关键词： Redox flow battery   Carbon nanotubes   Grid energy storage   Alternative energy  

摘要： Rapid resource consumption and shifting public perspective on traditional electricity sources has forced the development of renewable energy sources, such as wind and solar energy. Redox flow batteries have become an important research area due to their independent power density and energy density, which is unique for electro-chemical energy conversion and storage devices. These batteries are designed for grid-scale energy storage to be paired with wind and solar energy to create power grids that are not dependent on fossil fuels. The DOE has issued a 2023 target of 150 $/KWh and current all-vanadium chemistries approach these levels solely in vanadium costs. Therefore, other chemistries need to be developed that have long term stability, affordability, high performance, and utilize the high conductivity of water. Electrode doping facilitates charge transfer reactions at the electrode/electrolyte interface by improving the wettability and activity of the electrode to permit higher power and energy systems. These developments and inventive chemistries provide opportunities to employ cheaper chemistries to help meet the future demand for renewable energy. The recent developments in aqueous redox flow batteries utilizing chemistries other than vanadium are discussed in this review.

关键词： Leukoreduction filter   Buffy coat   Dendritic cell   Biological resource  

摘要： Dendritic cells are one of the most popular immune cells, which plays a remarkable role in both immunotherapy and tolerance induction. Due to unwanted side effects of leukocyte presence in donated blood, the policy of blood service is the pre-storage reduction of leukocytes, which today, filtration is the most common method for this purpose. The filtration method has led to diminished access to Buffy coat as a generally used conventional source of biological cells. We developed a simple, affordable, and reproducible method for dendritic cell differentiation from filter-derived monocytes and, the results of the filter study were compared with differentiated DCs from the conventional buffy coat-derived monocytes. The Monocytes were recovered from leukoreduction filter using an optimized protocol with supplemented PBS buffer. Following the adhesion method, CD14(+) Monocyte-enriched population with the purity of 94 % was obtained. After cytokine stimulation over a 6-day period and maturation induction by LPS, differentiated DCs were evaluated for morphology, surface markers (CD86, CD40, CD83 and, HLA-DR), antigen uptake potency and IL-12 secretion. Analysis and comparison of the results represented no significant difference between the two groups. Accordingly, we conclude that leukoreduction filters could be introduced as a reliable and research-grade source of monocyte for DC generation in biological research.

摘要： Background: Amikacin, meropenem, minocycline, and fosfomycin have potential clinical utility for orthopaedic infections;however, their suitability for use in polymethylmethacrylate (PMMA) is poorly understood. The purpose of this study was (1) to quantify the thermal stability of these antibiotics at clinically relevant temperatures and (2) to determine the elution pharmacodynamics of these alternative antibiotics in vitro from PMMA beads of different sizes. Methods: Polymerization temperatures of 10-mm PMMA beads were measured over time to generate a simulated heating curve. Aqueous solutions of tobramycin, amikacin, meropenem, minocycline, and fosfomycin were subjected to the temperature curves, followed by incubation at 37 degrees C. Minimum inhibitory concentrations of each antibiotic were evaluated against Staphylococcus aureus, Escherichia coli, and Acinetobacter baumannii. High-dose 4.5-mm, 6-mm, and 10-mm antibiotic-laden PMMA beads (10% antibiotic by weight) were submerged individually in a phosphate-buffered saline solution and incubated at 37 degrees C. Antibiotic elution was determined with use of high-performance liquid chromatography with mass spectrometry. Results: Tobramycin, amikacin, and fosfomycin demonstrated thermal stability and maintained antimicrobial activity for 28 days. Minocycline and meropenem lost antimicrobial activity against all 3 organisms after 48 hours and 7 days, respectively. Elution concentrations, rates, and cumulative drug mass for tobramycin, amikacin, and meropenem were orders of magnitude higher than minocycline and fosfomycin at each time point. Conclusions: This study identified notable differences in thermal stability and elution among antibiotics used to treat infections. Amikacin exhibited activity similarly to tobramycin. Meropenem demonstrated favorable elution kinetics and thermal stability in the initial 7-day period.

