scholarly journals Sleep spindle refractoriness segregates periods of memory reactivation

2017 ◽  
Author(s):  
James W. Antony ◽  
Luis Piloto ◽  
Margaret Wang ◽  
Paula Pacheco ◽  
Kenneth A. Norman ◽  
...  
Keyword(s):  
Refractory Period ◽  
Functional Role ◽  
Neural Mechanism ◽  
Initial Study ◽  
Sleep Spindles ◽  
Sleep Spindle ◽  
Memory Reactivation ◽  
The Stability

AbstractThe stability of long-term memories is enhanced by reactivation during sleep. Correlative evidence has linked memory reactivation with thalamocortical sleep spindles, although their functional role is poorly understood. Our initial study replicated this correlation but also demonstrated a novel rhythmicity to spindles, such that spindles are less likely to occur immediately following other spindles. We leveraged this rhythmicity to test the role of spindles in memory by using real-time spindle tracking to present cues inside versus outside the presumptive refractory period; as predicted, cues presented outside the refractory period led to better memory. Our findings reveal a previously undescribed neural mechanism whereby spindles segment sleep into two distinct substates: prime opportunities for reactivation and gaps that segregate reactivation events.One Sentence SummaryThe characteristic timing of sleep spindles regulates when memories can be reactivated during sleep.

scholarly journals The role of carbon-based materials in enhancing the stability of perovskite solar cells

2020 ◽  
Vol 13 (5) ◽  
pp. 1377-1407 ◽  
Author(s):  
Mahboubeh Hadadian ◽  
Jan-Henrik Smått ◽  
Juan-Pablo Correa-Baena
Keyword(s):  
Solar Cells ◽  
Perovskite Solar Cells ◽  
The Stability ◽  
Carbon Based

Enhancing the stability of perovskite solar cells is crucial to the deployment of this technology. Carbon-based materials are promising candidates for providing long-term stable perovskite solar cells suitable for commercialization.

Long-term changes in rumen fermentation in defaunated sheep

1991 ◽  
Vol 1991 ◽  
pp. 77-77
Author(s):  
P.P. Frumholtz ◽  
R.J. Wallace ◽  
C.J. Newbold ◽  
E.R. Ørskov
Keyword(s):  
Animal Species ◽  
Fish Meal ◽  
Jugular Vein ◽  
Rumen Fermentation ◽  
Bacteria And Fungi ◽  
One Year ◽  
The Stability ◽  
Ciliate Protozoa

The removal of ciliate protozoa, or defaunation, results in the establishment of a new ecosystem in the rumen, consisting only of bacteria and fungi. Although extensive research has been done on ciliate-free ruminants, the role of protozoa in the rumen still provokes considerable debate. The diversity of experimental design, such as animal species, defaunation method, and diet could account for many of the differences observed between defaunation studies. Also it is important to examine the stability of the ciliate-free ecosystem. The aim of this study was to investigate changes in rumen fermentation of ciliate-free sheep over a period of one year.Eight male castrated sheep, weighing 60-70 kg, received twice daily 700 g of a diet of hay, barley, molasses, fish meal and vitamins/minerals (500, 299.5, 100, 91 and 9.5 g/kg DM respectively). Four sheep were defaunated by the rumen washing technique (Jouany and Senaud, 1979) and kept in isolated pens while the other four were left faunated with a mixed type A ciliate protozoa population. Rumen samples were withdrawn via the rumen cannula and blood samples were taken from the jugular vein -1, 0, 1, 2, 4 and 6 h after feeding. There were three sampling periods: one month, six months and one year after defaunation.

scholarly journals Functional Role of Suppressor of Cytokine Signaling 3 Upregulation in Hypothalamic Leptin Resistance and Long-Term Energy Homeostasis

