Role of Equatorial Fountain for the Delayed Response of Thermosphere O 1 D 630.0 nm Dayglow Over the Dip Equator During an X‐Class Flare

2021 ◽  
Vol 126 (2) ◽  
Author(s):  
C. Vineeth ◽  
K. M. Ambili ◽  
T. K. Pant ◽  
K. V. Subrahmanyam
Keyword(s):  
Delayed Response ◽  
Dip Equator ◽  
Class Flare

Dissociation in plasma renin and adrenal ANG II and aldosterone responses to sodium restriction in rats

1991 ◽  
Vol 261 (4) ◽  
pp. E487-E494 ◽  
Author(s):  
A. Menachery ◽  
L. M. Braley ◽  
I. Kifor ◽  
R. Gleason ◽  
G. H. Williams
Keyword(s):  
Plasma Renin ◽  
Fold Increase ◽  
Plasma Aldosterone ◽  
Delayed Response ◽  
Ang Ii ◽  
Sodium Restriction ◽  
Sodium Depletion ◽  
Pathway Activity

In rats, plasma renin activity (PRA) increases sharply, reaching a plateau within hours of sodium restriction. Plasma aldosterone increases gradually, not reaching a plateau for 1-2 days. To determine whether this dissociation is secondary to the time needed to modify adrenal sensitivity to angiotensin II (ANG II) and to assess the role of locally produced ANG II in this process, rats were salt restricted for 0-120 h. Plasma hormone levels were assessed, adrenal ANG II was measured, and basal and ANG II (1 x 10(-8) M)-stimulated steroidogenesis were determined in vitro. Although PRA attained an elevated plateau within 8 h, plasma aldosterone did not peak until after 48 h of sodium depletion. The in vitro aldosterone sensitivity to exogenous ANG II was not apparent until rats had been salt restricted for 16 h. A plateau (4-fold increase above the ANG II response on high salt) was achieved between 24 and 48 h. Adrenal ANG II also exhibited a similar delayed response that correlates significantly with changes in aldosterone biosynthesis and late pathway activity. Thus the dissociation between PRA and plasma aldosterone may be secondary to a lag in the zona glomerulosa's (ZG) steroidogenic response to ANG II as well as a parallel lag in tissue ANG II production, suggesting that changes in tissue ANG II may mediate ZG sensitivity to ANG II during sodium deprivation.

The role of D1-dopamine receptor in working memory: local injections of dopamine antagonists into the prefrontal cortex of rhesus monkeys performing an oculomotor delayed-response task

1994 ◽  
Vol 71 (2) ◽  
pp. 515-528 ◽  
Author(s):  
T. Sawaguchi ◽  
P. S. Goldman-Rakic
Keyword(s):  
Working Memory ◽  
Prefrontal Cortex ◽  
Injection Site ◽  
Target Location ◽  
Dopamine Antagonists ◽  
Dopamine Antagonist ◽  
Delayed Response ◽  
Intracerebral Injection ◽  
Control Task

1. To examine the role of dopamine receptors in the prefrontal cortex (PFC) on working memory, we injected dopamine antagonists (SCH23390, SCH39166, haloperidol, sulpiride, and raclopride) locally into the dorsolateral PFC in two monkeys trained to perform an oculomotor delayed-response (ODR) task. In the ODR task, monkeys fixate a central spot on a cathode ray tube (CRT) monitor while a visual cue is briefly (300 ms) presented in one of several peripheral locations in the visual field. After a delay of 1.5-6 s, the fixation spot is turned off, instructing the monkey to move its eyes to the target location that had been indicated by the visuospatial cue before the delay. Each monkey also performed a control task in which the cue remained on during the delay period. In this task the monkey's response was sensory rather than memory guided. 2. Local intracerebral injection of the selective dopamine antagonists SCH23390 (10-80 micrograms) and SCH39166 (1-5 micrograms) and/or the nonselective dopamine antagonist haloperidol (10-100 micrograms) induced deficits in ODR task performance at a total of 22 sites in the dorsolateral PFC. The deficit was characterized by a decrease in the accuracy of the memory-guided saccade as well as an increase in the latency of the response. The deficit usually appeared within 1-3 min after the injection, reached a peak at 20-40 min, and recovered at 60-90 min. 3. Performance change was restricted to a few specific target locations, which varied with the injection site and were most often contralateral to the injection site. 4. The degree of impairment in the ODR task occasioned by the injection of the dopamine antagonists was sensitive to the duration of delay; longer delays were associated with larger decreases in the accuracy and delayed onset of the memory-guided saccade. 5. The deficit was dose dependent; higher doses induced larger errors and increases in the onset of the memory-guided saccade. 6. Dopamine antagonists did not affect performance on the control task, which required the same eye movements but was sensory guided. Thus, in the same experimental session in which ODR performance was impaired, the accuracy and the latency of the sensory-guided saccades were normal for every target location.(ABSTRACT TRUNCATED AT 400 WORDS)

