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991.
Current theories of category learning posit separate verbal and nonverbal learning systems. Past research suggests that the verbal system relies on verbal working memory and executive functioning and learns rule-defined categories; the nonverbal system does not rely on verbal working memory and learns non-rule-defined categories (E. M. Waldron & F. G. Ashby, 2001; D. Zeithamova & W. T. Maddox, 2006). However, relatively little research has explored the importance of visual working memory or visual processing for either system. The authors investigated the role of working memory (Experiment 1a and 1b), visual processing (Experiment 2), and executive functioning for each system, using a concurrent task methodology. It was found that visual tasks with high executive functioning demands and verbal tasks with high or low executive demands disrupted rule-defined learning, whereas any visual task, regardless of executive functioning demand, disrupted non-rule-defined learning. Taken together, these results confirm the importance of verbal working memory and executive functioning for the verbal system and provide new evidence for the importance of visual processing for the nonverbal system. These results help to clarify understanding of the nonverbal system and have implications for multiple systems theories of category learning (F. G. Ashby, L. A. Alfonso-Reese, A. U. Turken, & E. M. Waldron, 1998). (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
992.
Shamey R Shepherd S Abed M Chargualaf M Garner N Dippel N Weisner N Kuehni RG 《Journal of the Optical Society of America. A, Optics, image science, and vision》2011,28(10):1962-1969
The aim of this study was to determine how accurately color-normal subjects that have received basic information about, but do not have practical experience with, the Natural Color System (NCS) can estimate the Heringian components of a representative selection of samples. Twenty-five color-normal subjects, taking part in two trials with at least a 24 h gap between assessments, selected four samples representing individual unique hues (uHs) from a set of 40 highly chromatic NCS samples on a rotatable tray. The samples selected for assessment of components were displayed to the subjects who estimated the hue components of 16 high-chroma samples, hue and white/black components of 16 tonal color samples, and three achromatic samples with different blackness values. Variability in selection of samples representing uHs as well as the relationship between the subjects' estimates of unique hue components and the defined values of the system was obtained. It was found that hues alone are easier to correctly estimate than hues together with white and black and that the components of colors of higher chroma are easier to estimate accurately than those of lower chroma. It was also found that, for R and G, the mean uH choices of subjects differed very little from the NCS's R and G, whereas selections for yellow and blue deviated, the former by 1.22 hue steps (slightly greener than G90Y), and the latter by 1.36 hue steps (represented approximately by R85B). This may impact the accuracy of color models that employ NCS unique hues. 相似文献
993.
994.
Sarah Bell 《The International journal of environmental studies》2013,70(5):581-589
Analysis of press reports of the onset of drought in Sydney in 2002 and London in 2006 shows different understandings of the relationship between infrastructure provision, individual behaviour and the environment. Drought is both a natural and cultural phenomenon requiring urban water managers to consider social as well as technical considerations in preparing for future droughts. 相似文献
995.
996.
Judith E. Innes Sarah Connick David Booher 《Journal of the American Planning Association. American Planning Association》2013,79(2):195-210
In 1994 an unusual, if not unique, collaborative effort emerged to manage the highly contested and interconnected system of waters, levees, and habitat in the San Francisco Bay Estuary and Sacramento-San Joaquin Delta. This CALFED Bay-Delta Program (CALFED) engaged 25 federal and state agencies and representatives of 35 major stakeholder groups and local agencies in a joint search for solutions to Bay Delta problems. It changed how water was managed and produced new practices that persisted until at least 2005. CALFED's collaborative approach is by nature informal, and it coexists uneasily with the norms and structure of formal government. This story illustrates how formal and informal systems are interdependent, yet in tension, across planning, participation, and decision making. Because planners often operate in the interface between the formal and the informal, the story offers lessons that can be applied at many levels of government and for many planning tasks. 相似文献
997.
