Search results for: oxygen ionic conductors

Authors: Svetlana Guryeva, Inna Kornienko, Elena Petersen

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At present, translational medicine is a rapidly developing branch of biomedicine. The main idea of translational medicine is a practical application of fundamental research. One of the possible applications for translational medicine is researching therapies that improve human age-related organism condition. To fill the gap between experiments and clinical practice, it is necessary to create the standardized system for the investigation of different effects on cellular aging models. In this study, primary human fibroblasts derived from patients of different ages were used as a cellular aging model. The senescence-associated β-galactosidase activity, lipofuscin, γ-H2AX, the reactive oxygen species level, and cell death markers (annexin V/propidium iodide) were used as biomarkers of the cell functional state. The effects of damaging exposures (oxidative stress and heat shock), potential positive factors (metformin and acetaminophen), and their combinations were investigated using the described biomarkers. Oxidative stress and heat shock caused the increase in the levels of all biomarkers, and only the cells from young patients partly coped with stress 3 days after the exposures. Metformin improved the state of pretreatment cells from young and old patients. The acetaminophen did not show significant changes in the biomarker levels compare to the action of metformin. This study proved the opportunity to develop a standardized screening system based on biomarkers of the cell functional state to identify potential positive or negative effects of some physical and chemical exposures. Moreover, such a system can be useful for the aims of regenerative medicine to determine the effect of cell pretreatment before transplantation.

Keywords: biomarkers, primary fibroblasts, regenerative medicine, senescence, test system, translational medicine

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Authors: Lamzira Ebralidze, Aleksandre Tsertsvadze, Dali Berashvili, Aliosha Bakuridze

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Nowadays, there is an increasing demand for biologically active substances from vegetable, animal, and mineral resources. In terms of the use of natural compounds, pharmaceutical, cosmetic, and nutrition industry has big interest. The biggest drawback of conventional extraction methods is the need to use a large volume of organic extragents. The removal of the organic solvent is a multi-stage process. And their absolute removal cannot be achieved, and they still appear in the final product as impurities. A large amount of waste containing organic solvent damages not only human health but also has the harmful effects of the environment. Accordingly, researchers are focused on improving the extraction methods, which aims to minimize the use of organic solvents and energy sources, using alternate solvents and renewable raw materials. In this context, green extraction principles were formed. Green Extraction is a need of today’s environment. Green Extraction is the concept, and it totally corresponds to the challenges of the 21st century. The extraction of biologically active compounds based on green extraction principles is vital from the view of preservation and maintaining biodiversity. Novel technologies of green extraction are known, such as "cold methods" because during the extraction process, the temperature is relatively lower, and it doesn’t have a negative impact on the stability of plant compounds. Novel technologies provide great opportunities to reduce or replace the use of organic toxic solvents, the efficiency of the process, enhance excretion yield, and improve the quality of the final product. The objective of the research is the development of green technologies of flavonoids containing preparations. Methodology: At the first stage of the research, flavonoids containing preparations (Tincture Herba Leonuri, flamine, rutine) were prepared based on conventional extraction methods: maceration, bismaceration, percolation, repercolation. At the same time, the same preparations were prepared based on green technologies, microwave-assisted, UV extraction methods. Product quality characteristics were evaluated by pharmacopeia methods. At the next stage of the research technological - economic characteristics and cost efficiency of products prepared based on conventional and novel technologies were determined. For the extraction of flavonoids, water is used as extragent. Surface-active substances are used as co-solvent in order to reduce surface tension, which significantly increases the solubility of polyphenols in water. Different concentrations of water-glycerol mixture, cyclodextrin, ionic solvent were used for the extraction process. In vitro antioxidant activity will be studied by the spectrophotometric method, using DPPH (2,2-diphenyl-1- picrylhydrazyl) as an antioxidant assay. The advantage of green extraction methods is also the possibility of obtaining higher yield in case of low temperature, limitation extraction process of undesirable compounds. That is especially important for the extraction of thermosensitive compounds and maintaining their stability.

Keywords: extraction, green technologies, natural resources, flavonoids

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Authors: D. Kuvshinov, A. Siswanto, J. Lozano-Parada, W. Zimmerman

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Ozone is well known as a powerful fast reaction rate oxidant. The ozone based processes produce no by-product left as a non-reacted ozone returns back to the original oxygen molecule. Therefore an application of ozone is widely accepted as one of the main directions for a sustainable and clean technologies development. There are number of technologies require ozone to be delivered to specific points of a production network or reactors construction. Due to space constrains, high reactivity and short life time of ozone the use of ozone generators even of a bench top scale is practically limited. This requires development of mini/micro scale ozone generator which can be directly incorporated into production units. Our report presents a feasibility study of a new micro scale rector for ozone generation (MROG). Data on MROG calibration and indigo decomposition at different operation conditions are presented. At selected operation conditions with residence time of 0.25 s the process of ozone generation is not limited by reaction rate and the amount of ozone produced is a function of power applied. It was shown that the MROG is capable to produce ozone at voltage level starting from 3.5kV with ozone concentration of 5.28E-6 (mol/L) at 5kV. This is in line with data presented on numerical investigation for a MROG. It was shown that in compare to a conventional ozone generator, MROG has lower power consumption at low voltages and atmospheric pressure. The MROG construction makes it applicable for emerged and dry systems. With a robust compact design MROG can be used as incorporated unit for production lines of high complexity.

Keywords: dielectric barrier discharge (DBD), micro reactor, ozone, plasma

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Authors: Ibrahim Al-Suraihy, Abdellaziz Doghmane, Zahia Hadjoub

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We discuss in this work the elastic properties by using acoustic microscopes to measure Rayleigh and longitudinal wave velocities in a no radiated and radiated sodium borate glasses X2Na2O-X2B2O3 with 0 ≤ x ≤ 27 (mol %) at microscopic resolution. The acoustic material signatures were first measured, from which the characteristic surface velocities were determined.Longitudinal and shear ultrasonic velocities were measured in a different composition of sodium borate glass samples before and after irradiation with γ-rays. Results showed that the effect due to increasing sodium oxide content on the ultrasonic velocity appeared more clearly than due to γ-radiation. It was found that as Na2O composition increases, longitudinal velocities vary from 3832 to 5636 m/s in irradiated sample and it vary from 4010 to 5836 m/s in high radiated sample by 10 dose whereas shear velocities vary from 2223 to 3269 m/s in irradiated sample and it vary from 2326 m/s in low radiation to 3385 m/s in high radiated sample by 10 dose. The effect of increasing sodium oxide content on ultrasonic velocity was very clear. The increase of velocity was attributed to the gradual increase in the rigidity of glass and hence strengthening of network due to gradual change of boron atoms from the three-fold to the four-fold coordination of oxygen atoms. The ultrasonic velocities data of glass samples have been used to find the elastic modulus. It was found that ultrasonic velocity, elastic modulus and microhardness increase with increasing barium oxide content and increasing γ-radiation dose.

