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This paper proposes a dual-band wearable monopole antenna adopting an electromagnetic bandgap (EBG) structure, which operates at 2.45 and 5.8 GHz ISM bands and is suitable for wearable applications. Both the monopole antenna and the EBG structure are fabricated on an F4B semi-flexible substrate having a dielectric constant of 2.2. The EBG structure effectively isolates the human body from the radiation of the antenna and reduces the specific absorption rate (SAR) of it by more than 97.5%. This improves the antenna gain and the peak gain reaches 9.1 dBi at 5.8 GHz. The wearable performance of the antenna showed that it can sustain good performance even under realistic human body loading. Besides, the antenna has a small size, which makes it ideal for wearable applications.

Magnetic hyperthermia is a promising technique for the minimally invasive elimination of solid tumors. In this study, uniform magnetite nanoparticles (MNPs) with different particle sizes were used as a model system to investigate the size and surface effects of human-like collagen protein-coated MNPs (HLC-MNPs) on specific absorption rate and biocompatibility. It was found that these HLC-MNPs possess rapid heating capacity upon alternating magnetic field exposure compared to that of MNPs without HLC coating, irrespective of the size of MNPs. The significant enhancement of specific absorption rate is favorable for larger sized nanoparticles. Such behavior is attributed to the reduced aggregation and increased stability of the HLC-MNPs. By coating HLC on the surface of certain sized MNPs, a significant increase in cell viability (up to 2.5-fold) can be achieved. After subcutaneous injection of HLC-MNPs into the back of Kunming mice, it was observed that the inflammatory reaction hardly occurred in the injection site. However, there was a significant presence of phagocytes and endocytosis after the injection of nonconjugated counterparts. The overall strategy to fabricate HLC-MNPs can serve as a general guideline to address the current challenges in clinical magnetic hyperthermia, improved biocompatibility, and enhanced heating characteristics through protein coating.

Wireless technologies have transformed human lifestyles giving rise to research on electromagnetic (EM) field exposure assessment by prioritising what are considered as potentially the more vulnerable groups, such as children. The method presented in this study for assessing the exposure of children to EM fields from wireless communication devices consists of a statistical survey of families describing typical daily exposure to wireless devices followed by the estimation of the highest whole-body averaged specific absorption rate (SAR) between the vertical and horizontal polarisations (SARWBmax) for different devices according to the distance to the user using measured electric field data. Survey outputs, including daily exposure in hours and reported exposure distances, were used to identify spots for in situ experimental evaluation accomplished with a series of measurements of electric field strength of various wireless devices. Complementary to the results of the incident electric field strength, the SARWBmax values for 1–10 years old children during real-life exposure conditions to a few wireless communication devices are presented. The obtained results may contribute to derive recommendations on children exposure limits to specific wireless communication devices for far-field exposure scenarios.

Compact low specific absorption rate (SAR) hexa-band planar inverted-F antenna (PIFA) with independent resonant frequency control is presented in this study. Two trapezoidal shaped slots are etched on the coplanar waveguide (CPW)-fed PIFA-radiating plate to create two independent resonant frequencies as well as the fundamental CPW-fed PIFA itself. Three coupled slots are added within the ground plane to create additional three independent resonant frequencies with slight effect on the other resonant frequencies. Multiband (dual, tri, quad, penta and hexa) band capabilities with bandwidth enhancement and acceptable SAR values are realised for different wireless communication applications. The SAR of human head is investigated by using Computer Simulation Technology (CST) 2012 Microwave Studio Hugo Voxel Model. The proposed antennas are fabricated and there is a good agreement between measured and simulated results.

Early detection of increased infections or new variants of SARS-CoV-2 is critical for public health response. To determine whether cycle threshold (Ct) data from PCR tests for SARS-CoV-2 could serve as an early indicator of epidemic growth, we analyzed daily mean Ct values in England, UK, by gene target and used iterative sequential regression to detect break points in mean Ct values (and positive test counts). To monitor the epidemic in England, we continued those analyses in real time. During September 2020–January 2022, a total of 7,611,153 positive SARS-CoV-2 PCR test results with Ct data were reported. Spike (S) gene target (S+/S−)–specific mean Ct values decreased 6–29 days before positive test counts increased, and S-gene Ct values provided early indication of increasing new variants (Delta and Omicron). Our approach was beneficial in the context of the first waves of the COVID-19 pandemic and can be used to support future infectious disease monitoring.

Teaser: Our review found the average R0 for 2019-nCoV to be 3.28, which exceeds WHO estimates of 1.4 to 2.5.

