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Background Orthodontic treatment is a long process that requires patient cooperation. Risks of side effects such as caries formation, periodontal problems, and root resorption increases as well as problems in patient cooperation arises with longer treatments. Several different techniques were developed that may shorten the treatment time. Objective The aim of this study was to evaluate the effectiveness of micro-osteoperforations (MOPs) performed during the alignment stage. Trial design Randomized controlled trial. Methods Twenty-eight subjects who had crowding in the mandibular arch were included in the study. The first group (4 boys and 10 girls, mean age = 17.21 ± 3.76 years) was treated with MOP (MOP) and the second group (8 boys and 6 girls, mean age = 15.29 ± 1.77 years) was treated without MOP (control). Cephalometric variables, periodontal parameters, Little irregularity index, alignment duration, patient satisfaction, and ease of operation were evaluated. The level of statistical significance was P ≤ 0.05. Results Alignment duration was shorter (P = 0.000) in the MOP group (105.57 ± 18.34 days) compared to control group (135.86 ± 15.12 days). Alleviating of the crowding was more in the MOP group, compared to the control group in all time points. The pain level in the MOP group in the first appointment was higher compared to control group (P = 0.002). There was no significant difference between the groups in cephalometric parameters. Higher increases were found for gingival index (P = 0.008) and bleeding index (P = 0.039) in the control group compared to MOP group at the end of treatment Limitations The study was a single-centre study. Conclusion Alignment stage was shortened with MOP application. There was no difference between groups for patient satisfaction and pain level except for the first appointment. No difference was observed between the groups regarding cephalometric values. Clinically insignificant inflammation was observed in periodontal tissues for both groups. Registration This study was registered at the Clinical Trials Registry (ClinicalTrials.gov NCT03652454).

Over the last decade, it has become clear that the pollution by plastic debris presents global societal, environmental, and human health challenges. Moreover, humans are exposed to plastic particles in daily life and very limited information is available concerning human health, especially interactions with biological fluids. Therefore, the aim of this study is to investigate the interaction of plastic particles with simulated biological fluids (e.g., artificial saliva, artificial lysosomal fluid, phagolysosomal simulant fluid, and Gamble's solution) using various exposure stages (2 h to 80 h) and the effect of plastic particles on the formation of Staphylococcus aureus biofilms under simulated biological conditions. The plastic particles incubating various simulated biological fluids were characterized using surface functional groups, zeta potentials, and elemental composition. The results indicated that functional group indices (C-O, C = O, C-H, C = C, C-N, S = O, and OH) decreased compared to the control group during the incubation periods, except for the hydroxyl group index. The FTIR results showed that the hydroxyl group formed with the artificial lysosomal fluid, the phagolysosomal simulant fluid, and Gamble's solution. With the impact of the declining functional groups, the zeta potentials were more negative than in the control. Moreover, EDX results showed the release of the components in the particles with the interaction of simulated biological fluids as well as new components like P and Ca introduced to the particles. The biofilms were formed in the presence of nanoplastic particles under both controlled conditions and simulated biological conditions. The amount of biofilm formation was mainly affected by the surface characteristics under simulated biological conditions. In addition, the biofilm characteristics were influenced by the O/C and N/C ratios of the plastic particles with the impact of simulated biological fluids.

Pollution by plastics and antibiotics are emerging issues in the areas of the environment and human health. In recent years, several studies have documented the widespread occurrence of plastic particles in various environmental, as well as human, systems, and much research has focused on possible interactions of contaminants with microplastics. Thus, the co-occurrence of plastics and antibiotics has caused another global problem for the environment and human health. Therefore, we focused on the current knowledge in the field of the co-occurrence of plastics and antibiotics to summarize the available studies. In this review, categorization of the topics, contaminants details, such as polymer type, size and source, antibiotic type, and other experimental parameters were summarized and discussed. This study indicated that the sorption of antibiotics on plastics, antibiotic susceptibility in the presence of plastics, and antibiotic resistance gene onto plastics were the most frequently examined categories in this field. Moreover, the variability in the procedures and the processes, and the heterogeneity data of reporting between different studies on similar topic make it difficult to bring all results together and produce a comprehensive picture of the current knowledge. Therefore, it is suggested that further research should be done using this systematic study.

