Identification of discharge regimes of cyclone dipleg-trickle valve system based on pressure fluctuation profiles

An experiment was conducted on the Φ150mm×5000mmcyclone dipleg-trickle valve setup, which was focused on analyzing the discharge characteristics of trickle valve of cyclone dipleg by means of the dynamic pressure measurement. The effects of two operating parameters, negative pressure drop (0~11kPa) and solids flux rate (0~50 kg/m2.s), on the discharge patterns were investigated. The experimental results show that there are two kinds of discharge patterns in the trickle valve. One is continuous trickling discharge at low negative pressure drop and high solids flux rate, which is characterized by valve plate opening continuously, and the measured pressure with high frequency and low amplitude. The other is intermittent periodic dumping discharge at high negative pressure drop and low solids flux rate, which has the properties of valve plate opening interval, and the measured pressure with low frequency and high amplitude. The two discharge patterns could transform each other as varying the negative pressure drop or solids flux rate. The discharge regime map was proposed based on the experimental data, which is related to the negative. Please click Additional Files below to see the full abstract

STDA-Meta: A Meta-Learning Framework for Few-Shot Traffic Prediction

As the development of cities, traffic congestion becomes an increasingly pressing issue, and traffic prediction is a classic method to relieve that issue. Traffic prediction is one specific application of spatio-temporal prediction learning, like taxi scheduling, weather prediction, and ship trajectory prediction. Against these problems, classical spatio-temporal prediction learning methods including deep learning, require large amounts of training data. In reality, some newly developed cities with insufficient sensors would not hold that assumption, and the data scarcity makes predictive performance worse. In such situation, the learning method on insufficient data is known as few-shot learning (FSL), and the FSL of traffic prediction remains challenges. On the one hand, graph structures' irregularity and dynamic nature of graphs cannot hold the performance of spatio-temporal learning method. On the other hand, conventional domain adaptation methods cannot work well on insufficient training data, when transferring knowledge from different domains to the intended target domain.To address these challenges, we propose a novel spatio-temporal domain adaptation (STDA) method that learns transferable spatio-temporal meta-knowledge from data-sufficient cities in an adversarial manner. This learned meta-knowledge can improve the prediction performance of data-scarce cities. Specifically, we train the STDA model using a Model-Agnostic Meta-Learning (MAML) based episode learning process, which is a model-agnostic meta-learning framework that enables the model to solve new learning tasks using only a small number of training samples. We conduct numerous experiments on four traffic prediction datasets, and our results show that the prediction performance of our model has improved by 7\% compared to baseline models on the two metrics of MAE and RMSE

Resistance of Enterococcus spp. in Dust From Farm Animal Houses: A Retrospective Study

In a retrospective study, the antimicrobial susceptibility of Enterococcus spp. isolated from stored sedimentation dust samples from cattle, pig and poultry barns to 16 antibiotics was determined using a microdilution test. The resistance phenotypes of 70 isolates from different timespans (8 from the 1980s, 15 from the 1990s, 43 from the 2000s and 4 from 2015) were determined. Resistant enterococci were detected in samples from all time periods. Resistances to three or more antibiotics occurred in 69 percent of all isolates. The oldest multidrug resistant isolate was an Enterococcus faecium obtained from a 35-year-old pig barn dust sample. No correlations (ρ = 0.16, p = 0.187) were found between the age of isolates and the number of resistances. Instead, the number of resistances was associated with the origin of the isolates. An exact logistic conditional regression analysis showed significant differences in resistance to ciprofloxacin, erythromycin, penicillin and tylosin between isolates from different animal groups. Interestingly, we isolated ciprofloxacin-resistant E. faecium from pig barn dust before fluoroquinolones were introduced into the market for use in animal husbandry. In conclusion, dust from farm animal houses is a reservoir and carrier of multidrug-resistant Enterococcus spp. People working in barns are unavoidably exposed to these bacteria. Furthermore, it can be hypothesized that emissions from barns of intensive livestock farming contaminate the environment with multidrug resistant enterococci

