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In this study, we developed sodium alginate-chitosan hydrogels using a microwave-assisted synthesis method, aligning with green chemistry principles for enhanced sustainability. This eco-friendly approach minimizes chemical use and waste while boosting efficiency. A curcumin:2-hydroxypropyl-β-cyclodextrin complex was incorporated into the hydrogels, significantly increasing the solubility and bioavailability of curcumin. Fourier Transform Infrared Spectroscopy (FTIR) analysis confirmed the structure and successful incorporation of curcumin, in both its pure and complexed forms, into the polymer matrix. Differential scanning calorimetry revealed distinct thermal transitions influenced by the hydrogel composition and physical cross-linking. Hydrogels with higher alginate content had higher swelling ratios (338%), while those with more chitosan showed the lowest swelling ratios (254%). Scanning Electron Microscopy (SEM) micrographs showed a porous structure as well as successful incorporation of curcumin or its complex. Curcumin release studies indicated varying releasing rates between its pure and complexed forms. The chitosan-dominant hydrogel exhibited the slowest release rate of pure curcumin, while the alginate-dominant hydrogel exhibited the fastest. Conversely, for curcumin from the inclusion complex, a higher chitosan proportion led to the fastest release rate, while a higher alginate proportion resulted in the slowest. This study demonstrates that the form of curcumin incorporation and gel matrix composition critically influence the release profile. Our findings offer valuable insights for designing effective curcumin delivery systems, representing a significant advancement in biodegradable and sustainable drug delivery technologies. [ABSTRACT FROM AUTHOR]

Objectives: Oxidative stress, an imbalance between the body's natural antioxidant defenses and the production of reactive oxygen species (ROS), can result in serious oral diseases, including oral cancer, periodontal diseases, and oral lichen planus, through the activation of the redox‐sensitive transcription factors and inflammation. The purpose of this study was to assess the potential effects of a removable complete denture on the levels of oxidative stress markers, such as lipid peroxidation (MDA), advanced oxidation protein products (AOPP), and catalase, and the quantitative expression of the redox‐sensitive transcription factor NF‐κB p65 subunit. Materials and Methods: This interventional follow‐up study enrolled 40 participants of both sexes aged 28–78 years, with a median age of 56 years, where unstimulated saliva was collected before denture placement, immediately after the denture placement, and 24 h, 7 days, and 30 days after the denture placement. The most prominent ROS overproduction was reported on the seventh day (p < 0.05), followed by a significant fall in antioxidative defense. Results: The NF‐κB p65 subunit, whose expression pattern was highest in the same time period on the seventh day, serves as a signaling molecule for redox imbalance due to ROS production. Over the next 30 days, its levels remained moderately increased compared to the basal value, which may influence pro‐inflammatory pathways and the integrity of oral tissue components. These alterations may be induced by the dentures, which can produce high pressures on the supporting tissues or by the synthetic materials used for producing the dentures. Conclusion: Our research may help to clarify the potential pathways by which oxidative stress and redox‐sensitive inflammatory mediators, as well as mechanical and chemical irritants, may serve as risk factors for premalignant lesions in the mouth. Further research on this topic is required to understand the molecular mechanisms behind the relationship between inflammation and oral premalignant lesions caused by mechanical and chemical irritation. [ABSTRACT FROM AUTHOR]

Addition of poly(diallyldimethylammonium chloride) (PDDA) on the performances of urea-formaldehyde (UF) adhesives was evaluated in this work. Three types of UF adhesives were prepared, one without PDDA addition, and two types with PDDA addition of 1 and 3 wt.% per dry UF adhesive mass. These UF adhesive systems were used for producing experimental particleboard panels. The addition of PDDA decreased the thickness swelling of the panel samples, while the internal bond of the particleboards increased significantly only at the highest PDDA content (3 wt.%). Differential scanning calorimetry (DSC) was applied to address the influence of PDDA on UF adhesive curing kinetics. DSC scans were performed in non-isothermal regimes using different heating rates (5, 10, and 20 °C∙min−1). The activation energy (Ea) of the curing reaction showed slightly lower values for the UF adhesive systems containing PDDA. However, the peak temperatures and enthalpy of reaction did not change significantly. The Kissinger-Akahira-Sunose and Friedman iso-conversional methods were applied to investigate the effects of PDDA addition on the UF adhesive curing process.

