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Birth Rate (birth + rate)
Kinds of Birth Rate Selected AbstractsVladimir Putin on Raising Russia's Birth RatePOPULATION AND DEVELOPMENT REVIEW, Issue 2 2006Article first published online: 26 JUN 200 The total fertility rate in what is now the Russian Federation has been below replacement level during much of the last 40 years. By the late 1990s it was barely above 1.2 children per woman. There may have been some recovery since: the United Nations estimate for 2000,05 is 1.33. Other reports set the 2004 rate at 1.17. Countries elsewhere in Europe have fertility levels that are equally low or even lower, but the Russian demographic predicament is aggravated by mortality that is exceptionally high by modern standards. Thus, despite large-scale net immigration (mostly due to return of ethnic Russians from other republics of the former Soviet Union), the population in the last decade-and-a-half has been shrinking: of late by some 700,000 persons per year. The United Nations medium estimate assumes a steady recovery of the total fertility rate to reach a level of 1.85 by 2050 and a considerable improvement in survival rates during that period,notably an increase in male life expectancy at birth of more than ten years. It also assumes further modest net immigration at a steady rate, amounting to a total of somewhat over 2 million by midcentury. Under these stipulations the projected population of Russia in 2050 would be 112 million,some 31 million below its present size. By that time, 23 percent of the population would be aged 65 and older. The government's concern with the demographic situation of the country and its intent to improve it have been manifest in various official statements, notably in the annual State of the Nation Address given by the president to the Federal Assembly (or State Duma). Formerly a subordinate theme (see the Documents item in the June 2005 issue of PDR), the issue constituted the centerpiece of the 2006 Address, delivered on 10 May in the Kremlin by President Vladimir Putin. Policies regarding health and mortality were given short shrift in the speech,road safety, bootleg alcohol, and cardiovascular diseases being singled out as areas of special concern. The president's remarks on immigration are of greater interest: immigration of skilled persons is to be encouraged. They must be educated and law-abiding and must treat the country's culture and national tradition with respect. The main focus of the address, however, was on the birth rate and policies to be introduced to raise it. (The need for an "effective demographic policy" as seen from the Kremlin was of course also voiced in the later stages of the Soviet era. See, for example, the excerpts from the addresses delivered by then Party Chairman Leonid Brezhnev and Premier Nikolai Tikhonov to the 26th Congress of the Communist Party of the Soviet Union in February 1981 that appear in the Documents item in the June 1981 issue of PDR.) In detail and specificity, and also in terms of the economic cost of the measures envisaged, Putin's speech is without parallel in addressing population policy matters by a head of state in Europe. The demo graphically relevant portion of the address is reproduced below in the English translation provided by the website of the president's office «http://www.kremlin.ru/eng». Calling Russia's demographic situation "the most acute problem facing our country today," Putin terms its causes as "well known," but lists only economic factors, presumably because these, at least in principle, lend themselves to remedial measures that the Russian government, its coffers now swollen with petrodollars, should be able to provide. His starkly economic interpretation of the problem of low fertility (in Russia apparently taking the form of convergence to a single-child pattern) may be overly optimistic. Causes of electing to have only one child may lie deeper than those Putin names: low incomes, inadequate housing, poor-quality health care and inadequate educational opportunities for children, and even lack of food. Putin's proposed policies to attack these problems in part consist of a major upgrading of existing child care benefits: to 1,500 roubles a month for the first child and 3,000 roubles for the second. The latter amount is roughly equivalent to US$113, a significant sum given Russian income levels. Maternity leave for 18 months at 40 percent of the mother's previous wage (subject to a ceiling) and compensation for the cost of preschool childcare round out the basic package proposed. Benefits are to be parity-dependent, highlighting the pronatalist intent of the measures. Thus the child benefit for the second child is to be twice as large as for the first, and payment for preschool childcare is to cover 20 percent of parental costs for the first, 50 percent for the second, and 70 percent for the third child. Putin mentions "young families" as recipients, but the payments are clearly directed to mothers. (Even the usually obligatory reference to western European,style paternity leave is missing.) The most innovative element of the proposed measures, however, is support for women who have a second birth. The state should provide such women (not the child, as called for in some European precedents) "with an initial maternity capital that will raise their social status and help resolve future problems." Citing expert opinion, Putin says that such support "should total at least 250,000 roubles [about $9,300] indexed to annual inflation." Evidently assuming, optimistically, that there will be many takers, Putin says that carrying out all these plans will require not only a lot of work but also "an immense amount of money." The measures are to be launched starting January 2007. [source] ORIGINAL ARTICLE: Live Birth Rate According to Maternal Age and Previous Number of Recurrent MiscarriagesAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009Mayumi Sugiura-Ogasawara Problem, In Japan, marital age and women's age at the first pregnancy are continuing to increase year by year. However, information concerning subsequent live birth rate according to maternal age and number of previous recurrent miscarriages is limited. Method of study, We studied a total of 1250 unexplained patients suffering two or more consecutive miscarriages. We examined the live birth rate at the first pregnancy and the cumulative success rate for birth of at least one child after examination. Results, The live birth rate of women in their 40s was 58.1%, which was similar to that of women who were 35,39 years old (58.4%) at the first pregnancy, as found after examination. From logistic regression, women's age and the number of previous miscarriages independently decreased the live birth rate in subsequent pregnancies (ps) as well as cumulative pregnancies (pc), as follows: Conclusion, The information concerning the live birth rate can be