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Search results for: ULTRASOUND ASSISTED EXTRACTION
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Thermal Imaging in Wound Healing Diagnostics
PublicationResults of a project searching for objective, quantitative evaluation of postoperative wound healing in cardiosurgery are presented. We propose simple thermal models of the healing processes after cardiosurgery interventions as objective descriptors allowing classification of patients for extraction and following recovery at home or for prolonged treatment in a hospital. Classification of healing as the normal process or as a process...
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Oxidation step in the preparation of benzocamalexin: The crystallographic evidence
PublicationThe study of oxidation step in the preparation of benzocamalexin by the α-amidoalkylation–oxidation sequence revealed the formation of perchloro-1,2-phenylene dibenzoate as the product of transformation of tetrachloro- 1,2-benzoquinone applied as the oxidant. The structures of benzocamalexin and perchloro-1,2-phenylene dibenzoate were confirmed by X-ray diffraction analysis. The extraction step in the final isolation of benzocamalexin...
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Comparison of Methods for Real and Imaginary Motion Classification from EEG Signals
PublicationA method for feature extraction and results of classification of EEG signals obtained from performed and imagined motion are presented. A set of 615 features was obtained to serve for the recognition of type and laterality of motion using 8 different classifications approaches. A comparison of achieved classifiers accuracy is presented in the paper, and then conclusions and discussion are provided. Among applied algorithms the...
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Al-DIAMOND SCHOTTKY TUNNEL DIODES WITH BARRIER HEIGHT CONTROL
PublicationFew-nanometer-thick very highly boron-doped p-type layers were fabricated at metal-semiconductor interfaces of Schottky barrier diodes formed with aluminum on polycrystalline diamond. Preliminary results show that hermionically-assisted tunneling mechanism results in lower voltage drops at forward biasing of these diodes than expected for the Al-diamond metal-semiconductor potential barrier B. The effective barrier height Bpeff...
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Optimization of Single-Sided Lapping Kinematics Based on Statistical Analysis of Abrasive Particles Trajectories
PublicationThe chapter presents the influence of selected kinematic parameters on the geometrical results of the single-sided lapping process. The optimization of these parameters is aimed at improving the quality and flatness of the machined surfaces. The uniformity of tool wear was assumed as main optimization criterion. Lapping plate wear model was created and in detail was analyzed. A Matlab program was designed to simulate the abrasive...
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Quenching of bright and dark excitons via deep states in the presence of SRH recombination in 2D monolayer materials
PublicationTwo-dimensional (2D) monolayer materials are interesting systems due to an existence of optically non-active dark excitonic states. In this work, we formulate a theoretical model of an excitonic Auger process which can occur together with the trap-assisted recombination in such 2D structures. The interactions of intravalley excitons (bright and spin-dark ones) and intervalley excitons (momentum-dark ones) with deep states located...
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Monitoring of crosslinking of a DGEBA-PAMAM adhesive in composite/aluminium bonded joint using mechanical and ultra-sound techniques
PublicationAdhesive cure is an important and determining aspect of strength and stability of bonded structures. Crosslinking of the polymer leads to the adhesive strength, stiffness and durability. Depending on the resin and curing agent used, cure time can vary from minutes to weeks, even then 100% crosslinking not being guaranteed. Standard methods based on dynamic mechanical analysis (DMA) or calorimetric techniques (DSC, DTA) are valuable...
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Underwater Acoustic Imaging of the Sea
PublicationAcoustic waves are a carrier of information mainly in environments where the use of other types of waves, for example electromagnetic waves, is limited. The term acoustical imaging is widely used in the ultrasonic engineering to imaging areas in which the acoustic waves propagate. In particular, ultrasound is widely used in the visualization of human organs - ultrasonography (Nowicki, 2010). Expanding the concept, acoustical imaging...
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Diagnostics of the Peripheral Artery Disease with use of Glucose Sensor - A Proof of Concept
PublicationIt is estimated that 13 % of population over 50 years old suffer from symptomatic or asymptomatic peripheral artery disease (PAD). Ankle-brachial index (ABI) is viewed as a useful parameter in diagnostics of peripheral arterial disease, however screening tests with usage of this method are not advised. Hypoxia causes increase in lactate values and...
