428 research outputs found

    Bacterial-plant associations with special focus on pink-pigmented facultative mehtylotrophic bacteria (PPFMs)

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    The non-infecting, plant-associated bacteria have attracted increased attention for stimulating plant growth and as environmentally friendly plant protection agents. However, further elucidation of these characters and of the modes of action involved is dependent on availability of suitable isolation, culturing and screening procedures. In this thesis, a Pantoea agglomerans strain, selected for its induction of cytokinin-like effects in test plants and its stimulation of plant growth, was found to secret different cytokinins in its culture filtrate as demonstrated by IAC, HPLC and GC-MS. In addition to the known cytokinins, isopenenyladenine, isopentenyladenosine and their 2-methylthiol derivates, it was shown tro also produce the cytokinin, 5'-Deoxyisopentenyladenosine, being isolated from a natural source for the first time. A different group of plant-associated bacteria belonging to the genus Methylobacterium was studied concerning their natural populations, which were followed for two growing seasons in red clover and winter wheat. The populations were higher in red clover than in wheat and changed regularly over the growing season. This pattern was clear and statistically validated in red clover, but was less obvious in winter wheat due to high variability in population sizes. Colonization studies conducted in the greenhouse with gfp-tagged mutatns revealed that phyllosphere colonization occurs by direct contact with the leaf surface. However, in some plants species, like red clover, phyllosphere colonization also occurred via seeds. In addition to their ability to colonize the phyllosphere, members of Methylobacterium were also able to colonize the rhizosphere of the tested plant species. Upon visualization of gfp-tagged bacterial mutants sprayed on the aerial part of red clover, bacterial cells were localized in the grooves between the leaf epidermal cells, which may give them protection and access to methanol. The bacterial cells colonized red clover phyllosphere by forming large aggregates, a feature which is known to increase survival of epiphytic bacteria in the phyllosphere. Several Methylobacterium spp. produce cytokinins, e.g.zeatin riboside, and we demonstrated that three out of 16 isolates were able to produce also indole-3-acetic acid in culture filtrates. Group specific PCR primers, designed as a first step for describing community structure of Methylobacterium spp., were tested for specificity in type strains of different bacterial species. One primer set (404f and 1123r), successfully amplified the 16SrRNA of Methylobacterium spp but not the other tested bacterial genera. T-RFLP profiles of these bacteria were fairly similar in the two tested plant species. However, more differences were observed in T-RFLP profiles of red clover environmental samples than from winter wheat samples. The samples were collected from different locations and at different times during the growing season

    Industrial Building Systems (IBS) as an Alternative Approach for Housing the Poor in Sudan

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    Housing for the poor is one of the foremost troubling issues for governments, since independence, the government of Sudan has pledged to undertake to unravel the housing problem for low-income people, but the growing demand populations far exceed what's on the table to unravel this problem. The research aims this is to review the potential of an industrialized building system (IBS) for low-cost housing provision in Sudan. the current conventional construction system (CBS) that used for this sort of building is linked to several problems: inefficiency, slow delivery rate, poor quality standards but at an equivalent time helps create many roles like doesn’t depend on skilled labor and elegance flexibility. due to its capacity to line up group projects faster than CBS can, the industrialized building system is usually used to meet the urgent need for housing for the displaced because of its ability to equip collective projects quickly and in high quality, the best example of which was used extensively after the Second war in many European countries affected during the war. Although IBS could even be a replacement system in Sudan, it's expected to spread rapidly, with appropriate material value and high quality to satisfy the requirements of the end-user. For more efficient, a system is usually developed that mixes the characteristics of the conventional and industrial systems to unravel the housing problem for the poor in Sudan. The research results are helped the government to spot the possibility of industrial buildings as an appropriate solution to the housing problem in Sudan. Also help the government on the power of industrial buildings as an efficient solution for the housing problem in Sudan, particularly low-income housing. The aims of the research to support government initiatives to affect the poor in Sudan. It is largely debatable due to its importance, and importance to government-supported housing objectives and thus the particular impacts of the initiative and its performance for low-income housing in Sudan

    Ensuring Uptake of Vaccines against SARS-CoV-2

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    Development of Loop-Mediated Isothermal Amplification Assay for Rapid Detection and Analysis of the Root-Knot Nematode Meloidogyne hapla in Soil

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    Soil analysis is crucial for estimating the risk of crop damage by the root-knot nematode Meloidogyne hapla. Here, we developed an analysis assay based on Loop-mediated Isothermal Amplification (LAMP). The LAMP primers were verified for specificity against 10 different nematode species. A manual soil DNA extraction, referred to as SKMM, was developed and compared with a FastDNA kit followed by DNA purification. DNA was extracted with both methods from artificially inoculated soils as well as from naturally infested soil collected from farm fields. The primers exclusively amplified DNA from M. hapla with both colorimetric and real-time LAMP. The detection limit was 193 gene copies and 0.0016 juveniles (12 pg mu L-1) per reaction. DNA concentrations and purity (A(260)/A(230)) were significantly higher using the SKMM procedure compared with the kit. From the field samples collected in 2019, DNA was amplified from 16% of samples extracted with SKMM and from 11% of samples using the kit. Occurrence of M. hapla DNA was confirmed in soil samples from two out of six field soils in 2020 using both real-time LAMP and qPCR. In conclusion, the developed real-time LAMP is a fast and specific assay for detection and quantification of M. hapla DNA in soil

