26 research outputs found

    Virulence of South African isolates of Haemophilus paragallinarum. Part 3: Experimentally produced NAD-independent isolate

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    A NAD-dependent isolate 46 (C-3) of Haemophilus paragallinarum, which was previously demonstrated to be of high virulence, was transformed to NAD independence using a plasmid isolated from a naturally occurring NAD-independent isolate of H. paragallinarum. The transformation was performed by two different methods and the identity of all of the isolates, before and after transformation was confirmed using a H. paragallinarum-specific PCR test. The transformed NAD-independent serovar C-3 isolate and the wild-type serovar C-3 isolate were used to experimentally infect vaccinated layer chickens. It was shown that the transformation to NAD independence significantly altered the virulence of the serovar C-3 isolate that was used in the transformation experiment. The mechanisms responsible for a decrease in virulence are not clear, but may be related to the pathology of the transformed isolate in the sinus of the chickens.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

    Leucocyte count and C-reactive protein cannot be relied upon in the diagnosis of acute appendicitis in HIV-infected patients

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    BACKGROUND: South Africa has the highest prevalence of human immunodeficiency virus (HIV) infection in the world, and is commonly found in association with appendicitis. Atypical presentation of appendicitis in the presence of HIV infection makes clinical diagnosis of appendicitis unreliable, and inflammatory markers are commonly used as adjuncts. The aim of this study was ascertain the value of inflammatory markers in the diagnosis of appendicitis in patients with and without HIV infection. METHODS: Patients with acute appendicitis were studied and divided into HIV-infected and HIV-uninfected groups. Symptoms, and systemic and local signs were recorded. Appendiceal pathology was classified as simple or as complicated by abscess, phlegmon or perforation. Total white cell count (WCC) and C-reactive protein (CRP) were chosen as inflammatory markers. Findings were compared between the two groups. RESULTS: The study population consisted of 125 patients, of whom 26 (20.8 per cent) had HIV infection. Clinical manifestations did not differ statistically, and there was no difference in the incidence of simple or complicated appendicitis between the two groups. The mean CRP level was significantly higher in HIV-infected patients (194.9 mg/l versus 138.9 mg/l in HIV-uninfected patients; P¼0.049), and mean WCC (x109/L) was significantly lower (11.07 versus 14.17 109/l respectively; P¼0.010) CONCLUSION: Clinical manifestations and pathology did not differ between HIV-infected and HIV-uninfected patients with appendicitis, except that the WCC response was significantly attenuated and CRP levels were generally higher in the presence of HIV infection.https://academic.oup.com/bjsopenpm2021Surger

    Identifying the Professional Knowledge Base for Multi-Grade Teaching

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    Most countries have made significant progress towards achieving the Millennium Development Goal of Universal Primary Education by setting up multi-grade schools in rural and remote areas. The new Sustainable Development Goal for education specifies Quality Education. This paper reports a small-scale qualitative study of teachers and teaching principals in multi-grade rural schools in Australia, focusing on identifying the professional knowledge base required for teachers in such contexts. Such a knowledge base is essential for improving the quality of multi-grade teaching. Interviews and observations revealed that multi-grade teachers need to develop the skills of learner grouping, organisation and routines, curriculum mapping, differentiating the curriculum, multi-level assessment, planning, and time management. Professional learning for multi-grade teachers will help them to implement increasingly effective methods for providing a quality education for the diverse range of learners in their classrooms

    DNA sequence incongruence and inconsistent morphology obscure species boundaries in the Teratosphaeria suttonii species complex.

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    Teratosphaeria suttonii (= Kirramyces epicoccoides) is a leaf pathogen that can cause premature defoliation, reduced growth and vigosr and subsequent tree death of many Eucalyptus species. Although the fungus primarily infects mature leaves in the lower canopy, infections can spread to younger leaves during continued epidemics or when trees are stressed. Teratosphaeria suttonii has a wide distribution in Australia and has been introduced to many other parts of the world, most probably with germplasm used to establish plantations. The aim of this study was to establish the phylogenetic relationships between T. suttonii isolates from different countries and to consider whether cryptic species exist in a species complex. DNA from parts of the nuclear ribosomal internal transcribed spacer (ITS), β-tubulin and elongation factor-1α genes was sequenced and analyzed for isolates from throughout the range of T. suttonii in Australia, and from six countries (China, Indonesia, South Africa, Uruguay, USA and Vietnam) where the pathogen is introduced. Morphometrics of conidia produced both in vivo and in vitro were also considered. Analysis of the sequence data resulted in incongruent genealogies. Furthermore, groups of isolates in the genealogies could not be linked to area of origin. Likewise differences in conidial morphology could not be linked to any of the phylogenetic groups. There was no evidence of distinct species boundaries and isolates from Australia were closely related to those from other parts of the world. The results of this study support the treatment of T. suttonii as a morphologically and genetically diverse species in its natural range in Australia. The diversity is reflected in introduced populations.National Research Foundation (NRF), members of the Tree Protection Co-operative Program (TPCP),Centre of Excellence in Tree Health Biotechnology (CTHB), University of Pretoria, South Africa, National Manpower Development Secretariat (NMDS), Lesotho and Murdoch University.http://www.springer.com/life+sci/microbiology/journal/10267nf201

    Data from: Multiple introductions from multiple sources: invasion patterns for an important eucalyptus leaf pathogen

