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Wyniki wyszukiwania dla: LIPID CONSTITUENTS
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Amphotericin B and Its New Derivatives - Mode of Action
PublikacjaAmphotericin B (AmB) is a well known antifungal and antiprotozoal antibiotic used in the clinic for several decades. Clinicalapplications of AmB, however, are limited by its nephrotoxicity and many other acute side effects which are not acceptable by patientswhen their life is not threaten. In order to improve the therapeutic index of this drug, lipid formulations have been introduced and manyefforts have been made to obtain less...
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Specific Binding of Cholesterol to the Amyloid Precursor Protein: Structure of the Complex and Driving Forces Characterized in Molecular Detail
PublikacjaC99 is the C-terminal membrane-bound fragment of the amyloid precursor protein that is cleaved by γ-secretase to release Aβ peptides, the hallmark of Alzheimer’s disease (AD). Specific interactions of C99 with cholesterol have been proposed to underlie the recognized role of cholesterol in promoting amyloidogenesis. By using molecular dynamics simulations, we studied cholesterol binding to C99 in a lipid bilayer. We determined...
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Health-Promoting Effects of Ethylene-Treated Kiwifruit ‘Hayward’ from Conventional and Organic Crops in Rats Fed an Atherogenic Diet
PublikacjaKiwifruit is a subtropical fruit that is very popular among consumers. Kiwifruit ‘Hayward’ (Actinidia deliciosa C.F. Liang et A.R. Ferguson) is an important source of bioactive compounds and possesses high antioxidant capacity, but its value can be changed during ripening. The aim of this study was to compare the levels of total polyphenols (TP), ascorbic acid (AA), and total antioxidant capacities (TACs) of ethylene-treated and...
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Light-Modulated Sunscreen Mechanism in the Retina of the Human Eye
PublikacjaThe functioning of the human eye in the extreme range of light intensity requires a combination of the high sensitivity of photoreceptors with their photostability. Here, we identify a regulatory mechanism based on dynamic modulation of light absorption by xanthophylls in the retina, realized by reorientation of pigment molecules induced by trans–cis photoisomerization. We explore this photochemically switchable system using chromatographic...
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Badania nad potencjometrycznymi sensorami smaku
PublikacjaPrzedstwiono badania nad 5-kanałowym sensorem smaku kwasnego, zbudowanym z elektrod z membranami polimerowo - lipidowymi zawierającymi odpowiednie lipidy. Stwierdzono, że sensor ten jest bardzo czuły na zmainy stężenia kwasu cytrynowego, natomiast wykazuje nieco gorszą czułosc na obecnosć kwasu octowego. Stwirdzono dobrą trwałosć membran oraz powtarzalnośc otrzymanych wyników. Wydaje się, że badane układy mogą byc wykorzystane...
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Polydopamine Biomaterials for Skin Regeneration
PublikacjaDesigning biomaterials capable of biomimicking wound healing and skin regeneration has been receiving increasing attention recently. Some biopolymers behave similarly to the extracellular matrix (ECM), supporting biointerfacial adhesion and intrinsic cellular interactions. Polydopamine (PDA) is a natural bioadhesive and bioactive polymer that endows high chemical versatility, making it an exciting candidate for a wide range of...
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Time-of-flight electron scattering from molecular hydrogen: Benchmark cross sections for excitation of the X1Σ+g→b3Σ+u transition
PublikacjaThe electron impact X1Σ+g to b3Σ+u transition in molecular hydrogen is one of the most important dissociation pathways to forming atomic hydrogen atoms, and is of great importance in modeling astrophysical and industrial plasmas where molecular hydrogen is a substantial constituent. Recently it has been found that the convergent close-coupling (CCC) cross sections of Zammit et al. [Phys. Rev. A 95, 022708 (2017)] are up to a factor...
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Design and numerical testing of 5-box gfrp shell footbridge
PublikacjaThe paper formulates new design conditions for composite footbridges, taking into account the material and structural specificity of these objects, i.e. the strength condition, the serviceability condition and the frequency condition. A GFRP composite footbridge labelled with CFB2 code has been designed, with the original superstructure in the form of an opened-closed 5-box girder. The foot and cycle track bridge is simply supported,...
