665 research outputs found

    Gender Differentials and Adoption of Drought Tolerant Maize Varieties among Farmers in Northern Nigeria

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    This study examined gender differences in farmer’s adoption of drought tolerant maize (DTM) varieties in Northern Nigeria. Specifically, it described the socio-economic characteristics of the farmers by gender; determined their rate of adoption of the DTM varieties; and analysed the factors affecting the rate of adoption of the varieties. The study was conducted in seven: Borno, Bauchi, Kano, Kaduna, Niger, Zamfara, and Kwara states of Nigeria. A multistage sampling procedure was used to select 946 respondents, comprising 626 males and 320 females. Data were collected with the use of a survey questionnaire that contained questions on respondent’s socio- economic characteristics such as age, years of schooling, household size, farm size, access to credit, level of awareness and adoption of DTM varieties and extension contact, among others. Data were analyzed using descriptive statistics and probit regression model. The results for the entire respondents showed average values of 46 years for age, seven years for year of schooling, 11 for household size, 6.93 for farm size and 5.7 ha for land area allocated to maize, with a significant difference (p<0.05) between male and female farmers for each of the variables. The adoption rate of DTM was 56.3% on the average in the entire sample with a significant difference (p<0.05) between male (61.8%) and female farmers (53.5%). The determinants of adoption of DTM varieties for both male and female farmers were access to credit, participation in field days, household size, fertilizer application, source of seeds and level of awareness of the variety, specific to male farmers was land area allocated to maize and number of livestock while source of information about the DTM variety was specific to female famers. It was concluded that policy strategies aimed at improving the uptake of DTM varieties must consider equality in male and female farmers’ access to basic resources, such as credit, land, labour, and participation in different meetings. Keywords: Gender, Drought tolerant, Maize varieties, Adoption, Nigeria.

    Human and murine IFIT1 proteins do not restrict infection of negative-sense RNA viruses of the Orthomyxoviridae, Bunyaviridae, and Filoviridae families

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    UNLABELLED: Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) is a host protein with reported cell-intrinsic antiviral activity against several RNA viruses. The proposed basis for the activity against negative-sense RNA viruses is the binding to exposed 5\u27-triphosphates (5\u27-ppp) on the genome of viral RNA. However, recent studies reported relatively low binding affinities of IFIT1 for 5\u27-ppp RNA, suggesting that IFIT1 may not interact efficiently with this moiety under physiological conditions. To evaluate the ability of IFIT1 to have an impact on negative-sense RNA viruses, we infected Ifit1(-/-) and wild-type control mice and primary cells with four negative-sense RNA viruses (influenza A virus [IAV], La Crosse virus [LACV], Oropouche virus [OROV], and Ebola virus) corresponding to three distinct families. Unexpectedly, a lack of Ifit1 gene expression did not result in increased infection by any of these viruses in cell culture. Analogously, morbidity, mortality, and viral burdens in tissues were identical between Ifit1(-/-) and control mice after infection with IAV, LACV, or OROV. Finally, deletion of the human IFIT1 protein in A549 cells did not affect IAV replication or infection, and reciprocally, ectopic expression of IFIT1 in HEK293T cells did not inhibit IAV infection. To explain the lack of antiviral activity against IAV, we measured the binding affinity of IFIT1 for RNA oligonucleotides resembling the 5\u27 ends of IAV gene segments. The affinity for 5\u27-ppp RNA was approximately 10-fold lower than that for non-2\u27-O-methylated (cap 0) RNA oligonucleotides. Based on this analysis, we conclude that IFIT1 is not a dominant restriction factor against negative-sense RNA viruses. IMPORTANCE: Negative-sense RNA viruses, including influenza virus and Ebola virus, have been responsible for some of the most deadly outbreaks in recent history. The host interferon response and induction of antiviral genes contribute to the control of infections by these viruses. IFIT1 is highly induced after virus infection and reportedly has antiviral activity against several RNA and DNA viruses. However, its role in restricting infection by negative-sense RNA viruses remains unclear. In this study, we evaluated the ability of IFIT1 to inhibit negative-sense RNA virus replication and pathogenesis both in vitro and in vivo. Detailed cell culture and animal studies demonstrated that IFIT1 is not a dominant restriction factor against three different families of negative-sense RNA viruses

    Gender Differentials in the Adoption of Drought-Tolerant Maize Varieties among Farmers in the Northern Region of Ghana

