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1.
Students (N = 167) from the 4th, 8th, and 11th grades sorted meals, listed on individual cards, according to whether they would or would not eat them. Students were told to either consider eating the meals at home or at school. Forty-two different meals were selected from a pool of unique meals created by students in a previous study. The meals differed in head component, the presence or absence of vegetables, and the number of different foodstuffs. On average, approximately half of the meals were deemed acceptable, but older students accepted more meals than younger ones, boys accepted more meals than girls, and meals to be consumed at home were accepted more than those to be consumed at school. In addition, students tended to accept meals comprised of a small number of foodstuffs that did not contain vegetables. The also chose more meat-based meals over those containing fish or soup. These results suggest that students have rather unique food preferences that do not correspond well with nutritional standards. In order to address this problem we recommended that students be given more good choices in the school cafeteria through the introduction of a two-meal system and salad bars. 相似文献
2.
Natural rubber vulcanizates of two formulations, with sulfur/N-cyclohexyl-2-benzothiazolesulfenamide (CBS) and tetramethylthiuram disulfide (TMTD), respectively, were analyzed by pyrolysis gas chromatography. A sulfur-selective flame-photometric detector was utilized. The main pyrolysis products were identified as CS2 and some thiophenes. The yields of the pyrolysis products from the two types of rubber were very different. The yields also varied with the curing time of the rubbers. 相似文献
3.
Borage oil sterols were isolated by TLC and characterized using GC and GC-MS. Several diunsaturated Δ5-sterols, some of them not previously recorded in vegetable oils, were found. Of these, 24-methylcholesta-5,23-dienol and
24-ethylcholesta-5,23-dienol could be useful markers for borage oil. Two other diunsaturated Δ5-sterols that are rarely found in vegetable oils, 24-methylcholesta-5,24(25)-dienol and 24-ethylcholesta-5,24(25)-dienol,
were identified. The diunsaturated C-24(28)-sterol, isofucosterol, was also found, as well as the monounsaturated Δ5-sterols campesterol and sitosterol. These are normally present in vegetable oils, which makes them unsuitable as markers
for borage oil. 相似文献
4.
Prolonged computer work with an extended neck is commonly believed to be associated with an increased risk of neck-shoulder disorders. The aim of this study was to compare neck postures during computer work between female cases with neck-shoulder disorders, and healthy referents. Based on physical examinations, 13 cases and 11 referents were selected among 70 female air traffic controllers with the same computer-based work tasks and identical workstations. Postures and movements were measured by inclinometers, placed on the forehead and upper back (C7/Th1) during authentic air traffic control. A recently developed method was applied to assess flexion/extension in the neck, calculated as the difference between head and upper back flexion/extension. Results: cases and referents did not differ significantly in neck posture (median neck flexion/extension: -10 degrees vs. -9 degrees ; p=0.9). Hence, the belief that neck extension posture is associated with neck-shoulder disorders in computer work is not supported by the present data. 相似文献
5.
Jan Gulliksen Bengt G ransson Inger Boivie Stefan Blomkvist Jenny Persson sa Cajander 《Behaviour & Information Technology》2003,22(6):397-409
The concept of user-centred systems design (UCSD) has no agreed upon definition. Consequently, there is a great variety in the ways it is applied, which may lead to poor quality and poor usability in the resulting systems, as well as misconceptions about the effectiveness of UCSD. The purpose of this paper is to propose a definition of UCSD. We have identified 12 key principles for the adoption of a user-centred development process, principles that are based on existing theory, as well as research in and experiences from a large number of software development projects. The initial set of principles were applied and evaluated in a case study and modified accordingly. These principles can be used to communicate the nature of UCSD, evaluate a development process or develop systems development processes that support a user-centred approach. We also suggest activity lists and some tools for applying UCSD. 相似文献
6.