Keywords: mechanical properties X2Na2O-X2B2O3, acoustic signature, SAW velocities, additives, gamma-radiation dose

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Authors: Marisa Chrysochoou, James Mahoney, Kay Wille

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Pyrrhotite is an iron-sulfide mineral which releases sulfuric acid when exposed to water and oxygen. The presence of this mineral in concrete foundations across Connecticut and Massachusetts in the US is causing in some cases premature failure. This has resulted in a devastating crisis for all parties affected by this type of failure which can take up to 15-25 years before internal damage becomes visible on the surface. This study shares laboratory results aimed to investigate the fundamental mechanisms of pyrrhotite reaction and to further the understanding of its deterioration kinetics within concrete. This includes the following analyses: total sulfur, wavelength dispersive X-ray fluorescence, expansion, reaction rate combined with ion-chromatography, as well as damage evolution using electro-chemical acceleration. This information is coupled to a statistical analysis of over 150 analyzed concrete foundations. Those samples were obtained and process using a developed and validated sampling method that is minimally invasive to the foundation in use, provides representative samples of the concrete matrix across the entire foundation, and is time and cost-efficient. The processed samples were then analyzed using a developed modular testing method based on total sulfur and wavelength dispersive X-ray fluorescence analysis to quantify the amount of pyrrhotite. As part of the statistical analysis the results were grouped into the following three categories: no damage observed and no pyrrhotite detected, no damage observed and pyrrhotite detected and damaged observed and pyrrhotite detected. As expected, a strong correlation between amount of pyrrhotite, age of the concrete and damage is observed. Information from the laboratory investigation and from the statistical analysis of field samples will aid in forming a scientific basis to support the decision process towards sustainable financial and administrative solutions by state and local stakeholders.

Keywords: concrete, pyrrhotite, risk of failure, statistical analysis

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Authors: Ivan Zupan, Tomislav Saric, Suzana Tkalcic

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IMUNO-2865® is a commercially available, β–glucan based, natural hemicellulose compound with proven immunostimulative properties in people, domestic and some aquatic animals. During the experimental feeding trial with IMUNO-2865® in juvenile wild-caught chub under laboratory conditions, supplementation resulted in overall higher growth performance for all experimental groups regardless of the concentration of the added compound. The maximum, 5% concentration of the supplement, resulted in highest weight gain and calculated specific growth rate. In sea bream, as economically most important species in the Mediterranean aquaculture, significant increases in numbers of monocytes and heterophils were observed in the group supplemented with 2.5 % of IMUNO-2865® in the feed. An overall increase of erythrocytes was noted by the end of the experiment, although with variable distribution among groups. Blood Ca++ levels, total proteins, and total NH₃ were significantly higher after 60 days of feeding in all treatment groups compared to the control and remained elevated in the treated group following the secession of supplementation. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and serum paraoxonase PON1 (U/L) showed similar trends. All these parameters are playing a significant role in either oxygen supplementation of tissues, or anabolic and catabolic processes that on molecular levels contribute to the overall health and immune-building capacity of cells and tissues. The complete lack of mortality in sea bream and presented increases in cellular, biochemical and oxidative stress parameters in the blood suggest that the IMUNO-2865® represents a safe dietary supplement for in aquaculture, with an overall positive and potentially immunostimulative effect on farmed fish.

Keywords: IMUNO-2865®, β–glucans, Mediterranean aquaculture, fish imunnostimulans

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Authors: Andres Diaz Garcia

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The successful technological development of any bioproduct, including those of the biostimulant type, requires to adequately completion of a series of stages allied to different disciplines that are related to microbiological, engineering, pharmaceutical chemistry, legal and market components, among others. Engineering as a discipline has a key contribution in different aspects of fermentation processes such as the design and optimization of culture media, the standardization of operating conditions within the bioreactor and the scaling of the production process of the active ingredient that it will be used in unit operations downstream. However, all aspects mentioned must take into account many biological factors of the microorganism such as the growth rate, the level of assimilation to various organic and inorganic sources and the mechanisms of action associated with its biological activity. This paper focuses on the practical experience within the Colombian Corporation for Agricultural Research (Agrosavia), which led to the development of a biostimulant bioproduct based on native rhizobacteria Bacillus amyloliquefaciens, oriented mainly to plant growth promotion in cape gooseberry nurseries and fruit crops in Colombia, and the challenges that were overcome from the expertise in the area of engineering. Through the application of strategies and engineering tools, a culture medium was optimized to obtain concentrations higher than 1E09 CFU (colony form units)/ml in liquid fermentation, the process of biomass production was standardized and a scale-up strategy was generated based on geometric (H/D of bioreactor relationships), and operational criteria based on a minimum dissolved oxygen concentration and that took into account the differences in the capacity of control of the process in the laboratory and pilot scales. Currently, the bioproduct obtained through this technological process is in stages of registration in Colombia for cape gooseberry fruits for export.

Keywords: biochemical engineering, liquid fermentation, plant growth promoting, scale-up process

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Authors: Amin Abbasi, Fariborz Shekari, Seyed Bahman Mousavi

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Seed aging during storage is a complex biochemical and physiological processes that can lead to reduce seed germination. This phenomenon associated with increasing of total antioxidant activity during aging. To study the effects of hormones on seed aging, aged wheat seeds (control, 90 and 80% viabilities) were treated with GA3, Salicylic Acid, and paclobutrazol and antioxidant system were investigated as molecular biomarkers for seed vigor. The results showed that, seed priming treatment significantly affected germination percentage, normality seedling percentage, H2O2, MDA, CAT, APX, and GPX activates. Maximum germination percentage achieve in GA3 priming in control treatment. Germination percentage and normal seedling percentage increased in other GA3 priming treatment compared with other hormones. Also aging increased MDA, H2O2 content. MDA is considered sensitive marker commonly used for assessing membrane lipid peroxidation and H2O2result in toxicity to cellular membrane system and damages to plant cells. Amount of H2O2 and MDA declined in GA3 treatment. CAT, GPX and APX activities were reduced by increasing the aging time and at different levels of priming. The highest APX activity was observed in Salicylic Acid control treatment and the highest GPX and CAT activity was obtained in GA3 control treatment. The lowest MDA and H2O2 showed in GA3 control treatment, too. Hormone priming increased Antioxidant enzyme activity and decreased amount of reactive oxygen space and malondialdehyde (MDA) under aging treatment. Also, GA3 priming treatments have a significant effect on germination percentage and number of normal seedling. Generally aging seed, increase ROS and lipid peroxidation. Antioxidant enzymes activity of aged seeds increased after hormone priming.

Keywords: hormones priming, wheat, aging seed, antioxidant, lipid peroxidation

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Authors: Nandini Nalika, Suhel Parvez

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Nanotechnology has emerged to play a vital role in developing all through the industrial world with an immense production of nanomaterials including nanoparticles (NPs). Many toxicological studies have confirmed that due to unique small size and physico-chemical properties of NPs (1-100nm), they can be potentially hazardous. Metallic NPs of small size have been shown to induce higher levels of cellular oxidative stress and can easily pass through the Blood Brain Barrier (BBB) and significantly accumulate in brain. With the wide applications of titanium dioxide nanoparticles (TNPs) in day-to-day life in form of cosmetics, paints, sterilisation and so on, there is growing concern regarding the deleterious effects of TNPs on central nervous system and mitochondria appear to be important cellular organelles targeted to the pro-oxidative effects of NPs and an important source that contribute significantly for the production of reactive oxygen species after some toxicity or an injury. The aim of our study was to elucidate the effect of TNPs in anatase form with different concentrations (5-50 µg/ml) following with various oxidative stress markers in isolated brain mitochondria as an in vitro model. Oxidative stress was determined by measuring the different oxidative stress markers like lipid peroxidation as well as the protein carbonyl content which was found to be significantly increased. Reduced glutathione content and major glutathione metabolizing enzymes were also modulated signifying the role of glutathione redox cycle in the pathophysiology of TNPs. The study also includes the mitochondrial enzymes (Complex 1, Complex II, complex IV, Complex V ) and the enzymes showed toxicity in a relatively short time due to the effect of TNPs. The study provide a range of concentration that were toxic to the neuronal cells and data pointing to a general toxicity in brain mitochondria by TNPs, therefore, it is in need to consider the proper utilization of NPs in the environment.