Guinea Pig Model for Evaluating the Potential Public Health Risk of Swine and Avian Influenza Viruses

BACKGROUND: The influenza viruses circulating in animals sporadically transmit to humans and pose pandemic threats. Animal models to evaluate the potential public health risk potential of these viruses are needed. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the guinea pig as a mammalian model for the study of the replication and transmission characteristics of selected swine H1N1, H1N2, H3N2 and avian H9N2 influenza viruses, compared to those of pandemic (H1N1) 2009 and seasonal human H1N1, H3N2 influenza viruses. The swine and avian influenza viruses investigated were restricted to the respiratory system of guinea pigs and shed at high titers in nasal tracts without prior adaptation, similar to human strains. None of the swine and avian influenza viruses showed transmissibility among guinea pigs; in contrast, pandemic (H1N1) 2009 virus transmitted from infected guinea pigs to all animals and seasonal human influenza viruses could also horizontally transmit in guinea pigs. The analysis of the receptor distribution in the guinea pig respiratory tissues by lectin histochemistry indicated that both SAα2,3-Gal and SAα2,6-Gal receptors widely presented in the nasal tract and the trachea, while SAα2,3-Gal receptor was the main receptor in the lung. CONCLUSIONS/SIGNIFICANCE: We propose that the guinea pig could serve as a useful mammalian model to evaluate the potential public health threat of swine and avian influenza viruses

Ship Bridge OOW Activity Status Detection Using Wi-Fi Beamforming Feedback Information

Officers on Watch (OOWs) of the ship’s bridge play a vital role in maritime navigation safety, monitoring the ship’s navigational status, and ensuring maritime safety. The status of inactive watch officers, such as fatigued driving and negligence on lookout, is one of the main causes of accidents. Intelligent technology for real-time perception and state evaluation of ship OOWs significantly reduces accidents caused by human factors. The traditional computer vision method is difficult to adapt to the complex environment of a ship bridge, and carries strong privacy risks. With the development of Internet of Things technology, sensing technology based on ubiquitous Wi-Fi devices provides a new way to accurately monitor the status of ship OOWs. In this paper, we use commercial off-the-shelf (COTS) Wi-Fi devices to propose a ship driving activity state detection method based on beamforming feedback information (BFI). Using wireless sensing data to sense the number of OOWs and their driving behavior realizes low-cost and high-precision detection of the behavioral status of the ship’s bridge watchkeeper. Experiments were conducted in a ship-driving simulation laboratory and on a real-world Yangtze River cruise ship. The experimental results demonstrate that our proposed method achieves 92.4% and 98.1% accuracy for tracking active status and estimating the number of OOWs, respectively

Analysis of In Vivo Transcriptome of Intracellular Bacterial Pathogen Salmonella enterica serovar Typhmurium Isolated from Mouse Spleen

Salmonella enterica serovar Typhimurium (S. Typhimurium) is an important intracellular pathogen that poses a health threat to humans. This study tries to clarify the mechanism of Salmonella survival and reproduction in the host. In this study, high-throughput sequencing analysis was performed on RNA extracted from the strains isolated from infected mouse spleens and an S. Typhimurium reference strain (ATCC 14028) based on the BGISEQ-500 platform. A total of 1340 significant differentially expressed genes (DEGs) were screened. Functional annotation revealed DEGs associated with regulation, metabolism, transport and binding, pathogenesis, and motility. Through data mining and literature retrieval, 26 of the 58 upregulated DEGs (FPKM > 10) were not reported to be related to the adaptation to intracellular survival and were classified as candidate key genes (CKGs) for survival and proliferation in vivo. Our data contribute to our understanding of the mechanisms used by Salmonella to regulate virulence gene expression whilst replicating inside mammalian cells

Synthesis and Comparative Biological Properties of Ag-PEG Nanoparticles with Tunable Morphologies from Janus to Multi-Core Shell Structure

