scholarly journals Paradigm shifts in electrophysiological mechanisms of atrial fibrillation

EP Europace ◽  
2020 ◽  
Author(s):  
Ulrich Schotten ◽  
Seungyup Lee ◽  
Stef Zeemering ◽  
Albert L Waldo
Keyword(s):  
Atrial Fibrillation ◽  
Double Layers ◽  
Paradigm Shifts ◽  
New Techniques ◽  
Activation Patterns ◽  
Large Variability ◽  
The Past ◽  
Different Types ◽  
Source Of Information ◽  
Electrophysiological Mechanism

Abstract Determining the sequence of activation is a major source of information for understanding the electrophysiological mechanism(s) of atrial fibrillation (AF). However, the complex morphology of the electrograms hampers their analysis, and has stimulated generations of electrophysiologists to develop a large variety of technologies for recording, pre-processing, and analysis of fibrillation electrograms. This variability of approaches is mirrored by a large variability in the interpretation of fibrillation electrograms and, thereby, opinions regarding the basic electrophysiological mechanism(s) of AF vary widely. Multiple wavelets, different types of re-entry including rotors, double layers, multiple focal activation patterns all have been advocated, and a comprehensive and commonly accepted paradigm for the fundamental mechanisms of AF is still lacking. Here, we summarize the Maastricht perspective and Cleveland perspective regarding AF mechanism(s). We also describe some of the key observations in mapping of AF reported over the past decades, and how they changed over the years, often as results of new techniques introduced in the experimental field of AF research.

scholarly journals From Gene Targeting to Genome Editing: Transgenic animals applications and beyond

2015 ◽  
Vol 87 (2 suppl) ◽  
pp. 1323-1348 ◽  
Author(s):  
MAURÍCIO ROCHA-MARTINS ◽  
GABRIEL R. CAVALHEIRO ◽  
GABRIEL E. MATOS-RODRIGUES ◽  
RODRIGO A.P. MARTINS
Keyword(s):  
Genome Editing ◽  
Biomedical Research ◽  
Transgenic Animals ◽  
Paradigm Shifts ◽  
New Techniques ◽  
Future Directions ◽  
Cellular Physiology ◽  
The Past ◽  
Genome Modification ◽  
Help Model

ABSTRACTGenome modification technologies are powerful tools for molecular biology and related areas. Advances in animal transgenesis and genome editing technologies during the past three decades allowed systematic interrogation of gene function that can help model how the genome influences cellular physiology. Genetic engineering via homologous recombination (HR) has been the standard method to modify genomic sequences. Nevertheless, nuclease-guided genome editing methods that were developed recently, such as ZFN, TALEN and CRISPR/Cas, opened new perspectives for biomedical research. Here, we present a brief historical perspective of genome modification methods, focusing on transgenic mice models. Moreover, we describe how new techniques were discovered and improved, present the paradigm shifts and discuss their limitations and applications for biomedical research as well as possible future directions.

Palaeopathology of osteoarthritis

2016 ◽  
Author(s):  
Juliet Rogers ◽  
Paul Dieppe
Keyword(s):  
Bone Formation ◽  
Skeletal Remains ◽  
Human Populations ◽  
New Bone Formation ◽  
Osteophyte Formation ◽  
The Past ◽  
High Prevalence ◽  
Different Types ◽  
Source Of Information ◽  
Over Time

Palaeopathology is the study of disease in the past. Various different types of data can be used, including literature, paintings, and sculpture. In addition, for the rheumatic diseases, skeletal remains offer a particularly rich source of information for the palaeopathologist. This chapter only discusses the skeletal palaeopathology of osteoarthritis (OA). OA leaves characteristic imprints on the skeleton, such as osteophytes and bony sclerosis, which survive death, burial, and the recovery of skeletons. This has allowed researchers to compare the prevalence and distribution of OA within and between joints in skeletal collections obtained from different ancient populations in various countries. The data have shown that while OA has been common in all human populations studied, the nature, prevalence, and intra-articular distribution of the disease in different joints have probably changed over time. A high prevalence of elbow OA has been observed in many collections of human skeletons, suggesting that this joint may be more prone to the disease than generally thought, but that it might remain asymptomatic in the majority of people affected. In addition, skeletal palaeopathologists have found an association between osteophyte formation and enthesophytes, suggesting that some people may have a predisposition to osteoarticular changes characterized by new bone formation. OA has also been described and studied in different primate and other animal skeletons, providing further fascinating insights into the condition.

