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Objective. This study explores relations between mild parental symptoms of anxiety and depression and the temperament and behavior patterns in preschool age children. Design. Parental report and laboratory observations were collected in a community sample (N = 65) of Head Start and other preschool attendees, ages 3-5 years. Results. Mild parental dysphoria is associated with measures of both child temperament and problem behaviors and these child personality measures vary with parental symptomatology. Mild parental depression was diffusely associated with increased levels of both internalizing and externalizing behavior problems, and with attention and emotion regulatory difficulties in children's temperament. Mild parental anxiety was more circumscribed in its association with child problem behavior but was specifically related to children's temperamental difficulties in attention and emotion regulation. Patterns differentiating association with depression and anxiety symptoms were evident from both parental and observer sources of information. Conclusions. Even mild levels of parental distress may relate to both parental perceptions of child temperament and behavior as well as what is observed by others. [ABSTRACT FROM AUTHOR]

The relationship of sensation-seeking to alcohol use and risk-taking behavior was studied in a sample of college women. Two groups of ten, identified on the basis of extreme high and low scores on the sensation-seeking trait, were selected from a larger pool of participants to complete a self-report assessment of willingness to engage in risky behavior while under the influence of alcohol and to perform a series of driving simulation tasks, both while sober and while intoxicated at the legal limit for driving. It was hypothesized that both groups would be more likely to take risks when intoxicated than when sober, and that high sensation-seekers would take greater risks than low sensation-seekers. Compared to low sensation-seekers, high sensation-seekers reported significantly greater levels of alcohol use and were less likely to perceive danger associated with risky behaviors engaged in while under the influence of alcohol. Self-reported appraisal of willingness to take risks in general was unaffected by the actual sobriety condition of respondents. Risk-taking behavior measured in a driving simulation task was affected by state of intoxication. However, pronounced effects were only found for low sensation-seekers. The personality trait of sensation-seeking appears to play an important mediating role in alcohol use and associated risk-taking behavior in young women. [ABSTRACT FROM AUTHOR]

Molecular biology can be challenging for undergraduate students because it requires visual literacy skills to interpret abstract representations of submicroscopic concepts, structures and processes. The Conceptual-Reasoning-Mode framework suggests that visual literacy relies on applying conceptual knowledge to appropriately reason with the different ways of representing concepts in molecular biology. We used this framework to specifically explore visual literacy related to chromosomes. We conducted 35 semi-structured interviews with students who had taken at least a year of college-level biology courses, and we asked them to sketch chromosomes, interpret an abstract representation of chromosomes, and use the abstract representation to answer a multiple-choice question about meiosis. While many participants used the correct vocabulary to describe chromosome structure and function, probing their visual literacy skills revealed gaps in their understanding. Notably, 97% of participants (34 of 35) held conceptual errors related to chromosome structure and function, which were often only revealed in their sketches or explanations of their sketches. Our findings highlight the importance of scaffolding visual literacy skills into instruction by teaching with a variety of visual models and engaging students in using and interpreting the conventions of abstract representations of chromosomes.

Analogies are used to make abstract topics meaningful and more easily comprehensible to learners. Incorporating simple analogies into STEM classrooms is a fairly common practice, but the analogies are typically generated and explained by the instructor for the learners. We hypothesize that challenging learners to create complex, extended analogies themselves can promote integration of content knowledge and development of critical thinking skills, which are essential for deep learning, but are challenging to teach. In this qualitative study, college biology students (n = 30) were asked to construct a complex analogy about the flow of genetic information using a familiar item. One week later, participants constructed a second analogy about the same topic, but this time using a more challenging item. Twenty participants worked on the challenging analogy in pairs, while the other 10 worked alone. Analysis of the 50 interviews resulted in a novel-scoring scheme, which measured both content knowledge (understanding of biology terms) and critical thinking (alignment of relationships between elements of the analogy). Most participants improved slightly due to practice, but they improved dramatically when working with a partner. The biggest gains were seen in critical thinking, not content knowledge. Having students construct complex, sophisticated analogies in pairs is a high-impact practice that can help students develop their critical thinking skills, which are crucial in academic and professional settings. The discussion between partners likely requires students to justify their explanations and critique their partner's explanations, which are characteristics of critical thinking., (© 2024 International Union of Biochemistry and Molecular Biology.)

Effective spatial visualization and reasoning skills are often credited for students' success in science and engineering courses. However, students enrolled in these science courses are not always exposed to or trained properly on the best ways to utilize models to aid in their learning. Improving spatial visualization techniques with 3D models, such as molecular and DNA modeling kits, is often suggested to facilitate students' ability to conceptualize compounds in two and three dimensions. Here, we investigate what techniques students use to conceptualize 2D representations of various biomolecules with the use of 3D models by interviewing undergraduate students from various natural science and engineering disciplines in task-based, think-aloud sessions. After scoring and analyzing the participant data we explored some of the techniques used among successful scoring participants, including the use of informal models to transition between 2D and 3D. Additional techniques used by students who were able to successfully conceptualize 3D images included starting with smaller, granular details to inductively make conclusions when thinking between two and three dimensions. We find that (1) students who anchor their thinking in 3D models show a deeper level of understanding in initially solving science problems successfully, and (2) proper 3D model use and spatial visualization techniques may improve students' abilities to accurately visualize 2D and 3D representations of molecules in science courses. Our results demonstrate that implementing spatial visualization training to teach students how to effectively use 3D models may improve students' problem-solving techniques in science curricula., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society and Division of Chemical Education, Inc.)

