Scientific information, evaluating

In this chapter we have attempted to summarize and evaluate scientific information available in the relatively young field of microwave photoelectrochemistry. This discipline combines photoelectrochemical techniques with potential-dependent microwave conductivity measurements and succeeds in better characterizing the behavior ofphotoinduced charge carrier reactions in photoelectrochemical mechanisms. By combining photoelectrochemical measurements with microwave conductivity measurements, it is possible to obtain direct access to the measurement of interfacial rate constants. This is new for photoelectrochemistry and promises better insight into the mechanisms of photogenerated charge carriers in semiconductor electrodes. 

CICADs are concise documents that provide summaries of the relevant scientific information concerning the potential effects of chemicals upon human health and/or the environment. They are usually based on selected national or regional evaluation documents or on existing EHCs. Before acceptance for publication as CICADs by IPCS, these documents undergo extensive peer review by internationally selected experts to ensure their completeness, accuracy in the way in which the original data are represented, and the validity of the conclusions drawn. 

We can now proceed to demonstrate how scientific information and the regulatory defaults of Table 8.2 can be applied. It is useful and important to separate the dose-response evaluations into those used for substances that produce their toxic effects through threshold mechanisms, as these terms were described or used in Chapters 3 and 6, and those that may involve no-threshold mechanisms. As a practical matter, only carcinogens have, to date, been treated as belonging in the latter category. 

As it had argued successfully in Upjohn v. Finch, the FDA needed something more scientific than personal accounts from patients and physicians to validate a drug s effectiveness. Informal evaluation by patients and doctors is subject to placebo effects (placebo is Latin for I will please ). Originally, a placebo referred to a harmless substance given to please a patient complaining about symptoms that otherwise could not be treated. The belief of the... 

EFSA is the newly established scientific body of the EU that provides objective scientific information and evaluations on all food safety issues, including food additives. EFSA is an independent European agency located in Parma, Italy, which provides risk assessments to the European Commission, European Parliament, and Council and operates various scientific panels including the panel on food additives, flavorings, processing aids, and materials in contact with food. 

Risk assessment The evaluation of scientific information on the hazardous properties of environmental agents (hazard characterization), the dose-response relationship (dose-response assessment), and the extent of human exposure to those agents (exposure assessment). 

Risk characterization The synthesis of critically evaluated information and data from exposure assessment, hazard identification, and dose-response considerations into a summary that identifies clearly the strengths and weaknesses of the database, the criteria applied to evaluation and validation of all aspects of methodology, and the conclusions reached from the review of scientific information. 

In a sense, we can say we have developed a system to assess environmental risk situations and are responding to those assessments with decisions reached in a deliberate and disciplined manner. The confidence we have in the system is built on the premise that we know it is directionally correct with its overall objective being to reduce risks. Moreover, the response decisions called for in the process result from evaluating all the available scientific information along with all the pertinent values and judgments that can be brought to bear. 

Bases health care services on consistent application of the best scientific information available on treatment and evaluation of care, with constant updating and improvement through use of quality improvement techniques. 

Three new publications are currently being evaluated for their usefulness in locating new published literature which has not yet appeared in the abstract journals and review articles abstracted in Chemical Abstracts Chemical Titles, Bibliography of Chemical Reviews, and Index Chemicus. The first two are new services provided by Chemical Abstracts and it is hoped that they will bridge the gap between the publication date of an article and the appearance of the corresponding annual index of Chemical Abstracts by means of which the abstract of the original article may be found in Chemical Abstracts. Index Chemicus is a compilation of new compounds disclosed in the current literature and the corresponding references. This new journal is published by the Institute of Scientific Information, Philadelphia, Pa. 

California Environmental Protection Agency s (Cal/EPA) Office of Environmental Health Hazard Assessment (OEHHA) administers the Proposition 65 program. OEHHA also evaluates all currently available scientific information on substances considered for placement on the Proposition 65 list. 

There are three principal ways for a chemical to be added to the Proposition 65 list. A chemical can be listed if either of two independent committees of scientists and health professionals finds that the chemical has been clearly shown to cause cancer or birth defects or other reproductive harm. These two committees are the Carcinogen Identification Committee (CIC) and the Developmental and Reproductive Toxicant (DART) Identification Committee, and both are part of OEHHA s Science Advisory Board. The committee members are appointed by the Governor and are designated as the State s Qualified Experts for evaluating chemicals under Proposition 65. When determining whether a chemical should be placed on the list, the committees base their decisions on the most current scientific information available. OEH-HA staff scientists compile all relevant scientific evidence on various chemicals for the committees to review. The committees also consider comments from the public before making their decisions. 

HEI. 1987. Gasoline vapor exposure and human cancer Evaluation of existing scientific information and recommendations for future research. Report of the Institutes Health Review Committee, September 1985. Health Effects Institute. Cambridge, MA. 17-47. 

Risk assessment might be viewed simply as a means of organizing and analyzing all available scientific information that bears on the question at hand. If we are interested in understanding the nature and size of the health risk associated with, for example, aflatoxin in peanut products or trichloroethylene in drinking water, there are three types of information that must be evaluated. 

The most valuable assessment of a base stock is how it performs in use as a formulated product and how well it meets the expectations of the formulator and the customer. The answer to this in the real world is complex, since many factors (application, specific conditions of use, price, availability, etc.) are involved. There are a number of standardized tests that provide comparative information under controlled conditions. For the most part, these tests employ inhibited base stock samples (i.e., those containing antioxidants). Perhaps most importantly, these tests are evaluations of the base stock s response to antioxidants, which is the result the formulator really wants and needs. These tests have also been used successfully to provide scientific information on the effects of base stock composition. This approach, coupled with advances in analytical technology, has been particularly successful when applied to the developing field of hydrocracked base stocks, which began in the 1970s. These stocks differ from solvent refined ones in having only very low levels of aromatics, sulfur, and nitrogen, so the focus was much more on hydrocarbon composition itself. 

Medicinal plants, plants used for eating purposes and other natural products, are mainly complex products with several components with different chemical and pharmacological characteristics. In addition, many of these products are also sold as dietary supplements, but scientific information about their safe and effective use is hard to find because limited toxicological data are available on herbal remedies and the support of rigorous clinical studies is lacking. A few reports of the toxicological evaluation in Baccharis species are available. 

Human Selenium Requirements and Recommended Dietary Intakes All intake recommendations depend on the definitions used to derive them and the available scientific information. Accordingly, they are not to be considered final as they are periodically re-evaluated and revised. 

Publication is at the core of every scientific endeavor. It is the common process whereby scientific information is reviewed, evaluated, distributed, and entered into the permanent record of scientific progress. Publications serve as vital links between factual databases of different structures or content domains (e.g., a record in a sequence database and a record in a genetic database may cite the same article). They serve as valuable entry points into factual databases ( I have read an article about this, now I want to see the primary data ). 

Lectures Research methodology, critical evaluation of scientific information, information literacy, writing scientific papers... 

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