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Article
Publication date: 1 March 1984

H. Stolarski, T. Belytschko, N. Carpenter and J.M. Kennedy

A simple triangular shell element which incorporates the effects of coupling between membrane and flexural behaviour and avoids membrane locking is described. The element…

Abstract

A simple triangular shell element which incorporates the effects of coupling between membrane and flexural behaviour and avoids membrane locking is described. The element uses a discrete Kirchhoff bending formulation and a constant strain membrane element. For the purpose of permitting inextensional modes and thus avoiding membrane locking, a decomposition technique, which can also be viewed as a strain projection method, is used. The method is illustrated first for a beam element and then for a triangular shell element. Results are presented for a variety of linear static problems to illustrate its accuracy and some highly non‐linear problems to indicate its applicability to collapse analysis.

Details

Engineering Computations, vol. 1 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 11 January 2018

Piotr Firek, Michal Cichomski, Michal Waskiewicz, Ireneusz Piwoński and Aneta Kisielewska

The purpose of this paper is to present possibility of fast and certain identification of bovine serum albumin (BSA) by means of ion-sensitive field effect transistor…

Abstract

Purpose

The purpose of this paper is to present possibility of fast and certain identification of bovine serum albumin (BSA) by means of ion-sensitive field effect transistor (ISFET) structures. Because BSA can cause allergic reactions in humans, it is one of reasons for development of sensitive sensors to detect residual BSA. BSA is commonly used in biochemistry and molecular biology in laboratory experiments. Therefore, to better understand the mechanism of signal transduction in simulated biological environment and to elucidate the role of adsorption of biomolecules in the generation of a signal at the interface with biological systems, the measurements of ISFET current response in the presence of BSA as a reference protein molecule were performed.

Design/methodology/approach

To fabricate transistors, silicon technology was used. The ISFET structures were coupled to specially designed double-side printed circuit board holder. After modification of the field effect transistor (FET) device with 3-aminopropyltriethoxysilane (APTES), a sensor with high sensitivity toward reference biomolecules was obtained. The current–voltage (I-V) characteristics of structures with and without gate modification were measured. Keithley SMU 236/237/238 measurement set was used. Deionized water solution and 0.05 per cent BSA were used.

Findings

In this research, a method of preparation of a biosensor based on a FET was developed. Sensitivity of APTES-modified FET device toward BSA as a biomolecule was investigated. I-V relationships of FET devices (with and without modification), being the effect of the interactions with the solution containing 0.05 per cent BSA, were measured and compared to the measurements performed for solutions without BSA.

Originality value

Compared to SiO2-containing ISFETs without modification or other different dielectrics, the application of APTES as the part of the membrane induced significant increase in their sensitivity to BSA.

Details

Circuit World, vol. 44 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 1 July 2005

Y.T. Lo, W.M. Leung and H.Z. Cui

Cracks in the roof parapet wall and damage to the waterproofing membrane are the common defects of roof construction that require frequent maintenance. This paper seeks to…

Abstract

Purpose

Cracks in the roof parapet wall and damage to the waterproofing membrane are the common defects of roof construction that require frequent maintenance. This paper seeks to review the common defects of roof construction of medium‐rise buildings in sub‐tropical climates.

Design/methodology/approach

The research reported was carried out by the survey and analysis of 20 case study buildings. The modes of rooftop parapet wall dislocation are studied and the effects of thermal expansion and end conditions of the parapet wall on the damage to the waterproofing membrane are analysed.

Findings

Parapet wall dislocation failure is dependent on whether the ends are hinged or fixed. Failure usually leads to tearing of the waterproofing membrane.

Practical implications

Modification to the roof parapet wall design and to the selection of construction materials is suggested.

Originality/value

The modes of failure and proposed modification will be of interest to designers and those responsible for the maintenance of flat‐roofed buildings in sub‐tropical climates.

Details

Structural Survey, vol. 23 no. 3
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 1 January 1984

Alan Leewood and Joop C. Nagtegaal

The application of the finite element method for the design and analysis of fabric structures is discussed. The basic concepts are outlined, and illustrated with practical…

Abstract

The application of the finite element method for the design and analysis of fabric structures is discussed. The basic concepts are outlined, and illustrated with practical structures designed and analysed with the MARC General Purpose Finite Element Program. Difficulties associated with the strongly anisotropic nature of the fabric are considered and solutions to overcome these problems are offered.

