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Introduction/Aim. Avulsions are severe dental injuries with high impact on patients' quality of life due to prolonged treatment and possible severe complications. The aim of the study was to analyze the epidemiological factors related to the occurrence, treatment and outcome of avulsions in Serbian children. Methods. This research included 2,194 patients aged 1-18 years with traumatic dental injuries. The history, demographic, clinical and radiographic data of the patients were observed from dental medical records. Results. A total of 266 avulsions were observed in 207 patients. The frequency of avulsions was 12% in primary dentition and 5% in permanent dentition. A statistically significant relationship between place, cause of avulsion and outcome was observed. Replantation of permanent teeth was performed in 46.7% with a mean time 6.9 h. Almost a half of permanently avulsed teeth (48.7%) were not retrieved from the accident site and 11.3% of replanted teeth were transported in adequate media. The observed incidence of complications was 31.9%. Conclusions. Replantation was not performed in more than a half of all eligible teeth due to either loss or inadequate/delayed transport, which emphasizes the need for preventive strategies and health education in population. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A synthesis of a new dental material, based on nano-structured highly active calcium silicates and calcium carbonates, is described in this paper. Phase analysis of this material, before and after hydration, was performed by X-ray diffraction and showed that active silicate phases were transformed into tobermorite phase, while carbonates remained unchanged. The mechanism of hydration was fully described. The morphology of the sample was studied by SEM, and typical appearance of the present phases was particularly discussed. The mechanical properties and setting time of this material make it very promising for potential application in dental practice. [ABSTRACT FROM AUTHOR]

Copyright of Serbian Dental Journal / Stomatološki Glasnik Srbije is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this work was to estimate the degradation and change in the antioxidant activity of quercetin in the presence of two different mixtures of phospholipids in methanolic solution, under continuous UV-irradiation from three different sub-ranges (UV-A, UV-B and UV-C), in the presence and in the absence of the selected UV-absorbing photosensitizer, benzophenone. Quercetin was employed to control the lipid peroxidation process generated by UV-irradiation, by absorbing part of the UV incident light, and/or by scavenging the involved, created free radicals. The results showed that quercetin undergoes irreversible destruction, which was highly dependent on the energy input of the UV-photons, and was more expressed in the presence than in the absence of benzophenone. Simultaneously, quercetin expressed a suppression effect on lipid peroxidation processes in UV-irradiated phospholipid mixtures in both the absence and presence of benzophenone (more or less effective, respectively). In the UV-C-irradiated mixtures, photosensitizing function of benzophenone was significantly reduced due to its strong absorption in the UV-C spectral range, therefore affecting lower antioxidant activity of the remaining quercetin. [ABSTRACT FROM AUTHOR]

Lycopene antioxidant activity in the presence of two different mixtures of phospholipids in hexane solution, under continuous regime of UV-irradiation from three different ranges (UV-A, UV-B, and UV-C) has been evaluated in this work. Lycopene expected role was to control lipid peroxidation, by scavenging free radicals generated by UV-irradiation, in the presence and in the absence of selected photosensitizer, benzophenone. This work shows that lycopene undergoes to UV-induced destruction (bleaching), highly dependent on the incident photons energy input, more expressed in the presence than in the absence of benzophenone. The further increase ('excess') of its bleaching is undoubtedly related to the further increase of its antioxidant activity in the presence of benzophenone, having the same cause: increase of (phospholipids peroxidation) chain-breaking activities. [ABSTRACT FROM AUTHOR]