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    Many population studies on invasive plant pathogens are undertaken without knowing the center of origin of the pathogen. Most leaf pathogens of Eucalyptus originate in Australia and consequently with indigenous populations available, and it is possible to study the pathways of invasion. Teratosphaeria suttonii is a commonly occurring leaf pathogen of Eucalyptus species, naturally distributed in tropical and subtropical regions of eastern Australia where it is regarded as a minor pathogen infecting older leaves; however, repeated infections, especially in exotic plantations, can result in severe defoliation and tree deaths. Nine polymorphic microsatellite markers were used to assess the genetic structure of 11 populations of T. suttonii of which four where from within its native range in eastern Australia and the remaining seven from exotic Eucalyptus plantations. Indigenous populations exhibited high allele and haplotype diversity, predominantly clonal reproduction, high population differentiation, and low gene flow. The diversity of the invasive populations varied widely, but in general, the younger the plantation industry in a country or region, the lower the diversity of T. suttonii. Historical gene flow was from Australia, and while self-recruitment was dominant in all populations, there was evidence for contemporary gene flow, with South Africa being the most common source and Uruguay the most common sink population. This points distinctly to human activities underlying long-distance spread of this pathogen, and it highlights lessons to be learned regarding quarantine

    Data from: Multiple introductions from multiple sources: invasion patterns for an important eucalyptus leaf pathogen

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    Many population studies on invasive plant pathogens are undertaken without knowing the center of origin of the pathogen. Most leaf pathogens of Eucalyptus originate in Australia and consequently with indigenous populations available, and it is possible to study the pathways of invasion. Teratosphaeria suttonii is a commonly occurring leaf pathogen of Eucalyptus species, naturally distributed in tropical and subtropical regions of eastern Australia where it is regarded as a minor pathogen infecting older leaves; however, repeated infections, especially in exotic plantations, can result in severe defoliation and tree deaths. Nine polymorphic microsatellite markers were used to assess the genetic structure of 11 populations of T. suttonii of which four where from within its native range in eastern Australia and the remaining seven from exotic Eucalyptus plantations. Indigenous populations exhibited high allele and haplotype diversity, predominantly clonal reproduction, high population differentiation, and low gene flow. The diversity of the invasive populations varied widely, but in general, the younger the plantation industry in a country or region, the lower the diversity of T. suttonii. Historical gene flow was from Australia, and while self-recruitment was dominant in all populations, there was evidence for contemporary gene flow, with South Africa being the most common source and Uruguay the most common sink population. This points distinctly to human activities underlying long-distance spread of this pathogen, and it highlights lessons to be learned regarding quarantine

    Investigation of Virgin Coals and Coals Subjected to a Mild Acid Treatment

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    A quantitative determination of the relative marcasite/pyrite contents in virgin coals is possible by means of 57 Fe Mössbauer spectroscopy. Complications arise, however, when iron-containing silicates, carbonates, or other salts are present. The application of a mild chemical treatment involving hydrofluoric acid has been employed to remove these Fe-containing phases while leaving the iron-disulfide phases unaffected.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42925/1/10751_2004_Article_331047.pd

    data

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    The data file contain the allele size for data from nine microsatellite loci. The first column contains the population code and the second column contains the isolate code

    Hospital admissions for skin and soft tissue infections in a population with endemic scabies: A prospective study in Fiji, 2018-2019

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    Scabies is an important predisposing factor for impetigo but its role in more serious skin and soft tissue infections (SSTIs) is not well understood. Information is limited on incidence of SSTIs in the presence of endemic scabies. We conducted a prospective study of hospital admissions for SSTIs in the Northern Division of Fiji (population: 131,914). Prospective surveillance for admissions with impetigo, abscess, cellulitis, wound infection, pyomyositis, necrotizing fasciitis, infected scabies, and crusted scabies was conducted at the Division's referral hospital between 2018 to 2019. Information was collected on demographic characteristics, clinical features, microbiology, treatment and outcomes. Over the study period, 788 SSTI admissions were recorded corresponding to a population incidence 647 per 100,000 person-years (95%CI 571-660). Incidence was highest at the extremes of age with peak incidence in children aged <5 years (908 per 100,000) and those aged ≥65 years (1127 per 100,000). Incidence was 1.7 times higher among the Indigenous Fijian population (753 per 100,000) compared to other ethnicities (442 per 100,000). Overall case fatality rate was 3.3%, and 10.8% for those aged ≥65 years. Scabies was diagnosed concurrently in 7.6% of all patients and in 24.6% of admitted children <5 years. There is a very high burden of hospital admissions for SSTIs in Fiji compared to high-income settings especially among the youngest, oldest and indigenous population which is concordant with scabies and impetigo distribution in this population. Our findings highlight the need for strategies to reduce the burden of SSTIs in Fiji and similar settings

    Tests of a density-based local pseudopotential for sixteen simple metals

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    A comprehensive study of the lattice dynamics, elastic moduli, and liquid metal resistivities for 16 simple metals in the bcc and fcc crystal structures is made using a density-based local pseudopotential. The phonon frequencies exhibit excellent agreement with both experiment and nonlocal pseudopotential theory. The bulk modulus is evaluated by the long wave and homogeneous deformation methods, which agree after a correction is applied to the former. Calculated bulk and Voigt shear moduli are insensitive to crystal structure, and long-wavelength soft modes are found in certain cases. Resistivity calculations confirm that electrons scatter off the whole Kohn-Sham potential, including its exchange-correlation part as well as its Hartree part. All of these results are found in second-order pseudopotential perturbation theory. However, the effect of a nonperturbative treatment on the calculated lattice constant is not negligible, showing that higher-order contributions have been subsumed into the pseudopotential by construction. For bcc sodium, the band structures of local and nonlocal pseudopotentials are found to be almost identica
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