Aneuploidy, or having a disrupted genome, is an aberration commonly found in tumours but rare in normal tissues. It gives rise to proteotoxic stress as well as a stereotypical oxidative shift, which makes these cells sensitive to internal and environmental stresses. Using Drosophila as a model, we investigated the changes in transcription in response to ongoing changes to ploidy (chromosomal instability, CIN). We noticed changes in genes affecting one-carbon metabolism, specifically those affecting the production and use of s-adenosyl methionine (SAM). The depletion of several of these genes has led to cell death by apoptosis in CIN cells but not in normal proliferating cells. We found that CIN cells are particularly sensitive to SAM metabolism at least partly because of its role in generating polyamines. Feeding animals spermine was seen to rescue the cell death caused by the loss of SAM synthase in CIN tissues. The loss of polyamines led to decreased rates of autophagy and sensitivity to reactive oxygen species (ROS), which we have shown to contribute significantly to cell death in CIN cells. These findings suggest that a well-tolerated metabolic intervention such as polyamine inhibition has the potential to target CIN tumours via a relatively well-characterised mechanism.

Visual literacy, which is the ability to effectively identify, interpret, evaluate, use, and create images and visual media, is an important aspect of science literacy. As molecular processes are not directly observable, researchers and educators rely on visual representations (e.g., drawings) to communicate ideas in biology. How learners interpret and organize those numerous diagrams is related to their underlying knowledge about biology and their skills in visual literacy. Furthermore, it is not always obvious how and why learners interpret diagrams in the way they do (especially if their interpretations are unexpected), as it is not possible to "see" inside the minds of learners and directly observe the inner workings of their brains. Hence, tools that allow for the investigation of visual literacy are needed. Here, we present a novel card-sorting task based on visual literacy skills to investigate how learners interpret and think about DNA-based concepts. We quantified differences in performance between groups of varying expertise and in pre- and postcourse settings using percentages of expected card pairings and edit distance to a perfect sort. Overall, we found that biology experts organized the visual representations based on deep conceptual features, while biology learners (novices) more often organized based on surface features, such as color and style. We also found that students performed better on the task after a course in which molecular biology concepts were taught, suggesting the activity is a useful and valid tool for measuring knowledge. We have provided the cards to the community for use as a classroom activity, as an assessment instrument, and/or as a useful research tool to probe student ideas about molecular biology., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 Newman et al.)

Learning molecular biology involves using visual representations to communicate ideas about largely unobservable biological processes and molecules. Genes and gene expression cannot be directly visualized, but students are expected to learn and understand these and related concepts. Theoretically, textbook illustrations should help learners master such concepts, but how are genes and other DNA-linked concepts illustrated for learners? We examined all DNA-related images found in 12 undergraduate biology textbooks to better understand what biology students encounter when learning concepts related to DNA. Our analysis revealed a wide array of DNA images that were used to design a new visual framework, the DNA Landscape, which we applied to more than 2000 images from common introductory and advanced biology textbooks. All DNA illustrations could be placed on the landscape framework, but certain positions were more common than others. We mapped figures about "gene expression" and "meiosis" onto the landscape framework to explore how these challenging topics are illustrated for learners, aligning these outcomes with the research literature to showcase how the overuse of certain representations may hinder, instead of help, learning. The DNA Landscape is a tool to promote research on visual literacy and to guide new learning activities for molecular biology.

Reformed Experimental Activities (REActivities) is an innovative approach to the delivery of the traditional material in an undergraduate organic chemistry laboratory. To better understand the fidelity of implementing this pedagogy and what effects the framework of REActivities has on student-instructor interactions, an observational protocol study was employed. This paper also describes the Evaluation of Lab Instructor Time and Engagement (ELITE) observational instrument developed to evaluate instructional behaviors in a lab setting. The instrument was used in first semester undergraduate organic chemistry laboratories across seven universities to measure the robustness of the guided-inquiry materials when implemented and the nature of the instructor's interactions. The ELITE data was analyzed for laboratories delivered using REActivities and compared with expert delivery as well as with traditional expository methods. The data revealed that instructor behaviors when using REActivities were consistent and comparable and could be distinguished from traditional lab deliveries. The nature of the instructor's behaviors also showed a remarkably consistent trend for coded conceptual-based discussion when REActivities was employed, in contrast to the near absence of similar interactions when expository methods were employed for comparable laboratories., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society and Division of Chemical Education, Inc.)

