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1

Investigation of Infrared Thermography of Cortical Bone Grinding in Neurosurgery

Babbar Atul, Jain Vivek, Gupta Dheeraj, Goyal Kapil Kumar, Prakash Chander, Saxena Kuldeep Kumar, Kumar Sandeep, Bartoszuk Marian

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 1

116--123

EN

In this work, an effort has been made to determine the effect of different shape surgical burr on the thermogenesis during bone osteotomy. The abrasion during bone grinding leads to heat generation and subsequently rise in the temperature which may have adverse effects such as osteonecrosis, blood coagulation in the carotid artery, damage to sciatic nerves, and even loss of vision. So, mitigating the temperature rise during bone grinding is of paramount importance. Especially, in endoscopic endonasal approach (EEA) in which nasal passage is used for the inserting the grinding burr and reaching the target region. The miniature abrasion can significantly increase the temperature and hence leads to the thermal damage to nerves surrounding the temporal and frontal lobe. These parts of the brain controls movement, problem solving ability, behavior, personality mood, hearing, language, memory, speech, breathing, heart rate, consciousness etc. Furthermore, neurosurgeons rely on their personal surgical experience for estimating the temperature rise during grinding. However, this is much difficult for novice surgeons. Therefore, it becomes critically important to preserve the soft neural tissues and nerves amid bone grinding. To overcome these concerns, infrared thermography technique has been exploited to determine the possibility of thermogenesis during bone grinding by measuring the temperature rise and its distribution using infrared camera. All experiments have been carried at a constant set of process variables. The grinding zone is continuously flooded with the irrigating solution to remove the heat and bone debris away from the grinding site. It has been observed that convex tool shape generated lower maximum temperature i.e. 46.03 ℃ among all tools. The temperature produced by the convex tool is 12.06% lower than spherical tool, 33.39% lower than cylindrical tool, and 10.55% lower than tree-shape tool. The results showed that convex shape tool could prevent thermal necrosis in the bone as temperature caused (i.e. 46 ℃) was less than the threshold limit of osteonecrosis. Thermograms revealed that infrared thermography technique could be implemented for the in-vivo surgical operations for the measurement of temperature during bone grinding.

2

Preliminary Experimental Investigation of Cut-Resistant Materials: A Biomimetic Perspective

Kropidłowska Paulina, Irzmańska Emilia, Sawicki Jacek

Autex Research Journal

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2022

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Vol. 22, no. 4

411--418

EN

The objective of the work was the preliminary experimental investigation of cut-resistant materials including a biomimetic perspective. The effects of the cutting were expressed as static and dynamic cut resistance of the following materials: knitted fabrics, woven fabrics, continuously coated knitted fabrics, and dot-coated knitted fabrics. The cutting process gives rise to frictional forces, but the current test methods for cut-resistant gloves are not designed to measure them. Therefore additionally, the cut resistance of the material was evaluated using a modified procedure based on the standard EN 1082-1, taking into consideration grip strength tests to assess if there is a potential correlation between cut resistance and anti-slip properties.

3

Commercial sponges in heterogeneous catalysis: developing novel composites with cobalt and silver

Żółtowska Sonia, Modelska Martyna, Piasecki Adam, Jesionowski Teofil

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 6

89--100

EN

The use of commercial sponges in materials science has gained much recent attention. Their unique properties, namely a fibrous, rigid skeleton, thermal stability and resistance to acid and basic hydrolysis, have been the primary motivation to use them in the development of new composites. In this work, a simple method of immobilization of cobalt and silver cations, followed by their reduction using sodium borohydride, was successfully applied for the first time to obtain functionalized spongin scaffolds. Three different materials, labeled Co_spongin, Ag_spongin and Co-Ag_spongin, were prepared. Their morphological and physicochemical properties were explored using various techniques (SEM+EDS, TG/DTA, FTIR). The focal point of the research was the application of the resulting materials in the reaction of 4-nitrophenol reduction with sodium borohydride in water. It was found that all of the composites possess superior activity in the reduction of 4-nitrophenol, achieving high rate constants of 0.31 min-1 for Ag_spongin, 0.52 min-1 for Co_spongin and 0.86 min-1 for Co-Ag_spongin. Reusability tests showed that all of the composites could be reused five times. Additional structural analysis after catalytic application showed no visible changes in the morphology of the catalysts. The results indicate that spongin can be considered as a facile, cost-effective, renewable and environmentally friendly three-dimensional support for use in heterogeneous catalysis.

