Hydrogels are materials with wide applications in several fields, including the biomedical and pharmaceutical industries. Their properties such as the capacity of absorbing great amounts of aqueous ...solutions without losing shape and mechanical properties, as well as loading drugs of different nature, including hydrophobic ones and biomolecules, give an idea of their versatility and promising demand. As they have been explored in a great number of studies for years, many routes of synthesis have been developed, especially for chemical/permanent hydrogels. In the same way, stimuli-responsive hydrogels, also known as intelligent materials, have been explored too, enhancing the regulation of properties such as targeting and drug release. By controlling the particle size, hydrogel on the micro- and nanoscale have been studied likewise and have increased, even more, the possibilities for applications of the so-called XXI century materials. In this paper, we aimed to produce an overview of the recent studies concerning methods of synthesis, biomedical, and pharmaceutical applications of macro-, micro, and nanogels.
Nowadays, the majority of the photovoltaic (PV) power sources are connected to the public grid. One of the main connection problems occurs when voltage sags appear in the grid due to short circuits, ...lightning, etc. International standards regulate the grid connection of PV systems, forcing the source to remain connected during short-time grid-voltage faults. As a consequence, during the voltage sag, the source should operate with increasing converter currents to maintain the injection of the generated power. This abnormal operation may result in nondesired system disconnections due to overcurrents. This paper proposes a controller for a PV three-phase inverter that ensures minimum peak values in the grid-injected currents, as compared with conventional controllers. From the system analysis, a design method is presented in order to set the parameters of the control scheme. Selected experimental results are reported in order to validate the effectiveness of the proposed control.
Thioamides are important biophysical probes of peptide folding but are prone to α-C epimerization during Fmoc solid-phase peptide synthesis. The stereochemical integrity of thioamide-containing ...peptides can be dramatically improved by protecting the thioamide as a thioimidate during synthesis. A drawback of this approach, however, is that once synthesis of the peptide is complete, regeneration of the thioamide requires the toxic, corrosive, and flammable gas H2S. This work examines several approaches to supplant H2S as a deprotection reagent in favor of a safer and more convenient alternative. Ultimately, a new application of the 4-azidobenzyl protecting group to thioamides was found to provide the most suitable means of both protection of α-C stereochemistry and conversion back to thioamide.
For rivers and streams, the impact of rising water temperature on biochemical oxygen demand (BOD) assimilative capacity depends on the interplay of two independent factors: the waterbody’s dissolved ...oxygen (DO) saturation and its self-purification rate (i.e., the balance between BOD oxidation and reaeration). Although both processes increase with rising water temperatures, oxygen depletion due to BOD oxidation increases faster than reaeration. The net result is that rising temperatures will decrease the ability of the world’s natural waters to assimilate oxygen-demanding wastes beyond the damage due to reduced saturation alone. This effect should be worse for nitrogenous BOD than for carbonaceous BOD because of the former’s higher sensitivity to rising water temperatures. Focusing on streams and rivers, the classic Streeter–Phelps model was used to determine the magnitude of the maximum or “critical” DO deficit that can be calculated analytically as a function of the mixing-point BOD concentration, DO saturation, and the self-purification rate. The results indicate that high-velocity streams will be the most sensitive to rising temperatures. This is significant because such systems typically occur in mountainous regions where they are also subject to lower oxygen saturation due to decreased oxygen partial pressure. Further, they are dominated by salmonids and other cold-water fish that require higher oxygen levels than warm-water species. Due to their high reaeration rates, such systems typically exhibit high self-purification constants and consequently have higher assimilation capacities than slower moving lowland rivers. For slow-moving rivers, the total sustainable mixing-point concentration for CBOD is primarily dictated by saturation reductions. For faster flowing streams, the sensitivity of the total sustainable load is more equally dependent on temperature-induced reductions in both saturation and self-purification.
The molecular machinery for protein synthesis is profoundly similar between plants and other eukaryotes. Mechanisms of translational gene regulation are embedded into the broader network of RNA-level ...processes including RNA quality control and RNA turnover. However, over eons of their separate history, plants acquired new components, dropped others, and generally evolved an alternate way of making the parts list of protein synthesis work. Research over the past 5 years has unveiled how plants utilize translational control to defend themselves against viruses, regulate translation in response to metabolites, and reversibly adjust translation to a wide variety of environmental parameters. Moreover, during seed and pollen development plants make use of RNA granules and other translational controls to underpin developmental transitions between quiescent and metabolically active stages. The economics of resource allocation over the daily light-dark cycle also include controls over cellular protein synthesis. Important new insights into translational control on cytosolic ribosomes continue to emerge from studies of translational control mechanisms in viruses. Finally, sketches of coherent signaling pathways that connect external stimuli with a translational response are emerging, anchored in part around TOR and GCN2 kinase signaling networks. These again reveal some mechanisms that are familiar and others that are different from other eukaryotes, motivating deeper studies on translational control in plants. This article is categorized under: Translation > Translation Regulation RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
Highlights • OMV and OMV-NP were safe in mice. • One single dose of OMVs either free or loaded into nanoparticles was able to protect mice from an experimental infection. • Nanoencapsulation of the ...OMVs extract allowed a reduction in the antigen dose administered. • Both OMVs and OMV-NP induced protection by the oral route at the different doses evaluated. • The demonstration of cross-protective immunity using this OMV-vaccine will determine the nearby future of this approach.
