Antibacterial and anti-adhesive efficiency of Pediococcus acidilactici against foodborne biofilm producer Bacillus cereus attached on different food processing surfaces

Food Science and Biotechnology - This study aimed to assess the biofilm formation by Bacillus cereus on two novel surfaces namely: aluminum and cold steel in comparison study with stainless steel...     

Physico-mechanical and photoluminescence properties of EuxMg2−xSiO4 system sintered under different conditions

This work focuses on sintering of Eu_xMg_2?xSiO₄ (x = 0.0, 0.01, 0.03, 0.05) forsterite ceramics under different conditions and study their microstructures, physico-mechanical and photoluminescence characteristics. The starting materials were waste silica fume, pure MgO and europium oxide (Eu₂O₃). The prepared batches were sintered up to 1500 °C in the presence or absence of carbon in ambient atmosphere. The presence of carbon helped in reduction of Eu³⁺ into Eu²⁺. The effect of sintering conditions and formed phases on the properties of final product were investigated. The results indicated that the specimens sintered without carbon exhibited improved physico-mechanical properties with formation of forsterite and Eu_4.67 (SiO₄)₃O precipitated from the formed liquid phase. While the samples sintered in carbon exhibited lower physic-mechanical properties with formation of forsterite and clinoenstatite. Photoluminescence properties were improved with increasing the amount of added Eu₂O₃ for all sintered samples. The specimens sintered without carbon exhibited life time higher than those sintered in the presence of carbon.     

Multi-objective Genetic Topological Optimization for Design of Blast Resistant Composites

Composites make it possible to produce materials with properties that are unattainable with single phase materials. This paper examines the use of multi-objective genetic topological optimization to design blast resistant composites. The fundamental problem of the design of a two-layer composite plate that is subjected to blast is considered using the finite element method. Two materials are used to form the microstructure of each layer. The microstructure and thickness of each layer is optimized for the two-layer plate to minimize the weight and stress-to-strength ratio. A set of optimal blast resistant composite microstructures that meet design requirements is demonstrated.     

Cationic Polymer Modified Mesoporous Silica Nanoparticles for Targeted siRNA Delivery to HER2+ Breast Cancer

In vivo delivery of siRNAs designed to inhibit genes important in cancer and other diseases continues to be an important biomedical goal. A new nanoparticle construct that is engineered for efficient delivery of siRNA to tumors is now described. The construct comprises a 47‐nm mesoporous silica nanoparticle core coated with a crosslinked polyethyleneimine–polyethyleneglycol copolymer, carrying siRNA against the human epidermal growth factor receptor type 2 (HER2) oncogene, and coupled to the anti‐HER2 monoclonal antibody (trastuzumab). The construct is engineered to increase siRNA blood half‐life, enhance tumor‐specific cellular uptake, and maximize siRNA knockdown efficacy. The optimized anti‐HER2 nanoparticles produce apoptotic death in HER2 positive (HER2⁺) breast cancer cells grown in vitro, but not in HER2 negative (HER2^?) cells. One dose of the siHER2–nanoparticles reduces HER2 protein levels by 60% in trastuzumab‐resistant HCC1954 xenografts. Administration of multiple intravenous doses over 3 weeks significantly inhibits tumor growth (p < 0.004). The siHER2‐nanoparticles have an excellent safety profile in terms of blood compatibility and low cytokine induction, when exposed to human peripheral blood mononuclear cells. The construct can be produced with high batch‐to‐batch reproducibility and the production methods are suitable for large‐scale production. These results suggest that this siHER2‐nanoparticle is ready for clinical evaluation.     

Levels of Cu,Zn, Pb,and Cd in the leaves of the tea plant (Camellia sinensis) and in the soil of Gilan and Mazandaran farms of Iran

Tea is known as an inevitable and important part of a healthy and balanced diet. However, it might be contaminated by heavy metals via many ways, including irrigation by sewage water, industrial effluents, sewage sludge, vehicular emissions, industrial wastes, and atmospheric deposition. The concentrations of Cu, Zn, Cd, and Pb elements in the leaves and soil samples of the tea farms in North Iran were determined by using flame and graphite furnace atomic absorption spectrometry. The samples were digested with the concentrated nitric acid and perchloric acid. The descending sequence of the mean metal levels in the tea leaves is as follows: Zn > Cu > Pb > Cd. The content of heavy metals in the tea samples were found and are provided in the following ranges: 6.07–15.24, 55.35–127.22, 0.03–0.64, and 0.06–0.38 µg/g for Cu, Zn, Pb, and Cd, respectively. According to the Institute of Standards and Industrial Research of Iran (ISIRI), the tolerance limits have been adjusted only for copper, cadmium, and lead. However, the present database can be employed for fixing the tolerance limit of zinc in tea. The contents of copper and lead in tea were significantly lower than the permissible limit under the ISIRI act. In contrast, the cadmium concentration was significantly above the permissible limit (P < 0.05). In the conclusion, the comparisonis made between the research results and the literature values.     

