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881.
Rihaakuru is a shelf stable fish paste product formed from a fish soup prepared from tuna. Histamine contamination is a food safety issue with this product that is manufactured from tuna fish that has been temperature abused. Histamine concentrations decreased between 31% and 73% in Rihaakuru stored for 10months at either -80, 4 or 30°C. This appears to be a property of the product as histamine solutions are reported to be stable, at least under frozen storage. The risk of histamine food poisoning due to Rihaakuru may reduce during the storage of the product. 相似文献
882.
Hinton TG Kaplan DI Knox AS Coughlin DP Nascimento RV Watson SI Fletcher DE Koot BJ 《Environmental science & technology》2006,40(14):4500-4505
We hypothesized that adding micaceous minerals to 137Cs-contaminated aquatic systems would serve as an effective in situ remediation technique by sequestering the contaminant and reducing its bioavailability. Results from several laboratory studies are presented from which an effective amendment material was chosen for a replicated field study. The field study was conducted over a 2-year period and incorporated 16 3.3-m diameter column-plots (limnocorrals) that were randomly placed in a 137Cs-contaminated pond. The limnocorrals received three rates of amendment treatments to their water surfaces. The amendment material was a commercially available mineral with high sorption (Kd > 9000 L kg(-1)) and low desorption (<20%) characteristics for cesium, even in the presence of high concentrations of the competing cation, NH4+. In the treated limnocorrals, 137Cs concentrations were reduced some 25-30-fold in the water, 4-5-fold in aquatic plants, and 2-3-fold in fish. The addition of the amendment did not adversely affect water chemistry, although increased turbidity and subsequent siltation did alter the aquatic macroinvertebrate insect community. This in situ technology provides a valuable, less-environmentally intrusive alternative to costly ex situ technologies that require the contaminated sediment to be excavated prior to treatment, or excavated and disposed of elsewhere. 相似文献
883.
New guidelines have been developed and trialled in Australia to assist urban stormwater managers to assess options for projects that aim to improve urban waterway health. These guidelines help users to examine the financial, ecological and social dimensions of projects (i.e., the so-called "triple-bottom-line"). Features of the assessment process described in the guidelines include use of multi criteria analysis, input from technical experts as well as non-technical stakeholders, and provision of three alternative levels of assessment to suit stormwater managers with differing needs and resources. This paper firstly provides a background to the new guidelines and triple-bottom-line assessment. The assessment methodology promoted in the new guidelines is then briefly summarised. This methodology is compared and contrasted with European guidelines from the "SWARD" project that have been primarily developed for assessing the relative sustainability of options involving urban water supply and sewerage assets. Finally, the paper discusses how assessment methodologies that evaluate the financial, ecological and social dimensions of projects can, under some circumstances, be used to evaluate the relative progress of options for urban water management on a journey towards the widely pursued, but vaguely defined goal of "sustainable development". 相似文献
884.
Brown LE Mitchell G Holden J Folkard A Wright N Beharry-Borg N Berry G Brierley B Chapman P Clarke SJ Cotton L Dobson M Dollar E Fletcher M Foster J Hanlon A Hildon S Hiley P Hillis P Hoseason J Johnston K Kay P McDonald A Parrott A Powell A Slack RJ Sleigh A Spray C Tapley K Underhill R Woulds C 《The Science of the total environment》2010,409(2):256-369
Several recent studies have emphasised the need for a more integrated process in which researchers, policy makers and practitioners interact to identify research priorities. This paper discusses such a process with respect to the UK water sector, detailing how questions were developed through inter-disciplinary collaboration using online questionnaires and a stakeholder workshop. The paper details the 94 key questions arising, and provides commentary on their scale and scope. Prioritisation voting divided the nine research themes into three categories: (1) extreme events (primarily flooding), valuing freshwater services, and water supply, treatment and distribution [each > 150/1109 votes]; (2) freshwater pollution and integrated catchment management [100-150 votes] and; (3) freshwater biodiversity, water industry governance, understanding and managing demand and communicating water research [50-100 votes]. The biggest demand was for research to improve understanding of intervention impacts in the water environment, while a need for improved understanding of basic processes was also clearly expressed, particularly with respect to impacts of pollution and aquatic ecosystems. Questions that addressed aspects of appraisal, particularly incorporation of ecological service values into decision making, were also strongly represented. The findings revealed that sustainability has entered the lexicon of the UK water sector, but much remains to be done to embed the concept operationally, with key sustainability issues such as resilience and interaction with related key sectors, such as energy and agriculture, relatively poorly addressed. However, the exercise also revealed that a necessary condition for sustainable development, effective communication between scientists, practitioners and policy makers, already appears to be relatively well established in the UK water sector. 相似文献
885.
J. R. Vaughan G. R. Brookes M. A. Fletcher D. P. M. Wills 《Concurrency and Computation》1991,3(3):187-201
Data which is stored as a terrain data base is to be displayed graphically in a real-time application. Various parallel configurations of processing elements have been used to achieve the required performance. The results which have been achieved using transputers as the processing elements are presented in this report. 相似文献
886.