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The Thin-Layer Microchromatography (μTLC) and TLC–FID Technique as a New Methodology in the Study of Lubricating Oils
PublikacjaThis paper concerns the possibility of using TLC coupled with a flame ionization detector (FID) and micro-TLC (μTLC) as precursors for microfluidized devices of analytical techniques to identify and determine the presence and content of the petroleum/vegetable oil base in the lubricating oils applied in cutting devices (chainsaws). This research is related to the problem of ensuring, in compliance with the requirements of environmental...
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Deep Eutectic Solvents or Eutectic Mixtures? Characterization of Tetrabutylammonium Bromide and Nonanoic Acid Mixtures
PublikacjaDeep eutectic solvents have quickly attracted the attention of researchers because they better meet the requirements of green chemistry and thus have the potential to replace conventional hazardous organic solvents in some areas. To better understand the nature of these mixtures, as well as expand the possibilities of their use in different industries, a detailed examination of their physical properties, such as density, viscosity,...
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Etyka - o konieczności dyskursu etycznego w organizacjach
PublikacjaDo budowania zasad dobrego funkcjonowania organizacji, do odkrywania mechanizmów jej funkcjonowania, analizowania ludzkich potrzeb i możliwości ich realizowania, do wpływu warunków ekonomicznych i kulturowych na sposób funkcjonowania organizacji – do tych problemów przywiązuje się wielką wagę w naukach o zarządzaniu. Czy równie dużą wagę przykłada się – i docenia – rangę zachowań ludzkich w sferze moralnej, wpływ zasad etycznych...
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Factors Affecting the Rheological Properties of Foods
PublikacjaIn this chapter, engineering aspects concerning real body mechanics and the impact of respective food ingredients on said properties are presented together. Food is a complex matrix and each of macro and micro ingredients plays its role in the formation of rheologic properties, and minor changes in the basic ingredient structure may affect the change of these properties significantly. Basic analytic techniques are presented for...
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Anomalous Behavior of Hyaluronan Crosslinking Due to the Presence of Excess Phospholipids in the Articular Cartilage System of Osteoarthritis
PublikacjaLubrication of articular cartilage is a complex multiscale phenomenon in synovial joint organ systems. In these systems, synovial fluid properties result from synergistic interactions between a variety of molecular constituent. Two molecular classes in particular are of importance in understanding lubrication mechanisms: hyaluronic acid and phospholipids. The purpose of this study is to evaluate interactions between hyaluronic acid...
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Government in the metaverse: Requirements and suitability for providing digital public services
PublikacjaDigital government comprises all means to enable governments to interact with their constituents digitally. The metaverse provides a virtual reality environment where various activities can be carried out without physically visiting the places of interest, including the public authorities. Yet, how governments can use the metaverse is unknown. This paper aims to extend the understanding of the metaverse architecture requirements...
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Study of pH and temperature effect on lipophilicity of catechol-containing antioxidants by reversed phase liquid chromatography
PublikacjaLipophilicity of selected antioxidant phytochemicals, including flavonoids, phenolic acids and xanthonoids, was determined by reversed phase high performance liquid chromatography with UV detection (RP-HPLC-UV). The analyses run at different temperature and pH conditions in isocratic mode suggested that lipophilicity as distribution coefficient (logD) between aqueous and organic phase decreases with increasing temperature. For...
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Deep eutectic solvents – Ideal solution for clean air or hidden danger?
PublikacjaThe industrial sector is one of the fastest-growing sources of greenhouse gases, due to its excessive energy consumption to meet the rapidly growing demand for energy-intensive products. The use of deep eutectic solvents (DESs) has been studied extensively in order to cope with these harmful gases, but their usage can be an issue in respect to ecological reasons. Do deep eutectic solvents harm the atmosphere? Yes, these solvents...
