scholarly journals Potassium-magnesium Imbalance Causes Detrimental Effects on Growth, Starch Allocation and Rubisco Activity in Sugarcane Plants 

2021 ◽  
Author(s):  
Ariani Garcia ◽  
Carlos Alexandre Costa Crusciol ◽  
Ciro Antonio Rosolem ◽  
João William Bossolani ◽  
Carlos Antonio Costa Nascimento ◽  
...  
Keyword(s):  
Magnesium Deficiency ◽  
Starch Accumulation ◽  
Published Data ◽  
Rubisco Activity ◽  
High Accumulation ◽  
Positive Effects ◽  
Application Rates ◽  
High K ◽  
Young Leaves ◽  
Low Levels

Abstract While there is abundant literature on the antagonistic interaction between potassium (K) and magnesium (Mg) during root uptake and transport, there is, however, little published data on the interaction between these nutrients within tissue, especially for sugarcane plants having high demand for K and Mg. This study aimed to evaluate the effects of the interactions between K and Mg on growth, starch partitioning, and activity of Rubisco. Plants were grown under controlled greenhouse conditions in nutrient solution with increasing K application rates at low and adequate Mg treatments. Magnesium adequate plants contained much higher amount of starch in roots, stalks and young leaves than the low Mg plants when K applications were at low levels. By contrast, there was a high accumulation of starch in the source leaves of the Mg deficient plants. Magnesium deficiency was also associated with significant decreases in Rubisco activity in leaves. Our results show clearly that high K rates interfere significantly with the positive effects of Mg on plant growth, Rubisco activity and starch accumulation in sink organs such as roots and stalks. It is obvious that the imbalance between K and Mg nutrition in sugarcane may result in important consequences in sugar yield.

scholarly journals Coverage Layout Design Rules and Insertion Utilities for CMP-Related Processes

2020 ◽  
Vol 11 (1) ◽  
pp. 2
Author(s):  
Eitan N. Shauly ◽  
Sagee Rosenthal
Keyword(s):  
Integrated Circuit ◽  
Thermal Effects ◽  
Process Integration ◽  
Proximity Effects ◽  
Published Data ◽  
Metal Gate ◽  
Comprehensive Description ◽  
Advanced Technologies ◽  
High K ◽  
Rf Devices

The continuous scaling needed for higher density and better performance has introduced some new challenges to the planarity processes. This has resulted in new definitions of the layout coverage rules developed by the foundry and provided to the designers. In advanced technologies, the set of rules considers both the global and the local coverage of the front-end-of line (FEOL) dielectric layers, to the back-end-of-line (BEOL) Cu layers and Al layers, to support high-k/Metal Gate process integration. For advance technologies, a new set of rules for dummy feature insertion was developed by the integrated circuit (IC) manufacturers in order to fulfill coverage limits. New models and utilities for fill insertion were developed, taking into consideration the design coverage, thermal effects, sensitive signal line, critical analog and RF devices like inductors, and double patterning requirements, among others. To minimize proximity effects, cell insertion was also introduced. This review is based on published data from leading IC manufacturers with a careful integration of new experimental data accumulated by the authors. We aim to present a typical foundry perspective. The review provides a detailed description of the chemical mechanical polishing (CMP) process and the coverage dependency, followed by a comprehensive description of coverage rules needed for dielectric, poly, and Cu layers used in advanced technologies. Coverage rules verification data are then presented. RF-related aspects of some rules, like the size and the distance of dummy features from inductors, are discussed with additional design-for-manufacturing layout recommendations as developed by the industry.

scholarly journals Wanneer bevordert en wanneer hindert werkdruk het werkplekleren?

2012 ◽  
Vol 25 (1) ◽  
Author(s):  
Joris Van Ruysseveldt ◽  
Marius van Dijke
Keyword(s):  
Workplace Learning ◽  
Learning Opportunities ◽  
Control Model ◽  
Theoretical Frameworks ◽  
Working Adults ◽  
Positive Effects ◽  
Learning Hypothesis ◽  
High Workload ◽  
Low Levels ◽  
The Relationship

When does workload promote workplace learning opportunities, and when does workload hinder workplace learning opportunities? When does workload promote workplace learning opportunities, and when does workload hinder workplace learning opportunities? Building on theoretical frameworks like the Job Demands Control model we tested whether the relationship between workload and employees’ experiences of opportunities for workplace learning is of an inverted u-shaped nature. Furthermore we researched whether autonomy moderates this relationship. We predicted that at moderate levels of autonomy rising workload was associated with increasing learning opportunities at low levels of workload, but with decreasing learning opportunities at high levels of workload. Also, we predicted that low autonomy prevents positive effects of moderate workload from materializing whereas high autonomy makes high workload less destructive to the learning process. We found support for these ideas in a large and heterogeneous sample of Flemish working adults (FWM, 2010). These results integrate conflicting prior findings and extend Karasek’s (1979) active learning hypothesis. They also have clear implications for job redesign practices aiming to promote workplace learning opportunities.

