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  1. Abstract

    Leucine-rich repeat containing 10 (LRRC10) is a cardiomyocyte-specific protein, but its role in cardiac biology is little understood. Recently Lrrc10 was identified as required for endogenous cardiac regeneration in zebrafish; however, whether LRRC10 plays a role in mammalian heart regeneration remains unclear. In this study, we demonstrate thatLrrc10–/–knockout mice exhibit a loss of the neonatal mouse regenerative response, marked by reduced cardiomyocyte cytokinesis and increased cardiomyocyte binucleation. Interestingly, LRRC10 deletion disrupts the regenerative transcriptional landscape of the regenerating neonatal mouse heart. Remarkably, cardiac overexpression of LRRC10 restores cardiomyocyte cytokinesis, increases cardiomyocyte mononucleation, and the cardiac regenerative capacity ofLrrc10–/–mice. Our results are consistent with a model in which LRRC10 is required for cardiomyocyte cytokinesis as well as regulation of the transcriptional landscape during mammalian heart regeneration.

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  2. Simultaneous measurements of two nitrogen vacancy centers in diamond enables spatiotemporal magnetometry. 
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    Free, publicly-accessible full text available December 23, 2023
  3. Flying social insects can provide model systems for in-flight interactions in computationally-constrained aerial robot swarms. The social interactions in flying insects may be chemically modulated and quantified via recent measurement advancements able to simultaneously make precise measurements of insect wing and body motions. This paper presents the first in-flight quantitative measurements of ethanol-exposed honey bee body and wing kinematics in archival literature. Four high-speed cameras (9000 frames/sec) were used to record the wing and body motions of flying insects (Apis mellifera) and automated analysis was used to extract 9000 frame/sec measurements of honey bees’ wing and body motions through data association, hull reconstruction, and segmentation. The kinematic changes induced by exposure to incremental ethanol concentrations from 0% to 5% were studied using statistical analysis tools. Analysis considered trial-wise mean and maximum values and gross wingstroke parameters, and tested deviations for statistical significance using Welch’s t-test and Cohen’s d test. The results indicate a decrease in maximal heading and pitch rates of the body, and that roll rate is affected at high concentrations (5%). The wingstroke effects include a stroke frequency decrease and stroke amplitude increase for 2.5% or greater concentrations, gradual stroke inclination angle increase up to 2.5% concentration, and a more planar wingstroke with increasing concentration according to bulk wingstroke analysis. These ethanol-exposure effects provide a basis to separate ethanol exposure and neighbor effects in chemically mediated interaction studies. 
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  4. null (Ed.)
    An intelligent system can provide sufficient collaborative opportunities and support yet fail to be pedagogically effective if the students are unwilling to participate. One of the common ways to assess motivation is using self-report questionnaires, which often do not take the context and the dynamic aspect of motivation into account. To address this, we propose personas, a user-centered design approach. We describe two design iterations where we: identify motivational factors related to students’ collaborative behaviors; and develop a set of representative personas. These personas could be embedded in an interface and be used as an alternative method to assess motivation within ITS. 
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  5. Computer-Supported Collaborative Learning (CSCL) environments are often designed to support collaboration within a single digital platform. However, with the growth of technology in classrooms, students often find themselves working in multiple contexts (i.e., a student might work face-to-face with a peer on one task and then move to engaging in an online discussion for homework). We have created a CSCL environment that aims to support student help-giving across a variety of digital platforms. This paper describes three cycles of a design-based research study that aims to design a system to support help-giving and improve interaction quantity and quality across different contexts as well as to better understand whether students benefit by the addition of multiple contexts. The paper shares major refinements across the three cycles that worked to balance research, pedagogical, and technological goals to improve students’ help-giving behavior in a middle-school mathematics classroom. 
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  6. A low-energy hardware implementation of deep belief network (DBN) architecture is developed using near-zero energy barrier probabilistic spin logic devices (p-bits), which are modeled to real- ize an intrinsic sigmoidal activation function. A CMOS/spin based weighted array structure is designed to implement a restricted Boltzmann machine (RBM). Device-level simulations based on precise physics relations are used to validate the sigmoidal relation between the output probability of a p-bit and its input currents. Characteristics of the resistive networks and p-bits are modeled in SPICE to perform a circuit-level simulation investigating the performance, area, and power consumption tradeoffs of the weighted array. In the application-level simulation, a DBN is implemented in MATLAB for digit recognition using the extracted device and circuit behavioral models. The MNIST data set is used to assess the accuracy of the DBN using 5,000 training images for five distinct network topologies. The results indicate that a baseline error rate of 36.8% for a 784x10 DBN trained by 100 samples can be reduced to only 3.7% using a 784x800x800x10 DBN trained by 5,000 input samples. Finally, Power dissipation and accuracy tradeoffs for probabilistic computing mechanisms using resistive devices are identified. 
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  7. Abstract

    Selectfluor, [1‐chloromethyl‐4‐fluoro‐1,4‐diazoniabicyclo‐[2.2.2]octane bis(tetrafluoroborate)], is not only an important electrophilic fluorinating agent but also a facile and efficient “fluorine‐free” functional reagent in other organic reactions. In this Minireview, we will present a brief history of Selectfluor as a transition metal oxidant, fluorine cation and radical initiator in “fluorine‐free” functionalizations over the last five years.

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