Valid Answer Research Articles

Postmenopausal Hormone Replacement Therapy and the Primary Prevention of Cardiovascular Disease

To evaluate the value of hormone replacement therapy (HRT) in the primary prevention of cardiovascular disease (CVD) and coronary artery disease (CAD). MEDLINE and Cochrane databases were searched for all primary prevention studies reporting CVD or CAD incidence, mortality, or both in association with HRT; reference lists, letters, editorials, and reviews were also reviewed. All studies were reviewed, abstracted, and rated for quality. Only studies of good or fair quality, according to U.S. Preventive Services Task Force (USPSTF) criteria, were included in the detailed review and meta-analysis. The summary relative risk with any HRT use was 0.75 (95% credible interval [CrI], 0.42 to 1.23) for CVD mortality and 0.74 (CrI, 0.36 to 1.45) for CAD mortality. The summary relative risk with any use was 1.28 (CrI, 0.86 to 2.00) for CVD incidence and 0.87 (CrI, 0.62 to 1.21) for CAD incidence. Further analysis of studies adjusting for socioeconomic status, as well as other major CAD risk factors, showed a summary relative risk of 1.07 (CrI, 0.79 to 1.48) for CAD incidence associated with any HRT use. Similar results were found when the analysis was stratified by studies adjusting for alcohol consumption, exercise, or both, in addition to other major risk factors, suggesting confounding by these factors. This meta-analysis differs from previous meta-analyses by evaluating potential explanatory variables of the relationship between HRT, CVD, and CAD. The adjusted meta-analysis is consistent with recent randomized trials that have shown no benefit in the secondary or primary prevention of CVD events. A valid answer to the role of HRT in the primary prevention of CVD will best come from randomized, controlled trials.

The university for the new market of knowledge

NETTUNO's Distance Teaching Model, based upon a network of traditional universities, is achieving significant results. Not only has NETTUNO contributed to the adoption of technologies by the Universities, but it also helped teachers to achieve new didactic skills. This allowed traditional universities to develop new ways of transferring knowledge using television and the Internet. On line course contents and the way they are delivered depend on university professors, therefore the quality control is assured and users are guaranteed as “consumers” of educational products. NETTUNO demonstrated that today distance University, thanks to the new telematic and satellite technologies, can provide a valid answer to the needs of the new market of knowledge: it can put its quality control trademark upon products; guarantee the user; help traditional university changing from an isolated system into a system capable of updating itself and integrating all the knowledge available on the Web and allow the knowledge interchange and interactivity world‐wide.

Wear Progression of Shoe Heels during Slip Resistance Measurements

Predicting changes in slip resistance performance with wear evolution is extremely difficult task and at present neither footwear nor flooring industries have a valid and reliable answer. Hence, in order to gain fundamental knowledge on wear mechanism, progressive wear and surface alteration processes of the shoes are investigated during repetitive dry rubbing. It is assumed that geometry changes of the shoe surface caused by wear development would be a major factor that affects the slip resistance performance. With the measurements of slip resistance, wear characteristics of two different shoes are comprehensively investigated based on the surface analyses and microscopic observations. For the systematic investigation of the surface alterations, topographic changes of each shoe were thoroughly examined on a regular time basis. The results show that surface alterations of each shoe were more severe than expected and occurred from the very early stage of sliding. It is also found that initially unstable friction process changed into the steady state friction process in the later stage of the slip resistance tests.

Debating complexity in modeling

Complexity in modeling would seem to be an issue of universal importance throughout the geosciences, perhaps throughout all science, if the debate last year among groundwater modelers is any indication. During the discussion the following questions and observations made up the heart of the debate.As scientists trying to understand the natural world, how should our effort be apportioned? We know that the natural world is characterized by complex and interrelated processes. Yet do we need to explicitly incorporate these intricacies to perform the tasks we are charged with? In this era of expanding computer power and development of sophisticated preprocessors and postprocessors, are bigger machines making better models? Put another way, do we understand the natural world better now with all these advancements in our simulation ability? Today the public's patience for long‐term projects producing indeterminate results is wearing thin. This increases pressure on the investigator to use the appropriate technology efficiently. On the other hand, bringing scientific results into the legal arena opens up a new dimension to the issue: to the layperson, a tool that includes more of the complexity known to exist in the real world is expected to provide the more scientifically valid answer.

