University of Turku

About: University of Turku is a education organization based out in Turku, Finland. It is known for research contribution in the topics: Population & Galaxy. The organization has 16296 authors who have published 45124 publications receiving 1505428 citations. The organization is also known as: Turun yliopisto & Åbo universitet.

Longitudinal Reproductive Hormone Profiles in Infants: Peak of Inhibin B Levels in Infant Boys Exceeds Levels in Adult Men

Abstract: The gonads are usually considered quiescent organs in infancy and childhood. However, during the first few postnatal months of life, levels of gonadotropins and sex hormones are elevated in humans. Recent epidemiological evidence suggests that environmental factors operating perinatally may influence male reproductive health in adulthood. The early postnatal activity of the Sertoli cell, a testicular cell type that is supposed to play a major role in sperm production in adulthood is largely unknown. Recently, the peptide hormone inhibin B was shown to be a marker of Sertoli cell function in the adult male. In the adult woman, inhibin B is secreted by the granulosa cells. Longitudinal serum levels of inhibin B were measured in healthy boys (n = 15) and girls (n = 15), in cord blood, and every third month during the first 2 yr of life. In addition, serum levels of FSH, LH, and testosterone (boys) were measured in the same group of children. In boys, inhibin B, FSH, LH, and testosterone levels were all elevated at 3 months of age. However, the peak of inhibin B was unexpectedly high, into the supraadult range (mean +/- SE, 378 +/- 23 pg/mL) and persisted much longer than the elevation of FSH, LH, and testosterone. Thus, although levels of FSH, LH, and testosterone decreased into the range observed later in childhood by the age of 6-9 months, serum inhibin B levels remained elevated up to at least the age of 15 months. In girls, the hormonal pattern was generally more complex, with a high interindividual variation in levels of inhibin B, FSH, and LH within each age. In conclusion, the sustained elevation of inhibin B to supraadult levels in infant boys indicates that the neonatal period may be a developmental window important for Sertoli cell proliferation and maturation. Thus, the gonads may be potentially vulnerable to exogenous endocrine interference, e.g. from environmental factors during this period of life. Measurement of serum levels of inhibin B in infants may give clinical clues about developmental deficiencies in the gonads that otherwise only become apparent around puberty or later in life.

Magic discovery of very high energy emission from the fsrq pks 1222+21

Abstract: Very high energy (VHE) gamma-ray emission from the flat spectrum radio quasar (FSRQ) PKS 1222+ 21 (4C 21.35, z = 0.432) was detected with the MAGIC Cherenkov telescopes during a short observation (similar to 0.5 hr) performed on 2010 June 17. The MAGIC detection coincides with high-energy MeV/ GeV gamma-ray activity measured by the Large Area Telescope (LAT) on board the Fermi satellite. The VHE spectrum measured by MAGIC extends from about 70 GeV up to at least 400 GeV and can be well described by a power-law dN/dE proportional to E-Gamma with a photon index Gamma = 3.75 +/- 0.27(stat) +/- 0.2(syst). The averaged integral flux above 100 GeV is (4.6 +/- 0.5) x 10(-10) cm(-2) s(-1) (similar to 1 Crab Nebula flux). The VHE flux measured by MAGIC varies significantly within the 30 minute exposure implying a flux doubling time of about 10 minutes. The VHE and MeV/GeV spectra, corrected for the absorption by the extragalactic background light (EBL), can be described by a single power law with photon index 2.72 +/- 0.34 between 3 GeV and 400 GeV, and is consistent with emission belonging to a single component in the jet. The absence of a spectral cutoff constrains the gamma-ray emission region to lie outside the broad-line region, which would otherwise absorb the VHE gamma-rays. Together with the detected fast variability, this challenges present emission models from jets in FSRQs. Moreover, the combined Fermi/LAT and MAGIC spectral data yield constraints on the density of the EBL in the UV-optical to near-infrared range that are compatible with recent models.

Global Entrepreneurship Monitor: 2004 Report on Women and Entrepreneurship

Abstract: The role women play in entrepreneurial activity in the world economy is examined, as well as the factors that influence women’s participation in this activity.The analysis involves four types of data collection.The first comes from sampling randomly selected adults in the 34 countries examined.Second, interviews are conducted with 50 different experts in each country.These same experts are then asked to complete a standardized questionnaire.Data from international sources such as the World Bank, the International Monetary Fund, and the United Nations are also collected.These data sets are combined and analyzed to produce the measures of entrepreneurial activity discussed. Results indicate that, in every country examined,men are more involved in entrepreneurship than women.The greatest gap between the genders occurs in middle-income countries.The driving force behind women’s decisions to pursue entrepreneurial activity is the lack of other job opportunities. This is especially true in low-income nations.However, no matter the income level of the country, women who have confidence and are able to perceive business opportunities are more likely to start a new business.These new businesses tend to target existing markets, use known technology, and utilize less start-up capital, which indicates that women are more conservative in their entrepreneurial activity. (SRD)

Genome-wide associations for birth weight and correlations with adult disease

Abstract: Birth weight (BW) has been shown to be influenced by both fetal and maternal factors and in observational studies is reproducibly associated with future risk of adult metabolic diseases including type 2 diabetes (T2D) and cardiovascular disease1. These life-course associations have often been attributed to the impact of an adverse early life environment. Here, we performed a multi-ancestry genome-wide association study (GWAS) meta-analysis of BW in 153,781 individuals, identifying 60 loci where fetal genotype was associated with BW (P < 5 × 10−8). Overall, approximately 15% of variance in BW was captured by assays of fetal genetic variation. Using genetic association alone, we found strong inverse genetic correlations between BW and systolic blood pressure (Rg = −0.22, P = 5.5 × 10−13), T2D (Rg = −0.27, P = 1.1 × 10−6) and coronary artery disease (Rg = −0.30, P = 6.5 × 10−9). In addition, using large -cohort datasets, we demonstrated that genetic factors were the major contributor to the negative covariance between BW and future cardiometabolic risk. Pathway analyses indicated that the protein products of genes within BW-associated regions were enriched for diverse processes including insulin signalling, glucose homeostasis, glycogen biosynthesis and chromatin remodelling. There was also enrichment of associations with BW in known imprinted regions (P = 1.9 × 10−4). We demonstrate that life-course associations between early growth phenotypes and adult cardiometabolic disease are in part the result of shared genetic effects and identify some of the pathways through which these causal genetic effects are mediated.