given to each patient before subsequent pregnancy. [source] The Pregnancy Rate and Live Birth Rate in Kidney Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2009J. S. Gill Fertility is one of the potential benefits for women undergoing kidney transplantation; however, population-based information about the likelihood of pregnancy and successful fetal outcome is not available. In this observational study of 16 195 female kidney transplant recipients aged 15,45 years in the United States between 1990 and 2003, we determined the pregnancy rate and live birth rate using Medicare claims data from the first three posttransplant years. The pregnancy rate was 33 per thousand female transplant recipients between 1990 and 2003 and progressively declined from 59 in 1990 to 20 in 2000. The live birth rate between 1990 and 2003 was 19 per thousand female transplant recipients and declined in parallel with the pregnancy rate. Despite a decrease in therapeutic abortions over time, the proportion of pregnancies resulting in fetal loss (45.6%) remained constant during the study due to an increase in spontaneous abortions and other causes of fetal loss. The pregnancy rate in kidney transplant recipients was markedly lower and declined more rapidly than reported in the general American population during the same period. The live birth rate was substantially lower than reported in voluntary registries of transplant recipients, and the proportion of pregnancies resulting in unexpected fetal loss increased over time. [source] ORIGINAL ARTICLE: Treatment with Tumor Necrosis Factor Inhibitors and Intravenous Immunoglobulin Improves Live Birth Rates in Women with Recurrent Spontaneous AbortionAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2008Edward E. Winger Problem, The purpose of this study was to investigate whether treatment with tumor necrosis factor (TNF) inhibitors combined with intravenous immunoglobulin (IVIG) increases live birth rates among women with recurrent spontaneous abortion (RSA) concurrently treated with anticoagulants (AC). Method of study, Seventy-five pregnancies in patients with a history of RSA were retrospectively evaluated. The population was divided into three groups: group I: 21 patients treated with AC (anticoagulants), group II: 37 patients treated with AC and IVIG, and group III: 17 patients treated with AC, IVIG and the TNF inhibitor Etanercept (Enbrel®) or Adalimumab (Humira®). In groups II and III, IVIG was administered at least once during the cycle of conception and/or at least once after a positive pregnancy test. In group III, either Adalimumab or Etanercept was administered by subcutaneous injection according to standard protocols. Statistical analysis of pregnancy outcome was performed using Fisher's exact test. Results, Patient populations in the three treatment groups were similar in terms of age, past miscarriages, inherited thrombophilia and autoimmunity. The live birth rate was 19% (4/21) in group I, 54% (20/37) in group II, and 71% (12/17) in group III. There was significant improvement in pregnancy outcome in group II versus group I (P = 0.0127) and in group III versus group I (P = 0.0026). The live birth rate in group III compared to group II was not significantly different (P = 0.3723). Side effects of AC, IVIG and TNF inhibitor treatment were minimal in these patients, and no birth defects were identified in their offspring. Conclusion, In women with RSA, addition of either IVIG or a TNF inhibitor + IVIG to the AC regimen appears to improve live birth rates compared to the treatment with AC alone. The positive effect of IVIG and TNF inhibitor therapy on pregnancy outcome merits further study in prospective clinical trials. [source] Quality matters: resource quality for hosts and the timing of epidemicsECOLOGY LETTERS, Issue 2 2009Spencer R. Hall Abstract Epidemiologists increasingly realize that species interactions (e.g. selective predation) can determine when epidemics start and end. We hypothesize here that resource quality can also strongly influence disease dynamics: epidemics can be inhibited when resource quality for hosts is too poor and too good. In three lakes, resource quality for the zooplankton host (Daphnia dentifera) was poor when fungal epidemics (Metschnikowia bicuspidata) commenced and increased as epidemics waned. Experiments using variation in algal food showed that resource quality had conflicting effects on underlying epidemiology: high-quality food induced large production of infective propagules (spores) and high birth rate but also reduced transmission. A model then illustrated how these underlying correlations can inhibit the start of epidemics (when spore production/birth rate are too low) but also catalyse their end (when transmission becomes too low). This resource quality mechanism is likely to interface with other ones controlling disease dynamics and warrants closer evaluation. [source] The ecology of virulenceECOLOGY LETTERS, Issue 10 2006Curtis M. Lively Abstract Theoretical work has shown that parasites should evolve intermediate levels of virulence. Less attention has been given to the ecology of virulence. Here I explore population-dynamic models of infection in an annual host. The infection does not kill the host; but it can decrease the number of offspring produced by the host, and the magnitude of this effect depends on host population size. Hence, ,virulence' is density dependent, and is defined here as the difference in birth rates between uninfected and infected hosts, divided by the birth rate of uninfected hosts. The results suggest that infection can be highly virulent at the host's equilibrium density, even though the parasite has no effect on the host's intrinsic birth rate. The results also suggest that parasites may help to stabilize host population dynamics. In general, the impact of infection may be underestimated in natural populations. [source] The Effects of a Baby Boom on Stock Prices and Capital Accumulation in the Presence of Social SecurityECONOMETRICA, Issue 2 2003Andrew B. Abel Is the stock market boom a result of the baby boom? This paper develops an overlapping generations model in which a baby boom is modeled as a high realization of a random birth rate, and the price of capital is determined endogenously by a convex cost of adjustment. A baby boom increases national saving and investment and thus causes an increase in the price of capital. The price of capital is mean,reverting so the initial increase in the price of capital is followed by a decrease. Social Security can potentially affect national saving and investment, though in the long run, it does not affect the price of capital. [source] DEMOGRAPHIC SHIFT AND PROJECTED LABOUR SHORTAGE IN CHINAECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 3 2007INGRID NIELSEN As a result of China's family planning policy of ,raising population quality and controlling population size' initiated in the