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Shape-controlled synthesis of noble metal nanoparticles and their impact on the photocatalytic activity of semiconductor oxides is continuously gaining more and more attention. Hence, commercial titania-based TiO 2 -Pd nanocomposites were synthetized and characterized, using spherical and cubical Pd nanoparticles. The obtained photocatalysts were analyzed using optical (DRS) as well as morphological and structural (XRD, HR-TEM) methods in order to understand their properties. The effects of the Pd nanoparticles’ shape on different commercial titania-based catalysts were highlighted in terms of photocatalytic efficiencies toward model organic pollutants (phenol and oxalic acid), evolution of reaction intermediates (hydroquinone, pyrocatechol and resorcinol) and photocatalytic H 2 production. It was found that both geometries (spherical, cubic) can enhance the activity of the base photocatalyst, although each Pd morphology modified the ratio of the primary degradation intermediates. Moreover, the photocatalytic hydrogen production of the spherical nanoparticles proved to be more efficient as the cubic ones. The observed activity differences were attributed to a possible change in the electron-transfer process, induced by the different Pd morphologies. [ABSTRACT FROM AUTHOR]

Highlights: [•] The intermediates’ formation is dependent from the synthesis pathway. [•] Bulk-structural aspects influenced the intermediates: crystallinity grade, doping. [•] Surface-structural aspects governed the intermediates: W and Ti species. [•] The gold's deposition wavelength had a major impact on the WO3 structure. [•] The intermediates’ formation can be manipulated by the ratio of different species. [Copyright &y& Elsevier]

Abstract: Polycrystalline uracil thin layer can be used as biological dosimeter for assessing exposure to UV radiation. The dimerization and reversion efficiency of the ultraviolet radiation in the UV-B and the UV-C range were quantified on polycrystalline uracil thin layers irradiated with quasi-monochromatic radiation using interference filters of 10nm bandwidth. The dimer formation and monomerization (reversion) dose–effect relations were determined by optical spectroscopy. The decrease of the OD value of the uracil thin layer at 288nm was taken as a measure of the dimer formation, while the increase of the OD of a completely irradiated (until reaching the saturation level) uracil layer was taken as the sign of the monomerization. The two processes in the UV-B and the UV-C range take place simultaneously, the individual characterization of the dimerization efficiency was performed from the initial slope of the dimerization dose–effect function and an action spectrum for dimerization was constructed in the UV-C range too. The reversion efficiency was found to be practically the same with all of the investigated wavelengths: 200nm, 210nm, 220nm, 230nm, 240nm The possible biological relevance of the reversion of dimers are discussed. [Copyright &y& Elsevier]

Abstract: To fulfil the increasing demands today the short innovation time and the high quality of production itself is not enough in production of goods, but all phases of a product (from idea to recycling) should be managed by advanced tools and means. Nowadays the competition among companies, joined to the environmental protection rules, is so compelling that they should not only be on the top of technology in the area, but also run their business according to life-long models. The emphasis on the product post-sale life is common for these models. The most popular model is Product Life-cycle Management, for manufacturing companies, or Service Engineering (SE), for service-oriented companies, and, for both, common paradigms are in maintenance, with conformance-to-use certification. The paper introduces some basic research results achieved in the application of Ambient Intelligence, and suggests considering maintenance as a cross section of the two business paradigms. The importance of SE is specially underlined in this work. [Copyright &y& Elsevier]

Abstract: Standardized languages used for protocol specification provide an excellent basis for both automatic and manual test generation. Test generation is composed of two steps, the derivation of test cases from the specification, and the selection of the test cases to be included in the final test suite in order to reduce its execution time. This article proposes a new method that aims to decrease the total number of test cases generated automatically by a test derivation algorithm and at the same time to reduce the computation requirements for the test selection procedure. It creates an iteration cycle on the model of evolutionary algorithms, where the test derivation and selection are done simultaneously. In each cycle first a “small” test suite is derived then optimized, evaluated and finally compared to the best suite so far. It is kept as the best suite, if it is found better according to some well-defined evaluation criteria and test suite metrics. This iteration condition is based on the test selection criteria. The article presents an experiment where iterative algorithms are compared to two simple test derivation methods from different aspects. [Copyright &y& Elsevier]

