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Ecological and life-history data on the Northern European macromoth (Lepidoptera: Macroheterocera) fauna is widely available and ideal for use in answering phylogeny-based research questions: for example, in comparative biology. However, phylogenetic information for such studies lags behind. Here, as a synthesis of all currently available phylogenetic information on the group, we produce a supertree of 114 Northern European macromoth genera (in four superfamilies, with Geometroidea considered separately), providing the most complete phylogenetic picture of this fauna available to date. In doing so, we assess those parts of the phylogeny that are well resolved and those that are uncertain. Furthermore, we identify those genera for which phylogenetic information is currently too poor to include in such a supertree, or entirely absent, as targets for future work. As an aid to studies involving these genera, we provide information on their likely positions within the macromoth tree. With phylogenies playing an ever more important role in the field, this supertree should be useful in informing future ecological and evolutionary studies.

1. Comparative studies on insect life histories are facilitated by the increasing availability of reliable phylogenies but are hampered by the scarcity of comparable data. Fortunately, morphological proxies of some life‐history traits can be measured on preserved specimens. 2. This study compared values of size‐related life‐history traits among a tropical (Ugandan) and a temperate (Estonian) assemblage of geometrid moths. 3. A comparative analysis based on an originally derived phylogeny revealed that tropical moths were, on average, larger than temperate ones. Tropical moths also had somewhat lower relative abdomen masses than temperate ones. This indicates that the tropical rather than the temperate moths tend to use an income (rather than capital) breeding strategy. Nevertheless, no difference was found in a related index of pro‐ovigeny. When body size was accounted for, tropical moths were found to lay smaller eggs than temperate ones. 4. The differences between the two compared areas are consistent with selection on higher mobility of the moths imposed by the more diverse tropical vegetation. Relatively larger eggs of temperate moths may constitute an adaptation to overcome the presumably stronger quantitative defences of their host plants. 5. Overall, however, we conclude that the differences in ecologically relevant size‐related traits are relatively low among moth assemblages of a tropical and a temperate forest region, indicating that these environments may not impose radically different selective pressures on insect life histories.

Research on evolutionary forces determining optimal body sizes has primarily relied on experimental evaluation of respective selective pressures. Accounting for among-species variation through application of phylogenetic comparative methods is a complementary although little used approach. It enables the direct association of body size values with particular environments. Using phylogenetically explicit comparative analyses, we show that small body size is associated with diurnal (rather than nocturnal) activity of adults among temperate species of the moth family Geometridae. The association of an exclusively adult trait with species-specific body size suggests that optimal body sizes are at least partly determined by the costs being a large adult, as opposed to the more frequently considered costs of attaining large size. It appears likely that size-selective predation by insectivorous birds is the primary factor responsible for selection against large body size in day-flying moths.

Understanding how and why some groups have become more species-rich than others, and how past biogeography may have shaped their current distribution, are questions that evolutionary biologists have long attempted to answer. We investigated diversification patterns and historical biogeography of a hyperdiverse lineage of Lepidoptera, the geometrid moths, by studying its most species-rich tribe Boarmiini, which comprises ca. 200 genera and ca. known 3000 species. We inferred the evolutionary relationships of Boarmiini based on a dataset of 346 taxa, with up to eight genetic markers under a maximum likelihood approach. The monophyly of Boarmiiniis strongly supported. However, the phylogenetic position of many taxa does not agree with current taxonomy, although the monophyly of most major genera within the tribe is supported after minor adjustments. Three genera are synonymized, one new combination is proposed, and four species are placed in incertae sedis within Boarmiini. Our results support the idea of a rapid initial diversification of Boarmiini, which also implies that no major taxonomic subdivisions of the group can currently be proposed. A time-calibrated tree and biogeographical analyses suggest that boarmiines appeared in Laurasia ca. 52 Mya, followed by dispersal events throughout the Australasian, African and Neotropical regions. Most of the transcontinental dispersal events occurred in the Eocene, a period of intense geological activity and rapid climate change. Diversification analyses showed a relatively constant diversification rate for all Boarmiini, except in one clade containing the species-rich genus Cleora. The present work represents a substantial contribution towards understanding the evolutionary origin of Boarmiini moths. Our results, inevitably biased by taxon sampling, highlight the difficulties with working on species-rich groups that have not received much attention outside of Europe. Specifically, poor knowledge of the natural history of geometrids (particularly in tropical clades) limits our ability to identify key innovations underlying the diversification of boarmiines.

