bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological Variations of Posterior Segmental Artery of the Single Renal Artery. Study on corrosion casts
Authors: Pop Elena , Sarau Cristian Andrei , Bardan Razvan , Lighezan Daniel Florin , Latcu Silviu , Sapte Elena , Pusztai Agneta Maria , Balint Germaine Savoiu , Bolintineanu Sorin Lucian
Published: January 2020

On a total of 150 renal corrosion casts were examined the posterior branch and the artery of renal posterior segment. For the origin of the posterior branch, there have been highlighted three morphological types, namely: Type I, bifurcation in anterior and posterior branches (92.67% of cases); Type II, trifurcation in anterior, posterior and superior or inferior branches (6.00% of cases); Type III, quadrifurcation in anterior, posterior, superior and inferior branches (1.33% of cases). Depending on the relations between this path and those with the posterior aspect of the renal pelvis, we highlighted four morphological types: Type I (62.67% of cases) with large extension of the posterior segmental artery, convex downward path and multiple subsegmentary branches; Type II (34.00% of cases) with large extension of the posterior segmental artery, that bifurcates or trifurcates in segmental branches and convex downward path; Type III (2.00% of cases) with small extension of the posterior segmental artery, with downward path in relation to the upper portion of the posterior surface of the renal pelvis upper portion; Type IV (1.33% of the cases) with small extension of the posterior segmental artery, with upward trajectory in relation to the lower portion of the renal pelvis. Knowledge of these aspects is important both to investigate morphological imaging and for performing partial resection of the renal parenchyma.
Research Regarding the Impact Behaviour of Some Polymeric Bio-composite Products for Orthopedic Use
Authors: Opran Constantin , Cotoros Diana , Roman Nadinne , Repanovici Angela , Miclaus Roxana
Published: January 2020

Polymeric bio-composites have special characteristics and use in various areas such as: automotive, aviation and aeronautic industries, civil engineering and for medical devices manufacturing. This paper presents the evaluation of impact behaviour of some types of materials suitable for orthopaedic use. As composites behave very differently at different rates of loading, static strength tests cannot be used to predict impact behaviour in the perspective of prosthetic medical devices study and manufacture. The used testing machine is Instron Dynatup Impact System with Data Acquisition and Control, model 8200, with assisted system of data acquisition and control.
Thermoplastic Materials Used for Fabrication of Maxillary Obturator Prostheses Experimental compression and traction tests
Authors: Urechescu Horatiu , Pricop Marius , Pricop Cristiana , Mateas Marius , Natanael Simon , Galatanu Sergiu Valentin
Published: January 2020

Maxillary obturator prostheses are dental devices used to close palatal defects created by surgical resection of different type of tumors, congenital malformation or trauma. The most popular material used for denture fabrication is the polymethyl methacrylate (PMMA). In recent years thermoplastic resins has attracted attention as a denture base material. This paper presents experimental compression and traction tests of VertexTMThermoSense from Vertex-Dental B.V. VertexTMThermoSense is a thermoplastic material based on a compounded mixture of Polyamide and pigments used in the fabrication of removable full and partial dental prostheses. Test results show that the average compressive yield strength of the samples is 60.18 MPa. The result of the tensile test showed an average of 49.4 MPa yield strength. VertexTMThermoSense has a very good average of the yield strain of 10%. The average of Young modulus is 1050 MPa.
The Benefits of the Plastination Techniques for the Anatomo Clinical Studies of Ankle Joint Ligaments Injuries
Authors: Sisu Alina Maria , Noditi Gheorghe , Grigorescu Dan , Floresc Sorin , Patrascu Jenel Marian , Patrascu Jr. Jenel Marian , Pop Elena , Bolintineanu Sorin Lucian
Published: January 2020

The present research was made by following three directions: dissection and plastination, clinical ankle joint ligament injuries and MRI and CT examination of the cases.191 cases of ankle joint ligament injuries have been studied during two years. They were examined clinically and radiologically, using CT and MRI testing. The classification of ankle sprain was based on the number of injured ligaments. Out of the 191 cases diagnosed with ligament injuries, 92 involved the anterior talofibular ligament, 54 in the calcaneofibular ligament, 40 involved the posterior talofibular ligament and 5 involved the deltoid ligament. First degree sprain involves the injury of the anterior talofibular ligament, the second degree sprain involves the injury of the anterior talofibular ligament and of the calcaneofibular ligament, and the third degree sprain involves the damaging of anterior and posterior talofibular ligaments, as well as the calcaneofibular ligament. In this paper we have diagnosed a number of 39 first degree springs, 12 of second degree springs and 41 of third degree springs. The standard X- ray examinations have a low diagnostic rate of the ankle ligament injuries. Conventional MRI has a higher accuracy in diagnosing ankle joint collateral ligaments lesions.
Structure and Magnetic Properties of Composite Toroids Powder Casted
Authors: Nabialek Marcin , Bloch Katarzyna , Szota Michal , Sandu Andrei Victor
Published: January 2020

