817 research outputs found
Influence of Malolactic Fermentation on the Quality of Riesling Wine
Biotic and abiotic stress has a negative effect on both the quality and quantity of grape production. Like many woody crops, grape has been relatively recalcitrant to in vitro manipulations. The crucial point in the process of genetic transformation is to have cells that are able to both regenerate and be transformed. A regeneration system seems to be a major problem in the transformation process. Somatic embryogenesis is the favoured regenerative protocol in genetic transformations of grapes. Comparison of an embryogenic and organogenic system in grape demonstrated that organogenesis frequently leads to chemical transformation of tissues. In this respect we started to develop and apply procedures suitable for the genetic transformation of grapevine. Two sources of explants were used for embryo induction. In the first case, immature zygotic ovules of Vitis vinifera seedless genotypes were used. In the second case in vivo leaf tissues from rootstocks Vitis rupestris cv. Rupestris du Lot and 110 Richter (Vitis berlandieri x Vitis rupestris). Continual transfer to fresh medium maintained embryogenic cultures. Agrobacterium tumefaciens mediated transformation of enbryogenic cultures of seedless grapes (Vitis vinifera L.) with constructs containing the gene encoding the coat protein of Grape Fanleaf Virus (GFLV) and with four constructs containing genes encoding for an antifreeze protein. An embryogenic culture of rootstock Vitis rupestris cv. Rupestris du Lot was transformed with a construct carrying the bete-glucoronidase (GUS) gene. The first transformed plantlets have been regenerated from somatic embryos and the presence of the NPTII gene was verified by PCR and Southern blot analyses
Bipolar querying of valid-time intervals subject to uncertainty
Databases model parts of reality by containing data representing properties of real-world objects or concepts. Often, some of these properties are time-related. Thus, databases often contain data representing time-related information. However, as they may be produced by humans, such data or information may contain imperfections like uncertainties. An important purpose of databases is to allow their data to be queried, to allow access to the information these data represent. Users may do this using queries, in which they describe their preferences concerning the data they are (not) interested in. Because users may have both positive and negative such preferences, they may want to query databases in a bipolar way. Such preferences may also have a temporal nature, but, traditionally, temporal query conditions are handled specifically. In this paper, a novel technique is presented to query a valid-time relation containing uncertain valid-time data in a bipolar way, which allows the query to have a single bipolar temporal query condition
More supplements to a class of logarithmically completely monotonic functions associated with the gamma function
In this article, a necessary and sufficient condition and a necessary
condition are established for a function involving the gamma function to be
logarithmically completely monotonic on . As applications of the
necessary and sufficient condition, some inequalities for bounding the psi and
polygamma functions and the ratio of two gamma functions are derived.Comment: 8 page
Increased power generation in supercapacitive microbial fuel cell stack using Fe-N-C cathode catalyst
The anode and cathode electrodes of a microbial fuel cell (MFC) stack, composed of 28 single MFCs, were used as
the negative and positive electrodes, respectively of an internal self-charged supercapacitor. Particularly, carbon
veil was used as the negative electrode and activated carbon with a Fe-based catalyst as the positive electrode.
The red-ox reactions on the anode and cathode, self-charged these electrodes creating an internal electrochemical
double layer capacitor. Galvanostatic discharges were performed at different current and time pulses.
