42 research outputs found
Complete Genome Sequence of the N2-Fixing Broad Host Range Endophyte Klebsiella pneumoniae 342 and Virulence Predictions Verified in Mice
We report here the sequencing and analysis of the genome of the nitrogen-fixing endophyte, Klebsiella pneumoniae 342. Although K. pneumoniae 342 is a member of the enteric bacteria, it serves as a model for studies of endophytic, plant-bacterial associations due to its efficient colonization of plant tissues (including maize and wheat, two of the most important crops in the world), while maintaining a mutualistic relationship that encompasses supplying organic nitrogen to the host plant. Genomic analysis examined K. pneumoniae 342 for the presence of previously identified genes from other bacteria involved in colonization of, or growth in, plants. From this set, approximately one-third were identified in K. pneumoniae 342, suggesting additional factors most likely contribute to its endophytic lifestyle. Comparative genome analyses were used to provide new insights into this question. Results included the identification of metabolic pathways and other features devoted to processing plant-derived cellulosic and aromatic compounds, and a robust complement of transport genes (15.4%), one of the highest percentages in bacterial genomes sequenced. Although virulence and antibiotic resistance genes were predicted, experiments conducted using mouse models showed pathogenicity to be attenuated in this strain. Comparative genomic analyses with the presumed human pathogen K. pneumoniae MGH78578 revealed that MGH78578 apparently cannot fix nitrogen, and the distribution of genes essential to surface attachment, secretion, transport, and regulation and signaling varied between each genome, which may indicate critical divergences between the strains that influence their preferred host ranges and lifestyles (endophytic plant associations for K. pneumoniae 342 and presumably human pathogenesis for MGH78578). Little genome information is available concerning endophytic bacteria. The K. pneumoniae 342 genome will drive new research into this less-understood, but important category of bacterial-plant host relationships, which could ultimately enhance growth and nutrition of important agricultural crops and development of plant-derived products and biofuels
Effect of mound height and cassava cultivar on cassava performance under a fluctuating water table
Field experiments were conducted at Ibadan and Bida in Nigeria, west Africa, to investigate the effect of mound height and cassava cultivar on cassava performance (tuber yield, top yield, tuber length, and plant height). In the Ibadan site, where the soil surface become waterlogged before cassava harvesting, cassava tuber yield, top yield, and tuber length among mounds were statistically different. But, between cultivars only tuber yield and tuber length were significantly different. In the Bida site, where the water table was deep only top yields among mounds were significantly different while between cultivars tuber and top yield were significantly different. The results of this study indicate that the 30 cm high mound, at both sites, gave the least performance in tuber yield, top yield, tuber length and plant height. However, in both sites, cassava performance among the 60, 90 and 120 cm high mounds were not significantly different. Also, in Ibadan site, all the 30 cm and some 60 cm high mounds showed symptoms of chlorosis and stunted vegetative growth as well as tuber rot. No such symptoms were observed at the Bida site
Optimum centerpivot irrigation system design with tillage effects
A method is presented for designing the outer‐end sprinkler of a center‐pivot irrigation system to prevent surface runoff. The smallest wetted diameter, for which soil infiltration capacity equalled or exceeded nozzle application rate, was determined by equating a nozzle application rate relationship and a Green and Ampt infiltration rate relationship. The computed wetted diameter was used in developing relationships to select nozzle type, orifice diameter, and operating pressure. Sensitivity analysis determined that wetted diameter is primarily sensitive to soil characteristics related to infiltration and to evapo‐transpiration rate. Examples illustrated variations in irrigation system design because of tillage system. Greater operating pressure of an irrigation system is necessary to prevent runoff if the tillage system does not prevent soil surface crusting or compaction by raindrops. Considering a no‐till system resulted in the selection of a low‐pressure impact sprinkler instead of a conventional high‐ or medium‐pressure impact sprinkler. Therefore, the developed methodology can be used to design the optimum center pivot irrigation system for given soil, climate, cropping pattern, and tillage practices
The Dambo ecosystem of the Diamphwe and Lilongwe River Catchments in Central Malawi. I. Appraisal of Resources Availability and Use
No abstract availabl
The Dambo Ecosystem of the Diamphwe and Lilongwe River Catchments. II Appraisal of potential indicators of limits to resource availability and use
No abstract availabl
Role of tubularization of urethral plate in development of urethrocutaneous fistula post hypospadias repair
Introduction: This study aimed to demonstrate the outcome of hypospadias repair in the pediatric population using the tubularized urethral plate technique and to compare the incidence of fistula between incised and unincised urethral plate.