late 1970s, China has accomplished a population transition from high birth rate, low mortality rate and high population growth to low birth rate, low mortality rate and low population growth within a remarkably short timeframe. Along with this population transition, however, comes a shift in population age structure, with a rapid increase in the proportion of elderly people. This paper explores the implications of China's demographic shift for labour supply and suggests policy changes to target an emerging labour shortage. [source] Incidence and geographical distribution of sudden infant death syndrome in relation to content of nitrate in drinking water and groundwater levelsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2001M. George Background Previous studies indicate that the enteral bacterial urease is inhibited in victims of sudden infant death syndrome (SIDS). One possible inhibitor of this bacterial activity is nitrate. If ambient pollution by nitrate is involved in the etiology of SIDS only a fraction of the nitrate concentration not infrequently found in drinking water would be enough for this inhibition. Methods Occurrence of SIDS (n = 636) in Sweden during the period 1990 through 1996 were analysed regarding geographical and seasonal distribution in relation to the nitrate concentration in drinking water and changes in the groundwater level. Results Both the birth rate and the incidence of SIDS decreased during the study period. One quarter of the municipalities constituting 11% of the population had no cases, the maximum incidence being 6·5 per 1000 live births. Seasonality: The northernmost parts of the country had its highest incidence when the rest of the country had its lowest incidence, and the occurrence of individual deaths was associated with the recharge of groundwater which increases its nitrate content. The local incidence of SIDS was correlated (rs = 0·34,0·87) to maximally recorded concentrations of nitrate in drinking water. Conclusions The seasonal distribution of SIDS was widely different from the south to the north of the country and seems to be associated with differences in the groundwater level changes subsequent to precipitation, frost penetration, and melting of snow. Use of drinking water with high peak concentrations or great variations in nitrate concentration was correlated to the incidence of SIDS. [source] Vector Autoregression (Var) , An Approach to Dynamic analysis of Geographic ProcessesGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 2 2001Max Lu Vector autoregression (VAR) is a widely used econometric technique for multivariate time series modelling. This paper shows that with several very attractive features, VAR may also provide a valuable tool for analysing the dynamics among geographic processes and for spatial autoregressive modelling. After a brief discussion of the VAR approach, a VAR model for the dynamics of the US population between 1910 and 1990 is estimated and interpreted to illustrate the techniques. The VAR makes it possible to view the interactions among the four variables used in the model (total population, birth rate, immigration and per capita GNP) more adequately. The paper then discusses recent developments in the VAR methodology such as Bayesian vector autoregression (BVAR), spatial prior for regional modelling and cointegration, as well as the limitations and problems that arise from the application of VARs. [source] Impact of the post-World War II generation on intensive care needs in NorwayACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010J. H. LAAKE Background: A high birth rate during the first two decades following World War II has increased the proportion of elderly people in present-day society and, consequently, the demand for health-care services. The impact on intensive care services may become dramatic because the age distribution of critically ill patients is skewed towards the elderly. We have used registry data and population statistics to forecast the demand for intensive care services in Norway up until the year 2025. Methods: Data collected by the Norwegian intensive care registry (NIR), showing the age distribution in Norwegian intensive care units (ICU) during the years 2006 and 2007, were used with three different Norwegian prognostic models of population growth for the years 2008,2025 to compute the expected increase in intensive care unit bed-days (ICU bed-days). Results: The elderly were overrepresented in Norwegian ICUs in 2006,2007, with patients from 60 to 79 years of age occupying 44% of ICU bed-days. Population growth from 2008 to 2025 was estimated to be from 11.1 to 26.4%, depending on the model used. Growth will be much larger in the age group 60,79 years. Other factors kept unchanged, this will result in an increase in the need for intensive care (ICU bed-days) of between 26.1 and 36.9%. Conclusion: The demand for intensive care beds will increase markedly in Norwegian hospitals in the near future. This will have serious implications for the planning of infrastructure, education of health care personnel, as well as financing of our health care system. [source] Demographic models and the management of endangered species: a case study of the critically endangered Seychelles magpie robinJOURNAL OF APPLIED ECOLOGY, Issue 5 2003Ken Norris Summary 1Demographic models are assuming an important role in management decisions for endangered species. Elasticity analysis and scope for management analysis are two such applications. Elasticity analysis determines the vital rates that have the greatest impact on population growth. Scope for management analysis examines the effects that feasible management might have on vital rates and population growth. Both methods target management in an attempt to maximize population growth. 2The Seychelles magpie robin Copsychus sechellarum is a critically endangered island endemic, the population of which underwent significant growth in the early 1990s following the implementation of a recovery programme. We examined how the formal use of elasticity and scope for management analyses might have shaped management in the recovery programme, and assessed their effectiveness by comparison with the actual population growth achieved. 3The magpie robin population doubled from about 25 birds in 1990 to more than 50 by 1995. A simple two-stage demographic model showed that this growth was driven primarily by a significant increase in the annual survival probability of first-year birds and an increase in the birth rate. Neither the annual survival probability of adults nor the probability of a female breeding at age 1 changed significantly over time. 4Elasticity analysis showed that the annual survival probability of adults had the greatest impact on population growth. There was some scope to use management to increase survival, but because survival rates were already high (> 0·9) this had a negligible effect on population growth. Scope for management analysis showed that significant population growth could have been achieved by targeting management measures at the birth rate and survival probability of first-year birds, although predicted growth rates were lower than those achieved by the recovery programme when all management measures were in place (i.e. 1992,95). 