A Crisis of Legitimacy for the UN Collective Security System?

2007 ◽  
Vol 56 (1) ◽  
pp. 157-170 ◽  
Author(s):  
Christine Gray
Keyword(s):  
Security Council ◽  
Security System ◽  
Delayed Response ◽  
Collective Security ◽  
Institutional Failure ◽  
National Security Strategy ◽  
The Us ◽  
The Usa ◽  
Iraqi Freedom

The role of the UN and the legitimacy of its collective security system have been seriously challenged in recent years. First, because of the Security Council.s failure to act in cases of genocide or other humanitarian disaster. There has been much criticism of the limited and delayed response of the Security Council to events in Bosnia-Herzegovina and Rwanda, somewhat unfairly in so far as it was the lack of political will on the part of the Member States rather than any institutional failure that was responsible for the failure to act. Secondly, the UN's central role in collective security has been undermined by unilateral use of force by States. After the terrorist attacks of 11 September 2001 the UN was sidelined with regard to the forcible response against Afghanistan: in Operation Enduring Freedom the USA preferred not to act through the UN or even through NATO. Subsequently, the US National Security Strategy (September 2002) famously made no mention of the UN as a means of addressing perceived new threats from global terrorists. Most seriously, the US Operation Iraqi Freedom in 2003 was undertaken unilaterally, that is, without express Security Council authorization.1 This was often portrayed as a crisis of legitimacy for the UN as much as for the USA and the States which participated in the invasion. As the Deputy Secretary-General put it recently:

From theory to practice: The contribution of John Farquhar Fulton (1899–1960) to psychosurgery

2017 ◽  
Vol 41 (S1) ◽  
pp. S374-S375
Author(s):  
P. Michielsen ◽  
L. De Jonge ◽  
S. Petrykiv ◽  
M. Arts
Keyword(s):  
Frontal Lobe ◽  
Limbic System ◽  
Human Subjects ◽  
Animal Experiments ◽  
Delayed Response ◽  
Scientific Papers ◽  
Show Evidence ◽  
Correct Location ◽  
Competing Interest

IntroductionJohn Farquhar Fulton was an American neurophysiologist and historian, who pioneered psychosurgery based on animal experiments. Together with psychologist Carlyle Jacobsen, Fulton presented the results of bilateral frontal lobe ablation in chimpanzees. This study prompted neurologist Egas Moniz and neurologist Walter Freeman to perform similar brain surgery on human subjects.ObjectivesTo present the scientific papers of John Farquhar Fulton on psychosurgery.AimsTo review available literature and to show evidence that John Farquhar Fulton made a significant contribution to the development of psychosurgery.MethodsA biography and research papers are presented and discussed.ResultsFulton and Jacobsen experimented with ‘delayed response tasks’ in chimpanzees. The aim was to test the animal's capability to memorize the correct location of the food. They found that after sequential ablations of the left and right frontal association cortices these memory tasks became significantly difficult for the monkeys to perform. The researchers saw parallel conclusions in clinical cases of human frontal lobe damage.ConclusionsAn investigation into the role of the limbic system is one of the crowning achievements of John Farquhar Fulton, as this has influenced even today's thinking about the role of the limbic system. We should thank Fulton for his pioneering work as modern psychosurgery has gradually evolved from irreversible ablation to reversible stimulation techniques, including deep brain stimulation.Disclosure of interestThe authors have not supplied their declaration of competing interest.

