This letter investigates the performance of the satellite-terrestrial networks (STN), where a satellite tries to transmit information to a ground user through the help of multiple decode-and-forward ...relays and the existence of co-channel interference sources. In particular, the full-duplex technique and partial relay selection are applied at the relay to increase the total throughput at the destination, enhance the system reliability, and reduce the complexity. In this context, the outage probability (OP) is computed in a closed-form expression. Numerical results are provided to confirm the accuracy of the proposed mathematical framework. Our findings illustrate that the outage performance can be effectively enhanced by increasing either number of relays or transmit power.
Outage probability (OP) and potential throughput (PT) of multihop full-duplex (FD) nonorthogonal multiple access (NOMA) systems are addressed in the present paper. More precisely, two metrics are ...derived in the closed-form expressions under the impact of both imperfect successive interference cancellation (SIC) and imperfect self-interference cancellation. Moreover, to model short transmission distance from the transmit and receive antennae at relays, the near-field path-loss is taken into consideration. Additionally, the impact of the total transmit power on the performance of these metrics is rigorously derived. Furthermore, the mathematical framework of the baseline systems is provided too. Computer-based simulations via the Monte Carlo method are given to verify the accuracy of the proposed framework, confirm our findings, and highlight the benefits of the proposed systems compared with the baseline one.
In the present paper, we investigate the performance of the simultaneous wireless information and power transfer (SWIPT) based cooperative cognitive radio networks (CCRNs). In particular, the outage ...probability is derived in the closed-form expressions under the opportunistic partial relay selection. Different from the conventional CRNs in which the transmit power of the secondary transmitters count merely on the aggregate interference measured on the primary networks, the transmit power of the SWIPT-enabled transmitters is also constrained by the harvested energy. As a result, the mathematical framework involves more correlated random variables and, thus, is of higher complexity. Monte Carlo simulations are given to corroborate the accuracy of the mathematical analysis and to shed light on the behavior of the OP with respect to several important parameters, e.g., the transmit power and the number of relays. Our findings illustrate that increasing the transmit power and/or the number of relays is beneficial for the outage probability.
Simultaneous measurement of proteins and mRNA in single cells enables quantitative understanding and modeling of cellular functions. Here, we present an automated microfluidic system for ...multi-parameter and ultra-sensitive protein/mRNA measurements in single cells. Our technology improves the sensitivity of digital proximity ligation assay by up to 55-fold, with a detection limit of 2277 proteins per cell and with detection efficiency of as few as 29 protein molecules. Our measurements using this system reveal higher mRNA/protein correlation in single mammalian cells than previous estimates. Furthermore, time-lapse imaging of herpes simplex virus 1 infected epithelial cells enabled by our device shows that expression of ICP4 -a major transcription factor regulating hundreds of viral genes- is only partially correlated with viral protein counts, suggesting that many cells go through abortive infection. These results highlight the importance of high-sensitivity protein/mRNA quantification for understanding fundamental molecular mechanisms in individual cells.
During 2005, 764 children were brought to a large children's hospital in Ho Chi Minh City, Vietnam, with a diagnosis of hand, foot, and mouth disease. All enrolled children had specimens (vesicle ...fluid, stool, throat swab) collected for enterovirus isolation by cell culture. An enterovirus was isolated from 411 (53.8%) of the specimens: 173 (42.1%) isolates were identified as human enterovirus 71 (HEV71) and 214 (52.1%) as coxsackievirus A16. Of the identified HEV71 infections, 51 (29.5%) were complicated by acute neurologic disease and 3 (1.7%) were fatal. HEV71 was isolated throughout the year, with a period of higher prevalence in October-November. Phylogenetic analysis of 23 HEV71 isolates showed that during the first half of 2005, viruses belonging to 3 subgenogroups, C1, C4, and a previously undescribed subgenogroup, C5, cocirculated in southern Vietnam. In the second half of the year, viruses belonging to subgenogroup C5 predominated during a period of higher HEV71 activity.
Non-orthogonal multiple access (NOMA) technology is projected to significantly increase the spectrum efficiency of the fifth-generation and subsequent wireless networks. Holographic reconfigurable ...Intelligent surfaces (HRISs) are a revolutionary technology that can deliver excellent spectral and energy efficiency at a cheap cost in wireless networks. In this letter, we investigate the short-packet communication (SPC) with the NOMA-based HRIS system with the internet of things (IoT). A base station (BS) communicates with two NOMA users by using HRIS in the proposed system to enhance spectral efficiency. Furthermore, we derived the exact closed-form expression of the average block error rate (BLER) for two NOMA users. To get more insight into the proposed system, the asymptotic BLER analysis was also carried out at high signal-to-noise ratio regime. The numerical results validate the current analysis and show that the presented NOMA strategy exceeds orthogonal multiple access-based approaches in terms of BLER and throughput.
