Impairment of cellular immunity in west Greenland sledge dogs (Canis familiaris) dietary exposed to polluted minke whale (Balaenoptera acutorostrata) blubber

Minke whale (Balaenoptera acutorostrata) blubber is rich in organohalogen contaminants, mercury, and n-3 fatty acids. In the present study we show that a daily intake of 50-200 g of minke whale blubber causes an impairment of the nonspecific and specific cellular immune system in the West Greenland sledge dog (Canis familiaris). Immune reactions were measured by mitogen (PHA, Con A) and antigen (KLH) intradermal testing, and as the study used exposure levels similar to those of Inuits and polar bears (Ursus maritimus), it is reasonable to infer that Inuits and polar bears suffer from similar decreased resistance to diseases. It is speculated that food sources are depleted by thinning sea ice due to climate change and that more research should assess the forecasted rise in additive immunopathy effects in polar bears. Additionally, our study suggests that the fatty acid composition may be of importance when investigating combined immunotoxic effects of contaminated food resources in future Inuit and polar bear studies.     

A comparative study on physicochemical properties of hydroxyapatite powders derived from natural and synthetic sources

Hydroxy apatite (HA) is effectively used as a bioimplant material because it closely resembles bone apatite and exhibits good biocompatibility. So, in this research, HA powders were produced by calcinations of natural bones including human, bovine, camel and horse bones, and also via sol-gel method. Powders characterizations of natural HA and Synthetic HA were studied by X-ray powder diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM), combined with transmission electron microscopy (ТЕМ). In order to verify the biocompatibility of these HA powders, MTT assay was applied. The XRD results showed that the HA powders were successfully produced by using different sources. Also, it was obvious from XRF analysis that the main components of them were Ca and P. Furthermore, it was seen that the size of particles was in the nanometric scale and they showed agglomerates consisting of numerous nanocrystals. FTIR spectra of all samples proved the presence of various CO ₃ ^2- , PO ₄ ^3- and OH^– groups in the powders. In addition, the MTT assay revealed that the cells proliferations in the presence of horse and human HA nanopowders were stimulated.     

The effect of renewable energy and urbanization on CO2 emissions: A panel data

Europe has experienced fast-paced urbanization development over the past three decades. This paper empirically investigates the long-run equilibrium relationships and causal relationships among urbanization, renewable energy consumption, and CO₂ emissions, and this is important for EU countries’ future sustainable development. DOLS and FMOLS approaches are used for the period 1992–2014 .

Granger causality results show that there is a unidirectional relationship from CO₂ emissions to urbanization, and there is no causality between renewable energy consumption and CO₂ emissions. The results have important implications for EU policymakers on the path toward a sustainable society. Urbanization can have negative impacts on the natural environment with the net effect being hard in EU countries.     

The renewable energy,CO2 emissions,and economic growth: VAR model

This paper provides an empirical analysis of CO₂ emissions and economic growth, renewable energy consumption, and energy consumption over the period 1975–2014 in Germany. This paper uses the autoregressive distributed lag (ARDL) approach of cointegration test and vector error-correction models. The unit root and cointegration tests show that the long-run relationship between CO₂ emissions and its determinants. The empirical results show that the findings do not support the environmental Kuznets curve between real GDP and CO₂ emissions. To estimate the shocks of renewable energy consumptions, the study applies the dynamic test of Impulse Response Function (IRF) under the VAR method. The increasing portion of renewable energy consumption in electricity generation would have no impacts on the environment. However, the hikes of renewable energy sources would incur more cost to electricity producers and shrivel up the growth of economies through the expansionary effect of industry’s consumption and private capital spending in the Germany’s economy.     

