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With this groundbreaking text, discover how wireless artificial intelligence (AI) can be used to determine position at centimeter level, sense motion and vital signs, and identify events and people. Using a highly innovative approach that employs existing wireless equipment and signal processing techniques to turn multipaths into virtual antennas, combined with the physical principle of time reversal and machine learning, it covers fundamental theory, extensive experimental results, and real practical use cases developed for products and applications. Topics explored include indoor positioning and tracking, wireless sensing and analytics, wireless power transfer and energy efficiency, 5G and next-generation communications, and the connection of large numbers of heterogeneous IoT devices of various bandwidths and capabilities. Demo videos accompanying the book online enhance understanding of these topics. Providing a unified framework for wireless AI, this is an excellent text for graduate students, researchers, and professionals working in wireless sensing, positioning, IoT, machine learning, signal processing and wireless communications.
This study explored the mechanism of Zn-methionine (Zn-Met) influencing eggshell quality of laying hens, and investigated whether the mechanism was related to calcium deposition. Hyline Grey layers (n 384, 38 wk) were divided into four groups: 0 mg Zn/kg, 40, 80 mg Zn/kg as Zn-Met, 80 mg Zn/kg as zinc sulfate (ZnSO4). Eggshell quality, zinc contents, zinc-containing enzymes activities and expressions of shell matrix proteins in eggshell gland (ESG) were analyzed. 80 mg/kg Zn-Met treatment increased (P < 0.05) egg weight and eggshell strength throughout the experiments. 80 mg/kg Zn-Met (P < 0.05) group decreased mammillary knob width and had larger relative atomic weight percentage of Ca, stronger signal intensity of Ca in linear distribution, and the Ca was more evenly distributed in transversal surface of eggshell. Zn contents (P < 0.001) in yolk and serum, Ca, albumin (Alb) levels in ESG as well as carbonic anhydrase (CA) activity in serum (P < 0.05) and mRNA levels of CA and Ca-binding protein-d28k (CaBP-D28k) (P < 0.001) in 80 mg/kg Zn-Met group were the highest among all treatments. In conclusion, shell strength as one of eggshell qualities was mostly related to mammillary cones width in ultrastructure caused by the pattern of calcium deposition in eggshell formation. And the increase of Zn-Met-induced calcium deposition may be due to the increased zinc contents in serum and tissues which were attributable to the increased CA concentrations in serum, Ca, Alb levels and up-regulated CA and CaBP-D28k mRNA levels in ESG.
Staphylococcus aureus has been recognised as one of the important zoonotic pathogens. However, knowledge about the epidemiology and genetic characteristics of S. aureus in rabbits was limited. The aim of this study was to determine the characteristics of 281 S. aureus isolated from dead rabbits of nine rabbit farms in Fujian Province, China. All the isolates were characterised by multi-locus sequencing typing, detection of virulence factors and antimicrobial susceptibility test. The results showed that the 281 isolates were grouped into two sequence types, ST121 (13.52%, 38/281) and ST398 (86.48%, 243/281). Surprisingly, the ST121 strains were only recovered from the lung samples from one of the nine rabbit farms studied. In the 281 isolates, the virulence genes of nuc, hla, hlb, clfA, clfB and fnbpA were positive, whereas the sea, seb, tsst, eta and etb genes were negative. Notably, the 38 ST121 isolates carried the pvl gene. All the 281 isolates were methicillin-susceptible S. aureus, and the isolates were susceptible to most of the used antibiotics, except for streptomycin, kanamycin, azithromycin and penicillin, and the resistance rates of which were 23.84%, 19.57%, 16.01% and 11.03%, respectively. This study first described the epidemiology and characteristics of S. aureus in rabbits in Fujian Province, which will help in tracking the evolution of epidemic strains and preventing the rabbit–human transmission events.