Molecular and physiological mechanisms underlying magnesium-deficiency-induced enlargement, cracking and lignification of Citrus sinensis leaf veins

2020 ◽  
Vol 40 (9) ◽  
pp. 1277-1291 ◽  
Author(s):  
Xin Ye ◽  
Xu-Feng Chen ◽  
Li-Ya Cai ◽  
Ning-Wei Lai ◽  
Chong-Ling Deng ◽  
...  
Keyword(s):  
Cell Wall ◽  
Citrus Sinensis ◽  
Molecular Mechanisms ◽  
Rho Gtpase ◽  
Magnesium Deficiency ◽  
Lignin Biosynthesis ◽  
Starch Accumulation ◽  
Ascorbate Oxidase ◽  
Mg Deficiency ◽  
Leaf Veins

Abstract Little is known about the physiological and molecular mechanisms underlying magnesium (Mg)-deficiency-induced enlargement, cracking and lignification of midribs and main lateral veins of Citrus leaves. Citrus sinensis (L.) Osbeck seedlings were irrigated with nutrient solution at a concentration of 0 (Mg-deficiency) or 2 (Mg-sufficiency) mM Mg(NO3)2 for 16 weeks. Enlargement, cracking and lignification of veins occurred only in lower leaves, but not in upper leaves. Total soluble sugars (glucose + fructose + sucrose), starch and cellulose concentrations were less in Mg-deficiency veins of lower leaves (MDVLL) than those in Mg-sufficiency veins of lower leaves (MSVLL), but lignin concentration was higher in MDVLL than that in MSVLL. However, all four parameters were similar between Mg-deficiency veins of upper leaves (MDVUL) and Mg-sufficiency veins of upper leaves (MSVUL). Using label-free, liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, we identified 1229 and 492 differentially abundant proteins (DAPs) in MDVLL vs MSVLL and MDVUL vs MSVUL, respectively. Magnesium-deficiency-induced alterations of Mg, nonstructural carbohydrates, cell wall components, and protein profiles were greater in veins of lower leaves than those in veins of upper leaves. The increased concentration of lignin in MDVLL vs MSVLL might be caused by the following factors: (i) repression of cellulose and starch accumulation promoted lignin biosynthesis; (ii) abundances of proteins involved in phenylpropanoid biosynthesis pathway, hormone biosynthesis and glutathione metabolism were increased; and (iii) the abundances of the other DAPs [viz., copper/zinc-superoxide dismutase, ascorbate oxidase (AO) and ABC transporters] involved in lignin biosynthesis were elevated. Also, the abundances of several proteins involved in cell wall metabolism (viz., expansins, Rho GTPase-activating protein gacA, AO, monocopper oxidase-like protein and xyloglucan endotransglucosylase/hydrolase) were increased in MDVLL vs MSVLL, which might be responsible for the enlargement and cracking of leaf veins.

scholarly journals THE EFFECT OF ENVIRONMENTAL POTASSIUM AND CALCIUM CONCENTRATIONS ON THE RECOVERY OF THE ACTION POTENTIAL AND RELATED FUNCTIONS OF NERVE

1947 ◽  
Vol 30 (6) ◽  
pp. 493-517 ◽  
Author(s):  
Helen Tredway Graham ◽  
H. A. Blair
Keyword(s):  
Critical Level ◽  
Specific Effect ◽  
The Other ◽  
Level Control ◽  
Definite Effect ◽  
High K ◽  
Low Levels ◽  
K Concentration ◽  
Low K ◽  
Frog Sciatic Nerve

