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Data-based condition monitoring of a fluid power system with varying oil parametersHelwig, Nikolai, Schütze, Andreas 03 May 2016 (has links) (PDF)
In this work, an automated statistical approach for the condition monitoring of a fluid power system based on a process sensor network is presented. In a multistep process, raw sensor data are processed by feature extraction, selection and dimensional reduction and finally mapped to discriminant functions which allow the detection and quantification of fault conditions. Experimentally obtained training data are used to evaluate the impact of temperature and different aeration levels of the hydraulic fluid on the detection of pump leakage and a degraded directional valve switching behavior. Furthermore, a robust detection of the loading state of the installed filter element and an estimation of the particle contamination level is proposed based on the same analysis concept.
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Effect of selected lactic acid bacteria on the growth of food-borne pathogens and spoilage microorganisms in raw milk and milk productsAl-Zoreky, Nageb 27 August 1992 (has links)
Several lactic acid bacteria (LAB) of the Lactococcus, Lactobacillus,
Leuconostoc and Pediococcus genera were screened for inhibition of
food-borne pathogens and spoilage microorganisms in raw milk and
dairy products. Listeria monocytogenes was killed by Lactococcus
lactis subsp. lactis and Pediococcus pentosaceus due to their
production of bacteriocin-type inhibitors. Staphylococcus aureus
was not able to grow in raw milk at temperatures below 5°C even
without LAB being present. Gram negative Salmonella enteritidis.
Salmonella typhimurium and Escherichia coli, along with spoilage
bacteria of the genus Pseudomonas were dramatically inhibited by a
Lactobacillus species, designated AS-1, in raw and pasteurized milk
as well as in cottage cheese. However, other LAB were not able to
inhibit these organisms. Lactobacillus AS-1, did not produce
hydrogen peroxide but carbon dioxide was produced. The AS-1
strain was a gram positive coccobacillus, catalase and oxidase negative and produced DL-lactic acid. It deaminated arginine and
grew over a temperature range of 5°C to 45°C. It was also able to
ferment glucose, galactose, fructose and lactose in addition to 17
other carbohydrates. High numbers (107 CFU/ml) of AS-1 were
required to obtain complete inhibition of gram negative bacteria. A
selective medium (ASLM) for Listeria monocytogenes was developed
to follow the fate of this particular pathogen in association with LAB
in raw milk; other selective media were not able to inhibit the growth
of background flora of raw milk. ASLM was superior to four other
media in allowing only the growth of the target pathogen. For the
Lactococcus genus, a selective and differential agar medium (Alsan)
was formulated to selectively allow growth of Lactococcus spp. and
to differentiate between Lactococcus lactis subsp. lactis and the
biovariety diacetylactis, based on citrate utilization. / Graduation date: 1993
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Food Safety Know-howMisner, Scottie, Whitmer, Evelyn 12 1900 (has links)
1p. / Most of the "bad food" reported illnesses are due to bacterial contamination. Nearly all of these cases can be linked to improper food handling, both in our homes and in restaurants. This article briefly discusses the causes of food contamination and how to handle food safely.
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EFFECT OF AMMONIATION TREATMENT OF AFLATOXIN B1 ON MUTAGENICITY AND LEVELS OF AFLATOXIN M1 IN MILK.EWAIDAH, ESAM HASSAN. January 1984 (has links)
Six lactating Holstein cows received ammonia-treated or untreated aflatoxin-contaminated whole cottonseed (AFWC) or pure AFB₁ with their regular ration. Treatments were: AFWC (5,010 ppb AFB₁), 4 kg/day; the same AFWC treated with 1.5% anhydrous ammonia and 10% water; pure AFB₁ (2.2 mg twice daily) given in capsules; same amount AFB₁ treated with 50% NH₄OH for 26 days at 29°C; same amount ammoniated AFB₁ acidified to final pH of 5.0; same treatment as first except concentration of AFB₁ was 5,511 ppb. Levels of aflatoxin M₁ (AFM₁) in milk were monitored before, during, and after each treatment, and conversion and feed-through ratios were calculated. Feed consumption and milk production were also measured. Mutagenicity of acetone extracts of spray-dried milk was determined using Salmonella/microsomal assay. Ammoniation of AFWC did not reduce concentration of AFB₁ to below FDA action level; however, when the seed was fed, the concentration of AFM₁ in milk was less than FDA action level (0.5 μg/L). Ammoniation of AFB₁ was very effective in reducing levels of AFM₁ in milk of treated cows to less than the FDA action level. The average AFB₁/AFM₁ conversion ratios for the steady-state period of AFM₁ excretion in milk while giving AFWC and AFB₁ was 1.06% and 1.18%, respectively. Ammoniation of AFWC reduced the average AFB₁/AFM₁ ratio to 0.20% during the constant-state period of AFM(,1) excretion in milk. The ration containing AFWC (5,010 or 5,511 ppb AFB₁) caused a highly significant decrease in total milk production and feed consumption; ammoniated AFB₁ decreased total milk production significantly. Complete disappearance of AFM₁ from milk after discontinuing Treatments 1-6 was 120, 48, 95, 72, 96, and 120 h, respectively. Under these laboratory conditions, significance of the results of the Ames test was questionable.
