Silver nanoparticles (AgNPs) are widely used due to their unique antibacterial properties and excellent photoelectric properties. Wastewater treatment plants form a pool of AgNPs due to the social ...cycle of wastewater. During biological treatment processes, the particle size and stability of AgNPs change. We studied the particle size changes and stability of silver nanoparticles in the presence of bovine serum albumin (BSA) and humic acid (HA). The experimental results indicated that silver nanoparticles can complex with the functional groups in BSA. For AgNP-BSA composites, as the BSA concentration increases, the size of the silver nanoparticles first decreases and then increases. AgNPs can combine with the amide, amino, and carboxyl groups in HA. As the concentration of HA increases, the particle size and large particle size distribution of AgNPs increase. This increasing trend is more obvious when the HA concentration is lower than 20 mg L
−1
. When HA and BSA exist at the same time, HA will occupy the adsorption sites of BSA on the surface of AgNPs, and the AgNP-HA complex will dominate the system. This study aims to provide key operational control strategies for the process operation of wastewater treatment plants containing AgNPs and theoretical support for promoting water environment improvement and economic development such as tourism.
Silver nanoparticles (AgNPs) are widely used due to their unique antibacterial properties and excellent photoelectric properties.
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•A novel HT-qPCR chip to quantify the abundances of targeted VFGs in the environment.•96 VFGs from representative pathogenic bacteria are targeted by 120 primer pairs.•69 VFGs were ...detected when applying the VFG-Chip to a wastewater treatment system.
As zoonotic pathogens are threatening public health globally, the virulence factor genes (VFGs) they carry underlie latent risk in the environment. However, profiling VFGs in the environment is still in its infancy due to lack of efficient and reliable quantification tools. Here, we developed a novel high-throughput qPCR (HT-qPCR) chip, termed as VFG-Chip, to comprehensively quantify the abundances of targeted VFGs in the environment. A total of 96 VFGs from four bacterial pathogens including Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, and Salmonella enterica were targeted by 120 primer pairs, which were involved in encoding five types of virulence factors (VFs) like toxin, adherence, secretion system, immune evasion/invasion, and iron uptake. The specificity of VFG-Chip was both verified computationally and experimentally, with high identity of amplicon sequencing and melting curves analysis proving its robust capability. The VFG-Chip also displayed high sensitivity (by plasmid serial dilution test) and amplification efficiency averaging 97.7%. We successfully applied the VFG-Chip to profile the distribution of VFGs along a wastewater treatment system with 69 VFGs detected in total. Overall, the VFG-Chip provides a robust tool for comprehensively quantifying VFGs in the environment, and thus provides novel information in assessing the health risks of zoonotic pathogens in the environment.
The physiological effects of prone ventilation in ARDS patients have been discussed for a long time but have not been fully elucidated. Electrical impedance tomography (EIT) has emerged as a tool for ...bedside monitoring of pulmonary ventilation and perfusion, allowing the opportunity to obtain data. This study aimed to investigate the effect of prone positioning (PP) on ventilation-perfusion matching by contrast-enhanced EIT in patients with ARDS.
Monocenter prospective physiologic study.
University medical ICU.
Ten mechanically ventilated ARDS patients who underwent PP.
We performed EIT evaluation at the initiation of PP, 3 h after PP initiation and the end of PP during the first PP session.
The regional distribution of ventilation and perfusion was analyzed based on EIT images and compared to the clinical variables regarding respiratory and hemodynamic status. Prolonged prone ventilation improved oxygenation in the ARDS patients. Based on EIT measurements, the distribution of ventilation was homogenized and dorsal lung ventilation was significantly improved by PP administration, while the effect of PP on lung perfusion was relatively mild, with increased dorsal lung perfusion observed. The ventilation-perfusion matched region was found to increase and correlate with the increased PaO
/FiO
by PP, which was attributed mainly to reduced shunt in the lung.
Prolonged prone ventilation increased dorsal ventilation and perfusion, which resulted in improved ventilation-perfusion matching and oxygenation.
