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Summary  

There is an increasing need in industry, arising from both economic and environmental considerations, to reduce costs and improve product quality through the use of automation. The use of on-line analysis instrumentation provides plant operators with a means for continuous measurement and rapid response. This can result in better control of process efficiency, product quality and resource utilization, all of which produce significant economic and environmental benefits. On-line measurement of bulk elemental composition is important in many industrial applications and is best achieved with highly penetrating neutron-gamma techniques. This paper presents recent work by CSIRO Minerals on the development and implementation of such a technique, NITA (neutron inelastic-scattering and thermal-capture analysis). NITA is distinct from the more common PGNAA (prompt neutron gamma activation analysis) technique in its use of fast neutron sources to generate inelastic scattering reactions, and in its consequent ability to excite gamma-rays from industrially important elements such as carbon and oxygen. The paper will compare the features of NITA and PGNAA analysers and will discuss applications of NITA in industry, including the on-line analysis of composition in pyrometallurgical applications and the on-conveyor belt monitoring of cement raw meal and coal.

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The objective of this trial was to study the effect of rancid feeds on the health status and growth of rats and to determine the pathological changes induced by dietary rancidity. Forty-two weaned male rats (body weight: 69.3 ± 1.0 g) were divided into seven experimental groups (n = 6 each). Rats in the different groups were fed diets containing meat-and-bone meal at an inclusion rate of 19 to 22%, low or high in peroxides and high in organic acids, with or without antioxidant. The diets were isoproteic (10%) and isolipidic (6%). During the 26-day-long trial (5 days for adjustment and 21 days for the main period) the body weight gain and the feed consumption were recorded. At the end of the trial detailed gross and histopathological examinations were performed. Feeding high-peroxide feed mixtures for 21 days significantly (P < 0.05) decreased feed intake and liveweight gain, while high organic acid concentration had only slight negative effects. Antioxidant supplementation alleviated the harmful effects, especially in the high-peroxide group. The ingestion of rancid feed mixtures and the subsequent decreased feed intake caused a decrease of glycogen content in the hepatocytes, accompanied by a slight centrolobular fatty infiltration. Peroxides caused lymphocyte depletion in the spleen, decreased the size of Malpighian bodies and the number of lymphoblasts, and altered the spermatogenesis. The protective effect of the antioxidant mixture seemed to be negligible in this respect.

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Commercial anti-uric acid diets for dogs may contain insufficient protein to sustain growth and lactation. In order to investigate the efficacy of an experimental purine-free diet moderately low in protein, its effect on urinary uric acid excretion was compared with that of a commercial dog food and a commercial low-protein anti-uric acid diet. The experimental diet, commercial dog food and commercial anti-uric acid diet contained 10.0, 12.8 and 5.0 g crude protein/MJ metabolizable energy, respectively. Twelve Dalmatian dogs were subjected to a 3 × 3 Latin square study. Although the plasma uric acid concentration was significantly lower when the dogs were fed either the commercial anti-uric acid diet (18.7 ± 6.0 µmol/l, mean ± SD, n = 12) or the experimental diet (19.2 ± 8.3 µmol/l), when compared to the commercial dog food (29.2 ± 11.1 µmol/l), no significant decrease of uric acid concentration in urine collected before the morning meal was seen. The average concentration of urinary uric acid was 60 µmol/l. There was a significant increase in the urea:creatinine ratio in urine when the dogs were fed the experimental diet compared to the commercial anti-uric acid diet, confirming that the experimental diet contained more protein. The experimental diet lowered plasma uric acid and was relatively high in protein and thus may be suitable for use in growing and lactating dogs to prevent ammonium urate urolithiasis.

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Abstract  

The combined analytical methods of thermal analysis and mass spectrometry have been applied in form of a newly developed prototype of a thermogravimetry — single photon ionisation time-of-flight mass spectrometer coupling (TG-SPI-TOFMS) to investigate the molecular patterns of evolved gases from several biomass samples as well as a crude oil sample. Single photon ionization (SPI) was conducted by means of a novel electron beam pumped argon excimer lamp (EBEL) as photon source. With SPI-TOFMS various lignin decomposition products such as guaiacol, syringol and coniferyl alcohol could be monitored. Furthermore, SPI allows the detection of aliphatic hydrocarbons, mainly alkenes, carbonylic compounds such as acetone, and furan derivatives such as furfuryl alcohol and hydroxymethylfurfural. More alkaline biomass such as coarse colza meal show intense signals from nitrogen containing substances such as (iso-)propylamine and pyrrole. Thermal degradation of crude oil takes place in two steps, evaporation of volatile components and pyrolysis of larger molecular structures at higher temperatures. Due to the soft ionisation, homologue rows of alkanes and alkenes could be detected on basis of their molecular ions. The obtained information from the thermal analysis/photo ionisation mass spectrometry experiments can be drawn on in comparison to the investigation of the primary products from flash pyrolysis of biomass for production of biofuels and chemicals.

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Indian way of life and vision of the world, life in the reductions and a response to the critics . This last article is a transcript and French translation of the last seven chapters (6 to 12) of Book 3 of the Latin manuscript by the Jesuit F. X. Eder on the missions or reductions in the Amerindian nations of the Moxos and Baures. It is the continuation of the first eight articles on the Jesuit missions in the now Bolivian Amazon basin in the 18th century , entitled:

  1. 1. Lima, Peru, and their inhabitants in the 18th century.
  2. 2. Jesuit missions in the now Bolivian Amazon basin in the 18th century.
  3. 3. Quality of the soil and description of the Indians.
  4. 4. Constructive works, beliefs and superstitions of the Indians, and how to convince them to join a reduction.
  5. 5. Trees, fruits, plants and mammals.
  6. 6. Birds, hunting, crocodiles, dolphins, fishes and fishing.
  7. 7 Fauna (last part), poisons and antidote, arms used by Indians for hunting and fishing.
  8. 8. Choice of a spouse, feasts and games, meals, food and drink, handicraft and arts.