Multidimensional instabilities always develop with time during the process of radiation pressure acceleration, and are detrimental to the generation of monoenergetic proton beams. In this paper, a sharp-front laser is proposed to irradiate a triple-layer target (the proton layer is set between two carbon ion layers) and studied in theory and simulations. It is found that the thin proton layer can be accelerated once to hundreds of MeV with monoenergetic spectra only during the hole-boring (HB) stage. The carbon ions move behind the proton layer in the light-sail (LS) stage, which can shield any further interaction between the rear part of the laser and the proton layer. In this way, proton beam instabilities can be reduced to a certain extent during the entire acceleration process. It is hoped such a mechanism can provide a feasible way to improve the beam quality for proton therapy and other applications.
The present study explores whether embodied meaning is activated in comprehension of action-related Mandarin counterfactual sentences. Participants listened to action-related Mandarin factual or counterfactual sentences describing transfer events (actions towards or away from the participant), and then performed verb-compatible or -incompatible motor action after a transfer verb (action towards or away from the participant) onset. The results demonstrated that motor simulation, specifically the interfering action-sentence compatibility effect (ACE), was obtained in both factual and counterfactual sentences. Additionally, the temporal course of motor resonance was slightly different between factual and counterfactual sentences. We concluded that embodied meaning was activated in action-related Chinese counterfactual sentences. The results supported a neural network model of Chersi, Thill, Ziemke, and Borghi (2010), proposed within the embodiment approach, which explains the interaction between processing action-related sentences and motor performance. Moreover, we speculated that the neural network model of Chersi et al. was also applicable to action-related Mandarin counterfactual comprehension.
The use of electronic cigarettes (e-cigarettes) in smokers with mental health conditions (MHC) is not well understood.
This study aims to compare e-cigarette users and non-users among veteran smokers with MHC to characterize differences in smoking behavior, motivation to quit, psychological distress, primary psychiatric diagnosis, and other factors.
Baseline survey data were used from a randomized smoking cessation trial enrolling smokers with MHC from four Veterans Health Administration hospitals. Participants were categorized as current, former (having ever tried an e-cigarette), or never e-cigarette users. Pearson's χ2 and ANOVA Type-3 F-tests were used to test the bivariate associations between e-cigarette use and variables measured.
Among 1,836 participants, mean age was 58 years (STD ± 12.5), 87% were male, 15% were current e-cigarette users (n = 275), and 27% were former users (n = 503). Sixty-five percent of e-cigarette users reported ‘wanting to quit smoking’ as a primary reason. Mean readiness to quit smoking (1–10) was 7.2, 6.8, and 6.4 for current, former, and never e-cigarette users, respectively (P = 0.0002). Sixty-three percent of current and former users and 55% of never-users reported some mental distress on Kessler-6 scale (P = 0.0003, OR = 1.4, 95% CI 1.1–1.7). A primary psychiatric diagnosis of alcohol or substance use disorder was recorded for 50% of current or former users and 60% of never-users (P = 0.0003, OR = 0.69, 95% CI 0.56–0.84).
E-cigarette users were more ready to quit and most often reported using e-cigarettes to assist with quitting. E-cigarette users had more psychological distress and were less likely to have substance use disorders as their primary psychiatric diagnosis.
High inductive helical support provides a solution to controlling the alignment error of inner electrodes in magnetically insulated transmission lines (MITLs). Three-dimensional particle-in-cell simulations were performed to examine the current loss mechanism and the effects of structural parameters on electron flow in an MITL with a helical inductor. An empirical expression related to the ratio of electron current loss to anode current and the ratio of anode current to self-limited current was obtained. Electron current loss caused by helical inductor with different structures was displayed. The results indicate that the current loss in an MITL, near an inductive helical support, comprises both the inductor current and the electron current loss. The non-uniform structure and current of a helical inductor cause an abrupt change in the magnetic field near the helical support, which leads to anomalous behavior and current loss of electron flow. In addition, current loss in the inductive helical-supported MITL is negligible when the inductance of the support is sufficiently high. This work facilitates the estimation of electron current loss caused by the inductive helical support in MITLs.