5Synthesis and applications. We argue that scope for management analysis can provide a useful basis for management but will inevitably be limited to some extent by a lack of data, as our study shows. This means that identifying perceived ecological problems and designing management to alleviate them must be an important component of endangered species management. The corollary of this is that it will not be possible or wise to consider only management options for which there is a demonstrable ecological benefit. Given these constraints, we see little role for elasticity analysis because, when data are available, a scope for management analysis will always be of greater practical value and, when data are lacking, precautionary management demands that as many perceived ecological problems as possible are tackled. [source] Cost-effectiveness analysis of triple test in second-trimester maternal serum screening for Down's syndrome: an experience from Taiwan with decreasing birth rate but increasing population of old pregnant womenJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2008Hsiao-Lin Hwa PhD Objectives, We intended to assess the cost-effectiveness of adding unconjugated oestriol (uE3) in maternal serum screening for Down's syndrome in Taiwan, where there is a decreasing birth rate but an increasing trend of old women having pregnancies. Methods, We used logistic regressions to estimate the risk of Down's syndrome with maternal age and different combinations of biomarkers. Cost-effectiveness analysis was presented in terms of the average and incremental cost-effectiveness ratios. Sensitivity analyses with different parameters were performed. Results, Given a cut-off point of 1:270 for the confirmation of Down's syndrome with amniocentesis, the average cost per case averted for maternal age above 35 years only, double test [alpha-fetoprotein (AFP) and human chorionic gonadotrophin (hCG)] and triple test (AFP, hCG and uE3) were estimated as $14 561, $42 367 and $37 424. The additional costs per case averted for double test and triple test (compared with maternal age above 35 years) were $135 950 and $77 394, respectively. The additional cost per case averted for triple test was $15 199 compared with double test. Conclusions, The performance of triple test is not only more effective in detecting Down's syndrome cases but also more cost-effective than double test in this study. [source] Maternal parity affects neonatal survival rate in a colony of captive bred baboons (Papio hamadryas)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 5 2008Neroli Sunderland Abstract Background, Non-human primates, particularly baboons, are valuable as animal models for reproductive research, because of their similarity to humans. Knowledge of colony-specific pregnancy and neonatal outcomes is essential for interpretation of such research. Methods, A retrospective review of the reproductive records of the Australian National Baboon Colony (ANBC) from 1994 to 2006 was performed. Results, The overall live birth rate was over 70% of recognized pregnancies. Pregnancy loss was due to equal proportions of spontaneous abortion and stillbirth, and was not affected by maternal age or parity. Stillbirth rates were increased by the use of animals in novel late pregnancy experimental protocols. Neonatal mortality rates were low overall, but significantly higher in primiparous compared with multiparous mothers (P < 0.05). There were no cases of maternal mortality. Conclusions, The success of the ANBC breeding programme is demonstrated by the low rate of pregnancy loss, high neonatal survival rate and lack of maternal mortality. [source] Influence of obstetric factors on the yield of mononuclear cells, CD34+ cell count and volume of placental/umbilical cord bloodJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 1 2010Atsuko Omori Abstract Aim:, Placental/umbilical cord blood (CB) has been used increasingly not only for transplantations, but also in the field of life science research. However, little information is available on the biological characteristics of CB units collected in rural areas because no medical facilities are affiliated with CB banks. Little attention has been paid to the collection of CB units in rural areas compared to CB collected in metropolitan areas. CB is a precious source for life science research due to the recent low birth rate in Japan. Therefore, to efficiently utilize CB units, the purpose of the present study was to investigate the optimum obstetric factors associated with a higher yield of mononuclear/CD34+ cells per CB unit. Methods:, CB units were collected at a single hospital (Hirosaki National Hospital). A total of 126 CB units from 105 vaginal deliveries and 21 cesarean section deliveries were available for cell separation within 24 h. Mononuclear low-density (LD) cells were separated using Ficoll-Paque and then processed for CD34+ cell enrichment using magnetic cell sorting. Associations between the maternal/neonatal factors and the yield of LD/CD34+ cells were analyzed. Results:, Despite the larger net weight of CB collected from cesarean section deliveries, the total number of LD cells collected from vaginal deliveries was significantly higher than that collected from cesarean section deliveries. The total number of LD cells per CB unit from primigravidae was significantly higher compared with that collected from from multigravidae. Conclusion:, CB units from vaginal deliveries of primigravidae may be more favorable because they contain a higher yield of mononuclear cells. [source] Does continuous use of metformin throughout pregnancy improve pregnancy outcomes in women with polycystic ovarian syndrome?JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2008Fauzia Haq Nawaz Abstract Aim:, Polycystic ovarian syndrome (PCOS) is one of the most common endocrinopathies in women of reproductive age. It is associated with hyperinsulinemia and insulin resistance which is further aggravated during pregnancy. This mechanism has a pivotal role in the development of various complications during pregnancy. In the past few years, metformin, an insulin sensitizer, has been extensively evaluated for induction of ovulation. Its therapeutic use during pregnancy is, however, a recent strategy and is a debatable issue. At present, evidence is inadequate to support the long-term use of insulin-sensitizing agents during pregnancy. It is a challenge for both clinicians and researchers to provide good evidence of the safety of metformin for long-term use and during pregnancy. This study aimed to