Specificity is one of the fundamental concepts in ecology. Host specificity of phytophagous insects has been of particular interest because of its crucial role in diversification and life-history evolution. However, the majority of tropical insects remain insufficiently explored with respect to their host-plant relations. A lack of respective data is also hindering the debate over whether higher levels of host-plant specificity prevail in tropical insects compared to temperate ones. We investigated host-plant specificity of forest geometrid moths (Lepidoptera: Geometridae) in equatorial Africa using host-plant acceptability trials with neonate larvae, with the addition of field observations. We compare our experimental data to the (well-known) host-specificity patterns of closely related temperate (hemiboreal) species. Similarly to the temperate region, there were broadly polyphagous tropical species in several clades of Geometridae utilizing hosts belonging to different plant families. Phylogenetic comparative analysis returned no significant differences in host specificity between the two regions. Our study contributes to the evidence that host-plant specificity of herbivores is not necessarily substantially higher in tropical than temperate regions.

Predictive classifications of life histories are essential for evolutionary ecology. While attempts to apply a single approach to all organisms may be overambitious, recent advances suggest that more narrow ordination schemes can be useful. However, these schemes mostly lack easily observable proxies of the position of a species on respective axes. It has been proposed that, in insects, the degree of capital (vs. income) breeding, reflecting the importance of adult feeding for reproduction, correlates with various ecological traits at the level of among-species comparison. We sought to prove these ideas via rigorous phylogenetic comparative analyses. We used experimentally derived life-history data for 57 species of European Geometridae (Lepidoptera), and an original phylogenetic reconstruction. The degree of capital breeding was estimated based on morphological proxies, including relative abdomen size of females. Applying Brownian-motion-based comparative analyses (with an original update to include error estimates), we demonstrated the associations between the degree of capital breeding and larval diet breadth, sexual size dimorphism, and reproductive season. Ornstein-Uhlenbeck model based phylogenetic analysis suggested a causal relationship between the degree of capital breeding and diet breadth. Our study indicates that the gradation from capital to income breeding is an informative axis to ordinate life-history strategies in flying insects which are affected by the fecundity vs. mobility trade off, with the availability of easy to record proxies contributing to its predictive power in practical contexts.

Diet breadth and the degree of capital breeding have been established as major determinants of species-specific ecology of herbivorous insects. Both of these variables are related to resource foraging and therefore can be expected to have effects on sensory capacity. However, such effects have remained poorly studied, let alone in phylogenetically explicit multi-species comparisons. We contribute to filling this gap in a study of 60 species of geometrid moths (Lepidoptera: Geometridae), using adult head measures (eye size, antennal length and shape, forehead width) as indices of sensory capacity. When controlled for body size, eyes of the more capital breeding species (i.e. those with low contribution of adult feeding to reproduction) were found to be smaller, and female antennae shorter, than in income breeders. Feathery (vs simple filiform) male antennae were more frequently present in the capital breeders and in larger species. Regarding diet breadth, generalist species were found to have relatively wider male foreheads than specialists. The results suggest that (a) breeding strategy rather than diet breadth predicts sensory capacity in geometrids, (b) capital breeding (vs income breeding) is related to low sensory capacity in females, and (c) in contrast, males of the capital breeding species have evolved towards elevated olfactory capacity.

Numerous studies have suggested a general relationship between the degree of host specialization and body size in herbivorous animals. In insects, smaller species are usually shown to be more specialized than larger-bodied ones. Various hypotheses have attempted to explain this pattern but rigorous proof of the body size-diet breadth relationship has been lacking, primarily because the scarceness of reliable phylogenetic information has precluded formal comparative analyses. Explicitly using phylogenetic information for a group of herbivores (geometrid moths) and their host plant range, we perform a comparative analysis to study the body size-diet breadth relationship. Considering several alternative measures of body size and diet breadth, our results convincingly demonstrate without previous methodological issues-a first for any taxon-a positive association between these traits, which has implications for evaluating various central aspects of the evolutionary ecology of herbivorous insects. We additionally demonstrate how the methods used in this study can be applied in assessing hypotheses to explain the body size-diet breadth relationship. By analyzing the relationship in tree-feeders alone and finding that the positive relationship remains, the result suggests that the body size-diet breadth relationship is not solely driven by the type of host plant that species feed on.