In this study, we reported the interaction between plastic traces and vital amino acids (L-homocysteine, L-valine, and L-lysine) in an aqueous system and characterized this interaction by Fourier transform infrared spectroscopy and Scanning electron microscopy with energy-dispersive X-ray spectroscopy studies. Bacterial activity and biofilm formation and their characteristics of non-treated and amino acid-treated plastic traces was tested against the Staphylococcus aureus bacterial pathogen. The surface results showed that the carbonyl groups and oxygen to carbon ratios were increased, and the attachment of nitrogen- and sulfur-related substances on the plastic surface occurred by the homocysteine over time. Plastic traces showed particle surface deformation using the main functional groups (e. g. alkyne-alkene, vinyl, secondary alcohols, alkane-methylene) with the increasing lysine treatment; however, decreased oxygen to carbon ratio showed particle anti-aging. The most common functional groups were primarily deformed with the longer exposure to valine. The bacterial activity results showed that the Staphylococcus aureus activities were not primarily changed by the amino acid treatment compared to the non-treated plastic traces. However, amino acid treated plastic traces induced the biofilm formation and its characteristic due to surface deformation of functional groups and alteration of new substances on plastic traces.

In the last decade, a great deal of research has focused on the determination of potential toxic metals in indoors due to an important source of the toxicity and health risks. The previous studies have commonly focused determination of total concentration of metals and identification the microorganisms in dust. On the other hand, determination bio-relevant forms (e.g., inhalable) of metals instead of total contents, examination the behavior of microorganism under these bio-relevant conditions and revealing the interaction between metals and pathogens is vital and necessary for realistic approach. However, previous studies have been ignored these topics in this field. Therefore, the present study aimed to (i) investigate metals in household dusts extracted in simulated body fluids by inhalation, (ii) examine the culturable pathogen responses in the presence of household dusts extracted in simulated body fluids, and (iii) assess their relations and risks using the model approaches by inhalation. Here, 25 household-dusts were extracted in four simulated body fluids to determine bio-relevant forms of metals (specifically using inhalation fluids). Moreover, four clinically important pathogens were incubated in the presence of household-dusts extracted in simulated body fluids. The activity, biofilm, biochemical and oxidative responses of pathogens were measured following household-dust exposures. Afterward, the relationship between metals and pathogens responses were evaluated, and model and derived approaches were used for risk assessments of metals and pathogens. The higher daily intake metal values obtained in artificial lysosomal fluid fraction of household dust that mimicking the inflammatory condition compared to other body fluids. The highest risk of the pathogens originated by biofilm formation.

Introduction The purpose of this prospective clinical trial is to evaluate the changes of soft tissues and designate the esthetic perceptions of children with Class II malocclusion after Herbst appliance therapy and maxillary molar distalization using stereophotogrammetry. Methods Thirty patients were allocated either to Herbst (6 boys and 9 girls; mean age = 11.60 ± 0.82 years) or distalization (4 boys and 11 girls; mean age = 11.46 ± 1.30 years) groups. Dentoskeletal and soft-tissue treatment changes were examined objectively by cephalometric analysis and stereophotogrammetry, respectively. Pre- and posttreatment profile views were evaluated subjectively by orthodontists and laypeople using the 7-point Likert scale. Intra- and intergroup comparisons for the repeated measurements were performed with 2-way variance analysis. Bonferroni test was used for multiple comparisons (P ≤0.05). Results Greater skeletal changes were observed in the Herbst group than in the distalization group. Maxillary incisor retrusion and mandibular incisor protrusion were observed in the distalization and Herbst groups, respectively. Stereophotogrammetric measurements showed that mandibular body length and lower and anterior facial height increased in both treatment groups. Convexity angle (P = 0.020) and labiomental angle (P = 0.033) were greater in the Herbst group than the distalization group. Conclusions The skeletal contribution to correction of maxillomandibular discrepancy was greater in the Herbst group than the distalization group. Significant profile improvements were recorded for both groups with treatment. After both treatments, orthodontists were found to have higher rates of detection in the profiles than laypeople. The esthetic contribution of treatments to the facial profile was found similar in both groups.

To assess the fate and behavior of engineered nanoparticles in the aquatic environment, it is crucial to conduct appropriate bacterial bioassay procedure. However, test conditions of bacterial bioassay are limitedly investigated; especially in the field of environmental media chemistry or aging of nanoparticles which interfere the procedure. For this purpose, TiO2 nanoparticles were treated with different test conditions by keeping them in 1% and 100% seawater for one day and 20 days. The bacterial bioassay of treated nanoparticles towards gram-negative (Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria were examined, as well as the mechanism by biochemical responses of bacteria and physicochemical properties of TiO2 nanoparticles. The viability response of tested bacteria reduced remarkably in seawater concentration, while treatment (aging) duration of tested nanoparticles slightly affected the viability response of tested bacteria. Moreover, key events which affected the bioassay response were changed with the treatment duration and media concentration. The results also showed that aging duration and concentration of the media influenced the main physicochemical properties due to the alterations in surface from aging media compared to unaged ones.

