Browsing by Subject "phosphorus"

Now showing 1 - 6 of 6
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    Balancing the Global Distribution of Phosphorus With a View Toward Sustainability and Equity
    (AGU, 2018) Filippelli, Gabriel M.; Earth Sciences, School of Science
    Limitations in the geological reserves of phosphate rock, the source of fertilizer phosphorus, are not currently considered in agricultural practices or global trade, a very short‐sighted approach considering that there is no “alternative fuel” for plant growth. Thus, it is important to understand the science of phosphorus‐crop growth dynamics as a function of grain type, plant uptake, climate, and past fertilizer phosphorus application history. Recent work on modeling these factors on the global scale (Kvakić et al., 2018) provides the first scientific backdrop for developing an understanding of fertilizer phosphorus balances, and for informing forward‐looking practices and policies that regulate toward long‐term sustainability rather than short‐term profit.
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    The effect of a diet containing 70% protein from plants on mineral metabolism and musculoskeletal health in chronic kidney disease
    (Karger, 2014) Moorthi, Ranjani N.; Armstrong, Cheryl L. H.; Janda, Kevin; Ponsler-Sipes, Kristen; Asplin, John R.; Moe, Sharon M.; Department of Medicine, IU School of Medicine
    BACKGROUND: Chronic Kidney Disease (CKD) is associated with alterations in phosphorus excretion, and increases in fibroblast growth factor (FGF23) and parathyroid hormone (PTH). Plant protein-based phytate-bound phosphorus, is less bioavailable than that from animal sources. Our one-week study that was conducted previously showed that a nearly 100% plant protein-based diet benefits mineral metabolism in CKD; however, this diet may not be acceptable to patients. Here we hypothesize that a diet containing 70% protein from plants has similar efficacy and is tolerated by CKD patients. METHODS: Thirteen subjects with CKD 3-4 received an omnivorous diet containing 70% protein from plants for 4 weeks. The primary outcome was change in 24 h urine phosphorus. Secondary outcomes were changes in serum phosphorus, FGF23, PTH, urine sodium excretion, grip strength and fat free mass. Repeated measures analysis of variance (ANOVA) was used to test differences in parameters over the 4 weeks. RESULTS: Mean age of subjects was 54.8 years. Median eGFR was 26 (IQR 14.7) ml/min/1.73 m(2). Over the 4-week period, urine phosphorus significantly decreased by 215 ± 232 mg/day (p < 0.001). No significant changes in serum FGF23, phosphorus or PTH were noted. Urine sodium and titratable acid decreased significantly on the diet. Hand grip strength and fat-free mass did not change. There were two hyperkalemia events both 5.8 mEq/l, corrected by food substitutions. No other adverse events were observed. CONCLUSIONS: A 70% plant protein diet is safe, tolerated, and efficacious in lowering urine phosphorus excretion and may be an alternative to phosphate binders.
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    Intake of Calcium, Magnesium, and Phosphorus and Risk of Pancreatic Cancer in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial
    (Taylor & Francis, 2021) Hoyt, Margaret; Song, Yiqing; Gao, Sujuan; O'Palka, Jacquelynn; Zhang, Jianjun; Epidemiology, School of Public Health
    ObjectiveFew epidemiological studies have investigated the associations between calcium, magnesium, and phosphorus intake and pancreatic cancer. We examined these associations in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial.MethodsDiet was assessed using the Dietary Questionnaire (DQX) at baseline in the intervention arm and the Dietary History Questionnaire (DHQ) in 1999 or around the third anniversary of randomization in both the intervention and control arms. During a median follow-up of 12.2 years, 279 cases of pancreatic cancer occurred from 58,477 participants who completed DQX; 380 cases arose from 101,622 participants who responded to DHQ over a median follow-up of 8.9 years. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI).ResultsTotal calcium intake was inversely associated with pancreatic cancer [HR (95% CI) for the fourth vs. the first quartiles in the DHQ cohort: 0.67 (0.47, 0.96); p-trend: 0.035]. An inverse association was also observed for total magnesium intake [HR (95% CI) for the fourth vs. the first quartiles in the DQX cohort: 0.61 (0.37, 1.00); p-trend: 0.023]. Reduced risk associated with total calcium intake was confined to subjects with a high fat intake (>73 g/day) in the DHQ cohort (p-interaction: 0.16).ConclusionsThere was not a significant association between dietary phosphorus intake and pancreatic cancer risk in both cohorts. Total intake of calcium and magnesium are associated with a lower pancreatic cancer risk. The effect of total calcium intake was modified by fat intake.
