Study on crosslinked gelatin–montmorillonite nanoparticles for controlled drug delivery applications

Gelatin, because of its biodegradability and ecofriendly nature, has been the best choice for controlled release applications. Montmorillonite (MMT) clay shows a very important role in controlling drug delivery. Hence, an attempt was made in this work to prepare gelatin–MMT nanoparticles by desolvation method using acetone as precipitating agent, glutaraldehyde (GA) as crosslinking agent, and water as reaction media for controlled delivery of isoniazid, a drug for tuberculosis. Characterization of the MMT and isoniazid-loaded gelatin–MMT nanoparticles was carried out using Fourier transform infrared spectroscopy, X-ray diffraction study, scanning electron microscopy study, and transmission electron microscopy study. The effect of MMT on gelatin nanoparticles was evaluated in terms of water uptake studies, and subsequently to the release of isoniazid drug in buffer solution at pH 1.2 (gastric pH) and pH 7.4 (intestinal pH). Swelling experiment indicated that the gelatin nanoparticles were very sensitive to the pH environment. The release profile of drug was studied by a UV–Visible spectrophotometer. Cytotoxicity study revealed that MMT-containing nanoparticles showed less cytotoxicity than MMT-free nanoparticles.     

Incremental learning framework for real‐world fraud detection environment

For detecting malicious bidding activities in e‐auctions, this study develops a chunk‐based incremental learning framework that can operate in real‐world auction settings. The self‐adaptive framework first classifies incoming bidder chunks to counter fraud in each auction and take necessary actions. The fraud classifier is then adjusted with confident bidders' labels validated via bidder verification and one‐class classification. Based on real fraud data produced from commercial auctions, we conduct an extensive experimental study wherein the classifier is adapted incrementally using only relevant bidding data while evaluating the subsequent adjusted models' detection and misclassification rates. We also compare our classifier with static learning and learning without data relevancy.     

High-efficiency resonant coupled wireless power transfer via tunable impedance matching

For magnetic resonant coupled wireless power transfer (WPT), the axial movement of near-field coupled coils adversely degrades the power transfer efficiency (PTE) of the system and often creates sub-resonance. This paper presents a tunable impedance matching technique based on optimum coupling tuning to enhance the efficiency of resonant coupled WPT system. The optimum power transfer model is analysed from equivalent circuit model via reflected load principle, and the adequate matching are achieved through the optimum tuning of coupling coefficients at both the transmitting and receiving end of the system. Both simulations and experiments are performed to evaluate the theoretical model of the proposed matching technique, and results in a PTE over 80% at close coil proximity without shifting the original resonant frequency. Compared to the fixed coupled WPT, the extracted efficiency shows 15.1% and 19.9% improvements at the centre-to-centre misalignment of 10 and 70 cm, respectively. Applying this technique, the extracted S₂₁ parameter shows more than 10 dB improvements at both strong and weak couplings. Through the developed model, the optimum coupling tuning also significantly improves the performance over matching techniques using frequency tracking and tunable matching circuits.     

Comparison of crashes during public holidays and regular weekends

Traffic collisions and fatalities during the holiday festive periods are apparently on the rise in Alberta, Canada, despite the enhanced enforcement and publicity campaigns conducted during these periods. Using data from 2004 to 2008, this research identifies the factors that delineate between crashes that occur during public holidays and those occurring during normal weekends. We find that fatal and injury crashes are over-represented during holidays. Amongst the three risky behaviors targeted in the holiday blitzes (driver intoxication, unsafe speeding and restraint use), non-use of restraint is more prevalent whereas driver intoxication and unsafe speeding are less prevalent during holidays. The mixed results obtained suggest that it may be time to consider a more balanced approach to the enhanced enforcement and publicity campaigns.     

Isolation and molecular identification of Cronobacter spp. from powdered infant formula (PIF) in Bangladesh

Cronobacter spp. formerly known as Enterobacter sakazakii is an occasional contaminant of powdered infant formula (PIF). This pathogen has been associated with out-breaks of a rare form of infant meningitis, necrotizing enterocolitis (NEC), bacteremia and neonate deaths. The organism is ranked by the International Commission for Microbiological Specifications for Foods (ICMSF) as a ‘Severe hazard for restricted populations, life threatening or substantial chronic sequelae or long duration’. Present study aimed to isolate Cronobacter spp. from PIF and clinical samples, such as blood, stool and CSF collected from 93 neonates and child patients, age ranged from 0 to 24 months. We did not detect Cronobacter spp. in any of these samples. Later 32 PIF samples collected from retail markets in Bangladesh were tested for the presence of Cronobacter spp. Of these only one was found to be contaminated with Cronobacter sp. This is the first case of Cronobacter contaminated PIF found in Bangladesh to be reported. The organism was successfully identified based on its typical culture characteristics, producing blue-green colonies on chromogenic DFI agar and also by a standardized conventional PCR assay targeting the alpha glucosidase and 16 S rRNA gene sequence of Cronobacter sp. The 16 S rRNA gene was partially sequenced to provide for the phylogenetic analysis of this isolate (DA01) and found to cluster with some other Cronobacter isolates in the phylogram.     

Cooperative vehicle positioning with multi-sensor data fusion and vehicular communications

Wireless Networks - Vehicular positioning with multi-sensor fusion has achieved promising results in recent years. Having potential benefit from the emerging vehicular communications based on IEEE...     

Comparative study of survival of altered and hybrid Vibrio cholerae O1 El Tor in association with Anabaena variabilis in fresh and brackish water microcosms

The survival of altered and hybrid Vibrio cholerae O1 El Tor in association with a cyanobacterium, Anabaena variabilis in pond (fresh) and brackish water microcosms was investigated. Survival of culturable bacteria was monitored on taurocholate tellurite gelatine agar plate. Viable but nonculturable (VBNC) bacteria were examined using fluorescent antibody (FA) technique. In pond water, altered and hybrid El Tor survived with cyanobacteria 10 and 18 days respectively and in control water 6 and 12 days respectively in culturable state. In pond water VBNC state altered and hybrid El Tor were found to persist 48 and 53 days respectively but in brackish water 65 and 70 days respectively in association with cyanobacteria. Brackish water was found to be a better habitat than pond water for the survival of these strains. Hybrid El Tor survived longer inside the mucilaginous sheath of A. variabilis than altered El Tor both in pond and brackish water microcosms.     

A study on the manufacturing conditions of metal matrix composites by low pressure infiltration process

Metal fiber preform reinforced aluminum alloy composite as made by the infiltration of molten metal under low pressure casting process. The infiltration behavior of filling pattern and the velocity profile with low-pressure casting process was investigated. The thermocouple was inserted into the preform in order to observe the infiltration behavior. The infiltration of applied pressure time, 1, 2 and 5 s under constant pressure of 0.4 MPa was completely filled during 0.4 s. In these conditions, molten aluminum alloy has successfully infiltrated to FeCrSi metal fiber preform by low-pressure casting process. It was observed the porosity of composites for reliability of composites. The automobile piston was developed with FeCrSi reinforced aluminum alloy that is 0% porosity by the optimal applied pressure and applied pressure time.