Maintaining Your Passion for the Job

ERIC Educational Resources Information Center

McClellan, George S.

2012-01-01

There are times when passion for a job is seriously tested by the circumstances and conditions of the work. The accumulated effect of long hours, increasing demand for services, shrinking budgets, intractable issues, litigious environments, and what seems at times like incessant bashing of higher education for political purposes can lead to…

Looking Outside Education: Expanding Our Thinking about Moving Research into Practice

ERIC Educational Resources Information Center

Schneider, Jack

2015-01-01

This essay explores the usefulness of looking outside of education for inspiration, particularly with regard to seemingly intractable issues that have been resigned to the margins. First, it proposes that, rather than comparing education to medicine and law--the traditional comparison fields for education--we turn instead to the "helping…

Learning about War and Peace in the Great Lakes Region of Africa

ERIC Educational Resources Information Center

Bird, Lyndsay

2007-01-01

Two-thirds of the world's conflicts are in Africa. In particular, the Great Lakes region (Rwanda, Burundi, Democratic Republic of Congo, Uganda and Tanzania) continues to see conflicts that are complex, extreme and seemingly intractable. By exploring the narrative experiences of those most affected by the conflicts in the region--specifically…

Addressing Social Determinants Of Health Through Medical-Legal Partnerships.

PubMed

Regenstein, Marsha; Trott, Jennifer; Williamson, Alanna; Theiss, Joanna

2018-03-01

The US health care system needs effective tools to address complex social and environmental issues that perpetuate health inequities, such as food insecurity, education and employment barriers, and substandard housing conditions. The medical-legal partnership is a collaborative intervention that embeds civil legal aid professionals in health care settings to address seemingly intractable social problems that contribute to poor health outcomes and health disparities. More than three hundred health care organizations are home to medical-legal partnerships. This article draws upon national survey data and field research to identify three models of the medical-legal partnership that health care organizations have adopted and the core elements of infrastructure that they share. Financing and commitment from health care organizations are key considerations for sustaining and scaling up the medical-legal partnership as a health equity intervention.

Preventing Bullying through Positive Behavioral Interventions and Supports (PBIS): A Multitiered Approach to Prevention and Integration

ERIC Educational Resources Information Center

Bradshaw, Catherine P.

2013-01-01

Although bullying continues to be a growing public health concern in schools across the United States, there are considerable gaps in the American understanding of effective prevention approaches for addressing this seemingly intractable issue. This article applies a public health approach to addressing bullying through the multitiered Positive…

Vulnerable Decision Points for Disproportionate Office Discipline Referrals: Comparisons of Discipline for African American and White Elementary School Students

ERIC Educational Resources Information Center

Smolkowski, Keith; Girvan, Erik J.; McIntosh, Kent; Nese, Rhonda N. T.; Horner, Robert H.

2016-01-01

Racial disparities in rates of exclusionary school discipline are well documented and seemingly intractable. However, emerging theories on implicit bias show promise in identifying effective interventions. In this study, we used school discipline data from 1,666 elementary schools and 483,686 office discipline referrals to identify specific…

The Social Funding of Race: The Role of Schooling

ERIC Educational Resources Information Center

Ladson-Billings, Gloria

2018-01-01

Our nation is suffused in questions of race and racism. Despite much scholarly and public discussion we struggle to undo long-held assumptions about race and how it functions. This article looks at race from the perspective of a public commodity that the society "funds" in order to make it seem real and intractable. Throughout the…

Classical Biological Control of Invasive Legacy Crop Pests: New Technologies Offer Opportunities to Revisit Old Pest Problems in Perennial Tree Crops

PubMed Central

Hoddle, Mark S.; Warner, Keith; Steggall, John; Jetter, Karen M.

2014-01-01

Advances in scientific disciplines that support classical biological control have provided “new tools” that could have important applications for biocontrol programs for some long-established invasive arthropod pests. We suggest that these previously unavailable tools should be used in biological control programs targeting “legacy pests”, even if they have been targets of previously unsuccessful biocontrol projects. Examples of “new tools” include molecular analyses to verify species identities and likely geographic area of origin, climate matching and ecological niche modeling, preservation of natural enemy genetic diversity in quarantine, the use of theory from invasion biology to maximize establishment likelihoods for natural enemies, and improved understanding of the interactions between natural enemy and target pest microbiomes. This review suggests that opportunities exist for revisiting old pest problems and funding research programs using “new tools” for developing biological control programs for “legacy pests” could provide permanent suppression of some seemingly intractable pest problems. As a case study, we use citricola scale, Coccus pseudomagnoliarum, an invasive legacy pest of California citrus, to demonstrate the potential of new tools to support a new classical biological control program targeting this insect. PMID:26463063

Precious African American memories, post-racial dreams & the American nation.

PubMed

Martin, Waldo E

2011-01-01

This interdisciplinary essay explores a fundamental paradox at the heart of American race relations since the 1960s: "the changing same." The more things change; the more they remain the same. Combining historical and social-scientific evidence with autobiographical reflections, this discussion critically probes the paradoxical decline and persistence of two dimensions of our enduring racial quagmire: racial inequality and white supremacy. The essay argues that these powerful and interrelated elements of America's continuing racial dilemma demand a massive democratic movement to alleviate both at once. This wide-ranging struggle to realize the promise of American democracy requires more than just a revitalized African American Freedom Struggle that is both intraracial and interracial. Progress toward resolving the seemingly intractable problem of racial inequality in the United States demands far more than intensified efforts to alleviate economic inequality; it requires alleviating white supremacy as well.

A new rejection of moral expertise.

PubMed

Cowley, Christopher

2005-01-01

There seem to be two clearly-defined camps in the debate over the problem of moral expertise. On the one hand are the "Professionals", who reject the possibility entirely, usually because of the intractable diversity of ethical beliefs. On the other hand are the "Ethicists", who criticise the Professionals for merely stipulating science as the most appropriate paradigm for discussions of expertise. While the subject matter and methodology of good ethical thinking is certainly different from that of good clinical thinking, they argue, this is no reason for rejecting the possibility of a distinctive kind of expertise in ethics, usually based on the idea of good justification. I want to argue that both are incorrect, partly because of the reasons given by one group against the other, but more importantly because both neglect what is most distinctive about ethics: that it is personal in a very specific way, without collapsing into relativism.

Modeling virus capsids and their protein binding -- the search for weak regions within the HIV capsid

NASA Astrophysics Data System (ADS)

Sankey, Otto; Benson, Daryn

2010-10-01

Viruses remain a threat to the health of humans worldwide with 33 million infected with AIDS. Viruses are ubiquitous infecting animals, plants, and bacteria. Each virus infects in its own unique manner making the problem seem intractable. However, some general physical steps apply to many viruses and the application of basic physical modeling can potentially have great impact. The aim of this theoretical study is to investigate the stability of the HIV viral capsid (protein shell). The structural shell can be compromised by physical probes such as pulsed laser light. But what are the weakest regions of the capsid so that we can begin to understand vulnerabilities of these deadly materials? The atomic structure of HIV capsids is not precisely known and we begin by describing our work to model the capsid structure. Next we describe a course grained model to investigate protein interactions within the capsid.

Integrative Convergence in Neuroscience: Trajectories, Problems, and the Need for a Progressive Neurobioethics

NASA Astrophysics Data System (ADS)

Giordano, J.

The advanced integrative scientific convergence (AISC) model represents a viable approach to neuroscience. Beyond simple multi-disciplinarity, the AISC model unifies constituent scientific and technological fields to foster innovation, invention and new ways of addressing seemingly intractable questions. In this way, AISC can yield novel methods and foster new trajectories of knowledge and discovery, and yield new epistemologies. As stand-alone disciplines, each and all of the constituent fields generate practical and ethical issues, and their convergence may establish a unique set of both potential benefits and problems. To effectively attend to these contingencies requires pragmatic assessment of the actual capabilities and limits of neurofocal AISC, and an openness to what new knowledge and scientific/technological achievements may be produced, and how such outcomes can affect humanity, the human condition, society and the global environment. It is proposed that a progressive neurobioethics may be needed to establish both a meta-ethical framework upon which to structure ethical decisions, and a system and method of ethics that is inclusive, convergent and innovative, and in thus aligned with and meaningful to use of an AISC model in neuroscience.

Abusing the Unprotected: A Study of the Misuse of Aversive Behavior Modification Techniques and Weaknesses in the Regulatory Structure.

ERIC Educational Resources Information Center

New York State Commission on Quality of Care for the Mentally Disabled, Albany.

This report examines issues concerned with the use of aversive behavior modification techniques in actual treatment practices at one intermediate care facility for the mentally retarded. The review of these practices reveals how, once the philosophy of using aversives takes hold at a program (to deal with seemingly intractable behaviors), its…

Active Subspace Methods for Data-Intensive Inverse Problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Qiqi

2017-04-27

The project has developed theory and computational tools to exploit active subspaces to reduce the dimension in statistical calibration problems. This dimension reduction enables MCMC methods to calibrate otherwise intractable models. The same theoretical and computational tools can also reduce the measurement dimension for calibration problems that use large stores of data.

Using genetic algorithms to determine near-optimal pricing, investment and operating strategies in the electric power industry

NASA Astrophysics Data System (ADS)

Wu, Dongjun

Network industries have technologies characterized by a spatial hierarchy, the "network," with capital-intensive interconnections and time-dependent, capacity-limited flows of products and services through the network to customers. This dissertation studies service pricing, investment and business operating strategies for the electric power network. First-best solutions for a variety of pricing and investment problems have been studied. The evaluation of genetic algorithms (GA, which are methods based on the idea of natural evolution) as a primary means of solving complicated network problems, both w.r.t. pricing: as well as w.r.t. investment and other operating decisions, has been conducted. New constraint-handling techniques in GAs have been studied and tested. The actual application of such constraint-handling techniques in solving practical non-linear optimization problems has been tested on several complex network design problems with encouraging initial results. Genetic algorithms provide solutions that are feasible and close to optimal when the optimal solution is know; in some instances, the near-optimal solutions for small problems by the proposed GA approach can only be tested by pushing the limits of currently available non-linear optimization software. The performance is far better than several commercially available GA programs, which are generally inadequate in solving any of the problems studied in this dissertation, primarily because of their poor handling of constraints. Genetic algorithms, if carefully designed, seem very promising in solving difficult problems which are intractable by traditional analytic methods.

Drug discovery chemistry: a primer for the non-specialist.

PubMed

Jordan, Allan M; Roughley, Stephen D

2009-08-01

Like all scientific disciplines, drug discovery chemistry is rife with terminology and methodology that can seem intractable to those outside the sphere of synthetic chemistry. Derived from a successful in-house workshop, this Foundation Review aims to demystify some of this inherent terminology, providing the non-specialist with a general insight into the nomenclature, terminology and workflow of medicinal chemists within the pharmaceutical industry.

Treatment of anismus in intractable constipation with botulinum A toxin.

PubMed

Hallan, R I; Williams, N S; Melling, J; Waldron, D J; Womack, N R; Morrison, J F

1988-09-24

In seven patients with anismus the striated sphincter muscle complex was selectively weakened by local injection of Clostridium botulinum type A toxin. Symptom scores improved significantly and correlated with a significant reduction in the maximum voluntary and canal squeeze pressure and a significant increase in the anorectal angle on straining. Botulinum A toxin seems to be promising treatment for some patients with anismus.

Women Reaching Women: Change in Action--Using Action Learning to Help Address Seemingly Intractable and Large Scale Social Issues

ERIC Educational Resources Information Center

Langley, Dawn; Watts, Richard

2010-01-01

In 2008, 28 women from the Women's Institute volunteered to join us in a project exploring the issue of world poverty and gender inequality, specifically highlighting the disproportionate effects of climate change on women. Collectively we were asking a big question about how we as individuals, based in England, make a difference on a global…

The Kadison–Singer Problem in mathematics and engineering

PubMed Central

Casazza, Peter G.; Tremain, Janet Crandell

2006-01-01

We will see that the famous intractible 1959 Kadison–Singer Problem in C*-algebras is equivalent to fundamental open problems in a dozen different areas of research in mathematics and engineering. This work gives all these areas common ground on which to interact as well as explaining why each area has volumes of literature on their respective problems without a satisfactory resolution. PMID:16461465

Monte Carlo Simulation for Perusal and Practice.

ERIC Educational Resources Information Center

Brooks, Gordon P.; Barcikowski, Robert S.; Robey, Randall R.

The meaningful investigation of many problems in statistics can be solved through Monte Carlo methods. Monte Carlo studies can help solve problems that are mathematically intractable through the analysis of random samples from populations whose characteristics are known to the researcher. Using Monte Carlo simulation, the values of a statistic are…

A "Hands on" Strategy for Teaching Genetic Algorithms to Undergraduates

ERIC Educational Resources Information Center

Venables, Anne; Tan, Grace

2007-01-01

Genetic algorithms (GAs) are a problem solving strategy that uses stochastic search. Since their introduction (Holland, 1975), GAs have proven to be particularly useful for solving problems that are "intractable" using classical methods. The language of genetic algorithms (GAs) is heavily laced with biological metaphors from evolutionary…

Botulinum toxin type-A injection to treat patients with intractable anismus unresponsive to simple biofeedback training

PubMed Central

Zhang, Yong; Wang, Zhen-Ning; He, Lei; Gao, Ge; Zhai, Qing; Yin, Zhi-Tao; Zeng, Xian-Dong

2014-01-01

AIM: To evaluate the efficacy of botulinum toxin type A injection to the puborectalis and external sphincter muscle in the treatment of patients with anismus unresponsive to simple biofeedback training. METHODS: This retrospective study included 31 patients suffering from anismus who were unresponsive to simple biofeedback training. Diagnosis was made by anorectal manometry, balloon expulsion test, surface electromyography of the pelvic floor muscle, and defecography. Patients were given botulinum toxin type A (BTX-A) injection and pelvic floor biofeedback training. Follow-up was conducted before the paper was written. Improvement was evaluated using the chronic constipation scoring system. RESULTS: BTX-A injection combined with pelvic floor biofeedback training achieved success in 24 patients, with 23 maintaining persistent satisfaction during a mean period of 8.4 mo. CONCLUSION: BTX-A injection combined with pelvic floor biofeedback training seems to be successful for intractable anismus. PMID:25253964

Botulinum toxin type-A injection to treat patients with intractable anismus unresponsive to simple biofeedback training.

PubMed

Zhang, Yong; Wang, Zhen-Ning; He, Lei; Gao, Ge; Zhai, Qing; Yin, Zhi-Tao; Zeng, Xian-Dong

2014-09-21

To evaluate the efficacy of botulinum toxin type A injection to the puborectalis and external sphincter muscle in the treatment of patients with anismus unresponsive to simple biofeedback training. This retrospective study included 31 patients suffering from anismus who were unresponsive to simple biofeedback training. Diagnosis was made by anorectal manometry, balloon expulsion test, surface electromyography of the pelvic floor muscle, and defecography. Patients were given botulinum toxin type A (BTX-A) injection and pelvic floor biofeedback training. Follow-up was conducted before the paper was written. Improvement was evaluated using the chronic constipation scoring system. BTX-A injection combined with pelvic floor biofeedback training achieved success in 24 patients, with 23 maintaining persistent satisfaction during a mean period of 8.4 mo. BTX-A injection combined with pelvic floor biofeedback training seems to be successful for intractable anismus.

Multiplex diagnosis of viral infectious diseases (AIDS, hepatitis C, and hepatitis A) based on point of care lateral flow assay using engineered proteinticles.

PubMed

Lee, Jong-Hwan; Seo, Hyuk Seong; Kwon, Jung-Hyuk; Kim, Hee-Tae; Kwon, Koo Chul; Sim, Sang Jun; Cha, Young Joo; Lee, Jeewon

2015-07-15

Lateral flow assay (LFA) is an attractive method for rapid, simple, and cost-effective point of care diagnosis. For LFA-based multiplex diagnosis of three viral intractable diseases (acquired immune deficiency syndrome and hepatitis C and A), here we developed proteinticle-based 7 different 3D probes that display different viral antigens on their surface, which were synthesized in Escherichia coli by self-assembly of human ferritin heavy chain that was already engineered by genetically linking viral antigens to its C-terminus. Each of the three test lines on LFA strip contains the proteinticle probes to detect disease-specific anti-viral antibodies. Compared to peptide probes, the proteinticle probes were evidently more sensitive, and the proteinticle probe-based LFA successfully diagnosed all the 20 patient sera per each disease without a false negative signal, whereas the diagnostic sensitivities in the peptide probe-based LFAs were 65-90%. Duplex and triplex assays performed with randomly mixed patient sera gave only true positive signals for all the 20 serum mixtures without any false positive signals, indicating 100% sensitivity and 100% specificity. It seems that on the proteinticle surface the antigenic peptides have homogeneous orientation and conformation without inter-peptide clustering and hence lead to the enhanced diagnostic performance with solving the problems of traditional diagnostic probes. Although the multiplex diagnosis of three viral diseases above was demonstrated as proof-of-concept here, the proposed LFA system can be applied to multiplex point of care diagnosis of other intractable diseases. Copyright © 2015 Elsevier B.V. All rights reserved.

Cavopulmonary assist: (Em)powering the univentricular Fontan circulation

PubMed Central

Rodefeld, Mark D; Frankel, Steven H; Giridharan, Guruprasad A

2011-01-01

Since the Fontan/Kreutzer procedure was introduced, evolutionary clinical advances via a staged surgical reconstructive approach have markedly improved outcomes for patients with functional single ventricle. However, significant challenges remain. Early stage mortality risk seems impenetrable. Serious morbidities - construed as immutable consequences of palliation - have hardly been addressed. Late functional status is increasingly linked to pathophysiologic consequences of prior staged procedures. As more single ventricle patients survive into adulthood, Fontan failure is emerging as an intractable problem for which there is no targeted therapy. Incremental solutions to address these ongoing problems have not had a measurable impact. Therefore, a fundamental reconsideration of the overall approach is reasonable and warranted. The ability to provide a modest pressure boost (2-6 mmHg) to existing blood flow at the total cavopulmonary connection can effectively restore more stable biventricular status. This would impact not only treatment of late Fontan failure, but also facilitate early surgical repair. A realistic means to provide such a pressure boost has never been apparent. Recent advances are beginning to unravel the unique challenges which must be addressed to realize this goal, with promise to open single ventricle palliation to new therapeutic vistas. PMID:21444049

Inequality--"Wicked Problems", Labour Market Outcomes and the Search for Silver Bullets

ERIC Educational Resources Information Center

Keep, Ewart; Mayhew, Ken

2014-01-01

In recent years concerns about inequality have been growing in prominence within UK policy debates. The many causes of inequality of earnings and income are complex in their interactions and their tendency to reinforce one another. This makes inequality an intractable or "wicked" policy problem, particularly within a contemporary context…

What does the closure of context-sensitive constraints mean for determinism, autonomy, self-determination, and agency?

PubMed

Juarrero, Alicia

2015-12-01

The role of context-sensitive constraints - first as enablers of complexification and subsequently as regulators that maintain the integrity of self-organized, coherent wholes - has only recently begun to be examined. Conceptualizing such organizational constraints in terms of the operations of far from equilibrium, nonlinear dynamic processes rekindles old metaphysical discussions concerning primary and secondary relations, emergence, causality, and the logic of explanation. In particular, far-from-equilibrium processes allow us to rethink how parts-to-whole and whole-to-parts - so-called "mereological"- relationships are constituted. A renewed understanding of recursive feedback and the role context-dependence plays in generating the boundary conditions and the internal organization of complex adaptive systems in turn allows us to redescribe formal and final cause in such a way as to provide a meaningful sense of heretofore seemingly intractable philosophical problems such as autonomy, self-determination, and agency. Copyright © 2015. Published by Elsevier Ltd.

Amoeba-inspired nanoarchitectonic computing: solving intractable computational problems using nanoscale photoexcitation transfer dynamics.

PubMed

Aono, Masashi; Naruse, Makoto; Kim, Song-Ju; Wakabayashi, Masamitsu; Hori, Hirokazu; Ohtsu, Motoichi; Hara, Masahiko

2013-06-18

Biologically inspired computing devices and architectures are expected to overcome the limitations of conventional technologies in terms of solving computationally demanding problems, adapting to complex environments, reducing energy consumption, and so on. We previously demonstrated that a primitive single-celled amoeba (a plasmodial slime mold), which exhibits complex spatiotemporal oscillatory dynamics and sophisticated computing capabilities, can be used to search for a solution to a very hard combinatorial optimization problem. We successfully extracted the essential spatiotemporal dynamics by which the amoeba solves the problem. This amoeba-inspired computing paradigm can be implemented by various physical systems that exhibit suitable spatiotemporal dynamics resembling the amoeba's problem-solving process. In this Article, we demonstrate that photoexcitation transfer phenomena in certain quantum nanostructures mediated by optical near-field interactions generate the amoebalike spatiotemporal dynamics and can be used to solve the satisfiability problem (SAT), which is the problem of judging whether a given logical proposition (a Boolean formula) is self-consistent. SAT is related to diverse application problems in artificial intelligence, information security, and bioinformatics and is a crucially important nondeterministic polynomial time (NP)-complete problem, which is believed to become intractable for conventional digital computers when the problem size increases. We show that our amoeba-inspired computing paradigm dramatically outperforms a conventional stochastic search method. These results indicate the potential for developing highly versatile nanoarchitectonic computers that realize powerful solution searching with low energy consumption.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, I.C., E-mail: docdunc@iafrica.com; Santos, C. Dos

A patient with intractable posterior epistaxis was treated with embolization of the ipsilateral sphenopalatine and facial arteries and contralateral sphenopalatine artery. She continued to bleed despite a seemingly adequate embolization procedure. A second angiogram revealed a significant collateral blood supply to the posterior nasal cavity from the accessory meningeal artery not identified during the first procedure. This was then embolized with no further epistaxis encountered. This case demonstrates yet another collateral arterial pathway that might account for a failed embolization.

Metal Containing Polymers as Fuel Cell Catalysts.

DTIC Science & Technology

1987-06-30

since trivalent cobalt 4ould be inert to substitution. The polymers with heavy metal loadings were intractable and did not seem to be suitable for...of 35 , nydrogen peroxide. This was heated strongly on a not plate until fuming hegan. ’lore hydrogen peroxide was added and he3rting resumed until... chromium (I1) complexes. Summer 1986 - NASA Summer Faculty Fellow (Power Systems Division); investigated advanced energy storage systems to be used on

A variational eigenvalue solver on a photonic quantum processor

PubMed Central

Peruzzo, Alberto; McClean, Jarrod; Shadbolt, Peter; Yung, Man-Hong; Zhou, Xiao-Qi; Love, Peter J.; Aspuru-Guzik, Alán; O’Brien, Jeremy L.

2014-01-01

Quantum computers promise to efficiently solve important problems that are intractable on a conventional computer. For quantum systems, where the physical dimension grows exponentially, finding the eigenvalues of certain operators is one such intractable problem and remains a fundamental challenge. The quantum phase estimation algorithm efficiently finds the eigenvalue of a given eigenvector but requires fully coherent evolution. Here we present an alternative approach that greatly reduces the requirements for coherent evolution and combine this method with a new approach to state preparation based on ansätze and classical optimization. We implement the algorithm by combining a highly reconfigurable photonic quantum processor with a conventional computer. We experimentally demonstrate the feasibility of this approach with an example from quantum chemistry—calculating the ground-state molecular energy for He–H+. The proposed approach drastically reduces the coherence time requirements, enhancing the potential of quantum resources available today and in the near future. PMID:25055053

Investigation of automated task learning, decomposition and scheduling

NASA Technical Reports Server (NTRS)

Livingston, David L.; Serpen, Gursel; Masti, Chandrashekar L.

1990-01-01

The details and results of research conducted in the application of neural networks to task planning and decomposition are presented. Task planning and decomposition are operations that humans perform in a reasonably efficient manner. Without the use of good heuristics and usually much human interaction, automatic planners and decomposers generally do not perform well due to the intractable nature of the problems under consideration. The human-like performance of neural networks has shown promise for generating acceptable solutions to intractable problems such as planning and decomposition. This was the primary reasoning behind attempting the study. The basis for the work is the use of state machines to model tasks. State machine models provide a useful means for examining the structure of tasks since many formal techniques have been developed for their analysis and synthesis. It is the approach to integrate the strong algebraic foundations of state machines with the heretofore trial-and-error approach to neural network synthesis.

Motive attribution asymmetry for love vs. hate drives intractable conflict.

PubMed

Waytz, Adam; Young, Liane L; Ginges, Jeremy

2014-11-04

Five studies across cultures involving 661 American Democrats and Republicans, 995 Israelis, and 1,266 Palestinians provide previously unidentified evidence of a fundamental bias, what we term the "motive attribution asymmetry," driving seemingly intractable human conflict. These studies show that in political and ethnoreligious intergroup conflict, adversaries tend to attribute their own group's aggression to ingroup love more than outgroup hate and to attribute their outgroup's aggression to outgroup hate more than ingroup love. Study 1 demonstrates that American Democrats and Republicans attribute their own party's involvement in conflict to ingroup love more than outgroup hate but attribute the opposing party's involvement to outgroup hate more than ingroup love. Studies 2 and 3 demonstrate this biased attributional pattern for Israelis and Palestinians evaluating their own group and the opposing group's involvement in the current regional conflict. Study 4 demonstrates in an Israeli population that this bias increases beliefs and intentions associated with conflict intractability toward Palestinians. Finally, study 5 demonstrates, in the context of American political conflict, that offering Democrats and Republicans financial incentives for accuracy in evaluating the opposing party can mitigate this bias and its consequences. Although people find it difficult to explain their adversaries' actions in terms of love and affiliation, we suggest that recognizing this attributional bias and how to reduce it can contribute to reducing human conflict on a global scale.

Motive attribution asymmetry for love vs. hate drives intractable conflict

PubMed Central

Waytz, Adam; Young, Liane L.; Ginges, Jeremy

2014-01-01

Five studies across cultures involving 661 American Democrats and Republicans, 995 Israelis, and 1,266 Palestinians provide previously unidentified evidence of a fundamental bias, what we term the “motive attribution asymmetry,” driving seemingly intractable human conflict. These studies show that in political and ethnoreligious intergroup conflict, adversaries tend to attribute their own group’s aggression to ingroup love more than outgroup hate and to attribute their outgroup’s aggression to outgroup hate more than ingroup love. Study 1 demonstrates that American Democrats and Republicans attribute their own party’s involvement in conflict to ingroup love more than outgroup hate but attribute the opposing party’s involvement to outgroup hate more than ingroup love. Studies 2 and 3 demonstrate this biased attributional pattern for Israelis and Palestinians evaluating their own group and the opposing group’s involvement in the current regional conflict. Study 4 demonstrates in an Israeli population that this bias increases beliefs and intentions associated with conflict intractability toward Palestinians. Finally, study 5 demonstrates, in the context of American political conflict, that offering Democrats and Republicans financial incentives for accuracy in evaluating the opposing party can mitigate this bias and its consequences. Although people find it difficult to explain their adversaries’ actions in terms of love and affiliation, we suggest that recognizing this attributional bias and how to reduce it can contribute to reducing human conflict on a global scale. PMID:25331879

On the Need for Artificial Intelligence and Advanced Test and Evaluation Methods for Space Exploration

NASA Astrophysics Data System (ADS)

Scheidt, D. H.; Hibbitts, C. A.; Chen, M. H.; Paxton, L. J.; Bekker, D. L.

2017-02-01

Implementing mature artificial intelligence would create the ability to significantly increase the science return from a mission, while potentially saving costs in mission and instrument operations, and solving currently intractable problems.

Does thalidomide have an analgesic effect? Current status and future directions.

PubMed

Goli, Veeraindar

2007-04-01

Dramatic relief of pain and life-altering changes in quality of life in some patients treated with immunomodulators such as thalidomide compel us to look more closely at unconventional mechanisms that may be involved in propagation of persistent pain. Tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and IL-10 are the cytokines with the most evidence in pain modulation. TNF-alpha and IL-1beta seem to initiate neuropathic pain, IL-6 maintains such pain, and IL-10 inhibits this persistent pain. Thalidomide was found to be effective in animal models by inhibiting TNF-alpha production. Several case reports and case series in humans have demonstrated mixed results, with some patients having dramatic responses, especially in chronic intractable conditions such as complex regional pain syndrome. Thalidomide may be an alternative for some patients with intractable pain. However, use of thalidomide is limited by its neurotoxic and teratogenic effects. Newer analogues may significantly improve the risk/benefit of using such immunomodulators.

Reluctant Rural Regionalists

ERIC Educational Resources Information Center

Hall, Peter V.; Stern, Pamela

2009-01-01

Recently, scholars have begun to explore questions of regionalism and regionalization in rural contexts. Regionalism is often understood and presented as a pragmatic solution to intractable problems of fragmentation, inefficiency, accountability, spillover and neglect in the face of economic restructuring and other external threats. These…

An Affordance-Based Framework for Human Computation and Human-Computer Collaboration.

PubMed

Crouser, R J; Chang, R

2012-12-01

Visual Analytics is "the science of analytical reasoning facilitated by visual interactive interfaces". The goal of this field is to develop tools and methodologies for approaching problems whose size and complexity render them intractable without the close coupling of both human and machine analysis. Researchers have explored this coupling in many venues: VAST, Vis, InfoVis, CHI, KDD, IUI, and more. While there have been myriad promising examples of human-computer collaboration, there exists no common language for comparing systems or describing the benefits afforded by designing for such collaboration. We argue that this area would benefit significantly from consensus about the design attributes that define and distinguish existing techniques. In this work, we have reviewed 1,271 papers from many of the top-ranking conferences in visual analytics, human-computer interaction, and visualization. From these, we have identified 49 papers that are representative of the study of human-computer collaborative problem-solving, and provide a thorough overview of the current state-of-the-art. Our analysis has uncovered key patterns of design hinging on human and machine-intelligence affordances, and also indicates unexplored avenues in the study of this area. The results of this analysis provide a common framework for understanding these seemingly disparate branches of inquiry, which we hope will motivate future work in the field.

A perspective on the future public health: an integrative and ecological framework.

PubMed

Hanlon, Phil; Carlisle, Sandra; Hannah, Margaret; Lyon, Andrew; Reilly, David

2012-11-01

Modernity has brought health and social benefits to many societies, not least through the insights of science and technology. Yet, modernity has also been associated with a number of cultural characteristics, such as materialism, individualism, consumerism and an addiction to continuing economic growth, that seem potentially harmful to health and well-being and inimical to social equity. There is an emerging body of evidence that suggests that, in the affluent world, some of our most intractable contemporary health problems are, in fact, the product of modernity. This suggests that the tools of modernity (its science and its technology) are ill suited to finding solutions. This poses a problem for public health, as this discipline is itself a product of modernity and thus appears ill equipped to deal with the conditions and challenges of a rapidly changing and unstable world, one where the very sustainability of human society is now in question. This paper argues that a new paradigm for the future public health is needed. It presents an integrative, ecological framework as a starting point from which public health might grasp the opportunities for change inherent in the 'modern' threats we face. It suggests a number of features that will need to underpin such a paradigm shift in thinking and practice. However, as this paper is written from the perspective of an affluent, developed society (albeit from a perspective that is explicitly critical of the goals, trends and values that seem to characterise such societies), other voices from other places need to be heard. We hope that others will want to engage with our arguments and suggestions, whether to challenge and refute these, or to further their development.

All in a Knot of One Another's Labours: Self-Determination, Network Organising and Learning

ERIC Educational Resources Information Center

Pedler, Mike

2012-01-01

This essay is about how to learn to organise to tackle the intractable and most difficult problems of organisations and societies. It opens with a discussion of the nature of such problems, which are the spur for Revans' action learning and the focus of some recent thinking on leadership. Action learning works on the basis of peer relationships…

GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

EPA Science Inventory

The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

90 Years of Rural Development Programs.

ERIC Educational Resources Information Center

Rasmussen, Wayne D.

1985-01-01

Discusses history of United States government programs to ameliorate rural living and economic conditions. Contrasts early successful efforts to improve physical characteristics--road, electricity--with recent lack of success in dealing with intractable problems--unemployment, persistent poverty. Chart of rural development actions outlines rural…

Wicked problems and a 'wicked' solution.

PubMed

Walls, Helen L

2018-04-13

'Wicked' is the term used to describe some of the most challenging and complex issues of our time, many of which threaten human health. Climate change, biodiversity loss, persisting poverty, the advancing obesity epidemic, and food insecurity are all examples of such wicked problems. However there is a strong body of evidence describing the solutions for addressing many of these problems. Given that much is known about how many of these problems could be addressed - and given the risks of not acting - what will it take to create the 'tipping point' needed for effective action? A recent (2015) court ruling in The Hague held that the Dutch government's stance on climate change was illegal, ordering them to cut greenhouse gas emissions by at least 25% within 5 years (by 2020), relative to 1990 levels. The case was filed on behalf of 886 Dutch citizens, suing the government for violating human rights and climate changes treaties by failing to take adequate action to prevent the harmful impacts of climate change. This judicial ruling has the potential to provide a way forward, inspiring other civil movements and creating a template from which to address other wicked problems. This judicial strategy to address the need to lower greenhouse gas emissions in the Netherlands is not a magic bullet, and requires a particular legal and institutional setting. However it has the potential to be a game-changer - providing an example of a strategy for achieving domestic regulatory change that is likely to be replicable in some countries elsewhere, and providing an example of a particularly 'wicked' (in the positive, street-slang sense of the word) strategy to address seemingly intractable and wicked problems.

90-Day Cycle Handbook

ERIC Educational Resources Information Center

Park, Sandra; Takahashi, Sola

2013-01-01

90-Day Cycles are a disciplined and structured form of inquiry designed to produce and test knowledge syntheses, prototyped processes, or products in support of improvement work. With any type of activity, organizations inevitably encounter roadblocks to improving performance and outcomes. These barriers might include intractable problems at…

Inaugural Technology Showcase Aims to Increase Industry Partnerships and Commercialization of Cancer-Related Inventions | FNLCR Staging

Cancer.gov

Biotechnology stakeholders from across the region will have the opportunity to learn about cutting-edge technologies addressing urgent and intractable problems in cancer research at the 2017 Technology Showcase, to be held at the Frederick National

Portfolios of quantum algorithms.

PubMed

Maurer, S M; Hogg, T; Huberman, B A

2001-12-17

Quantum computation holds promise for the solution of many intractable problems. However, since many quantum algorithms are stochastic in nature they can find the solution of hard problems only probabilistically. Thus the efficiency of the algorithms has to be characterized by both the expected time to completion and the associated variance. In order to minimize both the running time and its uncertainty, we show that portfolios of quantum algorithms analogous to those of finance can outperform single algorithms when applied to the NP-complete problems such as 3-satisfiability.

Pediatric epilepsy -- an Indian perspective.

PubMed

Udani, Vrajesh

2005-04-01

Prevalence studies from India suggest that epilepsy prevalence is similar to developed nations. Neurocysticercosis (NCC) predominates as an etiology. A large treatment gap is still a public health problem. Benign epilepsies and West syndrome appear to be underrepresented in studies on classification of seizures/syndromes. Febrile seizures prevalence in India is similar to other countries and appear to be as benign. Risk factors of intractable epilepsy (IE) in Indian studies include early age of onset, neurodevelopmental abnormalities and certain seizure types. Perinatal injuries underlie many IE. Many IE are not truly intractable and respond to simple therapeutic measures. The ketogenic diet and surgery are other methods now being used in Indian centers. Neurocysticercosis and neonatal hypoglycemic brain injury, two widely prevalent etiologies are reviewed in detail.

Pediatric epilepsy - an Indian perspective.

PubMed

Udani, Vrajesh

2005-04-01

Prevalence studies from India suggest that epilepsy prevalence is similar to developed nations. Neurocysticercosis (NCC) predominates as an etiology. A large treatment gap is still a public health problem. Benign epilepsies and West syndrome appear to be underrepresented in studies on classification of seizures/syndromes. Febrile seizures prevalence in India is similar to other countries and appear to be as benign. Risk factors of intractable epilepsy (IE) in Indian studies include early age of onset, neurodevelopmental abnormalities and certain seizure types. Perinatal injuries underlie many IE. Many IE are not truly intractable and respond to simple therapeutic measures. The ketogenic diet and surgery are other methods now being used in Indian centers. Neurocysticercosis and neonatal hypoglycemic brain injury, two widely prevalent etiologies are reviewed in detail.

Provable classically intractable sampling with measurement-based computation in constant time

NASA Astrophysics Data System (ADS)

Sanders, Stephen; Miller, Jacob; Miyake, Akimasa

We present a constant-time measurement-based quantum computation (MQC) protocol to perform a classically intractable sampling problem. We sample from the output probability distribution of a subclass of the instantaneous quantum polynomial time circuits introduced by Bremner, Montanaro and Shepherd. In contrast with the usual circuit model, our MQC implementation includes additional randomness due to byproduct operators associated with the computation. Despite this additional randomness we show that our sampling task cannot be efficiently simulated by a classical computer. We extend previous results to verify the quantum supremacy of our sampling protocol efficiently using only single-qubit Pauli measurements. Center for Quantum Information and Control, Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, USA.

The Quantum Measurement Problem and Physical reality: A Computation Theoretic Perspective

NASA Astrophysics Data System (ADS)

Srikanth, R.

2006-11-01

Is the universe computable? If yes, is it computationally a polynomial place? In standard quantum mechanics, which permits infinite parallelism and the infinitely precise specification of states, a negative answer to both questions is not ruled out. On the other hand, empirical evidence suggests that NP-complete problems are intractable in the physical world. Likewise, computational problems known to be algorithmically uncomputable do not seem to be computable by any physical means. We suggest that this close correspondence between the efficiency and power of abstract algorithms on the one hand, and physical computers on the other, finds a natural explanation if the universe is assumed to be algorithmic; that is, that physical reality is the product of discrete sub-physical information processing equivalent to the actions of a probabilistic Turing machine. This assumption can be reconciled with the observed exponentiality of quantum systems at microscopic scales, and the consequent possibility of implementing Shor's quantum polynomial time algorithm at that scale, provided the degree of superposition is intrinsically, finitely upper-bounded. If this bound is associated with the quantum-classical divide (the Heisenberg cut), a natural resolution to the quantum measurement problem arises. From this viewpoint, macroscopic classicality is an evidence that the universe is in BPP, and both questions raised above receive affirmative answers. A recently proposed computational model of quantum measurement, which relates the Heisenberg cut to the discreteness of Hilbert space, is briefly discussed. A connection to quantum gravity is noted. Our results are compatible with the philosophy that mathematical truths are independent of the laws of physics.

Supervised learning from human performance at the computationally hard problem of optimal traffic signal control on a network of junctions

PubMed Central

Box, Simon

2014-01-01

Optimal switching of traffic lights on a network of junctions is a computationally intractable problem. In this research, road traffic networks containing signallized junctions are simulated. A computer game interface is used to enable a human ‘player’ to control the traffic light settings on the junctions within the simulation. A supervised learning approach, based on simple neural network classifiers can be used to capture human player's strategies in the game and thus develop a human-trained machine control (HuTMaC) system that approaches human levels of performance. Experiments conducted within the simulation compare the performance of HuTMaC to two well-established traffic-responsive control systems that are widely deployed in the developed world and also to a temporal difference learning-based control method. In all experiments, HuTMaC outperforms the other control methods in terms of average delay and variance over delay. The conclusion is that these results add weight to the suggestion that HuTMaC may be a viable alternative, or supplemental method, to approximate optimization for some practical engineering control problems where the optimal strategy is computationally intractable. PMID:26064570

Supervised learning from human performance at the computationally hard problem of optimal traffic signal control on a network of junctions.

PubMed

Box, Simon

2014-12-01

Optimal switching of traffic lights on a network of junctions is a computationally intractable problem. In this research, road traffic networks containing signallized junctions are simulated. A computer game interface is used to enable a human 'player' to control the traffic light settings on the junctions within the simulation. A supervised learning approach, based on simple neural network classifiers can be used to capture human player's strategies in the game and thus develop a human-trained machine control (HuTMaC) system that approaches human levels of performance. Experiments conducted within the simulation compare the performance of HuTMaC to two well-established traffic-responsive control systems that are widely deployed in the developed world and also to a temporal difference learning-based control method. In all experiments, HuTMaC outperforms the other control methods in terms of average delay and variance over delay. The conclusion is that these results add weight to the suggestion that HuTMaC may be a viable alternative, or supplemental method, to approximate optimization for some practical engineering control problems where the optimal strategy is computationally intractable.

Why Universities Join Cross-Sector Social Partnerships: Theory and Evidence

ERIC Educational Resources Information Center

Siegel, David J.

2010-01-01

Cross-sector partnerships are an increasingly popular mode of organizing to address intractable social problems, yet theory and research have virtually ignored university involvement in such activity. This article attempts to ascertain the reasons universities join networks of other social actors to support a common cause. Theories on the…

Special Education Disproportionality: A Review of Response to Intervention and Culturally Relevant Pedagogy

ERIC Educational Resources Information Center

Cartledge, Gwendolyn; Kea, Cathy D.; Watson, Martreece; Oif, Alana

2016-01-01

Special education disproportionality for culturally and linguistically diverse (CLD) students persists as a controversial and intractable problem in our educational systems. Response to intervention (RtI) and culturally relevant pedagogy (CRP), both independently and collectively are considered to offer promise for mitigating conditions of…

LABORATORY EVALUATION OF ZERO-VALENT IRON TO TREAT GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

EPA Science Inventory

The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

Inaugural Technology Showcase Aims to Increase Industry Partnerships and Commercialization of Cancer-Related Inventions | Frederick National Laboratory for Cancer Research

Cancer.gov

Biotechnology stakeholders from across the region will have the opportunity to learn about cutting-edge technologies addressing urgent and intractable problems in cancer research at the 2017 Technology Showcase, to be held at the Frederick National

On Bayesian Testing of Additive Conjoint Measurement Axioms Using Synthetic Likelihood

ERIC Educational Resources Information Center

Karabatsos, George

2017-01-01

This article introduces a Bayesian method for testing the axioms of additive conjoint measurement. The method is based on an importance sampling algorithm that performs likelihood-free, approximate Bayesian inference using a synthetic likelihood to overcome the analytical intractability of this testing problem. This new method improves upon…

Temperature influences on diapause induction and survival in the boll weevil (Coleoptera: Curculionidae)

USDA-ARS?s Scientific Manuscript database

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), has been the most important pest of cotton (Gossypium spp.) wherever it occurs. Although eradication programs in the U.S. have reduced the range of this pest, the weevil remains an intractable problem in subtropical Tex...

Uncharted Territory: Can Social Innovation Revitalize Literacy and Essential Skills Programs?

ERIC Educational Resources Information Center

MacLaughlin, John; Samson, Ron

2013-01-01

The concept of social innovation has recently emerged as an influential approach to address intractable social problems. Increasingly discussed in academia and policy circles, the concept draws on multifaceted practices and ideas from many disciplines. Yet despite widespread discussion and promotion, there is still limited understanding of…

Enhancing Polyhedral Relaxations for Global Optimization

ERIC Educational Resources Information Center

Bao, Xiaowei

2009-01-01

During the last decade, global optimization has attracted a lot of attention due to the increased practical need for obtaining global solutions and the success in solving many global optimization problems that were previously considered intractable. In general, the central question of global optimization is to find an optimal solution to a given…

Backing in to the Foundations

ERIC Educational Resources Information Center

Quantz, Richard A.

2013-01-01

In this article, the author, after reviewing current educational trends, suggests that what really needs to happen is to "abandon education altogether." He contends that the worst problems of our times result from education, or, at least, what passes for education. The contemporary world's most intractable, most destructive, most…

An optimal repartitioning decision policy

NASA Technical Reports Server (NTRS)

Nicol, D. M.; Reynolds, P. F., Jr.

1986-01-01

A central problem to parallel processing is the determination of an effective partitioning of workload to processors. The effectiveness of any given partition is dependent on the stochastic nature of the workload. The problem of determining when and if the stochastic behavior of the workload has changed enough to warrant the calculation of a new partition is treated. The problem is modeled as a Markov decision process, and an optimal decision policy is derived. Quantification of this policy is usually intractable. A heuristic policy which performs nearly optimally is investigated empirically. The results suggest that the detection of change is the predominant issue in this problem.

Acute intractable vomiting and severe ketoacidosis secondary to the Dukan Diet©.

PubMed

Freeman, Thomas F; Willis, Blake; Krywko, Diann M

2014-10-01

The benefits of low-carbohydrate, high-protein diets, such as the Dukan Diet©, are well documented, whereas reported adverse effects are rare in literature. Such diets mimic starvation states in that they promote the breakdown of fat and the production of ketones secondary to fatty acid metabolism. In fact, one measure of the effectiveness of such diets is the presence of ketosis. To our knowledge, there have been no reported cases of ketoacidosis resulting from the Dukan Diet. The purpose of this case report is to illustrate the importance of a detailed dietary history in patients with severe ketoacidosis secondary to the Dukan Diet and suggest treatment that may allow outpatient management. A 42-year-old Iranian woman with no prior medical problems presented with 10 h of intractable nausea and vomiting secondary to ketoacidosis 2 days after starting the Dukan Diet. Although rare, ketoacidosis secondary to a low-carbohydrate, high-protein diet can have serious complications if untreated. Clinical suspicion should arise in any patient presenting with intractable nausea and vomiting after starting a diet such as the Dukan Diet. Early recognition and intervention is essential to quicken patient recovery and outpatient management. Published by Elsevier Inc.

Bayesian approach to inverse statistical mechanics.

PubMed

Habeck, Michael

2014-05-01

Inverse statistical mechanics aims to determine particle interactions from ensemble properties. This article looks at this inverse problem from a Bayesian perspective and discusses several statistical estimators to solve it. In addition, a sequential Monte Carlo algorithm is proposed that draws the interaction parameters from their posterior probability distribution. The posterior probability involves an intractable partition function that is estimated along with the interactions. The method is illustrated for inverse problems of varying complexity, including the estimation of a temperature, the inverse Ising problem, maximum entropy fitting, and the reconstruction of molecular interaction potentials.

