Improved low-contrast retinal recognition using compression-based joint wavelet transform correlator

Retinal recognition by using compression-based joint wavelet transform correlator (CBJWTC) is proposed in order to solve poor contrast problem of fundus images. The simulation results show that by using a wavelet filter dilated at a proper dilation, the CBJWTC offers better recognition performance than the conventional JTC, regardless of the reference contrast.     

IEEE 802.11 Wireless Local Area Networks

The draft IEEE 802.11 wireless local area network (WLAN) specification is approaching completion. In this article, the IEEE 802.11 protocol is explained, with particular emphasis on the medium access control sublayer. Performance results are provided for packetized data and a combination of packetized data and voice over the WLAN. Our performance investigation reveals that an IEEE 802.11 network may be able to carry traffic with time-bounded requirements using the point coordination function. However, our findings suggest that packetized voice traffic must be handled in conjunction with an echo canceler     

Lymphocyte response to tetanus toxoid among Indonesian men immunized with tetanus-diphtheria during extended chloroquine or primaquine prophylaxis

Immune suppression, a potential side effect of long-term chemoprophylaxis, was evaluated as part of a randomized, placebo-controlled trial that compared daily primaquine against weekly chloroquine for malaria prevention. In the last month of the year-long trial, baseline in vitro lymphoproliferative responses to tetanus toxoid were measured, and a tetanus-diphtheria (Td) immunization was administered. Proliferative responses to tetanus toxoid in each Td-immunized group increased significantly over pre-Td baselines and those of the unvaccinated control. Highest initial responses were measured in the primaquine group. The proportion of responders and the magnitude of proliferation was consistently low in the chloroquine group, and end point responses in this group were significantly below those of the placebo. These results suggest that the development and duration of the cellular response to tetanus immunization was impaired by long-term weekly chloroquine prophylaxis, while daily primaquine prophylaxis over the same time period had no inhibitory effect.     

Factors affecting the performance of internal control task team in high-tech firms

The rise of global trade and economic development is not only apparently grown in terms of volume but with value as well. Such spurt has evoked the risk management that is associated with export business, and can allow high-tech items fall into the hands of foreign military programs or terrorist organizations. The internal control compliance for export has set the in-house procedures for firms to adopt, facilitate, and abide with defined national export control requirements. This is crucial for firms to prevent potential violations on export rules and regulations. Introducing internal control program for export compliance can mitigate terrorist activities. This present study has taken Taiwan on board to determine the acquaintance of export risk and the implementation of internal control program through a team effort. Hence, the purpose of this study is to investigate the factors affecting the performance of internal control task team within a firm. The findings show that team-based incentives have a positive impact on team cohesion while knowledge sharing and knowledge integration have a significant impact on team performance. Furthermore, it is found that higher social-related risks and technical-related risks may increase team management risk, and the reduction in team management risk is beneficial to improve team performance.     

Preparation of nanosized Mn3O4/SBA-15 catalyst for complete oxidation of low concentration EtOH in aqueous solution with H2O2

A new heterogeneous Fenton-like system consisting of nano-composite Mn₃O₄/SBA-15 catalyst has been developed for the complete oxidation of low concentration ethanol (100 ppm) by H₂O₂ in aqueous solution. A novel preparation method has been developed to synthesize nanoparticles of Mn₃O₄ by thermolysis of manganese (II) acetylacetonate on SBA-15. Mn₃O₄/SBA-15 was characterized by various techniques like TEM, XRD, Raman spectroscopy and N₂ adsorption isotherms. TEM images demonstrate that Mn₃O₄ nanocrystals located mainly inside the SBA-15 pores. The reaction rate for ethanol oxidation can be strongly affected by several factors, including reaction temperature, pH value, catalyst/solution ratio and concentration of ethanol. A plausible reaction mechanism has been proposed in order to explain the kinetic data. The rate for the reaction is supposed to associate with the concentration of intermediates (radicals: OH, O₂⁻ and HO₂) that are derived from the decomposition of H₂O₂ during reaction. The complete oxidation of ethanol can be remarkably improved only under the circumstances: (i) the intermediates are stabilized, such as stronger acidic conditions and high temperature or (ii) scavenging those radicals is reduced, such as less amount of catalyst and high concentration of reactant. Nevertheless, the reactivity of the presented catalytic system is still lower comparing to the conventional homogenous Fenton process, Fe²⁺/H₂O₂. A possible reason is that the concentration of intermediates in the latter is relatively high.     