The paper presents the results of research for magnetic composites made of metallic filler from alloy Fe65Co10Ni3W2B20 and epoxy resin EPIDIAN 100. The composites studied contained less than 10% of the resin, making them dimagnetoelectrics. The structure of alloys and composites was investigated using X-ray diffraction and scanning electron microscopy and their magnetic properties using a vibration magnetometer. It has been shown that the structure and properties of the composites depend on the chemical composition of the metallic filler. And good link between components, with the proper placement of the filler in the matrix, has an impact on the quality of the composite.
In Vitro Effects of Biomaterials on Mesenchymal Stem Cells Viability and Proliferation
Authors: Tanasie Gabriela , Bojin Florina , Tatu Romulus Fabian , Sisu Alina Maria , Cristea Mirabela , Puscasiu Daniela Anca , Nemes Emanuel Adelin , Tatu Carmen Sofica
Published: January 2020

Mesenchymal stem cells (MSCs) are increasingly being used in regenerative medicine to repair various tissue types. This study aimed to assess changes in MSCs properties as a result of their interaction with two biomaterials in order to evaluate their in vitro compatibility. We have used two types of biomaterials, as follows: hydroxyapatite anodized titanium (HA-Ti) is used in bone reconstruction; it is hard and remains in the body, while patches of collagen combined with poly-e-caprolactone (C-PCL) are utilized in the reconstruction of soft tissue (particularly the skin); these patches resorb in the body, being only a temporary matrix that fosters and accelerates tissue formation. We have chosen to assess changes in morphology, viability and proliferation of MSCs obtained by lipoaspirate, through direct contact with the biomaterial or in eluate. MSCs properties were assessed by optical microscopy, fluorescence microscopy after acridine orange/ethidium bromide (AO/EB) staining, and the MTT assay. After result interpretation, we gained an image of the cytotoxicity phenomenon seen during the experiment and were able to assess viability of cell in contact with the biomaterials used. HA-Ti shows better interaction with cells, which preserve their viability, and does not influence MSCs growth, proliferation or morphology. In contrast, cells on C-PCL matrix become small, spherical, were detached from the plate and had lower viability percentage.
Possible Dynamics of Polymer Chains by Means of a Ricatti s Procedure - an Exploitation for Drug Release at Large Time Intervals
Authors: Cobzeanu Bogdan Mihail , Irimiciuc Stefan , Vaideanu Dorin , Grigorovici Alexandru , Popa Ovidiu
Published: January 2020

In this paper, we propose an analyzis method for the dynamics of polymer chains, based on a Ricatti procedure induced by possible correlations through the compatibility of the thermal radiation-classical damped oscillator dynamics. Then, the quantification (radiation frecquency is directly proportional to the color temperature) and the erasure of one bit of information becomes a natural processes induced by the system structure itself. The theory has implications in the dynamics of biological structures (arhitecture of tumors, information on tumor growth and angiogenesis, etc.) in the form of Resonant Recognition Model.
Hematoxylin - Eosin-Methylene Blue Staining in a Dog Hepatic Amyloidosis Case
Authors: Stancu Adrian , Carpinisan Liliana , Ghise Alina , Pentea Marius , Berceanu Vaduva Delia Mira , Velimirovici Dana Emilia , Cristina Romeo
Published: January 2020

A post-mortem examination of an 1,5 years old Shar- Peis, dog was performed in order to find out the death cause. The macroscopically examination revealed a large amount of blood in the abdominal (hemoperitoneum) The liver was sampled for histopathological examination. Hematoxylin-eosin-methylene blue staining wasperformed in order to prepare the samples for microscopical examination. Based on the specific histopathological changes and taking into account all the pathological data, the diagnosis was liver amiloidosis.
Development of a Modified - release Drug Delivery System with Bexarotene Loaded in Clinoptilolite
Authors: Ochiuz Lacramioara , Ghiciuc Cristina , Ignat Maria , Popa Marcel , Peptu Catalina Anisoara , Vasile Aurelia
Published: January 2020

Developing biomaterials with optimal loading properties and controlled release of drugs is a priority of medical research. Clinoptilolite is a natural zeolite used in various industrial processes. Its texture and structure recommend its use as a biocompatible matrix for the development of modified release drug delivery systems. The present study aims to develop and characterize modified-release systems based on bexarotene loaded clinoptilolite. Bexarotene is a retinoid that is used as an anticancer agent in the topical treatment of cutaneous T-cell lymphoma. By adding bexarotene to these systems, skin delivered antineoplastic therapy with bexarotene can be improved. Clinoptilolite was obtained by purifying the volcanic tuffs from Mirsid quarry, Salaj Romania. After thermal and chemical purification, two monoionic forms of clinoptilolite were obtained. They were labeled as Na-CLI and H-CLI, respectively. Their texture and structure were characterized by specific methods. Subsequently, these forms of clinoptilolite were used as hosts for bexarotene loading by wet impregnation. The obtained results showed that the two modified-release systems Bxt@Na and Bxt@H, respectively, have no incompatibilities and provide prolonged release of the drug.
Statistical Analysis of Some Mechanical Characteristics of Glass Fiber Reinforced Composites
Authors: Spanu Paulina , Amza Catalin Gheorghe , Dinu Gabriela
Published: January 2020

