165 research outputs found
High-capacity quantum secure direct communication based on quantum hyperdense coding with hyperentanglement
We present a quantum hyperdense coding protocol with hyperentanglement in
polarization and spatial-mode degrees of freedom of photons first and then give
the details for a quantum secure direct communication (QSDC) protocol based on
this quantum hyperdense coding protocol. This QSDC protocol has the advantage
of having a higher capacity than the quantum communication protocols with a
qubit system. Compared with the QSDC protocol based on superdense coding with
-dimensional systems, this QSDC protocol is more feasible as the preparation
of a high-dimension quantum system is more difficult than that of a two-level
quantum system at present.Comment: 5 pages, 2 figur
Wi-fi and radar fusion for head movement sensing through walls leveraging deep learning
The detection of head movement plays a crucial role in human–computer interaction systems. These systems depend on control signals to operate a range of assistive and augmented technologies, including wheelchairs for Quadriplegics, as well as virtual/augmented reality and assistive driving. Driver drowsiness detection and alert systems aided by head movement detection can prevent major accidents and save lives. Wearable devices, such as MagTrack consist of magnetic tags and magnetic eyeglasses clips and are intrusive. Vision-based systems suffer from ambient lighting, line of sight, and privacy issues. Contactless sensing has become an essential part of next-generation sensing and detection technologies. Wi-Fi and radar provide contactless sensing, however, in assistive driving they need to be inside enclosures or dashboards, which for all practical purposes in this article have been considered as through walls. In this study, we propose a contactless system to detect human head movement with and without walls. We used ultra-wideband (UWB) radar and Wi-Fi signals, leveraging machine and deep learning (DL) techniques. Our study analyzes the six common head gestures: right, left, up, and down movements. Time-frequency multiresolution analysis based on wavelet scalograms is used to obtain features from channel state information values, along with spectrograms from radar signals for head movement detection. Feature fusion of both radar and Wi-Fi signals is performed with state-of-the-art DL models. A high classification accuracy of 83.33% and 91.8% is achieved overall with the fusion of VGG16 and InceptionV3 model features trained on radar and Wi-Fi time–frequency maps with and without the walls, respectively
The Fat Mass and Obesity Associated Gene, FTO, Is Also Associated with Osteoporosis Phenotypes
Obesity and osteoporosis are closely correlated genetically. FTO gene has been consistently identified to be associated with obesity phenotypes. A recent study reported that the mice lacking Fto could result in lower bone mineral density (BMD). Thus, we hypothesize that the FTO gene might be also important for osteoporosis phenotypes. To test for such a hypothesis, we performed an association analyses to investigate the relationship between SNPs in FTO and BMD at both hip and spine. A total of 141 SNPs were tested in two independent Chinese populations (818 and 809 unrelated Han subjects, respectively) and a Caucasian population (2,286 unrelated subjects). Combining the two Chinese samples, we identified 6 SNPs in FTO to be significantly associated with hip BMD after multiple testing adjustments, with the combined P values ranged from 4.99×10−4–1.47×10−4. These 6 SNPs are all located at the intron 8 of FTO and in high linkage disequilibrium. Each copy of the minor allele of each SNP was associated with increased hip BMD values with the effect size (beta) of ∼0.025 and ∼0.015 in the Chinese sample 1 and 2, respectively. However, none of these 6 SNPs showed significant association signal in the Caucasian sample, by presenting some extent of ethnic difference. Our findings, together with the prior biological evidence, suggest that the FTO gene might be a new candidate for BMD variation and osteoporosis in Chinese populations
Cumulative Effects in 100 kHz Repetition-Rate Laser-Induced Plasma Filaments in Air