Background/Aim. Retention of fissure sealants and good adaptation to enamel are essential for their success. Fluoride releasing resin-based materials are widely accepted for pit and fissure sealing, but newly designed glass ionomers can serve as a good alternative. The aim of this study was to evaluate microleakage and sealing ability in vitro, and to clinically assess two fluoride releasing fissure sealants. Methods. The sample for experimental study consisted of 20 freshly extracted intact human third molars, divided in two experimental groups according to the sealing material: fluoride releasing resin-based (Heliosel F) and glass ionomer (Fuji Triage) material. Digital images and scanning electron microscope were used to assess microleakage and adaptation ability. Sample for clinical study consisted of 60 children, aged 6-8 years, with high caries risk, divided in two groups according to the sealant material. Fissure sealant was applied to all erupted, caries-free first permanent molars. Sealants were evaluated after 3, 6 and 12 months using modified Ryge criteria for retention, marginal adaptation, colour match, surface smoothness and caries. Results. Microleakage was detected in more than half of the specimen, without significant differences between the two groups (p > 0.05). Both materials exhibited acceptable sealing ability. Complete retention at the end of the observation period was 81.8% for resin-based, and 21.1% for glass-ionomer fissure sealant (p < 0.001). The presence of caries in sealed molars has been detected in one patient in both groups. During the 12-month observation period, Helioseal F demonstrated better retention, marginal adaptation and surface smoothness (p < 0.001). There were no differences between the two materials regarding caries and color match (p > 0.05). Conclusion. Both tested materials demonstrate satisfactory clinical and caries prophylactic characteristics that justify their use in contemporary preventive dentistry [ABSTRACT FROM AUTHOR]

The stability of Zn(II) and Cu(II) complexes of porphyrin derivatives (pheophytin and mesoporphyrin) to UV-B irradiation was studied by absorbance spectroscopy in 95 % ethanol. The chosen porphyrins and their heavy metal complexes underwent first-order photochemical decomposition. In general, pheophytin was more stable than mesoporphyrin to UV-B irradiation. Moreover, the stabilities of the Zn(II) complexes were lower than those of the Cu(II)-complexes for both pheophytin and mesoporphyrin. However, while the Cu(II)-complex with pheophytin was more stable than the one with mesoporphyrin, the situation was vice versa for the Zn(II)-complexes. [ABSTRACT FROM AUTHOR]

Copyright of Serbian Dental Journal / Stomatološki Glasnik Srbije is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The stabilities and antioxidant action of two selected flavonoids, quercetin and rutin, dissolved in methanol and water, toward continuous UV-irradiation from three different sub-ranges (UV-A, UV-B and UV-C) were studied. The flavonoids underwent degradation (bleaching) following first-order kinetics. The bleaching rates were highly dependent on the energy input of the involved UV-photons. The antioxidant activities of the two flavonoids on UV-induced lecithin lipid peroxidation were studied by the thiobarbituric acid-malondialdehyde (TBA-MDA) test, and appeared to be also affected by the continuous UV irradiation. The energy input of the incident UV-photons again played a major governing role, but an impact of the flavonoids structures cannot be neglected. [ABSTRACT FROM AUTHOR]

Copyright of Serbian Dental Journal / Stomatološki Glasnik Srbije is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Chirurgica Iugoslavica is the property of Association of Yugoslav Surgeons and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an automated tool for floating-point to fixed-point conversion. The tool is based on previous work that was built in MATLAB/Simulink environment and Xilinx System Generator support. The tool is now extended to include Synplify DSP blocksets in a seamless way from the users' view point. In addition to FPGA area estimation, the tool now also includes ASIC area estimation for end-users who choose the ASIC flow. The tool minimizes hardware cost subject to mean-squared quantization error (MSE) constraints. To obtain more accurate ASIC area estimations with synthesized results, 3 performance levels are available to choose from, suitable for high-performance, typical, or low-power applications. The use of the tool is first illustrated on an FIR filter to achieve over 50% area savings for MSE specification of 10~6 as compared to all 16-bit realization. More complex optimization results for chip-level designs are also demonstrated. [ABSTRACT FROM AUTHOR]