A count of the type and brand of spent alkaline batteries from a collection program operated by Butler County, Ohio was performed to determine the level of brand diversity, to provide estimates of the size of the waste stream, and quantities collected for recycling and for landfilling. The program has a total of 37 school drop off sites at both public and private elementary, middle and high schools. Several additional sites for battery drop include public libraries in the towns of Hamilton, Fairfield, Oxford, two county government administration centers, and two major retail stores in Fairfield and West Chester townships. A total of 32,866 spent alkaline batteries with a calculated mass of approximately 943.37 kg representing 10–15% of the recycling collection were counted by size and brand type. All five types (AAA, AA, C, D, and 9V) of spent alkaline batteries had approximately 68–76% of the samples concentrated among three or four brands. The number of brands varied among types with AAA (123); AA (228); C (44); D (65); 9V (79). The total annual spent alkaline waste stream mass for Butler County is estimated to be 84,665 kg, and a mass of the spent alkaline battery waste stream collected for Butler County is approximately 7.4% (6289.1 kg) to 11.1% (9433.7 kg). Several other battery types (lead, Ni–Cd, lithium, and button batteries) were observed and comprised 60.2 kg. Butler County spends $10,000 to collect the batteries each year and the estimated cost for collecting all batteries in the County would be an additional minimum cost of $144,000 to $186,000 per year translating into a per capita cost of approximately $0.39–0.51 per Butler County resident annually. The results of this investigation are useful for recycling program development, developing environmental policies specific to the United States and can be used for comparative purposes with other battery waste streams globally.

We present a phylogenetic comparative study assessing the evolutionary determinants of egg size in the moth family Geometridae. These moths were found to show a strong negative allometric relationship between egg size and maternal body size. Using recently developed comparative methods based on an Ornstein-Uhlenbeck process, we show that maternal body size explains over half the variation in egg size. However, other determinants are less clear: ecological factors, previously hypothesized to affect egg size, were not found to have a considerable influence in the Geometridae. The limited role of such third factors suggests a direct causal link between egg size and body size rather than an indirect correlation mediated by some ecological factors. Notably, no large geometrid species lay small eggs. This pattern suggests that maternal body size poses a physical constraint on egg size, but within these limits, there appears to be a rather invariable selection for larger eggs.

Sociality in insects may negatively impact on species richness. We tested whether termites have experienced shifts in diversification rates through time. Supertree methods were used to synthesize family-level relationships within termites, cockroaches and mantids. A deep positive shift in diversification rate is found within termites, but not in the cockroaches from which they evolved. The shift is responsible for most of their extant species richness suggesting that eusociality is not necessarily detrimental to species richness, and may sometimes have a positive effect. Mechanistic studies of speciation and extinction in eusocial insects are advocated.

Several challenges exist in ichnotaxonomy: overcoming the perceived distinction between invertebrate and vertebrate ichnotaxonomy, standardizing terminology, rationalizing the plethora of ichnotaxa already in existence, and developing principles for diagnosing new ichnotaxa. Ichnotaxa should be based on morphology, and this morphology incorporates three key components; the behaviour expressed, the producer, and the substrate. Invertebrate and vertebrate ichnotaxa can both be accommodated within this framework, but they differ in the relative contributions of these components. The key to justifying the synonymy of existing ichnotaxa is the recognition of intergrading specimens. However, this is only the case for minor morphological variants (i.e. those representing minor differences in behaviour, such as gait parameters or stance; or minor differences in preservation, such as undertrack fallout or slight differences in substrate conditions). Intergrading specimens should not be used to justify synonymy between major morphological variants (i.e. those representing major behavioural differences, defined herein as ethological categories; or major differences in preservation, such as formation in soup, soft and firmgrounds), and such specimens should be denoted as hybrids (e.g. Cruziana×Rusophycus). New ichnotaxa should ideally be based on observations of large samples of material, so that recurrence is demonstrable, and morphological continuums, or subset relationships, representing minor morphological variation, are identified. Ichnotaxa may only be erected on the basis of limited material if they truly represent a unique morphology. These principles have been developed with arthropod trackways in mind, but it is hoped that they will be of more general utility.