Keywords: mitochondria, nanoparticles, brain, in vitro

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Authors: John Justo Ambuchi, Zhaohan Zhang, Yujie Feng

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Quick development and usage of nanotechnology have resulted to massive use of various nanoparticles, such as iron oxide nanoparticles (IONPs) and multi-wall carbon nanotubes (MWCNTs). Thus, this study investigated the role of IONPs and MWCNTs in enhancing bioenergy recovery. Results show that IONPs at a concentration of 750 mg/L and MWCNTs at a concentration of 1500 mg/L induced faster substrate utilization and biogas production rates than the control. IONPs exhibited higher carbon oxygen demand (COD) removal efficiency than MWCNTs while on the contrary, MWCNT performance on biogas generation was remarkable than IONPs. Furthermore, scanning electron microscopy (SEM) investigation revealed extracellular polymeric substances (EPS) excretion from AGS had an interaction with nanoparticles. This interaction created a protective barrier to microbial consortia hence reducing their cytotoxicity. Microbial community analyses revealed genus predominance of bacteria of Anaerolineaceae and Longilinea. Their role in biodegradation of the substrate could have highly been boosted by nanoparticles. The archaea predominance of the genus level of Methanosaeta and Methanobacterium enhanced methanation process. The presence of bacteria of genus Geobacter was also reported. Their presence might have significantly contributed to direct interspecies electron transfer in the system. Exposure of AGS to nanoparticles promoted direct interspecies electron transfer among the anaerobic fermenting bacteria and their counterpart methanogens during the anaerobic digestion process. This results provide useful insightful information in understanding the response of microorganisms to IONPs and MWCNTs in the complex natural environment.

Keywords: anaerobic granular sludge, extracellular polymeric substances, iron oxide nanoparticles, multi-wall carbon nanotubes

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Authors: Afshin Zohdi, Selçuk Özdemir, Mustafa Aksoy

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Tungsten carbide-cobalt (WC-Co) is a widely utilized material for cold forming dies, including those employed in fastener production. In this study, we investigated the effectiveness of the pack boriding method in improving the surface properties of WC-Co cold forging dies. The boriding process involved embedding WC-Co samples, along with a steel control sample, within a chamber made of H13 tool steel. A boriding powder mixture was introduced into the chamber, which was then sealed using a paste. Subsequently, the samples were subjected to a temperature of 700°C for 5 hours in a furnace. Microstructural analysis, including cross-sectional examination and scanning electron microscopy (SEM), confirmed successful boron diffusion and its presence on the surface of the borided samples. The microhardness of the borided layer was significantly increased (3980 HV1) compared to the unborided sample (1320 HV3), indicating enhanced hardness. The borided layer exhibited an acceptable thickness of 45 microns, with a diffusion coefficient of 1.125 × 10-7 mm²/s, signifying a moderate diffusion rate. Energy-dispersive X-ray spectroscopy (EDS) mapping revealed an increase in boron content, desirable for the intended purpose, while an undesired increase in oxygen content was observed. Furthermore, the pin-on-disk wear test demonstrated a reduction in friction coefficient, indicating improved mechanical and tribological properties of the surface. The successful implementation of the pack boriding process highlights its potential for enhancing the performance of WC-Co cold forging dies.

Keywords: WC-Co, cold forging dies, pack boriding, surface hardness, wear resistance, microhardness, diffusion coefficient, scanning electron microscopy, energy-dispersive X-ray spectroscopy

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Authors: Hai Zhou, Wenzhi Zhao

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Water is one of the most important factors limiting plant growth and development in desert ecosystems. In order to understand how desert shrubs cope with variation in water sources over time, it is important to understand plant–water relations in desert-oasis ecotone. We selected the typical desert shrubs: Nitraria sibirica, Calligonum mongolicum and Haloxylon ammodendron of 5-, 10-, 20- and 40-year old as the research species, to study the seasonal variation of plant water sources and response to precipitation in the desert-oasis ecotone of Linze, Northwestern China. We examined stable isotopic ratios of oxygen (δ18O) in stem water of desert shrubs as well as in precipitation, groundwater, and soil water in different soil layers and seasons to determine water sources for the shrubs. We found that the N. sibirica and H. ammodendron of 5-, 10-year old showed significant seasonal variation characteristics of δ18O value of stem water and water sources. However, the C. mongolicum and 20- and 40-year H. ammodendron main water sources were from deep soil water and groundwater, and less response to precipitation pulse. After 22.4 mm precipitation, the contribution of shallow soil water (0-50cm) to the use of N. sibirica increased from 6.7% to 36.5%; the C. mongolicum rarely use precipitation that were about 58.29% and 23.51%, absorbed from the deep soil water and groundwater; the contribution of precipitation to use of H. ammodendron had significantly differences among the four ages. The H. ammodendron of 5- and 10-year old about 86.3% and 42.5% water sources absorbed from the shallow soil water after precipitation. However, the contribution to 20- and 40-year old plant was less than 15%. So, the precipitation was one of the main water sources for desert shrubs, but the species showed different water utilization. We conclude that the main water source of the N. sibirica and H. ammodendron of 5-, 10-year was soil water recharged by precipitation, but the deeply rooted H. ammodendron of 20‐ and 40‐year‐old and the C. mongolicum have the ability to exploit a deep and reliable water source.

Keywords: water use pattern, water resource, stable isotope, seasonal change, precipitation pulse

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Authors: Ana Maria Muț, Georgeta Coneac, Ioana Olariu, Ștefana Avram, Ioana Zinuca Pavel, Ionela Daliana Minda, Lavinia Vlaia, Cristina Adriana Dehelean, Corina Danciu

