Portable bead-based fluorescence detection system for multiplex nucleic acid testing: a case study with Bacillus anthracis

This paper describes the design, functioning and use of a portable detection platform for multiplex nucleic acid testing. The system features a bead-supported DNA hybridization assay performed inside a microfluidic cartridge. Polystyrene particles modified with DNA capture probes are confined in the detection area and exposed to a solution of fluorescently labeled target DNA strands. The cartridge, fabricated from inexpensive thermoplastic polymers, allows for conducting up to eight assays in parallel. The detection instrument is equipped with a pneumatic module and a manifold lid serving as an interface to mediate fluid displacement on the cartridge. The fluorescence signal deriving from each assay is recorded by a semi-confocal fluorescence reader embedded in the detection platform. The compact design of the instrument and its level of integration make it possible to obtain an analytical result in less than 15 min, while only few manual steps need to be performed in between. A proof-of-concept demonstration involving Cy3-labeled, PCR-amplified genomic DNA confirms the ability to detect Bacillus anthracis in a multiplexed single-assay format using lef and capC genes. Limits of quantification are on the order of 1 × 10⁹ copies/μL for lef targets.     

Information Security Risks in Enabling e-Government: The Impact of IT Vendors

The purpose of this article is to identify information systems security risks in local governments resulting from the cooperation with IT vendors. We focus on government-to-government projects where the confidentiality, integrity, and availability of information is a key concern. In our risk identification process, we take a systems thinking approach, taking into account actual and perceived risks. We identified 13 causes of risk in three risk areas and analyzed them using outsourcing literature.     

Comments on ‘‘a simple method for calculating detonation parameters of explosives'

Abstract

The present contribution deals with a modified method of estimating the detonation parameters starting with a general formulation of the adiabat for explosives as expressed using the adiabatic exponent γ_j = f(ρ₀) according to Wu Xiong¹. The author uses also the works of Russian authors.^2,7,8     

Content of anthocyanins and glycoalkaloids in blue‐fleshed potatoes and changes in the content of α‐solanine and α‐chaconine during manufacture of fried and dried products

In the last ten or so years, potatoes with purple or blue‐flesh and derivative products, for example chips, have appeared on the European markets. The interest in this raw material and these products is increasing among both producers and consumers searching for novel and attractive choices. The anthocyanin content of the analysed potato varieties differed; a higher content of these pigments was determined in Blaue Elise var. potatoes. In blue‐flesh varieties, the prevailing anthocyanins were acylated glycosides: petunidin and malvidin. The production process of French fries, chips and puree caused a decrease in the content of glycoalkaloids in semi‐products and finished products, compared to the raw material. The greatest losses of α‐chaconine and α‐solanine were observed after tuber peeling (ca. 70%) and after frying (ca. 90%). French fries contained 3%, chips 16% and puree 17% of the initial amount of total glycoalkaloids. The losses of α‐chaconine and α‐solanine in the analysed semi‐products and finished products were at the same level, regardless of the processing technology applied.     

Modelling of the Am(III) – Cm(III) kinetic separation effect observed during metal ion extraction by bis-(1,2,4)-triazine ligands

The kinetic separation effect was observed leading to a separation factor for Am(III) over Cm(III) as high as 7.9 by using 2,9-bis-(1,2,4-triazin-3-yl)-1,10-phenantroline (BTPhen) ligands in our recent study. In an attempt to explain the observed tendencies, several kinetic models were tested. A model based on mass transfer as the rate-controlling process was found to best describe the kinetic data and allowed to simulate the dependence of Am/Cm separation factor on time. The calculated values of the overall mass-transfer coefficients confirmed that the observed kinetic effect was caused by the different rates of Am(III) and Cm(III) extraction. This kinetic separation phenomenon and its explanation paves the way for potential new approaches to separation of metal ions with very similar properties, such as the adjacent minor actinides Am(III) and Cm(III).     

Number and size of lupulin glands,glandular trichomes of hop (Humulus lupulus L.), play a key role in contents of bitter acids and polyphenols in hop cone

Hop (Humulus lupulus L.) inflorescence, commonly known as ‘hop cone’, is valuable for contents of bitter acids, essential oils and polyphenols, used in brewing industry and biomedical application. These compounds are predominantly formed in glandular trichomes, known as ‘lupulin glands’. In this study, we investigated chemical and morphological characteristics of lupulin glands by microscopy and HPLC analyses. Even though no significant correlations were found between lupulin glands and hop cones for contents of alpha and beta bitter acids, polyphenols, all ratios between individual metabolites (alpha/beta acids, X/alpha acids, X/DMX) were highly and significantly correlated. The average number of lupulin glands on bract/bracteole ranged from 115 to 713 with 28.5% of variability. Linear regression analyses confirmed that total volume of lupulin glands and total lupulin glands area on bract/bracteole surface highly correlated with contents of bitter acids and polyphenols in hop cone. Therefore, lupulin glands are unique and exclusive organs responsible for contents of bitter acids and polyphenols in hop cone.     

THERMAL DEHYDRATION OF THE SODIUM CARBONATE HYDRATES

A thermal gravimetric method was employed to explore the course of dehydration of Na₂CO₃ · 10 H₂O, and Na₃CO₃ · H₂O particles. Experimental data were amassed both in the temperature-increasing and constant temperature mode. Very small sample masses were used in an effort to eliminate an effect of heat and mass transfer processes on the rate of reaction. Kinetic equations of Arrhenius type were proposed for two stages of the dehydration and tested against the results collected by experiment.     

Risk managements' communicative effects influencing IT project success

The central question of this research is if, and how, risk management contributes to the success of IS/IT projects. Risk management is used regularly in IT projects, despite indications in literature that risk management only occasionally contributes to IT project success. Drawing on Habermas we distinguish between instrumental and communicative effects of risk management. Stakeholders from seven ERP implementation projects indicate that in addition to the instrumental effects of risk management, being direct risk mitigating actions by stakeholders, individual risk management activities are able to generate communicative effects. Communicative effects create a commonly shared definition of the situation by influencing stakeholders' perceptions and expectations and by defining the inter-stakeholder project relations. These effects contribute to the effectiveness of instrumental action, and consequently to project success. Stakeholders consider risk identification to be the most influential risk management activity, both in number and in strength of the effects.     

The influence of ECAP on the small punch creep of Al–4 vol.% Al<Subscript>4</Subscript>C<Subscript>3</Subscript> composite

The creep behaviour of a composite based on an aluminium matrix reinforced by 4 vol.% Al₄C₃ was studied at temperatures of 623 and 723 K by small punch testing with a constant force. The composite was tested in two different states: (i) as received by mechanical alloying with hot extrusion (HE) as the final operation and (ii) with equal channel angular pressing (ECAP) superimposed on the hot-extruded material. The ECAP does not improve the observed creep resistance. The reduction of force leading to the same deflection rate is not very significant. This points out that the ECAP process of the present composite, which produces substantial strengthening at lower temperatures, is not accompanied by pronounced weakening of creep resistance at elevated temperatures. The threshold force in the ECAP material is about 5 N weaker than in the HE material.