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Wyniki wyszukiwania dla: SATURATED FATTY ACIDS
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Phase separation in poly(butylene terephthalate)-based materials prepared by solid-state modification
PublikacjaThe morphology of a series of poly(butylene terephthalate) (PBT)/fatty acid dimer diol (FADD)-based copolyesters prepared by solid-state modi fi cation (SSM) was studied. It was shown that in copolyesters containing less than 10 wt% FADD two different phases, i.e. a PBT crystalline phase and a PBT-rich amorphous phase, are present. The FADD residues were more or less homogeneously distributed throughout the interlamellar regions....
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Molecular Umbrellas Modulate the Selective Toxicity of Polyene Macrolide Antifungals
PublikacjaAntifungal polyene macrolide antibiotics Amphotericin B (AmB) and Nystatin (NYS) were conjugated through the ω-amino acid linkers with diwalled “molecular umbrellas” composed of spermidine-linked deoxycholic or cholic acids. The presence of “umbrella” substituents modulated biological properties of the antibiotics, especially their selective toxicity. Some of the AmB-umbrella conjugates demonstrated antifungal in vitro activity...
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Amino Acid Based Antimicrobial Agents – Synthesis and Properties
PublikacjaStructures of several dozen of known antibacterial, antifungal or antiprotozoal agents are based on the amino acid scaffold. In most of them, the amino acid skeleton is of a crucial importance for their antimicrobial activity, since very often they are structural analogs of amino acid intermediates of different microbial biosynthetic pathways. Particularly, some aminophosphonate or aminoboronate analogs of protein amino acids are...
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Bioactive Ingredients with Health-Promoting Properties of Strawberry Fruit (Fragaria x ananassa Duchesne)
PublikacjaStrawberries (Fragaria x ananassa Duchesne) belong to the berry group and are characterized primarily by delightful sensory properties. Due to their chemical composition, these fruits are a rich source of bioactive compounds that can modify the metabolic and physiological functions of the body. The aim of this work is to present the current state of research on bioactive ingredients found in these fruits in the context of their...
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Deposition and characterization of organic polymer thin films using a dielectric barrier discharge with different C2Hm/N2 (m = 2, 4, 6) gas mixtures
PublikacjaOrganic polymer thin films have been deposited on Si(100) and aluminum coated glass substrates by a dielectric barrier discharge (DBD) operated at medium pressure using different C2Hm/N2 (m = 2, 4, 6) gas mixtures. The deposited films were characterized by various spectroscopic techniques. Fourier transform infrared reflection absorption spectroscopy (FT-IRRAS) revealed the chemical functional groups present in the films. The surface...
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Future opportunities for products derived from black soldier fly (BSF) treatment as animal feed and fertilizer - A systematic review
PublikacjaThe pursuit of novel food products with good nutritional value for both direct and indirect human consumption is crucial. Given the nutritional benefits of insects and the sustainability of this sort of farming, using them as food for farmed animals is a promising alternative. In this regard, the black soldier fly (Hermetia illucens) is most capable of efficiently converting a wide variety of organic materials, from food waste...
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Phenolic Content and Related Antioxidant Activities in in vitro Cultures of Cephalotaxus Harringtonia L. Grown in Egypt
PublikacjaAbstract: Quantitative estimation of the total phenolics, total flavonoids, antioxidant activity and HPLC analysis of phenolic compounds in the mother plant, in vitro shooting and callus cultures of Cephalotaxus harringtonia L. grown in Egypt were measured. For shooting behaviour, using Woody plant medium (WPM) with 2 mg/l Benzyladinin (BA) in the second subculture gave the highest number of shootlet/explant (2.33 shootlet/explant)...
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Kobieta ciężarna i alkohol-toksyczny związek. Smółka noworodków jako materiał w diagnostyce spożywania alkoholu w czasie ciąży
PublikacjaKażda ilość alkoholu spożyta przez ciężarną kobietę może spowodować poronienie, przedwczesny poród, patologię łożyska, zahamowanie wzrostu wewnątrzmacicznego płodu i wystąpienie licznych wad wrodzonych wywołanych alkoholem, określanych wspólnie mianem spektrum płodowych zaburzeń alkoholowych - FASD. Mogą one objawiać się zaburzeniami psychicznymi i/lub fizycznymi. Współczesna diagnostyka u noworodków zespołu FASD opiera się najczęściej...