1. When the Ringer's solution applied to isolated frog sciatic nerve contains K+ in concentrations greater than 2 x standard, the height of the spike and of the after-potential is decreased, as is the duration of the after-potential; recovery of height and of excitability following response is delayed; degree and duration of supernormal excitability are decreased; postcathodal depression and postanodal enhancement are increased and prolonged. 2. The nerve functions just listed in general all change in the opposite direction when exposed' to increased environmental [Ca++]. (4.5–20 x standard) or decreased [K+] (0.05–0.2 x standard). The effects of decreased [Ca++] (0.20–0.25 x standard) are indeterminate. 3. When [K+] and [Ca++] are both greater than 2 x standard, whatever the ratio between the concentrations the effects characteristic of high [K+] eventually predominate. However, these effects, except for those involving spike height, are preceded by effects characteristic of high [Ca++] when this cation is present in sufficient excess. 4. When [K+] and [Ca++] are reduced to equal low levels (0.1–0.2 x standard), effects characteristic of low [K+] and high [Ca++] are obtained. 5. The experimentally determined order of ability of the environments to produce changes characteristic of high K+ (which is the reverse of the order of their ability to produce changes characteristic of high [Ca++]), is not the order of their K+ or Ca++ concentrations, nor of the ratio between these concentrations (Table II). 6. The results may be explained by the assumption that the functions investigated are all to greater or less degree controlled by (1) the [K+]/[Ca++] ratio and (2) the K+ concentration, at least when this exceeds a critical level. Control by [K+] is more effective for spike height and its recovery after stimulation than for the other functions. The special rôle of K+ is attributed to an unknown specific effect of this ion which Ca++ is unable to oppose. It is suggested that this K+ effect in general becomes marked on the frog nerve functions investigated when the K+ concentration is somewhat above 2 x standard, while the [K+]/[Ca++] ratio must be changed by a factor of 4 or more before it exerts a definite effect on these functions. 7. In standard and in modified cationic environments, nerve functions vary in the ease with which they manifest changes characteristic of high [K+] or of high [Ca++]. 8. The after-potential functions are less completely controlled by the cationic environment than are the other functions investigated.

Numerical Approach for the Consideration of Hold Time Effects

2014 ◽  
Author(s):  
Sven H. Reese ◽  
Johannes Seichter ◽  
Dietmar Klucke ◽  
H. Ertugrul Karabaki ◽  
Wolfgang Mayinger
Keyword(s):  
Hold Time ◽  
Austenitic Steels ◽  
Normal Operation ◽  
Primary Circuit ◽  
Published Data ◽  
Fatigue Lifetime ◽  
Time Effects ◽  
Positive Effects ◽  
Surge Line ◽  
Circuit Components

In recent years the Environmentally Assisted Fatigue (EAF) became an item, which has to be considered additionally in terms of ensuring a conservative determination of the actual component’s health status resp. the CUF. For practical application, the consideration of the so called Fen-factor leads to the reduction of the admissible cycles in fatigue calculations. Beyond that the influence of elevated temperatures has been identified as one parameter having a negative influence on the admissible cycles as well. For example the German KTA 3201.2 defines for austenitic steels separate fatigue curves for temperatures above 80°C and for temperatures below 80°C. In summary on the one hand parameters influencing component’s lifetime negatively have to be considered in terms of conservative calculations. On the other hand, there are other parameters which influence the component’s fatigue lifetime in a positive manner. As such positive effects are neglected so far, CUF allowing for EAF tend to become over conservative leading to oversized components. Therefore, positive effects should be considered as well in the framework of a comprehensive and detailed analysis making sure not to overdesign components. When taking a closer look on the operational behavior of primary circuit components, fatigue loading is mainly defined by long steady-state periods with no significant changes in the loadings and by normally short outage periods with no thermal loading. For example fatigue of a PWR surge-line is mostly caused by short in-surge and out-surge events during start-up or shut-down of the plant. Normal operation transients mostly not cause fatigue relevant events in the surge-line. Fatigue of PWR spray-lines is primarily generated by very few spray-events during a one-year period of operation. Spray events are mainly caused by significant load ramps. Subsequently the fatigue status of primary circuit components is controlled by long periods with no fatigue relevant loading at operating temperature and few additional loading patterns in between. Experimental investigations have shown that hold time effects have a positive influence on fatigue lifetime of austenitic stainless steel materials. Anyhow, no quantification of these effects has been published in recent years. Within this publication an engineering based approach will be developed to quantify the hold time effect based on literature and published data. On the basis of a practical example the influence of hold time effects will be quantified and a direct comparison to lifetime reducing effect of EAF and temperature will be drawn.