Silver nanoparticles synthesized with polymers as coating agents is an effective method to overcome their poor stability and aggregation in solution. Silver-polyethylene glycol (Ag-PEG) nanoparticles were synthesized with the thiol-functionalized polyethylene glycol (SH-PEA) as the coating, reducing and stabilizing agent. The UV irradiation time, polymer and silver nitrate concentration for the synthesis were investigated. The concentration of silver nitrate had significant effect on the morphology of Ag-PEG nanoparticles. When increasing the concentration of silver nitrate, SEM and TEM images showed that Ag-PEG nanoparticles changed from Janus to multi-core shell structure. Meanwhile, pure silver particles in the two hybrid nanoparticles presented spherical shape and had the similar size of 15 nm. The antibacterial activities and cytotoxicity of the two structural Ag-PEG nanoparticles were investigated to understand colloid morphology effect on the properties of AgNPs. The results of antibacterial activities showed that the two structural Ag-PEG nanoparticles exhibited strong antibacterial activities against Staphylococcus aureus, Escherichia coli and Bacillus subtilis. The Janus nanoparticles had larger minimal inhibitory concentration (MIC) and minimum bacterial concentration (MBC) values than the multi-core shell counterparts. The results of cytotoxicity showed the Janus Ag-PEG nanoparticles had lower toxicity than the multi-core shell nanoparticles

Characteristics and Epidemiological Investigation of Paratuberculosis in Dairy Cattle in Tai’an, China

Paratuberculosis, a chronic and sometimes fatal disease of ruminants, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). In this study, we examined paratuberculosis cases among 2–4-year-old dairy cows at farms in Shandong Province, China. Paratuberculosis cases were diagnosed based on clinical symptoms, pathological autopsy, and histopathological inspection. Characteristics of paratuberculosis in the affected dairy cattle included poor body condition, persistent diarrhea, subcutaneous edema, granulomatous ileitis (multibacillary), mesenteric lymphadenitis, and hepatitis. Acid-fast bacilli from fecal specimens and lymphocytes were putatively identified as MAP based on Ziehl-Neelsen staining, then confirmed using polymerase chain reaction-based testing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses. Overall, only one MAP strain was isolated from a herd with symptomatic diarrhea. However, analysis of 586 serum samples from nine herds in Tai’an City revealed that 66.7% of herds and 14.2% of animals were seropositive for MAP. Our findings suggest that paratuberculosis is widely prevalent and therefore a significant threat to the dairy industry in Tai’an City, Shandong Province, China

A fully integrated Class-J GaN MMIC power amplifier for 5-GHz WLAN 802.11ax application

This letter presents a fully integrated Class-J GaN monolithic microwave circuit power amplifier (PA), which is fabricated in Woolfspeed 0.25-μm GaN-on-SiC technology. This PA is the first published design for the emerging IEEE 802.11ax application in the literature. When tested with 80-MHz 256-quadratic-amplitude modulation 802.11ax signal with 11.25-dB peak-to-average power ratio, the PA delivers average output power of 27.3-30.3 dBm from 4.9 to 5.9 GHz, with power-added efficiency of 16.7% to 27.3%, while meeting the standard specification of error vector magnitude below -32 dB.Accepted versio

A novel 2.6–6.4 GHz highly integrated broadband GaN power amplifier

In this letter, a novel methodology to achieve output broadband matching is proposed. Based on this methodology, a broadband gallium nitride power amplifier (PA) with input matching and stabilization circuit integrated on-chip is designed. The implemented PA achieves a maximum drain efficiency of 62%-79.2% from 2.6 to 6.4 GHz (84.4% fractional bandwidth), with a saturated output power (Psat) of 34.3-35.8 dBm, while providing a gain larger than 10 dB. When tested with 802.11ac VHT80 MC9 (80 MHz, 256-QAM) with 11.3-dB peak-to-average power ratio, PA achieves a drain efficiency of 22.1%-25.2% with an average output power of 23-25.4 dBm across the whole band, while meeting the standard specification of error vector magnitude below -32 dB.NRF (Natl Research Foundation, S’pore)Accepted versio