Methodology: This is a retrospective cohort study of pediatric patients who had hypospadias repair in a tertiary hospital in Jeddah, Saudi Arabia, between January 2000 and December 2012. They were divided into two main groups according to the status of the urethral plate: Group A included patients who had incision of the urethral plate just before tubularization, and Group B included patients who underwent tubularization without incision.
Results: After reviewing 310 medical records, 106 patients were included in the final analysis, with a median age of 2 years (interquartile range = 3 years). There was no statistically significant relationship between types of hypospadias and the development of fistula (P = 0.26). In Group A, we identified 87 patients (82%), and in Group B, there were 19 patients (18%). The overall incidence of fistula was 34.9% (n = 37). The incidence of fistula in Groups A and B was 36% (n = 31) and 32% (n = 6), respectively. This difference was not statistically significant. Despite a high fistula rate, only 12 patients (11%) were required to repeat surgery.
Conclusion: Incision of the urethral plate did not affect the fistula rate. In comparison to international literature, the incidence of fistula was significantly higher which could be explained by the fact that one-third of those patients had a previous hypospadias repair
Risk factors of anaemia and iron deficiency in Somali children and women: Findings from the 2019 Somalia Micronutrient Survey
There are limited data on the prevalence of anaemia and iron deficiency (ID) in Somalia. To address this data gap, Somalia's 2019 micronutrient survey assessed the prevalence of anaemia and ID in children (6-59 months) and non-pregnant women of reproductive age (15-49 years). The survey also collected data on vitamin A deficiency, inflammation, malaria and other potential risk factors for anaemia and ID. Multivariable Poisson regressions models were used to identify the risk factors for anaemia and ID in children and women. Among children, the prevalence of anaemia and ID were 43.4% and 47.2%, respectively. Approximately 36% and 6% of anaemia were attributable to iron and vitamin A deficiencies, respectively, whereas household possession of soap was associated with approximately 11% fewer cases of anaemia. ID in children was associated with vitamin A deficiency and stunting, whereas inflammation was associated with iron sufficiency. Among women, 40.3% were anaemic, and 49.7% were iron deficient. In women, ID and number of births were significantly associated with anaemia in multivariate models, and approximately 42% of anaemia in women was attributable to ID. Increased parity was associated with ID, and incubation and early convalescent inflammation was associated with ID, whereas late convalescent inflammation was associated with iron sufficiency. ID is the main risk factor of anaemia in both women and children and contributed to a substantial portion of the anaemia cases. To tackle both anaemia and ID in Somalia, food assistance and micronutrient-specific programmes (e.g. micronutrient powders and iron supplements) should be enhanced
Insights into plant cell wall degradation from the genome sequence of the soil bacterium Cellvibrio japonicus
Risk factors of anaemia and iron deficiency in Somali children and women: findings from the 2019 Somalia Micronutrient Survey
There are limited data on the prevalence of anaemia and iron deficiency (ID) in Somalia. To address this data gap, Somalia's 2019 micronutrient survey assessed the prevalence of anaemia and ID in children (6–59 months) and non-pregnant women of reproductive age (15–49 years). The survey also collected data on vitamin A deficiency, inflammation, malaria and other potential risk factors for anaemia and ID. Multivariable Poisson regressions models were used to identify the risk factors for anaemia and ID in children and women. Among children, the prevalence of anaemia and ID were 43.4% and 47.2%, respectively. Approximately 36% and 6% of anaemia were attributable to iron and vitamin A deficiencies, respectively, whereas household possession of soap was associated with approximately 11% fewer cases of anaemia. ID in children was associated with vitamin A deficiency and stunting, whereas inflammation was associated with iron sufficiency. Among women, 40.3% were anaemic, and 49.7% were iron deficient. In women, ID and number of births were significantly associated with anaemia in multivariate models, and approximately 42% of anaemia in women was attributable to ID. Increased parity was associated with ID, and incubation and early convalescent inflammation was associated with ID, whereas late convalescent inflammation was associated with iron sufficiency. ID is the main risk factor of anaemia in both women and children and contributed to a substantial portion of the anaemia cases. To tackle both anaemia and ID in Somalia, food assistance and micronutrient-specific programmes (e.g. micronutrient powders and iron supplements) should be enhanced