Salinity stress is one of the more prevailing abiotic stresses which results in significant losses in agricultural crop production, particularly in arid and semi-arid areas ....
This review deals with the adaptive mechanisms that plants can implement to cope with the challenge of salt stress. Plants tolerant to NaCl implement a series of adaptations to acclimate to salinity, ...including morphological, physiological and biochemical changes. These changes include increases in the root/canopy ratio and in the chlorophyll content in addition to changes in the leaf anatomy that ultimately lead to preventing leaf ion toxicity, thus maintaining the water status in order to limit water loss and protect the photosynthesis process. Furthermore, we deal with the effect of salt stress on photosynthesis and chlorophyll fluorescence and some of the mechanisms thought to protect the photosynthetic machinery, including the xanthophyll cycle, photorespiration pathway, and water-water cycle. Finally, we also provide an updated discussion on salt-induced oxidative stress at the subcellular level and its effect on the antioxidant machinery in both salt-tolerant and salt-sensitive plants. The aim is to extend our understanding of how salinity may affect the physiological characteristics of plants.
Gram‐negative bacteria have mechanisms through which they can colonize and survive in different environments, such as the secretion systems types (1‐6) that have been widely studied and ...characterized. Nowadays, some authors have proposed extracellular structures, such as the outer membrane vesicles (OMVs), to be considered as an additional and independent secretion system. The OMVs are spherical particles of 50‐250 nm in diameter; they originate in the outer membrane, and therefore they have a very similar composition to the latter. These particles can transport an important variety of biomolecules: enzymes, toxins, antigenic determinants and even nucleic acids. Thus, it is of great interest to collect data describing the advantages of the transport of biomolecules through the OMVs and, thus, determine their role as a potential secretion system.
Membrane vesicle (MV) secretion is widely distributed in all domains of life. MVs carry nucleic acids, proteins or both. In this minireview Andrade‐Guerrero et al. revisit the state of the art MV secretion in bacteria, focusing in outer membrane vesicles (OMVs), and support the previously proposed idea of naming this as the type zero secretion system.
This study investigated the influence of inoculation with a plant growth-promoting rhizobacterium,
Pseudomonas mendocina Palleroni, alone or in combination with an arbuscular mycorrhizal (AM) fungus,
...Glomus intraradices (Schenk & Smith) or
Glomus mosseae (Nicol & Gerd.) Gerd. & Trappe, on antioxidant enzyme activities (catalase and total peroxidase), phosphatase activity, solute accumulation, growth and mineral nutrient uptake in leaves of
Lactuca sativa L. cv. Tafalla affected by three different levels of salt stress. Salinity decreased lettuce growth, regardless of the biological treatment and of the salt stress level. The plants inoculated with
P. mendocina had significantly greater shoot biomass than the control plants at both salinity levels, whereas the mycorrhizal inoculation treatments only were effective in increasing shoot biomass at the medium salinity level. At the highest salinity level, the water content was greater in leaves of plants treated with
P. mendocina or
G. mosseae. At the medium salinity level,
G. intraradices- or
G. mosseae-colonised plants showed the highest concentrations of foliar P. The
P. mendocina- and
G. mosseae-colonised plants presented higher concentrations of foliar K and lower concentrations of foliar Na under high salt conditions. Salt stress decreased sugar accumulation and increased foliar proline concentration, particularly in plants inoculated with the PGPR. Increasing salinity stress raised significantly the antioxidant enzyme activities, including those of total peroxidase and catalase, of lettuce leaves compared to their respective non-stressed controls. The PGPR strain induced a higher increase in these antioxidant enzymes in response to severe salinity. Inoculation with selected PGPR could serve as a useful tool for alleviating salinity stress in salt-sensitive plants.
The main objective of this systematic review is to synthesize the available evidence on the influence of parental styles and dimensions on the development of adolescents' externalizing behaviors. As ...a novelty, this review offers an analysis of possible differences in paternal and maternal parenting practices and the role of gender in adolescents will be analyzed. The methodology used consisted of a systematic search of articles in databases (Medline, Cochrane, Academic Search Premier, PsycINFO, ERIC y PsycARTICLES) and their lists of bibliographic references published between 2010 and 2016. Initially, we located 31,169 studies, of which 31,019 were excluded because they were either duplicates or did not meet the inclusion and exclusion criteria. The remaining articles were again reviewed in full text and were subjected to the assessment of bias risk, of which 17 had an adequate level of methodological quality, and so were included in the systematic review. The results suggest that the parenting style most closely associated with externalizing problems is the authoritarian style. In contrast, the authoritative parental style and the dimensions of affection, communication, and autonomy promotion guarantee positive results. A larger number of studies are deemed necessary to establish firm conclusions about aspects such as differences between parents' parenting style or adolescents' gender.
Electrophoretic deposition of chitosan-bioactive glass (45S5 composition) composite coatings on magnesium alloy (WE43) substrates was investigated. Two types of substrates were considered, one was ...the bare, non-pre-treated substrate, while the other one had been treated in Dulbecco’s Modified Eagle Medium (DMEM). The protective effect of the coatings (of ∼2μm in thickness) against corrosion was tested using electrochemical impedance spectroscopy and the coatings’ bioactive behaviour was determined in simulated body fluid. A tribo-mechanical characterization of the coatings was performed. Overall, results confirmed the importance of pre-treating the substrate to corrosion protective chitosan-bioactive glass coatings on WE43 alloy.
Salt stress is one of the most damaging abiotic stresses because most crop plants are susceptible to salinity to different degrees. According to the FAO, about 800 million Has of land are affected by ...salinity worldwide. Unfortunately, this situation will worsen in the context of climate change, where there will be an overall increase in temperature and a decrease in average annual rainfall worldwide.
This Special Issue presents different research works and reviews on the response of plants to salinity, focused from different points of view: physiological, biochemical, and molecular levels. Although an important part of the studies on the response to salinity have been carried out with Arabidopsis plants, the use of other species with agronomic interest is also notable, including woody plants.
Most of the conducted studies in this Special Issue were focused on the identification and characterization of candidate genes for salt tolerance in higher plants. This identification would provide valuable information about the molecular and genetic mechanisms involved in the salt tolerance response, and it also supplies important resources to breeding programs for salt tolerance in plants.
In the vehicular ad hoc networks (VANETs), due to the high mobility of vehicles, the network parameters change frequently and the information that the sender maintains may outdate when it wants to ...transmit data packet to the receiver, so for improving the routing efficiency and reliability, we propose the probability prediction-based reliable and efficient opportunistic routing (PRO) algorithm for VANETs. The PRO routing algorithm can predict the variation of signal-to-interference-plus-noise ratio (SINR) and packet queue length (PQL) of the receiver. The prediction results are used to determine the utility of each relaying vehicle in the candidate set. The calculation of the vehicle's utility is the weight-based algorithm, and the weights are the variances of SINR and PQL. The relaying priority of each relaying vehicle is determined by the value of its utility. By these innovations, the PRO can achieve better routing performance (such as the packet delivery ratio, the end-to-end delay, and the network throughput) than the SRPE, ExOR (street-centric), and greedy perimeter stateless routing algorithms.
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