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Paslahepevirus balayani (previously known as hepatitis E virus [HEV]; family Hepeviridae) is the leading cause of acute viral hepatitis in humans (2,2). Although 8 different genotypes of HEV have been [...]

Simple Summary: Brucella ceti is a marine bacterium that causes neurological, reproductive and skeletal disease in free-ranging cetaceans. Its zoonotic potential and importance for wild animals has prompted, over the years, the search for a reliable diagnostic method to detect antibodies and infer the level of infection. In this work, we perform an exploratory serological study on cetaceans stranded in the Northwestern Mediterranean Sea. Antibody levels were higher in animals with confirmed Brucella disease and infection in juveniles and in animals with chronic morbilliviral infection. This provides the first seroprevalence estimation in this area and reaffirms the active circulation of Brucella in wild cetaceans. Neurobrucellosis in cetaceans, caused by Brucella ceti, is a relevant cause of death in striped dolphins (Stenella coeruleoalba) from the Mediterranean Sea. Serological tests are not used as a routinary technique for the diagnosis of this infection. We briefly describe the pathological findings of nine free-ranging stranded cetaceans diagnosed with Brucella disease or infection in our veterinary necropsy service from 2012 to 2022. The findings included focal diskospondylitis and non-suppurative meningitis, choroiditis and radiculitis. Additionally, an exploratory serological study was conducted in sixty-six frozen sera collected in the period 2012–2022 from fifty-seven striped dolphins, five Risso's dolphins (Grampus griseus), two common bottlenose dolphins (Tursiops truncatus), one common dolphin (Delphinus delphis) and one pilot whale (Globicephala melas) to compare antibody levels in Brucella-infected (n = 8) and non-infected (n = 58) animals, classified by the cause of death, sex, age class and cetacean morbillivirus (CeMV) infection status. The authors hypothesized that active infection in cases of neurobrucellosis would elicit a stronger, detectable humoral response compared to subclinical infections. We performed a commercial competition ELISA (cELISA) using serial serum dilutions for each sample, considering a percentage of inhibition (PI) of ≥40% as positive. A titer of 1:160 was arbitrarily determined as the seropositivity threshold. Seropositive species included striped dolphins and Risso's dolphins. Seroprevalence was higher in animals with neurobrucellosis (87.5%) compared to the overall seroprevalence (31.8%) and to other causes of death, indicating, likely, a high sensitivity but low specificity for neurobrucellosis. Animals with chronic CeMV seemed to have higher seroprevalences, as well as juveniles, which also had a higher disease prevalence. These results indicate, as in other studies, that antibodies are not decisive against clinical brucellosis, although they may indicate a carrier state, and that CeMV may influence Brucella epidemiology. More research is required to elucidate the epidemiology and pathogenesis and to resolve the complicated host–pathogen interaction in Brucella species. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), considered a zoonotic agent of wildlife origin, can infect various animal species, including wildlife in free-range and captive environments. Detecting susceptible species and potential reservoirs is crucial for preventing the transmission, spread, genetic evolution, and further emergence of viral variants that are major threats to global health. This study aimed to detect exposure or acute infection by SARS-CoV-2 in 420 animals from 40 different wildlife species, including terrestrial and aquatic mammals, from different regions of Spain during the 2020–2023 coronavirus disease 19 (COVID-19) pandemic. In total, 8/137 animals were positive for SARS-CoV-2 antibodies against the receptor binding domain and/or viral nucleoprotein according to independent ELISAs. However, only one ELISA-positive sample of a captive bottlenose dolphin (Tursiops truncatus) tested positive for SARS-CoV-2 neutralizing antibodies with a low titre (SNT50 38.15) according to a virus neutralization test. Cetaceans are expected to have a high risk of infection with SARS-CoV-2 according to early predictive studies due to the similarity of their angiotensin converting enzyme 2 cell receptor to that of humans. Moreover, of 283 animals analysed for SARS-CoV-2 RNA using RT-qPCR, none tested positive. Our results reinforce the importance of considering cetaceans at risk for SARS-CoV-2 infection and support taking preventive biosecurity measures when interacting with them, especially in the presence of individuals with suspected or confirmed COVID-19. Although most animals in this study tested negative for acute infection or viral exposure, ongoing surveillance of wildlife species and potentially susceptible animals is important to prevent future spillover events and detect potential novel reservoirs. [ABSTRACT FROM AUTHOR]