One‐Step Fabrication of Triple‐Layered Polymeric Microparticles with Layer Localization of Drugs as a Novel Drug‐Delivery System

Particulate systems have tremendous potential to achieve controlled release and targeted delivery of drugs. However, conventional single‐layered particles have several inherent limitations, including initial burst release, the inability to provide zero‐order release, and a lack of time‐delayed or pulsatile release of therapeutic agents. Multilayered particles have the potential to overcome these disadvantages. Herein, it is shown how triple‐layered polymeric microparticles can be fabricated through a simple, economical, reliable, and versatile one‐step solvent evaporation technique. Particle morphologies and layer configurations are determined by scanning electron microscopy, polymer dissolution tests, and Raman mapping. Key fabrication parameters that affect the formation of triple‐layered polymeric microparticles comprising poly(DL ‐lactide‐co‐glycolide) (50:50), poly(L ‐lactide), and poly(ethylene‐co‐vinyl acetate) (40 wt% vinyl acetate) are discussed, along with their formation mechanisms. Layer thickness and the configurations of these microparticles are altered by changing the polymer mass ratios. Finally, it is shown that drugs can be localized in specific layers of the microparticles. This fabrication process can therefore be used to tailor microparticle designs, thus allowing such “designer” particulate drug‐delivery systems to function across a wide range of applications.     

Hepatocyte Specific gp130 Signalling Underlies APAP Induced Liver Injury

N-acetyl-p-aminophenol (APAP)-induced liver damage is associated with upregulation of Interleukin-11 (IL11), which is thought to stimulate IL6ST (gp130)-mediated STAT3 activity in hepatocytes, as a compensatory response. However, recent studies have found IL11/IL11RA/gp130 signaling to be hepatotoxic. To investigate further the role of IL11 and gp130 in APAP liver injury, we generated two new mouse strains with conditional knockout (CKO) of either Il11 (CKO^Il11) or gp130 (CKO^gp130) in adult hepatocytes. Following APAP, as compared to controls, CKO^gp130 mice had lesser liver damage with lower serum Alanine Transaminase (ALT) and Aspartate Aminotransferase (AST), greatly reduced serum IL11 levels (90% lower), and lesser centrilobular necrosis. Livers from APAP-injured CKO^gp130 mice had lesser ERK, JNK, NOX4 activation and increased markers of regeneration (PCNA, Cyclin D1, Ki67). Experiments were repeated in CKO^Il11 mice that, as compared to wild-type mice, had lower APAP-induced ALT/AST, reduced centrilobular necrosis and undetectable IL11 in serum. As seen with CKO^gp130 mice, APAP-treated CKO^Il11 mice had lesser ERK/JNK/NOX4 activation and greater features of regeneration. Both CKO^gp130 and CKO^Il11 mice had normal APAP metabolism. After APAP, CKO^gp130 and CKO^Il11 mice had reduced Il6, Ccl2, Ccl5, Il1β, and Tnfα expression. These studies exclude IL11 upregulation as compensatory and establish autocrine, self-amplifying, gp130-dependent IL11 secretion from damaged hepatocytes as toxic and anti-regenerative.     

Oxidation of methane over Pd/mixed oxides for catalytic combustion

Palladium catalysts supported on mixed oxides (Pd/Al₂O₃–MO_x; M=Co, Cr, Cu, Fe, Mn, and Ni) were investigated for the low-temperature catalytic combustion of methane. Although the surface area decreased with increasing NiO in Pd/mAl₂O₃–nNiO, Pd/Al₂O₃–36NiO demonstrated an excellent activity due to the small particle size of palladium. Also, the catalytic activity strongly depended on the composition of the support. Temperature-programmed desorption of oxygen revealed that the catalytic activity in the low-temperature region depends on the adsorption state of oxygen on palladium. The activity was enhanced when the amount of adsorbed oxygen increased. In-situ XRD analysis indicated that the PdO phase was thermally stabilized on Pd/Al₂O₃–36NiO.     

Performance issues in VC-merge capable switches for multiprotocollabel switching

In a multiprotocol label switching (MPLS) domain, ATM label-switching routers (LSRs) are potentially capable of providing the highest forwarding capacity in the backbone network. Virtual circuit (VC) merging is a mechanism in an ATM-LSR that allows many IP routes to be mapped to the same VC label and provides a scalable mapping method that can support thousands of destinations. VC merging requires reassembly buffers so that cells belonging to different packets intended for the same destination do not interleave with each other. In this paper, the impact of VC merging on the buffering requirement for the reassembly buffers is investigated. We propose a realistic architecture that supports VC merging. We study the performance of this architecture using an analytic approach and using simulation driven by empirical Internet packet-size distribution. At the cell level, our main finding indicates that VC merging incurs a minimal overhead compared to non-VC merging, in terms of additional buffering. Moreover, the overhead decreases as utilization increases or as the traffic becomes more bursty with longer dependence. The finding has important practical consequences since routers and switches are dimensioned for high utilization and stressful traffic conditions. At the packet level, VC merging generally achieves a higher goodput than non-VC merging with EPD for the same buffer size. We also study the delay performance and find that the additional delay due to VC merging is insignificant at high speed