Effects of Paper-Mill Sludge as a Mulch versus Topsoil Incorporation on Potassium Uptake and the Grain Yield of Rain-Fed Wheat in a High Specific Surface Loess Soil with Illite Dominance in Clay Fraction

A field experiment with rain-fed winter wheat investigated the nutritional aspects of paper-mill sludge as a mulch and incorporated into the topsoil. Treatments with chemical fertilizers were also used as controls. Paper-mill sludge used as mulch with high rate (100 MG ha−1) and also the combined N and K mineral fertilizer treatments increased yield when a low potassium otherwise caused potassium deficiency in wheat with high specific surface soil. High soil Ca : K molar ratio by incorporation lowered potassium uptake and yield, with visual symptoms of potassium deficiency. A very high Gapon selectivity coefficient (KG) for K exchange against Ca + Mg (16.58 (L/mole)0.5) produced a nonlinear normalized exchange isotherm in favor of potassium with these soils containing high illite. Ca and K which are released by sludge decomposition are diverged in soil when mobilized by rain infiltration, lowering Ca : K molar ratio. Low soil Ca : K molar ratio may be expected by surface sludge application relative to incorporation, due to greater rain infiltration through upper soil layers and their effluent pore volumes per unit depth. Ca from triple superphosphate by the P, N, and K mineral fertilizers combined also reduced potassium uptake and yield relative to N and K combined

Theoretical Progression of Work and Life Relationship: A Historical Perspective

In this study we will discuss the historical changes in the work and life relationship which resulted in development of new theories. After an introduction to work-life relationships, different theories of work and life are presented in the second section of this paper. These theories are categories intro three generations based on their characteristics in the historical evolution of work-life studies. In the third section measures of work and life spillovers are described. In section four, critiques of the current methodologies which is being used in the work and life studies are presented. Discussion section which is presented in following section includes some arguments regarding the ways to select the most appropriate theories for work-life studies. Also in this section some recommendations are presented for enhancing the commonly used methodologies of the research on work and life relationships. Finally, in the last section, some recommendations for future studies are presented

The correlation of RNase A enzymatic activity with the changes in the distance between Nepsilon2-His12 and N delta1-His119 upon addition of stabilizing and destabilizing salts.

The effect of stabilizing and destabilizing salts on the catalytic behavior of ribonuclease A (RNase A) was investigated at pH 7.5 and 25 degrees C, using spectrophotometric, viscometric and molecular dynamic methods. The changes in the distance between N(epsilon2) of His(12) and N(delta1) of His(119) at the catalytic center of RNase A upon the addition of sodium sulfate, sodium hydrogen sulfate and sodium thiocyanate were evaluated by molecular dynamic methods. The compactness and expansion in terms of Stokes radius of RNase A upon the addition of sulfate ions as kosmotropic salts, and thiocyanate ion as a chaotropic salt, were estimated by viscometric measurements. Enzyme activity was measured using cytidine 2', 3'-cyclic monophosphate as a substrate. The results from the measurements of distances between N(epsilon2) of His(12) and N(delta1) of His(119) and Stokes radius suggest (i) that the presence of sulfate ions decreases the distance between the catalytic His residues and increases the globular compactness, and (ii) that there is an expansion of the enzyme surface as well as elongation of the catalytic center in the presence of thiocyanate ion. These findings are in agreement with activity measurements

The calcium-free form of atorvastatin inhibits amyloid-β(1–42) aggregation in vitro

Alzheimer's disease is characterized by the presence of extraneuronal amyloid plaques composed of amyloid-beta (A beta) fibrillar aggregates in the brains of patients. In mouse models, it has previously been shown that atorvastatin (Ator), a cholesterol-lowering drug, has some reducing effect on the production of cerebral A beta. A meta-analysis on humans showed moderate effects in the short term but no improvement in the Alzheimer's Disease Assessment Scale-Cognitive Subscale behavioral test. Here, we explore a potential direct effect of Ator on A beta 42 aggregation. Using NMR-based monomer consumption assays and CD spectroscopy, we observed a promoting effect of Ator in its original form (Ator-calcium) on A beta 42 aggregation, as expected because of the presence of calcium ions. The effect was reversed when applying a CaCO3- based calcium ion scavenging method, which was validated by the aforementioned methods as well as thioflavin-T fluorescence assays and transmission electron microscopy. We found that the aggregation was inhibited significantly when the concentration of calcium-free Ator exceeded that of A beta by at least a factor of 2. The H-1-N-15 heteronuclear single quantum correlation and saturation-transfer difference NMR data suggest that calcium-free Ator exerts its effect through interaction with the (KLVF19)-K-16 binding site on the A beta peptide via its aromatic rings as well as hydroxyl and methyl groups. On the other hand, molecular dynamics simulations confirmed that the increasing concentration of Ator is necessary for the inhibition of the conformational transition of A beta from an alpha-helix-dominant to a beta-sheet-dominant structure

Formation of the Stomatal Outer Cuticular Ledge Requires a Guard Cell Wall Proline-Rich Protein

Stomata are formed by a pair of guard cells which have thickened, elastic cell walls to withstand the large increases in turgor pressure that have to be generated to open the pore that they surround. We have characterised FOCL1, a guard cell-expressed, secreted protein with homology to hydroxyproline-rich cell wall proteins. FOCL1-GFP localises to the guard cell outer cuticular ledge and plants lacking FOCL1 produce stomata without a cuticular ledge. Instead the majority of stomatal pores are entirely covered-over by a continuous fusion of the cuticle, and consequently plants have decreased levels of transpiration and display drought tolerance. The focl1 guard cells are larger and less able to reduce the aperture of their stomatal pore in response to closure signals suggesting that the flexibility of guard cell walls is impaired. FOCL1 is also expressed in lateral root initials where it aids lateral root emergence. We propose that FOCL1 acts in these highly specialised cells of the stomata and root to impart cell wall strength at high turgor and/or to facilitate interactions between the cell wall and the cuticle

Stomatal responses to carbon dioxide and light require abscisic acid catabolism in Arabidopsis

In plants, stomata control water loss and CO2 uptake. The aperture and density of stomatal pores, and hence the exchange of gases between the plant and the atmosphere, are controlled by internal factors such as the plant hormone abscisic acid (ABA) and external signals including light and CO2. In this study, we examine the importance of ABA catabolism in the stomatal responses to CO2 and light. By using the ABA 8′-hydroxylase-deficient Arabidopsis thaliana double mutant cyp707a1 cyp707a3, which is unable to break down and instead accumulates high levels of ABA, we reveal the importance of the control of ABA concentration in mediating stomatal responses to CO2 and light. Intriguingly, our experiments suggest that endogenously produced ABA is unable to close stomata in the absence of CO2. Furthermore, we show that when plants are grown in short day conditions ABA breakdown is required for the modulation of both elevated [CO2]-induced stomatal closure and elevated [CO2]-induced reductions in leaf stomatal density. ABA catabolism is also required for the stomatal density response to light intensity, and for the full range of light-induced stomatal opening, suggesting that ABA catabolism is critical for the integration of stomatal responses to a range of environmental stimuli