Synthesis and Characterization of Cubic Omega-3-coated Cobalt Ferrite Nanoparticles

This research focuses on the synthesis and characterization of novel nanocomposite containing CoFe₂O₄ nanoparticles coated with omega-3. The omega-3 shell is a completely biocompatible. In this paper, cubic magnetic nanoparticles were synthesized by a simple one-step wet chemical method at room temperature. The product was characterized using standard techniques: X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and vibrating sample magnetometry (VSM). The results obtained from FTIR and TGA indicate that omega-3 was adsorbed onto the surface of the magnetic nanoparticles. With respect to the heat generation mechanisms such as relaxation and hysteresis, cobalt ferrite single-domain nanoparticles exhibit much larger specific power losses than superparamagnetic particles due to the high anisotropy constant. The synthesized nanocomposite has a saturation magnetization and a coercive field about 31.5 Am² kg^?1 and 1.2 × 10⁵ A m^?1, respectively. The coercivity of as-prepared nanocomposites is higher than that reported in previous works, so they are suitable for the aforementioned heat generation mechanism.     

Application of shellac for the development of probiotic formulations

In this study, we have improved the enteric properties of shellac and developed probiotic formulations comprising this natural polymer. The effects of plasticizers such as glycerol and glyceryl triacetate, as well as water-soluble polymers such as sodium alginate, hydroxypropyl methylcellulose and polyvinylpyrrolidone on thermodynamic characteristics and coating properties of shellac were evaluated. The data indicate that glycerol showed the best plasticization effect. Hydroxypropyl methylcellulose and polyvinylpyrrolidone had superior miscibility with shellac compared to sodium alginate. Then, three fluid-bed dried bacterial species i.e., Enterococcus faecium, Bifidobacterium bifidum and Lactobacillus reuteri, were coated with formulations comprising different concentrations of shellac and additives. Coatings with shellac containing 5% glycerol or 5% sodium alginate or up to 20% [w/w] polyvinylpyrrolidone protected the microorganisms against acidic pH and provided the best release profile in simulated intestinal fluid. Moreover, these formulations maintained promising cell survival rates after four months of storage at 5 °C. E. faecium and B. bifidum showed more resistance to manufacturing process than L. reuteri.     

Growth and survival of Lactobacillus reuteri RC-14 and Lactobacillus rhamnosus GR-1 in yogurt for use as a functional food

Both Lactobacillus reuteri RC-14 and Lactobacillus rhamnosus GR-1 are considered probiotic agents with therapeutic properties. To prepare mother cultures for these organism bacteria, four formulations were made with milk (1% fat) with 0.33% yeast extract (T1); 0.4% inulin (T2); 0.33% yeast extract and 0.4% inulin (T3); and one with no additives (T4). The media were inoculated with 1% probiotic cultures and incubated anaerobically at 37 °C overnight. Low-fat (1%) probiotic yogurts were made. Survival of L. reuteri RC-14 and L. rhamnosus GR-1 was monitored after 1, 7, 14, 21, and 28 days of storage at 4 °C. In all treatments, L. rhamnosus GR-1 survived significantly better (P < 0.05) than L. reuteri RC-14. Survival was highest in media T1 and T3. This study shows that yogurt has the potential to deliver probiotic bacteria to consumers, with L. rhamnosus GR-1 providing excellent shelf life.Industrial relevanceThis study is of relevance to food industry because it deals with the effectiveness of dairy products as a good-vehicle for delivering probiotic microorganisms to consumers. The fermentation of milk into yogurt has gained widespread consumer acceptance in North America and its consumption has increased significantly over the past few years. The normal yogurt cultures, Lactobacillus delbreukii sub-species bulgaricus and Streptococcus thermophilus, are not bile resistant or acid tolerant and thus cannot survive in the intestinal tract, although they may help to lessen the symptoms of lactose intolerance. Various strains of lactic acid bacteria are considered probiotics. Two of the most documented probiotic strains, Lactobacillus reuteri (formerly fermentum) RC-14 and Lactobacillus rhamnosus GR-1 can colonize the intestine and vagina and reduce recurrences of bacterial vaginosis, yeast vaginitis and urinary tract infections. They are bile resistant and survive passage through the human gastrointestinal tract without induction of systemic immune or inflammatory responses. There is no published information on the growth and survival of L. rhamnosus GR-1 and L. reuteri RC-14 in yogurt. The incorporation of L. rhamnosus GR-1 and L. reuteri RC-14 in yogurt is an innovative idea. This research developed a new probiotic yogurt with sufficient viable counts of L. rhamnosus GR-1 accompanied by L. reuteri RC-14. The use of probiotic bacteria, especially those with proven therapeutic effects, in dairy products has attracted a lot of attention from dairy industry and health/wellness industry, and this type of product can provide a bridge between the two industries.     