This paper presents the results of the experimental researches obtained in the three-point test of the glass-fiber-reinforced polymeric composites. Mathematical modeling of experimental results was performed using a virtual instrument (VI) developed in the graphical programming language called LabVIEW. In order to process the experimental data and display the results, the virtual instrument (VI) allows both the reading of experimental data from a saved text file from the same folder as the current VI file and the direct entry of experimental values into a control element disposed on its front panel. The virtual instrument described in this article is part of a more complex project used for the mathematical modeling of the experimental data obtained in determining the physic-mechanical characteristics of glass fiber randomly reinforced polymeric composites.
In vitro Testing of Experimental and Commercial Bracket Bonding Materials
Authors: S. Mesaros Anca , Romanec Cristian , Mezaros Michaela , Moldovan Marioara , Baldea Ioana
Published: January 2020

The aims of our study were to assess the cytotoxic effect of five orthodontic bonding materials, in vitro, on HUVECs to study the induction of apoptosis and inflammatory response generated to assess the shear-bond strength of the 5 tested materials in order to quantify their performance. Standardized samples from each material were obtained and incubated with HUVEC cells for 24 and 72 h immersed in complete medium. Cell viability was determined by means of MTS method. Active caspase 3 and TNFa protein levels were measured through ELISA techniques. The shear-bond strength was tested on 60 extracted premolars which were bonded with the same type of bracket, using the 5 different materials. Statistical analysis Student T-tests, Chi-square and Anova tests were used for results interpretation. Cell viability was decreased with material exposure in a time dependent manner. All materials exerted cytotoxic effects, the experimental materials showed a significantly higher decrease in cell viability at the 72 h reading. Shear Bond strength was superior for the resin commercial bracket-bonding materials. The study shows that orthodontic adhesives� cytotoxicity and physical performance is related to their chemical properties and proves that all orthodontic practitioners should use freely their material of choice on condition they are aware of all its� properties.
Polypropylene Mesh in Minimally Invasive Treatment of Female Stress Urinary Incontinence
Authors: Grigore Nicolae , Pirvut Valentin , Mihai Ionela , Hasegan Adrian , Antonescu Elisabeta , Coldea Liliana , Mitariu Sebastian Ioan Cernusca
Published: January 2020

Stress urinary incontinence in women is a condition widely encountered in the entire world with a prevalence between 12.8% and 46.0%. Stress urinary incontinence is a public health problem causing a significant decrease in quality of life, involving social, physical, psychological, occupational and sexual suffering of patients. The minimal invasive treatment of the stress urinary incontinence (SUI) consists in fixing a suburethral polypropylene mesh (SPM) in retropubic (TVT) or transobturator (TOT) space, in order to regain the pelvic support of the urethra, with the consecutive augmentation of the pressure of urethral closing during effort. The objective of this paper is to present the advantage of SPM in the SUI treatment in the eleven years� experience of Department of Urology Sibiu.
Synthesis and Physico-Chemical Evaluation of Polyurethane Microstructures for Transmembrane Delivery of Reynoutria japonica Extract
Authors: Ardelean Florina , Susan Razvan , Borcan Florin , Moaca Alina , Antal Diana Simona , Soica Codruta , Moldovan Roxana , Vaduva Delia Berceanu , Marti Daniela
Published: January 2020

Polymer microstructures containing plant extracts are a novel technique used to increase the bioavailability of active agents with low aqueous solubility. Japanese knotweed (Reynoutria japonica) is an invasive plant with multiple biomedical properties. The aim of the present study was to obtain and characterize polyurethane microstructures used as a drug delivery system of a Japanese knotweed extract. The results indicate the obtaining of microstructures with an almost neutral pH, with sizes between 540 and 1134 nm, with a medium stability against the tendency to form clusters and a very good thermal stability. These first results present the potential of the obtained polyurethane microstructures as candidates for the transmembrane drug delivery of Japanese knotweed extracts, as a starting point for further bioactivity investigations.
Study Regarding the Surface State of Composite Resins After Finishing and Polishing Using Different Systems
Authors: Andrian Sorin , Iovan Gianina , Pancu Galina , Topoliceanu Claudiu , Georgescu Andrei , Stoleriu Simona , Taraboanta Ionut , Nica Irina
Published: January 2020

The aim of this study was to evaluate the influence of different finishing and polishing systems and of composite resins structure on surface state of the restoration. Cylindrical samples from two different composite resins (Filtek Z 550 and Filtek Z 250, 3M ESPE) were obtained. In group 1 the samples were not finished and polished. In groups 2-4 the samples were submitted to finishing procedure using two tungsten carbide burs, then polished using three different polishing systems: three steps diamond abrasive polishers (Kenda CGI, Lichtenstein) - group 2, one step silicon carbide abrasive particles brush (Occlubrush, KerrHawe SA, Switzerland) - group 3 and two steps Sof-Lex spiral wheels (3M ESPE) - group 4. Half of the samples in each group were subjected to surface microstructure evaluation using a scanning electron mycroscope. The other half of the samples was subjected to surface state assessment using profilometery. All the investigated finishing and polishing systems leaded to increased surface roughness when compared to the roughness of composite resins placed in direct contact to celluloid clear matrix. The surface roughness of both microfilled-hybrid and nanofilled-hybrid composite resins finished and polished with different systems were influenced mostly by the polishing system and less by the composite resin structure.
Treatment Planning Optimization in Radiotherapy Using the Bolus
Authors: Munteanu Anca , Ivan Florina Daniela , Patrascu Alexandru , Balan Vera , Ursache Catalina , Verestiuc Liliana
Published: January 2020