关键词： Life cycle assessment   Mining   Environmental impacts   Iron   Fluorspar  

摘要： Mining represents the first step to the access to mineral resources. The impacts induced by such operations now contribute to the impacts of a wide range of goods and services, given the widespread use of these raw materials in the worldwide economy. In this context, this study aims at assessing the environmental performance of mining operations in a life cycle perspective, considering two currently operating mine sites: the Erzberg iron open-pit mine (Austria) and the Lujar fluorspar underground mine (Spain). In particular, this study aims at i) identifying the main environmental hotspots along the cradle-to-gate exploitation of mineral deposits in these two mines ("reference scenarios"), ii) assessing the environmental performance of two alternative mining solutions ("alternative scenarios"), respectively the use of alternative explosive compositions (including their associated air emissions) and the implementation of a new blast design method. This assessment relies on representative sets of data primarily drawn from on-site operations and experimental results, completed with other data sources to fill the gaps. The environmental impacts are characterized based on the European EF (Environmental Footprint) life cycle impact assessment method. Firstly, among the 16 impact categories considered, the production of 1 ton of iron concentrate (33.5% Fe) in the Erzberg mine in particular potentially induces a total of 8.75 kg CO2-eq. The consumption of ferrosilicon in the concentration step (main contributor to 8 impact categories out of 16), of steel in the comminution step (main contributor to 2 impact categories), and of diesel by the machinery necessary for loading/hauling the ore (main contributor to 3 impact categories) stand for the main environmental hotspots in the Erzberg case. Secondly, the production of 1 ton of fluorspar concentrate (79.2% CaF2) in the Lujar mine potentially induces a total of 174 kg CO2-eq. The consumption of diesel by the machinery and the

关键词： Vegetation optical depth   Africa   Biomass   AMSR2   IB X-VOD   LPRM   LPDR  

摘要： Vegetation optical depth (VOD) retrieved from microwave observations has been found to be useful to monitor the dynamics of the vegetation features at global scale. Particularly, many applications could be developed in several fields of research (ecology, water and carbon cycle, etc.) from VOD products retrieved from the SMOS and SMAP observations at L-band, and from the combined AMSR-E (2002-2011)/AMSR2 (2012-present) observations at C-and X-bands. One of the main difficulties in retrieving VOD is that the microwave observations are sensitive to both the soil (mainly soil moisture) and vegetation (mostly VOD) features. The AMSR-E/2 sensors provide only mono-angular observations at two polarizations. These dual-channel observations may be strongly correlated so that retrieving SM and VOD simultaneously can be an ill-posed problem. Here, to overcome this problem, we proposed and evaluated a new retrieval approach from AMSR2 observations at X-band to produce a new X-VOD product. The X-VOD retrievals were based on the inversion of the X-MEB model, an extension of the L-MEB model (L-band microwave emission of the biosphere) to the X-band. The main originality in comparison to previous algorithms is that (i) only VOD was retrieved while SM was estimated from a reanalysis data set (ERA5-Land);(ii) model inversion was based on an innovative approach to initialize the cost function;and (iii) new values for the soil and vegetation X-MEB model parameters were calibrated. To evaluate the methodology, we performed the VOD retrievals over the whole African continent over 2014-2016, including a dry (2015) and a wet (2014) year. In a first step, we calibrated a set of three parameters: effective scattering albedo (omega), soil roughness (H-R) and VOD first guess (VODini). Several datasets of vegetation indices as Above-Ground Biomass (AGB), Leaf Area Index (LAI) and Normalized Difference Vegetation Index (NDVI) were chosen as reference data to optimize these model parameters. Glob

关键词： Water hyacinth   Potash pulping   Bio-compost   Black liquor   Handmade paper   Alternative livelihood  

摘要： Water hyacinth (WH) is considered as the worst aquatic weed in the world because of its rapid growth and fast spread into new areas of fresh water bodies. We investigated the potentiality of using WH as a raw material for production of handmade paper and compost in Bangladesh. Potash pulping was done using potassium hydroxide (KOH) at different alkali concentrations (8-12%) with a liquor to solid ratio of 7:1 at 145 degrees C for 2 h. The pulp was bleached using hydrogen peroxide (H2O2), and pulp properties (brightness, tear index and tensile index) of bleached and unbleached pulps were analyzed following the respective TAPPI standards. The produced black liquor was mixed with WH along with kitchen bio-wastes to produce compost. The properties of the compost were tested following the published protocols, i.e., wet digestion, Kjeldahl, vanadomolybdophosphoric acid, and Flame Spectrophotometry methods. Brightness, tensile index and tear index of bleached hand sheets were found to be 37.2%, 49.2 N m/g and 6.79 ***2/g, respectively suggesting significant contribution of bleaching on WH paper quality. Addition of black liquor significantly increased the nitrogen and potassium content of bio-waste compost. Thus, WH can be used as a raw material for making handmade paper while the process by-product can be supplemented to improve the nutritional quality of compost. Such cottage-industry fabrication of WH green products could be developed to control the infestation of WH in water bodies, and this technology may provide for new possible sustainable livelihood option.