A model to control environmental performance of project execution process based on greenhouse gas emissions using earned value management

In response to recent climate change, which is believed to be attributed to the release of greenhouse gas (GHG) emissions, many countries are placing CO2 abatement programs such as carbon tax and cap-and-trade. Projects do have a significant share in GHGs and therefore their environmental performance, like their schedule and cost performance, should be monitored and controlled. Although many large projects would pass an environmental assessment in the project evaluation phase, the issue of environmental performance monitoring during the project execution phase has not been addressed in project management methodologies. The objective of this paper is to develop a model to estimate project GHG emissions, and to measure project GHG performance using the developed metrics, which can be used at any point in time over the life of a project. A comprehensive study is conducted to collect information on GHG emission factors of various project activity data (such as material use, energy and fuel consumption, transportation, etc.), and a user form interface is developed to calculate the total GHG of an activity. Also, a breakdown structure is proposed which supports managing all the project GHG accounts. The monitoring and control model is formulated based on the logic used in earned value management (EVM) methodology. The proposed model is then implemented to a work package of a real construction project. The results present the project initial GHG plan and show that the model is able to calculate project GHG variance by the reporting date and predict project final GHG based on a project GHG performance index. The method presented in this paper is general and can be applied to any type of projects in an organization that aims to reduce its carbon footprint. The same structure can be applied to monitor and control any other environmental impact associated with project execution process.     

Effect of lyoprotectants on β-glucosidase activity and viability of Bifidobacterium infantis after freeze-drying and storage in milk and low pH juices

The benefit of disaccharide protectants for maintaining viability and β-glucosidase activity of Bifidobacterium infantis UV16PR during freeze-drying and storage in different food matrices was investigated. Protectants used were cellobiose, lactose, sucrose and trehalose.     

Reliability analysis of maintenance data for complex medical devices

This paper proposes a method to analyze statistically maintenance data for complex medical devices with censoring and missing information. It presents a classification of the different types of failures and establishes policies for analyzing data at the system and component levels taking into account the failure types. The results of this analysis can be used as basic assumptions in the development of a maintenance/inspection optimization model. As a case study, we present the reliability analysis of a general infusion pump from a hospital. Copyright © 2010 John Wiley & Sons, Ltd.     

Trend analysis of the power law process using Expectation-Maximization algorithm for data censored by inspection intervals

Trend analysis is a common statistical method used to investigate the operation and changes of a repairable system over time. This method takes historical failure data of a system or a group of similar systems and determines whether the recurrent failures exhibit an increasing or decreasing trend. Most trend analysis methods proposed in the literature assume that the failure times are known, so the failure data is statistically complete; however, in many situations, such as hidden failures, failure times are subject to censoring. In this paper we assume that the failure process of a group of similar independent repairable units follows a non-homogenous Poisson process with a power law intensity function. Moreover, the failure data are subject to left, interval and right censoring. The paper proposes using the likelihood ratio test to check for trends in the failure data. It uses the Expectation-Maximization (EM) algorithm to find the parameters, which maximize the data likelihood in the case of null and alternative hypotheses. A recursive procedure is used to solve the main technical problem of calculating the expected values in the Expectation step. The proposed method is applied to a hospital's maintenance data for trend analysis of the components of a general infusion pump.     

Isolating recombinant antibodies against specific protein morphologies using atomic force microscopy and phage display technologies

Isolation of antibodies to antigens that are either unstable, exist in multiple morphologies or have very limited availability can be prohibitively difficult. Here we describe a novel technique combining the capabilities of phage display antibody technology and atomic force microscopy (AFM) that is used to isolate antibody fragments that bind to a specific morphology of the target antigen, alpha-synuclein. AFM imaging allows us to both visualize the presence and morphology of the target antigen as well as to monitor the efficiency of each step in the bio-panning process. We demonstrate that phage displayed antibodies specific to the target antigen morphology can be isolated after only two rounds of selection. The target antigen, alpha-synuclein, has been correlated with the Parkinson's disease (PD). Accumulation of alpha-synuclein fibrillar aggregates into Lewy body inclusions is a hallmark feature of PD. While alpha-synuclein can form several different aggregate morphologies including oligomers, protofibrils and fibrils, the role of these morphologies in the progression of PD is not known. The successful selection of the recombinant antibody described here can have potential therapeutic value since the single-chain fragment variable (scFv) can be expressed intracellularly to control folding and toxicity of the specific protein aggregates.     

Pd nanoparticle loaded TiO<Subscript>2</Subscript> semiconductor for photocatalytic degradation of Paraoxon pesticide under visible-light irradiation

Overuse of the organophosphorus pesticides such as Paraoxon in agriculture industry has raised significant threats to the environment by contamination of soils and groundwaters. Therefore, extensive studies have been carried out to develop an effective method for removing of these poisonous pollutants from contaminated resources. In the current study, Pd nanoparticle loaded TiO₂ nanocomposites with different weight percentages of Pd were prepared via a facile photoreduction method and for the first time, were used for photocatalytic degradation of Paraoxon under visible-light irradiation. The prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy techniques. In these nanocomposites, the presence of Pd nanoparticles enhances the photocatalytic activity of TiO₂ by their surface plasmon resonance effect and also by narrowing the band gap energy of TiO₂. The results of photocatalytic activity measurements indicate that the nanocomposite with 0.8 wt% content of Pd (PT0.8) has the best photocatalytic activity. The result of total organic carbon test shows that Paraoxon was completely mineralized by PT0.8 photocatalyst after 120 min, under visible-light irradiation.