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Failure Monitoring and Condition Assessment of Steel-Concrete Adhesive Connection Using Ultrasonic Waves
PublicationAdhesive bonding is increasingly being incorporated into civil engineering applications. Recently, the use of structural adhesives in steel-concrete composite systems is of particular interest. The aim of the study is an experimental investigation of the damage assessment of the connection between steel and concrete during mechanical degradation. Nine specimens consisted of a concrete cube and two adhesively bonded steel plates...
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Niebezpieczeństwo ukryte w żywności-aminy biogenne. Cz. II. Metody oznaczania i wyzwania.
PublicationZe względu na aktywność biologiczną amin biogennych ich oznaczanie zarówno jakościowe, jak i ilościowe w żywności ma istotne znaczenie w celu zapewnienia ochrony zdrowia i życia ludzkiego. Obecnie do monitoringu amin biogennych w żywności najczęściej wykorzystuje się: wysokosprawną chromatografię cieczową (HPLC), chromatografię cienkowarstwową (TLC) oraz absorpcyjną spektrofotometrię cząsteczkową. Są to jednak techniki czasochłonne,...
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Data from the survey on motivation to study abroad and criteria for choosing a place to study for foreign graduates of Gdańsk University of Technology
Open Research DataThe dataset includes data from the survey on the Gdańsk University of Technology foreign graduates’ on motivation to study abroad and criteria for choosing a place to study. The research was conducted over a four-month period, from December 2019 to March 2020, using the Computer-Assisted Web Interview (CAWI). The research sample included 142 respondents....
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Determination of volatile organic compounds in water samples using membrane-solid phase microextraction (M-SPME) (headspace version)
PublicationThe results of a study on the use of membrane-solid phase microextraction (M-SPME) for sampling volatile organic compounds (VOCs) from the headspace above the liquid medium are presented. The sampled VOCs were subsequently quantified by gas chromatography (GC). Two systems were compared in this study, i.e. a novel two-phase sorption system (M-SPME), and a commercial fibre. Headspace sampling using SPME was optimized with respect...
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Preconcentration and Analytical Methods for Determination of Methyl Tert-Butyl Ether and Other Fuel Oxygenates and Their Degradation Products in Environment: A Review
PublicationFuel oxygenates (FOs) are mainly ethers or alcohols which are added to gasoline either to boost the octane number or to make the fuel burning process more "cleaner" with increasing the oxygen content, or to obtain a combination of both effects. FOs are water soluble with high mobility in the environment which presence even at very low concentrations lower the quality of water making it unsafe or unpleasant due to their objectionable...
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Optoelectronic system for investigation of cvd diamond/DLC layers growth
PublicationDevelopment of the optoelectronic system for non-invasive monitoring of diamond/DLC (Diamond-Like-Carbon) thin films growth during μPA ECR CVD (Microwave Plasma Assisted Electron Cyclotron Resonance Chemical Vapour Deposition) process is described. The system uses multi-point Optical Emission Spectroscopy (OES) and long-working-distance Raman spectroscopy. Dissociation of H2 molecules, excitation and ionization of hydrogen atoms...
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Ammonium <i>O</i>,<i>O</i>'-diethyl dithiophosphate
PublicationIn the title compound, NH4+·(C2H5O)2PS2−, the ammonium cation is connected by four charge-assisted N−H···S hydrogen bonds to four tetrahedral O,O'-diethyl dithiophosphate anions, forming layers parallel to (100). The polar and non-polar constituents of the layers are stacked alternately along [100]. Interlacing of the external ethyl groups...
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D-loop sequences retrieved from Canis lupus familiaris mitochondrial genome
Open Research DataCanine mitochondrial genome is built of 16727 bp. Non-coding control region (mtCR), called also D-loop, begins with 15458 nucleotide and ends with 16727 nucleotide. The length of this fragment is 1270 bp (Kim et al., 1998). D-loop region is responsible for replication and transcription of mitochondrial DNA. Mutations that occur within it may cause irregularity...
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Morphology control through the synthesis of metal-organic frameworks
PublicationDesignable morphology and predictable properties are the most challenging goals in material engineering. Features such as shape, size, porosity, agglomeration ratio significantly affect the final properties of metal- organic frameworks (MOFs) and can be regulated throughout synthesis parameters but require a deep under- standing of the mechanisms of MOFs formation. Herein, we systematically summarize the effects of the indi- vidual...