The present paper presents the results of the research regarding the bolus structure (Bio-Rad Win-IR instrument), the elasticity modulus, the bioadhesiveness properties (TA-XT2 Plus analyzer) and the clinical applications of the bolus in the adjuvant irradiation after radical mastectomy (Treatment Plan System Eclipse). The dose-volume histogram has made a comparative evaluation for with and without bolus treatment plans and confirmed the importance of bolus utilisation in selected patients. Conclusions: the thickness of the applied bolus is dependent on the skin dose required, on the treatment technique and must be equal to the depth of the build-up region for the removal of the skin-sparing effect of a high energy radiation.
Morphology and Rheology of Nanofilled PP / PVA Blends
Authors: Rezanova Natalia , Budash Yurii , Plavan Viktoriia , Ishchenko Olena , Bulakh Viktoriia
Published: January 2020

The influence of Ag/SiO2 as nanofiller and sodium oleate as compatibilizer and their mixtures on the patterns flow and structure formation processes in thermodynamically incompatible polypropylene/plasticized polyvinylalcohol (PP / PVA) systems were studied. It is found that the change in the sequence of mixing the ingredients of the composition allows adjusting the morphology phase type due to the predominant localization of nanoparticle additives in the melt amount of a component or on the border of phase separation. Injection of Ag/SiO2 to melt PP increases dispersion degree and homogeneity of its distribution in the matrix. Simultaneous use of nanoadditive and sodium oleate as compatibilizer improves the connections between the polymers and promotes thinner and more homogeneous dispersion of the particles of the dispersed phase. It is shown that the effective viscosity of melt nanofilled system is determined by components mixing method: viscosity of melt blend increases when the additive is localized predominantly in the PVA and decreases with the prior injection of PP. The nature of the flow for all researched compositions obeys a power law and almost does not depend on the method of mixing. The ability of the longitudinal deformation of ternary blends is deteriorating, but remains sufficient for their processing. Combining nanoadditive with compatibilizer promotes increased elasticity and the melt spinnability of modified blends.
Custom Designed Orthodontic Attachment Manufactured Using a Biocompatible 3D Printing Material
Authors: Nagib Riham , Szuhanek Camelia , Moldoveanu Bogdan , Negrutiu Meda Lavinia , Sinescu Cosmin , Brad Silviu
Published: January 2020

Treatment of impacted teeth often implies placing a bonded attachment and using orthodontic forces to move the tooth into occlusion. The aim of the paper is to describe a novel methodology of manufacturing orthodontic attachments for impacted teeth using the latest CAD software and 3D printing technology. A biocompatible acrylic based resin was used to print a custom made attachment designed based on the volumetric data aquired through cone bean computer tomography. Custom design of the attachment simplified clinical insertion and treatment planning and 3D printing made its manufacturing easier. Being a first trial, more reasearch is needed to improve the methodology and materials used.
Monitoring of Mercury Content in the Main Environmental Components Caused by Lignite Combustion in Large Thermal Power Plants
Authors: Badea Delia Nica , Dumitru Mihaela Gabriela , Cretescu Igor
Published: January 2020

The aim of experiment was to evaluate the local impact of mercury accumulations, discharge from coal power plants, by examining samples of ash, slag, soil, spontaneous vegetation and crop plants, using as analytical techniques the cold vapor atomic absorption spectroscopy. Mercury determined in samples of lignite (0.020 mg. Kg-1), is found in fly ash samples retained by filters (0.037 mg.Kg-1), bottom ash transported hydraulic in deposit (0.022 mg.Kg-1), adjacent soils landfill and the power plant (0.12 mg.Kg-1 or 0.049 mg.Kg-1). The mercury content in vegetation presents differentiated values depending on the bioavailability of plant, area and the positioning of the emission source, reaching values between 0.014 at 0.005 mg.Kg-1 in the wild flora and 0.022 mg.Kg-1 to 0.004 mg.Kg-1 for plants crop. Data obtained for plants, confirmed that most families tend to accumulate mercury plant in larger quantities in the roots (0.022 � 0.0016 mg.Kg-1) and moderate quantities in the foliar level by translocation or by direct vapor absorption.
Chylothorax Consecutive Heartworm Disease in Dog
Authors: Stancu Adrian , Ghise Alina , Pentea Marius , Berceanu Vaduva Delia Mira , Velimirovici Dana Emilia , Carpinisan Liliana , T.cristina Romeo
Published: January 2020

Chylothorax was diagnosed in a Afghan dog 3 year old, that presented in the necropsy a accumulation of lymphatic fluid in the chest cavity. Also to examine the right heart was observed to this heartworms - Dirophylaria immitis.
ASSESSMENT OF PHYSICAL PROPERTIES OF STRUCTURED OILS AND PALM FAT
Authors: Gur Sylwia Onacik , Zbikowska Anna , Przybysz Marzena , Kowalska Malgorzata
Published: January 2020

