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points in mind, you should be able to coordinate the spoken text of your presentation with the visual content you will show. This will help you create the most effective and informative arrangement of materials for your audience. Just as any good piece of writing is built around the framework of a Beginning, Middle, and End, so too are good |
presentations structured along a clear, three-part outline. Organize your presentation into corresponding sections: In each part of your presentation, try to bring in concepts that you have just discussed, as well as forecasting to later points within your talk. This will stimulate your audience and offer the sense that they are participating with you through the well organized structure of |
the presentation. Grabbing Hold of the Audience’s Attention Organization and use of varied materials is key to creating a good presentation. Typically, an audience loses interest after about 15 minutes, irrespective of the topic being discussed. To combat this loss of attention, change the format of your presentation every 15 minutes in order to encourage new interest and bring the |
audience into a participatory (not passive) mode with you. Engage your audience with varied audiovisual material, such as PowerPoint slides that switch from static images to audio or video. Allow “open spaces” for your audience to consider questions, self-tests, and brainstorming that involve them. Alternate the graphics content you show, from case studies and charts to engaging images related to |
your research, or video or audio content that supports your topic. When making slides, simplicity is the most important concept to keep in mind. The choice of color, typeface (font), and content can significantly alter the effectiveness of slide presentations. In order for your slides to be effective, they should be pertinent, understandable, interesting, and legible. Create slides that enhance |
your discussion rather than detract from it. Determine the basic structure of your slides. This decision greatly affects the legibility of your slides. The “slide master” feature in your software program can create a consistent slide design for all of the slides in your presentation. Color scheme is a crucial design element for producing effective slides. Slides used by presenters |
may be colorful and striking . . . but they can also be unreadable: the greater the number of colors used per slide, the more likely it is that each slide will be difficult to read. The color scheme you choose for your slides should include selections for background, main title, subtitles, text, and highlighted text. Remember: the more contrast |
between text and background, the easier your slides will be to read. Other important design elements are graphic elements and transitions. Analysis The following slide uses color more effectively for contrast, allowing for less distraction. Font Analysis These problems are corrected on the following slide. Slide Content Analysis Choose a typeface (font) that will make your slides legible. To test |
if the font size is sufficient, stand six feet from your monitor to see if you can read your slides. Your slides will never cover as much information as your spoken text. Too many slides, containing excessively complex (often illegible) information, will make for an unsuccessful presentation. Remember that lectures allow the presenter to synthesize information into broad concepts; the |
details can be presented in handouts for the audience to read at a later time. The following slide uses color more effectively for contrast, allowing for less distraction. These problems are corrected on the following slide. Graphs and Charts Graphics should be large and simple enough for the audience to quickly comprehend important concepts being depicted. Avoid clutter by eliminating |
all unnecessary items. As visible in the second slide above, the outlier of two seizures at six hours is much easier to see from the graph than from the first table, which presents only numbers in a grid. Below is a one-dimensional bar graph that is much more legible. About 95% of communication is nonverbal, and your delivery skills can |
either enhance a lecture or detract from it. Try to use the following techniques to keep listeners interested in what you have to say: Alley, Michael. The Craft of Scientific Presentations. Springer-Verlag, NY, 2003. Kroodsma DE, Byers BE. Suggestions for slides at scientific meetings. Reynolds, Garr. Presentation Zen. New Riders, Berkeley, CA, 2008.Author Disclosure Dr. Scherokman has nothing to disclose. |
Marion City Library will have a program about “Oceans in Kansas” at 7 p.m. Tuesday. Michael Everhart of the Kansas Humanities Council will talk about how Kansas has been the source of many important fossils. From giant marine reptiles to flying reptiles and birds with teeth, many important discoveries of now-extinct species came from rocks in western Kansas. Everhart’s presentation will take the audience |
back to a time when the state was covered by an ocean and ruled by giant marine reptiles larger than most dinosaurs. The public is encouraged to bring any fossils they may have for Everhart to look at and describe. For more information, call Marion City Library at (620) 382-2442. |
There are many plant genera that have long been considered to involve extensive hybridization, as indeed there are also for vertebrates (eg. Lepus, Salmo). These genera form complexes of taxa that apparently intergrade due to individuals that are phenotypically and genotypically intermediate. One such plant genus is Nicotiana (tobacco). In |
