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ABSTRACT: Large European aspen (Populus tremula) trees host hundreds of species of which many are threatened species of conifer-dominated, old-growth boreal forests. Aspen is also one of the deciduous tree [...]

The influence of positive sensory experience with a (purportedly) genetically modified organism (GMO)-based food product on the consumers' attitude towards the use of GMOs in food production is examined. Results based on the experimental analysis revealed that the attitude towards GMO in food production is less negative and type of starter culture used (GM/conventional) has less impact on the buying intentions of experimental group.

Ovulation probably will not occur if a woman forgets to take her birth control pills for up to three days. Researchers used ultrasound scans to measure ovulation in 99 women who were randomly assigned to one of three combined oral contraceptive regimens. During an interval of 10 days in which the women did not take their pills, follicle stimulating hormone and estradiol levels increased. This increases the chance of ovulation, but evidence of beginning ovulation was found in only 24% to 40% of the women, depending on which contraceptive regimen they were on.

Introduction Menorrhagia is a major reason for hysterectomy among fertile women.[1] Abnormal uterine bleeding is a common reason for consulting general practitioners.[2] Until recently, medical treatment has been disappointing,[3 4] [...]

Estrogen implants combined with a progestin-releasing intrauterine device worked effectively as postmenopausal replacement therapy. Thirty-six postmenopausal women received one or three estrogen implants, and a levonorgestrel-releasing IUD was inserted. Four women, all with only a single estrogen implant, withdrew from the study because of the return of menopausal symptoms. Three women with three estrogen implants also discontinued therapy. One complained of loss of libido at ten weeks, and another discontinued at 9 months for sensations of swelling. The third woman discontinued at 13 months for uncontrolled bleeding that turned out to be caused by a cervical polyp. By the end of the year-long observation period, 72% of the group had had no bleeding or spotting within the prior three months. This combination of therapies offers the convenience of requiring no daily effort.

Subdermal estradiol implants used with intrauterine progestin appear to offer a safe and effective means of administering hormone replacement therapy to postmenopausal women. Estradiol is an estrogen, a hormonal steroid, used in the treatment of symptoms associated with menopause. Progestin is also a hormone. It is often used to control uterine bleeding that may be triggered by the presence of estrogens. A total of 36 women were treated for four weeks with a transdermal patch delivering 0.05 milligrams of estradiol daily. Sixteen then had one estradiol implant placed in the skin of the upper left arm. Twenty women had three of the implants placed. All women also received an intrauterine device (IUD) that released 20 micrograms daily of levonorgestrel, a progestin. Analysis of blood samples indicated that estradiol concentrations in women who had three implants were comparable to those achieved with the transdermal patch.

FLORIDA KEYS A recent Finland-to-Florida transplant, I had the Keys as a top to-do upon reaching U.S. soil. I wanted to go barefoot, drink in dive bars, see the six-toed [...]

Isocyanates are used in the manufacture of commercial products, including foams and adhesives. These chemicals may be toxic to various systems throughout the body, especially the lungs, but occasionally cause skin diseases as well. Fewer than 30 cases have been reported of isocyanates causing allergic contact dermatitis, the inflammation of the skin due to an allergy. Exposure to isocyanates can also cause irritant contact dermatitis, the inflammation and irritation of the skin due to contact with an irritant; thrombocytopenic purpura, a purplish discoloration of the skin associated with hemorrhage; urticaria, the development of itching wheals; and fever. Polyurethanes consist of polyols, which are thought to be skin sensitizers, and isocyanates. Welding of polyurethanes has reportedly caused fever. A case is described of a 40-year-old welder who developed urticaria and fever on four occasions when he was welding polyurethane-containing materials. The patient probably inhaled polyurethane fumes, which caused the development of urticaria. However, when the patient was re-exposed to two forms of isocyanate, he did not develop the skin reaction. This case shows the difficulty in identifying the cause of urticaria induced by airborne chemicals. (Consumer Summary produced by Reliance Medical Information, Inc.)