Oleogels are structured liquid oils with applications in food, cosmetic, and pharmaceutical industries. Structured oils may become alternatives to the commonly used solid fats, such as palm fat or hydrogenated fats. Properties of oleogels are primarily dependent on the structuring agent applied. This paper was intended as an examination of structuring properties and oleogel oil binding capacities of various monomer ingredients (plant and beeswaxes, monoacylglycerol) and comparison of the oleogels produced with palm fat. An oleogel produced with candelilla wax (CLX) exhibited a structure most similar to that of palm fat. These products showed statistically significant differences of colour from palm fat. In addition, textures of the oleogels differed from one another and from palm fat. Oleogel containing rice bran wax (RBX) had the most similar viscosity properties. Oleogels including candelilla wax and yellow bees wax displayed best oil binding structures (assayed by centrifugal and LumiSizer methods). When filtered (at 40�C), on the other hand, minimum oil loss after 24h was demonstrated by the oleogels containing CLX and RBX, possible evidence that these structure-forming substances roduce oleogels that could be used in products exposed to more elevated temperatures. Oleogels may become alternatives to the commonly used solid fats. Thanks to the use of oil structuring agent at the level of 3% liquid oil becomes solid. Using these innovative fat products can stabilize oil in the product, and also it can improve the nutritional value of food products by replacing a popular palm fat rich in saturated fatty acids, which exert an adverse influence on humans� cardiovascular system, by oils rich in unsaturated fatty acids.
Fiber Reinforced Composite Materials for Proton Radiation Shielding
Authors: Condruz Mihaela Raluca , Puscasu Cristian , Voicu Lucia Raluca , Vintila Ionut Sebastian , Paraschiv Alexandru , Mirea Dragos Alexandru
Published: January 2020

Nowadays scientific researchers aim to develop new material designs for space structures that can withstand the harsh conditions in space environment. Another goal is to reduce the weight and the launching cost of the structures. A solution to those needs is to integrate fiber reinforced polymers in spacecraft structural components. Radiation shielding is a requirement that has to be met by the materials used to manufacture space structures. Protons are one of the many charged particles that can influence the integrity of materials in space. In the present study three material designs were developed and their ability to shield proton beam irradiation was evaluated. The material designs consist in advanced composite materials (carbon fiber reinforced polymers - CFRPs) that integrate the concept Low Z - High Z - Low Z (tantalum foil) and metallic coatings. Simulations were performed to determine the penetration depth of an ion beam (energy 15 MeV) in the proposed material designs. It was observed that the beam�s penetration depth through a CFRP sample with Ta foil (sample�s thickness 2.08 mm) was about 75% of the sample�s thickness, 58% for CFRP sample with Babbitt coating (sample�s thickness 2.28 mm), 56% for the CFRP sample with Zn coating (sample�s thickness 2.28 mm) and 55% for the CFRP sample with Zn/Monel coating (sample�s thickness 2.28 mm). It seems that the proposed material designs provide ion beam protection similar with an aluminum sample of 2 mm thickness. The experimental procedure confirmed the results obtained from the simulations, all the material designs providing protection in case of proton beam irradiation with an energy of 15.8 MeV.
Experimental Research Using the 3D Printing Technology with Plastic Materials for Prehension Systems Jaws
Authors: Popescu Adrian , Enciu George , Dobrescu Tiberiu , Pascu Nicoleta Elisabeta
Published: January 2020

The studies presented in this article are based on the variation of some constructive parameters on various types of materials for a prehension system jaws. The pneumatic actuation prehension system is part of the structure of a manipulator integrated within a teaching platform for installation. In the tests, the varied parameters were the following: the type of plastic material, the way of printing on the 3D printer bed, the degree of fill (the density) and the geometric shape. The experimental tests have resulted in an optimal version of the prehension system jaws.
PHB/cellulose Fibres Composites Colonization and biodegradation behavior
Authors: Popa Elisabeta Elena , Rapa Maria , Cornea Calina Petruta , Popa Vlad Ioan , Mitelut Amalia Carmen , Popa Ovidiu , Cristea Mihaela Geicu , Popa Mona Elena
Published: January 2020

In this study, newly developed polymeric composites based on poly(3-hydroxybutyrate) (PHB), cellulose fibres (CF) and plasticizer (bis[2-(2-butoxyethoxy)ethyl] adipate) (DBEEA) were subjected both to microorganism�s action in controlled conditions, and to soil�s action by sample burial. The weight loss of PHB based composites at 60 days exposure were determined in comparison with neat PHB. The weight variation for PHB based composites buried in a natural soil at 45 days and 90 days was monitored. DSC-differential scanning calorimetry and SEM -scanning electron microscopy analysis were performed on the tested composites after 90 days of soil burial. It was found that the introduction of cellulose fibres into PHB leads to the increase of biodegradability of composites.
Luminescent Hybrid Materials Based on Curcumin Derivatives Embedded in Palygorskite
Authors: Raduly Monica Florentina , Raditoiu Valentin , Raditoiu Alina , Wagner Luminita Eugenia , Amariutei Viorica , Nicolae Cristian Andi
Published: January 2020

The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.
Bicomponent Hydrogels Based on Methacryloyl Derivatives of Gelatin and Mucin with Potential Wound Dressing Applications
Authors: Serafim Andrada , Olaret Elena , Cecoltan Sergiu , Butac Livia Maria , Balanuca Brindusa , Vasile Eugeniu , Ghica Mihaela , Stancu Izabela Cristina
Published: January 2020