1954 Thomas Harper Goodspeed published a summary of his lifetime's work on this genus, consolidating his data concerning morphology, cytology, genetics, distribution and taxonomy. While this work was not universally well received, especially the taxonomy (eg. DeWolf 1957), it does contain one interesting diagram, which is an evolutionary network summarizing |
his ideas on the phylogeny of the genus. Since the relationships are complex, so is the diagram. However, basically, Part A summarizes the relationships among some of the species, while Part B summarizes the rest along with "centroids" representing the species from Part A. The different orbital rings represent hypothetical |
ancestors of the various groups, with the groups having different numbers of chromosomes. As Knapp et al. (2004) have noted: "Amphidiploid (allotetraploid) hybridization is common in the genus and appears to be unrelated to human intervention; both the tobaccos of commerce as well as several other species and species groups |
are amphidiploid hybrids." An amphidiploid is an interspecific hybrid having a complete diploid chromosome set from each parent. It is this hybridization that creates the complexity among the tobacco taxa, and its nature is summarized by Chase et al. (2003). Goodpseed's hybridization network is a fascinating early attempt to represent |
evolutionary complexity, irrespective of what one thinks about his methodology, which is never satisfactorily explained. The existence of subjectively determined hypothetical ancestors is probably the most worrisome aspect. However, apart from drawing attention to the existence of the network, I wish to raise a point about how to turn this |
complexity into a classification. Goodspeed (1947) had a go at this, as did Goodspeed (1954). However, more importantly Knapp et al. (2004) made a more recent attempt, and they had this to say: We retain Goodspeed's sectional classification as the basic framework for this new classification, understanding that different ways |
of treating hybrids in phylogenetic classifications have been proposed. In this sectional classification we have placed all amphidiploid species in sections separate from their progenitor taxa because they represent fusion of two distinct genomes, and based on studies such as Kenton & al. (1993) we know that these genomic interactions |
create new traits and permit movement into new habitats.The classification is based on a phylogenetic tree onto which the authors have plotted reticulations representing hybridization (see below). Those taxonomic sections that are represented in the tree-like parts of the phylogeny can thereby be considered to be monophyletic, but those sections |
consisting of hybrids cannot. |Summary of the classification of Nicotiana, showing diploid species and their sectional classification.| Sections of allotetraploid origin are indicated by dashed lines from both of their parental lineages. My question is this: Is this really the best way of treating hybrids taxonomically? It looks a bit |
like an attempt to sweep all of the problems together into separate piles, and then simply labelling them "problem piles". Mind you, in this particular example all of the hybrids in any one section are hypothesized to have had the same lineages as parents, so there is some coherence to |
each section. However, unless we hypothesize a single hybrid origin for each section the component species cannot be considered to have a unique common ancestor, which all of the non-hybrid sections do have. In this sense the sections are not directly comparable. Chase M.W., Knapp S., Cox A.V., Clarkson J.J., |
Butsko Y., Joseph J., Savolainen V., Parokonny A.S. (2003) Molecular systematics, GISH and the origin of hybrid taxa in Nicotiana (Solanaceae). Annals of Botany 92: 107-127. DeWolf G.P. (1957) Review of Goodspeed (1954). The Southwestern Naturalist 2: 177-179. Goodspeed T.H. (1947) On the evolution of the genus Nicotiana. Proceedings of |
the National Academy of Sciences of the USA 33: 158-171. Goodspeed T.H. (1954) The genus Nicotiana: origins, relationships and evolution of its species in the light of their distribution, morphology and cytogenetics. Chronica Botanica 16: 1-536. Knapp S., Chase M.W., Clarkson J.J. (2004) Nomenclatural changes and a new sectional classification |
Virtual phonons get real Dec 3, 2012 4 comments An acoustic analogue of the dynamical Casimir effect (DCE) has been demonstrated for the first time. Carried out by physicists in France, the experiment involves converting quantum fluctuations into pairs of quantized sound waves – or phonons – in an ultracold atomic gas. The experimental system could boost our understanding of |
how radiation emerges spontaneously from a vacuum. Indeed, the team is keen on modifying the set-up so it could be used to simulate Hawking radiation, a type of spontaneous vacuum radiation that is created at the edge of black holes. One of the more peculiar aspects of quantum mechanics is that the vacuum is never truly empty. Instead it contains |
a small amount of energy and is buzzing with particles that appear out of nothingness, only to vanish again. One famous consequence of this is the Casimir force, where two parallel mirrors positioned close together in a vacuum experience an attractive force. While the force was first proposed in 1948 by the Dutch physicist Hendrik Casimir, it is so small |