In the environment, micro and sub-microplastics are involved in multiple processes; however, information regarding the effect of pathogen microorganisms, or aging on the behavior of microplastics, sub-microplastics and nanoplastics still needs examination. This study examined the degradation properties of sub-microplastics with one of the clinically important pathogens, Klebsiella pneumoniae. Various concentrations of sub-microplastics were aged with K. pneumoniae to improve understanding of the degradation process. Research results revealed that K. pneumoniae broke down the sub-microplastics; functional group indices showed that the most influenced functional groups in the surface were carbonyl, carbon–oxygen and vinyl groups; and the oxygen to carbon ratio were increased while the hydroxyl groups and crystallinity were not significantly affected. The breakdown was obtained in the lower particle sizes and with additive samples. Furthermore, biochemical response of K. pneumoniae was investigated and the optical density results indicated that the tested microorganism was activated with the sub-microplastics (2–43%), except the lowest concentration of S1 and S2 at 40 h aging, and their protein response played a more effective role in the activation than carbohydrate. The results also indicated that particle size, and breakdown particles influenced the activation level

Microplastics are persistent, synthetic polymers that have managed to spread even to the most remote places on earth. Studies reporting on the abundance of microplastics have recently increased worldwide, which has raised environmental concerns among scientific communities. Nevertheless, evidence of microplastic contamination from Turkey is limited even though the location is a critical point and the population is higher than most countries in the region. Thus, we aimed to detect microplastics in sediment samples collected from the Marmara Sea in Istanbul-Turkey. In this study, fourteen sediment samples were collected and sub-sampled, then plastic debris was extracted, quantified and characterized by the morphology and polymer structure. The result revealed that all of the samples contained microplastics, and their concentrations ranged between 0.3 and 85.6 g/kg sediment, and the most abundant plastic types were acrylonitrile butadiene styrene, ethylene vinyl acetate, and polystyrene.

In recent years, many studies have reported the harmful effects of plastic debris both on the environment and on human health. Therefore, the attempt has increased for the replacement of conventional plastics with bioplastics. On the other hand, not only the studies on the effects of bioplastics and conventional plastics in the field of micro-, submicron- and nano-sized are still very limited, but also knowledge of their relationship with clinically important bacteria. In this study, the effect of two end products made from bioplastics and their equivalent end products from conventional plastics were evaluated using clinically important gram-positive and gram-negative bacteria. To evaluate the effect of the submicron-sized bioplastics and conventional plastics on the bacteria, their viability and activation and/or inhibition mechanism were performed towards the main biochemical (protein, carbohydrate, lipid and antioxidant) and physicochemical (particle size, zeta potential, chemical composition, and surface chemistry) phenomenon. This work highlights the similarities and discrepancies between bio-based and conventional submicron-sized plastics in relation to bacteria.

Micron/submicron-sized plastic debris in the environment is a global issue of increasing concern and may harm human health. A large number of studies have shown that plastic debris has various toxicological effects on different organisms. Thus, efforts have increased to replace conventional plastics with bioplastics. However, investigations on the relation of submicron-sized bioplastics- and conventional plastics to culture-dependent biofilm formation and their similarities and discrepancies are still very limited. For this purpose, two end products made from bioplastics and their equivalent end products from conventional plastics were used to examine the response of the biofilm formation of selected clinically important bacteria. To evaluate the similarities and differences of submicron-sized bioplastics and conventional plastics on biofilm formation, the physicochemistry (particle size, zeta potential, chemical composition, and surface chemistry) of the tested plastics was examined, as well as the characteristics of the biofilms (categorization, protein/carbohydrate).

