559 research outputs found
‘Why Do We Think We Are Doing Everything Right [Just] Because We Do It’: What Transforms Chinese and Scottish Student-teachers’ Taken-for-granted Views in Study Abroad Experiences
This paper reports on how varied study abroad experiences transformed understanding of difference of student-teachers from two universities. Data were collected through a qualitative questionnaire and semi-structured interviews with 14 Chinese and Scottish student-teachers who presented what they had experienced and how they had made sense of difference. Drawing on transformative learning, this study reveals that opportunities to experience difference and resultant emotional struggles can develop student-teachers’ emotional maturity and readiness for change. It also highlights that critical reflection on challenges in their preconceptions about the self and others is essential to transform their preconceived views and develop their openness to difference. To maximise the transformative potential of study abroad programmes, we argue that student-teachers must be provided with a discourse that disrupts their taken-for-granted views and learning opportunities that have a critical orientation
FoveaBox: Beyond Anchor-based Object Detector
We present FoveaBox, an accurate, flexible, and completely anchor-free
framework for object detection. While almost all state-of-the-art object
detectors utilize predefined anchors to enumerate possible locations, scales
and aspect ratios for the search of the objects, their performance and
generalization ability are also limited to the design of anchors. Instead,
FoveaBox directly learns the object existing possibility and the bounding box
coordinates without anchor reference. This is achieved by: (a) predicting
category-sensitive semantic maps for the object existing possibility, and (b)
producing category-agnostic bounding box for each position that potentially
contains an object. The scales of target boxes are naturally associated with
feature pyramid representations. In FoveaBox, an instance is assigned to
adjacent feature levels to make the model more accurate.We demonstrate its
effectiveness on standard benchmarks and report extensive experimental
analysis. Without bells and whistles, FoveaBox achieves state-of-the-art single
model performance on the standard COCO and Pascal VOC object detection
benchmark. More importantly, FoveaBox avoids all computation and
hyper-parameters related to anchor boxes, which are often sensitive to the
final detection performance. We believe the simple and effective approach will
serve as a solid baseline and help ease future research for object detection.
The code has been made publicly available at
https://github.com/taokong/FoveaBox .Comment: IEEE Transactions on Image Processing, code at:
https://github.com/taokong/FoveaBo
A Spatiotemporal-chaos-based Encryption Having Overall Properties Considerably Better Than Advanced Encryption Standard
Spatiotemporal chaos of a two-dimensional one-way coupled map lattice is used
for chaotic cryptography. The chaotic outputs of many space units are used for
encryption simultaneously. This system shows satisfactory cryptographic
properties of high security; fast encryption (decryption) speed; and robustness
against noise disturbances in communication channel. The overall features of
this spatiotemporal-chaos-based cryptosystem are better than chaotic
cryptosystems known so far, and also than currently used conventional
cryptosystems, such as the Advanced Encryption Standard (AES).Comment: 11 pages, 3 figure
Experimental observation of superscattering
Superscattering, induced by degenerate resonances, breaks the fundamental
single-channel limit of scattering cross section of subwavelength structures;
in principle, an arbitrarily large total cross section can be achieved via
superscattering. It thus provides a unique way to strengthen the light-matter
interaction at the subwavelength scale, and has many potential applications in
sensing, energy harvesting, bio-imaging (such as magnetic resonance imaging),
communication and optoelectronics. However, the experimental demonstration of
superscattering remains an open challenge due to its vulnerability to
structural imperfections and intrinsic material losses. Here we report the
first experimental evidence for superscattering, by demonstrating the
superscattering simultaneously in two different frequency regimes through both
the far-field and near-field measurements. The underlying mechanism for the
observed superscattering is the degenerate resonances of confined surface
waves, by utilizing a subwavelength metasurface-based multilayer structure. Our
work paves the way towards practical applications based on superscattering
Pulmonary alveolar type I cell population consists of two distinct subtypes that differ in cell fate.
Pulmonary alveolar type I (AT1) cells cover more than 95% of alveolar surface and are essential for the air-blood barrier function of lungs. AT1 cells have been shown to retain developmental plasticity during alveolar regeneration. However, the development and heterogeneity of AT1 cells remain largely unknown. Here, we conducted a single-cell RNA-seq analysis to characterize postnatal AT1 cell development and identified insulin-like growth factor-binding protein 2 (Igfbp2) as a genetic marker specifically expressed in postnatal AT1 cells. The portion of AT1 cells expressing Igfbp2 increases during alveologenesis and in post pneumonectomy (PNX) newly formed alveoli. We found that the adult AT1 cell population contains both Hopx+Igfbp2+ and Hopx+Igfbp2- AT1 cells, which have distinct cell fates during alveolar regeneration. Using an Igfbp2-CreER mouse model, we demonstrate that Hopx+Igfbp2+ AT1 cells represent terminally differentiated AT1 cells that are not able to transdifferentiate into AT2 cells during post-PNX alveolar regeneration. Our study provides tools and insights that will guide future investigations into the molecular and cellular mechanism or mechanisms underlying AT1 cell fate during lung development and regeneration
- …