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101.
In what ways can architectural design define identity, or alternatively, challenge received identity? Based on a design pedagogy that experiments with both defamiliarization and dance, we distinguish two ways: (1) in the readymade space of the eye, as meanings other than the received ones can emerge, or (2) in the space-in-the-making of the body, as the reading of meaning in ready-made space alone is challenged, and meaning also emerges in the order of our mutual movement with one another.
Our pedagogy represents a collaboration between an architect and a philosopher, both actively engaged in interdisciplinary education within and between their respective schools as well as with the School of Engineering. From the outset, we saw "design in movement" as a potential framework to foster side-by-side collaboration between disciplines (interdisciplinarity) rather than merely among disciplines (multidisciplinarity).
Design in movement is a complement to traditional architectural design in space. Design in movement allows us to experience, through our bodies, in a way that challenges our deeply ingrained visual culture. If we design in this visual culture without being able to call the culture into question, we do not take advantage of the full range of design's liberative potential: it is one thing to design so as to refuse any single authoritative reading in space, but another to discover an alternative to reading itself. We are investigating how design in movement can motivate new ways of liberative building and inhabiting that challenge the hegemony of design in space.  相似文献   
102.
The responses to fertiliser‐N of winter wheat and winter barley grown on sandy soils were measured in 72 experiments in England from 1990 to 1994. Yield without fertiliser‐N (Y0) was c 1.1 t ha−1 greater following root crops than following cereals. Following potato crops given organic manures, Y0 was c 1.2 t ha−1 greater than following unmanured potato crops, but Y0 was no greater following sugarbeet to which organic manures had been applied. Only after the two driest winters was there sufficient variation in soil N supply in spring (SNSs) for this to show a relationship with Y0. However, Y0 increased with increasing N mineralisation during the growing season (AM) in the three years it was measured. There was no consistent effect of sowing date on Y0. Following potatoes, yield at optimum fertiliser‐N (Yopt) decreased as sowing date was delayed, but this was not so after cereals, sugarbeet or overall. There was no increase in Yopt with SNSS or AM, but Yopt decreased with increasing moisture stress (S) in June. The mean yield response to NoptY) was c 0.4 and 0.8 t ha−1 smaller following potatoes and sugarbeet respectively than following cereals, but not consistently so as there were large interactions between site, year and previous crop. Following root crops, ΔY was c 0.6 and 1.4 t ha−1 less after sugarbeet and potatoes respectively that had been given organic manures. Without the addition of organic manures, ΔY following potatoes was similar to that following cereals. Regression on SNSS and AM accounted for 28 and 15% respectively of the variance in ΔY. The optimum economic fertiliser‐N application (Nopt) was similar, at c 140 kg ha−1, following cereals and potatoes. Following sugarbeet, cereal Nopt was only c 110 kg ha−1. The differences according to previous crop reported here are consistent with mineralisation of crop residues on sandy soils being more rapid than on other soils; the potato residues were rapidly mineralised in autumn and lost by leaching over winter. Residues from later‐harvested sugarbeet were mineralised during the growing season of the subsequent cereal crop. Fertiliser‐N requirements were, at c 110–140 kg ha−1, smaller than has been found on other soil types, and less than current recommendations for wheat. Requirements were significantly reduced in years of drought stress. No differences were found in Nopt between wheat and barley. These data do not justify the current advice to invariably reduce fertiliser‐N to cereals following potatoes by 20–25 kg ha−1 on these sandy soils. On average a reduction of c 20 kg ha−1 could be made following sugarbeet, with a further reduction of c 40 kg ha−1 N if manures had been applied to the previous sugarbeet crop. A reduction of 40 kg ha−1 N could also be made where cereals followed a potato crop to which manures had been applied. Further refinements on the basis of measurements of soil mineral N could not be justified. Seasonal variation in N response due to drought stress makes recommendations difficult on these soils. Adopting the fertiliser‐N recommendations proposed here would produce N surpluses to the soil of c 37, 10 and 27 kg ha−1 respectively following cereals, sugarbeet and potatoes when cereal grain is removed but straw incorporated. On farms where straw is removed, N surplus would be largely eliminated. Our recommendation that no reduction in fertiliser‐N application to cereal crops grown on sandy soils should be made following potatoes will not increase fertiliser‐N use and is not expected to increase nitrate leaching. Some reduction in nitrate leaching may be achieved if recommendations following cereal crops and sugarbeet are made in accordance with the results reported here. © 2000 Society of Chemical Industry  相似文献   
103.