关键词： Blast vibrations   stiffness ratio   bench face   cluster analysis   discriminant analysis  

摘要： This study tries to create alternative vibration prediction equations considering some important and neglected blast parameters. The target research parameters are stiffness ratio, blast dimensions and free face conditions. Alternative equations were created by classifying the blasts based on operational parameters. Also, cluster analysis and discriminant analysis methods were used to classify blasts into homogenous subgroups. Nine different predictor equations were developed based on scaled distance concept. The developed predictor models are quite promising. The research shows that before the application of complex modelling techniques, all the alternative predictive models should be investigated for mining sites.

关键词： Cell death  

摘要： Apoptosis is a defense mechanism against pre-cancerous and infected cells. Although the applicability of beta-ionone against diverse cancer cell lines has been exhaustively investigated, the apoptotic activity of terpenoid-like chalcones, as well as their mechanisms of action, is not well understood. Here we present a new terpenoid-like chalcone derivative (I) and its biological potential against HL-60 (leukemia), HCT-116 (colon), and SNB-19 (glioblastoma) cancer cell lines. Compound I showed cytotoxicity against over 90% of the tested cell lines. However, I has an IC50 slightly higher than doxorubicin, a DNA-binding cancer drug, which motivated us to investigate an alternative mechanism of action for I other than DNA-mediated. We performed an in silico structure-based pharmacophoric screening against various proteins, which indicated mitogen-activated protein kinase 5 (MAP3K5) as a potential protein target. Compound I was docked within its active site and was predicted to bind MAP3K5 with a comparable affinity to IM6, a cocrystallized ligand. Finally, we describe the reaction of a reduced glutathione adduct (GSH) with compound I and previously published derivatives bearing the substitutions 4-chloro (II), 4-bromo (III), and 4-nitro (IV) using HPLC-MS. We show that these are rapid reactions and that the products are stable for up to 24 h. Here, we suggest two alternative mechanisms (MAP3K5 inhibition and thiol reactivity) for the biological potential of a series of terpenoid-like chalcone derivatives. We anticipate that these findings can be explored to design additional derivatives with even more robust apoptotic activity.

关键词： Beeswax   Composite Electrode   Prussian blue   Hydrogen peroxide   Honeybee quality control  

摘要： The present paper describes a new way to construct composite electrodes by using beeswax as an alternative binder and graphite powder as the conductive phase. Beeswax can be an attractive binder since it is a biodegradable and renewable material. Also, it attributes to the composite material a good rigidity after dry at room temperature. The monitoring of hydrogen peroxide (H2O2) in honey is extremely important due to its antibacterial properties, which are vital for the maintenance of the hive. The determination of H2O2 by electrochemical techniques is widely noted in the literature, mainly using redox mediators or catalysts, such as Prussian blue (PB). Therefore, the proposed composite electrode was prepared with beeswax and graphite in n-hexane, and the PB was electrochemically synthesized by cyclic voltammetry. The constructed electrode showed a low resistance of electronic transfer (60 Omega), high electroactive surface area, and high electronic transference constant (1.73 x10(-3) cm s(-1)) when compared with other composite electrodes. The presence of PB on composite electrode allowed the amperometric determination of H2O2 with good linearity (R-2 = 0.997) at a concentration range of 1.0-180 mu mol L-1 H2O2, showing a sensitivity of 0.184 mu AL mu mol(-1). Consequently, it was possible to determine H2O2 accurately at three concentration levels in wild honey samples (RSD = 98.5-102%), suggesting the use of this alternative method for the quality control analysis of honey. (C) 2021 Elsevier Ltd. All rights reserved.