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Oregano essential oil is obtained from different parts of the plant Origanum vulgare (fam. Lamiaceae) and carvacrol and thymol are primary components, widely recognized for their antimicrobial activity, as well as their antiviral and antifungal properties. Poloxamers are triblock copolymers (Pluronic®), formed of three non-ionic blocks with a hydrophobic polyoxypropylene central chain flanked by two polyoxyethylene hydrophilic chains. They are known for their biocompatibility, sensitivity to temperature changes (sol-to-gel transition of aqueous solution with temperature increase), but also for their amphiphilic and surface active nature determining the formation of micelles, useful for solubilization of different hydrophobic compounds such as the terpenes and terpenoids contained in essential oils. Thus, these polymers, listed in European and US Pharmacopoeia and approved by FDA, are widely used as solubilizers and gelling agents for various pharmaceutical preparations, including topical hydrogels. The aim of this study was to investigate the posibility of solubilizing oregano essential oil (OEO) in polymeric micelles using polyoxypropylene (PPO)-polyoxyethylene (PEO)-polyoxypropylene (PPO) triblock polymers to obtain semisolid systems suitable for topical application. A formulation screening was performed, using Pluronic® F-127 in concentration of 20%, Pluronic® L-31, Pluronic® L-61 and Pluronic® L-62 in concentration of 0.5%, 0.8% respectively 1% to obtain the polymeric micelles-based systems. Then, to each selected system, with or without 10% absolute ethanol, 5% or 8% OEO was added. The obtained transparent poloxamer-based hydrogels containing solubilized OEO were further evaluated for pH, rheological characteristics (flow behaviour, viscosity, consistency and spreadability), using consacrated techniques like potentiometric titration, stationary shear flow test, penetrometric method and parallel plate method. Also, in vitro release and permeation of carvacrol from the hydrogels was carried out, using vertical diffusion cells and synthetic hydrophilic membrane and porcine skin respectively. The pH values and rheological features of all tested formulations were in accordance with official requirements for semisolid cutaneous preparations. But, the formulation containing 0.8% Pluronic® L-31, 10% absolute ethanol, 8% OEO and water and the formulation with 1% Pluronic® L-31, 5% OEO and water, produced the highest cumulative amounts of carvacrol released/permeated through the membrane. The present study demonstrated that oregano essential oil can be successfully solubilized in the investigated poloxamer-based hydrogels. These systems can be further investigated as potential topical therapy for cutaneous papillomas. Funding: This research was funded by Project PN-III-P1-1.1-TE2019-0130, Contract number TE47, Romania.

Keywords: oregano essential oil, carvacrol, poloxamer, topical hydrogels

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Authors: Pietro P. Falciglia, Erica Gagliano, Vincenza Brancato, Alfio Catalfo, Guglielmo Finocchiaro, Guido De Guidi, Stefano Romano, Paolo Roccaro, Federico G. A. Vagliasindi

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Cesium-137 (¹³⁷Cs) is a major radionuclide in spent nuclear fuel processing, and it represents the most important cause of contamination related to nuclear accidents. Cesium-137 has long-term radiological effects representing a major concern for the human health. Several physico-chemical methods have been proposed for ¹³⁷Cs removal from impacted water: ion-exchange, adsorption, chemical precipitation, membrane process, coagulation, and electrochemical. However, these methods can be limited by ionic selectivity and efficiency, or they present very restricted full-scale application due to equipment and chemical high costs. On the other hand, adsorption is considered a more cost-effective solution, and activated carbons (ACs) are known as a low-cost and effective adsorbent for a wide range of pollutants among which radionuclides. However, adsorption of Cs onto ACs has been investigated in very few and not exhaustive studies. In addition, exhausted activated carbons are generally discarded in landfill, that is not an eco-friendly and economic solution. Consequently, the regeneration of exhausted ACs must be considered a preferable choice. Several alternatives, including conventional thermal-, solvent-, biological- and electrochemical-regeneration, are available but are affected by several economic or environmental concerns. Microwave (MW) irradiation has been widely used in industrial and environmental applications and it has attracted many attentions to regenerating activated carbons. The growing interest in MW irradiation is based on the passive ability of the irradiated medium to convert a low power irradiation energy into a rapid and large temperature increase if the media presents good dielectric features. ACs are excellent MW-absorbers, with a high mechanical strength and a good resistance towards heating process. This work investigates the feasibility of MW irradiation for the regeneration of Cs-exhausted ACs. Adsorption batch experiments were carried out using commercially available granular activated carbon (GAC), then Cs-saturated AC samples were treated using a controllable bench-scale 2.45-GHz MW oven and investigating different adsorption-regeneration cycles. The regeneration efficiency (RE), weight loss percentage, and textural properties of the AC samples during the adsorption-regeneration cycles were also assessed. Main results demonstrated a relatively low adsorption capacity for Cs, although the feasibility of ACs was strictly linked to their dielectric nature, which allows a very efficient thermal regeneration by MW irradiation. The weight loss percentage was found less than 2%, and an increase in RE after three cycles was also observed. Furthermore, MW regeneration preserved the pore structure of the regenerated ACs. For a deeper exploration of the full-scale applicability of MW regeneration, further investigations on more adsorption-regeneration cycles or using fixed-bed columns are required.

Keywords: adsorption mechanisms, cesium, granular activated carbons, microwave regeneration

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Authors: Morteza Taherinezhad, Ahmad Reza Rabbani, Morteza Asemani, Rudy Swennen

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Oil-oil correlation is one of the most important issues in geochemical studies that enables to classify oils genetically. Oil-oil correlation is generally estimated based on non-polar fractions of crude oil (e.g., saturate and aromatic compounds). Despite several advantages, the drawback of using these compounds is their susceptibility of being affected by secondary processes. The polar fraction of crude oil (e.g., asphaltenes) has similar characteristics to kerogen, and this structural similarity is preserved during migration, thermal maturation, biodegradation, and water washing. Therefore, these structural characteristics can be considered as a useful correlation parameter, and it can be concluded that asphaltenes from different reservoirs with the same genetic signatures have a similar origin. Hence in this contribution, an integrated study by using both non-polar and polar fractions of oil was performed to use the merits of both fractions. Therefore, five oil samples from oil fields in the Persian Gulf were studied. Structural characteristics of extracted asphaltenes were investigated by Fourier transform infrared (FTIR) spectroscopy. Graphs based on aliphatic and aromatic compounds (predominant compounds in asphaltenes structure) and sulphoxide and carbonyl functional groups (which are representatives of sulphur and oxygen abundance in asphaltenes) were used for comparison of asphaltenes structures in different samples. Non-polar fractions were analyzed by GC-MS. The study of asphaltenes showed the studied oil samples comprise two oil families with distinct genetic characteristics. The first oil family consists of Salman and Reshadat oil samples, and the second oil family consists of Resalat, Siri E, and Siri D oil samples. To validate our results, biomarker parameters were employed, and this approach completely confirmed previous results. Based on biomarker analyses, both oil families have a marine source rock, whereby marl and carbonate source rocks are the source rock for the first and the second oil family, respectively.

Keywords: biomarker, non-polar fraction, oil-oil correlation, petroleum geochemistry, polar fraction

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Authors: Belahmadi M. S. O., Abdessemed A., Benchiheub M., Doukali H., Kaid Kasbah K. M.

