The temperature dependency of kinetic parameters in p-PbTe and p-CdTe thin films formed on glass substrates has been investigated. The surface mobility of current carriers in PbTe films was computed ...as a function of temperature under the assumption of diffuse scattering of charge carriers. The mechanisms of intergranular current carrier transfer related with thermoelectronic emission are established. The role of surface scattering and intergranular boundaries in thin films of lead and cadmium tellurides is addressed.
Oxygen-free radicals, more generally known as reactive oxygen species (ROS) along with reactive nitrogen species (RNS) are well recognised for playing a dual role as both deleterious and beneficial ...species. The “two-faced” character of ROS is substantiated by growing body of evidence that ROS within cells act as secondary messengers in intracellular signalling cascades, which induce and maintain the oncogenic phenotype of cancer cells, however, ROS can also induce cellular senescence and apoptosis and can therefore function as anti-tumourigenic species. The cumulative production of ROS/RNS through either endogenous or exogenous insults is termed oxidative stress and is common for many types of cancer cell that are linked with altered redox regulation of cellular signalling pathways. Oxidative stress induces a cellular redox imbalance which has been found to be present in various cancer cells compared with normal cells; the redox imbalance thus may be related to oncogenic stimulation. DNA mutation is a critical step in carcinogenesis and elevated levels of oxidative DNA lesions (8-OH-G) have been noted in various tumours, strongly implicating such damage in the etiology of cancer. It appears that the DNA damage is predominantly linked with the initiation process. This review examines the evidence for involvement of the oxidative stress in the carcinogenesis process. Attention is focused on structural, chemical and biochemical aspects of free radicals, the endogenous and exogenous sources of their generation, the metal (iron, copper, chromium, cobalt, vanadium, cadmium, arsenic, nickel)-mediated formation of free radicals (e.g. Fenton chemistry), the DNA damage (both mitochondrial and nuclear), the damage to lipids and proteins by free radicals, the phenomenon of oxidative stress, cancer and the redox environment of a cell, the mechanisms of carcinogenesis and the role of signalling cascades by ROS; in particular, ROS activation of AP-1 (activator protein) and NF-κB (nuclear factor kappa B) signal transduction pathways, which in turn lead to the transcription of genes involved in cell growth regulatory pathways. The role of enzymatic (superoxide dismutase (Cu, Zn-SOD, Mn-SOD), catalase, glutathione peroxidase) and non-enzymatic antioxidants (Vitamin C, Vitamin E, carotenoids, thiol antioxidants (glutathione, thioredoxin and lipoic acid), flavonoids, selenium and others) in the process of carcinogenesis as well as the antioxidant interactions with various regulatory factors, including Ref-1, NF-κB, AP-1 are also reviewed.
In addition to its structural role, the skeleton serves as an endocrine organ that controls mineral metabolism and energy homeostasis. Three major cell types in bone - osteoblasts, osteoclasts, and ...osteocytes - dynamically form and maintain bone and secrete factors with systemic activity. Osteocalcin, an osteoblast-derived factor initially described as a matrix protein that regulates bone mineralization, has been suggested to be an osteoblast-derived endocrine hormone that regulates multiple target organs including pancreas, liver, muscle, adipose, testes, and the central and peripheral nervous system. Sclerostin is predominantly produced by osteocytes, and is best known as a paracrine-acting regulator of WNT signaling and activity of osteoblasts and osteoclasts on bone surfaces. In addition to this important paracrine role for sclerostin within bone, sclerostin protein has been noted to act at a distance to regulate adipocytes, energy homeostasis, and mineral metabolism in the kidney. In this article, we aim to bring together evidence supporting an endocrine function for sclerostin and osteocalcin, and discuss recent controversies regarding the proposed role of osteocalcin outside of bone. We summarize the current state of knowledge on animal models and human physiology related to the multiple functions of these bone-derived factors. Finally, we highlight areas in which future research is expected to yield additional insights into the biology of osteocalcin and sclerostin.
•Designed multilayer was deposited by microwave assisted magnetron sputtering method.•AR coating in designed wavelength range had transmittance higher than 97%.•The AR multilayer was hydrophobic and ...photocatalytically active.•AR coating was scratch resistant.•Deposited multilayer had higher hardness than the glass substrate.
