The Relationship Between Light-induced Changes in Transpiration Pull and Rehydration Times in Desiccated Myrothamnus flabellifolia

2014 ◽  
Vol 48 (4) ◽  
pp. 423-428
Author(s):  
Zhu Jianjun ◽  
Liu Linde ◽  
Zhu Luying
Author(s):  
Angelica Mazzoletti ◽  
Domenico Albano ◽  
Francesco Bertagna ◽  
Claudio Tinoco Mesquita ◽  
Raffaele Giubbini

Abstract Background-Aim The relationship between perfusion pattern and stress-induced changes in Left Ventricular Mechanical Dyssynchrony (LVMD) has been previously described with controversial results using stress-rest perfusion imaging studies. The aim of this study was to assess the relationship between perfusion pattern and stress-induced changes in LVMD usingo regadenoson/rest13N-NH3 PET/CT. Methods There were 74 patients who underwent stress-rest 13N-NH PET/CT from January 2014 to October 2018 excluding patients with left bundle branch block, ventricular pacing and myocardial necrosis. The patients were divided into those with reversible perfusion defects at stress (Ischemic group, n = 18) and patients without reversible perfusion defects (non-ischemic group, n = 56). The LVMD parameters included: phase standard deviation (PSD) and phase histogram bandwidth (PHB), after stress and at rest. The ΔPSD (post-stressPSD-restPSD) and ΔPHB (post-stressPHB—restPHB) were calculated to measure stress-induced changes in LVMD. Results There were no significant differences in LVMD parameters between post-stress and at rest in both groups. The PSD post-stress, ΔPSD and PHB post-stress were significantly higher in the ischemic group. Conclusions Using a vasodilator as a stress, the PSD and PHB post-stress and ΔPSD were significantly higher in the ischemic patients than the non-ischemic group, while there were no significant differences in each cohort between stress and rest indices.


2020 ◽  
Vol 33 (15) ◽  
pp. 6297-6314 ◽  
Author(s):  
Aurélien Ribes ◽  
Soulivanh Thao ◽  
Julien Cattiaux

AbstractDescribing the relationship between a weather event and climate change—a science usually termed event attribution—involves quantifying the extent to which human influence has affected the frequency or the strength of an observed event. In this study we show how event attribution can be implemented through the application of nonstationary statistics to transient simulations, typically covering the 1850–2100 period. The use of existing CMIP-style simulations has many advantages, including their availability for a large range of coupled models and the fact that they are not conditional to a given oceanic state. We develop a technique for providing a multimodel synthesis, consistent with the uncertainty analysis of long-term changes. Last, we describe how model estimates can be combined with historical observations to provide a single diagnosis accounting for both sources of information. The potential of this new method is illustrated using the 2003 European heat wave and under a Gaussian assumption. Results suggest that (i) it is feasible to perform event attribution using transient simulations and nonstationary statistics, even for a single model; (ii) the use of multimodel synthesis in event attribution is highly desirable given the spread in single-model estimates; and (iii) merging models and observations substantially reduces uncertainties in human-induced changes. Investigating transient simulations also enables us to derive insightful diagnostics of how the targeted event will be affected by climate change in the future.


2012 ◽  
Vol 2012 ◽  
pp. 1-9
Author(s):  
Xing-Xing Liu ◽  
Chang-Bin Sun ◽  
Ting-Tong Yang ◽  
Da Li ◽  
Chun-Yan Li ◽  
...  

The skin, the body's largest organ, plays an important role in the biotransformation/detoxification and elimination of xenobiotics and endogenous toxic substances, but its role in oxidative stress and insulin resistance is unclear. We investigated the relationship between skin detoxification and oxidative stress/insulin resistance by examining burn-induced changes in nicotinamide degradation. Rats were divided into four groups: sham-operated, sham-nicotinamide, burn, and burn-nicotinamide. Rats received an intraperitoneal glucose injection (2 g/kg) with (sham-nicotinamide and burn-nicotinamide groups) or without (sham-operated and burn groups) coadministration of nicotinamide (100 mg/kg). The results showed that the mRNA of all detoxification-related enzymes tested was detected in sham-operated skin but not in burned skin. The clearance of nicotinamide andN1-methylnicotinamide in burned rats was significantly decreased compared with that in sham-operated rats. After glucose loading, burn group showed significantly higher plasma insulin levels with a lower muscle glycogen level than that of sham-operated and sham-nicotinamide groups, although there were no significant differences in blood glucose levels over time between groups. More profound changes in plasma H2O2and insulin levels were observed in burn-nicotinamide group. It may be concluded that decreased skin detoxification may increase the risk for oxidative stress and insulin resistance.


2016 ◽  
Vol 19 ◽  
Author(s):  
Anja Pahor ◽  
Norbert Jaušovec

AbstractA brief overview of structural and functional brain characteristics related to g is presented in the light of major neurobiological theories of intelligence: Neural Efficiency, P-FIT and Multiple-Demand system. These theories provide a framework to discuss the main objective of the paper: what is the relationship between individual alpha frequency (IAF) and g? Three studies were conducted in order to investigate this relationship: two correlational studies and a third study in which we experimentally induced changes in IAF by means of transcranial alternating current stimulation (tACS). (1) In a large scale study (n = 417), no significant correlations between IAF and IQ were observed. However, in males IAF positively correlated with mental rotation and shape manipulation and with an attentional focus on detail. (2) The second study showed sex-specific correlations between IAF (obtained during task performance) and scope of attention in males and between IAF and reaction time in females. (3) In the third study, individuals’ IAF was increased with tACS. The induced changes in IAF had a disrupting effect on male performance on Raven’s matrices, whereas a mild positive effect was observed for females. Neuro-electric activity after verum tACS showed increased desynchronization in the upper alpha band and dissociation between fronto-parietal and right temporal brain areas during performance on Raven’s matrices. The results are discussed in the light of gender differences in brain structure and activity.