To determine the trends in the utilization of different techniques of radiation treatment in localized uveal melanoma in the United States and to determine the difference in outcome between brachytherapy (BT) and proton-beam therapy (PT). Using the North American Association of Central Cancer Registries (NAACCR), we identified 17451 patients with localized uveal melanoma with known both surgical and method of radiation therapy between 1995-2018. Univariate and multivariable analyses were performed to identify factors and characteristics that may have a potential impact on the treatment. Net survival was calculated using Relative survival in Ederer II cumulative expected method with actuarial. Overall survival (OS) and cancer-specific survival (CSS) were estimated by Kaplan-Meier method and life-tables. The registries included 28.312 patients with uveal melanoma, out of them 22,983 patients with localized disease. Patients with known both surgical and method of radiation therapy were 17451 patients. We have studied this group further. The median age of this group was 61 (IQR 51-71), males were 51.9% (N = 9063), whites were 98.1% (N = 16921), and choroidal tumors were 87.8% (N = 15330). The median tumor thickness was 3.9mm (IQR 24-70), while, the median maximum tumor diameter was 11.3mm (IQR 8.0-14.4). The median follow-up time was 5.9 years (IQR 3.1-10.3). Among all patients, 57.5% (n = 10032) received BT, and 9.8% (n = 1708) received PT. Collectively, 30.1% (n = 5247) of the patients received no radiation treatment. BT constituted 14% of treatment modalities in 1995 and steadily increased to 65% in 2017. PT utilization was minimal in 1995 (1.4%) and also increased to 14.3% in 2017. Younger age and thinner tumor thickness were independently associated with better Cancer-specific survival (CSS) and overall survival (OS). For all patients who were treated primarily with radiation treatment, the 5-year OS was 85,9% and the 10-year OS was 77.2%. There were no differences in rates of OS or CSS between patients who were treated with BT or PT. There is a continuous increase in the utilization of both BT and PT in the treatment of localized uveal melanoma. Similar survival outcomes could be anticipated for both radiation treatment techniques. [ABSTRACT FROM AUTHOR]

Diabetes is one of the most common chronic diseases worldwide. Among diabetic patients eating disorders are not uncommon, one of the most frequent is night eating. [Extracted from the article]

The photocatalytic activity of TiO 2 photocatalysts depends mainly on its crystal phase composition, primary particle size and specific surface area. Shape manipulation is an interesting way to increase the photocatalytic efficiency. The shape-tuning can be carried out at different levels, both at single crystal and polycrystalline agglomeration levels. The aim of our present study was to compare the structural and photocatalytic performances of two type/level of crystal organization of TiO 2 , namely single crystal shaping vs. polycrystalline/shape tailored agglomeration. The morphological analysis was achieved by XRD, SEM, TEM, Raman spectroscopy, DRS. The photocatalytic performance of the materials was evaluated by the degradation of a model pollutant (phenol). It was found, that both shape manipulating approaches bear the necessary potential which can be exploited in future development of efficient photocatalysts’ synthesis procedures. [ABSTRACT FROM AUTHOR]

Highlights: [•] The intermediates’ formation is dependent from the synthesis pathway. [•] Bulk-structural aspects influenced the intermediates: crystallinity grade, doping. [•] Surface-structural aspects governed the intermediates: W and Ti species. [•] The gold's deposition wavelength had a major impact on the WO3 structure. [•] The intermediates’ formation can be manipulated by the ratio of different species. [ABSTRACT FROM AUTHOR]

Abstract: Titania/tungsten (VI) oxide/noble metal (gold and platinum) composites were obtained by the means of selective noble metal photodeposition on the desired oxide's surface (either on TiO2 or on WO3). The noble metal particles’ localization was proved by SEM-EDX, while their size with DRS and TEM. The influence of the noble metal nanoparticles’ position was investigated successfully on the light absorption properties, photocatalytic activity toward oxalic acid and photocatalytic hydrogen production. Major differences were observed in the photocatalytic performance of the catalysts in which only the position of the noble metal was changed. Consequently, highly active composites were obtained, that surpassed the reference catalysts’ (TiO2(Au), TiO2(Pt), WO3(Au), WO3(Pt)) oxalic acid degradation yield and were also quite active for photocatalytic hydrogen production. [Copyright &y& Elsevier]

