Visual Layout of Print Questionnaires: Effect on Responses of Middle School Students

A three-page questionnaire was modified to a one-page format. Questionnaires were administered in classroom groups to 300 middle school students. Classrooms were randomly divided into two groups, with one group receiving the original three-page format and the other receiving a single-page version of the same questionnaire. The visual layout of the two versions was different, and included variations in font, placement of response options, and spacing. Item non-response was greater for the single-page format. No statistically significant differences were detected between response patterns or internal consistency of the two versions of the questionnaire. Implications for school counselors are discussed

Versatile continuous pH monitoring barcode system based in ionogels

The online monitoring of pH level in different environments like bio-engineering [1] and chemistry [2] is vital for the control and well behaviour of the whole industrial process. Still exist the demand of miniaturised, versatile and autonomous systems which do not require of sensor calibration, replacement and manual attention over a long operational interval. In this abstract we present an innovative miniaturisable system for continuously measurement of pH solutions and vapours streams during chemical or biological processes. It consists on a simple barcode sensor with several pH dyes doped in an ionogel matrix. This ionogel is a hybrid material fabricated from an hydrogel polymer (N-isopropylacrylamide and N,N-methylene-bis(acrylamide) ratio 100:5) and an ionic liquid (Trihexyltetradecylphosphonium dicyanoamide). The barcode sensor consists of nineteen independent micro-wells (120 mm by 50 m) fabricated in poly(methyl methacrylate) and pressure-sensitive adhesive in three layers using a CO2 ablation laser. Different optically responsive molecular recognition ligands (pH-dyes) were incorporated in the ionogel matrix during monomers photo-polymerisation within each of the micro-wells generating a pH-sensor array for specific sensing applications like colorimetric, environmental or chemical sensing, Figure 1. It was observed that no leaching of pH dyes occurred during experiments and that the ionogel material was impressively robust under harsh conditions (pH:1 to pH: 14). The result is a sensing barcode which is able to generate a characteristic fingerprint-type colour of response within a single “snapshot” for different pH solutions and vapours. Moreover the pH response can be monitoring continuously and the barcode is reusable at least fifty times without sensitivity withdrawing

A PILOT STUDY OF PLANS THAT THE UNITED STATES FOOD INDUSTRY HAS FOR PARTICIPATING IN EASTERN EUROPE

Agribusiness, International Relations/Trade,

Materials science and the sensor revolution

For the past decade, we have been investigating strategies to develop ways to provide chemical sensing platforms capable of long-term deployment in remote locations1-3. This key objective has been driven by the emergence of ubiquitous digital communications and the associated potential for widely deployed wireless sensor networks (WSNs). Understandably, in these early days of WSNs, deployments have been based on very reliable sensors, such as thermistors, accelerometers, flow meters, photodetectors, and digital cameras. Biosensors and chemical sensors (bio/chemo-sensors) are largely missing from this rapidly developing field, despite the obvious value offered by an ability to measure molecular targets at multiple locations in real-time. Interestingly, while this paper is focused on the issues with respect to wide area sensing of the environment, the core challenge is essentially the same for long-term implantable bio/chemo-sensors4, i.e.; how to maintain the integrity of the analytical method at a remote, inaccessible location

Autonomous valves in micro-fluidic manifolds based on versatile photoresponsive ionogels

Versatility in valve actuation within micro-fluidic devices is very desirable since precise flow control, provision of exact reagent amounts, contamination prevention between reagents, autonomy, disposability and low-cost manufacture are factors that cannot be found today for microfluidic valves. Valves made using photo-responsive gels are of great interest as functional materials within micro-fluidic systems since actuation can be controlled by light irradiation, without physical contact, unlike equivalent electroactuated valves. Nevertheless, their poor versatility, slow response times and limited robustness render them currently as scientific curiosities rather than ideally functioning devices.[1] The incorporation of photoresponsive gels with ionic liquids (ILs), ionogels, produces hybrid materials with many advantages over conventional materials. For example, through the tailoring of chemical and physical properties of ILs, robustness, acid/ base character, viscosity and other critical operational characteristics can be finely adjusted. Therefore, we can tune the characteristics of the ionogels by changing the IL and so more closely control the actuation behaviour of micro-valves made from these novel materials. In this paper, we present the preparation and performance of four different ionogels as micro-valves in microfluidic systems. It was found that simply varying the ILs, actuation can be modulated on demand

Photo-responsive ionogels: versatile flow control in micro-fluidic manifolds

This paper presents the synthesis, characterization and micro-valve actuation in a micro-fluidic device of novel polymeric materials based on phosphonium ionic liquids (ILs), ionogels. When photo-responsive gels are co-polymerised within different IL matrixes, high versatility in the ionogels actuation can be achieved when incorporated in a micro-fluidic system as micro-valves

Liposomal-polyene preliposomal powder and method for its preparation

A method is disclosed for preparing a stable preliposomal powder which, when reconstituted with water or saline solution, forms a suspension of liposomes containing a polyene drug, such as nystatin. The method involves the steps of combining at least one phospholipid with a first organic solvent to form a first solution, adding a clarifying amount of water to the first solution, combining a polyene with a second organic solvent to form a second solution, combining the first and second solutions to produce a substantially clear combined solution, and then removing the organic solvents, leaving a powder.Board of Regents, University of Texas Syste