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111.
A pair of degenerate primers was used for amplification and cloning of a DNA fragment containing parts of the P. pastoris URA5 and SEC65 genes. Using additional information from a partial genomic sequence of P. pastoris, we cloned and sequenced a 1.9 kb chromosomal fragment containing the complete orotate-phosphoribosyltransferase-encoding URA5 gene. A disruption cassette was constructed by replacing a small part of the open reading frame with a kanamycin-resistance gene. The P. pastoris wild-type strain NRRL Y-11430 was transformed with the disruption cassette and an ura5 auxotrophic strain was identified. To generate marker constructs that can be reused in successive transformations of a single strain, we constructed two lacZ-PpURA3-lacZ and lacZ-PpURA5-lacZ cassettes and used them to disrupt PpOCH1. The PpURA3 and PpURA5 genes in the disruptants were then successfully recycled by selecting for resistance to 5'-fluoro-orotic acid. We also assembled a set of modular plasmids that can be used for the stable genetic modification of P. pastoris via a double cross-over event. The sequence presented here has been submitted to the EMBL data library under Accession No. AY303544. 相似文献
112.
Dorothy E. Fenwick David Oakenfull 《Journal of the science of food and agriculture》1983,34(2):186-191
Quantitative thin layer chromatography was used to estimate the saponin content of 20 common food plants and also of foods prepared from some of them. The food plants found to be richest in saponins were chickpeas (Cicer arietinum), soya beans (Glycine max), lucerne (alfalfa) sprouts (Medicago sativa) and varieties of Phaseolus vulgaris (navy beans, haricot beans, kidney beans). Saponins were not destroyed by processing or cooking. They were present in falafels (prepared from chickpeas), canned baked beans, canned broad beans and protein isolate from faba beans. However, the saponin content of a fermented soya bean product (tempe) was only half that of whole soya beans. Guar meal (Cyamopsis tetragonolobus) contains saponins but only a trace could be detected in samples of guar gum. 相似文献
113.
Abstract Southern pine and aspen flakes were acetylated with acetic anhydride alone without cosolvent or catalyst by a simple dip procedure. The new procedure greatly shortens reaction time and simplifies chemical recovery. Acetylation weight gains of 15% to 20% can be achieved in 1 to 3 hours with southern pine flakes and in 2 to 4 hours with aspen flakes. Flakeboards made from acetylated southern pine or aspen flakes absorbed much less water, both in water-soaking tests and when subjected to humid air, and swelled at a lower rate and to a lower extent than did control boards. Hygroscopicity of the resulting flakeboards decreased with increased level of wood acetylation. The equilibrium moisture content (EMC) for flakeboards made from acetylated flakes was lower at each relative humidity tested than that of control boards. 相似文献
114.
Hatsukami Dorothy; LaBounty Lynda; Hughes John; Laine Dawn 《Canadian Metallurgical Quarterly》1993,12(6):499
The total caloric and specific nutrient intakes of smokers who became abstinent were compared with those of a control group. Both groups were composed of volunteer inpatients housed in a research ward for 7 days. After smoking ad libitum for 3 days, the experimental group was required to abstain from tobacco for the next 4 days while the control group continued to smoke. Significant increases in total caloric intake and in grams of carbohydrates, protein, fat, and sucrose were observed in the experimental relative to the control group, whereas no significant differences were found in fructose intake. The increase in caloric intake was not specific to increases in snacking. Preliminary analyses showed gender differences in food intake as a result of tobacco abstinence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
Wenyu Du Shan L. Pan Dorothy E. Leidner Wenchi Ying 《The Journal of Strategic Information Systems》2019,28(1):50-65
Blockchain, the technology underlying bitcoin, is an emerging financial technology (FinTech) that is poised to have strategic impacts on organizations. Because it is a new phenomenon, there are few studies on blockchain, and those studies have focused mainly on the technology’s potential impacts, whereas how to effectively implement it in an organization remains unknown. Our study intends to fill that gap. Using affordance-actualization (A-A) theory as the theoretical lens, we conducted a case study of blockchain implementation in an organization that has effectively implemented it. We identify three affordances of blockchain in the organization and a process model whereby these affordances are actualized. The process model extends A-A theory by adding an experimentation phase where blockchain’s use cases within the organization are identified, developed and tested through conceptual adaptation and constraint mitigation. Our study makes important theoretical contributions to the literature on A-A theory, blockchain, information technology (IT) implementation, and strategic information systems (SIS). Our study can also help IT practitioners to implement blockchain effectively and extract value from their investment. 相似文献
116.