Diabetes ◽  
2010 ◽  
Vol 59 (4) ◽  
pp. 894-906 ◽  
Author(s):  
A. S. Reed ◽  
E. K. Unger ◽  
L. E. Olofsson ◽  
M. L. Piper ◽  
M. G. Myers ◽  
...  
Keyword(s):  
Functional Role ◽  
Energy Homeostasis ◽  
Leptin Resistance ◽  
Cytokine Signaling ◽  
Suppressor Of Cytokine Signaling ◽  
Term Energy

scholarly journals Brief targeted memory reactivation during the awake state enhances memory stability and benefits the weakest memories

2017 ◽  
Author(s):  
Arielle Tambini ◽  
Alice Berners-Lee ◽  
Lila Davachi
Keyword(s):  
Long Term Memory ◽  
Recent Experience ◽  
Memory Reactivation ◽  
Retrieval Processes ◽  
Initial Learning ◽  
Explicit Recognition ◽  
The Stability ◽  
Task Oriented ◽  
Or Task

ABSTRACTReactivation of representations corresponding to recent experience is thought to be a critical mechanism supporting long-term memory stabilization. Targeted memory reactivation, or the re-exposure of recently learned cues, seeks to induce reactivation and has been shown to benefit later memory when it takes place during sleep. However, despite recent evidence for endogenous reactivation during post-encoding awake periods, less work has addressed whether awake targeted memory reactivation modulates memory. Here, we found that brief (50ms) visual stimulus re-exposure during a repetitive foil task enhanced the stability of cued versus uncued associations in memory. The extent of external or task-oriented attention prior to re-exposure was inversely related to cueing benefits, suggesting that an internally-orientated state may be most permissible to reactivation. Critically, cueing-related memory benefits were greatest in participants without explicit recognition of cued items and remained reliable when only considering associations not recognized as cued, suggesting that explicit cue-triggered retrieval processes did not drive cueing benefits. Cueing benefits were strongest for items and participants with the poorest initial learning. These findings expand our knowledge of the conditions under which targeted memory reactivation can benefit memory, and in doing so, support the notion that reactivation during awake time periods improves memory stabilization.

scholarly journals IMPROVING INTER-BUDGETARY RELATIONS IN ORDER TO FORM AN EFFECTIVE REGIONAL BUDGET

2021 ◽  
Vol 10 (34) ◽  
Author(s):  
A.S OSTRONOSOVA ◽  
Keyword(s):  
Functional Role ◽  
Financial Resources ◽  
Economic Independence ◽  
Financial Independence ◽  
Regional Budget ◽  
The Subject ◽  
The Stability ◽  
Regional Budgets

Improving the efficiency of inter-budgetary relations is also a problem facing the budget of regions and municipalities. Work is underway in this area, but with this in mind, the problem of strengthening financial independence remains urgent. For this purpose, it is expected to increase the stability of budget legislation, which will allow you to put on a solid basis the planning of your own budget revenues and increase the functional role of funds formed within the framework of inter-budget relations. Improving the efficiency of inter-budgetary relations is also a problem facing the budget of regions and municipalities. Work is underway in this area, but with this in mind, the problem of strengthening financial independence remains urgent. For this purpose, it is expected to increase the stability of budget legislation, which will allow you to put on a solid basis the planning of your own budget revenues and increase the functional role of funds formed within the framework of inter-budget relations. The problem of the deficit of financing remains an acute problem of the regional budget, as a result of which the volume of needs is not covered by real financial resources for the budget. This is based on a methodologically erroneous approach to the formation of budget expenditures. In this regard, the relevance of the chosen topic is due to the fact that at present the most urgent issue is the lack of financial and economic independence of regions and the imbalance of local budgets. The purpose of the research is to suggest ways to improve the organization of inter-budgetary relations. The subject of the research is the peculiarities of the organization of inter-budgetary relations of regional budgets.

scholarly journals Rotating waves during human sleep spindles organize global patterns of activity that repeat precisely through the night

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Lyle Muller ◽  
Giovanni Piantoni ◽  
Dominik Koller ◽  
Sydney S Cash ◽  
Eric Halgren ◽  
...  
Keyword(s):  
Large Scale ◽  
Activity Patterns ◽  
Neural Mechanism ◽  
Sleep Spindles ◽  
Sleep Spindle ◽  
Spike Time ◽  
Temporal Precision ◽  
Global Patterns ◽  
Spike Time Dependent Plasticity ◽  
Large Scale Networks

