A
bstract
Based on an integrated luminosity of 1.61 fb
−
1
e
+
e
−
collision data collected with the KLOE detector at DAΦNE, the Frascati
ϕ
-factory, a search for the
P
- and
CP
-violating decay
η → ...π
+
π
−
has been performed. Radiative
ϕ → ηγ
decay is exploited to access the
η
mesons. No signal is observed in the
π
+
π
−
invariant mass spectrum, and the upper limit on the branching fraction at 90% confidence level is determined to be ℬ(
η → π
+
π
−
)
<
4
.
9
×
10
−
6
, which is approximately three times smaller than the previous KLOE result. From the combination of these two measurements we get ℬ(
η → π
+
π
−
)
<
4
.
4
×
10
−
6
at 90% confidence level.
The reconstitution of the integral membrane protein photosynthetic reaction center (RC) in polymersomes, i.e. artificial closed vesicles, was achieved by the micelle-to-vesicle transition technique, ...a very mild protocol based on size exclusion chromatography often used to drive the incorporation of proteins contemporarily to liposome formation. An optimized protocol was used to successfully reconstitute the protein in a fully active state in polymersomes formed by the tri-block copolymers PMOXA22-PDMS61-PMOXA22. The RC is very sensitive to its solubilizing environment and was used to probe the positioning of the protein in the vesicles. According to charge-recombination experiments and to the enzymatic activity assay, the RC is found to accommodate in the PMOXA22 region of the polymersome, facing the water bulk solution, rather than in the PDMS61 transmembrane-like region. Furthermore, polymersomes were found to preserve protein integrity efficiently as the biomimetic lipid bilayers but show a much longer temporal stability than lipid based vesicles.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The possibility to synthesize heavier superheavy elements in massive nuclei reactions is strongly limited by the hindrance to complete fusion of reacting nuclei: due to the onset of the quasifission ...process in the entrance channel, which competes with complete fusion, and by strong increase of the fission yield along the de-excitation cascade of the compound nucleus in comparison to the evaporation residue formation. We present a wide and detailed procedure allowing us to describe the experimental results (evaporation residue nuclei and fissionlike products) in the mass asymmetric and symmetric reactions. Very reliable estimations and perspectives for the synthesis of superheavy elements in many massive nuclei reactions up to Z = 120 and eventually also for Z > 120 have been obtained.
The BGO Calorimeter of BGO-OD Experiment Bantes, B; Bayadilov, D; Beck, R ...
Journal of physics. Conference series,
01/2015, Volume:
587, Issue:
1
Journal Article
Peer reviewed
Open access
The BGO Rugby Ball is a large solid angle electromagnetic calorimeter now installed in the ELSA Facility in Bonn. The BGO is operating in the BGO-OD experiment aiming to study meson photoproduction ...off proton and neutron induced by a Bremsstrahlung polarized gamma beam of energies from 0.2 to 3.2 GeV and an intensity of 5 × 107 photons per second. The scintillating material characteristics and the photomultiplier read-out make this detector particularly suited for the detection of medium energy photons and electrons with very good energy resolution. The detector has been equipped with a new electronics read-out system, consisting of 30 sampling ADC Wie-Ne-R modules which perform the off-line reconstruction of the signal start-time allowing for a good timing resolution. Performances in linearity, resolution and time response have been carefully tested at the Beam Test Facility of the INFN National Laboratories in Frascati by using a matrix of 7 BGO crystals coupled to photomultipliers and equipped with the Wie-Ne-R sampling ADCs.
In recent years, several new oral contraceptives have become available. In some ways, they represent an evolution in terms of individualization and compliance on the part of women. The new ...formulations make it increasingly possible to prescribe a specific hormonal contraceptive on an individual basis.
A systematic literature search of PubMed was performed using the following combination of terms: 'oral contraceptives', 'estroprogestins' and 'combined oral contraceptive'. Only English-language papers published between January 2000 and July 2014 were included in our analysis. The present review analyzes all aspects of the choice of oral contraceptives in the different phases of a woman's life in detail.