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Ordered titanium templates functionalized by gold films for biosensing applications – Towards non-enzymatic glucose detection
PublikacjaRecently, metal nanostructures evoke much interest due to application potential in highly sensitive detectors in biochemistry and medical diagnostics. In this work we report on preparation and characteristics of thin (1–100 nm) Au films deposited onto highly ordered structured titanium templates for SERS (Surface Enhanced Raman Spectroscopy) and electrochemical sensing. The Ti templates are formed by selective removal of TiO2 nanotubes...
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Experimental investigation of domestic micro-CHP based on the gas boiler fitted with ORC module
PublikacjaThe results of investigations conducted on the prototype of vapour driven micro-CHP unit integrated with a gas boiler are presented. The system enables cogeneration of heat and electric energy to cover the energy demand of household. The idea of such system is to produce electricity for own demand or for selling it to the electric grid – in such situation the system user will became the prosumer. A typical commercial gas boiler,...
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Obtaining and Characterization of the PLA/Chitosan Foams with Antimicrobial Properties Achieved by the Emulsification Combined with the Dissolution of Chitosan by CO2 Saturation
PublikacjaA new method of obtaining functional foam material has been proposed. The materials were created by mixing the poly lactic acid (PLA) solution in chloroform, chitosan (CS) dissolved in water saturated with CO2 and polyethylene glycol (PEG), and freeze-dried for removal of the solvents. The composite foams were characterized for their structural (SEM, FT-IR, density, porosity), thermal (DSC), functional (hardness, elasticity, swelling...
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Mechanical and physical assessment of epoxy, mineral, solvent-based, and water-soluble coating materials
PublikacjaThis paper assesses the behavior of mineral, epoxy (EP), solvent, and water-soluble coatings when exposed to salt and regular water for 28 days. Also, it evaluates the pull-off adhesion strength of the same coating materials applied to concrete slabs saturated with oil and water and dried with two different processes: air-dried for 28 days and air-dried for 14 days plus 14 days in the oven at 70 °C. Properties such as carbonation,...
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Obtaining and Characterization of the PLA/Chitosan Foams with Antimicrobial Properties Achieved by the Emulsification Combined with the Dissolution of Chitosan by CO2 Saturation
PublikacjaA new method of obtaining functional foam material has been proposed. The materials were created by mixing the poly lactic acid (PLA) solution in chloroform, chitosan (CS) dissolved in water saturated with CO2 and polyethylene glycol (PEG), and freeze-dried for removal of the solvents. The composite foams were characterized for their structural (SEM, FT-IR, density, porosity), thermal (DSC), functional (hardness, elasticity, swelling...
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Voriconazole-Based Salts Are Active against Multidrug-Resistant Human Pathogenic Yeasts
PublikacjaVoriconazole (VOR) hydrochloride is unequivocally converted into VOR lactates and valinates upon reaction with silver salts of organic acids. This study found that the anticandidal in vitro activity of these compounds was comparable or slightly better than that of VOR. The Candida albicans clinical isolate overexpressing CaCDR1/CaCDR2 genes, highly resistant to VOR, was apparently more susceptible to VOR salts. On the other hand,...
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Electron-impact ionization cross section of formic acid
PublikacjaExperimental electron-impact ionization cross sections of one of the simplest carboxylic acids, formic acid, are presented. The molecular target was studied in two independent experimental setups applying different methods: the total ion collection and the electron–impact mass spectrometry methods. Experimental data were taken at incident electron energies ranging from ionization threshold [11.31 eV; J.C. Traeger, Int. J. Mass...
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Durability of Asphalt Concrete Subjected to Deteriorating Effects of Water and Frost
PublikacjaThe paper presents testing of the detrimental effects of water and frost on asphalt pavements. It included laboratory testing of 5 fatigue life of asphalt concrete that was subjected to action of water and frost and field testing of damages caused by water and frost on 6 existing asphalt pavements, such as stripping, raveling, and potholes. Laboratory simulation of water and frost action was based on the 7 original AASHTO T283...
