9,448 research outputs found
Hydrogen sensing performance of silica microfiber elaborated with Pd nanoparticles
A hydrogen sensor has been proposed by coating Pd nanoparticles-PMMA composite organic sol on silica microfiber independent on any expensive or complex chemical process. The thickness of cladding layer and the diameter of elaborated microfiber were determined as ∼20 μm and ∼57.93 μm, respectively. Due to the evanescent wave excited by silica microfiber and the amorphous structure of PMMA film, the Pd nanoparticles effectively absorbed the hydrogen molecules and resulted in the shift of resonance wavelength. The experimental results match well with an exponential curve with an average sensitivity of 5.58 nm/%, which is comparable to other electrochemical hydrogen sensors reported recently.The authors thank the support from the National Natural
Science Foundation of China (NSFC) under Grants (61405032,
61403074, 61605031); and Doctoral Scientific Research Startup Foundation of Liaoning Province under Grant (201501144); and Fundamental Research Funds for the Central Universities under Grants (N150404022, N150401001); and China Scholarship Council (201606085023)
Synapse: Interactive Guidance by Demonstration with Trial-and-Error Support for Older Adults to Use Smartphone Apps
As smartphones are widely adopted, mobile applications (apps) are emerging to
provide critical services such as food delivery and telemedicine. While bring
convenience to everyday life, this trend may create barriers for older adults
who tend to be less tech-savvy than young people. In-person or screen sharing
support is helpful but limited by the help-givers' availability. Video
tutorials can be useful but require users to switch contexts between watching
the tutorial and performing the corresponding actions in the app, which is
cumbersome to do on a mobile phone. Although interactive tutorials have been
shown to be promising, none was designed for older adults. Furthermore, the
trial-and-error approach has been shown to be beneficial for older adults, but
they often lack support to use the approach. Inspired by both interactive
tutorials and trial-and-error approach, we designed an app-independent mobile
service, \textit{Synapse}, for help-givers to create a multimodal interactive
tutorial on a smartphone and for help-receivers (e.g., older adults) to receive
interactive guidance with trial-and-error support when they work on the same
task. We conducted a user study with 18 older adults who were 60 and over. Our
quantitative and qualitative results show that Synapse provided better support
than the traditional video approach and enabled participants to feel more
confident and motivated. Lastly, we present further design considerations to
better support older adults with trial-and-error on smartphones
DisLoc: A Convex Partitioning Based Approach for Distributed 3-D Localization in Wireless Sensor Networks
Accurate localization in wireless sensor networks (WSNs) is fundamental to many applications, such as geographic routing and position-aware data processing. This, however, is challenging in large scale 3-D WSNs due to the irregular topology, such as holes in the path, of the network. The irregular topology may cause overestimated Euclidean distance between nodes as the communication path is bent and accordingly introduces severe errors in 3-D WSN localization. As an effort towards the issue, this paper develops a distributed algorithm to achieve accurate 3-D WSN localization. Our proposal is composed of two steps, segmentation and joint localization. In specific, the entire network is first divided into several subnetworks by applying the approximate convex partitioning. A spatial convex node recognition mechanism is developed to assist the network segmentation, which relies on the connectivity information only. After that, each subnetwork is accurately localized by using the multidimensional scaling-based algorithm. The proposed localization algorithm also applies a new 3-D coordinate transformation algorithm, which helps reduce the errors introduced by coordinate integration between subnetworks and improve the localization accuracy. Using extensive simulations, we show that our proposal can effectively segment a complex 3-D sensor network and significantly improve the localization rate in comparison with existing solutions
Di-μ-benzoato-κ3 O,O′:O;κ3 O:O,O′-bis[(benzoato-κ2 O,O′)(1,10-phenanthroline-κ2 N,N′)lead(II)]
In the centrosymmetric dinuclear title compound, [Pb2(C7H5O2)4(C12H8N2)2], two Pb2+ ions are connected by two tridentate bridging benzoate anions. The Pb2+ ion is seven-coordinated by five O atoms from three benzoate anions and two N atoms from the 1,10-phenanthroline ligands. The benzoate anions adopt two different coordination modes, one bidentate–chelating and one tridentate bridging–chelating. The three-dimensional supramolecular framework is achieved by intermolecular π–π stacking interactions, with a shortest centroid–centroid distance of 3.617 (4) Å
Fusformer: A Transformer-based Fusion Approach for Hyperspectral Image Super-resolution
Hyperspectral image has become increasingly crucial due to its abundant
spectral information. However, It has poor spatial resolution with the
limitation of the current imaging mechanism. Nowadays, many convolutional
neural networks have been proposed for the hyperspectral image super-resolution
problem. However, convolutional neural network (CNN) based methods only
consider the local information instead of the global one with the limited
kernel size of receptive field in the convolution operation. In this paper, we
design a network based on the transformer for fusing the low-resolution
hyperspectral images and high-resolution multispectral images to obtain the
high-resolution hyperspectral images. Thanks to the representing ability of the
transformer, our approach is able to explore the intrinsic relationships of
features globally. Furthermore, considering the LR-HSIs hold the main spectral
structure, the network focuses on the spatial detail estimation releasing from
the burden of reconstructing the whole data. It reduces the mapping space of
the proposed network, which enhances the final performance. Various experiments
and quality indexes show our approach's superiority compared with other
state-of-the-art methods
Effect of intense pulsed-light therapy on hair regrowth in C57BL/6J mice mediated by WNT/β-catenin signaling pathway
Purpose: To evaluate the effect of low-fluence intense pulsed light (IPL) on hair growth in C57BL/6 mice, and to explore the potential molecular mechanisms of IPL actions on hair growth.Methods: After low-fluence IPL irradiation was applied to depilated dorsal skin of C57BL/6 mice in the telogen, or resting hair cycle phase, tissue samples were obtained and used for histopathological analysis. Hair growth was analyzed by measuring hair length. In addition, protein expression levels of WNT3A and β-catenin were assayed by western blot.Results: Low-fluence IPL irradiation promoted hair growth by inducing the anagen, or growth, phase in telogenic C57BL/6J mice. In particular, hair growth analysis suggested that application of low-fluence IPL induced an earlier transition from telogen to anagen phase and prolonged the duration of anagen phase compared to the control group (p < 0.05). Moreover, western blotting assay revealed that WNT3A and β-catenin protein levels were up-regulated compared to the control group (p < 0.05).Conclusion: These findings suggest that low-fluence IPL irradiation may be effective for promoting hair regrowth via activation of the WNT/β-catenin pathway, and may, therefore, be a potential novel therapeutic treatment to stimulate hair regrowth.Keywords: Intense pulsed light, Hair follicles, Hair growth, WNT3a/β-catenin pathwa
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