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A magnetic stir bar sorbent of metal organic frameworks, carbon foam decorated zinc oxide and cryogel to enrich and extract parabens and bisphenols from food samples
PublicationA porous composite magnetic stir bar adsorbent was fabricated for the extraction and enrichment of parabens and bisphenols from selected beverage samples. The adsorbent comprised a metal organic framework, carbon foam decorated zinc oxide and magnetic nanoparticles embedded in polyvinyl alcohol cryogel. The porous composite stir bar adsorbent could adsorb parabens and bisphenols via hydrogen bonding, π-π and hydrophobic interactions....
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Sensitive method for determination of benzoic acid in beverages and food samples using air–assisted hydrophobic deep eutectic solvent-based dispersive liquid-liquid microextraction
PublicationA simple, reliable and rapid air–assisted hydrophobic deep eutectic solvent-based dispersive liquid–liquid microextraction (AA-HDES-DLLME) was developed for analysis of benzoic acid in various beverages and food samples. The final determination stage was performed via UV–visible spectrophotometry. The key parameters (extraction time, HDES type and volume, dispersant volume, pH and sample volume) of the AA-HDES-DLLME method were...
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A New Expression System Based on Psychrotolerant Debaryomyces macquariensis Yeast and Its Application to the Production of Cold-Active β-D-Galactosidase from Paracoccus sp. 32d
PublicationYeasts provide attractive host/vector systems for heterologous gene expression. The currently used yeast-based expression platforms include mesophilic and thermotolerant species. A eukaryotic expression system working at low temperatures could be particularly useful for the production of thermolabile proteins and proteins that tend to form insoluble aggregates. For this purpose, an expression system based on an Antarctic psychrotolerant...
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In Situ Random Microseeding and Streak Seeding Used for Growth of Crystals of Cold-Adapted beta-D-Galactosidases: Crystal Structure of betaDG from Arthrobacter sp. 32cB
PublicationThere is an increasing demand for cold-adapted enzymes in a wide range of industrial branches. Nevertheless, structural information about them is still scarce. The knowledge of crystal structures is important to understand their mode of action and to design genetically engineered enzymes with enhanced activity. The most difficult task and the limiting step in structural studies of cold-adapted enzymes is their crystallization,...
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Module structure in Conley theory with some applications
PublicationA multiplicative structure in the cohomological versjon of Conley index is described . In the case of equivariant flows we apply the normalization procedure known from equivariant degree theory and we propose a new continuation invariant. The theory is then applied to obtain a mountain pass type theorem. Another application is a result on multiple bifurcations for some elliptic PDE.
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Analysis of a gene expression model
PublicationWe study a mathematical model of gene transcription and protein synthesis with negative feedback. We consider a system of equations taking into account the number of active binding sites, the way in which dimers bind to DNA and time delay in translation process. For a simplified model that consist of three ordinary differential equations with time delay we derive conditions for stability of the positive steady state and for the...
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Journal of Food Measurement and Characterization
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Emirates Journal of Food and Agriculture
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Visualizing Carotid Bodies With Doppler Ultrasound Versus CT Angiography: Preliminary Study
PublicationOBJECTIVE. The purpose of this article is to evaluate the utility of ultrasound in identifying carotid bodies (CBs) in patients with drug-resistant arterial hypertension. SUBJECTS AND METHODS. We enrolled 13 patients with drug-resistant hypertension into a trial for surgical CB excision. CT angiography (CTA) and Doppler ultrasound (DUS) of the cervical arteries were performed before surgery. CBs were identified in a blind manner...
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ANTHROPOGENIC CHANGES OF THE “OLD COPPER BASIN” AREA LANDSCAPE (NORTH-SUDETIC SYNCLINORIUM) IN THE LIGHT OF LIDAR-BASED GEOMORPHOMETRIC ANALYSIS AND ARCHIVAL DATA
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FOOD POLICY
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Food OxNA2 Assessment of the potential toxicological risk associated with the consumption of nucleic acids oxidized during thermal processing of meat products
ProjectsProject realized in Department of Chemistry, Technology and Biochemistry of Food according to UMO-2023/49/N/NZ9/02749 agreement
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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublicationA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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Dispersive Micro‐Solid Phase Extraction of Selected Metals in Water and Food Samples Followed by ICP‐OES Analysis: Method Development, Analysis of Real Samples and Greenness Evaluation
PublicationMultiwalled carbon nanotubes (MWCNTs) are well-known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro-solid-phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the...
