Intrinsic Clocks

Intrinsic Clocks PDF Author: Timo Partonen
Publisher: Frontiers Media SA
ISBN: 2889454517
Category :
Languages : en
Pages : 117

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Book Description
"Intrinsic Clocks" presents an array of current research activities on intrinsic clocks and their contributions to biology and physiology. It elucidates the current models for the intrinsic clocks, their molecular components and key mechanisms as well as the key brain regions and animal models for their behavioral analysis. It provides a timely view on how these clocks guide behavior, and how their disruption may cause depressive-like behavior and impairment in cognitive functions. Thereby, any specific method by which the mood-related functions of the intrinsic clocks might be influenced bears therapeutic potential and has clinical interest. The importance of some of these mechanisms was highlighted by the 2017 award of the Nobel Prize in Physiology or Medicine to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for their discoveries of the genetic control of the daily biological rhythm. The key to the explanation was the discovery of transcription-translation feedback loops of the so-called “clock genes.”

Intrinsic Clocks

Intrinsic Clocks PDF Author: Timo Partonen
Publisher: Frontiers Media SA
ISBN: 2889454517
Category :
Languages : en
Pages : 117

Get Book

Book Description
"Intrinsic Clocks" presents an array of current research activities on intrinsic clocks and their contributions to biology and physiology. It elucidates the current models for the intrinsic clocks, their molecular components and key mechanisms as well as the key brain regions and animal models for their behavioral analysis. It provides a timely view on how these clocks guide behavior, and how their disruption may cause depressive-like behavior and impairment in cognitive functions. Thereby, any specific method by which the mood-related functions of the intrinsic clocks might be influenced bears therapeutic potential and has clinical interest. The importance of some of these mechanisms was highlighted by the 2017 award of the Nobel Prize in Physiology or Medicine to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for their discoveries of the genetic control of the daily biological rhythm. The key to the explanation was the discovery of transcription-translation feedback loops of the so-called “clock genes.”

Intrinsic Clocks

Intrinsic Clocks PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
"Intrinsic Clocks" presents an array of current research activities on intrinsic clocks and their contributions to biology and physiology. It elucidates the current models for the intrinsic clocks, their molecular components and key mechanisms as well as the key brain regions and animal models for their behavioral analysis. It provides a timely view on how these clocks guide behavior, and how their disruption may cause depressive-like behavior and impairment in cognitive functions. Thereby, any specific method by which the mood-related functions of the intrinsic clocks might be influenced bears therapeutic potential and has clinical interest. The importance of some of these mechanisms was highlighted by the 2017 award of the Nobel Prize in Physiology or Medicine to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for their discoveries of the genetic control of the daily biological rhythm. The key to the explanation was the discovery of transcription-translation feedback loops of the so-called "clock genes."

Insect Clocks

Insect Clocks PDF Author: D. S. Saunders
Publisher: Elsevier
ISBN: 1483182185
Category : Science
Languages : en
Pages : 288

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Book Description
Insect Clocks is mainly concerned with the phenomena in which ""environmental time"" has a practical implication for the life of insects for them to perform behavioral or physiological episodes at the ""right time"" and season. This text first discusses the concept of rhythms and clocks, along with the seasonal changes in the environment that affect a particular group of organisms. This book then explains circadian rhythms of insects. Photoperiodism and seasonal cycles of development; photoperiodic response, clock, and counter; and other types of insect clock are also tackled. This text concludes by explaining the anatomical location of photoreceptors and clocks. This publication will be invaluable to those interested in studying insects and their development affected by circles of influences.

Circadian Clocks

Circadian Clocks PDF Author: Achim Kramer
Publisher: Springer Science & Business Media
ISBN: 3642259502
Category : Medical
Languages : en
Pages : 414

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Book Description
This book provides the reader with a contemporary and comprehensive overview about the molecular, cellular and system-wide principles of circadian clock regulation. Emphasis is placed on the importance of circadian clocks for the timing of therapeutic interventions.

Remodeling of cardiac passive electrical properties and susceptibility to ventricular and atrial arrhythmias

Remodeling of cardiac passive electrical properties and susceptibility to ventricular and atrial arrhythmias PDF Author: George E. Billman
Publisher: Frontiers Media SA
ISBN: 288919647X
Category : Electronic book
Languages : en
Pages : 143

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Book Description
The effective management of cardiac arrhythmias, either of atrial or of ventricular origin, remains a major challenge. Sudden cardiac death due to ventricular tachyarrhythmias remains the leading cause of death in industrialized countries while atrial fibrillation is the most common rhythm disorder; an arrhythmia that’s prevalence is increasing and accounts for nearly one quarter of ischemic stokes the elderly population. Yet, despite the enormity of the problem, effective therapeutic interventions remain elusive. In fact, several initially promising antiarrhythmic agents were found to increase rather than decrease mortality in patients recovering from myocardial infarction. The question then is what went wrong, why have these interventions proven to be so ineffective? An obvious answer is the drugs were designed to attack the wrong therapeutic target. Clearly, targeting single ion channels (using either isolated ion channels or single myocytes preparations) has proven to be less than effective. What then is the appropriate target? It is well established that cardiac electrical properties can vary substantially between single cells and intact preparations. One obvious example is the observation that action potential duration is much longer in isolated cells as compared to multi-cellular preparations or intact hearts. Due to the low electrical resistance between adjacent myocytes, the cells act in coordinated fashion producing “electrotonic interdependence” between neighboring cells. Myocardial infarction and/or acute ischemia provoke profound changes in the passive electrical properties of cardiac muscle. In particular, electrotonic uncoupling of the myocytes disrupts the coordinated activation and repolarization of cardiac tissue. The resulting compensatory changes in ionic currents decrease cardiac electrical stability increasing the risk for life-threatening changes in the cardiac rhythm. Thus, the electrical properties of myocardial cells must be considered as a unit rather than in isolation. It is the purpose of this Research Topic to evaluate the largely neglected relationship between changes in passive electrical properties of cardiac muscle and arrhythmia formation.

