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Scientific experiment

The reviewer should estabHsh that the laboratory reporting the study has the necessary professional reputation, scientific experience, and expertise in the area investigated. It should be confirmed that adequate quaHty-control faciHties are in place and good laboratory practices and procedures foUowed. [Pg.237]

For the reasons described, no specific test will be advanced here as being superior, but Huber s model and the classical one for z = 2 and z = 3 are incorporated into program HUBER the authors are of the opinion that the best recourse is to openly declare all values and do the analysis twice, once with the presumed outliers included, and once excluded from the statistical analysis in the latter case the excluded points should nonetheless be included in tables (in parentheses) and in graphs (different symbol). Outliers should not be labeled as such solely on the basis of a fixed (statistical) rule the decision should primarily reflect scientific experience. The justification must be explicitly stated in any report cf. Sections 4.18 and 4.19. If the circumstances demand that a mle be set down, it is best to use a robust model such as Huber s its sensitivity for the problem at hand, and the typical rate for false positives, should be investigated by, for example, a Monte... [Pg.59]

Gas density has a significant effect on the interactions among molecules of a gas. As molecules move about, they collide regularly with one another and with the walls of their container. Figure 5-13 shows that the frequency of collisions depends on the density of the gas. At low density, a molecule may move all the way across a container before it encounters another molecule. At high density, a molecule travels only a short distance before it collides with another molecule. As our Tools for Discovery Box describes, many scientific experiments require gas densities low enough to provide collision-free environments. [Pg.306]

Because the major cost of a commercial MRI is the magnet, there have been attempts to develop portable MRI consoles, that is, the requisite instrumentation for MRI minus the magnet, that could be transported to a medical MRI facility so that a scientific experiment could be set up independently of the medical MRI console (see Chapter 2.2). There are also efforts to develop compact NMR/MRI instruments for non-traditional uses. Granular studies would easily fit into this category. [Pg.506]

Shirley, John William. The scientific experiments of Sir Walter Raleigh, the Wizard Earl, and the Three Magi in the Tower, 1603-1617. Ambix 4 (1949-1951) 52-66. [Pg.246]

Pepper, John Henry. The boy s playbook of science including the various manipulations and arrangements of chemical and philosophical apparatus required for successful performance of scientific experiments, in illustration of the elementary branches of chemistry and natural philosophy. London, New York Routledge, 1866. [Pg.565]

As in other fields of nanosdence, the application of STM techniques to the study of ultrathin oxide layers has opened up a new era of oxide materials research. New emergent phenomena of structure, stoichiometry, and associated physical and chemical properties have been observed and new oxide phases, hitherto unknown in the form of bulk material, have been deteded in nanolayer form and have been elucidated with the help of the STM. Some of these oxide nanolayers are and will be of paramount interest to the field of advanced catalysis, as active and passive layers in catalytic model studies, on the one hand, and perhaps even as components in real nanocatalytic applications, on the other hand. We have illustrated with the help of prototypical examples the growth and the structural variety of oxide nanolayers on metal surfaces as seen from the perspective of the STM. The selection of the particular oxide systems presented here refleds in part their relevance in catalysis and is also related to our own scientific experience. [Pg.182]

This was the original method used to produce electricity (i.e., an electrical current) for scientific experiments. Thus, if copper and zinc electrodes are... [Pg.192]

The most studied component of blood pressure disturbances in the elderly is by far, high blood pressure. Only a very few scientific experiments have been performed on low blood pressure in the elderly. This is, among other reasons, due to the... [Pg.70]

Apart from the use of practical explosive tests to assess damage patterns at a crime scene, it has been suggested that patterns of deposition of explosives residue could be similarly assessed [27]. Practical experience shows that even in a planned scientific experiment there are huge variations in residue deposition patterns because of the difficulty of controlling aU the relevant parameters. Events at a crime scene are completely uncontrolled and subject to even greater variations, and to make matters worse the design, placement and performance of the explosive device are at best inferred rather than known. The presence of chemical traces of a particular explosive at a bomb scene is a useful indication of the material used the drawing of any conclusions beyond that point should be subject to extremely cautious consideration. [Pg.238]

An abstract comes at the very beginning of your paper. It is usually required for scientific or mathematical papers that have involved the accumulation of data or facts based upon scientific experiments or formulas. Sometimes, however, it is required for papers written on historical or other subjects. An abstract is simply a short, succinct summary of your paper. It is no more than a paragraph in length and should be written after you have completed your entire paper even though it comes at the beginning of your work. In essence, you can think of an abstract as the blurb or commentary that you see on the back of a book cover. While these blurbs are usually written on the back of books so that readers will buy them. [Pg.116]

Numberless phytotherapeutic preparations for the treatment of BPH are on the market. However, the active ingredients and the mode of action remain unknown for most of them. Serenoa repens (also known as saw palmetto from the American dwarf palm) has been investigated in a number of scientific experiments and in chnical trials. It has been proposed that it inhibits the 5aR-2. Since Serenoa repens has no effect on serum prostate-specific antigen (PSA) levels, the mode of action might certainly differ from the mode of action of finasteride or dutasteride [129]. [Pg.48]

