To Achieve Security and High Spectrum Efficiency: A New Transmission System Based on Faster-than-Nyquist and Deep Learning

With the rapid development of various services in wireless communications, spectrum resource has become increasingly valuable. Faster-than-Nyquist (FTN) signaling, which was proposed in the 1970s, has been a promising paradigm to improve the spectrum utilization. In this paper, we try to apply FTN into secure communications and propose a secure and high-spectrum-efficiency transmission system based on FTN and deep learning (DL). In the proposed system, the hopping symbol packing ratio with random values makes it difficult for the eavesdropper to obtain the accurate symbol rate and inter-symbol interference (ISI). While the receiver can use the blind estimation to choose the true parameters with the aid of DL. The results show that without the accurate symbol packing ratio, the eavesdropper will suffer from severe performance degradation. As a result, the system can achieve a secure transmission with a higher spectrum efficiency. Also, we propose a simplified symbol packing ratio estimation which has bee employed in our proposed system. Results show that the proposed simplified estimation achieves nearly the same performance as the original structure while its complexity has been greatly reduced

Biometric measurements in highly myopic eyes

Purpose: To assess the repeatability and accuracy of optical biometry (Lenstar LS900 optical low-coherence reflectometry [OLCR] and IOLMaster partial coherence interferometry [PCI]) and applanation ultrasound biometry in highly myopic eyes. Setting: Division of Preventive Ophthalmology, Zhongshan Ophthalmic Center, Guangzhou, China. Design: Comparative evaluation of diagnostic technology. Methods: Biometric measurements were taken in highly myopic subjects with a spherical equivalent (SE) of -6.00 diopters (D) or higher and an axial length (AL) longer than 25.0 mm. Measurements of AL and anterior chamber depth (ACD) obtained by OLCR were compared with those obtained by PCI and applanation A-scan ultrasound. Right eyes were analyzed. Repeatability was evaluated using the coefficient of variation (CoV) and agreement, using Bland-Altman analyses. Results: The mean SE was -11.20 D ± 4.65 (SD). The CoVs for repeated AL measurements using OLCR, PCI, and applanation ultrasound were 0.06%, 0.07%, and 0.20%, respectively. The limits of agreement (LoA) for AL were 0.11 mm between OLCR and PCI, 1.01 mm between OLCR and applanation ultrasound, and 1.03 mm between PCI and ultrasound. The ACD values were 0.29 mm, 0.53 mm, and 0.51 mm, respectively. These repeatability and agreement results were comparable in eyes with extreme myopia (AL ≥27.0 mm) or posterior staphyloma. The mean radius of corneal curvature was similar between OLCR and PCI (7.66 ± 0.24 mm versus 7.64 ± 0.25 mm), with an LoA of 0.12 mm. Conclusion: Optical biometry provided more repeatable and precise measurements of biometric parameters, including AL and ACD, than applanation ultrasound biometry in highly myopic eyes. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned

Geosocial Networking Smartphone App Use and High-Risk Sexual Behaviors Among Men Who Have Sex With Men Attending University in China: Cross-sectional Study