To evaluate the effect of hormonal contraception including combined oral contraceptives (COCs), and the injectable progestins depo-medroxyprogesterone acetate (DMPA) and norethisterone enanthate (Net-En) on the risk of HIV acquisition among women in South Africa.

We analyze the behavior of the parsec-scale jet of the quasar 3C 454.3 during pronounced flaring in 2005-2008. Three major disturbances propagated down the jet along different trajectories with Lorentz factors G > 10. The disturbances show a clear connection with millimeter-wave outbursts, in 2005 May/June, 2007 July, and 2007 December. High-amplitude optical events in the R-band light curve precede peaks of the millimeter-wave outbursts by 15-50 days. Each optical outburst is accompanied by an increase in X-ray activity. We associate the optical outbursts with propagation of the superluminal knots and derive the location of sites of energy dissipation in the form of radiation. The most prominent and long lasting of these, in 2005 May, occurred closer to the black hole, while the outbursts with a shorter duration in 2005 autumn and in 2007 might be connected with the passage of a disturbance through the millimeter-wave core of the jet. The optical outbursts, which coincide with the passage of superluminal radio knots through the core, are accompanied by systematic rotation of the position angle of optical linear polarization. Such rotation appears to be a common feature during the early stages of flares in blazars. We find correlations between optical variations and those at X-ray and g-ray energies. We conclude that the emergence of a superluminal knot from the core yields a series of optical and high-energy outbursts, and that the millimeter-wave core lies at the end of the jet's acceleration and collimation zone. We infer that the X-ray emission is produced via inverse Compton scattering by relativistic electrons of photons both from within the jet (synchrotron self-Compton) and external to the jet (external Compton, or EC); which one dominates depends on the physical parameters of the jet. A broken power-law model of the g-ray spectrum reflects a steepening of the synchrotron emission spectrum from near-IR to soft UV wavelengths. We propose that the g-ray emission is dominated by the EC mechanism, with the sheath of the jet supplying seed photons for g-ray events that occur near the millimeter-wave core.

We present the results of extensive multi-frequency monitoring of the radio galaxy 3C 120 between 2002 and 2007 at X-ray (2-10 keV), optical (R and V bands), and radio (14.5 and 37 GHz) wave bands, as well as imaging with the Very Long Baseline Array (VLBA) at 43 GHz. Over the 5 yr of observation, significant dips in the X-ray light curve are followed by ejections of bright superluminal knots in the VLBA images. Consistent with this, the X-ray flux and 37 GHz flux are anti-correlated with X-ray leading the radio variations. Furthermore, the total radiative output of a radio flare is related to the equivalent width of the corresponding X-ray dip. This implies that, in this radio galaxy, the radiative state of accretion disk plus corona system, where the X-rays are produced, has a direct effect on the events in the jet, where the radio emission originates. The X-ray power spectral density of 3C 120 shows a break, with steeper slope at shorter timescale and the break timescale is commensurate with the mass of the central black hole (BH) based on observations of Seyfert galaxies and black hole X-ray binaries (BHXRBs). These findings provide support for the paradigm that BHXRBs and both radio-loud and radio-quiet active galactic nuclei are fundamentally similar systems, with characteristic time and size scales linearly proportional to the mass of the central BH. The X-ray and optical variations are strongly correlated in 3C 120, which implies that the optical emission in this object arises from the same general region as the X-rays, i.e., in the accretion disk-corona system. We numerically model multi-wavelength light curves of 3C 120 from such a system with the optical-UV emission produced in the disk and the X-rays generated by scattering of thermal photons by hot electrons in the corona. From the comparison of the temporal properties of the model light curves to that of the observed variability, we constrain the physical size of the corona and the distances of the emitting regions from the central BH. In addition, we discuss physical scenarios for the disk-jet connection that are consistent with our observations.