During sleep, the thalamus generates a characteristic pattern of transient, 11-15 Hz sleep spindle oscillations, which synchronize the cortex through large-scale thalamocortical loops. Spindles have been increasingly demonstrated to be critical for sleep-dependent consolidation of memory, but the specific neural mechanism for this process remains unclear. We show here that cortical spindles are spatiotemporally organized into circular wave-like patterns, organizing neuronal activity over tens of milliseconds, within the timescale for storing memories in large-scale networks across the cortex via spike-time dependent plasticity. These circular patterns repeat over hours of sleep with millisecond temporal precision, allowing reinforcement of the activity patterns through hundreds of reverberations. These results provide a novel mechanistic account for how global sleep oscillations and synaptic plasticity could strengthen networks distributed across the cortex to store coherent and integrated memories.

scholarly journals A hippocampal model for behavioral time acquisition and fast bidirectional replay of spatio-temporal memory sequences

2018 ◽  
Author(s):  
Marcelo Matheus Gauy ◽  
Johannes Lengler ◽  
Hafsteinn Einarsson ◽  
Florian Meier ◽  
Felix Weissenberger ◽  
...  
Keyword(s):  
Functional Role ◽  
Long Term Memory ◽  
Temporal Memory ◽  
Synfire Chains ◽  
Dendritic Spikes ◽  
Spatio Temporal ◽  
Time Acquisition ◽  
Global Inhibition

AbstractThe hippocampus is known to play a crucial role in the formation of long-term memory. For this, fast replays of previously experienced activities during sleep or after reward experiences are believed to be crucial. But how such replays are generated is still completely unclear. In this paper we propose a possible mechanism for this: we present a model that can store experienced trajectories on a behavioral timescale after a single run, and can subsequently bidirectionally replay such trajectories, thereby omitting any specifics of the previous behavior like speed, etc, but allowing repetitions of events, even with different subsequent events. Our solution builds on well-known concepts, one-shot learning and synfire chains, enhancing them by additional mechanisms using global inhibition and disinhibition. For replays our approach relies on dendritic spikes and cholinergic modulation, as supported by experimental data. We also hypothesize a functional role of disinhibition as a pacemaker during behavioral time.

scholarly journals Cold fronts: probes of plasma astrophysics in galaxy clusters

2016 ◽  
Vol 82 (3) ◽  
Author(s):  
John A. ZuHone ◽  
E. Roediger
Keyword(s):  
Galaxy Clusters ◽  
Mean Free Path ◽  
Magnetized Plasma ◽  
X Ray ◽  
Gas Phases ◽  
Cold Fronts ◽  
The Mean ◽  
The Stability

The most massive baryonic component of galaxy clusters is the ‘intracluster medium’ (ICM), a diffuse, hot, weakly magnetized plasma that is most easily observed in the X-ray band. Despite being observed for decades, the macroscopic transport properties of the ICM are still not well constrained. A path to determine macroscopic ICM properties opened up with the discovery of ‘cold fronts’. These were observed as sharp discontinuities in surface brightness and temperature in the ICM, with the property that the denser side of the discontinuity is the colder one. The high spatial resolution of the Chandra X-ray Observatory revealed two puzzles about cold fronts. First, they should be subject to Kelvin–Helmholtz instabilities, yet in many cases they appear relatively smooth and undisturbed. Second, the width of the interface between the two gas phases is typically narrower than the mean free path of the particles in the plasma, indicating negligible thermal conduction. It was thus realized that these special characteristics of cold fronts may be used to probe the properties of the cluster plasma. In this review, we will discuss the recent simulations of cold fronts in galaxy clusters, focusing on those which have attempted to use these features to constrain ICM physics. In particular, we will examine the effects of magnetic fields, viscosity, and thermal conductivity on the stability properties and long-term evolution of cold fronts. We conclude with a discussion on what important questions remain unanswered, and the future role of simulations and the next generation of X-ray observatories.