that it was not measured in the lab until 1997. Separating virtual particles In 1970 the American physicist Gerald Moore proposed the dynamical Casimir effect, which builds on Casimir's original mirror system and shows how these virtual photons could be converted into real photons. The idea is that the phase of an electromagnetic wave goes to zero at the surface |
of a mirror. However, if the mirror is accelerated to a significant fraction of the speed of light, the electromagnetic field does not have time to adjust. The result is that the mirror can separate the virtual particles before they annihilate – keeping them in existence long enough to be detected. However, accelerating the mirrors to these speeds in the |
laboratory has so far proved impossible. To get around this problem, Chris Wilson and colleagues at Chalmers University used a superconducting quantum interference device (SQUID) as an oscillating mirror – and in 2011 they claimed the first demonstration of the DCE in the laboratory. Now Chris Westbrook and colleagues at the Charles Fabry Laboratory at the University of Paris-Sud say |
they have created the first acoustic analogue to the DCE – which involves virtual phonons rather than photons. Their experiment was inspired by theoretical work done in 2010 by Iacopo Carusotto of Italy's University of Trento and colleagues. The Italian physicists argued that an acoustic dynamical Casimir effect should be seen in a Bose–Einstein condensate (BEC) when there is a |
rapid change in the scattering length that governs how its constituent atoms interact. A BEC is formed when identical bosons – particles with integer spin – are cooled until all particles are in the same quantum state. BECs are a good place to look for quantum effects because their extremely low temperature minimizes the effects of thermal noise. Changing the |
speed of sound The team created its BEC by cooling about 100,000 helium atoms to about 200 nK. Instead of changing the scattering length, the team found it could achieve the DCE by changing the speed of sound within the BEC. This was done by squeezing the BEC through rapidly increasing the intensity of the laser that traps the atoms. |
This compression causes virtual phonons to become pairs of real phonons that propagate in opposite directions. These phonons cannot be detected directly. Instead the physicists switch off the laser and then measure the velocity of the atoms as they leave the cloud. This showed that excitations with equal and opposite momenta were moving through the BEC – excitations that were |
not seen when the BEC was not squeezed. "Before I started doing this, I had heard of [the dynamic Casimir effect] and it sounded...unfathomably complicated," says Westbrook. "Doing this shows that it is not. It is a concrete illustration of what can happen. And once you can get your mind around it you can start modifying the conditions and thinking |
about other things [like] Hawking radiation." Gobbling up sound In 2009 Jeff Steinhauer and colleagues at the Israel Institute of Technology in Haifa produced an acoustic analogue to a black hole, which gobbles up sound instead of light. Westbrook says the team is particularly interested in combining the two systems to eventually create an acoustic analogue to Hawking radiation, a |
type of spontaneous vacuum radiation that takes place near the edge of black holes. One potential flaw of the new experiment is that the DCE is seeded by thermal noise in the BEC – not by quantum vacuum fluctuations. This is because even at a chilly 200 nK, thermal effects are significant and therefore it could be argued that this |
experiment does not demonstrate the "pure" dynamical Casimir effect. Steinhauer agrees that the goal should be to detect correlated phonons that are seeded by quantum fluctuations. But he says the research is a "good step" toward that goal. Daniele Faccio at Heriot Watt University in Edinburgh, UK, agrees that the most important next step is for the team to lower |
the temperature of the BEC. However, Faccio says he feels that the current work is still a demonstration of the physics of the DCE. "It is still a spontaneous emission of radiation, and it is a spontaneous emission that is being generated by a periodic changing boundary condition. So the physics are there," says Faccio. "I think it is a |
What Is S.A.F.E.? The Student Awareness of Fire Education (S.A.F.E.) Program is a state initiative to provide resources to local fire departments to conduct fire and life safety education programs in grades K-12. The mission is to enable students to recognize the dangers of fire and more specifically the fire |
6 x 9 The University of Chicago Readings in Western Civilization (nine volumes) makes available to students and teachers a unique selection of primary documents, many in new translations. These readings, prepared for the highly praised Western civilization sequence at the University of Chicago, were chosen by an outstanding group of scholars whose experience teaching that course spans almost four |
decades. Each volume includes rarely anthologized selections as well as standard, more familiar texts; a bibliography of recommended parallel readings; and introductions providing background for the selections. Beginning with Periclean Athens and concluding with twentieth-century Europe, these source materials enable teachers and students to explore a variety of critical approaches to important events and themes in Western history. Individual volumes |
and chunking. Learning, which is essential in the architecture, is modelled as the development of a network of nodes (chunks) which are connected in various ways. This can be contrasted with Soar and ACT-R, two other cognitive architectures, which use |