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Migration and plant uptake of radionuclides in laboratory soil columns and field lysimeter with contaminated water tablesHu, Qing January 1998 (has links)
No description available.
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An investigation into the effects of annual residential change on asthmatic symptoms in university studentsLeitch, David Neil January 2001 (has links)
No description available.
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Development of an optimal hazard assessment method for contaminated sitesMorakinyo, Jimoh Akindele January 2001 (has links)
No description available.
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Studies on the interaction between arsenic (As) and rice varieties which differ in arsenate (As(V)) toleranceNigar, Meher January 2009 (has links)
In order to gain a better understanding of the mechanism of As(V) tolerance in rice, a number of hydroponic tolerance tests have been done on the interaction of As(V) with phosphate (PO<sub>4</sub><sup>3-</sup>), reduced glutathione (GSH) and O<sub>2</sub> supply. The PO<sub>4</sub><sup>3—</sup>As(V) interaction test revealed that increasing PO<sub>4</sub><sup>3-</sup> concentration reduces the toxicity of As(V). Low PO<sub>4</sub><sup>3-</sup> (0.05 mM) showed no protection against As(V) induced root inhibition, but higher PO<sub>4</sub><sup>3-</sup> (0.5 and 5 mM) showed marked protection, suggesting PO<sub>4</sub><sup>3-</sup> derived tolerance is not due to reduced PO<sub>4</sub><sup>3-</sup> transport that has been postulated in other grass species. The glutathione (GSH)-As(V) interaction test revealed a strong effect of GSH, increasing tolerance in rice. The O<sub>2</sub> supply test also revealed a significant effect with enhanced tolerance in rice. Therefore it can be suggested that PO<sub>4</sub><sup>3-</sup>, GSH and air bubbling supply all reduces As(V) toxicity in rice by increasing tolerance. The protection against As(V) provided by GSH and PO<sub>4</sub><sup>3-</sup> were not the same for two rice varieties, Azucena (As sensitive) and Bala (As tolerant). However these tolerance tests cannot explain why Azucena and Bala differ in susceptibility to As(V). Three green house pot experiments revealed that As(V) treatment reduces growth in dose dependent way. Total As concentration in the shoots and grain increases with the increasing concentration of the As(V) treatments. Surprisingly, application of PO<sub>4</sub><sup>3-</sup> does not alter As(V) toxicity. Anaerobic (lowland) soil shows higher shoot As concentration but uptake is lower. Rice genotypes show significant variation in their plant growth, total shoot As concentration and total As uptake which reveal that tolerant genotypes contain higher shoot As. Results of the hydroponics and pot experiments suggested that tolerance of rice is not derived from competition with As(V) at the PO<sub>4</sub><sup>3-</sup> transporters, but rather reflects another, as yet unknown, mechanism.