The use of spin-transfer torque (STT) devices for memory design has been a subject of research since the discovery of the STT on MgO-based magnetic tunnel junctions (MTJs). Recently, MTJ-based computing architectures such as logic-in-memory have been proposed and claim superior energy-delay performance over static CMOS. In this paper, we conduct exhaustive energy-performance analysis of an STT-MTJ-based logic-in-memory (LIM-MTJ) 1-bit full adder and compare it with its corresponding CMOS counterpart. Our results show that the LIM-MTJ circuit has no advantage in energy-performance over its equivalent CMOS designs. We also show that the MTJ-based logic circuit requiring frequent MTJ switching during the operation is hardly power efficient. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to examine factors associated with avulsion injury and to specify the association between these factors and the treatment, as well as the outcomes of avulsed permanent incisors in children. Materials and methods: The sample consisted of 51 children with 62 avulsed permanent incisors, whose injuries had been managed in the period 1998–2006. The study was prospective, recording the history of the accident, concomitant injuries, age, gender, apical maturity of the root, replantation rate, storage media, extra-alveolar duration, endodontic treatment, compliance and recall appointments response. Factors were analysed in relation to postoperative outcomes, classified as functional healing (FH), infection-related (inflammatory) resorption (IRR) and replacement resorption ( RR). Results: The average age of patients was 10.7 years (range 7–19). In 16/51 patients, tooth avulsion was caused by a road traffic accident. Avulsion was accompanied by concomitant injuries in all cases. Thirty of 62 avulsed teeth were not replanted and 32 incisors were replanted after dry storage. Time until replantation ranged between 15 min and 9 h (median 60 min). The observation period ranged from 1 to 6 years (median 2 years). FH was observed in 5/32, IRR in 20/32 and RR in 7/32 incisors. Ten teeth were extracted during 5-years of observation. Immature incisors exhibited significantly more complications compared with mature teeth ( P = 0.04). Storage media and extra-alveolar duration did not significantly affect the survival of replanted teeth ( P = 0.253, P = 0.350). Teeth in which endodontic treatment was in temporary phase exhibited significantly more complications in comparison with teeth with completed endodontic treatment ( P = 0.0l6). Conclusion: The combination of delayed replantation and unphysiological storage is followed by low survival. Incisors with open apices exhibited lower survival compared with incisors with closed apices. Replanted incisors that required prolonged treatment with calcium hydroxide exhibited more complications compared with incisors with completed root canal treatment. [ABSTRACT FROM AUTHOR]

Operation in the subthreshold region most often is synonymous to minimum-energy operation. Yet, the penalty in performance is huge. In this paper, we explore how design in the moderate inversion region helps to recover some of that lost performance, while staying quite close to the minimum-energy point. An energy-delay modeling framework that extends over the weak, moderate, and strong inversion regions is developed. The impact of activity and design parameters such as supply voltage and transistor sizing on the energy and performance in this operational region is derived. The quantitative benefits of operating in near-threshold region are established using some simple examples. The paper shows that a 20% increase in energy from the minimum-energy point gives back ten times in performance. Based on these observations, a pass-transistor based logic family that excels in this operational region is introduced. The logic family operates most of its logic in the above-threshold mode (using low-threshold transistors), yet containing leakage to only those in subthreshold. Operation below minimum-energy point of CMOS is demonstrated. In leakage-dominated ultralow-power designs, time-multiplexing will be shown to yield not only area, but also energy reduction due to lower leakage. Finally, the paper demonstrates the use of ultralow-power design techniques in chip synthesis. [ABSTRACT FROM AUTHOR]

A method for modeling the effects of random process variation through measured transistor current is introduced. The methodology culminates by modeling random current variation at a given operating point above threshold as a zero-mean Additive White Gaussian Noise (AWGN) current source with a standard deviation dependent on nominal operating current and design variables, the transistor sizes, W and L, and the transistor operating points, Vgs and Vds. The model has a simple posynomial form and is accurate compared to measured data within an RMS error of 5.4% for narrow-, wide-, short-, and long-channel transistors. The model's simplified form bridges the gap between existing statistical methods and circuit design. The efficacy of the model in the circuit design space will also be presented. In the analog domain, we will show that the contributions of this model can be used as a re- placement for Monte Carlo methods for calculating circuit voltage and current variances. In the digital space, we will investigate the calculation of timing delay distributions. Results calculated via an alpha-power (αp) law model for average current show that scaling the supply voltage by γ results in an approximately 1 /γ⪢p+ 1.1 scaling in the path-delay standard deviation for a 65-nm process. [ABSTRACT FROM AUTHOR]