Dried blood spot (DBS) samples can be used for the detection of severe acute respiratory syndrome coronavirus 2 spike antibodies. DBS sampling is comparable to matched serum samples with a relative 98.1% sensitivity and 100% specificity. Thus, DBS sampling offers an alternative for population-wide serologic testing in the coronavirus pandemic.

The new WHO reference standard allows for the definition of serum antibodies against various SARS-CoV-2 antigens in terms of binding antibody units (BAU/mL) and thus to compare the results of different ELISA systems. In this study, the concentration of antibodies (ABs) against both the S- and the N-protein of SARS-CoV-2 as well as serum neutralization activity were evaluated in three patients after a mild course of COVID-19. Serum samples were collected frequently during a period of over one year. Furthermore, in two individuals, the effects of an additional vaccination with a mRNA vaccine containing the S1-RBD sequence on these antibodies were examined. After natural infection, the antibodies (IgA, IgG) against the S1-protein remained elevated above the established cut-off to positivity (S-IgA 60 BAU/mL and S-IgG 50 BAU/mL, respectively) for over a year in all patients, while this was not the case for ABs against the N-protein (cut-off N-IgG 40 BAU/mL, N-IgA 256 BAU/mL). Sera from all patients retained the ability to neutralize SARS-CoV-2 for more than a year. Vaccination resulted in a rapid boost of antibodies to S1-protein but, as expected, not to the N-protein. Most likely, the wide use of the WHO reference preparation will be very useful in determining the individual immune status of patients after an infection with SARS-CoV-2 or after vaccination.

Although in vitro studies suggest that neutralization by monoclonal antibodies (mAbs) against SARS CoV2 Omicron sub lineages is reduced, in vivo virological response data are lacking. MONET (EudraCT: 2021–004188-28) was multi-centric phase 4 open-label parallel randomized clinical trial, conducted in Italy over 2022–2023, to assess the efficacy of sotrovimab (SOT), tixagevimab/cilgavimab (TIX/CIL) and Nirmatrelvir/ritonavir (NMV/r), in outpatients at high risk for severe COVID-19. The outcome (secondary in the trial protocol) was SARS-CoV-2 variation in cycle threshold (CT) values over the first 7 days (D1-D7) of the trial. CT variation was compared by trial arms using unadjusted linear regression and after controlling for age. We included 346 individuals: 116 (34%) received SOT, 113 (33%) TIX/CIL, 117 (34%) NMV/r. Main characteristics were balanced across arms. Most of the participants were infected with BA.2 (52%) or BA.4/5 (35.5%). The data carried strong evidence that the mean CT change over D1-D7 was larger in subjects receiving NMV/r vs. the other arms (p < 0.001). We found no evidence that viral variant was an effect measure modifier for the contrasts of interest (p = 0.14). Our analysis provides strong evidence that NMV/r exerts a greater in vivo antiviral effect than anti-Spike mAbs against Omicron sub lineages, confirming previous in vitro data.

Background Viral antigen rapid detection tests (Ag-RDTs) and PCR-based nucleic acid amplification tests (NAATs) are essential for diagnosing infections like SARS-CoV-2. However, unlike nucleic acids which can be quantified precisely in copies, viral antigens lack a standardized unit of measurement, hindering precise analytical evaluation of Ag-RDTs and comparison with NAATs. Methods We established a universal national standard for SARS-CoV-2 antigen and nucleic acid based on an Omicron BA.1 strain, inactivated using β-propiolactone (BPL). Its concentration was assigned via multi-laboratory digital PCR (dPCR). Clinical samples were tested with Ag-RDTs and NAATs. We also compared the impact of heat and BPL inactivation on detection using dPCR, qPCR, and sequencing. The standard was then used to evaluate the limits of detection (LoDs) of commercial Ag-RDTs and NAATs using a common unitage. Results Clinical samples’ results showed that antigen positivity was correlated with higher nucleic acid titers. Both BPL inactivation and heat inactivation maintained comparable nucleic acid titers, but BPL inactivation preserved better antigen activity. The national standard concentration was assigned as 1.04 × 10 8 Unit/mL (standard uncertainty: 3.48 × 10 6 Unit/mL). Using this standard, NAATs exhibited lower LoDs than Ag-RDTs, though some Ag-RDT sensitivity approached NAAT levels. Most commercial assays met or exceeded their claimed LoDs, with all claimed NAAT LoDs falling within 2-fold of measured values. The standard enabled direct cross-format LoD comparison. Conclusion We established and validated a BPL-inactivated universal national standard specifically designed to overcome the difficulties in quantifying antigen and enabling direct sensitivity comparison between SARS-CoV-2 Ag-RDTs and NAATs.