Location and function of the slow afterhyperpolarization channels in the basolateral amygdala

The basolateral amygdala (BLA) assigns emotional significance to sensory stimuli. This association results in a change in the output (action potentials) of BLA projection neurons in response to the stimulus. Neuronal output is controlled by the intrinsic excitability of the neuron. A major determinant of intrinsic excitability in these neurons is the slow after hyperpolarization (sAHP) that follows action potential (AP) trains and produces spike-frequency adaptation. The sAHP is mediated by a slow calcium-activated potassium current (sI(AHP)), but little is known about the channels that underlie this current. Here, using whole-cell patch-clamp recordings and high-speed calcium imaging from rat BLA projection neurons, we examined the location and function of these channels. We determined the location of the sI(AHP) by applying a hyperpolarizing voltage step during the sI(AHP) and measuring the time needed for the current to adapt to the new command potential, a function of its electrotonic distance from the somatic recording electrode. Channel location was also probed by focally uncaging calcium using a UV laser. Both methodologies indicated that, in BLA neurons, the sI(AHP) is primarily located in the dendritic tree. EPSPs recorded at the soma were smaller, decayed faster, and showed less summation during the sAHP. Adrenergic stimulation and buffering calcium reduced the sAHP and the attenuation of the EPSP during the sAHP. The sAHP also modulated the AP in the dendrite, reducing the calcium response evoked by a single AP. Thus, in addition to mediating spike-frequency adaptation, the sI(AHP) modulates communication between the soma and the dendrite

Together | Apart: Printmaking and the Space Between

In this practice-led creative research, being both artist and identical twin, I examine sameness and difference in the relationships between two people and between multiple objects/creative works. Through the inherent ability of printmaking processes to produce multiples and the attendant installation opportunities created by punctuated space, I unfold and re-tell a doubled and ambiguous understanding of being in the world. Martin Heidegger’s notion of Being-in-the-world (Dasein) underpins and situates my understanding of being in the world, thrown into a world as an individual, and my existence as a double: being in the world with others. I relate his thinking through Barbara Bolt’s interpretation of Heidegger’s Dasein to the artist’s making to seek new ways of understanding Dasein / being-there. The work I make is a metaphor for investigating how I understand the world around me. To do this, I discuss tacit methodology and draw together the ‘what’, ‘how’ and ‘why’, which forms and informs a praxical knowledge, a knowledge that comes from doing and its reflective dimension. By investigating practices by both historical and contemporary artists who employ the diptych as a device to present works as an interconnected pair, I position my forms of the diptych to create relationships of closeness and separation, together | apart. The space in between two people or artworks—a gap—becomes instrumental in separating while simultaneously relating to and evoking continuation and connection. Imagery derived from and alluding to the body, in a gap between figuration and abstraction, is developed in an iterative, open-ended series of prints. Academic discussions about the nature of studio research are applied and interpreted through creative practice, imparting and enabling both an informed, personally situated perspective and an appraisal of the engagement of other artists, such as Roni Horn, Lesley Duxbury, and Paul Uhlmann, whose practices of ambiguity, in-between spaces and gaps are embedded in the wider field of visual arts practices. This research contributes to a broader field of discussion of understandings of being in the world, of spaces in-between and impermanence as related to unique printmaking practices

A review of the microbiome associated with human decomposition

The decomposition of human remains involves a complex microbial ecology that few studies have examined in depth. This review investigated the microbiome of human decomposition to further understand their functions within the decomposition process and their potential to increase the accuracy of post-mortem interval (PMI) estimations in forensic applications. The aims of the literature review were to (1) identify the external microbiome responsible for human decomposition, focusing on insect, soil and skin sources, (2) determine the roles of external bacteria in the various stages of human decomposition and (3) to analyse and compare the current contributions of literature in furthering the understanding of the ecological mosaic of decomposition. The current literature was reviewed and their contributions to necrobiome research was analysed using qualitative and contemporary research techniques. Bacteria were found to play a significant role in each stage of human decomposition with multiple studies demonstrating an observable successive shift in microbial communities through time. This change in community profile was found to be an important biomarker for the estimation of the PMI and potential substitute for entomological techniques currently utilised in forensic investigations. High interpersonal variation between decomposition events, in addition to narrow geographic specificity, represented limitations in the studies which may be remedied by increasing sample size while focusing on different geographic regions and environmental conditions