Liquid-filled hard gelatin capsules may have pertinent advantages both for therapeutic effect and extemporaneous preparations of medicines. Alpha lipoic acid is a substance used in medicines and dietary supplements and there is a need for creating an appropriate formulation which would be suitable for each individual patient or consumer. Based on its biopharmaceutical and physical chemical characteristics, eight different capsule formulations were designed and characterized. Silicon dioxide was added to form a semisolid content and prevent leakage. The formulation filled with alpha lipoic acid solution in polyethylene glycol 400 showed the best performance. Although the addition of silicon dioxide to the formulation with polyethylene glycol 400 led to a change in both flow character and viscosity, the release rate did not show a statistically significant decrease (more than 85% of content was released after 5 min testing). Applied technique is a simple and an appropriate approach for compounding and could be used for other substances with similar properties. [ABSTRACT FROM AUTHOR]

In this study, the influence of nanosilicon(IV)-oxide (with hydrophobic and hydrophilic functionalized surfaces) on the properties of siloxane elastomers was studied. The elastomers were prepared from vinyl and hydrogen oligosiloxanes, while the nanocomposites were obtained by addition of nanofillers at different concentrations (1, 5, 10 and 20 wt%). The chemical structure of the obtained materials was analyzed by Fourier transform infrared spectroscopy. Transmission electron microscopy confirmed good dispersion of the hydrophobic filler within the polymer matrix, while the hydrophilic filler formed a net on the siloxane sample. Type of the filler modification did not affect hardness of the siloxane hybrid materials, while the samples with the highest content of hydrophobic nanosilica have shown the highest value of tensile strength. Influence of the nanosilica type on thermal degradation of elastomeric materials was investigated by using thermogravimetric analysis, while the influence of the fillers on the phase transition temperature was analyzed by differential scanning calorimetry. Lower compatibility of the hydrophobic matrix and hydrophilic filler caused a decrease in the crystalline melting temperature with the lowest value determined for the sample with the highest filler loading. Increase in the nanofiller content resulted in the improved thermal stability of the obtained hybrid materials.

Schizotypy is a construct used to describe a group of persons with symptoms which do not fulfill criteria for schizophrenia, but have some similarities with this complex and heterogeneous psychiatric disorder. ICD-10 describes schizotypy as a state (schizotypal disorder), while DSM-5 labels it as a trait marker (schizotypal personality disorder). Considering how schizotypy encompasses through the normal, subclinical and clinical population, a thorough theoretical understanding of this concept could be helpful in developing measures of assessment. So far, most of the tools for psychometric evaluation of schizotypy have focused only on abnormal personality. The present article focuses on the evolution of the term schizotypy, its current understanding, the possibilities of psychometric assessment in relation to contemporary constructs of personality and on clinical considerations for improved detection and intervention in this field.

This paper presents influence of the type of carbon nanotube functionalization on properties of poly(L-lactide) (PLLA) based nanocomposite materials. For this purpose surface modifications of multi-walled carbon nanotubes (MWCNTs) were performed by chemical and irradiation techniques, while thermo gravimetric analysis, UV-Visible and Fourier-transform infrared (FT-IR) spectroscopies confirmed successful covalent functionalization. Series of PLLA bionanocom-posites with different contents of functionalized MWCNTs (0.7; 1.6; 2.1 wt%), were synthesized via ring-opening solution polymerisation of L-lactide. FT-IR analysis confirmed that grafting of L-lactide, under controlled condition, is possible to perform starting from the surface of functionalized MWCNTs. From differential scanning calorimetry results it was concluded that even low contents of chemically and irradiation functionalized MWCNTs had a significant effect on thermal properties of the prepared nanocomposites, raising the values of melting and glass transition temperatures. Thermogravimetric analysis (TGA) has shown that the degradation onset temperature for composites with chemically functionalized MWCNTs, was much higher than that for the neat poly(L-lactide) sample and composites with irradiation functionalized MWCNTs. Morphology studies by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that poly(L-lactide) covered surfaces and separated functionalized MWCNTs. Good dispersion of carbon nanotubes in polymer matrix enabled conductivity of synthesized materials, as determined by conductivity tests. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 45022 and Grant no. III 45020]

