Bioremediation, involving bioaugmentation and/or biostimulation, being an economical and eco-friendly approach, has emerged as the most advantageous soil and water clean-up technique for contaminated ...sites containing heavy metals and/or organic pollutants. Addition of pre-grown microbial cultures to enhance the degradation of unwanted compounds (bioaugmentation) and/or injection of nutrients and other supplementary components to the native microbial population to induce propagation at a hastened rate (biostimulation), are the most common approaches for in situ bioremediation of accidental spills and chronically contaminated sites worldwide. However, many factors like strain selection, microbial ecology, type of contaminant, environmental constraints, as well as procedures of culture introduction, may lead to their failure. These drawbacks, along with fragmented literature, have opened a gap between laboratory trials and on-field application. The present review discusses the effectiveness as well as the limitations of bioaugmentation and biostimulation processes. A summary of experimental studies both in confined systems under controlled conditions and of real case studies in the field is presented. A comparative account between the two techniques and also the current scenario worldwide for in situ biotreatment using bioaugmentation and biostimulation, are addressed.
Berries contain significant amounts of phytochemicals, including polyphenols, which are reported to reduce cancer risk, coronary heart disease and other degenerative diseases. These effects are ...mainly attributed to the antioxidant capacity of polyphenols found in berries. Strawberry tree (Arbutus unedo) berries are used in folk medicine but seldom eaten as fresh fruits. Their phenolic profile and antioxidant capacity reveal a high potential, but they are not well characterized as a "health promoting food". The aim of this study was to assess the antioxidant properties of the edible strawberry tree fruit in vitro and in a neurodegeneration cell model. Raspberry (Rubus idaeus), a well documented health-promoting fruit, was used as a control for comparison purposes. A. unedo yielded a similar content in polyphenols and a slightly lower value of total antioxidant capacity in comparison to R. idaeus. Although the chemically-measured antioxidant activity was similar between both fruits, R. idaeus increased neuroblastoma survival in a neurodegeneration cell model by 36.6% whereas A. unedo extracts caused no effect on neuroblastoma viability. These results clearly demonstrate that a promising level of chemically-determined antioxidant activity of a plant extract is not necessarily correlated with biological significance, as assessed by the effect of A. unedo fruit in a neurodegeneration cell model.
The use of many traditional medicinal plants is often hampered by the absence of a proper biochemical characterization, essential to identify the bioactive compounds present. The leaves from five ...species endemic to the Macaronesian islands with recognized ethnobotanical applications were analysed: Apollonias barbujana (Cav.) Bornm., Ocotea foetens (Ainton) Baill, Prunus azorica (Mouill.) Rivas-Mart., Lousã, Fern. Prieto, E. Días, J.C. Costa & C. Aguiar, Rumex maderensis Lowe and Plantago arborescens Poir. subsp. maderensis (Dcne.) A. Hans. et Kunk.. Since oxidative stress is a common feature of most diseases traditionally treated by these plants, it is important to assess their antioxidant capacity and determine the molecules responsible for this capacity. In this study, the antioxidant capacity of these plants against two of the most important reactive species in human body (hydroxyl and peroxyl radicals) was determined. To trace the antioxidant origin total phenol and flavonoid contents as well as the polyphenolic profile and the amount of trace elements were determined. There was a wide variation among the species analysed in what concerns their total leaf phenol and flavonoid contents. From the High Performance Liquid Chromatography (HPLC) electrochemically detected peaks it was possible to attribute to flavonoids the antioxidant capacity detected in A. barbujana, O. foetens, R. maderensis and P. azorica extracts. These potential reactive flavonoids were identified for A. barbujana, R. maderensis and P. azorica. For R. maderensis a high content (7 mg g-1 dry weight) of L-ascorbic acid, an already described antioxidant phytomolecule, was found. A high content in selenomethionine (414.35 microg g-1 dry weight) was obtained for P. arborescens subsp. maderensis extract. This selenocompound is already described as a hydroxyl radical scavenger is reported in this work as also possessing peroxyl radical scavenging capacity. This work is a good illustration of different phytomolecules (flavonoids, organic acids and selenocompounds), presents in leaves of the five traditional medicinal plants endemic to Macaronesia, all exhibiting antioxidant properties.
Context: Natural products are reported to have substantial neuroprotective activity due to their radical scavenging capacity, and also acetylcholinesterase (AChE) inhibitory capacity, both activities ...important in neurodegeneration.
Objective: The undesirable side effects of compounds in pharmacological use make it important to identify natural neuroprotective molecules. This work assesses the potential of five endemic Portuguese plants as sources of neuroprotective compounds.
Materials and methods: Antioxidant capacity for peroxyl radical was determined by Oxygen Radical Absorbance Capacity method and for hydroxyl by Electron Paramagnetic Resonance, as well as AChE inhibitory capacity of the plant hydroethanolic extracts. The molecules responsible for these valuable properties were also tentatively identified by HPLC.
