Chloride channels in stellate cells are essential for uniquely high secretion rates in neuropeptide-stimulated Drosophila diuresis

Epithelia frequently segregate transport processes to specific cell types, presumably for improved efficiency and control. The molecular players underlying this functional specialization are of particular interest. In Drosophila, the renal (Malpighian) tubule displays the highest per-cell transport rates known and has two main secretory cell types, principal and stellate. Electrogenic cation transport is known to reside in the principal cells, whereas stellate cells control the anion conductance, but by an as-yet-undefined route. Here, we resolve this issue by showing that a plasma membrane chloride channel, encoded by ClC-a, is exclusively expressed in the stellate cell and is required for Drosophila kinin-mediated induction of diuresis and chloride shunt conductance, evidenced by chloride ion movement through the stellate cells, leading to depolarization of the transepithelial potential. By contrast, ClC-a knockdown had no impact on resting secretion levels. Knockdown of a second CLC gene showing highly abundant expression in adult Malpighian tubules, ClC-c, did not impact depolarization of transepithelial potential after kinin stimulation. Therefore, the diuretic action of kinin in Drosophila can be explained by an increase in ClC-a–mediated chloride conductance, over and above a resting fluid transport level that relies on other (ClC-a–independent) mechanisms or routes. This key segregation of cation and anion transport could explain the extraordinary fluid transport rates displayed by some epithelia

Dealing with non-termination in DCGs

The objective of this paper is to study a practical approach to deal with non-termination in de nite clause grammars. We focus on two problems, loop and cyclic structure detection and representation, maintaining a tight balance between practical e ciency and operational completeness. In order to guarantee the validity of our conclusions, we rst map our study to a common situated framework, where the e ectiveness of each approach will be examined and, later, compared by running experiments.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

Dealing with non-termination in DCGs

The objective of this paper is to study a practical approach to deal with non-termination in de nite clause grammars. We focus on two problems, loop and cyclic structure detection and representation, maintaining a tight balance between practical e ciency and operational completeness. In order to guarantee the validity of our conclusions, we rst map our study to a common situated framework, where the e ectiveness of each approach will be examined and, later, compared by running experiments.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

Stereoselective cyanation of 4-formyl and 4-imino-β-lactams: Application to the synthesis of polyfunctionalized γ-lactams

The stereoselective reaction of 4-oxoazetidine-2-carbaldehydes and their corresponding imines with cyanide-based reagents give β-lactam α-aminonitriles, which are chameleonic building blocks for the controlled synthesis of a variety of new compounds including functionalized γ-lactams, succinimide derivatives, and diamino-lactams derivatives in optically pure form. © 2012 Elsevier Ltd. All rights reserved.Peer Reviewe

Academic impact of sudden and unforeseen changes in the learning environment due to the COVID-19 pandemic

This version of the article has been accepted for publication, after peer review, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: https://doi.org/10.1504/IJIL.2022.126631[Abstract]: This study evaluates the impact of changes in the learning environment due to the COVID-19 restrictions at the university level in Singapore based on the grades and student evaluations of 282 students from two cohorts who in 2020 experienced in-class and online teaching consecutively and compares academic performance in both learning environments considering the existing relationship between student evaluations and teacher-student interaction. Results show differences in academic performance on the final exam between the two modes, however, these differences are not related to the student evaluation of the lecturer nor teacherstudent interaction as these remained unalterable despite the transition from in-class to online learning. The conclusion is that it is possible to maintain an optimum quality of education without alterations in student evaluations nor in teacher-student interaction in both online and inclass contexts. However, it is necessary to design a course appropriate assessment strategy consistent with the specific learning environmen

Performance assessment of existing models to predict brittle failure modes of steel-to-timber connections loaded parallel-to-grain with dowel-type fasteners

For safety reasons, ductile failure in timber connections with dowel-type fasteners is always recommended. It has usually been assumed that it can be achieved by fulfilling minimum spacing requirements between fasteners. However, recent works address the need to account for brittle failure modes (namely splitting, row-shear, and block and plug-shear) in connections loaded parallel-to-the-grain in an explicit manner, in order to evaluate them and achieve the desired ductility. This article describes the brittle failure modes and reviews the existing calculation models proposed by several authors – some of them included in standards. Finally, the performance of these models is assessed against an extensive database of tests gathered from the literature following a comprehensive methodology

Systematic Evaluation of Applying Space-Filling Curves to Automotive Maneuver Detection

Identifying driving maneuvers plays an essential role on-board vehicles to monitor driving and driver states, as well as off-board to train and evaluate machine learning algorithms for automated driving for example. Maneuvers can be characterized by vehicle kinematics or data from its surroundings including other traffic participants. Extracting relevant maneuvers therefore requires analyzing time-series of (i) structured, multi-dimensional kinematic data, and (ii) unstructured, large data samples for video, radar, or LiDAR sensors. However, such data analysis requires scalable and computationally efficient approaches, especially for non-annotated data. In this paper, we are presenting a maneuver detection approach based on two variants of space-filling curves (Z-order and Hilbert) to detect maneuvers when passing roundabouts that do not use GPS data. We systematically evaluate their respective performance by including permutations of selections of kinematic signals at varying frequencies and compare them with two alternative baselines: All manually identified roundabouts, and roundabouts that are marked by geofences. We find that encoding just longitudinal and lateral accelerations sampled at 10Hz using a Hilbert space-filling curve is already successfully identifying roundabout maneuvers, which allows to avoid the use of potentially sensitive signals such as GPS locations to comply with data protection and privacy regulations like GDPR.Comment: 7 pages, 4 figure

Promoting Entrepreneurship amid Youth in Windhoek’s Informal Settlements: A Namibian Case

Considering the high unemployment rate among Namibian youth and a lack of job opportunities, the promotion of entrepreneurship has gained wider attention in the country. A number of initiatives have been started such as entrepreneurship trainings and workshops, business idea competitions, etc. All these aim to inspire young people to think of alternative income sources. As part of a two-year funded community outreach research and development (R&D) project, we have investigated participatory approaches to engage marginalized youth into conceptualizing their own context, imparting skills, and deriving new career paths. This article reports and reflects on one of the interventions we have recently concluded with a group of youth in Havana, an informal settlement in the outskirts of Windhoek. We conducted what we entitled “The Havana Entrepreneur”, a series of interactions inspired upon the model of the American reality game show “The Apprentice”. Over a number of weeks two youth groups were given challenges to tackle by means of competing against one another. After completion of each challenge, groups were rated by a number of judges on skills demonstrated such as marketing, presentation, reflection and creativity among others. We observed an increase in, and improvement of skills revealed along tasks’ completion, besides an openly expressed self-realization and discovery of abilities by participants. Moreover, the youth are currently engaged in the continuation of activities beyond the initial entrepreneurial interactions. Thus we suggest replicating “The Havana Entrepreneur”, including the recording on camera of it by the youth themselves as a new mode to instigating a wider entrepreneurial spirit in informal settlements