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The aim of this study is to evaluate the quality of leachate generated by the Batna landfill site, and to verify the performance of various advanced oxidation processes, in particular the Fenton and Photo-Fenton systems combined with biological treatment to eliminate the recalcitrant organic matter contained in this effluent, and to preserve reverse osmosis membranes used for leachate treatment. The average values obtained are compared with national and international discharge standards. The results of physico-chemical analyses show that the leachate has an alkaline pH =8.26 and a high organic load with a low oxygen content. Mineral pollution is represented by high conductivity (38.3 mS/cm), high Kjeldahl nitrogen content (1266.504 mg/L) and ammoniacal nitrogen (1098.384 mg/L). The average pollution indicator parameters measured were: BOD5 = 1483.333 mg O2 /L, COD = 99790.244 mg O 2/L, TOC = 22400 mg C/L. These parameters exceed Algerian standards. Hence, there is a necessity to treat this effluent before discharging it into the environment. A comparative study was carried out to estimate the efficiency of two oxidation processes. Under optimum reaction conditions, TOC removal efficiencies of 63.43% and 73.4% were achieved for the Fenton and Photo-Fenton processes, respectively. COD removal rates estimated at 88% and 99.5% for the Fenton and Photo- Fenton processes, respectively. In addition, the Photo-Fenton + bacteria + micro- algae hybrid treatment gave removal efficiencies of around 92.24% for TOC and 99.9% for COD; -0.5 for AOS and 0.01 for CN. The results obtained during this study showed that a hybrid approach combining the PhotoFenton process and biological treatment appears to be a highly effective alternative for achieving satisfactory treatment, which aimed at exploiting the advantages of this method in terms of organic pollutant removal.

Keywords: leachate, landfill, advanced oxidation processes, Fenton and Photo-Fenton systems, biological treatment, organic pollutants

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Authors: Suvidha Gupta, R. A. Pandey, Sanjay Pawar

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The effluents from various food processing industries are found with high BOD, COD, suspended solids, nitrate, and phosphate. Mixotrophic growth of microalgae using food processing industrial wastewater as an organic carbon source has emerged as more effective and energy intensive means for the nutrient removal and COD reduction. The present study details the treatment of non-sterilized unfiltered food processing industrial wastewater by microalgae for nutrient removal as well as to determine the tolerance to COD by taking different dilutions of wastewater. In addition, the effect of different inoculum percentages of microalgae on removal efficiency of the nutrients for given dilution has been studied. To see the effect of dilution and COD tolerance, the wastewater having initial COD 5000 mg/L (±5), nitrate 28 mg/L (±10), and phosphate 24 mg/L (±10) was diluted to get COD of 3000 mg/L and 1000 mg/L. The experiments were carried out in 1L conical flask by intermittent aeration with different inoculum percentage i.e. 10%, 20%, and 30% of Chlorella sp. isolated from nearby area of NEERI, Nagpur. The experiments were conducted for 6 days by providing 12:12 light- dark period and determined various parameters such as COD, TOC, NO3-- N, PO4-- P, and total solids on daily basis. Results revealed that, for 10% and 20% inoculum, over 90% COD and TOC reduction was obtained with wastewater containing COD of 3000 mg/L whereas over 80% COD and TOC reduction was obtained with wastewater containing COD of 1000 mg/L. Moreover, microalgae was found to tolerate wastewater containing COD 5000 mg/L and obtained over 60% and 80% reduction in COD and TOC respectively. The obtained results were found similar with 10% and 20% inoculum in all COD dilutions whereas for 30% inoculum over 60% COD and 70% TOC reduction was obtained. In case of nutrient removal, over 70% nitrate removal and 45% phosphate removal was obtained with 20% inoculum in all dilutions. The obtained results indicated that Microalgae assisted nutrient removal gives maximum COD and TOC reduction with 3000 mg/L COD and 20% inoculum. Hence, microalgae assisted wastewater treatment is not only effective for removal of nutrients but also can tolerate high COD up to 5000 mg/L and solid content.

Keywords: Chlorella sp., chemical oxygen demand, food processing industrial wastewater, mixotrophic growth

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Authors: Qin Ou, Yanghui Xu, Xintu Wang, Kim Maren Lompe, Gang Liu, Jan Peter Van Der Hoek

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Microplastics (MPs) can undergo the photooxidation process under ultraviolet (UV) exposure, which determines their transformation and fate in environments. The presence of dissolved organic matter (DOM) can interact with MPs and take participate in the photo-degradation of MPs. As an important DOM component, dissolved black carbon (DBC), widely distributed in aquatic environments, can accelerate or inhibit the sunlight-driven photo-transformation of environmental pollutants. However, the role and underlying mechanism of DBC in the photooxidation of MPs are not clear. Herein, the DBC (< 0.45 µm) was extracted from wood biochar and fractionated by molecular weight (i.e., <3 KDa, 3 KDa−30 KDa, 30 KDa−0.45 µm). The effects of DBC chemical composition (i.e., molecular weight and chemical structure) in DBC-mediated photo-transformation of polystyrene (PS) MPs were investigated. The results showed that DBC initially inhibited the photo-degradation of MPs due to light shielding. Under UV exposure for 6−24 h, the presence of 5 mg/L DBC decreased the carbonyl index of MPs compared to the control. This inhibitory effect of DBC was found to decrease with increasing irradiation time. Notably, DBC initially decreased but then increased the hydroxyl index with aging time, suggesting that the role of DBC may shift from inhibition to acceleration. In terms of the different DBC fractions, the results showed that the smallest fraction of DBC (<3 KDa) significantly accelerated the photooxidation of PS MPs since it acted as reactive oxygen species (ROS) generators, especially in promoting the production of ¹O₂ and ³DBC* and •OH. With the increase in molecular weight, the acceleration effect of DBC on the degradation of MPs was decreased due to the increase of light shielding and possible decrease of photosensitization ability. This study thoroughly investigated the critical role of DBC chemical composition in the photooxidation process, which helps to assess the duration of aging and transformation of MPs during long-term weathering in natural waters.

Keywords: microplastics, photo-degradation, dissolved black carbon, molecular weight, photosensitization

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Authors: L. Bammou, M. Belkhaouda R. Salghi, L. Bazzi, B. Hammouti

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Steel and steel-based alloys of different grades steel are extensively used in numerous applications where acid solutions are widely applied such as industrial acid pickling, industrial acid cleaning and oil-well acidizing. The use of chemical inhibitors is one of the most practical methods for the protection against corrosion in acidic media. Most of the excellent acid inhibitors are organic compounds containing nitrogen, oxygen, phosphorus and sulphur. The use of non-toxic inhibitors called green or eco-friendly environmental inhibitors is one of the solutions possible to prevent the corrosion of the material. These advantages have incited us to draw a large part of program of our laboratory to examine natural substances as corrosion inhibitors such as: prickly pear seed oil, Argan oil, Argan extract, Fennel oil, Rosemary oil, Thymus oil, Lavender oil, Jojoba oil, Pennyroyal Mint oil, and Artemisia. In the present work, we investigate the corrosion inhibition of steel in 1 M HCl by junipers extract using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. The result obtained of junipers extract (JE) shows excellent inhibition properties for the corrosion of C38 steel in 1M HCl at 298K, and the inhibition efficiency increases with increasing of the JE concentration. The inhibitor efficiencies determined by weight loss, Tafel polarisation and EIS methods are in reasonable agreement. Based on the polarisation results, the investigated junipers extract can be classified as mixed inhibitor. The calculated structural parameters show increase of the obtained Rct values and decrease of the capacitance, Cdl, with JE concentration increase. It is suggested to attribute this to the increase of the thickness of the adsorption layer at steel surface. The adsorption model obeys to the Langmuir adsorption isotherm. The adsorption process is a spontaneous and exothermic process.