evaluate pregnancy outcomes in women with PCOS who conceived while on metformin treatment, and continued the medication for a variable length of time during pregnancy. Methods:, This case-control study was conducted from January 2005 to December 2006 at the antenatal clinics of the Department of Obstetrics and Gynecology, Aga Khan University, Karachi, Pakistan. The sample included 137 infertile women with PCOS; of these, 105 conceived while taking metformin (cases), while 32 conceived spontaneously without metformin (controls). Outcomes were measured in three groups of cases which were formed according to the duration of use of metformin during pregnancy. Comparison was made between these groups and women with PCOS who conceived spontaneously. Results:, All 137 women in this study had a confirmed diagnosis of PCOS (Rotterdam criteria). These women were followed up during their course of pregnancy; data forms were completed once they had delivered. Cases were divided into three groups: group A, 40 women who stopped metformin between 4,16 weeks of pregnancy; group B, 20 women who received metformin up until 32 weeks of gestation; and group C; 45 women who continued metformin throughout pregnancy. All the groups were matched by age, height and weight. Comparison was in terms of early and late pregnancy complications, intrauterine growth restriction and live birth rates. In groups A, B and C the rate of pregnancy-induced hypertension/pre-eclampsia was 43.7%, 33% and 13.9% respectively (P < 0.020). Rates of gestational diabetes requiring insulin treatment in groups A and B were 18.7% and 33.3% compared to 2.5% in group C (P < 0.004). The rate of intrauterine growth restriction was significantly low in group C: 2.5% compared to 19.2% and 16.6% in groups A and B respectively (P < 0.046). Frequency of preterm labor and live birth rate was significantly better in group C compared to groups A and B. Overall rate of miscarriages was 7.8%. Controls were comparable to group A in terms of early and late pregnancy complications. Conclusion:, In women with PCOS, continuous use of metformin during pregnancy significantly reduced the rate of miscarriage, gestational diabetes requiring insulin treatment and fetal growth restriction. No congenital anomaly, intrauterine death or stillbirth was reported in this study. [source] Backward Intergenerational Goods and Endogenous FertilityJOURNAL OF PUBLIC ECONOMIC THEORY, Issue 5 2008JOHN WILLIAM HATFIELD This paper characterizes the consequences of introducing the public provision of intergenerational goods to the elderly in a model with endogenous fertility. With exogenous fertility, it has been shown that the government can mandate the first-best outcome by simply imposing the socially optimal transfer. By contrast, with endogenous fertility, the government can no longer enforce this outcome. This is due, in part, to the effects of mandatory provision on the birth rate. However, taxes may still have a salubrious effect on social welfare as they can eliminate particularly bad equilibria. [source] Populating the Galaxy with low-mass X-ray binariesMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2006Paul D. Kiel ABSTRACT We perform binary population-synthesis calculations to investigate the incidence of low-mass X-ray binaries (LMXBs) and their birth rate in the Galaxy. We use a binary-evolution algorithm that models all the relevant processes including tidal circularization and synchronization. Parameters in the evolution algorithm that are uncertain and may affect X-ray binary formation are allowed to vary during the investigation. We agree with previous studies that under standard assumptions of binary evolution the formation rate and number of black hole (BH) LMXBs predicted by the model are more than an order of magnitude less than what is indicated by observations. We find that the common-envelope process cannot be manipulated to produce significant numbers of BH LMXBs. However, by simply reducing the mass-loss rate from helium stars adopted in the standard model, to a rate that agrees with the latest data, we produce a good match to the observations. Including LMXBs that evolve from intermediate-mass systems also leads to favourable results. We stress that constraints on the X-ray binary population provided by observations are used here merely as a guide as surveys suffer from incompleteness and much uncertainty is involved in the interpretation of results. [source] Star cluster ecology , V. Dissection of an open star cluster: spectroscopyMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2004Simon F. Portegies Zwart ABSTRACT We have modelled in detail the evolution of rich open star clusters such as NGC 2516, NGC 2287, Pleiades, Praesepe, Hyades, NGC 2660 and 3680, using simulations that include stellar dynamics as well as the effects of stellar evolution. The dynamics is modelled via direct N -body integration, while the evolution of single stars and binaries is followed through the use of fitting formulae and recipes. The feedback of stellar and binary evolution on the dynamical evolution of the stellar system is taken into account self-consistently. Our model clusters dissolve in the tidal field of the Galaxy in a time-span of the order of a billion years. The rate of mass loss is rather constant, ,1 M, per million years. The binary fraction at first is nearly constant in time, then increases slowly near the end of a cluster's lifetime. For clusters which are more than about 108 yr old the fractions of stars in the form of binaries, giants and merger products in the inner few core radii are considerably higher than in the outer regions, beyond the cluster's half-mass radius. When stars with masses ,2 M, escape from the cluster, they tend to do so with velocities higher than average. The stellar merger rate in our models is roughly one per 30 million years. Most mergers are the result of unstable mass transfer in close binaries (,70 per cent), but a significant minority are caused by direct encounters between single and binary stars. While most mergers occur within the cluster core, even beyond the half-mass radius stellar mergers occasionally take place. We notice a significant birth rate of X-ray binaries, most containing a white dwarf as the mass acceptor. We also find one high-mass X-ray binary with a neutron-star accretor. If formed and retained, black holes participate in many (higher-order) encounters in the cluster centre, resulting in a large variety of exotic binaries. The persistent triple and higher-order systems formed in our models by dynamical encounters between binaries and single stars are not representative for the multiple systems observed in the Galactic disc. We conclude that the majority of multiples in the disc probably formed when the stars were born, rather than through later dynamical interactions. [source] Secular trends in socio-economic status and the implications for preterm birthPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 3 2006John M. D. Thompson Summary The rate of preterm birth in the developed world has been shown to be increasing, in part attributable to obstetric intervention. It has been suggested that this may be a differential increase between socio-economic groups. We aimed to assess whether the preterm rate in Norway is different in socio-economic groups defined by maternal education, and to determine the extent to which a difference is attributable to a socio-economic differential in obstetrical intervention, in terms of caesarean section or induction of labour. We used data from the Medical Birth Registry of Norway from 1980 to 1998 with preterm rate as the outcome and maternal educational level, marital status and obstetric intervention as exposure variables. In multivariable analyses, adjustment was made for maternal age, year of birth and birth order, and secular trends were assessed according to year of birth. The preterm birth rate was highest in the lowest socio-economic group. An increase of 25.2% in the preterm rate was seen over the observation period. No apparent differential was seen in the increase of the crude preterm rates between socio-economic groups, although in multivariable analyses there was a significant interaction between socio-economic group and time, implying a stronger effect of low education towards the end of the observation period attributable to demographic change. In conclusion, the preterm birth rate increased over time, but was mainly due to an increase in obstetric interventions. No closing of the gap between socio-economic groups was observed. [source] Outcome of 122 pregnancies in essential thrombocythemia patients: A report from the Italian registryAMERICAN JOURNAL OF HEMATOLOGY, Issue 10 2009Lorella Melillo Pregnancy is a high-risk event in women with essential thrombocythemia (ET). This observational study evaluated pregnancy outcome in ET patients focusing on the potential impact of aspirin (ASA) or interferon alpha (IFN) treatment during pregnancy. We retrospectively analyzed 122 pregnancies in 92 women consecutively observed in the last 10 years in 17 centers of the Italian thrombocythemia registry (RIT). The live birth rate was 75.4% (92/122 pregnancies). The risk of spontaneous abortion was 2.5-fold higher than in the control population (P < 0.01). ASA did not affect the live birth rate (71/93, 76.3% vs. 21/29, 72.4%, P = 0.67). However, IFN treatment during pregnancy was associated with a better outcome than was management without IFN (live births 19/20, 95% vs. 73/102, 71.6%, P = 0.025), and this finding was supported by multivariate analysis (OR: 0.10; 95% CI: 0.013,0.846, P = 0.034). The JAK2 V617F mutation was associated with a poorer outcome (fetal losses JAK2 V617F positive 9/25, 36% vs. wild type 2/24, 8.3%, P = 0.037), and this association was still significant after multivariate analysis (OR: 6.19; 95% CI: 1.17,32.61; P = 0.038). No outcome concordance between first and second pregnancies was found (P = 0.30). Maternal complications occurred in 8% of cases. In this retrospective study, in consecutively observed pregnant ET patients, IFN treatment was associated with a higher live birth rate, while ASA treatment was not. In addition, the JAK2 V617F mutation was confirmed to be an adverse prognostic factor. Am. J. Hematol. 2009. © 2009 Wiley-Liss, Inc. [source] Vladimir Putin on Raising Russia's Birth RatePOPULATION AND DEVELOPMENT REVIEW, Issue 2 2006Article first published online: 26 JUN 200 The total fertility rate in what is now the Russian Federation has been below replacement level during much of the last 40 years. By the late 1990s it was barely above 1.2 children per woman. There may have been some recovery since: the United Nations estimate for 2000,05 is 1.33. Other reports set the 2004 rate at 1.17. Countries elsewhere in Europe have fertility levels that are equally low or even lower, but the Russian demographic predicament is aggravated by mortality that is exceptionally high by modern standards. Thus, despite large-scale net immigration (mostly due to return of ethnic Russians from other republics of the former Soviet Union), the population in the last decade-and-a-half has been shrinking: of late by some 700,000 persons per year. The United Nations medium estimate assumes a steady recovery of the total fertility rate to reach a level of 1.85 by 2050 and a considerable improvement in survival rates during that period,notably an increase in male life expectancy at birth of more than ten years. It also assumes further modest net immigration at a steady rate, amounting to a total of somewhat over 2 million by midcentury. Under these stipulations the projected population of Russia in 2050 would be 112 million,some 31 million below its present size. By that time, 23 percent of the population would be aged 65 and older. The government's concern with the demographic situation of the country and its intent to improve it have been manifest in various official statements, notably in the annual State of the Nation Address given by the president to the Federal Assembly (or State Duma). Formerly a subordinate theme (see the Documents item in the June 2005 issue of PDR), the issue constituted the centerpiece of the 2006 Address, delivered on 10 May in the Kremlin by President Vladimir Putin. Policies regarding health and mortality were given short shrift in the speech,road safety, bootleg alcohol, and cardiovascular diseases being singled out as areas of special concern. The president's remarks on immigration are of greater interest: immigration of skilled persons is to be encouraged. They must be educated and law-abiding and must treat the country's culture and national tradition with respect. The main focus of the address, however, was on the birth rate and policies to be introduced to raise it. (The need for an "effective demographic policy" as seen from the Kremlin was of course also voiced in the later stages of the Soviet era. See, for example, the excerpts from the addresses delivered by then Party Chairman Leonid Brezhnev and Premier Nikolai Tikhonov to the 26th Congress of the Communist Party of the Soviet Union in February 1981 that appear in the Documents item in the June 1981 issue of PDR.) In detail and specificity, and also in terms of the economic cost of the measures envisaged, Putin's speech is without parallel in addressing population policy matters by a head of state in Europe. The demo graphically relevant portion of the address is reproduced below in the English translation provided by the website of the president's office «http://www.kremlin.ru/eng». Calling Russia's demographic situation "the most acute problem facing our country today," Putin terms its causes as "well known," but lists only economic factors, presumably because these, at least in principle, lend themselves to remedial measures that the Russian government, its