Many biology students struggle to learn about the process of meiosis and have particular difficulty understanding the molecular basis of crossing over and the importance of homologous pairing for proper segregation. To help students overcome these challenges, we designed an activity that uses a newly developed Chromosome Connections Kit® from 3-D Molecular Designs to allow learners to explore meiosis at the molecular level. We took a backwards design approach in constructing an effective classroom activity. We developed evidence-based learning objectives and designed a crossing over activity that targets students' misconceptions and key concepts about meiosis. Assessment questions were designed based on the learning objectives and common student misconceptions. The activity consists of three parts: an interactive introductory video, a model-based activity, and reflection questions. The activity was first beta-tested with a small number of students and revised based on feedback. The revised activity was deployed in a mid-level Cell and Molecular Biology course. Analysis of pre-/post-assessment data from students who completed the activity (n = 83) showed strong learning gains on concepts related to ploidy, homology, segregation, and the mechanism and purpose of crossing over. Additionally, students who participated in the activity outperformed nonparticipants on a Genetics assessment about meiosis the following semester., (© 2021 The Authors. Biochemistry and Molecular Biology Education published by Wiley Periodicals LLC on behalf of International Union of Biochemistry and Molecular Biology.)

Concepts of molecular biology and genetics are difficult for many biology undergraduate students to master yet are crucial for deep understanding of how life works. By asking students to draw their ideas, we attempted to uncover the mental models about genes and gene expression held by biology students ( n = 23) and experts ( n = 18) using semistructured interviews. A large divide was identified between novice and expert conceptions. While experts typically drew box-and-line representations and thought about genes as regions of DNA that were used to encode products, students typically drew whole chromosomes rather than focusing on gene structure and conflated gene expression with simple phenotypic outcomes. Experts universally described gene expression as a set of molecular processes involving transcription and translation, whereas students often associated gene expression with Punnett squares and phenotypic outcomes. Follow-up survey data containing a ranking question confirmed students' alignment of their mental models with the images uncovered during interviews ( n = 156 undergraduate biology students) and indicated that Advanced students demonstrate a shift toward expert-like thinking. An analysis of 14 commonly used biology textbooks did not show any relationship between Punnett squares and discussions of gene expression, so it is doubtful students' ideas originate directly from textbook reading assignments. Our findings add to the literature about mechanistic reasoning abilities of learners and provide new insights into how biology students think about genes and gene expression.

Topics related to energy transformation and metabolism are important parts of an undergraduate biology curriculum, but these are also topics that students traditionally struggle with. To address this, we have created a short online Interactive Video Vignette (IVV) called To Ferment or Not to Ferment: That is the Question . This IVV is designed to help students learn important ideas related to cellular respiration and metabolism. Students in various courses across four institutions were assigned the IVV as an out-of-class preinstruction homework assignment. To test the effectiveness of this IVV on student learning, we collected and analyzed data from questions embedded in the IVV, open response reflection questions, and pre- and postassessments from IVV watchers and nonwatchers. Our analysis revealed that students who completed the IVV activity interacted productively with this online tool and made significant learning gains on important topics related to cellular respiration and metabolism. This IVV is freely available via https://www.rit.edu/cos/interactive/MINT for instructors to adopt for class use., (©2020 Author(s). Published by the American Society for Microbiology.)

Alterations from the normal set of chromosomes are extremely common as cells progress toward tumourigenesis. Similarly, we expect to see disruption of normal cellular metabolism, particularly in the use of glucose. In this review, we discuss the connections between these two processes: how chromosomal aberrations lead to metabolic disruption, and vice versa. Both processes typically result in the production of elevated levels of reactive oxygen species, so we particularly focus on their role in mediating oncogenic changes.

Genomic instability is a common feature of tumours that has a wide range of disruptive effects on cellular homeostasis. In this review we briefly discuss how instability comes about, then focus on the impact of gain or loss of DNA (aneuploidy) on oxidative stress. We discuss several mechanisms that lead from aneuploidy to the production of reactive oxygen species, including the effects on protein complex stoichiometry, endoplasmic reticulum stress and metabolic disruption. Each of these are involved in positive feedback loops that amplify relatively minor genetic changes into major cellular disruption or cell death, depending on the capacity of the cell to induce antioxidants or processes such as mitophagy that can moderate the disruption. Finally we examine the direct effects of reactive oxygen species on mitosis and how oxidative stress can compromise centrosome number, cytoskeletal integrity and signalling processes that are vital for mitotic fidelity.