productions for representing knowledge. CHREST has often been used to model learning using large corpora of stimuli representative of the domain, such as chess games for the simulation of chess expertise or child-directed speech for the simulation of children’s development |
of language. In this respect, the simulations carried out with CHREST have a flavor closer to those carried out with connectionist models than with traditional symbolic models. The architecture contains a number of capacity parameters (e.g., capacity of visual short-term |
memory, set at three chunks) and time parameters (e.g., time to learn a chunk or time to put information into short-term memory). This makes it possible to derive precise and quantitative predictions about human behaviour. Models based on CHREST have |
been used, among other things, to simulate data on the acquisition of chess expertise from novice to grandmaster, children’s acquisition of vocabulary, children’s acquisition of syntactic structures, and concept formation. CHREST is developed by Fernand Gobet at Brunel University and |
Peter C. Lane at the University of Hertfordshire. It is the successor of EPAM, a cognitive model originally developed by Herbert Simon and Edward Feigenbaum. - Freudenthal, D., Pine, J. M., & Gobet, F. (2005). Modelling the development of children's |
use of optional infinitives in English and Dutch using MOSAIC. Cognitive Science, 30, 277-310. - Gobet, F., Lane, P. C. R., Croker, S., Cheng, P. C-H., Jones, G., Oliver, I. & Pine, J. M. (2001). Chunking mechanisms in human learning. |
TRENDS in Cognitive Sciences, 5, 236-243. - Gobet, F. & Simon, H. A. (2000). Five seconds or sixty? Presentation time in expert memory. Cognitive Science, 24, 651-682. - Jones, G., Gobet, F., & Pine, J. M. (in press). Linking working |
Developmental Processes and Mechanisms Robert A. Zucker, Ph.D.; John E. Donovan, Ph.D.; Ann S. Masten, Ph.D.; Margaret E. Mattson, Ph.D.; and Howard B. Moss, M.D. ROBERT A. ZUCKER, PH.D., is |
a professor in the Department of Psychiatry and Psychology and director of the Addiction Research Center, University of Michigan, Ann Arbor, Michigan. JOHN E. DONOVAN, PH.D., is an associate professor |
at the Western Psychiatric Institute & Clinic, University of Pittsburgh, Pittsburgh, Pennsylvania. ANN S. MASTEN, PH.D., is the Distinguished McKnight University Professor in the Institute of Child Development, University of |
Minnesota, Minneapolis, Minnesota. MARGARET E. MATTSON, PH.D., is a clinical trials investigator in the Division of Treatment and Recovery Research, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland. HOWARD |
B. MOSS, M.D., is associate director for Clinical and Translational Research, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland. Little information is available on alcohol use in children up |
to age 10, although rates appear to be low. This age-group is not without risk, however. In fact, numerous nonspecific and specific risk factors for subsequent alcohol use are prevalent |
in childhood. Alcohol-nonspecific risk factors include externalizing and internalizing behaviors, as well as environmental and social factors (e.g., stress, physical abuse, or other aspects of social interaction). Nonspecific childhood factors |
(i.e., predictors) are being identified to target specific population subgroups for preventive interventions. These efforts have identified a variety of predictors of drinking onset during childhood or early adolescence that |
predict adolescent and young-adult problem drinking, as well as adult alcohol use and alcohol use disorders. Alcohol-specific risk factors also are being identified, including children’s beliefs and expectancies about alcohol, |
as well as childhood social contexts (e.g., modeling of alcohol use by parents, portrayal of alcohol use in the mass media, and growing up in a family with an alcoholic |
family member). Together, these specific and nonspecific influences play a heavy role in determining a child’s risk of or resilience to later alcohol use and related problems. Key words: Children; |
youth; growth and development; psychological development; underage drinking; alcohol and other drug (AOD) use initiation; AOD use behavior; risk factors; protective factors; environmental factors; social–environmental factors; predictive factors; early AOD |
use onset; AOD expectancies The development of alcohol use behaviors is an ongoing process that lasts through all stages of childhood, adolescence, and young adulthood. Each of these developmental changes |
is associated with particular developmental characteristics as well as with specific risk and protective factors that ultimately impact an individual’s alcohol use and its consequences. This article describes the developmental |
period from birth to the age of 10 and the relevance of that developmental period to the later use and problem use of alcohol. Beginning with an overview of normative |
human development for the age-group (i.e., development that is expected according to generally accepted norms), it then discusses and describes the risk and protective factors related to future use, as |
well as the factors of preadolescence that relate to precocious use. NORMATIVE DEVELOPMENT FOR AGES 0–10: AN OVERVIEW The era from birth to age 10 includes all growth and development |
that occurs from conception through the prenatal experience, infancy, early and middle childhood to the beginnings of adolescence. It is perhaps the most remarkable of all developmental periods for the |
