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An active packaging based on the composite film was developed by incorporation of oregano oil as an antimicrobial agent into a cellulose acetate/polycaprolactone diol blend (CA/PCL-diol). A novel plasticizer based on polyethylene terephthalate (PET) glycolysis product (bis(hydroxyethyl terephthalate)) and tartaric acid was synthesized and its influence on the structural, surface, mechanical, barrier, and thermal properties were investigated. The obtained results have shown that plasticizer also has a compatibilizing effect, improving the miscibility of polymers in a blend. A sample with the optimal amount of plasticizer (30 wt%), as well as the best mechanical and barrier properties, was used for the preparation of series with different amounts of oregano oil (3, 6, and 9 wt%). The synthesized azo dye—5-(4-bromo-phenyl azo)-3-amido-6-hydroxy-4-methyl-2-pyridone, soluble in acetone, as well as a blend and plasticizer, has been shown as an adequate one for this composition, due to its ability to achieve a good pigmentation in a low amount (0.3 wt% per polymer blend weight), to absorb UV light, and decrease the aging of the material. Contemporary lifestyle has imposed a need for ready-to-eat (RTE) meals which saves consumers time. RTE food packaging should meet certain requirements such as the ability to prolong shelf-life and preserve the freshness of the food product, and at the same time to make a minimal amount of waste after usage, considering the fact that it is mostly single-use plastic food packaging. Optimal mechanical properties, biodegradability, and additional functions make these films suitable for the packaging of ready-to-eat (RTE) food such as fresh salad.

Microfluidics is a science and technology. The scientific aspect deals with the behaviour of fluids in the channels of the micrometre order because the behaviour of fluids on the microscale differs drastically in relation to the macroscale. The technological aspect deals with the production and miniaturization of devices, which consist of microchannels or even nanochannels. Unlike the miniaturization of integrated circuits and microelectromechanical devices, in which the whole device is scaled, for microfluidics only the scaling of the space through which the fluid moves is important. The sensitivity of the device is determined by the minimum amount of microfluid that can be used. The fabrication of microfluidic devices is still far from mass production for which there is already a need. Current fabrication technologies are concentrated on the production of laboratory prototypes or have unsatisfactory characteristics for biomedical applications. The development of new technology that can reconcile mass production and biomedical compatibility is the main thread of this thesis. The use of microfluidic devices in biomedicine with an emphasis on material testing as well as personalization and precise dosing of therapy is one of the hot topics today. In precision dosing, one of the most important roles is played by the mixer or micromixer, because the precision and agility of the entire system depend on its precision. The construction of micromixers is a current topic in today's research laboratories., Mikrofluidika predstavlja nauku i tehnologiju. Naučni aspekat se bavi ponašanjem fluida u kanalima reda mikrometra jer se ponašanje fluida na mikroskali drastično razlikuje u odnosu na makroskalu. Tehnološki aspekat se bavi proizvodnjom i minijaturizacijom uređaja, koji se sastoje od mikrokanala ili čak nanokanala. Za razliku od minijaturizacije integrisanih kola i mikroelektromehaničkih uređaja, kod kojih se ceo uređaj skalira, za mikrofluidiku važno je samo skaliranje prostora kroz koji se fluid kreće. Osetljivost uređaja je određena najmanjom količinom mikrofluida koji se može koristiti. Fabrikacija mikrofluidnih uređaja još je daleko od masovne proizvodnje za kojom već postoji potreba. Aktuelne tehnologije fabrikacije su prilagođene laboratorijskim prototipovima ili imaju nezadovoljavajuće karakteristike za biomedicinsku primenu. Razvoj nove tehnologije koja može da pomiri masovnu proizvodnju i biomedicinsku kompatibilnost predstavlja glavnu nit ove teze. Primena mikrofluidnih uređaja u biomedicini sa akcentom na ispitivanje materijala kao i personalizaciju i precizno doziranje terapije jedna je od najaktuelnijih tema današnjice. Kod preciznog doziranja jednu od važnijih uloga igra mikro mešač odnosno mikromikser, jer od njegove preciznosti zavisi preciznost i agilnost čitavog sistema. Konstrukcija mikro mešača je aktuelna tema u današnjim istraživačkim laboratorijama.