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Antitumor DNA-Damaging C-1748 is a New Inhibitor of Autophagy that Triggers Apoptosis in Human Pancreatic Cancer Cell Lines
PublikacjaDespite the enormous progress that has been made over the past decades in diagnosis, treatment and prevention of many types of tumors, survival rates in pancreatic cancer still remain poor. Pancreatic cancer is one of the most malignant and chemoresistant tumors and the profound mechanism supporting these phenomena is the constitutively activated prosurvival autophagy. The antitumor 1-nitroacridine derivative C-1748 belongs to...
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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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Energetics of formation and stability in high pressure steam of barium lanthanide cobaltite double perovskites
PublikacjaThis study concerns energetics of formation and the stability in high water partial pressure of BaLnCo2O6−δ, (Ln = La, Pr, Nd, and Gd) (BLnC) and BaGd1−xLaxCo2O6−δ, where x = 0.2, 0.5, and 0.7 (BGLC) double perovskite cobaltites. Those materials are extensively studied due to their potential applications as a positrode in electrochemical devices. Therefore, their stability under such conditions is a key issue. All investigated...
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Structured triacylglicerols containing behenic acid: preparation and properties
PublikacjaNiskokaloryczne lipidy strukturyzowane otrzymano na drodze przeestryfikowania właściwego oleju oliwkowego całkowicie uwodornionym wysokoerukowym olejem rzepakowym (TAG/SLHE) oraz na drodze acydolizy oleju oliwkowego kwasem behenowym (TAG/SLB). Reakcje były katalizowane Lipozyme RM IM. Tłuszcz (TAG/SLHE) charakteryzował się wysoką temperaturą topnienia - 45,5 st. C, natomiast tłuszcz (TAG/SLB) miał temperaturę topnienia 37,5 st.C...
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Application of human bile salts for in vitro digestion models
PublikacjaIn this study, experimental in vitro models simulating the environment of the human gastrointestinal tract were used to assess the impact of physiological surfactants, such as bile salts, on the kinetics of digestion. Bile salts are biosurfactants synthesised in the liver and secreted together with bile into the small intestine. There are many reports on the role of bile salts in lipolysis, but the knowledge of their influence...
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Analiza porównawcza struktury zalążka u Sedum hispanicum L. i Sedum acre L.
PublikacjaZalążki Sedum hispanicum i S. acre ze względu na budowę klasyfikuje się jako anatropowe. Rozwój zarodka przebiega według typu Caryophyllad - po podziale zygoty powstają dwie komórki, komórka bazalna, która nie ulega podziałom oraz komórka apikalna, z której powstaje cały zarodek właściwy i chalazalne komórki suspensora. Przez cały okres rozwoju zalążka odżywianie zarodka przechodzi od stadium pobierania substancji odżywczych za...
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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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Corporate social responsibility and forward default risk mediated by financial performance and goodwill
PublikacjaIn today’s business environment, corporate social responsibility (CSR) has become an increasingly significant factor for firms. This study is driven by the motivation to add to the current literature by investigating the mediating elements that explain the relationship between CSR and forward default risk. In this paper, we attempt to identify the important mediators and give a more comprehensive explanation of this connection...
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AGREEMIP: The Analytical Greenness Assessment Tool for Molecularly Imprinted Polymers Synthesis
PublikacjaMolecular imprinting technology is well established in areas where a high selectivity is required, such as catalysis, sensing, and separations/sample preparation. However, according to the Principles of Green Chemistry, it is evident that the various steps required to obtain molecularly imprinted polymers (MIPs) are far from ideal. In this regard, greener alternatives to the synthesis of MIPs have been proposed in recent years....
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Noise in biological Raman spectroscopy
PublikacjaRaman spectroscopy is a widely used method to investigate chemical molecules by analyzing their vibrational transitions. It utilizes inelastic scattering of the laser light irradiating the investigated object. The scattered light requires appropriate filtering to reduce dominant laser light and expose much weaker components having shifted wavelengths of a characteristic spectral pattern. These components are measured by dispersing...