Individual Autonomy and a Culture of Narcissism

Autonomy, self-determination, self-affirmation, emancipation: all these words refer to an ideal that orients the way in which our contemporary culture speaks about many moral and political problems. The importance of this ideal for us can be seen in the way we accept as obvious a number of ideas that follow from it. Most of us would certainly tend to accept that no universally valid answer can be given to the question of what kind of human life is truly meaningful or valuable and that, because of this, people should be granted as much freedom as possible to pursue a life that best corresponds with their own personal tastes and preferences. Many would go a step further and claim that people should also be encouraged to live as much as possible according to what they have themselves chosen, and that they should give up traditional forms of life and role patterns. One aspect of this cult of individual freedom or autonomy is the idea that we should develop a critical attitude towards anything established, accepted or traditional: every form of power or authority, prevailing moral norms and educational customs, traditional role patterns, etc. A further feature of this is the tendency to describe any improvement in the fortunes of the weak, the vulnerable and the less well off as an ‘emancipation’. The idea that the poor, the handicapped and the elderly should receive more support, assistance, respect and attention is translated by the assertion that they, too, should be ‘liberated’. The ideals that we associate with words like ‘emancipation’ or ‘self-affirmation’ were at one time innovative and revolutionary, but they gradually became established as accepted ways of thinking and thus became part of a new common sense. Nowadays, anyone wanting to be provocative will attain their goal more easily by scoffing at everything falling under the rubric of emancipation than by speaking out in its defence. This fact is characteristic of an ambiguity in our culture. While the ideals of self-affirmation and emancipation enjoy enormous popularity, in certain intellectual circles they are treated with suspicion. At stake here is the general image of humanity associated with these ideals. Thinkers such as Wittgenstein, Heidegger, Lacan, Derrida or Baudrillard have, each in their own way, attacked the idea of the autonomous subject and stressed that people’s most intimate thoughts and desires are determined by something that transcends them: by the language they speak or the culture to which they belong. Rejecting the idea of the autonomous subject is usually one aspect of a more general critique of ideas inherited from the Enlightenment. The question whether and to what extent this critique is justified occupies a central position in many contemporary philosophical discussions, and much of what goes on in contemporary philosophy can be described in terms of the opposition between those who would defend Enlightenment ideals (often indicated by the terms ‘humanism’ or ‘liberalism’) and those who would reject or cast doubt on those ideals. What I would like to discuss here undoubtedly fits into a framework that could be called ‘antiliberal’ or ‘anti-humanist’. However, it is certainly not my intention to criticize humanism or liberalism directly and systematically. In what follows, I will attempt to show that the unity or cohesion suggested by the term ‘autonomy’ does not in fact exist. It will turn out that this term is actually associated with three ideals which are not only distinct, but which are in relations of mutual opposition or tension. In addition, I would like to develop the idea that at

Entrepreneurship in a New Phase of Capitalist Development

There is widespread recognition today that entrepreneurial spirit and activity is vital for a market oriented, globally competitive economy. It is also recognised that local communities within countries and regions, can incur high costs of unemployment both as a result of adjustment to, and disconnectedness from, the global economic system. Attention to factors which will assist output growth and employment creation both at national and local community levels therefore becomes of prime importance. This paper explores the role of entrepreneurship in a new era of capitalist development. The need to increase the supply of entrepreneurship at the local community level is stressed. In this connection, a new concept of entrepreneurship, is developed, with an elaboration of “community entrepreneurship”. It is argued that community entrepreneurship which envisages the community supplying initiative and enterprise for the creation, transformation and expansion of employment creating ventures, is a valid answer to both an initial lack of individual entrepreneurial skills and employment opportunities in some labour market disadvantaged communities. Application of this concept is discussed within the New Zealand context.

Management of the young febrile child: a commentary on recent practice guidelines.