A comprehensive systematic neoichnological study was conducted to investigate the affect of substrate conditions on the morphology and survivorship of terrestrial arthropod trackways. Experiments utilized five different extant arthropods, representing a range of body forms and higher taxa: discoid cockroaches (Blaberus discoidalis), emperor scorpions (Pandinus imperator), Chilean rose tarantulas (Grammostola rosea), African giant black millipedes (Archispirostreptus gigas), and common woodlice (Oniscus asellus). Trackways were produced on substrates of various grain size and moisture content, in protocols simulating subaerial and transitional subaqueous–subaerial depositional settings. The results are illustrated systematically to provide a comprehensive record of the morphological variation that can occur in arthropod trackways under different substrate conditions. General morphological trends, of increased definition of individual tracks and loss of tracks within series, are highlighted as “dry to dampground” and “soft to firmground” surface moisture taphoseries in the subaerial and transitional subaqueous–subaerial protocols respectively. Heavier arthropods produced trackways across a broader moisture and grain size range, whilst different arthropods can produce similar trackways under certain conditions. Undertrack fallout was investigated using discoid cockroaches, and the resultant undertrack taphoseries mimics the surface moisture taphoseries. Previous hypotheses on the factors that influence trackway survivorship were also investigated. Increasing concentrations of clay minerals exponentially increases the survivorship of trackways subjected to an air current, whereas increasing surface moisture has a linear affect, and a combination of the two provides excellent conditions for trackway survivorship. The results of this study are fundamental to the study of fossil arthropod trackways and can be used to aid ichnotaxonomic revisions, whilst also facilitating the identification of trace fossil producers and highlighting potential biases in palaeoecological reconstructions based on trace fossils.

That emotions can both facilitate learning and block learning is an accepted psychological fact. The author considers those factors which he feels develop an optimal learning situation in the classroon.

The problem of adults with severe mental illness parenting minor children is a growing concern. These clients suffer from concerns that negatively affect them and their children. This study showed many clients seeking services at public mental health agencies are parents of minor children and have had a history of family dysfunction. Prevalence rates, demographic characteristics, types of mental illness diagnoses, family background variables, and some current issues regarding these clients were examined. The study concludes with clinical implications for clients and their families and calls for a family focused approach.

PURPOSE To review current research and recommendations on weight loss and weight control and provide suggestions for health care providers who furnish weight management counseling. DATA SOURCES Scientific publications, clinical guidelines, and government sources CONCLUSIONS Research reaffirms the long-held understanding that weight loss can be accomplished only through a reduction in the number of calories consumed and an increase in exercise. Weight maintenance requires life-long behavioral change combining moderate exercise, lower fat intake, increased fruit and vegetable consumption, as well as social support. Fad diets and medications are not the answer to long-term weight maintenance. IMPLICATIONS FOR PRACTICE The essential components of a weight loss or weight management program include: calorie reduction of 300–500 calories per day, appropriate exercise, variety in food choices, increased consumption of grains, fruits, and vegetables, and reduction of fat to no more than 30% of daily calories. Clients should be referred to dietitian and exercise consultants as needed.

A synthetic control chart designed to detect shifts in the process mean can be represented as a runs rule chart with a head start feature. A Markov chain model of the synthetic control chart is proposed for the evaluation of the zero-state and steady-st..

The average run length performances of Shewhart charts with supplementary runs rules and zone control charts are studied when the process mean changes linearly over time. Shewhart charts with all possible combinations of the typical runs rules are compared to zone control charts with identical false alarm rates. The zone control charts generally outperform the Shewhart charts in detecting a process mean that is changing linearly over time.

