39 research outputs found

    Investigation of the Impact of Mycogenic Titanium and Selenium Nanoparticles on Fusarium Wilt Infection of Tomato Plant

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    We applied biosynthesized titanium and selenium nanoparticles, prepared using a fungal water extract of Trichoderma harzianum (T. harzianum), to eradicate tomota wilt infection. Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Energy Dispersive X-Ray analysis, and Transmission electron microscopy/X-ray diffraction (TEM/XRD) techniques were used to characterize the spherical metal nanoparticles, whose diameters were 16.0 nm for selenium nanoparticles (SeNPs) and 50.0 nm for titanium nanoparticles (TiNPs). This confirmed the efficient biosynthesis of the nanoparticles. Under greenhouse conditions, the effectiveness of TiNPs and SeNPs produced by nonpathogenic fungi (T. harzianum) against the pathogen responsible for the tomato wilt disease, Fusarium oxysporum (F. oxysporum), was studied. Based on the results, the most efficient method for combating the pathogen that causes tomato wilt was used in open fields, whereas pot studies were conducted in greenhouse conditions. All tested treatments considerably lowered tomato plant wilt disease in both the greenhouse and the open field. The disease severity was reduced by 20.4% using TiNPs at high concentrations of 150 ppm and by 41.5% using SeNPs. Compared to conventional antibiotics, the antibacterial activity assessment of the biosynthesized TiNPs and SeNPs revealed a significant effect versus pathogenic bacteria and fungi, with a negligible influence on the examined human and animal microflora. The findings showed that biosynthesized TiNPs and SeNPs can be applied to suppress the plant pathogen F. oxysporum in a way that is safe for the microflora of humans and animals. This is the first instance where the nanocidal activity of biological TiNPs and SeNPs has been used against the pathogen that causes tomato wilt

    Lives versus Livelihoods? Perceived economic risk has a stronger association with support for COVID-19 preventive measures than perceived health risk

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    This paper examines whether compliance with COVID-19 mitigation measures is motivated by wanting to save lives or save the economy (or both), and which implications this carries to fight the pandemic. National representative samples were collected from 24 countries (N = 25,435). The main predictors were (1) perceived risk to contract coronavirus, (2) perceived risk to suffer economic losses due to coronavirus, and (3) their interaction effect. Individual and country-level variables were added as covariates in multilevel regression models. We examined compliance with various preventive health behaviors and support for strict containment policies. Results show that perceived economic risk consistently predicted mitigation behavior and policy support—and its effects were positive. Perceived health risk had mixed effects. Only two significant interactions between health and economic risk were identified—both positive

    Body appreciation around the world: Measurement invariance of the Body Appreciation Scale-2 (BAS-2) across 65 nations, 40 languages, gender identities, and age.

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    The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research. [Abstract copyright: Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.

    Identifying important individual‐ and country‐level predictors of conspiracy theorizing: a machine learning analysis

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    Psychological research on the predictors of conspiracy theorizing—explaining important social and political events or circumstances as secret plots by malevolent groups—has flourished in recent years. However, research has typically examined only a small number of predictors in one, or a small number of, national contexts. Such approaches make it difficult to examine the relative importance of predictors, and risk overlooking some potentially relevant variables altogether. To overcome this limitation, the present study used machine learning to rank-order the importance of 115 individual- and country-level variables in predicting conspiracy theorizing. Data were collected from 56,072 respondents across 28 countries during the early weeks of the COVID-19 pandemic. Echoing previous findings, important predictors at the individual level included societal discontent, paranoia, and personal struggle. Contrary to prior research, important country-level predictors included indicators of political stability and effective government COVID response, which suggests that conspiracy theorizing may thrive in relatively well-functioning democracies

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Use molecular techniques as an alternative tool for diagnosis and characterization of Theileria equi

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    The purpose of this study was to determine the prevalence of clinical, subclinical and chronic infection with the equine parasite T. equi in some Egyptian localities (Cairo and Giza governorates). A panel of 396 equine blood samples representing 141 horses, 250 donkeys and 5 mules was collected from equines during the period from April 2015 to March 2016 using microscopic examination and conventional PCR. Microscopically a twenty two (5.56%) of 396 were positive for T. equi merozoites that appeared as small rounded, pyriform shaped and maltase cross shaped merozoites. Among 8/141(5.67%) horses and 14/250 (5.60%) donkeys were found to have positive for T.equi. A one hundred blood samples (45 horses, 50 donkeys and 5 mules) selected randomly were also examined by PCR. The results of PCR showed 30/100(11/45 (24.4%) horses, 18/50 (36%) donkeys and 1/5 (20%) mule) were positive for T.equi. When the sequenced PCR amplicons (n=3) were aligned to the reference nucleotide sequences of T. equi accessed in Genbank, the horse isolate showed insertion of Thymine (T) base at position 23 and substitution of Thymine (T) base with Cytosine (C) base at position 91, while the donkey and mule isolates have no alterations when compared to the reference sequences. The phylogenetic analysis showed that the sequenced PCR isolates belonged to T. equi. The obtained sequences were deposited in the GeneBank database under accession numbers MF192854, MF192855 and MF192856
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