The aim of the present study was to investigate the possibility of estimating crown formation times of immature deciduous teeth and age at death in Neolithic newborns. In the Neolithic-Mesolithic transition, the health of the population deteriorated. Leaving the intrauterine environment for the newborn is the first obstacle in the process of adaptation and survival in the outside world. The fetus is protected by the mother's immune system and receives the necessary nutrients through the umbilical cord, but external factors indirectly affect its development. At birth deciduous teeth are not fully formed and are only partially mineralized. Variations in the rhythmic activity of ameloblasts and the secretion of the enamel matrix lead to the formation of incremental lines in the enamel. The sample consisted of unerupted deciduous teeth removed from the baby jaws from Neolithic archaeological graves, LepenskiVir Serbia. The skeletal age of the babies was from 38 to 40 gestational weeks. The daily enamel apposition rate was obtained for each tooth. The age of individuals was estimated using crown formation time. The average value of daily secretion rates for the primary teeth from the Neolithic age was 3.78 mm. There was no statistically significant difference in age at death determined by skeletal age assessment and crown formation time. Three babies were born preterm. The results of the present study show that the calculation of the time required for the formation of deciduous tooth enamel is applicable to archaeological samples of newborns. The age estimation using crown formation time together with the analysis of other anthropological parameters, can contribute to a more accurate determination of neonatal death in anthropological, archaeological and forensic contexts.

The aim of the present study was to investigate the possibility of estimating crown formation times of immature deciduous teeth and age at death in Neolithic newborns. In the Neolithic-Mesolithic transition, the health of the population deteriorated. Leaving the intrauterine environment for the newborn is the first obstacle in the process of adaptation and survival in the outside world. The fetus is protected by the mother's immune system and receives the necessary nutrients through the umbilical cord, but external factors indirectly affect its development. At birth deciduous teeth are not fully formed and are only partially mineralized. Variations in the rhythmic activity of ameloblasts and the secretion of the enamel matrix lead to the formation of incremental lines in the enamel. The sample consisted of unerupted deciduous teeth removed from the baby jaws from Neolithic archaeological graves, LepenskiVir Serbia. The skeletal age of the babies was from 38 to 40 gestational weeks. The daily enamel apposition rate was obtained for each tooth. The age of individuals was estimated using crown formation time. The average value of daily secretion rates for the primary teeth from the Neolithic age was 3.78 mm. There was no statistically significant difference in age at death determined by skeletal age assessment and crown formation time. Three babies were born preterm. The results of the present study show that the calculation of the time required for the formation of deciduous tooth enamel is applicable to archaeological samples of newborns. The age estimation using crown formation time together with the analysis of other anthropological parameters, can contribute to a more accurate determination of neonatal death in anthropological, archaeological and forensic contexts.

The research of human induced tooth marks on bone surface represents a promising field of investigation of high interest for archaeologists. The aim of this study was to address the issue of equifinality of tooth marks recognition and analysis using experimental setup involving permanent teeth. Five volunteers mouthed and chewed fresh metatarsal bovine bone. A total of gt 2000 marks were recorded and the type, geometry and metrics reported. Differences between tooth type and intensity level employed for marks formation were also described. The obtained data may support the identification and recognition of human tooth marks in the archaeological context.

Background: All objects put into a child's mouth could be hazardous in terms of trauma and toxic substance exposure. The aims of this study were to evaluate morphological characteristics of the primary teeth bite marks inflicted on various materials and to assess material wear using experimental model. Methods: Bite marks were analyzed on five materials: rubber, plastic, foil, wood, and silicone. In order to mimic children mouthing behavior an experimental setup has been designed using primary teeth placed in dentures and children's equipment specimens. Results: Deciduous teeth make visible and recognizable traces when using physiological forces on all investigated materials. The most significant material loss was revealed in silicone samples, but it has been observed in all material groups, while mouthing with incisors using higher mastication forces were identified as significant predictors for material wear. There were no significant differences between type, species, and morphological-morphometric characteristics of the bite marks which are made by incisors, canines, and molars. Conclusions: In the range of physiological bite forces, deciduous teeth lead to wear of material from which toys are made while the analysis of bite marks in children equipment could give some information regarding the risk of trauma and exposure.