Deoxynivalenol (DON), a mycotoxin produced by several Fusaruim species, is a worldwide contaminant of foods and feeds. Because of the potential dangers due to accidental or intentional contamination of foods with DON, there is a need to develop a rapid and highly sensitive method for easy identification and quantification of DON. In this study, we have developed and utilized a competitive immunoassay technique to detect DON in various food matrixes and indoor air samples using an array biosensor. A DON-biotin conjugate, immobilized on a NeutrAvidin-coated optical waveguide, competed with the DON in the sample for binding to fluorescently labeled DON monoclonal antibodies. To demonstrate a simple procedure amenable for on-site use, DON-spiked cornmeal, cornflakes, wheat, barley, and oats were extracted with methanol-water (3:1) and assayed without cleanup or preconcentration. The limits of detection ranged from 0.2 ng/mL in buffer to 50 ng/g in oats. The detection limit of DON spiked into an aqueous effluent from an air sampler was 4 ng/mL.  相似文献   
104.
The occurrence of different mycotoxins in cereal products calls for the development of a rapid, sensitive, and reliable detection method that is capable of analyzing samples for multiple toxins simultaneously. In this study, we report the development and application of a multiplexed competitive assay for the simultaneous detection of ochratoxin A (OTA) and deoxynivalenol (DON) in spiked barley, cornmeal, and wheat, as well as in naturally contaminated maize samples. Fluoroimmunoassays were performed with the Naval Research Laboratory array biosensor, by both a manual and an automated version of the system. This system employs evanescent-wave fluorescence excitation to probe binding events as they occur on the surface of a waveguide. Methanolic extracts of the samples were diluted threefold with buffer containing a mixture of fluorescent antibodies and were then passed over the arrays of mycotoxins immobilized on a waveguide. Fluorescent signals of the surface-bound antibody-antigen complexes decreased with increasing concentrations of free mycotoxins in the extract. After sample analysis was completed, surfaces were regenerated with 6 M guanidine hydrochloride in 50 mM glycine, pH 2.0. The limits of detection determined by the manual biosensor system were as follows: 1, 180, and 65 ng/g for DON and 1, 60, and 85 ng/g for OTA in cornmeal, wheat, and barley, respectively. The limits of detection in cornmeal determined with the automated array biosensor were 15 and 150 ng/g for OTA and DON, respectively.  相似文献   
105.
We constructed a library of beta-lactamases by recombining three naturally occurring homologs (TEM-1, PSE-4, SED-1) that share 34-42% sequence identity. Most chimeras created by recombining such distantly related proteins are unfolded due to unfavorable side-chain interactions that destabilize the folded structure. To enhance the fraction of properly folded chimeras, we designed the library using SCHEMA, a structure-guided approach to choosing the least disruptive crossover locations. Recombination at seven selected crossover positions generated 6561 chimeric sequences that differ from their closest parent at an average of 66 positions. Of 553 unique characterized chimeras, 111 (20%) retained beta-lactamase activity; the library contains hundreds more novel beta-lactamases. The functional chimeras share as little as 70% sequence identity with any known sequence and are characterized by low SCHEMA disruption (E) compared to the average nonfunctional chimera. Furthermore, many nonfunctional chimeras with low E are readily rescued by low error-rate random mutagenesis or by the introduction of a known stabilizing mutation (TEM-1 M182T). These results show that structure-guided recombination effectively generates a family of diverse, folded proteins even when the parents exhibit only 34% sequence identity. Furthermore, the fraction of sequences that encode folded and functional proteins can be enhanced by utilizing previously stabilized parental sequences.  相似文献   
106.
We demonstrate the observation and measurement of simple nanoscale devices over their complete lifecycle from creation to failure within a transmission electron microscope. Devices were formed by growing Si nanowires, using the vapor-liquid-solid method, to form bridges between Si cantilevers. We characterize the formation of the contact between the nanowire and the cantilever, showing that the nature of the connection depends on the flow of heat and electrical current during and after the moment of contact. We measure the electrical properties and high current failure characteristics of the resulting bridge devices in situ and relate these to the structure. We also describe processes to modify the contact and the nanowire surface after device formation. The technique we describe allows the direct analysis of the processes taking place during device formation and use, correlating specific nanoscale structural and electrical parameters on an individual device basis.  相似文献   
107.
A technique to study nanowire growth processes on locally heated microcantilevers in situ in a transmission electron microscope has been developed. The in situ observations allow the characterization of the nucleation process of silicon wires, as well as the measurement of growth rates of individual nanowires and the ability to observe the formation of nanowire bridges between separate cantilevers to form a complete nanowire device. How well the nanowires can be nucleated controllably on typical cantilever sidewalls is examined, and the measurements of nanowire growth rates are used to calibrate the cantilever‐heater parameters used in finite‐element models of cantilever heating profiles, useful for optimization of the design of devices requiring local growth.  相似文献   
108.