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Human serum interactions with phenolic and aroma substances of Kaffir(Citrus hystrix) and Key lime (Citrus aurantifolia) juices
PublikacjaTo understand the therapeutic application of polyphenols extracted from Kaffir (PolKaf) and Key (PolKey) limesdifferent analytical methods were applied. Based on quantitative analysis by two dimensional gas chromato-graphy (GC×GC) and time of flight mass spectrometry (TOFMS) it can be observed that the biggest differencesin the contents of selected terpenes of Kaffir and Key limes occur in chemical compounds such as limonene, citraland...
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Impedimetric sensing of α-amino acids driven by micro-patterned 1,8-Diazafluoren-9-one into titania- boron- doped maze-like nanocarbons
PublikacjaThe development of impedimetric, non-faradaic label-free sensors for the detection of α-amino acids constitutes a trailblazing technology for the fast and inexpensive quantification of such biomarkers. Since α-amino acids, such as glycine and sarcosine, are basic constituents in biological processes, a variation in their concentration may be an indicator of cardiovascular diseases and metabolic disorders or neurological conditions....
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Which casein in sodium caseinate is most resistant to in vitro digestion? Effect of emulsification and enzymatic structuring
PublikacjaWe investigated the resistance of individual constituent casein epitopes (αS1-, αS2-, β- and κ-CN) in food-grademilk protein sodium caseinate (NaCN) to simulated human gastro-duodenal digestion. The influence of NaCNadsorption to the surface of oil-in-water emulsion droplets and the effect of crosslinking of the protein withenzyme transglutaminase (TG) on the proteolysis were studied by indirect ELISA. TG crosslinking renderedfragments...
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Metal tolerance and Cd phytoremoval ability in Pisum sativum grown in spiked nutrient solution
PublikacjaIn the presented study, the effects of cadmium (Cd) stress and silicon (Si) supplementation on the pea plant (Pisum sativum L.) were investigated. The tendency to accumulate cadmium in the relevant morphological parts of the plant (roots and shoots respectively)—bioaccumulation, the transfer of this element in the plant (translocation) and the physiological parameters of the plant through...
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Viability of fruit seed oil O/W emulsions in personal care products
PublikacjaThe use of fruit seed oils in personal care products is of significance to both their function and image. Poland is an important processor of fruit products within the EU, and thus has a large availability of seeds from domestic fruits, which are normally considered to be a waste material or feed for livestock. Unfortunately, current literature is scarce of the suitability of these oils for topical dermatological use in the form...
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Comparative Study of Taste Substance Sensing by Liquid Membrane Oscillator and Electrochemical Systems With All-Solid-State Electrodes
PublikacjaIn food industry, different types of sensors are used for characterizing and quantifying taste substances. Therefore, it is important to establish the principal advantages and disadvantages of these sensors for optimal application. In this paper, two possible systems are compared for sensing the four fundamental tastes: sour (citric acid), salty (sodium chloride), sweet (sucrose), and bitter (caffeine or quinine hydrochloride). One...
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How do sterols determine the antufungal activitiy of amphotericin B? Free energy of binding between the drug and its membrane targets.
PublikacjaAmphotericin B (AmB) is a well-known polyene antibiotic used to treat systemic fungal infections. It is commonly accepted that the presence of sterols in the membrane is essential for the AmB biological activity, that is, for the formation of transmembrane ion channels. The selective toxicity of AmB for fungal cells is attributed to the fact that it is more potent against fungal cell membranes containing ergosterol than against...
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Classification of submandibular salivary stones based on ultrastructural studies
PublikacjaIntroduction: Sialolithiasis remains a clinical problem with unclear etiopathogenesis, lack of prevention methods, and only surgical treatment. Materials and methods: An ultrastructure examination of submandibular sialoliths obtained from patients with chronic sialolithiasis was conducted using a scanning electron microscope and X‐ray photoelectron spectroscopy. Results: Based on the results, we divided sialoliths into three types:...
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Naturalne związki organiczne.