Kaempferol is a natural flavonoid widely found in fruits, vegetables, and tea. Kaempferol possesses beneficial biological properties such as anti-inflammatory and antioxidant activities. Positive ...energy balance during obesity correlates with a pro-inflammatory chronic state. In this context, we hypothesized that kaempferol might promote anti-obesity effects by modulating adipogenesis and lipolytic pathways. Adipocyte viability at 24, 48, and 72 h was measured by an ATP-based assay. Pre-adipocytes (day 0) or mature adipocytes (day 12) were treated with 60 μM kaempferol until day 21 to evaluate its potential anti-adipogenic and lipolytic effect, respectively. Total lipid accumulation was assessed using Oil Red O staining assay. Gene expression was measured by RT-qPCR to evaluate the effect of kaempferol on adipogenesis and lipolysis gene expression. Our results showed a dose-dependent effect of kaempferol treatment on cell viability promoting cell death at higher than 60 μM concentration. Pre-adipocytes stimulation by 60 μM kaempferol resulted in 62% adipogenesis inhibition whereas in mature adipocytes, it reduced 39% intracellular lipid accumulation. Also, 60 μM kaempferol treatment decreased
Cebpa
mRNA expression when compared to control cells. In contrast,
Pnpla2
and
Lipe
gene expression were upregulated in 3T3-L1 cells incubated with 60 μM kaempferol. In summary, our results showed that kaempferol modulates adipogenic differentiation in 3T3-L1 cells by promoting downregulation of
Cebpa
gene expression and decreasing lipid accumulation in mature adipocytes by its positive effects on
Pnpla2
and
Lipe
mRNA levels. Kaempferol might display an anti-obesity effect.
Background
Allergen immunotherapy is a treatment modality which can be applied using different vaccines. The aim of this study was to quantify and compare the allergen content of different house dust ...mites (HDM)’ sublingual treatments and to review the evidence on their efficacy.
Methods
Five sublingual allergen immunotherapy (SLIT) products were ordered and purchased at an ordinary pharmacy and masked for blinding before the study was started. Detection of Dermatophagoides pteronyssinus and Dermatophagoides farinae allergens Der p 1, Der f 1, Der p 2 and Der f 2 was carried out by immunoblotting and fluorescent multiplex. A literature search for meta‐analyses and systematic reviews that included SLIT‐HDM products was performed.
Results
Der p 1 concentrations ranged from 0.6 to 14.5 μg/ml; similar figures were found for Der f 1 that ranged from 0.2 to 12.4 μg/ml. Der p 2+ Der f 2 ranged from 0.2 to 1.5 μg/ml. Data on efficacy are scarce for most of the five products.
Conclusions
Substantial variations regarding allergen content were found among these five SLIT‐HDM products. Therefore, it can be necessary to guarantee the quality of the SLIT‐HDM products and to demonstrate their effectiveness before they are marketed. It seems necessary, for the moment, to take into account these characteristics of the products before prescribing.
Plastics pollution has become one of the greatest concerns of the 21st century. To date, around 10 billion tons of plastics have been produced almost exclusively from non‐renewable sources, and of ...these, <10% have been recycled. The majority of discarded plastic waste (>70%) is accumulating in landfills or the environment, causing severe impacts to natural ecosystems and human health. Considering how plastics are present in every aspect of our daily lives, it is evident that a transition towards a Circular Economy of plastics is essential to achieve several of the Sustainable Development Goals. In this editorial, we highlight how microbial biotechnology can contribute to this shift, with a special focus on the biological recycling of conventional plastics and the upcycling of plastic‐waste feedstocks into new value‐added products. Although important hurdles will need to be overcome in this endeavour, recent success stories highlight how interdisciplinary approaches can bring us closer to a bio‐based economy for the sustainable management of plastics.
This paper employs Economic Input-Output Life Cycle Assessment and Data Envelopment Analysis to attribute total (direct and indirect) hazardous waste generation to the different industries and to ...connect total hazardous waste generation to the value added generated by each industry in Spain. In difference with previous studies we include all the industries of the economy and we focus on one specific type of environmental burden: the generation of hazardous waste. The results show that there is a very high concentration in total hazardous waste generation: only three industries accounted for almost 80% of total hazardous waste generation. This concentration also affects the type of hazardous waste generated. Thus, we find two main types of waste that account for 93% of total hazardous waste. Overall, the greatest hazardous waste generating industries are also the least efficient ones and exhibit a high improvement potential. Prevention measures directed to these industries should be implemented.
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•Total hazardous waste generation in Spain in 2016 is estimated.•Only three industries account for 80% of total hazardous waste generation.•Two types of hazardous waste represent 93% of total hazardous waste generation.•Improvement potential in higher in leading hazardous waste generating industries•Prevention measures should be directed to the industries identified.
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