Keywords: corrosion inhibition, steel, friendly inhibitors, Tafel polarisation

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Authors: Natalia V. Beloglazova, Pieterjan Lenain, Martin Hedstrom, Dietmar Knopp, Sarah De Saeger

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In recent years polycyclic aromatic hydrocarbons (PAHs), which represent a hazard to humans and entire ecosystem, have been receiving an increased interest due to their mutagenic, carcinogenic and endocrine disrupting properties. They are formed in all incomplete combustion processes of organic matter and, as a consequence, ubiquitous in the environment. Benzo(a)pyrene (BaP) is on the priority list published by the Environmental Agency (US EPA) as the first PAH to be identified as a carcinogen and has often been used as a marker for PAHs contamination in general. It can be found in different types of water samples, therefore, the European Commission set up a limit value of 10 ng L–1 (10 ppt) for BAP in water intended for human consumption. Generally, different chromatographic techniques are used for PAHs determination, but these assays require pre-concentration of analyte, create large amounts of solvent waste, and are relatively time consuming and difficult to perform on-site. An alternative robust, stand-alone, and preferably cheap solution is needed. For example, a sensing unit which can be submerged in a river to monitor and continuously sample BaP. An affinity sensor based on capacitive transduction was developed. Natural antibodies or their synthetic analogues can be used as ligands. Ideally the sensor should operate independently over a longer period of time, e.g. several weeks or months, therefore the use of molecularly imprinted polymers (MIPs) was discussed. MIPs are synthetic antibodies which are selective for a chosen target molecule. Their robustness allows application in environments for which biological recognition elements are unsuitable or denature. They can be reused multiple times, which is essential to meet the stand-alone requirement. BaP is a highly lipophilic compound and does not contain any functional groups in its structure, thus excluding non-covalent imprinting methods based on ionic interactions. Instead, the MIPs syntheses were based on non-covalent hydrophobic and π-π interactions. Different polymerization strategies were compared and the best results were demonstrated by the MIPs produced using electropolymerization. 4-vinylpyridin (VP) and divinylbenzene (DVB) were used as monomer and cross-linker in the polymerization reaction. The selectivity and recovery of the MIP were compared to a non-imprinted polymer (NIP). Electrodes were functionalized with natural receptor (monoclonal anti-BaP antibody) and with MIPs selective towards BaP. Different sets of electrodes were evaluated and their properties such as sensitivity, selectivity and linear range were determined and compared. It was found that both receptor can reach the cut-off level comparable to the established ML, and despite the fact that the antibody showed the better cross-reactivity and affinity, MIPs were more convenient receptor due to their ability to regenerate and stability in river till 7 days.

Keywords: antibody, benzo(a)pyrene, capacitive sensor, MIPs, river water

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Authors: Adam N. Bell, Sarina J. Ergas, Michael Nystrom, Nathan P. Brennan, Kevan L. Main

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Integrated Multi-Trophic Aquaculture systems (IMTA) have the potential to improve the sustainability of seafood production, generate organic fertilizer and feed, remove waste discharges and reduce energy use. IMTA can include periphyton biofilters where algae and microbes grow on surfaces, along with caught detritus and amphipods. Periphyton biofilters provide many advantages: nitrification, denitrification, primary production and ecological diversity. The goal of this study was to determine how biofilter hydraulic residence time (τ) effects periphyton biomass production, dissolved oxygen (DO) and nutrient removal. A pilot scale recirculating aquaculture system (RAS) was designed, constructed and operated at different hydraulic residence times (τ= 1, 2, 4, 6, 8 hours per tank). For each τ, a conservative tracer study was conducted to investigate system hydrodynamics. Data on periphyton weights, pH, nitrogen species, phosphorus, temperature and DO were collected. The tracer study for τ =1 hour revealed that the normalized time < τ, indicating short-circuiting. Periphyton biomass production rate was relatively unaffected by τ (R_e<1 for all τ). Average ammonia nitrogen removal was > 75% for all trials. Nitrate and nitrite did not accumulate in the RAS for τ≥4 hours due to enhanced denitrification in anoxic zones. For τ≥4 hours DO concentration was at a maximum of 4 mg L-1 after 14:00, and decreased to 0 mg L-1 during nighttime. At τ=1 hour, the RAS stayed > 2 mg L-1 and DO was more evenly distributed. For the validation trial, the culture tank was stocked with Centropomus undecimalis (common snook) and the system was operated at τ= 1 hr. Preliminary results showed that a RAS with an integrated periphyton biofilter could support fish health with low nutrient concentrations DO > 6 mg L-1.

Keywords: sustainable aquaculture, resource recovery, nitrogen, microalgae, hydrodynamics, integrated multi-trophic aquaculture

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Authors: Kyngäs Helvi, Patala-Pudas, Kaakinen Pirjo

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It has been reported that COPD -patients may experience much emotional distress, which can compromise positive health outcomes. The aim of this study was to explore disease-related uncertainty as reported by Chronic Obstructive Pulmonary Disease (COPD) patients. Uncertainty was defined as a lack of confidence; negative feelings; a sense of confidence; and awareness of the sources of uncertainty. Research design was a non-experimental cross-sectional survey. The data (n=141) was collected by validated questionnaire during COPD -patients’ visits or admissions to a tertiary hospital. The response rate was 62%. The data was analyzed by statistical methods. Around 70% of the participants were male with COPD diagnosed many years ago. Fifty-four percent were under 65 years and used an electronic respiratory aid apparatus (52%) (oxygen concentrator, ventilator or electronic inhalation device). Forty-one percent of the participants smoked. Disease-related uncertainty was widely reported. Seventy-three percent of the participants had uncertainty about their knowledge of the disease, the pulmonary medication and nutrition. One-quarter (25%) did not feel sure about managing COPD exacerbation. About forty percent (43%) reported that they did not have a written exacerbation decision aid indicating how to act in relation to COPD symptoms. Over half of the respondents were uncertain about self-management behavior related to health habits such as exercise and nutrition. Over a third of the participants (37%) felt uncertain about self-management skills related to giving up smoking. Support from the care providers was correlated significantly with the patients’ sense of confidence. COPD -patients who felt no confidence stated that they received significantly less support in care. Disease-related uncertainty should be considered more closely and broadly in the patient care context, and those strategies within patient education that enhance adherence should be strengthened and incorporated into standard practice.

Keywords: adherence, COPD, disease-management, uncertainty

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Authors: Aastha Agarwal, Veena Sharma

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N-nitrosopyrollidine or NPYR is a tobacco-specific nitrosamine which upon intoxicated causes abnormal production of Reactive Oxygen Species disrupt the endogenous antioxidant system. The study was designed to evaluate the histological changes in lung tissue of Mus musculus in NPYR administered lungs and effect of isolated flavonoid 3,6-dihydroxy-(3’,4’,7’-trimethoxyphenyl)-chromen-4-one-7-glucoside (ITC) from experimental plant Indigofera tinctorial. Post treatment with isolated compound significantly restored the abnormal symptoms and changes in pulmonary tissue. Transverse section of mouse lung in control animals appeared as a thin lace. Histologically, most of the lung was arranged as alveoli which were thin walled structures made up of single layered squamous epithelial cells. In the transverse section of lung at 100 X will clearly show the component of alveoli, surround by a thin layer of connective tissue and blood vessels. Smaller bronchioles were lined by cuboidal epithelial cells while larger bronchioles were lined by ciliated columnar epithelium layer while in NPYR intoxicated lungs signs of vast pulmonary damages and carcinogenesis as alveolar damage, necrosis, DADs or defused alveolar damages hyperplasia, metaplasia, dysplasia and next stage of carcinogenesis were revealed. Treatment with ITC showed the significant positive changes in the lung tissue due to the side hydroxyl and methoxy groups in its structure which help in combating oxidative injuries and give protection from the free radicals generated during the metabolism of NPYR in body. Thus, histopathological analysis confirms the development of the cancerous conditions in the lung tissue in mice model and the protective effects of ITC.