coffers now swollen with petrodollars, should be able to provide. His starkly economic interpretation of the problem of low fertility (in Russia apparently taking the form of convergence to a single-child pattern) may be overly optimistic. Causes of electing to have only one child may lie deeper than those Putin names: low incomes, inadequate housing, poor-quality health care and inadequate educational opportunities for children, and even lack of food. Putin's proposed policies to attack these problems in part consist of a major upgrading of existing child care benefits: to 1,500 roubles a month for the first child and 3,000 roubles for the second. The latter amount is roughly equivalent to US$113, a significant sum given Russian income levels. Maternity leave for 18 months at 40 percent of the mother's previous wage (subject to a ceiling) and compensation for the cost of preschool childcare round out the basic package proposed. Benefits are to be parity-dependent, highlighting the pronatalist intent of the measures. Thus the child benefit for the second child is to be twice as large as for the first, and payment for preschool childcare is to cover 20 percent of parental costs for the first, 50 percent for the second, and 70 percent for the third child. Putin mentions "young families" as recipients, but the payments are clearly directed to mothers. (Even the usually obligatory reference to western European,style paternity leave is missing.) The most innovative element of the proposed measures, however, is support for women who have a second birth. The state should provide such women (not the child, as called for in some European precedents) "with an initial maternity capital that will raise their social status and help resolve future problems." Citing expert opinion, Putin says that such support "should total at least 250,000 roubles [about $9,300] indexed to annual inflation." Evidently assuming, optimistically, that there will be many takers, Putin says that carrying out all these plans will require not only a lot of work but also "an immense amount of money." The measures are to be launched starting January 2007. [source] ORIGINAL ARTICLE: Live Birth Rate According to Maternal Age and Previous Number of Recurrent MiscarriagesAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009Mayumi Sugiura-Ogasawara Problem, In Japan, marital age and women's age at the first pregnancy are continuing to increase year by year. However, information concerning subsequent live birth rate according to maternal age and number of previous recurrent miscarriages is limited. Method of study, We studied a total of 1250 unexplained patients suffering two or more consecutive miscarriages. We examined the live birth rate at the first pregnancy and the cumulative success rate for birth of at least one child after examination. Results, The live birth rate of women in their 40s was 58.1%, which was similar to that of women who were 35,39 years old (58.4%) at the first pregnancy, as found after examination. From logistic regression, women's age and the number of previous miscarriages independently decreased the live birth rate in subsequent pregnancies (ps) as well as cumulative pregnancies (pc), as follows: Conclusion, The information concerning the live birth rate can be given to each patient before subsequent pregnancy. [source] ORIGINAL ARTICLE: Treatment with Adalimumab (Humira®) and Intravenous Immunoglobulin Improves Pregnancy Rates in Women Undergoing IVF,AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2009Edward E. Winger Problem, The purpose of this study was to investigate whether treatment with TNF-, inhibitors and/or intravenous immunoglobulin (IVIG) increases in vitro fertilization (IVF) success rates among young (<38 years) women with infertility and T helper 1/T helper 2 cytokine elevation. Method of study, Seventy-five sub-fertile women with Th1/Th2 cytokine elevation were divided into four groups: Group I: Forty-one patients using both IVIG and Adalimumab (Humira®), Group II: Twenty-three patients using IVIG, Group III: Six patients using Humira®, and Group IV: Five patients using no IVIG or Humira®. Results, The implantation rate (number of gestational sacs per embryo transferred, with an average of two embryos transferred by cycle) was 59% (50/85), 47% (21/45), 31% (4/13) and 0% (0/9) for groups I, II, III and IV respectively. The clinical pregnancy rate (fetal heart activity per IVF cycle started) was 80% (33/41), 57% (13/23), 50% (3/6) and 0% (0/5) and the live birth rate was 73% (30/41), 52% (12/23), 50% (3/6) and 0% (0/5) respectively. There was a significant improvement in implantation, clinical pregnancy and live birth rates for group I versus group IV (P = 0.0007, 0.0009, and 0.003, respectively) and for group II versus group IV (P = 0.009, 0.04 and 0.05, respectively). Conclusion, The use of a TNF-, inhibitor and IVIG significantly improves IVF outcome in young infertile women with Th1/Th2 cytokine elevation. [source] Is the Paternal Mononuclear Cells' Immunization a Successful Treatment for Recurrent Spontaneous Abortion?AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2000R. RAMHORST PROBLEM: Alloimmunization as a treatment for recurrent spontaneous abortion (RSA) is still controversial due to the lack of enough controls to evaluate its effectiveness. The present study was conducted to compare the live birth rate in the presence or absence of immunotherapy. METHOD OF STUDY: Ninety-two women with RSA (79 primary [PA] and 13 secondary aborters[SA]) received immunotherapy. Thirty-seven RSA couples not receiving paternal alloimmunization, constituted the "control" group. RESULTS: The pregnancy rate in alloimmunized was 58 vs 46% in the control group. The live birth increased from 71% in the controls to 88% after immunotherapy. The alloimmunization induced mixed lymphocyte reaction blocking factors (MLR BFs) in 79% of women. However, they were also present in 83% of immunized women experiencing a new abortion. CONCLUSION: These results indicate that alloimmunization may be useful in the treatment of RSA. [source] The Pregnancy Rate and Live Birth Rate in Kidney Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2009J. S. Gill Fertility is one of the potential benefits for women undergoing kidney transplantation; however, population-based information about the likelihood of pregnancy and successful fetal outcome is not available. In this observational study of 16 195 female kidney transplant recipients aged 15,45 years in the United States between 1990 and 2003, we determined the pregnancy rate and live birth rate using Medicare claims data from the first three posttransplant years. The pregnancy rate was 33 per thousand female transplant recipients between 1990 and 2003 and progressively declined from 59 in 1990 to 20 in 2000. The live birth rate between 1990 and 2003 was 19 per thousand female transplant recipients and declined in parallel