Purpose: The purpose of this study was to quantify the elastic properties and evaluate microscopical features of raw and boiled metatarsal bovine bone. Methods: The elastic modulus, hardness and microscopic surface of raw and cooked bovine metatarsal bone have been investigated using nanoindentation, SEM/EDX and Panasis microscope. Results: Regarding raw bovine bone, the average elastic modulus was 30.515 +/- 6,769 GPa, while the average hardness was 0.5683 +/- 0.211 GPa. When it comes to boiled bone corresponding values were 22.298 +/- 7.0303 GPa and 0.408 +/- 0.199 GPa, respectively. The values for investigated parameters were significantly higher (p lt 0.05) in raw bone specimens. Elastic modulus significantly correlated with hardness (p lt 0.05). EDX analysis revealed significant decrease in wt% of oxygen in boiled samples (p lt 0.05) No significant differences could be observed in SEM images particularly when analysing in smaller magnifications. Using higher magnification, additional branching of the existing voids as well as discrete reorganization and smoother edges of nutrient canals could be observed. The surface of boiled specimens was without the presence of crusts and layering, and no microscopical evidence of structural damage could be observed. Conclusions: This study provides detailed analysis of hardness, elastic modulus of raw and cooked bovine bone and their relation and changes during exposure to temperature. These results of elastic moduli and hardness could be comparable to similar studies of bovine and human bone tissue, but the careful analysis of experimental design, type of the bone as well as limitations of the employed techniques must be carried out before interpolation of the results to other theoretical, clinical, biomaterial and archeological studies.

Around 8000 years ago, throughout the Neolithic world a new type of artefact appeared, small spoons masterly made from cattle bone, usually interpreted as tools, due to their intensive traces of use. Contrary to those interpretations, the small dimensions of spoons and presence of intensive traces of use led us to the assumption that they were used for feeding babies. In order to test that assumption we compared 2230 marks on three spoons from the Neolithic site of Grad-Starcevo in Serbia (5800-5450 cal BC) with 3151 primary teeth marks produced experimentally. This study has shown that some of the marks on spoons were made by primary teeth, which indicate their usage in feeding babies. The production of a new type of artefact to feed babies is probably related to the appearance of a new type of weaning food, and the abundance of spoons indicates that new baby gruels became an important innovation in prehistoric baby-care.

Around 8000 years ago, throughout the Neolithic world a new type of artefact appeared, small spoons masterly made from cattle bone, usually interpreted as tools, due to their intensive traces of use. Contrary to those interpretations, the small dimensions of spoons and presence of intensive traces of use led us to the assumption that they were used for feeding babies. In order to test that assumption we compared 2230 marks on three spoons from the Neolithic site of Grad-Starcevo in Serbia (5800-5450 cal BC) with 3151 primary teeth marks produced experimentally. This study has shown that some of the marks on spoons were made by primary teeth, which indicate their usage in feeding babies. The production of a new type of artefact to feed babies is probably related to the appearance of a new type of weaning food, and the abundance of spoons indicates that new baby gruels became an important innovation in prehistoric baby-care.

The research of human induced tooth marks on bone surface represents a promising field of investigation of high interest for archaeologists. The aim of this study was to address the issue of equifinality of tooth marks recognition and analysis using experimental setup involving permanent teeth. Five volunteers mouthed and chewed fresh metatarsal bovine bone. A total of gt 2000 marks were recorded and the type, geometry and metrics reported. Differences between tooth type and intensity level employed for marks formation were also described. The obtained data may support the identification and recognition of human tooth marks in the archaeological context.