Regarding the estrogen component, lowering the dose of ethinylestradiol (EE) helped reduce associated side effects. Natural estradiol is now available and represents a valid alternative to EE. And regarding progestins, the dose has changed over time, as well as the endocrine and metabolic characteristics. These are the fruit of much research into improvement of old products (19-nor-progesterone-derived progestins) with androgenic effects and testing of new molecules with improved metabolic neutrality in terms of insulin sensitivity and lipid parameters. New progestins were a genuine turning point because they greatly reduced major side effects, such as water retention, and their anti-androgenic properties made them indicated for all forms of hyperandrogenism associated with acne and mild hirsutism. The associations of estradiol/dienogest and estradiol/nomegestrol acetate are the most suitable contraceptives for women with abundant menstrual bleeding and can increase the number of potential users of hormonal contraception.
Progress in the provision of new oral contraceptives has improved the risk/benefit ratio, by increasing benefits and reducing risks. The present challenge is to tailor contraceptives to individual needs in terms of efficacy and protection of reproductive health.
The effects of physiological changes in estrogens and androgens on the erythrocyte antioxidant superoxide dismutase, catalase and glutathione peroxidase enzyme activities during the menstrual cycle ...were investigated in healthy eumenorrheic women. Blood samples were taken on alternate days from twelve normally cyclic women (age range: 20 to 27 years; mean age: 24.1 years) from the first day of one menstrual cycle until the first day of the subsequent one. Plasma was analyzed for FSH, LH, estradiol, progesterone, testosterone, free testosterone and androstenedione concentrations. Erythrocyte superoxide dismutase, catalase and glutathione peroxidase activities were evaluated on the same days and cycle length was standardized on the basis of the preovulatory estradiol peak. Significant cyclic phase-related changes were observed in glutathione peroxidase (P<0.05), with higher glutathione peroxidase activity levels from the late follicular to the early luteal phase compared with those found in the early follicular phase (P<0.001 and P<0.002 respectively). A significant positive correlation was observed between mean estradiol and glutathione peroxidase cycle-related variations (r=0.80, P<0.001), whereas no significant cycle phase-dependent changes were seen in superoxide dismutase and catalase. No effect of progesterone and androgens on the erythrocyte antioxidant enzyme system was documented. The findings indicate that physiological ovarian estradiol production during the menstrual cycle may have an important role in regulating erythrocyte glutathione peroxidase activity.
We present the analysis of K− absorption processes on He4 leading to Λπ− final states, measured with the KLOE spectrometer at the DAΦNE e+e− collider and extract, for the first time, the modulus of ...the non-resonant K−n →Λπ− direct production amplitude about 33 MeV below the K‾N threshold. This analysis also allows to disentangle the K− nuclear absorption at-rest from the in-flight capture, for K− momenta of about 120 MeV. The data are interpreted with the help of a phenomenological model, and the modulus of the non-resonant K−n →Λπ− amplitude for K− absorption at-rest is found to be |AK−n→Λπ−|=(0.334±0.018stat−0.058+0.034syst)fm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We study the effect of the static characteristics of nuclei and dynamics of the nucleus-nucleus interaction in the capture stage of reaction, in the competition between quasifission and complete ...fusion processes, as well as the angular momentum dependence of the competition between fission and evaporation processes along the de-excitation cascade of the compound nucleus. The results calculated for the mass-asymmetric and less mass-asymmetric reactions in the entrance channel are analyzed in order to investigate the role of the dynamical effects on the yields of the evaporation residue nuclei. We also discuss about uncertainties at the extraction of such relevant physical quantities as Γn/Γtot ratio or also excitation functions from the experimental results due to the not always realistic assumptions in the treatment and analysis of the detected events. This procedure can lead to large ambiguity when the complete fusion process is strongly hindered or when the fast fission contribution is large. We emphasize that a refined multiparameter model of the reaction dynamics as well as a more detailed and checked data analysis are strongly needed in heavy-ion collisions.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The $\Sigma$ beam asymmetry in $\eta^{\prime}$ photoproduction off the proton was measured at the GrAAL polarized photon beam with incoming photon energies of 1.461 and 1.480 GeV. For both energies ...the asymmetry as a function of the meson emission angle shows a clear structure, more pronounced at the lowest one, with a change of sign around 90$^o$. The results are compared to the existing theories that fail to account for the data.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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