scholarly journals The Bordetella Bps Polysaccharide Is Critical for Biofilm Development in the Mouse Respiratory Tract

2007 ◽  
Vol 189 (22) ◽  
pp. 8270-8276 ◽  
Author(s):  
Gina Parise Sloan ◽  
Cheraton F. Love ◽  
Neelima Sukumar ◽  
Meenu Mishra ◽  
Rajendar Deora
Keyword(s):  
Whooping Cough ◽  
Three Dimensional ◽  
Respiratory Pathogens ◽  
Adolescents And Adults ◽  
The Stability ◽  
Inert Surfaces ◽  
Biofilm Development

ABSTRACT Bordetellae are respiratory pathogens that infect both humans and animals. Bordetella bronchiseptica establishes asymptomatic and long-term to life-long infections of animal nasopharynges. While the human pathogen Bordetella pertussis is the etiological agent of the acute disease whooping cough in infants and young children, it is now being increasingly isolated from the nasopharynges of vaccinated adolescents and adults who sometimes show milder symptoms, such as prolonged cough illness. Although it has been shown that Bordetella can form biofilms in vitro, nothing is known about its biofilm mode of existence in mammalian hosts. Using indirect immunofluorescence and scanning electron microscopy, we examined nasal tissues from mice infected with B. bronchiseptica. Our results demonstrate that a wild-type strain formed robust biofilms that were adherent to the nasal epithelium and displayed architectural attributes characteristic of a number of bacterial biofilms formed on inert surfaces. We have previously shown that the Bordetella Bps polysaccharide encoded by the bpsABCD locus is critical for the stability and maintenance of three-dimensional structures of biofilms. We show here that Bps is essential for the formation of efficient nasal biofilms and is required for the colonization of the nose. Our results document a biofilm lifestyle for Bordetella in mammalian respiratory tracts and highlight the essential role of the Bps polysaccharide in this process and in persistence of the nares.

scholarly journals Long-term Marital Satisfaction: Couples’ Narratives of the Role of Mate Selection

2020 ◽  
Vol 6 (4) ◽  
pp. 267-276
Author(s):  
Maryam Jamalnik ◽  
◽  
Mohammad Reza Falsafinejad ◽  
Anahita Khodabakhshi-Koolaee ◽  
◽  
...  
Keyword(s):  
Marital Satisfaction ◽  
Mental Health Professionals ◽  
Mate Selection ◽  
Vital Role ◽  
Psychiatric Nurses ◽  
Traditional Societies ◽  
The Stability ◽  
Theoretical Saturation

Background: Long-term marital satisfaction depends on various factors in couples’ lives. Shared interests, beliefs, and goals can guarantee couples’ long and satisfying relationships. However, mate selection is one of the primary requirements for establishing a marital relationship in both modern and traditional societies. Based on the narratives of couples, the present study aimed to explore the role of mate selection in marital satisfaction. Methods: This study employed a qualitative narrative research design. The participants were couples who lived together at least for 10 years, were satisfied with their married life, and had children. They were selected through the purposive sampling method from the family entertainment centers of health houses affiliated with Qom Municipality, in 2019. The data were generated using in-depth in-person interviews. After interviewing 13 couples, theoretical saturation was obtained. The data were recorded, transcribed, and analyzed manually using the textual analytic approach. Results: The analysis of the participants’ narratives showed that the couples believed that four main themes, including spouse personality traits, shared religious beliefs, shared socioeconomic positions, and mutual respect and understanding affected their marital satisfaction. Conclusion: The couples who were satisfied with their marriage believed that realistic and correct mate selection played a vital role in the survival and stability of their marital life. It is very important to pay attention to the role and conditions of mate selection and its impact on the stability of marriage. Results from this study help counselors, couples’ therapists, mental health professionals, psychiatric nurses, and midwifery consultants prepare couples for premarital programs.

Sign in / Sign up

Export Citation Format

Share Document