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Acta Alimentaria
Authors: G. Balázs, I. Baracskai, M. Nádosi, A. Harasztos, F. Békés, and S. Tömösközi

The utilisation of microchip capillary electrophoresis has the potential to improve the capability of high throughput sample analysis of biomolecules. The aim of this study was to review this capability for cereal protein analysis.The commercially available lab-on-a-chip (LOC) technology was characterised in the separation of total proteins extracted from whole wheat meals. Important analytical parameters (such as repeatability) of both qualitative (molecular size estimation) and quantitative (relative percentage of total protein) aspects of LOC data were determined and discussed in the light of the need of possible applications. It revealed that the LOC has very good repeatability and reproducibility parameters; however the non-globular structure of the proteins can highly affect the sizing accuracy. Among other applications, the profiles were found to be suitable for wheat cultivar identification and to monitor environment related alterations on protein composition.After a confirmation process the LOC can be an appropriate tool for fast protein profile screening in cereal science and technology in diverse applications, and it can complement the conventional methods of analysis.

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Acta Alimentaria
Authors: R. García-Estepa, B. García-Villanova, E. Guera-Hernández, and J. Contreras-Calderón

In Spain the consumption of bakery products is increasing, while that of bread is decreasing. Baked goods have a high fat and sugar content, and their intake accounts for a high percentage of the food consumed by the population for breakfast, mid-morning and mid-afternoon meals. Twenty products, with and without cream and chocolate, were analysed. The nutrients examined were proteins, fats and fatty acids, carbohydrates, sugars, starch, and fibre. The values for carbohydrates ranged between 36.8% and 62.3%, and for sugars between 9.0% and 33.8%. The fat content ranged from 6.0% to 36.8%, while 76% of the saturated fatty acids (SFA) determined were atherogenic acids. In accordance with daily energy intake recommendations for SFA and sugars, the intake of one serving of the product provides 25% or more of the recommended energy from SFA for nine of the twenty baked goods tested, and more than 15% of the energy recommended from sugars for fourteen of these products.

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Acta Alimentaria
Authors: L. Bóna, N. Adányi, R. Farkas, E. Szanics, E. Szabó, Gy. Hajós, A. Pécsváradi, and E. Ács

Selenium (Se), a main antioxidant component in cereal grain, is essential for animals and human health reducing risk factors of many dangerous diseases. Over the past decades, intake of this trace element had dropped due to low Se content in large areas of European countries including Hungary. Se-rich, high-protein cereal products became a focus for both animal feed and human consumption. In the study, we examined the following: i) grain Se concentration of wheat ( Triticum aestivum L.) and triticale ( Triticosecale Wittm.) intake to detect intra-and inter-genetic variations and ii) possible comparison relationship of this trace element to end product integrity, quality and relevant technological aspects. Se content of the whole meal grain was tested via atomic absorption spectroscopy (AAS). Despite generally poor Se soil content of the experimental area where samples were collected, significant differences were found for both species. In general, triticale contained higher Se concentration than wheat did. Spring type cereals had significantly higher grain Se and protein concentration than those of winter ones. Grain Se content showed positive correlation with magnesium, copper, zinc, manganese, tocopherol and crude protein concentration. Remarkable intra-specific variations were found in Se concentration, however in future, additional studies, methods and resources will be required for identifying ways of increasing Se content in cereal foodstuff and feed.

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The epidemiological importance and serious health consequences of obesity is one of the most important medical issues. This cross-sectional study, including retrospective elements, aims to measure the occurrence and to seek for the possible reasons of obesity among elderly people in Hungary. The 266 elderly subjects (109 man over and 157 women over 60 years) were consecutive selected in primary care setting. Questionnaire on eating habits and life style, dietary record, medical check-up, anthropological measurements were performed. During the aging the meal frequency becomes more regular. People with lower body mass index ate frequently than overweight (BMI: 25–30 kg/m 2 ) or obese persons (BMI>30 kg/m 2 ). Obese people represented a smaller proportion in the older decades. According to the retrospective body-weight analysis the increase of body weight was significantly higher in the obese group then in the overweight category and by normal weighted people. Daily energy intake was high in both genders. In the obese group the ratio of people educated in primary school only, was much higher. The food choices were influenced by economic reasons in two-third of the studied population. Thirty percent of obese people had obese parents and 24% of them had obese children. Unfavorable nutritional habits and sedentary life style may have a prior responsibility for obesity. Prevention and medical intervention should be started in time at primary health care level.

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All boarding school provisions within the Slovak Republic are due to prepare meals under the guidance of the Ministry of Health that monitors recommended daily intakes of individual foods and dietary allowances of nutrients through scientific meetings. Calculations based on a nutrition model of a boarding school in four months were done to estimate the mean dietary intake of nitrates and nitrites, industrially added to foodstuffs, by children aged 7 to 10 years. Following recognised methodology of the Codex Alimentarius and the European Commission, it was assumed that nitrates and nitrites are used in the widest possible range of foods and at their maximum permitted levels, resulting in overestimation of intake values. The mean daily exposure of consumers with the lowest (21 kg) and the mean (26.5 kg) body mass to nitrates ranged from 0.6 to 6.7% and from 0.5 to 5.3% of their acceptable daily intake (ADI), respectively. For the same consumers, the mean daily exposure to nitrites ranged from 0 to 13.0% and from 0 to 10.3% ADI. No significant seasonal differences were obvious. The results indicated that the above-mentioned group of children is sufficiently protected from hazard of nitrates and nitrites in food.

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