ClinicalTrials.gov, NCT04725227. Registered on 25 January 2021.
The 27th edition of the International Conference on Real-Time Networks and Systems (RTNS) was held November 6–8, 2019, in Toulouse, France. RTNS is a friendly conference with a great sense of ...community that offers excellent opportunities for collaboration as well as a high-quality technical program. RTNS publishes papers addressing real-time issues in any area of computation and communication, at any level of abstraction, and in any application domain. The reviewing process involved 44 program committee members, who were assisted by 22 additional reviewers, and each submission received at least three reviews. Of 37 submissions that were received, 20 papers were accepted for publication at RTNS 2019.From the 20 accepted papers, 4 were chosen as outstanding papers, and the authors of those papers were invited to submit extended articles for this special issue, containing significant additional technical content beyond the contributions that were published at RTNS 2019. Each of those articles underwent a rigorous additional review process, involving new reviewers who had not originally reviewed the papers, as well as reviewers who had evaluated them for RTNS 2019, and with each article receiving three reviews in this stage as well. Following multiple rounds of reviewing and revision, leading ultimately to approval, each of the four articles that appears in this special issue provides new technical advances in the state of the art for real-time networks and systems.
Background
The effects of high flow nasal cannula (HFNC) on postoperative patients at high risk for pulmonary complications(PC) are controversial. We aimed to further determine the effectiveness of ...HFNC in postoperative patients at high risk for PC by comparison to conventional oxygen therapy (COT).
Methods
We performed a comprehensive search that compared HFNC with COT in postoperative patients at high risk for PC. The main outcomes were length of hospital stay (hospital LOS) and respiratory complications.
Results
Six trials with a total of 733 patients were pooled in our final studies. Except for Hospital LOS (I2 = 53%, χ2 = 8.51, P = .07) and rate of intubation or non‐invasive ventilation (NIV) for respiratory failure (RF) (I2 = 49%, χ2 = 1.97, P = .16) between HFNC and COT, no significant heterogeneity was found in outcome measures. Compared with COT, HFNC was associated with a lower rate of intubation or NIV for RF (RR 0.23, 95% CI 0.08‐0.66, P = .006) and rate of hypercapnia (RR 0.37, 95% CI 0.20‐0.68, P = .002). As for the Hospital LOS, ICU LOS, rate of requirement of O2 after discontinuous and hypoxemia, HFNC did not show any advantage over COT. Trial Sequential Analysis (TSA) for Hospital LOS showed that monitoring boundaries were finally not surpassed and required information size (RIS) was not met.
Conclusions
The available randomised controlled trials (RCTs) suggest that, among the postoperative patients at high risk for PC, HFNC therapy compared with the COT significantly reduces rate of incubation or NIV for RF and rate of hypercapnia, meanwhile is safely administered. Further large‐scale, multicenter, randomised and controlled studies are needed to confirm our results.
Long Range Wide Area Network (LoRaWAN) offers a wide range communication with low power consumption at the cost of low throughput. Although this technology is well suited to IoT applications, it ...faces scalability and reliability limitations because it is based on the Aloha random access protocol on one hand and on random choice of a channel and a spreading factor (SF) on the other hand. LoRaWAN recommends the use of Adaptive Data Rate (ADR) mechanism to optimize the global network utilization by adjusting the node’s configuration (Spreading Factor, Transmission Power, Data rate, etc.). However, ADR is defined for fixed nodes and doesn’t handle the node’s mobility. We proposed in previous work, an enhanced ADR mechanism (E-ADR) that takes into account the movement of the device and its position to define the optimal data rate to use. Despite the performance improvement of LoRaWAN thanks to E-ADR, collisions are happened due to simultaneous transmissions with the same configuration (channel, SF). A best practice to reduce collisions and improve performance in mobile networks is the use of time slotted communication. Several research papers proposed time slotted schemes for LoRaWAN, however none of them considered the case of mobile nodes. Therefore, in this work, we propose ETS-LoRaWAN (Enhanced Time Slotted LoRaWAN), a dynamic collision free time slotted approach to determine respectively the best SF according to the node’s position, the time slot, and the channel to use. Our experimental results show performance improvement of ETS-LoRaWAN compared to Aloha LoRaWAN by reducing the Packet Loss Ratio (PLR) and the energy consumption.