4

Synthetic extracellular matrix as a substrate for regenerative medicine

Stodolak-Zych Ewa, Menaszek Elżbieta, Twardy Aleksandra, Ścisłowska-Czarnecka Anna, Boguń Maciej, Kolesińska Beata

Engineering of Biomaterials

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2019

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Vol. 22, no. 152

10--15

EN

The work presents materials characteristics of fibrous polysaccharide substrates (calcium alginate, CA) modified with short peptides. Three types of synthesized peptides (hexapeptides) were composed of: cysteine (C) and tryptophan (W) named - (WWC)2or cysteine (C) and tyrosine (Y) named (YYC)2 or phenyloalanine (F) named 6F. The peptides size distribution (DLS method) showed that they agglomerated in an alcohol medium. These results were used to select a modification method of the fibrous substrates i.e. the peptides were deposited on the fibrous alginate substrate by the electrospraying technique. Using this method three kinds of polysaccharide- peptides systems were obtained i.e.: CA/(WWC)2, CA/(YYC)2CA/6F. As a reference material, the pure calcium alginate fibrous substrate was used. The results of modification with short peptides were evaluated via scanning electron microscopy (SEM): small aggregates were observed (40-100 nm) on the surface of fibers, and the fibers size remained the same after modification (11-12 μm). The size of aggregates depended on the kind of short peptide; the smaller (40 nm) aggregates were observed when the peptide had only aromatic chain (6F), the bigger (<100 nm) ones were observed when the peptide had heterocyclic rings in the chain (WWC and YYC). All materials were contacted with osteoblast-like cells (MG-63) to test biocompatibility (cells viability after 3 and 7 days) and the results proved showed higher viability in the polysaccharide-peptide system which increased with the time of observation. The durability of polysaccharide-peptide systems was tested using the enzymatic assay: collagenase confirmed the stability of materials. The progress of degradation rate was observed using infrared spectroscopy (FTIR-ATR) - the ratio on bands with C-O and C-OH increased after degradation under in vitro conditions.Results of the investigations on the fibrous substrates have confirmed that the system is a good model of an extracellular matrix (ECM) due to its chemical composition and microstructure which both have biomimetic characteristics. Thus, it may be used as a filling of bone defects supporting the regeneration of the damaged tissue. Additionally, it may also serve as the model research system of ECM.

5

Biomimetic Ca-P coatings obtained by chemical/electrochemical methods from Hanks' solution on a Ti surface

Pisarek M., Roguska A., Marcon L., Andrzejczuk M.

Engineering of Biomaterials

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2012

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Vol. 15, no. 113

29--32

EN

The purpose of this study was to investigate the bioactivity of porous calcium phosphate coatings on titanium prepared using a two-step procedure (chemical etching or anodic oxidation of Ti followed by soaking in simulated body fluid or direct electrodeposition from Hanks' solution). In order to evaluate the potential use of the coatings for biomedical applications, the adsorption of serum albumin, the most abundant protein in the blood, and the attachment of living cells (osteoblasts, U2OS) were studied.

6

Three-dimensional cfd analysis to study the thrust and efficiency of a biologicallyinspired marine propulsor

Lamas M. I., Rodríguez J. D., Rodríguez C. G., González P. B.

Polish Maritime Research

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2011

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nr 1

10-16

EN

Aquatic animals, which are the result of many millions of years of evolutionary optimization, are very quick, efficient, robust, and versatile. Accordingly, biologically-inspired mechanisms which emulate the movement of animals have recently become very popular. For the efficient design of a propulsion system it is very important to analyze the fluid flow in detail. CFD (Computational Fluid Dynamics) has become a powerful technique to understand the phenomena because it gives extensive information about the fluid flow characteristics. In the present work, a propulsion system consisting of an undulating fin which emulates the fish swimming was built. In order to optimize the mechanism, several undulating configurations were studied using a 3D turbulent CFD model. The thrust, drag, efficiency and hydrodynamic characteristics were analyzed. Furthermore, it was shown that the efficiency and thrust depend strongly on the oscillation frequency, amplitude and wavelength. In order to validate this CFD model, the numerically obtained thrust was successfully compared with experimental results from the laboratory mechanism.

7

Biomateriały kompozytowe

Chłopek J.

Kompozyty

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2009

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R. 9, nr 1

3-18

PL

Przedstawiony artykuł ma charakter przeglądowy i prezentuje możliwości wykorzystania materiałów kompozytowych w medycynie. Stosując podejście biomimetyczne związane z naśladowaniem budowy i właściwości naturalnych tkanek, pokazuje zasady projektowania syntetycznych kompozytów spełniających kryteria biozgodności i biofunkcyjności. Analiza dotyczy zarówno kompozytów włóknistych, jak i ziarnistych i prezentuje, jak stosując materiały kompozytowe zawierające aktywne fazy biologiczne, można uzyskać efekty synergiczne prowadzące dodatkowo do wspomagania procesu regeneracji uszkodzonych tkanek. Takie podejście jest możliwe przy ścisłej współpracy głównie dwóch dyscyplin naukowych - nauki o materiałach i biologii. Większość przedstawionych zagadnień opiera się na badaniach własnych autora z uwzględnieniem najnowszych tendencji w rozwoju biomateriałów. W szczególności dotyczy to bioaktywnych kompozytów, kompozytów z udziałem włókien węglowych i organicznych, głównie dla spełnienia funkcji biomechanicznej, nanokompozytów, kompozytów gradientowych oraz zjawisk na styku materiał kompozytowy-środowisko biologiczne (płyny fizjologiczne, komórki, tkanki). Przeprowadzona analiza właściwości mechanicznych i biologicznych kompozytów stwarza dobrą podstawę do projektowania i otrzymywania wielofunkcyjnych materiałów implantacyjnych.