Bayesian approach to inverse statistical mechanics

NASA Astrophysics Data System (ADS)

Habeck, Michael

2014-05-01

Inverse statistical mechanics aims to determine particle interactions from ensemble properties. This article looks at this inverse problem from a Bayesian perspective and discusses several statistical estimators to solve it. In addition, a sequential Monte Carlo algorithm is proposed that draws the interaction parameters from their posterior probability distribution. The posterior probability involves an intractable partition function that is estimated along with the interactions. The method is illustrated for inverse problems of varying complexity, including the estimation of a temperature, the inverse Ising problem, maximum entropy fitting, and the reconstruction of molecular interaction potentials.

Continuing Education as a National Capital Investment.

ERIC Educational Resources Information Center

Striner, Herbert E.

The constant readjustment that is necessary in a socially and economically complex society is discussed. The point is made that in recent years the United States has been confronted by an increasingly urgent series of economic problems. Intractably high levels of unemployment have accompanied abnormally high levels of inflation. It is also pointed…

How the Campus Crumbles: Colleges Face Challenges from Deferred Maintenance

ERIC Educational Resources Information Center

Carlson, Scott

2012-01-01

Many colleges have put off repairs and renovation since the recession. Now crumbling buildings, limited budgets, and mounting debt present an increasingly intractable problem. Sightlines, a consulting company that tracks and analyzes facilities issues at more than 300 colleges, shared some of its latest findings with "The Chronicle". The data…

Social Innovation Fund: Finding What Works, Making It Work for More People

ERIC Educational Resources Information Center

Corporation for National and Community Service, 2017

2017-01-01

The Social Innovation Fund (SIF), a program of the Corporation for National and Community Service (CNCS), supports the growth of effective programs, and the development of innovative approaches to solve the country's most intractable problems. The SIF directs resources towards efforts in the areas of youth development, economic opportunity, and…

Estimation of Complex Generalized Linear Mixed Models for Measurement and Growth

ERIC Educational Resources Information Center

Jeon, Minjeong

2012-01-01

Maximum likelihood (ML) estimation of generalized linear mixed models (GLMMs) is technically challenging because of the intractable likelihoods that involve high dimensional integrations over random effects. The problem is magnified when the random effects have a crossed design and thus the data cannot be reduced to small independent clusters. A…

From the bench to bedside to babies: translational medicine made possible by funding multidisciplinary team science.

PubMed

Woodruff, Teresa K

2013-10-01

In 2005, The National Institutes of Health (NIH) called upon the scientific community to identify the most intractable problems in science and medicine and describe how we would solve these problems using teams. Our group was one of 8 research communities awarded an 'interdisciplinary research consortium (IRC) grant.' Using the infrastructure of this large, multi-institute grant and a team science approach, we set out to solve the problem of fertility loss in young female cancer patients-work that was not easily funded through other mechanisms. The word 'oncofertility' was coined specifically for the IRC to reflect the intimate partnership between oncology care and fertility care for these patients-two disciplines that would no longer function at arms' length, but as an integrated unit. Catalyzed by the IRC funding mechanism, interdisciplinary teams worked together in unique ways to create a 'bench to bedside to baby' outcome. The grant has now ended, and remarkably, so have the most intractable parts of the original problem. As we look back on what worked and look forward to tackling the next set of fertility-related questions, we are confident that this very special NIH funding mechanism made a meaningful difference in the lives of women and their future children. NIH and the public would be well-served by supporting clinical problem-based, multidisciplinary team science approaches to catalyze fundamental biomedical breakthroughs and create new intellectual environments in which changes in clinical practice and standard of care can be implemented.

People efficiently explore the solution space of the computationally intractable traveling salesman problem to find near-optimal tours.

PubMed

Acuña, Daniel E; Parada, Víctor

2010-07-29

Humans need to solve computationally intractable problems such as visual search, categorization, and simultaneous learning and acting, yet an increasing body of evidence suggests that their solutions to instantiations of these problems are near optimal. Computational complexity advances an explanation to this apparent paradox: (1) only a small portion of instances of such problems are actually hard, and (2) successful heuristics exploit structural properties of the typical instance to selectively improve parts that are likely to be sub-optimal. We hypothesize that these two ideas largely account for the good performance of humans on computationally hard problems. We tested part of this hypothesis by studying the solutions of 28 participants to 28 instances of the Euclidean Traveling Salesman Problem (TSP). Participants were provided feedback on the cost of their solutions and were allowed unlimited solution attempts (trials). We found a significant improvement between the first and last trials and that solutions are significantly different from random tours that follow the convex hull and do not have self-crossings. More importantly, we found that participants modified their current better solutions in such a way that edges belonging to the optimal solution ("good" edges) were significantly more likely to stay than other edges ("bad" edges), a hallmark of structural exploitation. We found, however, that more trials harmed the participants' ability to tell good from bad edges, suggesting that after too many trials the participants "ran out of ideas." In sum, we provide the first demonstration of significant performance improvement on the TSP under repetition and feedback and evidence that human problem-solving may exploit the structure of hard problems paralleling behavior of state-of-the-art heuristics.

People Efficiently Explore the Solution Space of the Computationally Intractable Traveling Salesman Problem to Find Near-Optimal Tours

PubMed Central

Acuña, Daniel E.; Parada, Víctor

2010-01-01

Humans need to solve computationally intractable problems such as visual search, categorization, and simultaneous learning and acting, yet an increasing body of evidence suggests that their solutions to instantiations of these problems are near optimal. Computational complexity advances an explanation to this apparent paradox: (1) only a small portion of instances of such problems are actually hard, and (2) successful heuristics exploit structural properties of the typical instance to selectively improve parts that are likely to be sub-optimal. We hypothesize that these two ideas largely account for the good performance of humans on computationally hard problems. We tested part of this hypothesis by studying the solutions of 28 participants to 28 instances of the Euclidean Traveling Salesman Problem (TSP). Participants were provided feedback on the cost of their solutions and were allowed unlimited solution attempts (trials). We found a significant improvement between the first and last trials and that solutions are significantly different from random tours that follow the convex hull and do not have self-crossings. More importantly, we found that participants modified their current better solutions in such a way that edges belonging to the optimal solution (“good” edges) were significantly more likely to stay than other edges (“bad” edges), a hallmark of structural exploitation. We found, however, that more trials harmed the participants' ability to tell good from bad edges, suggesting that after too many trials the participants “ran out of ideas.” In sum, we provide the first demonstration of significant performance improvement on the TSP under repetition and feedback and evidence that human problem-solving may exploit the structure of hard problems paralleling behavior of state-of-the-art heuristics. PMID:20686597

Stigma and quality of life at long-term follow-up after surgery for epilepsy in Uganda.

PubMed

Fletcher, Anita; Sims-Williams, Helen; Wabulya, Angela; Boling, Warren

2015-11-01

Epilepsy is a worldwide health problem with a 10-fold greater prevalence in the developing world. Commonly, the seizure focus is in the temporal lobe, and seizures in about 30% of people with epilepsy are intractable to medication. For these individuals, surgery for intractable temporal lobe epilepsy (iTLE) is more effective than medication alone and may be the only option for cure. Intractable temporal lobe epilepsy is associated with elevated morbidity and mortality, reduced quality of life (QOL), and associated stigma particularly occurring in the developing world. Individuals with intractable epilepsy who participated in an earlier Uganda pilot study were selected for the current study based on their undergoing previous surgery for iTLE or having comparable seizure type who did not have surgery. At long-term follow-up, 10 who underwent surgery for iTLE in addition to 9 patients with focal dyscognitive type epilepsy who did not have surgery were evaluated in the current study. Tests were administered to look at various outcome parameters: seizure severity, QOL, stigma, and self-esteem. Stigma and self-esteem were additionally evaluated in the parent/caregiver. Seventy-percent of surgical resection patients were seizure-free at 8 years postsurgery. The QOLIE-31 scores were higher in surgical patients. Child/patient and parent/proxy surveys identified lower stigma in seizure-free patients. The results suggest that surgery for iTLE is an effective treatment for epilepsy in the developing world and provides an opportunity to reduce stigma and improve QOL. Copyright © 2015 Elsevier Inc. All rights reserved.

The intractable cigarette 'filter problem'.

PubMed

Harris, Bradford

2011-05-01

When lung cancer fears emerged in the 1950s, cigarette companies initiated a shift in cigarette design from unfiltered to filtered cigarettes. Both the ineffectiveness of cigarette filters and the tobacco industry's misleading marketing of the benefits of filtered cigarettes have been well documented. However, during the 1950s and 1960s, American cigarette companies spent millions of dollars to solve what the industry identified as the 'filter problem'. These extensive filter research and development efforts suggest a phase of genuine optimism among cigarette designers that cigarette filters could be engineered to mitigate the health hazards of smoking. This paper explores the early history of cigarette filter research and development in order to elucidate why and when seemingly sincere filter engineering efforts devolved into manipulations in cigarette design to sustain cigarette marketing and mitigate consumers' concerns about the health consequences of smoking. Relevant word and phrase searches were conducted in the Legacy Tobacco Documents Library online database, Google Patents, and media and medical databases including ProQuest, JSTOR, Medline and PubMed. 13 tobacco industry documents were identified that track prominent developments involved in what the industry referred to as the 'filter problem'. These reveal a period of intense focus on the 'filter problem' that persisted from the mid-1950s to the mid-1960s, featuring collaborations between cigarette producers and large American chemical and textile companies to develop effective filters. In addition, the documents reveal how cigarette filter researchers' growing scientific knowledge of smoke chemistry led to increasing recognition that filters were unlikely to offer significant health protection. One of the primary concerns of cigarette producers was to design cigarette filters that could be economically incorporated into the massive scale of cigarette production. The synthetic plastic cellulose acetate became the fundamental cigarette filter material. By the mid-1960s, the meaning of the phrase 'filter problem' changed, such that the effort to develop effective filters became a campaign to market cigarette designs that would sustain the myth of cigarette filter efficacy. This study indicates that cigarette designers at Philip Morris, British-American Tobacco, Lorillard and other companies believed for a time that they might be able to reduce some of the most dangerous substances in mainstream smoke through advanced engineering of filter tips. In their attempts to accomplish this, they developed the now ubiquitous cellulose acetate cigarette filter. By the mid-1960s cigarette designers realised that the intractability of the 'filter problem' derived from a simple fact: that which is harmful in mainstream smoke and that which provides the smoker with 'satisfaction' are essentially one and the same. Only in the wake of this realisation did the agenda of cigarette designers appear to transition away from mitigating the health hazards of smoking and towards the perpetuation of the notion that cigarette filters are effective in reducing these hazards. Filters became a marketing tool, designed to keep and recruit smokers as consumers of these hazardous products.

The Self-Organizing Psyche: Nonlinear and Neurobiological Contributions to Psychoanalysis

NASA Astrophysics Data System (ADS)

Stein, A. H.

Sigmund Freud attempted to align nineteenth century biology (and the dynamically conservative, continuous, Newtonian mechanics that underlie it) with discontinuous conscious experience. His tactics both set the future course for psychoanalytic development and introduced seemingly intractable complications into its metapsychology. In large part, these arose from what we now recognize were biological errors and dynamical oversimplifications amid his physical assumptions. Their correction, brought about by integrating nonlinear dynamics and neuro-biological research findings with W. Bion's reading of metapsychology, fundamentally supports a psychoanalysis based upon D. W. Winnicott's ideas surrounding play within transitional space.

A Localized Ensemble Kalman Smoother

NASA Technical Reports Server (NTRS)

Butala, Mark D.

2012-01-01

Numerous geophysical inverse problems prove difficult because the available measurements are indirectly related to the underlying unknown dynamic state and the physics governing the system may involve imperfect models or unobserved parameters. Data assimilation addresses these difficulties by combining the measurements and physical knowledge. The main challenge in such problems usually involves their high dimensionality and the standard statistical methods prove computationally intractable. This paper develops and addresses the theoretical convergence of a new high-dimensional Monte-Carlo approach called the localized ensemble Kalman smoother.

Linearly Adjustable International Portfolios

NASA Astrophysics Data System (ADS)

Fonseca, R. J.; Kuhn, D.; Rustem, B.

2010-09-01

We present an approach to multi-stage international portfolio optimization based on the imposition of a linear structure on the recourse decisions. Multiperiod decision problems are traditionally formulated as stochastic programs. Scenario tree based solutions however can become intractable as the number of stages increases. By restricting the space of decision policies to linear rules, we obtain a conservative tractable approximation to the original problem. Local asset prices and foreign exchange rates are modelled separately, which allows for a direct measure of their impact on the final portfolio value.

The continuum fusion theory of signal detection applied to a bi-modal fusion problem

NASA Astrophysics Data System (ADS)

Schaum, A.

2011-05-01

A new formalism has been developed that produces detection algorithms for model-based problems, in which one or more parameter values is unknown. Continuum Fusion can be used to generate different flavors of algorithm for any composite hypothesis testing problem. The methodology is defined by a fusion logic that can be translated into max/min conditions. Here it is applied to a simple sensor fusion model, but one for which the generalized likelihood ratio test is intractable. By contrast, a fusion-based response to the same problem can be devised that is solvable in closed form and represents a good approximation to the GLR test.

Poverty and Serious Mental Illness: Toward Action on a Seemingly Intractable Problem.

PubMed

Sylvestre, John; Notten, Geranda; Kerman, Nick; Polillo, Alexia; Czechowki, Konrad

2018-03-01

This paper examines the issue of poverty among people with serious mental illness (SMI), positioning it as a key issue to be confronted by community mental health systems and practitioners. The paper reviews three perspectives on poverty, considering how each sheds light on poverty among people with SMI, and their implications for action: (a) monetary resources, (b) basic needs, and (c) capabilities. The paper argues that community mental health programs and systems are currently unable to address poverty as they are overly focused on individual-level interventions that, on their own, cannot raise people out of poverty. The paper calls for a social justice value, informed by the concept of citizenship, as a necessary complement to the recovery concept that has informed community mental health practice for almost 25 years. Finally, the paper argues that community psychologists, with their concepts, methods, and values, are well positioned to contribute to this important issue. However, it also contends that addressing poverty requires collaboration from community psychologists with researchers and practitioners from other fields and domains of expertise to begin to make progress. © Society for Community Research and Action 2017.

Risk factor analysis and prevention of postoperative pancreatic fistula after distal pancreatectomy with stapler use.

PubMed

Sugimoto, Motokazu; Gotohda, Naoto; Kato, Yuichiro; Takahashi, Shinichiro; Kinoshita, Takahiro; Shibasaki, Hidehito; Nomura, Shogo; Konishi, Masaru; Kaneko, Hironori

2013-06-01

Postoperative pancreatic fistula (POPF) is a major, intractable complication after distal pancreatectomy (DP). Risk factor evaluation and prevention of this complication are important tasks for pancreatic surgeons. One hundred and six patients who underwent DP using a stapler for pancreatic division were retrospectively investigated. The relationship between clinicopathological factors and the incidence of POPF was statistically analyzed. Clinically relevant, Grade B or C POPF by International Study Group of Pancreatic Fistula criteria occurred in 52 patients (49.1 %). Age, American Society of Anesthesiologists score, body mass index, and concomitant gastrointestinal tract resection did not influence the incidence of POPF. Use of a double-row stapler and a thick pancreatic stump were significant risk factors for POPF in multivariate analysis. Compression index was also shown to be an important factor in cases in which the pancreas was divided by a stapler. The most important risk factor for POPF after DP was suggested to be the thickness of the pancreatic stump, reflecting the volume of remnant pancreas. A triple-row stapler seemed to be superior to a double-row stapler in preventing POPF. However, triple-row stapler use in a thick pancreas is considered to be a future problem to be solved.

Some Issues in Rural Education: Equity, Efficiency and Employment. IIEP Seminar Paper: 24.

ERIC Educational Resources Information Center

Colclough, C.; Hallak, J.

Recommendations for a new emphasis in rural education have arisen out of what is seen as a crisis in education itself and an awareness of the intractabilities of the unemployment problem for youth, urban, and educated populations. Basic education (defined as programs designed to teach primarily rural children and youth the basic knowledge…

Experimental Physical Sciences Vitae 2017

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kippen, Karen Elizabeth; Del Mauro, Diana; Patterson, Eileen Frances

Frequently our most basic research experiments stimulate solutions for some of the most intractable national security problems, such as nuclear weapons stewardship, homeland security, intelligence and information analysis, and nuclear and alternative energy. This publication highlights our talented and creative staff who deliver solutions to these complex scientific and technological challenges by conducting cutting-edge multidisciplinary physical science research.

Evolution and Revolution in China's Skill Formation System

ERIC Educational Resources Information Center

Xu, Jing

2011-01-01

This article outlines the current problems facing vocational education in China in order to raise the question as to how deep-seated and intractable they might be. In order to address this question a historical analysis of vocational education from the turn of the twentieth century to the end of Mao's period of office is undertaken. The rise of…

The Educator Needs to Be Educated: Reflections on the Political Pedagogy of Marx, Lenin and Habermas

ERIC Educational Resources Information Center

Welton, Michael R.

2014-01-01

This essay examines one of the most intractable pedagogical problems of the Marxian revolutionary tradition: who will educate the educator and how ought the learning process to proceed. The solutions of Marx, Lenin and Habermas are critically examined towards the clarification of the emancipatory learning process. This learning process has three…

Inaugural Technology Transfer Showcase Aims to Increase Industry Partnerships and Commercialization of Cancer-Related Inventions | Poster

Cancer.gov

Science and business professionals from across the region will have an opportunity to learn about—and perhaps even commercialize—cutting-edge technologies being used to address some of the most urgent and intractable problems in the biomedical sciences at an upcoming event held at the Frederick National Laboratory for Cancer Research.

Wildfire risk as a socioecological pathology

Treesearch

A Paige Fischer; Thomas A Spies; Toddi A Steelman; Cassandra Moseley; Bart R Johnson; John D Bailey; Alan A Ager; Patrick Bourgeron; Susan Charnley; Brandon M Collins; Jeff Kline; Jessica E Leahy; Jeremy S Littell; James DA Millington; Max Nielsen-Pincus; Christine S Olsen; Travis B Paveglio; Christopher I Roos; Michelle M Steen-Adams; Forrest R Stevens; Jelena Vukomanovic; Eric White; David MJS Bowman

2016-01-01

Wildfire risk in temperate forests has become a nearly intractable problem that can be characterized as a socioecological “pathology”: that is, a set of complex and problematic interactions among social and ecological systems across multiple spatial and temporal scales. Assessments of wildfire risk could benefit from recognizing and accounting for these interactions in...

Uncharted Territory: Can Social Innovation Revitalize Literacy and Essential Skills Programs? Research Brief

ERIC Educational Resources Information Center

MacLaughlin, John; Samson, Ron

2013-01-01

"Social innovation" has become a buzzword in social policy circles over the past decade and the concept of social innovation has emerged as an influential approach to address intractable social problems. Yet despite widespread discussion and promotion, there is still limited understanding of precisely what the concept means in terms of…

Neural-Network Computer Transforms Coordinates

NASA Technical Reports Server (NTRS)

Josin, Gary M.

1990-01-01

Numerical simulation demonstrated ability of conceptual neural-network computer to generalize what it has "learned" from few examples. Ability to generalize achieved with even simple neural network (relatively few neurons) and after exposure of network to only few "training" examples. Ability to obtain fairly accurate mappings after only few training examples used to provide solutions to otherwise intractable mapping problems.

Needs Assessment in STEM Disciplines: Reliability, Validity and Factor Structure of the Student Support Needs Scale (SSNS)

ERIC Educational Resources Information Center

Hardy, Precious; Aruguete, Mara

2014-01-01

Retention is a major problem in most colleges and universities. High dropout rates, especially in the STEM disciplines (science, technology, engineering and mathematics), have proved intractable despite the offering of supplemental instruction. A broad model of support systems that includes psychological factors is needed to address retention in…

Teaching for a Safer World: Lessons from the World Peace Game

ERIC Educational Resources Information Center

Baker, Jamie Feild; Hunter, John

2013-01-01

In an era of unprecedented volatility, ambiguity, impassioned conflict, and intractable problems that affect the basic living conditions and prosperity of many, education has never been more important or more in need of purpose, meaning, and applicability. The solutions to the dilemmas that define our world will be created and implemented in the…

Sustainability of Our Planet and All Species as the Organizing Principle for SLCE

ERIC Educational Resources Information Center

Kecskes, Kevin; Joyalle, Jennifer; Elliott, Erin; Sherman, Jacob D. B.

2017-01-01

We may define and prioritize them differently, but few would deny that our human community is facing intractable problems at local, national, and global scales. The authors call on higher education institutions (HEIs) around the world to work collectively and with strategic intent and action to use sustainability as an organizing principle to…

Single-port videoscopic splanchnotomy for palliation of refractory chronic pancreatitis.

PubMed

Kuijpers, Michiel; Klinkenberg, Theo J; Bouma, Wobbe; Beese, Ulrich; DeJongste, Mike J; Mariani, Massimo A

2016-04-01

Interrupting the afferent signals that travel through the splanchnic nerves by multiportal thoracoscopic splanchnotomy can offer effective palliation in chronic pancreatitis. However, obtained results weaken after time, possibly necessitating repeat procedures. Given the palliative nature of this procedure, potential for iatrogenic damage should be kept at a minimum. So, in order to minimize invasiveness while optimizing repeatability, we sought to create an easily reproducible single-access port operative strategy. Four patients suffering from intractable pain due to chronic pancreatitis for >10 years (12.8 ± 5.9) underwent a single-port unilateral R5-R11 splanchnotomy. Postoperative recovery was uneventful. No operative complications were observed. All 4 patients experienced excellent pain relief with a significant improvement of Visual Analogue Scale pain scores (8.8 ± 1.0 preoperatively to 3.0 ± 1.2 postoperatively, P = 0.003). We report the first series of single-port video-assisted thoracoscopic surgical (VATS) splanchnotomy for palliation of intractable pain due to chronic pancreatitis. From this small study, single-port VATS splanchnotomy seems to be a safe and effective alternative to multiportal or open procedures. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Intravenous Lidocaine: Old-School Drug, New Purpose—Reduction of Intractable Pain in Patients with Chemotherapy Induced Peripheral Neuropathy

PubMed Central

van der Wal, Selina E. I.; Smedes, Lotte A.; Radema, Sandra A.; van Alfen, Nens; Steegers, Monique A. H.

2017-01-01

Background. Treatment of intractable pain due to chemotherapy induced peripheral neuropathy (CIPN) is a challenge. Intravenous (iv) lidocaine has shown to be a treatment option for neuropathic pain of different etiologies. Methods. Lidocaine (1.5 mg/kg in 10 minutes followed by 1.5 mg/kg/h over 5 hours) was administered in nine patients with CIPN, and analgesic effect was evaluated during infusion and after discharge. The immediate effect of lidocaine on pressure pain thresholds (PPT) and the extent of the stocking and glove distribution of sensory abnormalities (cold and pinprick) were assessed. Results. Lidocaine had a significant direct analgesic effect in 8 out of 9 patients (P = 0.01) with a pain intensity difference of >30%. Pain reduction persisted in 5 patients for an average of 23 days. Lidocaine did not influence mean PPT, but there was a tendency that the extent of sensory abnormalities decreased after lidocaine. Conclusion. Iv lidocaine has direct analgesic effect in CIPN with a moderate long-term effect and seems to influence the area of cold and pinprick perception. Additional research is needed, using a control group and larger sample sizes to confirm these results. PMID:28458593

Epilepsy surgery in patients with malformations of cortical development.

PubMed

Lüders, Hans; Schuele, Stephan U

2006-04-01

Patients with malformations of cortical development often suffer from intractable focal epilepsy. This review considers recent progress in the selection and seizure outcome of patients undergoing resective epilepsy surgery for this condition. Patients with malformations of cortical development restricted to part or even a whole hemisphere may be candidates for epilepsy surgery even when, due to microscopic malformations, magnetic resonance imaging shows no detectable lesion. Despite recent advances in structural and functional imaging, the majority of patients with this condition undergo invasive evaluation. Patients with focal cortical dysplasia, with and without a detectable lesion on magnetic resonance imaging, often have a favorable outcome with epilepsy surgery. The underlying pathological substrate seems to be a better predictor for surgical outcome in patients with focal cortical dysplasia than the presence of a lesion on magnetic resonance imaging. Epilepsy surgery can be offered in a highly selected subgroup of patients with unilateral nodular heterotopia. Seizures in hemimegalencephaly may respond favorably to hemispherectomy, although most children will continue to have seizures and significant functional impairments. Patients with focal epilepsy due to malformations of cortical development are often intractable to medical management. Resective epilepsy surgery can be beneficial, particularly for patients with focal cortical dysplasia and unilateral hemispheric malformations.

Electrical or repetitive transcranial magnetic stimulation of primary motor cortex for intractable neuropathic pain.

PubMed

Saitoh, Youichi; Maruo, Tomoyuki; Yokoe, Masaru; Matsuzaki, Taiga; Sekino, Masaki

2013-01-01

To assess the pain-relieving effects of motor cortex electrical stimulation (MCS) and the predictive factors retrospectively. Thirty-four patients with intractable neuropathic pain underwent MCS; 19 patients had cerebral lesions, and 15 had non-cerebral lesions. In selected 12 patients, test electrodes were implanted within the central sulcus and on the precentral gyrus. Twelve patients received both MCS and repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex. Pain reduction of >50% was observed in 12 of 32 (36%) patients with >12 months follow-ups (2 patients were excluded because of short follow-up). In 10 of the 12 patients who received test electrodes within the central sulcus and on the precentral gyrus, the optimal stimulation was MCS within the central sulcus. In 4 of these (40%) patients, positive effects were maintained at follow-ups. The pain reduction of rTMS significantly correlated with that of MCS during test stimulation. The test stimulation within the central sulcus was more effective than that of the precentral gyrus. In the selected patients, chronic stimulation within the central sulcus did not significantly improve long-term results. Repeated rTMS seems to be same effective as MCS.

Seizure frequency reduction after posteromedial hypothalamus deep brain stimulation in drug-resistant epilepsy associated with intractable aggressive behavior.

PubMed

Benedetti-Isaac, Juan C; Torres-Zambrano, Martin; Vargas-Toscano, Andres; Perea-Castro, Esther; Alcalá-Cerra, Gabriel; Furlanetti, Luciano L; Reithmeier, Thomas; Tierney, Travis S; Anastasopoulos, Constantin; Fonoff, Erich T; Contreras Lopez, William Omar

2015-07-01

The aim of this study was to analyze the impact of deep brain stimulation (DBS) of the posteromedial hypothalamus (pHyp) on seizure frequency in patients with drug-resistant epilepsy (DRE) associated with intractable aggressive behavior (IAB). Data were collected retrospectively from nine patients, who received bilateral stereotactic pHyp-DBS for the treatment of medically intractable aggressive behavior, focusing on five patients who also had DRE. All patients were treated at the Colombian Center and Foundation of Epilepsy and Neurological Diseases-FIRE (Chapter of the International Bureau for Epilepsy), in Cartagena de Indias, Colombia from 2010 to 2014. Each case was evaluated previously by the institutional ethical committee, assessing the impact of aggressive behavior on the patient's family and social life, the humanitarian aspects of preserving the safety and physical integrity of caregivers, and the need to prevent self-harm. Epilepsy improvement was measured by a monthly seizure reduction percentage, comparing preoperative state and outcome. Additional response to epilepsy was defined by reduction of the antiepileptic drugs (AEDs). Aggressive behavior response was measured using the Overt Aggression Scale (OAS). All the patients with DRE associated with IAB presented a significant decrease of the rate of epileptic seizures after up to 4 years follow-up, achieving a general 89.6% average seizure reduction from the state before the surgery. Aggressiveness was significantly controlled, with evident improvement in the OAS, enhancing the quality of life of patients and families. In well-selected patients, DBS of the pHyp seems to be a safe and effective procedure for treatment of DRE associated with refractory aggressive behavior. Larger and prospective series are needed to define the pHyp as a target for DRE in different contexts. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

Root diseases: primary agents and secondary consequences of disturbance

Treesearch

William J. Otrosina; George T. Ferrell

1995-01-01

The fact that endemic root disease causing pathogens have evolved with forest ecosystems does not necessarily mean they are inconsequential. A pathogen such as the P group of Heterobasidion annosum has become an intractable problem in many Sierra east side pine stands in California because the fungus is adapted to colonization of freshly cut stump surfaces. The S group...

Response to Electroconvulsive Therapy in Patients With Autism Spectrum Disorder and Intractable Challenging Behaviors Associated With Symptoms of Catatonia.

PubMed

Sajith, Sreedharan Geetha; Liew, Siew Fai; Tor, Phern Chern

2017-03-01

There are several reports of electroconvulsive therapy (ECT) used in autism spectrum disorder (ASD) in the context of catatonic symptoms. We describe response to ECT in two adults with ASD and intellectual disability with intractable aggression and self-injurious behaviors associated with catatonic symptoms who had not responded to standard interventions. Unilateral ECT at a frequency of 3 times a week was given followed by weekly maintenance ECT. Patients' catatonic symptoms included episodes of agitation and echophenomena. Electroconvulsive therapy resulted in significant improvement in their behavior problems but 1 patient relapsed when the ECT was discontinued or frequency of treatment reduced. The second patient required 2 courses of ECT before improvement which was maintained on weekly ECT. Electroconvulsive therapy could be a potentially beneficial intervention in patients with ASD and severe challenging behaviors associated with catatonic symptoms including agitated or excited forms of catatonia.

A predictive risk model for medical intractability in epilepsy.

PubMed

Huang, Lisu; Li, Shi; He, Dake; Bao, Weiqun; Li, Ling

2014-08-01

This study aimed to investigate early predictors (6 months after diagnosis) of medical intractability in epilepsy. All children <12 years of age having two or more unprovoked seizures 24 h apart at Xinhua Hospital between 1992 and 2006 were included. Medical intractability was defined as failure, due to lack of seizure control, of more than 2 antiepileptic drugs at maximum tolerated doses, with an average of more than 1 seizure per month for 24 months and no more than 3 consecutive months of seizure freedom during this interval. Univariate and multivariate logistic regression models were performed to determine the risk factors for developing medical intractability. Receiver operating characteristic curve was applied to fit the best compounded predictive model. A total of 649 patients were identified, out of which 119 (18%) met the study definition of intractable epilepsy at 2 years after diagnosis, and the rate of intractable epilepsy in patients with idiopathic syndromes was 12%. Multivariate logistic regression analysis revealed that neurodevelopmental delay, symptomatic etiology, partial seizures, and more than 10 seizures before diagnosis were significant and independent risk factors for intractable epilepsy. The best model to predict medical intractability in epilepsy comprised neurological physical abnormality, age at onset of epilepsy under 1 year, more than 10 seizures before diagnosis, and partial epilepsy, and the area under receiver operating characteristic curve was 0.7797. This model also fitted best in patients with idiopathic syndromes. A predictive model of medically intractable epilepsy composed of only four characteristics is established. This model is comparatively accurate and simple to apply clinically. Copyright © 2014 Elsevier Inc. All rights reserved.

Quantum Computing: Solving Complex Problems

ScienceCinema

DiVincenzo, David

2018-05-22

One of the motivating ideas of quantum computation was that there could be a new kind of machine that would solve hard problems in quantum mechanics. There has been significant progress towards the experimental realization of these machines (which I will review), but there are still many questions about how such a machine could solve computational problems of interest in quantum physics. New categorizations of the complexity of computational problems have now been invented to describe quantum simulation. The bad news is that some of these problems are believed to be intractable even on a quantum computer, falling into a quantum analog of the NP class. The good news is that there are many other new classifications of tractability that may apply to several situations of physical interest.

Poverty functions and the aged population.

PubMed

Owens, E W

1990-01-01

This article examines trends in poverty among the elderly in the United States from two perspectives. "First, we are interested in changes that took place in the magnitude, characteristics and incidence of poverty within this sector, as a result of the functioning of the economy as well as the poverty programme during the past decade. Our second primary objective is to present analytical models of the severity of poverty and use these models to describe techniques that might be employed in evaluating ways of alleviating poverty in one category of the aged poor where it seems most acute and most intractable, i.e. aged women living alone." excerpt

Shared direct memory access on the Explorer 2-LX

NASA Technical Reports Server (NTRS)

Musgrave, Jeffrey L.

1990-01-01

Advances in Expert System technology and Artificial Intelligence have provided a framework for applying automated Intelligence to the solution of problems which were generally perceived as intractable using more classical approaches. As a result, hybrid architectures and parallel processing capability have become more common in computing environments. The Texas Instruments Explorer II-LX is an example of a machine which combines a symbolic processing environment, and a computationally oriented environment in a single chassis for integrated problem solutions. This user's manual is an attempt to make these capabilities more accessible to a wider range of engineers and programmers with problems well suited to solution in such an environment.

Predictors of intractable childhood epilepsy.

PubMed

Seker Yilmaz, Berna; Okuyaz, Cetin; Komur, Mustafa

2013-01-01

Our study sought to identify early predictive factors of medically intractable childhood epilepsy. A cohort of epileptic children from the city of Mersin was retrospectively investigated. All patients received care from the same Department of Pediatric Neurology. The epileptic cohort was divided into a drug-responsive epilepsy group and an intractable epilepsy group. Intractable epilepsy is defined as continued seizures in children despite adequate therapy with two or more antiepileptic drugs for more than 18 months. Strong univariate association was observed between intractability and several factors: age of onset, high initial seizure frequency, symptomatic etiology, mixed seizure types, previous history of status epilepticus, febrile and neonatal seizures, mental and motor developmental delay, multiple seizures in 1 day, electroencephalogram abnormalities, magnetic resonance imaging findings, and specific epileptic syndromes. Logistic regression analysis revealed that a previous history of epilepticus status, abnormal electroencephalogram results, and multiple seizures in 1 day comprise independent predictors of medically intractable childhood epilepsy. We suggest that medical intractability in childhood epilepsy can be predicted by monitoring these factors. Along with early prediction, alternative therapies may be designed to provide patients better seizure control and quality of life. Copyright © 2013 Elsevier Inc. All rights reserved.

Increased self-transcendence in patients with intractable diseases.

PubMed

Iwamoto, Rie; Yamawaki, Niwako; Sato, Takeshi

2011-12-01

Patients with intractable disease require long-term treatment and experience repeated bouts of progressive symptoms and resolutions, which cause them severe suffering. The aim of this study was to elucidate the concepts of self-transcendence and subjective well-being in patients with intractable disease. Forty-four patients with intractable disease (men/women: 22/22) participated. The diseases of the participants were classified into five systems: (i) neural/muscle system; (ii) digestive system; (iii) immunity/blood system; (iv) visual system; and (v) bone/joint system. The controls were 1854 healthy individuals (men/women: 935/869). Participants completed the Self-Transcendence Scale (STS) and the Japanese version of the World Health Organization-Subjective Inventory. The Japanese version of the Mini-International Neuropsychiatric Interview was also used for the intractable disease group. Analysis of covariance found a significant increase in STS score among the intractable disease group (P < 0.001). Multiple regression analysis showed that the positive affect measured by the World Health Organization-Subjective Inventory showed the greatest effect on the STS score for the intractable disease group (β = 0.539, P < 0.001). As a life-changing experience, an intractable disease may influence an increase in self-transcendence. The results also showed that there was a strong correlation between self-transcendence and respondents' subjective well-being. Our results suggest that patients with life-changing intractable disease can have a high level of self-transcendence, which may lead them to regain mental well-being, and increase their psychological health even in situations that cause physical and mental suffering. © 2011 The Authors. Psychiatry and Clinical Neurosciences © 2011 Japanese Society of Psychiatry and Neurology.

Closure of laryngotracheal cavity and tracheostomy for intractable aspiration secondary to radiation encephalopathy or radiation damage of cranial nerve after radiotherapy of nasopharyngeal carcinoma.

PubMed

Qu, Shenhong; Su, Zhengzhong; He, Xiaoguang; Li, Min; Li, Tianying

2006-09-01

Closure of the laryngotracheal cavity and tracheostomy is especially suitable for intractable aspiration secondary to radiation encephalopathy or damage of cranial nerve after radiation for nasopharyngeal carcinoma (NPC). To investigate the clinical value, technique, indications and contraindications of closure of the laryngotracheal cavity and tracheostomy for intractable aspiration secondary to radiation encephalopathy (REP) or radiation damage of cranial nerve after radiotherapy of NPC. Thirty patients, suffering from intractable aspiration secondary to radiotherapy for nasopharyngeal carcinoma, were treated with closure of the laryngotracheal cavity and tracheostomy and were observed for at least 1 year. Intractable aspiration and dyspnea were completely eradicated in all patients. The quality of their life was greatly improved.

Ethnicity and Race: Creating Educational Opportunities around the Globe. International Advances in Education: Global Initiatives for Equity and Social Justice

ERIC Educational Resources Information Center

Brown, Elinor L., Ed.; Gibbons, Pamela E., Ed.

2011-01-01

This volume of Global Initiatives for Equity and Social Justice takes a resource perspective toward culture, ethnicity, and race. Its purpose is to foster global dialog about race and ethnicity, with an emphasis on sharing strategies and solutions. While one might view problems stemming from racial and ethnic differences as intractable, the book's…

Harnessing the Hidden Curriculum: A Four-Step Approach to Developing and Reinforcing Reflective Competencies in Medical Clinical Clerkship

ERIC Educational Resources Information Center

Holmes, Cheryl L.; Harris, Ilene B.; Schwartz, Alan J.; Regehr, Glenn

2015-01-01

Changing the culture of medicine through the education of medical students has been proposed as a solution to the intractable problems of our profession. Yet few have explored the issues associated with making students partners in this change. There is a powerful hidden curriculum that perpetuates not only desired attitudes and behaviors but also…

The business plan: an AR perspective.

PubMed

Hajny, Tom

2008-01-01

It is important to periodically reassess the environment and what we need to accomplish in the near-term (or mid- or long term). Our skills, insights, knowledge, and talents grow yearly and maybe, just maybe, problems that we thought were intractable are, indeed, solvable. Play with the idea of Mission Statement, Objectives, and Keys to Success to stir up your neurons to execute a plan of excellence.

Intrapericardial triamcinolone hexacetonide in the treatment of intractable uremic pericarditis in a child.

PubMed

Medani, C R; Ringel, R E

1988-01-01

Uremic pericarditis in children on chronic hemodialysis represents a difficult management problem, necessitating vigorous medical therapy and often surgical drainage of the pericardial effusion. Standard therapeutic approaches have met with limited success. The successful use of intrapericardial triamcinolone in a 10-year anephric boy on chronic dialysis is reported and accompanied by a description of the technique applied and literature review.

Proactive and Adaptive Decision Support Study (PDS)

DTIC Science & Technology

2014-12-09

situations diverge from known models. Note that identifying the mission is not an open -ended problem, and is consequently not intractable. The set of...Simulation ( BRIMS ) Conference, Amelia Island, FL, 2012. [9] L. P. Kaelbling, M. L. Littman, and A. R. Cassandra, “Planning and acting in partially...Simulation Conference ( BRIMS ), Sundance, Utah, 2011. PDS Study Final Report 15 Distribution Statement A. Approved for public release; distribution

The Contours of Inequality: The Links between Socio-Economic Status of Students and Other Variables at the University of Johannesburg

ERIC Educational Resources Information Center

van Zyl, André

2016-01-01

The low level of student success in South Africa is an intractable problem, with levels of success differing between the various groups that make up South African society. One of the major constraints influencing student success involves the socio-economic status (SES) of newly entering students. In the South African context, with its very high…

Intractable lung abscess successfully treated with cavernostomy and free omental plombage using microvascular surgery.

PubMed

Shimizu, Junzo; Arano, Yoshihiko; Adachi, Iwao; Ikeda, Chikako; Ishikawa, Norihiko; Ohtake, Hiroshi

2009-11-01

A 68-year-old man, complaining of fever and puriform sputum, was referred to our hospital. A giant abscess was detected in the upper lobe of the right lung. Percutaneous drainage of a lung abscess was carried out. When the pus collected was cultured, Candida was 1+ and Escherichia coli was 2+. Later, it became difficult to control the abscess by drainage, and cavernostomy was selected. The contents of the abscess cavity were removed, and the cavity was opened, followed by exchange of gauze every day. For 14 months after cavernostomy, once-weekly gauze exchange was continued at the outpatient clinic to clean the abscess cavity. Finally, the abscess was filled with a free greater omentum flap, accompanied by microvascular anastomosis. In this way, the intractable lung abscess was successfully cured. Conventionally, surgical treatment, particularly cavernostomy, has been applied only to limited cases when dealing with a lung abscess. Our experience with the present case suggests that surgical treatment, including cavernostomy as one option, should also be considered when dealing with lung abscesses resisting medical treatment and causing compromised respiratory function. To enable maximum utilization of the greater omental flap, which is available in only a limited amount, it seems useful to prepare and graft a free omental flap making use of microvascular surgery.

Rethinking Intractable Conflict: The Perspective of Dynamical Systems

ERIC Educational Resources Information Center

Vallacher, Robin R.; Coleman, Peter T.; Nowak, Andrzej; Bui-Wrzosinska, Lan

2010-01-01

Intractable conflicts are demoralizing. Beyond destabilizing the families, communities, or international regions in which they occur, they tend to perpetuate the very conditions of misery and hate that contributed to them in the first place. Although the common factors and processes associated with intractable conflicts have been identified…

It looks easy! Heuristics for combinatorial optimization problems.

PubMed

Chronicle, Edward P; MacGregor, James N; Ormerod, Thomas C; Burr, Alistair

2006-04-01

Human performance on instances of computationally intractable optimization problems, such as the travelling salesperson problem (TSP), can be excellent. We have proposed a boundary-following heuristic to account for this finding. We report three experiments with TSPs where the capacity to employ this heuristic was varied. In Experiment 1, participants free to use the heuristic produced solutions significantly closer to optimal than did those prevented from doing so. Experiments 2 and 3 together replicated this finding in larger problems and demonstrated that a potential confound had no effect. In all three experiments, performance was closely matched by a boundary-following model. The results implicate global rather than purely local processes. Humans may have access to simple, perceptually based, heuristics that are suited to some combinatorial optimization tasks.

Subacute and chronic electrical stimulation of the hippocampus on intractable temporal lobe seizures: preliminary report.

PubMed

Velasco, A L; Velasco, M; Velasco, F; Menes, D; Gordon, F; Rocha, L; Briones, M; Márquez, I

2000-01-01

Recent animal experiments show that the application of an electrical stimulus to the amygdala or hippocampus following the kindling stimulus produced a significant and long-lasting suppressive effect on this experimental model of epilepsy. This is a preliminary report on the development of a surgical neuromodulatory procedure by chronic electrical stimulation of the hippocampus (CHCS) for control of intractable temporal lobe seizures in patients in whom anterior temporal lobectomy is not advisable, i.e., patients with bilateral temporal foci or a unilateral focus spreading to surrounding cerebral regions of the dominant hemisphere. This work was divided in two main consecutive stages. In the first stage, we demonstrated that subacute hippocampal stimulation (SAHCS) blocks intractable temporal lobe epileptogenesis with no additional damage to the stimulated tissue, and in a second stage, we attempt to demonstrate that CHCS may produce a sustained, long-lasting antiepileptic condition without additional undesirable effects on language and memory. In addition, taking advantage of this unique and ethically permissible situation, we attempt to determine whether or not the antiepileptic effects of SAHCS and CHCS are due to inhibition of the stimulation of hippocampal tissue by means of a number of electrophysiological, single photon computed tomography (SPECT) perfusion, and autoradiographic techniques.SAHCS during 3-4 weeks prior to anterior temporal lobectomy applied to a critical area located either at the anterior Pes hippocampus close to the amygdala or at the parahippocampal gyrus close to the entorhinal cortex abolished clinical seizures and significantly decreased the number of interictal spikes at focus after 5-6 days. Microscopy analysis of the stimulated tissue showed no evident histopathological differences between stimulated vs. non-stimulated hippocampal tissues. Additionally, CHCS persistently blocked temporal lobe epileptogenesis for 3-4 months with no apparent additional undesirable effects on short memory. Also, inhibition of the stimulated hippocampus seems to be one of the possible mechanisms underlying the beneficial antiepileptic effects of SAHCS and CHCS. This was revealed by increased threshold and decreased duration of the afterdischarges induced by hippocampal stimulation, flattening of the hippocampal-evoked response recovery cycles, SPECT hypoperfusion of the hippocampal region, and increased hippocampal benzodiazepine receptor binding. Future studies increasing the number and time of follow-up of patients under hippocampal stimulation are necessary before considering CHCS a reliable procedure for controlling intractable temporal lobe seizures.

Underworld results as a triple (shopping list, posterior, priors)

NASA Astrophysics Data System (ADS)

Quenette, S. M.; Moresi, L. N.; Abramson, D.

2013-12-01

When studying long-term lithosphere deformation and other such large-scale, spatially distinct and behaviour rich problems, there is a natural trade-off between the meaning of a model, the observations used to validate the model and the ability to compute over this space. For example, many models of varying lithologies, rheological properties and underlying physics may reasonably match (or not match) observables. To compound this problem, each realisation is computationally intensive, requiring high resolution, algorithm tuning and code tuning to contemporary computer hardware. It is often intractable to use sampling based assimilation methods, but with better optimisation, the window of tractability becomes wider. The ultimate goal is to find a sweet-spot where a formal assimilation method is used, and where a model affines to observations. Its natural to think of this as an inverse problem, in which the underlying physics may be fixed and the rheological properties and possibly the lithologies themselves are unknown. What happens when we push this approach and treat some portion of the underlying physics as an unknown? At its extreme this is an intractable problem. However, there is an analogy here with how we develop software for these scientific problems. What happens when we treat the changing part of a largely complete code as an unknown, where the changes are working towards this sweet-spot? When posed as a Bayesian inverse problem the result is a triple - the model changes, the real priors and the real posterior. Not only does this give meaning to the process by which a code changes, it forms a mathematical bridge from an inverse problem to compiler optimisations given such changes. As a stepping stone example we show a regional scale heat flow model with constraining observations, and the inverse process including increasingly complexity in the software. The implementation uses Underworld-GT (Underworld plus research extras to import geology and export geothermic measures, etc). Underworld uses StGermain an early (partial) implementation of the theories described here.

