1,614 research outputs found
The Technical Evolution of CA Storage Protocols and the Advancements in Elucidating the Fruit Responses to Low Oxygen Stress
Abstract
Innovations in postharvest technology also deal with the modulation of gas
composition in storage rooms and/or packaging, in particular concerning oxygen
levels, which, for some storage protocols and fruit crops, is set at extremely low
concentrations (less than 1 kPa). Since the establishment of the first commercial CA rooms,
the oxygen concentration showed a constant decrease throughout decades, reaching
the lowest levels used in ULO (Ultra Low Oxygen), ILOS (Initial Low Oxygen
Stress), and DCA (Dynamic Controlled Atmosphere) applications. This decreasing
trend in oxygen concentrations used in storage rooms resulted in a general
improvement of the quality parameters and the marketable life of the commodities
(apples, in particular). The optimization of these techniques and the reduction of the
risks (development of physiological disorders, off-odors, off-flavors) associated with
keeping the fruit at such extreme conditions need to be based on a better knowledge
of the metabolic responses to hypoxia. The metabolic responses of fruit tissues to
low-oxygen stress are, as observed in model plants, mainly related to dramatic
changes in mitochondrial respiration and the activation of the fermentative
metabolism that appear to be differently affected (resulting in different levels of
ethanol accumulation) by different low oxygen levels and in relation to the genetic
background. Among others, ethanol, alanine, asparagine and aspartate
concentrations in cortex tissue markedly change in relation to hypoxic conditions,
thus representing possible metabolic markers of this kind of stress. Specific volatile
compounds of apples are also differentially affected, whereas other volatile classes
appear more stable. Using large-scale transcriptomic approaches coupled with
metabolic profiling analyses it is now possible to better describe the global fruit
responses to low oxygen conditions. In apples, in addition to the expression of genes
involved in primary metabolism (major CHO, fermentation), hypoxia also affects
specific secondary metabolic pathways that appear to be selectively modulated by
different low oxygen treatments. Members of the ERF-VII transcription factors
(TFs) gene family displayed differential expression suggesting their involvement in
the modulation or controlling mechanisms of hypoxic responses, as observed in
model species
Modelling and Measurement of Charge Transfer in Multiple GEM Structures
Measurements and numerical simulations on the charge transfer in Gas Electron
Multiplier (GEM) foils are presented and their implications for the usage of
GEM foils in Time Projection Chambers are discussed. A small test chamber has
been constructed and operated with up to three GEM foils. The charge transfer
parameters derived from the electrical currents monitored during the
irradiation with an Fe-55 source are compared with numerical simulations. The
performance in magnetic fields up to 2 T is also investigated.Comment: 21 pages, 16 figures, submitted to NIM-
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Reducing crop losses by gene-editing control of organ developmental physiology
Some physiological processes in reproductive organs, if not controlled, can lead to crop loss even in the absence of environmental stress. These processes may occur pre- or post- harvest, and in diverse species and include abscission processes in cereal grain, e.g., shattering and in immature fruit, e.g., preharvest drop, preharvest sprouting of cereals, and postharvest senescence in fruit. Some of the molecular mechanisms and genetic determinants underlying these processes are now better detailed, making it possible to refine them by gene editing. Here, we discuss using advanced genomics to identify genetic determinants underlying crop physiological traits. Examples of improved phenotypes developed for preharvest problems are provided, and suggestions for reducing postharvest fruit losses by gene and promoter editing were made
Intellectual property as complex innovation projects component
The materials presented the possibilities development of intellectual property complex innovation projects modern highly effective science-based problems of improving the use of wastes of different industries on a complex enterprise that can provide all its energy needs alone. Some features of the possibilities of solving evidence-based problems of development of mechanisms for identifying syner-gistic processes, their scientific justification improving the use of wastes of different industries on a complex enterprise. The problem of wastes utilization and recycling is present as complex synergetic processes research and analysis of energy- and resource saving process-es for treatment of polymer wastes of various origin. The research focused on the study of issues such as the development of models of waste-modifying polymer. The investigation are focused in researching such problems as selection of scientific based methods of wastes to be utilized or recycled; the development of appropriated process flow sheets and choice of modifications additives and equipment for polymers waste recycling. The choice of appropriate plants with selected energy resources is very important for projects realization
Charge Transfer and Charge Broadening of GEM Structures in High Magnetic Fields
We report on measurements of charge transfer in GEM structures in high
magnetic fields. These were performed in the framework of the R&D work for a
Time Projection Chamber at a future Linear Collider. A small test chamber has
been installed into the aperture of a superconducting magnet with the GEM
structures mounted perpendicular to the B field direction. The charge transfer
is derived from the electrical currents monitored during irradiation with an
Fe source. No severe loss of primary ionisation charge is observed,
but an improved ion feedback suppression is achieved for high magnetic fields.
Additionally, the width of the charge cloud released by individual Fe
photons is measured using a finely segmented strip readout after the triple GEM
structure. Charge widths between 0.3 and 0.5 mm RMS are observed, which
originate from the charge broadening inside the GEM readout. This charge
broadening is only partly suppressed at high magnetic fields.Comment: 11 pages, 9 figure
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