In this study, we reported the interaction between plastic traces and vital amino acids (L-homocysteine, L-valine, and L-lysine) in an aqueous system and characterized this interaction by Fourier transform infrared spectroscopy and Scanning electron microscopy with energy-dispersive X-ray spectroscopy studies. Bacterial activity and biofilm formation and their characteristics of non-treated and amino acid-treated plastic traces was tested against the

Over the last decade, it has become clear that the pollution by plastic debris presents global societal, environmental, and human health challenges. Increasing scientific attention on the occurrence and influence of plastic particles, and their potential toxic effects on the environment are evident. However, humans are also exposed to plastics in daily life and very limited information is available concerning human health, especially aging process in biological fluids and the colonization of the bacteria on plastics due to transport the pathogens, causing the infectious is another vital problem. Moreover, various studies also observed the importance of the nano-sized particles since a lower size can increase the activity, surface area etc. Therefore, the aim of this study is to investigate the in vitro (artificial saliva, artificial lysosomal fluid, phagolysosomal simulant fluid, Gamble’s solution) aging of plastic particles and the effect on the formation of Staphylococcus aureus biofilms with nanoplastics under in vitro conditions. We found that the surface properties of the nano-sized plastic particles changed according to the surrounding environment and surface deformation and the surface affinity to the biological activity was triggered with in vitro conditions due to higher hydroxyl index and carbon to nitrogen ratio. The results also showed that the Staphylococcus aureus biofilms formed with nanoplastics with the aging in vitro conditions. However, their levels and characteristic of extracellular polymeric substances were varied in these conditions with aging compared to control, and more basophilic extracellular polymeric substances were formed with these conditions.

In the present study, novel bioconjugated sorbents (peptide and oligo-nucleotide on the cobalt aluminate nanomaterials) were used to remove lead through miniaturised process and the concent...

Background: The enormous properties of metal oxide nanoparticles make it possible to use these nanoparticles in a wide range of products. As their usage and application continue to expand, environmental health concerns have been raised. In order to understand the behavior and effect of metal oxide nanoparticles in the environment, comprehensive and comparable physicochemical and toxicological data on the environmental matrix are required. However, the behavior and effect of nanoparticles in the real environmental matrix, e.g. sea water, are still unknown. Methods: In this study, the effects of zinc oxide (ZnO) and titanium dioxide (TiO2) nanoparticles on the bacteria (gram positive-Bacillus subtilis,Staphylococcus aureus/gram-negative Escherichia coli, and Pseudomonas aeruginosa) in sea water were investigated. Furthermore, to better understand the behavior of the toxicity, surface chemistry, sedimentation, dissolution, particle size, and zeta potential of the nanoparticles dispersed in the sea water matrices were investigated using Fourier-transform infrared spectrometry (FTIR), ultraviolet–visible (UV-VIS) spectrophotometry, graphite furnace atomic absorption spectrometer (GFAAS), and dynamic light scattering (DLS), respectively.Results: The environmental matrix had a significant influence on physicochemical behavior of the tested nanoparticles. Besides, the inhibition of tested bacteria was observed against ZnO and TiO2nanoparticles in the presence of sea water, while there was no inhibition in the controlled condition. Conclusion: The results demonstrate that surface chemistry with exposure to the sea water can have a significant role on the physicochemical properties of nanoparticles and their toxicity.

Over the last decade, pollution of plastics and antibiotics has increased in its threat to the environment and human health. However, very limited information is available concerning impact of co-presence of plastics and antibiotics on environment and human health. Moreover, the potential ingestion and inhalation of nano(micro)plastics due to the disposable materials has dramatically increased. With the outbreak and spread of the COVID-19 in the world, disposable surgical masks and plastic bottles have been widely used by the public, and their rapid use and improper dispensing can cause to increase plastic pollution risk on human. However, impacts of co-presence of nano(micro)plastics and antibiotics on pathogens have yet been demonstrated. Therefore, this study aims to investigate the impact the individual and combined influences of nano-sized plastics (surgical mask and plastic bottles) and antibiotics (amoxicillin and spiramycin) towards the main susceptible bacterium (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa) by microbial activity, biofilm formation and their biochemical characteristics. The results showed that antimicrobial efficiencies of the tested antibiotics were reduced (approximately 10-98%) with the plastics. Moreover, the biochemical pathways of the microbial activity changed by the plastics entrance. Polymer structure and sorption play the role on the reduction in the inhibition of pathogens. In the meantime, the biofilm formation changed and characteristic of the extracellular polymeric substance with the co-presence of plastics and antibiotics mostly depended on the polymer structure, exposure time and sorption.

In this study, we investigated the interaction of submicron-sized bioplastics with environmentally and clinically important bacteria under seawater and sediment conditions. To examine the relationship between submicron-sized bioplastics and bacteria in seawater and sediment, we focused on the bacterial activation and their biochemical key events toward the protein, carbohydrate, lipid, and antioxidant response. In addition, culture-dependent biofilm formation on submicron-sized bioplastics and their characterization was performed. The results indicated that selected bacteria increased their viability both in seawater and sediment with the submicron-sized bioplastics in that the bioplastics decreased their mass at the level of 10-23%. However, the activation level and mechanism affected the polymer type, bacteria, and environmental media, and submicron-sized bioplastics promoted biofilm formation with enhancing basophilic characteristics of biofilms.