scholarly journals «They’re not My Kind…» Anna Akhmatova and Natalia Krandievskaya

2019 ◽  
Vol 14 (2) ◽  
pp. 41-55
Author(s):  
Olga E. Rubinchik
Keyword(s):  
Strong Sense ◽  
Delayed Response ◽  
Open Letter ◽  
Political Role ◽  
Literary Life ◽  
Soviet Russia ◽  
Anna Akhmatova

N. V. Krandievskaya (1888–1963; her last name became Tolstaya after her second marriage with a writer А. N. Tolstoy) was a Russian poet, the author of three books of verse published during her life (1913, 1919, 1922), an outstanding collection of poems dedicated to the Siege of Leningrad (now St Petersburg) and a memoir. The article is dedicated to one of the longstanding poetical conversations between Natalia Krandievskaya and Anna Akhmatova. In July 1922 Akhmatova wrote a poem “They’re not my kind who left the land / To enemies and plundering...”. The poem can be called a “late reply” or “delayed response” to Krandievskaya, and an “urgent answer” to other addressees, among whom there was Aleksey Tolstoy first of all. A 1913 collection of poems by Krandievskaya includes the following one: “They’re not my kind who meet the life, / As like a dream...”. In this poem, the author speaks about her creative independence from two mainstreams in literature of that time: an emerging acmeism and a seasoned symbolism. Being an acmeist, Akhmatova treated the poem with a strong sense of offence. Besides, criticism of 1910 contributed to the origin of the rivalry between these two young poets. From summer 1918 until summer 1923, Krandievskaya stayed out of Soviet Russia with Tolstoy and their children, from October 1921 they were in Germany. When the publishing of the “Nakanune” newspaper, which actively advocated for coming back to Soviet Russia, started in March 1922 in Berlin, Tolstoy headed its literature department, and then he became an editor of its Sunday supplement. Two poems by Akhmatova were published on the first page of the first newspaper’s supplement on April 30. In response, an open letter by Akhmatova was published on August 1, 1922 in the “Notes on Literary Life” in Petrograd magazine, in which she spoke out against the publication of her poems without her knowledge and consent. The reason was an improper political role of the “Nakanune” newspaper and some Tolstoy’s misdeeds. Thus, the verse “I will not give them my poems” in the poem published in July 1922 and the answer of Akhmatova to the “Nakanune” newspaper in the “Notes on Literary Life” are directly interrelated. The similarity of the verse by Akhmatova with the poem by Krandievskaya suggests that the head of the arrow was aimed at the Tolstoy – Krandievskaya partnership first of all. However, the text by Akhmatova has many more addressees, and its meaning spreads far beyond the boundaries of a simple war of words. It’s “a poetic declaration on behalf of those who decided to stay, not evading a single blow” (R. Timenchick).

scholarly journals WASP-interacting Protein Is Important for Actin Filament Elongation and Prompt Pseudopod Formation in Response to a Dynamic Chemoattractant Gradient

2006 ◽  
Vol 17 (10) ◽  
pp. 4564-4575 ◽  
Author(s):  
Scott A. Myers ◽  
Laura R. Leeper ◽  
Chang Y. Chung
Keyword(s):  
Actin Polymerization ◽  
Time Course ◽  
Leading Edge ◽  
Delayed Response ◽  
Dependent Manner ◽  
Actin Assembly ◽  
Interacting Protein

The role of WASP-interacting protein (WIP) in the process of F-actin assembly during chemotaxis of Dictyostelium was examined. Mutations of the WH1 domain of WASP led to a reduction in binding to WIPa, a newly identified homolog of mammalian WIP, a reduction of F-actin polymerization at the leading edge, and a reduction in chemotactic efficiency. WIPa localizes to sites of new pseudopod protrusion and colocalizes with WASP at the leading edge. WIPa increases F-actin elongation in vivo and in vitro in a WASP-dependent manner. WIPa translocates to the cortical membrane upon uniform cAMP stimulation in a time course that parallels F-actin polymerization. WIPa-overexpressing cells exhibit multiple microspike formation and defects in chemotactic efficiency due to frequent changes of direction. Reduced expression of WIPa by expressing a hairpin WIPa (hp WIPa) construct resulted in more polarized cells that exhibit a delayed response to a new chemoattractant source due to delayed extension of pseudopod toward the new gradient. These results suggest that WIPa is required for new pseudopod protrusion and prompt reorientation of cells toward a new gradient by initiating localized bursts of actin polymerization and/or elongation.