The essence of molecular biology education lies in understanding of gene expression, with subtopics including the central dogma processes, such as transcription and translation. While these concepts are core to the discipline, they are also notoriously difficult for students to learn, probably because they cannot be directly observed. While nearly all active learning strategies have been shown to improve learning compared with passive lectures, little has been done to compare different types of active learning. We hypothesized that physical models of central dogma processes would be especially helpful for learning, because they provide a resource that students can see, touch, and manipulate while trying to build their knowledge. For students enrolled in an entirely active-learning-based Cell & Molecular Biology course, we examined whether model-based activities were more effective than non-model based activities. To test their understanding at the beginning and end of the semester, we employed the multiple-select Central Dogma Concept Inventory (CDCI). Each student acted as their own control, as all students engaged in all lessons yet some questions related to model-based activities and some related to clicker questions, group problem-solving, and other non-model-based activities. While all students demonstrated learning gains on both types of question, they showed much higher learning gains on model-based questions. Examining their selected answers in detail showed that while higher performing students were prompted to refine their already-good mental models to be even better, lower performing students were able to construct new knowledge that was much more consistent with an expert's understanding. © 2018 The Authors. Biochemistry and Molecular Biology Education published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology., 46(5):435-444, 2018., (© 2018 The Authors. Biochemistry and Molecular Biology Education published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology.)

Since 2009, the U.S. National Science Foundation Directorate for Biological Sciences has funded Research Coordination Networks (RCN) aimed at collaborative efforts to improve participation, learning, and assessment in undergraduate biology education (UBE). RCN-UBE projects focus on coordination and communication among scientists and educators who are fostering improved and innovative approaches to biology education. When faculty members collaborate with the overarching goal of advancing undergraduate biology education, there is a need to optimize collaboration between participants in order to deeply integrate the knowledge across disciplinary boundaries. In this essay we propose a novel guiding framework for bringing colleagues together to advance knowledge and its integration across disciplines, the "Five 'C's' of Collaboration: Commitment, Collegiality, Communication, Consensus, and Continuity." This guiding framework for professional network practice is informed by both relevant literature and empirical evidence from community-building experience within the RCN-UBE Advancing Competencies in Experimentation-Biology (ACE-Bio) Network. The framework is presented with practical examples to illustrate how it might be used to enhance collaboration between new and existing participants in the ACE-Bio Network as well as within other interdisciplinary networks.

In this article, we begin to unpack the phenomenon of representational competence by exploring how arrow symbols are used in introductory biology textbook figures. Out of 1214 figures in an introductory biology textbook, 632 (52%) of them contained arrows that were used to represent many different concepts or processes. Analysis of these figures revealed little correlation between arrow style and meaning. A more focused study of 86 figures containing 230 arrows from a second textbook showed the same pattern of inconsistency. Interviews with undergraduates confirmed that arrows in selected textbook figures were confusing and did not readily convey the information intended by the authors. We also present findings from an online survey in which subjects were asked to infer meaning of different styles of arrows in the absence of context. Few arrow styles had intrinsic meaning to participants, and illustrators did not always use those arrows for the meanings expected by students. Thus, certain styles of arrows triggered confusion and/or incorrect conceptual ideas. We argue that 1) illustrators need to be more clear and consistent when using arrow symbols, 2) instructors need to be cognizant of the level of clarity of representations used during instruction, and 3) instructors should help students learn how to interpret representations containing arrows., (© 2018 L. K. Wright et al. CBE—Life Sciences Education © 2018 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).)

Although instruction on meiosis is repeated many times during the undergraduate curriculum, many students show poor comprehension even as upper-level biology majors. We propose that the difficulty lies in the complexity of understanding DNA, which we explain through a new model, the DNA triangle The DNA triangle integrates three distinct scales at which one can think about DNA: chromosomal , molecular , and informational Through analysis of interview and survey data from biology faculty and students through the lens of the DNA triangle, we illustrate important differences in how novices and experts are able to explain the concepts of ploidy , homology , and mechanism of homologous pairing Similarly, analysis of passages from 16 different biology textbooks shows a large divide between introductory and advanced material, with introductory books omitting explanations of meiosis-linked concepts at the molecular level of DNA. Finally, backed by textbook findings and feedback from biology experts, we show that the DNA triangle can be applied to teaching and learning meiosis. By applying the DNA triangle to topics on meiosis we present a new framework for educators and researchers that ties concepts of ploidy, homology, and mechanism of homologous pairing to knowledge about DNA on the chromosomal, molecular, and informational levels., (© 2017 L. K. Wright et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).)

We report observations from the Magnetospheric Multiscale (MMS) satellites of the electron jet in a symmetric magnetic reconnection event with moderate guide field. All four spacecraft sampled the ion diffusion region and observed the electron exhaust. The observations suggest that the presence of the guide field leads to an asymmetric Hall field, which results in an electron jet skewed towards the separatrix with a nonzero component along the magnetic field. The jet appears in conjunction with a spatially and temporally persistent parallel electric field ranging from -3 to -5  mV/m, which led to dissipation on the order of 8  nW/m^{3}. The parallel electric field heats electrons that drift through it, and is associated with a streaming instability and electron phase space holes.

We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E_{∥}) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E_{∥} events near the electron diffusion region have amplitudes on the order of 100  mV/m, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E_{∥} events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E_{∥} events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.