Recently published “practice guidelines”1,2 and randomized antibiotic trials3,4 reflect a climate of increased diagnostic testing, more frequent treatment, and more invasive (ie, parenteral rather than oral) treatment of febrile children 3 to 36 months of age. For children in this age group with a temperature ≥39.0°C, the guidelines1,2 suggest a white blood cell (WBC) count and provide two options with respect to obtaining a blood culture: all such children or those whose WBC count is ≥15 000/mm2. Culture of urine obtained by catheterization or suprapubic aspiration is recommended for all boys <6 months and all girls <24 months. The guidelines recommend empiric treatment with ceftriaxone, once again with two options: treat all such children or those whose WBC count is ≥15 000/mm2. These practice guidelines are based on a meta-analysis that pooled data from both randomized controlled trials and observational (nonexperimental) studies of clinical outcomes in young febrile children, and on the views of an expert panel chosen by the senior author.1,2 Although the guidelines have not been officially endorsed by any professional organization, they were developed by authors who are widely recognized in the field and thus could have an important impact on both clinical practice and health care policy. The clinical setting is that of a child with acute onset (≤4 days) of fever who does not appear “toxic” (ie, seriously ill) and has no apparent focus of bacterial infection (otitis media, pneumonia, osteomyelitis/septic arthritis, lymphadenitis, cellulitis, dysentery-like enteritis, or meningitis) after a history is obtained and a physical examination is performed. When confronted with such a child, the clinician must make a series of decisions: 1. Should she obtain diagnostic tests to identify an “occult” bacterial infection [such as pneumonia, bacteremia, meningitis, or urinary …

MMPI-2 clinical scales and 2-point code types: Impact of varying levels of omitted items.

The study investigated the impact of varying levels of item omissions (Cannot Say) on Minnesota Multiphasic Personality Inventory-2 (MMPI-2) 2-point code types. Valid MMPI-2 answer sheets were obtained from psychological outpatients (N = 100). Seven levels of item omission were investigated: 0 (baseline), 5, 10, 15, 20, 25, and 30. Omitted items were those most frequently skipped by psychiatric outpatients. Statistically reliable but very slight declines were seen on MMPI-2 clinical scales (M = -1.8 T-score points at 30 Cannot Says). Defined 2-point code types were relatively stable in the face of up to 30 omitted items. However, undefined code types were changed in 25% of the cases by 10 omitted items and in 39% of the cases by 30 omitted items. These results suggest that defined code types are relatively robust in the face of up to 30 omitted items, although undefined code types appeared much more likely to be changed by omitted items even at low levels. It is recommended that item content always be reviewed in the presence of omitted items to determine if specific clinical or content scales might be affected.

Population balance models and self-similar size distributions

To illustrate the fallaciousness of the linear population balance model (PBM) currently used in the mineral industry, a $10,000 challenge was made by Professor Thomas P. Meloy. In spite of numerous early promises, only one challenge response has been received to date. This response claims to generate self-similar size distributions. This paper: 1) shows that the challenger's response of a dynamic batch grinding solution is not a valid answer to this challenge, 2) examines and explores the implications of the proposed solution, and 3) offers the only actual dynamic batch PBM solution to the problem. The challenger's response to the Meloy Challenge has not accomplished the generation of a self-similar product size distribution using the dynamic batch PBM. The actual solution, not an approximation which was offered, is the dynamic PBM with different, time-varying breakage rate functions with unrealistic large values.

Chromaticity contrast, luminance contrast, and legibility of text

Abstract— The purpose of this investigation was to determine if color differences can improve legibility and compensate for insufficient luminance contrast. Several authors previously have answered this question positively on the basis of performance experiments. We argue that a valid answer cannot be given unless subjective data are used. In four experiments, subjective ratings were collected pertaining to multicolor CRT text displays. The displays were systematically varied with respect to both luminance contrast and chromaticity contrast. The results indicate that chromaticity contrast and luminance contrast are additive only under specific conditions. Chromaticity contrast cannot improve legibility if an acceptable level of luminance contrast is present. Generally, chromaticity contrast cannot be substituted for luminance contrast.

