Search Results - (Author, Cooperation:G. Carmona)

2013-02-22

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Aging/genetics/pathology/*physiology ; Animals ; Apoptosis ; DNA Damage ; Fibrosis/genetics/pathology ; Gene Deletion ; *Gene Expression Regulation ; Gene Knockout Techniques ; Genetic Therapy ; Heart/*physiology ; Mice ; Mice, Inbred C57BL ; MicroRNAs/*genetics/metabolism ; Myocardial Infarction/genetics/pathology/therapy ; Myocardium/cytology/*metabolism/pathology ; Myocytes, Cardiac/cytology/metabolism/pathology ; Substrate Specificity ; Telomere/genetics/metabolism

2018-01-04

Institute of Physics (IOP)

1755-1307

1755-1315

Geography

Geosciences

Physics

2018-01-04

Institute of Physics (IOP)

1755-1307

1755-1315

Geography

Geosciences

Physics

0038-0717

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Geosciences

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Electronic Resource

1573-0867

Available phosphorus ; biological nitrogen fixation ; phosphate rock (PR) ; soybean

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract Very little information is available concerning the effect of phosphate rock (PR) sources on biological nitrogen fixation (BNF) in legume crops. In a greenhouse study, the15N isotopic dilution technique was used to compare the effectiveness of three sources of PR (Hahotoe rock, Togo; Tilemsi rock, Mali; and Sechura rock, Peru) with that of triple superphosphate (TSP) in increasing soybean seed yield and the amounts of N fixed by the soybean crop. The acid Hartsells slit loam was limed to pH 5.2 and incubated with 8.5 mg N kg−1 as K15NO3 and sucrose for 2 months prior to planting. Then fertilizer P was incorporated into the soil at 12.5, 25, 50, and 100 mg P kg−1 rates. The relative agronomic effectiveness (RAE) of the three PRs with respect to TSP (RAE = 100%) in terms of increasing seed yield was Hahotoe rock = 6.0%, Tilemsi rock = 45.9%, and Sechura rock = 75.2%; this trend followed the same trend as PR reactivity, i.e., Sechura rock 〉 Tilemsi rock 〉 Hahotoe rock. BNF was affected significantly by all the P treatments. Of the total N derived from the three N sources (atmosphere, Ndfa; fertilizer K15NO3, Ndff; and soil, Ndfs), Ndfa was highest with TSP and lowest with Hahotoe rock, whereas the reverse was found with Ndfs. Among various plant parts, more Ndfa was translocated and stored in seeds than in stems + leaves and roots. The RAE values of the three PRs with respect to TSP (RAE = 100%) in terms of influencing the amount of BNF were Hahotoe rock = 3.0%, Tilemsi rock = 43.4%, and Sechura rock = 71.2%. A linear relationship was found between the amount of BNF by the whole soybean plant and the soybean seed yield.

Electronic Resource

1573-0867

KCl ; ammonia volatilization ; urea

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract Ammonia volatilization associated with urea hydrolysis has been shown to be primarily associated with the pH of the soil solution and its buffering ability in the immediate zone of the fertilizer granule. Numerous studies have also shown that these losses can be reduced significantly by the addition of large amounts of KCl with the urea. Because the pH of commercial sources of potash ranges from 6.5 to 9.5, investigations were conducted to determine if the high pH of these K sources had an effect on the ammonia lost from three contrasting soils. Despite large ammonia losses (approximately 50% of N applied) and a significant reduction in loss due to the use of KCl (30%-50% reduction), the experiments showed no effect of potash pH on ammonia loss. It may be concluded that no risk of enhanced ammonia loss can be associated with the use of high-pH potash sources.

Electronic Resource

1573-0867

N efficiency ; nBTPT ; nBPT ; CHTPT ; and CHPT

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract A variety of compounds have been tested as urease inhibitors with the goal of providing a means of reducing ammonia volatilization losses from urea fertilizers when they are applied to the soil surface. Four phosphoric triamide compounds were studied in laboratory experiments to assess their effect on urea hydrolysis, soil ammonium levels, and ammonia volatilization. The compounds N(n-butyl) thiophosphoric triamide (nBTPT), cyclohexyl thiophosphoric triamide (CHTPT), and their oxygen analogs [N-(n-butyl) phosphoric triamide (nBPT) and cyclohexyl phosphoric triamide (CHPT), respectively] were mixed with urea at 0.1% and 0.01% w/w ratios, and the products were applied to the soil surface. A forced-draft apparatus was used to measure ammonia loss. The urea treatment lost 47% of applied N as ammonia in 14 d. The inhibitors applied at 0.1% w/w showed losses of 7%–10% in 14 d; at 0.01%, losses ranged from 13%–30% in the same period. At the 0.1% level, no significant difference was found among the inhibitors in terms of ammonia loss or urea hydrolysis trends. At the 0.01% concentrations, the oxygen analogs showed better urea urease inhibition than did the thio compounds, and their ammonia losses were half those of their sulfur analogs.

Electronic Resource

1435-0661

Springer Online Journal Archives 1860-2000

Geosciences

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

M CaCl2 has been proposed as an improved soil test for evaluating available P from soils treated with phosphate rock (PR) and triple superphosphate (TSP). However, conclusive evidence for this suggestion has not been reported. This study was conducted to evaluate the suitability of the Pi test for both PR and TSP. In a greenhouse study, two acid soils —Hartsells silt loam (fine-loamy, siliceous, thermic Typic Hapludult) and Hiwassee clay loam (fine, kaolinitic, thermic Rhodic Kanhapludult)—were mixed with ground (0.15-mm, 100-mesh) North Carolina (NC) PR or commercial-grade granular TSP at 0 to 300 mg P kg–1 soil. The soil samples were preincubated for 2 wk before maize (Zea mays L.) was planted and grown for 5 wk. Prior to planting, soil samples were analyzed by three soil tests: Bray I, Pi test with 0.01 M CaCl2, and Pi test with 0.02 M KCl. The results showed that NC-PR and TSP were equally effective in increasing dry-matter yield and P uptake by maize in Hartsells soil. North Carolina phosphate rock was approximately 83 and 91% as effective as TSP in increasing dry-matter yield and P uptake, respectively, in Hiwassee soil. When P uptake was plotted against soil test values, both the Bray I and Pi test with CaCl2 underestimated available P from NC-PR for TSP-treated soil. Available soil P estimated by the Pi test using KCl instead of CaCl2 was more closely related to P uptake with both NC-PR and TSP. More P was extracted from NC-PR by the Pi test with KCl than with CaCl2, whereas no effect was observed for TSP.

Electronic Resource