Abstract: The experiment “Phage and uracil response” (PUR) will be accommodated in the EXPOSE facility of the ISS. Bacteriophage T7/isolated T7 DNA will be exposed to different subsets of extreme environmental parameters in space, in order to study the Responses of Organisms to the Space Environment (ROSE). Launch into orbit is preceded by EXPOSE Experiment Verification Tests (EVT) to optimize the methods and the evaluation. Bacteriophage T7/isolated T7 DNA thin layers were exposed to vacuum (), to monochromatic (254nm) and polychromatic (200–400nm) UV radiation in air as well as in simulated space vacuum. Using neutral density (ND) filters dose-effect curves were performed in order to define the maximum doses tolerated. The effect of temperature fluctuation in vacuum was also studied. The structural/chemical effects on bacteriophage T7/isolated T7 DNA were analyzed by spectroscopic and microscopical methods. Characteristic changes in the absorption spectrum and in the electrophoretic pattern of phage/DNA have been detected indicating the damage of isolated and intraphage DNA. DNA damage was also determined by quantitative PCR (QPCR) using 555 and 3826bp fragments of T7 DNA. We obtained substantial evidence that DNA lesions (e.g. strand breaks, DNA-protein cross-links, cyclobutane pirimidine dimers (CPDs) etc.) accumulate throughout exposure. Preliminary results suggest a synergistic action of space vacuum and UV radiation with DNA being the critical target. [Copyright &y& Elsevier]

Abstract: The experiment “Phage and Uracil response” will be accommodated in the EXPOSE facility of the International Space Station. Its objective is to examine and quantify the effect of specific space conditions on nucleic acid models, especially on bacteriophage T7 and isolated T7 DNA thin films. In order to define the environmental and technical requirements of the EXPOSE, the samples were subjected to the experiment verification test (EVT). During EVT, the samples were exposed to vacuum (10−4–10−6 Pa) and polychromatic UV-radiation (200–400 nm) in air, in inert atmosphere, as well as in simulated space vacuum. The effect of extreme temperature in vacuum and the influence of temperature fluctuations around 0°C were also studied. The total intraphage/isolated DNA damage was determined by quantitative PCR using 555 and 3826bp fragments of T7 DNA. The type of the damage was resolved using a combination of enzymatic probes and neutral and alkaline agarose gel electrophoresis; the structural/chemical effects were analyzed by spectroscopic and microscopical methods. We obtained substantial evidence that DNA lesions accumulate throughout exposure, but the amount of damage depends on the thickness of the layers. According to our preliminary results, the damages by exposure to conditions of dehydration and UV-irradiation are larger than the sum of vacuum alone, or radiation alone case, suggesting a synergistic action of space vacuum and UV radiation with DNA being the critical target. [Copyright &y& Elsevier]

The main goal of PUR experiment (phage and uracil response) is to examine and quantify the effect of specific space conditions on nucleic acid models. To achieve this an improved method was elaborated for the preparation of DNA and bacteriophage thin films. The homogeneity of the films was controlled by UV spectroscopy and microscopy. To provide experimental evidence for the hypothesis that interplanetary transfer of the genetic material is possible, phage T7 and isolated T7 DNA thin films have been exposed to selected space conditions: intense UVC radiation (λ=254 nm) and high vacuum (10-4 Pa). The effects of DNA hydration, conformation and packing on UV radiation damage were examined. Characteristic changes in the absorption spectrum, in the electrophoretic pattern of DNA and the decrease of the amount of PCR products have been detected indicating the photodamage of isolated and intraphage DNA. [Copyright &y& Elsevier]

Polycrystalline uracil thin layers participate in the phage and uracil response (PUR) experiment, assigned to the biological dosimetry of the extraterrestrial solar radiation on the International Space Station (ISS). In ground based experiments (experiment verification tests), the following space parameters were simulated and studied: temperature, vacuum and short wavelength UV (UV-C, down to 200 nm) radiation. The closed uracil samples proved to be vacuum-tight for 7 days. In the tested temperature range (from -20 to +40 °C) the uracil samples are stable. The kinetic of dimer formation (dimerization) and reversion (monomerization) of uracil dimers due to short wavelength UV radiation was detected, the monomerization efficiency of the polychromatic deuterium lamp is higher than that of the germicidal lamp. A mathematical model describing the kinetic of monomerization–dimerization was constructed. Under the influence of UV radiation the dimerization–monomerization reactions occur simultaneously, thus the additivity law of the effect of the various wavelengths is not applicable. [Copyright &y& Elsevier]