Results and discussion: Armeria rouyana and Thymus capitellatus presented some of the highest phenolic contents (76.60 ± 7.19 and 12.82 ± 0.24 mg GAE g−1 dw, respectively) and antioxidant capacities (592 ± 116 and 449 ± 57 μmol TE g−1 dw, respectively). The flavonoids were identified as the phytomolecules related to the antioxidant capacity of these plant extracts; in the case of A. rouyana, l-ascorbic acid also made an important contribution (3.27 ± 0.26 mg g−1 dw). Plant extracts clearly demonstrated effective AChE inhibitory activity (480 ± 98 and 490 ± 46 μg mL−1, respectively), that could be associated to polyphenols.
Conclusions: The extracts of A. rouyana and T. capitellatus and their active components, especially polyphenols, demonstrate interesting neuroprotective potential. They, therefore, deserve further study as their phytomolecules are promising sources of either natural neuroprotective products and/or novel lead compounds.
In this work, we propose a real-time traffic scheduler framework that is generalized to handle both voice and video in the downlink of Orthogonal Frequency Division Multiple Access (OFDMA) based ...cellular networks like 3GPP Long Term Evolution (LTE). These networks are packet switched in nature. As a result, Packet Scheduling (PS) and Radio Resource Allocation (RRA) algorithms at the Base Station (BS) play an important role in achieving high capacity. The paper, thus, proposes a new RRA algorithm which combines time domain PS and frequency domain RRA, thereby increasing the system capacity of both VoIP and video users. The algorithm is also seen to improve the percentage user satisfaction while keeping the radio resource utilization nearly unchanged. Its performance is analyzed using LTE system parameters and evaluated according to ITU-R specified methodologies. Results of key performance indicators such as system capacity, scheduling delay, Physical Resource Block (PRB) utilization, percentage user satisfaction are shown.
Important developmental processes in both plants and animals are partly regulated by genes whose expression is modulated at the post-transcriptional level by processes such as RNA interference ...(RNAi). Dicers, Argonautes and RNA-dependent RNA polymerases (RDR) form the core components that facilitate gene silencing and have been implicated in the initiation and maintenance of the trigger RNA molecules, central to process of RNAi. Investigations in eukaryotes have revealed that these proteins are encoded by variable number of genes with plants showing relatively higher number in each gene family. To date, no systematic expression profiling of these genes in any of the organisms has been reported.
In this study, we provide a complete analysis of rice Dicer-like, Argonaute and RDR gene families including gene structure, genomic localization and phylogenetic relatedness among gene family members. We also present microarray-based expression profiling of these genes during 14 stages of reproductive and 5 stages of vegetative development and in response to cold, salt and dehydration stress. We have identified 8 Dicer-like (OsDCLs), 19 Argonaute (OsAGOs) and 5 RNA-dependent RNA polymerase (OsRDRs) genes in rice. Based on phylogeny, each of these genes families have been categorized into four subgroups. Although most of the genes express both in vegetative and reproductive organs, 2 OsDCLs, 14 OsAGOs and 3 OsRDRs were found to express specifically/preferentially during stages of reproductive development. Of these, 2 OsAGOs exhibited preferential up-regulation in seeds. One of the Argonautes (OsAGO2) also showed specific up-regulation in response to cold, salt and dehydration stress.
This investigation has identified 23 rice genes belonging to DCL, Argonaute and RDR gene families that could potentially be involved in reproductive development-specific gene regulatory mechanisms. These data provide an insight into probable domains of activity of these genes and a basis for further, more detailed investigations aimed at understanding the contribution of individual components of RNA silencing machinery during reproductive phase of plant development.
The objective of the study is preparation of shape memory blend of polycarbonate (PC) and thermoplastic polyurethane (TPU). Polycarbonate is blended with three types of TPUs and subsequently ...mechanical, thermal, morphological, and shape memory properties of the PC/TPU blends are studied. When TPU content in the blend is higher than 40% (by weight), the glass transition temperature related to PC is not shown in the differential scanning calorimetry thermogram, indicating loss of PC properties. The 60/40 optimized blend of PC/TPUs exhibits maximum increment of about 1100% in elongation and 43% decrement in tensile strength. The shape recovery of the optimized blend obtained by addition of 40% (by weight) of TPUs in PC polymer is found to be 65% and shape fixity is 97%. These results suggest that the blend of PC/TPU may be utilized for various applications where shape memory property is required including strategic applications.