The volume ratio between piezoelectric and magnetostrictive phases is an important parameter for magneto-electric (ME) composites. The ME voltage coefficients can be enhanced greatly at optimum volume ratio. However, no previous report has focused on the study of the volume ratio effect on ferromagnetic-ferroelectric-substrate multilayer composites. We consider an arbitrary laminated structure of length 2L and N layers. In this case, there is no middle plane of the bar that can serve as a plane of symmetry. For simplicity we assume that the multilayer structure is two dimensional (i.e. bar structure), and the field functions depending only on the space coordinates X1, X2. In the Cartesian system of coordinates the X1 axis is directed along the bar length, the X2 -across the width, and X3 is orthogonal to X1 and X2. It is assumed that piezoelectric layers are poled in the X1 direction (L-L mode). It should be mentioned that the proposed theory can be successfully applied to multilayer structures when the polarization direction of the piezoelectric layers is along the X2 direction, or when some of them are along the X1, and others along X2, or X3 directions. An averaging method is used for deriving effective material parameters of composites. We consider only (symmetric) extensional deformation in this model and at first ignore any (asymmetric) flexural deformations of the layers that would lead to a position dependent elastic constants and the need for other methods to be applied. Using the continuity conditions for magnetic and electric fields, as well as the open and closed circuit conditions, one obtains the analytic expression for longitudinal ME voltage coefficient, which depends on electro-mechanical material properties and thicknesses of the layers. Analytical expression for ME coefficient allows us to find the optimal volume ratio of layers, for which the ME coefficient approaches to its maximum value.

The purpose of this study was to investigate the effect of nonrandom allocation of organisms to treatments in aquatic toxicity tests on lethal concentration estimates. Random allocation of organisms is prescribed to avoid the introduction of systematic bias in these tests; however, completely random assignment is usually impractical. A source of systematic bias in a nonrandom allocation scheme is the potential inverse relationship between organism hardiness and the order in which organisms are captured for assigning to treatment (i.e., less hardy and hence more sensitive individuals are captured first). A Monte Carlo simulation experiment was performed to examine such an inverse relationship for a variety of random allocation schemes, focusing on the mortality endpoint in the fathead minnow larval survival and growth toxicity test. Results of the computer simulation experiment indicated that nonrandom allocation of organisms can produce significant bias in estimates of lethal concentration values. Any attempt at randomization resulted in approximately unbiased estimates of lethal concentration values; however, variance of the estimates increased as allocation schemes deviated from the completely random allocation. This study illustrates the importance of proper training of laboratory personnel to implement some form of random organism allocation. Furthermore, many partial random allocation schemes (i.e., those allocating more than one organism at a time) may still yield unbiased estimates of potency endpoints.

Classroom practice should be directly related to a theory of learning. Mathematics educators have used the works of theorists such as Skinner, Piaget, and Bruner to guide their work. Recant innovations in classroom practice include listening to students' explanations of their mathematical reasoning processes, recognizing students' potential for mathematical reasoning. recognizing the number and complexity of processes necessary for the solution of problems, and providing experiences that encourage students to construct assimilation paradigms to help them reconcile new concepts with their current knowledge base and thus construct new knowledge. Do we have a sound base of theoretical support for these new practices? The author argues that the requisite theories do exist, but probably not as a single unified theory at the present time.

This paper presents a model and a method for the high-level datapath synthesis of pipelined ASIC architectures, starting with a behavioural description of the system consisting of theoretical operational units with arbitrary operation duration. The method calculates the minimal number of buffers to be inserted, optimally selects the number of types of additional operational units, and determines the minimal number of required copies. The aim of the procedure is to ensure a latency which can be given in advance, and could not be achieved without additional buffers and extra copies of the operational units. The method provides a solution to the resource allocation problem by establishing a compatibility relation between the concurrent operations. The constraints for the types of processors to be applied can vary, depending upon the hardware resources.

With this Special Issue, entitled “Visions of School Mathematics,” the Journal of Mathematical Behuvior begins the most exciting project that it has undertaken, an international discussion of what mathematics students should be learning. This includes both the selection of “content” or “topics,” and also the more subtle, but even more important question of whut kind of knowledge students need to develop about each topic. This distinction may require explanation. Deciding whether the curriculum should include the topic of “adding fractions” falls into the first category, as a “content” decision. But in what way do we want students to be able to deal with “adding fractions”‘? Know from memory a rote rule’? Be able to show how this rule can be arrived at by thinking of certain heuristics? Be able to make numerical replacements for the variables in a formula such as

A general model for the zone control chart is presented. Using this model, it is shown that there are score vectors for zone control charts which result in superior average run length performance in comparison to Shewhart charts with common runs rules. A fast initial response (FIR) feature for the zone control chart is also proposed. Average run lengths of the zone control chart with this feature are calculated. It is shown that the FIR feature improves zone control chart performance by providing significantly earlier signals when the process is out of control.

