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.     

2‐Aminothiazoles with Improved Pharmacotherapeutic Properties for Treatment of Prion Disease

Recently, we described the aminothiazole lead (4‐biphenyl‐4‐ylthiazol‐2‐yl)‐(6‐methylpyridin‐2‐yl)‐amine ( 1 ), which exhibits many desirable properties, including excellent stability in liver microsomes, oral bioavailability of ～40 %, and high exposure in the brains of mice. Despite its good pharmacokinetic properties, compound 1 exhibited only modest potency in mouse neuroblastoma cells overexpressing the disease‐causing prion protein PrP^Sc. Accordingly, we sought to identify analogues of 1 with improved antiprion potency in ScN2a‐cl3 cells while retaining similar or superior properties. Herein we report the discovery of improved lead compounds such as (6‐methylpyridin‐2‐yl)‐[4‐(4‐pyridin‐3‐yl‐phenyl)thiazol‐2‐yl]amine and cyclopropanecarboxylic acid (4‐biphenylthiazol‐2‐yl)amide, which exhibit brain exposure/EC₅₀ ratios at least tenfold greater than that of compound 1 .     

Light core and intelligent edge for a flexible, thin-layered, and cost-effective optical transport network

We present a new optics-based transport architecture that emulates fast switching in the network core via emerging fast tunable lasers at the network edge, and bypasses the need for fast optical switching and buffering. The new architecture is capable of handling both asynchronous and synchronous traffic, for dealing with various bandwidth granularities and responding to dynamic changes in end-to-end traffic demands. The architecture also reduces the amount of layering in the transport network by eliminating packet and TDM switching, keeps the network core light (lightweight and transparent), and pushes intelligence to the network edge. We discuss technical challenges that arise in the new architecture and describe possible approaches to address them.     

Determinants of serum leptin levels in Cushing's syndrome

Corticosteroids and insulin increase leptin expression in vivo and in vitro. To investigate whether increased serum cortisol influences serum leptin concentrations in humans, we analyzed fasting serum leptin and insulin levels in 50 patients with Cushing's syndrome [34 female patients: 27 with the pituitary form and 7 with the adrenal form; age, 41.6 +/- 2.7 yr; body mass index (BMI), 29.6 +/- 1.2 kg/m2; 16 male patients all with the pituitary form; age, 39.2 +/- 3.1 yr; BMI, 26.3 +/- 2.3 kg/m2] and in controls matched for BMI, age, and gender. Serum leptin levels were higher in female than in male patients in both the Cushing (P < 0.01) and control (P < 0.001) groups. Disease-specific differences in serum leptin levels were only detected in male (106 vs. 67 pmol/L; Cushing's syndrome vs. control, P < 0.05), not female, patients. Multiple stepwise regression analysis of both patient groups revealed insulin as the best predictor of serum leptin concentrations, accounting for 37% of the variance in serum leptin levels, in contrast to BMI or mean serum cortisol (as measured by sampling in 10-min intervals over 24 h). In the subgroup of patients (n = 9) with pituitary adenoma, serum leptin levels were reduced after tumor resection, with concurrent decreases in serum cortisol, insulin, and BMI. In conclusion, chronic hypercortisolemia in Cushing's syndrome appears not to directly affect serum leptin concentrations, but to have an indirect effect via the associated hyperinsulinemia and/or impaired insulin sensitivity.