old Eucalyptus in Hawaii had a higher proportion of branches < 0.5 cm in diameter and a lower proportion of stem biomass than did 7-year-old trees. Biomass-specific CO(2) efflux measured at 1.4 m extrapolated to the tree could bias tree level estimates by similar to 50%, assuming no refixation from bark photosynthesis. However, the bias did not differ for the two tree sizes. Foliar respiration was identical per unit nitrogen for comparable treatments in Brazil and Hawaii (4.2 mu mol C mol N(-1) s(-1) at 20 degrees C).
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The starting point of this thesis was a desire to explain the rapid demise in the popularity which the Communist Party enjoyed in Queensland during the second world war. Wartime Queensland gave the Australian Communist Party its highest state vote and six years later Queensland again gave the Communist Party its highest state vote - this time however, to ban the Party. From this I was led into exploring the changing policies, beliefs and strategies of the Party, as well as the many sub-groups on its periphery, and the shifts in public response to these. In 1939 Townsville elected Australia's first Communist alderman. Five years later, Bowen elected not only Australia's first but also the British Empire's first, Communist state government member. Of the five electorates the Australian Communist Party contested in the 1944 Queensland State elections, in none did the Party's candidate receive less than twenty per-cent of the formal vote. Not only was the Party seemingly enjoying considerable popular support but this was occurring in a State which, but for the Depression years (May 1929 - June 1932) had elected a Labor State Government at every state election since 1915. In the September 1951 Constitution Alteration Referendum, 'Powers To Deal With Communists and Communism', Queensland regist¬ered the nation's highest "Yes" majority - 55.76% of the valid vote. Only two other states registered a majority in favour of the referendum's proposals, Western Australia and Tasmania. As this research was undertaken it became evident that while various trends exhibited at the time, anti-Communism, the work of the Industrial Groups, Labor opportunism, local area feelings, ideological shifts of the Party, tactics of Communist-led unions, etc., were present throughout the entire period, they were best seen when divided into three chronological phases of the Party's history and popularity. The first period covers the consolidation of the Party's post-Depression popularity during the war years as it benefited from the Soviet Union's colossal contribution to the Allied war efforts, and this support continued for some six months or so after the war. Throughout the period Communist strength within the trade union movement greatly increased as did total Party membership. The second period was marked by a rapid series of events starting in March 1946, with Winston Churchill's "Official Opening" of the Cold War by his sweeping attack on Communism and Russia, at Fulton. Several days later the first of a series of long and bitter strikes in Communist-led unions occurred, as the Party mobil¬ized for what it believed would be a series of attacks on the working class from a ruling class, defending a capitalist system on the verge of an economic collapse. It was a period when the Party believed this ruling class was using Labor reformism as a last desperate 'carrot' to get workers to accept their lot within a capitalist economic framework. Out of the Meat Strike emerged the Industrial Groups, who waged not only a determined war against Communist trade union leadership but also encouraged the A.W.U.-influenced State Labor apparatus to even greater anti-Communist antagonisms. The Communist Party's increasing militancy and Labor's resistance to it, ended finally in the collapse of the Chifley Labor government. Characteristically the third period opens with the Communist Party making an another about-face, desperately trying to form an alliance with the Labor Party and curbing its former adventurist industrial policy, as it prepared for Menzies' direct assault. The Communist Party's activities were greatly reduced, a function of both a declining member-ship and, furthermore, a membership reluctant to confront an increasingly hostile society. In examining the changing policies, beliefs and strategies of the Party and the shifts in public response to these, I have tried to distinguish between general trends occurring within Australia and the national party, and trends peculiar to Queensland and the Queensland branch of the Party, The Communist Party suffered a decline in support and membership right across Australia throughout this period as a result of the national policies of the Party, and the changing nature of world politics. There were particular features of this decline that were peculiar to Queensland. I have, however, singled out three features of particular importance throughout the period for a short but more specifically detailed analysis, than would be possible in a purely chronological study: i.e. the Party's structure, the Party's ideological subservience to Moscow, and the general effect upon it of the Cold War.
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Eletter to Tobacco Control in response to an eletter published in the same journal about whether snus (Swedish moist oral snuff) was responsible for a decline in smoking prevalence among men in Sweden.
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Intense exercise stimulates the systemic release of a variety of factors that alter neutrophil surface receptor expression and functional activity. These alterations may influence resistance to infection after intense exercise. The aim of this study was to examine the influence of exercise intensity on neutrophil receptor expression, degranulation (measured by plasma and intracellular myeloperoxidase concentrations), and respiratory burst activity. Ten well-trained male runners ran on a treadmill for 60 min at 60% [moderate-intensity exercise (MI)] and 85% maximal oxygen consumption [high-intensity exercise (HI)]. Blood was drawn immediately before and after exercise and at 1 h postexercise. Immediately after HI, the expression of the neutrophil receptor CD16 was significantly below preexercise values (P < 0.01), whereas MI significantly reduced CD35 expression below preexercise values (P < 0.05). One hour after exercise at both intensities, there was a significant decline in CD11b expression (P < 0.05) and a further decrease in CD16 expression compared with preexercise values (P < 0.01). CD16 expression was lower 1 h after HI than 1 h after MI (P < 0.01). Immediately after HI, intracellular myeloperoxidase concentration was less than preexercise values (P < 0.01), whereas plasma myeloperoxidase concentration was greater (P < 0.01), indicating that HI stimulated neutrophil degranulation. Plasma myeloperoxidase concentration was higher immediately after HI than after MI (P < 0.01). Neutrophil respiratory burst activity increased after HI (P < 0.01). In summary, both MI and HI reduced neutrophil surface receptor expression. Although CD16 expression was reduced to a greater extent after HI, this reduction did not impair neutrophil degranulation and respiratory burst activity.
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The World Health Organization (WHO) MONICA Project is a 10-year study monitoring trends and determinants of cardiovascular disease in geographically defined populations. Data were collected from over 100 000 randomly selected participants in two risk factor surveys conducted approximately 5 years apart in 38 populations using standardized protocols. The net effects of changes in the risk factor levels were estimated using risk scores derived from longitudinal studies in the Nordic countries. The prevalence of cigarette smoking decreased among men in most populations, but the trends for women varied. The prevalence of hypertension declined in two-thirds of the populations. Changes in the prevalence of raised total cholesterol were small but highly correlated between the genders (r = 0.8). The prevalence of obesity increased in three-quarters of the populations for men and in more than half of the populations for women. In almost half of the populations there were statistically significant declines in the estimated coronary risk for both men and women, although for Beijing the risk score increased significantly for both genders. The net effect of the changes in the risk factor levels in the 1980s in most of the study populations of the WHO MONICA Project is that the rates of coronary disease are predicted to decline in the 1990s.