Fish and shellfish products imported into Denmark are routinely analyzed for pathogenic Vibrio spp., particularly Vibrio cholerae, if products originate from subtropical or tropical areas. A V. cholerae strain that agglutinated commercial O139 antiserum but not the O1, Inaba, or Ogawa antisera was isolated from imported raw frozen shrimp. The toxigenicity of the strain was analyzed, and the results of a polymerase chain reaction showed that the V. cholerae strain did not contain the virulence genes ctx, tcpA, and zot, which are normally found in V. cholerae O1 and O139. The strain was resistant to colistin and spectinomycin. The high susceptibility of the strain to antimicrobial agents was confirmed by the lack of an SXT element, a self-transmissible, chromosomal genetic element that is normally present in 0139 strains and encodes resistance to sulfonamides, trimethoprim, and streptomycin. The strain contained two plasmids, in contrast to other O139 strains, which normally do not contain plasmids. The characteristics of the strain led to further agglutination testing with other antisera that are not commercially available, and the strain was found to agglutinate O155 antiserum in repeated testing. Manufacturers of 0139 antiserum should be aware of the closely related O antigens of the O139, O22, and O155 serogroups and should be aware that their commercial diagnostic O139 antiserum must be absorbed to remove cross-reacting agglutinins of O22 and O155 strains. 相似文献
7.
Background
Whole grain (WG) intake is associated with reduced risk of obesity, type 2 diabetes and cardiovascular disease, whereas type 2 diabetes increases the risk of cognitive decline and dementia. The purpose of this study was to investigate the effects of short-term intervention with WG rye on cognitive functions, mood and cardiometabolic risk markers in middle-aged test subjects.Method
Rye-based breads were provided to 38 healthy test subjects (aged 52-70y) during three consecutive days in a crossover study design, using white wheat flour bread (WWB) as a reference. The rye-based bread consisted of a WG rye kernel/flour mixture (1:1 ratio) supplemented with resistant starch type 2 (RS2) (RB?+?RS2). The last bread portion was ingested at 2100 h, and cognitive function, mood and cardiometabolic risk markers were determined the following morning, 11???14 h post intake.Results
In comparison to WWB, the RB?+?RS2 product increased ratings of mood parameters (valance, P?<?0.001; activation P?<?0.05). No differences were seen in the cognitive tests depending on intervention (P?>?0.05). RB?+?RS2 increased insulin sensitivity (P?<?0.05), fasting levels of gut hormones (PYY, P?<?0.05; GLP-2, P?<?0.01) and fasting concentrations of plasma acetate, butyrate and total SCFA (P?<?0.001). In contrast, fasting levels of IL???1β were decreased (P?<?0.05). Insulin sensitivity was positively correlated with working memory test performance (P?<?0.05).Conclusions
This study display novel findings regarding effects of WG rye products on mood, and glucose and appetite regulation in middle-aged subjects, indicating anti-diabetic properties of WG rye. The beneficial effects are suggested to be mediated through gut fermentation of dietary fiber in the RB?+?RS2 product.Trial registration
The study was retrospectively registered at ClinicalTrials.gov, register number NCT03275948. Registered September 8 2017.8.
Sensors: Detection Beyond Debye's Length with an Electrolyte‐Gated Organic Field‐Effect Transistor (Adv. Mater. 5/2015) 下载免费PDF全文
9.
The retention of five proteins was compared on a set of three strong cation exchange adsorbents that differed in spacer arm chemical structure and length. The adsorbents included a commercial product, Amersham Biosciences SP Sepharose Fast Flow, containing a six-carbon spacer between the agarose matrix and the anionic ligand, and two custom-prepared materials. One of the custom adsorbents contained a spacer of about half the length of the SP Sepharose Fast Flow, and the other contained no spacer arm. The adsorbent with no spacer arm was found to be significantly more retentive for all of the test proteins examined, in both isocratic and gradient elution tests. Reducing the spacer arm length by half resulted in increased retention for four of the five proteins, but this increase was less than what was observed when the spacer arm was eliminated. Retention increases were obtained without increasing the density of the anionic charge groups and appear to result from an enhancement of electrostatic or secondary nonelectrostatic interactions, or both. The results indicate that spacer arm length may be a useful variable in manipulating stationary-phase retention properties. 相似文献
10.
The hybridisation of thiol-modified single-stranded DNA (SH-ssDNA) embedded in lipoate or hydrophilic polymer monolayers on gold have been studied through the technique of surface plasmon resonance (SPR). SH-ssDNA and the blocking agents were co-adsorbed on gold from the same solution or the surface was post-treated with the blocking agents. The assembling process is allowed to take place for only 10 min. Binding of non-complementary and complementary DNA is dependent both on the blocking agent and on the assembling method used. The lowest non-complementary binding and the highest complementary binding of DNA was obtained with a layer assembled from a binary solution of SH-ssDNA and the lipoate blocking agent. 相似文献