BackgroundGay apps are smartphone-based geosocial networking apps where many men who have sex with men (MSM) socialize and seek sex partners. Existing studies showed that gay app use is associated with greater odds of high-risk sexual behaviors and potentially more HIV infections. However, little is known about this behavior among young MSM. ObjectiveWe conducted this study to understand gay app use and its influencing factors among MSM attending university in China. MethodsFrom January to March 2019, participants were recruited from 4 regions with large populations of college students in China: Chongqing, Guangdong, Shandong, and Tianjin. The eligibility criteria were MSM aged 16 years or older, self-identified as a university student, and being HIV negative. A self-administered online structured questionnaire was used to collect data on sociodemographic information, sexual behaviors, gay app use, substance use, and HIV testing history. We performed multivariable log-binomial regression to assess correlates of seeking sex partners via gay apps. ResultsA total of 447 MSM attending university with an average age of 20.4 (SD 1.5) years were recruited. Almost all participants (439/447, 98.2%) reported gay app use at some point in their life, and 240/439 (53.7%) reported ever seeking sex partners via gay apps. Blued (428/439, 97.5%) was the most popular gay app. Higher proportions of sexual risk behaviors (including seeking sex partners via apps [P<.001], engaging in group sex [P<.001], having multiple sex partners [P<.001], unawareness of sex partners’ HIV status [P<.001], and using recreational drugs during sex [P<.02]) were positively associated with the increase in the frequency of gay app use. In multivariable analysis, participants who used gay apps to seek sex partners might be more likely to have multiple sex partners in the past 3 months (adjusted prevalence ratio [APR] 1.53, 95% CI 1.33-1.76; P<.001), engage in group sex in the past 3 months (APR 1.55, 95% CI 1.35-1.78; P<.001), and have sex partners with unknown or positive HIV status (APR 1.72, 95% CI 1.46-2.01; P<.001). ConclusionsSeeking sex partners via gay apps may associate with the increased high-risk sexual behaviors among MSM attending university. The causality between seeking sex partners via gay apps and increased high-risk sexual behaviors should be further investigated so as to inform potential policies for HIV prevention. Trial RegistrationChinese Clinical Trial Registry ChiCTR1900020645; http://www.chictr.org.cn/showprojen.aspx?proj=3474

Development of a Gold Nanoparticle-Based Immunochromatographic Strip for Rapid Detection of Porcine Circovirus Type 2

ABSTRACT Porcine circovirus type 2 (PCV2) is an important swine infectious pathogen that seriously threatens the global swine industry. PCV2 Cap protein is the only structural and the main immunogenic protein constituting the viral capsid. In this study, a gold nanoparticle-based immunochromatographic strip with high sensitivity and specificity was developed which could be used for rapid detection of PCV2 virions or Cap protein in research. The visual detection limit of the strip was 103.18 50% tissue culture infective does (TCID50)/mL for PCV2, and 2.03 μg/mL for PCV2 Cap protein. No cross-reactivity was observed with the PCV1 and PCV3 Cap proteins and other common swine pathogens such as porcine reproductive and respiratory syndrome virus, classical swine fever virus, pseudorabies virus, porcine epidemic diarrhea virus, porcine parvovirus, and swine influenza virus. The repeatability of the strip was good. The stability of the strip was perfect for 12 months in a dry state at room temperature. Visual results could be obtained within 5 min by simply inserting the strip into the diluted sample. The strip is a time-saving, labor-saving, and reliable tool for testing of PCV2 virions or Cap protein in research. The idea of this study might open a new perspective for the application of the strip. IMPORTANCE Porcine circovirus type 2 (PCV2) Cap protein is the only structural and the main immunogenic protein constituting the viral capsid. Although many methods can be used to identify PCV2 or PCV2 Cap protein in vaccine research, they usually require high workload and time. The developed strip can specifically detect PCV2 virions or Cap protein, and visual qualitative results can be obtained within 5 min by simply diluting the sample and inserting the strip into the sample. The final value of the strip is providing a simple and time-saving method for real-time monitoring of PCV2 antigen in vaccine research with reliable results, such as the different stages of PCV2 Cap protein expression and purification, as well as the different stages of PCV2 reproduction and purification

Double-layered N-S1 protein nanoparticle immunization elicits robust cellular immune and broad antibody responses against SARS-CoV-2