Objective: Despite proven efficacy of cognitive behavioral therapy (CBT) for treating eating disorders with binge eating as the core symptom, few patients receive CBT in clinical practice. Our blended efficacy–effectiveness study sought to evaluate whether a manual-based guided self-help form of CBT (CBT-GSH), delivered in 8 sessions in a health maintenance organization setting over a 12-week period by master's-level interventionists, is more effective than treatment as usual (TAU). Method: In all, 123 individuals (mean age = 37.2; 91.9% female, 96.7% non-Hispanic White) were randomized, including 10.6% with bulimia nervosa (BN), 48% with binge eating disorder (BED), and 41.4% with recurrent binge eating in the absence of BN or BED. Baseline, posttreatment, and 6- and 12-month follow-up data were used in intent-to-treat analyses. Results: At 12-month follow-up, CBT-GSH resulted in greater abstinence from binge eating (64.2%) than TAU (44.6%; number needed to treat = 5), as measured by the Eating Disorder Examination (EDE). Secondary outcomes reflected greater improvements in the CBT-GSH group in dietary restraint (d = 0.30); eating, shape, and weight concern (ds = 0.54, 1.01, 0.49, respectively; measured by the EDE Questionnaire); depression (d = 0.56; Beck Depression Inventory); and social adjustment (d = 0.58; Work and Social Adjustment Scale), but not weight change. Conclusions: CBT-GSH is a viable first-line treatment option for the majority of patients with recurrent binge eating who do not meet diagnostic criteria for BN or anorexia nervosa. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
Objective: Adoption of effective treatments for recurrent binge-eating disorders depends on the balance of costs and benefits. Using data from a recent randomized controlled trial, we conducted an incremental cost-effectiveness analysis (CEA) of a cognitive–behavioral therapy guided self-help intervention (CBT–GSH) to treat recurrent binge eating compared to treatment as usual (TAU). Method: Participants were 123 adult members of an HMO (mean age = 37.2 years, 91.9% female, 96.7% non-Hispanic White) who met criteria for eating disorders involving binge eating as measured by the Eating Disorder Examination (C. G. Fairburn & Z. Cooper, 1993). Participants were randomized either to treatment as usual (TAU) or to TAU plus CBT–GSH. The clinical outcomes were binge-free days and quality-adjusted life years (QALYs); total societal cost was estimated using costs to patients and the health plan and related costs. Results: Compared to those receiving TAU only, those who received TAU plus CBT–GSH experienced 25.2 more binge-free days and had lower total societal costs of $427 over 12 months following the intervention (incremental CEA ratio of ?$20.23 per binge-free day or ?$26,847 per QALY). Lower costs in the TAU plus CBT–GSH group were due to reduced use of TAU services in that group, resulting in lower net costs for the TAU plus CBT group despite the additional cost of CBT–GSH. Conclusions: Findings support CBT–GSH dissemination for recurrent binge-eating treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
This study examined the association of sociodemographic characteristics and smoking behaviors (i.e., cigarette, cigar, and waterpipe) with nicotine product harm perception in college freshmen. Students were asked to compare the perceived harmfulness of 11 nicotine-delivering products with that of a regular cigarette. Data were from a cross-sectional Internet survey conducted during the spring 2004 semester at a private university (N = 411). Binomial logistic regression was used to determine the association between sociodemographic and behavioral factors with nicotine product harm perception. A statistically significant association was found between nicotine product harm perception and sex, race, income, citizenship, and smoking behavior (p< or =.05). Regarding the three medicinal nicotine replacement therapies, 19.6% of respondents incorrectly perceived the nicotine patch to be as harmful as or more harmful than a regular cigarette; corresponding values were 24.1% for nicotine gum and 52.9% for nicotine inhaler. Respondents incorrectly perceived the following smoked tobacco products to be less harmful than regular cigarettes: ultra-light cigarettes (40.4%), waterpipe (37%), light cigarettes (35.2%), cigarillos (17.4%), and cigars (16.9%). Regarding smokeless nicotine products, 89.3% of respondents incorrectly perceived dip and chew to be as harmful as or more harmful than regular cigarettes; corresponding values were 36.2% for nicotine lollipops and 35.2% for nicotine water. Our findings reveal misperceptions about nicotine product harmfulness and underscore the importance of developing a science base to inform policies and educate consumers about these products.  相似文献   
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