Keywords: flavonoid, histopathology, Indigofera tinctoria, lung

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Authors: Tafadzwa Makonese, Harold Annegarn, Patricia Forbes

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Residential coal combustion is one of the largest sources of carbonaceous aerosols in the Highveld region of South Africa, significantly affecting the local and regional climate. In this study, we investigated single coal burning particles emitted when using different fire-ignition techniques (top-lit up-draft vs bottom-lit up-draft) and air ventilation rates (defined by the number of air holes above and below the fire grate) in selected informal braziers. Aerosol samples were collected on nucleopore filters at the SeTAR Centre Laboratory, University of Johannesburg. Individual particles (~700) were investigated using a scanning electron microscope equipped with an energy-dispersive X-ray spectroscopy (EDS). Two distinct forms of spherical organic particles (SOPs) were identified, one less oxidized than the other. The particles were further classified into "electronically" dark and bright, according to China et al. [2014]. EDS analysis showed that 70% of the dark spherical organic particles balls had higher (~60%) relative oxygen content than in the bright SOPs. We quantify the morphology of spherical organic particles and classify them into four categories: ~50% are bare single particles; ~35% particles are aggregated and form diffusion accretion chains; 10% have inclusions; and 5% are deformed due to impaction on filter material during sampling. We conclude that there are two distinct kinds of coal burning spherical organic particles and that dark SOPs are less volatile than bright SOPs. We also show that these spherical organic particles are similar in nature and characteristics to tar balls observed in biomass combustion, and that they have the potential to absorb sunlight thereby affecting the earth’s radiative budget and climate. This study provides insights on the mixing states, morphology, and possible formation mechanisms of these organic particles from residential coal combustion in informal stoves.

Keywords: spherical organic particles, residential coal combustion, fixed-bed, aerosols, morphology, stoves

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Authors: Emna Ketata, Wafa Farhat

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Introduction: Hyponatremia is defined by a blood sodium level of ≤ 136 mmol/L; it is associated with a high risk of morbidity and mortality in the emergency room. This was explained by transit disorders, including diarrhea and inappropriate antidiuretic hormone secretion (Syndrome of inappropriate antidiuretic hormone secretion). Pneumonia can cause dyspnea, stress-causing SIADH and digestive symptoms (diarrhea and vomiting). Aim: The purpose of this study was to determine the link between pneumonia and hyponatremia as a predictor of patient’s prognosis and intra-hospital mortality. Methodology: This is a prospective observational study over a period of 3 years in the emergency department. Inclusion :patients (age > 14 years), with clinical signs in favor of pneumonia. Natremia was measured. Natremia was classified as mild to moderate with a blood sodium level between 121 and 135 mmol/L and as severe with a blood sodium level ≤ 120 mmol/L. Results: This study showed an average serum sodium value of 135 mmol/L (range 114–159 mmol/L) in these patients. Hyponatremia was observed in 123 patients (43.6%), 115 patients (97,8%) had mild to moderate hyponatremia and 2,8% had severe hyponatremia. The mean age was 65±17 years with a sex ratio of 1.05. The main reason for consultation in patients with hyponatremia was cough in 58 patients (47.2%), and digestive symptoms were present in 25 patients (20.3. An altered state of consciousness was observed in 11 patients (3%). Patients with hyponatremia had greater heart rate (p=0.02),white blood cell count (p=0.009) , plasmatic lactate (p=0.002) and higher rate of pneumonia recurrence (p=0.001) .In addition, 80% of them have a positive CURB65 score (>=2). hyponatremia had higher rates of use of oxygen therapy compared to patients with normo-natremia (54% vs. 45%). The analytical study showed that hyponatremia is significantly associated with intra-hospital mortality with( p=0.01), severe hyponatremia p=0.04. Conclusion: Hyponatremia is a predictor of mortality and worse prognosis. Recognition of the pathophysiological mechanisms of hyponatremia in pneumonia will probably allow better management of it.

Keywords: oxygenotherapy, mortality, recurrence, positif curb65

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Authors: Oluyomi Stephen Adeyemi, Kentaro Kato

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Toxoplasma gondii is the etiological agent of toxoplasmosis, a common parasitic disease capable of infecting a range of hosts, including nearly one-third of the human population. Current treatment options for toxoplasmosis patients are limited. In consequence, toxoplasmosis represents a large global burden that is further enhanced by the shortcomings of the current therapeutic options. These factors underscore the need for better anti-T. gondii agents and/or new treatment approach. In the present study, we sought to find out whether preparing and capping nanoparticles (NPs) in amino acids, would enhance specificity toward the parasite versus the host cell. The selection of amino acids was premised on the fact that T. gondii is auxotrophic for some amino acids. The amino acid-nanoparticles (amino-NPs) were synthesized, purified and characterized following established protocols. Next, we tested to determine the anti-T. gondii activity of the amino-NPs using in vitro experimental model of infection. Overall, our data show evidence that supports enhanced and excellent selective action against the parasite versus the host cells by amino-NPs. The findings are promising and provide additional support that warrants exploring the prospects of NPs as alternative anti-parasite agents. In addition, the anti-parasite action by amino-NPs indicates that nutritional requirement of parasite may represent a viable target in the development of better alternative anti-parasite agents. Furthermore, data suggest the anti-parasite mechanism of the amino-NPs involves multiple cellular processes including the production of reactive oxygen species (ROS), modulation of hypoxia-inducing factor-1 alpha (HIF-1α) as well as the activation of kynurenine pathway. Taken together, findings highlight further, the prospects of NPs as alternative source of anti-parasite agents.

