Hormonal Profiling Reveals a Hormonal Cross-Talk During Fruit Decay in Sweet Cherries

Journal of Plant Growth Regulation - Although fruit decay in sweet cherries has been studied in some detail, information is still scarce about the possible role of phytohormones during postharvest....     

Magnetoresistive immunosensor for the detection of Escherichia coli O157:H7 including a microfluidic network

A hand held device has been designed for the immunomagnetic detection and quantification of the pathogen Escherichia coli O157:H7 in food and clinical samples. In this work, a technology to manufacture a Lab on a Chip that integrates a 3D microfluidic network with a microfabricated biosensor has been developed. With this aim, the sensing film optimization, the design of the microfluidic circuitry, the development of the biological protocols involved in the measurements and, finally, the packaging needed to carry out the assays in a safe and straightforward way have been completed. The biosensor is designed to be capable to detect and quantify small magnetic field variations caused by the presence of superparamagnetic beads bound to the antigens previously immobilized on the sensor surface via an antibody-antigen reaction. The giant magnetoresistive multilayer structure implemented as sensing film consists of 20[Cu(5.10nm)/Co(2.47 nm)] with a magnetoresistance of 3.20% at 235Oe and a sensitivity up to 0.06 Omega/Oe between 150Oe and 230Oe. Silicon nitride has been selected as optimum sensor surface coating due to its suitability for antibody immobilization. In order to guide the biological samples towards the sensing area, a microfluidic network made of SU-8 photoresist has been included. Finally, a novel packaging design has been fabricated employing 3D stereolithographic techniques. The microchannels are connected to the outside using standard tubing. Hence, this packaging allows an easy replacement of the used devices.     

Informed consent procedures: responsibilities of researchers in developing countries

We describe the informed consent procedures in a research clinic in Santiago, Chile, and a qualitative study that evaluated these procedures. The recruitment process involves information, counseling and screening of volunteers, and three or four visits to the clinic. The study explored the decision-making process of women participating in contraceptive trials through 36 interviews. Women understood the research as experimentation or progress. The decision to participate was facilitated by the information provided; time to consider it and to discuss it with partners or relatives; and perceived benefits such as quality of care, non-cost provision of methods and medical care. For some women, participation was an opportunity to express altruism. The main obstacles for participation were perceived side effects or risks. The final risk-benefit balance was strongly influenced by women's needs. Women perceived that the consent form benefited the clinic, proving that participants had made a free decision, and benefited the volunteers by warranting their right to free medical care. The most important problem detected was occasional misunderstanding of the information given on the form. We concluded that a full decision-making process enhances women's ability to exercise their right to choose, and assures research institutions that trials are conducted without coercion and that the participants are committed to the study. Researchers have the responsibility of conducting this process.     

Slime problems in the paper and board industry

 The latest trends in the paper industry have been towards manufacturing by a neutral or alkaline process, greater consumption of secondary fibres and the closing-up of the process water systems. Under these conditions of papermaking, the problems of deposits, corrosion and odours due to the microbiological activity increase considerably and therefore, runnability and production problems occur. To help our understanding of the current situation in the paper industry, this paper presents a review of the microorganism sources, the consequences of the microbiological activity upon the actual systems of manufacturing paper and board, and the current state of the different alternatives for its prevention and control, as well as the future trends to address environmental considerations. Received: 20 March 1996/Received revision: 23 May 1996/Accepted: 28 May 1996