Experimentally determined proton dissociation (and reassociation) rate constants for substituted naphthols in the first excited singlet state are reported. The results are rationalized on the basis of a charge-transfer explanation supported by CNDO/2 and PPP molecular orbital calculations.

In response to public concerns about the consequences of research misconduct, academic institutions have become increasingly cognizant of the need to implement comprehensive, effective training in the responsible conduct of research (RCR) for faculty, staff, students, and external collaborators. The ability to meet this imperative is challenging as universities confront declining financial resources and increasing complexity of the research enterprise. The authors describe the University of Pittsburgh's design, implementation, and evaluation of a Web-based, institution-wide RCR training program called Research and Practice Fundamentals (RPF). This project, established in 2000, was embedded in the philosophy, organizational structure, and technology developed through the Integrated Advanced Information Management Systems grant from the National Library of Medicine. Utilizing a centralized, comprehensive approach, the RPF system provides an efficient mechanism for deploying content to a large, diverse cohort of learners and supports the needs of research administrators by providing access to information about who has successfully completed the training. During its first 3 years of operation, the RPF served over 17,000 users and issued more than 38,000 training certificates. The 18 modules that are currently available address issues required by regulatory mandates and other content areas important to the research community. RPF users report high levels of satisfaction with content and ease of using the system. Future efforts must explore methods to integrate non-RCR education and training into a centralized, cohesive structure. The University of Pittsburgh's experience with the RPF demonstrates the importance of developing an infrastructure for training that is comprehensive, scalable, reliable, centralized, affordable, and sustainable.

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Three independent methods have been used to determine the size of the quantum accumulation unit in green plant photosynthesis. This unit is defined as that group of pigment molecules within which quantal absorption acts must take place leading to the evolution of a single O(2) molecule. All three methods take advantage of the nonlinearity of oxygen yield with light dose at very low dosages. The experimental values of this unit size, based on an assumed model for the charge cooperation in O(2) evolution, ranging from 800 to 1600, suggest that there is either limited energy transfer between energy-trapping units or chemical cooperation among oxygen precursors formed in several neighboring energy-trapping units. Widely diffusible essential precursors to molecular oxygen are ruled out by these results. Inhibition studies show that O(2) evolution is blocked when 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) is added to chloroplasts after two preliminary flashes and before a third flash which would have yielded O(2) in the absence of DCMU. This experiment is interpreted as evidence that the site of DCMU inhibition is on the oxidizing side of system II. Pretreatment of chloroplasts with large concentrations of Tris, previously believed to destroy O(2) evolution by blocking an essential reaction in the electron chain between water and system II, may be alternately interpreted as promoting the dark reversal of the system II light-induced electron transfer.