Revving it Up! Helping Students Investigate the Forces that Power a Motor

The Electric Motors learning cycle demonstrates how magnetic fields and electric currents interact to produce a force on a moving charge. In the exploratory activity students manipulate a magnetic field to produce motion in a cone and construct an electric motor by winding an armature and field coils. In the concept development activity, students construct a simple motor with a single coil and ceramic magnets. They feel the force on a current carrying coil in a magnetic field that leads to the right-hand rule. They also analyze the operation of a motor used to power a toy car. The application activity compares the mechanical power transferred in lifting weights with an electric motor to the power consumed by the electric motor. This article promotes National Science Education Content Standards A and B, and Iowa Teaching Standards 2, 3, 4, and 5

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Etnobotánica de las palmeras Copernicia alba Morong y Trithrinax schizophylla Drude en el Gran Chaco y alrededores: una revisión

Se presenta una revisión exhaustiva sobre la etnobotánica de Copernicia alba y Trithrinax schizophylla, palmeras típicas del Chaco húmedo y semiárido argentino, paraguayo y boliviano, que son especies multipropósito de gran importancia simbólica y utilitaria para las diversas culturas que habitan la región. Sobre la base de datos primarios y secundarios se compilan sus usos, pormenores del manejo actual y pasado, y aspectos sobre su importancia simbólica y en el ecosistema, con el fin de mostrar su papel para los distintos pueblos del Chaco, contribuir a revalorizar a estas especies, exponer usos que pueden estar invisibilizados y aportar con ello a su conocimiento y conservación. Se discuten los datos con énfasis en las formas de manejo local, los factores socioambientales asociadas y el potencial de estas especies como elementos que sirvan a proyectos de uso sustentable y conservación mediante el uso. Se resalta la necesidad de desarrollar investigaciones sobre aspectos vinculados a su uso (formas y tasas de extracción,posibilidad de cultivo, entre otros) y su etnobotánica, y se remarca la importancia de considerar las pautas y creencias culturales locales a la hora de trabajar y proponer acciones relacionadas al uso y manejo de estas especies.Fil: Suarez, Maria Eugenia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Callao Escalada, Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Herrera Cano, Anahí Naymé. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Marino, Gustavo D.. Aves Argentinas. Bosque Atlántico y Gran Chaco. Programa NEA; Argentina. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias; Argentin

Value Creation in a Pedagogically-Focused Faculty Online Learning Community

Faculty online learning communities (FOLCs) can help faculty effectively adopt and persist in using research-based curricula. This paper documents faculty perspectives on the value they gained from participating in a multi-year FOLC designed to help them implement an inquiry-based physical science curriculum. Personal value narratives were collected from 11 volunteer FOLC participants. In the narratives, participants responded to prompts regarding their initial reasons for participation, activities they engaged in, and values they gained, as well as how participation impacted their profession, social connections, professional practice, and ability to influence their world as teachers. Qualitative analysis shows that the values faculty gained through their participation in the FOLC could be associated with four major areas of impact: teaching, community, leadership and personal development. The first two aligned with the initial goals of the FOLC, while the latter two emerged organically through participation over its four-year duration. The methods used to assess value creation in the NGPET FOLC and the findings from this study can inform other professionals who aspire to create and sustain a long-standing faculty development community and understand its impacts

Dynamic constriction and fission of endoplasmic reticulum membranes by reticulon

The endoplasmic reticulum (ER) is a continuous cell-wide membrane network. Network formation has been associated with proteins producing membrane curvature and fusion, such as reticulons and atlastin. Regulated network fragmentation, occurring in different physiological contexts, is less understood. Here we find that the ER has an embedded fragmentation mechanism based upon the ability of reticulon to produce fission of elongating network branches. In Drosophila, Rtnl1-facilitated fission is counterbalanced by atlastin-driven fusion, with the prevalence of Rtnl1 leading to ER fragmentation. Ectopic expression of Drosophila reticulon in COS-7 cells reveals individual fission events in dynamic ER tubules. Consistently, in vitro analyses show that reticulon produces velocity-dependent constriction of lipid nanotubes leading to stochastic fission via a hemifission mechanism. Fission occurs at elongation rates and pulling force ranges intrinsic to the ER, thus suggesting a principle whereby the dynamic balance between fusion and fission controlling organelle morphology depends on membrane motility

TIGER : The gene expression regulatory variation landscape of human pancreatic islets

Genome-wide association studies (GWASs) identified hundreds of signals associated with type 2 diabetes (T2D). To gain insight into their underlying molecular mechanisms, we have created the translational human pancreatic islet genotype tissue-expression resource (TIGER), aggregating >500 human islet genomic datasets from five cohorts in the Horizon 2020 consortium T2DSystems. We impute genotypes using four reference panels and meta-analyze cohorts to improve the coverage of expression quantitative trait loci (eQTL) and develop a method to combine allele-specific expression across samples (cASE). We identify >1 million islet eQTLs, 53 of which colocalize with T2D signals. Among them, a low-frequency allele that reduces T2D risk by half increases CCND2 expression. We identify eight cASE colocalizations, among which we found a T2D-associated SLC30A8 variant. We make all data available through the TIGER portal (http://tiger.bsc.es), which represents a comprehensive human islet genomic data resource to elucidate how genetic variation affects islet function and translates into therapeutic insight and precision medicine for T2D.Peer reviewe