An ultra-energy-efficient crosstalk-immune interconnect architecture based on multilayer graphene nanoribbons for deep-nanometer technologies

An ultra-energy-efficient interconnect structure based on multilayer graphene nanoribbon (MLGNR) interconnects for deep-nanometer technologies is proposed herein. First, a low-swing interconnect based on MLGNRs and high-performance interface circuits using carbon nanotube field-effect transistors (CNTFETs) is proposed. Then, an ultra-energy-efficient interconnect structure is obtained by actively shielding such low-swing lines. The structures under study are simulated comprehensively at the 7-nm technology node. The results indicate that the MLGNR interconnect is significantly more energy efficient than its multiwall carbon nanotube (MWCNT) counterpart in the low-voltage regime. Moreover, the proposed approach is superior to its MLGNR counterparts. The proposed structure leads to 86%, 75%, and 31% lower energy consumption over a length of 500 µm as compared with the typical, actively shielded, and low-swing MLGNR interconnects, respectively. Moreover, the impact of the ratio of the widths of the signal line to the shield line on the performance of the interconnects is evaluated. The energy consumption reduction achieved by the proposed approach is mostly preserved even when using minimum-width shield lines on wider signal lines to reduce the area overhead. Moreover, the impact of process variations on the performance of the interconnects is assessed using Monte Carlo simulations, demonstrating the robustness of the proposed approach.

     

Ultrasound-assisted extraction of bioactive compounds from <Emphasis Type="Italic">Malva sylvestris</Emphasis> leaves and its comparison with agitated bed extraction technique

The effects of ultrasound-assisted extraction (UAE) variables—namely extraction temperature (40–60 °C), ultrasonic power (50–150 W), and sonication time (40–60 min)—on the extractive value (EV) of bioactive phenolics from Malva sylvestris leaves were investigated and optimized using Response surface methodology. The effects of extraction solvents (ethanol, ethyl acetate, and n-hexane) on EV, free radical scavenging activity (FRSA), total phenolic content (TPC), and major bioactive phenolics were studied using agitated bed extraction (ABE), and the results were compared with the UAE findings. Under the optimal UAE conditions (48 °C, 110.00 W, and 48.77 min) the experimental EV was 279.89 ± 0.21 mg/g with 71.12 ± 0.15% DPPH_sc, 73.35 ± 0.11% ABTS_sc, and a TPC of 152.25 ± 0.14 mg GAE/g. Ethanolic ABE results in higher EV (320.16 ± 0.25 mg g^?1) compared to UAE, while the FRSA and TPC values were reduced. HPLC analysis revealed that the concentration of bioactive phenolics increased significantly (p < 0.05) under the optimal UAE conditions.     

The effect of isopropanol addition on enhancement of transdermal controlled release of ibuprofen from ethylene vinyl acetate copolymer membranes

This work reports the study of the addition of isopropanol on controlled release of ibuprofen from ethylene vinyl acetate (EVAc) copolymer membranes. An EVAc solution in cyclohexane (4% w/v) containing triethyl citrate (7% w/v) as plasticizer was mixed with ibuprofen at three different concentrations of 4, 6, and 8%. Isopropanol was mixed with each of the previous mixtures to form solutions of 1, 3, and 5% isopropanol concentrations. Samples were solvent cast on glass petri‐dishes to form membranes. Home‐made diffusion cells were used for in vitro study. These cells were composed of two compartments, donor (exposed to ambient conditions), and receptor (including buffer solution maintained at 37°C). Each cell was equipped with a sampling port and water in and out system. An ultraviolet spectrometer at 222 nm was used to measure release rates of obtained membranes. The diffusion mechanism for drug release was examined by zero‐order, first‐order, Higuchi and Korsmeyer‐Peppas theories to confirm the obtained membranes follow the matrix‐type system. By increasing the drug concentration from 4 to 8%, drug release (cumulative amount) was improved from 20 (47.5%) to 30 (36%) μg/cm² after 24 h. Addition of 5% isopropanol to the above samples (4 and 8% loading) further increased drug release to 24 and 43 μg/cm². Results were in good agreement with the Korsmeyer‐Peppas theory for samples with 4 (% w/w) of ibuprofen. The highest percentage of drug release after 24 h was 59% for the sample with 4% drug loading compared to 50% for the sample with 8% drug loading, both with 5% isopropanol. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Comparative study on the corrosion and wear behavior of plasma-sprayed vs. high velocity oxygen fuel-sprayed Al8Si20BN ceramic coatings