Successful implementation of a wellness and tobacco cessation curriculum in psychosocial rehabilitation clubhouses

PubMed Central

2011-01-01

Background Tobacco remains a seemingly intractable problem for individuals living with severe and persistent mental illness. This study evaluated the implementation, technical assistance, and perceived impact of a model curriculum ("Learning About Healthy Living") to promote wellness and motivation to quit tobacco use in psychosocial rehabilitation clubhouses. Methods We used semi-structured interviews (n = 9) with clubhouse staff (n = 12) and a survey of participating clubhouse members (n = 271) in nine clubhouses. Results Fifty-eight percent of clubhouse participants completed surveys. Results showed tobacco users open to tobacco-free policies (62%) and perceiving more discussions about quitting tobacco with healthcare providers (69%). Analyses of staff interviews and member surveys revealed four key themes: (1) the curriculum was successfully implemented and appreciated; (2) technical assistance kept implementation on track; (3) adding wellness content and interactive components should enhance the curriculum; and, (4) the curriculum advanced other healthful policies and practices. Conclusions Mental health settings are important locations for implementing programs to address tobacco use. In this real-world implementation of a model curriculum in psychosocial rehabilitation clubhouses, the curriculum tested well, was feasible and well-received, and suggests potential impact on tobacco use outcomes. Revision, dissemination, and a randomized controlled trial evaluation of the model curriculum should now occur. PMID:21917179

Patient mobile telephone 'text' reminder: a novel way to reduce non-attendance at the ENT out-patient clinic.

PubMed

Geraghty, M; Glynn, F; Amin, M; Kinsella, J

2008-03-01

Non-attendance at out-patient clinics is a seemingly intractable problem, estimated to cost 65 pounds sterling (97 euros) per incident. This results in under-utilisation of resources and prolonged waiting lists. In an effort to reduce out-patient clinic non-attendance, our ENT department, in conjunction with the information and communication technology department, instigated the use of a mobile telephone short message service ('text') reminder, to be sent out to each patient three days prior to their out-patient clinic appointment. To audit non-attendance rates at ENT out-patient clinics following the introduction of a text reminder system. Retrospective review. Non-attendance at our institution's ENT out-patient clinics was audited, following introduction of a text message reminder system in August 2003. Rates of non-attendance were compared for the text message reminder group and a historical control group. Before the introduction of the text message reminder system, the mean rate of non-attendance was 33.6 per cent. Following the introduction of the system, the mean rate of non-attendance reduced to 22 per cent. Sending text message reminders is a simple and cost-effective way to improve non-attendance at ENT out-patient clinics.

Assessment of the Density of Suppression to Identify Risk of Intractable Diplopia in the United Kingdom.

PubMed

Newsham, David; O'Connor, Anna R

2016-06-01

Occlusion used to treat amblyopia towards the end of the developmental component of the critical period gives a risk of inducing intractable diplopia. In the United Kingdom, the density of suppression is assessed via the Sbisa/Bagolini filter bar, but there is very little research evidence to guide clinical practice or interpretation of the tests used. The aims of this study were to determine current practice and estimate the incidence of intractable diplopia following amblyopia treatment. Current practice and incidence of intractable diplopia following amblyopia were determined via a questionnaire distributed to head orthoptists in every eye department in the United Kingdom. The questionnaire explored testing and test conditions, interpretation of the test results, and cases of intractable diplopia over the last 5 years. There was considerable variation in clinical practice of the measurement of the density of suppression and interpretation of the results to guide the treatment of amblyopia. The minimum age of patients taking the test ranged from 2 to 8 years and the minimum filter considered still safe to continue treatment ranged from 4 to 17. It is estimated there were 24 cases of intractable diplopia over the last 5 years. The issue of intractable diplopia and amblyopia treatment is likely to become increasingly important as there appears to be greater plasticity and scope to treat amblyopia in teenagers and adults than was previously thought. Lack of knowledge of how to evaluate the risk may lead to more cases of intractable diplopia or alternatively treatment being withheld unnecessarily.

A new parallel DNA algorithm to solve the task scheduling problem based on inspired computational model.

PubMed

Wang, Zhaocai; Ji, Zuwen; Wang, Xiaoming; Wu, Tunhua; Huang, Wei

2017-12-01

As a promising approach to solve the computationally intractable problem, the method based on DNA computing is an emerging research area including mathematics, computer science and molecular biology. The task scheduling problem, as a well-known NP-complete problem, arranges n jobs to m individuals and finds the minimum execution time of last finished individual. In this paper, we use a biologically inspired computational model and describe a new parallel algorithm to solve the task scheduling problem by basic DNA molecular operations. In turn, we skillfully design flexible length DNA strands to represent elements of the allocation matrix, take appropriate biological experiment operations and get solutions of the task scheduling problem in proper length range with less than O(n 2 ) time complexity. Copyright © 2017. Published by Elsevier B.V.

Political Socialization of Young Children in Intractable Conflicts: Conception and Evidence

ERIC Educational Resources Information Center

Bar-Tal, Daniel; Diamond, Aurel Harrison; Nasie, Meytal

2017-01-01

This article examines the political socialization of young children who live under conditions of intractable conflict. We present four premises: First, we argue that, within the context of intractable conflict, political socialization begins earlier and faster than previously suspected, and is evident among young children. Second, we propose that…

A sterile-female technique proposed for control of Striga hermonthica and other intractable weeds: Advantages, shortcomings, and risk management

USDA-ARS?s Scientific Manuscript database

Weeds have posed intractable challenges to farmers since the dawn of agriculture. This article describes in detail a proposed control strategy based on the introduction of genes conferring female-sterility into the genomes of intractable target weeds. Spread of these genes through target populations...

An Application of a Multidimensional Extension of the Two-Parameter Logistic Latent Trait Model.

DTIC Science & Technology

1983-08-01

theory, models, technical issues, and applications. Review of Educational Research, 1978, 48, 467-510. Marco, G. L. Item characteristic curve...solutions to three intractable testing problems. Journal of Educational Measurement, 1977, 14, 139-160. McKinley, R. L. and Reckase, M. D. A successful...application of latent trait theory to tailored achievement testing (Research Report 80-1). Columbia: University of Missouri, Department of Educational

Defining Mindfulness by How Poorly I Think I Pay Attention during Everyday Awareness and Other Intractable Problems for Psychology's (Re)Invention of Mindfulness: Comment on Brown Et Al. (2011)

ERIC Educational Resources Information Center

Grossman, Paul

2011-01-01

The Buddhist construct of mindfulness is a central element of mindfulness-based interventions and derives from an age-old systematic phenomenological program to investigate subjective experience. Recent enthusiasm for "mindfulness" in psychology has resulted in proliferation of self-report inventories that purport to measure mindful awareness as a…

Reverse engineering of integrated circuits

DOEpatents

Chisholm, Gregory H.; Eckmann, Steven T.; Lain, Christopher M.; Veroff, Robert L.

2003-01-01

Software and a method therein to analyze circuits. The software comprises several tools, each of which perform particular functions in the Reverse Engineering process. The analyst, through a standard interface, directs each tool to the portion of the task to which it is most well suited, rendering previously intractable problems solvable. The tools are generally used iteratively to produce a successively more abstract picture of a circuit, about which incomplete a priori knowledge exists.

"To Obey or Disobey? This Is the Question" NDE: Nonviolent Disobedience Education in Israeli and US Civics Textbooks (1980-2012)

ERIC Educational Resources Information Center

Firer, Ruth

2013-01-01

"To Obey or Disobey" should be a life question for all free people, but for the Israelis, who are in intractable war with their neighbors while facing constant rifts among themselves, it is a concrete problem they have to face every day. Therefore, the research question posed by this article is: How is obedience of laws or military…

The Role of Brain Inflammation in Epileptogenesis in TSC

DTIC Science & Technology

2014-07-01

human temporal lobe epilepsy . Neurobiol Dis 2008;29:142-160. 5. Ravizza T, Noe F, Zardoni D, Vaghi V, Sifringer M, Vezzani A. Interleukin...of epilepsy , as well as in human tissue obtained from epilepsy patients, such as with mesial temporal sclerosis. Different types of inflammatory...14. ABSTRACT Epilepsy is a common, disabling problem in patients with tuberous sclerosis complex (TSC) and is usually intractable to available

Predictions of Crystal Structures from First Principles

DTIC Science & Technology

2007-06-01

RDX crystal in hoped that the problem could be resolved by the molecular dynamics simulations . The fully ab initio development of density functional... Molecular Dynamics Simulations of RDX i.e., without any use of experimental results (except that Crystal the geometry of monomers was derived from X-ray...applied in molecular dynamics simulations of the RDX system, due to its size, is intractable by any high-level ab crystal. We performed isothermal

Elucidating Reaction Mechanisms on Quantum Computers

NASA Astrophysics Data System (ADS)

Wiebe, Nathan; Reiher, Markus; Svore, Krysta; Wecker, Dave; Troyer, Matthias

We show how a quantum computer can be employed to elucidate reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example. We discuss how quantum computers can augment classical-computer simulations for such problems, to significantly increase their accuracy and enable hitherto intractable simulations. Detailed resource estimates show that, even when taking into account the substantial overhead of quantum error correction, and the need to compile into discrete gate sets, the necessary computations can be performed in reasonable time on small quantum computers. This demonstrates that quantum computers will realistically be able to tackle important problems in chemistry that are both scientifically and economically significant.

Predictors and Course of Medically Intractable Epilepsy in Young Children Presenting Before 36 Months of Age: A Retrospective, Population-Based Study

PubMed Central

Wirrell, Elaine; Wong-Kisiel, Lily; Mandrekar, Jay; Nickels, Katherine

2012-01-01

Purpose To determine the prevalence and identify predictors of medical intractability in children presenting with epilepsy prior to 36 months of age, and to assess the impact of medical intractability on long-term mortality and intellectual function. Methods Children with newly-diagnosed epilepsy prior to 36 months between 1980–2009 while resident in Olmsted County, MN were identified. Medical records were reviewed to collect epilepsy specific variables and long-term outcome data. Medically intractable epilepsy was defined as either (1) seizures greater than every 6 months at final follow-up and failure of two or more antiepileptic drugs for lack of efficacy, or (2) having undergone epilepsy surgery after failure of two or more antiepileptic drugs. Key Findings One hundred and twenty seven children with new-onset epilepsy were identified and followed for a median of 78 months. Medically intractable seizures occurred in 35%, and significant predictors on multivariate analysis were age ≤12 months at diagnosis (odds ratio [OR] 6.76, 95% confidence interval [CI] 2.00, 22.84, p=0.002), developmental delay at initial diagnosis of epilepsy (OR 20.03, 95% CI 3.49, 114.83, p=0.0008 ), neuroimaging abnormality (OR 6.48, 95% CI 1.96, 21.40, p=0.002) and focal slowing on initial EEG (OR 5.33, 95% CI 1.14, 24.88, p=0.03). Medical intractability occurred early in the course in most children, being seen in 61% by one year, and 93% by five years after initial diagnosis. Mortality was higher (20% vs 0%, p<0.001) and intellectual outcome poorer (p<0.001) if epilepsy was medically intractable. Significance One third of children presenting with epilepsy before 36 months will be medically intractable and significant predictors are identified. Medically intractable epilepsy is associated with increased mortality risk and significant intellectual disability. PMID:22738069

Ethics and radiation protection.

PubMed

Hansson, Sven Ove

2007-06-01

Some of the major problems in radiation protection are closely connected to issues that have a long, independent tradition in moral philosophy. This contribution focuses on two of these issues. One is the relationship between the protection of individuals and optimisation on the collective level, and the other is the relative valuation of future versus immediate damage. Some of the intellectual tools that have been developed by philosophers can be useful in radiation protection. On the other hand, philosophers have much to learn from radiation protectors, not least when it comes to finding pragmatic solutions to problems that may be intractable in principle.

Demonstration of essentiality of entanglement in a Deutsch-like quantum algorithm

NASA Astrophysics Data System (ADS)

Huang, He-Liang; Goswami, Ashutosh K.; Bao, Wan-Su; Panigrahi, Prasanta K.

2018-06-01

Quantum algorithms can be used to efficiently solve certain classically intractable problems by exploiting quantum parallelism. However, the effectiveness of quantum entanglement in quantum computing remains a question of debate. This study presents a new quantum algorithm that shows entanglement could provide advantages over both classical algorithms and quantum algo- rithms without entanglement. Experiments are implemented to demonstrate the proposed algorithm using superconducting qubits. Results show the viability of the algorithm and suggest that entanglement is essential in obtaining quantum speedup for certain problems in quantum computing. The study provides reliable and clear guidance for developing useful quantum algorithms.

Probabilistic models, learning algorithms, and response variability: sampling in cognitive development.

PubMed

Bonawitz, Elizabeth; Denison, Stephanie; Griffiths, Thomas L; Gopnik, Alison

2014-10-01

Although probabilistic models of cognitive development have become increasingly prevalent, one challenge is to account for how children might cope with a potentially vast number of possible hypotheses. We propose that children might address this problem by 'sampling' hypotheses from a probability distribution. We discuss empirical results demonstrating signatures of sampling, which offer an explanation for the variability of children's responses. The sampling hypothesis provides an algorithmic account of how children might address computationally intractable problems and suggests a way to make sense of their 'noisy' behavior. Copyright © 2014 Elsevier Ltd. All rights reserved.

Growth hormone used to control intractable bleeding caused by radiation-induced gastritis.

PubMed

Zhang, Liang; Xia, Wen-Jie; Zhang, Zheng-Sen; Lu, Xin-Liang

2015-08-21

Intractable bleeding caused by radiation-induced gastritis is rare. We describe a 69-year-old man with intractable hemorrhagic gastritis induced by postoperative radiotherapy for the treatment of esophageal carcinoma. Although anti-secretory therapy with or without octreotide was initiated for hemostasis over three months, melena still occurred off and on, and the patient required blood transfusions to maintain stable hemoglobin. Finally growth hormone was used in the treatment of hemorrhage for two weeks, and hemostasis was successfully achieved. This is the first report that growth hormone has been used to control intractable bleeding caused by radiation-induced gastritis.

Peace Education in Societies Involved in Intractable Conflicts: Direct and Indirect Models

ERIC Educational Resources Information Center

Bar-Tal, Daniel; Rosen, Yigal

2009-01-01

The present article deals with the crucial question: Can peace education facilitate change in the sociopsychological infrastructure that feeds continued intractable conflict and then how the change can be carried? Intractable conflicts still rage in various parts of the globe, and they not only cause local misery and suffering but also threaten…

Computing quantum discord is NP-complete

NASA Astrophysics Data System (ADS)

Huang, Yichen

2014-03-01

We study the computational complexity of quantum discord (a measure of quantum correlation beyond entanglement), and prove that computing quantum discord is NP-complete. Therefore, quantum discord is computationally intractable: the running time of any algorithm for computing quantum discord is believed to grow exponentially with the dimension of the Hilbert space so that computing quantum discord in a quantum system of moderate size is not possible in practice. As by-products, some entanglement measures (namely entanglement cost, entanglement of formation, relative entropy of entanglement, squashed entanglement, classical squashed entanglement, conditional entanglement of mutual information, and broadcast regularization of mutual information) and constrained Holevo capacity are NP-hard/NP-complete to compute. These complexity-theoretic results are directly applicable in common randomness distillation, quantum state merging, entanglement distillation, superdense coding, and quantum teleportation; they may offer significant insights into quantum information processing. Moreover, we prove the NP-completeness of two typical problems: linear optimization over classical states and detecting classical states in a convex set, providing evidence that working with classical states is generically computationally intractable.

Perceptions regarding a range of work-related issues and corresponding support needs of individuals with an intractable disease.

PubMed

Imahashi, Kumiko; Fukatsu, Reiko; Nakajima, Yasoichi; Nakamura, Megumi; Ito, Tateo; Horigome, Mariko; Haruna, Yuichiro; Noda, Tatsuya; Itoyama, Yasuto

2016-08-01

A number of persons with an intractable disease (ID) experience work-related problems that could lead to job loss. The aim of this study was to ascertain perceptions regarding a range of work-related issues and corresponding support needs of individuals with an ID. Potential participants were people ages 15 to 64 with one of the 130 intractable chronic diseases designated in the Act to Comprehensively Support the Daily and Social Activities of Persons with Disabilities (Comprehensive Support for the Disabled Act). Participants completed a self-administered questionnaire. With the assistance of patients' organizations, 3,000 questionnaires were mailed to potential participants. Questions included demographic characteristics, family concerns, employment/supported employment, work accommodations, and other aspects of life. Responses were received from 889 (29.6%) participants, and respondents had 57 IDs. Forty-six-point-seven percent of respondents reported being unemployed due to fatigue and/or long-term treatment. Nearly half of the unemployed respondents reported that they had been unable to work despite their willingness to do so. Common requests for accommodation included flexible work hours, working at home, and job/workplace modifications. Only 30% of respondents knew about job training programs and supported work available for persons with disabilities. The results of the study are relevant for employees, employers, and occupational health/human resource professionals. The issue of reasonable accommodations for persons with an ID needs to be addressed in future research in order to promote continued work by those persons.

Ship Structure Committee Long-Range Research Plan - Guidelines for Program Development.

DTIC Science & Technology

1982-01-01

many scientists and engineers who contributed their time and expertise. We are indebted especially to Mr. J. J. Hopkinson, Dr. J. G. Giannotti, Mr...projection is better than assuming extension of the status quo. There is a long lead time in the use of new knowledge. Scientific research maturation...They even promise to remove traditional constraints previously too intractable to be labelled problems. The modern computer is an outstanding example

Characteristics and safety assessment of intractable proteins in genetically modified crops.

PubMed

Bushey, Dean F; Bannon, Gary A; Delaney, Bryan F; Graser, Gerson; Hefford, Mary; Jiang, Xiaoxu; Lee, Thomas C; Madduri, Krishna M; Pariza, Michael; Privalle, Laura S; Ranjan, Rakesh; Saab-Rincon, Gloria; Schafer, Barry W; Thelen, Jay J; Zhang, John X Q; Harper, Marc S

2014-07-01

Genetically modified (GM) crops may contain newly expressed proteins that are described as "intractable". Safety assessment of these proteins may require some adaptations to the current assessment procedures. Intractable proteins are defined here as those proteins with properties that make it extremely difficult or impossible with current methods to express in heterologous systems; isolate, purify, or concentrate; quantify (due to low levels); demonstrate biological activity; or prove equivalency with plant proteins. Five classes of intractable proteins are discussed here: (1) membrane proteins, (2) signaling proteins, (3) transcription factors, (4) N-glycosylated proteins, and (5) resistance proteins (R-proteins, plant pathogen recognition proteins that activate innate immune responses). While the basic tiered weight-of-evidence approach for assessing the safety of GM crops proposed by the International Life Sciences Institute (ILSI) in 2008 is applicable to intractable proteins, new or modified methods may be required. For example, the first two steps in Tier I (hazard identification) analysis, gathering of applicable history of safe use (HOSU) information and bioinformatics analysis, do not require protein isolation. The extremely low level of expression of most intractable proteins should be taken into account while assessing safety of the intractable protein in GM crops. If Tier II (hazard characterization) analyses requiring animal feeding are judged to be necessary, alternatives to feeding high doses of pure protein may be needed. These alternatives are discussed here. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

SNF5 Mutation Leads to Intractable Pain in Schwannomatosis Patients

DTIC Science & Technology

2012-07-01

AD_________________ Award Number: W81XWH-11-1-0143 TITLE: SNF5 mutation leads to intractable pain in schwannomatosis patients...DATES COVERED 15-June-2011 to 14-June-2012 4. TITLE AND SUBTITLE SNF5 mutation leads to intractable pain in schwannomatosis patients 5a. CONTRACT...6 Introduction. Schwannomatosis does not affect longevity but it has profound effects on the patient’s quality of

Between universalism and relativism: a conceptual exploration of problems in formulating and applying international biomedical ethical guidelines.

PubMed

Tangwa, G B

2004-02-01

In this paper, the author attempts to explore some of the problems connected with the formulation and application of international biomedical ethical guidelines, with particular reference to Africa. Recent attempts at revising and updating some international medical ethical guidelines have been bedevilled by intractable controversies and wrangling regarding both the content and formulation. From the vantage position of relative familiarity with both African and Western contexts, and the privilege of having been involved in the revision and updating of one of the international ethical guidelines, the author reflects broadly on these issues and attempts prescribing an approach from both the theoretical and practical angles liable to mitigate, if not completely eliminate, some of the problems and difficulties.

Physical Feature Encoding and Word Recognition Abilities Are Altered in Children with Intractable Epilepsy: Preliminary Neuromagnetic Evidence

PubMed Central

Pardos, Maria; Korostenskaja, Milena; Xiang, Jing; Fujiwara, Hisako; Lee, Ki H.; Horn, Paul S.; Byars, Anna; Vannest, Jennifer; Wang, Yingying; Hemasilpin, Nat; Rose, Douglas F.

2015-01-01

Objective evaluation of language function is critical for children with intractable epilepsy under consideration for epilepsy surgery. The purpose of this preliminary study was to evaluate word recognition in children with intractable epilepsy by using magnetoencephalography (MEG). Ten children with intractable epilepsy (M/F 6/4, mean ± SD 13.4 ± 2.2 years) were matched on age and sex to healthy controls. Common nouns were presented simultaneously from visual and auditory sensory inputs in “match” and “mismatch” conditions. Neuromagnetic responses M1, M2, M3, M4, and M5 with latencies of ~100 ms, ~150 ms, ~250 ms, ~350 ms, and ~450 ms, respectively, elicited during the “match” condition were identified. Compared to healthy children, epilepsy patients had both significantly delayed latency of the M1 and reduced amplitudes of M3 and M5 responses. These results provide neurophysiologic evidence of altered word recognition in children with intractable epilepsy. PMID:26146459

Addressing homelessness among people with mental illnesses: a model of long-term philanthropic effectiveness.

PubMed

Brousseau, Ruth Tebbets

2009-01-01

Foundations are often criticized for their short attention spans and inability to continue funding the toughest social problems. Homelessness among people with mental illnesses is considered among the most intractable of social issues. This paper explores the role of permanent supportive housing in reducing homelessness among the mentally ill; the role of the Corporation for Supportive Housing in developing, authenticating, and disseminating its model; and its long-term funding relationship with the Conrad N. Hilton Foundation, which has facilitated this trajectory. The paper tells the story of how long-term funding, strategically used, is making inroads into this serious mental health problem.

Computing aggregate properties of preimages for 2D cellular automata.

PubMed

Beer, Randall D

2017-11-01

Computing properties of the set of precursors of a given configuration is a common problem underlying many important questions about cellular automata. Unfortunately, such computations quickly become intractable in dimension greater than one. This paper presents an algorithm-incremental aggregation-that can compute aggregate properties of the set of precursors exponentially faster than naïve approaches. The incremental aggregation algorithm is demonstrated on two problems from the two-dimensional binary Game of Life cellular automaton: precursor count distributions and higher-order mean field theory coefficients. In both cases, incremental aggregation allows us to obtain new results that were previously beyond reach.

Computing aggregate properties of preimages for 2D cellular automata

NASA Astrophysics Data System (ADS)

Beer, Randall D.

2017-11-01

Computing properties of the set of precursors of a given configuration is a common problem underlying many important questions about cellular automata. Unfortunately, such computations quickly become intractable in dimension greater than one. This paper presents an algorithm—incremental aggregation—that can compute aggregate properties of the set of precursors exponentially faster than naïve approaches. The incremental aggregation algorithm is demonstrated on two problems from the two-dimensional binary Game of Life cellular automaton: precursor count distributions and higher-order mean field theory coefficients. In both cases, incremental aggregation allows us to obtain new results that were previously beyond reach.

Nutrient intake of children with intractable epilepsy compared with healthy children.

PubMed

Volpe, Stella L; Schall, Joan I; Gallagher, Paul R; Stallings, Virginia A; Bergqvist, A G Christina

2007-06-01

Growth retardation is common among children with epilepsy, and poor dietary intake may be one of the causes. The goal of this cross-sectional study was to compare the nutrient intake of children 1 to 8 years of age with intractable epilepsy to healthy children of the same age from the National Health and Nutrition Examination Survey 2001 to 2002 (N=1,718) and with the Dietary Reference Intakes. Children with intractable epilepsy were divided into two age groups: 1.0 to 3.9 and 4.0 to 8.9 years, to correspond with the Dietary Reference Intakes. Forty-three children with intractable epilepsy, mean age=4.7+/-2.2 years, had significantly lower intakes (P<0.05) of total energy; protein; carbohydrate; fat; dietary fiber; vitamins A, E, B-6, and B-12; riboflavin; niacin; folate; calcium; phosphorus; magnesium; zinc; copper; and selenium compared with healthy children. Thirty percent or more of the children with intractable epilepsy in both age groups had intakes below the Recommended Dietary Allowance or Adequate Intake for vitamins D, E, and K; folate; calcium; linoleic acid; and alpha-linolenic acid. Health care professionals caring for children with intractable epilepsy should be aware of this pattern of decreased nutrient intake and educate families to provide an adequate diet and/or consider vitamin/mineral supplementation.

Designing environmental research for impact.

PubMed

Campbell, C A; Lefroy, E C; Caddy-Retalic, S; Bax, N; Doherty, P J; Douglas, M M; Johnson, D; Possingham, H P; Specht, A; Tarte, D; West, J

2015-11-15

Transdisciplinary research, involving close collaboration between researchers and the users of research, has been a feature of environmental problem solving for several decades, often spurred by the need to find negotiated outcomes to intractable problems. In 2005, the Australian government allocated funding to its environment portfolio for public good research, which resulted in consecutive four-year programmes (Commonwealth Environmental Research Facilities, National Environmental Research Program). In April 2014, representatives of the funders, researchers and research users associated with these programmes met to reflect on eight years of experience with these collaborative research models. This structured reflection concluded that successful multi-institutional transdisciplinary research is necessarily a joint enterprise between funding agencies, researchers and the end users of research. The design and governance of research programmes need to explicitly recognise shared accountabilities among the participants, while respecting the different perspectives of each group. Experience shows that traditional incentive systems for academic researchers, current trends in public sector management, and loose organisation of many end users, work against sustained transdisciplinary research on intractable problems, which require continuity and adaptive learning by all three parties. The likelihood of research influencing and improving environmental policy and management is maximised when researchers, funders and research users have shared goals; there is sufficient continuity of personnel to build trust and sustain dialogue throughout the research process from issue scoping to application of findings; and there is sufficient flexibility in the funding, structure and operation of transdisciplinary research initiatives to enable the enterprise to assimilate and respond to new knowledge and situations. Copyright © 2014 Elsevier B.V. All rights reserved.

Intractable seizures after a lengthy remission in childhood-onset epilepsy.

PubMed

Camfield, Peter R; Camfield, Carol S

2017-12-01

To establish the risk of subsequent intractable epilepsy after ≥2, ≥5, and ≥10 years of remission in childhood-onset epilepsy. From the Nova Scotia childhood-onset epilepsy population-based cohort patients with all types of epilepsy were selected with ≥20 years follow-up from seizure onset (incidence cases). Children with childhood absence epilepsy were excluded. The rate of subsequent intractable epilepsy was then studied for patients with ≥5 years remission on or off AED treatment and compared with the rate for those with ≥2 and ≥10 years of remission. Three hundred eighty-eight eligible patients had ≥20 years follow-up (average 27.7 ± (standard deviation) 4 years) until they were an average of 34 ± 6.5 years of age. Overall, 297 (77%) had a period of ≥5 years of seizure freedom (average 21.2 ± 8 years), with 90% of these remissions continuing to the end of follow-up. Seizures recurred in 31 (10%) and were intractable in 7 (2%). For the 332 with a remission of ≥2 years seizure-free, 6.9% subsequently developed intractable epilepsy (p = 0.001). For the 260 with ≥10 years remission, 0.78% subsequently developed intractable epilepsy (p = 0.25 compared with ≥5 years remission). Even after ≥5 or ≥10 years of seizure freedom, childhood-onset epilepsy may reappear and be intractable. The risk is fortunately small, but for most patients it is not possible to guarantee a permanent remission. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

Clairvoyant fusion: a new methodology for designing robust detection algorithms

NASA Astrophysics Data System (ADS)

Schaum, Alan

2016-10-01

Many realistic detection problems cannot be solved with simple statistical tests for known alternative probability models. Uncontrollable environmental conditions, imperfect sensors, and other uncertainties transform simple detection problems with likelihood ratio solutions into composite hypothesis (CH) testing problems. Recently many multi- and hyperspectral sensing CH problems have been addressed with a new approach. Clairvoyant fusion (CF) integrates the optimal detectors ("clairvoyants") associated with every unspecified value of the parameters appearing in a detection model. For problems with discrete parameter values, logical rules emerge for combining the decisions of the associated clairvoyants. For many problems with continuous parameters, analytic methods of CF have been found that produce closed-form solutions-or approximations for intractable problems. Here the principals of CF are reviewed and mathematical insights are described that have proven useful in the derivation of solutions. It is also shown how a second-stage fusion procedure can be used to create theoretically superior detection algorithms for ALL discrete parameter problems.

Interictal spike detection comparing subdural and depth electrodes during electrocorticography.

PubMed

Privitera, M D; Quinlan, J G; Yeh, H S

1990-11-01

We compared the ability of subdural and depth electrodes to detect and localize interictal epileptiform discharges (IEDs) in the temporal lobe. Sixteen patients had simultaneous intraoperative recordings with depth and subdural electrodes while undergoing anterior temporal lobe resections under local anesthesia for medically intractable seizures. IEDs that were focal (detected at just 1 or 2 electrode contacts) typically registered at the nearest contact, regardless of type. IEDs that were regional (engaging more than 2 electrode contacts) typically appeared simultaneously at both electrode types. Neither method was better able to indicate whether an IED was mesial or lateral, posterior or anterior. Subdural and depth electrodes seem to provide complementary information on the location of IEDs within the temporal lobe.

Short Course on Implementation of Zone Technology in the Repair and Overhaul Environment

DTIC Science & Technology

1996-04-01

Pier Zone & Sys Pier/DD/Staging Zone Management Approach Varies Function to Project Project/Matrix Project/Matrix Project Project Fig. 9-3. Nature of...intractable problems that currently exist. Nature can give us many clues. If only we could harness the material that makes the dolphin’s outer shell so smooth...the natural effect of requiring peak manning and confined outfitting schedules. Through the application of system oriented logic to actual work accom

The Geometry of the Arms Race. Applications of Elementary Game Theory to International Relations. Modules and Monographs in Undergraduate Mathematics and Its Applications Project. UMAP Unit 311.

ERIC Educational Resources Information Center

Brams, Steven J.; And Others

This unit views applications of elementary game theory to international relations. It is noted that of all the significant world problems, the nuclear arms race has proved one of the most intractable. The main concern of the module is to investigate a possible solution to the arms race, based on extending the classic two-person game of Prisoner's…

Solving large-scale fixed cost integer linear programming models for grid-based location problems with heuristic techniques

NASA Astrophysics Data System (ADS)

Noor-E-Alam, Md.; Doucette, John

2015-08-01

Grid-based location problems (GBLPs) can be used to solve location problems in business, engineering, resource exploitation, and even in the field of medical sciences. To solve these decision problems, an integer linear programming (ILP) model is designed and developed to provide the optimal solution for GBLPs considering fixed cost criteria. Preliminary results show that the ILP model is efficient in solving small to moderate-sized problems. However, this ILP model becomes intractable in solving large-scale instances. Therefore, a decomposition heuristic is proposed to solve these large-scale GBLPs, which demonstrates significant reduction of solution runtimes. To benchmark the proposed heuristic, results are compared with the exact solution via ILP. The experimental results show that the proposed method significantly outperforms the exact method in runtime with minimal (and in most cases, no) loss of optimality.

Decision and function problems based on boson sampling

NASA Astrophysics Data System (ADS)

Nikolopoulos, Georgios M.; Brougham, Thomas

2016-07-01

Boson sampling is a mathematical problem that is strongly believed to be intractable for classical computers, whereas passive linear interferometers can produce samples efficiently. So far, the problem remains a computational curiosity, and the possible usefulness of boson-sampling devices is mainly limited to the proof of quantum supremacy. The purpose of this work is to investigate whether boson sampling can be used as a resource of decision and function problems that are computationally hard, and may thus have cryptographic applications. After the definition of a rather general theoretical framework for the design of such problems, we discuss their solution by means of a brute-force numerical approach, as well as by means of nonboson samplers. Moreover, we estimate the sample sizes required for their solution by passive linear interferometers, and it is shown that they are independent of the size of the Hilbert space.

Exploiting Quantum Resonance to Solve Combinatorial Problems

NASA Technical Reports Server (NTRS)

Zak, Michail; Fijany, Amir

2006-01-01

Quantum resonance would be exploited in a proposed quantum-computing approach to the solution of combinatorial optimization problems. In quantum computing in general, one takes advantage of the fact that an algorithm cannot be decoupled from the physical effects available to implement it. Prior approaches to quantum computing have involved exploitation of only a subset of known quantum physical effects, notably including parallelism and entanglement, but not including resonance. In the proposed approach, one would utilize the combinatorial properties of tensor-product decomposability of unitary evolution of many-particle quantum systems for physically simulating solutions to NP-complete problems (a class of problems that are intractable with respect to classical methods of computation). In this approach, reinforcement and selection of a desired solution would be executed by means of quantum resonance. Classes of NP-complete problems that are important in practice and could be solved by the proposed approach include planning, scheduling, search, and optimal design.

Oxidative stress, metalloproteinase and LDH in children with intractable and non-intractable epilepsy as reflected in salivary analysis.

PubMed

Shahar, Eli; Attias, Uri; Savulescu, Dana; Genizin, Jacob; Gavish, Moshe; Nagler, Rafael

2014-01-01

Oxidative stress and metalloproteinase (MMPs) may have a pivotal role in the pathogenesis of epilepsy. This study examined the underlying mechanism of epilepsy in children and especially in its intractable form, with respect to the roles of MMP's and free radicals in general and in saliva in particular. We also explored the possible diagnostic role of a compositional salivary analysis in these children, as salivary collection is simple, non-invasive (and thus 'children-friendly') and requires almost no expertise. We analyzed saliva parameters of 33 epileptic children: 22 with non-intractable (E's) and 11 with intractable epilepsy (IE's), and compared them with 16 healthy controls. Mean salivary LDH concentration in controls was 213.1±34.0IU/L, dropping by 38% (p=0.014) in E's and by 76% (p=0.0003) in IE's. Mean salivary values of peroxidase activity, SOD activity and carbonyls level were 480±14mU/mL, 1.30±0.15U/mL and 0.34±0.04nmol/mg, respectively, in controls, increasing by 6% (p=0.03), by 37% (p=0.04) and by 59% (p=0.003) in E's, and by 10% (p=0.02), by 29% (p=0.03) and by 56% (p=0.004) in IE's. Mean salivary MMP 9 concentration was 0.062±0.003 (OD) in controls, decreased by 12% (p=0.048) in E's, and by 23%, (p=0.009) in IE's. Our results enhance our understanding of epilepsy's biological underlying mechanism as reflected in the saliva of children with both intractable and non intractable disease. The currently reported salivary analysis and the demonstrated salivary alterations in children suffering from epilepsy represent a novel direction. We found various salivary alterations demonstrated in the general composition as well as the oxidative and metalloproteinase analyses and more so in the intractable epilepsy group than in the non intractable epilepsy group. Hence, salivary oxidative components and MMP levels were found useful in the detection and follow-up of children with epilepsy. As such, we recommend using this non-invasive salivary analysis for diagnosis and monitoring of epileptic activity in children. Copyright © 2013 Elsevier B.V. All rights reserved.

From CBA to Precautionary Appraisal: Practical Responses to Intractable Problems.

PubMed

Stirling, Andrew; Coburn, Josie

2018-01-01

The purpose of this essay is to critically review the design of methods for ethically robust forms of technology appraisal in the regulation of research and innovation in synthetic biology. It will focus, in particular, on the extent to which cost-benefit analysis offers a basis for informing decisions about which technological pathways to pursue and which to discourage. A further goal is to consider what (if anything) the precautionary principle might offer in enabling better decisions. And this, in turn, raises questions about why mention of precaution can excite accusations of unscientific bias or irrational, "anti-innovation" extremism. What does the polarized debate tell us about the politics around synthetic biology? In seeking more rigorous, timely, and practical ways to govern these remarkable new technologies, what might we be missing? The sophistication, diversity, and scope of synthetic biology may seem to make it a rather idiosyncratic area for exploring these general issues. It may seem to be a special case, with the bewildering pace of change amplifying the difficulties. But at root, some of the trickiest issues are just specific instances of familiar and long-standing conundrums in the governance of science and technology. The basic challenge is how to weigh up, for a wide range of potential options, the various pros and cons, as viewed from divergent perspectives, and find a way to justify the best course of action on behalf of society as a whole. This is the central problem addressed by a number of techniques in CBA. On the face of it, synthetic biology seems to present just one more application of these well-established and self-confident prescriptive methods. But there do emerge several obstinate, even prohibitive, difficulties for CBA. Although they are well acknowledged by the scholarly literature on and around this topic, they are often sidelined in practice. Yet all are central to the case for applying the concept of precaution to a field like synthetic biology. This essay will briefly explore multicriteria mapping, an appraisal method for exploring contrasting perspectives on emerging technologies, as one practical way to address them. The essay focuses on MCM, not because it presents any sort of panacea for appraisal, but because it is illustrative of the concrete implications of precaution. Setting out even just one among potentially many practical alternative methods at least refutes the last-ditch argument that CBA is the only operational choice. © 2018 The Hastings Center.

Empowerment: A fundamental tenet of risk communication and the Nimby syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stevens, A.D.

1995-12-01

Why do people want to be involved in decisions that have the potential to affect their community? Why not-wouldn`t you? The answer seems to obvious that it makes the question appear naive and trite. Yet, for years, government agencies and corporations have behaved in a manner that assumed the correctness of decisions and forced local residents to prove a right to be heard and to fight for the courtesy of respect. To the surprise and growing irritation of organization officials, the degree of trust and acceptance residents have for organizational pronouncements and activities has eroded into a seemingly intractable impediment.more » Given this environment, it is significant that two veins of social science research, risk communication and rhetorical theroy analyzing the Not-In-My-Back Yard (NIMBY) Phenomenon, are converging to the same point. Both approaches are finding that citizen empowerment--the legitimate intellectual sovereignty and meaningful involvement of individuals in decision making processes--is essential to the success of either type of communicative interaction. An appropriate context must precede the content in risk dialogue.« less

Partial pleural covering for intractable pneumothorax in patients with Birt-Hogg-Dubé Syndrome.

PubMed

Okada, Akira; Hirono, Tatsuhiko; Watanabe, Takehiro; Hasegawa, Go; Tanaka, Reiko; Furuya, Mitsuko

2017-03-01

Birt-Hogg-Dubé syndrome (BHD) is an inherited disorder associated with a germline mutation of the folliculin (FLCN) gene. Most patients with BHD have multiple pulmonary cysts, and are at high risk of repeated pneumothorax. Although an increasing number of patients are diagnosed with BHD by genetic testing, therapeutic approaches for intractable pneumothorax have not yet been described. We treated three patients who had repeated episodes of pneumothorax. All had multiple pulmonary cysts in the lower lobes, and two had a family history of pneumothorax. Video-assisted thoracic surgery was used to perform wedge resections and partial pleural covering of the cystic lesions. The partial pleural covering technique used sheets of polyglycolic acid felt or regenerative oxidized cellulose mesh. The resected tissues underwent histopathological evaluation, and peripheral blood leukocytes were tested for FLCN mutations. The operative times were less than 2 h, and there were no complications. The resected cysts had histopathological features characteristic of BHD lung. All patients were found to have FLCN germline mutations; thus their repeated pneumothoraces were a manifestation of BHD. None of the patients developed respiratory problems after undergoing the partial pleural covering procedure, and they have all been well without pneumothorax for 30 months or more. Partial pleural covering combined with resection of protruding cysts should be a safe and effective therapeutic approach for BHD patients with intractable pneumothorax. Further investigation is needed to establish a detailed protocol for treatment of pneumothorax that results in minimal functional impairment. © 2015 John Wiley & Sons Ltd.

Ultrasound-Guided Phrenic Nerve Block for Intractable Hiccups following Placement of Esophageal Stent for Esophageal Squamous Cell Carcinoma.

PubMed

Arsanious, David; Khoury, Spiro; Martinez, Edgar; Nawras, Ali; Filatoff, Gregory; Ajabnoor, Hossam; Darr, Umar; Atallah, Joseph

2016-05-01

Hiccups are actions consisting of sudden contractions of the diaphragm and intercostals followed by a sudden inspiration and transient closure of the vocal cords. They are generally short lived and benign; however, in extreme and rare cases, such as esophageal carcinoma, they can become persistent or intractable, up to and involving significant pain, dramatically impacting the patient's quality of life. This case involves a 60-year-old man with a known history of squamous cell carcinoma of the esophagus. He was considered to have high surgical risk, and therefore he received palliative care through the use of fully covered metallic esophageal self-expandable stents due to a spontaneous perforated esophagus, after which he developed intractable hiccups and associated mediastinal pain. Conservative treatment, including baclofen, chlorpromazine, metoclopramide, and omeprazole, provided no relief for his symptoms. The patient was referred to pain management from gastroenterology for consultation on pain control. He ultimately received an ultrasound-guided left phrenic nerve block with bupivacaine and depomedrol, and 3 days later underwent the identical procedure on the right phrenic nerve. This led to complete resolution of his hiccups and associated mediastinal pain. At follow-up, 2 and 4 weeks after the left phrenic nerve block, the patient was found to maintain complete alleviation of the hiccups. Esophageal dilatation and/or phrenic or vagal afferent fiber irritation can be suspected in cases of intractable hiccups secondary to esophageal stenting. Regional anesthesia of the phrenic nerve through ultrasound guidance offers a long-term therapeutic option for intractable hiccups and associated mediastinal pain in selected patients with esophageal carcinoma after stent placement. Esophageal stent, esophageal stenting, intractable hiccups, intractable singultus, phrenic nerve block, phrenic nerve, ultrasound, palliative care, esophageal carcinoma.

Up-regulated ephrinB3/EphB3 expression in intractable temporal lobe epilepsy patients and pilocarpine induced experimental epilepsy rat model.

PubMed

Huang, Hao; Li, Ruohan; Yuan, Jinxian; Zhou, Xin; Liu, Xi; Ou, Shu; Xu, Tao; Chen, Yangmei

2016-05-15

EphB family receptor tyrosine kinases, in cooperation with cell surface-bound ephrinB ligands, play a critical role in maintenance of dendritic spine morphogenesis, axons guidance, synaptogenesis, synaptic reorganization and plasticity in the central nervous system (CNS). However, the expression pattern of ephrinB/EphB in intractable temporal lobe epilepsy (TLE) and the underlying molecular mechanisms during epileptogenesis remain poorly understood. Here we investigated the expression pattern and cellular distribution of ephrinB/EphB in intractable TLE patients and lithium chloride-pilocarpine induced TLE rats using real-time quantitative polymerase chain reaction (RT-qPCR), immunohistochemistry, double-labeled immunofluorescence and Western blot analysis. Compared to control groups, ephrinB3 and EphB3 mRNA expression were significantly up-regulated in intractable TLE patients and TLE rats, while the mRNA expression trend of ephrinB1/2 and EphB1/2/4/6 in intractable TLE patients and TLE rats were inconsistent. Western blot analysis and semi-quantitative immunohistochemistry confirmed that ephrinB3 and EphB3 protein level were up-regulated in intractable TLE patients and TLE rats. At the same time, double-labeled immunofluorescence indicate that ephrinB3 was expressed mainly in the cytoplasm and protrusions of glia and neurons, while EphB3 was expressed mainly in the cytoplasm of neurons. Taken together, up-regulated expression of ephrinB3/EphB3 in intractable TLE patients and experimental TLE rats suggested that ephrinB3/EphB3 might be involved in the pathogenesis of TLE. Copyright © 2016 Elsevier B.V. All rights reserved.

Rethinking intractable conflict: the perspective of dynamical systems.

PubMed

Vallacher, Robin R; Coleman, Peter T; Nowak, Andrzej; Bui-Wrzosinska, Lan

2010-01-01

Intractable conflicts are demoralizing. Beyond destabilizing the families, communities, or international regions in which they occur, they tend to perpetuate the very conditions of misery and hate that contributed to them in the first place. Although the common factors and processes associated with intractable conflicts have been identified through research, they represent an embarrassment of riches for theory construction. Thus, the current task in this area is integrating these diverse factors into an account that provides a coherent perspective yet allows for prediction and a basis for conflict resolution in specific conflict settings. We suggest that the perspective of dynamical systems provides such an account. This article outlines the key concepts and hypotheses associated with this approach. It is organized around a set of basic questions concerning intractable conflict for which the dynamical perspective offers fresh insight and testable propositions. The questions and answers are intended to provide readers with basic concepts and principles of complexity and dynamical systems that are useful for rethinking the nature of intractable conflict and the means by which such conflict can be transformed. Copyright 2010 APA, all rights reserved.

Between universalism and relativism: a conceptual exploration of problems in formulating and applying international biomedical ethical guidelines

PubMed Central

Tangwa, G

2004-01-01

In this paper, the author attempts to explore some of the problems connected with the formulation and application of international biomedical ethical guidelines, with particular reference to Africa. Recent attempts at revising and updating some international medical ethical guidelines have been bedevilled by intractable controversies and wrangling regarding both the content and formulation. From the vantage position of relative familiarity with both African and Western contexts, and the privilege of having been involved in the revision and updating of one of the international ethical guidelines, the author reflects broadly on these issues and attempts prescribing an approach from both the theoretical and practical angles liable to mitigate, if not completely eliminate, some of the problems and difficulties. PMID:14872078

Multiple Causality: Consequences for Medical Practice

PubMed Central

Nydegger, Corinne N.

1983-01-01

When a scientifically trained health professional is called upon to deal with patients holding differing causal views of illness, the resulting lack of communication is frustrating to both. This discussion traces some implications for medical practice of significant cultural differences in two aspects of causal paradigms of illness: (1) terms accepted and (2) dimension or level of causality typically sought. The second is the more pervasive and intractable problem, having distinctive consequences for the role of curer, symptomatology, diagnosis and treatment. PMID:6858133

User interface concerns

NASA Technical Reports Server (NTRS)

Redhed, D. D.