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Macro-nutrients recovery from liquid waste as a sustainable resource for production of recovered mineral fertilizer: Uncovering alternative options to sustain global food security cost-effectively
PublicationGlobal food security, which has emerged as one of the sustainability challenges, impacts every country. As food cannot be generated without involving nutrients, research has intensified recently to recover unused nutrients from waste streams. As a finite resource, phosphorus (P) is largely wasted. This work critically reviews the technical applicability of various water technologies to recover macro-nutrients such as P, N, and...
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Performance of electrochemical immunoassays for clinical diagnostics of SARS-CoV-2 based on selective nucleocapsid N protein detection: Boron-doped diamond, gold and glassy carbon evaluation
PublicationThe 21st century has already brought us a plethora of new threats related to viruses that emerge in humans after zoonotic transmission or drastically change their geographic distribution or prevalence. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first spotted at the end of 2019 to rapidly spread in southwest Asia and later cause a global pandemic, which paralyzes the world since then. We have designed novel...
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Mathematical analysis of a generalised p53-Mdm2 protein gene expression model
PublicationWe propose the generalisation of the p53-Mdm2 protein gene expression model introduced by Monk (2003). We investigate the stability of a unique positive steady state and formulate conditions which guarantee the occurrence of the Hopf bifurcation. We show that oscillatory behaviour can be caused not only by time lag in protein transcription process, but also can be present in the model without time delay. Moreover, we investigate...
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Jacek Tomków dr hab. inż.
PeopleEducation:1. 2018 - Ph.D. of Technical Sciencesin field of Materials Engineeringthesis: Influence of underwater welding conditions on cold cracking of high strength low alloy steel 2. 2012 - Master of Science Engineer, Gdansk University of Technologyin the field of: Mechanical Engineeringwith specialization in: Manufacturing Engineering and Computer Aided Manufacturing Processesthesis: Non-destructive testing of welding joints...
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VETERINARY CLINICS OF NORTH AMERICA-FOOD ANIMAL PRACTICE
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Global Food Security-Agriculture Policy Economics and Environment
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Food, Culture and Society: An International Journal of Multidisciplinary Research
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Locale-The Australian-Pacific Journal of Regional Food Studies
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Acta Universitatis Cibiniensis - Series E: Food Technology
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Canrea Journal: Food Technology, Nutritions, and Culinary Journal
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Bistability in a One-Dimensional Model of a Two-Predators-One-Prey Population Dynamics System
PublicationIn this paper, we study a classical two-predators-one-prey model. The classical model described by a system of three ordinary differential equations can be reduced to a one-dimensional bimodalmap. We prove that this map has at most two stable periodic orbits. Besides, we describe the bifurcation structure of the map. Finally, we describe a mechanism that leads to bistable regimes. Taking this mechanism into account, one can easily...
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Coupling of cold vapor generation with an atmospheric pressure glow microdischarge sustained between a miniature flow helium jet and a flowing liquid cathode for the determination of mercury by optical emission spectrometry
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Application of gas flow headspace liquid phase micro extraction coupled with gas chromatography-mass spectrometry for determination of 4-methylimidazole in food samples employing experimental design optimization
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The Mesoporous Porphyrinic Zirconium Metal-Organic Framework for Pipette-Tip Solid-Phase Extraction of Mercury from Fish Samples Followed by Cold Vapor Atomic Absorption Spectrometric Determination
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Magnetic hydrophobic deep eutectic solvents for orbital shaker-assisted dispersive liquid-liquid microextraction (MAGDES-OS-DLLME) - determination of nickel and copper in food and water samples by FAAS
PublicationIn this work, a cheap and widely applicable dispersive liquid-liquid microextraction (DLLME) method was developed for the extraction of Ni(II) and Cu(II) from water and food samples and analysis using flame atomic absorption spectrometry. DLLME was assisted by orbital shaker, while ferrofluid as an extractant was based on deep eutectic solvent (DES). This ferrofluid was made of hydrophobic DES (hDES), composed of lauric acid and...
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Orthodontic characteristics of maxillary arch deficiency in 5-year-old patients undergoing unilateral cleft lip and palate repair with and without early gingivoplasty
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CHILDRENS GEOLOGY. 6, 7 AND 8 YEAR-OLD CHILDRENS UNDERSTANDING OF THE PHENOMENA OF VOLCANIC EXPLOSION, MOUNTAINS FORMATION AND ACCUMULATION OF SNOW ON MOUNTAIN PEAKS
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Możliwość zmniejszenia zanieczyszczeń pyłami i gazami podczas przecinania ściernicowego.
