Gas Identification by Simultaneous Permeation through Parallel Membranes: Proof of Concept.

This paper describes an experimental system for simultaneous permeation of a pressurized test gas through different gas permeable membranes and provides a proof of concept for a novel approach for gas identification/fingerprinting for potential construction of electronic noses. The design, construction, and use of a six-channel system which allows simultaneous gas permeation from a single pressurized gas compartment through six different parallel membranes are presented. The permeated gas is accumulated in confined spaces behind the respective membranes.

An Online Management System for Streamlining and Enhancing the Quality of Learning Outcomes Assessment.

Learning outcomes assessment is an effective academic quality assurance tool that enables educators to review and enhance the alignment between planned, delivered, and experienced curricula. Accurately assessing what students know and are able to do after completing a learning module is the first step to decide on the strategies to implement and the proper actions to take in order to ensure the continuous improvement of the student learning experience. Nonetheless, learning outcomes assessment processes in higher education are still facing major challenges that affect their proper and effective implementation.

Vitamin D Is Necessary for Murine Gastric Epithelial Homeostasis.

Unlike other organs, the importance of VD in a normal stomach is unknown. This study focuses on understanding the physiological role of vitamin D in gastric epithelial homeostasis. C57BL/6J mice were divided into three groups that were either fed a standard diet and kept in normal light/dark cycles (SDL), fed a standard diet but kept in the dark (SDD) or fed a vitamin D-deficient diet and kept in the dark (VDD).

Selective potentiometric determination of nitrite ion using a novel (4-sulphophenylazo-)1-naphthylamine membrane sensor.

A novel polymeric membrane sensor sensitive to (4-sulphophenylazo-)1-naphthylamine (SPAN) based on the use of tris(bathophenanthroline) Ni(II)-SPAN ion pair as an ion exchanger in plasticised PVC membrane is described. The sensor exhibits a linear calibration plot with near-Nernstian anionic slope of -55.0+/-0.

Prototype amperometric biosensor for sialic acid determination.

This paper describes the first report on the development, characterization, and applications of a prototype amperometric biosensor for free sialic acid (SA). The sensor was constructed by the coimmobilization of two enzymes, i.e.

Serum fluoride levels in a group of Egyptian infants and children from Cairo city.

In this study, the authors investigated fluoride levels in the serum of infants and children (n = 296) and in the breast milk from nursing mothers (n = 60) in Cairo city. Their goal was to evaluate the necessity and safety of implementing a fluoride supplementation program. The authors used an ion-selective electrode to assay fluoride by direct potentiometry.

A novel 1,10-phenanthroline-sensitive membrane sensor for potentiometric determination of Hg(II) and Cu(II) cations.

Preparation, characterization, and applications of a 1,10-phenanthrolinium cation (phenH(+))-sensitive potentiometric sensor are described. The sensor incorporates a liquid polymeric membrane consisting of phenH-tetraphenylborate, nitrophenyloctyl ether, and poly(vinyl chloride) as ion exchanger, plasticizer, and polymeric support, respectively. The sensor exhibits a fast and Nernstian response to phenH(+) over the concentration range of 6 x 10(-6)-2 x 10(-4) M with a monovalent cationic slope of 58.

Improved electrodeposited iridium oxide pH sensor fabricated on etched titanium substrates.

In the present paper, the preparation and characterization of an improved solid-state pH sensor are described. The sensor is based on anodically electrodeposited iridium oxide film, as a pH-sensing layer. Merits of the present sensor include (i) excellent adhesion of the pH sensitive layer to the substrate, (ii) excellent reproducibility of sensor fabrication, (iii) faster preparation procedure, and (iv) low cost of the titanium substrate.

Measurement of extracellular pH, K(+), and lactate in ischemic heart.

Simultaneous and continuous measurements of extracellular pH, potassium (K(+)), and lactate (L(-)) in ischemic rabbit papillary muscle are presented for the first time. Potentiometric pH and K(+) sensors and an amperometric lactate biosensor were used. These miniature electrodes were previously developed and individually tested for this purpose.