Details

Engineering Computations, vol. 1 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 20 March 2018

Ilhem Ghodbane, Rochdi Kherrrat, Saida Zougar, Rim Lamari, Redouane Haddadji and Mohamed Saleh Medjram

The purpose of this work is to explore electrical properties of an electrochemical sensor designed for the detection of malachite green (MG) present in an aqueous solution.

Abstract

Purpose

The purpose of this work is to explore electrical properties of an electrochemical sensor designed for the detection of malachite green (MG) present in an aqueous solution.

Design/methodology/approach

The present sensor consists in the spatial coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of an ionophore (D2HPA), a polymer (polyvinylchloride [PVC]) and a plasticizer (dioctyl phthalate [DOP]). Several techniques have been used to characterize this sensor: the cyclic voltammetry, the electrochemical impedance spectroscopy and the optical microscopy. The sensibility, the selectivity and the kinetic study of a modified platinum electrode have been evaluated by cyclic voltammetry.

Findings

The obtained results reveal the possibility of a linear relationship between the current of reduction peaks and MG concentration. A linear response was obtained in a wide-concentration range that stretches from 10−5 to 10−13 mol L−1, with a good correlation coefficient (0.976) and a good detection limit of 5.74 × 10−14 mol L−1 (a signal-to-noise ratio of 3). In addition, the voltammetric response of modified electrode can be enhanced by adding a layer of Nafion membrane. Under this optimal condition, a linear relationship was obtained, with a correlation coefficient of 0.986 and a detection limit of 1.92 × 10−18 mol L−1.

Originality/value

In the present research, a convenient, inexpensive and reproducible method for the detection of MG was developed. The developed sensor is capable of competing against the conventional techniques in terms of speed, stability and economy.

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Article
Publication date: 1 October 1996

C. Musès

Presents consciousness as not only cognitive awareness in sensory, imaginational, remembered and dream contexts, but also as the awareness in all of us that is not…

Abstract

Presents consciousness as not only cognitive awareness in sensory, imaginational, remembered and dream contexts, but also as the awareness in all of us that is not necessarily accessed by or immediately accessible only to the conscious mind. Sees consciousness, because of its primal and pervasive nature, as the Holy Grail of the scientific quest. Provides examples of how it can be misunderstood and exposed to sources of confusion. Discusses the resulting scenarios and considers global re‐assessments, including one of evolutionary theory.

Details

Kybernetes, vol. 25 no. 7/8
Type: Research Article
ISSN: 0368-492X

Keywords

Content available
Article
Publication date: 24 February 2015

Teruhisa Komori

Late life depression is often associated with a poor response to antidepressants; therefore an alternative strategy for therapy is required. Although several studies have…

Abstract

Late life depression is often associated with a poor response to antidepressants; therefore an alternative strategy for therapy is required. Although several studies have reported that phosphatidylserine (PS) may be effective for late life depression and that omega-3 fatty acids DHA and EPA have also proven beneficial for many higher mental functions, including depression, no concrete conclusion has been reached. This study was performed to clarify the effect of PS and omega-3 fatty acid-containing supplement for late life depression by not only clinical evaluation but also salivary cortisol levels. Eighteen elderly subjects with major depression were selected for the study. In all, insufficient improvement had been obtained by antidepressant therapy for at least 6 months. The exclusion criteria from prior brain magnetic resonance images (MRI) included the presence of structural MRI findings compatible with stroke or other gross brain lesions or malformations, but not white matter hypersensitivities. They took a supplement containing PS 100 mg, DHA 119 mg and EPA 70 mg three times a day for 12 weeks. The effects of the supplement were assessed using the 17-item Hamilton depression scale (HAMD17) and the basal levels and circadian rhythm of salivary cortisol. The study adopted them as indices because: salivary cortisol levels are high in patients with depression, their circadian rhythm related to salivary cortisol is often irregular, and these symptoms are alleviated as depression improves. The mean HAM-D17 in all subjects taking the supplement was significantly improved after 12 weeks of taking the supplement. These subjects were divided into 10 non-responders and 8 responders. The basal levels and circadian rhythm of salivary cortisol were normalized in the responders while not in non-responders. PS and omega-3 fatty acids, or other elements of the supplement, may be effective for late life depression, associated with the correction of basal levels and circadian rhythm of salivary cortisol.