Stellar Evolution

1962 ◽  
Vol 11 (02) ◽  
pp. 137-143
Author(s):  
M. Schwarzschild
Keyword(s):  
Solar System ◽  
Stellar Evolution ◽  
Space Craft ◽  
New Techniques ◽  
Substantial Body ◽  
Individual Stars ◽  
The Past ◽  
Evolution Of Galaxies ◽  
History Of ◽  
Fast Flow

It is perhaps one of the most important characteristics of the past decade in astronomy that the evolution of some major classes of astronomical objects has become accessible to detailed research. The theory of the evolution of individual stars has developed into a substantial body of quantitative investigations. The evolution of galaxies, particularly of our own, has clearly become a subject for serious research. Even the history of the solar system, this close-by intriguing puzzle, may soon make the transition from being a subject of speculation to being a subject of detailed study in view of the fast flow of new data obtained with new techniques, including space-craft.

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Prawne regulacje pobierania i transplantacji narządów oraz tkanek w ujęciu europejskiej konwencji bioetycznej

2016 ◽  
pp. 52-65
Author(s):  
Patryk Kołodyński ◽  
Paulina Drab
Keyword(s):  
Ex Vivo ◽  
Legal Aspects ◽  
European Convention ◽  
The Public ◽  
Additional Protocol ◽  
The Past ◽  
Reliable Source ◽  
International Legal Order ◽  
Definition Of ◽  
Source Of Information

Over the past several years, transplantology has become one of the fastest developing areas of medicine. The reason is, first and foremost, a significant improvement of the results of successful transplants. However, much controversy arouse among the public, on both medical and ethical grounds. The article presents the most important concepts and regulations relating to the collection and transplantation of organs and tissues in the context of the European Convention on Bioethics. It analyses the convention and its additional protocol. The article provides the definition of transplantation and distinguishes its types, taking into account the medical criteria for organ transplants. Moreover, authors explained the issue of organ donation ex vivo and ex mortuo. The European Convention on Human Rights and Biomedicine clearly regulates the legal aspects concerning the transplantation and related basic concepts, and therefore provides a reliable source of information about organ transplantation and tissue. This act is a part of the international legal order, which includes the established codification of bioethical standards.

Is Healthcare Special?

2018 ◽  
Author(s):  
Gordon Moore ◽  
John A. Quelch ◽  
Emily Boudreau
Keyword(s):  
Consumer Choice ◽  
Special Relationship ◽  
Individual Choice ◽  
Health Consequences ◽  
Critical Question ◽  
The Past ◽  
Different Types ◽  
Collective Benefit ◽  
Patient Ethics

Chapter 2 asks the critical question of whether healthcare is different from other consumer-driven markets. In the past, many pushed back on the notion that healthcare could be a consumer-driven industry, arguing that it is fundamentally different from other markets. This chapter acknowledges and reviews these critiques, highlighting four areas that might present challenges to increasing consumer choice in healthcare: the special relationship between doctor and patient, ethics and morality, individual choice versus collective benefit, and the health consequences of consumer choice. In doing so, this chapter also presents a schematic for thinking about the different types of healthcare choices, arguing that not all choices are equal and consumers may be more prepared to make decisions in some areas as opposed to others. In presenting the counterargument to consumer choice, this chapter asks the reader to consider the drawbacks and potential limitations of consumer choice in healthcare.

Vietnamese Historical Writing

2018 ◽  
Author(s):  
Patricia Pelley
Keyword(s):  
Cold War ◽  
East Asian ◽  
History Writing ◽  
Southern State ◽  
The Past ◽  
South Vietnam ◽  
Political Function ◽  
Different Types ◽  
The Cold War ◽  
North Vietnam

This chapter demonstrates how the process of decolonization and the ensuing separation of Vietnam into a northern and southern state as part of the Cold War in Asia led to different types of history-writing. In both Vietnamese regimes, the writing of history had to serve the state, and in both countries historians emphasized its political function. Whereas North Vietnam located itself in an East Asian and Marxist context, historians of South Vietnam positioned it within a Southeast Asian setting and took a determinedly anti-communist position. After 1986—over a decade after reunification—with past tensions now relaxed, the past could be revaluated more openly under a reformist Vietnamese government that now also permitted much greater interaction with foreign historians.