Statistical simulation of IC technology: A bipolar process example

Statistical simulation using design of experiments has been employed for integrated circuit technology development. A software program called STADIUM was developed to implement this statistical methodology. The software has been designed to be user friendly and to guide the engineer who is not a statistics expert through the process of deriving a valid statistical answer. Inputs to the STADIUM system include integrated circuit fabrication variations and when coupled with semiconductor process and device simulators can estimate the expected variations of device parameters such as transistor gain and threshold voltage. This paper presents the detailed procedure and results of a statistical simulation of a bipolar transistor technology.

Failure of irrigation projects and consequences for a different approach: a case study

Two examples of irrigation schemes are investigated for reasons of project failure. In one case (Gwelwongo, Burkina Faso), this was due mainly to socio-economic reasons: lack of interest of the local population for operation and maintenance of the scheme. In the other case (Wawotobi Irrigation Scheme, Southeast Sulawesi, Indonesia), the main reasons were ecological: no thorough site selection and/or preparation for irrigated fields in a swampy area. The projects do not generate any or, at least, insufficient revenue, and, therefore, the investment cannot be paid off. Secondary effects are less easily detected and monetarized, but still have detrimental effects for the local economy. In both cases, the incidence of malaria among the local population increased by unknown amounts, and in Burkina Faso, schistosomiasis has become a severe problem. This means high costs for medical treatment and a loss of manpower due to illness, which again reduces the productivity of local agriculture. The proposed solutions are technical ones and consist of improvement of drainage and reconstruction of decaying structures. This, however, is no guarantee for success. A different approach to such projects is necessary which takes into account not only (and not in the first place) the technical aspects of a possible development, but to a much greater extent the ecological and socioeconomic parameters. New questions must be asked at the start of a new development project. Ecological aspects should not only be included in an environmental impact assessment for an already defined project, but must play their role in the feasibility phase, as they can give valuable clues about the potential and limitations of the site. Involving the local population in the development of the project seem crucial. The funding agencies should accept the fact that their involvement does not end with the solemn inauguration of the scheme. Technical feasibility should not be the only criterion for selection of projects, and “no” should be accepted as a possible and valid answer.

Tunneling times: a critical review

The old question of "How long does it take to tunnel through a barrier?" has acquired new urgency with the advent of techniques for the fabrication of semiconductor structures in the nanometer range. For the restricted problem of tunneling in a scattering configuration, a coherent picture is now emerging. The dwell time ${\ensuremath{\tau}}_{D}$ has the status of an exact statement of the time spent in a region of space, averaged over all incoming particles. The phase times ${\ensuremath{\tau}}_{T}^{\ensuremath{\phi}}$ and ${\ensuremath{\tau}}_{R}^{\ensuremath{\phi}}$ are defined separately for transmitted and reflected particles. They are asymptotic statements on completed scattering events and include self-interference delays as well as the time spent in the barrier. Consequently, neither the dwell time nor the phase times can answer the question of how much time a transmitted (alternatively, reflected) particle spent in the barrier region. Our discussion of this question relies on a few simple criteria: (1) The average duration of a physical process must be real. (2) Since transmission and reflection are mutually exclusive events, the times ${\ensuremath{\tau}}_{T}$ and ${\ensuremath{\tau}}_{R}$ spent in the barrier region are, if they exist, conditional averages. Consequently, they must obey the identity ${\ensuremath{\tau}}_{D}=T{\ensuremath{\tau}}_{T}+R{\ensuremath{\tau}}_{R}$, where $T$ and $R$ are the transmission and reflection probabilities, respectively. The existence of this identity distinguishes tunneling in a scattering configuration from tunneling out of a metastable state. (3) Any proposed ${\ensuremath{\tau}}_{T}$ and ${\ensuremath{\tau}}_{R}$ must meet every requirement that can be constructed from ${\ensuremath{\tau}}_{D}$. On the basis of (2), the naively extrapolated phase times, as well as the B\"uttiker-Landauer time, must be rejected. The local Larmor times, as introduced by Baz', satisfy (2), but not every criterion of type (3). The local Larmor clock is therefore unreliable. The asymptotic Larmor clock shows the phase times, as it should. Finally, the inverse characteristic frequency of an oscillating barrier cannot always be defined. It is shown not to represent the duration of the tunneling process. This leaves the dwell time and the phase times as the only well-established times in this context. It also leaves open the question of the length of time a transmitted particle spends in the barrier region. It is not clear that a generally valid answer to this question exists.