Supercapacitive-MFC (SC-MFC) was also tested at four different solution conductivities. SC-MFC had an
equivalent series resistance (ESR) decreasing from 6.00 Ω to 3.42 Ω in four solutions with conductivity between
2.5 mScmâ1 and 40 mScmâ1. The ohmic resistance of the positive electrode corresponded to 75â80% of the
overall ESR. The highest performance was achieved with a solution conductivity of 40 mS cmâ1 and this was due
to the positive electrode potential enhancement for the utilization of Fe-based catalysts. Maximum power was
36.9mW (36.9Wmâ3) that decreased with increasing pulse time. SC-MFC was subjected to 4520 cycles (8 days)
with a pulse time of 5 s (ipulse 55 mA) and a self-recharging time of 150 s showing robust reproducibility
The First 1 1/2 Years of TOTEM Roman Pot Operation at LHC
Since the LHC running season 2010, the TOTEM Roman Pots (RPs) are fully
operational and serve for collecting elastic and diffractive proton-proton
scattering data. Like for other moveable devices approaching the high intensity
LHC beams, a reliable and precise control of the RP position is critical to
machine protection. After a review of the RP movement control and position
interlock system, the crucial task of alignment will be discussed.Comment: 3 pages, 6 figures; 2nd International Particle Accelerator Conference
(IPAC 2011), San Sebastian, Spain; contribution MOPO01
Tissue-specific modulation of gene expression in response to lowered insulin signalling in Drosophila
Reduced activity of the insulin/IGF signalling network increases health during ageing in multiple species. Diverse and tissue-specific mechanisms drive the health improvement. Here, we performed tissue-specific transcriptional and proteomic profiling of long-lived Drosophila dilp2-3,5 mutants, and identified tissue-specific regulation of >3600 transcripts and >3700 proteins. Most expression changes were regulated post-transcriptionally in the fat body, and only in mutants infected with the endosymbiotic bacteria, Wolbachia pipientis, which increases their lifespan. Bioinformatic analysis identified reduced co-translational ER targeting of secreted and membrane-associated proteins and increased DNA damage/repair response proteins. Accordingly, age-related DNA damage and genome instability were lower in fat body of the mutant, and overexpression of a minichromosome maintenance protein subunit extended lifespan. Proteins involved in carbohydrate metabolism showed altered expression in the mutant intestine, and gut-specific overexpression of a lysosomal mannosidase increased autophagy, gut homeostasis, and lifespan. These processes are candidates for combatting ageing-related decline in other organisms
Deregulated splicing is a major mechanism of RNA-induced toxicity in Huntington's disease
Huntington's disease (HD) is caused by an expanded CAG repeat in the huntingtin (HTT) gene, translating into an elongated polyglutamine stretch. In addition to the neurotoxic mutant HTT protein, the mutant CAG repeat RNA can exert toxic functions by trapping RNA-binding proteins. While few examples of proteins that aberrantly bind to mutant HTT RNA and execute abnormal function in conjunction with the CAG repeat RNA have been described, an unbiased approach to identify the interactome of mutant HTT RNA is missing. Here, we describe the analysis of proteins that preferentially bind mutant HTT RNA using a mass spectrometry approach. We show that (I) the majority of proteins captured by mutant HTT RNA belong to the spliceosome pathway, (II) expression of mutant CAG repeat RNA induces mis-splicing in a HD cell model, (III) overexpression of one of the splice factors trapped by mutant HTT ameliorates the HD phenotype in a fly model and (VI) deregulated splicing occurs in human HD brain. Our data suggest that deregulated splicing is a prominent mechanism of RNA-induced toxicity in HD
PHOTOELECTROCHEMICAL CHOLESTEROL BIOSENSING VIA P(SNS-NH 2 )/CHOX/[RU(BPY) 3 ] 2+ MODIFIED ELECTRODES
ABSTRACT Despite the numerous studies on photochemically induced electron transfer in proteins 1 , there is no precedence for the photonic wiring of redox enzymes with electrodes and their bioelectrocatalytic activation. The use of enzymes in fuel-generating solar cells has been discussed previously 2 . The electrical wiring of the enzymes in these systems was achieved, however, by applying natural cofactors (nicotinamide adenine dinucleotide (phosphate)) and their regeneration by photochemical means 3 . Also, the field of enzyme-based biofuel cells has been substantially advanced in the past decade, and numerous organic materials, such as alcohols, sugars, or ahydroxy acids, have been used as fuels for the biocatalyzed generation of electrical power in the presence of oxyge
LHC Optics Measurement with Proton Tracks Detected by the Roman Pots of the TOTEM Experiment
Precise knowledge of the beam optics at the LHC is crucial to fulfil the
physics goals of the TOTEM experiment, where the kinematics of the scattered
protons is reconstructed with the near-beam telescopes -- so-called Roman Pots
(RP). Before being detected, the protons' trajectories are influenced by the
magnetic fields of the accelerator lattice. Thus precise understanding of the
proton transport is of key importance for the experiment. A novel method of
optics evaluation is proposed which exploits kinematical distributions of
elastically scattered protons observed in the RPs. Theoretical predictions, as
well as Monte Carlo studies, show that the residual uncertainty of this optics
estimation method is smaller than 0.25 percent.Comment: 20 pages, 11 figures, 5 figures, to be submitted to New J. Phy
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