Subject groups

With the advent of on-line searching in the 1970s, the Derwent file was one of the first to go on-line. It had subject retrieval capabiUty by the manual and punch code systems, tide terms, IPC, and broad subject groupings called Derwent classes, whose primary function had been to allocate patents to appropriate segments of the Derwent system. By 1981, abstracts were added to the database, after which abstracts for the entire back-file were added. 

Special Subjects Group 1-1 Namiki Tsukuba 305-0044 Japan... 

For example, if one were studying an herb to treat depression, one would want to control as many factors as possible that could influence the outcome. People already taking an antidepressant drug would have to be excluded. One might also balance the subjects in different groups for severity of depression, psychotherapy treatment, or even levels of physical exercise. Certainly, the subject groups should be balanced for number of males and females, because sex differences in depression could contaminate the results. 

Adult male volunteers were exposed to purified air,2 -2 - to ozone alone, or to ozone in combination with nitrogen dioxide and carbon monoxide. No additional effects were detected when nitrogen dioxide at 0.3 ppm was added to ozone. The addition of carbon monoxide at 30 ppm to the ozone-nitrogen dioxide mixture produced no additional effects, other than a slight increase in blood carboxyhemoglobin content and small decreases in psychomotor performance, which were not consistent in different subject groups. 

The professional experiences of the subject group in historically black colleges and universities and predominantly white colleges and universities were found to... 

Clinical trials may need to be conducted in certain study subject groups that are often either not included or are poorly represented in standard clinical development programmes. These include children, the elderly and those with a quantified degree of renal or hepatic impairment and ethnic minorities. Moreover, it may be necessary to consider specific studies in women of childbearing age for drugs other than those specifically designed for them, such as... 

There are several different kinds of laboratory safety data that require interpretation. These include routine screening for study subject selection, diagnostic evaluation of the subject, identification of risk factors, monitoring the progress of the disease or treatment, detection of adverse reactions, determination of appropriate dosages for certain at-risk subject groups (e.g. those with renal impairment). 

Figure 7 PVT reaction times prior to the first uncontrolled sleep attack during total sleep deprivation. Fourteen subjects completed 42 hr of total sleep deprivation and completed a 20-min PVT every 2 hr (represented by the closed circles) 19 subjects completed 88 hr of total sleep deprivation and completed a 10-min PVT every 2 hr (represented by the open circles). The number of test bouts (up to 30) prior to an uncontrolled sleep attack (failure to respond for 30 sec on the PVT) is represented on the bottom abscissa, with time prior to the sleep attack (up to 6 min) represented on the top abscissa. In both subject groups a progressive decline in performance on the visual PVT was evident within minutes of an uncontrolled sleep attack on console. This study also demonstrated an increase in subjective sleepiness (measured using the Stanford Sleepiness Scale) in the test bouts prior to the one in which the first sleep attack occurred. Taken together, these findings suggest that even a very sleepy subject cannot fall asleep while performing computerized tasks without some levels of awareness. (From Ref. 95.)...

Dr. I.M. Mujtaba is a Senior Lecturer in Chemical Engineering in the School of Engineering, Design Technology at the University of Bradford and is a member of the University Senate. He is a Fellow of the IChemE, a Chartered Chemical Engineer and is currently the Secretary of the IChemE s Computer Aided Process Engineering Subject Group. 

R. M. Rowell, G. R. Esenther, J. A. Youngquist, D. D. Nicholas, T. Nilsson, Y. Imamura, W. Kemer-Gang, L. Trong, andG. Deon, v Proceedings WFRO Wood Protection Subject Group, Honey Harbor, Ontario, Canada, Canadian Forestry Service, (1988), pp. 238-266. 

Table 3 - International Union of Forestry Research Organizations, Subject Group Air Pollution Maximal concentrations of air pollutants for the protection of forests (in pg/m air). ...

Although considerable progress has been made in the metabolic profile approach, a number of problems remain to be overcome. Many of these centre around the fluctuations in component composition, not from metabolic disorders, but brought about by other influences. These are principally due to diet and the metabolic variations in individuals in relation to activity. Drugs can also affect the excretion levels of compounds, in addition to the production of their own metabolites. These factors all make quantitative data difficult to obtain and evaluate. Careful statistical analysis of the results are necessary and a population of 500 subjects, grouped in age and sex, has been studied with a view to obtaining a suitable data base for urinary organic acids [370]. 

The year 1925 brought important changes and improvements in the subject index and the Richter type formula index. There were an increased concentration and a classification into main subject groups and subgroups. Key terms were printed in heavy black type an especially desirable feature was the addition in parentheses of all synonyms and alternate names of chemical compounds next to their main entry, in both the subject and formula indexes. 

There have been a number of Unilever-sponsored 3-year caries clinical trials during which calculus prevalence was also recorded. Table 1 summarises the variations in the scoring system employed. For the purpose of the present analysis, scores have been combined to produce two subject groups those with calculus and those without calculus. Mean baseline caries and calculus prevalence data from six trials are listed in table 2, whilst corresponding 3-year caries increment data and calculus prevalence at the end of each trial are listed in table 3. 

Slomiany and co-workers [102-105] have conducted a number of studies of salivary lipids from different subject groups, all involving low numbers of subjects. 

First, we describe the chemical composition of plaque fluid in relation to caries, then the role of plaque structure. Next, we discuss the influence of F retained in plaque, including site-to-site differences, followed by the effect of treatments that seek to deposit plaque calcium (Ca) and/or inorganic phosphate (Pi). A combination of small sample volumes and low constituent concentrations typically leads to high measurement variability that results, in turn, with authors often having difficulty in discriminating between subject groups. 

With regard to DS, DS = 1 implies a saturation condition in plaque fluid, DS < 1 undersaturation and DS > 1 supersaturation. In all subject groups the plaque fluid was saturated with respect to tooth enamel before sucrose exposure. Immediately after sucrose exposure, the plaque fluid was undersaturated for all subjects, whether they had caries or not. However, for those who were CA, the undersaturated state persisted for longer after sucrose exposure, because of retention of the acids produced. This would at least partially explain the high risk of demineralisation in CA subjects as shown in table 1. 

Subject group (n) Before sucrose 7 min after 15 min after 30 min after... 

Dawes, Dibdin and coworkers are contrasted. Of special interest, the authors present recent plaque data from subject groups in China, who have experienced different life histories to those from communities normally investigated. 

Sensitivity analysis is about asking how sensitive your model is to perturbations of assumptions in the underlying variables and structure. Models developed under any platform should be subject to some form of sensitivity analysis. Those constructed under a Bayesian framework may be subject to further sensitivity analysis associated with assumptions that may be made in the specihcation of the prior information. In general, therefore, a sensitivity analysis will involve some form of perturbation of the priors. There are generally scenarios where this may be important. First, the choice of a noninformative prior could lead to an improper posterior distribution that may be more informative than desired (see Gelman (18) for some discussion on this). Second, the use of informative priors for PK/PD analysis raises the issue of introduction of bias to the posterior parameter estimates for a specihed subject group that is, the prior information may not have been exchangeable with the current data. 

Hojo Y. 1981a. Subject groups high and low in urinary selenium levels Workers exposed to heavy metals and patients with cancer and epilepsy. Bull Environ Contam Toxicol 26 466-471. 

Phase 0. Recently introduced to speed up the development of promising treatments, or applications that requires small doses (esp. molecular imaging), this new phase of trial tests extremely small doses on a subject group. 

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