Due to the growing problem caused by waste plastics, academia and industry, invest great dials of efforts to solve this problem and enable the sustainability of polymeric materials. One way, which can successfully solve this problem, is certainly the synthesis of new polymeric materials based on renewable raw materials. Therefore, in this paper, synthesis of polyester based on ricinoleic acid (as well as the methyl ester of ricinoleic acid) is presented, in order to obtain the polyol of the desired molar masses. The polymerization of the ricinoleic acid was performed in the presence of diethylene glycol, as an initiator, and titanium isopropoxide, as a catalyst. By analyzing the molar masses of the obtained polyesters, it has been confirmed that the control of the molecular weight of the polyricinoleic acid can be successfully accomplished by the addition of a precisely determined amount of diethylene glycol, thus enabling in this way the synthesis of polyols of desired properties. The molecular structure of the synthesized polyols is confirmed by FTIR and NMR spectroscopy. The analysis of the thermal properties showed that the glass transition temperatures of the synthesized polyols range from -70 to -80ºC, which makes it possible to apply these materials in low-temperature applications. The slight increasment of thermal stability is observed, only with the increasment of molecular weight, which was confirmed by TG analysis. The viscosity measurement results confirmed that as the molar weight of synthesized polyester increases, the viscosity of the samples also increases.

Purpose: To evaluate the influence of group and individual education on shade matching quality using a visual color competency test to match shade tab pairs from two Vita classical A1-D4 shade guides. Methods: 60 dental students, 21-25 years old (39 females, 21 males) participated in the study. All participants passed a color deficiency test before the experiment. The examination was voluntary and approved by the corresponding Ethics Committee. Students were randomly divided into three groups (n=20): one control group, NE (no education) and two experimental groups - GE (group education) and IE (individual education). The study was performed in three phases. In the "before" (B - Phase 1) and "after" (A - Phase 3) phase, all groups had to match 16 pairs of tabs from two Vita classical A1-D4 shade guides, with the shade designations hidden by custom letter markings. All tabs were mixed on a gray surface illuminated by color-correcting light. In Phase 2 (between B and A), GE had only group education, while IE received additional individual education and training. The control group did not participate in Phase 2. Means and standard deviations were calculated, and differences were compared using the one-way ANOVA, ANCOVA test, and Student t-test for dependent samples (α= 0.05). Results: The NE group matched 10.3 (3.2) and 10.4 (2.9) tab pairs in the before and after phases, respectively. Corresponding results for GE were 11.1 (2.2) and 14.4 (1.9) and 9.5 (3.6) and 15.0 (1.5) for IE, respectively. In Phase 1 (B), no statistically significant difference was recorded among the groups (P= 0.260). The experimental groups achieved a statistically significant improvement compared with the control group in Phase 3 (A) (P< 0.001). Both experimental groups achieved statistically significant improvement within the group after education, GE (P< 0.001) and IE (P< 0.001). Within the limitations of this study, it was concluded that both experimental groups had statistically significant progress in shade matching. The group that received individual education (IE) made statistically significant progress compared with the group that received group education (GE). No statistically significant difference was found in the results of the control group between Phase 1 and Phase 3 of the study. [ABSTRACT FROM AUTHOR]

Objective: Disintegration is a recently proposed broad, trait‐like reconceptualization of the proneness to psychotic‐like experiences/behaviors. Methods: We tested the assumption that the 6‐factor model (Five‐Factor traits plus Disintegration) was the most adequate one and that it was invariant across clinical and non‐clinical populations. The clinical sample (n = 161) consisted of patients who had at least one psychotic episode, duration of illness less than 10 years, currently in remission. The general population (n = 409) was matched with the patient sample by age, gender, and education. NEO PI‐R and DELTA were used to measure personality dimensions in both samples. Invariance of one to six‐factor solutions was tested by Exploratory Structural Equation Modeling. Results: We found that: (a) several criteria for deciding on the number of factors to retain converged to the conclusion that the assumed 6‐factor model was the most adequate one, (b) the assumed factorial structure appeared to satisfy the criteria for the scalar invariance across the two samples, (c) all nine Disintegration subdimensions separated from the Big Five, forming the Disintegration factor, and (d) Disintegration was unrelated to Openness. Conclusion: The Big Five personality structure—complemented with disintegration—was invariant across individuals from the general population and patients with psychosis. [ABSTRACT FROM AUTHOR]