The addition of different grades of thermoplastic polyurethane (TPUs) in polycarbonate (PC) was carried out to improve elongation of PC. differential scanning calorimetry thermograms have revealed that upto 40% TPUs addition, glass transition temperature of PC is maintained, beyond which PC changes its characteristic.
eIF4A is a DEAD box containing RNA helicase that plays crucial roles in regulating translation initiation, growth and abiotic stress tolerance in plants. It also functions as an ATP-dependent RNA ...binding protein to curb granule formation by limiting RNA-RNA interactions that promote RNA condensation and formation of ribonucleoprotein particles in vivo. Helicase activity of eIF4A is known to be dictated by its binding partners. Proteins interacting with eIF4A have been identified across land plants. In monocots a close link between eIF4A regulated processes and DNA methylation in epigenetic regulation of plant development is inferred from interaction between OseIF4A and the de novo methyltransferase OsDRM2 and loss-of-function studies of these genes in Oryza sativa and Brachypodium distachyon. In the moss Physcomitrella patens, eIF4A1 encoded by Pp3c6_1080V3.1 interacts with the heterogeneous nuclear ribonucleoprotein (hnRNP) PpLIF2L1, homolog of which in Arabidopsis regulates transcription of stress-responsive genes. In this study, using different protein-protein interaction methods, targeted gene knockout strategy and quantitative expression analysis we show genetic interaction between PpeIF4A1 and the putative nucleosome remodeler protein PpDDM1 and between PpDDM1 and PpLIF2L1 in vivo. Stress-induced co-expression of PpeIF4A1, PpDDM1 and PpLIF2L1, their roles in salt stress tolerance and differences in subnuclear distribution of PpLIF2L1 in ppeif4a1 cells in comparison to wild type suggest existence of a regulatory network comprising of RNA helicases, chromatin remodelling proteins and hnRNP active in stress-responsive biological processes in P. patens.
•In moss RNA helicase eIF4A1 and DDM1 interact and are essential for stress recovery.•Genetic interaction between PpeIF4A1 and hnRNP LIF2L1 may regulate speckle formation.•PpeIF4A1, PpDDM1 and PpLIF2L1 regulated activities may be linked in stress response.
UV coatings for wooden surfaces Rawat, Rajkumar Singh; Chouhan, Nidhi; Talwar, Meenu ...
Progress in organic coatings,
October 2019, 2019-10-00, 20191001, Letnik:
135
Journal Article
Recenzirano
•The objective of the study was fulfilled by developing a sprayable and fast curing coating composition.•Fast curing UV coating composition (10 s curing time) having flow time of 114 s was designed ...for application on wooden surfaces. The commercial UV coating has curing time of 30 s and flow time 49 s.•The developed UV coating exhibits superior thermal stability then commercial UV & conventional coatings as evident from TGA.•The UV coating was found to be superior in respect to surface resistance than conventional coatings
Ultra violet (UV) radiation curing has emerged as a fast and environment friendly curing technique for coating on various surfaces (wood, metals, plastic & stone). Although, there are several UV curable coating formulations available in the international market, but these coatings have quite low viscosity and are not suitable for wooden surfaces as coatings tend to quickly get absorbed in to the porous structure of wood leading to slow curing. There is a need for designing coating formulations which are although sprayable, but have optimum viscosity so as to not get absorbed into the wooden surfaces. Besides, coatings have to have fast curing rate as well, so that while in process of curing they do not get absorbed in to the wood. Generally, UV curable coatings comprise of acrylate based oligomers (epoxy, polyurethane, and polyester), reactive diluents (mono-, di-, or polyfunctional glycidyl ether), photoinitiator (benzyl peroxide, phosphine oxide) and functional additives. These coating compositions are first applied on wooden surface and then exposed to UV radiation for curing. The photoinitiator dissociates on UV exposure to form free radicals, which initiate the polymerization of the oligomers and diluents, leading to the formation of a polymeric crosslinked network on the wooden surface. In the present study, sprayable coating compositions were designed based on epoxy acrylate that get cured within 10 s of UV exposure and exhibit excellent thermal and stain resistance properties.
eIF4A is a RNA-stimulated ATPase and helicase. Besides its key role in regulating cap-dependent translation initiation in eukaryotes, it also performs specific functions in regulating cell cycle ...progression, plant growth and abiotic stress tolerance. Flowering plants encode three eIF4A paralogues,
eIF4A1
,
eIF4A2
and
eIF4A3
that share conserved sequence motifs but differ in functions. To date, however, no information is available on eIF4A in basal land plants. In this study we report that genome of the moss
Physcomitrella patens
encodes multiple eIF4A genes. The encoded proteins possess the highly conserved motifs characteristic of the DEAD box helicases. Spatial expression analysis shows these genes to be ubiquitously expressed in all tissue types with
Pp3c6_1080V3.1
showing high expression in filamentous protonemata. Targeted deletion of conserved core motifs in
Pp3c6_1080V3.1
slowed protonemata growth and resulted in dwarfing of leafy gametophores suggesting a role for
Pp3c6_1080V3.1
in regulating cell division/elongation. Rapid and strong induction of
Pp3c6_1080V3.1
under salt stress and slow recovery of knockout plants upon exposure to high salt further suggest
Pp3c6_1080V3.1
to be involved in stress management in
P. patens
. Protein–protein interaction studies that show Pp3c6_1080V3.1 to interact with the Physcomitrella heterogenous ribonucleoprotein, LIF2L1, a transcriptional regulator of stress-responsive genes in Arabidopsis. The results presented in this study provide insight into evolutionary conserved functions of eIF4A and shed light on the novel link between eIF4A activities and stress mitigation pathways/RNA metabolic processes in
P. patens
.
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