Research subject selection

A decade later, in a published interview, Costill reflected on the diversity of subsequent research findings following this intial spate of positive results and he speculated that they may be related to subject selection variables. He felt that some people may be positive responders to caffeine, since in the first two studies his group conducted, several of the same subjects were employed.39... 

Methods and Experimental. In the study reported by Beecher et al. (17), nine men aged 23-39 years served as subjects. On the day prior to the initiation of the first experiment, the subjects selected their day s meals from a limited menu. The quantity and choice of foods were then repeated on each subsequent pre-experimental day. The subjects fasted overnight, voided upon rising and then drank 300 ml of water. Upon arrival at the research center (0730-0830 hrs), fasting blood was drawn and urine collected. The subjects then ingested one of the liquid meals and drank 200 ml of water. The subjects also drank 200 ml of water each 1/2 hour during the duration of the experiment to induce diuresis. Blood was drawn at 1/2, 1, 2, and 3 hours post-meal urine was collected at each 1/2 hour for 3 hours post-meal. Seven to 14 days elapsed between experiments. 

In 1976, Ueno and Okawara highlighted the fact that no oxidation of primary saturated alcohols to aldehydes via tin alkoxides had been reported in the literature and published a procedure for the selective oxidation of secondary alcohols.25 Interestingly, rather than performing the oxidation on pre-formed tin alkoxides, these researchers subjected a mixture of the diol and (Bu3Sn)20 in CH2C12 to the action of Br2. Regardless of the fact that no complete formation of tin alkoxides is secured and no HBr quencher is added, this method may provide useful yields of hydroxyketones during the selective oxidation of diols.26... 

Factors may have associated values called levels of variations. Each state of a black box has a definite combination of factor levels. The more different states of the black box that exist, the more complex is the research subject. Formalization of preliminary information includes analysis of reference data, expert opinions and use of direct data, which enables correct selection of response, factors and null point or center of experiment. Factor limitations are also defined at this stage. If the research is linked with several following responses, then response limitations also have to be analyzed. The next phase refers to defining the research problem. When defining this problem one must keep in mind the research-subject model, and in a general case it is Eq. (2.1) that defines the link between the inlet and outlet of the black box. Defining the research problem is possible only now when its aim has been determined, the criteria established, the factors, limitations and null point defined. The problem is a simple one when only one response or optimization criterion is in... 

Selection of the responses is one of the most important problems of a preliminary study of the research subject, since a correct definition of research objective means correct selection of the responses. An incorrect selection of the responses annuls all further research activities. Depending on the subject and research objective, optimization parameters or responses may be quite different. To formalize the procedure of selection of the responses, with no intention of being detailed and complete, Fig. 2.3 gives the block diagram of the most frequently used optimization parameters. 

When selecting a domain of factors one should pay special attention to choosing the center point of the design (basic level or the null point). The choice of a null point is associated with selection of the initial status of the research subject to perform optimization. As optimization is connected with improvement of the subject status in comparison with the status in the null point, it is desirable that the point is in the optimum region or as close to it as possible. If the mentioned research was preceded by other experiments on the same subject, the status having the most convenient response value is taken as the null experiment. The null point is quite often the center of the domain of factors. The most important alternatives in selecting the basic and null levels are shown in Fig. 2.10. 

It is important once again to note that, when considering factors, all variables having the least possible chance to affect the research subject are included. It is better in such a situation to include more factors, for the nonessential ones will be rejected in the process of selection. An example of defining factors is shown in Table 2.9 ... 

From the total number of noted factors, the researcher chooses those that may be varied during the experiment while he keeps the others at constant levels. When the number of selected factors is more than seven, a possibility of doing the screening experiments has to be considered. For a relatively small number of factors, an experiment is done to reach the optimum or to obtain the mathematical model of the research subject, depending on what the objective of the researcher s problem is. 

From the vast number of published papers dealing with solvent effects in all areas of organic chemistry, only some illustrative examples from the didactic and systematic point of view could be selected. This book is not a monograph covering all relevant literature in this field of research. The author, responsible for this subjective selection, apologizes in advance to all chemists whose valuable work on solvent effects is not mentioned in this book. However, using the reviews cited, the reader will find easy access to the full range of papers published in a certain field of research on solvent effects. 

Legislation that ensures the protection of human research subjects in the United States includes the 1979 publication of the Belmont Report on the Ethical Principles and Guidelines for the Protection of Human Subjects of Research.f This report concerns the fine line between biomedical research and the routine practice of medicine and explores the criteria that determine the risk-benefit ratio in the consideration of conducting clinical research. It also addresses basic guidelines for the proper selection of human research subjects and further defines the elements of informed consent. 

Several years ago one of the important research subjects in catalytic engineering—correlation among the methods of preparation of solid catalysts and their physical and chemical structures and their selective activities—had scarcely been reported. Therefore, in 1954 we started a systematic study along this line and since then have received the continuous collaboration of many researchers in other institutes. 

The selection of research subjects needs to be scrutinized in order to determine whether some classes (e.g., welfare patients, particular racial and ethnic minorities, or persons confined to institutions) are being systematically selected simply because of their easy availability, their compromised position, or their manipulability, rather than for reasons directly related to the problem being studied. Finally, whenever research supported by public funds leads to the development of therapeutic devices and procedures, justice demands both that these not provide advantages only to those who can afford them and that such research should not unduly involve persons from groups unlikely to be among the beneficiaries of subsequent applications of the research. 

Research with new medical devices must be carefully evaluated to ensure free and informed consent can be obtained. REBs must aid researchers to prevent conflicts of interest. This could be concerning subject selection or... 

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