Priestley wasn t wealthy like Boyle and Cavendish so he didn t have the leisure to spend as much time on scientific experiments as they did. However, by this time his fame had grown and he soon had a patron. William Petty, the second earl of Shelburne, admired Priestley s scientific work and offered him a post supervising the education of his two sons and collecting material on subjects under discussion in parliament. The salary was to be two and a half times what he was then earning, and Shelburne also provided his new... [Pg.105]

Some of the books on the design of scientific experiments appear far too theoretical for use in college field trials. However, three books in particular have proved useful in this Institute ... [Pg.1]

This work shows the exceptional physics that can be done with a STM operated at cryogenic temperatures and the availability of STMs working down to liquid helium temperature opens broad avenues of research in the coming years. No doubt that among the many future scientific experiments accessible with low temperature STMs, the real-space electronic characterization of the metal-superconductor transition in /c-phases of BEDT-TTF salts, because Tc > 4 K, as well as the study of magnetic ordering in MOMs, will certainly occupy a relevant position. [Pg.272]

Decree n° 2001-486 relating to the protection of animals used in scientific experiments described in the Journal Officiel de la Republique Fran9aise on 6 June 2001... [Pg.109]

Many people worry that tests for anxiety using animals are harmful or cruel to the animals tested. Scientists also worry about this. No one enjoys inflicting discomfort or pain on a living creature. On the other hand, it is difficuit to measure something aversive without somehow creating an aversive environment. Scientists try to come up with models that will reproduce the effect they want (in this case, anxiety) with the least amount of disturbance to the animal. In fact, in order to use animals for any scientific experiment, it is necessary to formally apply for permission to a panel of veterinarians and other animal care specialists. This panel reviews the proposed experiment and considers whether it is acceptable. Many times, the panel will insist that an experiment be changed if it causes too much pain or trauma to the animai. In this way, scientists and animai health experts hope to limit the amount discomfort to which any iaboratory animal is subjected. [Pg.66]

A charitable interpretation of fhe concerns raised by Gilleffe, Krier, Hornstein, and others is that, under special circumstances, initial distribution determines the pattern of fhe resulfing frades. I fhink their concerns are invalid, but both Goase-supporting and Goase-refuting scenarios are conjecture rather than scientific experiments. [Pg.51]

The capacity of a chemical to cause harm is what the hazard identification stage of risk assessment is intended to identify - the hazards of a chemical are the adverse effects [harm] which [it] has an inherent capacity to cause (Article 2 of Directive 93/67/EEC). The identification of adverse effects on the health of humans and wildlife relies heavily on tests on laboratory animals. I have already discussed some of the many uncertainties that result from the use of animal tests. A key question is whether there are viable alternatives. Before proposing an alternative testing strategy I first consider animal tests as scientific experiments and ask whether they are good experiments, given what we want to find out. [Pg.104]

This criticism suggests that the test should create a situation that is as near as possible to the real situation - that it should aim to represent the world outside the laboratory, be carried out on the species that are of concern, and so on. However, this is obviously not possible because of ethical and practical difficulties, not the least of which would be the very large number of tests required. Moreover, this response fails to understand how science actually works. Good scientific experiments do not attempt to replicate the complex, messy world outside the laboratory rather they are designed to provide the conditions in which particular capacities that things have to behave in certain ways are revealed. Such ideal conditions are ones in which the capacities we are interested in give rise to the behaviour that characterizes them without interference from other causes (Cartwright, 1999, p84). [Pg.105]

Because of the importance of this furiously progressing work and the urgency of the escalating electrical energy crisis worldwide, a paper [22] describing our results was placed on a Department of Energy Website, (see Ref. 22). The paper was later moved to a restricted DOE site reserved for scientists, until such time as independent testing verification and independent replication is obtained, to assure a fully valid scientific experiment. [Pg.710]

Because of the great potential for unseen error in any procedure, the results of a scientific experiment are considered valid only if they can be reproduced by other scientists working in similarly equipped laboratories. This restriction helps to confirm the experimental results and lends more credence to an interpretation. [Pg.8]

Today, the results of many scientific experiments confirm the atomic nature of matter. Contrary to Daltons notion of the indivisible atom, however, an accumulation of evidence tells us that atoms are in fact divisible and that they are made of smaller particles called electrons, protons, and neutrons. For the remainder of this chapter, we explore these subatomic particles in detail, continuing with our historical perspective. [Pg.87]

The evidence of scientific experience, thus far, is solidly behind the psychological theories that assume an internal origin of the "knowledge" or stimuli of unusual experiences. However, we cannot exclude the possibility that the classical mystic experience, LSD reactions, certain phases of acute psychosis, and other unusual experiences represent conditions of special receptivity to external stimuli ordinarily excluded or ignored in the normal state. [Pg.320]

This book is based on our scientific experience, and largely capitalizes on our previous books, of which we here maintain (and try to improve) the pictorial way of presenting theoretical aspects ... [Pg.381]

A major scientific experiment devoted to the search for antimatter originating from outside of our galaxy is presently being conducted by NASA. The experiment is a part of the project aiming at studies of matter, antimatter and dark matter in space. This project, coordinated by the Department of Energy (DOE), is a large collaboration of more than 30 universities, and will be conducted with the help of a state-of-the-art... [Pg.190]


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