Scientific teaching requires scientifically constructed, field-tested instruments to accurately evaluate student thinking and gauge teacher effectiveness. We have developed a 23-question, multiple select-format assessment of student understanding of the essential concepts of the central dogma of molecular biology that is appropriate for all levels of undergraduate biology. Questions for the Central Dogma Concept Inventory (CDCI) tool were developed and iteratively revised based on student language and review by experts. The ability of the CDCI to discriminate between levels of understanding of the central dogma is supported by field testing (N= 54), and large-scale beta testing (N= 1733). Performance on the assessment increased with experience in biology; scores covered a broad range and showed no ceiling effect, even with senior biology majors, and pre/posttesting of a single class focused on the central dogma showed significant improvement. The multiple-select format reduces the chances of correct answers by random guessing, allows students at different levels to exhibit the extent of their knowledge, and provides deeper insight into the complexity of student thinking on each theme. To date, the CDCI is the first tool dedicated to measuring student thinking about the central dogma of molecular biology, and version 5 is ready to use., (© 2016 D. L. Newman et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).)

The current study presents the implementation of a set of school based interventions in a greater New Orleans school district one year following Hurricane Katrina. The interventions included adaptation and implementation of evidence based treatments in a crisis situation with at-risk youth which involved training and clinical challenges. 386 students found to have significant depressive and/or disruptive disorder symptoms received treatment from the School Therapeutic Enhancement Program (STEP). Further, a district-wide mental health needs assessment of middle and high school students (N = 11,861) screened for behavioral and emotional difficulties at the beginning and end of the school year provided a benchmark for community youth's emotional and behavioral distress. High-need intervention students demonstrated clinically significant lower levels of emotional and behavioral problems, depression and inattention in comparison to pre-treatment levels as indicated by multiple informants (i.e., self, parent, teacher). Self-reported distress levels were also lower than screening group students at post-test. These findings support the efficacy of a school-based intervention for youth struggling with the aftereffects of a highly disruptive natural disaster. Implications for utilizing a flexible adaptation of an evidence-based training model involving coaching and consultation are discussed.

The central dogma of molecular biology, a model that has remained intact for decades, describes the transfer of genetic information from DNA to protein though an RNA intermediate. While recent work has illustrated many exceptions to the central dogma, it is still a common model used to describe and study the relationship between genes and protein products. We investigated understanding of central dogma concepts and found that students are not primed to think about information when presented with the canonical figure of the central dogma. We also uncovered conceptual errors in student interpretation of the meaning of the transcription arrow in the central dogma representation; 36% of students (n = 128; all undergraduate levels) described transcription as a chemical conversion of DNA into RNA or suggested that RNA existed before the process of transcription began. Interviews confirm that students with weak conceptual understanding of information flow find inappropriate meaning in the canonical representation of central dogma. Therefore, we suggest that use of this representation during instruction can be counterproductive unless educators are explicit about the underlying meaning., (© 2014 L. K. Wright et al. CBE—Life Sciences Education © 2014 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).)

Kinetic simulations of magnetotail reconnection have revealed electromagnetic whistlers originating near the exhaust boundary and propagating into the inflow region. The whistler production mechanism is not a linear instability, but rather is Čerenkov emission of almost parallel whistlers from localized moving clumps of charge (finite-size quasiparticles) associated with nonlinear coherent electron phase space holes. Whistlers are strongly excited by holes without ever growing exponentially. In the simulation the whistlers are emitted in the source region from holes that accelerate down the magnetic separatrix towards the x line. The phase velocity of the whistlers vφ in the source region is everywhere well matched to the hole velocity vH as required by the Čerenkov condition. The simulation shows emission is most efficient near the theoretical maximum vφ=half the electron Alfven speed, consistent with the new theoretical prediction that faster holes radiate more efficiently. While transferring energy to whistlers the holes lose coherence and dissipate over a few local ion inertial lengths. The whistlers, however, propagate to the x line and out over many 10's of ion inertial lengths into the inflow region of reconnection. As the whistlers pass near the x line they modulate the rate at which magnetic field lines reconnect.

We present a PCR-based laboratory exercise that can be used with first- or second-year biology students to help overcome common misconceptions about gene expression. Biology students typically do not have a clear understanding of the difference between genes (DNA) and gene expression (mRNA/protein) and often believe that genes exist in an organism or cell only when they are expressed. This laboratory exercise allows students to carry out a PCR-based experiment designed to challenge their misunderstanding of the difference between genes and gene expression. Students first transform E. coli with an inducible GFP gene containing plasmid and observe induced and un-induced colonies. The following exercise creates cognitive dissonance when actual PCR results contradict their initial (incorrect) predictions of the presence of the GFP gene in transformed cells. Field testing of this laboratory exercise resulted in learning gains on both knowledge and application questions on concepts related to genes and gene expression.