The reactions of 2-naphthylamine and methyl 6-amino-2-naphthoate with formalin and paraformaldehyde were studied experimentally, spectrally, and by quantum chemical calculations. It was found that neither the corresponding aminals nor imines were formed under the described conditions but could be prepared and spectrally characterized at least in situ under modified conditions. Several of the previously undescribed intermediates and by-products were isolated or at least spectrally characterized. First principle density functional theory (DFT) calculations were performed to shed light on the key aspects of the thermochemistry of decomposition and further condensation of the corresponding aminals and imines. The calculations also revealed that the electrophilicity of methanal was significantly greater than that of ordinary oxo-compounds, except for perfluorinated ones. In summary, methanal was not behaving as the simplest aldehyde but as a very electron-deficient oxo-compound.

Practical research experience has been seen as an important tool to enhance learning in STEM fields and shape commitment to science careers. Indeed, this was a prominent recommendation of the Boyer Commission. Further, there is evidence this is especially important for minority students. In this paper, we examine the role of practical research experience during the summer for talented minority undergraduates in STEM fields. We focus on the link between summer research and STEM Ph.D. program matriculation. We examine evidence on this question using detailed data on students participating in the Meyerhoff Scholarship Program over a 14 year period at the University of Maryland Baltimore County. Our results provide evidence of strong positive effects of summer research on participation in STEM Ph.D. programs. Further, we show that the effects of summer research vary with the frequency and timing of these experiences. The evidence that educational strategies such as summer research experiences improve academic outcomes of minorities is vital, given concern about the science pipeline in the U.S. and the continuing growth in the racial/ethnic diversity of the college-age population. (Contains 7 tables, 2 figures and 13 footnotes.)

The main etiologic agent of tuberculosis (TB) in livestock and wildlife is Mycobacterium bovis. This species also infects humans through inhalation or ingestion and causes TB that is clinically indistinguishable [...]

Previous research has shown that the Meyerhoff Scholars Program at the University of Maryland, Baltimore County, is an effective intervention for high-achieving underrepresented minority (URM) students; African-American Meyerhoff students are significantly more likely to enter science, technology, engineering, and mathematics (STEM) PhD programs than comparison students. The first of two studies in this report extends the prior research by examining levels of PhD completion for Meyerhoff (N = 479) versus comparison sample (N = 249) students among the first 16 cohorts. Entering African-American Meyerhoff students were 4.8 times more likely to complete STEM PhDs than comparison sample students. To enhance understanding of potential mechanisms of influence, the second study used data from the 22nd (Fall 2010) to 25th (Fall 2013) cohorts (N = 109) to test the hypothesis that perceived program benefit at the end of freshman year would mediate the relationship between sense of community at the end of Summer Bridge and science identity and research self-efficacy at the end of sophomore year. Study 2 results indicated that perceived program benefit fully mediated the relationship between sense of community and both criterion measures. The findings underscore the potential of comprehensive STEM intervention programs to enhance PhD completion, and suggest mechanisms of influence.

The Meyerhoff Scholarship Program (MSP) is widely recognized for its comprehensive approach of integrating students into the science community. The supports provided by the program aim to develop students, primarily Blacks, into scientists by offering them academic, social, and professional opportunities to achieve their academic and career goals. The current study allowed for a rich understanding of the perceptions of current Meyerhoff students and Meyerhoff alumni about how the program works. Three groups of MSP students were included in the study: (1) new Meyerhoff students participating in Summer Bridge (n = 45), (2) currently enrolled Meyerhoff students (n = 92), and (3) graduates of the MSP who were currently enrolled in STEM graduate studies or had completed an advanced STEM degree (n = 19). Students described the importance of several key aspects of the MSP: financial support, the Summer Bridge Program, formation of Meyerhoff identity, belonging to the Meyerhoff family, and developing networks--all of which serve to integrate students both academically and socially.