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Trace element levels in Mediterranean grainsLawgali, Youssef F. January 2010 (has links)
This is the first study to compare total arsenic (As) and other trace elements in the agricultural soils and grain of Eastern, Western and Southern Libya, North Africa and the Middle East (NA & MIDEA). Soil pot experiments and field experiments were conducted to determine the levels of As within wheat grains in Libya. In the soil pot experiments, wheat genotypes were planted in similar soils and yet differences in grain As concentration were found among the cultivars. The highest As accumulation was found in <i>T. durum; </i>however, in the field data the highest levels were found in <i>T. aestrivum.</i> The levels of As and other trace elements found in agricultural soils from the Eastern Western and Southern regions of Libya are examined. Mean As concentrations in the clay mineral agricultural soils of the Eastern Region were nearly 4.8 and 4.1 times higher than in the southern and western regions, respectively. It is possible that the parent material of that region contains elevated levels of As, which are then exhibited in the overlying soil. Differences in the levels of As and other trace elements found in the irrigated agricultural soil of Southern Libya were compared with non-irrigated soil from the same region. Concentrations of P, Zn and As in soil were higher in irrigated compared to non-irrigated soils, while the concentration of Cd is nearly the same in all soil samples. A market basket investigation was conducted to determine the total levels of As and Se in rice purchased from supermarkets. The average level of As in rice from NA & MIDEA is 0.22 mg/kg, comparable with average levels in Australia.
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Respuestas sobre Ia contaminacion de los alimentos en el hogar, comparacion entre madres o cuidadoras de Peru y Costa RicaLozada Urbano, Michelle, Miranda, Doris, Requena-Marcos, Lucy Sonia, Caro Soto, Carina, Gallegos Vergara, Clara, Xirinachs Salazar, Yanira 24 February 2015 (has links)
Objective: To compare the knowledge of mothers on food contamination in the home between the
towns of Peru and Costa Rica. Methods: It was conducted in a rural area of Peru (San Pablo and
Huascar) in San Juan de Lurigancho in Lima, and Costa Rica (San Vicente of Three Rivers). The
questions were part of a scale that was validated on an expert opinion. It was developed to measure
three components or domains.After validation,the instrument was applied in Costa Rica with a group
of mothers or caregivers with children under five. The application was developed in Peru in a
population with similar characteristics. Results:The sample consisted of 50 caregivers in Costa
Rica and 194 in Peru. There is no significant difference in the domains of contamination utensils
at home (p=O.750>0.05) and knowledge of child illness (p=0.060>0.05). Knowledge of agents of
contamination was highly significant (p=0.000<0.01). In general there is enough evidence to say
that knowledge of food contamination in the home are different in mothers of Peru and Costa Rica,
(p=0.013 <0.05). Conclusions: No significant differences on pollution and disease. There is highly
significant difference in knowledge about pollutants. Overall knowledge of food contamination in
the home were higher in mothers or caretakers of Peru.The scale can contribute to the planning of
interventions in the aspect of pollution in the home. / michellelozadau@gmail.com / Objetivo:Compararelconocimiento de las madres sabre Ia contaminaci6n de los alimentos en elhagar
entre las poblaciones de Peru y Costa Rica. Metodos:Se llev6 a cabo en una zona rural de Peru (San
Pablo y Huascar) en San Juan de Lurigancho en Lima,yen Costa Rica (San Vicente de Tres rfos).Las
preguntas formaron parte de una escala que fue validada bajo un juicio de expertos. Se elabor6
para medir tres componentes o dominies. Despues de Ia validaci6n, el instrumento fue aplicado en
Costa Rica a un grupo de madres o cuidadoras con nifios menores a cinco anos. La aplicaci6n en Peru
fue desarrollada en una poblaci6n con caracteristicas similares. Resultados: La muestra fue de
50 cuidadoras en Costa Rica y 194 en Peru. No existe diferencia significativa en los dominies
sabre contaminaci6n por utensilios en el hagar (p=O,750>0,05) y por conocimiento sabre enfermedades
del n1no (p=0,060 >0,05). El conocimiento sQbre agentes de contaminaci6n result6 ser
altamente significative (p=0,000<0,01). En generalexiste evidencias suficientes para afirmar que el
conocimiento de contaminaci6n de los alimentos en el hagar son diferentes en las madres del Peru y
Costa Rica, (p=0,013<0,05). Conclusiones: No existen diferencias significativas sabre
contaminaci6n y enfermedades. Existe diferencia altamente significativa en el conocimiento
sabre agentes contaminantes.En general el conocimiento de contaminaci6n de los alimentos en
elhogarfueron mas altas en las madres o cuidadoras del Peru. La escala puede contribuir a Ia
planificaci6n de las intervenciones en elaspecto de contaminaci6n en elhagar.
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