scholarly journals On the behavior of 1-Laplacian ratio cuts on nearly rectangular domains

2020 ◽  
Author(s):  
Wesley Hamilton ◽  
Jeremy L Marzuola ◽  
Hau-tieng Wu
Keyword(s):  
Dimensional Euclidean Space ◽  
Practical Application ◽  
Circular Arc ◽  
The Past ◽  
Open Questions ◽  
Connected Set ◽  
Original Domain ◽  
First Eigenfunction ◽  
Spectral Cut ◽  
Distance To The Boundary

Abstract The $p$-Laplacian has attracted more and more attention in data analysis disciplines in the past decade. However, there is still a knowledge gap about its behavior, which limits its practical application. In this paper, we are interested in its iterative behavior in domains contained in two-dimensional Euclidean space. Given a connected set $\varOmega _0 \subset \mathbb{R}^2$, define a sequence of sets $(\varOmega _n)_{n=0}^{\infty }$ where $\varOmega _{n+1}$ is the subset of $\varOmega _n$ where the first eigenfunction of the (properly normalized) Neumann $p$-Laplacian $ -\varDelta ^{(p)} \phi = \lambda _1 |\phi |^{p-2} \phi $ is positive (or negative). For $p=1$, this is also referred to as the ratio cut of the domain. We conjecture that these sets converge to the set of rectangles with eccentricity bounded by 2 in the Gromov–Hausdorff distance as long as they have a certain distance to the boundary $\partial \varOmega _0$. We establish some aspects of this conjecture for $p=1$ where we prove that (1) the 1-Laplacian spectral cut of domains sufficiently close to rectangles is a circular arc that is closer to flat than the original domain (leading eventually to quadrilaterals) and (2) quadrilaterals close to a rectangle of aspect ratio $2$ stay close to quadrilaterals and move closer to rectangles in a suitable metric. We also discuss some numerical aspects and pose many open questions.

scholarly journals Recent progress understanding pathophysiology and genesis of brain AVM—a narrative review

2021 ◽  
Author(s):  
Hans-Jakob Steiger
Keyword(s):  
Large Degree ◽  
Advanced Imaging ◽  
Genetic Origin ◽  
The Past ◽  
Open Questions ◽  
Brain Avm ◽  
Pubmed Search ◽  
Substantial Progress ◽  
The Individual ◽  
Arterial Aneurysms

AbstractConsiderable progress has been made over the past years to better understand the genetic nature and pathophysiology of brain AVM. For the actual review, a PubMed search was carried out regarding the embryology, inflammation, advanced imaging, and fluid dynamical modeling of brain AVM. Whole-genome sequencing clarified the genetic origin of sporadic and familial AVM to a large degree, although some open questions remain. Advanced MRI and DSA techniques allow for better segmentation of feeding arteries, nidus, and draining veins, as well as the deduction of hemodynamic parameters such as flow and pressure in the individual AVM compartments. Nonetheless, complete modeling of the intranidal flow structure by computed fluid dynamics (CFD) is not possible so far. Substantial progress has been made towards understanding the embryology of brain AVM. In contrast to arterial aneurysms, complete modeling of the intranidal flow and a thorough understanding of the mechanical properties of the AVM nidus are still lacking at the present time.

Soft Power Effectiveness: Problem of Evaluation

2015 ◽  
pp. 48-58
Author(s):  
E. Kharitonova
Keyword(s):  
Soft Power ◽  
Point Of View ◽  
State Agencies ◽  
Practical Application ◽  
Theoretical Understanding ◽  
Policy Makers ◽  
The Past ◽  
Focus On Results ◽  
Need To Evaluate ◽  
Power Concept

The article focuses on the task of measuring and evaluating a state's soft power. While the soft power concept developed by Joseph Nye is currently widely accepted and used, its theoretical understanding and practical application remains challenging. Both international relations scholars and those responsible for soft power in governmental and non-state agencies are looking for the tools to assess their work and the country's standing in the world in terms of soft power. As the author of the concept and other researchers noted, evaluation and measurement may be difficult due to the number of influencing factors including the use of hard power that can overshadow soft power efforts, and also because soft power efforts can bring results only in a distant period of time. However, in response to the researchers' and policy makers' need to evaluate, measure and compare soft power related parameters, a number of international ratings evolved during the past several years, such as various ratings of soft power, nation brands, countries' reputation and presence. At the same time, such rankings have several weaknesses. First of all, they present mainly the western point of view which focuses on the parameters important for western audiences and may overlook characteristics important for other, non-western cultures. They also may be subjective due to financial reasons. Besides that, while some of the ratings aim to evaluate resources or assets of nations' soft power, other focus on results like influence or reputation. Evaluation of instruments used to enhance a country's soft power and their effectiveness is also important. In many cases, even significant resources of soft power do not guarantee strong positions in this context. Comparing certain countries' positions in different ratings helps to understand a country's standing in terms of soft power, identify strong sides and analyze whether a state's soft power potential transforms into the desired outcomes.