Purpose: The purpose of this study was to quantify the elastic properties and evaluate microscopical features of raw and boiled metatarsal bovine bone. Methods: The elastic modulus, hardness and microscopic surface of raw and cooked bovine metatarsal bone have been investigated using nanoindentation, SEM/EDX and Panasis microscope. Results: Regarding raw bovine bone, the average elastic modulus was 30.515 +/- 6,769 GPa, while the average hardness was 0.5683 +/- 0.211 GPa. When it comes to boiled bone corresponding values were 22.298 +/- 7.0303 GPa and 0.408 +/- 0.199 GPa, respectively. The values for investigated parameters were significantly higher (p lt 0.05) in raw bone specimens. Elastic modulus significantly correlated with hardness (p lt 0.05). EDX analysis revealed significant decrease in wt% of oxygen in boiled samples (p lt 0.05) No significant differences could be observed in SEM images particularly when analysing in smaller magnifications. Using higher magnification, additional branching of the existing voids as well as discrete reorganization and smoother edges of nutrient canals could be observed. The surface of boiled specimens was without the presence of crusts and layering, and no microscopical evidence of structural damage could be observed. Conclusions: This study provides detailed analysis of hardness, elastic modulus of raw and cooked bovine bone and their relation and changes during exposure to temperature. These results of elastic moduli and hardness could be comparable to similar studies of bovine and human bone tissue, but the careful analysis of experimental design, type of the bone as well as limitations of the employed techniques must be carried out before interpolation of the results to other theoretical, clinical, biomaterial and archeological studies.

Background: All objects put into a child's mouth could be hazardous in terms of trauma and toxic substance exposure. The aims of this study were to evaluate morphological characteristics of the primary teeth bite marks inflicted on various materials and to assess material wear using experimental model. Methods: Bite marks were analyzed on five materials: rubber, plastic, foil, wood, and silicone. In order to mimic children mouthing behavior an experimental setup has been designed using primary teeth placed in dentures and children's equipment specimens. Results: Deciduous teeth make visible and recognizable traces when using physiological forces on all investigated materials. The most significant material loss was revealed in silicone samples, but it has been observed in all material groups, while mouthing with incisors using higher mastication forces were identified as significant predictors for material wear. There were no significant differences between type, species, and morphological-morphometric characteristics of the bite marks which are made by incisors, canines, and molars. Conclusions: In the range of physiological bite forces, deciduous teeth lead to wear of material from which toys are made while the analysis of bite marks in children equipment could give some information regarding the risk of trauma and exposure.

Purpose: The objective was to assess the effect of fissure depth and enamel surface preparation protocols on penetration of resin-based, giomer and glass-ionomer fissure sealants. Materials and Methods: Ninety extracted third molars were assigned into three groups according to the material used. All three groups were subsequently divided depending on tooth preparation: no pretreatment or surface preparation with 10% polyacrylic acid, 37% phosphoric acid, or self-etching adhesive. In addition, Er,Cr:YSGG laser or air abrasion were employed in all subgroups. The penetration was evaluated using scanning electron microscopy. Results: The groups that were pretreated with an appropriate acid resulted in superior penetration of glass-ionomer and resin-based sealants when compared with other surface preparation protocols (p lt 0.05). The exception was teeth treated with both air abrasion and acid etching. Both preparation protocol and fissure depth significantly affected the sealant penetration (p lt 0.05), but fissure depth had a greater impact on fissure penetration than did enamel surface pretreatment. Conclusion: All investigated materials exhibit similar properties regarding sealant penetration. Penetration of a fissure sealant is significantly influenced by the fissure depth. In regard to enamel surface preparation protocol, a pretreatment with phosphoric acid in resin-based and polyacrylic acid in glass-ionomers appears to be essential in obtaining the adequate penetration of a sealing material.