Kaschin Jamal Jameel Willem-Jakob Gallert Sarah D. Yanik Susanne Panek Juliane Kronsbein David Jungck Andrea Koch Jürgen Knobloch 《International journal of molecular sciences》2021,22(13)
In smoking-induced chronic obstructive pulmonary disease (COPD), various comorbidities are linked to systemic inflammation and infection-induced exacerbations. The underlying mechanisms are unclear but might provide therapeutic targets. T-cell activity is central in systemic inflammation and for infection-defense mechanisms and might be influenced by comorbidities. Hypothesis: Circulating biomarkers of comorbidities modulate the activity of T-cells of the T-helper type 1 (Th1) and/or T-cytotoxic type 1 (Tc1). T-cells in peripheral blood mononuclear cells (PBMCs) from non-smokers (NS), current smokers without COPD (S), and COPD subjects (total n = 34) were ex vivo activated towards Th1/Tc1 and were then stimulated with biomarkers for metabolic and/or cardiovascular comorbidities (Brain Natriuretic Peptide, BNP; chemokine (C-C motif) ligand 18, CCL18; C-X3-C motif chemokine ligand 1, CX3CL1; interleukin-18, IL-18) or for asthma- and/or cancer-related comorbidities (CCL22; epidermal growth factor, EGF; IL-17; periostin) each at 10 or 50 ng/mL. The Th1/Tc1 activation markers interferon-γ (IFNγ), tumor necrosis factor-α (TNFα), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were analyzed in culture supernatants by Enzyme-Linked Immunosorbent Assay (ELISA). Ex-vivo activation induced IFNγ and TNFα without differences between the groups but GM-CSF more in S vs. NS. At 10 ng/mL, the different biomarkers increased or reduced the T-cell activation markers without a clear trend for one direction in the different categories of comorbidities or for the different T-cell activation markers. At 50 ng/mL, there was a clear shift towards suppressive effects, particularly for the asthma— and cancer-related biomarkers and in cells of S and COPD. Comorbidities might suppress T-cell immunity in COPD. This could explain the association of comorbidities with frequent exacerbations. 相似文献
998.
Leroy F Vankrunkelsven S De Greef J De Vuyst L 《International journal of food microbiology》2003,83(1):27-38
Bacteriocin production by Enterococcus faecium RZS C5 occurs in a growth-associated way but is generally switched off in the very early growth phase. The influence of environmental stress on the bacteriocin production kinetics by E. faecium RZS C5 was analysed at a controlled temperature of 35 degrees C and constant pH 6.5. The effect of environmental stress on bacteriocin production was depending on the type of stress applied. Oxidative stress did not interfere with cell growth or bacteriocin activity. In contrast, salt stress decreased both the cell growth and the specific bacteriocin production. Nevertheless, moderate levels of sodium chloride improved bacteriocin activity because they increased the biomass concentration at which bacteriocin production was switched off. Environmental stress due to limitations in sugar or complex nutrients did not affect the early shut-off mechanism or the specific bacteriocin production. However, bacteriocin stability decreased or increased at low levels of sugar or complex nutrients, respectively. 相似文献
999.
Sarah A. Castine Jessica R. Bogard Benoy K. Barman Manjurul Karim Md. Mokarrom Hossain Mrityunjoy Kunda A. B. M. Mahfuzul Haque Michael J. Phillips Shakuntala H. Thilsted 《Food Security》2017,9(4):785-801
In Bangladesh, homestead pond aquaculture currently comprises a polyculture of large fish species but provides an ideal environment to integrate a range of small fish species. Small fish consumed whole, with bones, head and eyes, are rich in micronutrients and are an integral part of diets, particularly for the poor. Results from three large projects demonstrate that the small fish, mola (Amblypharyngodon mola) contributes significantly to the micronutrients produced from all fish, in homestead ponds, in one production cycle. Mola contributed 98%, 56% and 35% of the total vitamin A, iron and zinc produced, respectively, despite comprising only 15% of the total fish production by weight. If consumed within the household, mola could contribute half of the vitamin A and a quarter of the iron intake recommended for a family of four, annually. Homestead ponds are uniquely accessible to women who prepare the household food. Further dissemination of the carp-small fish technology provides opportunities to target women and men together for training on fish production and consumption, nutrition and gender equity. Women only training is also recommended to enable them to engage fully, without feeling dominated by men. Partnering with the fisheries and health sectors will encourage sustainable uptake of this promising technology. Clearly, dissemination could have significant health benefits; however, improved monitoring and evaluation, particularly of dietary diversity and diet quality are essential. Research priorities should also include the production techniques of other small indigenous fish species (SIS), besides mola, and the power dynamics between women and men in operating homestead ponds. 相似文献
1000.
Incorporation of eicosapentaenioic and docosahexaenoic acids into breast adipose tissue of women at high risk of breast cancer: A randomized clinical trial of dietary fish and n‐3 fatty acid capsules 下载免费PDF全文