Keywords: drug discovery, infectious diseases, mode of action, nanomedicine

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Authors: Nur Farah Ain Zainee, Ahmad Ismail, Nazlina Ibrahim, Asmida Ismail

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The study of genus Halimeda in Malaysia is in the early stage due to less specific study on its taxonomy. Most of the previous research tend to choose other genus such as Caulerpa and Gracilaria because of the potential of being utilized. The identification of Halimeda is complex by the high morphological variation within individual species due to different types of habitat and the changes in composition of seawater. The study was completed to study the diversity and distribution of Halimeda in Malaysia and to identify the morphological and anatomical differences between Halimeda species. The methods which have been used for this study are collection of Halimeda and seawater, preservation of specimen, identification of the specimen including the preparation of the temporary slide and decalcification of the calcium layer by using diluted hydrochloric acid. The specimen were processed in laboratory and kept as herbarium specimen in Algae Herbarium, Universiti Kebangsaan Malaysia. Environmental parameters were tested by using YSI multiparameter probe and the recorded data were temperature, salinity, pH and dissolved oxygen. The nutrient content of seawater such as nitrate and phosphate were analysed by using Hach kit model DR 2000. In the present study, out of 330 herbarium specimen, ten species were identified as Halimeda cuneata, H. discoidea, H. macroloba, H. macrophysa, H. opuntia, H. simulans, H. stuposa, H. taenicola, H. tuna and H. velasquezii. Of these, five species were new record to Malaysia. They are Halimeda cuneata, H. macrophysa, H. stuposa, H. taenicola and H. velasquezii. H. opuntia was found as the most abundance species with wide distribution in Malaysia coastal area. Meanwhile, from the study of their distribution, two localities in which Pulau Balak Balak, Kudat and Pulau Langkawi, Kedah, were noted having high number of Halimeda species. As a conclusion, this study has successfully identified ten species of Halimeda of Malaysia with full description of morphological characteristics that may assist further researcher to differentiate and identify Halimeda.

Keywords: Distribution, diversity, Halimeda, morphological, taxonomy

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Authors: Faisal A. Salih

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Vinpocetine (Vin) is an ethyl ester of apovincamic acid and is a semisynthetic derivative of vincamine, an alkaloid from plants of the genus Periwinkle (plant) vinca minor. It was found that this compound stimulates cerebral metabolism: it increases the uptake of glucose and oxygen, as well as the consumption of these substances by the brain tissue. Vinpocetine enhances the flow of blood in the brain and has a vasodilating, antihypertensive, and antiplatelet effect. Vinpocetine seems to improve the human ability to acquire new memories and restore memories that have been lost. This drug has been clinically used for the treatment of cerebrovascular disorders such as stroke and dementia memory disorders, as well as in ophthalmology and otorhinolaryngology. It has no side effects, and no toxicity has been reported when using vinpocetine for a long time. For the quantitative determination of Vin in dosage forms, the HPLC methods are generally used. A promising alternative is potentiometry with Vin- selective electrode, which does not require expensive equipment and materials. Another advantage of the potentiometric method is that the pills and solutions for injections can be used directly without separation from matrix components, which reduces both analysis time and cost. In this study, it was found that the choice of a good plasticizer an electrode with the following membrane composition: PVC (32.8 wt.%), ortho-nitrophenyl octyl ether (66.6 wt.%), tetrakis-4-chlorophenyl borate (0.6 wt.%) exhibits excellent analytical performance: lower detection limit (LDL) 1.2•10⁻⁷ M, linear response range (LRR) 1∙10⁻³–3.9∙10⁻⁶ M, the slope of the electrode function 56.2±0.2 mV/decade). Vin masses per average tablet weight determined by direct potentiometry (DP) and potentiometric titration (PT) methods for the two different sets of 10 tablets were (100.35±0.2–100.36±0.1) mg for two sets of blister packs. The mass fraction of Vin in individual tablets, determined using DP, was (9.87 ± 0.02–10.16 ±0.02) mg, while the RSD was (0.13–0.35%). The procedure has very good reproducibility, and excellent compliance with the declared amounts was observed.

Keywords: vinpocetine, potentiometry, ion selective electrode, pharmaceutical analysis

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Authors: Panagiotis Svarnas, Polykarpos Papadopoulos

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Atmospheric-pressure cold plasmas continue to gain increasing interest for various applications due to their unique properties, like cost-efficient production, high chemical reactivity, low gas temperature, adaptability, etc. Numerous designs have been proposed for these plasmas production in terms of electrode configuration, driving voltage waveform and working gas(es). However, in order to exploit most of the advantages of these systems, the majority of the designs are based on dielectric-barrier discharges (DBDs) either in filamentary or glow regimes. A special category of the DBD-based atmospheric-pressure cold plasmas refers to the so-called plasma jets, where a carrier noble gas is guided by the dielectric barrier (usually a hollow cylinder) and left to flow up to the atmospheric air where a complicated hydrodynamic interplay takes place. Although it is now well established that these plasmas are generated due to ionizing waves reminding in many ways streamer propagation, they exhibit discrete characteristics which are better mirrored on the terms 'guided streamers' or 'plasma bullets'. These 'bullets' travel with supersonic velocities both inside the dielectric barrier and the channel formed by the noble gas during its penetration into the air. The present work is devoted to the interpretation of the electro-hydrodynamic effects that take place downstream of the dielectric barrier opening, i.e., in the noble gas-air mixing area where plasma bullet propagate under the influence of local electric fields in regions of variable noble gas concentration. Herein, we focus on the role of the local space charge and the residual ionic charge left behind after the bullet propagation in the gas flow field modification. The study communicates both experimental and numerical results, coupled in a comprehensive manner. The plasma bullets are here produced by a custom device having a quartz tube as a dielectric barrier and two external ring-type electrodes driven by sinusoidal high voltage at 10 kHz. Helium gas is fed to the tube and schlieren photography is employed for mapping the flow field downstream of the tube orifice. Mixture mass conservation equation, momentum conservation equation, energy conservation equation in terms of temperature and helium transfer equation are simultaneously solved, leading to the physical mechanisms that govern the experimental results. Namely, we deal with electro-hydrodynamic effects mainly due to momentum transfer from atomic ions to neutrals. The atomic ions are left behind as residual charge after the bullet propagation and gain energy from the locally created electric field. The electro-hydrodynamic force is eventually evaluated.

Keywords: atmospheric-pressure plasmas, dielectric-barrier discharges, schlieren photography, electro-hydrodynamic force

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Authors: E. Feizi Ashtiani, S. Jamshidi, M.H Niksokhan, A. Feizi Ashtiani

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Waste load allocation (WLA) policies may use multi-objective optimization methods to find the most appropriate and sustainable solutions. These usually intend to simultaneously minimize two criteria, total abatement costs (TC) and environmental violations (EV). If other criteria, such as inequity, need for minimization as well, it requires introducing more binary optimizations through different scenarios. In order to reduce the calculation steps, this study presents value index as an innovative decision making approach. Since the value index contains both the environmental violation and treatment costs, it can be maximized simultaneously with the equity index. It implies that the definition of different scenarios for environmental violations is no longer required. Furthermore, the solution is not necessarily the point with minimized total costs or environmental violations. This idea is testified for Haraz River, in north of Iran. Here, the dissolved oxygen (DO) level of river is simulated by Streeter-Phelps equation in MATLAB software. The WLA is determined for fish farms using multi-objective particle swarm optimization (MOPSO) in two scenarios. At first, the trade-off curves of TC-EV and TC-Inequity are plotted separately as the conventional approach. In the second, the Value-Equity curve is derived. The comparative results show that the solutions are in a similar range of inequity with lower total costs. This is due to the freedom of environmental violation attained in value index. As a result, the conventional approach can well be replaced by the value index particularly for problems optimizing these objectives. This reduces the process to achieve the best solutions and may find better classification for scenario definition. It is also concluded that decision makers are better to focus on value index and weighting its contents to find the most sustainable alternatives based on their requirements.

Keywords: waste load allocation (WLA), value index, multi objective particle swarm optimization (MOPSO), Haraz River, equity

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