Investigative site types

In the field of nucleophilic additions, Queguiner and co-workers investigated Michael-type additions onto quinoxalotropones like 376 (Schemes 100 and 101 83CJC1806) whose electrophilic sites are C-6, C-10, and C-8. The reactions lead to 1,4-monoaddition products or to bridged compounds resulting from bis-1,4-addition reactions ... 

Additional experiments were aimed at investigating other Ti-electron-rich site types that might prove suitable for incorporation into systems capable of undergoing controlled switching. Thus both benzidine 34 and 4,4 -biphenol 35 were demonstrated to form stable host-guest complexes in acetonitrile with the eyclo-bis(paraquat-/7-phenylene) tetracation. Although these hosts are structurally related, they have different redox properties, with 34 being much more readily oxidised than 35. 

Not all clinical trials, especially large, multisite, multinational phase III studies and phase IV postmarketing surveillance, pharmacoeconomic, and quality-of-life studies, can be conducted at a CSO facility. These types of studies, and many phase II efficacy studies, are conducted in research- or university-based hospitals or other investigational sites where a sufficient patient population with the disease or disorder to be tested is available. A number of CSOs offer services to support clinical trial studies that are implemented at one or more clinical trial sites. These services can be broken down into relatively broad categories, which are summarized later. 

Investigator site audits are probably the most frequent type of audits conducted by clinical QA departments and, therefore, deserve particular attention. The purpose of investigator site audits is to assess compliance with the GCP regulations (with a focus on the country-specific regulatory requirements) and the protocol. Further, thesafety of the trial participants, the ethical conduct of the trial and the validity, completeness and accuracy of the data collected and recorded are verified during the audit. 

The last decade of the twentieth century has been revolutionary in the study of molecular electron transfer processes. For the preceding century scientists have investigated three types of such processes transfer between a donor and an acceptor species, transfer between two sites on the same molecule and transfer between a molecular species in solution and a metal or a semiconductor electrode. The main observable in such studies is the electron transfer rate, though in studies of photoinduced electron transfer processes the quantum yield, defined as the number of electrons transfeiTed per photon absorbed, is also a useful observable. The invention of the tunneling microscope and later experimental developments have now made it possible to investigate another manifestation of electron transfer electronic conduction by a molecule connecting two bulk metal or semiconductor electrodes. In this... 

Sanders-Loehr, J. Investigation of Type I copper site geometry by spectroscopy and molecular redesign. In Bioinorganic Chemistry of Copper Karlin, K. D. Tyeklar, Z., Eds. Chapman and Hall New York, 1993 pp 51-63. Andrew, C. R. Sanders-Loehr, J. Acc. Chem. Res. 1996, 29, 365-372. 

Rhus vernicifera laccase is known to incorporate four tightly bound copper atoms distributed in three distinct sites. Type 1 copper is responsible for the intense blue colouration, and a second form of metal ion, type 2, is not associated with any specific spectroscopic absorption bands but has been inferred from e.s.r. studies. This centre is known to function as a strong anion-binding site. Type 3 copper is non-detectable by e.s.r. and is characterized by a u.v. absorption band (Amax ca. 330 nm). Anaerobic stopped-flow studies with hydroquinone (HgQ) have been made to investigate the mode of reduction at these centres. The type 1 and type 3 copper ions are reduced in parallel at comparable rates over a wide range of substrate concentrations and pH. The rate data are consistent with the mechanism... 

The paper presents the results from systematic comparisons of contrast and resolution obtained with different types of radiation sources on steel thicknesses from 5 to 40 mm. These results have been taken into account with the definitions of the European standard for radiographic inspection of weldments (EN 1435) that is approved since 1997. Conclusions from practical investigations on pipe line sites, in petrochcemical plants and in nuclear power stations will be discussed as well. Furthermore, the presentation will stipulate a variety of advantages obtained from the new source in terras of coUimation and radiation protection. 

Investigating a site is to first look at the type of soil and its bearing capacity. This should be done by digging boreholes at several designated locations over the entire landfill design site. There are several parameters which should be evaluated on the soil and they are ... 

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