sheer extent of the changes that take place. During this timeframe, the structure, organization, and functions of the brain change dramatically. The fundamental systems for self- and social regulation and |
for adapting to the world develop. The characteristic ways in which individuals regulate their emotions, respond to stress, solve problems, communicate, perceive, learn, and manage their relationships with others develop. |
The child’s “personality” forms. Although change continues throughout life, by age 10, many of the child’s fundamental adaptive systems are in place and are relatively stable. (The developmental periods and |
transitions, key developmental contexts, and developmental tasks and issues for this age-group are summarized in the table.) Key developmental contexts SOURCE: Zucker et al. 2008. ALCOHOL USE IN THE 0–10 |
AGE-GROUP Little information is available on alcohol use in the 0–10 age-group. Surveys of contemporaneous use are exceedingly rare, and retrospective recall by adolescents is not very reliable, with the |
age of first use generally increasing the older the adolescents are when questioned (Engels et al. 1997; Johnson et al. 1997). The little contemporaneous data that exist suggest that alcohol |
use under age 10 is very low but not zero. The Partnership Attitude Tracking Study (PATS), which is sponsored by the Partnership for a Drug-Free America, examines lifetime alcohol use. |
The most recent survey, composed of a national probability sample of almost 2,400 U.S. elementary school students, was conducted in 1999. It found that 9.8 percent of 4th graders (approximately |
age 10), 16.1 percent of 5th graders (approximately age 11), and 29.4 percent of 6th graders (approximately age 12) had taken more than a sip of alcohol in their lives |
more had drunk wine coolers (4.4 percent, 6.7 percent, and 10.3 percent, respectively), and fewer reported drinking liquor in the past year (1.9 percent, 2.8 percent, and 5.2 percent, respectively). |
Although these data are based on a large sample of children from many school districts across the country, they were derived from a convenience sample rather than a representative national |
sample. Consequently, the level of bias contained in these estimates cannot be determined. There is little evidence that children under age 10 experience alcohol abuse or alcohol dependence despite some |
clinical reports and anecdotal stories of childhood alcoholics (Famularo et al. 1985; Gordon 1913). Alcohol problems, as opposed to abuse or dependence, are somewhat more prevalent. Chen and colleagues (1999) |
reported, for example, that 4.8 percent of 5th graders in Baltimore, Maryland, already had experienced one or more problems with alcohol. Figures are not available for 3rd and 4th graders |
but can be expected to be lower. The question of when youth initiate alcohol use is a critical one, because younger ages of onset are associated with an increased likelihood |
of developing both problem drinking in adolescence (Ellickson et al. 2003; Fergusson et al. 1994; Gruber et al. 1996; Hawkins et al. 1997) and alcohol abuse or dependence in adulthood |
(Grant and Dawson 1997; Hingson et al. 2006; Pitkanen et al. 2005). The differential risk between childhood alcohol use (age 12 and under) and early adolescent use (age 13 or |
14) is not yet known, but studies have shown that early alcohol use is associated with problematic drinking in later years. Onset of alcohol use by ages 10–12 also is |
related to a variety of other problematic outcomes in grade 12, including absences from school, drinking and driving, and use of marijuana and other illegal drugs (Gruber et al. 1996). |
The following are several basic themes that frame a useful perspective for understanding the timing, processes, and experiences of the preadolescent time period as they relate to the use and |
problem use of alcohol: Much of what causes alcohol use and abuse in youths is not specific to alcohol but is related to other problems in childhood, such as conduct |
problems, aggressiveness, impulsivity, antisocial personality disorder, and attention problems (Kendler et al. 2003; Tsuang et al. 1998; Zucker 2006). During the birth–to–age-10 timeframe, children learn about alcohol, including what it |
does and who uses it and why. They also develop expectations about its use. All these factors shape when children will use alcohol, under what circumstances, and to what extent. |
If a child under age 10 consumes alcohol, it may affect the child’s developing brain structures and functions, including those related to planning, appetite, reward, and emotional and behavioral control. |
Social–environmental factors play a role in alcohol use, such as the effects of family, peers, school, community, and culture. Social norms, for example, dictate when alcohol use is or is |
not acceptable. The multilevel, dynamic interplay of biological, psychological, and social processes shapes normal development as well as the risk for alcohol use and misuse (Masten 2007). RISK FACTORS IN |
CHILDHOOD THAT ARE NONSPECIFIC TO ALCOHOL USE A number of nonspecific risk factors in the birth–to–age-10 group are related to the early onset of drinking and the development of alcohol |
problems and alcohol use disorders in adolescence or adulthood. These risk factors for subsequent alcohol involvement are nonspecific because they also influence a broad range of other behavioral problems. In |
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