VCSELs for Cesium-Based Miniaturized Atomic Clocks

VCSELs for Cesium-Based Miniaturized Atomic Clocks PDF Author: Ahmed Al-Samaneh
Publisher: BoD – Books on Demand
ISBN: 3738613668
Category : Technology & Engineering
Languages : en
Pages : 218

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Book Description
Frequency standards or clocks provide time references for a wide range of applications such as synchronization of communication networks, remote sensing and global positioning. Over the last couple of decades, demands on the data rates of many communication systems have substantially increased, imposing more restricted requirements on the stability of their timing devices. At the same time applications have become more mobile, increasing the demand for small and low-power clocks. Atomic clocks have provided the most stable frequency references for more than 50 years. However, the size and power requirements of microwave-cavity-based atomic clocks prohibit them from being portable and battery-operated. Hence, research on miniaturized atomic clocks (MACs) has been initiated by various research groups. A European research project on MACs, funded by the European commission started in 2008. This dissertation reports on the achievements within the European research project in the development of suitable lasers for such atomic clocks. Vertical-cavity surface-emitting lasers (VCSELs) are compelling light sources for MACs because of their low power consumption, high modulation bandwidth, and favorable beam characteristics. VCSELs must feature polarization-stable single-mode emission. Additionally, they must provide narrow linewidth emission at a center wavelength of about 894.6nm and be well suited for harmonic modulation at about 4.6GHz in order to employ coherent population trapping effect at the cesium D1 line. The polarization orientation of the emitted light of a standard VCSEL is a priori unknown. Polarization control is achieved by etching a shallow surface grating in the top Bragg mirror. For the purpose of integration with the clock microsystem, flip-chip-bondable VCSEL designs are realized. Such designs facilitate a straightforward mounting and make the electrical contacts high-frequency compatible.

Sleep and Clocks in Aging and Longevity

Sleep and Clocks in Aging and Longevity PDF Author: Anita Jagota
Publisher: Springer Nature
ISBN: 303122468X
Category : Family & Relationships
Languages : en
Pages : 553

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Book Description
This edited volume focuses on the interplay between sleep and circadian rhythms with health, aging and longevity. Sleep is absolutely important for human health and survival, as insufficient sleep is associated with a plethora of conditions, including the poor quality of life, onset of several diseases, and premature death. The sleep–wake cycle is an evolutionary conserved neurobiological phenomenon, and is a prominent manifestation of the biological clocks localised in the suprachiasmatic nucleus (SCN). Understanding bidirectional relationship between sleep and circadian rhythms is of utmost importance and urgency, especially in the context of modern lifestyle where sleep is often out of phase with the internal body clocks, social jetlag, artificial lights and so on. The 25 chapters by leading researchers and experts from 11 countries are arranged into seven sections: understanding sleep and clock interlink in health and longevity; sleep, aging and longevity; clock, aging and longevity; melatonin, sleep and clock; genetic regulation of sleep and clock; therapeutic interventions in sleep disorders and clock misalignment; and experimental models to study sleep and clocks in aging and longevity. This book is useful for advanced undergraduate and graduate students, and researchers, educators, and other biomedical professionals.

Human Circadian Physiology

Human Circadian Physiology PDF Author: Charles A. Czeisler
Publisher:
ISBN:
Category : Human physiology
Languages : en
Pages : 692

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Book Description


Aspects of Pacemakers

Aspects of Pacemakers PDF Author: Oliver Vonend
Publisher: BoD – Books on Demand
ISBN: 953307616X
Category : Medical
Languages : en
Pages : 210

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Book Description
Outstanding steps forward were made in the last decades in terms of identification of endogenous pacemakers and the exploration of their controllability. New "artifical" devices were developed and are now able to do much more than solely pacemaking of the heart. In this book different aspects of pacemaker - functions and interactions, in various organ systems were examined. In addition, various areas of application and the potential side effects and complications of the devices were discussed.

The Circadian Clock

The Circadian Clock PDF Author: Urs Albrecht
Publisher: Springer Science & Business Media
ISBN: 1441912622
Category : Science
Languages : en
Pages : 300

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Book Description
With the invitation to edit this volume, I wanted to take the opportunity to assemble reviews on different aspects of circadian clocks and rhythms. Although most c- tributions in this volume focus on mammalian circadian clocks, the historical int- duction and comparative clocks section illustrate the importance of various other organisms in deciphering the mechanisms and principles of circadian biology. Circadian rhythms have been studied for centuries, but only recently, a mole- lar understanding of this process has emerged. This has taken research on circadian clocks from mystic phenomenology to a mechanistic level; chains of molecular events can describe phenomena with remarkable accuracy. Nevertheless, current models of the functioning of circadian clocks are still rudimentary. This is not due to the faultiness of discovered mechanisms, but due to the lack of undiscovered processes involved in contributing to circadian rhythmicity. We know for example, that the general circadian mechanism is not regulated equally in all tissues of m- mals. Hence, a lot still needs to be discovered to get a full understanding of cir- dian rhythms at the systems level. In this respect, technology has advanced at high speed in the last years and provided us with data illustrating the sheer complexity of regulation of physiological processes in organisms. To handle this information, computer aided integration of the results is of utmost importance in order to d- cover novel concepts that ultimately need to be tested experimentally.