Spray-painting equipments are important for the automatic spraying of long conical objects such as rocket fairing. This paper proposes a spray-painting equipment that consists of a feed worktable, a gantry frame and two serial–parallel mechanisms and investigates the optimal design of PRR–PRR parallel manipulator in serial–parallel mechanisms. Based on the kinematic model of the parallel manipulator, the conditioning performance, workspace and accuracy performance indices are defined. The dynamic model is derived using virtual work principle and dynamic evaluation index is defined. The conditioning performance, workspace, accuracy performance and dynamic performance are involved in multi-objective optimization design to determine the optimal geometrical parameters of the parallel manipulator. Furthermore, the geometrical parameters of the gantry frame are optimized. An example is given to show how to determine these parameters by taking a long object with conical surface as painted object.
Fluctuation of pump power is one of the major sources of temporal and intensity noise in femtosecond fiber lasers. In this work, the transfer functions between the relative intensity noise (RIN) of the pump laser diode (LD) and the output RIN, between the RIN of the pump LD and timing jitter of femtosecond fiber lasers are systematically studied. It is demonstrated, for the first time to our knowledge, that the amplitude of the pump RIN transfer function can be effectively decreased by an intra-cavity narrow band-pass filter. In particular, for normal-dispersion lasers, the 3-dB bandwidth of the transfer function can also be narrowed by two-thirds, with a steeper falling edge. Furthermore, with the narrow band-pass filtering, the transfer function is almost independent of the net intra-cavity dispersion due to amplifier similariton formation. The proposed scheme can effectively isolate the pump-induced noise without the need of complex active pump LD control and intra-cavity dispersion management, thus providing an easy way for practical high-power, high-stability femtosecond fiber laser design and related high-precision applications outside the laboratory.
Radiocarbon (14C) has become a unique and powerful tracer in source apportionment of atmospheric carbonaceous particles. In this study, the Asia Pacific Economic Cooperation summit (APEC) held in Beijing in 2014 was used as a demonstration to research the source apportionment of atmosphere PM2.5. We used a 200 kV single stage accelerator mass spectrometer recently completed at China Institute of Atomic Energy (CIAE). The PM2.5 samples related to above case were collected, and the characteristics of radiocarbon in organic carbon (OC) and elemental carbon (EC) in samples were analyzed using the AMS. The results show that the Before-APEC pollution emission mode is different from the During-APEC and After-APEC pollution emission modes. For Before-APEC, During-APEC and After-APEC, the average values of fossil carbon fraction of OC are 0.463, 0.431 and 0.615, respectively, and those of EC are 0.644, 0.561 and 0.687. The fossil source contributions of traffic activities using fossil fuels to OC and EC are 15.8 % and 21.9 %, respectively. The fossil source contributions of industrial activities to OC and EC are 38.0 % and 8.2 %, respectively. It is about 7–10 days that is needed to take to regenerate the PM2.5 pollution caused by human activities.
Map-matching is widely used in automotive navigation systems to locate vehicle positions on a given digital road map. Various map-matching algorithms have been developed focusing on different application needs. Within the Ghosthunter project, a weighting-function-based map-matching algorithm has been developed for detecting wrong-way driving in order to improve road safety, particularly in Autobahn entrance and exit areas. This paper aims at exploring the potential use of lane-level attributes and height data in improving the success rate of the previously presented algorithm. This algorithm performs well in entrance and exit areas to the Autobahn, with a high success rate of 99.5% in identifying the road on which the vehicle is actually travelling. In the enhanced algorithm presented in this paper the weight coefficients used for computing the total weighting score of candidate roads are adjusted with the aid of one or both kinds of these precise data. The results confirmed that the usage of these precise data can effectively help to detect and correct mismatches at junctions and overpasses.
We investigate the conditions that determine the detachment of a water drop from different vibrating textured plates by using vertical vibrations. The plate surfaces were patterned by a lattice of pillars of different shapes with different geometrical arrangements. The acceleration threshold for the water droplet to bounce off the surfaces was measured as a function of the excitation frequency. In each case, the acceleration threshold presents a minimum at the natural frequency of the droplet. The minimum acceleration required for the take-off is larger for small droplets than for large droplets. Namely, one finds that the value of the threshold depends on the size of the droplet and on the maximum apparent contact area between the droplet and the substrate. The theoretical model takes into account the energy necessary to break the capillary bridges between the droplet and the pillars of the surface. This model captures the main ingredients explaining the drop size dependence of the acceleration threshold for the take-off.
