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In vehicular networks, the safety-related messages (emergency and periodic messages) and non-safety message (RFS: request for service message) should share the scarce wireless resource. Emergency messages deliver time-critical information with guaranteed reliability, e.g. road-safety information, whereas periodic ones convey normal status update information, e.g. vehicular positions, show that is less time- and loss-critical. The RFS message is used for reserving Internet data service through the infrastructure on the road. In the channel access for vehicles, the synchronization interval (SI) is repeated every 100 ms and each SI is divided by one control channel interval (CCHI) for the transmission of safety-related messages and RFS message and by one service channel interval (SCHI) for the Internet service from the roadside infrastructure. It is crucial to set the length of CCHI appropriately in the SI because of the dynamic environment of VANETs. In this paper, we consider two optimization problems of message transmissions depending on whether the length of CCHI is flexible or not: 1) a fixed CCHI (non-adaptive) and 2) a variable CCHI (adaptive), respectively, and obtain the optimal MAC parameters where we adopt the IEEE 802.11e enhanced distributed channel access (EDCA) protocol with a “strict” priority for the emergency message. Finally, we conduct extensive simulations to validate our analytical findings.

Abstract Functional capacity is an important objective health metric, and relies on the maintenance of physiological homeostasis. Autonomic nervous system is known to coordinates the maintenance of multi-organ homeostasis. The objective of this study was to examine the association of autonomic nervous system function with functional capacity in adults aged 55 years and older. A cohort of 542 adults (mean age of 70.1 years) received repeated measurements of heart rate variability, an autonomic nervous system function marker, and chair rise time, a functional capacity measure. Linear mixed models analysis showed that 1 SD lower powers in low-frequency range at baseline was associated with a 0.11 (95% CI 0.01–0.21) s/year faster increase in chair rise time during the follow-up, whereas 1 SD increase in powers in high-frequency range and 1 SD decrease in the ratio of powers in low-frequency range to powers in high-frequency range during the follow-up were associated with a 0.22 (95% CI 0.06–0.39) s and 0.17 (95% CI 0.01–0.33) s increase in chair rise time. In conclusion, autonomic nervous system function and its changes were longitudinally associated with changes in functional capacity in older adults.

Coronavirus disease 2019 is a public health challenge requiring rapid testing for the detection of infections and transmission. Nucleic acid amplification tests targeting SARS coronavirus 2 (CoV2) are used to detect CoV2 in clinical samples. Real-time reverse transcription quantitative PCR is the standard nucleic acid amplification test for CoV2, although reverse transcription loop-mediated isothermal amplification is used in diagnostics. The authors demonstrate a sequence-specific reverse transcription loop-mediated isothermal amplification-based nucleic acid amplification assay that is finished within 30 min using minimally processed clinical nasal swab samples and describe a fluorescence-quenched reverse transcription loop-mediated isothermal amplification assay using labeled primers and a quencher oligonucleotide. This assay can achieve rapid (30 min) and sensitive (1000 plaque-forming units/ml) fluorescence detection of CoV2 (WA1/2020), B.1.1.7 (Alpha) and variants of concern Delta (B.1.617.2) and Omicron (B.1.1.529) in nasal samples.

Finding creative new ideas requires both release from fixationand a productive search mindset. Recent research has shownthat messy desks, walking, and mind-wandering can lead tomore new uses for old objects. Here we show that a human-centric mindset is superior to mind-wandering for generatingmore alternative uses and more creative uses because itprovides both release from fixation and an effective searchstrategy. A human-centric mindset entails perspective-taking,and perspective-taking is likely to be an effective generalstrategy for enhancing creativity, problem-solving andinnovation.

We present a subspace-based polynomial rooting algorithm to estimate the frequency bias (FB) of generalized frequency division multiplexing (GFDM) systems employing null subcarriers and repetitive sub-symbols. The estimation process is classified into fractional FB (FFB) and integer FB (IFB) estimation. The use of repetitive sub-symbols creates a quasi-periodic structure in the FB-distorted received signal, allowing the proposed algorithm to estimate the FFB using the root-MUSIC algorithm. Based on this, the proposed algorithm compensates for the FFB in the received signal and then estimates the null subcarrier pattern (NSP) in the frequency domain. As a result, the IFB estimate can be obtained in a maximum likelihood (ML) manner. Before the NSP estimation, this study uses a sub-symbol combiner to enhance signal strength of the FFB-aligned signal, ensuring the reliability of the IFB estimate. Computer simulations show that the proposed subspace-based algorithm has several advantages over traditional FB estimation methods: 1. Unlike some existing algorithms that use a training sequence to estimate FB, the proposed approach is a semi-blind algorithm because it can deliver information through repeated sub-symbols while estimating FB; 2. The proposed algorithm demonstrates excellent estimation accuracy compared to most traditional FB estimation algorithms; and 3. The proposed algorithm is computationally efficient, making it applicable to real-time applications in future communication systems. [ABSTRACT FROM AUTHOR]