The present paper reports the first attempt to synthesize bicomponent hydrogels based on methacryloyl derivatives of gelatin (GelMA) and mucin (MuMA) with different compositions, with potential as wound dressings. While gelatin is widely investigated and used to fabricate scaffolds and coatings stimulating cell interactions and tissue regeneration, mucin - a macromolecule which covers the wet epithelia - remains yet under exploited as biomaterial. The influence of MuMA content on various parameters such as the affinity for aqueous media, stability in simulated physiologic media and the rheologic behavior was investigated. Also, the preliminary assessment of the drug release potential and biocompatibility were performed. The materials� water uptake capacity and rheologic behavior depend on the pH value of the incubation media, while their composition influences the drug release capacity and cells-scaffold interactions.
Comparative Study Between Polydioxanone Unidirectional Barbed Suture and Absorbable Polyglactin Running Suture in Partial Nephrectomy
Authors: Pirvut Mircea Valentin , Grigore Nicolae , Mihai Ionela , Priporeanu Alexandru Tiberiu , Racheriu Mihaela , Cretu Dan , Teodoru Adrian , Sabau Dan , Mitariu Loredana , Ranga Remus , Manea Marinela Minodora , Hasegan Adrian
Published: January 2020

Combining technological development in the laparoscopic field alongside the increase of surgeon�s experience in partial nephrectomy, have extended the indications of laparoscopic nephron sparing surgery to more complicated cases, increasing the role of suture materials in obtaining a good collecting system closure and hemostasis, with short warm ischemia time and low postoperative complications rate. Suturing materials are continuously developed combining new and unique designs with novel synthetic materials in order to fulfill surgeon�s exigence.
Effect of Graphene Oxide and Graphite on Dry Sliding Wear Behavior of Polyester Composites
Authors: Bastiurea Marian , Dima Dumitru , Andrei Gabriel
Published: January 2020

Graphene oxide and graphite filled polyester composites were prepared by using conventional melt-mixing methods in order to improve tribological performance of polyester. It was investigated friction stability, microhardness, friction coefficient, and specific wear rate of the composites in details. It was found that the presence of graphite and graphene oxide influenced friction coefficient and wear rate of the composites. Graphene oxide decreased wear rate with increasing of test speed and graphite decreased wear rate for composite for all speeds. Tribological performance of the polyester/graphene composites is mainly attributed to bigger thermal conductivity for graphene, which can easily dissipate the heat which appears during the friction process at bigger forces. The positive influence of graphite on coefficient of friction (COF) of the composites is the result of the clivage of graphite layers during the loadings due to van der Waals weak bonds between the graphite layers.
The Mechanical Properties of Some Polymer Composites Based on Natural Rubber
Authors: Stelescu Maria Daniela , Comeaga Daniel , Sonmez Maria , Gurau Dana
Published: January 2020

This paper presents the development and characterization of polymer composites based on natural rubber, crosslinked using two types of vulcanization systems, as follows: the classical method using sulfur and curing accelerators and the method using peroxide in the presence of a polyfunctional monomer - trimethylolpropanetrimethacrylate. The composites were made with 0 parts to 100 parts rubber (phr) and 40 phr filler content. The physical-mechanical characteristics of resulting composites depend on the crosslinking method and on the composition. The mechanical parameters of materials were derived by processing the transmissibility curves, derived for samples with known dimensions and density. The main vibration frequencies and the quality factor, derived in the vicinity of resonances, allow to derive the elasticity and internal damping of materials.
Evaluation of Different Materials Used for Fabrication of Complete Digital Denture
Authors: Andreescu Claudia Florina , Ghergic Doina Lucia , Botoaca Oana , Hancu Violeta , Banateanu Andreea Mariana , Patroi Dan Nicolae
Published: January 2020

Utilization of computer-aided design/computer-aided manufacturing (CAD/CAM) rapidly increases in dental medicine. Making of computer-engineered complete denture is based on scanning of patient data, designing of prosthesis and milling or rapid prototyping. This is digital denture, term that includes innovative devices, software programmes and corresponding materials. Industrially polymerized cross-linked polymethyl methacrylate (PMMA) is the material used for fabrication of digital denture. The aim of this study is to analyze the different cross-linked PMMA used for fabrication of CAD/CAM complete denture.
The Role of the Composite and Biologic Meshes in the Trocar Site Hernia Repair Following Laparoscopic Surgery
Authors: Socea Bogdan , Carap Alexandru , Bratu Ovidiu Gabriel , Diaconu Camelia Cristina , Dimitriu Mihai , Socea Laura Ileana , Bobic Simona , Constantin Vlad Denis
Published: January 2020

The increasing proportion of laparoscopic interventions in the surgical centers has, also, determined an increased incidence of specific complications, such as trocar hernia. Nowadays, there is no unanimously agreed concensus regarding the optimal closure technique of the trocar incision, wether it should include the suture of the aponeurosis or not at the 10 mm ports. There is, also, no consensus regarding the proper surgical technique for the trocar hernia repair- alloplastic or tissue repair technique.The purpose of the study is to present our experience on the alloplastic repair of the trocar hernias. It is a retrospective study that analyzes the results obtained by our clinicalteam regarding the alloplastic repair of the trocar hernias, over a five-year period, between January 2011 and December 2015. The recurrence and the occurrence rates of different complications (seroma, neuroma with postoperative pain, parietal infiltration, infections and mesh rejection), depending on the type of mesh used for the surgical repair,are studied.
Comparative Study on the Efficiency of 2 Different Types of Meshes (Polypropylene and ProGripTM ) in the Surgical Treatment of Incisional Hernias
Authors: Suciu Bogdan Andrei , Halmaciu Ioana , Fodor Decebal , Trambitas Cristian , Ivanescu Adrian , Godja Dumitru , Vunvulea Vlad , Molnar Calin , Brinzaniuc Klara
Published: January 2020