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Pathogenesis of psoriasis in the “omic” era. Part III. Metabolic disorders, metabolomics, nutrigenomics in psoriasis
PublikacjaPsoriasis is a systemic disease that is strictly connected with metabolic disorders (insulin resistance, atherogenic dyslipidemia, arterial hypertension, and cardiovascular diseases). It occurs more often in patients with a more severe course of the disease. Obesity is specially an independent risk factor and it is associated with a worse treatment outcome because of the high inflammatory activity of visceral fatty tissue and...
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Characterization of GM3 Gangliosides in Human Milk throughout Lactation: Insights from the Analysis with the Use of Reversed-Phase Liquid Chromatography Coupled to Quadrupole Time-Of-Flight Mass Spectrometry
PublikacjaGangliosides are complex lipids found in human milk that play important structural and biological functions. In this study, we utilized reversed-phase liquid chromatography coupled to quadrupole time-of-flight mass spectrometry to evaluate the molecular distribution of GM3 in human milk samples collected at distinct lactation stages, ranging from colostrum to advanced lactation samples. Throughout lactation, GM3 d40:1 emerged as...
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A headspace solid-phase microextraction method development and itsapplication in the determination of volatiles in honeys by gas chromatography
PublikacjaThe first part of the paper presents the detailed optimisation of all steps of the determination procedureof volatiles from Polish honeys by headspace solid-phase microextraction (HS-SPME) as the sample preparationmethod and gas chromatography/mass spectrometry (GC-MS) as the method of final determination.The methodology of semi-quantative analysis allowed the isolation and identification of volatile fractioncompounds from popular...
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Literature update of analytical methods for biogenic amines determination in food and beverages
PublikacjaBiogenic amines (BAs) have been reported in a variety of foods, such as fish, meat, cheese, and wines. The formation of BAs in food by the microbial decarboxylation of amino acids can result in human allergic reactions, characterized by difficulty in breathing, rash, vomiting, and hypertension. Control measures to prevent biogenic amine formation in foods and/or reduce their levels should be considered. Therefore, monitoring of...
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Complementary Use of Multi-dimensional Gas Chromatography and Proton Transfer Reaction Mass Spectrometry for Identification of Rapeseed Oil Quality Indicators
PublikacjaThe change of concentration of various volatiles generated during frying may be an indicator of oil quality. Chemical compounds such as aldehydes, ketones, alcohols and carboxyl acids are the products of oxidation during thermal degradation of edible oils. Shown in this work is a complementary use of GC×GC-TOFMS and PTR-MS for the detection and determination of quality indicators of rapeseed oil. The former technique was used for...
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Aminy w środowisku - niebezpieczeństwo czy jego naturalny element?
PublikacjaA lot of amines and their compounds are used in the industry. First of all they are used for the preparation of medicines, plant protection agents, fertilizers and plastics. Amines are also released into the environment as a result of natural biological processes such as the release of certain species of flowers to lure insects, and also biochemical breakdown of amino acids in the protein during decomposition of organic matter. Unfortunately,...
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Enhanced photocatalytic, electrochemical and photoelectrochemical properties of TiO2 nanotubes arrays modified with Cu, AgCu and Bi nanoparticles obtained via radiolytic reduction
PublikacjaTiO2 nanotubes arrays (NTs), obtained via electrochemical anodization of Ti foil, were modified with monometallic (Cu, Bi) and bimetallic (AgCu) nanoparticles. Different amounts of metals’ precursors were deposited on the surface of NTs by the spin-coating technique, and the reduction of metals was performed via gamma radiolysis. Surface modification of titania was studied by EDS and XPS analysis. The results show that AgCu nanoparticles...
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A Flexible Nafion Coated Enzyme‐free Glucose Sensor Based on Au‐dimpled Ti Structures
PublikacjaThe detection of glucose at low concentrations using electrochemical sensors is of great importance due to the possibility of using different human body fluids than blood, such as e.g. urine, saliva, sweat or tears. The interest behind those biofluids is related to their utility in non-invasive sugar determination. In this work, we present flexible, fully biocompatible electrode material based on Au nanoparticles immobilized onto...