[EN] Cumulative effects are crucial for applications of laser filaments, such as for the remote transfer of energy and the control of electric discharges. Up to now, studies of cumulative effects in the air of high-repetition-rate pulse trains have been performed at lower rates than 10 kHz. Herein, the nonlinear effects associated with short plasma filaments produced by pulses of moderate energy (0.4 mJ per pulse) and repetition rates up to 100 kHz are experimentally characterized. With increasing repetition rate, a decrease in absorption, fluorescence emission, and breakdown voltage and concurrently an increase in peak intensity and third-harmonic-generation efficiency are observed. Hydrodynamic simulations of the heated gas show that the observed decreases are directly related to a quasi-stationary state of reduced gas density in the filament. However, further investigations are required to fully understand the physics underpinning the observed sharp reduction of the breakdown voltage at 100 kHz repetition rates. The results may prove relevant for energy and information delivery applications by laser-induced air waveguide or electric discharge and lightning control.TJW acknowledges the support from NSAF (Grant no. U2130123), Strategic Priority Research Program of the Chinese Academy of Sciences (Grant no. XDB16), International Partnership Program of Chinese Academy of Sciences (Grant nos. 181231KYSB20200033 and 181231KYSB20200040), Shanghai Science and Technology Program (Grant no. 21511105000), and Oversea Training Program of Ministry of Science and Technology. MC acknowledges the support from UK Research and Innovation (UKRI) and the UK Engineering and Physical Sciences Research Council (EPSRC) (Fellowship "In-Tempo" EP/S001573/1), and the Royal Society (RGS\R1\201365). JCD acknowledges the support of NASA (SBIR grant 80NSSC22PB067). The authors wish to acknowledge Drs. Jean-Pierre Wolf, Jerome Kasparaian, Clara Saraceno, and Olga Kosareva for enlightening discussions.Wang, T.; Ebrahim, MH.; Afxenti, I.; Adamou, D.; Dada, AC.; Li, R.; Leng, Y.... (2023). Cumulative Effects in 100 kHz Repetition-Rate Laser-Induced Plasma Filaments in Air. Advanced Photonics Research. 4(3). https://doi.org/10.1002/adpr.2022003384
High-resolution programmable scattering for wireless coverage enhancement: an indoor field trial campaign
This paper presents a multi-bit reconfigurable intelligent surface (RIS) with a high phase resolution, capable of beam-steering in the azimuthal plane at sub-6 Gigahertz (GHz). Field trials in realistic indoor deployments have been carried out, with coverage enhancement performance ascertained for three common wireless communication scenarios. Namely, serving users in an open lobby with mixed line of sight and non-line of sight conditions, communication via a junction between long corridors, and a multi-floor scenario with propagation via windows. This work explores the potential for reconfigurable intelligent surface (RIS) deployment to mitigate non-line of sight effects in indoor wireless communications. In a single transmitter, single receiver non-line of sight link, received power improvement of as much as 40 dB is shown to be achievable by suitable placement of a RIS, with an instantaneous bandwidth of at least 100 MHz possible over a 3 to 4.5 GHz range. In addition, the effects of phase resolution on the optimal power reception for the multi-bit RIS have been experimentally verified, with a 2.65 dB improvement compared to a 1-bit case
Pushing the limits of remote RF sensing by reading lips under the face mask
The problem of Lip-reading has become an important research challenge in recent years. The goal is to recognise speech from lip movements. Most of the Lip-reading technologies developed so far are camera-based, which require video recording of the target. However, these technologies have well-known limitations of occlusion and ambient lighting with serious privacy concerns. Furthermore, vision-based technologies are not useful for multi-modal hearing aids in the coronavirus (COVID-19) environment, where face masks have become a norm. This paper aims to solve the fundamental limitations of camera-based systems by proposing a radio frequency (RF) based Lip-reading framework, having an ability to read lips under face masks. The framework employs Wi-Fi and radar technologies as enablers of RF sensing based Lip-reading. A dataset comprising of vowels A, E, I, O, U and empty (static/closed lips) is collected using both technologies, with a face mask. The collected data is used to train machine learning (ML) and deep learning (DL) models. A high classification accuracy of 95% is achieved on the Wi-Fi data utilising neural network (NN) models. Moreover, similar accuracy is achieved by VGG16 deep learning model on the collected radar-based dataset
The characteristics of the spectra of superior venae cavae in patients with right heart failure