Corrosion and wear are common problems encountered in the oil and gas industry. These entail the gradual destruction of materials by mechanical action on the opposite surface, and the chemical and/or electrochemical reaction with their environment. In this research, Al8Si20BN ceramic powder with specific properties against corrosion and wear was selected, and it was sprayed with high velocity oxygen fuel (HVOF) and plasma spray methods onto carbon steel substrates. The coatings were characterized with respect to phase composition, microstructure, microhardness and adhesion strength. Their wear behavior was inspected by applying 5, 10, 15 and 20?N loads by pin-on-disc machine, after which the results of both methods were compared. According to the results, the HVOF-coated models were more durable than the plasma-coated models under different loads in the same condition. In addition, the corrosion deterioration of the coated specimens in both brine (3.5% NaCl) and fossil oil were tested for one month (30 days). Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) assessment in 3.5% NaCl solution indicated that the HVOF-sprayed specimens had better corrosion protection than the plasma-sprayed specimens. Generally, the HVOF technique facilitated more durable coats with greater corrosion and tribological resistance compared to the plasma coating technique.     

Fault tolerant control using virtual actuator for continuous‐time Lipschitz nonlinear systems

In this brief, we extend the existing results on fault tolerant control via virtual actuator approach to a class of systems with Lipschitz nonlinearities to maintain the closed‐loop stability after actuator faults. This generalization is established by relying on the input‐to‐state stability properties of cascaded systems. The virtual actuator block, placed between faulty plant and nominal controller, generates useful input signals for faulty plant by using output signals of the nominal controller to guarantee the closed‐loop stability in the presence of actuator faults. This design problem is reduced to a matrix inequality that can be turned to an LMI by fixing a variable to a constant value and solving the resulting LMI feasibility problem. The proposed fault tolerant control method is successfully evaluated using a nonlinear system. Copyright © 2013 John Wiley & Sons, Ltd.     

Water-Stable Fluorous Metal–Organic Frameworks with Open Metal Sites and Amine Groups for Efficient Urea Electrocatalytic Oxidation

Urea oxidation reaction (UOR) is one of the promising alternative anodic reactions to water oxidation that has attracted extensive attention in green hydrogen production. The application of specifically designed electrocatalysts capable of declining energy consumption and environmental consequences is one of the major challenges in this field. Therefore, the goal is to achieve a resistant, low-cost, and environmentally friendly electrocatalyst. Herein, a water-stable fluorinated Cu(II) metalorganic framework (MOF) {[Cu₂(L)(H₂O)₂]·(5DMF)(4H₂O)}_n (Cu-FMOF-NH₂; H₄L = 3,5-bis(2,4-dicarboxylic acid)-4-(trifluoromethyl)aniline) is developed utilizing an angular tetracarboxylic acid ligand that incorporates both trifluoromethyl (–CF₃) and amine (–NH₂) groups. The tailored structure of Cu-FMOF-NH₂ where linkers are connected by fluoride bridges and surrounded by dicopper nodes reveals a 4,24T1 topology. When employed as electrocatalyst, Cu-FMOF-NH₂ requires only 1.31 V versus reversible hydrogen electrode (RHE) to deliver 10 mA cm⁻² current density in 1.0 m KOH with 0.33 m urea electrolyte and delivered an even higher current density (50 mA cm⁻²) at 1.47 V versus RHE. This performance is superior to several reported catalysts including commercial RuO₂ catalyst with overpotential of 1.52 V versus RHE. This investigation opens new opportunities to develop and utilize pristine MOFs as a potential electrocatalyst for various catalytic reactions.