1978-01-01

Three possible goals for the Numerical Aerodynamic Simulation Facility (NASF) are: (1) a computational fluid dynamics (as opposed to aerodynamics) algorithm development tool; (2) a specialized research laboratory facility for nearly intractable aerodynamics problems that industry encounters; and (3) a facility for industry to use in its normal aerodynamics design work that requires high computing rates. The central system issue for industry use of such a computer is the quality of the user interface as implemented in some kind of a front end to the vector processor.

Prospective study of POLG mutations presenting in children with intractable epilepsy: prevalence and clinical features.

PubMed

Uusimaa, Johanna; Gowda, Vasantha; McShane, Anthony; Smith, Conrad; Evans, Julie; Shrier, Annie; Narasimhan, Manisha; O'Rourke, Anthony; Rajabally, Yusuf; Hedderly, Tammy; Cowan, Frances; Fratter, Carl; Poulton, Joanna

2013-06-01

To assess the frequency and clinical features of childhood-onset intractable epilepsy caused by the most common mutations in the POLG gene, which encodes the catalytic subunit of mitochondrial DNA polymerase gamma. Children presenting with nonsyndromic intractable epilepsy of unknown etiology but without documented liver dysfunction at presentation were eligible for this prospective, population-based study. Blood samples were analyzed for the three most common POLG mutations. If any of the three tested mutations were found, all the exons and the exon-intron boundaries of the POLG gene were sequenced. In addition, we retrospectively reviewed the notes of patients presenting with intractable epilepsy in which we had found POLG mutations. All available clinical data were collected by questionnaire and by reviewing the medical records. We analyzed 213 blood DNA samples from patients fulfilling the inclusion criteria of the prospective study. Among these, five patients (2.3%) were found with one of the three common POLG mutations as homozygous or compound heterozygous states. In addition, three patients were retrospectively identified. Seven of the eight patients had either raised cerebrospinal fluid (CSF) lactate (n = 3) or brain magnetic resonance imaging (MRI) changes (n = 4) at presentation with intractable epilepsy. Three patients later developed liver dysfunction, progressing to fatal liver failure in two without previous treatment with sodium valproate (VPA). Furthermore, it is worth mentioning that one patient presented first with an autism spectrum disorder before seizures emerged. Mutations in POLG are an important cause of early and juvenile onset nonsyndromic intractable epilepsy with highly variable associated manifestations including autistic features. This study emphasizes that genetic testing for POLG mutations in patients with nonsyndromic intractable epilepsies is very important for clinical diagnostics, genetic counseling, and treatment decisions because of the increased risk for VPA-induced liver failure in patients with POLG mutations. We recommend POLG gene testing for patients with intractable seizures and at least one elevated CSF lactate or suggestive brain MRI changes (predominantly abnormal T2 -weighted thalamic signal) with or without status epilepticus, epilepsia partialis continua, or liver manifestations typical for Alpers disease, especially when the disease course is progressive. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

Prospective study of POLG mutations presenting in children with intractable epilepsy: Prevalence and clinical features

PubMed Central

Uusimaa, Johanna; Gowda, Vasantha; McShane, Anthony; Smith, Conrad; Evans, Julie; Shrier, Annie; Narasimhan, Manisha; O'Rourke, Anthony; Rajabally, Yusuf; Hedderly, Tammy; Cowan, Frances; Fratter, Carl; Poulton, Joanna

2013-01-01

Purpose To assess the frequency and clinical features of childhood-onset intractable epilepsy caused by the most common mutations in the POLG gene, which encodes the catalytic subunit of mitochondrial DNA polymerase gamma. Methods Children presenting with nonsyndromic intractable epilepsy of unknown etiology but without documented liver dysfunction at presentation were eligible for this prospective, population-based study. Blood samples were analyzed for the three most common POLG mutations. If any of the three tested mutations were found, all the exons and the exon–intron boundaries of the POLG gene were sequenced. In addition, we retrospectively reviewed the notes of patients presenting with intractable epilepsy in which we had found POLG mutations. All available clinical data were collected by questionnaire and by reviewing the medical records. Key Findings We analyzed 213 blood DNA samples from patients fulfilling the inclusion criteria of the prospective study. Among these, five patients (2.3%) were found with one of the three common POLG mutations as homozygous or compound heterozygous states. In addition, three patients were retrospectively identified. Seven of the eight patients had either raised cerebrospinal fluid (CSF) lactate (n = 3) or brain magnetic resonance imaging (MRI) changes (n = 4) at presentation with intractable epilepsy. Three patients later developed liver dysfunction, progressing to fatal liver failure in two without previous treatment with sodium valproate (VPA). Furthermore, it is worth mentioning that one patient presented first with an autism spectrum disorder before seizures emerged. Significance Mutations in POLG are an important cause of early and juvenile onset nonsyndromic intractable epilepsy with highly variable associated manifestations including autistic features. This study emphasizes that genetic testing for POLG mutations in patients with nonsyndromic intractable epilepsies is very important for clinical diagnostics, genetic counseling, and treatment decisions because of the increased risk for VPA-induced liver failure in patients with POLG mutations. We recommend POLG gene testing for patients with intractable seizures and at least one elevated CSF lactate or suggestive brain MRI changes (predominantly abnormal T2-weighted thalamic signal) with or without status epilepticus, epilepsia partialis continua, or liver manifestations typical for Alpers disease, especially when the disease course is progressive. PMID:23448099

Sequencing intractable DNA to close microbial genomes.

PubMed

Hurt, Richard A; Brown, Steven D; Podar, Mircea; Palumbo, Anthony V; Elias, Dwayne A

2012-01-01

Advancement in high throughput DNA sequencing technologies has supported a rapid proliferation of microbial genome sequencing projects, providing the genetic blueprint for in-depth studies. Oftentimes, difficult to sequence regions in microbial genomes are ruled "intractable" resulting in a growing number of genomes with sequence gaps deposited in databases. A procedure was developed to sequence such problematic regions in the "non-contiguous finished" Desulfovibrio desulfuricans ND132 genome (6 intractable gaps) and the Desulfovibrio africanus genome (1 intractable gap). The polynucleotides surrounding each gap formed GC rich secondary structures making the regions refractory to amplification and sequencing. Strand-displacing DNA polymerases used in concert with a novel ramped PCR extension cycle supported amplification and closure of all gap regions in both genomes. The developed procedures support accurate gene annotation, and provide a step-wise method that reduces the effort required for genome finishing.

Space-time acupuncture for intractable cough after lupus nephropathy: A case report and literature review.

PubMed

Guo, Taipin; Chen, Zukun; Tai, Xiantao; Liu, Zili; Zhu, Miansheng

2017-12-01

Some intractable chronic cough remains a common complaint for seeking medical care. Unexplained cough in lupus nephropathy patient is rare and therapeutic options are limited. A 57 year-old woman with a 7-year history of lupus nephropathy. She has suffered from chronic cough for 3 years accompanied with chronic low back pain and fatigue, as the conventional therapy cannot relieve the symptoms. The woman is diagnosed as intractable cough after lupus nephropathy. 9 times space-time acupuncture (STA) treatment was performed. The cough, as well as other uncomfortable symptoms like chronic low-back pain and fatigue have resolved, and no relapse for one year follow-up. STA may be an effective therapy to treat intractable chronic cough. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Is Bjerkandera adusta Important to fungus-associated chronic cough as an allergen? Eight cases' reports.

PubMed

Ogawa, Haruhiko; Fujimura, Masaki; Takeuchi, Yasuo; Makimura, Koichi

2009-10-01

Recently, we have reported a new clinical disease concept called fungus-associated chronic cough (FACC), which entailed the following manifestations: (1) chronic cough; (2) the presence of environmental fungi, particularly basidiomycetous (BM) fungi, in the sputum; and (3) good clinical response to antifungal drugs. To clarify the relationship between the exposure to environmental fungi and the development of cough attacks, we reviewed the clinical records of patients with FACC and performed a molecular biological analysis of the BM fungi. We successfully selected 8 patients with chronic cough, wherein a sputum culture yielded B. adusta beforehand; moreover, we conducted allergological tests such as the immediate-type skin test, a serological test, bronchoprovocation test, and lymphocyte stimulation test (LST), using the antigenic solution of B. adusta. The efficacy of individualized therapy and the clinical manifestations in the eight patients were examined. All the eight patients were diagnosed with FACC. Although three patients who did not show a positive reaction to the bronchoprovocation test or LST showed excellent clinical response to anti-fungal drugs; other 5 patients who showed a positive reaction to the bronchoprovocation test and/or LST seemed to be more intractable because of taking a longer time for complete remission and more frequent recurrence of cough. It was suggested that so-called allergic fungal cough (AFC), which is characterized by sensitization to B. adusta, may be included in a part of chronic intractable cough.

Persistent high TRAb values during pregnancy predict increased risk of neonatal hyperthyroidism following radioiodine therapy for refractory hyperthyroidism.

PubMed

Hamada, Noboru; Momotani, Naoko; Ishikawa, Naofumi; Yoshimura Noh, Jaeduk; Okamoto, Yasuyuki; Konishi, Toshiaki; Ito, Koichi; Ito, Kunihiko

2011-01-01

Serum levels of TSH receptor antibody (TRAb) often increase after radioiodine treatment for Graves' disease, and high-serum levels of maternal TRAb in late pregnancy indicate a risk of neonatal hyperthyroidism. The aim of this retrospective study is to investigate the characteristics of Graves' women who had a history of radioiodine treatment for intractable Graves' disease, and whose neonates suffered from hyperthyroidism. The subjects of this study were 45 patients with Graves' disease who became pregnant during the period from 1988 to 1998 after receiving radioiodine treatment at Ito Hospital. 25 of the 45 subjects had had a relapse of hyperthyroidism after surgical treatment for Graves' disease. 19 pregnancies were excluded because of artificial or spontaneous abortion. In the remaining 44 pregnancies of 35 patients, neonatal hyperthyroidism developed in 5 (11.3%) pregnancies of 4 patients. Serum levels of TRAb at delivery were higher in patients whose neonates suffered from hyperthyroidism (NH mother) than those of patients who delivered normal infants (N mother). Furthermore, serum levels of TRAb in NH mother did not change during pregnancy, although those of 4 patients of N mother, in which serum levels of TRAb before radioiodine treatment were as high as in NH mother, decreased significantly during pregnancy. In conclusion, women who delivered neonates with hyperthyroidism following radioiodine treatment seem to have very severe and intractable Graves' disease. Persistent high TRAb values during pregnancy observed in those patients may be a cause of neonatal hyperthyroidism.

Seizure control following radiotherapy in patients with diffuse gliomas: a retrospective study

PubMed Central

Rudà, Roberta; Magliola, Umberto; Bertero, Luca; Trevisan, Elisa; Bosa, Chiara; Mantovani, Cristina; Ricardi, Umberto; Castiglione, Anna; Monagheddu, Chiara; Soffietti, Riccardo

2013-01-01

Background Little information is available regarding the effect of conventional radiotherapy on glioma-related seizures. Methods In this retrospective study, we analyzed the seizure response and outcome following conventional radiotherapy in a cohort of 43 patients with glioma (33 grade II, 10 grade III) and medically intractable epilepsy. Results At 3 months after radiotherapy, seizure reduction was significant (≥50% reduction of frequency compared with baseline) in 31/43 patients (72%) of the whole series and in 25/33 patients (76%) with grade II gliomas, whereas at 12 months seizure reduction was significant in 26/34 (76%) and in 19/25 (76%) patients, respectively. Seizure reduction was observed more often among patients displaying an objective tumor response on MRI, but patients with no change on MRI also had a significant seizure reduction. Seizure freedom (Engel class I) was achieved at 12 months in 32% of all patients and in 38% of patients with grade II tumors. Timing of radiotherapy and duration of seizures prior to radiotherapy were significantly associated with seizure reduction. Conclusions This study showed that a high proportion of patients with medically intractable epilepsy from diffuse gliomas derive a significant and durable benefit from radiotherapy in terms of epilepsy control and that this positive effect is not strictly associated with tumor shrinkage as shown on MRI. Radiotherapy at tumor progression seems as effective as early radiotherapy after surgery. Prospective studies must confirm and better characterize the response to radiotherapy. PMID:23897633

A knowledge creation info-structure to acquire and crystallize the tacit knowledge of health-care experts.

PubMed

Abidi, Syed Sibte Raza; Cheah, Yu-N; Curran, Janet

2005-06-01

Tacit knowledge of health-care experts is an important source of experiential know-how, yet due to various operational and technical reasons, such health-care knowledge is not entirely harnessed and put into professional practice. Emerging knowledge-management (KM) solutions suggest strategies to acquire the seemingly intractable and nonarticulated tacit knowledge of health-care experts. This paper presents a KM methodology, together with its computational implementation, to 1) acquire the tacit knowledge possessed by health-care experts; 2) represent the acquired tacit health-care knowledge in a computational formalism--i.e., clinical scenarios--that allows the reuse of stored knowledge to acquire tacit knowledge; and 3) crystallize the acquired tacit knowledge so that it is validated for health-care decision-support and medical education systems.

Surgical Considerations of Intractable Mesial Temporal Lobe Epilepsy

PubMed Central

Boling, Warren W.

2018-01-01

Surgery of temporal lobe epilepsy is the best opportunity for seizure freedom in medically intractable patients. The surgical approach has evolved to recognize the paramount importance of the mesial temporal structures in the majority of patients with temporal lobe epilepsy who have a seizure origin in the mesial temporal structures. For those individuals with medically intractable mesial temporal lobe epilepsy, a selective amygdalohippocampectomy surgery can be done that provides an excellent opportunity for seizure freedom and limits the resection to temporal lobe structures primarily involved in seizure genesis. PMID:29461485

We Are All Engineers Now: Delivering Useful Projections Of Sea Level Rise

NASA Astrophysics Data System (ADS)

Pfeffer, W. T.

2011-12-01

Sea level rise is among the most tangible and potentially costly global changes facing society in the near future. Much of the uncertainty in future sea level rise lies in the determination of glacier and ice sheet contributions through melting of ice and through the discharge of icebergs directly into the ocean. As a consequence, many aspects of modern glaciological research have come to be motivated wholly or in part by the need to solve societally relevant problems involving future changes in sea level. To this extent, glaciology has become - temporarily - an applied science, in which the motivating questions are not purely scientific but practical in nature, and entail goals, deadlines and constraints that may or may not mesh comfortably with the skills, resources, and interests of the glaciological research community. This shift in motivation has subtle but important effects on how the glaciological community conducts research: we are no longer fully at liberty to explore only those problems that we judge to be the most intellectually stimulating and novel, or even the most likely to produce immediate results. We are obliged, at least if we are going to claim to be serving a critical societal need, to take on the entire spectrum of problems pertinent to sea level rise: the exciting with the mundane, the low-hanging fruit with the high-hanging, the tractable with the intractable. And in those intractable cases, and in other situations where the path to a solution is unclear, we must explore alternatives to our conventional approaches, and seek the means, if not to actually obtain solutions, to at least constrain the outcome and reduce the uncertainty of future knowledge. This broadening of methods is very much an engineer's approach to problem solving, but it also fits the philosopher/physicist P.W. Bridgman's definition of the scientific method as "Doing your damnedest, no holds barred."

Ketogenic diet for treatment of intractable epilepsy in adults: A meta-analysis of observational studies.

PubMed

Liu, Hongyan; Yang, Yi; Wang, Yunbing; Tang, Hong; Zhang, Fan; Zhang, Yong; Zhao, Yong

2018-03-01

The ketogenic diet (KD) is an effective treatment for children with drug-resistant epilepsy and has been widely used in young children. Adult patients with intractable epilepsy would also benefit from this dietary treatment. However, only a few studies have been published, and the use of the KD in intractable epilepsy in adults has been limited. This meta-analysis summarized the findings of the relevant published studies to identify the efficacy of the KD for the treatment of intractable epilepsy in adults. In this meta-analysis, PubMed, Embase, and Cochrane Library were used for searching studies concerning the effects of the KD and its major subtypes with intractable epilepsy in adults published up to January 10, 2017. The primary outcomes were seizure freedom, seizure reduction by 50% or more, and seizure reduction by <50%. The quality of the methodology of the observational studies was reviewed by using the Newcastle-Ottawa Scale. We identified 402 articles, of which, 16 studies including 338 patients met the inclusion criteria. The results of the meta-analysis showed that the combined efficacy rates of all the symptoms of seizure freedom, seizure reduction by 50% or more, and seizure reduction below 50% in adults with intractable epilepsy were 13%, 53%, and 27%, respectively. The adverse reactions of the KD were mild, whereas low glycemic index diet (LGID) and low-dose fish oil diet (LFOD) may have fewer side effects. Weight loss, high level of low-density lipoprotein, and elevated total cholesterol were most frequent. The meta-analysis indicates that the KD for refractory epilepsy in adults is a well-tolerated treatment and that its side effects are acceptable, which show that the KD is a promising treatment in adult intractable epilepsy. Further research is needed to assess which type of diet or ratio is more effective in the KD treatment.

Clinical presentation of asbestosis with intractable pleural pain in the adult child of a taconite miner and radiographic demonstration of the probable pathology causing the pain.

PubMed

Harbut, Michael R; Endress, Carmen; Graff, John J; Weis, Christopher; Pass, Harvey

2009-01-01

Taconite, although not classified by the United States Government as asbestos or asbestiform material, has been associated with asbestos-related diseases. The mineral is used in the production of steel and as a road-patch material and is mined in Michigan and Minnesota. This report describes the case of a middle-aged Caucasian woman with exposure to taconite mining dust from her miner father's clothing in childhood with a resultant presentation consistent with asbestosis and intractable pleural pain. Intractable pleural pain has been described in asbestos-exposed patients with theorized etiologies. However, no in vivo reported mechanism has demonstrated a plausible, anatomically apparent mechanism for the pain. We utilize an application of the Vitrea software for enhancement of high-resolution computerized tomography which demonstrates at least one likely mechanism for intractable pleural pain.

De novo mutations of KIAA2022 in females cause intellectual disability and intractable epilepsy.

PubMed

de Lange, Iris M; Helbig, Katherine L; Weckhuysen, Sarah; Møller, Rikke S; Velinov, Milen; Dolzhanskaya, Natalia; Marsh, Eric; Helbig, Ingo; Devinsky, Orrin; Tang, Sha; Mefford, Heather C; Myers, Candace T; van Paesschen, Wim; Striano, Pasquale; van Gassen, Koen; van Kempen, Marjan; de Kovel, Carolien G F; Piard, Juliette; Minassian, Berge A; Nezarati, Marjan M; Pessoa, André; Jacquette, Aurelia; Maher, Bridget; Balestrini, Simona; Sisodiya, Sanjay; Warde, Marie Therese Abi; De St Martin, Anne; Chelly, Jamel; van 't Slot, Ruben; Van Maldergem, Lionel; Brilstra, Eva H; Koeleman, Bobby P C

2016-12-01

Mutations in the KIAA2022 gene have been reported in male patients with X-linked intellectual disability, and related female carriers were unaffected. Here, we report 14 female patients who carry a heterozygous de novo KIAA2022 mutation and share a phenotype characterised by intellectual disability and epilepsy. Reported females were selected for genetic testing because of substantial developmental problems and/or epilepsy. X-inactivation and expression studies were performed when possible. All mutations were predicted to result in a frameshift or premature stop. 12 out of 14 patients had intractable epilepsy with myoclonic and/or absence seizures, and generalised in 11. Thirteen patients had mild to severe intellectual disability. This female phenotype partially overlaps with the reported male phenotype which consists of more severe intellectual disability, microcephaly, growth retardation, facial dysmorphisms and, less frequently, epilepsy. One female patient showed completely skewed X-inactivation, complete absence of RNA expression in blood and a phenotype similar to male patients. In the six other tested patients, X-inactivation was random, confirmed by a non-significant twofold to threefold decrease of RNA expression in blood, consistent with the expected mosaicism between cells expressing mutant or normal KIAA2022 alleles. Heterozygous loss of KIAA2022 expression is a cause of intellectual disability in females. Compared with its hemizygous male counterpart, the heterozygous female disease has less severe intellectual disability, but is more often associated with a severe and intractable myoclonic epilepsy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Optimal routing of IP packets to multi-homed servers

NASA Astrophysics Data System (ADS)

Swartz, K. L.

1992-08-01

Multi-homing, or direct attachment to multiple networks, offers both performance and availability benefits for important servers on busy networks. Exploiting these benefits to their fullest requires a modicum of routing knowledge in the clients. Careful policy control must also be reflected in the routing used within the network to make best use of specialized and often scarce resources. While relatively straightforward in theory, this problem becomes much more difficult to solve in a real network containing often intractable implementations from a variety of vendors. This paper presents an analysis of the problem and proposes a useful solution for a typical campus network. Application of this solution at the Stanford Linear Accelerator Center is studied and the problems and pitfalls encountered are discussed, as are the workarounds used to make the system work in the real world.

Solving the Swath Segment Selection Problem

NASA Technical Reports Server (NTRS)

Knight, Russell; Smith, Benjamin

2006-01-01

Several artificial-intelligence search techniques have been tested as means of solving the swath segment selection problem (SSSP) -- a real-world problem that is not only of interest in its own right, but is also useful as a test bed for search techniques in general. In simplest terms, the SSSP is the problem of scheduling the observation times of an airborne or spaceborne synthetic-aperture radar (SAR) system to effect the maximum coverage of a specified area (denoted the target), given a schedule of downlinks (opportunities for radio transmission of SAR scan data to a ground station), given the limit on the quantity of SAR scan data that can be stored in an onboard memory between downlink opportunities, and given the limit on the achievable downlink data rate. The SSSP is NP complete (short for "nondeterministic polynomial time complete" -- characteristic of a class of intractable problems that can be solved only by use of computers capable of making guesses and then checking the guesses in polynomial time).

Approximability of the d-dimensional Euclidean capacitated vehicle routing problem

NASA Astrophysics Data System (ADS)

Khachay, Michael; Dubinin, Roman

2016-10-01

Capacitated Vehicle Routing Problem (CVRP) is the well known intractable combinatorial optimization problem, which remains NP-hard even in the Euclidean plane. Since the introduction of this problem in the middle of the 20th century, many researchers were involved into the study of its approximability. Most of the results obtained in this field are based on the well known Iterated Tour Partition heuristic proposed by M. Haimovich and A. Rinnoy Kan in their celebrated paper, where they construct the first Polynomial Time Approximation Scheme (PTAS) for the single depot CVRP in ℝ2. For decades, this result was extended by many authors to numerous useful modifications of the problem taking into account multiple depots, pick up and delivery options, time window restrictions, etc. But, to the best of our knowledge, almost none of these results go beyond the Euclidean plane. In this paper, we try to bridge this gap and propose a EPTAS for the Euclidean CVRP for any fixed dimension.

Use of an Oral Elemental Diet in Infants with Severe Intractable Diarrhea

ERIC Educational Resources Information Center

Sherman, Joseph O.; And Others

1975-01-01

Evaluated was the use of an oral elemental diet consisting of crystalline amino acids, glucose, electrolytes, and vitamins to control severe intractable diarrhea in 27 infants (1-day to 9-months of age). (DB)

Earth Science Data Analysis in the Era of Big Data

NASA Technical Reports Server (NTRS)

Kuo, K.-S.; Clune, T. L.; Ramachandran, R.

2014-01-01

Anyone with even a cursory interest in information technology cannot help but recognize that "Big Data" is one of the most fashionable catchphrases of late. From accurate voice and facial recognition, language translation, and airfare prediction and comparison, to monitoring the real-time spread of flu, Big Data techniques have been applied to many seemingly intractable problems with spectacular successes. They appear to be a rewarding way to approach many currently unsolved problems. Few fields of research can claim a longer history with problems involving voluminous data than Earth science. The problems we are facing today with our Earth's future are more complex and carry potentially graver consequences than the examples given above. How has our climate changed? Beside natural variations, what is causing these changes? What are the processes involved and through what mechanisms are these connected? How will they impact life as we know it? In attempts to answer these questions, we have resorted to observations and numerical simulations with ever-finer resolutions, which continue to feed the "data deluge." Plausibly, many Earth scientists are wondering: How will Big Data technologies benefit Earth science research? As an example from the global water cycle, one subdomain among many in Earth science, how would these technologies accelerate the analysis of decades of global precipitation to ascertain the changes in its characteristics, to validate these changes in predictive climate models, and to infer the implications of these changes to ecosystems, economies, and public health? Earth science researchers need a viable way to harness the power of Big Data technologies to analyze large volumes and varieties of data with velocity and veracity. Beyond providing speedy data analysis capabilities, Big Data technologies can also play a crucial, albeit indirect, role in boosting scientific productivity by facilitating effective collaboration within an analysis environment. To illustrate the effects of combining a Big Data technology with an effective means of collaboration, we relate the (fictitious) experience of an early-career Earth science researcher a few years beyond the present, interlaced and contrasted with reminiscences of its recent past (i.e., the present).

Firefly algorithm for cardinality constrained mean-variance portfolio optimization problem with entropy diversity constraint.

PubMed

Bacanin, Nebojsa; Tuba, Milan

2014-01-01

Portfolio optimization (selection) problem is an important and hard optimization problem that, with the addition of necessary realistic constraints, becomes computationally intractable. Nature-inspired metaheuristics are appropriate for solving such problems; however, literature review shows that there are very few applications of nature-inspired metaheuristics to portfolio optimization problem. This is especially true for swarm intelligence algorithms which represent the newer branch of nature-inspired algorithms. No application of any swarm intelligence metaheuristics to cardinality constrained mean-variance (CCMV) portfolio problem with entropy constraint was found in the literature. This paper introduces modified firefly algorithm (FA) for the CCMV portfolio model with entropy constraint. Firefly algorithm is one of the latest, very successful swarm intelligence algorithm; however, it exhibits some deficiencies when applied to constrained problems. To overcome lack of exploration power during early iterations, we modified the algorithm and tested it on standard portfolio benchmark data sets used in the literature. Our proposed modified firefly algorithm proved to be better than other state-of-the-art algorithms, while introduction of entropy diversity constraint further improved results.

Firefly Algorithm for Cardinality Constrained Mean-Variance Portfolio Optimization Problem with Entropy Diversity Constraint

PubMed Central

2014-01-01

Portfolio optimization (selection) problem is an important and hard optimization problem that, with the addition of necessary realistic constraints, becomes computationally intractable. Nature-inspired metaheuristics are appropriate for solving such problems; however, literature review shows that there are very few applications of nature-inspired metaheuristics to portfolio optimization problem. This is especially true for swarm intelligence algorithms which represent the newer branch of nature-inspired algorithms. No application of any swarm intelligence metaheuristics to cardinality constrained mean-variance (CCMV) portfolio problem with entropy constraint was found in the literature. This paper introduces modified firefly algorithm (FA) for the CCMV portfolio model with entropy constraint. Firefly algorithm is one of the latest, very successful swarm intelligence algorithm; however, it exhibits some deficiencies when applied to constrained problems. To overcome lack of exploration power during early iterations, we modified the algorithm and tested it on standard portfolio benchmark data sets used in the literature. Our proposed modified firefly algorithm proved to be better than other state-of-the-art algorithms, while introduction of entropy diversity constraint further improved results. PMID:24991645

Clinical studies of the Research Committee on Intractable Vasculitides, the Ministry of Health, Labour and Welfare of Japan.

PubMed

Makino, Hirofumi; Sada, Ken-Ei

2013-10-01

In Japan, the Research Committee on Intractable Vasculitides, supported by the Ministry of Health, Labour and Welfare, has been promoting basic and clinical research on vasculitis since 1972. The present Research Committee on Intractable Vasculitides comprises 4 subcommittees under the direction of a Principal Investigator: Basic and Pathological Research Subcommittee, Clinical Research Subcommittee of Small and Medium-sized Vessel Vasculitis, Clinical Research Subcommittee of Large-sized Vessel Vasculitis, and International Cooperation Research Subcommittee. Since 2008, 9 nationwide clinical studies for vasculitis have been conducted and 8 clinical and basic studies are in progress.

Secondary Voice Restoration After Laryngotracheal Separation (LTS) for Dysphagia with Intractable Aspiration.

PubMed

Bonte, Katrien; Huvenne, Wouter; De Loof, Marie; Deron, Philippe; Viaene, Annick; Duprez, Fréderic; Vermeersch, Hubert

2015-12-01

Intractable aspiration is a serious, often life-threatening condition due to its potential impact on pulmonary function. Aspiration requires therapeutic measures, starting with conservative management but often necessitating surgical treatment. The basic surgical principle is to separate the alimentary and respiratory tracts through a variety of procedures which, unfortunately, nearly all result in the loss of phonation, with the exception of total laryngectomy (TL) which includes the placement of an indwelling voice prosthesis. In this study, we present a modified laryngotracheal separation (LTS) technique that, we believe, offers multiple advantages compared to standard TL. After reviewing the medical records of 35 patients with intractable aspiration who have undergone LTS, we describe the surgical technique and present the postoperative result. In a second surgical procedure about two months following LTS, we aimed to achieve voice restoration by placement of an indwelling voice prosthesis. Intractable aspiration was successfully treated in all patients. Placement of an indwelling voice prosthesis during a second operation was successful in 15 patients, representing the largest reported cohort thus far. LTS is a reliable surgical technique to treat intractable aspiration, with restoration of oral intake, thereby improving the general condition and quality of life of these unfortunate patients. Furthermore, voice restoration can be achieved in selected patients, by placement of a voice prosthesis.

In situ accurate determination of the zero time delay between two independent ultrashort laser pulses by observing the oscillation of an atomic excited wave packet.

PubMed

Zhang, Qun; Hepburn, John W

2008-08-15

We propose a novel method that uses the oscillation of an atomic excited wave packet observed through a pump-probe technique to accurately determine the zero time delay between a pair of ultrashort laser pulses. This physically based approach provides an easy fix for the intractable problem of synchronizing two different femtosecond laser pulses in a practical experimental environment, especially where an in situ time zero measurement with high accuracy is required.

Decisive Routing and Admission Control According to Quality of Service Constraints

DTIC Science & Technology

2009-03-01

Level &(Key Size) 1 1 RSA (1280); RSA (1536); Elg-E (1280) 1 2 Elg-E ( 768 ); Elg-E(1024); RSA (1024) 1 3 3DES, BlowFish, CAST5 2 1 Elg-E(1536); Elg-E(1792...upon the intractibility of the discrete logarithm problem [11] RSA A public key encryption scheme named after inventors R. Rivest, A. Shamir, and L...gpgTester would make system calls to the GNU Privacy Guard to choose from system and public key algorithms, ElGamal, RSA , AES, AES192, AES256, TwoFish

Perverse dreams and dreams of perversion.

PubMed

Good, Michael I

2006-10-01

This paper (1) posits the occurrence of perverse dreams as a type of mental phenomenon in the constellation of perverse processes; (2) considers manifest dreams of frank perversion as a type of perverse dream within the class of perverse dreams as a whole; (3) relates the subtype of perverse dreams without manifest perversions to the occurrence of perverse defenses and the development of a perverse transference; and (4) suggests that consideration to perverse dreams in the psychoanalytic process finds application in identifying and differentiating perverse defenses from neurotic and other characterologic patterns; in identifying and tracing the vicissitudes of difficult perverse transference-countertransference constellations; and in furthering perverse patients' recognition and understanding of particularly troublesome and seemingly intractable issues in their psychic makeup. Clinical material illustrates perverse dreams and their usefulness in the often arduous process of analyzing perverse defenses.

Neuroscience and Ethics.

PubMed

Liao, S Matthew

2017-03-01

A number of people believe that results from neuroscience have the potential to settle seemingly intractable debates concerning the nature, practice, and reliability of moral judgments. In particular, Joshua Greene has argued that evidence from neuroscience can be used to advance the long-standing debate between consequentialism and deontology. This paper first argues that charitably interpreted, Greene's neuroscientific evidence can contribute to substantive ethical discussions by being part of an epistemic debunking argument. It then argues that taken as an epistemic debunking argument, Greene's argument falls short in undermining deontological judgments. Lastly, it proposes that accepting Greene's methodology at face value, neuroimaging results may in fact call into question the reliability of consequentialist judgments. The upshot is that Greene's empirical results do not undermine deontology and that Greene's project points toward a way by which empirical evidence such as neuroscientific evidence can play a role in normative debates.

[Preoperative evaluation of surgery for intractable aspiration based on the prognostic nutritional index].

PubMed

Uchida, Masaya; Hashimoto, Keiko; Mukudai, Shigeyuki; Ushijima, Chihisa; Dejima, Kenji

2014-12-01

Because there is no absolute indicator of the nutritional status and prognosis in patients with severe aspiration problems, it is quite difficult to arrive at a true long-time prognosis. By performing surgery for intractable aspiration on such patients, both the prognosis and QOL of the patients could be expected to improve. In our department, we have experienced patients dying within 6 months after surgery. In these cases, the patient's preoperative nutritional status was not good. Therefore, we consider that, when we adopt this procedure, there should be some indicators we should use which could have an effect on the prognosis of such nutritionally-challenged patients. In patients who underwent surgery for intractable aspiration; we examined the relationship between their survival and the prognostic nutritional index (PNI) which is an indicator of the risk of complications such as post-operative events in the surgical field. We investigated the relationship between the prognosis and the postoperative indicators of each of the following: WBC, CRP, serum albumin level, and PNI. Out of a total of 31 cases, the average O-PNI of eight cases in which death occurred was 29.45, and the average of six cases in which death occurred within 6 months after surgery was 28.26. The average O-PNI of the survivors was 36.01. A significant association was noted between the early postoperative deaths and some of the four indicators namely that serum albumin level and O-PNI. Based on the ROC curve, the O-PNI offered higher precision than the albumin level. The cut-off value of the O-PNI value for early postoperative mortality rate was 32. The early postoperative mortality rate was 44.4% in patients with less than 32 O-PNI in the preoperative examination, but if it were O-PNI 32 or more, the early postoperative mortality rate was 9.1%, significantly lower. Therefore, O-PNI could be useful as one of the prognostic evaluation factors in the case of preoperative surgery for intractable aspiration. Based on the O-PNI score, it was possible to evaluate the survival benefit associated with this operative procedure. We showed a treatment algorithm based on the preoperative O-PNI value. We believe there is a necessity to develop preoperative effective nutritional therapy as a future issue.

Short-term effect of ECT in middle-aged and elderly patients with intractable catatonic schizophrenia.

PubMed

Suzuki, Kazumasa; Awata, Shuichi; Matsuoka, Hiroo

2003-06-01

The management of middle-aged and elderly patients with catatonic schizophrenia has long been a major problem in clinical geriatric psychiatry. Most cases are intractable because of medication resistance, medication intolerance, or severe medical conditions. Electroconvulsive therapy (ECT) is recognized as one of the most efficacious therapies for catatonic schizophrenia. Thus, we conducted a prospective study of the short-term effect of acute ECT on middle-aged and elderly patients with intractable catatonic schizophrenia. Subjects were nine consecutive patients older than 45 years who had fulfilled the DSM-IV criteria for catatonic-type schizophrenia and had been referred for first-time acute ECT after other treatments had failed. The patients were treated at Tohoku University Hospital between January 1998 and March 2002. We evaluated the clinical response of these patients to acute ECT by means of the brief psychiatric rating scale (BPRS). We also evaluated adverse effects of acute ECT. The response rate was 100%. The total BPRS score was improved in all nine subjects at the end of the ECT course and 1 week after the final session in comparison with the total pre-ECT BPRS score (11.9 +/- 7.5 and 9.3 +/- 9.2 versus 57.1 +/- 13.1, respectively, p = 0.008, p = 0.008). The total Global Assessment of Functioning score was also improved significantly (from 10.8 +/- 9.4 just before ECT to 61.6 +/- 18.9 1 week after ECT, p = 0.008). Guy's five factors (thought disturbance, activation, anxiety-depression, hostility-suspiciousness, and anergia) improved significantly (p = 0.008, p = 0.008, p = 0.018, p = 0.012, p = 0.008, respectively). One patient showed supraventricular premature contractions (SVPCs) during an ECT seizure. After some ECT sessions, three patients exhibited mild to moderate delirium that disappeared within 3 days. However, no patient experienced a severe cognitive or physical adverse effect during the course of ECT. Acute ECT has a good short-term effect on middle-aged and elderly patients with intractable catatonic schizophrenia and appears to be safe. Our results indicate that systematic studies on a large scale are warranted for further investigation of the efficacy and safety of acute ECT for treating middle-aged and elderly patients with catatonic schizophrenia.

Replicating the benefits of Deutschian closed timelike curves without breaking causality

NASA Astrophysics Data System (ADS)

Yuan, Xiao; Assad, Syed M.; Thompson, Jayne; Haw, Jing Yan; Vedral, Vlatko; Ralph, Timothy C.; Lam, Ping Koy; Weedbrook, Christian; Gu, Mile

2015-11-01

In general relativity, closed timelike curves can break causality with remarkable and unsettling consequences. At the classical level, they induce causal paradoxes disturbing enough to motivate conjectures that explicitly prevent their existence. At the quantum level such problems can be resolved through the Deutschian formalism, however this induces radical benefits—from cloning unknown quantum states to solving problems intractable to quantum computers. Instinctively, one expects these benefits to vanish if causality is respected. Here we show that in harnessing entanglement, we can efficiently solve NP-complete problems and clone arbitrary quantum states—even when all time-travelling systems are completely isolated from the past. Thus, the many defining benefits of Deutschian closed timelike curves can still be harnessed, even when causality is preserved. Our results unveil a subtle interplay between entanglement and general relativity, and significantly improve the potential of probing the radical effects that may exist at the interface between relativity and quantum theory.

Machine learning applications in proteomics research: how the past can boost the future.

PubMed

Kelchtermans, Pieter; Bittremieux, Wout; De Grave, Kurt; Degroeve, Sven; Ramon, Jan; Laukens, Kris; Valkenborg, Dirk; Barsnes, Harald; Martens, Lennart

2014-03-01

Machine learning is a subdiscipline within artificial intelligence that focuses on algorithms that allow computers to learn solving a (complex) problem from existing data. This ability can be used to generate a solution to a particularly intractable problem, given that enough data are available to train and subsequently evaluate an algorithm on. Since MS-based proteomics has no shortage of complex problems, and since publicly available data are becoming available in ever growing amounts, machine learning is fast becoming a very popular tool in the field. We here therefore present an overview of the different applications of machine learning in proteomics that together cover nearly the entire wet- and dry-lab workflow, and that address key bottlenecks in experiment planning and design, as well as in data processing and analysis. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Coral reefs in the Gulf are mostly dead now, but can we do anything about it?

PubMed

Sheppard, Charles

2016-04-30

This article discusses two key issues: firstly, the demise of reefs in the Gulf which is happening probably more rapidly than elsewhere; and secondly, the reasons why this remains such an intractable problem. Most reasons for this decline are scientifically well understood, though clearly not by the region's managers. Several factors may cause people to ignore the problem, even though habitat loss is vastly costly to the region. About 70% of the Gulf's reefs have essentially disappeared in a few decades, and although scientific indicators confirm that this is happening, it is commonly discounted as even being a possibility. Management of human interactions with the Gulf's marine systems remains very inadequate, to the detriment of the Gulf's marine systems and its people. It is clear that this not a scientific issue any longer but rather it is a political problem and failure. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Center for Multiscale Plasma Dynamics, Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gombosi, Tamas I.

The University of Michigan participated in the joint UCLA/Maryland fusion science center focused on plasma physics problems for which the traditional separation of the dynamics into microscale and macroscale processes breaks down. These processes involve large scale flows and magnetic fields tightly coupled to the small scale, kinetic dynamics of turbulence, particle acceleration and energy cascade. The interaction between these vastly disparate scales controls the evolution of the system. The enormous range of temporal and spatial scales associated with these problems renders direct simulation intractable even in computations that use the largest existing parallel computers. Our efforts focused on twomore » main problems: the development of Hall MHD solvers on solution adaptive grids and the development of solution adaptive grids using generalized coordinates so that the proper geometry of inertial confinement can be taken into account and efficient refinement strategies can be obtained.« less

Effect of Direct Stimulation of the Cochleovestibular Nerve on Tinnitus: A Long-Term Follow-Up Study.

PubMed

van den Berge, Minke J C; van Dijk, J Marc C; Free, Rolien H; Stienstra, Janke; van Dijk, Pim; van der Laan, Bernard F A M

2017-02-01

Tinnitus is a common entity that may lead to severe impairment in quality of life. An adequate treatment modality for severe tinnitus is currently lacking. Neurostimulation of the auditory tract may serve as a promising adjunct in tinnitus treatment. The aim is to investigate the effect of direct stimulation on the cochleovestibular nerve for intractable tinnitus. This study was conducted at the University Medical Center Groningen, The Netherlands. We studied 10 patients with severe, unilateral, intractable tinnitus, who were implanted with a cuff electrode around the cochleovestibular nerve between 2001 and 2013. All patients had preoperative ipsilateral hearing loss. Tinnitus Handicap Inventory (THI) scores and audiometric values were collected. Treatment success was determined based on the self-assessment of satisfactory usage by each patient. The mean preoperative tinnitus duration was 8.0 ± 5.9 years. The preoperative THI score was 71 ± 18 points. During mean follow-up of 49 months, the mean THI reduction was 24 ± 26 points (P = 0.02). Treatment was regarded successful in 6 patients (60%). In these patients, tinnitus did not disappear, but transformed into a more bearable sound. In 4 patients, transient complications occurred, and 1 patient experienced permanent vertigo postoperatively. Furthermore, hearing deterioration was a result of implantation in 86% of the patients. Direct neurostimulation resulted in treatment success in a small majority of the patients, with a significant decrease in THI score. However, because of a high risk of additional hearing damage, this technique seems not viable for patients with moderate hearing loss. Copyright © 2016 Elsevier Inc. All rights reserved.

Ultrasound-guided placement of a permanent percutaneous femoral nerve stimulator leads for the treatment of intractable femoral neuropathy.

PubMed

Narouze, Samer N; Zakari, Adel; Vydyanathan, Amaresh

2009-01-01

Femoral nerve injury is a rare complication of cardiac catheterization and is usually caused by direct trauma during femoral artery access, compression from a hematoma, or prolonged digital pressure for post-procedural hemostasis. Peripheral nerve stimulation has been used to treat different pain syndromes in the upper and lower extremities with variable success and it typically requires direct vision with open surgical approach. Since the femoral nerve can be readily seen with ultrasonography, an ultrasound-guided lead placement seemed practical. A 61-year-old morbidly obese male who sustained femoral nerve injury during cardiac catheterization continued to complain of intractable femoral neuropathy 18 months afterwords. He failed multiple treatment modalities and continued to complain of severe neuropathic pains that markedly interfere with his daily activities. Two percutaneous leads were placed under real-time ultrasonography and the placement was confirmed with fluoroscopy. One lead was placed along the longitudinal axis of the nerve and the patient had good coverage over the anterior thigh but not below the knee. So another lead was placed horizontally across the femoral nerve in order to stimulate all the branches and the patient reported good coverage along the saphenous nerve distribution down to the foot. The patient continues to be pain free 20 months after the implant. Here we described a novel non-invasive percutaneous approach for femoral nerve stimulation with ultrasound guidance which allowed precise placement of the stimulating lead very close to the femoral nerve without the need for surgical exploration.

[Therapeutic effect of cervical Jiaji electroacupuncture on postoperative intractable hiccup of liver neoplasms].

PubMed

Zhang, S K; Gao, W B; Liu, Y; He, H

2018-02-23

Objective: To evaluate the therapeutic effect of cervical Jiaji electroacupuncture on postoperative intractable hiccup of liver neoplasms. Methods: A total of 39 patients with postoperative intractable hiccup of liver neoplasms in The First Affiliated Hospital of Heilongjiang University of Chinese Medicine from May 2013 to May 2017 were collected and divided into 2 groups randomly. The electroacupuncture group included 20 cases, the control group included 19 cases. Patients in the electroacupuncture group were treated by cervical Jiaji electroacupuncture (located in C3-5, sympathetic ganglion), while the control group were treated by metoclopramide combined with chlorpromazine for three days. The therapeutic effects of two groups were compared and the onset time were recorded. Results: Total effective rates of electroacupuncture group and control group were 95.0% and 47.4%, respectively. The onset time in electroacupuncture group and control group were (14.8±3.3) h and (30.5±3.1) h, respectively ( P <0.01). Ten cases who resisted the control treatment were then treated by electroacupuncture for 3 days, 6 cases were recovered, 3 cases became better, while 1 case demonstrated no response. No serious adverse reactions were appeared in each group. Conclusion: Cervical Jiaji electroacupuncture is an effective and safe treatment for postoperative intractable hiccup of liver neoplasms, and it can be used as a remedy for intractable hiccup patients who don't respond to drug treatment.

Towards a PTAS for the generalized TSP in grid clusters

NASA Astrophysics Data System (ADS)

Khachay, Michael; Neznakhina, Katherine

2016-10-01

The Generalized Traveling Salesman Problem (GTSP) is a combinatorial optimization problem, which is to find a minimum cost cycle visiting one point (city) from each cluster exactly. We consider a geometric case of this problem, where n nodes are given inside the integer grid (in the Euclidean plane), each grid cell is a unit square. Clusters are induced by cells `populated' by nodes of the given instance. Even in this special setting, the GTSP remains intractable enclosing the classic Euclidean TSP on the plane. Recently, it was shown that the problem has (1.5+8√2+ɛ)-approximation algorithm with complexity bound depending on n and k polynomially, where k is the number of clusters. In this paper, we propose two approximation algorithms for the Euclidean GTSP on grid clusters. For any fixed k, both algorithms are PTAS. Time complexity of the first one remains polynomial for k = O(log n) while the second one is a PTAS, when k = n - O(log n).

An Eigenvalue Analysis of finite-difference approximations for hyperbolic IBVPs

NASA Technical Reports Server (NTRS)

Warming, Robert F.; Beam, Richard M.

