432 research outputs found
The structure of sets with few sums along a graph
AbstractWe present common generalizations of some structure results of Freiman, Ruzsa, Balog–Szemerédi and Laczkovich–Ruzsa. We also give some applications to Combinatorial Geometry and Algebra, some of which generalize the aforementioned structure results even further
Identification of protein kinase inhibitors with a selective negative effect on the viability of Epstein-Barr virus infected B cell lines
Epstein-Barr virus (EBV) is a human herpesvirus, which is causally associated with the development of several B lymphocytic malignancies that include Burkitt's lymphomas, Hodgkin's disease, AIDS and posttransplant associated lymphomas. The transforming activity of EBV is orchestrated by several latent viral proteins that mimic and modulate cellular growth promoting and antiapoptotic signaling pathways, which involve among others the activity of protein kinases. In an effort to identify small molecule inhibitors of the growth of EBV-transformed B lymphocytes a library of 254 kinase inhibitors was screened. This effort identified two tyrosine kinase inhibitors and two MEK inhibitors that compromised preferentially the viability of EBV-infected human B lymphocytes. Our findings highlight the possible dependence of EBV-infected B lymphocytes on specific kinase-regulated pathways underlining the potential for the development of small molecule-based therapeutics that could target selectively EBV-associated human B lymphocyte malignancies. © 2014 Mavromatidis et al
The relationship between the big five personality dimensions and acute psychopathology: mediating and moderating effects of coping strategies.
BACKGROUND: Prior research suggests that the Big Five personality dimensions might be associated with coping strategies as well as acute psychopathology. The aim of the present study was to investigate direct and indirect associations between the Big Five personality traits, coping styles, and psychopathological variables. SUBJECTS AND METHODS: Subjects were 1140 adults from various institutions and regions in Hungary. A comprehensive test battery was administered including the Big Five Inventory (BFI), Psychological Immune System Inventory (PISI), and some subscales of the Brief Symptom Inventory (BSI). Several moderation-mediation analyses were conducted using the PROCESS tool in SPSS to test for influence paths. RESULTS: Coping and personality variables jointly accounted for 40% to 50% of variance in psychopathology outcome. Personality dimensions of Extraversion, Conscientiousness and Emotional Stability had strongest predictive values. Emotional Stability had a more direct and unmediated effect, whereas Extraversion and Conscientiousness effects were mediated by the Approach and Self-regulation coping systems. In comparison to personality, coping style was generally a stronger predictor. CONCLUSIONS: The findings of this study might add to better understanding of complex pathways leading from broad personality dimensions to coping strategies and psychological (mal)adjustment
Magnetic hysteresis in Ising-like dipole-dipole model
Using zero temperature Monte Carlo simulations we have studied the magnetic
hysteresis in a three-dimensional Ising model with nearest neighbor exchange
and dipolar interaction. The average magnetization of spins located inside a
sphere on a cubic lattice is determined as a function of magnetic field varied
periodically. The simulations have justified the appearance of hysteresis and
allowed us to have a deeper insight into the series of metastable states
developed during this process.Comment: REVTEX, 10 pages including 4 figure
Crossover of texture and morphology in (Ti1 − xAlx)1 − yYyN alloy films and the pathway of structure evolution
In our earlier published work, we have shown that there is a composition range of the (Ti 1 − x Al x ) 1 − y Y y N alloy
films (0.72 b Ti/Al b 0.88) deposited at oblique vapour beam incidence and 500 °C (corresponding to zone T) in
which mixed cubic TiN (c-TiN) and wurtzite AlN (w-AlN) structures were formed together with an unusual
complex texture. The texture of c-TiN phase changed from 〈001〉 to b111N at a certain thickness forming a definite
crossover. Moreover the c-TiNb111N and the w-AlN〈0001〉 crystals were epitaxially related with axes tilted to the
direction of the vapour beam.
Based on a comprehensive transmission electron microscopy (TEM) and diffraction (XRD and selected area
electron diffraction (SAED)) structure and morphology analysis, we discovered the details of this exotic structure
making it possible to construct the complex pathway of structure evolution including the formation of the w-AlN
phase and the change of the dominating texture of c-TiN phase with thickness in dependence of the Ti/Al ratio
and the deposition parameters. This pathway could be deduced from the fundamental phenomena of structure
formation and may be generalised for multi-component thin film systems. A composition structure zone
model has been also proposed for the (Ti 1 − x Al x ) 1 − y Y y N thin film system in the 0 b x b 1 composition range
Crossover of texture and morphology in (Ti 1 − x Al x ) 1 − y Y y N alloy films and the pathway of structure evolution
In our earlier published work, we have shown that there is a composition range of the (Ti 1 − x Al x ) 1 − y Y y N alloy
films (0.72 b Ti/Al b 0.88) deposited at oblique vapour beam incidence and 500 °C (corresponding to zone T) in
which mixed cubic TiN (c-TiN) and wurtzite AlN (w-AlN) structures were formed together with an unusual
complex texture. The texture of c-TiN phase changed from 〈001〉 to b111N at a certain thickness forming a definite
crossover. Moreover the c-TiNb111N and the w-AlN〈0001〉 crystals were epitaxially related with axes tilted to the
direction of the vapour beam.