Different Types of Auricular Keloids and Treatment by Intralesional Cryosurgery: Best Practice for Obtaining Long-Lasting Clinical Results

Dermatology ◽  
2021 ◽  
pp. 1-10
Author(s):  
Yaron Har-Shai ◽  
Lior Har-Shai ◽  
Viktor A. Zouboulis ◽  
Christos C. Zouboulis
Keyword(s):  
Quality Of Life ◽  
Body Image ◽  
Recurrence Rate ◽  
Best Practice ◽  
Clinical Results ◽  
Psychosocial Impact ◽  
Aesthetic Outcome ◽  
The Past ◽  
Different Types

<b><i>Background:</i></b> Auricular keloids belong to the most perplexing medical conditions, which have significant psychosocial impact on the patient’s body image and quality of life. <b><i>Summary:</i></b> The article is purposed to provide dermatologists and plastic surgeons with the best proven practice using intralesional cryosurgery for the treatment of the different auricular keloid types in order to obtain superior clinical results by minimizing the probability of recurrence. In the past 20 years, the authors have developed novel procedures in order to increase the effectiveness of intralesional cryosurgery on auricular keloids, including hydrodissection, warm gauze technique, and excision of dangling skin. Long-lasting clinical results with a low recurrence rate and a satisfactory aesthetic outcome are achieved with no deformation of the ear framework.

scholarly journals Barriers to identifying and obtaining CME: a national survey of physicians, nurse practitioners and physician assistants

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Maureen O’Brien Pott ◽  
Anissa S. Blanshan ◽  
Kelly M. Huneke ◽  
Barbara L. Baasch Thomas ◽  
David A. Cook
Keyword(s):  
Travel Time ◽  
Nurse Practitioners ◽  
Professional Associations ◽  
Physician Assistants ◽  
Age Group ◽  
Sources Of Information ◽  
Online Search ◽  
The Past ◽  
Online Tools ◽  
Source Of Information

Abstract Background CPD educators and CME providers would benefit from further insight regarding barriers and supports in obtaining CME, including sources of information about CME. To address this gap, we sought to explore challenges that clinicians encounter as they seek CME, and time and monetary support allotted for CME. Methods In August 2018, we surveyed licensed US clinicians (physicians, nurse practitioners, and physician assistants), sampling 100 respondents each of family medicine physicians, internal medicine and hospitalist physicians, medicine specialist physicians, nurse practitioners, and physician assistants (1895 invited, 500 [26.3%] responded). The Internet-based questionnaire addressed barriers to obtaining CME, sources of CME information, and time and monetary support for CME. Results The most often-selected barriers were expense (338/500 [68%]) and travel time (N = 286 [57%]). The source of information about CME activities most commonly selected was online search (N = 348 [70%]). Direct email, professional associations, direct mail, and journals were also each selected by > 50% of respondents. Most respondents reported receiving 1–6 days (N = 301 [60%]) and $1000–$5000 (n = 263 [53%]) per year to use in CME activities. Most (> 70%) also reported no change in time or monetary support over the past 24 months. We found few significant differences in responses across clinician type or age group. In open-ended responses, respondents suggested eight ways to enhance CME: optimize location, reduce cost, publicize effectively, offer more courses and content, allow flexibility, ensure accessibility, make content clinically relevant, and encourage application. Conclusions Clinicians report that expense and travel time are the biggest barriers to CME. Time and money support is limited, and not increasing. Online search and email are the most frequently-used sources of information about CME. Those who organize and market CME should explore options that reduce barriers of time and money, and creatively use online tools to publicize new offerings.

scholarly journals Flexibility of joint production in mixed fisheries and implications for management

2021 ◽  
Author(s):  
Florence Briton ◽  
Olivier Thébaud ◽  
Claire Macher ◽  
Caleb Gardner ◽  
Lorne Richard Little
Keyword(s):  
Economic Performance ◽  
Economic Incentives ◽  
Joint Production ◽  
Total Allowable Catch ◽  
Individual Transferable Quotas ◽  
The Past ◽  
Different Types ◽  
Commercial Species ◽  
Management Recommendations ◽  
Production Problems

Abstract Over the past decade, efforts have been made to factor technical interactions into management recommendations for mixed fisheries. Yet, the dynamics underlying joint production in mixed fisheries are generally poorly captured in operational mixed fisheries models supporting total allowable catch advice. Using an integrated ecological–economic simulation model, we explore the extent to which fishers are likely to alter the species composition of their landings in a mixed fishery managed with individual transferable quotas, the Australian Southern and Eastern Scalefish and Shark Fishery. Our simulations capture three different types of joint production problems, highlighting the flexibility that exists in terms of achievable catch compositions when quota markets provide the economic incentives to adapt fishing practices to quota availability. These results highlight the importance of capturing the drivers of fishing choices when advising TAC decisions in mixed fisheries. We also identify a hierarchy of species in this fishery, with harvest targets set for primary commercial species determining most of its socio-economic performance.

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