Finnish Lapland emerged in 1809 when Sweden lost its eastern part of Lapland to Russia after the Finnish War. The area ceded was integrated into the Grand Duchy of Finland, an autonomous area in the Russian Empire. Finnish Lapland had about 39,700 inhabitants in the 1880s, of whom 960 (2%) were Sami. In 2003, the total population of the district of Lapland was 187,000, of whom 6000 (3%) were Sami. This paper deals with the transition periods in the Lappish economy over a long period. The transitions were associated with the border arrangements made in the 19th century on the one hand and the subsidies policy pursued by the government as well as more general socio-economic structural changes on the other. I will consider the economic transitions from the viewpoint of the current economic situation. Did the Lappish economy work better in the past, and in what conditions did it work on the whole?

We compare the Metsahovi 22 and 37 GHz total flux density variation data of active galactic nuclei with EGRET (on board the Compton Gamma Ray Observatory) gamma-ray observations from Cycles 1-4. Statistical analysis reveals that there is a genuine connection between the high-frequency radio properties of the sources, e.g., the type of the source, the phase of the radio flare, the associated radio variability brightness temperature, and the gamma-ray emission. Typically the most likely gamma-ray emitter is a high optical polarization quasar with a large Doppler boosting factor. The highest levels of gamma-ray emission are observed during the initial (or peak) stages of high-frequency radio flares. BL Lac objects are much weaker gamma-ray emitters, with no clear correlation between radio and gamma variations. We calculate the distance of the gamma-ray-emitting region from the core in quasars and obtain an average value of 4.9 pc, well downstream from the accretion disk or the broad-line region. This indicates that the strongest time-dependent gamma-ray emission of quasars originates in the relativistic jet, within the same shocks that produce the synchrotron flares at radio frequencies induced by the synchrotron self-Compton mechanism. Weaker gamma-ray emission does not seem to be associated with shocks and may be caused by other mechanisms, such as external Compton processes.

During the observation period 1997, the nearby blazar Mrk 501 showed extremely strong emission and high variability. We examine multiwavelength aspects of this event using radio, optical, soft and hard X-ray, and TeV data. We concentrate on the medium-timescale variability of the broadband spectra, averaged over weekly intervals. We confirm the previously found correlation between soft and hard X-ray emission and the emission at TeV energies, while the source shows only minor variability at radio and optical wavelengths. The nonlinear correlation between hard X-ray and TeV fluxes is consistent with a simple analytic estimate based on an SSC model in which Klein-Nishina effects are important for the highest-energy electrons in the jet, and flux variations are caused by variations of the electron density and/or the spectral index of the electron injection spectrum. The time-averaged spectra are fitted with a synchrotron self-Compton (SSC) dominated leptonic jet model, using the full Klein-Nishina cross section and following the self-consistent evolution of relativistic particles along the jet, accounting for ?? absorption and pair production within the source as well as due to the intergalactic infrared background radiation. The contribution from external inverse-Compton scattering is tightly constrained by the low maximum EGRET flux and found to be negligible at TeV energies. We find that high levels of the X-ray and TeV fluxes can be explained by a hardening of the energy spectra of electrons injected at the base of the jet, in remarkable contrast to the trend found for ?-ray flares of the flat-spectrum radio quasar PKS 0528+134.

We have calculated Doppler boosting factors, Dvar, for a sample of active galactic nuclei (AGNs) using total flux density variation monitoring data at 22 and 37 GHz. We argue that this method is more accurate than the other commonly used methods based on the synchrotron self-Compton X-ray flux or equipartition of energy. We compare our Doppler factors with other results and conclude that even if the average Dvar for a class of sources is very similar to all others, the variability Doppler factors for individual objects are more accurate and reliable. An important application of precise Doppler factors is presented, namely, calculating the Lorentz factors, G, and the viewing angles, th, of relativistic outflows inAGNs. We find that high-polarization quasars have the greatest Doppler boosting, while low-polarizationquasars and BL Lac objects are less boosted. The two groups of quasars show different characteristics because of different combinations of the Lorentz factor and viewing angle, rather than either a different G or th alone.