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Cavity-expansion approximation for projectile impact and penetration into sand
PublikacjaA one-dimensional problem of a spherical cavity expanding at a constant velocity from zero initial radius in an infinite granular medium, which has the first-kind self-similar solution, is considered. We are solving this dynamic spherical cavity-expansion problem to model rigid spheres penetrating into a granular media. Elastic–plastic deformation of the granular media is described in a barotropic approximation, using the high-pressure...
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Determination of 3-MCPD and 2-MCPD esters in edible oils, fish oils and lipid fractions of margarines available on Polish market
Publikacja3-monochloropropane-1,2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD) are intensively investigated food contaminants, which recently emerged as a serious problem within the discovery of high levels of their fatty acid esters in lipid samples. In order to monitor the concentrations of mentioned toxicants in edible oils and fats, several analytical methods have been developed so far. This paper presents the screening research...
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Evaluation of Linkers’ Influence on Peptide-Based Piezoelectric Biosensors’ Sensitivity to Aldehydes in the Gas Phase
PublikacjaRecent findings qualified aldehydes as potential biomarkers for disease diagnosis. One of the possibilities is to use electrochemical biosensors in point-of-care (PoC), but these need further development to overcome some limitations. Currently, the primary goal is to enhance their metrological parameters in terms of sensitivity and selectivity. Previous findings indicate that peptide OBPP4 (KLLFDSLTDLKKKMSEC-NH2) is a promising...
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Properties of recombinant trehalose synthase from Deinococcus radiodurans expressed in Escherichia coli
PublikacjaA trehalose synthase gene from Deinococcus radiodurans(DSMZ 20539)containing 1659 bp reading frame encoding 552 amino acids was amplified using PCR. The gene was finally ligated into pET30Ek/LIC vector and expressed after isopropyl β-d-thiogalactopyranoside induction in Escherichia coli (DE3) Rosetta pLysS. The recombinanttrehalose synthase (DraTreS) containing a His6-tag at the C-terminus was purified by metal affinity chromatography...
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Isolation of the GFA1 gene encoding glucosamine-6-phosphate synthase of Sporothrix schenckii and its expression in Saccharomyces cerevisiae
PublikacjaGlucosamine-6-phosphate synthase (GlcN-6-P synthase) is an essential enzyme involved in cell wall biogenesis that has been proposed as a strategic target for antifungal chemotherapy. Here we describe the cloning and functional characterization of Sporothrix schenckii GFA1 gene which was isolated from a genomic library of the fungus. The gene encodes a predicted protein of 708 amino acids that is homologous to GlcN-6-P synthases...
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Ligand-Modified Boron-Doped Diamond Surface: DFT Insights into the Electronic Properties of Biofunctionalization
PublikacjaWith the increasing power of computation systems, theoretical calculations provide a means for quick determination of material properties, laying out a research plan, and lowering material development costs. One of the most common is Density Functional Theory (DFT), which allows us to simulate the structure of chemical molecules or crystals and their interaction. In developing a new generation of biosensors, understanding the nature...
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Bioactive core material for porous load-bearing implants
PublikacjaSo far state of knowledge on biodegradable materials is reviewed. Among a variety of investigated materials, those composed of polymers and ceramics may be considered as only candidates for a core material in porous titanium alloy. The collagen and chitosan among natural polymers, polyhydroxy acids among synthetic polymers, and hydroxyapatite and tricalcium phosphate among ceramics are proposed for further research. Three essential...
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Atom-economic thiophosphoroselenenylations of C–H acid esters and amides
PublikacjaThree improved thiophosphoroselenenylation procedures of CHacids, including derivatives of malonic and acetyl-, phosphono-, 4-nitrophenyl- and 3-pyridylacetic acids, have been described and compared to previously reported thiophosphoroselenylation of diethyl malonate using bis(disopropoxyphosphinothioyl)diselenide alone or with the aid of methyl iodide. The use of iodine makes it possible to utilize both equivalents of the selenenylating...
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One-step recovery of REE oxalates in electro-leaching of spent NdFeB magnets
PublikacjaRecovery of rare-earth elements (REEs) from spent NdFeB magnets is receiving great attention because of high amount of neodymium and potential risk of environmental pollution. In this study, a novel environment-friendly hydrometallurgical route is proposed for efficient recovery of REEs during electrochemical leaching with sulfuric and oxalic acids. With proper adjustment of the electrolyte composition and operating conditions,...