Engineered nanomaterials (NMs) are being widely used in consumer and commercial products, leading to their inevitable increased release into the soil. In most cases, the results for the interactions of NMs with soil were inconclusive due to its complex nature. This complex nature of soil is composed of a matrix of minerals, organic matter, air, and water. To understand the fate and effects of engineered NMs, this study includes a detailed discussion of the current knowledge about the interaction of NMs with soil components. We classify and evaluate the nanomaterial studies according to their interactions with soil components to reveal the necessities and answer the unsolved problems in this field. The authors hope that, besides contributing to a better understanding of current overview of the effect of NMs on soil, this chapter will help to drive future investigations and will contribute to the general knowledge on the environmental interactions of engineered NMs.

Owing to the rapid growth of industrialization, urbanization, and modern agricultural practices, pollution of soil is on the rise. Heavy metal pollution of soil has been an environmental problem drawing worldwide attention over the decades. Various techniques can be utilized to clean up the contaminated soil from heavy metals for a healthy environment. With the advancement of nanotechnology, nanomaterials can function to sorb the contaminant, for example, metals and metalloids. Moreover, nanosized materials are capable of acting as sorbents to remove, remediate, and clean up heavy metals from soils using various technologies. This chapter gives brief explanations on the importance of metals in soil and their natural and anthropogenic sources in terms of soil. This chapter mainly reviews and evaluates the classification of natural and engineered nanomaterials, which are novel materials to remove, sorb, and clean up the metals in contaminated soil, using the available literature.

Introduction: The purpose of this research was to compare the effects of Herbst appliance therapy using incremental vs maximum advancement in late adolescent and young adult patients with Class II skeletal malocclusion. Methods: Forty-two patients with skeletal Class II malocclusion were treated with cast-splint Herbst appliances. The subjects were randomly allocated into 2 groups according to activation type: incremental advancement (IA) and maximum advancement (MA). Initial forward movement in the IA group was 4 to 5 mm and was followed by subsequent bimonthly advancements of 2 mm. Single-step advancement was achieved in the MA group until an edge-to-edge incisor relationship or an overcorrected Class I molar relationship was obtained. Total treatment times were 9.7 +/- 1.1 months for the IA group and 9.5 +/- 1.1 months for the MA group. Dental, skeletal, and soft tissue measurements were performed on lateral cephalograms taken just before and at the end of the Herbst appliance therapy. Statistical significance was set at P

The booming production and application of nanoparticles have raised great concern over its effect on environment, due to their increasing release in the environmental systems via intentional or unintentional activities, where their possible physicochemical and toxicological behavior remain unknown. The nanoparticles are released into the different environmental systems like air, soils and waters. However, their interaction with air matrices has been rarely investigated. For this reason, the changes of main physicochemical properties of Al2O3 nanoparticles in the presence of fine particulate matter were examined, as well as their toxicity towards gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) using colony counting method was assessed in the presence of fine particulate matter. E. coli and B. subtilis were the most strongly affected species by the Al2O3 nanoparticles under the influence of fine particulate media. Furthermore, the main physicochemical properties (particle size, zeta potential, and surface chemistry) were changed with the exposure of the fine particulate matter. Sulfone groups were detached and nitro groups were attached on nanoparticles surface according to FTIR analysis. Particle size of Al2O3 was decreased with the correlation of zeta potentials. This is one of the rare study to evaluate the effect of fine particulate media on Al2O3 nanoparticles with the respect of the physicochemical properties and toxicity of Al2O3.

Soils are facing new environmental contaminants, such as nanomaterials. While these emerging contaminants are increasingly being released into soil, their potential impact on this medium and their effect on soil's major chemical components (e.g., sulfate, nitrate, ammonia, and phosphate) have yet to be examined, as well as their relation with microbial toxicity. Herein, column experiments were conducted to investigate the behavior of major ions under 10 and 200 mg/L multiple contaminations of graphene nanomaterials in agricultural and undisturbed soils, as well as the retention of the graphene nanomaterials in the soil and their effect on soil zeta potentials throughout the column. Moreover, to evaluate the impact of the risks of graphene nanomaterial contamination on soil major ions, the present study also examines the bacterial toxicity. The results showed that graphene retention was influenced the soil zeta potentials. Graphene also influenced the concentrations of the major ions in soil and the order of the influence degree was sulfate > phosphate > ammonia > nitrate. The changes of the major ions in soil by the exposure of graphene nanomaterials have also affected the response of selected bacteria.