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    This study examined gender differences in farmers’ adoption of drought-tolerant maize (DTM) varieties in northern region of Ghana. Specifically, it described the socio-economic characteristics of the farmers by gender; determined their rate of adoption of the DTM varieties; and analyzed the factors affecting the rate of adoption of the varieties. The study was conducted in the Northern region of Ghana. Simple random sampling technique was used to obtain data from 600 respondents, comprising 551 males and 49 females. Data were collected with the use of a survey questionnaire that contained questions on respondents’ socio-economic characteristics such as age, years of schooling, household size, farm size, access to credit, level of awareness and adoption of DTM varieties and extension contact, among others. Data were analyzed using descriptive statistics and probit regression model. The results for the entire respondents showed average values of 49.75 years for age, 10.8 for household size, with a significant difference (p<0.05) between male and female farmers for each of the variables. Average farm size of 3.38 ha, with a significant difference (p<0.01) between male and female farmers for the variables. The adoption rate of DTM was 13.3% in the entire sample with a significant difference (p<0.05) between male (13.4%) and female farmers (12.2%). The determinants of adoption of DTM varieties for both male and female farmers were age of the household head, education, source of seed, and level of awareness, specific to male farmers was educational status of the respondents while farm size was specific to female famers. It was concluded that policy strategies aimed at improving the uptake of DTM varieties must consider equality in male and female farmers’ access to resources such as credit, labour and land. Keywords: Gender, Drought-tolerant, Maize varieties, Adoption, Ghana. DOI: 10.7176/JBAH/11-20-04 Publication date:October 31st 202

    Structure-function analysis of the curli accessory protein CsgE defines surfaces essential for coordinating amyloid fiber formation

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    Curli amyloid fibers are produced as part of the extracellular biofilm matrix and are composed primarily of the major structural subunit CsgA. The CsgE chaperone facilitates the secretion of CsgA through CsgG by forming a cap at the base of the nonameric CsgG outer membrane pore. We elucidated a series of finely tuned nonpolar and charge-charge interactions that facilitate the oligomerization of CsgE and its ability to transport unfolded CsgA to CsgG for translocation. CsgE oligomerization in vitro is temperature dependent and is disrupted by mutations in the W48 and F79 residues. Using nuclear magnetic resonance (NMR), we identified two regions of CsgE involved in the CsgE-CsgA interaction: a head comprising a positively charged patch centered around R47 and a stem comprising a negatively charged patch containing E31 and E85. Negatively charged residues in the intrinsically disordered N- and C-terminal “tails” were not implicated in this interaction. Head and stem residues were mutated and interrogated using in vivo measurements of curli production and in vitro amyloid polymerization assays. The R47 head residue of CsgE is required for stabilization of CsgA- and CsgE-mediated curli fiber formation. Mutation of the E31 and E85 stem residues to positively charged side chains decreased CsgE-mediated curli fiber formation but increased CsgE-mediated stabilization of CsgA. No single-amino-acid substitutions in the head, stem, or tail regions affected the ability of CsgE to cap the CsgG pore as determined by a bile salt sensitivity assay. These mechanistic insights into the directed assembly of functional amyloids in extracellular biofilms elucidate possible targets for biofilm-associated bacterial infections.Curli represent a class of functional amyloid fibers produced by Escherichia coli and other Gram-negative bacteria that serve as protein scaffolds in the extracellular biofilm matrix. Despite the lack of sequence conservation among different amyloidogenic proteins, the structural and biophysical properties of functional amyloids such as curli closely resemble those of amyloids associated with several common neurodegenerative diseases. These parallels are underscored by the observation that certain proteins and chemicals can prevent amyloid formation by the major curli subunit CsgA and by alpha-synuclein, the amyloid-forming protein found in Lewy bodies during Parkinson’s disease. CsgA subunits are targeted to the CsgG outer membrane pore by CsgE prior to secretion and assembly into fibers. Here, we use biophysical, biochemical, and genetic approaches to elucidate a mechanistic understanding of CsgE function in curli biogenesis

    A dynamic portal for a community-driven, continuously updated classification of Fungi and fungus-like organisms: outlineoffungi.org