With the ever growing internet of things market, Low Power Wide Area Networks (LPWAN) become more and more attractive. Among the various LPWAN technologies, LoRa (and LoRaWAN) has drawn a lot of ...research attention with its great adaptation capability. In fact, its spectrum modulation spreading factor, transmission power, data rate, channel bandwidth, and coding rate are so many configurable parameters allowing to cope with a large number of use cases. In addition, through its ADR (Adaptive Data Rate) function, LoRa offers an interesting mechanism to self-adapt its configuration to its operational conditions. Several works have been carried out for extending ADR to further improve its performance for different use cases. LoRa has even been recently investigated on its capacity to support the mobility, although it is not originally designed for. In this paper, we first review the most significant ADR enhancements proposed in the literature, then describe our earlier E-ADR proposal
1
aiming at dealing with the node mobility use case. This paper also provides experimental performance evaluations of the reviewed ADR enhancements in a mobile node scenario, highlighting the unique feature of E-ADR.
To improve the understanding of dissolved organic nitrogen (DON) variation characteristics in a biological aerated filter (BAF) used for drinking water treatment, this study investigated the effects ...of gas–water ratios (0, 0.5:1, 2:1, and 10:1), a controlling factor of BAF operation, on DON characteristics. The dissolved organic carbon (DOC) removal efficiency in the BAF was consistent with DON concentration and increased as the gas–water ratio increased to a certain point, above which the increase gradually decreased. The optimal gas–water ratio in this study was considered to be 2:1 from the perspective of DOC removal and DON reduction. Use of fluorescence regional integration (FRI) and parallel factor (PARAFAC) model to analyze the effects of the gas–water ratio on the spectral characteristics of DON revealed that humic acid-like substances were not sensitive to the gas–water ratio, while protein-like substances were more sensitive. Increasing the gas–water ratio was beneficial to the reduction of biodegradable DON. Correlation analysis showed that the results obtained using FRI were consistent with those obtained using the PARAFAC model under different gas–water ratios.
In this paper, we propose a fast and accurate deep network-based object tracking method, which combines feature representation, template tracking and foreground detection into a single framework for ...robust tracking. The proposed framework consists of a backbone network, which feeds into two parallel networks, TmpNet for template tracking and FgNet for foreground detection. The backbone network is a pre-trained modified VGG network, in which a few parameters need to be fine-tuned for adapting to the tracked object. FgNet is a fully convolutional network to distinguish the foreground from background in a pixel-to-pixel manner. The parameter in TmpNet is the learned channel-wise target template, which initializes in the first frame and performs fast template tracking in the test frames. To enable each component to work closely with each other, we use a multi-task loss to end-to-end train the proposed framework. In online tracking, we combine the score maps from TmpNet and FgNet to find the optimal tracking results. Experimental results on object tracking benchmarks demonstrate that our approach achieves favorable tracking accuracy against the state-of-the-art trackers while running at a real-time speed of 38 fps.
The recent advancements of technology in robotics and wireless communication have enabled the low-cost and large-scale deployment of mobile sensor nodes for target tracking, which is a critical ...application scenario of wireless sensor networks. Due to the constraints of limited sensing range, it is of great importance to design node coordination mechanism for reliable tracking so that at least the target can always be detected with a high probability, while the total network energy cost can be reduced for longer network lifetime. In this paper, we deal with this problem considering both the unreliable wireless channel and the network energy constraint. We transfer the original problem into a dynamic coverage problem and decompose it into two subproblems. By exploiting the online estimate of target location, we first decide the locations where the mobile nodes should move into so that the reliable tracking can be guaranteed. Then, we assign different nodes to each location in order that the total energy cost in terms of moving distance can be minimized. Extensive simulations under various system settings are employed to evaluate the effectiveness of our solution.
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