PublicationDwie możliwości istotnego zmniejszania zanieczyszczeń środowiska naturalnego pyłami, metalami i gazami w procesie przecinania ściernicowego. Do możliwości tych należą: zmiana technologii wykonania ściernicy, zastosowanie specjalnego pochłaniacza zanieczyszczeń. Dokonano analizy porównawczej trzech rodzajów zanieczyszczeń przy wykorzystaniu obydwu możliwości ich zmniejszenia.
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Technological effect comparison of abrasive and plastic working. Production Processes and Systems**2002 vol. 1 s. 89-98, 9 rys. 2 tabl. bibliogr. 6 poz Publication of the University of Miskolc. Porównanie technologicznych efektów obróbki ściernej i plastycznej.
PublicationPrzedstawiono wyniki badań porównawczych próbek obrobionych wykańczająco przez szlifowanie i docieranie oraz przez powierzchniową obróbkę plastyczną przez nagniatanie ślizgowe. Podano także konstrukcje narzędzi i przykłady stosowania badanych metod obróbki.
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Planläppen mit Schleif-Metall Läppscheibe von flachen Oberflächen.
PublicationPrzedstawiono wyniki badań docierania powierzchni płaskich narzędziami ścierno-metalowymi. Analizowano wpływ warunków obróbki na wydajność i jakość powierzchni elementów ceramicznych tlenkowych.
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Die Perspektiven der weiteren Anwendung des Trennschleifens
PublicationW referacie przedstawiono wyniki prac doświadczalnych nad efektywnością technologiczną przecinania ściernicowego w głównych jej aspektach: chropowatości powierzchni, przypaleń, tolerancji długości ciecia.
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COMPOSITION OF BIOACTIVE SECONDARY METABOLITES AND MUTAGENICITY OF SAMBUCUS NIGRA L. FRUIT AT DIFFERENT STAGES OF RIPENESS
PublicationThe relationship between the content of bioactive compounds and mutagenic activity of elderberry fruit at different stages of ripeness was investigated. Signifi cant differences in the antioxidant profi les (TLC, HPLC with post-column derivatization) and antioxidant activity (ABTS, DPPH, and FC tests) were observed for studied elderberry extracts. The more ripen the fruit at the time of harvest were, the higher the content of...
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Energy, water detailed usage. Living lab testing for sustainable urban food-water-energy cycle. Jan. 2022
Open Research DataData set contains detailed, continuous measurements of the usage of water and electrical energy (AC power) in an experimental facility set up in a scientific laboratory (Laboratorium im. B.Niemkiewicza) at the Faculty of Mechanical Engineering and Ocean Technology of the Gdansk University of Technology. The test bed was established in co-operation...
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Energy, water detailed usage. Living lab testing for sustainable urban food-water-energy cycle. Dec. 2021
Open Research DataData set contains detailed, continuous measurements of the usage of water and electrical energy (AC power) in an experimental facility set up in a scientific laboratory (Laboratorium im. B.Niemkiewicza) at the Faculty of Mechanical Engineering and Ocean Technology of the Gdansk University of Technology. The test bed was established in co-operation...
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Topological Behaviour of Solutions of Vibro-Impact Systems in the Neighborhood of Grazing
PublicationThe grazing bifurcation is considered for the Newtonian model of vibro-impact systems. A brief review on the conditions, sufficient for the existence of a grazing family of periodic solutions, is given. The properties of these periodic solutions are discussed. A plenty of results on the topological structure of attractors of vibro-impact systems is known. However, since the considered system is strongly nonlinear, these attractors...
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Identyfikacja i izolacja genu kodującego zaadaptowaną do zimna β-galaktozydazę Paracoccus sp. = Identification and izolation of the gene encoding cold-active β-galactosidase from paracoccus sp.
PublicationZaprezentowane badania były prowadzone u eehi wyizolowania ze środo¬wiska organizmu psychrofilnego, zdolnego do hydrolizy laktozy w niskiej tempe¬raturze, oraz zidentyfikowania genu kodującego (i-galaktozydazę zaadaptowaną do zimna.Poszukiwan gen został w izolowany z psychrofilnego szczepu autarkicz¬nego Paracoccus sp. 321). Na podstawie sekwencji nukleotydowej genu kodują¬cego fS-galaktozdaze ustalono skład aminokwasów),...
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Salinity enhances high optically active L-lactate production from co-fermentation of food waste and waste activated sludge: Unveiling the response of microbial community shift and functional profiling
PublicationLactic acid (LA), a versatile platform molecule, can be fermented from organic wastes, such as food waste and waste activated sludge. In this study, an efficient approach using salt, a component of food waste as an additive, was proposed to increase LA production. The LA productivity was increased at 10 g NaCl/L and optical pure L-lactate was obtained at 30 g NaCl/L. The enhancement of LA was in accordance with the increased solubilization...