We present a phylogenetic comparative study assessing the evolutionary determinants of egg size in the moth family Geometridae. These moths were found to show a strong negative allometric relationship between egg size and maternal body size. Using recently developed comparative methods based on an Ornstein-Uhlenbeck process, we show that maternal body size explains over half the variation in egg size. However, other determinants are less clear: ecological factors, previously hypothesized to affect egg size, were not found to have a considerable influence in the Geometridae. The limited role of such third factors suggests a direct causal link between egg size and body size rather than an indirect correlation mediated by some ecological factors. Notably, no large geometrid species lay small eggs. This pattern suggests that maternal body size poses a physical constraint on egg size, but within these limits, there appears to be a rather invariable selection for larger eggs.

Videotaping small groups of students in a regular classroom environment makes it possible to study individual student cognitive growth in a social setting. The present report deals with student development of some new mathematical ideas over an extended period of time.

Reflection and refraction of magneto-elastic waves at the interface of two ferromagnetic half-spaces is considered. The space is in an external homogeneous magnetic field, the direction of which coincides with direction of the initial magnetization vector. A slipping contact on the interface of two ferromagnetic semi-spaces is considered. The existence of new type of waves is shown. These waves are localized on the interface of two ferromagnetic media and accompany the reflection and transmission waves and exist because of incident waves on the interface of two magneto-elastic media, and magneto-elastic properties of the media. These types of waves named as an accompanying surface magnetoelastic (ASM) waves. An analytical expression for the magnitudes of reflection, refraction, and ASM waves are derived. Coefficients of mentioned waves are strongly dependent on the applied magnetic field, material properties of each medium, as well as on frequency and the angle of an incident elastic wave. It has been shown that an applied magnetic field can totally eliminate or strengthen transmission and reflection waves and can be a control parameter for exchanging energies between these waves. Also, by eliminating transmission and reflection waves the magnetic field is able to control the ASM wave magnitudes. A new wave filtration mechanism can be drawn from these effects.Copyright © 2009 by ASME

A FORTRAN program is given for calculating the average run length (ARL) of a zone control chart with zone scores specified by the user. The program has two parts. The first part of the program allo...

The myoD gene converts many differentiated cell types into muscle. MyoD is a member of the basic-helix-loop-helix family of proteins; this 68-amino acid domain in MyoD is necessary and sufficient for myogenesis. MyoD binds cooperatively to muscle-specific enhancers and activates transcription. The helix-loop-helix motif is responsible for dimerization, and, depending on its dimerization partner, MyoD activity can be controlled. MyoD senses and integrates many facets of cell state. MyoD is expressed only in skeletal muscle and its precursors; in nonmuscle cells myoD is repressed by specific genes. MyoD activates its own transcription; this may stabilize commitment to myogenesis.

A BASIC program is given for determining the required sample size and the upper control limit for an S-chart with two average run length (ARL) constraints. The program may be used in cases where th...

OBJECTIVE—To study whether obese individuals, who are at higher risk for diabetes and disparities in care than nonobese individuals, are more likely to have undiagnosed diabetes. RESEARCH DESIGN AND METHODS—We performed an analysis of 5,514 adult participants in the 1999–2004 National Health and Nutrition Examination Survey. Particpants were interviewed about sociodemographic and medical data, including whether they had been diagnosed with diabetes, and were examined for height, weight, and fasting plasma glucose level ≥126 mg/dl or by previous physician diagnosis. After categorizing participants into normal weight, overweight, and obese according to BMI, the prevalance and diagnosis of diabetes across BMI categories was compared using χ2. RESULTS—Of the 9.8% (weighted sample) of participants who had diabetes, based on fasting glucose levels and self-reported diagnosis, 28.1% were undiagnosed, translating to an estimated 5.2 million people in the U.S. population. The proportion undiagnosed was not significantly different among normal-weight (22.2%), overweight (32.5%), or obese adults (27.4%). Nevertheless, obese adults comprise more than half of the undiagnosed diabetes cases (2.7 million). Relative to normal-weight adults, the adjusted odds ratio (OR) for having undiagnosed diabetes was 1.50 (0.73–3.08) in overweight and 1.37 (0.72–2.63) in obese adults. CONCLUSIONS—Despite a higher underlying risk of diabetes and widespread clinical recognition of this higher risk, obesity does not increase the likelihood that an individual's diabetes will be diagnosed.