Postoperative eventration is a quite common condition in patients with clinical records of abdominal surgery. The purpose of this study was to investigate the efficacy of use of 2 different types of meshes (Polypropylene mesh and ProGripTM mesh-self-gripping mesh) in the surgical treatment of incisional hernias. In this respect, we conducted a study in which we introduced 128 patients operated for incisional hernias. Patients were divided into 2 lots: group A (102 patients with polypropylene mesh) and group B (26 patients with ProGripTM mesh). From the analysis of the data studied, we noticed that the average duration of surgery and hospitalization for patients with ProGripTM mesh is lower compared to patients with polypropylene mesh. Also, the rate of local postoperative complications was lower when using the ProGripTM mesh (15.38%) than in the case of polypropylene mesh. In conclusion, we can state that the use of the ProGripTM heterologous mesh is beneficial in the surgical treatment of patients with incisional hernias. The major advantage of using this type of mesh is given by a shorter hospitalization period for these patients, as well as by a lower rate of local postoperative complications in these patients.
Comparative Studies on the Thermal Ageing of Some Painting Materials
Authors: Rus Traian , Bors Adriana Mariana , Caramitu Alina Ruxana , Lingvay Iosif , Vaireanu Danut Ionel
Published: January 2020

This paper presents a comparative study with respect to the behavior of some painting materials, used mainly for decorative and protective industrial applications, exposed to a controlled accelerated ageing process by using thermal storage and successive thermal cycles. The evaluation of the structural changes, as well as those concerning the dielectric loss were carried out in a comparative manner, on the initial samples, before any exposure to thermal stresses and during the ongoing process of the thermal treatments applied. As analysis techniques coupled thermal analysis and dielectric impedance spectroscopy have been used. It was found that there is a clear correlation between the structural changes of the investigated materials, particularly in the case of the epoxy materials subjected to the applied thermal treatments and the evolution of the dielectric losses in the material. As a result of these investigations, one may determine the characteristic acceptable zones for the thermal stresses (up to 1300 h of storage and 1500 thermal cycles), anything above these boundaries leading to strong increases in the dielectric losses and hence the deterioration of the materials rendered unfit to be used for the intended purpose.
Innovative Autostatic Laryngeal Stent Used in the Treatment of Laryngeal Stenosis
Authors: Hainarosie Razvan , Ionita Irina Gabriela , Hainarosie Mura , Pietrosanu Catalina , Stefanescu Dragos Cristian , Zainea Viorel
Published: January 2020

Laryngeal stenosis represents a serious and challenging condition in the field of otorhinolaryngology. The management of laryngeal stenosis is performed in multiple stages, and numerous surgeries can be necessary to obtain a favorable outcome. We present a specially designed laryngeal stent suitable for patients with stenosis of the larynx, that can be used after CO2 laser resection. The particular shape of the device, the biocompatible material and the autostatic propriety are some important characteristics that improve the tolerability of patients to the stent. The device has multiple advantages that make it a proper therapy method for selected patients with stenosis of the larynx.
Tailoring Polyelectrolyte Magnetic Capsules
Authors: Stavarache Carmen , Paniwynk Larysa
Published: January 2020

In the second part of this series polyelectrolyte multilayer capsules consisting of 6 bilayers of PAH/PSS and one layer of magnetic iron oxide nanoparticles namely D12, were fabricated. These capsules had their inner core removed once the 12 layers had been formed. The properties of the D12 capsules (mean diameter, concentration, dye intake and iron content) were analysed and compared with previously manufactured capsules which had the core dissolved after only 6 layers of coatings namely D6. The new sets of capsules had a greater capsule diameter, higher dye intake into the core and a higher iron oxide loading into the capsule layers.
Study of Biointegration and Tissue Reaction of Polyethylene Terephtalate 3D and Polypropylene Surgical Meshes in Rat Model
Authors: Benedek Zalan , Bauer Orsolya Hanko , Sorlea Sorin , Coros Marius Florin , Mezei Tibor , Georgescu Rares
Published: January 2020

The aim of this experimental study is to compare the biointegration and tissue response to different surgical mesh types, inserted in various layers of the abdominal wall of Wistar rats. After 30 days, the rats were sacrificed and the meshes were removed en bloc with the subcutaneous tissue, muscular layer and peritoneum. Tissue response (fibrosis, inflammation) was measured using quantitative and semi-quantitative morphometry. We observed that polyethylene terephthalate 3D mesh induces significantly more fibrosis compared to polypropylene mesh and the fibrosis is absent or minimal in case of the control group. Tissue reaction, including fibrosis, is reduced around the polypropylene mesh. We also observed that fibrosis is more intense towards aponeurosis and peritoneum. We can conclude that the 3D mesh shows better biointegration if it is used in proper circumstances. It�s well tolerated by the organism if sutured to the aponeurosis and preferable with monofilament stitches.
Evaluation of Marginal Percolation of the Glass Ionomer Fillings at Temporary Teeth
Authors: Cirdei Mihaela Valentina , Mocuta Daliana , Ogodescu Emilia , Petcu Ana , Lazea Andreea , Todea Carmen
Published: January 2020