The behavior of nanoparticles released to the soil has been extensively studied in recent years; however, the effects of nanoparticles on the distribution of soil elements and on sowing are still unknown. To this end, to examine the distribution of selected elements in soil, soil samples were treated weekly with 1.0 mg and 20.0 mg of Al2O3 nanoparticles for 3 weeks. Additionally, different types of plants (including taproot, fibrous root and ornamental bulbous plants) were sowed in the soil samples. After each treatment, surface soil samples were collected and digested with acid digestion. The concentrations of selected elements (Ca, Mg, Fe, Al, Cu, Co, Ni) were determined using a microwave plasma atomic emission spectrometer. Al2O3 treatment for 3 weeks, both low and high doses, had no effect on the Al content in soil samples when compared to the controls. Additionally, Al2O3 showed desorption properties on the analyte elements.

In the last few decades, metal oxide nanoparticles have shown impact in various areas, and such an impact causes an increased release in a different environment like soil, water, or air. A limited ...

In order to separate and enrich of cadmium, copper, lead and nickel before its determination with graphene nanoplatelets by atomic absorption spectrometry was described. For this aim, analyte eleme...

In this study, a challenging nanosorbent was described for preconcentration/separation method based on the sorption of cadmium, cobalt, copper, nickel, lead on starch coated titanium dioxide nanoparticles and its analysis by graphite furnace atomic absorption spectrometry. Optimum conditions were investigated for quantitative sorption. By using the proposed technique, the analyte elements were determined in spiked tap-water samples in the range of 95% confidence level. Limit of detection (3δ) was 0.05, 0.28, 1.90, 3.10 and 0.11 µg/L (3σ, N = 10) for cadmium, cobalt, copper, nickel and lead, respectively. The optimised technique is fast, easy handled, simple and environmental friendly.

Human hair is a valuable contributor for biological monitoring. It is an information storage point to assess the effects of environmental, nutritional or occupational sources on the body. Human proteins, amino acids or other compounds are among the key components to find the sources of different effects or disorders in the human body. Sulfur is a significant one of these compounds, and it has great affinity to some metals and compounds. This property of the sulfur affects the human health positively or negatively. In this manuscript, sulfur was determined in hair samples of autistic and age-match control group children via molecular absorption of CS using a high-resolution continuum source graphite furnace atomic absorption spectrometer. For this purpose, hair samples were appropriately washed and dried at 75 °C. Then samples were dissolved in microwave digestion using HNO 3 for sulfur determination. Extraction was performed with HCl hydrolysation by incubation for 24 h at 110 °C for total protein and albumin determination. The validity of the method for the sulfur determination was tested using hair standard reference materials. The results were in the uncertainty limits of the certified values at 95% confidence level. Finally correlation of sulfur levels of autistic children's hair with their total protein and albumin levels were done.

Sulfur is one of the most abundant elements on the crust of Earth, and it is an essential element for animals and plants. In addition to playing a vital role in living organisms, it has a very important use in industry as an ingredient in some chemicals, fertilizers, fungicides, pesticides, pharmaceuticals, and so on. There are limit values for sulfur content in many matrices, which explains why it is important to determine sulfur contents. This review aims to give an overview of historical development and importance of sulfur determination by high-resolution continuum source atomic absorption spectrometry (HR CS AAS). We primarily focus on recent applications and their optimized parameters for the determination of sulfur in many matrices. The application of sulfur determination by HR CS AAS is evaluated and some scientific properties of sulfur determination by HR CS AAS are also presented.

Assessing the environmental hazard of nanoparticles can be a challenging task using various testing strategies. However, to our knowledge, no information is available about the impact of the sample preparation on the toxicity and toxicity mechanism of nanoparticles. For this aim, three sample preparation methods and their available toxicity procedures were conducted to examine the (eco) toxicity of TiO2 nanoparticles using bacteria model system. To detail understanding of the effect of sample preparation, the key events on the inhibition were examined by physicochemical and antioxidant responses. The findings showed that the physicochemical and toxicological behavior of the tested TiO2 NPs varied according to the sample preparation method.