2009 ◽  
Vol 55 (No. 2) ◽  
pp. 51-57 ◽  
Author(s):  
H.Y. Dasgan ◽  
S. Kusvuran ◽  
K. Abak ◽  
L. Leport ◽  
F. Larher ◽  
...  

Citrulline has been recently shown to behave as a novel compatible solute in the <i>Citrullus lanatus</i> (<i>Cucurbitaceae</i>) growing under desert conditions. In the present study we have investigated some aspects of the relationship which might occur in leaves of melon seedlings, also known to produce citrulline, between the capacity to accumulate this ureido amino acid and salt tolerance. With this end in view, salt-induced changes at the citrulline level have been compared in two melon genotypes exhibiting contrasted abilities to withstand the damaging effects of high salinity. Progressive salinization of the growing solution occurred at 23 days after sowing. The final 250 mmol/l external NaCl concentration was reached within 5 days and further maintained for 16 days. In response to this treatment, it was found that the citrulline amount increased in fully expanded leaves of both genotypes according to different kinetics. The salt tolerant genotype Midyat was induced to accumulate citrulline 4 days before the salt sensitive Yuva and as a consequence the final amount of this amino acid was twice higher in the former than in the latter. Compared with citrulline, the free proline level was found to be relatively low and the changes induced in response to the salt treatment exhibited different trends according to the genotypes under study. Thus at the end of the treatment mature leaves of the salt sensitive Yuva contained higher amount of proline than those of Midyat. The changes in the calculated molar ratio between citrulline and free proline suggested that salt tolerance might be associated with high values for this ratio and vice et versa for sensitivity. The interest of citrulline as a biochemical marker for salt tolerance of melon genotypes is discussed.


1987 ◽  
Vol 252 (3) ◽  
pp. G365-G373 ◽  
Author(s):  
W. D. Barber ◽  
G. D. Stevenson ◽  
T. F. Burks

The gastric motor or mechanical effects of a group of peptides, the tachykinins, were evaluated in anesthetized cats to determine the relationship between local motor events and brain stem neurons that regulate gastric activity. The peptides evaluated were substance P, physalaemin, and eledoisin. The tachykinin-induced gastric changes were dose related and were characterized by initial distention-sustained contraction-late distention phases. At lower doses distention was the dominant effect with a sustained contraction-late distention response appearing as the dose increased. The sustained contraction-late distention phases were frequently accompanied by phasic contractions with a frequency of 2-4/min. Atropine had a significant effect on the sustained contraction phase but no effect on the phasic contractions or distention phases. Bilateral cervical vagotomy had a significant effect on the early distention phase, suggesting a link with brain stem mechanisms. The activity of brain stem units that responded to phasic distention of the stomach reflected the tachykinin-induced changes in gastric distention. Although the gastric effects of these tachykinins shared distinct similarities, certain differences in the time sequence of the distention-contraction interactions suggests the possibility that dissimilar receptor types may be involved in the mechanisms of action. Their mechanisms of action may also involve a direct effect on the effector organ.


1998 ◽  
Vol 66 (2) ◽  
pp. 397-402 ◽  
Author(s):  
S. M. Rhind ◽  
H. W. Reid ◽  
S. R. McMillen ◽  
G. Palmarini

AbstractThe relationship between weaning stress-induced changes in stress hormone profiles and immune function was investigated in groups of 10 lambs immunized against adrenocorticotrophic hormone (ACTH; treatment A) or fi-endorphin (treatment B) to reduce the circulating concentrations of cortisol and fi-endorphin respectively. Control animals (treatment C) were immunized against a porcine thyroglobulin carrier protein. Application of weaning stress was associated with significantly elevated plasma cortisol concentrations but no significant increase in fi-endorphin concentrations in C lambs. Immunization against ACTH suppressed the post-weaning increase in cortisol concentration. This was associated with a transient reduction in the lymphocyte stimulation response to keyhole limpet haemocyanin (KLH) antigen in the A animals but there was no effect on the antibody response or interferon-y production by antigen stimulated lymphocytes. There were no significant effects of immunization against fi-endorphin on the capacity to mount antibody or cell-mediated immune responses. It is concluded that weaning stress-induced increases in cortisol did not inhibit the immune response. Since cortisol concentrations and the cell mediated immune response at 8 days after immunization were positively associated it is concluded that these indices are not independent measures of stress.


1999 ◽  
Vol 66 (3) ◽  
pp. 680-686 ◽  
Author(s):  
C. Barret ◽  
S. Baste

This paper is concerned with the relationship between the effective stiffness tensor and the intensity of damage in individual modes for an anisotropic material with tilted cracks. The predictions are compared favorably with the experimentally measured load-induced changes of the 13 stiffnesses of a two-dimensional C/C-SiC ceramic matrix composite subjected to an off-axis solicitation. By taking into account the thickness of the cracks, it is possible to understand the change of the elastic anisotropy of the material and of its inelastic strain.


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