Cross-partitions for Identifying Appropriate Multivariate Statistics

By determining whether independent or dependent variables, or both, are multivariate and specifying the scale of measurement of the variables an appropriate multivariate statistical procedure can be identified. Reference are given for locating additional information on these procedures. For many years Tatsuoka and Tiedeman\u27s (1963) cross partition in Gages\u27 Handbook of Research in Teaching has been a useful tool for identifying an appropriate statistic for a particular research question. Since its publication many new statistical procedures have been developed, particularly for use with multivariate designs. The purpose of this article is to incorporate the new procedures and those in Tatsuoka and Tiedeman in a new set of cross partitions focusing only on multivariate cases. A study is multivariate if there is more than one independent variable and/or more than one dependent variable. Some of the techniques used with multivariate statistics such as multiple regression are well known. Other multivariate techniques are available for other combinations of variables, some of which are not so familiar. Table I lists statistical procedures appropriate when the independent variable is multivariate and the dependent variable is univariate. When the dependent variable is multivariate and the independent variable is univariate, Table II is appropriate. Finally, where both the independent and dependent variables are multivariate Table Ill should be consulted. (Factor analysis, a commonly used multivariate statistical procedure, is not included in any of these table, since it is used when the variables are not classified as independent or dependent.) After locating the proper table one must identify the scale of measurement of the variables (Stevens, 1946)

Exploring the effect of context and expertise on attention : is attention shifted by information in medical images?

Radiologists make critical decisions based on searching and interpreting medical images. The probability of a lung nodule differs across anatomical regions within the chest, raising the possibility that radiologists might have a prior expectation that creates an attentional bias. The development of expertise is also thought to cause "tuning" to relevant features, allowing radiologists to become faster and more accurate at detecting potential masses within their domain of expertise. Here, we tested both radiologists and control participants with a novel attentional-cueing paradigm to investigate whether the deployment of attention was affected (1) by a context that might invoke prior knowledge for experts, (2) by a nodule localized either on the same or on opposite sides as a subsequent target, and (3) by inversion of the nodule-present chest radiographs, to assess the orientation specificity of any effects. The participants also performed a nodule detection task to verify that our presentation duration was sufficient to extract diagnostic information. We saw no evidence of priors triggered by a normal chest radiograph cue affecting attention. When the cue was an upright abnormal chest radiograph, radiologists were faster when the lateralised nodule and the subsequent target appeared at the same rather than at opposite locations, suggesting attention was captured by the nodule. The opposite pattern was present for inverted images. We saw no evidence of cueing for control participants in any condition, which suggests that radiologists are indeed more sensitive to visual features that are not perceived as salient by naïve observers

The effect of various periods of mental practice on the learning of a novel gross motor task

This experiment was conducted to determine the effect of various periods of mental practice time on the performance of a novel gross motor task. Fifty-six college women who were enrolled at Los Angeles Pierce College volunteered as subjects for this experiment. The subjects were selected as a result of their unfamiliarity with the task. Groups A, B, C, and D were randomly assigned from four similar activity classes. Group A mentally practiced the task for three minutes; Group B for six minutes; Group C for nine minutes; and Group D did not practice. The experiment lasted five weeks with training sessions twice a week. The first week was devoted to the pre-test; the last week to the post-test. The analysis of variance and covariance tests were used to treat the data. The data revealed significant differences between the three-minute mental practice group and the control group, but none of the three practice groups differed from each other. The results justified the null hypothesis that there is no significant difference in the degree of performance of a headstand for subjects who mentally practice for various periods of time.Includes bibliographical references (pages 43-45)California State University, Northridge. Department of Kinesiology

That Thing in Your Pocket: Cultivating a Geo-Sustainable Mindset in High School Chemistry Students Using GIS to Study Smartphone Components

Smartphones are ubiquitous in high schools across the US, but students rarely learn about the complex world of elements and materials beneath their shiny exteriors. Educators can bridge the gap between the abstract concept of smartphone elements and the real-world geography of their origin and impact by integrating ArcGIS geospatial software into their curriculum. A team of researchers has been working with high school teachers to infuse geospatial concepts and technologies into their teaching. One project involved a teacher using GIS to revisit his approach to teaching the periodic table: he would have his students investigate the global origins of smartphone components. This approach equipped students with essential knowledge about the materials that power their daily lives and nurtured critical thinking skills and an awareness of the environmental and ethical dimensions of technology consumption. This paper includes a description of the project and how geospatial technology was utilized, as well as a discussion on the implications and future research in this area