Blend design tools for Medium Combustion Plants (MCP) firing biomass wastes

Accepted manuscriptA feasible alternative for agricultural or forestry waste management is the operation of a distributed network of sustainable Medium Combustion Plants (MCPs). However, one of the main factors that hinder its development is the propensity to operational problems derived from corrosion, slagging and fouling characteristics of both bottom and fly ashes. Therefore, a cost-effective approach for these multi-product MCP could be based on predictive tools for an optimal formulation of a fuel blend. This work focuses on the assessment of the ability of these methods to provide guidance for preventing ash-related operational problems and to provide fuel-blending rules. The more widespread tools pertain to two types: compositional classification based on chemical analysis of laboratory ashes, and thermodynamic prediction of the most likely species and phases. Both criterion numbers and compositional maps are ranking methods based on the chemical analysis at a given ashing temperature. Thermodynamic equilibrium modeling is not constrained by any difference in the physical conditions of the MCP compared to those in the laboratory. Both kind of prediction tools have been validated in an MCP firing olive tree pruning residues as well as its typical blends in order to mimic a plausible pattern of fuels along a full year operating campaign. An intensive experimental campaign encompasses plant monitoring and off-line analysis of the ashes along the process line. Interpretation of compositional plots has revealed to be potentially sensitive to ashing temperature. Here are presented examples showing how this variable could lead to either insignificant differences or to a substantial disparity in the a priori fuel diagnosis. Some inconsistencies have been observed between the predictions based on criterion numbers, even for the same fuel and for ranking rules specifically formulated for biomasses. Moreover, it does not match consistently with the information obtained from phase diagrams. Therefore, their use should be limited to the case of a well-established selection of a fuel index for a well-defined fuel provided empirical evidence of an enough good description of the ash behavior, which is not the most frequent case. Thermodynamic equilibrium calculations allow a more precise prediction of the main species in the condensed phase, without the constraint of the ashing temperature. Elemental closure of main ashforming elements with the chemical analysis of the process ashes presents small differences, and their proximity localization on the phase diagrams denote similar prediction between predicted and process ashes

Biomechanical analysis and modeling of different vertebral growth patterns in adolescent idiopathic scoliosis and healthy subjects

<p>Abstract</p> <p>Background</p> <p>The etiology of AIS remains unclear, thus various hypotheses concerning its pathomechanism have been proposed. To date, biomechanical modeling has not been used to thoroughly study the influence of the abnormal growth profile (i.e., the growth rate of the vertebral body during the growth period) on the pathomechanism of curve progression in AIS. This study investigated the hypothesis that AIS progression is associated with the abnormal growth profiles of the anterior column of the spine.</p> <p>Methods</p> <p>A finite element model of the spinal column including growth dynamics was utilized. The initial geometric models were constructed from the bi-planar radiographs of a normal subject. Based on this model, five other geometric models were generated to emulate different coronal and sagittal curves. The detailed modeling integrated vertebral body growth plates and growth modulation spinal biomechanics. Ten years of spinal growth was simulated using AIS and normal growth profiles. Sequential measures of spinal alignments were compared.</p> <p>Results</p> <p>(1) Given the initial lateral deformity, the AIS growth profile induced a significant Cobb angle increase, which was roughly between three to five times larger compared to measures utilizing a normal growth profile. (2) Lateral deformities were absent in the models containing no initial coronal curvature. (3) The presence of a smaller kyphosis did not produce an increase lateral deformity on its own. (4) Significant reduction of the kyphosis was found in simulation results of AIS but not when using the growth profile of normal subjects.</p> <p>Conclusion</p> <p>Results from this analysis suggest that accelerated growth profiles may encourage supplementary scoliotic progression and, thus, may pose as a progressive risk factor.</p

Influence of Ecto-Nucleoside Triphosphate Diphosphohydrolase Activity on Trypanosoma cruzi Infectivity and Virulence

The protozoan Trypanosoma cruzi is the causative agent of Chagas disease, an endemic zoonosis present in some countries of South and Central Americas. The World Health Organization estimates that 100 million people are at risk of acquiring this disease. The infection affects mainly muscle tissues in the heart and digestive tract. There are no vaccines or effective treatment, especially in the chronic phase when most patients are diagnosed, which makes a strong case for the development of new drugs to treat the disease. In this work we evaluate a family of proteins called Ecto-Nucleoside-Triphosphate-Diphosphohydrolase (Ecto-NTPDase) as new chemotherapy target to block T. cruzi infection in mammalian cells and in mice. We have used inhibitors and antibodies against this protein and demonstrated that T. cruzi Ecto-NTPDases act as facilitators of infection in mammalian cells and virulence factors in mice model. Two of the drugs used in this study (Suramin and Gadolinium) are currently used for other diseases in humans, supporting the possibility of their use in the treatment of Chagas disease