Evaluation of applied biosystems MicroSeq real-time PCR system for detection of Listeria monocytogenes in food. Performance Tested Method 011002

Increasingly, more food companies are relying on molecular methods, such as PCR, for pathogen detection due to their improved simplicity, sensitivity, and rapid time to results. This report describes the validation of a new Real-Time PCR method to detect Listeria monocytogenes in nine different food matrixes. The complete system consists of the MicroSEQ L. monocytogenes Detection Kit, sample preparation, the Applied Biosystems 7500 Fast Real-Time PCR instrument, and RapidFinder Express software. Two sample preparation methods were validated: the PrepSEQ Nucleic Acid extraction kit and the PrepSEQ Rapid Spin sample preparation kit. The test method was compared to the ISO 11290-1 reference method using an unpaired-study design to detect L. monocytogenes in roast beef, cured bacon, lox (smoked salmon), lettuce, whole cow's milk, dry infant formula, ice cream, salad dressing, and mayonnaise. The MicroSEQ L. monocytogenes Detection Kit and the ISO 11290-1 reference method showed equivalent detection based on Chi-square analysis for all food matrixes when the samples were prepared using either of the two sample preparation methods. An independent validation confirmed these findings on smoked salmon and whole cow's milk. The MicroSEQ kit detected all 50 L. monocytogenes strains tested, and none of the 30 nontargeted bacteria strains.     

Dynamic correlation effects on drag resistivity of a symmetric electron–electron bilayer

We have studied the effect of dynamic electron correlations on Coulomb drag in a low density symmetric electron–electron bilayer. The drag resistivity is calculated considering the contribution from direct e–e scattering processes using the semi-classical Boltzmann approach, with the effective inter-layer interaction W₁₂(q, ω; T) determined within the ?wierkowski, Szyman?ki, and Gortel model, generalized to include the dynamics of electron correlations through the frequency-dependent intra- and inter-layer local-field correction (LFC) factors. In turn, the LFCs are obtained by extending the quantum Singwi, Tosi, Land, and Sjölander (qSTLS) approach to finite temperatures. At low temperatures (T ? 2 K), the calculated drag resistivity is found to agree nicely with the measurements by Kellogg et al., while it is somewhat overestimated at higher temperatures. The overestimation is seen to increase with decreasing density of electrons. However, there is found to be a marked improvement over the predictions of the conventional (i.e., static) STLS and random-phase approximation (RPA). It turns out that the inclusion of exchange-correlations in the RPA causes a red-shift in the bilayer plasmons which leads to an enhancement of drag resistivity. Our study demonstrates clearly the importance of including the dynamical nature of correlations to have a reasonable account of measured drag resistivity.     

Study of biopolymer I-carrageenan with magnesium perchlorate

The green revolution has led to the study of biopolymer for development of polymer electrolyte for electrochemical devices. Cellulose acetate, pectin, chitosan, and carrageenan are some of the biopolymers. Biopolymer-based membrane for proton conduction and lithium ion conduction have developed and characterized by different techniques. But the study of biopolymer based on Mg²⁺ ion is rare in literature. So, biopolymer based on I-carrageenan with magnesium has been studied. I-carrageenan biopolymer membrane with different concentration of magnesium perchlorate has been prepared by solution casting technique. Developed biopolymer membrane have been characterized by X-ray diffraction analysis (XRD), FTIR, differential scanning calorimetry (DSC), and AC impedance techniques. Pure I-carrageenan has shown a conductivity value of 5.90?×?10^?5 S/cm. I-carrageenan membrane with 0.6 wt% of magnesium perchlorate has shown a conductivity of 2.18?×?10^?3 S/cm. A primary Mg²⁺ ion battery has been constructed and its performance is studied. XRD has been undertaken to study the amorphous/crystalline nature of the sample. I-carrageenan with 0.6 wt% of magnesium membrane has shown highest amorphous nature. FTIR study confirms the complex formation between polymer and salt. AC impedance technique has been used to study the conductivity of the samples.     

Development of 1-(4-(Substituted)piperazin-1-yl)-2-((2-((4-methoxybenzyl)thio)pyrimidin-4-yl)oxy)ethanones That Target Poly (ADP-Ribose) Polymerase in Human Breast Cancer Cells

A number of uracil amides cleave poly (ADP-ribose) polymerase and therefore novel thiouracil amide compounds were synthesized and screened for the loss of cell viability in a human-estrogen-receptor-positive breast cancer cell line. The synthesized compounds exhibited moderate to significant efficacy against human breast cancer cells, where the compound 5e IC₅₀ value was found to be 18 μM. Thouracil amide compounds 5a and 5e inhibited the catalytical activity of PARP1, enhanced cleavage of PARP1, enhanced phosphorylation of H2AX, and increased CASPASE 3/7 activity. Finally, in silico analysis demonstrated that compound 5e interacted with PARP1. Hence, specific thiouracil amides may serve as new drug-seeds for the development of PARP inhibitors for use in oncology.     

Synthesis of 1D β-MnO2 for high-performance supercapacitor application

Journal of Solid State Electrochemistry - Electrochemical supercapacitors (ESs) still need to overcome development obstacles in order to realize their full potential while being acknowledged as a...     

Computational and experimental investigations on the effect of crystallinity and crystal size on Na-transport in nanoscaled Si: implications for Si-based anodes for Na-ion batteries

Journal of Solid State Electrochemistry - While Li transport in Si is well understood, little is known about Na transport, despite Si being considered a potential anode material for the upcoming...     

ChemInform Abstract: Synthesis of Novel Zerumbone Derivatives via Regioselective Palladium Catalyzed Decarboxylative Coupling Reaction: A New Class of α‐Glucosidase Inhibitors.

A strategy for the synthesis of novel zerumbone derivatives via a regioselective palladium catalyzed decarboxylative coupling reaction using arene carboxylic acids is described.     

Growth and characterization of pure and Hg2+ doped thiosemicarbazide cadmium chloride crystals

Semiorganic single crystals of thiosemicarbazide cadmium chloride (TSCCC) and mercury ions doped thiosemicarbazide cadmium chloride were synthesized by slow solvent evaporation technique. The grown crystals were subjected to powder X‐ray analysis and both the crystals were found to crystallize in the monoclinic system. EDAX analysis was carried out for chemical analysis of the grown crystals. The UV‐Vis‐NIR spectrum shows that both the materials have wide transparency window in the visible and near IR region. The dielectric studies were carried out to estimate the dielectric constant and dielectric loss with respect to frequency for both the crystals. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)