Search results for "Depletion"
showing 10 items of 115 documents
Space charge effect on competitive ion transport through ion-exchange membranes
2002
A mathematical model of the competitive electro-transport of two counter-ions through an ion exchange membrane based on the Nernst-Planck and Poisson equations is developed. A three-layer system is considered: the membrane and two adjacent diffusion layers. Concentration profiles in the three layers, effective transport numbers as functions of the current and current-voltage characteristics are calculated. Deviation from the local electroneutrality in space charge region near the depleted solution/membrane interface is taken into account. It is shown that the space charge region grows with the voltage applied. However the fluxes of the competitive counter-ions at over-limiting currents are …
Irrigation water saving strategies in Citrus orchards: Analysis of the combined effects of timing and severity of soil water deficit
2021
[EN] The knowledge of the crop response to soil water deficit is essential to predict the actual crop water requirements under limited soil water conditions. The mathematical schematization of the crop response under RDI can allow identifying the exact irrigation timing. The threshold of soil water status below which crop transpiration decreases represents a key parameter for the water stress functions. The main objective of this paper was to investigate the effects of several RDI treatments, applied during the three stages of fruit growth, on soil-plant-water relations of drip-irrigated mandarin trees. Experiments were carried out in seven irrigation treatments: a control, irrigated at 125…
Local Time-Dependent Charging in a Perovskite Solar Cell
2016
Efficient charge extraction within solar cells explicitly depends on the optimization of the internal interfaces. Potential barriers, unbalanced charge extraction, and interfacial trap states can prevent cells from reaching high power conversion efficiencies. In the case of perovskite solar cells, slow processes happening on time scales of seconds cause hysteresis in the current-voltage characteristics. In this work, we localized and investigated these slow processes using frequency-modulation Kelvin probe force microscopy (FM-KPFM) on cross sections of planar methylammonium lead iodide (MAPI) perovskite solar cells. FM-KPFM can map the charge density distribution and its dynamics at intern…
Does work engagement physiologically deplete? Results from a daily diary study
2020
Based on the conservation of resources theory, we argue that work engagement involves resource investment, and therefore physiologically depletes resources. On this basis, we propose that work enga...
The Guilty Couch Potato: The Role of Ego Depletion in Reducing Recovery Through Media Use
2014
This article addresses ego depletion as a mechanism influencing media-based stress recovery processes. Using structural equation modeling, relationships between ego depletion, procrastination, guilt, enjoyment, vitality, and recovery experience were tested using data from an online survey (N = 471). Results suggest that ego depletion may increase the risk of negatively appraising the use of interactive (video games) and noninteractive (television) entertaining media as a form of procrastination. The resulting guilt is negatively related to the recovery experience associated with using entertainment. Therefore, ego-depleted individuals may benefit less from the psychological recovery potenti…
Resistance of natural killer T cell-deficient mice to systemic Shwartzman reaction.
2000
The generalized Shwartzman reaction in mice which had been primed and challenged with lipopolysaccharide (LPS) depends on interleukin (IL)-12-induced interferon (IFN)-gamma production at the priming stage. We examined the involvement in the priming mechanism of the unique population of Valpha14 natural killer T (NKT) cells because they promptly produce IFN-gamma after IL-12 stimulation. We report here that LPS- or IL-12-primed NKT cell genetically deficient mice were found to be resistant to LPS-elicited mortality. This outcome can be attributed to the reduction of IFN-gamma production, because injection of recombinant mouse IFN-gamma, but not injection of IL-12, effectively primed the NKT …
An anti-inflammatory role for V alpha 14 NK T cells in Mycobacterium bovis bacillus Calmette-Guérin-infected mice.
2003
Abstract The possible contribution of NKT cells to resistance to Mycobacterium tuberculosis infection remains unclear. In this paper we characterized the Vα14 NKT cell population following infection with Mycobacterium bovis bacillus Calmette-Guérin (BCG). BCG infection determined an early expansion of Vα14 NKT cells in liver, lungs, and spleen, which peaked on day 8 and was sustained until day 30. However, an NK1.1+ Vα14 NKT population preferentially producing IFN-γ predominated at an early stage (day 8), which was substituted by an NK1.1− population preferentially producing IL-4 at later stages (day 30). Despite the fact that Vα14 NKT cell-deficient mice eliminated BCG as did control mice…
Obesity-associated deficits in inhibitory control are phenocopied to mice through gut microbiota changes in one-carbon and aromatic amino acids metab…
2021
Gut: first published.
Metronomic cyclophosphamide induces regulatory T cells depletion and PSA‐specific T cells reactivation in patients with biochemical recurrent prostat…
2019
Biochemical recurrence (BCR) occurs in up to 40% of prostate cancer patients after prostatectomy. In our study, we performed an immune monitoring study in 20 prostate cancer patients with BCR previously treated with metronomic cyclophosphamide (mCTX). We observed a decrease of regulatory T cells (Tregs) from 2 months and this was more pronounced after 6 months of mCTX treatment. This drop of Tregs was associated with increased level of activated HLADR+ CD45R0+ T cells in peripheral blood. Furthermore, a reactivation of Th1 polarized anti-PSA T-cell response was detected in BCR patients treated with mCTX. However, dendritic cell subsets counts and activation were not influenced by the treatm…
Recovery of Varicella-Zoster Virus–Specific T Cell Immunity after T Cell–Depleted Allogeneic Transplantation Requires Symptomatic Virus Reactivation
2008
Abstract Reactivated varicella-zoster virus (VZV) infection causes herpes zoster and commonly occurs after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Because VZV-specific T cell immunity is essential to prevent virus reactivation, we developed an interferon-γ enzyme-linked immunosorbent spot (ELISPOT) assay for the sensitive detection of VZV-reactive T cells at the single-cell level ex vivo. We used this assay to monitor the frequency of VZV-reactive T cells in 17 seropositive patients during the first year after T cell–depleted allo-HSCT. The patients did not receive anti-herpesvirus prophylaxis after stem cell engraftment. Independent of the magnitude of transferred d…