PublikacjaNowoczesny podręcznik stanowiący kompendium podstawowych wiadomości o najważniejszych naturalnych związkach organicznych, takich jak: aminokwasy, peptydy, białka, cukry, lipidy, alkaloidy, steroidy, terpeny i terpenoidy. Omówono w nim właściwości chemiczne i fizyczne, działanie fizjologiczne oraz otrzymywanie i zastosowanie tych związków. Przedstawiono również najnowszeosiągnięcia naukowe dotyczące produktów naturalnych, m.in....
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Naturalne związki organiczne
PublikacjaNowoczesny podręcznik stanowiący kompendium podstawowych wiadomości o najważniejszych naturalnych związkach organicznych, takich jak: aminokwasy, peptydy, białka, cukry, lipidy, alkaloidy, steroidy, terpeny i terpenoidy. Omówiono w nim właściwości chemiczne i fizyczne, działanie fizjologiczne oraz otrzymywanie i zastosowanie tych związków. Przedstawiono również najnowsze osiągnięcia naukowe dotyczące produktów naturalnych, m.in....
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The role of centrifugal partition chromatography in the removal of β-asarone from Acorus calamus essential oil
PublikacjaΒ-asarone is a phenylpropane derivative present in the rhizomes of Acorus calamus, that was proved to exhibit toxic effects in humans. Because of its presence the whole plant that is commonly used in traditional medicine for its sedative, anti-inflammatory, neuroprotective and other properties has limited application nowadays. In the study, qualitative and quantitative analysis of a collection of nine essential oil (EO) samples...
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Antibiotic-sterol interactions provide insight into the selectivity of natural aromatic analogues of amphotericin B and their photoisomers
PublikacjaAromatic heptaene macrolides (AHMs) belong to the group of polyene macrolide antifungal antibiotics. Members of this group were the first to be used in the treatment of systemic fungal infections. Amphotericin B (AmB), a non-aromatic representative of heptaene macrolides, is of significant clinical importance in the treatment of internal mycoses. It includes the all-trans heptaene chromophore, whereas the native AHMs contain two...
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Regulated Assembly of LPS, Its Structural Alterations and Cellular Response to LPS Defects
PublikacjaDistinguishing feature of the outer membrane (OM) of Gram-negative bacteria is its asymmetry due to the presence of lipopolysaccharide (LPS) in the outer leaflet of the OM and phospholipids in the inner leaflet. Recent studies have revealed the existence of regulatory controls that ensure a balanced biosynthesis of LPS and phospholipids, both of which are essential for bacterial viability. LPS provides the essential permeability...
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Reducing Monitoring Costs in Industrially Contaminated Rivers: Cluster and Regression Analysis Approach
PublikacjaMonitoring contamination in river water is an expensive procedure, particularly for developing countries where pollution is a significant problem. This study was conducted to provide a pollution monitoring strategy that reduces the cost of laboratory analysis. The new monitoring strategy was designed as a result of cluster and regression analysis on field data collected from an industrially influenced river. Pollution sources in...
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Bioaccumulation of Metals in Tissues of Marine Animals, Part I: the Role and Impact of Heavy Metals on Organisms
PublikacjaHeavy metals contribute to the anthropogenic contamination of marine ecosystems. Some of them are essential to the life processes of organisms; others are toxic, even at low concentrations. They penetrate organisms via food, respiratory pathways or the skin. The extent to which metals penetrate organisms is measured by the bioconcentration and bioaccumulation factors and also by their transport between organisms at different trophic...
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Release of selected chemical elements from shale drill cuttings to aqueous solutions of different pH
PublikacjaThe effect of pH changes on leachability of light and heavy metals from shale drill cuttings generated from unconventional shale gas production was investigated. Cuttings, being the primary byproduct generated from drilling operations, belong to the potentially hazardous type of wastes due to presence of heavy and radioactive elements and remains of drilling fluid. In this regard, assessment of potentially dangerous components...