The presence of epidermal growth factor (EGF) and transforming growth factor-α (TGFα) immunoreactivities in fetal human tissues was studied immunohistochemically at different gestational ages. EGF and TGFαimmunoreactivities were detected from the 20th gestational wk. EGF immunoreactivity was limited to the small intestine, but TGFαimmunoreactive cells were present in the colon also. According to radioreceptor assay, the intestine of a 19-wk-old human fetus contained 10 times more EGF receptor-binding substance than EGF, as measured by immunofluorometric assay. Chromatographic analysis suggests that TGFα-like peptides account for at least part of this activity, as so argues in favor of the presence of TGFα- and EGF-like peptides in the human fetal gut. Whether they are synthesized in the fetus is yet unknown.

ABSTRACT: The presence of epidermal growth factor (EGF) and transforming growth factor-a (TGFa) immunoreactivities in fetal human tissues was studied immunohistochemically at different gestational ages. EGF and TGFaimmunoreactivities were detected from the 20th gestational wk. EGF immunoreactivity was limited to the small intestine, but TGFaimmunoreactive cells were present in the colon also. According to radioreceptor assay, the intestine of a 19-wk-old human fetus contained 10 times more EGF receptor-binding substance than EGF, as measured by immunofluorometric assay. Chromatographic analysis suggests that TGFa-like peptides account for at least part of this activity, as so argues in favor of the presence of TGFa- and EGF-like peptides in the human fetal gut. Whether they are synthesized in the fetus is yet unknown.

Peripheral plasma from four postmenopausal women was analysed for estrone, estradiol, luteinizing hormone and follicle stimulating hormone during 24 hours following an oral intake of a single dose of 1.0 mg micronized estradiol, on the first day of therapy and after one month. A similar study was carried out with another four postmenopausal patients, who received 0.2 mg estradiol three times daily. The measurements were performed by radioimmunoassay (RIA).It is concluded that the plasma concentrations of estrone and estradiol are higher and those of FSH lower after one month of therapy than on the first treatment day, while plasma LH remains unchanged. Micronized estradiol is rapidly absorbed from the gastrointestinal tract and converted to estrone, and the plasma profiles of estrone during the day are more constant with a divided daily dose than with a single higher dose. The divided daily dose results in an equally good clinical effect even though the total administration of estradiol is lower.

The return of fertility is rapid after first trimester abortion. The first ovulation may take place as soon as 2 weeks after abortion, and half of the women have ovulated by 3 weeks. Hence, commencement of effective contraception is necessary even before the first postabortal menstrual period. Women are highly motivated as regards contraception at this time. Several studies, both in developed and developing countries, have shown that the Insertion of a modern copper intrauterine device (IUD) at the end of the abortion procedure is a safe and well-accepted way to start the method. Hormonal methods, such as NORPLANT, levonorgestrel-releasing IUD, injectables and oral combination pills do not affect the recovery of the pituitary-ovarian system, even though introduced immediately after abortion. The combination of preceding pregnancy, abortion procedure and immediate start of low dose oral contraceptives containing 30 μg of ethinyloestradlol results in a slight tendency towards hypercoagulability. This may be clinically insignificant, but it can be avoided by postponing oral contraceptives until 1 week after abortion, without losing the contraceptive efficacy of the method.