Details

Mental Illness, vol. 7 no. 1
Type: Research Article
ISSN: 2036-7465

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Article
Publication date: 10 April 2017

Konstantin Vishnevskiy and Andrei Yaroslavtsev

The purpose of this paper is to apply Foresight methodology to the area of nanotechnologies and new materials within the framework of Russian S&T Foresight 2030 aimed at…

Abstract

Purpose

The purpose of this paper is to apply Foresight methodology to the area of nanotechnologies and new materials within the framework of Russian S&T Foresight 2030 aimed at revelation of major trends, most promising products and technologies.

Design/methodology/approach

To achieve this goal, best international practice was analyzed that provided a solid basis for Russian S&T Foresight 2030 (section “Nanotechnology and new materials”). The study used a wide range of advanced Foresight methods adapted to Russian circumstances. During the Foresight study, the authors integrated “market pull” and research “technology push” approaches including both traditional methods (priority-setting, roadmaps, global challenges analysis) and relatively new approaches (horizon scanning, weak signals, wild cards, etc.).

Findings

Using the methods of the Foresight, the authors identified trends with the greatest impact on the sphere of nanotechnology and new materials, promising markets, product groups and potential areas of demand for Russian innovation technologies and developments in this field. The authors assessed the state-of-the-art of the domestic research in the area of nanotechnologies and new materials to identify “white spots”, as well as parity zone and leadership, which can be the basis for integration into international alliances and positioning of Russia as a center of global technological development in this field.

Originality/value

The results of applying Foresight methodology toward revelation of the most prospective S&T areas in the field of nanotechnologies and new materials can be used by a variety of stakeholders including federal and regional authorities, technology platforms and innovation and industrial clusters, leading universities and scientific organizations in formulation of their research and strategic agenda. Russian businesses including both large companies and small and medium-sized enterprises can use results of the study in creating their strategic R&D programs and finding appropriate partners.

Details

foresight, vol. 19 no. 2
Type: Research Article
ISSN: 1463-6689

Keywords

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Article
Publication date: 1 January 1994

Reducing Level of Alcohol in Inks ‐ A medium‐sized US ink manufacturer recently needed to reduce the level of alcohol in its bases for water‐based inks. Ciba Geigy…

Abstract

Reducing Level of Alcohol in Inks ‐ A medium‐sized US ink manufacturer recently needed to reduce the level of alcohol in its bases for water‐based inks. Ciba Geigy Pigments Division's Inks Technical Centre developed an improved formulation, containing half the alcohol of the previous one and 40 per cent more pigment to allow the ink producer to meet VOC limits and increase production efficiency, at no additional cost.

Details

Pigment & Resin Technology, vol. 23 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 15 February 2008

Stephen Osahon Uwaifo

The paper seeks to examine the health risks faced when using computer‐based systems by library staff in Nigerian libraries.

Abstract

Purpose

The paper seeks to examine the health risks faced when using computer‐based systems by library staff in Nigerian libraries.

Design/methodology/approach

The paper uses a survey research approach to carry out this investigation.

Findings

The investigation reveals that the perceived health risk does not predict perceived ease of use of computer‐based libraries. Even though a wide range of health hazards were identified in the libraries, the level of availability of ergonomic programmes to tackle them was low.

Practical implications

In general, librarians, university authorities, IT policy formulators and systems administrators should find this paper useful, as it educates them about the fact that perceived health risk does not significantly deter people from using information systems. This is due to the enormous benefits arising from the use of IT when compared with the manual systems.

Originality/value

The study offers new insights in the area of IT use by librarians in Nigerian universities. That the study found that prevailing health risks do not significantly deter people from using information systems means that it differs from other studies.

Details

Program, vol. 42 no. 1
Type: Research Article
ISSN: 0033-0337

Keywords

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