The effects of ultraviolet radiation (UV) on the antioxidant action of three selected carotenoids (β-carotene, lycopene and lutein) in the presence of a lipoidal lecithin mixture were studied by the DPPH (1,1-diphenyl-2-picrylhydrazyl) test. The test is based on the measurement of the decrease of the free DPPH radical absorbance at 517 nm caused by the antioxidant action of carotenoids, which appeared to be strongly affected by UV-action. The high-energy input of the involved UV-photons plays a major governing role. [ABSTRACT FROM AUTHOR]

The stability of chlorophylls toward UV irradiation was studied by Vis spectrophotometry in extracts containing mixtures of photosynthetic pigments in acetone and n-hexane. The chlorophylls underwent destruction (bleaching) obeying first-order kinetics. The bleaching was governed by three major factors: the energy input of the UV photons, the concentration of the chlorophylls and the polarity of the solvent, implying different molecular organizations of the chlorophylls in the two solvents. [ABSTRACT FROM AUTHOR]

The stabilities of four selected carotenoids dissolved in hexane, two carotenes and two xanthophylls, toward UV-irradiation of three different ranges (UV-A, UV-B and UV-C) were studied in this work. The carotenoids underwent bleaching via a probable free radical mediated mechanism following first-order kinetics. The bleaching rates were highly dependent on the input of the involved photons and, although not consistently, on the chemical structures of the investigated compounds. For the two xanthophylls, a possible role of oxygen associated with their bleaching cannot be neglected. [ABSTRACT FROM AUTHOR]

The possibility of the formation of copper and zinc complexes with chlorophyll in photosynthetic organelles (chloroplasts) and suborganelles (thylakoids) was studied. The visible and fluorescence spectra obtained from chloroplasts and thylakoids in the presence of the two metals confirmed complex formation in the case of copper, while such possibility appears to be very minor in the case of zinc. The reason for this distinction lies in the different type of complexes which chlorophyll forms with the two metals: only "central" or "substitution" copper-chlorophyll complexes may be formed inside the two isolated entities, while the formation of a possible zinc-chlorophyll "peripheral" type of complex is prevented for steric reasons. The latter fact is of high biological relevance, since both complexes may cause an irreversible impairment and damage of photosynthetic function. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the anticipated antioxidant role of four selected carotenoids in mixtures with lecithin lipoidal compounds in hexane solution, under continuous UV-irradiation in three different ranges (UV-A, UV-B and UV-C). Two carotenes (β-carotene and licopene) and two xantophylls (lutein and neoxanthin) were cmployed to control the lipid peroxidation process generated by UV-irradiation, by scavenging the involved free radicals. The results show that while carotenoids undergo a substantial, structural dependent destruction (bleaching), which is highly dependent on energy of the UV-photons, their contribution to the expected suppression of lecithin peroxidation is of marginal importance, not exceeding a maximum of 20%. The marginal antioxidant behaviour has been attributed to a highly unordered hexane solution, where the scavenging action of the carotenoids becomes less competitive. [ABSTRACT FROM AUTHOR]

Copyright of Serbian Dental Journal / Stomatološki Glasnik Srbije is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents methods for efficient energy-performance optimization at the circuit and micro-architectural levels. The optimal balance between energy and performance is achieved when the sensitivity of energy to a change in performance is equal for all the design variables. The sensitivity-based optimizations minimize energy subject to a delay constraint. Energy savings of about 65% can be achieved without delay penalty with equalization of sensitivities to sizing, supply, and threshold voltage in a 64-bit adder, compared to the reference design sized for minimum delay. Circuit optimization is effective only in the region of about ±30% around the reference delay; outside of this region the optimization becomes too costly either in terms of energy or delay. Using optimal energy—delay tradeoffs from the circuit level and introducing more degrees of freedom, the optimization is hierarchically extended to higher abstraction layers. We focus on the micro-architectural optimization and demonstrate that the scope of energy-efficient optimization can be extended by the choice of circuit topology or the level of parallelism. In a 64-bit ALU example, parallelism of five provides a three-fold performance increase, while requiring the same energy as the reference design. Parallel or time-multiplexed solutions significantly affect the area of their respective designs, so the overall design cost is minimized when optimal energy—area tradeoff is achieved. [ABSTRACT FROM AUTHOR]