Granulosa cells in developing follicles undergo changes in morphology and steroidogenesis during luteinization. Accordingly, the following questions arise: as granulosa cells secrete increased amounts of steroids during maturation, do their densities change, and might these alterations result in a heterogenous population of granulosa cells? To answer these questions, granulosa cells were separated by isopycnic gradient centrifugation on nonlinear and continuous 30% and 50% polyvinylpyrrolidone- coated silica gradients. 125I-human follicle-stimulating hormone (hFSH) labeled porcine granulosa cells and standardized density marker beads were used to generate a nomogram for conversion of the gradient elution volumes into densities. Separate pools of antral and mural granuiosa cells from large porcine follicles were dispersed in 0.02% EDTA-O.05% trypsin, then layered onto gradients and centrifuged at 800 × g (20 min, 20°C).Gradient aliquots were then cultured for 24 h in medium 199 supplemented with 15% fetal calf serum and antibiotics. Spent media were collected for progesterone determination, and the number of cells in each fraction quantitated by an automated cell counter. Mural cells displayed a uniform density of 1.02–1.03 g/ml, whereas antral cells displayed at least two distinct populations at 1.02–1.03 and 1.05–1.08 g/ml. Antral granulosa cells with higher density produced 7 times more progesterone (3.4 pg/cell per 24 h) than both mural and antral granulosa cells with lower density (0.5 pg/cell per 24 h). When aliquots of granulosa cells from medium sized follicles (3–5 mm) were cultured in the presence of pregnant mare’s serum gonadotropin (PMSG) for 0, 24, 48, and 72 h, a gradual shift in the density distribution was observed from the higher density towards the lower density cells, accompanied by a concomitant increase in both progesterone and estradiol secretion,In conclusion, by equilibrating granulosa cells to their specific gravity using isopycnic gradient centrifugation, we have found that the density of granulosa cells is a function, at least in part, of their steroidogenic capabilities. Further, their specific gravity changed as the cells luteinized in culture, accompanied by consequent changes in steroid secretion. That the developing follicle contains a heterogenous population of granulosa cells was evidenced by the marked difference in steroid secretory capacities of both mural and antra! granuiosa cells, and by their differential elution profiles following isopycnic centrifugation.

Two models of levonorgestrel-releasing intrauterine devices were studied. Model A was designed to deliver 20μg/day, and model B was designed to deliver 30μglday. Plasma concentrations of levonorgestrel were determined in blood samples taken from women who used the levonorgestrel-releasing intrauterine devices (IUDs) and who participated in a clinical trial for more than 5years. During clinical studies IUDs have been removed for various reasons between 8 and 40months after insertion. The rate of release of levonorgestrel from the IUDs was calculated by determining the remaining amount of levonorgestrel. Plasma concentrations of levonorgestrel ranged between a mean±standard deviation (SD) concentration of 166±75 pg/ml and131±32pg/ml for the first 18months of use and between 101±37 pg/ml and 74±15 pglml at 24 and 60months after insertion of the IUD. The plasma concentrations from 24months through 60months were significantly lower than concentrations measured during initial months of IUD use, but not between the two devices. There was a strong correlation between the time of use and the amount of levonorgestrel lost from the IUDs. The calculated mean daily release of levonorgestrel was 17.6μg for model A and 22.2μg for model B. This gives a calculated lifetime of more than 6years for a levonorgestrel-releasing IUD.

Copyright 1998 Academic Press Limited

The adhesiveness of 2 unencapsulated nonfimbriated strains of Haemophilus influenzae, 23459 and 23330, and the encapsulated fimbriated strain 770235 to extracellular matrix (ECM) and to its isolated components was studied, as was the potential of H. influenzae plasminogen receptors to enhance degradation of ECM and bacterial penetration through basement membrane. All strains exhibited efficient adhesiveness to reconstituted basement membrane and to ECM from cultured human endothelial cells. Strains 23459 and 23330 efficiently adhered to immobilized laminin, fibronectin, and various collagens. Strain 770235 adhered efficiently to fibronectin and type I and III collagens and with low efficiency to laminin. With all 3 strains, plasmin generated on H. injluenzae plasminogen receptors degraded laminin and fibronectin as well as ECM from human endothelial cells. Plasmin bound on H. influenzae cells also potentiated penetration of bacteria through a basement membrane preparation reconstituted on membrane filters. These results give evidence for a role of ECM adherence and plasminogen activation in the spread of H. injluenzae through tissue barriers.