scholarly journals The Prefrontal Cortex and Oculomotor Delayed Response: A Reconsideration of the “Mnemonic Scotoma”

2012 ◽  
Vol 24 (3) ◽  
pp. 627-635 ◽  
Author(s):  
Satoshi Tsujimoto ◽  
Bradley R. Postle
Keyword(s):  
Prefrontal Cortex ◽  
Target Location ◽  
Delayed Response ◽  
Short Term ◽  
Neuroscience Research ◽  
Analysis Window ◽  
Corrective Saccade ◽  
Response Task ◽  
Monkey Prefrontal Cortex

The concept of the “mnemonic scotoma,” a spatially circumscribed region of working memory impairment produced by unilateral lesions of the PFC, is central to the view that PFC is critical for the short-term retention of information. Presented here, however, are previously unpublished data that offer an alternative, nonmnemonic interpretation of this pattern of deficit. In their study, Wajima and Sawaguchi [Wajima, K., & Sawaguchi, T. The role of GABAergic inhibiton in suppressing perseverative responses in the monkey prefrontal cortex. Neuroscience Research, 50(Suppl. 1), P3–P317, 2004] applied the GABAA antagonist bicuculline methiodide unilaterally to the PFC of two monkeys while they performed an oculomotor delayed-response task. Consistent with previous studies, errors for the initial memory-guided saccade were markedly higher when the cued location fell into the region of the visual field affected by the infusion. These erroneous saccades tended to select an alternative target location (out of a possible 16) that had not been cued on that trial. By extending the analysis window, however, it was observed that the second, “corrective” saccade often acquired the location that had been cued on that trial. Further analysis of the erroneous initial saccades indicated that they tended to be directed to a location that had been relevant on the previous trial. Thus, the deficit was not one of “forgetting” the cued location. Rather, it was one of selecting between currently and previously relevant locations. These findings suggest a need for a reconsideration of the concept of the mnemonic scotoma, which in turn invites a reconsideration of functional interpretations of sustained neuronal activity in PFC.

scholarly journals ABA signalling and metabolism are not essential for dark-induced stomatal closure but affect response speed

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ashley J. Pridgeon ◽  
Alistair M. Hetherington
Keyword(s):  
Metabolic Pathways ◽  
Stomatal Closure ◽  
Response Speed ◽  
Signalling Pathways ◽  
Delayed Response ◽  
Wild Type ◽  
Receptor Mutant ◽  
Stomatal Movements ◽  
Molecular Patterns

AbstractStomata are microscopic pores that open and close, acting to balance CO2 uptake with water loss. Stomata close in response to various signals including the drought hormone abscisic acid (ABA), microbe-associated-molecular-patterns, high CO2 levels, and darkness. The signalling pathways underlying ABA-induced stomatal closure are well known, however, the mechanism for dark-induced stomatal closure is less clear. ABA signalling has been suggested to play a role in dark-induced stomatal closure, but it is unclear how this occurs. Here we investigate the role of ABA in promoting dark-induced stomatal closure. Tracking stomatal movements on the surface of leaf discs we find, although steady state stomatal apertures are affected by mutations in ABA signalling and metabolism genes, all mutants investigated close in response to darkness. However, we observed a delayed response to darkness for certain ABA signalling and metabolism mutants. Investigating this further in the quadruple ABA receptor mutant (pyr1pyl1pyl2pyl4), compared with wild-type, we found reduced stomatal conductance kinetics. Although our results suggest a non-essential role for ABA in dark-induced stomatal closure, we show that ABA modulates the speed of the dark-induced closure response. These results highlight the role of ABA signalling and metabolic pathways as potential targets for enhancing stomatal movement kinetics.

Sign in / Sign up

Export Citation Format

Share Document