A 1-year remote sensing study of radiative effects of aerosol and clouds over the NE Mediterranean

Direct aerosol radiative forcing (ARF) and cloud radiative forcing (CRF) over the Aegean Sea are investigated using 1 year of almost continuous observations of aerosol optical properties, cloud data and Clouds and the Earth's Radiant Energy System (CERES) satellite short-wave (SW) and long-wave (LW) fluxes during 2005–2006. Aerosol optical depth (AOD) values from moderate resolution imaging spectroradiometer (MODIS) over the Aegean Sea are found to be high during summer and spring months. This period of the year, the air masses come predominantly from the eastern and northeastern part of Europe. The monthly mean ARF at the top of the atmosphere (TOA) over the Aegean Sea resulted in net cooling and ranged from??6.0 to??15.8 W m^?2, within the range of results from previous studies. The presence of fine particles greatly influenced the ARF. The CRF was also characterized by net cooling and ranged from??23 to??84 W m^?2 and appeared to be driven primarily by changes in cloud fraction. An apparent aerosol weekly cycle with lower values during the weekend as well as a cloud fraction weekly cycle with lower values during the weekend is observed over the Aegean Sea, which, if confirmed, could result in net TOA forcing of around??20 W m^?2.     

A structured autopsy-based audit of 370 firearm fatalities: Contribution to inform policy decisions and the probability of the injured arriving alive at a hospital and receiving definitive care

The objectives of this autopsy-based audit of firearm-related fatalities were to acquire data to inform policy decisions and to assess the probability of the injured arriving alive at a hospital and receiving definitive care.     

Shortest route mobility assisted packet delivery with soft maximum delay guarantees in mobile ad hoc networks

In delay tolerant Mobile Ad hoc Networks (MANETs) node mobility can be exploited in order to reduce the source–destination path lengths in the expense of higher packet delivery delays. This paper addresses the problem of minimizing the average source–destination path length under a maximum delay constraint for packet delivery which is desirable to certain applications. Imposing packet delivery deadlines results in a certain percentage of multi-hop packet transmissions and poses the practical problem of selecting the optimum moment for the transmission. We propose an Optimal Stopping Rule algorithm for solving this problem and show how this algorithm can be extended in the case that a source–destination route is not always available by relaxing the hard delay constraint to a soft (probabilistic) constraint. The performance of this algorithm is compared to the ideal case of scheduling with perfect knowledge of the future and the trade-off between higher allowable delay and lower average path length is illustrated through several Matlab and ns-2 simulation results. As an application of path length minimization we explain how this can lead to energy consumption minimization in a MANET with light traffic loads (low probability of collisions). Finally, we briefly discuss how this path length minimization algorithm can guide the development of cross-layer throughput maximization algorithms with soft maximum delay guarantees.     

Electrochemical behavior of ammonia on Ni98Pd2 nano-structured catalyst

Small amounts of Pd served as a reducing agent to produce sub-100 nm polygonally-shaped Ni₉₈Pd₂ materials in ethylene glycol. As-synthesized particles were crystallized into fcc Ni with a fraction of β-Ni(OH)₂, and exhibited very low to no activity towards ammonia electrooxidation. Their catalytic activity has been significantly improved by building up a layer of Ni(OH)₂ by cyclic voltammetry between −0.95 and 1.35 V vs. HgO/Hg in NaNO₃ at pH 9. XPS analysis before and after the electrochemical treatment confirmed the transformation of Ni⁰ to higher state of oxidation. Ammonia electrooxidation on Ni(OH)₂/NiPd occurred at around 1.28 V vs. HgO/Hg and was highly pH-dependent. At concentrations less than 100 mM, the direct electron transfer took place, whereas at higher ammonia concentrations it was the indirect electron transfer mechanism. A 9-h galvanostatic electrolysis at 20 mA cm⁻² showed that 64% of the initial ammonia was degraded at 38% average current efficiency.     

CPC Solar Collectors With Flat Bifacial Absorbers

The design, construction and test results of non-evacuated stationary CPC solar collectors with flat absorbers are presented and discussed. The proposed collector design is based on a truncated asymmetric CPC reflector, consisting of a parabolic and a circular part. A flat bifacial absorber is installed at the upper part of the collector, parallel to the glazing to form a thermal trap space between the reverse absorber surface and the circular part of the mirror. Two prototypes based on the same collector geometry were constructed and tested. The first model consists of one mirror–absorber unit and the second of three smaller units integrated in one collector device. The truncated CPC mirror and the installation of the absorber parallel to the glazing keep the optical efficiency at a satisfactory level. The reduction of radiative thermal losses by using selective absorbers and the suppression of convection thermal losses from the reverse absorber surface to the collector cover result to a significant decrease of the total collector thermal losses. The experimental results showed that the proposed CPC collector could achieve a maximum efficiency of 0.71 and a stagnation temperature of about 180°C, with the multiunit collector device being more efficient and practical.     

Evaluation of a polymer coating containing triclosan as the antimicrobial layer for packaging materials

Summary A coating made of a styrene‐acrylate copolymer and containing triclosan (87 ± 9 mg triclosan cm^?3 coating) was evaluated as an antimicrobial layer for packaging materials. In both agar diffusion tests and liquid culture tests, inhibition of growth of Enterococcus faecalis by the triclosan‐coating was observed. Triclosan in the coating was not released into the water. Using a solution of 10% aqueous ethanol to simulate aqueous/acidic foods, a very small portion of the triclosan was quickly released with an estimated apparent partition coefficient of 1.7 × 10^?5. When using n‐heptane, to simulate fatty foods, most of the triclosan was extracted with an estimated apparent partition coefficient of 5.5 × 10^?2.     

Continuous-Time Varying Complex QR Decomposition via Zeroing Neural Dynamics

Neural Processing Letters - QR decomposition (QRD) is of fundamental importance for matrix factorization in both real and complex cases. In this paper, by using zeroing neural dynamics method, a...     

Occurrence, virulence genes and antibiotic resistance of Escherichia coli O157 isolated from raw bovine, caprine and ovine milk in Greece

The examination of 2005 raw bovine (n = 950), caprine (n = 460) and ovine (n = 595) bulk milk samples collected throughout several regions in Greece for the presence of Escherichia coli serogroup O157 resulted in the isolation of 29 strains (1.4%) of which 21 were isolated from bovine (2.2%), 3 from caprine (0.7%) and 5 from ovine (0.8%) milk. Out of the 29 E. coli O157 isolates, only 12 (41.4%) could be classified as Shiga-toxigenic based on immunoassay and PCR results. All 12 Shiga-toxigenic E. coli serogroup O157 isolates belonged to the E. coli O157:H7 serotype. All except one of the 12 Shiga-toxin positive isolates were stx₂-positive, five of which were also stx₁-positive. The remaining isolate was positive only for the stx₁ gene. All stx-positive isolates (whether positive for stx₁, stx₂ or stx₁ and stx₂) were also PCR-positive for the eae and ehxA genes. The remaining 17 E. coli O157 isolates (58.6%) were negative for the presence of the H7 flagellar gene by PCR, tested negative for Shiga-toxin production both by immunoassay and PCR, and among these, only four and three strains were PCR-positive for the eae and ehxA genes, respectively. All 29 E. coli O157 isolates displayed resistance to a wide range of antimicrobials, with the stx-positive isolates being, on average, resistant to a higher number of antibiotics than those which were stx-negative.