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排序方式: 共有402条查询结果,搜索用时 15 毫秒
101.
Food safety self-reported behaviors and cognitions of young adults: results of a national study 总被引:4,自引:0,他引:4
Byrd-Bredbenner C Maurer J Wheatley V Schaffner D Bruhn C Blalock L 《Journal of food protection》2007,70(8):1917-1926
With limited opportunities to learn safe food handling via observation, many young adults lack the knowledge needed to keep them safe from foodborne disease. It is important to reach young adults with food safety education because of their current and future roles as caregivers. With a nationwide online survey, the demographic characteristics, self-reported food handling and consumption behaviors, food safety beliefs, locus of control, self-efficacy, stage of change, and knowledge of young adults with education beyond high school (n = 4,343) were assessed. Young adults (mean age, 19.92 +/- 1.67 SD) who participated were mainly female, white, never married, and freshmen or sophomores. Participants correctly answered 60% of the knowledge questions and were most knowledgeable about groups at greatest risk for foodborne disease and least knowledgeable about common food sources of foodborne disease pathogens. They reported less than optimal levels of safe food handling practices. Young adults generally had a limited intake of foods that increase the risk of foodborne disease, positive food safety beliefs, an internal food safety locus of control, and confidence in their ability to handle food safely, and they were contemplating an improvement in, or preparing to improve, their food handling practices. Females significantly outperformed males on nearly all study measures. Future food safety educational efforts should focus on increasing knowledge and propelling young adults into the action stage of safe food handling, especially males. Efforts to improve knowledge and, ultimately, food safety behaviors are essential to safeguard the health of these young adults and enable them to fulfill the role of protecting the health of their future families. 相似文献
102.
Kendall PA Elsbernd A Sinclair K Schroeder M Chen G Bergmann V Hillers VN Medeiros LC 《Journal of food protection》2004,67(11):2578-2586
A reliable and validated set of food safety behavior questions that could be used with confidence when evaluating food safety education programs was identified in this study. A list of 29 food-handling and consumption behaviors rank-ordered within five pathogen control factors by nationally recognized food safety experts was the basis for the development of the behavior questions. Questions were evaluated for reliability and several forms of validity. During a kitchen activity session, 70 graduates of a nutrition education program completed four food preparation tasks while being observed and videotaped. The individuals also participated in an in-depth interview to validate behaviors that could not be observed during the food preparation activity, e.g., refraining from preparing food for others when experiencing diarrhea. Criterion validity was established by comparing questionnaire responses to observed behavior and interview responses. Twenty-eight questions met the validity criterion (> or = 70% agreement between observed and interviewed responses and self-reported responses), with three or more questions from each of five pathogen control factor areas. Observation assessments revealed that hand washing was more likely to be performed prior to beginning food preparation than between working with raw meats and fresh produce. Errors in methods of washing hands, utensils, and preparation surfaces between food preparation tasks were common. Most participants did not use thermometers to evaluate doneness but still cooked to safe internal temperatures. The results provide a tool that educators can use to evaluate food safety programs and will help guide the development of more effective food safety education programs targeting needed improvements in behavioral skills. 相似文献
103.
Ainara Aguadero Lydia Fawcett Samuel Taub Russell Woolley Kuan-Ting Wu Ning Xu John A. Kilner Stephen J. Skinner 《Journal of Materials Science》2012,47(9):3925-3948
One of the major challenges in developing electrochemical devices for energy generation has been the identification and development
of materials with outstanding performance at reduced (intermediate) temperatures (500–700 °C), increasing the durability and
lowering the cost of the device. A solid-state electrochemical cell is in outline a simple device consisting of three components:
anode, electrolyte and cathode. The function of each component is critical to cell performance, and as interest in fuel cells
and electrolysers has gathered pace, many materials have been evaluated as functional components of these cells. Typically,
the requirement for new materials development has been the drive to lower operation temperature, overcoming sluggish reaction
kinetics in existing materials. Novel materials for the functional components of both electrolysers and fuel cells are introduced,
with emphasis placed on the air electrode and electrolyte, with the potential of new classes of materials discussed, including
layered materials, defect fluorites and tetrahedrally coordinated phases. Furthermore, the opportunity presented by thin film
deposition to characterize anisotropic transport in materials and develop devices based on thin films is discussed. 相似文献
104.
Aluminosilicates are widely used as sorbent materials, ion exchangers, and catalysts. While they are often synthesized by hydrothermal methods, microorganisms may open “green” synthesis ways. Diatoms can incorporate aluminum into their micro- and nanostructured silica-based cell walls. Thus, diatoms create intricately structured aluminosilicate materials. The present study investigates not only possible morphological changes during the in vivo Al-enrichment of the diatom species Thalassiosira pseudonana, but also the increase of the specific surface area of Al-enriched biosilica in vitro by etching with alkaline solutions. 相似文献
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108.
Michi Izumi Alison M. Sweeney Daniel DeMartini James C. Weaver Meghan L. Powers Andrea Tao Tania V. Silvas Ryan M. Kramer Wendy J. Crookes-Goodson Lydia M. M?thger Rajesh R. Naik Roger T. Hanlon Daniel E. Morse 《Journal of the Royal Society Interface》2010,7(44):549-560
Many cephalopods exhibit remarkable dermal iridescence, a component of their complex, dynamic camouflage and communication. In the species Euprymna scolopes, the light-organ iridescence is static and is due to reflectin protein-based platelets assembled into lamellar thin-film reflectors called iridosomes, contained within iridescent cells called iridocytes. Squid in the family Loliginidae appear to be unique in which the dermis possesses a dynamic iridescent component with reflective, coloured structures that are assembled and disassembled under the control of the muscarinic cholinergic system and the associated neurotransmitter acetylcholine (ACh). Here we present the sequences and characterization of three new members of the reflectin family associated with the dynamically changeable iridescence in Loligo and not found in static Euprymna iridophores. In addition, we show that application of genistein, a protein tyrosine kinase inhibitor, suppresses ACh- and calcium-induced iridescence in Loligo. We further demonstrate that two of these novel reflectins are extensively phosphorylated in concert with the activation of iridescence by exogenous ACh. This phosphorylation and the correlated iridescence can be blocked with genistein. Our results suggest that tyrosine phosphorylation of reflectin proteins is involved in the regulation of dynamic iridescence in Loligo. 相似文献
109.
We perform numerical simulations of Stokes flow through ordered arrays of fibers of square cross-section. The results for the permeability of single-size-fiber arrays are in very good agreement with the well-known correlation of Jackson and James, provided that an effective radius of equivalent cylindrical fibers is used with the same cross-sectional area. Then, we consider arrays of mixtures of different-sized fibers and test several mixing rules, proposed for estimating the composite permeability. The two most well-known, namely, the unweighted- and the volume-averaged resistivity rules give good predictions for not too large size-ratios, yet they systematically overestimate and underestimate the numerical results, respectively. Then, it appears almost self-evident that a combination of the above two mixing rules would provide a better prediction. Indeed, the geometric mean gives excellent agreement with the numerical results over an extended range of size ratios and relative volume fractions. 相似文献
110.
Fisher Christine Warmack Bruce J. Yu Yongchao Skolrood Lydia N. Li Kai Joshi Pooran C. Saito Tomonori Aytug Tolga 《Journal of Materials Science》2021,56(22):12596-12606
Journal of Materials Science - We report the design and scalable fabrication of a low-cost and low-power polyaniline-based (PANI) ammonia (NH3) gas sensor on polyimide (PI) substrates using... 相似文献