Hydrogenolysis of sugar beet fiber by supported metal catalyst

Sugar beet fiber is an agricultural by-product in the sugar manufacturing and an available biomass source with a rich hemicellulose component. So far, there has been no report on the catalytic conversion of the beet fiber for the synthesis of chemicals. In this work, the hydrogenolysis of the beet fiber was studied by using supported metal catalysts under pressurized hydrogen conditions. Activated carbon supported Ru was found to show the highest catalytic activity to give arabitol as a major product in the hydrogenolysis of hemicellulose part of this material. The reuse ability of the catalyst was also investigated.     

Modeling particle shape-dependent dynamics in nanomedicine

One of the major challenges in nanomedicine is to improve nanoparticle cell selectivity and adhesion efficiency through designing functionalized nanoparticles of controlled sizes, shapes, and material compositions. Recent data on cylindrically shaped filomicelles are beginning to show that non-spherical particles remarkably improved the biological properties over spherical counterpart. Despite these exciting advances, non-spherical particles have not been widely used in nanomedicine applications due to the lack of fundamental understanding of shape effect on targeting efficiency. This paper intends to investigate the shape-dependent adhesion kinetics of non-spherical nanoparticles through computational modeling. The ligand-receptor binding kinetics is coupled with Brownian dynamics to study the dynamic delivery process of nanorods under various vascular flow conditions. The influences of nanoparticle shape, ligand density, and shear rate on adhesion probability are studied. Nanorods are observed to contact and adhere to the wall much easier than their spherical counterparts under the same configuration due to their tumbling motion. The binding probability of a nanorod under a shear rate of 8 s(-1) is found to be three times higher than that of a nanosphere with the same volume. The particle binding probability decreases with increased flow shear rate and channel height. The Brownian motion is found to largely enhance nanoparticle binding. Results from this study contribute to the fundamental understanding and knowledge on how particle shape affects the transport and targeting efficiency of nanocarriers, which will provide mechanistic insights on the design of shape-specific nanomedicine for targeted drug delivery applications.     

Characterization of composite materials based on LDPE loaded with agricultural tunisian waste

This study investigated the use of an available agricultural Tunisian vine stem waste as a filler material. Composites of green materials were prepared using vine stems as filler and low density polyethylene (LDPE) as a matrix. A series of composite films was prepared by different loadings of the vine stem waste with 10–50% of the filler in 10% intervals. The ensuing materials were characterized by several techniques. The morphology of the composites was investigated using scanning electron microscopy (SEM). The thermal and mechanical properties were studied using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), respectively. The results indicated that vine‐stem based particles enhanced the thermo‐mechanical properties of the thermoplastic matrix and demonstrated that this available lignocellulosic biomass of vine stems can be considered to be a promising filler material. However, the obtained result of water absorption indicated that the maximum limit of the filler content should not exceed 30% of vine stems. POLYM. COMPOS., 36:817–824, 2015. © 2014 Society of Plastics Engineers     

A microcomputer-based clinical trial database incorporated with an ‘audit trail’ for correction process

Multicenter clinical trials usually involve several hundred research variables with tens of thousands of records and require mainframe computers for processing. Because of recent advances in hardware and software, it has become possible to support data management and statistical analysis for a complex research project totally on a microcomputer. The Veterans Administration Cooperative Studies Program Coordinating Center (CSPCC) in Hines, IL, U.S.A. has successfully implemented three studies employing the SIR/PC Database Management System (DBMS) on an IBM PC AT. The CSPCC DBMS was designed with a method of verifying data and of updating the database, that leaves a more detailed ‘audit trail’ of the original data and subsequent modifications than provided by the SIR audit trail facility. Data validation can be done at any time throughout the study to facilitate error identification as early as possible in the data handling process. DBMS operation and maintenance are automated by a system of menus. The utility programs are prestored in a procedure file to optimize performance. The simple design speeds implementation and also reduces the cost of development.