scholarly journals Personalized Medicine in Cancer

2015 ◽  
Vol 32 (3) ◽  
pp. 153-163
Author(s):  
Md Mizanur Rahman
Keyword(s):  
Personalized Medicine ◽  
Single Gene ◽  
Biomedical Science ◽  
Practical Application ◽  
Molecular Alteration ◽  
New Era ◽  
Patients With Cancer ◽  
The Past ◽  
Molecular Aspects

Current and emerging biomedical science efforts are driven by determining how to improve clini-cal outcomes for patients. High-throughput tech-nology has revolutionized the area of transla-tional research, confirming the high complexity and heterogeneity of common diseases, partic-ularly cancer. Therefore, moving from ‘classic’ single-gene-based molecular investigation to molecular network research might result in dis-covering clinical implications faster and more efficiently .Molecular characterization of tumour cells enables refinement of classifications for many cancers and can sometimes guide treatment. Malignant diseases are no longer classified only by tumour site and histology but are separated into various homogenous molecular subtypes, distinguished by a presumed key molecular alteration. Therapies for patients with cancer have changed gradually over the past decade, moving away from the administration of broadly acting cytotoxic drugs towards the use of more-specific therapies that are targeted to each tumour. To facilitate this shift, tests need to be developed to identify those individuals who require therapy and those who are most likely to benefit from certain therapies. In particular, tests that predict the clinical outcome for patients on the basis of the genes expressed by their tumours are likely to increasingly affect patient management, heralding a new era of personalized medicine. In this review a brief discussion on definition and molecular aspects of personalized medicine and its practical application for the management of common solid cancers are highlighted.J Bangladesh Coll Phys Surg 2014; 32: 153-163

scholarly journals Social care for the migrant population in Spain: needs and strengths of organisations during the COVID-19 pandemic and infodemic

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Tamara Bueno Doral ◽  
María Lara ◽  
Noelia García‐Castillo
Keyword(s):  
Third Sector ◽  
Migrant Population ◽  
Health Crisis ◽  
Content Type ◽  
Good Practices ◽  
Four Dimensions ◽  
The Past ◽  
Open Questions ◽  
Third Sector Organisations ◽  
Key Issues

Purpose In the past months, the authors have experienced an exceptional global situation that especially affects the most vulnerable population. This paper aims to analyse the needs, strengths and good practices of the organisations that have continued to study with the migrant population during the health crisis. The main objective was to determine how the health, social and communication crisis has affected the management of the organisation itself, the communications with its direct beneficiaries, the communications with the rest of society, as well as the perception that organisations specialised in migration have about how media has communicated the information of COVID-19 and migrant population. Design/methodology/approach The authors have circulated a questionnaire with open questions that covered the four dimensions previously mentioned. Findings The results show the analysis of the answers of 11 of the most important national and international organisations in the field of migration and refuge that operate in Spain. Originality/value Key issues have emerged related not only to the principal management concerns, internal digital communication, the adaptability of external communication and the major effort required to provide information about migration but also to innovative good practices. That other third sector organisations focussed on migration will be able to apply in the future and in other geographic areas.

scholarly journals The fundamental concepts of cultural anthropology applied in the theory and practice of the anthropological theater

2021 ◽  
pp. 1-10
Author(s):  
Polina Mikhailovna Stepanova
Keyword(s):  
Cultural Anthropology ◽  
Modern Art ◽  
Theory And Practice ◽  
Practical Application ◽  
Social Anthropology ◽  
The Past ◽  
Practical Tool ◽  
Key Terms ◽  
Jerzy Grotowski ◽  
Experimental Stage