1989-01-01

The eigenvalue spectrum associated with a linear finite-difference approximation plays a crucial role in the stability analysis and in the actual computational performance of the discrete approximation. The eigenvalue spectrum associated with the Lax-Wendroff scheme applied to a model hyperbolic equation was investigated. For an initial-boundary-value problem (IBVP) on a finite domain, the eigenvalue or normal mode analysis is analytically intractable. A study of auxiliary problems (Dirichlet and quarter-plane) leads to asymptotic estimates of the eigenvalue spectrum and to an identification of individual modes as either benign or unstable. The asymptotic analysis establishes an intuitive as well as quantitative connection between the algebraic tests in the theory of Gustafsson, Kreiss, and Sundstrom and Lax-Richtmyer L(sub 2) stability on a finite domain.

Optimal mapping of irregular finite element domains to parallel processors

NASA Technical Reports Server (NTRS)

Flower, J.; Otto, S.; Salama, M.

1987-01-01

Mapping the solution domain of n-finite elements into N-subdomains that may be processed in parallel by N-processors is an optimal one if the subdomain decomposition results in a well-balanced workload distribution among the processors. The problem is discussed in the context of irregular finite element domains as an important aspect of the efficient utilization of the capabilities of emerging multiprocessor computers. Finding the optimal mapping is an intractable combinatorial optimization problem, for which a satisfactory approximate solution is obtained here by analogy to a method used in statistical mechanics for simulating the annealing process in solids. The simulated annealing analogy and algorithm are described, and numerical results are given for mapping an irregular two-dimensional finite element domain containing a singularity onto the Hypercube computer.

Temporal Lobe Epilepsy in Children

PubMed Central

Nickels, Katherine C.; Wong-Kisiel, Lily C.; Moseley, Brian D.; Wirrell, Elaine C.

2012-01-01

The temporal lobe is a common focus for epilepsy. Temporal lobe epilepsy in infants and children differs from the relatively homogeneous syndrome seen in adults in several important clinical and pathological ways. Seizure semiology varies by age, and the ictal EEG pattern may be less clear cut than what is seen in adults. Additionally, the occurrence of intractable seizures in the developing brain may impact neurocognitive function remote from the temporal area. While many children will respond favorably to medical therapy, those with focal imaging abnormalities including cortical dysplasia, hippocampal sclerosis, or low-grade tumors are likely to be intractable. Expedient workup and surgical intervention in these medically intractable cases are needed to maximize long-term developmental outcome. PMID:22957247

Parallel algorithms for mapping pipelined and parallel computations

NASA Technical Reports Server (NTRS)

Nicol, David M.

1988-01-01

Many computational problems in image processing, signal processing, and scientific computing are naturally structured for either pipelined or parallel computation. When mapping such problems onto a parallel architecture it is often necessary to aggregate an obvious problem decomposition. Even in this context the general mapping problem is known to be computationally intractable, but recent advances have been made in identifying classes of problems and architectures for which optimal solutions can be found in polynomial time. Among these, the mapping of pipelined or parallel computations onto linear array, shared memory, and host-satellite systems figures prominently. This paper extends that work first by showing how to improve existing serial mapping algorithms. These improvements have significantly lower time and space complexities: in one case a published O(nm sup 3) time algorithm for mapping m modules onto n processors is reduced to an O(nm log m) time complexity, and its space requirements reduced from O(nm sup 2) to O(m). Run time complexity is further reduced with parallel mapping algorithms based on these improvements, which run on the architecture for which they create the mappings.

Maintaining relationships is critical in network's success.

PubMed

Huerta, Timothy

2006-01-01

As the authors of the lead paper recognize, networks have become an increasingly popular form of organizing, both in the delivery of public services and within political arenas. A network is an arrangement of individuals and/or organizations that are linked through connections that range from informal relationships to formally agreed protocols. Networks have proved useful in addressing complex and intractable problems that require a holistic approach to identifying and implementing long-term solutions. They succeed in situations where hierarchies and "silo-based" systems have failed, and are particularly valuable in facilitating the transfer of resources and knowledge across sectoral and organizational boundaries.

The Angelchik prosthesis for gastro-oesophageal reflux: symptomatic and objective assessment.

PubMed Central

Weaver, R. M.; Temple, J. G.

1985-01-01

Twenty-three patients with intractable gastro-oesophageal reflux were treated by insertion of the Angelchik antireflux prosthesis. Good symptomatic relief was achieved in over 80% of patients reviewed up to 28 months after operation and there was marked resolution of oesophagitis as seen on endoscopy. Oesophageal manometry and pH studies performed preoperatively and at 3 and 12 months after operation, showed a significant increase in lower oesophageal sphincter pressure with decreased acid reflux. Some technical problems were encountered, but the prosthesis is potentially a simple and effective means of controlling gastro-oesophageal reflux. Images Fig. 1 PMID:4051424

Scalable implementation of boson sampling with trapped ions.

PubMed

Shen, C; Zhang, Z; Duan, L-M

2014-02-07

Boson sampling solves a classically intractable problem by sampling from a probability distribution given by matrix permanents. We propose a scalable implementation of boson sampling using local transverse phonon modes of trapped ions to encode the bosons. The proposed scheme allows deterministic preparation and high-efficiency readout of the bosons in the Fock states and universal mode mixing. With the state-of-the-art trapped ion technology, it is feasible to realize boson sampling with tens of bosons by this scheme, which would outperform the most powerful classical computers and constitute an effective disproof of the famous extended Church-Turing thesis.

Adolescent suicide as a public health threat.

PubMed

Bloch, D S

1999-01-01

Adolescent suicide patterns. To raise awareness of the seriousness of adolescent suicidal behavior by reviewing international research on adolescent suicide and evaluating the prospects for identification and intervention. Published literature. Adolescent suicide research is complicated and often contradictory, but it does provide some insight into prevalence, risk factors, screening tools, and interventions. For completers, the problem may be intractable. But a few broad-based identification and prevention efforts show promise, and psychotherapy is a proven success. Even if suicide rates remain high, treatment of attempters should prevent further self-harm and reduce the completion rate, and thus should be funded.

Constellation Coverage Analysis

NASA Technical Reports Server (NTRS)

Lo, Martin W. (Compiler)

1997-01-01

The design of satellite constellations requires an understanding of the dynamic global coverage provided by the constellations. Even for a small constellation with a simple circular orbit propagator, the combinatorial nature of the analysis frequently renders the problem intractable. Particularly for the initial design phase where the orbital parameters are still fluid and undetermined, the coverage information is crucial to evaluate the performance of the constellation design. We have developed a fast and simple algorithm for determining the global constellation coverage dynamically using image processing techniques. This approach provides a fast, powerful and simple method for the analysis of global constellation coverage.

Drug advertising: the right or wrong prescription for our ailments?

PubMed

Brodie, Mollyann; Levitt, Larry

2002-11-01

As the cost of health care--particularly prescription drugs--is rising at a rate that has not been seen in a decade, the United States finds itself once again searching for new solutions to what has, until now, been an intractable problem. Drug advertising, which has almost become part of the social fabric in the United States, is an appealing and visible target. Critics point to pharmaceutical companies boosting profits by pitching pills, whereas advocates talk of empowering patients with information. With a topic that is so dominated by money and politics, it is sometimes hard to tell who is correct.

Dynamical Systems and Jung, with a Note on Language

ERIC Educational Resources Information Center

Barrett, Bruce E.

2011-01-01

Comments on the original article "Rethinking intractable conflict: The perspective of dynamical systems," by R. R. Vallacher, P. T. Coleman, A. Nowak, and L. Bui-Wrzosinska. Vallacher et al presented an intriguing description of dynamical systems theory as applied to the understanding of intractable conflicts ranging from the intrapsychic to the…

Spinal epidural neurostimulation for treatment of acute and chronic intractable pain: initial and long term results.

PubMed

Richardson, R R; Siqueira, E B; Cerullo, L J

1979-09-01

Spinal epidural neurostimulation, which evolved from dorsal column stimulation, has been found to be effective in the treatment of acute and chronic intractable pain. Urban and Hashold have shown that it is a safe, simplified alternative to dorsal column stimulation, especially because laminectomy is not required if the electrodes are inserted percutaneously. Percutaneous epidural neurostimulation is also advantageous because there can be a diagnostic trial period before permanent internalization and implantation. This diagnostic and therapeutic modality has been used in 36 patients during the past 3 years at Northwestern Memorial Hospital. Eleven of these patients had acute intractable pain, which was defined as pain of less than 1 year in duration. Initial postimplantation results from the 36 patients indicate that spinal epidural neurostimulation is most effective in treating the intractable pain of diabetes, arachnoiditis, and post-traumatic and postamputation neuroma. Long term follow-up, varying from 1 year to 3 years postimplantation in the 20 initially responding patients, indicates that the neurostimulation continues to provide significant pain relief (50% or greater) in a majority of the patients who experienced initial significant pain relief.

[Chronological analysis of individually linked data for patients with intractable disease receiving public financial aid for treatment].

PubMed

Shibazaki, Satomi; Nagai, Masaki; Fuchigami, Hiroshi; Nishina, Motoko; Ohta, Akiko; Kawamura, Takashi; Ohno, Yoshiyuki

2005-12-01

Nationwide surveys of intractable disease patients receiving public financial aid for treatment were performed by Research Committee for Epidemiology of Intractable Disease (Ministry of Health and Welfare, Japan) 4 times in the past, in 1984, 1988, 1992 and 1997. The purpose of the present study was to clarify the features of continuance with intractable disease patients receiving public financial aid for treatment. Individual information collected by each nationwide survey was linked using the disease, the residence, the sex, and the birth date. The proportion of intractable disease patients according to receipt duration, kind of medical insurance, sex and age was calculated with reference to the disease and an estimation of the receipt persistence rate was calculated for every year. Moreover, in consideration of variation in the data, average receipt persistence rates over years were also calculated. According to observation on individual patient's follow up, the proportion for which financial aid was discontinued within four years was 25%, while 70% continued receiving aid for at least four years and some 55% for eight or nine years. The proportion of those who continue receiving support long-term is high about the so-called autoimmune diseases, such as systemic lupus erythematosus, Behçet's disease, and the aortic syndrome. In contrast, with diseases having a poor prognosis, such as fulminant hepatitis, amyloidosis, and amyotrophic lateral sclerosis, periods of continuance are short. The proportion needing long-term continuation is higher in women than in men, especially with diseases which have long been eligible for support. However, with diseases for which receipt was started recently, there is a tendency for persistence to be higher in men than in women. With reform of insurance systems, including the medical system for intractable diseases, it is predicted that receipt continuation will change with alteration of social factors, and it is necessary to monitor receipt continuation carefully from now on.

Children value informativity over logic in word learning.

PubMed

Ramscar, Michael; Dye, Melody; Klein, Joseph

2013-06-01

The question of how children learn the meanings of words has long puzzled philosophers and psychologists. As Quine famously pointed out, simply hearing a word in context reveals next to nothing about its meaning. How then do children learn to understand and use words correctly? Here, we show how learning theory can offer an elegant solution to this seemingly intractable puzzle in language acquisition. From it, we derived formal predictions about word learning in situations of Quinean ambiguity, and subsequently tested our predictions on toddlers, undergraduates, and developmental psychologists. The toddlers' performance was consistent both with our predictions and with the workings of implicit mechanisms that can facilitate the learning of meaningful lexical systems. Adults adopted a markedly different and likely suboptimal strategy. These results suggest one explanation for why early word learning can appear baffling: Adult intuitions may be a poor source of insight into how children learn.

Adding to the Education Debt: Depressive Symptoms Mediate the Association between Racial Discrimination and Academic Performance in African Americans

PubMed Central

English, Devin; Lambert, Sharon F.; Ialongo, Nicholas S.

2015-01-01

Although the United States faces a seemingly intractable divide between white and African American academic performance, there remains a dearth of longitudinal research investigating factors that work to maintain this gap. The present study examined whether racial discrimination predicted the academic performance of African American students through its effect on depressive symptoms. Participants were a community sample of African American adolescents (N = 495) attending urban public schools from grade 7 to grade 9 (Mage = 12.5). Structural equation modeling revealed that experienced racial discrimination predicted increases in depressive symptoms 1 year later, which, in turn, predicted decreases in academic performance the following year. These results suggest that racial discrimination continues to play a critical role in the academic performance of African American students and, as such, contributes to the maintenance of the race-based academic achievement gap in the United States. PMID:27425564

Renal Denervation: Intractable Hypertension and Beyond

PubMed Central

Ariyanon, Wassawon; Mao, Huijuan; Adýbelli, Zelal; Romano, Silvia; Rodighiero, Mariapia; Reimers, Bernhard; La Vecchia, Luigi; Ronco, Claudio

2014-01-01

Background Hypertension continues to be a major burden of public health concern despite the recent advances and proven benefit of pharmacological therapy. A certain subset of patients has hypertension resistant to maximal medical therapy and appropriate lifestyle measures. A novel catheter-based technique for renal denervation (RDN) as a new therapeutic avenue has great promise for the treatment of refractory hypertension. Summary This review included the physiology of the renal sympathetic nervous system and the renal nerve anatomy. Furthermore, the RDN procedure, technology systems, and RDN clinical trials as well as findings besides antihypertensive effects were discussed. Findings on safety and efficacy seem to suggest that renal sympathetic denervation could be of therapeutic benefit in refractory hypertensive patients. Despite the fast pace of development in RDN therapies, only initial and very limited clinical data are available. Large gaps in knowledge concerning the long-term effects and consequences of RDN still exist, and solid, randomized data are warranted. PMID:24847331

Levosimendan in Critical Illness: A Literature Review

PubMed Central

Pierrakos, Charalampos; Velissaris, Dimitrios; Franchi, Federico; Muzzi, Luigi; Karanikolas, Menelaos; Scolletta, Sabino

2014-01-01

Levosimendan, the active enantiomer of simendan, is a calcium sensitizer developed for treatment of decompensated heart failure, exerts its effects independently of the beta adrenergic receptor and seems beneficial in cases of severe, intractable heart failure. Levosimendan is usually administered as 24-h infusion, with or without a loading dose, but dosing needs adjustment in patients with severe liver or renal dysfunction. Despite several promising reports, the role of levosimendan in critical illness has not been thoroughly evaluated. Available evidence suggests that levosimendan is a safe treatment option in critically ill patients and may reduce mortality from cardiac failure. However, data from well-designed randomized controlled trials in critically ill patients are needed to validate or refute these preliminary conclusions. This literature review is an attempt to synthesize available evidence on the role and possible benefits of levosimendan in critically ill patients with severe heart failure. PMID:24578748

Aircraft transfer of pediatric patients with intractable cardiac or airway problems – single-institutional experience of a specialty hospital.

PubMed

Ando, Makoto; Takahashi, Yukihiro; Park, In-Sam; Tomoike, Hitonobu

2015-01-01

There is currently a well-established network for the allocation of donor organs for transplantation in Japan, and emergency patients are often transported by the "Doctor Helicopter". However, interhospital transfer of patients, which can require aircraft with specialized equipment, depends on arrangement by each responsible hospital. Since 2009 there were 41 interhospital aviation transfers of pediatric patients with intractable cardiac or airway diseases seeking surgical treatment at Sakakibara Heart Institute. Of these, 22 were newborns, 21 were on continuous drip infusion and 14 on mechanical ventilator support. In 15 cases (36.6%), a commercial airliner was used, with the remaining using chartered emergency aircraft (eg, local fire department helicopter, Self-Defense-Forces of Japan and the Doctor Helicopter). The median transfer time was 239 min for commercial airliners, 51 min for chartered aircraft departing directly from the referring hospital and 120.5 min for chartered aircraft departing from a nearby location. The efficiency of the transfer exemplified by the percentage of the time on board the aircraft was significantly lower for commercial airliners compared with chartered emergency aircraft. Further efforts and cooperation with government are required to obtain geographically uniform availability of carriers with optimal medical equipment to improve pediatric patient outcomes.

Long-term usage of narcotic analgesics by chronic intractable noncancer pain patients in Taiwan from 2003 to 2012.

PubMed

Cheng, I-Chen; Chang, Chih-Shiuh; Tsay, Wen-Ing

2016-09-01

Chronic pain is a common and important medical problem worldwide. Patients with chronic intractable noncancer pain (CINCP) are treated primarily with narcotics. We analyzed the characteristics of patients with CINCP and the pain prescriptions of Taiwan's physicians. We enrolled 644 patients from 66 hospitals approved by the Taiwan Food and Drug Administration to use long-term narcotics for CINCP between 2003 and 2012. The majority (61.8%) of patients were 40-49-year-old men who had been treated with pethidine more often than with fentanyl in the 20-49 years age group. More than 50% of CINCP patients live in northern Taiwan, and most were treated in the department of pain; the major diagnosis (men 28.9%; women 27.7%) was neuropathy. The most frequently prescribed single analgesic was morphine (52.2%); the most frequently prescribed two-drug combination was morphine plus fentanyl (50.8%). Pethidine, however, was the most frequently prescribed analgesic in the neurology (78.0%) and plastic surgery (50.0%) departments. To decrease malaise and addiction in patients with CINCP, Taiwan's physicians need more education on narcotic analgesics, and greater professional cooperation to develop therapeutic guidelines that will improve pain care for patients with CINCP. Copyright © 2015. Published by Elsevier B.V.

Quantum supremacy in constant-time measurement-based computation: A unified architecture for sampling and verification

NASA Astrophysics Data System (ADS)

Miller, Jacob; Sanders, Stephen; Miyake, Akimasa

2017-12-01

While quantum speed-up in solving certain decision problems by a fault-tolerant universal quantum computer has been promised, a timely research interest includes how far one can reduce the resource requirement to demonstrate a provable advantage in quantum devices without demanding quantum error correction, which is crucial for prolonging the coherence time of qubits. We propose a model device made of locally interacting multiple qubits, designed such that simultaneous single-qubit measurements on it can output probability distributions whose average-case sampling is classically intractable, under similar assumptions as the sampling of noninteracting bosons and instantaneous quantum circuits. Notably, in contrast to these previous unitary-based realizations, our measurement-based implementation has two distinctive features. (i) Our implementation involves no adaptation of measurement bases, leading output probability distributions to be generated in constant time, independent of the system size. Thus, it could be implemented in principle without quantum error correction. (ii) Verifying the classical intractability of our sampling is done by changing the Pauli measurement bases only at certain output qubits. Our usage of random commuting quantum circuits in place of computationally universal circuits allows a unique unification of sampling and verification, so they require the same physical resource requirements in contrast to the more demanding verification protocols seen elsewhere in the literature.

Cyclodialysis ab interno as a surgical approach to intractable glaucoma.

PubMed

Jordan, Jens F; Dietlein, Thomas S; Dinslage, Sven; Lüke, Christoph; Konen, Walter; Krieglstein, Günter K

2007-08-01

In glaucoma filtration surgery, the problem of subconjunctival scarring has still not been satisfactorily solved. Suprachoroidal drainage of aqueous humour offers a promising, alternative option for intractable glaucoma. We here present a clinical study on the surgical approach of gonioscopic cyclodialysis ab interno. Twenty-eight eyes of 20 patients with intractable glaucoma were included in this prospective, consecutive, case-control study. The eyes had had a mean of 4.4 +/- 2.4 previous antiglaucomatous interventions. Baseline intraocular pressure (IOP) was 34.3 +/- 10.5 mmHg despite maximum therapy. Under gonioscopic control, cyclodialysis ab interno was performed over two clock times to gain access to the suprachoroidal space. No additional trabecular meshwork surgery was performed. Success was defined as a lowering of IOP to below 21 mmHg without the need for further medication or intervention. Mean postoperative IOP was 14.6 +/- 12.4 mmHg. Mean follow-up (FU) for all eyes was 121.8 days. After a mean of 60 days, 21 eyes (75%) needed further surgical intervention. Qualified success was seen in four eyes (14.3%), with a mean FU of 383.6 days. Three eyes (10.7%) showed absolute success after a mean FU period of 202.7 days. In our series, we obtained the best results for phakic eyes, followed by pseudophakic and aphakic eyes. The results of this study do not provide convincing evidence of the functional efficacy of cyclodialysis ab interno. Nevertheless, the technique is easy to perform and offers safe and atraumatic access to the resorptive capability of the choroid. Conjunctival manipulation is avoided. Contrary to reports in the current literature, in our series, the best results were obtained for phakic eyes, though the small number of eyes included does not allow reliable statistics. Further studies will need to focus on the use of different space-retaining substances or a widening of the cyclodialysis cleft to improve surgical outcome.

Developing Agency through Peacebuilding in the Midst of Intractable Conflict: The Case of Israel and Palestine

ERIC Educational Resources Information Center

Plonski, Sharri

2005-01-01

This paper discusses the presence of "peacebuilding islands" within civil society as potential agents of transformation in the midst of intractable conflict. Focusing on the particular case of the Israeli-Palestinian conflict, the argument stems from a deconstruction of the legacy of national myopia perpetuated through social and…

Internationalization under Intractable Conflict: The Influence of National Conflict on Israeli Higher Education Institutions' Internationalization Efforts

ERIC Educational Resources Information Center

Yemini, Miri

2017-01-01

Intractable conflicts are usually defined as long-lasting, violent, intergroup ones perceived as having no foreseen solutions. Such conflicts heavily affect the societies involved, which invest massive resources in all issues related to the conflict, including various educational elements. Regardless of the context of national conflict,…

Dual Pathology in Rasmussen's Encephalitis: A Report of Coexistent Focal Cortical Dysplasia and Review of the Literature.

PubMed

Prayson, Richard A

2012-01-01

Rasmussen's encephalitis is a well-established, albeit rare cause of medically intractable epilepsy. In a small number of Rasmussen's cases, a second pathology is identified, which independently can cause medically intractable seizures (dual pathology). This paper documents a case of a 13-year-old male who presented with medically intractable epilepsy. The patient underwent a series of surgical resections, early on resulting in a diagnosis of focal cortical dysplasia and later yielding a diagnosis of coexistent Rasmussen's encephalitis, marked by chronic inflammation, microglial nodules, and focal cortical atrophy, combined with focal cortical dysplasia (Palmini et al. type IIA, ILAE type IIA). The literature on dual pathology in the setting of Rasmussen's encephalitis is reviewed.

Dual Pathology in Rasmussen's Encephalitis: A Report of Coexistent Focal Cortical Dysplasia and Review of the Literature

PubMed Central

Prayson, Richard A.

2012-01-01

Rasmussen's encephalitis is a well-established, albeit rare cause of medically intractable epilepsy. In a small number of Rasmussen's cases, a second pathology is identified, which independently can cause medically intractable seizures (dual pathology). This paper documents a case of a 13-year-old male who presented with medically intractable epilepsy. The patient underwent a series of surgical resections, early on resulting in a diagnosis of focal cortical dysplasia and later yielding a diagnosis of coexistent Rasmussen's encephalitis, marked by chronic inflammation, microglial nodules, and focal cortical atrophy, combined with focal cortical dysplasia (Palmini et al. type IIA, ILAE type IIA). The literature on dual pathology in the setting of Rasmussen's encephalitis is reviewed. PMID:23056977

Early growth and development impairments in patients with ganglioside GM3 synthase deficiency.

PubMed

Wang, H; Wang, A; Wang, D; Bright, A; Sency, V; Zhou, A; Xin, B

2016-05-01

Ganglioside GM3 synthase is a key enzyme involved in the biosynthesis of gangliosides. GM3 synthase deficiency (GSD) causes a complete absence of GM3 and all downstream biosynthetic derivatives. The individuals affected by this disorder manifest severe irritability, intractable seizures and profound intellectual disability. However, we have found that most newborns seem symptom-free for a period of time after birth. In order to further understand the onset of the disease, we investigated the early growth and development of patients with this condition through this study. We compared 37 affected individuals with their normal siblings and revealed that all children with GSD had relatively normal intrauterine growth and development, as their weight, length and head circumference were similar to their normal siblings at birth. However, the disease progresses quickly after birth and causes significant constitutional impairments of growth and development by 6 months of age. Neither breastfeeding nor gastrostomy tube placement made significant difference on growth and development as all groups of patients showed the similar pattern. We conclude that GSD causes significant postnatal growth and developmental impairments and the amount of gangliosides in breast milk and general nutritional intervention do not seem to alter these outcomes. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Defining mindfulness by how poorly I think I pay attention during everyday awareness and other intractable problems for psychology's (re)invention of mindfulness: comment on Brown et al. (2011).

PubMed

Grossman, Paul

2011-12-01

The Buddhist construct of mindfulness is a central element of mindfulness-based interventions and derives from an age-old systematic phenomenological program to investigate subjective experience. Recent enthusiasm for "mindfulness" in psychology has resulted in proliferation of self-report inventories that purport to measure mindful awareness as a trait. This paper addresses a number of intractable issues regarding these scales, in general, and also specifically highlights vulnerabilities of the adult and adolescent forms of the Mindfulness Attention Awareness Scale. These problems include (a) lack of available external referents for determining the construct validity of these inventories, (b) inadequacy of content validity of measures, (c) lack of evidence that self-reports of mindfulness competencies correspond to actual behavior and evidence that they do not, (d) lack of convergent validity among different mindfulness scales, (e) inequivalence of semantic item interpretation among different groups, (f) response biases related to degree of experience with mindfulness practice, (g) conflation of perceived mindfulness competencies with valuations of importance or meaningfulness, and (h) inappropriateness of samples employed to validate questionnaires. Current self-report attempts to measure mindfulness may serve to denature, distort, and banalize the meaning of mindful awareness in psychological research and may adversely affect further development of mindfulness-based interventions. Opportunities to enrich positivist Western psychological paradigms with a detailed and complex Buddhist phenomenology of the mind are likely to require a depth of understanding of mindfulness that, in turn, depends upon direct and long-term experience with mindfulness practice. Psychologists should consider pursuing this avenue before attempting to characterize and quantify mindfulness.

Tractable Experiment Design via Mathematical Surrogates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, Brian J.

This presentation summarizes the development and implementation of quantitative design criteria motivated by targeted inference objectives for identifying new, potentially expensive computational or physical experiments. The first application is concerned with estimating features of quantities of interest arising from complex computational models, such as quantiles or failure probabilities. A sequential strategy is proposed for iterative refinement of the importance distributions used to efficiently sample the uncertain inputs to the computational model. In the second application, effective use of mathematical surrogates is investigated to help alleviate the analytical and numerical intractability often associated with Bayesian experiment design. This approach allows formore » the incorporation of prior information into the design process without the need for gross simplification of the design criterion. Illustrative examples of both design problems will be presented as an argument for the relevance of these research problems.« less

A linguistic geometry for space applications

NASA Technical Reports Server (NTRS)

Stilman, Boris

1994-01-01

We develop a formal theory, the so-called Linguistic Geometry, in order to discover the inner properties of human expert heuristics, which were successful in a certain class of complex control systems, and apply them to different systems. This research relies on the formalization of search heuristics of high-skilled human experts which allow for the decomposition of complex system into the hierarchy of subsystems, and thus solve intractable problems reducing the search. The hierarchy of subsystems is represented as a hierarchy of formal attribute languages. This paper includes a formal survey of the Linguistic Geometry, and new example of a solution of optimization problem for the space robotic vehicles. This example includes actual generation of the hierarchy of languages, some details of trajectory generation and demonstrates the drastic reduction of search in comparison with conventional search algorithms.

Elucidating reaction mechanisms on quantum computers.

PubMed

Reiher, Markus; Wiebe, Nathan; Svore, Krysta M; Wecker, Dave; Troyer, Matthias

2017-07-18

With rapid recent advances in quantum technology, we are close to the threshold of quantum devices whose computational powers can exceed those of classical supercomputers. Here, we show that a quantum computer can be used to elucidate reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example. We discuss how quantum computers can augment classical computer simulations used to probe these reaction mechanisms, to significantly increase their accuracy and enable hitherto intractable simulations. Our resource estimates show that, even when taking into account the substantial overhead of quantum error correction, and the need to compile into discrete gate sets, the necessary computations can be performed in reasonable time on small quantum computers. Our results demonstrate that quantum computers will be able to tackle important problems in chemistry without requiring exorbitant resources.

Elucidating reaction mechanisms on quantum computers

PubMed Central

Reiher, Markus; Wiebe, Nathan; Svore, Krysta M.; Wecker, Dave; Troyer, Matthias

2017-01-01

With rapid recent advances in quantum technology, we are close to the threshold of quantum devices whose computational powers can exceed those of classical supercomputers. Here, we show that a quantum computer can be used to elucidate reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example. We discuss how quantum computers can augment classical computer simulations used to probe these reaction mechanisms, to significantly increase their accuracy and enable hitherto intractable simulations. Our resource estimates show that, even when taking into account the substantial overhead of quantum error correction, and the need to compile into discrete gate sets, the necessary computations can be performed in reasonable time on small quantum computers. Our results demonstrate that quantum computers will be able to tackle important problems in chemistry without requiring exorbitant resources. PMID:28674011

Elucidating reaction mechanisms on quantum computers

NASA Astrophysics Data System (ADS)

Reiher, Markus; Wiebe, Nathan; Svore, Krysta M.; Wecker, Dave; Troyer, Matthias

2017-07-01

With rapid recent advances in quantum technology, we are close to the threshold of quantum devices whose computational powers can exceed those of classical supercomputers. Here, we show that a quantum computer can be used to elucidate reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example. We discuss how quantum computers can augment classical computer simulations used to probe these reaction mechanisms, to significantly increase their accuracy and enable hitherto intractable simulations. Our resource estimates show that, even when taking into account the substantial overhead of quantum error correction, and the need to compile into discrete gate sets, the necessary computations can be performed in reasonable time on small quantum computers. Our results demonstrate that quantum computers will be able to tackle important problems in chemistry without requiring exorbitant resources.

Defining intractability: comparisons among published definitions.

PubMed

Berg, Anne T; Kelly, Molly M

2006-02-01

Intractable epilepsy is the focus of much research; however, this concept is defined in no single way. Individual studies use different definitions, creating difficulties for comparisons of results across studies. A head-to-head comparison of definitions could highlight these differences and motivate the development of consensus guidelines. Within a single prospective study of 613 children in Connecticut with newly diagnosed epilepsy (1993-1997), six different published definitions or indicators for intractability were applied and compared. All definitions were assessed at various times within the first 5 years after diagnosis, with the exact timing reflecting how they were used in their initial reports. Observed and chance-adjusted agreement (kappa) were computed. The associations of each definition with remission status 7-10 years after diagnosis were quantified with a relative risk. Depending on the specific definition, the epilepsy of 9-24% of children was considered intractable. Observed agreements among the definitions ranged from a low of 0.83 to a high of 0.96. Kappas ranged from low of 0.45 to 0.79. More similar definitions had higher levels of agreement. All definitions were strongly associated with remission status as of last follow-up. Agreement among the different definitions is strong but imperfect. All definitions were significantly associated with longer-term outcome. No single preferred definition of intractable epilepsy exists. Some discussion within the field of epilepsy and a consensus process should be considered as a future step for enhancing comparability of research efforts and clinical guidelines. Consideration should be given to whether a single definition will suit all purposes or whether different types of definitions are needed for different purposes.

Environmental Enrichment Mitigates Detrimental Cognitive Effects of Ketogenic Diet in Weanling Rats.

PubMed

Scichilone, John M; Yarraguntla, Kalyan; Charalambides, Ana; Harney, Jacob P; Butler, David

2016-09-01

For decades, the ketogenic diet has been an effective treatment of intractable epilepsy in children. Childhood epilepsy is pharmacoresistant in 25-40 % of patients taking the current prescribed medications. Chronic seizure activity has been linked to deficits in cognitive function and behavioral problems which negatively affect the learning abilities of the child. Recent studies suggest the ketogenic diet (KD), a high fat with low carbohydrate and protein diet, has adverse effects on cognition in weanling rats. The diet reduces circulating glucose levels to where energy metabolism is converted from glycolysis to burning fat and generating ketone bodies which has been suggested as a highly efficient source of energy for the brain. In contrast, when weanling rats are placed in an enriched environment, they exhibit increased spatial learning, memory, and neurogenesis. Thus, this study was done to determine if weanling rats being administered a KD in an environmental enrichment (EE) would still exhibit the negative cognitive effects of the diet previously observed. The present study suggests that an altered environment is capable of reducing the cognitive deficits in weanling rats administered a KD. Learning was improved with an EE. The effect of diet and environment on anxiety and depression suggests a significant reduction in anxiety with enrichment rearing. Interestingly, circulating energy substrate levels were increased in the EE groups along with brain-derived neurotrophic factor despite the least changes in weight gain. In light of numerous studies using KDs that seemingly have adverse effects on cognition, KD-induced reductions in excitotoxic events would not necessarily eliminate that negative aspect of seizures.

Cultivating creativity in conservation science.

PubMed

Aslan, Clare E; Pinsky, Malin L; Ryan, Maureen E; Souther, Sara; Terrell, Kimberly A

2014-04-01

Conservation practitioners and scientists are often faced with seemingly intractable problems in which traditional approaches fail. While other sectors (e.g., business) frequently emphasize creative thinking to overcome complex challenges, creativity is rarely identified as an essential skill for conservationists. Yet more creative approaches are urgently needed in the effort to sustain Earth's biodiversity. We identified 4 strategies to develop skills in creative thinking and discuss underlying research and examples supporting each strategy. First, by breaking down barriers between disciplines and surrounding oneself with unfamiliar people, concepts, and perspectives, one can expand base knowledge and experiences and increase the potential for new combinations of ideas. Second, by meeting people where they are (both literally and figuratively), one exposes oneself to new environments and perspectives, which again broadens experiences and increases ability to communicate effectively with stakeholders. Third, by embracing risk responsibly, one is more likely to develop new, nontraditional solutions and be open to high-impact outcomes. Finally, by following a cycle of learning, struggle, and reflection, one can trigger neurophysiological changes that allow the brain to become more creative. Creativity is a learned trait, rather than an innate skill. It can be actively developed at both the individual and institutional levels, and learning to navigate the relevant social and practical barriers is key to the process. To maximize the success of conservation in the face of escalating challenges, one must take advantage of what has been learned from other disciplines and foster creativity as both a professional skill and an essential component of career training and individual development. © 2013 Society for Conservation Biology.

Narrative spaces between intractability outside the clinic.

PubMed

Wiederhold, Anna M

2014-01-01

In this essay, the author reflects on her experience conducting field research outside an abortion clinic amid volatile protests and counterprotests. She identifies moments of convergence in the oppositional groups' narrative explanations for participating in the weekly protests, and contemplates the possibilities for dialogue in these sorts of intractable conflicts. She concludes with reflections on communication scholars' roles in engaging with polarizing health narratives.

CDKL5 mutations in boys with severe encephalopathy and early-onset intractable epilepsy.

PubMed

Elia, M; Falco, M; Ferri, R; Spalletta, A; Bottitta, M; Calabrese, G; Carotenuto, M; Musumeci, S A; Lo Giudice, M; Fichera, M

2008-09-23

To search for CDKL5 gene mutations in boys presenting with severe early-onset encephalopathy and intractable epilepsy, a clinical picture very similar to that already described in girls with CDKL5 mutations. Eight boys (age range 3-16 years, mean age 8.5 years, SD 4.38) with severe or profound mental retardation and early-onset intractable seizures were selected for CDKL5 gene mutation screening by denaturing high-performance liquid chromatography analysis. We found three unrelated boys carrying three different missense mutations of the CDKL5 gene: c.872G>A (p.C291Y), c.863C>T (p.T288I), and c.533G>C (p.R178P). They presented early-onset, polymorphous, and drug-resistant seizures, mostly myoclonic and tonic or spasms. EEG showed epileptiform abnormalities which were multifocal during wakefulness, and pseudoperiodic bisynchronous during sleep. This study describes three boys carrying CDKL5 missense mutations and their detailed clinical and EEG data, and indicates that CDKL5 gene mutations may represent a cause of severe or profound mental retardation and early-onset intractable seizures, also in boys. Screening for CDKL5 mutations is strongly recommended in individuals with these clinical features.

A case report of dexmedetomidine used to treat intractable pain and delirium in a tertiary palliative care unit.

PubMed

Hilliard, Neil; Brown, Stuart; Mitchinson, Steve

2015-03-01

This case report describes an end-stage cancer patient with intractable neuropathic pain and delirium who was successfully managed during the last 3 weeks of her life with a continuous subcutaneous infusion of dexmedetomidine. A 55-year-old woman with locally advanced cervical cancer and uncontrolled pelvic pain was admitted to a tertiary palliative care unit for pain management. As her disease progressed, the patient's pelvic pain intensified despite treatment with methadone, gabapentin, ketamine, and hydromorphone administered by continuous subcutaneous infusion plus frequent breakthrough doses of hydromorphone and sufentanil. A continuous subcutaneous infusion of dexmedetomidine was started and titrated to achieve pain relief. The patient's pain and delirium cleared. The treatment was successful in fulfilling the patient's goal of care: not to be deeply and continuously sedated, but to be rousable and of clear mind while still having good pain control. Dexmedetomidine is a potentially useful medication for the targeted treatment of intractable pain and delirium in the tertiary palliative care environment. Future research is required to compare dexmedetomidine infusion to standard treatment with midazolam infusion for treatment of intractable symptoms in the palliative care environment. © The Author(s) 2014.

[Gabapentin in the treatment of chronic intractable pain].

PubMed

Gustorff, B; Nahlik, G; Spacek, A; Kress, H G

2002-02-01

Gabapentin has been shown to reduce pain associated with diabetic neuropathia and postherpetic neuralgia. To date it is not known, whether gabapentin is generally effective in other types of pain. It was therefore the aim to study gabapentin in patients suffering from intractable pain with respect to efficacy, predictive factors and side effects. Retrospective analysis of the data sheet of pretreated patients suffering from intractable pain and treated with gabapentin as a third line drug at a university pain clinic. Pain intensity (visual analogue scale, VAS 0 -10 cm), pain characteristics, diagnosis, pre- and co-treatment, and side effects were assessed. Response to treatment was defined as a 50% reduction in pain or a pain intensity of VAS

The Use of Hemoglobin Vesicles for Delivering Medicinal Gas for the Treatment of Intractable Disorders.

PubMed

Taguchi, Kazuaki; Yamasaki, Keishi; Sakai, Hiromi; Maruyama, Toru; Otagiri, Masaki

2017-09-01

Bioactive gaseous molecules, such as oxygen (O 2 ) and carbon monoxide (CO), are essential elements for most living organisms to maintain their homeostasis and biological activities. An accumulating body of evidence suggests that such molecules can be used in clinics as a medical gas in the treatment of various intractable disorders. Recent developments in hemoglobin-encapsulated liposomes, namely hemoglobin vesicles (HbV), possess great potential for retaining O 2 and CO and could lead to strategies for the development of novel pharmacological agents as medical gas donors. HbV with either O 2 or CO bound to it has been demonstrated to have therapeutic potential for treating certain intractable disorders and has the possibility to serve as diagnostic and augmenting product by virtue of unique physicochemical characteristics of HbV. The present review provides an overview of the present status of the use of O 2 - or CO-binding HbV in experimental animal models of intractable disorders and discusses prospective clinical applications of HbV as a medical gas donor. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Drosophila as a model for intractable epilepsy: gilgamesh suppresses seizures in para(bss1) heterozygote flies.

PubMed

Howlett, Iris C; Rusan, Zeid M; Parker, Louise; Tanouye, Mark A

2013-08-07

Intractable epilepsies, that is, seizure disorders that do not respond to currently available therapies, are difficult, often tragic, neurological disorders. Na(+) channelopathies have been implicated in some intractable epilepsies, including Dravet syndrome (Dravet 1978), but little progress has been forthcoming in therapeutics. Here we examine a Drosophila model for intractable epilepsy, the Na(+) channel gain-of-function mutant para(bss1) that resembles Dravet syndrome in some aspects (parker et al. 2011a). In particular, we identify second-site mutations that interact with para(bss1), seizure enhancers, and seizure suppressors. We describe one seizure-enhancer mutation named charlatan (chn). The chn gene normally encodes an Neuron-Restrictive Silencer Factor/RE1-Silencing Transcription factor transcriptional repressor of neuronal-specific genes. We identify a second-site seizure-suppressor mutation, gilgamesh (gish), that reduces the severity of several seizure-like phenotypes of para(bss1)/+ heterozygotes. The gish gene normally encodes the Drosophila ortholog of casein kinase CK1g3, a member of the CK1 family of serine-threonine kinases. We suggest that CK1g3 is an unexpected but promising new target for seizure therapeutics.

Joint terminals and relay optimization for two-way power line information exchange systems with QoS constraints

NASA Astrophysics Data System (ADS)

Wu, Xiaolin; Rong, Yue

2015-12-01

The quality-of-service (QoS) criteria (measured in terms of the minimum capacity requirement in this paper) are very important to practical indoor power line communication (PLC) applications as they greatly affect the user experience. With a two-way multicarrier relay configuration, in this paper we investigate the joint terminals and relay power optimization for the indoor broadband PLC environment, where the relay node works in the amplify-and-forward (AF) mode. As the QoS-constrained power allocation problem is highly non-convex, the globally optimal solution is computationally intractable to obtain. To overcome this challenge, we propose an alternating optimization (AO) method to decompose this problem into three convex/quasi-convex sub-problems. Simulation results demonstrate the fast convergence of the proposed algorithm under practical PLC channel conditions. Compared with the conventional bidirectional direct transmission (BDT) system, the relay-assisted two-way information exchange (R2WX) scheme can meet the same QoS requirement with less total power consumption.

Cooperative Surveillance and Pursuit Using Unmanned Aerial Vehicles and Unattended Ground Sensors

PubMed Central

Las Fargeas, Jonathan; Kabamba, Pierre; Girard, Anouck

2015-01-01

This paper considers the problem of path planning for a team of unmanned aerial vehicles performing surveillance near a friendly base. The unmanned aerial vehicles do not possess sensors with automated target recognition capability and, thus, rely on communicating with unattended ground sensors placed on roads to detect and image potential intruders. The problem is motivated by persistent intelligence, surveillance, reconnaissance and base defense missions. The problem is formulated and shown to be intractable. A heuristic algorithm to coordinate the unmanned aerial vehicles during surveillance and pursuit is presented. Revisit deadlines are used to schedule the vehicles' paths nominally. The algorithm uses detections from the sensors to predict intruders' locations and selects the vehicles' paths by minimizing a linear combination of missed deadlines and the probability of not intercepting intruders. An analysis of the algorithm's completeness and complexity is then provided. The effectiveness of the heuristic is illustrated through simulations in a variety of scenarios. PMID:25591168

Improving patient safety: lessons from rock climbing.

PubMed

Robertson, Nic

2012-02-01

How to improve patient safety remains an intractable problem, despite large investment and some successes. Academics have argued that the root of the problem is a lack of a comprehensive 'safety culture' in hospitals. Other safety-critical industries such as commercial aviation invest heavily in staff training to develop such a culture, but comparable programmes are almost entirely absent from the health care sector. In rock climbing and many other dangerous activities, the 'buddy system' is used to ensure that safety systems are adhered to despite adverse circumstances. This system involves two or more people using simple checks and clear communication to prevent problems causing harm. Using this system as an example could provide a simple, original and entertaining way of introducing medical students to the idea that human factors are central to ensuring patient safety. Teaching the buddy system may improve understanding and acceptance of other patient safety initiatives, and could also be used by junior doctors as a tool to improve the safety of their practice. © Blackwell Publishing Ltd 2012.

A Case of Intractable Hemophagocytic Syndrome Associated with Systemic Lupus Erythematosus Resistant to Corticosteroids and Intravenous Cyclophosphamide that Was Successfully Treated with Cyclosporine A.

PubMed

Toko, Hirofumi; Tsuboi, Hiroto; Umeda, Naoto; Honda, Fumika; Ohyama, Ayako; Takahashi, Hidenori; Abe, Saori; Yokosawa, Masahiro; Asashima, Hiromitsu; Hagiwara, Shinya; Hirota, Tomoya; Kondo, Yuya; Matsumoto, Isao; Sumida, Takayuki

2018-05-18

Hemophagocytic syndrome (HPS) associated with systemic lupus erythematosus (SLE), dubbed acute lupus hemophagocytic syndrome (ALHS), is an intractable complication of SLE. A 24-year-old man who had been diagnosed with SLE three months previously, presented with fever, rash, hallucination, and pancytopenia accompanied with hyperferritinemia and bone marrow hemophagocytosis. He was diagnosed with ALHS and neuropsychiatric (NP)-SLE. Although 4 courses of methylprednisolone pulse therapy and 1 course of intravenous cyclophosphamide (IVCY) improved his NP-SLE, his ALHS did not respond. However, the addition of cyclosporine A (CsA) led to a rapid remission from ALHS. This suggests the usefulness of CsA in the treatment of intractable, corticosteroid- and IVCY-resistant ALHS.

Noninvasive treatment alternative for intractable startle epilepsy

PubMed Central

Klinkenberg, Sylvia; Ubbink, Sander; Vles, Johannes; de Louw, Anton; van Hall, Mariette Debeij; Scheijen, Dyon; Brokx, Jan

2014-01-01

We describe a treatment alternative for intractable, startle-provoked, epileptic seizures in four children aged between 8 and 14. Three of the four children had symptomatic localization-related epilepsy. They all suffered from intractable epilepsy precipitated by sudden sounds. The fact that seizures tended to occur with high frequency – more than one seizure a day – had a clear impact on daily life. Clinical seizure pattern demonstrated asymmetric tonic posturing in all four children. Three children experienced several seizure types including focal seizure onset. All children had focal neurological signs or learning disabilities or a combination of both. Our noninvasive treatment method using psychoeducational counseling and sound generators was applied in four children, resulting in a seizure frequency reduction of ≥ 50% in two of them. PMID:25667869

Applying social constructionism in the treatment of patients who are intractably aggressive.

PubMed

Caldwell, M F

1994-06-01

Interventions based on the philosophy of social constructionism can be used for the treatment of patients who are intractably aggressive. The interventions are aimed at disrupting common interactive patterns between the patient and treaters in the treatment milieu and replacing them with patterns that do not allow the intractable symptoms to disrupt treatment efforts. Two case examples illustrate the use of this approach with extremely violent inpatients with long histories of unsuccessful interventions. In both cases the treatment included discontinuing certain therapeutic or prosocial interventions; one case involved determining the patient's daily privilege level randomly. The author discusses the advantages and difficulties of such approaches, including the need for staff to reframe their own logical structure and to overcome resistance from different levels of the treatment system.