Nanoparticles are increasingly used in various products, and their unavoidable release into the environment is a becoming major concern. In order to understand their effects in environment components (air, soil, water), important stages are detection of nanoparticles in environment and their toxicity. The current chapter is provided a detailed overview of the background information of nanoparticles, their detection methodology and interaction with air. In the section of detection of nanoparticles, we are focusing on the sample in matrix, sample preparation methods and detection techniques. Available analytical sample preparation and detection techniques as well as emerging techniques such as electroanalytical and sensors based, are also presented. This section also includes overview potential gaps and advantages in the analytical methodology. This chapter also evaluates the toxicity of these nanoparticles in environment with focusing interaction in air. For this purpose, their release, transformation and toxicity approaches were examined with available literature examples.

Microplastics have become a global concern due to their increasing use and discharge into the environment. These ubiquitous particles are known to have extremely low degradation rates and accumulate mostly in the marine environment. The evidence for bioaccumulation and indicators of stress linked to microplastics is also stated in the literature. However, the real environmental impact of microplastics has not yet been revealed. Therefore, it is crucial to understand the interaction mechanisms between microplastics and (micro)organisms under controlled (standard) laboratory conditions and environmentally relevant conditions to reflect the true environmental -situation. In this study, we aimed to understand how microplastics extracted from commercially available toothpaste samples interacted with four types of bacteria under both standard and seawater conditions. For this purpose, bacterial inhibitions were examined, and mechanisms of inhibition were evaluated by biochemical parameters (total protein, lipid peroxidase, total antioxidant capacity, and extracellular carbohydrate levels) of bacteria and physicochemical properties (zeta potential, particle size, surface chemistry) of microplastics. Results showed that gram-positive Bacillus subtilis and gram-negative Pseudomonas aeruginosa were affected in controlled and sea water media, respectively. The inhibition of the bacteria relied on the high zeta potentials of the microplastics, and, biochemically, protein and lipid peroxidase activity of bacteria were important in both media. On the other hand, while biochemical responses were similar in both media, the difference between the cell wall and microplastics surface charge was important only in seawater.

Objective This study aimed to assess intra-examiner and inter-examiner reproducibility in irregularity index measurements. Methods Twenty plaster casts of moderately crowded arches were randomly selected, and five contact point displacements (CPD) at lower anterior segment (through no. 33 to no. 43) were recorded using digital calipers on two different time points by three examiners to determine irregularity index (sum of five CPDs). To evaluate intra-examiner and inter-examiner differences, paired t-test and analysis of variance were used, respectively. Correlation analyses were performed between examiner pairs, and intra-class correlation coefficients (ICC) were determined. Statistical significance was set at p≤0.05. Results Only a few of the repeated measurements of examiners showed significant differences (p≤0.05). All researchers were consistent in repeated measurements (p=0.000), and ICCs ranged between 0.916 and 0.986. For one CPD measurement, a statistically significant difference was detected among examiners (p=0.020). High correlation was found for inter-examiner repeatability (p

Assessing the environmental hazard of nanoparticles can be a challenging task using various testing strategies. However, to our knowledge, no information is available about the impact of the sample preparation on the toxicity and toxicity mechanism of nanoparticles. For this aim, three sample preparation methods and their available toxicity procedures were conducted to examine the (eco) toxicity of TiO

Microplastics have become a major environmental issue; their release from various products affects the aquatic environment. Personal care products such as toothpastes are recently being considered as a significant source of microplastics released to the aquatic environment. This study aims to assess the presence of microplastics found in toothpastes that are available in the drugstores and markets in Istanbul, Turkey. A total of 20 samples were tested. Following the extraction procedure, obtained particles were quantified and then characterized by microscopic evaluation and surface chemistry analysis. Twenty percent of the samples were found to contain microplastics in the structure of polyethylene at concentrations varying between 0.4 and 1%. In order to evaluate the release to environment, a risk assessment was conducted and yearly microplastic emission caused by toothpaste consumption was calculated based on the results.

