Effects of contemporary orthodontic composites on tooth color following short-term fixed orthodontic treatment: A controlled clinical study

Background/aim: To determine the color alterations of natural teeth associated with different orthodontic composites used in comprehensive short-term treatment. Materials and methods: Twenty-two patients were treated with fixed appliances and 22 untreated subjects were also evaluated. Lower incisors were bonded with different orthodontic composites: 42 with Grengloo, 41 with Light Bond, 31 with Kurasper F, and 32 with Transbond XT. The color parameters of the Commission Internationale de l’Eclairage (CIE) were measured for each tooth with a spectrophotometer. Color assessment in relation to time, adhesive material, and their interaction was made with 2-way mixed analysis of variance (ANOVA) and 1-way ANOVA for the color differences (ΔE*). Further analyses were done using Tukey’s honestly significant difference tests and paired-samples t-tests. Results: The color of teeth was affected by treatment. The mean L* and a* values increased, whereas the mean b* values decreased. Total color differences of teeth demonstrated visible color changes clinically after treatment, ranging from 1.12 to 3.34 ΔE units. However, there were no significant differences for color of enamel. Conclusion: Teeth may be discolored with fixed appliances during treatment. Moreover, contemporary orthodontic composites have similar effects of enamel discoloration. © TÜBİTAK

Communications of the median nerve in foetuses

Background: Communications between the median, ulnar and musculocutaneous nerves in the arm, forearm and hand were reported in adult cadaveric and electrophysiological studies. These communicant branches may lead conflicting clinical and electrodiagnostic outcomes. While there are many studies on adult patients or cadavers, there is poor regarding foetuses. The present study was conducted to examine the frequencies of these communications and their coexistences in human foetuses.Materials and methods: Anterior aspect of the forearms of 50 foetuses (29 females, 20 males, and 1 unknown) were dissected bilaterally (totally 100 sides) for this purpose.Results: Communications between the median and the musculocutaneous nerves in the arm were found unilaterally in 4%. Communications from the median to the ulnar nerve in the forearm were encountered unilaterally in 22%, and bilaterally in 12%; from the ulnar to the median nerve in the hand unilaterally in 28%, and bilaterally in 12%. Coexistence of all these variations was not encountered in any foetus. But coexistence of two different types of communicant branch was encountered in 4%.Conclusions: Precise knowledge of nerve communications, variations and rate of coexistences in foetuses may have significance for clinicians and researchers dealing with subjects in foetal period

Soft Bottom Molluscan Assemblages of the Bathyal Zone of the Sea of Marmara

The present study deals with the soft bottom molluscan species collected from the bathyal zone of the Sea of Marmara in 2013. Replicated samples were taken by a Box Core, sampling an area of 0.1 m2 at 31 stations at the two depth transects, 500 and 1000 m. A total of 1229 individuals belonging to 4 classes and 28 species were collected. Two species (Akritogyra conspicua and Liostomia hansgei) are new records for the marine molluscan fauna of Turkey and four species (Benthonella tenella, Odostomia silesui, Syrnola minuta and Crenilabium exile) are new records for the molluscan fauna of the Sea of Marmara. A relatively richer fauna was determined in 500 m (25 species) than in 1000 m (17 species). The most dominant species at 500 m and 1000 m depths were Crenilabium exile and Parthenina flexuosa, respectively. Number of species and number of individuals varied significantly only between depths while number of individuals changed significantly among basins (ANOVA test). A significant difference in species assemblages between the Tekirdağ and the Central Basins was detected (ANOSIM test). The multivariate analysis showed that the depth was the main factor influencing the molluscan assemblages in the area

Preparation of poly(glycerol sebacate) fibers for tissue engineering applications

Poly(glycerol sebacate) (PGS) was discovered in the previous decade and is a promising bioelastomer with tuneable mechanical, biodegradable and biocompatible properties. Despite of these superiorities, PGS possesses solubility and processability disadvantages. To overcome these drawbacks of PGS, blends could be formed with a polymer which is soluble in a common solvent with PGS prepolymer, having a melting temperature above the crosslinking temperature and which can be removed from the structure after crosslinking. In this study, PGS fibers were fabricated for the first time using pressurized gyration as scaffolds. Fibers were obtained through blending the synthesized PGS prepolymer with poly(vinyl alcohol) (PVA) to overcome solubility/melting drawbacks of crosslinked PGS polymer. Obtained fiber diameters have a narrow size distribution which did not change after thermal crosslinking. After the washing procedure, ∼25% decrease in the average fiber diameter was observed due to the PVA removal. Resulting PGS fibers were characterized in terms of chemical structure, morphology, and cell viability. Fibroblast cell adhesion and spreading on three-dimensional fiber networks were determined by microscopy. PGS fibers supported cell adhesion and proliferation. After 7 days of cell-PGS fiber interactions, cell proliferation and spreading increased without any toxicity

Applicability of Fenton and photo-Fenton Processes to Combined Industrial and Domestic Wastewater

The applicability of Fenton and photo-Fenton processes as a pretreatment stage to combined wastewater was investigated. The wastewater was obtained from the inlet of the aeration tank in 42 Evler industrial and domestic wastewater treatment plant. The effects of different process variables such as initial Fe2+ (c0 = 8-33 mmol L–1) and H2O2 (c0 = 65-165 mmol L–1) concentrations, pH (3-7.75) and reaction time (t = 5-180 min) were evaluated. The Fenton process was investigated which under the operating conditions (pH 3, cFe2+ = 12 mmol L–1, cH2O2 = 130 mmol L–1) 100 % color and 44 % total organic carbon (TOC) removal were achieved. However, 71 % TOC removal was achieved at pH 7.75 by coagulation but color was poorly removed (c = 20 mmol L–1 Fe2+, c = 165 mmol L–1 H2O2). In the photo-Fenton process, 84 % TOC and 87 % color removal were achieved in 30 min reaction time (pH 3, cFe2+ = 26 mmol L–1, cH2O2 = 130 mmol L–1)

Greater Expectations?

Physically Unclonable Functions (PUFs) are key tools in the construction of lightweight authentication and key exchange protocols. So far, all existing PUF-based authentication protocols follow the same paradigm: A resource-constrained prover, holding a PUF, wants to authenticate to a resource-rich verifier, who has access to a database of pre-measured PUF challenge-response pairs (CRPs). In this paper we consider application scenarios where all previous PUF-based authentication schemes fail to work: The verifier is resource-constrained (and holds a PUF), while the prover is resource-rich (and holds a CRP-database). We construct the first and efficient PUF-based authentication protocol for this setting, which we call converse PUF-based authentication. We provide an extensive security analysis against passive adversaries, show that a minor modification also allows for authenticated key exchange and propose a concrete instantiation using controlled Arbiter PUFs

Multidetector computed tomography findings of an asymptomatic levoatrial cardinal vein with an interatrial course

A 57-year-old female patient with a family history of coronary artery diseaseadmitted to our hospital for the coronary check-up. A coronary angiographywas performed with ECG-gated 128 slice dual source computed tomography.Multidetector computed tomography (MDCT) showed, in addition to the normalcoronary arteries, a persistent levoatrial cardinal vein (LCV) draining into vena cavasuperior. ECG-gated cardiac MDCT is a useful tool showing the origin, course, anddrainage site of LCV