Average run lengths of the zone control chart are presented, The performance of this chart is compared with that of several Shewhart charts with and without runs rules, It is shown that the standard zone control chart has performance similar to some even simpler charts and a much higher false alarm rate than the Shewhart chart with all of the common runs rules. It is also shown that a slightly modified zone control chart outperforms the Shewhart chart with the common runs rules.

I would answer an unequivocal “yes!“, for at least two reasons. First, as van Oers (this issue) points out, theories do determine curricula and teaching practices, although it is important to recognize that the theories that shape actual school practice are nearly always informal, naive, unexamined, implicit theories that often bear only modest resemblance to the more formal theories presented in the literature. Even people who may claim that they have no theory whatsoever undoubtedly do; they are merely confessing to an unexamined implicit theory (Davis, 1987). Second, in addition to pointing us in correct directions, a good theory is one that gives us tools to think with. In this regard, not all theories are equal. We can reason better with certain kinds of symbols than we can with others, a point I shall return to later when I consider the problem about mixing wine and water. In general, the more tangible and definite a symbol is, the more easily and powerfully we can reason with it. I am not sure that the experience of different nations is exactly the same. At the level of schools and teachers (which is the level that really counts) there seem to be two dominant theories in the United States today. The first is the theory of ‘direct teaching’ (sometimes attributed to Madeleine Hunter), which argues for a highly-explicit identification of what you want students to learn, a very clear exposition of this information, considerable drill

Electronic devices based on single crystal SiC represent a good choice for a variety of new high temperature, high power electronics applications. The challenge is to develop a package that is resistant to thermal degradation in harsh environments. Conditions are extreme and this all but rules out only a handful of materials and materials systems. Polycrystalline SiC is the material that we have chosen to study as a suitable package and materials suitability/compatibility has been considered on several levels.

A study on a 220-piece corpus (baroque, classical, romantic, 12-tone, jazz, rock, DNA strings, and random music) reveals that aesthetically pleasing music may be describable under the Zipf-Mandelbrot law. Various Zipf-based metrics have been developed and evaluated. Some focus on music-theoretic attributes such as pitch, pitch and duration, melodic intervals, and harmonic intervals. Others focus on higher-order attributes and fractal aspects of musical balance. Zipf distributions across certain dimensions appear to be a necessary, but not sufficient condition for pleasant music. Statistical analyses suggest that combinations of Zipf-based metrics might be used to identify genre and/or composer. This is supported by a preliminary experiment with a neural network classifier. We describe an evolutionary music framework under development, which utilizes Zipf-based metrics as fitness functions.

Sexual risk-taking research and subsequent intervention programs have focused almost exclusively on adolescents and men who have sex with men. In comparison, less research has been conducted into adult heterosexual risk-taking behavior. The purposes of this pilot study were to test a survey instrument, assess how low-income adults perceive their risk of human immunodeficiency virus (HIV) and sexually transmitted disease (STD) infection, and determine the degree to which condom use is a function of age. The Health Belief Model was used to guide the development of the survey instrument. In the Health Belief Model, age is a mediating factor that influences a person's likelihood to take action to change his or her lifestyle. Respondents perceived that their vulnerability to infection declined because of increased age and decreased frequency of coitus. Condom use was found to significantly decline as the age of the respondents increased. Although this is only a pilot study, the findings highlight the need for HIV and STD education for all age groups and genders.

As new nations form out of the wreckage of the Soviet Empire, they will be encumbered by the persistent political, economic, and social problems that have plagued this region for centuries. Today, the leaders of the emerging central Eurasian area are focused solely on political and economic concerns. They are paying little attention to the drug use that, like the more traditional heavy alcohol use, is a means by which many people of this region escape the reality and manifold uncertainties of today's world. If and when the political and economic climate of the central Eurasian area stabilizes, regional leaders will face an addiction problem that will have, by then, become the region's greatest obstacle to social progress and sound public health.

"Every theory," Albert Einstein once said, "should be as simple as possible, but no simpler." We argue here that those of us who study the learning and teaching of mathematics are handicapped by encounters with theories that are, indeed, simpler than the allowable minimum. The antidote, we argue, consists of two necessary steps: careful observation of the details of people who are dealing with mathematical situations of various sorts, and the postulation of somewhat more elaborated theories.