    Maternal immunization: A call to accelerate progress

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    Maternal immunization provides an excellent evidence-based strategy for preventing severe disease and decreasing neonatal and infant mortality. A substantial proportion of these deaths are due to infectious diseases, most of them vaccine-preventable, then, there is a real opportunity for intervention. Maternal immunization has been an underexploited area for many years, with the exception of neonatal tetanus. There are now programs for influenza and acellular pertussis vaccination in many countries and two maternal vaccine targets under development are focused on decreasing the burden of infant respiratory syncytial virus (RSV) and Group B Streptococcus (GBS). Bodies like the Strategic Advisory Group of Experts (SAGE) on Immunization established by the WHO, the Global Vaccine Action Plan (GVAP) and Gavi, The Vaccine Alliance, have recognized the relevance of maternal immunization on several occasions. However, why is the field not moving faster, as one might expect? Major initiatives and programs should consider spelling out more clearly the role and benefits of this intervention and calling for specific actions, including future strategic approaches for the post 2020 immunization strategy following the GVAP; and single out the area as one of its priorities as a key component of immunization across the life course. While waiting for the new vaccines like RSV and GBS and optimizing the use of influenza and pertussis there is momentum now to coordinate efforts, address the missing information and action gaps, and call to accelerate progress

    Development of Novel Experimental Infrastructure for Collecting High-Fidelity Experimental Data for Refrigerant to Air Heat Exchangers

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    Manufactures of fin-and-tube heat exchangers often employ predictive modelling tools in order to reduce development cost and time. These tools require high-fidelity experimental data to validate the accuracy of their predictions. To that end, this paper presents the design and development of a custom-designed pumped refrigerant loop to collect high-fidelity experimental data for fin-and-tube heat exchangers in three operating modes: (1) single-phase refrigerant, (2) evaporator, and (3) condenser mode. It is combined with a small-scale wind tunnel installed in a psychrometric chamber facility for the purpose of validating the recently developed discretized fin-and-tube heat exchanger models (Sarfraz et al., 2019a and 2019b). The pumped refrigerant loop is able to precisely control desired refrigerant test conditions, flowrate to each individual heat exchanger circuit, and has been sized in order to test heat exchanger coils up to a capacity of 5 tons (17.5 kW). A preliminary test plan and uncertainty analysis is presented for the first heat exchanger coil to be tested. The uncertainty analysis showed that the experiment will have the capability of measuring overall coil capacity within ±2%. A design of experiments is also presented, which suggests that 9 tests per coil is an adequate number for minimizing experimental effort. A preliminary experiment was performed which showed that the average air and refrigerant side capacities match to within 1.1% of each other. This provides evidence that the experimental setup has the capability to far exceed the 5% threshold set by ASHRAE Standard 33 (2016)

    Effects of sulphur fertilization in organically cultivated faba bean

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    Optimal seed yield and quality requires that the sulphur (S) demand of faba bean (Vicia faba L.) is ensured. The effect of S fertilization on organic cultivated faba bean was investigated under field conditions during two growing seasons (2017–2018), in Sweden. Kieserite (MgSO4) and gypsum (CaSO4) were applied at a rate of 20 and 40 kg ha-1 to study the effect on faba bean growth, yield, crude protein (CP) content and amino acid (AA) composition. Gypsum and kieserite significantly increased S concentration of faba bean dry matter (DM) in 2017. The S concentration ranged from 0.20% to 0.23% of DM compared to 0.18% in the untreated control. In 2018, kieserite application at 40 kg ha-1 significantly increased S concentration to 0.15% compared to 0.12% in the untreated control. The faba bean plants did, however, not respond neither with increased growth nor increased seed yield. The seed quality in terms of CP and S-containing AA, was not affected by S fertilization, however, significant differences were observed between the experimental sites

    Symbolic Analysis of Waiting for Godot: A Critical Comparison Between the Bible and Quran Symbols in Waiting for Godot

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    Waiting for Godot (1952) is a conventional and remarkable play that is written by Irish author Samuel Beckett. The play Waiting for Godot is part of theater of absurd and it is written during modernism. This research is divided into three different sections and conclusion. Firstly the introduction for this research is given and the twentieth century drama, theater of the absurd, and the summary of the play. Also in an independent section we show other people’s work on the play Waiting for Godot. Later on we clarified the Biblical and Quranic symbols in Waiting for Godot and shows the comparison of the symbols in the holy books Quran and Bible in Waiting for Godot. Eventually, conclusion will be drawn as the final outcome of the study.
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