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Michał Lech dr inż.
PeopleMichał Lech was born in Gdynia in 1983. In 2007 he graduated from the faculty of Electronics, Telecommunications and Informatics of Gdansk University of Technology. In June 2013, he received his Ph.D. degree. The subject of the dissertation was: “A Method and Algorithms for Controlling the Sound Mixing Processes by Hand Gestures Recognized Using Computer Vision”. The main focus of the thesis was the bias of audio perception caused...
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Application of gas chromatography,mass spectrometry and olfactometry for quality assessment of selected food products = Zastosowanie chromatografii gazowej, spektrometrii mas i olfaktometrii w ocenie jakości wybranych produktów spożywczych
PublicationStosując mikroekstrakcję do fazy stacjonarnej z fazy nadpowierzchniowej jako metodę przygotowania próbek i chromatografię gazową (GC) ze spektrometrią mas (MS) i olfaktometrią (O) jako metodę oznaczeń końcowych oznaczono lotne związki w spirytusach i miodach. Identyfikację przeprowadzono przez porównanie widm masowych z widmami z biblioteki NIST. Dodatkowo, wykrywane przez panel oceniający związki zapachowe rejestrowano w formie...
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The Influence of Cold Atmospheric Pressure Plasma-Treated Media on the Cell Viability, Motility, and Induction of Apoptosis in Human Non-Metastatic (MCF7) and Metastatic (MDA-MB-231) Breast Cancer Cell Lines
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Paweł Filipkowski dr inż.
PeoplePaweł Filipkowski Ph.D. Biotechnology Department of Chemistry, Technology and Biotechnology of Food Faculty of Chemistry Gdansk University of Technology Narutowicza 11/12 80-233 Gdansk, Poland Tel: +48 58 3472456 e-mail: pawel.filipkowskiATpg.edu.pl Current position: Assistant Professor/Senior Lecturer*(from Jan.2019) of Biotechnology, Department of Chemistry, Technology and Biotechnology of Food, Gdansk University of Technology. Education: Eng....
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PANTOGRAPH AS AN EXAMPLE OF THE USE OF GEOMETRIC TRANSFORMATIONS IN CONSTRUCTING OF OLD DRAWING INSTRUMENTS = PANTOGRAF JAKO PRZYKŁAD ZASTOSOWANIA PRZEKSZTAŁCEŃ GEOMETRYCZNYCH W KONSTRUOWANIU DAWNYCH PRZYRZĄDÓW KREŚLARSKICH
PublicationThe article describes the pantograph, considered to be the ancestor of today's photocopier. This instrument draws the copies, enlarges or reduces any figure. The author presents its genesis, the scope of application in the past, explains the structure and geometrical transformations used during its action. Based on a specific example, the work illustrates practical application of geometry in the past inventions for designing.
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Porównanie technik oczyszczania ekstraktów z żywności zawierającej pestycydy chloroorganiczne oraz anality z grupy PCB = The comparison of techniques for the clean-up of food extracts containing organochlorine pesticides and polychlorinated biphenyls
PublicationW pracy przedstawiono wyniki badań dotyczących opracowania metody oczyszczania ekstraktów z żywności o zawartości tłuszczu od 10 do 13% opartej na technice ekstrakcji do fazy stałej przy jakościowym i ilościowym oznaczaniu związków chloroorganicznych. W tym celu porównano odzyski wybranych analitów chloroorganicznych w przypadku zastosowania różnych rozpuszczalników na etapie izolacji analitów z matrycy oraz w przypadku oczyszczania...
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The psychrotrophic yeast Sporobolomyces roseus LOCK 1119 as a source of a highly active aspartic protease for the in vitro production of antioxidant peptides
PublicationA psychrotrophic yeast strain producing a cold-adapted protease at low temperature was classified as Sporobolomyces roseus. In standard YPG medium, S. roseus LOCK 1119 synthesized an extracellular protease with an activity of approximately 560 U/L. Optimization of medium composition and process temperature considerably enhanced enzyme biosynthesis; an approximate 70% increase in activity (2060 U/L). The native enzyme was purified...
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Początki piśmiennictwa staropermskiego. Stefanowski anbur jako jeden z najstarszych zabytków uralskich [The beginnings of Old Permian writings. Anbur (abur) as one of the oldest Uralian scripts]
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SCIENTIFIC WORKS NATIONAL UNIVERSITY of FOOD TECHNOLOGIES SCIENTIFIC WORKS NATIONAL UNIVERSITY of FOOD TECHNOLOGIES [ Наукові праці Національного університету харчових технологій ]
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