Detection of nematodes in cod (Gadus morhua) fillets by imaging spectroscopy

ABSTRACT:  A promising method for detection of parasites in whitefish fillets has been developed. By use of imaging spectroscopy it is possible to record both spectral and spatial information from an object. In this work it is shown that by applying a white light transmission setup and imaging spectroscopy to cod ( Gadus morhua ) fillets, it is possible to make spectral images containing information to differentiate between fish muscle and parasites. The spectral images are analyzed by discriminant partial least square regression as well as image-filtering techniques. The method identifies parasites on the surface of the fillets as well as embedded parasites. One parasite was detected at 0.8 cm below the fillet surface, which is 2 to 3 mm deeper than what can be found by manual inspection of fish fillets. The method is nonintrusive and should thus be feasible for industrial purposes.     

Systems biology of the neurospora biological clock

A major challenge of systems biology is explaining complex traits, such as the biological clock, in terms of the kinetics of macromolecules. The clock poses at least four challenges for systems biology: (i) identifying the genetic network to explain the clock mechanism quantitatively; (ii) specifying the clock's functional connection to a thousand or more genes and their products in the genome; (iii) explaining the clock's response to light and other environmental cues; and (iv) explaining how the clock's genetic network evolves. Here, the authors illustrate an approach to these problems by fitting an ensemble of genetic networks to microarray data derived from oligonucleotide arrays with approximately all 11 000 Neurospora crassa genes represented. A promising genetic network for the clock mechanism is identified.     

Improved Systems Understanding by Similarities and Analogies

ABSTRACT

A set of definitions of systems engineering concepts is the point of departure of this article. Those definitions are generic and cover the system and its life cycle, the systems engineering discipline, and the systems engineering process. A systems engineer must be able to analyze and understand systems first on a conceptual level independent of technology, that is, a technology-free functional analysis. More detailed knowledge and deeper insight into a concrete technology are required later. The systems engineer must be able to move from one system project to another, sometimes with entirely different technologies and requirements. This article points to a need for greater flexibility and easier adaptability on the part of the systems engineer. This need implies that the knowledge base and professional toolbox for the systems engineer must meet this requirement also. A way this requirement can be met is by system similarity and the principle of analogy between functional characteristics of systems.     

Short communication: Is consumption of a cheese rich in angiotensin-converting enzyme-inhibiting peptides,such as the Norwegian cheese Gamalost,associated with reduced blood pressure?

Epidemiological and clinical studies have shown that angiotensin-converting enzyme (ACE)-inhibiting peptides derived from dairy products may decrease blood pressure. These peptides have been identified in many cheeses, and Gamalost, a traditional Norwegian cheese, is particularly rich in these peptides. The aim of this cross-sectional study was to examine whether frequency of Gamalost intake was associated with blood pressure in a Norwegian population sample. Blood pressure and other clinical measurements, including the factors of metabolic syndrome, were obtained from 168 participants (56% female, mean age = 51 yr) who completed a questionnaire about dietary habits and other health-related factors. Mean Gamalost intake was 2 servings per week. The prevalence of hypertension was 23.8% in the population, with mean systolic and diastolic blood pressures of 128 and 78 mmHg, respectively. Intake of Gamalost was inversely associated with systolic blood pressure. Each increase in frequency unit of Gamalost intake corresponded to a reduction in systolic blood pressure of 0.72 mmHg, after controlling for sex, age, education, waist circumference, physical activity, smoking status, and dairy food intake. Results from this study indicate that consumption of Gamalost (or other foods rich in ACE-inhibiting peptides) may reduce blood pressure.     

Quantifying uncertainty under a predictive, epistemic approach to risk analysis

Risk analysis is a tool for investigating and reducing uncertainty related to outcomes of future activities. Probabilities are key elements in risk analysis, but confusion about interpretation and use of probabilities often weakens the message from the analyses. Under the predictive, epistemic approach to risk analysis, probabilities are used to express uncertainty related to future values of observable quantities like the number of fatalities or monetary loss in a period of time. The procedure for quantifying this uncertainty in terms of probabilities is, however, not obvious. Examples of topics from the literature relevant in this discussion are use of expert judgement, the effect of so-called heuristics and biases, application of historical data, dependency and updating of probabilities. The purpose of this paper is to discuss and give guidelines on how to quantify uncertainty in the perspective of these topics. Emphasis is on the use of models and assessment of uncertainties of similar quantities.     

On the resistance to penetration of stiffened plates,Part II: Numerical analysis

A series of indentation tests have been carried out quasi-statically on various configurations of stiffened panels. These represent hull plates in ships subjected to grounding or collision actions. The results of the scaled down tests are reported in the first part of this two-part companion paper. This part (II) presents results from numerical analyses with focus on fracture prediction.     

New trends in rock slope stability analyses

 The paper discusses alternative approaches to stability analyses including the traditional deterministic principle, the so-called partial factor principle and the probabilistic approach which assesses the probability of failure rather than the factor of safety. To illustrate the different principles and approaches, stability analyses of road cuts near Trondheim, central Norway, are used as examples. It is concluded that although the traditional deterministic approach has the advantage of being well established and easy to understand, to conform with new standards and guidelines it is likely to be replaced by the partial factor principle. To obtain the best possible basis for evaluation it is useful to include a probabilistic analysis. Received: 5 August 1999 · 28 August 1999     

Effect of surfactant concentration, pH, and shear rate on the rheological properties of aqueous systems of a hydrophobically modifed chitosan and its unmodified analogue

Oscillatory shear, shear relaxation and viscosity experiments have been carried out on semidilute solutions of chitosan and on a hydrophobically modified analogue (HM-chitosan) in 1% acetic acid. This was done in the presence of various amounts of cetyltrimethylammonium bromide (CTAB) and at different pH values. All the rheological measurements on the HM-chitosan solutions revealed significant polymer-surfactant interaction and pH effects. The observed rheological effects were least pronounced at pH ≈ 4, while a strong viscoelastic response was found at pH values of 1 and 5 in HM-chitosan solutions of low surfactant concentration. At these conditions, significant shear-thinning effects were observed. In semidilute solutions of unmodified chitosan, the influence of pH, surfactant concentration and shear rate on the rheological properties was moderate or insignificant. Received: 25 September 1996/Revised version: 30 October 1996/Accepted: 4 November 1996     

Assessment of different techniques for quantification of α-Al(FeMn)Si and β-AlFeSi intermetallics in AA 6xxx alloys

During homogenisation of AA 6xxx aluminium alloys, the platelike β-AlFeSi intermetallic phase will transform to a less Si-rich and more spheroidised α-Al(FeMn)Si phase which is more favourable for extrusion. In this study, several quantitative methods, which determine the relative volume fraction of α-Al(FeMn)Si and β-AlFeSi, are compared and an assessment of each method is made. The methods used are optical microscopy, scanning electron microscopy (SEM) in combination with electron dispersive X-ray (EDX) using polished samples, and X-ray diffraction (XRD) on intermetallics, extracted through selective dissolution of the Al matrix. The highest accuracy is obtained by using SEM/EDX analysis and applying two criteria.