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Semantic URL Analytics to Support Efficient Annotation of Large Scale Web Archives
PublicationLong-term Web archives comprise Web documents gathered over longer time periods and can easily reach hundreds of terabytes in size. Semantic annotations such as named entities can facilitate intelligent access to the Web archive data. However, the annotation of the entire archive content on this scale is often infeasible. The most efficient way to access the documents within Web archives is provided through their URLs, which are...
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Solid phase microextraction: state of the art, opportunities and applications
PublicationSolid phase microextraction is one of the most popular green techniques used for sample preparations in analytical chemistry. It is a simple, rapid, sensitive, and solvent-free technique. Since SPME was first introduced in the early 1990s, there has been an intensification of research in order to elaborate new methodical solutions in many research facilities around the world, which could increase the use of this technique. More...
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Investigation of tetrabutylammonium bromide-glycerol-based deep eutectic solvents and their mixtures with water by spectroscopic techniques
PublicationDeep eutectic solvents (DES) are formed by an acceptor and a donor of hydrogen bonds. They are generally considered as a possible alternative to hazardous organic solvents in various fields. Very recently they have also appeared in analytical chemistry, used mainly for the separation of analytes before instrumental quantification. For the development of new extraction procedures, it is important, among other things, to understand...
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Determination of flavanols by liquid chromatography with fluorescence detection. Application to the characterization of cranberry-based pharmaceuticals through profiling and fingerprinting approaches
PublicationIn this work, a new method based on reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) was established for the determination of catechins and related oligomeric proanthocyanidins (PACs) in cranberry-based pharmaceuticals. Compounds were recovered by liquid extraction using methanol/water/hydrochloric acid (60:39:1, v:v:v) as the extraction solvent. The chromatographic separation was carried...
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Influence of Storage Time and Temperature on the Toxicity, Endocrine Potential, and Migration of Epoxy Resin Precursors in Extracts of Food Packaging Materials
PublicationThe aim of the present study was to establish a standard methodology for the extraction of epoxy resin precursors from several types of food packages (cans, multi-layered composite material, and cups) with selected simulation media (distilled water, 5% ethanol, 3% dimethyl sulfoxide, 5% acetic acid, artificial saliva) at different extraction times and temperatures (factors). Biological analyses were conducted to determine the acute...
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Entanglement-redistribution boxes
PublicationWe establish a framework to study the classical-communication properties of primitive local operations assisted by classical communication which realize various redistributions of entanglement, like, e.g., entanglement swapping. On the one hand, we analyze what local operations and how much classical communication are needed to perform them. On the other hand, we investigate whether and to what extent such primitives can help to...
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SAFE - technika izolacji związków zapachowych z próbek żywności
PublicationOznaczanie składników odpowiedzialnych za zapach produktów żywnościowych dokonywane za pomocą technik chromatograficznych obejmuje dwa zasadnicze etapy: przygotowanie próbki i identyfikację (rozdzielenie połączone z odpowiednią metodą detekcji). Ze względu na skomplikowaną matrycę, specyfikę związków zapachowych - samoistne ich uwalnianie z matrycy, jak i możliwość zachodzenia przemian, kluczowym elementem analizy żywności jest...
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Salicylaldimine-based receptor as a material for iron(III) selective optical sensing
Publicationα,α-Bis(salicylimino)-m-xylene (L) was prepared using both conventional and microwave-assisted procedure. The compound exhibits ability to colorimetric recognition of iron(III) ions in aqueous environment, what is shown by significant color change from yellow to purple. In DMSO : water (9:1 v/v) solvent system receptor creates with iron(III) cations complexes of 2:1 stoichiometry (L:Fe3+) with stability constant (log K) 7.54±0.21....
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Miniaturized dual‐band branch‐line coupler with enhanced bandwidth
PublicationIn this letter, a miniaturized hybrid dual-band branch-line coupler (BLC) with enhanced fractional bandwidths is proposed. Compact size and bandwidth enhancement are obtained using meandered transmission line sections with broken symmetry between cross-coupling branches. The circuit is designed at a low numerical cost using surrogate-assisted techniques. The optimized design features small size of only 0.25λg×0.19λg(28% miniaturization...