This article explores the classical terms and concepts of cultural anthropology, which have found practical application in the performances, paratheatrical experiments and actions of the Polish experimental stage director Jerzy Grotowski (1933–1999) and collectives of the modern anthropological theater that continue the pursuits of Grotowski of the late XX century. The methods and terms of cultural (social) anthropology by A. van Gennep, V. Turner, M. Eliade, B. Malinowski and structural anthropology by C. Levi-Strauss give a better perspective on the specific terminological apparatus of Grotowski, unique practical discoveries of his works, and conceptual basis of theatrical anthropology as one of the paramount phenomena in the development of modern art. This article is first to discuss the problems of the emergence and formation of anthropological methodology as the framework for creating a scientific apparatus for understanding ritual-theatrical forms, as well as practical tool for artistic expression in the theatrical and paratheatrical experiments. Based on the fundamental works of the school of cultural anthropology, the author reveals the key terms of modern anthropological theater. As a result of studying the methods and approaches of cultural anthropology, the author determines the new unique technique of the modern Polish theater ensembles based not on the reconstruction of theatrical forms of the past, but rather reactualization of the mythological structures in the process of creating ritual-theatrical action.

scholarly journals Immunotherapy in hematological malignancies: recent advances and open questions

Immunotherapy ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1215-1229
Author(s):  
Essam A Tawfik ◽  
Norah A Aldrak ◽  
Shahad H Albrahim ◽  
Dunia A Alzahrani ◽  
Haya A Alfassam ◽  
...  
Keyword(s):  
Hematological Malignancies ◽  
Hematopoietic Malignancy ◽  
Hematopoietic Malignancies ◽  
The Past ◽  
Open Questions ◽  
Cell Immunotherapy ◽  
Different Types ◽  
Us Fda ◽  
Approved Drugs ◽  
Fda Approved Drugs

Over recent years, tremendous advances in immunotherapy approaches have been observed, generating significant clinical progress. Cancer immunotherapy has been shown, in different types of blood cancers, to improve the overall survival of patients. Immunotherapy treatment of hematopoietic malignancies is a newly growing field that has been accelerating over the past years. Several US FDA approved drugs and cell-based therapies are being exploited in the late stage of clinical trials. This review attempt to highlight and discuss the numerous innovative immunotherapy approaches of hematopoietic malignancy ranging from nonmyeloablative transplantation, T-cell immunotherapy, natural killer cells and immune agonist to monoclonal antibodies and vaccination. In addition, a brief discussion on the future advances and accomplishments required to counterpart the current immunotherapeutic approaches for hematopoietic malignancies were also highlighted.

Regulation of risk

1981 ◽  
Vol 376 (1764) ◽  
pp. 199-204 ◽  
Keyword(s):  
Quantitative Methods ◽  
Health And Safety ◽  
Practical Application ◽  
Work Activities ◽  
Quantitative Expression ◽  
The Past ◽  
Risks And Benefits ◽  
Safety Regulations ◽  
Quantitative Basis ◽  
Growth Industry

Health and safety regulations have always been concerned with risk, though not always overtly. The quantitative expression of risk does not appear in regulations and rarely in guidance materials but is inherent in the policy underlying the development of regulations and in their practical application. The ways in which actual and perceived expressions of risk are used in regulatory actions differ widely. Some dangers are treated as unaccept­able and the regulatory policy is to exclude them totally. In the real world, such policies are never completely successful. The head-on collision of trains in main-line working is one example. The deliberate use of known carcinogens as pesticides is another. Other dangers are recognized as inevitable but as being reducible in degree. The regulatory activity is then aimed at limiting the extent to which a citizen can expose other citizens to this danger and, more recently, the extent to which he is permitted to put himself at risk. The balance of risks and benefits and of one risk with another underlie decisions in these cases. Not only consequences but probabilities become relevant. In the past, all, and even now most, of the regulation of risk has been on a non-quantitative basis. Increasingly, there is a desire to make the process more quantitative and to introduce the idea of acceptability. This change is provided for by many of the features of the Health and Safety at Work Act of 1974. Within the framework of that Act, the Health and Safety Commission and its operating arm, the Health and Safety Executive, are developing the more systematic use of quantitative methods of controlling hazards from work activities. The regulation of risk is a growth industry and it behoves us all to clarify our objectives. An aim of zero risk would not be to the benefit of society, but its replacement by more suitable aims is a long and com­plicated process.