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Implementation of Hermite-Ritz method and Navier’s Technique for Vibration of Functionally Graded Porous Nanobeam Embedded in Winkler-Pasternak Elastic Foundation Using bi-Helmholtz type of nonlocal elasticity
PublikacjaPresent study is devoted to investigating the vibration characteristics of Functionally Graded (FG) porous nanobeam embedded in an elastic substrate of Winkler-Pasternak type. Classical beam theory (CBT) or Euler-Bernoulli beam theory (EBT) has been incorporated to address the displacement of the FG nanobeam. Bi-Helmholtz type of nonlocal elasticity is being used to capture the small scale effect of the FG nanobeam. Further, the...
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NEW EXPERIENCES IN DIKE CONSTRUCTION WITH SOIL-ASH COMPOSITESAND FINE-GRAINED DREDGED MATERIALS
PublikacjaThe supporting structure inside a coastal dike is often made of dredged non-uniform sand with good compaction proper-ties. Due to the shortage of natural construction material for both coastal and river dikes and the surplus of different processed mate-rials, new experiments were made with sand-ash mixtures and fine-grained dredged materials to replace both dike core and dikecover materials resulting in economical, environmentally...
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Recent progress in ultra-low formaldehyde emitting adhesive systems and formaldehyde scavengers in wood-based panels: a review
PublikacjaTraditional wood-based panels are produced with synthetic, formaldehyde-based adhesives, commonly made from fossil-derived constituents, such as urea, phenol, melamine, etc. Along with their numerous advantages, such as chemical versatility, high reactivity and excellent adhesive performance, these adhesives are characterized by certain problems, connected with the hazardous volatile organic compounds (VOCs), mostly free formaldehyde...
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Production of essential oils from in vitro cultures of Caryopteris species and comparison of their concentrations with in vivo plants
PublikacjaThe chemical composition of hydrodistilled essential oils obtained from aerial parts and roots of selected Caryopteris (‘bluebeard’) species (C. incana, C. mongolica, Caryopteris 9 clandonensis), as well as the newly established in vitro shoot and adventitious root cultures of the above plants, was analyzed by gas chromatography– mass spectrometry. Essential oil content and composition differed significantly depending on the type...
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Communication: Inside the water wheel: Intrinsic differences between hydrated tetraphenylphosphonium and tetraphenylborate ions
PublikacjaTetraphenylphosphonium tetraphenylborate (TPTB) is a common reference electrolyte in physical chemistry of solutions allowing for a convenient partitioning of thermodynamic properties into single-ion contributions. Here, we compute on the basis of ab initio molecular dynamics simulations the infrared (IR) spectra for hydrated constituent ions of the TPTB assumption. Using spectral decomposition techniques, we extract important...
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Classification of submandibular salivary stones based on ultrastructural studies
PublikacjaIntroduction: Sialolithiasis remains a clinical problem with unclear etiopathogenesis, lack of prevention methods, and only surgical treatment. Materials and methods: An ultrastructure examination of submandibular sialoliths obtained from patients with chronic sialolithiasis was conducted using a scanning electron microscope and X-ray photoelectron...
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Molecular and structural basis of inner core lipopolysaccharide alterations in Escherichia coli: incorporation of glucuronic acid and phosphoethanolamine in the heptose region.
PublikacjaIt is well established that lipopolysaccharide (LPS) often carries nonstoichiometric substitutions in lipid A and in the inner core. In this work, the molecular basis of inner core alterations and their physiological significance are addressed. A new inner core modification of LPS is described, which arises due to the addition of glucuronic acid on the third heptose with a concomitant loss of phosphate on the second heptose. This...
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Assessment of Electronic Sensing Techniques for the Rapid Identification of Alveolar Echinococcosis through Exhaled Breath Analysis
PublikacjaHere we present a proof-of-concept study showing the potential of a chemical gas sensors system to identify the patients with alveolar echinococcosis disease through exhaled breath analysis. The sensors system employed comprised an array of three commercial gas sensors and a custom gas sensor based on WO3 nanowires doped with gold nanoparticles, optimized for the measurement of common breath volatile organic compounds. The measurement...