Investigation of the pathogenesis of autoimmune diseases by iPS cells.

PubMed

Natsumoto, Bunki; Shoda, Hirofumi; Fujio, Keishi; Otsu, Makoto; Yamamoto, Kazuhiko

2017-01-01

The pluripotent stem cells have a self-renewal ability and can be differentiated into theoretically all of cell types. The induced pluripotent stem (iPS) cells overcame the ethical problems of the human embryonic stem (ES) cell, and enable pathologic analysis of intractable diseases and drug discovery. The in vitro disease model using disease-specific iPS cells enables repeated analyses of human cells without influence of environment factors. Even though autoimmune diseases are polygenic diseases, autoimmune disease-specific iPS cells are thought to be a promising tool for analyzing the pathogenesis of the diseases and drug discovery in future.

Language acquisition and use: learning and applying probabilistic constraints.

PubMed

Seidenberg, M S

1997-03-14

What kinds of knowledge underlie the use of language and how is this knowledge acquired? Linguists equate knowing a language with knowing a grammar. Classic "poverty of the stimulus" arguments suggest that grammar identification is an intractable inductive problem and that acquisition is possible only because children possess innate knowledge of grammatical structure. An alternative view is emerging from studies of statistical and probabilistic aspects of language, connectionist models, and the learning capacities of infants. This approach emphasizes continuity between how language is acquired and how it is used. It retains the idea that innate capacities constrain language learning, but calls into question whether they include knowledge of grammatical structure.

Significant improvement of intractable headache after transsphenoidal surgery in patients with pituitary adenomas; preoperative neuroradiological evaluation and intraoperative intrasellar pressure measurement.

PubMed

Hayashi, Yasuhiko; Kita, Daisuke; Iwato, Masayuki; Fukui, Issei; Oishi, Masahiro; Tsutsui, Taishi; Tachibana, Osamu; Nakada, Mitsutoshi

2016-04-01

Headache is the most common symptom of both primary and metastatic brain tumor, and is generally considered the primary symptom in patients with large pituitary adenomas. However, patients with small pituitary adenomas rarely complain of intractable headache, and neurosurgeons are unsure whether such small adenomas actually contribute to headache. If conventional medical treatments for headache prove ineffective, surgical removal of the adenoma can be considered as an alternative management strategy. We conducted a retrospective review of 180 patients who underwent transsphenoidal surgery (TSS) for pituitary adenomas at Kanazawa University Hospital between 2006 and 2014. Patients with acute phase intratumoral hemorrhage were excluded. We identified nine patients with intractable headache as the chief complaint associated with small pituitary adenoma (diameters 15.8 ± 2.6 mm, 11-20 mm), non-functioning in eight, and prolactin-secreting in one. The preoperative neuroradiological studies and headache characteristics were assessed retrospectively, and the intrasellar pressure evaluation was performed during TSS in the last seven patients. All nine patients had complete or substantial resolution of their formerly intractable headache after TSS. Headaches consisted of ocular pain ipsilateral to the adenoma localization within the sella in four cases and bifrontal headache in five. Magnetic resonance imaging of these patients revealed small diaphragmatic foramen, which were so narrow that only the pituitary stalk could pass. Computed tomography scans showed ossification beneath the sellar floor in the sphenoid sinus, presellar type in six cases, and choncal type in three. The adenomas included cysts in seven cases. There was no cavernous sinus invasion. Intrasellar pressure measurements averaged 41.5 ± 8.5 mmHg, range 34-59, significantly higher than in control patients without headache (n = 12), namely 22.2 ± 10.6 mmHg (16-30). In this study, the authors demonstrated the validity of TSS in the treatment of intractable headache associated with pituitary adenoma. The presence of ocular pain, especially ipsilateral to the adenoma, integrity of the diaphragm sella, and ossification in the sphenoid sinus, cyst or hemorrhage and the absence of cavernous sinus invasion were the indications for TSS for patients complaining of intractable headache and having pituitary adenomas.

Variational principle for the Navier-Stokes equations.

PubMed

Kerswell, R R

1999-05-01

A variational principle is presented for the Navier-Stokes equations in the case of a contained boundary-driven, homogeneous, incompressible, viscous fluid. Based upon making the fluid's total viscous dissipation over a given time interval stationary subject to the constraint of the Navier-Stokes equations, the variational problem looks overconstrained and intractable. However, introducing a nonunique velocity decomposition, u(x,t)=phi(x,t) + nu(x,t), "opens up" the variational problem so that what is presumed a single allowable point over the velocity domain u corresponding to the unique solution of the Navier-Stokes equations becomes a surface with a saddle point over the extended domain (phi,nu). Complementary or dual variational problems can then be constructed to estimate this saddle point value strictly from above as part of a minimization process or below via a maximization procedure. One of these reduced variational principles is the natural and ultimate generalization of the upper bounding problem developed by Doering and Constantin. The other corresponds to the ultimate Busse problem which now acts to lower bound the true dissipation. Crucially, these reduced variational problems require only the solution of a series of linear problems to produce bounds even though their unique intersection is conjectured to correspond to a solution of the nonlinear Navier-Stokes equations.

Treatment of intractable chronic cluster headache by occipital nerve stimulation: a cohort of 51 patients.

PubMed

Miller, S; Watkins, L; Matharu, M

2017-02-01

Chronic cluster headache is a rare, highly disabling primary headache condition. When medically intractable, occipital nerve stimulation can offer effective treatment. Open-label series have provided data on small cohorts only. We analyzed 51 subjects to evaluate the long-term outcomes of highly intractable chronic cluster headache with occipital nerve stimulation. Patients with intractable chronic cluster headache were implanted with occipital nerve stimulators during the period 2007-2014. The primary endpoint was improvement in daily attack frequency. Secondary endpoints included attack severity, attack duration, quality-of-life measures, headache disability scores and adverse events. We studied 51 patients [35 males; mean age at implant 47.78 (range 31-70) years; mean follow-up 39.17 (range 2-81) months]. Nineteen patients had other chronic headache types in addition in chronic cluster headache. At final follow-up, there was a 46.1% improvement in attack frequency (P < 0001) across all patients, 49.5% (P < 0.001) in those with cluster headache alone and 40.3% (P = 0.036) in those with multiple phenotypes. There were no significant differences in response in those with or without multiple headache types. The overall response rate (defined as at least a 50% improvement in attack frequency) was 52.9%. Significant reductions were also seen in attack duration and severity. Improvements were noted in headache disability scores and quality-of-life measures. Triptan use of responders dropped by 62.56%, resulting in significant cost savings. Adverse event rates were highly favorable. Occipital nerve stimulation appears to be a safe and efficacious treatment for highly intractable chronic cluster headache even after a mean follow-up of over 3 years. © 2016 EAN.

Long-term outcome and prognostic factors after C2 ganglion decompression in 68 consecutive patients with intractable occipital neuralgia.

PubMed

Choi, Kyu-Sun; Ko, Yong; Kim, Young-Soo; Yi, Hyeong-Joong

2015-01-01

Occipital neuralgia is a rare cause of severe headache characterized by paroxysmal shooting or stabbing pain in the distribution of the greater occipital or lesser occipital nerve. In cases of intractable occipital neuralgia, a definite cause has not been uncovered, so various types of treatment have been applied. The aim of this study is to evaluate the prognostic factors, safety, and long-term clinical efficacy of second cervical (C2) ganglion decompression for intractable occipital neuralgia. Retrospective analysis was performed in 68 patients with medically refractory occipital neuralgia who underwent C2 ganglion decompression. Factors based on patients' demography, pre- and postoperative headache severity/characteristics, medication use, and postoperative complications were investigated. Therapeutic success was defined as pain relief by at least 50 % without ongoing medication. The visual analog scale (VAS) score was significantly reduced between the preoperative and most recent follow-up period. One year later, excellent or good results were achieved in 57 patients (83.9 %), but poor in 11 patients (16.1 %). The long-term outcome after 5 years was only slightly less than the 1-year outcome; 47 of the 68 patients (69.1 %) obtained therapeutic success. Longer duration of headache (over 13 years; p = 0.029) and presence of retro-orbital/frontal radiation (p = 0.040) were significantly associated with poor prognosis. In the current study, C2 ganglion decompression provided durable, adequate pain relief with minimal complications in patients suffering from intractable occipital neuralgia. Due to the minimally invasive and nondestructive nature of this surgical procedure, C2 ganglion decompression is recommended as an initial surgical treatment option for intractable occipital neuralgia before attempting occipital nerve stimulation. However, further study is required to manage the pain recurrence associated with longstanding nerve injury.

Geodynamic Effects of Ocean Tides: Progress and Problems

NASA Technical Reports Server (NTRS)

Richard, Ray

1999-01-01

Satellite altimetry, particularly Topex/Poseidon, has markedly improved our knowledge of global tides, thereby allowing significant progress on some longstanding problems in geodynamics. This paper reviews some of that progress. Emphasis is given to global-scale problems, particularly those falling within the mandate of the new IERS Special Bureau for Tides: angular momentum, gravitational field, geocenter motion. For this discussion I use primarily the new ocean tide solutions GOT99.2, CSR4.0, and TPXO.4 (for which G. Egbert has computed inverse-theoretic error estimates), and I concentrate on new results in angular momentum and gravity and their solid-earth implications. One example is a new estimate of the effective tidal Q at the M_2 frequency, based on combining these ocean models with tidal estimates from satellite laser ranging. Three especially intractable problems are also addressed: (1) determining long-period tides in the Arctic [large unknown effect on the inertia tensor, particularly for Mf]; (2) determining the global psi_l tide [large unknown effect on interpretations of gravimetry for the near-diurnal free wobble]; and (3) determining radiational tides [large unknown temporal variations at important frequencies]. Problems (2) and (3) are related.

Intractable Pruritus After Traumatic Spinal Cord Injury

PubMed Central

Crane, Deborah A; Jaffee, Kenneth M; Kundu, Anjana

2009-01-01

Background: This report describes a young woman with incomplete traumatic cervical spinal cord injury and intractable pruritus involving her dorsal forearm. Method: Case report. Findings: Anatomic distribution of the pruritus corresponded to the dermatomal distribution of her level of spinal cord injury and vertebral fusion. Symptoms were attributed to the spinal cord injury and possible cervical root injury. Pruritus was refractory to all treatments, including topical lidocaine, gabapentin, transcutaneous electrical nerve stimulation, intravenous Bier block, stellate ganglion block, and acupuncture. Conclusions: Further understanding of neuropathic pruritus is needed. Diagnostic workup of intractable pruritus should include advanced imaging to detect ongoing nerve root compression. If diagnostic studies suggest radiculopathy, epidural steroid injection should be considered. Because the autonomic nervous system may be involved in complex chronic pain or pruritic syndromes, sympatholysis via such techniques as stellate ganglion block might be effective. PMID:19777867

Peripheral neurostimulation for control of intractable occipital neuralgia.

PubMed

Weiner, R L; Reed, K L

1999-07-01

Objective. To present a novel approach for treatment of intractable occipital neuralgia using percutaneous peripheral nerve electrostimulation techniques. Methods. Thirteen patients underwent 17 implant procedures for medically refractory occipital neuralgia. A subcutaneous electrode placed transversely at the level of C1 across the base of the occipital nerve trunk produced paresthesias and pain relief covering the regions of occipital nerve pain Results. With follow-up ranging from 1-½ to 6 years, 12 patients continue to report good to excellent response with greater than 50% pain control and requiring little or no additional medications. The 13th patient (first in the series) was subsequently explanted following symptom resolution. Conclusions. In patients with medically intractable occipital neuralgia, peripheral nerve electrostimulation subcutaneously at the level of C1 appears to be a reasonable alternative to more invasive surgical procedures following failure of more conservative therapies.

Growth Failure in Children with Intractable Epilepsy Is Not Due to Increased Resting Energy Expenditure

ERIC Educational Resources Information Center

Bergqvist, A. G. Christina; Trabulsi, Jillian; Schall, Joan I.; Stallings, Virginia A.

2008-01-01

The aim of this study was to evaluate the resting energy expenditure (REE) of children with intractable epilepsy (IE) compared with healthy children, and to determine factors that contribute to the pattern of REE. REE, growth status, and body composition were assessed in 25 prepubertal children with IE (15 males, 10 females; mean age 5y 5mo [SD 2y…

Modified Atkins diet vs classic ketogenic formula in intractable epilepsy.

PubMed

El-Rashidy, O F; Nassar, M F; Abdel-Hamid, I A; Shatla, R H; Abdel-Hamid, M H; Gabr, S S; Mohamed, S G; El-Sayed, W S; Shaaban, S Y

2013-12-01

The study was designed to evaluate the efficacy, safety, and tolerability of the ketogenic diet (KD) whether classic 4:1 formula or the modified Atkins diet (MAD) in intractable childhood epilepsy. Anthropometric measurements and serum lipid profile were measured upon enrollment and after 3 and 6 months in 40 patients with symptomatic intractable epilepsy. Fifteen were given MAD diet, ten were kept on classic 4:1 ketogenic liquid formula, and the rest were allowed to eat as desired. The liquid ketogenic formula group showed significantly higher body mass index compared with those who did not receive KD after 6 months. The lipid profile of KD patients was within normal limits for age and sex during the study period. The rate of change of frequency and severity of seizures showed best improvement in ketogenic liquid formula patients followed by the MAD group than the patients on anti-epileptic medications alone. The KD whether classic 4:1 or MAD is a tolerable, safe, and effective adjuvant therapy for intractable symptomatic childhood epilepsy with limited adverse effects on the growth parameters and accepted changes in the lipid profile. The liquid ketogenic formula patients showed better growth pattern and significantly more seizure control. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Practical Bayesian tomography

NASA Astrophysics Data System (ADS)

Granade, Christopher; Combes, Joshua; Cory, D. G.

2016-03-01

In recent years, Bayesian methods have been proposed as a solution to a wide range of issues in quantum state and process tomography. State-of-the-art Bayesian tomography solutions suffer from three problems: numerical intractability, a lack of informative prior distributions, and an inability to track time-dependent processes. Here, we address all three problems. First, we use modern statistical methods, as pioneered by Huszár and Houlsby (2012 Phys. Rev. A 85 052120) and by Ferrie (2014 New J. Phys. 16 093035), to make Bayesian tomography numerically tractable. Our approach allows for practical computation of Bayesian point and region estimators for quantum states and channels. Second, we propose the first priors on quantum states and channels that allow for including useful experimental insight. Finally, we develop a method that allows tracking of time-dependent states and estimates the drift and diffusion processes affecting a state. We provide source code and animated visual examples for our methods.

Wildfire risk as a socioecological pathology

USGS Publications Warehouse

Fischer, A. Paige; Spies, Thomas A; Steelman, Toddi A; Moseley, Cassandra; Johnson, Bart R.; Bailey, John D.; Ager, Alan A; Bourgeron, Patrick S.; Charnley, Susan; Collins, Brandon M.; Kline, Jeffrey D; Leahy, Jessica E; Littell, Jeremy; Millington, James D. A.; Nielsen-Pincus, Max; Olsen, Christine S; Paveglio, Travis B; Roos, Christopher I.; Steen-Adams, Michelle M; Stevens, Forrest R; Vukomanovic, Jelena; White, Eric M; Bowman, David M J S

2016-01-01

Wildfire risk in temperate forests has become a nearly intractable problem that can be characterized as a socioecological “pathology”: that is, a set of complex and problematic interactions among social and ecological systems across multiple spatial and temporal scales. Assessments of wildfire risk could benefit from recognizing and accounting for these interactions in terms of socioecological systems, also known as coupled natural and human systems (CNHS). We characterize the primary social and ecological dimensions of the wildfire risk pathology, paying particular attention to the governance system around wildfire risk, and suggest strategies to mitigate the pathology through innovative planning approaches, analytical tools, and policies. We caution that even with a clear understanding of the problem and possible solutions, the system by which human actors govern fire-prone forests may evolve incrementally in imperfect ways and can be expected to resist change even as we learn better ways to manage CNHS.

Improved Bat Algorithm Applied to Multilevel Image Thresholding

PubMed Central

2014-01-01

Multilevel image thresholding is a very important image processing technique that is used as a basis for image segmentation and further higher level processing. However, the required computational time for exhaustive search grows exponentially with the number of desired thresholds. Swarm intelligence metaheuristics are well known as successful and efficient optimization methods for intractable problems. In this paper, we adjusted one of the latest swarm intelligence algorithms, the bat algorithm, for the multilevel image thresholding problem. The results of testing on standard benchmark images show that the bat algorithm is comparable with other state-of-the-art algorithms. We improved standard bat algorithm, where our modifications add some elements from the differential evolution and from the artificial bee colony algorithm. Our new proposed improved bat algorithm proved to be better than five other state-of-the-art algorithms, improving quality of results in all cases and significantly improving convergence speed. PMID:25165733

Perspectives on scaling and multiscaling in passive scalar turbulence

NASA Astrophysics Data System (ADS)

Banerjee, Tirthankar; Basu, Abhik

2018-05-01

We revisit the well-known problem of multiscaling in substances passively advected by homogeneous and isotropic turbulent flows or passive scalar turbulence. To that end we propose a two-parameter continuum hydrodynamic model for an advected substance concentration θ , parametrized jointly by y and y ¯, that characterize the spatial scaling behavior of the variances of the advecting stochastic velocity and the stochastic additive driving force, respectively. We analyze it within a one-loop dynamic renormalization group method to calculate the multiscaling exponents of the equal-time structure functions of θ . We show how the interplay between the advective velocity and the additive force may lead to simple scaling or multiscaling. In one limit, our results reduce to the well-known results from the Kraichnan model for passive scalar. Our framework of analysis should be of help for analytical approaches for the still intractable problem of fluid turbulence itself.

Using machine learning to accelerate sampling-based inversion

NASA Astrophysics Data System (ADS)

Valentine, A. P.; Sambridge, M.

2017-12-01

In most cases, a complete solution to a geophysical inverse problem (including robust understanding of the uncertainties associated with the result) requires a sampling-based approach. However, the computational burden is high, and proves intractable for many problems of interest. There is therefore considerable value in developing techniques that can accelerate sampling procedures.The main computational cost lies in evaluation of the forward operator (e.g. calculation of synthetic seismograms) for each candidate model. Modern machine learning techniques-such as Gaussian Processes-offer a route for constructing a computationally-cheap approximation to this calculation, which can replace the accurate solution during sampling. Importantly, the accuracy of the approximation can be refined as inversion proceeds, to ensure high-quality results.In this presentation, we describe and demonstrate this approach-which can be seen as an extension of popular current methods, such as the Neighbourhood Algorithm, and bridges the gap between prior- and posterior-sampling frameworks.

Dual Key Speech Encryption Algorithm Based Underdetermined BSS

PubMed Central

Zhao, Huan; Chen, Zuo; Zhang, Xixiang

2014-01-01

When the number of the mixed signals is less than that of the source signals, the underdetermined blind source separation (BSS) is a significant difficult problem. Due to the fact that the great amount data of speech communications and real-time communication has been required, we utilize the intractability of the underdetermined BSS problem to present a dual key speech encryption method. The original speech is mixed with dual key signals which consist of random key signals (one-time pad) generated by secret seed and chaotic signals generated from chaotic system. In the decryption process, approximate calculation is used to recover the original speech signals. The proposed algorithm for speech signals encryption can resist traditional attacks against the encryption system, and owing to approximate calculation, decryption becomes faster and more accurate. It is demonstrated that the proposed method has high level of security and can recover the original signals quickly and efficiently yet maintaining excellent audio quality. PMID:24955430

Bayesian parameter inference for stochastic biochemical network models using particle Markov chain Monte Carlo

PubMed Central

Golightly, Andrew; Wilkinson, Darren J.

2011-01-01

Computational systems biology is concerned with the development of detailed mechanistic models of biological processes. Such models are often stochastic and analytically intractable, containing uncertain parameters that must be estimated from time course data. In this article, we consider the task of inferring the parameters of a stochastic kinetic model defined as a Markov (jump) process. Inference for the parameters of complex nonlinear multivariate stochastic process models is a challenging problem, but we find here that algorithms based on particle Markov chain Monte Carlo turn out to be a very effective computationally intensive approach to the problem. Approximations to the inferential model based on stochastic differential equations (SDEs) are considered, as well as improvements to the inference scheme that exploit the SDE structure. We apply the methodology to a Lotka–Volterra system and a prokaryotic auto-regulatory network. PMID:23226583

Some Classes of Imperfect Information Finite State-Space Stochastic Games with Finite-Dimensional Solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

McEneaney, William M.

2004-08-15

Stochastic games under imperfect information are typically computationally intractable even in the discrete-time/discrete-state case considered here. We consider a problem where one player has perfect information.A function of a conditional probability distribution is proposed as an information state.In the problem form here, the payoff is only a function of the terminal state of the system,and the initial information state is either linear ora sum of max-plus delta functions.When the initial information state belongs to these classes, its propagation is finite-dimensional.The state feedback value function is also finite-dimensional,and obtained via dynamic programming,but has a nonstandard form due to the necessity ofmore » an expanded state variable.Under a saddle point assumption,Certainty Equivalence is obtained and the proposed function is indeed an information state.« less

Psychiatric consequences of temporal lobectomy for intractable seizures: a 20-30-year follow-up of 14 cases.

PubMed

Stevens, J R

1990-08-01

Between 1958 and 1968, 14 patients from the epilepsy clinic at the University of Oregon Hospitals and Clinics with a diagnosis of temporal lobe epilepsy (TLE) had a temporal lobectomy for medically intractable seizures. Nine of the 14 patients operated on remained seizure-free over the 20-30-year period of follow-up. Between 6 months and one year following temporal lobectomy, two women, previously healthy from a psychiatric standpoint, developed psychoses, and the previous psychiatric problems of four other patients worsened. Two patients, one with incapacitating paranoid personality disorder and the other with explosive rage attacks preoperatively, had marked improvement in their psychiatric status following temporal lobectomy. The remaining six patients, all psychiatrically healthy prior to surgery, have had no change in psychiatric status following surgery. Development of psychosis or deterioration in psychiatric status after surgery was more common in patients with later age of onset, unreality or déjà vu rather than epigastric aura, pre-operative evidence of bilateral brain damage, and persistence of EEG or clinical seizure activity. Development of a chronic psychosis in psychiatrically healthy individuals many months after temporal lobectomy, even when seizures are arrested or ameliorated, suggests that anomalous synaptic regeneration may follow the surgery in these cases. Careful analysis of histories and outcomes may contribute to better understanding of the pathophysiology and anatomical substrates of psychoses.

Palliative Sedation at Home

PubMed Central

Barathi, B

2012-01-01

Patients with advanced cancer often suffer from multiple intractable physical symptoms. Though majority of the symptoms can be controlled, in some of the patients these symptoms remain refractory and uncontrolled till the end. Palliative sedation (PS) is one of the ways to relieve intractable suffering of the dying cancer patients. The main concern while using PS is its life-shortening effect. This case report describes the feasibility of administering PS in Indian home settings. PMID:22837615

Intractability and Mediation of the Nagorno-Karabakh Conflict

DTIC Science & Technology

2013-12-01

belief that “the origins of the current conflict are shrouded in the mists of the twentieth century,” and assert that conflict resolution requires... origin of a dispute as a seed of conflict is not only a poetic metaphor but also a fitting analogy. Some seeds are carefully cultivated while others...than one level with different factors influencing each plane of development. Understanding the origin of an intractable conflict is important but it

The use of ketogenic diet in special situations: expanding use in intractable epilepsy and other neurologic disorders

PubMed Central

2012-01-01

The ketogenic diet has been widely used and proved to be effective for intractable epilepsy. Although the mechanisms underlying its anti-epileptic effects remain to be proven, there are increasing experimental evidences for its neuroprotective effects along with many researches about expanding use of the diet in other neurologic disorders. The first success was reported in glucose transporter type 1 deficiency syndrome, in which the diet served as an alternative metabolic source. Many neurologic disorders share some of the common pathologic mechanisms such as mitochondrial dysfunction, altered neurotransmitter function and synaptic transmission, or abnormal regulation of reactive oxygen species, and the role of the ketogenic diet has been postulated in these mechanisms. In this article, we introduce an overview about the expanding use and emerging trials of the ketogenic diet in various neurologic disorders excluding intractable epilepsy and provide explanations of the mechanisms in that usage. PMID:23049588

Lymphoid irradiation in intractable rheumatoid arthritis. A double-blind, randomized study comparing 750-rad treatment with 2,000-rad treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanly, J.G.; Hassan, J.; Moriarty, M.

1986-01-01

Twenty patients with intractable rheumatoid arthritis were treated with 750-rad or 2,000-rad lymphoid irradiation in a randomized double-blind comparative study. Over a 12-month followup period, there was a significant improvement in 4 of 7 and 6 of 7 standard parameters of disease activity following treatment with 750 rads and 2,000 rads, respectively. Transient, short-term toxicity was less frequent with the lower dose. In both groups, there was a sustained peripheral blood lymphopenia, a selective depletion of T helper (Leu-3a+) lymphocytes, and reduced in vitro mitogen responses. These changes did not occur, however, in synovial fluid. These results suggest that 750-radmore » lymphoid irradiation is as effective as, but less toxic than, that with 2,000 rads in the management of patients with intractable rheumatoid arthritis.« less

An unusual cause of intractable heel pain.

PubMed

Ghani, Samuel; Fazal, Muhammad Ali

2011-01-01

We report a case of severe heel pain that did not respond to noninvasive measures. Magnetic resonance imaging scans revealed a soft tissue mass that after complete surgical excision was found to be an epidermal cyst. The patient experienced full resolution of the symptoms after excision of the epidermal cyst. To our knowledge, intractable heel pain due to an epidermal cyst is rare. We were unable to identify a previous publication describing the presence of an epidermal cyst localized to the heel without a history of previous trauma. From our experience with the present case, we believe that clinicians should consider the possibility of an epidermal inclusion cyst and should have a low threshold for obtaining magnetic resonance imaging scans, in particular, before the initiation of invasive treatment, in the case of intractable heel pain. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Inattentional blindness reflects limitations on perception, not memory: Evidence from repeated failures of awareness.

PubMed

Ward, Emily J; Scholl, Brian J

2015-06-01

Perhaps the most striking phenomenon of visual awareness is inattentional blindness (IB), in which a surprisingly salient event right in front of you may go completely unseen when unattended. Does IB reflect a failure of perception, or only of subsequent memory? Previous work has been unable to answer this question, due to a seemingly intractable dilemma: ruling out memory requires immediate perceptual reports, but soliciting such reports fuels an expectation that eliminates IB. Here we introduce a way of evoking repeated IB in the same subjects and the same session: we show that observers fail to report seeing salient events' not only when they have no expectation, but also when they have the wrong expectations about the events nature. This occurs when observers must immediately report seeing anything unexpected, even mid-event. Repeated IB thus demonstrates that IB is aptly named: it reflects a genuine deficit in moment-by-moment conscious perception, rather than a form of inattentional amnesia.

Successful Treatment of Refractory Seizures With Rufinamide in Children With Schizencephaly: Report of 3 Cases.

PubMed

Verrotti, Alberto; Loiacono, Giulia; Rossi, Alessandra; Tartaro, Armando; Delli Pizzi, Andrea; Coppola, Giangennaro

2015-07-01

Schizencephaly is an uncommon malformation of cortical development. Patients with schizencephaly present with a broad range of severe neurologic symptoms including pharmacoresistant epilepsy. Rufinamide is a new antiepileptic drug approved for use as adjunctive therapy of seizures associated with Lennox-Gastaut syndrome and it is also effective for refractory partial seizures. We report 3 cases of pediatric patients aged 7.2, 8.1, and 10.1 years, respectively, with intractable epilepsy associated with bilateral open-lip schizencephaly and septo-optic dysplasia. The follow-up ranged from 3.8 to 4.1 years. In our patients, the introduction of rufinamide as adjunctive drug led to a dramatic decline in the number of seizures and an improvement in EEG epileptic activity without side effects. Rufinamide seems to be efficacious and safe in patients with epileptic encephalopathies associated with pharmacoresistant epilepsy; further and larger clinical reports and controlled studies could confirm the usefulness of this anticonvulsant drug. © The Author(s) 2014.

Deep Brain Electrical Stimulation in Epilepsy

NASA Astrophysics Data System (ADS)

Rocha, Luisa L.

2008-11-01

The deep brain electrical stimulation has been used for the treatment of neurological disorders such as Parkinson's disease, chronic pain, depression and epilepsy. Studies carried out in human brain indicate that the application of high frequency electrical stimulation (HFS) at 130 Hz in limbic structures of patients with intractable temporal lobe epilepsy abolished clinical seizures and significantly decreased the number of interictal spikes at focus. The anticonvulsant effects of HFS seem to be more effective in patients with less severe epilepsy, an effect associated with a high GABA tissue content and a low rate of cell loss. In addition, experiments using models of epilepsy indicate that HFS (pulses of 60 μs width at 130 Hz at subthreshold current intensity) of specific brain areas avoids the acquisition of generalized seizures and enhances the postictal seizure suppression. HFS is also able to modify the status epilepticus. It is concluded that the effects of HFS may be a good strategy to reduce or avoid the epileptic activity.

Tissue response to aqueous drainage in a functioning Molteno implant.

PubMed Central

Loeffler, K U; Jay, J L

1988-01-01

The tissue reaction to a functioning Molteno implant has been studied by light microscopy and by scanning and transmission electron microscopy. The material was obtained from an aphakic 83-year-old human eye which required enucleation because of intractable bullous keratopathy, despite well controlled intraocular pressure. The tissue response around the silicone rubber tube was that of simple fibroblastic activity. Around the implant, however, there was fibrous tissue in which necrotic cell debris was prominent. No significant inflammation was observed in this tissue, but the choroid beneath the implant showed a focal inflammatory cell infiltrate. The morphology suggests that the tissue around all surfaces of the implant (450 mm2) is exposed to aqueous, which seems to have a toxic effect on the encapsulating connective tissue. The changes seen in the tissue exposed to draining aqueous are similar to those described in experimental studies of the effect of aqueous on cell growth in tissue culture. Images PMID:3342217

Detecting Gunshots Using Wearable Accelerometers

PubMed Central

Loeffler, Charles E.

2014-01-01

Gun violence continues to be a staggering and seemingly intractable issue in many communities. The prevalence of gun violence among the sub-population of individuals under court-ordered community supervision provides an opportunity for intervention using remote monitoring technology. Existing monitoring systems rely heavily on location-based monitoring methods, which have incomplete geographic coverage and do not provide information on illegal firearm use. This paper presents the first results demonstrating the feasibility of using wearable inertial sensors to recognize wrist movements and other signals corresponding to firearm usage. Data were collected from accelerometers worn on the wrists of subjects shooting a number of different firearms, conducting routine daily activities, and participating in activities and tasks that could be potentially confused with firearm discharges. A training sample was used to construct a combined detector and classifier for individual gunshots, which achieved a classification accuracy of 99.4 percent when tested against a hold-out sample of observations. These results suggest the feasibility of using inexpensive wearable sensors to detect firearm discharges. PMID:25184416

Detecting gunshots using wearable accelerometers.

PubMed

Loeffler, Charles E

2014-01-01

Gun violence continues to be a staggering and seemingly intractable issue in many communities. The prevalence of gun violence among the sub-population of individuals under court-ordered community supervision provides an opportunity for intervention using remote monitoring technology. Existing monitoring systems rely heavily on location-based monitoring methods, which have incomplete geographic coverage and do not provide information on illegal firearm use. This paper presents the first results demonstrating the feasibility of using wearable inertial sensors to recognize wrist movements and other signals corresponding to firearm usage. Data were collected from accelerometers worn on the wrists of subjects shooting a number of different firearms, conducting routine daily activities, and participating in activities and tasks that could be potentially confused with firearm discharges. A training sample was used to construct a combined detector and classifier for individual gunshots, which achieved a classification accuracy of 99.4 percent when tested against a hold-out sample of observations. These results suggest the feasibility of using inexpensive wearable sensors to detect firearm discharges.

Adding to the Education Debt: Depressive Symptoms Mediate the Association between Racial Discrimination and Academic Performance in African Americans.

PubMed

English, Devin; Lambert, Sharon F; Ialongo, Nicholas S

2016-08-01

Although the United States faces a seemingly intractable divide between white and African American academic performance, there remains a dearth of longitudinal research investigating factors that work to maintain this gap. The present study examined whether racial discrimination predicted the academic performance of African American students through its effect on depressive symptoms. Participants were a community sample of African American adolescents (N=495) attending urban public schools from grade 7 to grade 9 (Mage=12.5). Structural equation modeling revealed that experienced racial discrimination predicted increases in depressive symptoms 1year later, which, in turn, predicted decreases in academic performance the following year. These results suggest that racial discrimination continues to play a critical role in the academic performance of African American students and, as such, contributes to the maintenance of the race-based academic achievement gap in the United States. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Alzheimer's disease: insights from Drosophila melanogaster models

PubMed Central

Moloney, Aileen; Sattelle, David B.; Lomas, David A.; Crowther, Damian C.

2010-01-01

The power of fruit fly genetics is being deployed against some of the most intractable and economically significant problems in modern medicine, the neurodegenerative diseases. Fly models of Alzheimer's disease can be exposed to the rich diversity of biological techniques that are available to the community and are providing new insights into disease mechanisms, and assisting in the identification of novel targets for therapy. Similar approaches might also help us to interpret the results of genome-wide association studies of human neurodegenerative diseases by allowing us to triage gene “hits” according to whether a candidate risk factor gene has a modifying effect on the disease phenotypes in fly model systems. PMID:20036556

Brain plasticity in the adult: modulation of function in amblyopia with rTMS.

PubMed

Thompson, Benjamin; Mansouri, Behzad; Koski, Lisa; Hess, Robert F

2008-07-22

Amblyopia is a cortically based visual disorder caused by disruption of vision during a critical early developmental period. It is often thought to be a largely intractable problem in adult patients because of a lack of neuronal plasticity after this critical period [1]; however, recent advances have suggested that plasticity is still present in the adult amblyopic visual cortex [2-6]. Here, we present data showing that repetitive transcranial magnetic stimulation (rTMS) of the visual cortex can temporarily improve contrast sensitivity in the amblyopic visual cortex. The results indicate continued plasticity of the amblyopic visual system in adulthood and open the way for a potential new therapeutic approach to the treatment of amblyopia.

On Bayesian Testing of Additive Conjoint Measurement Axioms Using Synthetic Likelihood.

PubMed

Karabatsos, George

2018-06-01

This article introduces a Bayesian method for testing the axioms of additive conjoint measurement. The method is based on an importance sampling algorithm that performs likelihood-free, approximate Bayesian inference using a synthetic likelihood to overcome the analytical intractability of this testing problem. This new method improves upon previous methods because it provides an omnibus test of the entire hierarchy of cancellation axioms, beyond double cancellation. It does so while accounting for the posterior uncertainty that is inherent in the empirical orderings that are implied by these axioms, together. The new method is illustrated through a test of the cancellation axioms on a classic survey data set, and through the analysis of simulated data.

Development of minimally invasive surgery for intractable epilepsy

NASA Astrophysics Data System (ADS)

Yamakawa, Takeshi

2009-04-01

Epilepsy is a chronic brain disorder characterized by recurrent seizures. The seizure is shot down by the surgical removal of the region which is so called "epileptogenc focus". However, the accuracy to detect the focus is not good (order of cm). Thus the extirpation of focus with significant margin causes the removal of normal brain and leads to the severe aftereffects such as restricted vision, motor dysfunction, disorder of memory, and so on. To cope with this problem, we should develop the technology of (1) detecting the epileptogenic focus, and (2) necrotizing the epileptogenic focus excluding normal brain by (a) colliquative necrosis with flash freezing and melting or (b) cauterizing by focused laser beam.

Perfluorocarbon Nanoparticles:. A Theranostic Platform Technology

NASA Astrophysics Data System (ADS)

Lanza, Gregory M.; Winter, Patrick M.; Caruthers, Shelton D.; Hughes, Michael S.; Hu, Grace; Pan, Dipanjan; Schmieder, Anne H.; Pham, Christine; Wickline, Samuel A.

2013-09-01

Nanomedicine clearly offers unique tools to address intractable medical problems in cancer and cardiovascular disease from entirely new perspectives. Among the theranostic options emerging in this new wave of biotechnology development, the perfluorocarbon nanoparticles have shown robust potential in vivo for diagnosing, characterizing, treating and following proliferating cancers, progressive atherosclerosis, rheumatoid arthritis and much more. These molecular imaging agents have been demonstrated for use with ultrasound, MRI, CT, and SPECT/CT. Moreover, the synergism of imaging for confirmation of therapeutic delivery, for dosimetry, and for noninvasively following early treatment responses is discussed. Image-guided drug delivery based on nanotechnology is emerging as a powerful clinical opportunity, and PFC nanoparticles are among the leading technologies reaching clinical testing today with this potential.

Self-calibrating models for dynamic monitoring and diagnosis

NASA Technical Reports Server (NTRS)

Kuipers, Benjamin

1994-01-01

The present goal in qualitative reasoning is to develop methods for automatically building qualitative and semiquantitative models of dynamic systems and to use them for monitoring and fault diagnosis. The qualitative approach to modeling provides a guarantee of coverage while our semiquantitative methods support convergence toward a numerical model as observations are accumulated. We have developed and applied methods for automatic creation of qualitative models, developed two methods for obtaining tractable results on problems that were previously intractable for qualitative simulation, and developed more powerful methods for learning semiquantitative models from observations and deriving semiquantitative predictions from them. With these advances, qualitative reasoning comes significantly closer to realizing its aims as a practical engineering method.

From yellow rain to green wheat: 25 years of trichothecene biosynthesis research.

PubMed

Desjardins, Anne E

2009-06-10

Trichothecene biosynthesis research at the U.S. Department of Agriculture in Peoria, IL, began in 1984 in response to concerns about the use of trichothecenes in biological warfare, but continued as a long-term research program on the intractable problem of trichothecene contamination of human foods and animal feeds. Over 25 years, the trichothecene biosynthesis research group integrated natural product chemistry with fungal genetics and plant pathology in the laboratory and in the field to understand how and why Fusarium species make these complex and highly toxic metabolites. This interdisciplinary research placed trichothecenes in the unique class of fungal metabolites that not only cause mycotoxicoses in animals but also are virulence factors in plant disease.

Global Optimization of N-Maneuver, High-Thrust Trajectories Using Direct Multiple Shooting

NASA Technical Reports Server (NTRS)

Vavrina, Matthew A.; Englander, Jacob A.; Ellison, Donald H.

2016-01-01

The performance of impulsive, gravity-assist trajectories often improves with the inclusion of one or more maneuvers between flybys. However, grid-based scans over the entire design space can become computationally intractable for even one deep-space maneuver, and few global search routines are capable of an arbitrary number of maneuvers. To address this difficulty a trajectory transcription allowing for any number of maneuvers is developed within a multi-objective, global optimization framework for constrained, multiple gravity-assist trajectories. The formulation exploits a robust shooting scheme and analytic derivatives for computational efficiency. The approach is applied to several complex, interplanetary problems, achieving notable performance without a user-supplied initial guess.

C2 Nerve Field Stimulation for the Treatment of Fibromyalgia: A Prospective, Double-blind, Randomized, Controlled Cross-over Study.

PubMed

Plazier, Mark; Ost, Jan; Stassijns, Gaëtane; De Ridder, Dirk; Vanneste, Sven

2015-01-01

Fibromyalgia is a condition characterized by widespread chronic pain. Due to the high prevalence and high costs, it has a substantial burden on society. Treatment results are diverse and only help a small subset of patients. C2 nerve field stimulation, aka occipital nerve stimulation, is helpful and a minimally invasive treatment for primary headache syndromes. Small C2 pilot studies seem to be beneficial in fibromyalgia. Forty patients were implanted with a subcutaneous electrode in the C2 dermatoma as part of a prospective, double-blind, randomized, controlled cross-over study followed by an open label follow up period of 6 months. The patients underwent 2 week periods of different doses of stimulation consisting of minimal (.1 mA), subthreshold, and suprathreshold (for paresthesias) in a randomized order. Twenty seven patients received a permanent implant and 25 completed the 6 month open label follow up period. During the 6 week trial phase of the study, patients had an overall decrease of 36% on the fibromyalgia impact questionnaire (FIQ), a decrease of 33% fibromyalgia pain and improvement of 42% on the impact on daily life activities and quality. These results imply an overall improvement in the disease burden, maintained at 6 months follow up, as well as an improvement in life quality of 50%. Seventy six percent of patients were satisfied or very satisfied with their treatment. There seems to be a dose-response curve, with increasing amplitudes leading to better clinical outcomes. Subcutaneous C2 nerve field stimulation seems to offer a safe and effective treatment option for selected medically intractable patients with fibromyalgia. Copyright © 2015 Elsevier Inc. All rights reserved.

Chronic idiopathic constipation: a psychological enquiry.

PubMed

Dykes, S; Smilgin-Humphreys, S; Bass, C

2001-01-01

Intractable idiopathic constipation in women is often associated with psychosocial problems. To determine the past and current psychological factors associated with slow and normal transit constipation. Twenty-eight consecutive patients referred for biofeedback treatment were interviewed before the procedure. All were women. Transit studies revealed that 12 had slow transit constipation (STC) and 16 had normal transit constipation (NTC). Patients were assessed for evidence of previous and current psychiatric diagnoses using a standardized diagnostic interview schedule. A full family and social history was noted. Self-rating scales were used to measure psychological distress, abnormal attitudes to eating and current psychosocial functioning. The mean age of the 28 patients was 38.2 years (SD = 10.8) with a mean duration of symptoms of 17.5 years (SD = 16.9). Seventeen (61%) had a current psychiatric disorder and 18 (64%) a previous episode of psychiatric illness. The mean age of the 16 NTC patients was 38.4 years (SD = 10.1) with a mean duration of symptoms of 12.4 years (SD = 15.9). By contrast, the 12 STC patients had a much longer mean duration of constipation (24.3 years; SD = 16.4), a mean age of 37.9 years (SD = 12.1), with half having an onset in childhood. The STC patients reported more psychosocial distress on the rating scales than those with NTC, and only one did not experience some form of adverse life event or gynaecological procedure in the 6 months before the onset of constipation. Eleven (39%) of the 28 women had had a hysterectomy at a mean age of 36 years, but only four (14%) reported a history of sexual abuse. Of the nine (32%) patients who reported markedly distorted attitudes to food, six had NTC and three had STC. Of consecutive patients undergoing psychological assessment for intractable constipation, three fifths had evidence of current, and two thirds a previous, affective disorder. One third reported distorted attitudes to food. Although STC is a chronic disorder accompanied by high rates of psychological distress, it does not appear to be associated with gross functional impairment. We suggest that patients who present to surgical departments with chronic intractable constipation should routinely have a psychological assessment.

New research on women's low participation in science and technology

NASA Astrophysics Data System (ADS)

Stout, Jane

It is well known that women have historically been and continue to be grossly underrepresented in technical fields (i.e., the physical sciences, engineering, and computing). This presentation will address the following research questions: What dissuades women from entering into a technical career track, and what are women's experiences like within technical fields? At the same time, this presentation will acknowledge a shortcoming of decades of social science research and interventions designed to improve women's interest and persistence in technical fields: a narrow definition of ``women''. Given that the majority of women in colleges and universities (i.e., the typical sites of social science research) tend to be affluent and/or White, STEM education research that relies on convenience samples at colleges and universities paints a skewed picture of gender issues in technical fields. This presentation will showcase research findings that call into question conventional conceptions of gender disparities in technical fields. Specifically, the presentation will emphasize the importance of recognizing that women constitute more than their gender; women come from a diverse array of backgrounds, which no doubt play a role in the experience of being a woman in technical fields. By understanding the experiences of women from a broad array of demographics groups, the STEM education community can develop a corresponding set of strategies to recruit and retain women with diverse interests, experiences, and values (e.g., first generation versus second college students; women of different racial/ethnic backgrounds). The aim of this presentation is to promote social science research and interventions that acknowledge the nuanced experiences of diverse women in technical fields, in order to address the seemingly intractable problem of women's underrepresentation in technical fields. NSF DUE-1431112, NSF CNS-1246649.

PET MRI Coregistration in Intractable Epilepsy and Gray Matter Heterotopia.

PubMed

Seniaray, Nikhil; Jain, Anuj

2017-03-01

A 25-year-old woman with intractable seizures underwent FDG PET/MRI for seizure focus localization. MRI demonstrated bilateral carpetlike nodular subependymal gray matter and asymmetrical focal dilatation in the right temporal horn. PET/MRI showed increased FDG within subependymal gray matter with significant hypometabolism in right anterior temporal lobe. EEG and ictal semiology confirmed the right temporal seizure origin. This case highlights the importance of identification of gray matter heterotopia on FDG PET/MRI.

Intractable Electrical Storm After Coronary Artery Bypass Grafting Originating in Abnormal Purkinje Fibers.

PubMed

Tokunaga, Chiho; Tsukada, Toru; Sakamoto, Hiroaki; Naruse, Yoshihisa; Yoshida, Kentaro; Sekiguchi, Yukio; Imai, Akito; Aonuma, Kazutaka; Hiramatsu, Yuji

2016-01-01

Electrical storm is a rare but critical complication following revascularization in patients with ischemic heart disease. We report the case of a 67-year-old man who developed drug refractory intractable electrical storm after emergent coronary artery bypass grafting for ischemic cardiomyopathy. The electrical storm was successfully eliminated by percutaneous endocardial radiofrequency catheter ablation targeting the abnormal Purkinje-related triggering ventricular premature contractions in a low-voltage zone. © 2015 Wiley Periodicals, Inc.

The Predictable Failure of Educational Reform: Can We Change Course before It's Too Late? The Jossey-Bass Education Series and the Jossey-Bass Social and Behavioral Science Series.

ERIC Educational Resources Information Center

Sarason, Seymour B.

Schools have been intractable to change and the attainment of goals set by reformers. A major failure has been the inability of reformers to confront this intractability. As a result, each new wave of reform learns nothing from earlier efforts and comes up with recommendations that have failed in the past. Nine chapters explore why reform efforts…

[Clinical efficacy of one-lung ventilation in treatment of children postoperatively intractable atelectasis].

