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101.
Hans-Ulrich Waiblinger Miriam Schillinger Norbert Hess 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(2):163-170
Here, we describe the procedure of a DNA extraction method from maize starch including the method??s validation by in-house and interlaboratory tests. The amplifiable amount of maize DNA tested by real-time PCR was used as parameter for evaluating our method. The practical (i.e. relative) limit of detection (LOD) was used as key criterion for assessing the suitability of the extraction method with respect to genetically modified organism analysis. In a round-robin test with ten participating laboratories, satisfactory results were achieved with practical LODs in the range of 0.1?% with three native maize starch materials. In-house tests showed that this protocol??with an additional purification step??can also be applied for extracting DNA from chemically or enzymatically modified starch. 相似文献
102.
The Suspicion of Simulation. A Psychiatric Case History between Appropriation and Disciplinary Action at the End of the 19th
Century.
This case history explores how the question of agency was dealt with historically in two developing, normative orders of deviant
behaviour. Examining the institutional career of the supposed adulterer, marriage swindler, and craft baker, we can trace
the different observation regimes and systems of knowledge acquisition in the prison and in psychiatry. In both institutions
there was talk of simulated madness; the explanations, however, were different. For the prison doctors and civil servants,
the baker was a criminal; his deviant behaviour was a matter of consciously planned-out deception. For the examining psychiatrist,
on the other hand, he was mentally ill and could not be held responsible for his own behaviour. 相似文献
103.
104.
Electrolytic Adamantylation by Reductive Coupling of Quinolinylhalides in the Presence of 1-Bromoadamantane Electrochemically generated anion radicals of a number of halogen-substituted quinolines 1 a–g dehalogenate in N,N-dimethylformamide to halogen anions and radicals, which may stabilize by hydrogen abstraction from the solvent. In the presence of 1-bromoadamantane the fragments of reductive dehalogenation may be used synthetically for indirect generation of 1-bromoadamantane-radicals, which react predominantly to cross-coupled 2- and 7-monoadamantylated dihydroquinoline- and quinoline-structures, independent of the original halogen position. If C-2 is blocked, adamantylation takes place in the carbocyclic ring. Product distribution and cyclic-voltammetric results are discussed in terms of mechanism. 相似文献
105.
106.
107.
Zimmerman Jeffrey; Hess Allen K.; McGarrah Nancy A.; Benjamin G. Andrew H.; Ally Glenn A.; Gollan Jackie K.; Kaser-Boyd Nancy 《Canadian Metallurgical Quarterly》2009,40(6):539
The provision of psychological (e.g., psychotherapy, coparenting, mediation, collaborative divorce, child custody evaluation) services for families of divorce are growing specialties for many clinical and forensic psychologists. However, practice in domestic relations psychology, such as divorce and custody assessment and testimony, is a high-risk venture for incurring ethics complaints and law suits. The lead article and the three commentaries that follow enumerate the various roles practitioners might play, clarify how each role requires specific skill sets that may be outside one’s particular competence and necessitate additional training, describe how countertransferential issues arise, urge meticulous record keeping, discuss some of the subtleties of confidentiality and the releasing of information, describe how transparency in clarifying expectations leads to a lowering of contentiousness, and provide tips for divorce and forensic practice. The special challenges associated with psychologists being tempted to move beyond their role on a case and those of particularly high-risk situations (e.g., complaints of child abuse or domestic violence) are also discussed. Suggestions are offered to help psychologists better serve the public while taking steps to better inoculate themselves from complaints. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
G. Xiong R. Shao S. J. Peppernick A. G. Joly K. M. Beck W. P. Hess M. Cai J. Duchene J. Y. Wang W. D. Wei 《JOM Journal of the Minerals, Metals and Materials Society》2010,62(12):90-93
Photoelectron emission microscopy (PEEM) is a versatile technique that can image a variety of materials including metals, semiconductors and even insulators. Under favorable conditions the most advanced aberration corrected instruments have a spatial resolution approaching 2 nm. Although PEEM cannot compete with transmission or scanning electron microscopies for ultimate resolution, the technique is much gentler and has the unique advantage of imaging structure as well as electronic and magnetic states on the nanoscale. Since the image contrast is derived from spatial variations in electron photoemission intensity, PEEM is ideal for interrogating both static and dynamic electronic properties of complex nanostructured materials. Here, we review the key principles and contrast mechanisms of PEEM and briefly summarize materials applications of PEEM. 相似文献
109.
110.
Sensitive photoacoustic detection of ammonia with near-infrared diode lasers (1.53 microns) and a novel differential acoustic resonator is described; a sensitivity of 0.2 parts per million volume (signal-to-noise ratio = 1) is attained. To eliminate adsorption-desorption processes of the polar NH3 molecules, a relatively high gas flow of 300 SCCM was used for the ammonia-nitrogen mixture. The results are compared with recent ammonia measurements with a NIR diode and absorption spectroscopy used for detection and photoacoustic experiments performed with an infrared quantum-cascade laser. The performance of the much simpler and more compact setup introduced here was comparable with these previous state-of-the-art measurements. 相似文献