9 research outputs found

    Effect of soybean planting patterns on some plant environmental measurements and yield

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    ‘Essex\u27 soybeans (Glycine max (L.) Merr.) were used to investi-gate how the relationship between plant density and distribution and environmental weather factors such as radiation, temperature and soil moisture influences soybean yield. Field studies were conducted during the 1980 growing season on a Sequatchie loam soil at the Plant and Soil Science Field Laboratory near Knoxville, Tennessee. Soybean yields were measured at plant populations of 2, 4, 6, 8, 10, and 12 plants per 30 cm of row in 25 cm, 51 cm, 76 cm, and 102-cm rows. Soil moisture depletion was measured by neutron meter in the middle of the row and adjacent to the row to determine the pattern of soil moisture as affected by different plant populations and row spacings. Incoming radiation was measured at the top of the plant canopy and down vertically in the middle of the row and over the main axis of the plant. Vinyl tipped waterproof probes were used for soil tempera-ture measurements at 8 plants per 30 cm of the row for 25, 51, and 76- cm row spacings. As an average of all plant populations the highest yields were obtained from the 25-cm row spacing. Among plant populations, the yield for 2 plants per 30 cm of row was the lowest regardless of the row spacing. Interactions of the number of plants and row spacings showed that the 25-cm row spacing with 8 or 10 plants per 30 cm of row generally outyielded all other planting patterns. Percent surface soil moisture early in the season was very similar for all planting patterns. Later in the season the pattern of soil moisture was indicated that regardless of row spacing, moisture use in the row was higher than in the middle of the row. Moisture content in wider rows (76, 102 cm) was higher than in narrower rows probably because of less competition among plants to exploit surface moisture and larger area between rows. Yields were reduced in relation to the reduction in surface soil moisture. Soybeans which were grown in narrow rows had a significant effect on solar interception. Number of plants per 30 cm of the row was not as influential on light interception as row spacings. The percent of radiation reaching the soil surface in the middle of the row increased with row width. During the day early in the season at full canopy closure there was no significant difference between middle-of-the-row and in-the-row soil temperatures at 25-cm row spacing. The soil temperature reached its maximum value about 2 hours after the maximum air temperature. Soil temperature difference at time of canopy closure was not significant between the 25-cm and 76-cm row spacings

    Association of staphylococcus cohnii subspecies urealyticum infection with recurrence of renal staghorn stone

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    Abstract Background: Stphylococcus cohnii is an organism of coagulase negative species which is considered as normal flora. However, it has been isolated from urinary tract infections and surgical prostheses but its relation with staghorn stones has not been reported, yet. Case Presentation: A 50-years-old woman presented with left renal staghorn stone in June 2014. She had bilateral staghorn stones 7 years ago. Staphylococcus cohnii subspecies urealyticum were detected from a removed stone. After 7 years, recurrence staghorn stone in her left kidney was diagnosed and patient underwent another surgery. The patient had several attacks of cystitis during these 7 years. The results of stone and urine cultures revealed staphylococcus cohnii subspecies urealyticum. Conclusion: This case report emphasizes a possible association between staphylococcus cohnii subspecies urealyticum infection and recurrence renal staghhorn stone

    Effects of Fertilizers and Priming with KH2PO4 Solution on Emergence and Heterotrophic Growth of Black Cumin (Nigella sativa) Seedling

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    In order to investigate the effects of priming with a KH2Po4 solution on emergence and heterotrophic growth of black cumin (Nigella sativa L.) seedling, a series of experiments were conducted at the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2013 and 2014. A field experiment was conducted as factorial layout based on a randomized complete block design with four replications. The fertilizer resources (vermicompost (V)+Tiobacilus (T), micronized Sulfur (S)+T, V+S+T and control) and three levels of phosphorus (0, 30 and 60 kg.ha-1) were the first and second experimental factors, respectively. In the second experiment, selected treatments (in which showed emergence below 60% in the previous experiment) and seed priming (no priming, hydro priming and three levels of phosphorus (P)-priming as 100, 300 and 500 mM KH2Po4) were the first and second experimental treatments, respectively. Based on the results, the resources of soil amendment (V+T and V+S+T) significantly increased the emergence percentage of black seed (by 50 and 54%, respectively). In addition, seed reserve depletion percentage, seed reserve utilization efficiency and emergence percentage significantly increased by 300 mM KH2PO4 (by 9, 143 and 29%, respectively). There was a significant positive relationship between the weight of mobilized seed P and the emergence percentage of black seeds (R2= 0.90 **)