The Determinants of Public Attitudes Toward the Welfare State

7This paper develops and tests a causal model of determinants of public attitudes toward welfare state programs. It proposes that support of welfare state programs is a function of self-interest and resultant identification with dominant social ideologies-zwrk ethic and social equality. Identification with these ideologies, in turn, affects endorsement of social rights and, hence, support of welfare state programs. Using data from 1983 Detroit Area Study, model is generally confirmed. The data also show, as expected, some important differences in effects of social ideologies on support of contributory vs. means-tested programs. The findings suggest that social groups supporting welfare state are economically and socially vulnerable who identify with social democratic values. It has become a truism that welfare state is in an era of crisis. In particular, welfare state is said to suffer from a legitimacy crisis as evidenced by recent decline in its growth rate and fiscal crisis of state (O'Connor 1973), rise to power of conservative political elites with an anti-welfare ideology, and declining credibility of intellectual underpinning of welfare state (Mishra 1984). Offe (1984, p. 157) asserts that both Left and Right agree that present welfare state is no longer the promising and permanently valid answer to problems of socio-political order of advanced capitalist economics. The intellectual attack on welfare state is not necessarily reflected in mass attitudes, and studies of public opinion toward welfare state portray a somewhat different picture. Trend data from polls over last half century indicate a fairly strong and consistent support of basic *Direct correspondence to Yeheskel Hasenfeld, School of Social Welfare, University of California, Los Angeles, CA 90024. ? 1989 The University of North Carolina Press

Chromosomal abnormalities in leukemia and lymphoma: clinical and biological significance.

Cytogenetic analysis of human tumors is one of the most rapidly progressing and exciting areas of cancer research. Major advances in our understanding of the specificity of some of the abnormalities observed have occurred within the last 10 years with the application of both chromosome banding techniques and improved methods of cell culture. Thus, the hypothesis put forward by Boveri at the turn of the century, that an abnormal chromosome pattern was intimately associated with the malignant phenotype of the tumor cell, can now be tested with the substantial hope of obtaining a valid answer (Boveri, 1914).

Organized Labor and the Housing Question: Public Housing, Suburbanization, and Urban Renewal

This paper examines those public-housing, suburbanization, and urban renewal policies in the United States of America that have evolved as a consequence of intraclass struggle. It is argued that the powerful constituency of organized labor was able, in the 1950s, to impose suburbanization as a valid answer to the housing question of the unions, while subsuming the housing demands, needs, and wants of less-powerful women and blacks. By the 1960s, the growing movements of women and blacks were able to challenge the dominance of the labor-liberal coalition and to successfully oppose the union-advocated policies of urban renewal and suburbanization.

Factors Affecting the Validity of Field Tests in Education

Field tests, although similar in some respects to experimental studies, are, in others, quite different. The field test and the classical experimental study seek to answer the same primary question: Is the treatment (program or product) effective? The goal of the evaluator and researcher alike is to provide a valid answer to that question, the concern of each is to control for the confounding effects of extraneous variables and to obtain results that are generalizable to a target population. There are, however, certain critical features inherent in the field test situation which are not present to as great a degree in the context of the experimental study. Much has been written about factors affecting the validity of experiments (see, e.g., Campbell & Stanley, 1963). In spite of the importance of field testing to educational evaluation, the literature provides evaluators with little information regarding the critical features of field tests and their

The design and analysis of experiments for the assessment of drug interactions.