EN

The presented article has a review character and it shows the possibilities of using the composite materials in medicine. Applying the biomimetic approach connected with mimicking the structure and properties of natural tissues, it presents the principles of designing synthetic composites fulfilling the biocompatibility and biofunctionality criteria. The analysis concerns both fibrous and particle composites and it shows how it is possible to achieve the synergetic effect leading additionally to supporting the regeneration process of damaged tissues using the composite materials with biologically active phases. Such an approach is possible thanks to the cooperation of mainly two disciplines: materials science and biology. The majority of presented problems is based on author's researches, taking into consideration the latest trends in biomaterials development. Particularly, it concerns bioactive composites, composites with carbon and organic fibers, mainly for fulfilling biomechanical function, nanocomposites, graded composites and phenomena on the border of composite material-biological environment (physiological fluids, cells, tissues). In the case of bioactive composites it has been shown how it is possible to obtain biologically active composite with enhanced mechanical properties and osteointegration ability by modification of the carbon-carbon composites manufacture process by hydroxyapatite particles addition. This effect was caused by the presence of two mechanisms: one connected with hydroxyapatite, the second one with TCP formed after hydroxyapatite decomposition. The investigations conducted on composites made of resorbable polymers, mainly by means of FTIR method, showed that the presence of modifying phases changes the resorption rate of polymer and influences bone tissue regeneration process. The modifiers (particles or fibers) can act as active scaffolds which stimulate the growth of bone tissue. The properties and the geometry of these phases can decide about cellular and tissue reactions. The presence of strongly developed interfaces in composite materials influences durability of the received implants. Creep tests at various stress levels carried out on polisulfone-carbon fiber composite revealed that life-time of such implants is shorter than for pure polymers. Graded materials with Young's modulus, porosity and resorption rate gradients can decide about the stress distribution, ability to overgrowth with bone tissue and blood vessels creation (vascularization). The analysis of properties of composite materials is a good base for designing and manufacturing multifunctional implants with controlled mechanical and biological behaviour.

8

Przeciwminowe roboty : pojazdy kroczące

Jankiewicz M.

Biuletyn Wojskowej Akademii Technicznej

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2007

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Vol. 56, nr 1

273-286

PL

W artykule przedstawiono nową klasę autonomicznych maszyn - robotów przeciwminowych, przeznaczonych do prowadzenia działań na lądzie, w strefie litoralnej oraz na wodach bardzo płytkich i płytkich (ang. VSW - Very Shallow Water, SW - Shallow Water). Zaprezentowano opracowane w USA konstrukcje biomimetycznych robotów kroczących, wzorowanych na budowie oraz cechach zachowań żywych organizmów, w ramach programów BURP (Biomimetic Underwater Robot Program) oraz BIODYNOTICS (The Biologically Inspired Multifunctional Dynamic Robotics). Omówiono przeznaczenie, budowę oraz sposoby zwalczania zagrożenia minowego prowadzone przez autonomiczne, kroczące pojazdy podwodne (ALUV’s - Autonomous Legged Underwater Vehicles).

EN

The article presents autonomous vehicles used for detection and clearance of land and naval mines on littoral zone and very shallow water. The data about US, BURP, and BIODYNOTICS programs including state of the art of innovative, biologically inspired legged robots are given. Also mine countermeasures based on ALUV’s (Autonomous Legged Underwater Vehicles) are presented.

9

Badania nad biomimetyczną metodą otrzymywania kanalikowych tworzyw ceramicznych o strukturze kości.

Zboromirska-Wnukiewicz B., Gryzło B., Rudziewicz T.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

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2006

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Vol. 44, nr 18

221-225

PL

Zasadniczym celem tej pracy jest opracowanie metod otrzymywania tworzyw ceramicznych charakteryzujących się specyficzną strukturą porów kanalikowych oraz badanie właściwości tych materiałów w aspekcie możliwości zastosowania ich' w implaniologii medycznej. Jako prekursorów użyto różnego rodzaju drewna. Prckursory otrzymywano na drodze pirolizy w atmosferze azotu. Konwersję struktur biologicznych w syntetyczne materiały ceramiczne prowadzono z zastosowaniem infiltracji związków krzemowych metodą zoi-żel. Następnie tak przygotowany materia! wypalano w atmosferze argonu. Otrzymany materiał poddano badaniom rentgenograficznym i mikroskopowym.

EN

Our aim in this work was working out a method for obtaining of ceramic materials with specific canal structure and research features of such materials in order to determination their usability in medical implantology. To obtain matrix for ceramic implants we have used different organic precursors like coniferous and deciduous woods. Matrix was obtained with method of pyrolysis in nitric atmosphere. Conversion of biological structures to ceramic material was obtained by infiltration of silicone compounds with method sol - gel. Than such prepared material was burned in argon atmosphere. Obtained material was examined by X-ray radiology and microscopic methods.