Sch-28080 inhibits bafilomycin-sensitive H+ secretion in turtle bladder independently of luminal [K+]

1993 ◽  
Vol 265 (2) ◽  
pp. F174-F179
Author(s):  
O. F. Kohn ◽  
P. P. Mitchell ◽  
P. R. Steinmetz
Keyword(s):  
Competitive Inhibition ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Atpase Inhibitor ◽  
Turtle Bladder ◽  
High K ◽  
Ph Stat ◽  
Low Levels ◽  
K Concentration ◽  
Removal Studies

To explore the possible contribution of an H-K-adenosine-triphosphatase (H-K-ATPase) to H+ secretion (JH) in the isolated turtle bladder, we measured electrogenic JH (JeH) as short-circuit current and total JH (JTH) by pH stat titration in the presence of ouabain at different ambient K+ concentration ([K+]) and during luminal addition of a known gastric H-K-ATPase inhibitor, Schering (Sch)-28080. JH was not reduced by decreasing ambient [K+] to undetectable or very low levels (< 0.05 mM by atomic absorption) and luminal BaCl2 addition to further reduce local [K+] at the apical membrane. These K(+)-removal studies indicate that H+ transport is not coupled to countertransport of K+. JTH did not exceed JeH at any point: in K(+)-free solutions JTH was 0.73 +/- 0.05, and JeH was 0.95 +/- 0.08 mumol/h; in standard (3.5 mM) K+ solutions JTH was 0.72 +/- 0.05 and JeH 0.98 +/- 0.06 mumol/h; in high (118 mM) K+ solutions JTH was 0.65 +/- 0.07 and JeH 0.94 +/- 0.08 mumol/h. Sch-28080 caused a rapid inhibition of JH, with similar half-maximal inhibitory concentrations (IC50) in K(+)-free, standard [K+], and high [K+] solutions. Bafilomycin inhibited JeH and JTH with an IC50 of approximately 100 nM. The observed non-potassium-competitive inhibition of JH by Sch-28080 and the bafilomycin sensitivity distinguish the H-ATPase of the turtle bladder from the gastric H-K-ATPase. The rapidity of the inhibition by Sch-28080 suggests that it acts at an accessible luminal site of the ATPase.

scholarly journals Transcriptomic Analysis of Starch Biosynthesis in the Developing Grain of Hexaploid Wheat

2009 ◽  
Vol 2009 ◽  
pp. 1-23 ◽  
Author(s):  
Boryana S. Stamova ◽  
Debbie Laudencia-Chingcuanco ◽  
Diane M. Beckles
Keyword(s):  
Gene Expression ◽  
Dna Microarrays ◽  
Expression Profiles ◽  
Expression Patterns ◽  
Soluble Sugars ◽  
Starch Synthesis ◽  
Gene Families ◽  
Starch Accumulation ◽  
Protein Accumulation ◽  
High Accumulation

The expression of genes involved in starch synthesis in wheat was analyzed together with the accumulation profiles of soluble sugars, starch, protein, and starch granule distribution in developing caryopses obtained from the same biological materials used for profiling of gene expression using DNA microarrays. Multiple expression patterns were detected for the different starch biosynthetic gene isoforms, suggesting their relative importance through caryopsis development. Members of the ADP-glucose pyrophosphorylase, starch synthase, starch branching enzyme, and sucrose synthase gene families showed different expression profiles; expression of some members of these gene families coincided with a period of high accumulation of starch while others did not. A biphasic pattern was observed in the rates of starch and protein accumulation which paralleled changes in global gene expression. Metabolic and regulatory genes that show a pattern of expression similar to starch accumulation and granule size distribution were identified, suggesting their coinvolvement in these biological processes.

scholarly journals Vitamin K distribution in rat tissues: dietary phylloquinone is a source of tissue menaquinone-4

1994 ◽  
Vol 72 (3) ◽  
pp. 415-425 ◽  
Author(s):  
H. H. W. Thijssen ◽  
M. J. Drittij-Reijnders
Keyword(s):  
Salivary Gland ◽  
Tissue Distribution ◽  
Vitamin K ◽  
Mitochondrial Fraction ◽  
Rat Tissues ◽  
High K ◽  
Low Levels ◽  
Low K ◽  
The Brain ◽  
Tissue Vitamin

