376 research outputs found
Association study of suicidal behavior and affective disorders with a genetic polymorphism in ABCG1, a positional candidate on chromosome 21q22.3
The gene that codes for the ABC transporter ABCG1 is located in a chromosomal susceptibility region (21q22.3) for affective disorders. Genetic variations in ABCG1 have been associated with affective disorders in Japanese males. In this study, we investigated the distribution of a G2457A polymorphism in patients with affective disorders, suicide attempters with various psychiatric diagnoses and healthy subjects, We initially found a trend towards a modest association with affective disorders in males (p = 0.046 for allele frequencies and p = 0.046 for AA versus GG). We conducted a replication study with independent patients and controls, There was no association with affective disorders, either in the replication or in the combined group, Furthermore, we found no association with suicidal behavior, These findings do not support the hypothesis that ABCG1 is a susceptibility gene for affective disorders or suicidal behavior. Copyright (C) 2000 S. Karger AG, Basel
(α,n) reaction cross section measurement on 92,94Mo isotopes
The cross section of the 92,94Mo(α,n)95,97Ru reactions were measured recently at MTA Atomki using the activation method and thick targets to study the origin of the proton-rich nuclei heavier than iron. The experimental details of the
cross section measurement are presented in this paper
Experimental determination of the He(,)Be reaction cross section above the Be proton separation threshold
The He(,)Be reaction plays a major role both in the
BBN producing the majority of the primordial Li, and in the pp-chain, where
it is the branching point. As a few-nucleon system, this reaction is often used
to validate ab-initio theoretical calculations and/or test R-matrix theory and
code implementations. For the latter, experimental data in an extended energy
range is of crucial importance to test the fit and extrapolation capabilities
of the different codes. The He(,)Be reaction cross
section has been measured by several groups up to the first resonance
( MeV) in the reaction. However, only one dataset exists
above the Be proton separation threshold measured in a narrow energy range
( MeV). In this work we extend the available experimental
capture cross section database to the energy range of known Be levels. The
activation method was used. The experiment was performed using a thin-window
gas cell with two high-purity Al foils as entrance and exit windows. The
activity of the Be nuclei implanted in the exit/catcher foil was measured
by detecting the yield of the emitted ~rays using shielded high-purity
germanium detectors. New experimental He(,)Be reaction
cross section data were obtained for the first time in the
MeV energy region. The new dataset with about 0.2 MeV step covers the energy
range of known levels and particle separation thresholds. No prominent
structures are observer around the Be levels. The reaction cross section is
slowly increasing with increasing energy. Above the Li threshold, a
decrease starts in the cross section trend. The overall structure of the cross
section suggest a broad resonance peaking around MeV Be
excitation energy, with a width of 8 MeV.Comment: Accepted for publication in PR
New method for preparation of delivery systems of poorly soluble drugs on the basis of functionalized mesoporous MCM-41 nanoparticles
MCM-41 silica with spherical morphology and small particle sizes (100 nm) was synthesized and modified by post-synthesis method with amino and/or carboxylic groups. Solid state reaction was applied for the first time for loading of poorly soluble drug mesalazine (5-aminosalicylic acid – 5-ASA). Thenon-loaded and drug loaded mesoporous silicas were characterized by XRD, TEM, N2 physisorption, elemental analysis, thermal analysis, FT-IR and solid state NMR spectroscopy. Quantum-chemical calculations were used to predict the interactions between the drug molecule and the functional groups of the carrier. The nanoparticles were post-coated with sodium alginate and the coating modified the rate of mesalazine release from MCM-41NH2 and MCM-41NH2COOH particles. Cytotoxic evaluation on colon adenocarcinoma cell line revealed that the alginate coating reduced cytotoxicity of mesalazine loaded in the post-coated particles compared to the pure mesalazine. The functionalized, polymer coated mesoporous systems are suitable oral drug delivery systems providing an opportunity to modify drug release
Exploring the circumstellar environment of the young eruptive star V2492 Cyg
Context. V2492 Cyg is a young eruptive star that went into outburst in 2010.
The near-infrared color changes observed since the outburst peak suggest that
the source belongs to a newly defined sub-class of young eruptive stars, where
time-dependent accretion and variable line-of-sight extinction play a combined
role in the flux changes.
Aims. In order to learn about the origin of the light variations and to
explore the circumstellar and interstellar environment of V2492 Cyg, we
monitored the source at ten different wavelengths, between 0.55 \mu m and 2.2
\mu m from the ground and between 3.6 \mu m and 160 \mu m from space.
Methods. We analyze the light curves and study the color-color diagrams via
comparison with the standard reddening path. We examine the structure of the
molecular cloud hosting V2492 Cyg by computing temperature and optical depth
maps from the far-infrared data.
Results. We find that the shapes of the light curves at different wavelengths
are strictly self-similar and that the observed variability is related to a
single physical process, most likely variable extinction. We suggest that the
central source is episodically occulted by a dense dust cloud in the inner
disk, and, based on the invariability of the far-infrared fluxes, we propose
that it is a long-lived rather than a transient structure. In some respects,
V2492 Cyg can be regarded as a young, embedded analog of UX Orionis-type stars.
Conclusions. The example of V2492 Cyg demonstrates that the light variations
of young eruptive stars are not exclusively related to changing accretion. The
variability provided information on an azimuthally asymmetric structural
element in the inner disk. Such an asymmetric density distribution in the
terrestrial zone may also have consequences for the initial conditions of
planet formation.Comment: 9 pages, 7 figures, 2 online tables, accepted for publication in A&
Enhancing ultrafiltration performance for dairy wastewater treatment using a 3D printed turbulence promoter
Dairy factories annually generate an increasing amount of wastewater, which can cause eutrophication due to high concentrations of amino acids and lipids. To address this issue, membrane technology has emerged as a promising solution, but membrane fouling remains a significant challenge, since it can cause decreased flux, decrease membrane rejection performance, and increased energy demand. This study aimed to reduce membrane fouling by integrated a three-dimensional printed (3DP) turbulence promoter into an ultrafiltration dead-end cell and varying stirring speeds. Two mathematical models, Hermia and resistance-in-series, were used to analyze the fouling process. According to both models, the cake layer formation model indicated the most prevalent fouling mechanism. Specific energy demand, permeate flux, membrane rejection, and membrane reversible and irreversible resistances were measured, calculated, and compared. The results suggest that the combination of an integrated 3DP turbulence promoter and high stirring speeds can effectively reduce membrane fouling in a dairy wastewater treatment module
- …