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    The website http://outlineoffungi.org, is launched to provide a continuous up-to-date classification of the kingdom Fungi (including fossil fungi) and fungus-like taxa. This is based on recent publications and on the outline of fungi and fungus-like taxa published recently (Mycosphere 11, 1060-1456, Doi: 10.5943/mycosphere/11/1/8). The website is continuously updated according to latest classification schemes, and will present an important platform for researchers, industries, government officials and other users. Users can provide input about missing genera, new genera, and new data. They will also have the opportunity to express their opinions on classifications with notes published in the 'Notes' section of the webpage following review and editing by the curators and independent experts. The website will provide a system to stay abreast of the continuous changes in fungal classification and provide a general consensus on the systematics of fungi

    Nipah virus V protein binding alters MDA5 helicase folding dynamics

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    Nipah virus (NiV) is an emerging and deadly zoonotic paramyxovirus that is responsible for periodic epidemics of acute respiratory illness and encephalitis in humans. Previous studies have shown that the NiV V protein antagonizes host antiviral immunity, but the molecular mechanism is incompletely understood. To address this gap, we biochemically characterized NiV V binding to the host pattern recognition receptor MDA5. We find that the C-terminal domain of NiV V (

    Cryo-EM analysis of Ebola virus nucleocapsid-like assembly

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    This protocol describes the reconstitution of the filamentous Ebola virus nucleocapsid-like assembl

    Human And Murine Ifit1 Proteins Do Not Restrict Infection Of Negative-sense Rna Viruses Of The Orthomyxoviridae, Bunyaviridae, And Filoviridae Families

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    Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) is a host protein with reported cell-intrinsic antiviral activity against several RNA viruses. The proposed basis for the activity against negative-sense RNA viruses is the binding to exposed 5'-triphosphates (5'-ppp) on the genome of viral RNA. However, recent studies reported relatively low binding affinities of IFIT1 for 5'-ppp RNA, suggesting that IFIT1 may not interact efficiently with this moiety under physiological conditions. To evaluate the ability of IFIT1 to have an impact on negative-sense RNA viruses, we infected Ifit1(-/-) and wild-type control mice and primary cells with four negative-sense RNA viruses (influenza A virus [IAV], La Crosse virus [LACV], Oropouche virus [OROV], and Ebola virus) corresponding to three distinct families. Unexpectedly, a lack of Ifit1 gene expression did not result in increased infection by any of these viruses in cell culture. Analogously, morbidity, mortality, and viral burdens in tissues were identical between Ifit1(-/-) and control mice after infection with IAV, LACV, or OROV. Finally, deletion of the human IFIT1 protein in A549 cells did not affect IAV replication or infection, and reciprocally, ectopic expression of IFIT1 in HEK293T cells did not inhibit IAV infection. To explain the lack of antiviral activity against IAV, we measured the binding affinity of IFIT1 for RNA oligonucleotides resembling the 5' ends of IAV gene segments. The affinity for 5'-ppp RNA was approximately 10-fold lower than that for non-2'-O-methylated (cap 0) RNA oligonucleotides. Based on this analysis, we conclude that IFIT1 is not a dominant restriction factor against negative-sense RNA viruses. IMPORTANCE Negative-sense RNA viruses, including influenza virus and Ebola virus, have been responsible for some of the most deadly outbreaks in recent history. The host interferon response and induction of antiviral genes contribute to the control of infections by these viruses. IFIT1 is highly induced after virus infection and reportedly has antiviral activity against several RNA and DNA viruses. However, its role in restricting infection by negative-sense RNA viruses remains unclear. In this study, we evaluated the ability of IFIT1 to inhibit negative-sense RNA virus replication and pathogenesis both in vitro and in vivo. Detailed cell culture and animal studies demonstrated that IFIT1 is not a dominant restriction factor against three different families of negative-sense RNA viruses.891894659476Division of Intramural Research, NIAID, NIHNIH grant [F32 AI112274][U54 AI057160][R01 AI104972][R01 AI104002

    Deep seafloor magnetic observations under GEOSTAR project

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    Performing good quality magnetic observations is not an easy task; making them in the extreme marine environment is even much more challenging. The European funded GEOSTAR project succeeded in reaching this difficult goal. After the shallow seawater test experiment performed in the Adriatic sea in 1998, the main aims of the GEOSTAR project were achieved two years later during the six-month deep seafloor mission in the Tyrrhenian sea at around 2 km depth. Details and results about the shallow seawater mission in the Adriatic sea were published in previous articles; this paper is concerned with the deep seafloor mission in the Tyrrhenian sea close to Ustica Island and presents some results related to the geomagnetic recordings
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