Age-related hearing impairment (ARHI), or presbycusis, is a common condition of the elderly that results in significant communication difficulties in daily life. Clinically, it has been defined as a progressive loss of sensitivity to sound, starting at the high frequencies, inability to understand speech, lengthening of the minimum discernable temporal gap in sounds, and a decrease in the ability to filter out background noise. The causes of presbycusis are likely a combination of environmental and genetic factors. Previous research into the genetics of presbycusis has focused solely on hearing as measured by pure-tone thresholds. A few loci have been identified, based on a best ear pure-tone average phenotype, as having a likely role in susceptibility to this type of hearing loss; and GRM7 is the only gene that has achieved genome-wide significance. We examined the association of GRM7 variants identified from the previous study, which used an European cohort with Z-scores based on pure-tone thresholds, in a European-American population from Rochester, NY (N = 687), and used novel phenotypes of presbycusis. In the present study mixed modeling analyses were used to explore the relationship of GRM7 haplotype and SNP genotypes with various measures of auditory perception. Here we show that GRM7 alleles are associated primarily with peripheral measures of hearing loss, and particularly with speech detection in older adults., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Cellular processes that rely on knowledge of molecular behavior are difficult for students to comprehend. For example, thorough understanding of meiosis requires students to integrate several complex concepts related to chromosome structure and function. Using a grounded theory approach, we have unified classroom observations, assessment data, and in-depth interviews under the theory of knowledge transfer to explain student difficulties with concepts related to chromosomal behavior. In this paper, we show that students typically understand basic chromosome structure but do not activate cognitive resources that would allow them to explain macromolecular phenomena (e.g., homologous pairing during meiosis). To improve understanding of topics related to genetic information flow, we suggest that instructors use pedagogies and activities that prime students for making connections between chromosome structure and cellular processes.

Previous 2D simulations of reconnection using a standard model of initially antiparallel magnetic fields have detected electron jets outflowing from the x point into the ion outflow exhausts. Associated with these jets are extended "outer electron diffusion regions." New PIC simulations with an ion to electron mass ratio as large as 1836 (an H(+) plasma) now show that the jets are strongly deflected and the outer electron diffusion region is broken up by a very weak out-of-plane magnetic guide field, even though the diffusion rate itself is unchanged. Jet outflow and deflection are interpreted in terms of electron dynamics and are compared to recent measurements of jets in the presence of a small guide field in Earth's magnetosheath.

Chromosome structure is confusing to students at all levels, and chromosome behavior during meiosis is a notoriously difficult topic. Undergraduate biology majors are exposed to the process of meiosis numerous times during their presecondary and postsecondary education, yet understanding of key concepts, such as the point at which haploidy is established, does not improve substantially with repeated exposure. Based on student's drawings, 96% of intermediate-level biology majors have unclear or incorrect ideas about meiosis. Students have difficulty diagramming the process of meiosis starting with three unreplicated pairs of chromosomes, and even when they can produce an accurate diagram, they are unclear how to assign the terms "haploid" and "diploid." We designed an interactive lesson based on constructivist theory to address these issues in a large lecture class. Pretest and posttest scores showed a significant improvement in students' understanding of ploidy compared to a parallel class taught in the traditional way (e.g. using the textbook diagrams). In interviews afterward, those students whose scores improved on exams specifically pointed to the features of the in-class modeling that were deliberately incorporated for that purpose., (Copyright © 2011 Wiley Periodicals, Inc.)

Despite the fact that corporal punishment (CP) is a significant risk factor for increased aggression in children, child physical abuse victimization, and other poor outcomes, approval of CP remains high in the United States. Having a positive attitude toward CP use is a strong and malleable predictor of CP use and, therefore, is an important potential target for reducing use of CP. The Theory of Planned Behavior suggests that parents' perceived injunctive and descriptive social norms and expectations regarding CP use might be linked with CP attitudes and behavior. A random-digit-dial telephone survey of parents from an urban community sample (n = 500) was conducted. Perceived social norms were the strongest predictors of having positive attitudes toward CP, as follows: (1) perceived approval of CP by professionals (β = 0.30), (2) perceived descriptive norms of CP use (β = 0.22), and (3) perceived approval of CP by family and friends (β = 0.19); also, both positive (β = 0.13) and negative (β = -0.13) expected outcomes for CP use were strong predictors of these attitudes. Targeted efforts are needed to both assess and shift the attitudes and practices of professionals who influence parents regarding CP use; universal efforts, such as public education campaigns, are needed to educate parents and the general public about the high risk/benefit ratio for using CP and the effectiveness of non-physical forms of child discipline.

Observations of electron phase-space holes (EHs) in Earth's plasma sheet by the THEMIS satellites include the first detection of a magnetic perturbation (deltaB_{ parallel}) parallel to the ambient magnetic field (B0). EHs with a detectable deltaB_{ parallel} have several distinguishing features including large electric field amplitudes, a magnetic perturbation perpendicular to B0, high speeds ( approximately 0.3c) along B0, and sizes along B0 of tens of Debye lengths. These EHs have a significant center potential (Phi approximately k_{B}T_{e}/e), suggesting strongly nonlinear behavior nearby such as double layers or magnetic reconnection.

We show that observed spatial- and frequency-domain signatures of intense solar-wind Langmuir waves can be described as eigenmodes trapped in a parabolic density well. Measured solar-wind electric field spectra and waveforms are compared with 1D linear solutions and, in many cases, can be represented by 1-3 low-order eigenstates. To our knowledge, this report is the first observational confirmation of Langmuir eigenmodes in space. These results suggest that linear eigenmodes may be the starting point of the nonlinear evolution, critical for producing solar type II and type III radio bursts.