    Harvest strategy and N fertilizer effects on bioenergy sorghum production

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    Bioenergy sorghum (Sorghum bicolor (L.) Moench) has the potential to be a very important cellulosic feedstock if it can be produced without degrading soil quality. Two important factors for achieving that goal are N management and the amount of residue (i.e. carbon) returned to the soil. This study evaluated two N rates (0 or 280 kg ha-1 yr-1) and three levels of residue return (0, 25%, or 50%) on Weswood silty clay loam near College Station, TX USA. Biomass sorghum was grown continuously from 2009 through 2014. Maximum dry biomass yield (23 Mg ha-1) was produced with added N and 25% residue return in a year with above average precipitation. Overall, N fertilization increased biomass yield by 43 to 104%, while residue return enhanced yield from < 1 to 23% during the six-year study. Averaged for the six years, biomass production for the 0, 25%, and 50% residue return treatments was 16, 20, and 18 Mg ha-1, respectively. Returning 25% of the crop residue significantly increased K uptake in both the 1st and 6th years. Sorghum fertilizer N uptake efficiency (FNUE) with residue return by 2014 was significantly increased compared to 2009 values. Non-limiting N fertilization and 25% residue return significantly increased NO3-N, P, K, and soil organic C (SOC) concentrations in surface (0 to 5 cm) samples and soil total N (TN) and K concentrations within the 60 to 90 cm layer. This study confirms that N fertilization will be required to achieve high biomass sorghum yield and suggests that developing a harvest strategy to return 25% of the crop residue will be sufficient to maintain soil quality

    Health workers adjustment for elimination of Malaria in a low endemic area

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    Background: Malaria elimination efforts face with substantial challenges and the role of health workers in address this challenge, particularly advocates and mobilizes communities. The aim of the study was to explore perceptions of health workers in relation to eliminating malaria in order to better understand the level their involvement in malaria elimination efforts. A qualitative approach was adopted based on key informant interviews with 26 health workers who working at community-level in malaria low endemic areas, southern Iran. Methods: Data were collected through key informant interviews. Data were analyzed using thematic content analysis. Results: Findings reveal that the majority of participants concerned with the imported malaria cases, without to address an effective solution to the issue. Health workers had positive perceptions on their basic knowledge and opinions in relation to their field work with emphases to integrate methods. Participants expressed willingness to contribute to malaria elimination effort. They also emphasized on continuous training, resource mobilization, and support. In addition, their perceptions on malaria elimination policy such as sustained financial investment to achieve elimination and integrated management of vector control were rather negative. Conclusions: A mechanism should be considered that allow the health workers to feedback positively on their quality of their practice to health providers

    Use of ammonium sulphate as a sulphur fertilizer: Implications for ammonia volatilization

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    Ammonium sulphate is widely used as a sulphur (S) fertilizer, constituting about 50% of global S use. Within nitrogen (N) management it is well known that ammonium-based fertilizers are subject to ammonia (NH3) volatilization in soils with pH >7, but this has been overlooked in decision making on S fertilization. We reviewed 41 publications reporting measurements of NH3 loss from ammonium sulphate in 16 countries covering a wide range of soil types and climates. In field experiments loss was mostly 7.0 there was a wide range of losses (0-66%), with many in the 20-40% range and some indication of increased loss (ca. 5-15%) in soils with pH 6.5-7.0. We estimate that replacing ammonium sulphate with a different form of S for arable crops could decrease NH3 emissions from this source by 90%, even taking account of likely emissions from alternative fertilizers to replace the N, but chosen for low NH3 emission. In temperate climates emission from soils of pH >7.0 would decrease from 35.7 to 3.6 t NH3 per kt ammonium sulphate replaced. Other sources of S are readily available including single superphosphate, potassium sulphate, magnesium sulphate, calcium sulphate dihydrate (gypsum) and polyhalite (Polysulphate). In view of the large areas of high pH soils globally, this change of selection of S fertilizer would make a significant contribution to decreasing NH3 emissions worldwide, contributing to necessary cuts to meet agreed ceilings under the Gothenburg Convention
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