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Abstract: Using families of irreducible Hilbert space representations as a tool, the theory of analytic Fredholm operator valued function is extended to a -algebra setting. This includes a -algebra version of Rouché’s Theorem known from complex function theory. Also, criteria for spectral regularity of -algebras are developed. One of those, involving the (generalized) Calkin algebra, is applied to -algebras generated by a non-unitary isometry. [Copyright &y& Elsevier]

Abstract: In this paper we discuss the asymptotic distribution of the approximation numbers of the finite sections for a Toeplitz operator , , where a is a piecewise continuous function on the unit circle. We prove that the behavior of the approximation numbers of the finite sections depends heavily on the Fredholm properties of the operators and . In particular, if the operators and are Fredholm on , then the approximation numbers of have the so-called k-splitting property. But, in contrast with the case of continuous symbols, the splitting number k is in general larger than . [Copyright &y& Elsevier]

The COVID-19 pandemic influenced emotional experiences globally. We examined daily positive and negative affect between May/June 2020 and February 2021 (N = 151,049; 3,509,982 observations) using a convenience sample from a national mobile application-based survey that asked for daily affect reports. Four questions were examined: (1) How did people in the United States feel from May/June 2020 to February 2021?; (2) What demographic variables are related to positive and negative affect?; (3) What is the relationship between experienced stressors and daily affect?; and (4) What is the relationship between daily affect and preventive behavior? Positive affect increased, and negative decreased over time. Demographic differences mirrored those from before the pandemic (e.g., younger participants reported more negative and less positive affect). Stressors such as feeling unwell, experiencing COVID-19 symptoms, exposure to COVID-19, and lack of sleep were associated with less positive and more negative affect. Exercising protective behaviors predicted future affect, and affect also predicted future protective behaviors (e.g., less protective behavior when happy but more when grateful and thoughtful). The implications for public health communication were discussed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ivcevic, Shen, Lin, Cheng, Probasco, Silbermann, Zhang, Lin and Brackett.)

SARS-CoV-2 vaccines are useful tools to combat the Coronavirus Disease 2019 (COVID-19) pandemic, but vaccine reluctance threatens these vaccines' effectiveness. To address COVID-19 vaccine reluctance and ensure equitable distribution, understanding the extent of and factors associated with vaccine acceptance and uptake is critical. We report the results of a large nationwide study in the US conducted December 2020-May 2021 of 36,711 users from COVID-19-focused smartphone-based app How We Feel on their willingness to receive a COVID-19 vaccine. We identified sociodemographic and behavioral factors that were associated with COVID-19 vaccine acceptance and uptake, and we found several vulnerable groups at increased risk of COVID-19 burden, morbidity, and mortality were more likely to be reluctant to accept a vaccine and had lower rates of vaccination. Our findings highlight specific populations in which targeted efforts to develop education and outreach programs are needed to overcome poor vaccine acceptance and improve equitable access, diversity, and inclusion in the national response to COVID-19., (© 2023. The Author(s).)

Background: The ANRS COV1-COHVAC cohort was a long-term safety cohort of healthy volunteers who received preventive HIV-vaccine candidates in 17 phase I/II clinical trials., Methods: Data collected from the first vaccine candidate administration and annually after inclusion in the cohort included grade 3/4 adverse events and all grade adverse events suggestive of neurological, ophthalmological and immune disorders, self-administered questionnaires on behaviors and HIV ELISA results. Age-and-sex-standardized mortality ratios (SMRs) were calculated with respect to the French population. The cohort was early terminated in 2016 due to the absence of safety signal., Results: Of 496 volunteers, 488 were included: 355 in the 7-year prospective follow-up and 133 in the retrospective data collection only. The total follow-up after the first vaccination was 4934 person-years (median: 10 years) and 270 (76%) volunteers completed their follow-up. No relevant adverse event possibly related to the vaccine was reported. Breast cancer incidence and woman mortality did not differ from those of the French general population (standardized incidence ratio = 1.47, P = 0.45 and SMR = 0.65, P = 0.28, respectively) while man mortality was significantly lower (SMR = 0.26, P = 0.0003). At the last visit, 21/29 (72%) volunteers who received the recombinant HIV gp160 protein still showed vaccine-induced seropositivity after a median follow-up of 23 years. Only a few volunteers reported risky sexual practices (men: 20/192, women: 2/162)., Conclusion: Volunteers showed a sustained high commitment. No long-term safety alert was identified during the postvaccine follow-up. Participating in vaccine trials did not increase risky behaviors for HIV infection. Vaccine-induced seropositivity may persist for more than 23 years after receiving rgp160.