PubMed

Huo, J M; Bai, K; Fu, Y Q; Liu, C J; Xu, F

2017-11-02

Objective: To investigate the effect of fiberoptic bronchoscope-guided one-lung ventilation (OLV) on treatment of intractable atelectasis in children. Method: This retrospective cohort study was conducted in Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University from December 2014 to May 2017. Six patients with intractable atelectasis of left lung were included. Three cases were male and three female with the age from 1.5 to 11.0 years. The endotracheal tube was intubated to the left main bronchus for OLV by the guidance of fiberoptic bronchoscopy. The effect of treatment by monitoring the chest imaging after treatment was evaluated. Result: Six pediatric patients were successfully cured by OLV. The duration of OLV ranged from 1.5 to 30.0 hours, and the intervals of OLV were usually 3 to 5 days. Each patient received 6 to 20 OLV treatments. Chest images showed the left lung reexpanded obviously after OLV treatments. Five patients successfully weaned from invasive ventilation and were discharged. Another patient turned better, discharged from hospital with noninvasive ventilation and weaned from noninvasive ventilation one month later after discharge. During the procedure of OLV, the vital signs of all patients were stable and no complication occurred. Conclusion: OLV with selective bronchial intubation guided by fiber bronchoscope is a safe and effective treatment for intractable atelectasis in children.

Clinical observation of a modified surgical method: posterior vaginal mesh suspension of female rectocele with intractable constipation.

PubMed

Hong, Ling; Li, Huai-Fang; Sun, Jing; Zhu, Jian-Long; Ai, Gui-hai; Li, Li; Zhang, Bo; Chi, Feng-li; Tong, Xiao-Wen

2012-01-01

To explore the feasibility and effectiveness of a modified posterior vaginal mesh suspension method in treating female rectocele with intractable constipation. Descriptive study (Canadian Task Force classification II-3). The study was performed in the Study Center for Female Pelvic Dysfunction Disease, Department of Obstetrics and Gynecology, Tongji Hospital, Tongji University School of Medicine, Shanghai, China. The Study Center includes 15 physicians, most of whom have received advanced training in pelvic floor dysfunctional disease and can skillfully perform many types of operations in patients with such disease. Almost 1500 operations to treat pelvic floor dysfunctional disease are performed every year at the center. Thirty-six women with rectocele with intractable constipation. Posterior vaginal mesh suspension. All patients were followed up for 15 to 36 months. In 29 patients, the condition was cured completely; in 5 patients it had improved; and in 2 patients, the intervention had no effect. Insofar as recovery and improved results, the overall effectiveness rate was 94.4%. Posterior vaginal mesh suspension is an effective, harmless, and convenient method for treatment of female rectocele with intractable constipation. It has positive short-term curative effects, with few complications and sequelae. However, the long-term effects of posterior vaginal mesh suspension should be evaluated. Copyright © 2012 AAGL. Published by Elsevier Inc. All rights reserved.

Unraveling Quantum Annealers using Classical Hardness

PubMed Central

Martin-Mayor, Victor; Hen, Itay

2015-01-01

Recent advances in quantum technology have led to the development and manufacturing of experimental programmable quantum annealing optimizers that contain hundreds of quantum bits. These optimizers, commonly referred to as ‘D-Wave’ chips, promise to solve practical optimization problems potentially faster than conventional ‘classical’ computers. Attempts to quantify the quantum nature of these chips have been met with both excitement and skepticism but have also brought up numerous fundamental questions pertaining to the distinguishability of experimental quantum annealers from their classical thermal counterparts. Inspired by recent results in spin-glass theory that recognize ‘temperature chaos’ as the underlying mechanism responsible for the computational intractability of hard optimization problems, we devise a general method to quantify the performance of quantum annealers on optimization problems suffering from varying degrees of temperature chaos: A superior performance of quantum annealers over classical algorithms on these may allude to the role that quantum effects play in providing speedup. We utilize our method to experimentally study the D-Wave Two chip on different temperature-chaotic problems and find, surprisingly, that its performance scales unfavorably as compared to several analogous classical algorithms. We detect, quantify and discuss several purely classical effects that possibly mask the quantum behavior of the chip. PMID:26483257

ReacKnock: Identifying Reaction Deletion Strategies for Microbial Strain Optimization Based on Genome-Scale Metabolic Network

PubMed Central

Xu, Zixiang; Zheng, Ping; Sun, Jibin; Ma, Yanhe

2013-01-01

Gene knockout has been used as a common strategy to improve microbial strains for producing chemicals. Several algorithms are available to predict the target reactions to be deleted. Most of them apply mixed integer bi-level linear programming (MIBLP) based on metabolic networks, and use duality theory to transform bi-level optimization problem of large-scale MIBLP to single-level programming. However, the validity of the transformation was not proved. Solution of MIBLP depends on the structure of inner problem. If the inner problem is continuous, Karush-Kuhn-Tucker (KKT) method can be used to reformulate the MIBLP to a single-level one. We adopt KKT technique in our algorithm ReacKnock to attack the intractable problem of the solution of MIBLP, demonstrated with the genome-scale metabolic network model of E. coli for producing various chemicals such as succinate, ethanol, threonine and etc. Compared to the previous methods, our algorithm is fast, stable and reliable to find the optimal solutions for all the chemical products tested, and able to provide all the alternative deletion strategies which lead to the same industrial objective. PMID:24348984

Implicit Plasma Kinetic Simulation Using The Jacobian-Free Newton-Krylov Method

NASA Astrophysics Data System (ADS)

Taitano, William; Knoll, Dana; Chacon, Luis

2009-11-01

The use of fully implicit time integration methods in kinetic simulation is still area of algorithmic research. A brute-force approach to simultaneously including the field equations and the particle distribution function would result in an intractable linear algebra problem. A number of algorithms have been put forward which rely on an extrapolation in time. They can be thought of as linearly implicit methods or one-step Newton methods. However, issues related to time accuracy of these methods still remain. We are pursuing a route to implicit plasma kinetic simulation which eliminates extrapolation, eliminates phase-space from the linear algebra problem, and converges the entire nonlinear system within a time step. We accomplish all this using the Jacobian-Free Newton-Krylov algorithm. The original research along these lines considered particle methods to advance the distribution function [1]. In the current research we are advancing the Vlasov equations on a grid. Results will be presented which highlight algorithmic details for single species electrostatic problems and coupled ion-electron electrostatic problems. [4pt] [1] H. J. Kim, L. Chac'on, G. Lapenta, ``Fully implicit particle in cell algorithm,'' 47th Annual Meeting of the Division of Plasma Physics, Oct. 24-28, 2005, Denver, CO

Finding undetected protein associations in cell signaling by belief propagation.

PubMed

Bailly-Bechet, M; Borgs, C; Braunstein, A; Chayes, J; Dagkessamanskaia, A; François, J-M; Zecchina, R

2011-01-11

External information propagates in the cell mainly through signaling cascades and transcriptional activation, allowing it to react to a wide spectrum of environmental changes. High-throughput experiments identify numerous molecular components of such cascades that may, however, interact through unknown partners. Some of them may be detected using data coming from the integration of a protein-protein interaction network and mRNA expression profiles. This inference problem can be mapped onto the problem of finding appropriate optimal connected subgraphs of a network defined by these datasets. The optimization procedure turns out to be computationally intractable in general. Here we present a new distributed algorithm for this task, inspired from statistical physics, and apply this scheme to alpha factor and drug perturbations data in yeast. We identify the role of the COS8 protein, a member of a gene family of previously unknown function, and validate the results by genetic experiments. The algorithm we present is specially suited for very large datasets, can run in parallel, and can be adapted to other problems in systems biology. On renowned benchmarks it outperforms other algorithms in the field.

Influencing Busy People in a Social Network

PubMed Central

Sarkar, Kaushik; Sundaram, Hari

2016-01-01

We identify influential early adopters in a social network, where individuals are resource constrained, to maximize the spread of multiple, costly behaviors. A solution to this problem is especially important for viral marketing. The problem of maximizing influence in a social network is challenging since it is computationally intractable. We make three contributions. First, we propose a new model of collective behavior that incorporates individual intent, knowledge of neighbors actions and resource constraints. Second, we show that the multiple behavior influence maximization is NP-hard. Furthermore, we show that the problem is submodular, implying the existence of a greedy solution that approximates the optimal solution to within a constant. However, since the greedy algorithm is expensive for large networks, we propose efficient heuristics to identify the influential individuals, including heuristics to assign behaviors to the different early adopters. We test our approach on synthetic and real-world topologies with excellent results. We evaluate the effectiveness under three metrics: unique number of participants, total number of active behaviors and network resource utilization. Our heuristics produce 15-51% increase in expected resource utilization over the naïve approach. PMID:27711127

Scientific strategy and ad hoc response: the problem of typhoid in America and England, C. 1910-50.

PubMed

Hardy, Anne

2014-01-01

In the early twentieth century, death rates from typhoid in European cities reached an all time low. By contrast, death rates in America were six times as high, and the American public health community began a crusade against the disease in 1912. In the 1920s, hopes for greater control of the disease focused not just on sewers and drinking water supplies, but on the newly established scientific means of immunization, the supervision of food-related pathways of infection, and the management of healthy carriers. The management of carriers, which lay at the core of any typhoid control program, proved an intractable problem, and typhoid remained a public health concern. America and England both struggled with control of the disease during the interwar period. Coming from different starting points, however, their approaches to the problem differed. This paper compares and contrasts these different public health strategies, considers the variable quality of support provided by bacteriological laboratories, and demonstrates that "accidental" typhoid outbreaks continued to happen up to the outbreak of World War II.

A variational approach to moment-closure approximations for the kinetics of biomolecular reaction networks

NASA Astrophysics Data System (ADS)

Bronstein, Leo; Koeppl, Heinz

2018-01-01

Approximate solutions of the chemical master equation and the chemical Fokker-Planck equation are an important tool in the analysis of biomolecular reaction networks. Previous studies have highlighted a number of problems with the moment-closure approach used to obtain such approximations, calling it an ad hoc method. In this article, we give a new variational derivation of moment-closure equations which provides us with an intuitive understanding of their properties and failure modes and allows us to correct some of these problems. We use mixtures of product-Poisson distributions to obtain a flexible parametric family which solves the commonly observed problem of divergences at low system sizes. We also extend the recently introduced entropic matching approach to arbitrary ansatz distributions and Markov processes, demonstrating that it is a special case of variational moment closure. This provides us with a particularly principled approximation method. Finally, we extend the above approaches to cover the approximation of multi-time joint distributions, resulting in a viable alternative to process-level approximations which are often intractable.

Quantum Machine Learning

NASA Technical Reports Server (NTRS)

Biswas, Rupak

2018-01-01

Quantum computing promises an unprecedented ability to solve intractable problems by harnessing quantum mechanical effects such as tunneling, superposition, and entanglement. The Quantum Artificial Intelligence Laboratory (QuAIL) at NASA Ames Research Center is the space agency's primary facility for conducting research and development in quantum information sciences. QuAIL conducts fundamental research in quantum physics but also explores how best to exploit and apply this disruptive technology to enable NASA missions in aeronautics, Earth and space sciences, and space exploration. At the same time, machine learning has become a major focus in computer science and captured the imagination of the public as a panacea to myriad big data problems. In this talk, we will discuss how classical machine learning can take advantage of quantum computing to significantly improve its effectiveness. Although we illustrate this concept on a quantum annealer, other quantum platforms could be used as well. If explored fully and implemented efficiently, quantum machine learning could greatly accelerate a wide range of tasks leading to new technologies and discoveries that will significantly change the way we solve real-world problems.

Influencing Busy People in a Social Network.

PubMed

Sarkar, Kaushik; Sundaram, Hari

2016-01-01

We identify influential early adopters in a social network, where individuals are resource constrained, to maximize the spread of multiple, costly behaviors. A solution to this problem is especially important for viral marketing. The problem of maximizing influence in a social network is challenging since it is computationally intractable. We make three contributions. First, we propose a new model of collective behavior that incorporates individual intent, knowledge of neighbors actions and resource constraints. Second, we show that the multiple behavior influence maximization is NP-hard. Furthermore, we show that the problem is submodular, implying the existence of a greedy solution that approximates the optimal solution to within a constant. However, since the greedy algorithm is expensive for large networks, we propose efficient heuristics to identify the influential individuals, including heuristics to assign behaviors to the different early adopters. We test our approach on synthetic and real-world topologies with excellent results. We evaluate the effectiveness under three metrics: unique number of participants, total number of active behaviors and network resource utilization. Our heuristics produce 15-51% increase in expected resource utilization over the naïve approach.

Attention and material-specific memory in children with lateralized epilepsy.

PubMed

Engle, Jennifer A; Smith, Mary Lou

2010-01-01

Epilepsy is frequently associated with attention and memory problems. In adults, lateralization of seizure focus impacts the type of memory affected (left-sided lesions primarily impact verbal memory, while right-sided lesions primarily impact visual memory), but the relationship between seizure focus and the nature of the memory impairment is less clear in children. The current study examines the correlation between parent-reported attention problems and material-specific memory (verbal or visual-spatial) in 65 children (ages 6-16) with medically intractable lateralized epilepsy. There were no significant differences in attention and memory between those with left-lateralized epilepsy (n=25) and those with right-lateralized epilepsy (n=40). However, in the left-lateralized group attention problems were significantly negatively correlated only with delayed visual memory (r=-.450, p<.05), while the right-lateralized group demonstrated the opposite pattern (attention problems significantly negatively correlated with delayed verbal memory; r=-.331, p<.05). These findings suggest that lateralization of seizure focus may in fact impact children's memory in a material-specific manner, while problems with attention may impact memory more globally. Therefore, interventions designed to improve attention in children with epilepsy may have utility in improving certain aspects of memory, but further suggest that in children with lateralized epilepsy, material-specific memory deficits may not resolve with such interventions.

Neonatal severe intractable diarrhoea as the presenting manifestation of an unclassified congenital disorder of glycosylation (CDG-x)

PubMed Central

Mention, K; Michaud, L; Dobbelaere, D; Guimber, D; Gottrand, F; Turck, D

2001-01-01

A case of severe and protracted diarrhoea is reported, which started in the neonatal period and progressively associated with neurological impairment, dysmorphy, hepatosplenomegaly, and hepatic insufficiency, from which the patient died at 2 years of age. Isoelectric focusing of serum transferrin showed a congenital disorder of glycosylation type I pattern but the basic defect could not be identified. This observation shows that congenital disorder of glycosylation is a cause of intractable diarrhoea in neonates.

 PMID:11668168

Extreme-Scale Bayesian Inference for Uncertainty Quantification of Complex Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biros, George

Uncertainty quantification (UQ)—that is, quantifying uncertainties in complex mathematical models and their large-scale computational implementations—is widely viewed as one of the outstanding challenges facing the field of CS&E over the coming decade. The EUREKA project set to address the most difficult class of UQ problems: those for which both the underlying PDE model as well as the uncertain parameters are of extreme scale. In the project we worked on these extreme-scale challenges in the following four areas: 1. Scalable parallel algorithms for sampling and characterizing the posterior distribution that exploit the structure of the underlying PDEs and parameter-to-observable map. Thesemore » include structure-exploiting versions of the randomized maximum likelihood method, which aims to overcome the intractability of employing conventional MCMC methods for solving extreme-scale Bayesian inversion problems by appealing to and adapting ideas from large-scale PDE-constrained optimization, which have been very successful at exploring high-dimensional spaces. 2. Scalable parallel algorithms for construction of prior and likelihood functions based on learning methods and non-parametric density estimation. Constructing problem-specific priors remains a critical challenge in Bayesian inference, and more so in high dimensions. Another challenge is construction of likelihood functions that capture unmodeled couplings between observations and parameters. We will create parallel algorithms for non-parametric density estimation using high dimensional N-body methods and combine them with supervised learning techniques for the construction of priors and likelihood functions. 3. Bayesian inadequacy models, which augment physics models with stochastic models that represent their imperfections. The success of the Bayesian inference framework depends on the ability to represent the uncertainty due to imperfections of the mathematical model of the phenomena of interest. This is a central challenge in UQ, especially for large-scale models. We propose to develop the mathematical tools to address these challenges in the context of extreme-scale problems. 4. Parallel scalable algorithms for Bayesian optimal experimental design (OED). Bayesian inversion yields quantified uncertainties in the model parameters, which can be propagated forward through the model to yield uncertainty in outputs of interest. This opens the way for designing new experiments to reduce the uncertainties in the model parameters and model predictions. Such experimental design problems have been intractable for large-scale problems using conventional methods; we will create OED algorithms that exploit the structure of the PDE model and the parameter-to-output map to overcome these challenges. Parallel algorithms for these four problems were created, analyzed, prototyped, implemented, tuned, and scaled up for leading-edge supercomputers, including UT-Austin’s own 10 petaflops Stampede system, ANL’s Mira system, and ORNL’s Titan system. While our focus is on fundamental mathematical/computational methods and algorithms, we will assess our methods on model problems derived from several DOE mission applications, including multiscale mechanics and ice sheet dynamics.« less

Novel use of narrow paddle electrodes for occipital nerve stimulation--technical note.

PubMed

Abhinav, Kumar; Park, Nicholas D; Prakash, Savithru K; Love-Jones, Sarah; Patel, Nikunj K

2013-01-01

Occipital nerve stimulation (ONS), an established treatment for medically intractable headache syndromes, has lead migration rates quoted up to 24%. In a series of patients with ideal characteristics for this treatment modality, we describe an operative technique for ONS involving the novel use of narrow paddle electrodes: "S8 Lamitrode" (St. Jude Medical [SJM], St. Paul, MN, USA). Five patients (occipital neuralgia [ON] = 4; chronic migraine [CM] = 1) were treated with ONS between 2010 and 2011. All patients had a successful trial of peripheral neurostimulation (Algotec Ltd, Crawley, UK) therapy. Operative technique involved the use of a park-bench position, allowing simultaneous exposure of the occipital and infraclavicular regions. Through a retromastoid/occipital incision just beneath the external occipital protruberance, exposing the extrafascial plane, the S8 Lamitrode is implanted to intersect both greater occipital nerves for bilateral pain or unilateral greater and lesser occipital nerves for unilateral ON or with significant component of the pain relating to the lesser occipital nerve. Over the median follow-up of 12 months, there were no episodes of lead migration or revision. There also was significant improvement in symptoms in all patients. This is the first reported use of S8 Lamitrode electrode for ONS. This narrow electrode is suited for this role leading to minimal trauma during surgical placement, facilitates resolution of problems with lead migration, and optimizes effect with stimulation focused more in direction of the occipital nerves without skin involvement. To date, the SJM Genesis neurostimulation system, with percutaneous electrodes only, is CE mark approved in Europe for peripheral nerve stimulation of the occipital nerves for the management of pain and disability for patients diagnosed with intractable CM. Further developments and studies are required for better devices to suit ONS, thereby avoiding frequently encountered problems and which may clarify the role of paddle leads in ONS. © 2012 International Neuromodulation Society.

Transforming Conflict into Effective Action: A Case Study on the Effects of Anthropogenic Sound on Marine Mammals

NASA Astrophysics Data System (ADS)

Lewandowski, Jill K.

Like many wicked environmental problems of our time, marine sound and its potential effects on marine mammals is characterized by high levels of scientific uncertainty, diversified values across many stakeholder groups, political and regulatory complexities, and a continually evolving ecological and social environment. Further, the history of conflict and the relationships between major actors has rooted the issue firmly in identity conflict where prejudices lead to avoidance of working together. What results is continuing controversy, failed management decisions, litigation and an increasing frustration by all parties on why a better solution cannot be found. Ultimately, the intractability of the issue is not about the science, nor will the science ever tame the issue on its own. Rather, the issue is intractable because of the conflict between people about the most appropriate path forward. It is then imperative to understand, address, and transform this conflict in order to move off the decision carousel toward improved conservation outcomes and sustainable decisions for all. This research used an explanatory case study approach to quantitatively and qualitatively investigate the context and reasoning underlying conflict on this issue. Three methods were used in order to triangulate the data, and thus add rigor, including: (1) a document review of 230 publications: (2) exploratory interviews with 10 collaborative action experts and semi-structured interviews with 58 marine mammals and sound stakeholders; and (3) participant review of selected analyses. Data elucidate how different stakeholder groups define the problem and potential solutions, how they see their role and view the role of other stakeholders, specific experiences that increased or decrease conflict, and design preferences for a collaborative effort. These data are combined with conflict transformation principles to provide recommendations for a collaborative, transformative framework designed to help build capacity for groups to work together and ultimately tame this wicked issue.

The standard of care and conflicts at the end of life in critical care: lessons from medical-legal crossroads and the role of a quasi-judicial tribunal in decision-making.

PubMed

Hawryluck, Laura; Sibbald, Robert; Chidwick, Paula

2013-12-01

The goals of this qualitative study were to review the last 7 years of end of life legal decisions within the critical care field to explore how medical benefit is defined and by whom and the role of the standard of care (SoC) in conflict resolution. A public online, non-profit database of the Federation of Law Societies of Canada was searched for relevant Consent and Capacity Board decisions from 2003 to 2012. In total, 1486 cases were collected, and purposive sampling identified a total of 29 decisions regarding use of life-sustaining treatments at end of life. Using modified grounded theory, decisions were read and analyzed from a central SoC concept to understand definitions of benefit, rationales for case adjudication, and repercussions of legal recourse in conflict resolution. Medical benefit was clearly defined, and its role in determining SoC, transparent. Perceptions of variability in SoC were enhanced by physicians in intractable conflicts seeking legal validation by framing SoC issues as "best interest" determinations. The results reveal some key problems in recourse to the Consent and Capacity Board for clinicians, patients and substitute decision makers in such conflict situations. This study can help improve decision-making by debunking myth of variability in determinations of medical benefit and the standards of care at end of life and reveal the pitfalls of legal recourse in resolving intractable conflicts. © 2013.

Young Children in Intractable Conflicts: The Israeli Case.

PubMed

Nasie, Meytal; Diamond, Aurel Harrison; Bar-Tal, Daniel

2015-10-08

The article examines the political socialization of young Jewish-Israeli children who live under the Israeli-Palestinian intractable conflict. It proposes arguments and presents empirical evidence to suggest that the way in which political socialization of young children happens in this context contributes to the development of conflict-supporting narratives of ethos of conflict and collective memory by the youngest generation. As a result, the conflict solidifies adherence to these narratives in adulthood, thereby serving as a major obstacle to the processes of peace-making and peace-building. Specifically, as evidence for showing how the political socialization works in Israel, a series of studies conducted in Israeli kindergartens and elementary schools are presented. These studies recount the contents acquired by young children, as well as contents delivered by teachers, related to the Israeli-Palestinian conflict. This indicates the serious consequences of acquiring conflict-supporting narratives at an early age in societies involved in intractable conflict. © 2015 by the Society for Personality and Social Psychology, Inc.

Bayesian inference of physiologically meaningful parameters from body sway measurements.

PubMed

Tietäväinen, A; Gutmann, M U; Keski-Vakkuri, E; Corander, J; Hæggström, E

2017-06-19

The control of the human body sway by the central nervous system, muscles, and conscious brain is of interest since body sway carries information about the physiological status of a person. Several models have been proposed to describe body sway in an upright standing position, however, due to the statistical intractability of the more realistic models, no formal parameter inference has previously been conducted and the expressive power of such models for real human subjects remains unknown. Using the latest advances in Bayesian statistical inference for intractable models, we fitted a nonlinear control model to posturographic measurements, and we showed that it can accurately predict the sway characteristics of both simulated and real subjects. Our method provides a full statistical characterization of the uncertainty related to all model parameters as quantified by posterior probability density functions, which is useful for comparisons across subjects and test settings. The ability to infer intractable control models from sensor data opens new possibilities for monitoring and predicting body status in health applications.

Neonatal hypoglycemia: A wide range of electroclinical manifestations and seizure outcomes.

PubMed

Arhan, Ebru; Öztürk, Zeynep; Serdaroğlu, Ayşe; Aydın, Kürşad; Hirfanoğlu, Tuğba; Akbaş, Yılmaz

2017-09-01

We examined the various types of epilepsy in children with neonatal hypoglycemia in order to define electroclinical and prognostic features of these patients. We retrospectively reviewed the medical records of patients with a history of symptomatic neonatal hypoglycaemia who have been followed at Gazi University Hospital Pediatric Neurology Department between 2006 and 2015. Patients with perinatal asphyxia were excluded. Details of each patient's perinatal history, neurological outcome, epilepsy details, seizure outcome and EEG and brain MRI findings were reviewed. Fourty five patients (range 6 mo-15 y) with a history of symptomatic neonatal hypoglycaemia were included the study. Epilepsy developed in 36 patients and 23 of them had intractable epilepsy. All patients had occipital brain injury. We observed that most of the patients, either manifesting focal or generalized seizures, further develop intractable epilepsy. This finding establishes neonatal hypoglycemia as a possible cause to be considered in any case of intractable epilepsy. Copyright © 2017 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Chronic herpes simplex type-1 encephalitis with intractable epilepsy in an immunosuppressed patient.

PubMed

Laohathai, Christopher; Weber, Daniel J; Hayat, Ghazala; Thomas, Florian P

2016-02-01

Chronic herpes simplex virus type-1 encephalitis (HSE-1) is uncommon. Past reports focused on its association with prior documented acute infection. Here, we describe a patient with increasingly intractable epilepsy from chronic HSE-1 reactivation without history of acute central nervous system infection. A 49-year-old liver transplant patient with 4-year history of epilepsy after initiation of cyclosporine developed increasingly frequent seizures over 3 months. Serial brain magnetic resonance imaging showed left temporoparietal cortical edema that gradually improved despite clinical decline. Herpes simplex virus type-1 (HSV-1) DNA was detected in cerebrospinal fluid by polymerase chain reaction. Cerebrospinal fluid HSV-1&2 IgM was negative. Seizures were controlled after acyclovir treatment, and the patient remained seizure free at 1-year follow-up. Chronic HSE is a cause of intractable epilepsy, can occur without a recognized preceding acute phase, and the clinical course of infection may not directly correlate with neuroimaging changes.

Efficacy of and patient compliance with a ketogenic diet in adults with intractable epilepsy: a meta-analysis.

PubMed

Ye, Fang; Li, Xiao-Jia; Jiang, Wan-Lin; Sun, Hong-Bin; Liu, Jie

2015-01-01

Despite the successful use of a ketogenic diet in pediatric epilepsy, its application in adults has been limited. The aim of this meta-analysis was to summarize the findings of relevant published studies in order to identify the efficacy of and compliance with a ketogenic diet and its main subtypes (i.e., classic ketogenic diet and modified Atkins diet) in adults with intractable epilepsy, and to provide useful information for clinical practice. Electronic searches of PubMed, EMBASE, Google Scholar, and the ISI Web of Science were conducted to identify studies of the efficacy of and patient compliance with a ketogenic diet in adults with intractable epilepsy; the included studies were reviewed. Meta-analyses were performed using STATA to determine combined efficacy rates and combined rates of compliance with the ketogenic diet and its main subtypes. In total, 12 studies qualified for inclusion, and data from 270 patients were evaluated.The results of the meta-analysis revealed combined efficacy rates of all types of ketogenic diet, a classical ketogenic diet, and a modified Atkins diet were 42%, 52%, and 34%, respectively; the corresponding combined compliance rates were 45%, 38%, and 56%. The results indicate that a ketogenic diet is a promising complementary therapy in adult intractable epilepsy, and that while a classical ketogenic diet may be more effective, adult patients are likely to be less compliant with it than with a modified Atkins diet.

Mutation screening of the CDKL5 gene in cryptogenic infantile intractable epilepsy and review of clinical sensitivity.

PubMed

Intusoma, Utcharee; Hayeeduereh, Fadell; Plong-On, Oradawan; Sripo, Thanya; Vasiknanonte, Punnee; Janjindamai, Supachai; Lusawat, Apasri; Thammongkol, Sasipa; Visudtibhan, Anannit; Limprasert, Pornprot

2011-09-01

To perform CDKL5 mutation screening in Thai children with cryptogenic infantile intractable epilepsy and to determine the clinical sensitivity of CDKL5 screening when different inclusion criteria were applied. Children with cryptogenic infantile intractable epilepsy were screened for CDKL5 mutation using multiplex ligation-dependent probe amplification and DNA sequencing. The clinical sensitivity was reviewed by combining the results of studies using similar inclusion screening criteria. Thirty children (19 girls and 11 boys) with a median seizure onset of 7 months were screened. Almost a half had infantile spasms and one fifth had stereotypic hand movements. A novel c.2854C>T (p.R952X) was identified in an ambulatory girl who had severe mental retardation, multiple types of seizures without Rett-like features. Her mother had a mild intellectual disability, yet her grandmother and half sister were normal despite having the same genetic alteration (random X-inactivation patterns). The pathogenicity of p.R952X identified here was uncertain since healthy relatives and 6 female controls also harbor this alteration. The clinical sensitivity of CDKL5 mutation screening among females with Rett-like features and negative MECP2 screening was 7.8% while the clinical sensitivity among females having cryptogenic intractable seizures with an onset before the ages of 12, 6 and 3 months were 4.7, 11.6 and 14.3%, respectively. Copyright © 2011 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Xp22.3 genomic deletions involving the CDKL5 gene in girls with early onset epileptic encephalopathy.

PubMed

Mei, Davide; Marini, Carla; Novara, Francesca; Bernardina, Bernardo D; Granata, Tiziana; Fontana, Elena; Parrini, Elena; Ferrari, Anna R; Murgia, Alessandra; Zuffardi, Orsetta; Guerrini, Renzo

2010-04-01

Mutations of the X-linked gene cyclin-dependent kinase-like 5 (CDKL5) cause an X-linked encephalopathy with early onset intractable epilepsy, including infantile spasms and other seizure types, and a Rett syndrome (RTT)-like phenotype. Very limited information is available on the frequency and phenotypic spectrum associated with CDKL5 deletions/duplications. We investigated the role of CDKL5 deletions/duplications in causing early onset intractable epilepsy of unknown etiology in girls. We studied 49 girls with early onset intractable epilepsy, with or without infantile spasms, and developmental impairment, for whom no etiologic factors were obvious after clinical examination, brain magnetic resonance imaging (MRI) and expanded screening for inborn errors of metabolism. We performed CDKL5 gene mutation analysis in all and multiplex ligation dependent probe amplification assay (MLPA) in those who were mutation negative. Custom Array-comparative genomic hybridization (CGH), breakpoint polymerase chain reaction (PCR) analysis, and X-inactivation studies were performed in patients in whom MLPA uncovered a genomic alteration. We found CDKL5 mutations in 8.2% (4 of 49) of patients and genomic deletions in 8.2% (4 of 49). Overall, abnormalities of the CDKL5 gene accounted for 16.3% (8 of 49) of patients. CDKL5 gene deletions are an under-ascertained cause of early onset intractable epilepsy in girls. Genetic testing of CDKL5, including both mutation and deletion/duplication analysis, should be considered in this clinical subgroup.

Early experience with activated recombinant factor VII for intractable hemorrhage after cardiovascular surgery.

PubMed

Halkos, Michael E; Levy, Jerrold H; Chen, Edward; Reddy, V Seenu; Lattouf, Omar M; Guyton, Robert A; Song, Howard K

2005-04-01

Intractable hemorrhage after complex cardiovascular operations is a serious and potentially lethal complication. We report our experience with the use of activated recombinant factor VIIa (rFVIIa) as rescue therapy for patients with refractory postoperative hemorrhage. From April 2002 through December 2003, 9 patients received rFVIIa for intractable hemorrhage after cardiovascular surgery. Patients underwent aortic surgery (2), coronary artery bypass graft surgery (4), double valve operations (2), and mitral valve replacement (1). Four of these procedures were reoperations. Intraoperative aprotinin was used in all patients. All patients underwent standard heparinization (300 IU/kg) before cardiopulmonary bypass and reversal with protamine. Five patients underwent reexploration for mediastinal hemorrhage before treatment; 2 were reexplored twice. The average transfusion requirement before rFVIIa administration was 9 U of blood, 7 U of plasma, 22 U of platelets, and 19 U of cryoprecipitate. rFVIIa was administered as an intravenous bolus at 68 to 120 mug/kg. Mean time of administration from the first operation was 10.9 +/- 7.2 hours. At the time of activated rFVIIa administration, chest tube drainage averaged 640 mL/h. In all patients, chest tube drainage was dramatically reduced to less than 100 mL/h within 5 hours after drug delivery. None of the patients required reexploration after treatment. There were no postoperative neurologic or cardiovascular complications. When used as rescue therapy for intractable hemorrhage after cardiovascular surgery, rFVIIa may be effective in promoting hemostasis, preventing reexploration, and reducing transfusion requirements.

Familial partial trisomy 15q11-13 presenting as intractable epilepsy in the child and schizophrenia in the mother.

PubMed

Michelson, Marina; Eden, Avi; Vinkler, Chana; Leshinsky-Silver, Esther; Kremer, Uri; Lerman-Sagie, Tally; Lev, Dorit

2011-05-01

Various rearrangements involve the proximal long arm of chromosome 15, including deletions, duplications, translocations, inversions and supernumerary marker chromosome of an inverted duplication. The large marker 15, that contains the Prader-Willi syndrome (PWS)/Angelman syndrome (AS) chromosome region, is usually associated with an abnormal phenotype of moderate to severe mental retardation, seizures, poor motor coordination, early-onset central hypotonia, autism and autistic-like behavior, schizophrenia and mild dysmorphic features. We report a ten year-old girl with normal intelligence prior to the onset of seizures, who developed severe intractable epilepsy at the age of seven years. Family history was significant for a mother with recurrent episodes of acute psychosis. The patient's and mother's karyotype revealed 47,XX+m. Array comparative genomic hybridization (A-CGH) identified a gain of 13 BAC clones from 15q11.2 through 15q13.1, which was then confirmed by FISH to be part of the marker chromosome. This duplicated region contains the SNRPN/UBE3A locus. This case demonstrates that a duplication of 15q11-13 can present differently in the same family either as intractable epilepsy or as a psychiatric illness and that intelligence can be preserved. We suggest that CGH microarray should be performed in cases with intractable epilepsy or schizophrenia, with or without mental retardation. Copyright © 2010 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Cannabis and intractable chronic pain: an explorative retrospective analysis of Italian cohort of 614 patients

PubMed Central

Fanelli, Guido; De Carolis, Giuliano; Leonardi, Claudio; Longobardi, Adele; Sarli, Ennio; Allegri, Massimo; Schatman, Michael E

2017-01-01

Background Despite growing interest in the therapeutic use of cannabis to manage chronic pain, only limited data that address these issues are available. In recent years, a number of nations have introduced specific laws to allow patients to use cannabis preparations to treat a variety of medical conditions. In 2015, the Italian government authorized the use of cannabis to treat several diseases, including chronic pain generally, spasticity in multiple sclerosis, cachexia and anorexia among AIDS and cancer patients, glaucoma, Tourette syndrome, and certain types of epilepsy. We present the first snapshot of the Italian experience with cannabis use for chronic pain over the initial year of its use. Methods This is a retrospective case series analysis of all chronic pain patients treated with oral or vaporized cannabis in six hubs during the initial year following the approval of the new Italian law (December 2015 to November 2016). We evaluated routes of administration, types of cannabis products utilized, dosing, and effectiveness and safety of the treatment. Results As only one of the six centers has extensively used cannabinoids for intractable chronic pain (614 patients of 659), only the population from Azienda Ospedaliero Universitaria Pisana (Pisa) was considered. Cannabis tea was the primary mode of delivery, and in almost all cases, it was used in association with all the other pain treatments. Initial and follow-up cannabinoid concentrations were found to vary considerably. At initial follow-up, 76.2% of patients continued the treatment, and <15% stopped the treatment due to side effects (none of which were severe). Conclusion We present the first analysis of Italian clinical practice of the use of cannabinoids for a large variety of chronic pain syndromes. From this initial snapshot, we determined that the treatment seems to be effective and safe, although more data and subsequent trials are needed to better investigate its ideal clinical indication. PMID:28579820

Cannabis and intractable chronic pain: an explorative retrospective analysis of Italian cohort of 614 patients.

PubMed

Fanelli, Guido; De Carolis, Giuliano; Leonardi, Claudio; Longobardi, Adele; Sarli, Ennio; Allegri, Massimo; Schatman, Michael E

2017-01-01

Despite growing interest in the therapeutic use of cannabis to manage chronic pain, only limited data that address these issues are available. In recent years, a number of nations have introduced specific laws to allow patients to use cannabis preparations to treat a variety of medical conditions. In 2015, the Italian government authorized the use of cannabis to treat several diseases, including chronic pain generally, spasticity in multiple sclerosis, cachexia and anorexia among AIDS and cancer patients, glaucoma, Tourette syndrome, and certain types of epilepsy. We present the first snapshot of the Italian experience with cannabis use for chronic pain over the initial year of its use. This is a retrospective case series analysis of all chronic pain patients treated with oral or vaporized cannabis in six hubs during the initial year following the approval of the new Italian law (December 2015 to November 2016). We evaluated routes of administration, types of cannabis products utilized, dosing, and effectiveness and safety of the treatment. As only one of the six centers has extensively used cannabinoids for intractable chronic pain (614 patients of 659), only the population from Azienda Ospedaliero Universitaria Pisana (Pisa) was considered. Cannabis tea was the primary mode of delivery, and in almost all cases, it was used in association with all the other pain treatments. Initial and follow-up cannabinoid concentrations were found to vary considerably. At initial follow-up, 76.2% of patients continued the treatment, and <15% stopped the treatment due to side effects (none of which were severe). We present the first analysis of Italian clinical practice of the use of cannabinoids for a large variety of chronic pain syndromes. From this initial snapshot, we determined that the treatment seems to be effective and safe, although more data and subsequent trials are needed to better investigate its ideal clinical indication.

Surgical management of bacterial meningitis.

PubMed Central

Humphreys, R. P.

1975-01-01

A variety of associated lesions may require the neurosurgeon's assistance in the management of bacterial meningitis. As treatment of this infection of the central nervous system proceeds, the surgeon will have to decide about the concurrent or subsequent operative treatment of congenital dysraphic states, paraneural infections, compound fractures or penetrating wounds of thecranium or spine, or infected bypass shunts for cerebrospinal fluid (CSF). In patients with intractable meningitic infections the surgeon may have to insert a ventricular drainage-irrigation system to permit adequate perfusion of the CSF pathways with antibiotic. Hydrocephalus or subdural effusions complicating meningitis may bring the patient to the surgeon long after the infection has been cured. This paper examines these problems and outlines the current principles of management. Images FIG. 1 FIG. 2 PMID:1098760

Resilient campuses: leveraging resources among small- and moderate-sized institutions of higher education.

PubMed

Green, Rebekah

2014-01-01

Universities and colleges provide students with an opportunity to grow personally and professionally through a structured series of learning experiences. Yet disasters can interrupt traditional place-based education and prove to be intractable policy problems. The challenges of developing robust plans and drilling them extensively are most pronounced among smaller public colleges and universities. This article describes how three small- to moderate-sized higher education institutions formed a consortium to better prepare for emergencies, despite limited resources. Together the institutions built common templates, hired joint staff, and created a suit of joint exercises appropriate for their small size and campus-specific needs. In the process, they shared unique perspectives that improved resilience across the institutions.

Time-Bin-Encoded Boson Sampling with a Single-Photon Device.

PubMed

He, Yu; Ding, X; Su, Z-E; Huang, H-L; Qin, J; Wang, C; Unsleber, S; Chen, C; Wang, H; He, Y-M; Wang, X-L; Zhang, W-J; Chen, S-J; Schneider, C; Kamp, M; You, L-X; Wang, Z; Höfling, S; Lu, Chao-Yang; Pan, Jian-Wei

2017-05-12

Boson sampling is a problem strongly believed to be intractable for classical computers, but can be naturally solved on a specialized photonic quantum simulator. Here, we implement the first time-bin-encoded boson sampling using a highly indistinguishable (∼94%) single-photon source based on a single quantum-dot-micropillar device. The protocol requires only one single-photon source, two detectors, and a loop-based interferometer for an arbitrary number of photons. The single-photon pulse train is time-bin encoded and deterministically injected into an electrically programmable multimode network. The observed three- and four-photon boson sampling rates are 18.8 and 0.2 Hz, respectively, which are more than 100 times faster than previous experiments based on parametric down-conversion.

Is It Time for Synthetic Biodiversity Conservation?

PubMed

Piaggio, Antoinette J; Segelbacher, Gernot; Seddon, Philip J; Alphey, Luke; Bennett, Elizabeth L; Carlson, Robert H; Friedman, Robert M; Kanavy, Dona; Phelan, Ryan; Redford, Kent H; Rosales, Marina; Slobodian, Lydia; Wheeler, Keith

2017-02-01

Evidence indicates that, despite some critical successes, current conservation approaches are not slowing the overall rate of biodiversity loss. The field of synthetic biology, which is capable of altering natural genomes with extremely precise editing, might offer the potential to resolve some intractable conservation problems (e.g., invasive species or pathogens). However, it is our opinion that there has been insufficient engagement by the conservation community with practitioners of synthetic biology. We contend that rapid, large-scale engagement of these two communities is urgently needed to avoid unintended and deleterious ecological consequences. To this point we describe case studies where synthetic biology is currently being applied to conservation, and we highlight the benefits to conservation biologists from engaging with this emerging technology. Published by Elsevier Ltd.

Theory of mind in dogs?: examining method and concept.

PubMed

Horowitz, Alexandra

2011-12-01

In line with other research, Udell, Dorey, and Wynne's (in press) finding that dogs and wolves pass on some trials of a putative theory-of-mind test and fail on others is as informative about the methods and concepts of the research as about the subjects. This commentary expands on these points. The intertrial differences in the target article demonstrate how critical the choice of cues is in experimental design; the intersubject-group differences demonstrate how life histories can interact with experimental design. Even the best-designed theory-of-mind tests have intractable logical problems. Finally, these and previous research results call for the introduction of an intermediate stage of ability, a rudimentary theory of mind, to describe subjects' performance.

Addressing controversies in science education: a pragmatic approach to evolution education

NASA Astrophysics Data System (ADS)

Hildebrand, David; Bilica, Kimberly; Capps, John

2008-09-01

Science education controversies typically prove more intractable than those in scientific research because they involve a wider range of considerations (e.g., epistemic, social, ethical, political, and religious). How can educators acknowledge central issues in a controversy (such as evolution)? How can such problems be addressed in a way that is ethically sensitive and intellectually responsible? Drawing in part on pragmatic philosopher John Dewey, our solution is politically proactive, philosophically pragmatic, and grounded in research. Central to our proposal is (1) steps toward creating a philosophical “total attitude” that is democratic, imaginative, and hypothetical; (2) a deeper understanding of how scientific theories can be pragmatically true; and (3) an assessment of differing pedagogical approaches for teaching evolution in the classroom.

On the Parameterized Complexity of Some Optimization Problems Related to Multiple-Interval Graphs

NASA Astrophysics Data System (ADS)

Jiang, Minghui

We show that for any constant t ≥ 2, K -Independent Set and K-Dominating Set in t-track interval graphs are W[1]-hard. This settles an open question recently raised by Fellows, Hermelin, Rosamond, and Vialette. We also give an FPT algorithm for K-Clique in t-interval graphs, parameterized by both k and t, with running time max { t O(k), 2 O(klogk) } ·poly(n), where n is the number of vertices in the graph. This slightly improves the previous FPT algorithm by Fellows, Hermelin, Rosamond, and Vialette. Finally, we use the W[1]-hardness of K-Independent Set in t-track interval graphs to obtain the first parameterized intractability result for a recent bioinformatics problem called Maximal Strip Recovery (MSR). We show that MSR-d is W[1]-hard for any constant d ≥ 4 when the parameter is either the total length of the strips, or the total number of adjacencies in the strips, or the number of strips in the optimal solution.

Learning planar Ising models

DOE PAGES

Johnson, Jason K.; Oyen, Diane Adele; Chertkov, Michael; ...

2016-12-01

Inference and learning of graphical models are both well-studied problems in statistics and machine learning that have found many applications in science and engineering. However, exact inference is intractable in general graphical models, which suggests the problem of seeking the best approximation to a collection of random variables within some tractable family of graphical models. In this paper, we focus on the class of planar Ising models, for which exact inference is tractable using techniques of statistical physics. Based on these techniques and recent methods for planarity testing and planar embedding, we propose a greedy algorithm for learning the bestmore » planar Ising model to approximate an arbitrary collection of binary random variables (possibly from sample data). Given the set of all pairwise correlations among variables, we select a planar graph and optimal planar Ising model defined on this graph to best approximate that set of correlations. Finally, we demonstrate our method in simulations and for two applications: modeling senate voting records and identifying geo-chemical depth trends from Mars rover data.« less

Learning planar Ising models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Jason K.; Oyen, Diane Adele; Chertkov, Michael

Inference and learning of graphical models are both well-studied problems in statistics and machine learning that have found many applications in science and engineering. However, exact inference is intractable in general graphical models, which suggests the problem of seeking the best approximation to a collection of random variables within some tractable family of graphical models. In this paper, we focus on the class of planar Ising models, for which exact inference is tractable using techniques of statistical physics. Based on these techniques and recent methods for planarity testing and planar embedding, we propose a greedy algorithm for learning the bestmore » planar Ising model to approximate an arbitrary collection of binary random variables (possibly from sample data). Given the set of all pairwise correlations among variables, we select a planar graph and optimal planar Ising model defined on this graph to best approximate that set of correlations. Finally, we demonstrate our method in simulations and for two applications: modeling senate voting records and identifying geo-chemical depth trends from Mars rover data.« less

Trapping of diffusing particles by striped cylindrical surfaces. Boundary homogenization approach

PubMed Central

Dagdug, Leonardo; Berezhkovskii, Alexander M.; Skvortsov, Alexei T.