The purpose of this in vitro study is to evaluate the marginal percolation-micro leakage by comparing the possible infiltration of ionomer cement filling which was used to restore a class I cavity prepared by classic conventional method - diamond bur versus Er:YAG laser irradiation treatment. Ten molars were included in this study. The molars were random divided in two groups: group 1 - laser treatment and group 2- classic conventional treatments. The teeth were immersed in methylene blue solution for 24 h. Afterwards, the molars were vestibulo-oral sectioned through the centre of each restoration in order to see any signs of marginal percolation. The marginal percolation observed was more significant in conventional preparations group than in laser�s group. The glass ionomer cement remains one of the most adequate restorative materials to be used on deciduous molars when micro infiltration is questionable.
Thermomechanical and Electrical Properties of Fabric Reinforced Laminates with Filled Stratified Epoxy Matrix
Authors: Bunea Marina , Bosoanca Radu , Cojan Adrian , Birsan Iulian Gabriel
Published: January 2020

The thermal coefficient of linear expansion, the electrical conductivity and dielectric permittivity of fabric reinforced hybrid composites with filled stratified epoxy matrix were investigated. The measurements of electrical conductivity and dielectric permittivity had been performed, using standard method regarding electrical resistance and electrical capacity. In order to point out the effect of filler and of the spatial distribution of reinforcement layers, the medial layer of fabric was especially prepared by introducing copper wires in the woven. So, the medial layer is made of different types of tows (carbon, aramid, glass). This attempt is made in order to design a composite able to provide information about its state during various loading. The results showed that the fillers did not improve the electrical parameters of epoxy matrix, but they led to reduce the thermal coefficient of linear expansion. The thermal and electrical behavior of hybrid composites varied in dependence of number of carbon layers and fiber orientation.
On The Strain Sensing of EVA/MWCNT Composite
Authors: Rosculet Razvan Tudor , Stan Felicia , Fetecau Catalin
Published: January 2020

In this paper, the potential of using ethylene-vinyl acetate (EVA) filled with multi-wall carbon nanotubes (MWCNT) composites for strain sensing was investigated. Stress relaxation experiments were conducted on injection-molded samples, and the stress and electrical resistance were measured in situ during the relaxation process. Based on the experimental results, it was found that the electrical resistance of the EVA/MWCNT composite increases with increasing strain, and exponentially decreases with relaxation time, indicating the capacitive behavior of MWCNTs. The maximum electrical conductivity of 7.35�10-4 S/cm was obtained for the EVA/MWCNT composite with 5 wt.% at 180�C, whereas higher piezo-resistive sensitivity was obtained for the composite with 3 wt.%. The electrical percolation threshold was found to increase from 0.223 wt.% at 140�C to 0.994 wt.% at 180�C.
Cavitation Erosion Behavior on Thin Films of Polymer Blends Deposited Over Bronze Surfaces
Authors: Bordeasu Ilare , Circiumaru Adrian , Popoviciu Mircea O. , Lazar Iosif , Badarau Rodica , Groza Ioan
Published: January 2020

The composite materials with polymeric matrix represent a great realization of chemical engineering. Their applications in all the industrial fields are dictated by their chemical, physical and mechanical properties. In the last 50 years the polymeric composite materials received a large use in the protection and repair work of the surfaces in contact with fluid currents of various natures. The scientific researches followed by the industrial use, show that the polymere films with certain composition and properties have an excellent behavior to chemical, abrasive and cavitation erosions. Because the most stressed machine details subjected to cavitation erosions are the blades, runners and impellers of hydraulic machines as well as the ship propellers, researchers are looking for the best polymers to increase the running time, or for the use in covering the zones with shallow erosions, during the repair work. In this direction is oriented also the present research, performed in the Cavitation Laboratory of the Timisoara Polytechnic University. The obtained cavitation erosion for specimens covered with different polymere films is compared with those realized in identical conditions, but for specimens without protection films. The results show that the films assure some increase in the resistance to cavitation erosion but the tested polymer layers have reduced adherence on the metal surface.
Synthesis and Mechanical Properties of Polyurea-Based Hybrid Composites for Ballistic Individual Protection
Authors: Petre Razvan , Zecheru Teodora , Petrea Nicoleta , Ginghina Raluca , Sandu Simona , Muresan Mihaela , Matache Liviu Cristian , Sava Alin Constantin , Neatu Florentina
Published: January 2020

During conûict situations, the combat staff is exposed to a wide variety of aggressions, such as temperature and pressure variations and dynamic impacts (from ammunition or fragments). Textiles used in the manufacture of the military uniforms and devices have always played an important role in defending the military against these hazards, and an adequate level of individual protection equipment is required. In this respect, novel fibre-reinforced polymer composite materials for military application, such as reducing blunt trauma for ballistic protection equipment, have been studied in terms of thermal and mechanical properties and ballistic protection, obtaining very good results.