BACKGROUND: Aimed to elucidate the characteristics of the spectra of superior venae cavae (SVC) in respiratory cycles in patients with right heart failure. METHODS: The spectra of SVC of 30 patients with right heart failure and 30 paired healthy subjects were recorded through right supraclavicular fossa view. The profiles of spectra of superior venae cavae were observed, and peak velocity and velocity time integral (VTI) of every wave of SVC under spontaneous respiration were measured for statistical analysis. RESULTS: In healthy subjects, the peak velocities and VTI of S wave and D wave increased in inspiratory phase and diminished in expiratory phase, and which of S wave were larger than which of D wave in whole respiratory cycle. In patients with right heart failure, spectral variations of SVC could be classified into three patterns: Pattern I: peak velocities and VTI of S wave were larger than that of D wave in early inspiratory phase, but peak velocities and VTI of D wave were larger than those of S wave in late inspiratory phase and early expiratory phase [Pattern I-1], even in whole respiratory cycle [Pattern I-2]; Pattern II: the S wave disappeared and was substituted by inverse wave with low amplitude in whole respiratory cycle. Pattern III: the profiles of the spectra of SVC in patients were similar to those of healthy subjects. In the whole, the respiratory variation ratios of peak velocities and VTI of S wave and D wave were diminished in patients compared with those in healthy subjects. CONCLUSION: The spectra of superior venae cavae in patients with right heart failure were abnormal, and these characteristics could be used as signs in evaluating right heart failure
CGRPα-Expressing Sensory Neurons Respond to Stimuli that Evoke Sensations of Pain and Itch
Calcitonin gene-related peptide (CGRPα, encoded by Calca) is a classic marker of nociceptive dorsal root ganglia (DRG) neurons. Despite years of research, it is unclear what stimuli these neurons detect in vitro or in vivo. To facilitate functional studies of these neurons, we genetically targeted an axonal tracer (farnesylated enhanced green fluorescent protein; GFP) and a LoxP-stopped cell ablation construct (human diphtheria toxin receptor; DTR) to the Calca locus. In culture, 10–50% (depending on ligand) of all CGRPα-GFP-positive (+) neurons responded to capsaicin, mustard oil, menthol, acidic pH, ATP, and pruritogens (histamine and chloroquine), suggesting a role for peptidergic neurons in detecting noxious stimuli and itch. In contrast, few (2.2±1.3%) CGRPα-GFP+ neurons responded to the TRPM8-selective cooling agent icilin. In adult mice, CGRPα-GFP+ cell bodies were located in the DRG, spinal cord (motor neurons and dorsal horn neurons), brain and thyroid—reproducibly marking all cell types known to express Calca. Half of all CGRPα-GFP+ DRG neurons expressed TRPV1, ∼25% expressed neurofilament-200, <10% contained nonpeptidergic markers (IB4 and Prostatic acid phosphatase) and almost none (<1%) expressed TRPM8. CGRPα-GFP+ neurons innervated the dorsal spinal cord and innervated cutaneous and visceral tissues. This included nerve endings in the epidermis and on guard hairs. Our study provides direct evidence that CGRPα+ DRG neurons respond to agonists that evoke pain and itch and constitute a sensory circuit that is largely distinct from nonpeptidergic circuits and TRPM8+/cool temperature circuits. In future studies, it should be possible to conditionally ablate CGRPα-expressing neurons to evaluate sensory and non-sensory functions for these neurons
ATOMS : ALMA three-millimeter observations of massive star-forming regions - III. Catalogues of candidate hot molecular cores and hyper/ultra compact H II regions
A correction has been published: Monthly Notices of the Royal Astronomical Society, Volume 511, Issue 1, March 2022, Pages 501–505, https://doi.org/10.1093/mnras/stac039We have identified 453 compact dense cores in 3mm continuum emission maps in the ALMA Three-millimetre Observations of Massive Star-forming regions survey, and compiled three catalogues of high-mass star-forming cores. One catalogue, referred to as hyper/ultra compact (H/UC)-HII catalogue, includes 89 cores that enshroud H/UC HII regions as characterized by associated compact H40 alpha emission. A second catalogue, referred to as pure s-cHMC, includes 32 candidate hot molecular cores (HMCs) showing rich spectra (N >= 20 lines) of complex organic molecules (COMs) and not associated with H/UC-HII regions. The third catalogue, referred to as pure w-cHMC, includes 58 candidate HMCs with relatively low levels of COM richness and not associated with H/UC-Hii regions. These three catalogues of dense cores provide an important foundation for future studies of the early stages of high-mass star formation across the Milky Way. We also find that nearly half of H/UC-HII cores are candidate HMCs. From the number counts of COM-containing and H/UC-HII cores, we suggest that the duration of high-mass protostellar cores showing chemically rich features is at least comparable to the lifetime of H/UC-HII regions. For cores in the H/UC-HII catalogue, the width of the H40 alpha line increases as the core size decreases, suggesting that the non-thermal dynamical and/or pressure line-broadening mechanisms dominate on the smaller scales of the H/UC-HII cores.Peer reviewe
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