To enhance the service quality of the unmanned aerial vehicle (UAV), the UAV-aided Internet of Things (IoT) systems could deploy a Deep Neural Network (DNN) for performance prediction for the users. ...Non-orthogonal multiple access (NOMA) is applied to such networks in order to improve spectrum efficiency, and results in improved quality of service at the ground users under the mobility of UAV. The outage and ergodic capacity requirements of the IoT users may not be satisfied due to some imperfect system parameters such as hardware noise. A DNN-based algorithm for performance prediction and the design of multiple antennas at the UAV under hardware noise is proposed. In this DNN-based UAV-NOMA, the central controller (server) collects system parameters periodically based on observing the state of IoT system and performs adjustments to the dynamic environment. The closed-form expressions for the outage probability and the ergodic capacity are derived to evaluate the performance of a group of IoT users. Our numerical results demonstrate that: i) In contrast to the traditional UAV-NOMA system, the UAV cannot know the performance at each IoT user in order to adjust the parameters (i.e. power allocation factors) before transmitting the signals to the devices; while the proposed DNN-based IoT system is capable of predicting the performance; ii) The performance of the IoT users can be significantly improved by integrating more antennas at the UAV and limiting levels of hardware noise; iii) By designing NOMA, the UAV-NOMA-based IoT system can increase the throughput to the tune of 40% compared with the benchmark (the orthogonal multiple access (OMA)-based IoT) .
Secondhand smoke (SHS) has detrimental effects on community health, including coronary heart diseases, stroke, lung cancer etc. This manuscript exploited data from the Vietnam Population-based ...Provincial Global Adult Tobacco Survey (PGATS) in 2022 to update the prevalence of adult exposure to SHS and associated socio-demographic factors.
With the sample size of 71,981 adults aged 15+ throughout 30 provinces and cities in Vietnam, data was collected using the Global Adult Tobacco Survey (GATS) questionnaire. Bivariate analysis and multivariate logistic regression modelling were performed.
In the past 30 days, 44.4% (95% CI: 44.0%-44.9%) adults aged 15+ exposed to SHS at home while 23.1% (95% CI: 22.6%-23.6%) exposed to SHS at work. Female exposure to SHS in the past 30 days was higher at homes but lower at indoor workplaces. Participants aged 15-24 were likely to have higher odds of SHS exposure in the past 30 days to other age groups. Those living in the urban areas had 1.15 times higher odds (95% CI: 1.08-1.22) of exposure to SHS than those in the rural areas. Current smokers tended to have 2.2 times higher odds of exposure to SHS at the indoor workplaces compared to non-smokers (95% CI: 2.05-2.37).
The prevalence of exposure to SHS at home was still relatively high amongst the adult population. While there was a significant reduction of SHS exposure at indoor workplaces, there was a higher prevalence of women being exposed to SHS at home. The Government of Vietnam should continue to strictly implement the smoke-free environment resolution at indoor workplaces and appropriate communication campaigns to protect people, especially women from SHS exposure at homes.
Three new xanthones, garcimckeans A-C (1-3) were isolated from the methanol extract of the stems of Garcinia mckeaniana (Clusiaceae). Their structures were established by extensive spectroscopic ...analysis (HR-ESI-MS and 1 D and 2 D NMR) and by comparison of the spectral data with those reported in the literature. Compounds 1-3 displayed weak cytotoxic activity toward KB, Lu, HepG2, and MCF7 cell lines using the MTT assay with IC
50
values ranging from 71.03 ± 2.93 to 90.40 ± 7.13 µM compared to that of the positive control compound, ellipticine (IC
50
: 1.22 ± 0.10 ∼ 2.44 ± 0.2 µM).
The coronavirus disease 2019 (COVID-19) pandemic has increased the workload of healthcare workers (HCWs), impacting their health. This study aimed to assess sleep quality using the Pittsburgh Sleep ...Quality Index (PSQI) and identify factors associated with poor sleep among HCWs in Vietnam during the COVID-19 pandemic.
In this cross-sectional study, 1000 frontline HCWs were recruited from various healthcare facilities in Vietnam between October 2021 and November 2021. Data were collected using a 3-part self-administered questionnaire, which covered demographics, sleep quality, and factors related to poor sleep. Poor sleep quality was defined as a total PSQI score of 5 or higher.
Participants' mean age was 33.20±6.81 years (range, 20.0-61.0), and 63.0% were women. The median work experience was 8.54±6.30 years. Approximately 6.3% had chronic comorbidities, such as hypertension and diabetes mellitus. About 59.5% were directly responsible for patient care and treatment, while 7.1% worked in tracing and sampling. A total of 73.8% reported poor sleep quality. Multivariate logistic regression revealed significant associations between poor sleep quality and the presence of chronic comorbidities (odds ratio OR, 2.34; 95% confidence interval CI, 1.17 to 5.24), being a frontline HCW directly involved in patient care and treatment (OR, 1.59; 95% CI, 1.16 to 2.16), increased working hours (OR, 1.84; 95% CI,1.37 to 2.48), and a higher frequency of encountering critically ill and dying patients (OR, 1.42; 95% CI, 1.03 to 1.95).
The high prevalence of poor sleep among HCWs in Vietnam during the COVID-19 pandemic was similar to that in other countries. Working conditions should be adjusted to improve sleep quality among this population.
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