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Nested Kriging Surrogates for Rapid Multi-Objective Optimization of Compact Microwave Components
PublicationA procedure for rapid EM-based multi-objective optimization of compact microwave components is presented. Our methodology employs a recently developed nested kriging modelling to identify the search space region containing the Pareto-optimal designs, and to construct a fast surrogate model. The latter permits determination of the initial Pareto set, further refined using a separate surrogate-assisted process. As an illustration,...
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ZnO-decorated green-synthesized multi-doped carbon dots from Chlorella pyrenoidosa for sustainable photocatalytic carbamazepine degradation
PublicationThe promising green synthesis of carbon dots (CDs) from microalga Chlorella pyrenoidosa was achieved using simple hydrothermal and microwave-assisted methods. Doping of nanomaterials by nonmetals (N, S, and P) was confirmed by X-ray photoelectron spectroscopy (XPS), while the existence of metals in the CDs was confirmed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and transmission electron microscopy (TEM),...
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The impact of filler thermomechanical modifications on static and dynamic mechanical performance of flexible foamed polyurethane/ground tire rubber/zinc borate composites
PublicationThe rapid development of the automotive industry is very beneficial to many aspects of human life, but it is also a very significant environmental burden. The most straightforward impact is related to the generation of exhaust, but the management of post-consumer car parts is also a major challenge. Among them, waste tires are very burdensome due to their enormous numbers. Therefore, it is essential to develop novel, environmentally...
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Low-cost multi-criterial design optimization of compact microwave passives using constrained surrogates and dimensionality reduction
PublicationDesign of contemporary microwave circuits is a challenging task. Typically, it has to take into account several performance requirements and constraints. The design objectives are often conflicting and their simultaneous improvement may not be possible; instead, compromise solutions are to be sought. Representative examples are miniaturized microwave passives where reduction of the circuit size has a detrimental effect on its electrical...
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BREAST, Lower-inner quadrant of breast - Female, 48 - Tissue image [2270630026309831]
Open Research DataThis is the histopathological image of BREAST tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Intraductal papilloma - Female, 45 - Tissue image [6260730021883181]
Open Research DataThis is the histopathological image of BREAST tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Data from the survey on assessment of satisfaction with graduating from Gdańsk University of Technology in the opinion of foreign graduates
Open Research DataThe dataset includes data from the survey on the Gdańsk University of Technology foreign graduates’ on assessment of satisfaction with graduating from university. The research was conducted over a four-month period, from December 2019 to March 2020, using the Computer-Assisted Web Interview (CAWI). The research sample included 142 respondents. The study...
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Identification of regions of interest in video for a traffic monitoring system
PublicationA system for automatic event detection in the camera image is presented in this paper. A method of limiting a region of interest to relevant parts of the image using a set of processing procedures is proposed. Image processing includes object detection with shadow removal performed in the modified YCbCr color space instead of RGB. The proposed procedures help to reduce the complexity of image processing algorithm and result in...
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Knowledge representation of motor activity of patients with Parkinson’s disease
PublicationAn approach to the knowledge representation extraction from biomedical signals analysis concerning motor activity of Parkinson disease patients is proposed in this paper. This is done utilizing accelerometers attached to their body as well as exploiting video image of their hand movements. Experiments are carried out employing artificial neural networks and support vector machine to the recognition of characteristic motor activity...
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Determination of chlorine concentration using single temperature modulated semiconductor gas sensor
PublicationA periodic temperature modulation using sinusoidal heater voltage was applied to a commercial SnO2 semiconductor gas sensor. Resulting resistance response of the sensor was analyzed using a feature extraction method based on Fast Fourier Transformation (FFT). The amplitudes of the higher harmonics of the FFT from the dynamic nonlinear responses of measured gas were further utilized as an input for Artificial Neural...
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Generalized adaptive comb filter with improved accuracy and robustness properties
PublicationGeneralized adaptive comb lters can be used to identify/track parameters of quasi-periodically varying systems.In a special, signal case they reduce down to adaptive comblters, applied to elimination or extraction of nonstationarymulti-harmonic signals buried in noise. We proposea new algorithm which combines, in an adaptive way, resultsyielded by several, simultaneously working generalizedadaptive comb lters. Due to its highly...