Purpose: The purpose of this study was to quantify the elastic properties and evaluate microscopical features of raw and boiled metatarsal bovine bone. Methods: The elastic modulus, hardness and microscopic surface of raw and cooked bovine metatarsal bone have been investigated using nanoindentation, SEM/EDX and Panasis microscope. Results: Regarding raw bovine bone, the average elastic modulus was 30.515 +/- 6,769 GPa, while the average hardness was 0.5683 +/- 0.211 GPa. When it comes to boiled bone corresponding values were 22.298 +/- 7.0303 GPa and 0.408 +/- 0.199 GPa, respectively. The values for investigated parameters were significantly higher (p lt 0.05) in raw bone specimens. Elastic modulus significantly correlated with hardness (p lt 0.05). EDX analysis revealed significant decrease in wt% of oxygen in boiled samples (p lt 0.05) No significant differences could be observed in SEM images particularly when analysing in smaller magnifications. Using higher magnification, additional branching of the existing voids as well as discrete reorganization and smoother edges of nutrient canals could be observed. The surface of boiled specimens was without the presence of crusts and layering, and no microscopical evidence of structural damage could be observed. Conclusions: This study provides detailed analysis of hardness, elastic modulus of raw and cooked bovine bone and their relation and changes during exposure to temperature. These results of elastic moduli and hardness could be comparable to similar studies of bovine and human bone tissue, but the careful analysis of experimental design, type of the bone as well as limitations of the employed techniques must be carried out before interpolation of the results to other theoretical, clinical, biomaterial and archeological studies.

Changes in composition and new material characteristics require verification in clinical and experimental studies. Investigating glass-ionomer cements under laboratory conditions encounters problems in interpreting the results and in comparing them with other types of materials tested in the same way. As the connection between the glass-ionomer cements and the dental tissues is delicate, it is often the case that the impact of fractures and other artifacts is either underestimated or over-dimensioned when interpreting the results. A critical review was performed, with defining the main problems regarding the usage of SEM, EDX and nanoindentation techniques in glass-ionomer based materials evaluation.

Background: All objects put into a child's mouth could be hazardous in terms of trauma and toxic substance exposure. The aims of this study were to evaluate morphological characteristics of the primary teeth bite marks inflicted on various materials and to assess material wear using experimental model. Methods: Bite marks were analyzed on five materials: rubber, plastic, foil, wood, and silicone. In order to mimic children mouthing behavior an experimental setup has been designed using primary teeth placed in dentures and children's equipment specimens. Results: Deciduous teeth make visible and recognizable traces when using physiological forces on all investigated materials. The most significant material loss was revealed in silicone samples, but it has been observed in all material groups, while mouthing with incisors using higher mastication forces were identified as significant predictors for material wear. There were no significant differences between type, species, and morphological-morphometric characteristics of the bite marks which are made by incisors, canines, and molars. Conclusions: In the range of physiological bite forces, deciduous teeth lead to wear of material from which toys are made while the analysis of bite marks in children equipment could give some information regarding the risk of trauma and exposure.

The aim of this work was to evaluate the nano-mechanical properties of glass ionomer materials, the ion concentrations at the surfaces in relation to the storage media and the pH environments using a scanning electron microscope with an energy-dispersive spectrometer (SEM/EDX). the glass-ionomer-based materials, Fuji Triage (FT), Fuji VIII (FVIII). Fuji IX GP (FIX), were analyzed. The sample comprised 45 cured cement disks. Five specimens of each tested material were placed in 3 storage solutions (saline, acidic solution with pH of 5.5, NaF solution with 0.05 % of fluoride). Nano-indentations were performed with a force up to 30 mN, penetration depths of 2500-2700 nm for 1 d and 21 d after setting. The EDX evaluation was carried out for each experimental disk, identifying the ions: O, Al, Sr, Si, F,Na, P, Ca. The level of significance was placed at p lt 0.05.The highest fluoride proportion at the specimen surface was recorded in the FT material. FT also exhibited the lowest fluoride ions content when stored in low-pH environments compared with the other tested materials (p lt 0.05). The surface hardness of the tested materials decreased from 1.377 GPa (in saline) to 0.03 GPa (in acid). The Young's modulus varied from 14.35 GPa to 0.112 GPa, depending on the material type (Fuji VIII>Fuji IX>FT) (p lt 0.001) and the storage media (p lt 0.001). Both the mechanical and cariostatic surface properties of commercially available glass ionomer materials are affected by the storage media.