Based on a comprehensive transmission electron microscopy (TEM) and diffraction (XRD and selected area
electron diffraction (SAED)) structure and morphology analysis, we discovered the details of this exotic structure
making it possible to construct the complex pathway of structure evolution including the formation of the w-AlN
phase and the change of the dominating texture of c-TiN phase with thickness in dependence of the Ti/Al ratio
and the deposition parameters. This pathway could be deduced from the fundamental phenomena of structure
formation and may be generalised for multi-component thin film systems. A composition structure zone
model has been also proposed for the (Ti 1 − x Al x ) 1 − y Y y N thin film system in the 0 b x b 1 composition range
Metilviologén (paraquat) toleráns nyárfaklónok (Populus x canescens) szelekciója és alkalmazása fitoremediációban
Paraquat (syn.: metilviologén) toleráns nyárfa (Populus x canescens) klónok
szelekcióját végeztük el in vitro kultúrában. A szintetikus talaj összetétele: WPM
(Woody Plant Media) tápsók, 1% szacharóz, 0,8 % agar 1 mg/l benziladenin, 0,2 mg/l
naftilecetsav és paraquat koncentráció sor (2×10(-6) M, 1,47×10(-6) M, 9,3×10(-7) M, 4×10(-7)
M) volt. A regeneránsokat szelekciós táptalajon történő tesztelés után felszaporítottuk
(mikroszaporítás), gyökeresítettük, majd üvegházban felneveltük. A molekuláris (RTqPCR)
és biokémiai elemzések (aszkorbát peroxidáz, glutation peroxidáz, glutation Stranszferáz,
lipoxigenáz) igazolták egy rendkívül stabil paraquat toleráns klón sikeres
szelekcióját. A klónokat az in vitro vizsgálatokat követően in situ (Fűzfőgyártelep)
teszteljük gyomirtószer maradványok toleranciájára. | Paraquat (syn.: methylviologen) tolerant poplar (P. x canescens) clones (PQT) were
selected in in vitro cultures at concentration series of paraquat (2×10(-6) M, 1.47×10(-6) M,
9.3×10(-7) M, 4×10(-7) M). After testing on tissue culture media, regenerants were
micropropagated. After rooting, PQT-clones were transplanted to a greenhouse. PQT
clones showed significantly higher gst gene expression then wild type (WT) analyzed
by RT-qPCR (quantitative reverse transcriptase PCR). For functional analysis enzyme
activities of GST (glutathione S-transferase), APOX (ascorbate peroxides), GR
(glutathione reductase), and LOX (lipoxygenase, pH 8.0) were determined. After
rooting, PQT-clones were transplanted in glass houses, followed by field performance
analyses for phytoremediation (environmental clean up using plants) capacity in heavily
contaminated area at Balatonfűzfő, Hungar
A gst gén DNS-demetilált overexpressziója a szürkenyár (Populus x canescens) fitoremediációs kapacitásának növelésére
A szürkenyár (Populus x canescens) gst (glutation S-transzferáz) génexpresszióját
növeltük meg DHAC-indukált (5,6-dihidro-5'-azacitidin hidroklorid) DNSdemetilációval.
Három klónt vizsgáltunk, a természetes (WT) és két glutationtúltermelő
35S-gshI nyárfaklónt (11ggs, 6lgl) RT-qPCR elemzésben. A gst gén
megemelt expressziós szintje a DHAC-kezelt kontroll növényekben 4,9-szeresre
emelkedett, amely tovább nőtt paraquat stresszben (11,2-szeres), amely eredmény azt
bizonyítja, hogy a DNS demetilációjával az endogén gének expressziós szintje
nagyságrendekkel emelhető meg. Ismert, hogy a DNS demetiláció a vegetativ
klónokban öröklődik (epigenetikus memória), ezért a demetilációs eljárás (gén upreguláció)
új lehetőséget ad stressztűrő nyárfaklónok előállítására. | In the study presented gst (glutathione S-transferase) gene expression levels of
poplar (Populus x canescens) were analyzed in response to the DNA demethylating
agent DHAC (5,6-dihydro-5'-azacytidine hydrochloride). Aseptic leaf discs cultures of
wild type (WT) and two gshI-transgenic clones (6lgl and 11ggs) clones were analyzed
by RT-qPCR. High expression levels of DHAC treated control plants (4.9-fold
increment, and a further 11.2-fold increment after paraquat treatment) proves that DNA
demethylation provides powerful tools in gene-upregulation. As DNA methylation
patterns are inherited (‘epigenetic memory’) novel poplar plant sources are provided
with increased gst gene expression levels
- …