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Selection of Features for Multimodal Vocalic Segments Classification
PublicationEnglish speech recognition experiments are presented employing both: audio signal and Facial Motion Capture (FMC) recordings. The principal aim of the study was to evaluate the influence of feature vector dimension reduction for the accuracy of vocalic segments classification employing neural networks. Several parameter reduction strategies were adopted, namely: Extremely Randomized Trees, Principal Component Analysis and Recursive...
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Poly(hydroxybutyrate-co-hydroxyvalerate) as a biodegradable binder in a negative electrode material for lithium-ion batteries
PublicationIn this work, graphite-based negative electrode for lithium-ion battery consisting a novel and biodegradable binder poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) is compared with standard graphite electrode with polyvinylidene fluoride (PVDF) as a binder. The rate and cycling performance of lithium ion insertion/extraction of electrodes with PHBV in a half-cell configuration are evaluated. Moreover, on the basis of the electrochemical...
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A rapid dispersive liquid–liquid microextraction of antimicrobial onion organosulfur compounds in animal feed coupled to gas chromatography-mass spectrometry
PublicationA rapid analytical procedure is proposed for determining two antimicrobial onion organosulfur compounds, propyl disulfide (PDS) and propyl propane thiosulfonate (PTSO), in animal feed. The use of PTSO as a natural ingredient in animal feed is allowed due to its antimicrobial activity against pathogenic organisms. Two analytical methodologies using gas chromatography coupled to mass spectrometry (GC-MS) are compared. After the extraction...
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Green adsorbents and solvents in food analysis
PublicationGreen analytical chemistry aims to minimize the negative impact of analytical procedures on the environment and human health. This can be achieved through the use of non-toxic and environmentally friendly reagents. Classical green solvents include water, ethanol, acetone, and supercritical fluids. Water has been used for the extraction of water-soluble compounds (sugars, amino acids). Ethanol and acetone have been used for the...
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Ekstrakcja do fazy stałej niejedno ma imię
PublicationW czasach, gdy we wszystkich przejawach aktywności człowieka trzeba się odnieść do przesłanek leżących u podstaw zrównoważonego rozwoju trudno jest uzasadnić stosowanie w praktyce analitycznej takich procedur i operacji, które pociągają za sobą konieczność:użycia dużych ilości rozpuszczalników i odczynników chemicznychdużych nakładów energii czy też przyczyniają się do wzrostu ekspozycji pracowników laboratoriów na niekorzystne...
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Paweł Możejko dr hab.
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Photocatalytic decolourization of Rhodamine-B dye by visible light active ZIF-8/BiFeO3 composite
PublicationIn this work, preparation of ZIF-8 supported BiFeO3 photocatalyst by ultrasound cavitation technique was reported. The synthesized materials were characterized using solid UV absorption spectroscopy, Raman Spectroscopy, and SEM. The catalytic function of synthesized photocatalyst under ultraviolet and visible light was examined for the decolourization of Rhodamine-B (Rh-B) dye. To understand the action of the photocatalyst on Rh-B...
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Metal–Organic Frameworks (MOFs) for Cancer Therapy
PublicationMOFs exhibit inherent extraordinary features for diverse applications ranging from catalysis, storage, and optics to chemosensory and biomedical science and technology. Several procedures including solvothermal, hydrothermal, mechanochemical, electrochemical, and ultrasound techniques have been used to synthesize MOFs with tailored features. A continued attempt has also been directed towards functionalizing MOFs via “post-synthetic...
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Benign neoplasm of breast - Female, 57 - Tissue image [617073002673701]
Open Research DataThis is the histopathological image of BREAST tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Other benign mammary dysplasias - Female, 48 - Tissue image [2270630026306941]
Open Research DataThis is the histopathological image of BREAST tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Other benign mammary dysplasias - Female, 48 - Tissue image [2270630026308791]
Open Research DataThis is the histopathological image of BREAST tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Fibroadenoma, NOS - Female, 35 - Tissue image [8020729577657811]
Open Research DataThis is the histopathological image of BREAST tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.