with the pregnancy rate. Despite a decrease in therapeutic abortions over time, the proportion of pregnancies resulting in fetal loss (45.6%) remained constant during the study due to an increase in spontaneous abortions and other causes of fetal loss. The pregnancy rate in kidney transplant recipients was markedly lower and declined more rapidly than reported in the general American population during the same period. The live birth rate was substantially lower than reported in voluntary registries of transplant recipients, and the proportion of pregnancies resulting in unexpected fetal loss increased over time. [source] Restoring a keystone predator may endanger a prey species in a human-altered ecosystem: the return of the snow leopard to Sagarmatha National ParkANIMAL CONSERVATION, Issue 6 2009S. Lovari Abstract Twenty-five years ago, the snow leopard Uncia uncia, an endangered large cat, was eliminated from what is now Sagarmatha National Park (SNP). Heavy hunting pressure depleted that area of most medium,large mammals, before it became a park. After three decades of protection, the cessation of hunting and the recovery of wild ungulate populations, snow leopards have recently returned (four individuals). We have documented the effects of the return of the snow leopard on the population of its main wild prey, the Himalayan tahr Hemitragus jemlahicus, a ,near-threatened' caprin. Signs of snow leopard presence were recorded and scats were collected along a fixed trail (130 km) to assess the presence and food habits of the snow leopard in the Park, from 2004 to 2006. Himalayan tahr, the staple of the diet, had a relative occurrence of 48% in summer and 37% in autumn, compared with the next most frequent prey, musk deer Moschus chrysogaster (summer: 20%; autumn: 15%) and cattle (summer: 15%; autumn: 27%). In early summer, the birth rate of tahr (young-to-female ratio: 0.8,0.9) was high. The decrease of this ratio to 0.1,0.2 in autumn implied that summer predation concentrated on young tahr, eventually altering the population by removing the kid cohort. Small populations of wild Caprinae, for example the Himalayan tahr population in SNP, are sensitive to stochastic predation events and may be led to almost local extinction. If predation on livestock keeps growing, together with the decrease of Himalayan tahr, retaliatory killing of snow leopards by local people may be expected, and the snow leopard could again be at risk of local extinction. Restoration of biodiversity through the return of a large predator has to be monitored carefully, especially in areas affected by humans, where the lack of important environmental components, for example key prey species, may make the return of a predator a challenging event. [source] The birth rate of hypospadias in the Turku area in Finland,APMIS, Issue 2 2001H. E. VIRTANEN Reports based on national registers of congenital malformations have suggested that the birth rate of hypospadias has increased during the last few decades. Register-based information may, however, have pitfalls because of changes in diagnostics, reporting accuracy and registration system. The aim of this study was to determine the current birth rate of hypospadias in Turku University Central Hospital (TUCH) in Finland. This was a prospective study on live-born boys born in TUCH from 1997 to 1999. In the total birth cohort (n=5,798) as well as in a special subcohort group (n=1,505) 0.3% of boys had hypospadias. Only one scrotal hypospadias was found in a boy who had a chromosomal anomaly. Other hypospadias were glandular or coronal. No increase was found in the birth rate of hypospadias when comparing our result with register-based data of boys born in Finland during the years 1970 to 1986 and surgically treated for hypospadias by the age of 8 years. No difference was found either from malformation register-based data concerning the nationwide birth rate of hypospadias during the years 1993 to 1998. Due to differences in national registration systems between countries, prospective studies with equal assessment criteria are needed in order to make reliable international comparisons. [source] Dynamics of an age-structured population drawn from a random numbers tableAUSTRAL ECOLOGY, Issue 4 2000Bertram G. Murray JR Abstract I constructed age-structured populations by drawing numbers from a random numbers table, the constraints being that within a cohort each number be smaller than the preceding number (indicating that some individuals died between one year and the next) and that the first two-digit number following 00 or 01 ending one cohort's life be the number born into the next cohort. Populations constructed in this way showed prolonged existence with total population numbers fluctuating about a mean size and with long-term growth rate (r) , 0. The populations' birth rates and growth rates and the females' per capita fecundity decreased significantly with population size, whereas the death rates showed no significant relationship to population size. These results indicate that age-structured populations can persist for long periods of time with long-term growth rates of zero in the absence of negative-feedback loops between a population's present or prior density and its birth rate, growth rate, and fecundity, contrary to the assumption of density-dependent regulation hypotheses. Thus, a long-term growth rate of zero found in natural populations need not indicate that a population's numbers are regulated by density-dependent factors. [source] Dynamics of an age-structured population drawn from a random numbers tableAUSTRAL ECOLOGY, Issue 4 2000BERTRAM G. MURRAY JR Abstract I constructed age-structured populations by drawing numbers from a random numbers table, the constraints being that within a cohort each number be smaller than the preceding number (indicating that some individuals died between one year and the next) and that the first two-digit number following 00 or 01 ending one cohort's life be the number born into the next cohort. Populations constructed in this way showed prolonged existence with total population numbers fluctuating about a mean size and with long-term growth rate (r) , 0. The populations' birth rates and growth rates and the females' per capita fecundity decreased significantly with population size, whereas the death rates showed no significant relationship to population size. These results indicate that age-structured populations can persist for long periods of time with long-term growth rates of zero in the absence of negative-feedback loops between a population's present or prior density and its birth rate, growth rate, and fecundity, contrary to the assumption of density-dependent regulation hypotheses. Thus, a long-term growth rate of zero found in natural populations need not indicate that a population's numbers are regulated by density-dependent factors. [source] | ||||||||||||||||||||||||||||||||||||||||