SN1991bg-like supernovae are a distinct subclass of thermonuclear Type Ia supernovae (SNe Ia). Their spectral and photometric peculiarities indicate that their progenitors and explosion mechanisms differ from ‘normal’ SNe Ia. One method of determining information about supernova progenitors we cannot directly observe is to observe the stellar population adjacent to the apparent supernova explosion site to infer the distribution of stellar population ages and metallicities. We obtain integral field observations and analyse the spectra extracted from regions of projected radius
about the apparent SN explosion site for 11 91bg-like SNe in both early- and late-type galaxies. We utilise full-spectrum spectral fitting to determine the ages and metallicities of the stellar population within the aperture. We find that the majority of the stellar populations that hosted 91bg-like supernovae have little recent star formation. The ages of the stellar populations suggest that that 91bg-like SN progenitors explode after delay times of >6 Gyr, much longer than the typical delay time of normal SNe Ia, which peaks at
The gut is composed of a single layer of intestinal epithelial cells and plays important roles in the digestion and absorption of nutrients, immune and barrier functions and amino acid metabolism. Weaning stress impairs piglet intestinal epithelium structural and functional integrities, which results in reduced feed intake, growth rates and increased morbidity and mortality. Several measures are needed to maintain swine gut development and growth performance after weaning stress. A large body of evidence indicates that, in weaning piglets, glutamine, a functional amino acid, may improve growth performance and intestinal morphology, reduce oxidative damage, stimulate enterocyte proliferation, modulate cell survival and death and enhance intestinal paracellular permeability. This review focuses on the effects of glutamine on intestinal health in piglets. The aim is to provide evidentiary support for using glutamine as a feed additive to alleviate weaning stress.
The study compared the contributions of self- and social-oriented personality factors to Chinese adolescents’ career exploration with a longitudinal perspective. The mediation effects of career decision self-efficacy and perceived parental support were also investigated. A total of 488 high school students in Hong Kong took three waves of a questionnaire survey at Grade 10, Grade 11 and Grade 12 respectively. The results indicated that adolescents’ career exploration at Grade 12 could be predicted by both self- and social-oriented personalities at Grade 10. Specifically, both self- and social-oriented personality factors could contribute to adolescents’ environmental exploration, and the effect was mediated by perceived parental support at Grade 11, after controlling for the effect of career exploration at Grade 11; whereas self-oriented personality factor could contribute to self-exploration, and the effect was mediated by career self-efficacy at Grade 11. The implications for career counseling and education for Chinese adolescents are discussed.
Altered gut microbial ecology contributes to the development of metabolic diseases including obesity. However, studies based on different populations have generated conflicting results due to diet, environment, methodologies, etc. The aim of our study was to explore the association between gut microbiota and Body Mass Index (BMI) in Chinese college students. 16S next-generation sequencing (NGS) was used to test the gut microbiota of 9 lean, 9 overweight/obesity, and 10 normal-weight male college students. The differences of gut microbiota distribution among three groups were compared, and the relationship between the richness, diversity, composition of gut microbiota and BMI were analyzed. The predominant phyla Bacteroidetes and Firmicutes were further confirmed by real-time PCR. Metagenomic biomarker discovery was conducted by Linear discriminant analysis (LDA) Effect Size (LEfSe). NGS revealed that gut microbiota composition was different among three groups, but there was no difference in the abundance ratio of Firmicutes/ Bacteroidetes. Several bacterial taxa were in linear relationship with BMI (positive relationship: uncultured bacterium (Bacteroides genus); negative relationship: Porphyromonadaceae, Acidaminococcaceae, Rikenellaceae, Desulfovibrionaceae, Blautia, Anaerotruncus, Parabacteroides, Alistipes). Moreover, gut microbiota diversity decreased with the increase of BMI. And LEfSe analyze indicated that Blautia, Anaerotruncus and its uncultured species were significantly enriched in the lean group (LDA score≥3), Parasuterella and its uncultured species were significantly enriched in the overweight/obese groups(LDA score≥3). In general, gut microbiota composition and microbial diversity were associated with BMI in Chinese male college students. Our results might enrich the understanding between gut microbiota and obesity.