It was pointed out that all fields of biological research have one feature common: inherent variability. Since this is the case and since it is not feasible to examine the entire population one is interested in, the experimenter is forced to give probability statements concerning any treatment differences observed. In order to do this, it is necessary for the experiment to be designed in such a way that a statistical analysis of the data will yield a valid answer to the question, "What is the probability that the differences observed could have occurred by chance?" The importance of randomization in the selection of the samples was emphasized. The problem of determining the sample size was discussed in relation to Type I (rejecting the null hypothesis when it is true) and Type II (accepting the null hypothesis when it is false) errors. It was suggested that too little attention is given to the possibility of Type II errors in biological research. It was emphasized that the specific question, or questions, one is asking should be precisely formulated prior to the design of the experiment, since hazily formulated ideas are difficult to discuss and virtually impossible to test for correctness. Once the experiment has been designed, both the questions and the design should be critically and logically evaluated for any fallacies. If the investigator has any doubts about the design or the manner in which the data will be analyzed, a statistician should be consulted before the experiment is conducted. A statistician cannot extract meaningful results from data collected with a faulty design. It was emphasized that it is important to know both the dose effect and time effect of each substance on the responses to be measured, in order to provide a rationale for the doses used in the interaction studies and the time after dosing at which the effect is to be measured. The design of drug interaction experiments is based, in part, on whether or not both substances when given alone affect the response. If both substances are active, one determines the potency of one substance relative to the other in affecting the response. This can be done for either quantitative or quantal data. Once the relative potency has been determined, subsequent studies involve combining fractional doses of the substances and comparing the results against those obtained using standard doses of the substances individually. Doses of the combination and the single substances are picked such that equivalent responses should be obtained if the effect of the two together is additive. The null hypothesis is that the two compounds behave as though they were different forms of the same substance, one of which is possibly (depending on the potency ratio) diluted with an inert substance. Equivalence of response can be tested using such parametric tests as Student's t or analysis of variance (or their nonparametric equivalents) for quantitative data. Additivity is inferred if the null hypothesis is accepted...

Solutions to Riddles

AMONG THE MANY GENRES OF FOLKLORE, the riddle is the most amenable to semiotic inquiry. In short dialogue sequences, riddling includes verbal metaphors, interpretations, and their rejections or validations. The immediate succession of a message, a decoding, and a feedback condenses a process that extends over a longer span of time in the communication process of many other genres. Moreover, inherent in the riddle is a deliberate ambiguity which is designed to reveal and conceal its subject at one and the same time. Success in untangling the true meaning of the riddle-sentence from the knots of verbal deceit depends upon the confirmation of the solution by the riddle poser. However, his acceptance of the answers is often whimsical and manipulative; he can reject certain solutions on one occasion and acknowledge them the next time, as long as he is able to maintain his socially advantageous position.' Such social manipulations of truth demonstrate an important attribute of the riddle, its capacity for multiple solutions.2 There is no single valid answer to the riddle; neither is there a single, objective, true solution to its puzzle. Each question has a range of alternate possible solutions, each of which could adequately correspond to a metaphoric description, and all of them combined would be a set of referents. Such a view implies that, from a broad cultural perspective, there are no wrong answers to riddles. Each solution can be valid as long as it is offered by a native speaker of the language who shares the cultural experience of the community and has an adequate familiarity with traditional knowledge. Yet this broad interpretation of truth in riddles should not ignore the fact that, in actual performance, there are linguistic and cultural

Human capital theory, the diversity of societies and the problem of quality in education

Taking off from the “human capital theory” vs. “screening theory” debate, the paper seeks to distinguish at least ten different causal strands which potentially enter the explanation of the commonly observed correlation between earnings and educational qualification. Debates on this issue are commonly vitiated by two factors: (i) the failure to distinguish between mechanisms which operate in fluid market situations and those which operate in bureaucratized economies with administered careers, (ii) the assumption that there can be a universally valid answer to the question “Why do earnings and certificates correlate?” Various institutional and historical factors cause considerable differences in the relative importance of the ten linking mechanisms in different countries. Of the greatest importance is one general difference between early and late developers. Schools in developing countries are generally less effective in fostering the sort of mental attitudes and abilities which conduce to economic development chiefly because, for a variety of reasons, schooling is more examination-oriented than in richer countries. These crucial aspects of the quality of education are too often overlooked, presumably for reasons which have to do with the nature of the economics and educational professions.