Background: In low hepatitis B virus (HBV)-prevalent countries, most HBV-infected persons are unaware of their status. We aimed to evaluate whether (i) previous HBV-testing, (ii) physicians decision to screen, and (iii) CDC's recommendations identified infected individuals and which risk-factor groups needing testing., Methods: During a mass, multi-center HBV-screening study from September 2010-August 2011, 3929 participants were screened for hepatitis B surface antigen (HBsAg), anti-HBs and anti-Hepatitis B core antibodies (anti-HBcAb). Questions on HBV risk-factors and testing practices were asked to participants, while participants' eligibility for HBV-testing was asked to study medical professionals., Results: 85 (2.2%) participants were HBsAg-positive, while 659 (16.8%) had either resolved HBV infection or isolated anti-HBcAb. When comparing practices, HBV-testing was more likely to occur in HBV-infected participants if Centers for Disease Control and Prevention (CDC) recommendations were used (Sensitivity = 100%, 95%CI: 95.8-100) than physicians' discretion (Sensitivity = 87.1%, 95%CI: 78.0-93.4) or previous HBV-test (Sensitivity = 36.5%, 95%CI: 26.3-47.6) (p<0.0001). Nevertheless, many non-infected individuals would still have been screened using CDC-recommendations (Specificity = 31.1%, 95%CI: 29.6-32.6). Using multivariable logistic regression, HBsAg-positive status was significantly associated with the following: males, originating from high HBV-endemic region, contact with HBV-infected individual, without national healthcare, and intravenous-drug user (IDU). Of these risk-factors, physician's discretion for testing HBV was not significantly associated with participants' geographical origin or IDU., Conclusions: Missed opportunities of HBV-screening are largely due to underestimating country of origin as a risk-factor. Applying CDC-recommendations could improve HBV-screening, but with the disadvantage of many tests. Further development of HBV-testing strategies is necessary, especially before severe disease occurs.

Objective: The objective was to compare the safety and cellular immunogenicity of intradermal versus intramuscular immunization with an HIV-lipopeptide candidate vaccine (LIPO-4) in healthy volunteers., Methodology: A randomized, open-label trial with 24 weeks of follow-up was conducted in France at six HIV-vaccine trial sites. Sixty-eight healthy 21- to 55-year-old HIV-uninfected subjects were randomized to receive the LIPO-4 vaccine (four HIV lipopeptides linked to a T-helper-stimulating epitope of tetanus-toxin protein) at weeks 0, 4 and 12, either intradermally (0.1 ml, 100 microg of each peptide) or intramuscularly (0.5 ml, 500 microg of each peptide). Comparative safety of both routes was evaluated. CD8+ T-cell immune responses to HIV epitopes (ELISpot interferon-gamma assay) and tetanus toxin-specific CD4+ T-cell responses (lymphoproliferation) were assessed at baseline, two weeks after each injection, and at week 24., Results and Conclusion: No severe, serious or life-threatening adverse events were observed. Local pain was significantly more frequent after intramuscular injection, but local inflammatory reactions were more frequent after intradermal immunization. At weeks 2, 6, 14 and 24, the respective cumulative percentages of induced CD8+ T-cell responses to at least one HIV peptide were 9, 33, 39 and 52 (intradermal group) or 14, 20, 26 and 37 (intramuscular group), and induced tetanus toxin-specific CD4+ T-cell responses were 6, 27, 33 and 39 (intradermal), or 9, 46, 54 and 63 (intramuscular). In conclusion, intradermal LIPO-4 immunization was well tolerated, required one-fifth of the intramuscular dose, and induced similar HIV-specific CD8+ T-cell responses. Moreover, the immunization route influenced which antigen-specific T-cells (CD4+ or CD8+) were induced., Trial Registration: ClinicalTrials.gov NCT00121121.

Two new vaccines have been recently licensed : a quadrivalent vaccine against Human papillomavirus infections (HPV) 6, 11, 16 and 18, recommended to children from 9 years old and to young adults under the age of 26 years, and a vaccine against herpes zoster for adults from 60 years old onwards. A bivalent vaccine against HPV 16 and 18 will be shortly available. HPV vaccines are composed of the L1 structural proteins of 2 or 4 HPV genotypes, produced by genetic engineering and self-assembled. These inert vaccines are devoid of genetic materials and mimic the viral particle (virus-like particle, VLP). They allow, as suggested by the 4.5 to 5 years follow-up, to prevent HPV infections and the onset of pre-cancerous lesions associated with genotypes contained within the vaccine. They represent a major overhang in the vaccinology field, and, as anti-hepatitis B vaccine, will probably be effective in cancer prevention. Their use must be associated with the continued detection of cervix cancer by smears and also with the prevention of other sexually transmitted diseases. The herpes zoster vaccine is a living attenuated vaccine produced from the OKA/Merck strain already used in the vaccine against varicella. Its safety is good among persons 50 years old and over and its efficiency on lowering herpes zoster incidence, on the burden of illness and on post-herpetic neuralgia has been demonstrated in persons over 60 years old.