Antireflection (AR) multilayer coating, based on combination of five TiO2 and SiO2 thin films, was deposited by microwave assisted reactive magnetron sputtering process on microscope glass substrates. In this work X-ray diffraction, X-ray photoelectron spectroscopy, atomic force microscopy and wettability measurements were used to characterize the structural and surface properties of the deposited coating. These studies revealed that prepared coating was amorphous with low surface roughness. Photocatalytic properties were determined based on phenol decomposition reaction. Measurements of optical properties showed that transmittance in the visible wavelength range was increased after the deposition of AR coating as-compared to bare glass substrate. The mechanical properties were determined on the basis of nano-indentation and scratch resistance tests. Performed research has shown that deposition of an additional thin 10nm thick TiO2 thin film top layer, the prepared AR coating was photocatalytically active, hydrophobic, scratch resistant and had increased hardness as-compared to bare glass substrate. These results indicate that prepared AR multilayer could be used also as a self-cleaning and protective coating.
To evaluate the efficacy and safety of different doses and regimens of filgotinib, an oral Janus kinase 1 inhibitor, as add-on treatment to methotrexate (MTX) in patients with active rheumatoid ...arthritis (RA) and inadequate response to MTX.
In this 24-week phase IIb study, patients with moderate-to-severe active RA receiving a stable dose of MTX were randomised (1:1:1:1:1:1:1) to receive placebo or 50, 100 or 200 mg filgotinib, administered once daily or twice daily. Primary end point was the percentage of patients achieving a week 12 American College of Rheumatology (ACR)20 response.
Overall, 594 patients were randomised and treated. At week 12, significantly more patients receiving filgotinib 100 mg once daily or 200 mg daily (both regimens) achieved an ACR20 response versus placebo. For other key end points at week 12 (ACR50, ACR-N, Disease Activity Score based on 28 joints and C reactive protein value, Clinical Disease Activity Index, Simplified Disease Activity Index and Health Assessment Questionnaire-Disability Index), differences in favour of 100 or 200 mg filgotinib daily were seen versus placebo; responses were maintained or improved through to week 24. Rapid onset of action and dose-dependent responses were observed for most efficacy end points and were associated with an increased haemoglobin concentration. No significant differences between once-daily and twice-daily regimens were seen. Treatment-emergent adverse event rates were similar in placebo and filgotinib groups. Serious infections occurred in one and five patients in the placebo and filgotinib groups, respectively. No tuberculosis or opportunistic infections were reported.
Filgotinib as add-on to MTX improved the signs and symptoms of active RA over 24 weeks and was associated with a rapid onset of action. Filgotinib was generally well tolerated.
NCT01888874.
Although organic species are transported and efficiently transformed in clouds, more than 60% of this organic matter remains unspeciated. Using GCxGC-HRMS technique we were able to detect and ...identify over 100 semi-volatile compounds in 3 cloud samples collected at the PUY station (puy de Dôme mountain, France) while they were present at low concentrations in a very small sample volume (<25 mL of cloud water). The vast majority (∼90%) of the detected compounds was oxygenated, while the absence of halogenated organic compounds should be specially mentioned. This could reflect both the oxidation processes in the atmosphere (gas and water phase) but also the need of the compounds to be soluble enough to be transferred and dissolved in the cloud droplets. Furans, esters, ketones, amides and pyridines represent the major classes of compounds demonstrating a large variety of potential pollutants. Beside these compounds, priority pollutants from the US EPA list were identified and quantified. We found phenols (phenol, benzyl alcohol, p-cresole, 4-ethylphenol, 3,4-dimethylphenol, 4-nitrophenol) and dialkylphthalates (dimethylphthalate, diethylphthalate, di-n-butylphthalate, bis-(2-ethylhexyl)-phthalate, butylbenzylphthalate, di-n-octyl phthalate). In general, the concentrations of phthalates (from 0.09 to 52 μg L−1) were much higher than those of phenols (from 0.03 to 0.74 μg L−1). To our knowledge phthalates in clouds are described here for the first time. We investigated the variability of phenols and phthalates concentrations with cloud air mass origins (marine vs continental) and seasons (winter vs summer). Although both factors seem to have an influence, it is difficult to deduce general trends; further work should be conducted on large series of cloud samples collected in different geographic areas and at different seasons.