A theoretical model of weak electron phase-space holes is used to interpret bipolar field structures observed in space. In the limit ephi(max)/Te << 1 the potential of the structure has the unique form, phi(x) = phi(max)sech4(x/alpha), where phi(max) depends on the derivative of the trapped distribution at the separatrix, while alpha depends only on a screening integral over the untrapped distribution. Idealized trapped and passing electron distributions are inferred from the speed, amplitude, and shape of satellite waveform measurements of weak bipolar field structures.

American Indian youth may be at increased risk for anxiety-related problems. Social anxiety is the most common form of anxiety experienced by adolescents, yet little research specific to American Indians has been conducted. Childhood temperament, especially behavioral inhibition (BI), has been identified as an important risk factor for social anxiety in other racial and ethnic groups. This study examined BI in relation to social anxiety in a cross-sectional community-based sample of 86 rural southeastern American Indian adolescents. Patterns of childhood BI suggested cultural variations in the way temperament relates to adolescent social anxiety. Specifically, nonsocially based fears in childhood were associated with social anxiety symptoms in adolescence, which is in contrast to previous findings in non American Indian samples that have suggested continuity between social inhibition in childhood and social anxiety in adolescence. It is recommended that major psychological risk factors, including temperament, be evaluated within the specific social and cultural context of the adolescent population of interest., (Copyright 2007 APA)

The dynamic evolution of the boundary between the ionosphere and auroral cavity is studied using 1D and 2D kinetic Vlasov simulations. The initial distributions of three singly ionized species (H+, O+, e-) are determined from space-based observations on both sides of an inferred strong double layer. The kinetic simulations reproduce features of parallel electric fields, electron distributions, ion distributions, and wave turbulence seen in satellite observations in the auroral upward-current region and, for the first time, demonstrate that auroral acceleration can be driven by a parallel electric field supported, in part, by a quasistable, strong double layer. In addition, the simulations verify that the streaming interaction between accelerated O+ and H+ populations continuously replenished by the double layer provides the free energy for the persistent formation of ion phase-space holes.

A genome-wide screen for asthma and atopy susceptibility alleles conducted in the Hutterites, a founder population of European descent, reported evidence of linkage with a short tandem repeat polymorphism (STRP) within the type I interferon (IFN) gene cluster on chromosome 9p21. The goal of this study was to identify variation within the IFN gene cluster that influences susceptibility to asthma and atopic phenotypes. We screened approximately 25 kb of sequence, including the flanking sequence of all 15 functional genes and the single coding exon in 12, in Hutterites representing different IFNA-STRP genotypes. We identified 78 polymorphisms, and genotyped 40 of these (in 14 genes) in a large Hutterite pedigree. Modest associations (0.003

This study examined the utility of the conduct disorder (CD) diagnosis in predicting antisocial personality disorder (ASPD) among incarcerated women. It was surprising that most female inmates did not meet standard criteria for ASPD. This was due to a low occurrence of CD symptoms reported before age 15. Cluster analysis of CD symptoms revealed 4 types that characterized women with criminal histories. One type, which was characterized by a history of CD with interpersonal and physical aggression, was more predictive of ASPD than the traditional CD diagnosis. Yet another type, characterized by destruction of property, also represented an improvement over the traditional CD diagnosis. Overall, the results suggest that the types of CD behaviors, rather than their number, may be a more important indicator for identifying women at risk for future antisocial personality pathology., ((c) 2005 APA, all rights reserved.)

Ethnic identity development was assessed in the context of ego development in 12- to 15-year-old students from a Southeastern American Indian community. Self-protective was the modal level and was characterized by awareness of ethnic group membership but little exploration or self-reflection. Impulsive adolescents had the least developed ethnic identities and highest levels of interpersonal vulnerability. Conformist adolescents expressed positive feelings about ethnic group affiliation, described relationships as harmonious, but demonstrated moderate social anxiety. Postconformist adolescents had the highest levels of agency, social competence, and identity achievement, but also had high levels of psychological distress and family conflict. Adolescent identity strivings may be understood in context with the level and timing of psychosocial maturity, for which ego development appears a useful marker.

Serotonin has been implicated in common disorders involving the central nervous, gastrointestinal, cardiovascular, and pulmonary systems. We describe the first genome-wide screen to identify quantitative trait loci (QTLs) influencing whole blood serotonin in 567 members of a single large pedigree, using a novel association-based mapping approach. We identified an association between the beta3 integrin (ITGB3) Leu33Pro polymorphism on 17q21 and whole blood serotonin levels (P-value = 9.8 x 10(-5)). This variant explained the evidence for linkage in this region when included as a covariate in the linkage analysis (change in LOD from 1.87 to 0.16), indicating that ITGB3 may be an important serotonin QTL.