OBJECTIVES This was a parallel, assessor-blinded, randomized, non-controlled prospective trial with the objective to evaluate and compare the effects of maximum advancement (MA) and incremental advancement (IA) of mandible with cast-splint-type Herbst-rapid palatal expander (RPE) appliance on pharyngeal airway dimensions and hyoid bone position in skeletal Class II late adolescents and young adults. MATERIALS AND METHODS A total of 48 patients (19 male and 29 female, mean age: 15.45 ± 1.42 years) with skeletal Class II malocclusion were treated with cast-splint Herbst-RPE appliance. Inclusion criteria were skeletal Class II malocclusion, mandibular retrognathia, bilateral Class II molar and canine relationship, increased overjet, normal or decreased vertical dimensions, minimal crowding, and no missing teeth. Enrolled subjects were randomly allocated into two groups according to mandibular advancement type: IA and MA Herbst-RPE therapy. The outcome assessor was blinded. Advancement in MA group was adjusted until tete-a-tete incisor relationship or super Class I molar relationship was obtained. Initial forward movement in IA group was 4-5 mm and followed by bimonthly 2 mm of subsequent advancements. Skeletal, pharyngeal airway, and hyoid measurements were performed using lateral cephalometric films. Statistical significance was set at P value of less than 0.05. RESULTS Hypopharyngeal airway dimensions (P < 0.000), oropharyngeal airway dimensions (P < 0.001, P < 0.007), and PASmin values (P < 0.010, P < 0.009) were increased and soft palate angle (P < 0.018, P < 0.007) was decreased in MA and IA groups significantly. Hyoid bone measurements revealed a significant difference in H-Cv2 distance (MA: P < 0.002-P < 0.002; IA: P < 0.001-P < 0.043) and H-Cv3 distance (P < 0.005, P < 0.001) for both groups. However, all these changes did not differ among the MA and IA activation groups. ANB°, Wits, overjet, and overbite measurements decreased and SNB°, Co-Gn, Na-Me, ANS-Me, and S-Go increased with the treatment significantly in both mandibular advancement groups (P < 0.000-P < 0.040). CONCLUSIONS Herbst-RPE appliance provided a similar improvement in the oropharyngeal and hypopharyngeal airway dimensions and similar changes in sagittal and vertical hyoid position for both maximum and IA protocols in patients with skeletal Class II malocclusion. TRIAL REGISTRATION ISRCTN69743543.

In this work, water and nitric acid extractable sulphur concentrations in PM2.5 fraction of urban aerosols were determined by high-resolution continuum source electrothermal molecular absorption spectrometry using most suitable CS molecular absorption band at 258.056 nm. For this purpose, the PM2.5 airborne particulates were collected on quartz filters using a high-volume sampler (500 L/min) in Istanbul (Turkey) during six months (January–June) of two consecutive years. The instrumental and experimental parameters (pyrolysis temperature, molecule formation temperature and leaching reagents) were optimised. The validity of the method for the sulphur was tested using standard reference material and the results were found to be in the uncertainty limits of the certified value.

Objective: To evaluate the intraexaminer repeatability and interexaminer reproducibility of soft tissue landmarks on three-dimensional (3-D) stereophogrammetric images. Materials and Methods: Thirty-four stereophotogrammetric images were taken and 19 soft tissue points were identified. The images were obtained using the 3-DMD Face (3-DMD TM Ltd, Atlanta, Ga) system. Two examiners marked 34 images manually with a mouse-driven cursor 4 weeks apart. Intraexaminer marking differences were calculated and classified as 1 mm. Intraclass correlation coefficients were calculated for intraexaminer reliability. A paired-samples t-test was used to evaluate the difference between the examiners. Interexaminer reproducibility was evaluated by kappa analysis. Statistical significance was set at P < .05. Results: Only one landmark (labiale superior) had an intraexaminer marking difference less than 0.5 mm. Existing landmarks had an intraexaminer difference less than 1 mm, but higher than 0.5 mm. The intraclass correlation coefficients (ICCs) indicated good intraexaminer repeatability for both observers. The ICC range for examiners 1 and 2 was 0.986–1.000 and 0.990–1.000, respectively. Kappa scores showed good interexaminer agreement, especially on the z-axis. Conclusions: Except labiale superior, the soft tissue landmarks used in this study were shown to have moderate reproducibility, but the difference between the landmarks was less than 1 mm, and they had clinically acceptable reproducibility.

Fluorine determination in airborne samples is important due to its spread into the air from both natural and artificial sources. It can travel by wind over large distances before depositing on the Earth's surface. Its concentration in various matrices are limited and controlled by the regulations for causing health risks associated with environmental exposures. In this work, fluorine was determined in PM2.5 airborne samples by high-resolution continuum source electrothermal atomic absorption spectrometry. For these purpose, the PM2.5 airborne particulates were collected on quartz filters using high-volume samplers (500 L/min) in Istanbul (Turkey) for 96 h during January to June in 2 years. Then, instrumental and experimental parameters were optimized for the analyte in airborne samples. The validity of the method for the analyte was tested using standard reference material, and certified values were found in the limits of 95 % confidence level. The fluorine concentrations and meteorological conditions were compared statistically.