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•The major portion of organic matter in the cloud water remains unknown.•GC-HRMS allowed identifying over 100 organic compounds in the cloud water in France.•Phenols and phthalates levels were reliably quantified.•Phthalates present higher concentrations than phenols in cloud water.
Fragmentation and isolation may have detrimental effects on the viability of populations. Xerothermic grasslands, which are extra‐zonal analogues of steppes, are among Europe's most endangered ...natural environments. Information about connectivity between the remaining habitat patches is critical for effective conservation planning. However, very little is known about the actual levels of isolation of individual xerothermic patches at the inter‐regional and local scale. In this study, 16 microsatellite loci were used to investigate genetic diversity, structuring, effective sizes (Ne), and connectivity among populations of the weevil Centricnemus leucogrammus at various geographic scales. Analysis of 22 populations from three geographic regions, differing in the time of origin and the degree of geographic isolation of the populations, showed that the isolated populations from northern Poland showed the least variability, whereas those from central Poland and Ukraine sustained a similar level of microsatellite variability and were moderately connected within regions. Very low effective sizes (Ne = 14–44) were estimated, and signatures of bottlenecks were detected in all populations. Effective sizes were generally higher in larger xerothermic patches, which constitute a good quality habitat, and in populations sampled in nature reserves, as opposed to unprotected turfs. Such information is useful for the design of conservation and management plans. As C. leucogrammus is characteristic of xerothermic and steppic habitats in central and eastern Europe, it may be considered an excellent target species for assessing the quality of xerothermic habitats as well as estimating and monitoring their connectivity.
A modified surface was obtained on wide-gap II-VI compounds. The methods of thermal annealing for cadmium chalcogenides and chemical etching for the first time obtained heterolayers of atypical ...hexagonal modification of α-ZnSe have been improved. AFM topograms of surface nanostructures have been investigated and comprehensive studies of optical and luminescent properties have been carried out. The emission spectra were determined in the photon energy range 1.4-3.6 eV and the important role of recombination processes in the formation of the A band in the edge region was established. The dominant role of quantum-dimensional processes in the formation of the obtained B band of intense radiation in a wide spectral region of the visible and ultraviolet ranges has been established.
In this work multi-magnetron sputtering stand was used for the deposition of the mixed oxides thin films based on HfO2 and TiO2. In order to obtain various material composition the power released to ...each magnetron (containing metallic hafnium and titanium targets) was precisely selected. Structural, surface, optical, electrical and mechanical properties of as-deposited coatings were analyzed. Depending on the hafnium content in the deposited thin films various types of the microstructure was obtained, i.e. HfO2-monoclinic, amorphous and TiO2-rutile. Increase of Ti content above 28at. % in the as-prepared mixed oxides coatings caused their amorphization. It was found that with an increase of Ti content in prepared coatings their surface roughness and simultaneously water contact angle decreased. Performed measurements of electrical properties revealed that the lowest leakage current density in the range of 10−7–10−8A/cm2 was obtained for amorphous coatings. Moreover, the tailoring of the dielectric constant was possible by a proper selection of material composition and microstructure of the deposited thin films. Average transparency in the visible wavelength region was in the range of ca. 79–86%. The influence of material composition and structure on shifting of the fundamental absorption edge and optical band gap energy was also observed. The refractive index increased with an increase of Ti content, while extinction coefficient was the lowest for amorphous coatings. Additionally, hardness values were dependent on the material composition and optical packing density and were in the range from 7.6GPa to 10.1GPa.
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•Mixed HfO2-TiO2 coatings with Hf:Ti atomic ratios of ca. 70:30, 50:50 and 30:70 were deposited by magnetron sputtering•HfO2, TiO2 and film with Hf:Ti atomic ratio of 70:30 were nanocrystalline with crystallites below 10 nm.•Thin films with Hf:Ti atomic ratios of 50:50 and 30:70 were amorphous.•Amorphous thin films had the lowest leakage current density in the range of 10–7÷10–8 A/cm2 among all deposited coatings.•Amorphous thin films had the smoothest surface, the lowest extinction coefficient and the highest transparency.
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