Preparation of Magnetically Driven Nickel Phosphide Nanowires and Their Electrochemical Properties

In this study, nickel phosphide nanowires with various structures and compositions were fabricated for the first time via magnetically-assisted liquid phase synthesis. The curvature and aspect ratio of the nanowires largely depended on the strength of the magnetic field applied during synthesis. Their phosphorus content together with the morphology were significantly modified according to the pH and reducing agent concentration. Nanowires with different structures and phosphorus contents were preliminarily tested for their capabilities to serve in general electrochemical applications. The degree of reaction (i.e., amount of reaction charge) increased with increases in the reaction area and phosphorus content of the nanowires. The rate characteristics of the reaction showed a peculiar increasing trend for a small reaction surface area and low phosphorus content. A change in the ohmic overpotential according to the nanowire curvature (aspect ratio) and porosity was suggested to be the reason for this unusual trend. Electrodes with high phosphorus contents or high reaction surface areas rapidly deteriorated during repetitive redox reactions. Based on the results for the degradation degree, the effect of the reaction surface area dominated that of the phosphorus content in the deterioration of the nickel phosphide nanowires.

Effects of Root Zone Warming on Maize Seedling Growth and Photosynthetic Characteristics Under Different Phosphorus Levels

Phosphorus content and root zone temperature are two major environmental factors affecting maize growth. Both low phosphorus and root zone high temperature stress significantly affect the growth of maize, but the comprehensive effects of phosphorus deficiency and root zone warming are less studied. This study aimed to explore the effects of phosphorus deficiency and root zone warming on the root absorption capacity, total phosphorus content, and photosynthetic fluorescence parameters of maize seedlings. The results showed that maize shoots and roots had different responses to root zone warming and phosphorus deficiency. Properly increasing the root zone temperature was beneficial to the growth of maize seedlings, but when the root zone temperature was too high, it significantly affected the root and shoot development of maize seedlings. The root zone warming had a more significant impact on the root system, while phosphorus deficiency had a greater impact on the shoots. Phosphorus content and root zone warming had a strong interaction. Under the comprehensive influence of normal phosphorus supply and medium temperature in the root zone, the growth of maize seedlings was the best. Under the combined effects of low phosphorus and high temperature in the root zone, the growth was the worst. Compared with the combination of normal phosphorus and root zone medium temperature treatment, the dry mass of the low-phosphorus root zone high temperature treatment was decreased by 55.80%. Under the condition of low-phosphorus too high root zone temperature reduced root vitality, plant phosphorus content, which in turn affected plant growth and light energy utilization efficiency. In the case of sufficient phosphate fertilizer supply, appropriately increasing the soil temperature in the root zone is beneficial to increase the absorption and utilization of phosphorus by plants and promote the growth and development of maize seedlings.

PHENOTYPIC AND GENETIC PARAMETERS ESTIMATED FOR FRESH CORN UNDER DIFFERENT NUTRIENT AVAILABILITY1

ABSTRACT The objective of this work was to estimate and compare phenotypic and genetic parameters after three cycles of intrapopulation recurrent selection for fresh corn grown under three nutrient availability conditions. Three experiments derived from the same population (MV-003) were conducted to assess the ability of progenies to absorb nutrients, one under adequate fertilization (control; MV-006), one under low nitrogen availability (N; MV-006N), and one under low phosphorus availability (P; MV-006P). The experiments were carried out in randomized blocks, with 64 half-sib progenies and three replications for each nutritional condition. Chlorophyll index, plant height, ear insertion, ear diameter, ear length, unhusked ear yield, and marketable husked ear were evaluated. The populations showed variability for the three nutrient availability conditions. The variability reduced after only three selection cycles; thus, evaluating a higher number of half-sib progenies, above 64, under low N and P availability is indicated. The rates used to identify the most efficient progenies in breeding programs should be close to the appropriate one, with a slow reduction after the selection cycles. The variability will be thus maintained, with a greater possibility of identifying more promising progenies. In addition, the frequency of favorable alleles increases more gradually and effectively. The N and P rate of 60 kg ha-1 is not indicated as a critical level for the initial phase of the program.

Serum Phosphorus and Albumin in Patients Undergoing Peritoneal Dialysis: Interaction and Association With Mortality

Hyperphosphatemia and hypoalbuminemia confer worse clinical outcomes, whether these risk factors interact to predispose to mortality is unclear. In this prospective cohort study, 2,118 patients undergoing incident continuous ambulatory peritoneal dialysis (CAPD) were enrolled and categorized into four groups based on the changing point regarding mortality at 1.5 mmol/L for serum phosphorus and 35 g/L for serum albumin. Risks of all-cause and cardiovascular mortality were examined independently and interactively in overall and subgroups. There was no association between serum phosphorus with all-cause and cardiovascular mortality, but significant interactions (p = 0.02) between phosphorus and albumin existed in overall population. Patients in subgroup with high phosphorus and low albumin were at greater risk of all-cause (HR 1.95, 95%CI 1.27–2.98, p = 0.002) but not cardiovascular mortality (HR 0.37, 95%CI 0.10–1.33, p = 0.13), as compared to those with low phosphorus and high albumin. In contrast, patients with both low parameters had a higher risk of all-cause (HR 1.75, 95%CI 1.22–2.50, p = 0.002) and cardiovascular mortality (HR 1.92, 95%CI 1.07–3.45, p = 0.03). Notably, an elevated risk of both all-cause and cardiovascular mortality was observed in those with low serum albumin, irrespective of phosphorus levels, suggesting low albumin may be useful to identify a higher-risk subgroup of patients undergoing CAPD with different serum phosphorus levels.