Artificial Intelligence (AI): Revolutionizing Digital Marketing

2021 ◽  
pp. 183933492110376
Author(s):  
Patrick van Esch ◽  
J. Stewart Black
Keyword(s):  
Artificial Intelligence ◽  
Social Media ◽  
Real World ◽  
Research Process ◽  
Digital Marketing ◽  
Customer Acquisition ◽  
Special Edition ◽  
Practical Application ◽  
The Past ◽  
Acquisition Costs

Artificial intelligence (AI)-enabled digital marketing is revolutionizing the way organizations create content for campaigns, generate leads, reduce customer acquisition costs, manage customer experiences, market themselves to prospective employees, and convert their reachable consumer base via social media. Real-world examples of organizations who are using AI in digital marketing abound. For example, Red Balloon and Harley Davidson used AI to automate their digital advertising campaigns. However, we are early in the process of both the practical application of AI by firms broadly and by their marketing functions in particular. One could argue that we are even earlier in the research process of conceptualizing, theorizing, and researching the use and impact of AI. Importantly, as with most technologies of significant potential, the application of AI in marketing engenders not just practical considerations but ethical questions as well. The ability of AI to automate activities, that in the past people did, also raises the issue of whether marketing professionals will embrace AI as a means to free them from more mundane tasks to spend time on higher value activities, or will they view AI as a threat to their employment? Given the nascent nature of research on AI at this point, the full capabilities and limitations of AI in marketing are unknown. This special edition takes an important step in illuminating both what we know and what we yet need to research.

scholarly journals Fracton phases of matter

2020 ◽  
Vol 35 (06) ◽  
pp. 2030003 ◽  
Author(s):  
Michael Pretko ◽  
Xie Chen ◽  
Yizhi You
Keyword(s):  
Elasticity Theory ◽  
Bound States ◽  
Spin Liquids ◽  
Exotic Particles ◽  
The Past ◽  
Condensed Matter Theory ◽  
Open Questions ◽  
Introductory Material ◽  
Matter Theory ◽  
New Type

Fractons are a new type of quasiparticle which are immobile in isolation, but can often move by forming bound states. Fractons are found in a variety of physical settings, such as spin liquids and elasticity theory, and exhibit unusual phenomenology, such as gravitational physics and localization. The past several years have seen a surge of interest in these exotic particles, which have come to the forefront of modern condensed matter theory. In this review, we provide a broad treatment of fractons, ranging from pedagogical introductory material to discussions of recent advances in the field. We begin by demonstrating how the fracton phenomenon naturally arises as a consequence of higher moment conservation laws, often accompanied by the emergence of tensor gauge theories. We then provide a survey of fracton phases in spin models, along with the various tools used to characterize them, such as the foliation framework. We discuss in detail the manifestation of fracton physics in elasticity theory, as well as the connections of fractons with localization and gravitation. Finally, we provide an overview of some recently proposed platforms for fracton physics, such as Majorana islands and hole-doped antiferromagnets. We conclude with some open questions and an outlook on the field.

scholarly journals Active Motion Control of a Knee Exoskeleton Driven by Antagonistic Pneumatic Muscle Actuators

Actuators ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 134
Author(s):  
Wei Zhao ◽  
Aiguo Song
Keyword(s):  
Sliding Mode ◽  
Weight Ratio ◽  
Practical Application ◽  
Active Motion ◽  
Pneumatic Muscle ◽  
The Past ◽  
Robotic Devices ◽  
Muscle Actuators ◽  
Further Development ◽  
Rehabilitation Robotic

The pneumatic muscle actuator (PMA) has been widely applied in the researches of rehabilitation robotic devices for its high power to weight ratio and intrinsic compliance in the past decade. However, the high nonlinearity and hysteresis behavior of PMA limit its practical application. Hence, the control strategy plays an important role in improving the performance of PMA for the effectiveness of rehabilitation devices. In this paper, a PMA-based knee exoskeleton based on ergonomics is proposed. Based on the designed knee exoskeleton, a novel proxy-based sliding mode control (PSMC) is introduced to obtain the accurate trajectory tracking. Compared with conventional control approaches, this new PSMC can obtain better performance for the designed PMA-based exoskeleton. Experimental results indicate good tracking performance of this controller, which provides a good foundation for the further development of assist-as-needed training strategies in gait rehabilitation.

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