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    Phosphorus and Life on a Water World
    (AGU, 2022-04-01) Filippeli, Gabriel M.; Earth and Environmental Sciences, School of Science
    On Earth, the major mechanism for providing the vital limiting nutrient phosphorus necessary to fuel biological productivity and the long arc of evolution is weathering of exposed continental rocks. It has been presumed that life may not be present on exoplanets with substantially more water than Earth. Many of these “Water Worlds” exist, but without exposed land mass for weathering, there is not a viable mechanism for nutrient delivery and climate stabilization. In novel laboratory experiments performed in chambers designed to mimic the weathering of seafloor basalts in anoxic conditions, Syverson et al. (2021, https://doi.org/10.1029/2021GL094442) found that silicate weathering in these conditions release an adequate amount of phosphorus to fuel a robust biosphere, at least in an idealized system. Perhaps we shouldn't rule out “Water Worlds” as potential harbors for life after all?
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    Pyrite Analysis of an Ordovician Phosphate Rock Core from Southern Indiana
    (Office of the Vice Chancellor for Research, 2016-04-08) Orazi, Daniel
    Understanding the depositional environments that preserve phosphate-rich rock is becoming progressively more important in light of the increasing scarcity of phosphorus. Phosphorus is the primary constituent in one of the most common types of fertilizer, and it is also used in industries ranging from semiconductor production to flame retardant clothing. Phosphate beds are currently accumulating along select active and passive coastal margins through oceanic upwelling. Upwelling occurs when cold deep phosphorus-rich waters flow to the surface from wind-driven circulation. The nutrient-rich waters increase phytoplankton productivity creating an oxygen minimum zone (OMZ) with available dissolved iron. Southern Indiana is home to a deposit of phosphate rock that formed in a drastically different environment. Throughout much of the Ordovician (488.3-443.7 Mya), Indiana was partially submerged by a shallow (~10m-150m deep) tropical inland sea. The area was situated approximately 20o south of the equator in a position that would be similar to modern-day Brazil, as a member of the ancient landmass called Laurentia. The oxygen concentrations of the inland sea control phosphatization and the materialization of other minerals, including pyrite (FeS2). Pyrite formation is fundamental to geochemical proxies used to determine seawater and sediment traits in ancient environments. It can be formed through a variety of pathways including direct precipitation, solid monosulfide conversion, hydrogen sulfide (H2S) reaction, and iron loss preceding oxidation. The distinct mechanisms driving pyrite formation can be determined through the isotopic signature and the abundance of sulfide released through chromium reducible sulfur (CRS) methods. This study seeks to better understand the ancient water column and pore water characteristics of Ordovician Indiana. We present pyrite concentration isotope data and total phosphorous data to better understand the environmental conditions under which these sediments formed. Identifying these characteristics will add significantly to existing knowledge on phosphate accumulation independent of the oceanic upwelling model. Mentor: William P. Gilhooly III, Department of Earth Sciences, School of Science, IUPUI
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    The Spatial Relationship Between Septic System Failure and Environmental Factors in Washington Township, Marion County, Indiana
    (2019-04) Hanson, Brian L.; Johnson, Daniel P.; Lulla, Vijay; Bein, Frederick L.
    Underground septic systems thrive or fail based on the relationship with their local environment. This paper explores ways environmental variables such as soil type, tree roots, degree of slope, and impervious surfaces affect on-site wastewater treatment systems. It also discusses the effects each of these variables may have on a septic system, and the resulting impact a compromised system may have on the surrounding environment. This research focuses on an approximately 20 square mile area of central Washington Township in Marion County, Indiana. This area of central Indiana contains a large septic system owning population in a sampling of different environments such as wooded areas, hilly areas, and a variety of different soil types.