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Peroxynitrite is a powerful and long-lived oxidant generated in vivo. Peroxynitrous acid (ONOOH), its protonated form, may penetrate into phospholipid bilayers and undergo homolytic cleavage to nitrogen dioxide (·NO2) and hydroxyl radicals (·OH), causing severe nitro-oxidative damage. The membrane environment is thought to influence ONOOH reactions, but the mechanisms remain speculative. Most experimental techniques lack the level of resolution required to keep track of the motion of very reactive species and their interactions with the membrane. Here, we performed molecular dynamics simulations of the permeation, interactions, and dynamics of ONOOH and its homolysis products in the phospholipid membrane environment. We started by developing an ONOOH model that successfully accounted for its conformational equilibria and solvation energies. Membrane permeation of ONOOH was accompanied by conformational changes. ONOOH exhibited a strong tendency to bind to and accumulate at the membrane headgroup region. There, ONOOH homolysis led to ·NO2radicals, which in turn partitioned to the membrane interior. About one-third of the ·OH radicals readily escaped to the aqueous phase within 1 ns. However, a significant number of ·OH radicals became trapped at the lipid headgroup region for a longer period. The possible implications for membrane-based nitration and oxidation processes were discussed.

This paper introduces and studies a unique probability distribution. The maximum likelihood estimation, the ordinary least squares, the weighted least squares, and the Anderson–Darling estimation methods all take into account a number of financial risk indicators, including the value-at-risk, tail-value-at-risk, tail variance, tail mean-variance, and mean excess loss function. These four approaches were used in a simulation study and an application to insurance claims data for the actuarial evaluation. The well-known Nikulin–Rao–Robson statistic is taken into consideration for distributional validation under the whole set of data. Three complete actual datasets and a simulation study are used to evaluate the Nikulin–Rao–Robson test statistic. An updated version of the Nikulin–Rao–Robson statistic is taken into consideration for censored distributional validation. Three censored actual datasets and a thorough simulation analysis are used to evaluate the novel Nikulin–Rao–Robson test statistic.

The presence of pharmaceutical contaminants in aquatic environments has become an issue of huge concern worldwide due to their potential hazardous effects on the aquatic ecosystem, as well as on the health of humans. Bearing that in mind, in the last years we have seen an intense development of novel highly efficient, cost-effective, and sustainable treatment techniques for the degradation of these contaminants. Here, we present a comprehensive literature review on studies conducted over the past five years on pharmaceutical focusing on their ecotoxicological effects, as well as on the research efforts devoted to the development and application of sustainable technologies for the detoxification of a wide range of waters contaminated with these compounds. With these developments, this review look at the future perspectives on the subject and the constraints and challenges faced by researchers in terms of devising highly innovative techniques which can effectively contribute toward enhancing the efficiency of the treatment. According to the review, just a few studies worked in realistic scenarios (23.4%) including real water and contaminant concentrations close to levels detected in the environment. Regarding scale-up considerations, only 6% of studies applied the techniques on a large scale. The importance of economic considerations in the proposed techniques is also discussed in the following directions: (i) use of renewable energy sources; (ii) development of more cost-effective hybrid processes and (iii) simultaneous removal of other toxic inorganic species, by-products and microorganisms.

We have studied thin films of the conjugated polymer poly2-methoxy-5-(2‘-ethylhexyloxy)-1,4-phenylenevinylene (MEH-PPV), prepared from polymer samples whose weight-average molecular weight (Mw) was varied in the broad range of 10-1600 kg/mol. Anisotropic refractive index measurements by means of waveguide prism coupling and reflectometry as well as polarized infrared spectroscopy were used to analyze the polymer chain orientation in the films. We found that the film morphology depends significantly on the molecular weight, especially in the range Mw< 400 kg/mol. Thin films of high molecular weight MEH-PPV have most polymer chain segments oriented parallel to the film planein contrast to low molecular weight samples which have nearly random orientation of the chain segments. Appropriate choice of molecular weight enables fine-tuning of the refractive index of slab waveguides and reduction of their mode propagation losses to less than 1 dB/cm.

Bluetooth is a radio technology for Wireless Personal Area Networking (WPAN) operating in the 2.4 GHz ISM frequency band. So far, there has been little research on how Bluetooth-enabled devices can effectively and efficiently have uninterrupted access to wide area networks (WAN) such as the Internet. We introduce a novel architecture (BlueStar) whereby selected Bluetooth devices, called Bluetooth Wireless Gateways (BWGs), are also IEEE 802.11 enabled so that these BWGs could serve as egress/ingress points to/from the IEEE 802.11 wireless network. We propose mitigating interference between Bluetooth and IEEE 802.11, by employing a hybrid approach of adaptive frequency hopping (AFH) and Bluetooth carrier sense (BCS) of the channels. AFH labels channels as “bad” or “good”, and Bluetooth devices only access those channels in the “good” state, whereas BCS is used to avoid collision by sensing the channel prior to any transmission. By combining AFH and BCS, we drastically minimize the effect of the worst-case interference scenario wherein both a Bluetooth and an IEEE 802.11 interface are co-located in a single device. BlueStar enables Bluetooth devices, belonging to either a piconet or a scatternet, to access the WAN through the BWG without the need for any fixed Bluetooth access points, while utilizing widely deployed base of IEEE 802.11 networks. Moreover, we define the protocol stack employed by BlueStar as well as indicate how BWGs efficiently manage their capacity allocation through the different systems. We also mathematically derive an upper bound on the number BWGs needed in a Bluetooth scatternet so that uninterrupted access to all Bluetooth devices could be provided.

A novel ZnII complex bearing two monodentate (4-methoxyphenyl)[(1E, 2E)-3-phenylprop-2-en-1-ilidene] Schiff bases was synthesized and investigated both in the solid state by single-crystal X-ray diffraction, elemental analysis, and FTIR and in solution by 1H NMR spectroscopy. The complex crystallizes in the P21/c monoclinic space group. The asymmetric unit contains one ZnII ion coordinated to two Schiff base ligands and two chloride ions, in a distorted tetrahedral geometry. The title complex was also investigated by DFT, using the hybrid functional B3LYP with basis set 6-31G++, which reproduced the geometry and structural features of the complex in the crystal, and was used to assign the main bands in the FTIR spectrum. In solution, the complex maintains its integrity against decomposition to the parent reagents.