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91.
Over the past decade, there has been increasing interest in the use of grounded theory in information systems research. Grounded theory is a qualitative research method that seeks to develop theory that is grounded in data systematically gathered and analysed. The purpose of this paper is to suggest guidelines for grounded theory studies in information systems. Our guidelines are based on a framework for theorizing in grounded theory studies that focuses on conceptualization and theory scope. Our hope is that the guidelines will help to raise the quality and aspirations of grounded theory studies in information systems. 相似文献
92.
93.
Elevated production of the aromatic fragrance molecule, 2‐phenylethanol,using Metschnikowia pulcherrima through both de novo and ex novo conversion in batch and continuous modes
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Tanakorn Chantasuban Fabio Santomauro Deborah Gore‐Lloyd Sophie Parsons Daniel Henk Roderick J Scott Christopher Chuck 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2018,93(8):2118-2130
BACKGROUND
2‐phenylethanol (2PE) is a fragrance molecule predominantly used in perfumes and the food industry. It can be made from petrochemicals inexpensively, however, this is unsuitable for most food applications. Currently, the main method of production for the bio‐derived compound is to extract the trace amounts found in rose petals, which is extremely costly. Potentially fermentation could provide an inexpensive, naturally sourced, alternative.RESULTS
In this investigation, 2PE was produced from the yeast Metschnikowia pulcherrima, optimised in flasks before scaling to 2 L batch and continuous operation. 2PE can be produced in high titres under de novo process conditions with up to 1500 mg L?1 achieved in a 2 L stirred bioreactor. This is the highest reported de novo titre to date, and achieved through high sugar loadings coupled with low nitrogen conditions. The process successfully ran in continuous mode also, with a concentration of 650 mg L?1 of 2PE being maintained. The 2PE production was further increased by the ex novo conversion of phenylalanine and semi‐continuous solid phase extraction from the supernatant. Under optimal conditions 14 000 mg L?1 of 2PE was produced.CONCLUSIONS
The work presented here offers a novel route to naturally sourced 2PE through a scalable fermentation with a robust yeast highly suited to industrial biotechnology. © 2018 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.94.
Tetrahydrodipicolinate (THDP) N-succinyltransferase catalyzes the conversion of tetrahydrodipicolinate and succinyl-CoA to L-2-(succinylamino)-6-oxopimelate and CoA. This reaction represents the committed step of the succinylase branch of the diaminopimelate/L-lysine biosynthetic pathway by which many bacteria synthesize meso-diaminopimelate, a component of peptidoglycan, and L-lysine from L-aspartate. The crystal structures of THDP succinyltransferase in complex with the substrate/cofactor pairs L-2-aminopimelate/coenzyme A and L-2-amino-6-oxopimelate/coenzyme A have been determined and refined to 2.0 A resolution. The active site of the enzyme is a long narrow groove located at the interface between two left-handed parallel beta-helix (LbetaH) structural domains of the trimeric enzyme. On binding the amino acid acceptor and cofactor, this groove is covered by residues from the C-terminus of one subunit and a flexible loop excluded from the LbetaH domain of an adjacent subunit to form a tunnel. This conformational change is directly related to interactions between the enzyme and the bound amino acid substrate and cofactor and serves to shield the ligands from bulk solvent and to orient the nucleophilic amino group of the amino acid acceptor toward the mercaptoethylamine group of the cofactor. 相似文献
95.
A twin study of cognitive function in chronic fatigue syndrome: The effects of sudden illness onset.
Claypoole Keith H.; Noonan Carolyn; Mahurin Roderick K.; Goldberg Jack; Erickson Tom; Buchwald Dedra 《Canadian Metallurgical Quarterly》2007,21(4):507
Variable reports of neuropsychological deficits in individuals with chronic fatigue syndrome (CFS) may, in part, be attributable to methodological limitations. In this study, these limitations were addressed by controlling for genetic and environmental influences and by assessing the effects of comorbid depression and mode of illness onset. Specifically, the researchers conducted a co-twin control study of 22 pairs of monozygotic twins, in which 1 twin met strict criteria for CFS and the co-twin was healthy. Twins underwent a structured psychiatric interview and comprehensive neuropsychological assessment evaluating 6 cognitive domains. Results indicated that twin groups had similar intellectual and visual memory functioning, but fatigued twins exhibited decreases in motor functions (p = .05), speed of information processing (p = .02), verbal memory (p = .02), and executive functioning (p = .01). Major depression did not affect neuropsychological functioning among fatigued twins, although twins with sudden illness onset demonstrated slowed information processing compared with those with gradual onset (p = .01). Sudden onset CFS was associated with reduced speed of information processing. If confirmed, these findings suggest the need to distinguish illness onset in future CFS studies and may have implications for treatment, cognitive rehabilitation, and disability determination. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
CB Xue J Roderick S Mousa RE Olson WF DeGrado 《Canadian Metallurgical Quarterly》1998,8(24):3499-3504
Despite the excellent in vitro potency of a series of benzamide glycoprotein IIb/IIIa antagonists, which have been reported previously, poor in vivo potency in the inhibition of platelet aggregation was observed when the most potent inhibitor XU057 was dosed intravenously to dogs. In this communication, we report that replacement of the benzamide in XU057 with an isoxazolecarboxamide resulted in significant improvement in in vivo potency. More importantly, the analogue XU065 showed an excellent oral antiplatelet effect in dogs. 相似文献
97.
98.
Psychological tests, especially the Minnesota Multiphasic Personality Inventory, became the center of public controversy and Congressional scrutiny during the 1960s. This unwanted attention actually helped American psychologists more than they imagined. Assisted by those on Capitol Hill, psychologists were able to defend their science in a manner that avoided imposed forms of public accountability. Social questions were reformulated as technical problems. The need to adjust intelligence and aptitude tests reinforced psychologists' control over them. Conversely, personality tests were not made more transparent and nonintrusive, unless psychologists thought these changes were scientifically necessary. This episode prompted tighter regulation of test use and demonstrated that traditional forms of testing were far too important to popularize and "give away." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Roderick J. Weston 《Journal of the science of food and agriculture》1983,34(9):1005-1010
The nitrosamine content of 16 New Zealand beers and one Australian beer, all manufactured in 1980, was determined by chemiluminescence. The levels, calculated as N-nitrosodimethylamine (NDMA) ranged from 0.2–1.8 μg dm?3 with a mean of 0.76 μg dm?3. Over a period of 2 years, the NDMA levels in New Zealand malt have been reduced as the result of changes in kilning technology, introduced to control the level of nitrogen oxides in kiln air. For example, the mean value for directly-fired malt was 5.4 μg kg?1, that for malt dried in air heated by burners to which sulphur had been added was 2.4 μg kg?1 and that for malt dried in air to which SO2 had been released was 0.3 μg kg?1. For the purposes of quality control, screening beer or malt for nitrosamines can be accomplished adequately by the injection of CH2Cl2 extracts directly into a thermal energy analyser. 相似文献
100.
Roderick J Lawrence 《Design Studies》1982,3(2):97-103
This paper looks at developments in architecural design techniques over the past few decades. It challenges some recurring assertions about participatory design in architecture. In particular, it responds to a critical debate at the Design Research Society conference held at Portsmouth (UK) in December 1980, by suggesting that if participatory design methods have shortcomings these should not automatically be levelled at the tenets of public participation, but primarily at the means currently employed to involve building users int he architectural design process. In conclusion, a redefinition and a diversification of participatory architectural design methods in suggested. 相似文献