P. Sorn-Srivichai J. K. Syers R. W. Tillman I. S. Cornforth 《Nutrient Cycling in Agroecosystems》1988,15(3):211-223
A water extraction procedure was evaluated as a soil-testing procedure for phosphorus (P). In a glasshouse experiment using perennial ryegrass, the water extraction procedure was used to predict plant-available P in 20 New Zealand soils varying widely in P status and P retention capacity. Water-extractable P in the 20 soils was highly correlated with plant uptake of P (r = 0.90**). Although plant uptake of P and Olsen-extractable P were equally well correlated (r = 0.90**), relationships between plant uptake of P and Bray1 — and Truog-extractable P, and isotopically exchangeable P were less close. The prediction of plant-available P using water extraction was not improved by inclusion of an estimate of P-buffering capacity (obtained from P retention capacity or the slope of the P desorption isotherm), in contrast to the finding for Olsen-extractable P. Because the interpretation of the results obtained appears to be independent of P-buffering capacity and soil type, the water extraction procedure may have advantages over the other soil-testing procedures for P for soils containing reasonable amounts of water-extractable P. 相似文献
117.
Kagehiro Dorothy K.; Mejia Juan A.; Garcia Joseph E. 《Canadian Metallurgical Quarterly》1985,16(4):481
Argues that the limited generalizability of psychological theories and hypotheses may stem, in part, from a restricted sampling of psychological theorists and investigators and hence from the homogeneity of their background assumptions, biases, and values. Threats to generalizability at the hypothesis-testing, theory-development, and hypothesis-formation stages of research are discussed using examples from the literature. A cultural pluralism approach is recommended for the recruitment and training of socioculturally diverse psychologists, capable of conducting research in a wider variety of settings with a wider range of Ss. Types of short- and long-term location and recruitment techniques are discussed, and the promotion of the cultural pluralism perspective within the graduate curriculum is addressed. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Espelage Dorothy L.; Mazzeo Suzanne E.; Aggen Steven H.; Quittner Alexandra L.; Sherman Roberta; Thompson Ron 《Canadian Metallurgical Quarterly》2003,15(1):71
The construct validity of the Eating Disorder Inventory (EDI) was examined in 3 samples. An archival clinic sample (n=318) of women completed the EDI, a structured interview, and the Millon Clinical Multiaxial Inventory--II (MCMI-II). Confirmatory factor analyses (CFAs) indicated that neither null nor 1-factor models of the EDI fit item-level or item-parcel data. The proposed 8-factor model did not fit at the item level but did fit item-parcel data. Reliability estimates of the 8 scales ranged from .82 to .93, and low-to-moderate interscale correlations among the eating and weight-related scales provided partial support for convergent validity. EDI personality scales showed moderate interscale correlations and were associated with MCMI-II scales. A final CFA of the EDI scales supported a 2-factor model (Eating and Weight, Personality) of the 8 EDI scales. Strong associations between depression and several EDI scale scores were found in a treatment study sample (n=50). The archival clinic sample scored significantly higher on the 8 EDI scales than the nonpatient college comparison sample (n=487). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
K Tillman JL Oberfield XQ Shen A Bubulya L Shemshedini 《Canadian Metallurgical Quarterly》1998,9(2):193-200
We assessed the possible association between an aggressive intercondylar notchplasty and histopathologic, radiographic, and gait changes to the knee. Three groups of six adult greyhounds were observed for 6 months. Group I dogs had a sham operation. Group II dogs had a 4-mm notchplasty of the lateral femoral condyle where it articulates with the lateral tibial spine. Group III dogs had a 7- to 8-mm notchplasty of the lateral femoral condyle to simulate the long-term effects of an overly aggressive notchplasty. Force plate gait analyses were not significantly different for any dogs at 3 and 6 months. Histopathologic studies (hematoxylin and eosin and safranin O stains) revealed notchplasty area remodeling with a thin layer of lamellar bone covered by fibrous connective tissue. Both Group II and III dogs had significant loss of lateral femoral condyle and trochlear groove articular surface proteoglycans. The radiographic notch width index remained unchanged throughout the study for Group I; the indexes increased immediately after surgery in Groups II and III because of the notchplasty, but after 6 months these values returned to near-preoperative measurements. An aggressive intercondylar notchplasty caused articular cartilage histopathologic changes at 6 months consistent with those found in knees with early degenerative arthritis. Significant refilling of a non-impinged notchplasty occurred by 6 months after surgery. Our results raise concern about the effects of aggressive intercondylar notch widening in humans. 相似文献
120.