As the COVID-19 pandemic continued unabatedly, many global supply chains involved in manufacturing and distributing personal protective equipment often failed to meet surge demand due to production capacity limits. Before the COVID-19 pandemic, the existing medical mask supply chain in Taiwan was decentralized, but immediately following the outbreak in 2020, the government of Taiwan established a centralized virtual company that integrated production, distribution, and sales. We use an exploratory empirical case study to gain insights into Taiwan's innovative public-private collaboration and the relationship between collaborative activities and supply chain resilience. This paper examines how a ten-fold growth, from 1.88 million to 20 million, in the daily production of medical masks, and their equitable distribution was achieved within four months of the onset of the COVID-19 pandemic. The results indicate that the public-private collaboration through a government-led centralized supply chain mitigated the impacts of unpredictable disruptions, built supply chain resilience, and ensured mask availability to the public. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are porous materials with potential in biomedical applications such as sensing, drug delivery, and radiosensitization. However, how to tune the properties of the MOFs for such applications remains challenging. Herein, we synthesized two MOFs, Zr-PEB and Hf-PEB. Zr-PEB can be classified as porous interpenetrated zirconium frameworks (PIZOFs) and Hf-PEB is its analogue. We controlled their sizes while maintaining their crystal structure by employing a coordination modulation strategy. They were designed to serve as sensitizer for X-ray therapy and as potential drug carriers. Comprehensive characterizations of the MOFs' properties have been conducted, and the in vitro biological impacts have been studied. Since viability assay showed that Hf-PEB was more biocompatible compared to Zr-PEB, the cellular uptake of Hf-PEB by cells was evaluated using both fluorescence microscopy and soft X-ray tomography (SXT), and the three-dimensional structure of Hf-PEB in cells was observed. The results revealed the potential of Zr-PEB and Hf-PEB as nanomaterials for biomedical applications and demonstrated that SXT is an effective tool to assist the development of such materials. [ABSTRACT FROM AUTHOR]

Background: Traumatic and thermal injuries result in a state of systemic immune suppression, yet the mechanisms that underlie its development are poorly understood. Released from injured muscle and lysed red blood cells, heme is a damage associated molecular pattern with potent immune modulatory properties. Here, we measured plasma concentrations of total heme in over 200 traumatic and thermally-injured patients in order to examine its relationship with clinical outcomes and post-injury immune suppression. Methods: Blood samples were collected from 98 burns (=15% total body surface area) and 147 traumatically-injured (injury severity score =8) patients across the ultra-early (=1 hour) and acute (4-72 hours) post-injury settings. Proinflammatory cytokine production by lipopolysaccharide (LPS) challenged whole blood leukocytes was studied, and plasma concentrations of total heme, and its scavengers haptoglobin, hemopexin and albumin measured, alongside the expression of heme-oxygenase-1 (HO-1) in peripheral blood mononuclear cells (PBMCs). LPS-induced tumour necrosis factor-alpha (TNFα) production by THP-1 cells and monocytes following in vitro heme treatment was also examined. Results: Burns and traumatic injury resulted in significantly elevated plasma concentrations of heme, which coincided with reduced levels of hemopexin and albumin, and correlated positively with circulating levels of pro and antiinflammatory cytokines. PBMCs isolated from trauma patients 4-12 and 48-72 hours post-injury exhibited increased HO-1 gene expression. Non-survivors of burn injury and patients who developed sepsis, presented on day 1 with significantly elevated heme levels, with a difference of 6.5 µM in heme concentrations corresponding to a relative 52% increase in the odds of postburn mortality. On day 1 post-burn, heme levels were negatively associated with ex vivo LPS-induced TNF-α and interleukin-6 production by whole blood leukocytes. THP-1 cells and monocytes pre-treated with heme exhibited significantly reduced TNF-α production following LPS stimulation. This impairment was associated with decreased gene transcription, reduced activation of extracellular signal-regulated kinase 1/2 and an impaired glycolytic response. Conclusions: Major injury results in elevated plasma concentrations of total heme that may contribute to the development of endotoxin tolerance and increase the risk of poor clinical outcomes. Restoration of the heme scavenging system could be a therapeutic approach by which to improve immune function post-injury. [ABSTRACT FROM AUTHOR]