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The biological role of prolyl oligopeptidase and the procognitive potential of its peptidic inhibitors from food proteins
PublikacjaProlyl oligopeptidase (POP) is a conserved serine protease belonging to proline-specific peptidases. It has both enzymatic and non-enzymatic activity and is involved in numerous biological processes in the human body, playing a role in e.g., cellular growth and differentiation, inflammation, as well as the development of some neurodegenerative and neuropsychiatric disorders. This article describes the physiological and pathological...
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Thermodynamics and Intermolecular Interactions of Nicotinamide in Neat and Binary Solutions: Experimental Measurements and COSMO-RS Concentration Dependent Reactions Investigations
PublikacjaIn this study, the temperature-dependent solubility of nicotinamide (niacin) was measured in six neat solvents and five aqueous-organic binary mixtures (methanol, 1,4-dioxane, acetonitrile, DMSO and DMF). It was discovered that the selected set of organic solvents offer all sorts of solvent effects, including co-solvent, synergistic, and anti-solvent features, enabling flexible tuning of niacin solubility. In addition, differential...
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Studies on the solid-liquid equilibria and intermolecular interactions Urea binary mixtures with Sulfanilamide and Sulfacetamide
PublikacjaThe binary phase diagrams of Sulfanilamide-Urea (SN-U) and Sulfacetamide-Urea (SC-U) were measured using differential scanning calorimetry technique (DSC). Both examined mixtures were found to form simple binary eutectics. The limited miscibility in the solid state observed by DSC, proving inability of co-crystallization in new multi-molecular form, was also confirmed using PXRD and FTIR-ATR measurements of solid dispersions...
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Subcritical Thermodynamic Cycles with Organic Medium and Isothermal Expansion
PublikacjaThe efffciencies of the Organic Rankine Cycle (ORC) are not very high and only very seldom do they exceed 20%. The increase and optimization of initial parameters and certain modifications of the thermodynamic cycle make it possible to overcome these drawbacks. A new modified cycle has been described and analyzed in detail in the paper. Similarly to the Ericsson cycle for gas turbines, isothermal expansion in the turbine is suggested...
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Oxygen concentration regulated the efficient liquefaction of vulcanized natural rubber
PublikacjaOxidative liquefaction represents a promising avenue for the homogeneous and high-value utilization of waste tire rubber. Given that truck tires predominantly comprise natural rubber (NR), this study investigated the efficient liquefaction of vulcanized NR regulated by oxygen concentration. Remarkably, the liquefaction of vulcanized NR was realized with an oxygen concentration of 75 % at 200 °C within 3 min. FTIR spectroscopy showed...
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Numerical simulation of temperature distribution of heat flow on reservoir tanks connected in a series
PublikacjaThe flow of temperature distribution through a medium in thermodynamic studies plays an important role in understanding physical phenomena in chemical science and petroleum engineering, while temperature distribution indicates the degree of reaction that must be undergone to obtain the final product. Therefore, this paper aims to present and apply the exponential matrix algorithm (EMA), differential transformation algorithm (DTA),...
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Enhanced acceptor concentration, proton conductivity, and hydration in multicomponent rare‐earth ortho‐niobates
PublikacjaThe structural properties of (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)1−xCaxNbO4−δ (x = 0–0.05) series have been studied by X-ray powder diffraction at room temperature. The thermal properties were investigated using thermogravimetry, from which the concentration of proton defects was determined. Additionally, dilatometry studies were carried out, from which the thermal expansion coefficients and the phase transition temperature between low-...
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Water Solubilization Using Nonionic Surfactants from Renewable Sources in Microemulsion Systems
PublikacjaIn this study the effect of temperature, NaCl andoils (hydrocarbons: C8-C16) on the formation and solubilizationcapacity of the systems of oil/monoacylglycerols(MAG):ethoxylated fatty alcohols (CEO20)/propylene glycol(PG)/water was investigated. The effects of the surfactantmixture on the phase behavior and the concentration ofwater or oil in the systems were studied at three temperatures(50, 55, 60 C) and with varied NaCl solutions...