Founder populations have been the subjects of complex disease studies because of their decreased genetic heterogeneity, increased linkage disequilibrium and more homogeneous environmental exposures. However, it is possible that disease alleles identified in founder populations may not contribute significantly to susceptibility in outbred populations. In this study we examine the Hutterites, a founder population of European descent, for 103 polymorphisms in 66 genes that are candidates for cardiovascular or inflammatory diseases. We compare the frequencies of alleles at these loci in the Hutterites to their frequencies in outbred European-American populations and test for associations with cardiovascular disease-associated phenotypes in the Hutterites. We show that alleles at these loci are found at similar frequencies in the Hutterites and in outbred populations. In addition, we report associations between 39 alleles or haplotypes and cardiovascular disease phenotypes (P<0.05), with five loci remaining significant after adjusting for multiple comparisons. These data indicate that this founder population is informative and offers considerable advantages for genetic studies of common complex diseases.

Background: Asthma is a chronic respiratory disease that often originates in early childhood. Although candidate gene studies have identified many potential asthma susceptibility genes in adult populations, few have studied associations with immune phenotypes in the first year that might be early clinical markers of asthma., Objective: The aim of this study was to assess the contribution of genetic variation to cytokine response profiles and atopic phenotypes in the first year of life in the Childhood Origin of Asthma cohort., Methods: Two hundred seven European American children participating in the Childhood Origin of Asthma study were genotyped for 61 single nucleotide polymorphisms in 35 genes involved in immune regulation. We examined the relationship between these single nucleotide polymorphisms and PHA-induced cytokine (IL-5, IL-10, IL-13, and IFN-gamma) response profiles at birth and at year 1, respiratory syncytial virus-induced wheezing and atopic dermatitis in the first year of life, and total IgE levels, peripheral blood eosinophil counts, and allergic sensitization at age 1 year. The data were analyzed by using censored regression for quantitative measurements and logistic regression for qualitative phenotypes., Results: The 237Gly allele of the high-affinity IgE receptor beta chain (FCER1B) and a silent substitution in the nitric oxide synthase (NOS)2A gene were associated with reduced IL-13 responses in cord blood (P = .0025 and P = .0062, respectively). A significant gene-gene interaction between FCER1B 237Gly and NOS2A D346D was detected, with individuals carrying the minor allele for both polymorphisms having the lowest cord blood IL-13 levels. Furthermore, the IL13 110Gln allele showed an association with increased IgE levels at year 1 (P = .0026), and the colony-stimulating factor 2 (CSF2) 117Thr allele showed an association with a greater increase in IL-5 responses during the first year (P = .0092). The TGF-beta1 (TGFB1) -509T allele was associated with respiratory syncytial virus-related wheezing in the first year (P = .0005). None of the polymorphisms included in this study were associated with atopic dermatitis during the first year or a positive RAST result at 1 year of age., Conclusion: These data suggest that variations in genes involved in immune regulation are associated with biologic and clinical phenotypes in the first year of life that might increase the risk for the subsequent development of childhood asthma.

Serum triglyceride (TG) level is a well-known risk factor for cardiovascular disease, a leading cause of morbidity and mortality in Western countries. Although genome-wide scans for TG have been conducted in several populations, few loci have shown strong evidence for linkage. The Hutterites are a founder population, which practices a communal lifestyle that includes a uniformly high-fat, high-cholesterol diet. We measured serum TG in 485 Hutterites >or=14 years old and performed a genome-wide scan to find genetic determinants of the observed variation in TG levels, using mapping methods that take advantage of the extensive inbreeding and linkage disequilibrium (LD) in this single, 1623-member pedigree. We report two highly significant associations with TG levels, alleles at D2S410 on 2q14 (locus P=5.8 x 10(-6), genome-wide P=0.005) and at IFNA on chromosome 9p21 (locus P=4.3 x 10(-5), genome-wide P=0.024). In each case, homozygosity at the locus is associated with low TG levels, suggesting that alleles at nearby loci may protect against high TG levels.

Kinetic 1D simulations reveal that a weak density depression in a current-carrying plasma can lead to the formation of a strong potential ramp (double layer). The ramp and plasma turbulence it creates share many features with recent particle and field measurements in the auroral ionosphere. An electron beam accelerated by the ramp produces a series of propagating electron phase-space holes via a spatial two-stream instability. Electron heating associated with the formation and merging of these holes is found to influence the subsequent evolution of the potential ramp.

We report direct measurements of parallel electric fields related to particle acceleration in a collisionless space plasma. The electric field is that of a monotonic potential ramp localized to approximately 10 debye lengths along the magnetic field. Electrons accelerated by the parallel electric field are accompanied by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes.

Two-dimensional simulations of beam-driven turbulence in the auroral ionosphere have shown the formation and instability of phase-space tubes. These tubes are a generalization of electron phase-space holes in a one-dimensional plasma. In a strongly magnetized plasma, such tubes vibrate at frequencies below the bounce frequency of the trapping potential. A theory for these vibrations yields quantitative agreement with kinetic simulations. Furthermore, the theory predicts that the vibrations can become unstable when resonantly coupled to electrostatic whistlers-also in agreement with simulations.