DA Danford KJ Salaymeh AB Martin SE Fletcher CH Gumbiner 《Canadian Metallurgical Quarterly》1999,134(1):76-81
The role of the adrenals in the polycystic ovary syndrome (PCOS) is debated. Both single steroid-converting enzyme abnormalities and increased adrenal activity have received support. The conventional Synacthen test using pharmacological doses of ACTH results in unphysiological levels of ACTH. Therefore, we used insulin-induced hypoglycemia (0.15 IU/kg BW) to asses the responses of ACTH, cortisol, pregnenolone, 17-hydroxypregnenolone, dehydroepiandrosterone, progesterone, 17-hydroxyprogesterone, and androstenedione in 18 women with PCOS and in 17 normal women of similar age and body mass index. The blood glucose concentration at 30 min was 2 mmol/L or less in all women, i.e. well below the threshold of the hormonal counterregulatory response. The women with PCOS showed a lower ACTH response, expressed as the maximum increment above basal [mean (95% confidence interval): PCOS, 11.1 (6.9-15.3); controls, 19.9 (13.8-26) pmol/L; P < 0.05], but a quantitatively comparable [PCOS, 207.2 (148.5-266.5); controls, 167.1 (100.6-233.2) nmol/L; P = NS] and more prompt cortisol response than the controls (by chi2 test, P < 0.05), resulting in a higher molar ratio between the maximum increments of cortisol and ACTH [PCOS, 13.9 (8.7-19); controls, 8.8 (5.7-12); P < 0.05]. The women with PCOS did, however, show a more rapid decline in cortisol levels than the controls (P < 0.05 at 120 and 180 min). The responses of the androgens and intermediate adrenal steroids were similar in women with PCOS and controls. The findings suggest an adaptation to increased adrenal reactivity to endogenous ACTH in women with PCOS. Exposure to hypoglycemia as a model of stress was not followed by hypersecretion of adrenal androgens and revealed no signs of steroid enzyme disturbances in women with PCOS. 相似文献
887.
A. S. Reber's (see record 1993-32264-001) proposition that the implicit learning system should demonstrate invariance of intellectual level (IQ) was examined by comparing 20 children with intellectual disability (mean mental age [MA]?=?approximately 5.8 years) with 20 intellectually gifted children (mean MA?=?approximately 12.4 years) of similar chronological age (CA; approximately 9.5 years). Implicit learning was assessed using a task involving covariation of 2 incidental cues. Explicit learning was assessed using a task of similar logical structure. Contrary to the IQ-invariance proposition, implicit learning as well as explicit learning varied with intellectual level. A secondary aim was to distinguish the contributions of CA, IQ, and MA to implicit learning. This was done by combining the samples of children in the present study with 2 samples of younger and older children of average ability from a study by M. Maybery, M. Taylor, and A. O'Brien-Malone (see record 1996-00932-001). Analyses showed that MA is critical to implicit learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
888.
J.A. Liendo M.A. Bernal A.C. Gonzlez D.D. Caussyn N.R. Fletcher O.A. Momotyuk R.M. Muruganathan B.T. Roeder I. Wiedenhver T. Fischer K.W. Kemper P. Barber L. Sajo-Bohus 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(20):3424-3430
Evaporated amniotic fluid (AF) targets have been bombarded with a 13 MeV 6Li3+ beam. Forward angle data have served to identify the 1H(6Li,1H)6Li reaction as an alternative for hydrogen characterization of such organic samples. Detected 6Li ions elastically scattered from C, N, O, Na and Cl can also be used to determine the concentrations of these elements in AF. The analyzed AF samples have been diluted with distilled water. The effect of sample dilution on the improvement of spectrum energy resolution has been observed, confirming previous reports. The hydrogen concentration determined in the studied AF targets is shown to vary linearly with sample dilution. Two detector arrangements have been used to find out which detection scheme is the most convenient. The combination of a counter telescope and a single detector, set up at the same polar angle on the opposite side of the beam, seems to be the best choice to have a reliable particle identification and an adequate energy resolution simultaneously. 相似文献
889.
Jesse Fletcher Giacinta Parish John Dell Adrian Keating 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(32):2300655
Direct laser writing (DLW) of mesoporous porous silicon (PS) films is shown to selectively create spatially separated nitridized and carbonized features on a single film. Nitridized or carbonized features are formed during DLW at 405 nm in an ambient of nitrogen and propane gas, respectively. The range of laser fluence required to create varying feature sizes while avoiding damage to the PS film is identified. At high enough fluence, nitridation using DLW has been shown as an effective method for laterally isolating regions on the PS films. The efficacy in preventing oxidation once passivated is investigated via energy dispersive X-ray spectroscopy. Changes in composition and optical properties of the DL written films are investigated using spectroscopic analysis. Results show carbonized DLW regions have a much higher absorption than as-fabricated PS, attributed to pyrolytic carbon or transpolyacetylene deposits in the pores. Nitridized regions exhibit optical loss similar to previously published thermally nitridized PS films. This work presents methods to engineer PS films for a variety of potential device applications, including the application of carbonized PS to selectively engineer thermal conductivity and electrical resistivity and of nitridized PS to micromachining and selective modification of refractive index for optical applications. 相似文献
890.