Food packaging industry presents one of the fastest growing industries nowadays. New trends in this industry, which include reducing food as well as packaging waste, improved preservation of food and prolonged shelf-life together with substitution of petrochemical sources with renewable ones are leading to development of this industrial area in diverse directions. This multidisciplinary challenge is set up both in front of food and material scientists. Nanotechnology is recently answering to these challenges, with different solutions-from improvements in materials properties to active packaging solutions, or both at the same time. Incorporation of nanoparticles into polymer matrix and preparation of hybrid materials is one of the methods of modification of polymer properties. Nano scaled materials with antimicrobial properties can act as active components when added into polymer, thereby leading to prolonged protective function of pristine food packaging material. This paper presents a review in the field of antimicrobial nanomaterials for food packaging in turn of technology, application and regulatory issues.

Properties of poly (lactic acid) (PLA) and its nanocomposites, with silica nanoparticles (SiO2), as filler were investigated. Neat PLA films and PLA films with different percentage of hydrophobic fumed silica nanoparticles (0.2, 0.5, 1, 2, 3 and 5 wt. %) were prepared by solution casting method. Several tools were used to characterize the influence of different silica content on crystalline behavior, and thermal, mechanical and barrier properties of PLA/SiO2 nanocomposites. Results from scanning electron microscope (SEM) showed that the nanocomposite preparation and selection of specific hydrophobic spherical nano filler provide a good dispersion of the silica nanoparticles in the PLA matrix. Addition of silica nanoparticles improved mechanical properties, the most significant improvement being observed for lowest silica content (0.2wt.%). Barrier properties were improved for all measured gases at all loadings of silica nanoparticles. The degree of crystallinity for PLA slightly increased by adding 0.2 and 0.5 wt. % of nano filler. [Projekat Ministarstva nauke Republike Srbije, br. III46001]

Dental crowding can be defined as a lack of space in dental arch for the proper placement of all teeth. The aim of this study was to determine prevalence of maxillary and mandibular anterior crowding at school children from Niš and surroundings. Material and methods: The study sample comprised 2027 elementary school children (1025girls, 1002 boys). We have analyzed the presence and extent of maxillary and mandibular anterior crowding (mild, moderate and severe ). Results: The percentage of maxillary anterior crowding for girls (73,55%) was greater than that for boys (65,65%). The most common was a mild crowding (37,58% girls, 42,35% boys), then moderate crowding (35,28% girls, 35,22% boys) and the lowest percentage had severe crowding (27,14% girls, 22,43% boys).The percentage of mandibular anterior crowding for girls (78,54%) was greater than that for boys (76,55%). The most common was a mild crowding (40,37% girls, 39,95% boys), then moderate crowding (33,78% girls, 36,25% boys) and the lowest percentage had severe crowding (25,84% girls, 23,85% boys). Conclusion: It is important to have knowledge about the incidence of dental crowding in school children, that we can start with treatment on time.

The growing body of evidence on the dimensional classification of personality disorders (PD) has resulted in its acceptance in the ICD-11 classification, which abolished categories and retains only a general description of PD. Specifying the type of PD is optional, and the suggested domains represent maladaptive variants of the five-factor model of personality (FFM). The aim of our study was to explore the existence of a joint structure between maladaptive and normal personality traits, and to investigate how these structures are integrated. The study included 223 patients who had been diagnosed with PD and completed the Structured Clinical Interview for DSM-5 Personality Disorders and the NEO Personality Inventory-Revised (NEO-PI-R). To determine the degree of overlap between PD domains and NEO PI–R scales, a canonical analysis of covariance was conducted. Our findings showed a relationship between the internalizing PD spectrum (consisting of avoidant, dependent, and borderline traits with detached and anankastic traits) and high neuroticism, low conscientiousness, and moderately low agreeableness and extroversion, suggesting the existence of a broad personality disorder factor. However, the internalizing dimensions exhibited a more pronounced effect within this construct. Furthermore, we identified a second function that demonstrated a link between the externalizing PD spectrum (including narcissistic, histrionic, and antisocial traits) and high extraversion, high openness, and low agreeableness, suggesting the existence of an externalizing factor. Overall, our findings provide evidence for a joint structure of maladaptive and normal personality traits in a sample of personality disorders and emphasize the importance of integrating the FFM model in PD evaluation in clinical practice, suggesting that differentiating between major subgroups could assist in adjusting therapeutic approaches. [ABSTRACT FROM AUTHOR]