Abstract Background The COVID-19 pandemic is a persistent global threat to public health. As for the emerging variants of SARS-CoV-2, it is necessary to develop vaccines that can induce broader immune responses, particularly vaccines with weak cellular immunity. Methods In this study, we generated a double-layered N-S1 protein nanoparticle (N-S1 PNp) that was formed by desolvating N protein into a protein nanoparticle as the core and crosslinking S1 protein onto the core surface against SARS-CoV-2. Results Vaccination with N-S1 PNp elicited robust humoral and vigorous cellular immune responses specific to SARS-CoV-2 in mice. Compared to soluble protein groups, the N-S1 PNp induced a higher level of humoral response, as evidenced by the ability of S1-specific antibodies to block hACE2 receptor binding and neutralize pseudovirus. Critically, N-S1 PNp induced Th1-biased, long-lasting, and cross-neutralizing antibodies, which neutralized the variants of SARS-CoV-2 with minimal loss of activity. N-S1 PNp induced strong responses of CD4+ and CD8+ T cells, mDCs, Tfh cells, and GCs B cells in spleens. Conclusions These results demonstrate that N-S1 PNp vaccination is a practical approach for promoting protection, which has the potential to counteract the waning immune responses against SARS-CoV-2 variants and confer broad efficacy against future new variants. This study provides a new idea for the design of next-generation SARS-CoV-2 vaccines based on the B and T cells response coordination. Graphical Abstract Steps involved in the preparation of double-layered N-S1 protein nanoparticle vaccines and experimental design performed in combating virus infection. After intramuscular immunization of mice, the double-layered N-S1 protein nanovaccine could effectively promote the maturation of antigen-presenting and mature dendritic cells, robust broad-spectrum neutralizing antibody production, cytokines secretion, robust mDC, Tfh cell, and GCs B cell responses induction, T-cell memory formation and durable antibody responses, and unique global transcriptome characteristics, thus achieving a robust cellular immunity and broad antibody responses against SARS-CoV-2 based on the B and T cells response coordinatio

A Universal Fluorescent Immunochromatography Assay Based on Quantum Dot Nanoparticles for the Rapid Detection of Specific Antibodies against SARS-CoV-2 Nucleocapsid Protein

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the pathogenic agent leading to COVID-19. Due to high speed of transmission and mutation rates, universal diagnosis and appropriate prevention are still urgently needed. The nucleocapsid protein of SARS-CoV-2 is considered more conserved than spike proteins and is abundant during the virus&rsquo; life cycle, making it suitable for diagnostic applications. Here, we designed and developed a fluorescent immunochromatography assay (FICA) for the rapid detection of SARS-CoV-2-specific antibodies using ZnCdSe/ZnS QDs-conjugated nucleocapsid (N) proteins as probes. The nucleocapsid protein was expressed in E.coli and purified via Ni-NTA affinity chromatography with considerable concentration (0.762 mg/mL) and a purity of more than 90%, which could bind to specific antibodies and the complex could be captured by Staphylococcal protein A (SPA) with fluorescence displayed. After the optimization of coupling and detecting conditions, the limit of detection was determined to be 1:1.024 &times; 105 with an IgG concentration of 48.84 ng/mL with good specificity shown to antibodies against other zoonotic coronaviruses and respiratory infection-related viruses (n = 5). The universal fluorescent immunochromatography assay simplified operation processes in one step, which could be used for the point of care detection of SARS-CoV-2-specific antibodies. Moreover, it was also considered as an efficient tool for the serological screening of potential susceptible animals and for monitoring the expansion of virus host ranges

Air Pollution and Allergic Rhinitis: Findings from a Prospective Cohort Study

To investigate the association of long-term exposure to ambient air pollution with the risk of allergic rhinitis (AR), we performed a longitudinal analysis of 379,488 participants (47.4% women) free of AR at baseline in the UK Biobank. The annual average concentrations of PM2.5, PMcoarse, PM10, NO2, and NOx were estimated by land use regression models. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). A weighted polygenic risk score was constructed. During a median follow-up period of 12.5 years, 3095 AR cases were identified. We observed significant associations between the risk of AR and PM2.5 (HR: 1.51, 95% CI: 1.27–1.79, per 5 μg/m3), PMcoarse (HR: 1.28, 95% CI: 1.06–1.55, per 5 μg/m3), PM10 (HR: 1.45, 95% CI: 1.20–1.74, per 10 μg/m3), NO2 (HR: 1.14, 95% CI: 1.09–1.19, per 10 μg/m3), and NOx (HR: 1.10, 95% CI: 1.05–1.15, per 20 μg/m3). Moreover, participants with high air pollution combined with high genetic risk showed the highest risk of AR, although no multiplicative or additive interaction was observed. In conclusion, long-term exposure to air pollutants was associated with an elevated risk of AR, particularly in high-genetic-risk populations, emphasizing the urgent need to improve air quality