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Influence of alkaline and oxidative pre-treatment of waste corn cobs on biohydrogen generation efficiency via dark fermentation
PublikacjaStages of waste corn cobs processing leading to the production of biohydrogen via dark fermentation are presented and discussed in this paper. Firstly, the effects of pretreatment conditions i.e. alkaline, alkaline-oxidizing and Fenton oxidizing pre-treatment of lignocellulosic biomass on the removal of lignin were examined. The solid residue obtained in the first stage was subjected to saccharification by means of enzymatic hydrolysis....
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Stability of thin film diamond mirror for applications in interferometers under the short-time exposure on selected aggressive chemicals
PublikacjaIn presented study a thin boron-doped diamond film was proposed for application in the interferometry as a highly durable optical mirror. The unique properties of the diamond films, like high chemical stability and hardness, allow them to be used even in the chemically aggressive environment, where the commonly used silver mirrors can be susceptible to damage. The investigated nanodiamond layer was fabricated by uPE CVD method...
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Isolation of Citrus lemon extracellular vesicles: Development and process control using capillary electrophoresis
PublikacjaA new and scalable method for the isolation of extracellular vesicles (EV) from Citrus lemon juice samples was developed. The methodology included preliminary preconcentration of the sample using ultrafiltration (UF) followed by size-exclusion chromatography (SEC) purification and final preconcentration of the eluates. Transmission electron microscopy and proteomic analysis showed that isolates contained exosome-like vesicles, exocyst-positive...
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Butyrylcholinesterase signal sequence self-aggregates and enhances amyloid fibril formation in vitro
PublikacjaAlzheimer’s disease (AD) pathogenesis has been attributed to extracellular aggregates of amyloid β (Aβ) plaques and neurofibrillary tangles in the human brain. It has been reported that butyrylcholinesterase (BChE) also accumulates in the brain Aβ plaques in AD. We have previously found that the BChE substitution in 5′UTR caused an in-frame N-terminal extension of 41 amino acids of the BChE signal peptide. The resultant variant...
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Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis
PublikacjaEthyl alcohol is the most popular legal drug, but its excessive consumption causes social problems. Despite many public campaigns against alcohol use, car accidents, instances of aggressive behaviour, sexual assaults and deterioration in labor productivity caused by inebriated people is still commonplace. Fast and easy diagnosis of alcohol consumption is required in order to introduce proper and effective therapy, and is crucial...
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The influence of Nigella sativa essential oil on proliferation, activation, and apoptosis of human T lymphocytes in vitro
PublikacjaIn previous work, we tested the immunomodulatory effect of Nigella sativa (NS) fatty oil. Our results demonstrated that unrefined, obtained by cold pressing black cumin seed oil inhibited lymphocytes’ proliferation and induced their apoptosis in a dose-dependent manner. In this study, we examined the immunomodulatory properties of essential oil (EO) obtained from the NS seeds by hydrodistillation and its two main constituents:...
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IN VITRO PROPAGATION OF RHODODENDRON TOMENTOSUM - AN ENDANGERED ESSENTIAL OIL BEARING PLANT FROM PEATLAND
PublikacjaRhododendron tomentosum Harmaja (formerly Ledum palustre L.) is a medicinal peat bog plant native to northern Europe, Asia and North America. This plant has a distinctive aroma thanks to the presence of essential oil, to which it also owes its anti-inflammatory, analgesic, antimicrobial and insecticidal properties. However, in Europe R. tomentosum is classified as an endangered species, mainly due to degradation of peatlands. In...
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Simulations of freshwater lens recharge and salt/freshwater interfaces using the HYDRUS and SWI2 packages for MODFLOW
PublikacjaThe paper presents an evaluation of the combined use of the HYDRUS and SWI2 packages for MODFLOW as a potential tool for modeling recharge in coastal aquife rs subject to saltwater intrusion. The HYDRUS package for MODFLOW solves numerically the one-dimensional form of the Richards equation describing water flow in variably- saturated media. The code computes groundwater recharge to or...
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The role of bile salts in digestion
PublikacjaBile salts (BS) are bio-surfactants present in the gastrointestinal tract (GIT) that play a crucial role in the digestion and absorption of nutrients. The importance of BS for controlled release and transport of lipid soluble nutrients and drugs has recently stimulated scientific interest in these physiological compounds. BS are so-called facial amphiphiles showing a molecular structure that is very distinct from classical surfactants....