The present study was undertaken to determine whether there is selective tissue distribution of vitamin K in the rat and whether this distribution mirrors the distribution of tissue vitamin K metabolism. The effects of feeding a vitamin K-free diet followed by resupplementation with phylloquinone (K1) were studied. K1was recovered in all tissues. In K1-supplemented rats, most tissues accumulated K1relative to plasma K1with the highest levels in liver, heart, bone, and cartilaginous tissue (sternum). Low K1levels were found in the brain. In the K1-free rats, relatively high K1levels were still found in heart, pancreas, bone and sternum. Surprisingly, menaquinone-4 (MK-4) was detected in all tissues, with low levels in plasma and liver, and much higher levels in pancreas, salivary gland and sternum. MK-4 levels exceeded K1levels in brain, pancreas, salivary gland and sternum. Supplementation with K1, orally and by intravenous infusion, caused MK-4 levels to rise. Some accumulation of K1and MK-4 in the mitochondrial fraction was found for kidney, pancreas and salivary gland. In the liver the higher menaquinones (MK-6–9) accumulated in the mitochondria. The results indicate that: (1) there is selective tissue distribution of K1and MK-4, (2) dietary K1is a source of MK-4. The results also suggest there may be an as yet unrecognized physiological function for vitamin K (MK-4).

Frequency of leisure activities and depressive symptomatology in elderly people: the moderating role of rumination

2013 ◽  
Vol 26 (2) ◽  
pp. 297-305 ◽  
Author(s):  
Virginia Fernández-Fernández ◽  
María Márquez-González ◽  
Andrés Losada-Baltar ◽  
Rosa Romero-Moreno
Keyword(s):  
Elderly People ◽  
Emotional Regulation ◽  
Depressive Symptomatology ◽  
Leisure Activities ◽  
Hierarchical Regression ◽  
Positive Effects ◽  
Low Levels ◽  
Main Effects ◽  
Moderating Role

ABSTRACTBackground:The positive effects of leisure activities on depressive symptomatology are well known. However, the extent to which emotional regulation variables moderate that relationship has scarcely been studied, especially in older people. The aim of this study is to analyze the moderating role of rumination in the relation between leisure activities and depressive symptoms.Methods:Participants in this study were 311 people, aged 60 to 90 years (mean age: 71.27 years; SD: 6.99; 71.7% women). We evaluated depressive symptomatology, frequency of leisure activities, and rumination. We carried out a hierarchical regression analysis to confirm the moderating role of rumination.Results:We obtained a model that explains 39.4% of the variance of depressive symptomatology. Main effects were found for the frequency of leisure activities (β = −0.397; p < 0.01) and for rumination (β = 0.497; p < 0.01). Moreover, we found a significant effect of the interaction between frequency of leisure activities and rumination (β = 0.110; p < 0.05), suggesting that rumination plays a moderating role in the relation between leisure activities and depressive symptomatology.Conclusions:A risk profile of elderly people may consist of those who engage in low levels of leisure activities but also use more frequently the dysfunctional emotional regulation strategy of rumination.

Personality determinants of need for interaction with a retail employee and its impact on self-service technology (SST) usage intentions

2017 ◽  
Vol 11 (3) ◽  
pp. 214-231 ◽  
Author(s):  
Hyun-Joo Lee
Keyword(s):  
Structural Equation ◽  
Online Survey ◽  
Equation Modeling ◽  
Thinking Style ◽  
Content Type ◽  
Positive Effects ◽  
Negative Effect ◽  
Experiential Thinking ◽  
Low Levels ◽  
Self Service

Purpose The purpose of this study was, first, to link interpersonal-hedonic values, intuitive-experiential thinking style, external locus of control (LOC) and sociability to the need for interaction with a retail employee; and, second, to empirically test the moderating effect of the time convenience of self-service technologies (SSTs) on the proposed relationships in the model. Design/methodology/approach This study was conducted in a retail setting in which an automated checkout process occurred with the use of self-checkout systems. A self-administered, online survey approach was utilized targeting consumer panel members. Data were analyzed using structural equation modeling. Findings Interpersonal-hedonic values, external LOC and sociability emerged as reliable antecedents of the need for interaction with a retail employee, whereas the intuitive-experiential thinking style did not. This study also showed the inverse relationship between the need for interaction with a retail employee and the intentions to use SSTs. In relation to the moderating role of the time convenience of SSTs, the positive effects of interpersonal-hedonic values, intuitive-experiential thinking style, external LOC and sociability on the need for interaction with a retail employee were shown lesser for consumers with low levels of the time convenience of SSTs. The negative effect of the need for interaction with a retail employee on the intentions to use SSTs was shown to be greater for consumers with low levels of the time convenience of SSTs. Originality/value The present study adds to a growing body of literature on SSTs by exploring the causal and hierarchical effects of personality traits that determine the intentions to use SSTs.

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