2015-01-01

We study trapping of diffusing particles by a cylindrical surface formed by rolling a flat surface, containing alternating absorbing and reflecting stripes, into a tube. For an arbitrary stripe orientation with respect to the tube axis, this problem is intractable analytically because it requires dealing with non-uniform boundary conditions. To bypass this difficulty, we use a boundary homogenization approach which replaces non-uniform boundary conditions on the tube wall by an effective uniform partially absorbing boundary condition with properly chosen effective trapping rate. We demonstrate that the exact solution for the effective trapping rate, known for a flat, striped surface, works very well when this surface is rolled into a cylindrical tube. This is shown for both internal and external problems, where the particles diffuse inside and outside the striped tube, at three orientations of the stripe direction with respect to the tube axis: (a) perpendicular to the axis, (b) parallel to the axis, and (c) at the angle of π/4 to the axis. PMID:26093574

Is criminal violence a non-communicable disease? Exploring the epidemiology of violence in Jamaica.

PubMed

McDavid, H A; Cowell, N; McDonald, A

2011-07-01

There is a high level of criminal violence that afflicts the Jamaican society. While it is certainly noncommunicable in the context of medicine and public health, the concepts of social contagion and the well-established fact of the intergenerational transfer of effects of trauma raise questions as to whether or not it is non-communicable in a social sense. Historically, scholars have linked Jamaican criminal violence to three main roots: poverty and urban decay, political patronage, garrisonisation and more recently to a fourth, the growth in transnational organized crime (TOC). Traditionally as well, policymakers have brought the three discrete perspectives of criminology, criminal justice and public health to bear on the problem. This paper applies a conceptual framework derived from a combination of epidemiology and the behavioural sciences to argue that a sustainable resolution to this looming and intractable social problem must take the form of a cocktail of policies that encompasses all three approaches at levels ranging from the community to the international.

Intractable Seizures and Rehabilitation in Ciguatera Poisoning.

PubMed

Derian, Armen; Khurana, Seema; Rothenberg, Joshua; Plumlee, Charles

2017-05-01

Ciguatera fish poisoning is the most frequently reported seafood toxin illness associated with the ingestion of contaminated tropical fish. Diagnosis relies on a history of recent tropical fish ingestion and subsequent development of gastrointestinal, cardiovascular, and neurological symptoms. Ciguatera poisoning usually has a self-limited time course, and its management involves symptomatic control and supportive care. This case report presents an uncommon case of ciguatera poisoning with prolonged intractable seizures refractory to standard antiseizure medications. The patient also had significant functional decline that responded to rigorous inpatient rehabilitation not previously described in literature.

Engineering and commercialization of human-device interfaces, from bone to brain.

PubMed

Knothe Tate, Melissa L; Detamore, Michael; Capadona, Jeffrey R; Woolley, Andrew; Knothe, Ulf

2016-07-01

Cutting edge developments in engineering of tissues, implants and devices allow for guidance and control of specific physiological structure-function relationships. Yet the engineering of functionally appropriate human-device interfaces represents an intractable challenge in the field. This leading opinion review outlines a set of current approaches as well as hurdles to design of interfaces that modulate transfer of information, i.a. forces, electrical potentials, chemical gradients and haptotactic paths, between endogenous and engineered body parts or tissues. The compendium is designed to bridge across currently separated disciplines by highlighting specific commonalities between seemingly disparate systems, e.g. musculoskeletal and nervous systems. We focus on specific examples from our own laboratories, demonstrating that the seemingly disparate musculoskeletal and nervous systems share common paradigms which can be harnessed to inspire innovative interface design solutions. Functional barrier interfaces that control molecular and biophysical traffic between tissue compartments of joints are addressed in an example of the knee. Furthermore, we describe the engineering of gradients for interfaces between endogenous and engineered tissues as well as between electrodes that physically and electrochemically couple the nervous and musculoskeletal systems. Finally, to promote translation of newly developed technologies into products, protocols, and treatments that benefit the patients who need them most, regulatory and technical challenges and opportunities are addressed on hand from an example of an implant cum delivery device that can be used to heal soft and hard tissues, from brain to bone. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

A socio-ecological adaptive approach to contaminated mega-site management: from 'control and correct' to 'coping with change'.

PubMed

Schirmer, Mario; Lyon, Ken; Armstrong, James E; Farrell, Katharine N

2012-01-01

Mega-sites have a notable impact on surrounding ecological systems. At such sites there are substantial risks associated with complex socio-ecological interactions that are hard to characterize, let alone model and predict. While the urge to control and clean-up mega-sites (control and correct) is understandable, rather than setting a goal of cleaning up such sites, we suggest a more realistic response strategy is to address these massive and persistent sources of contamination by acknowledging their position as new features of the socio-ecological landscapes within which they are located. As it seems nearly impossible to clean up such sites, we argue for consideration of a 'coping with change' rather than a 'control and correct' approach. This strategy recognizes that the current management option for a mega-site, in light of its physical complexities and due to changing societal preferences, geochemical transformations, hydrogeology knowledge and remedial technology options may not remain optimal in future, and therefore needs to be continuously adapted, as community, ecology, technology and understanding change over time. This approach creates an opportunity to consider the relationship between a mega-site and its human and ecological environments in a different and more dynamic way. Our proposed approach relies on iterative adaptive management to incorporate mega-site management into the overall socio-ecological systems of the site's context. This approach effectively embeds mega-site management planning in a triple bottom line and environmental sustainability structure, rather than simply using single measures of success, such as contaminant-based guidelines. Recognizing that there is probably no best solution for managing a mega-site, we present a starting point for engaging constructively with this seemingly intractable issue. Therefore, we aim to initiate discussion about a new approach to mega-site management, in which the complexity of the problems posed by mega-sites is reflected upon in its entirety. These complexities are associated with uncertainties and unknowns that have to be addressed, as they have an impact on the strategies being developed and applied. We contend that the best that can be hoped for in mega-site management is an acceptable solution for the current state of affairs, with good flexibility to modify strategies as new site conditions, remediation possibilities, community preferences and management objectives develop over time. Copyright © 2011 Elsevier B.V. All rights reserved.

A Formative Evaluation of CU-SeeMe.

DTIC Science & Technology

1995-02-01

CU- SeeMe is a video conferencing software package that was designed and programmed at Cornell University. The program works with the TCP/IP network...protocol and allows two or more parties to conduct a real-time video conference with full audio support. In this paper we evaluate CU- SeeMe through...caused the problem and why This helps in the process of formulating solutions for observed usability problems. All the testing results are combined in the Appendix in an illustrated partial redesign of the CU- SeeMe Interface.

Work-Related Stress and Coping Strategies of Professional Women.

ERIC Educational Resources Information Center

Long, Bonita C.

1988-01-01

Interviewed 20 professional women on their work-related stress and coping processes to identify those who were good and poor at coping. Found that more effective copers seemed to have used problem-focused coping such as seeking information or advice or taking problem-solving action, whereas less effective copers seemed to have used strategies such…

Factors Contributing to the Problem of Student Absenteeism in a Rural School

ERIC Educational Resources Information Center

Durborow, Angela

2017-01-01

Student attendance would seem to be a vital link in measuring student success in school. If students are not in school, they miss instruction from the teacher. Without instruction it seems incredibly difficult to complete the work needed to pass classes and be successful in school. The research explored the problem of practice of student…

Fuzzy multiobjective models for optimal operation of a hydropower system

NASA Astrophysics Data System (ADS)

Teegavarapu, Ramesh S. V.; Ferreira, André R.; Simonovic, Slobodan P.

2013-06-01

Optimal operation models for a hydropower system using new fuzzy multiobjective mathematical programming models are developed and evaluated in this study. The models use (i) mixed integer nonlinear programming (MINLP) with binary variables and (ii) integrate a new turbine unit commitment formulation along with water quality constraints used for evaluation of reservoir downstream impairment. Reardon method used in solution of genetic algorithm optimization problems forms the basis for development of a new fuzzy multiobjective hydropower system optimization model with creation of Reardon type fuzzy membership functions. The models are applied to a real-life hydropower reservoir system in Brazil. Genetic Algorithms (GAs) are used to (i) solve the optimization formulations to avoid computational intractability and combinatorial problems associated with binary variables in unit commitment, (ii) efficiently address Reardon method formulations, and (iii) deal with local optimal solutions obtained from the use of traditional gradient-based solvers. Decision maker's preferences are incorporated within fuzzy mathematical programming formulations to obtain compromise operating rules for a multiobjective reservoir operation problem dominated by conflicting goals of energy production, water quality and conservation releases. Results provide insight into compromise operation rules obtained using the new Reardon fuzzy multiobjective optimization framework and confirm its applicability to a variety of multiobjective water resources problems.

Principles of Dataset Versioning: Exploring the Recreation/Storage Tradeoff

PubMed Central

Bhattacherjee, Souvik; Chavan, Amit; Huang, Silu; Deshpande, Amol; Parameswaran, Aditya

2015-01-01

The relative ease of collaborative data science and analysis has led to a proliferation of many thousands or millions of versions of the same datasets in many scientific and commercial domains, acquired or constructed at various stages of data analysis across many users, and often over long periods of time. Managing, storing, and recreating these dataset versions is a non-trivial task. The fundamental challenge here is the storage-recreation trade-off: the more storage we use, the faster it is to recreate or retrieve versions, while the less storage we use, the slower it is to recreate or retrieve versions. Despite the fundamental nature of this problem, there has been a surprisingly little amount of work on it. In this paper, we study this trade-off in a principled manner: we formulate six problems under various settings, trading off these quantities in various ways, demonstrate that most of the problems are intractable, and propose a suite of inexpensive heuristics drawing from techniques in delay-constrained scheduling, and spanning tree literature, to solve these problems. We have built a prototype version management system, that aims to serve as a foundation to our DataHub system for facilitating collaborative data science. We demonstrate, via extensive experiments, that our proposed heuristics provide efficient solutions in practical dataset versioning scenarios. PMID:28752014

Fast, Nonlinear, Fully Probabilistic Inversion of Large Geophysical Problems

NASA Astrophysics Data System (ADS)

Curtis, A.; Shahraeeni, M.; Trampert, J.; Meier, U.; Cho, G.

2010-12-01

Almost all Geophysical inverse problems are in reality nonlinear. Fully nonlinear inversion including non-approximated physics, and solving for probability distribution functions (pdf’s) that describe the solution uncertainty, generally requires sampling-based Monte-Carlo style methods that are computationally intractable in most large problems. In order to solve such problems, physical relationships are usually linearized leading to efficiently-solved, (possibly iterated) linear inverse problems. However, it is well known that linearization can lead to erroneous solutions, and in particular to overly optimistic uncertainty estimates. What is needed across many Geophysical disciplines is a method to invert large inverse problems (or potentially tens of thousands of small inverse problems) fully probabilistically and without linearization. This talk shows how very large nonlinear inverse problems can be solved fully probabilistically and incorporating any available prior information using mixture density networks (driven by neural network banks), provided the problem can be decomposed into many small inverse problems. In this talk I will explain the methodology, compare multi-dimensional pdf inversion results to full Monte Carlo solutions, and illustrate the method with two applications: first, inverting surface wave group and phase velocities for a fully-probabilistic global tomography model of the Earth’s crust and mantle, and second inverting industrial 3D seismic data for petrophysical properties throughout and around a subsurface hydrocarbon reservoir. The latter problem is typically decomposed into 104 to 105 individual inverse problems, each solved fully probabilistically and without linearization. The results in both cases are sufficiently close to the Monte Carlo solution to exhibit realistic uncertainty, multimodality and bias. This provides far greater confidence in the results, and in decisions made on their basis.

Therapeutic approach to mite-induced intractable dermatitis using novel immunomodulator FTY720 ointment (fingolimod) in NC/Nga mice.

PubMed

Tsuji, Takumi; Okuno, Satoshi; Kuroda, Ayano; Hamazaki, Junya; Chikami, Takuma; Sakurai, Sakura; Yoshida, Yuya; Banno, Rie; Fujita, Tetsuro; Kohno, Takeyuki

2016-04-01

The increasing incidence and prevalence of atopic dermatitis (AD) demands new therapeutic approaches for treating the disease. We investigated the therapeutic efficacy of immunomodulator FTY720 ointment (fingolimod) for mite-induced intractable AD using an NC/Nga mouse model. Female NC/Nga mice that developed severe AD were divided into four groups: (1) FTY720 (0.001% FTY720 ointment), (2) tacrolimus (tacrolimus hydrate ointment) (3) betamethasone (betamethasone ointment), and (4) ointment base (hydrophilic petrolatum), all of which received treatment six times per week. Therapeutic efficacy after two weeks was evaluated in terms of AD severity, histochemical observations (epidermal hypertrophy, mast cell accumulation, and CD3(+) T cell infiltration), transepidermal water loss (TEWL), and epidermal barrier function (filaggrin expression). Betamethasone treatment showed little effect, confirming that the AD was intractable. In the FTY720 group, AD improved significantly compared with the ointment base group, as did epidermal hypertrophy, mast cell accumulation, and CD3(+) T cell infiltration. In contrast, AD in the tacrolimus and betamethasone groups did not improve significantly, nor did epidermal hypertrophy or mast cell accumulation. Furthermore, in the FTY720 group, TEWL decreased significantly compared with the ointment base group, and filaggrin expression significantly increased compared with the betamethasone and ointment base groups. FTY720 ointment is a promising candidate for treatment of intractable AD. These findings also provide the first evidence that FTY720 ointment ameliorates epidermal barrier function. Copyright © 2015 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Postoperative seizure freedom does not normalize altered connectivity in temporal lobe epilepsy.

PubMed

Maccotta, Luigi; Lopez, Mayra A; Adeyemo, Babatunde; Ances, Beau M; Day, Brian K; Eisenman, Lawrence N; Dowling, Joshua L; Leuthardt, Eric C; Schlaggar, Bradley L; Hogan, Robert Edward

2017-11-01

Specific changes in the functional connectivity of brain networks occur in patients with epilepsy. Yet whether such changes reflect a stable disease effect or one that is a function of active seizure burden remains unclear. Here, we longitudinally assessed the connectivity of canonical cognitive functional networks in patients with intractable temporal lobe epilepsy (TLE), both before and after patients underwent epilepsy surgery and achieved seizure freedom. Seventeen patients with intractable TLE who underwent epilepsy surgery with Engel class I outcome and 17 matched healthy controls took part in the study. The functional connectivity of a set of cognitive functional networks derived from typical cognitive tasks was assessed in patients, preoperatively and postoperatively, as well as in controls, using stringent methods of artifact reduction. Preoperatively, functional networks in TLE patients differed significantly from healthy controls, with differences that largely, but not exclusively, involved the default mode and temporal/auditory subnetworks. However, undergoing epilepsy surgery and achieving seizure freedom did not lead to significant changes in network connectivity, with postoperative functional network abnormalities closely mirroring the preoperative state. This result argues for a stable chronic effect of the disease on brain connectivity, with changes that are largely "burned in" by the time a patient with intractable TLE undergoes epilepsy surgery, which typically occurs years after the initial diagnosis. The result has potential implications for the treatment of intractable epilepsy, suggesting that delaying surgical intervention that may achieve seizure freedom may lead to functional network changes that are no longer reversible by the time of epilepsy surgery. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

Unique and shared areas of cognitive function in children with intractable frontal or temporal lobe epilepsy.

PubMed

Law, Nicole; Widjaja, Elysa; Smith, Mary Lou

2018-03-01

Previous findings have been mixed in terms of identifying a distinct pattern of neuropsychological deficits in children with frontal lobe epilepsy (FLE) and in those with temporal lobe epilepsy (TLE). The current study investigated the neuropsychological similarities and differences across these two pediatric medically intractable localization-related epilepsies. Thirty-eight children with FLE, 20 children with TLE, and 40 healthy children (HC) participated in this study. A comprehensive battery of standardized tests assessed five neuropsychological domains including intelligence, language, memory, executive function, and motor function. A principal component analysis (PCA) was used to distill our neuropsychological measures into latent components to compare between groups. Principal component analysis extracted 5 latent components: executive function (F1), verbal semantics (F2), motor (F3), nonverbal cognition/impulsivity (F4), and verbal cognition/attention (F5). The group with FLE differed from the HC group on F1, F2, F4, and F5, and had worse performance than the group with TLE on F1; the group with TLE had lower performance relative to the HC group on F2. Our findings suggest that, in comparison with neurotypically developing children, children with medically intractable FLE have more widespread neuropsychological impairments than do children with TLE. The differences between the two patient groups were greatest for the factor score most clearly related to executive function. The results provide mixed support for the concept of specificity in neuropsychological dysfunction among different subtypes of localization-related medically intractable childhood epilepsies. Copyright © 2018 Elsevier Inc. All rights reserved.

Hepatic parenchymal atrophy induction for intractable segmental bile duct injury after liver resection.

PubMed

Hwang, Shin; Park, Gil-Chun; Ha, Tae-Yong; Ko, Gi-Young; Gwon, Dong-Il; Choi, Young-Il; Song, Gi-Won; Lee, Sung-Gyu

2012-05-01

Liver resection can result in various types of bile duct injuries but their treatment is usually difficult and often leads to intractable clinical course. We present an unusual case of hepatic segment III duct (B3) injury, which occurred after left medial sectionectomy for large hepatocellular carcinoma and was incidentally detected 1 week later due to bile leak. Since the pattern of this B3 injury was not adequate for operative biliary reconstruction, atrophy induction of the involved hepatic parenchyma was attempted. This treatment consisted of embolization of the segment III portal branch to inhibit bile production, induction of heavy adhesion at the bile leak site and clamping of the percutaneous transhepatic biliary drainage (PTBD) tube to accelerate segment III atrophy. This entire procedure, from liver resection to PTBD tube removal took 4 months. This patient has shown no other complication or tumor recurrence for 4 years to date. These findings suggest that percutaneous segmental portal vein embolization, followed by intentional clamping of external biliary drainage, can effectively control intractable bile leak from segmental bile duct injury.

[Factors for the onset of and the exacerbation of tuberculosis. 4. Clinical factors related to the onset and exacerbation of tuberculosis. b. Middle-aged and elderly patients].

PubMed

Nakagawa, M

1999-10-01

Exacerbating factors of tuberculosis were evaluated from the viewpoint of intractability of the disease including the effectiveness of chemotherapy by comparing patients with intractable tuberculosis and those with nonintractable tuberculosis. Of the patients aged 30 years or above admitted to our hospital for the initial episode of tuberculosis, 42 patients with intractable tuberculosis and 247 controls were compared. No difference was observed between the two groups in life-style factors such as smoking, drinking, and living alone or complications such as diabetes mellitus and cerebrospinal diseases. In the refractory group, a poor general condition with fever and body weight losses on admission, massive discharge of tubercle bacillus, and delayed diagnosis and treatment were frequently observed. Also, patients with a lymphocyte count of 500/mm3 or less such as those with anemia, hypoproteinemia/hypoalbuminemia, high LDH and CRP levels, and a low cholinesterase level were significantly more frequent, and resistant bacteria were detected more frequently in this group.

Intractable Ménière's disease. Modelling of the treatment by means of statistical analysis.

PubMed

Sanchez-Ferrandiz, Noelia; Fernandez-Gonzalez, Secundino; Guillen-Grima, Francisco; Perez-Fernandez, Nicolas

2010-08-01

To evaluate the value of different variables of the clinical history, auditory and vestibular tests and handicap measurements to define intractable or disabling Ménière's disease. This is a prospective study with 212 patients of which 155 were treated with intratympanic gentamicin and considered to be suffering a medically intractable Ménière's disease. Age and sex adjustments were performed with the 11 variables selected. Discriminant analysis was performed either using the aforementioned variables or following the stepwise method. Different variables needed to be sex and/or age adjusted and both data were included in the discriminant function. Two different mathematical formulas were obtained and four models were analyzed. With the model selected, diagnostic accuracy is 77.7%, sensitivity is 94.9% and specificity is 52.8%. After discriminant analysis we found that the most informative variables were the number of vertigo spells, the speech discrimination score, the time constant of the VOR and a measure of handicap, the "dizziness index". Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Innovative Use of the Law to Address Complex Global Health Problems Comment on "The Legal Strength of International Health Instruments - What It Brings toGlobal Health Governance?"

PubMed

Walls, Helen L; Ooms, Gorik

2017-05-20

Addressing the increasingly globalised determinants of many important problems affecting human health is a complex task requiring collective action. We suggest that part of the solution to addressing intractable global health issues indeed lies with the role of new legal instruments in the form of globally binding treaties, as described in the recent article of Nikogosian and Kickbusch. However, in addition to the use of international law to develop new treaties, another part of the solution may lie in innovative use of existing legal instruments. A 2015 court ruling in The Hague, which ordered the Dutch government to cut greenhouse gas emissions by at least 25% within five years, complements this perspective, suggesting a way forward for addressing global health problems that critically involves civil society and innovative use of existing domestic legal instruments. © 2017 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Evolutionary inference via the Poisson Indel Process.

PubMed

Bouchard-Côté, Alexandre; Jordan, Michael I

2013-01-22

We address the problem of the joint statistical inference of phylogenetic trees and multiple sequence alignments from unaligned molecular sequences. This problem is generally formulated in terms of string-valued evolutionary processes along the branches of a phylogenetic tree. The classic evolutionary process, the TKF91 model [Thorne JL, Kishino H, Felsenstein J (1991) J Mol Evol 33(2):114-124] is a continuous-time Markov chain model composed of insertion, deletion, and substitution events. Unfortunately, this model gives rise to an intractable computational problem: The computation of the marginal likelihood under the TKF91 model is exponential in the number of taxa. In this work, we present a stochastic process, the Poisson Indel Process (PIP), in which the complexity of this computation is reduced to linear. The Poisson Indel Process is closely related to the TKF91 model, differing only in its treatment of insertions, but it has a global characterization as a Poisson process on the phylogeny. Standard results for Poisson processes allow key computations to be decoupled, which yields the favorable computational profile of inference under the PIP model. We present illustrative experiments in which Bayesian inference under the PIP model is compared with separate inference of phylogenies and alignments.

Evolutionary inference via the Poisson Indel Process

PubMed Central

Bouchard-Côté, Alexandre; Jordan, Michael I.

2013-01-01

We address the problem of the joint statistical inference of phylogenetic trees and multiple sequence alignments from unaligned molecular sequences. This problem is generally formulated in terms of string-valued evolutionary processes along the branches of a phylogenetic tree. The classic evolutionary process, the TKF91 model [Thorne JL, Kishino H, Felsenstein J (1991) J Mol Evol 33(2):114–124] is a continuous-time Markov chain model composed of insertion, deletion, and substitution events. Unfortunately, this model gives rise to an intractable computational problem: The computation of the marginal likelihood under the TKF91 model is exponential in the number of taxa. In this work, we present a stochastic process, the Poisson Indel Process (PIP), in which the complexity of this computation is reduced to linear. The Poisson Indel Process is closely related to the TKF91 model, differing only in its treatment of insertions, but it has a global characterization as a Poisson process on the phylogeny. Standard results for Poisson processes allow key computations to be decoupled, which yields the favorable computational profile of inference under the PIP model. We present illustrative experiments in which Bayesian inference under the PIP model is compared with separate inference of phylogenies and alignments. PMID:23275296

Quantum Metropolis sampling.

PubMed

Temme, K; Osborne, T J; Vollbrecht, K G; Poulin, D; Verstraete, F

2011-03-03

The original motivation to build a quantum computer came from Feynman, who imagined a machine capable of simulating generic quantum mechanical systems--a task that is believed to be intractable for classical computers. Such a machine could have far-reaching applications in the simulation of many-body quantum physics in condensed-matter, chemical and high-energy systems. Part of Feynman's challenge was met by Lloyd, who showed how to approximately decompose the time evolution operator of interacting quantum particles into a short sequence of elementary gates, suitable for operation on a quantum computer. However, this left open the problem of how to simulate the equilibrium and static properties of quantum systems. This requires the preparation of ground and Gibbs states on a quantum computer. For classical systems, this problem is solved by the ubiquitous Metropolis algorithm, a method that has basically acquired a monopoly on the simulation of interacting particles. Here we demonstrate how to implement a quantum version of the Metropolis algorithm. This algorithm permits sampling directly from the eigenstates of the Hamiltonian, and thus evades the sign problem present in classical simulations. A small-scale implementation of this algorithm should be achievable with today's technology.

Massively parallel support for a case-based planning system

NASA Technical Reports Server (NTRS)

Kettler, Brian P.; Hendler, James A.; Anderson, William A.

1993-01-01

Case-based planning (CBP), a kind of case-based reasoning, is a technique in which previously generated plans (cases) are stored in memory and can be reused to solve similar planning problems in the future. CBP can save considerable time over generative planning, in which a new plan is produced from scratch. CBP thus offers a potential (heuristic) mechanism for handling intractable problems. One drawback of CBP systems has been the need for a highly structured memory to reduce retrieval times. This approach requires significant domain engineering and complex memory indexing schemes to make these planners efficient. In contrast, our CBP system, CaPER, uses a massively parallel frame-based AI language (PARKA) and can do extremely fast retrieval of complex cases from a large, unindexed memory. The ability to do fast, frequent retrievals has many advantages: indexing is unnecessary; very large case bases can be used; memory can be probed in numerous alternate ways; and queries can be made at several levels, allowing more specific retrieval of stored plans that better fit the target problem with less adaptation. In this paper we describe CaPER's case retrieval techniques and some experimental results showing its good performance, even on large case bases.

Spike: Artificial intelligence scheduling for Hubble space telescope

NASA Technical Reports Server (NTRS)

Johnston, Mark; Miller, Glenn; Sponsler, Jeff; Vick, Shon; Jackson, Robert

1990-01-01

Efficient utilization of spacecraft resources is essential, but the accompanying scheduling problems are often computationally intractable and are difficult to approximate because of the presence of numerous interacting constraints. Artificial intelligence techniques were applied to the scheduling of the NASA/ESA Hubble Space Telescope (HST). This presents a particularly challenging problem since a yearlong observing program can contain some tens of thousands of exposures which are subject to a large number of scientific, operational, spacecraft, and environmental constraints. New techniques were developed for machine reasoning about scheduling constraints and goals, especially in cases where uncertainty is an important scheduling consideration and where resolving conflicts among conflicting preferences is essential. These technique were utilized in a set of workstation based scheduling tools (Spike) for HST. Graphical displays of activities, constraints, and schedules are an important feature of the system. High level scheduling strategies using both rule based and neural network approaches were developed. While the specific constraints implemented are those most relevant to HST, the framework developed is far more general and could easily handle other kinds of scheduling problems. The concept and implementation of the Spike system are described along with some experiments in adapting Spike to other spacecraft scheduling domains.

Progress Towards Treatment and Cure of Epidermolysis Bullosa: Summary of the DEBRA International Research Symposium EB2015

PubMed Central

Uitto, Jouni; Tuderman, Leena Bruckner; Christiano, Angela M.; McGrath, John A.; Has, Cristina; South, Andrew P.; Kopelan, Brett; Robinson, E. Clare

2015-01-01

Epidermolysis bullosa (EB), a group of complex heritable blistering diseases, is the topic of triennial research meetings organized by DEBRA International, the umbrella of patient advocacy organizations. The DEBRA 2015 Research Conference, held in May 2015, brought together investigators and clinicians from around the world working at the forefront of EB research. Discussing the state-of-the-art approaches from a wide range of disciplines, there was a palpable excitement at this conference brought about by the optimism about applying new sequencing techniques, genome editing, protein replacement, autologous and allogeneic stem cell therapy, innovations in cancer biology, revertant mosaicism and iPSC techniques, all of which are aimed at developing new therapies for EB. Many in the field who have participated in EB research for many years were especially enthusiastic and felt that, possibly for the first time, the field seems uniquely poised to bring these new tools to effectively tackle EB using multiple complementary approaches towards improved quality of life and eventually a cure for patients suffering from EB, a currently intractable disease. PMID:26802230

The structure of creative cognition in the human brain

PubMed Central

Jung, Rex E.; Mead, Brittany S.; Carrasco, Jessica; Flores, Ranee A.

2013-01-01

Creativity is a vast construct, seemingly intractable to scientific inquiry—perhaps due to the vague concepts applied to the field of research. One attempt to limit the purview of creative cognition formulates the construct in terms of evolutionary constraints, namely that of blind variation and selective retention (BVSR). Behaviorally, one can limit the “blind variation” component to idea generation tests as manifested by measures of divergent thinking. The “selective retention” component can be represented by measures of convergent thinking, as represented by measures of remote associates. We summarize results from measures of creative cognition, correlated with structural neuroimaging measures including structural magnetic resonance imaging (sMRI), diffusion tensor imaging (DTI), and proton magnetic resonance spectroscopy (1H-MRS). We also review lesion studies, considered to be the “gold standard” of brain-behavioral studies. What emerges is a picture consistent with theories of disinhibitory brain features subserving creative cognition, as described previously (Martindale, 1981). We provide a perspective, involving aspects of the default mode network (DMN), which might provide a “first approximation” regarding how creative cognition might map on to the human brain. PMID:23847503

A Stereological Study of Synapse Number in the Epileptic Human Hippocampus

PubMed Central

Alonso-Nanclares, Lidia; Kastanauskaite, Asta; Rodriguez, Jose-Rodrigo; Gonzalez-Soriano, Juncal; DeFelipe, Javier

2011-01-01

Hippocampal sclerosis is the most frequent pathology encountered in resected mesial temporal structures from patients with intractable temporal lobe epilepsy (TLE). Here, we have used stereological methods to compare the overall density of synapses and neurons between non-sclerotic and sclerotic hippocampal tissue obtained by surgical resection from patients with TLE. Specifically, we examined the possible changes in the subiculum and CA1, regions that seem to be critical for the development and/or maintenance of seizures in these patients. We found a remarkable decrease in synaptic and neuronal density in the sclerotic CA1, and while the subiculum from the sclerotic hippocampus did not display changes in synaptic density, the neuronal density was higher. Since the subiculum from the sclerotic hippocampus displays a significant increase in neuronal density, as well as a various other neurochemical changes, we propose that the apparently normal subiculum from the sclerotic hippocampus suffers profound alterations in neuronal circuits at both the molecular and synaptic level that are likely to be critical for the development or maintenance of seizure activity. PMID:21390290

Obstructive sleep apnea and stroke: links to health disparities☆, ☆☆

PubMed Central

Ramos, Alberto R.; Seixas, Azizi; Dib, Salim I.

2018-01-01

Obstructive sleep apnea (OSA) is a novel cardiovascular and cerebrovascular risk factor that presents unique opportunities to understand and reduce seemingly intractable stroke disparity among non-Hispanic blacks and Hispanic/Latinos. Individuals from these 2 groups have up to a 2-fold risk of stroke and greater burden of OSA. Obstructive sleep apnea directly and indirectly increases risk of stroke through a variety of autonomic, chemical, and inflammatory mechanisms and vascular risk factors such as hypertension, obesity, and diabetes mellitus. Untreated OSA exacerbates poststroke prognosis, as it may also influence rehabilitation efforts and functional outcomes such as cognitive function after a stroke. Conversely, treatment of OSA may reduce the risk of stroke and may yield better poststroke prognosis. Unfortunately, in racial/ethnic minority groups, there are limited awareness, knowledge, and screening opportunities for OSA. Increasing awareness and improving screening strategies for OSA in minorities may alleviate stroke risk burden and improve stroke outcomes in these populations. This review article is intended to highlight the epidemiology, clinical characteristics, pathophysiology, diagnosis, and treatment of OSA in relation to stroke risk, with an emphasis on race-ethnic disparities. PMID:29073399

Successful control of intractable nausea and vomiting requiring combined ondansetron and haloperidol in a patient with advanced cancer.

PubMed

Cole, R M; Robinson, F; Harvey, L; Trethowan, K; Murdoch, V

1994-01-01

Chemically induced nausea and vomiting is a common symptom of advanced cancer effected through stimulation of dopamine (D2) or serotonin (5-HT3) receptors located in the chemoreceptor trigger zone (CTZ). These may be blocked by therapeutic doses of haloperidol and ondansetron, respectively. This case, reporting on a single patient acting as her own control, establishes that combined blockade of these receptors is sometimes required to relieve intractable nausea and vomiting. It also demonstrates the value of clinical review, audit of care, and quality assurance in the palliative care setting.

SNF5 Mutation Leads to Intractable Pain in Schwannomatosis Patients

DTIC Science & Technology

2013-07-01

in schwannomatosis patients PRINCIPAL INVESTIGATOR: Steven G. Matsumoto...AND SUBTITLE 5a. CONTRACT NUMBER SNF5 mutation leads to intractable pain in schwannomatosis patients 5b. GRANT NUMBER W81XWH-11-1-0143 5c...Conclusion…………………………………………………………………………… 6 References……………………………………………………………………………. 7 Introduction. Schwannomatosis is a

Emotions in conflicts: understanding emotional processes sheds light on the nature and potential resolution of intractable conflicts.

PubMed

Halperin, Eran; Tagar, Michal Reifen

2017-10-01

In recent years, researchers have been making substantial advances in understanding the central role of emotions in intractable conflict. We now know that discrete emotions uniquely shape policy preferences in conflict through their unique emotional goals and action tendencies in all stages of conflict including conflict management, conflict resolution and reconciliation. Drawing on this understanding, recent research also points to emotion regulation as a path to reduce conflict and advance peace, exploring both direct and indirect strategies of emotion regulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Strategies for reducing large fMRI data sets for independent component analysis.

PubMed

Wang, Ze; Wang, Jiongjiong; Calhoun, Vince; Rao, Hengyi; Detre, John A; Childress, Anna R

2006-06-01

In independent component analysis (ICA), principal component analysis (PCA) is generally used to reduce the raw data to a few principal components (PCs) through eigenvector decomposition (EVD) on the data covariance matrix. Although this works for spatial ICA (sICA) on moderately sized fMRI data, it is intractable for temporal ICA (tICA), since typical fMRI data have a high spatial dimension, resulting in an unmanageable data covariance matrix. To solve this problem, two practical data reduction methods are presented in this paper. The first solution is to calculate the PCs of tICA from the PCs of sICA. This approach works well for moderately sized fMRI data; however, it is highly computationally intensive, even intractable, when the number of scans increases. The second solution proposed is to perform PCA decomposition via a cascade recursive least squared (CRLS) network, which provides a uniform data reduction solution for both sICA and tICA. Without the need to calculate the covariance matrix, CRLS extracts PCs directly from the raw data, and the PC extraction can be terminated after computing an arbitrary number of PCs without the need to estimate the whole set of PCs. Moreover, when the whole data set becomes too large to be loaded into the machine memory, CRLS-PCA can save data retrieval time by reading the data once, while the conventional PCA requires numerous data retrieval steps for both covariance matrix calculation and PC extractions. Real fMRI data were used to evaluate the PC extraction precision, computational expense, and memory usage of the presented methods.

The Convergence of Intelligences

NASA Astrophysics Data System (ADS)

Diederich, Joachim

Minsky (1985) argued an extraterrestrial intelligence may be similar to ours despite very different origins. ``Problem- solving'' offers evolutionary advantages and individuals who are part of a technical civilisation should have this capacity. On earth, the principles of problem-solving are the same for humans, some primates and machines based on Artificial Intelligence (AI) techniques. Intelligent systems use ``goals'' and ``sub-goals'' for problem-solving, with memories and representations of ``objects'' and ``sub-objects'' as well as knowledge of relations such as ``cause'' or ``difference.'' Some of these objects are generic and cannot easily be divided into parts. We must, therefore, assume that these objects and relations are universal, and a general property of intelligence. Minsky's arguments from 1985 are extended here. The last decade has seen the development of a general learning theory (``computational learning theory'' (CLT) or ``statistical learning theory'') which equally applies to humans, animals and machines. It is argued that basic learning laws will also apply to an evolved alien intelligence, and this includes limitations of what can be learned efficiently. An example from CLT is that the general learning problem for neural networks is intractable, i.e. it cannot be solved efficiently for all instances (it is ``NP-complete''). It is the objective of this paper to show that evolved intelligences will be constrained by general learning laws and will use task-decomposition for problem-solving. Since learning and problem-solving are core features of intelligence, it can be said that intelligences converge despite very different origins.

Explicit integration with GPU acceleration for large kinetic networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brock, Benjamin; Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830; Belt, Andrew

2015-12-01

We demonstrate the first implementation of recently-developed fast explicit kinetic integration algorithms on modern graphics processing unit (GPU) accelerators. Taking as a generic test case a Type Ia supernova explosion with an extremely stiff thermonuclear network having 150 isotopic species and 1604 reactions coupled to hydrodynamics using operator splitting, we demonstrate the capability to solve of order 100 realistic kinetic networks in parallel in the same time that standard implicit methods can solve a single such network on a CPU. This orders-of-magnitude decrease in computation time for solving systems of realistic kinetic networks implies that important coupled, multiphysics problems inmore » various scientific and technical fields that were intractable, or could be simulated only with highly schematic kinetic networks, are now computationally feasible.« less

Rapid Treatment of Subungual Onychomycosis Using Controlled Micro Nail Penetration and Terbinafine Solution.

PubMed

Bristow, Ivan; Baran, Robert; Score, Michelle

2016-08-01

Onychomycosis continues to be a common and intractable problem in adults, often responding poorly to topical treatment due to limited drug penetration of the nail plate. Improving penetration has been attempted previously by chemical and physical means with some success. The authors present three cases of toenail onychomycosis treated topical terbinafine 1% solution using controlled micro-penetration of the nail using a novel intelligent nail drill system which is able to drill nail plate without penetrating the delicate nail bed beneath. The cases illustrate how the device has been successfully employed to deliver the anti-fungal drug directly and rapidly to the site of infection with minimal side effects or complications, whilst maintaining the nail integrity.

J Drugs Dermatol. 2016;15(8):974-978.

Towards quantum chemistry on a quantum computer.

PubMed

Lanyon, B P; Whitfield, J D; Gillett, G G; Goggin, M E; Almeida, M P; Kassal, I; Biamonte, J D; Mohseni, M; Powell, B J; Barbieri, M; Aspuru-Guzik, A; White, A G

2010-02-01

Exact first-principles calculations of molecular properties are currently intractable because their computational cost grows exponentially with both the number of atoms and basis set size. A solution is to move to a radically different model of computing by building a quantum computer, which is a device that uses quantum systems themselves to store and process data. Here we report the application of the latest photonic quantum computer technology to calculate properties of the smallest molecular system: the hydrogen molecule in a minimal basis. We calculate the complete energy spectrum to 20 bits of precision and discuss how the technique can be expanded to solve large-scale chemical problems that lie beyond the reach of modern supercomputers. These results represent an early practical step toward a powerful tool with a broad range of quantum-chemical applications.

Visualizing a silicon quantum computer

NASA Astrophysics Data System (ADS)

Sanders, Barry C.; Hollenberg, Lloyd C. L.; Edmundson, Darran; Edmundson, Andrew

2008-12-01

Quantum computation is a fast-growing, multi-disciplinary research field. The purpose of a quantum computer is to execute quantum algorithms that efficiently solve computational problems intractable within the existing paradigm of 'classical' computing built on bits and Boolean gates. While collaboration between computer scientists, physicists, chemists, engineers, mathematicians and others is essential to the project's success, traditional disciplinary boundaries can hinder progress and make communicating the aims of quantum computing and future technologies difficult. We have developed a four minute animation as a tool for representing, understanding and communicating a silicon-based solid-state quantum computer to a variety of audiences, either as a stand-alone animation to be used by expert presenters or embedded into a longer movie as short animated sequences. The paper includes a generally applicable recipe for successful scientific animation production.

Learning algorithm in restricted Boltzmann machines using Kullback-Leibler importance estimation procedure

NASA Astrophysics Data System (ADS)

Yasuda, Muneki; Sakurai, Tetsuharu; Tanaka, Kazuyuki

Restricted Boltzmann machines (RBMs) are bipartite structured statistical neural networks and consist of two layers. One of them is a layer of visible units and the other one is a layer of hidden units. In each layer, any units do not connect to each other. RBMs have high flexibility and rich structure and have been expected to applied to various applications, for example, image and pattern recognitions, face detections and so on. However, most of computational models in RBMs are intractable and often belong to the class of NP-hard problem. In this paper, in order to construct a practical learning algorithm for them, we employ the Kullback-Leibler Importance Estimation Procedure (KLIEP) to RBMs, and give a new scheme of practical approximate learning algorithm for RBMs based on the KLIEP.

A Scheme to Optimize Flow Routing and Polling Switch Selection of Software Defined Networks.

PubMed

Chen, Huan; Li, Lemin; Ren, Jing; Wang, Yang; Zhao, Yangming; Wang, Xiong; Wang, Sheng; Xu, Shizhong

2015-01-01

This paper aims at minimizing the communication cost for collecting flow information in Software Defined Networks (SDN). Since flow-based information collecting method requires too much communication cost, and switch-based method proposed recently cannot benefit from controlling flow routing, jointly optimize flow routing and polling switch selection is proposed to reduce the communication cost. To this end, joint optimization problem is formulated as an Integer Linear Programming (ILP) model firstly. Since the ILP model is intractable in large size network, we also design an optimal algorithm for the multi-rooted tree topology and an efficient heuristic algorithm for general topology. According to extensive simulations, it is found that our method can save up to 55.76% communication cost compared with the state-of-the-art switch-based scheme.

Corrected Mean-Field Model for Random Sequential Adsorption on Random Geometric Graphs

NASA Astrophysics Data System (ADS)

Dhara, Souvik; van Leeuwaarden, Johan S. H.; Mukherjee, Debankur

2018-03-01

A notorious problem in mathematics and physics is to create a solvable model for random sequential adsorption of non-overlapping congruent spheres in the d-dimensional Euclidean space with d≥ 2 . Spheres arrive sequentially at uniformly chosen locations in space and are accepted only when there is no overlap with previously deposited spheres. Due to spatial correlations, characterizing the fraction of accepted spheres remains largely intractable. We study this fraction by taking a novel approach that compares random sequential adsorption in Euclidean space to the nearest-neighbor blocking on a sequence of clustered random graphs. This random network model can be thought of as a corrected mean-field model for the interaction graph between the attempted spheres. Using functional limit theorems, we characterize the fraction of accepted spheres and its fluctuations.

Does ketogenic diet have any negative effect on cardiac systolic and diastolic functions in children with intractable epilepsy?: One-year follow-up results.

PubMed

Ozdemir, Rahmi; Kucuk, Mehmet; Guzel, Orkide; Karadeniz, Cem; Yilmaz, Unsal; Mese, Timur

2016-10-01

The ketogenic diet (KD) has been referred to as an "effective therapy with side effects" for children with intractable epilepsy. Among the most recognized adverse effects, there are cardiac conduction abnormalities, vascular and myocardial dysfunction. However, very limited and controversial data are available regarding the effects of the KD on cardiac functions. We sought to analyze the mid-term effect of ketogenic diet on cardiac functions in patients with intractable epilepsy who received a ketogenic diet for at least 12months using conventional and relatively new imaging techniques. This prospective study included 61 patients with intractable epilepsy who received ketogenic diet for at least 12months. Clinical examinations, serum carnitine and selenium levels as well as electrocardiographic and echocardiographic examinations were scheduled prior to the procedure and at 1, 3, 6 and 12months. We utilized two-dimensional, M-mode, colored Doppler, spectral Doppler and pulsed wave tissue Doppler imaging techniques to investigate ventricular systolic and diastolic functions of this subgroup of patients. In our study, there was no significant difference after 1year of KD therapy compared to baseline values-except a significantly decreased A wave velocity-in terms of pulse wave Doppler echocardiographic measurements of the diastolic function. The tissue Doppler measurements obtained from the lateral wall of tricuspide and mitral annuli were not different at baseline and at month 12 of the treatment, as well. The ketogenic diet appears to have no disturbing effect on ventricular functions in epileptic children in the midterm. Copyright © 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Lexicon before and after epilepsy surgery in adolescents.

PubMed

Meekes, Joost; Chanturidze, Mari; Braams, Olga B; Braun, Kees P J; van Rijen, Peter C; Hendriks, Marc P H; Jennekens-Schinkel, Aag; van Nieuwenhuizen, Onno

2016-05-01

Poor performance on confrontation naming tasks by children and adolescents with pharmacologically intractable epilepsy has been interpreted as indicating impairments of lexicon, that is, the store of words in long-term memory. However, confrontation naming performance crucially depends not only on word knowledge but also on other functions such as fluency. We applied an alternative method to assess lexicon with the aim of tracing deficits in lexicon before and after surgery in adolescents with pharmacologically intractable epilepsy. Sixteen patients and 32 age- and sex-matched controls completed the Dutch version of the controlled oral word production task. Responses were used to calculate indices of lexical fluency (retrieval efficiency), lexical breadth (vocabulary size), and lexical depth (knowledge of word properties), as well as use of search strategies. Adolescents with pharmacologically intractable epilepsy had lower lexical fluency scores than healthy peers, but did not differ from them on the dimensions of lexical breadth and lexical depth. Patients demonstrated reduced use of search strategies. In fact, the difference in lexical fluency between patients and controls disappeared after controlling for Full Scale IQ (obtained using the Dutch version of the 3rd edition of the Wechsler Intelligence Scale for Children (WISC-IIINL; Kort et al., 2005; Wechsler, 2002) or-for older children-the Dutch version of the first edition of the Kaufman Adult and Adolescent Intelligence Test (KAIT; Kaufman & Kaufman, 1993; Mulder, Dekker, & Dekker, 2004) and use of search strategies. In patients, changes in the use of the antiepileptic drug carbamazepine were associated with lexical fluency. Adolescents with pharmacologically intractable epilepsy differ from their healthy peers mainly in lexical fluency, rather than word knowledge per se. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A good preoperative response to transcutaneous electrical nerve stimulation predicts a better therapeutic effect of implanted occipital nerve stimulation in pharmacologically intractable headaches.

PubMed

Nguyen, Jean-Paul; Nizard, Julien; Kuhn, Emmanuelle; Carduner, Florence; Penverne, Frédérique; Verleysen-Robin, Marie-Christine; Terreaux, Luc; de Gaalon, Solène; Raoul, Sylvie; Lefaucheur, Jean-Pascal

2016-02-01

Occipital nerve stimulation (ONS) is a surgical approach to treat patients with medically intractable chronic headache disorders. However, no preoperative test has been yet validated to allow candidates to be selected for implantation. In this study, the analgesic efficacy of transcutaneous electrical nerve stimulation (TENS) was tested for 1 to 3 months in 41 patients with pharmacologically intractable headache disorders of various origins, using a new technique of electrode placement over the occipital nerve. ONS electrodes were subsequently implanted in 33 patients (occipital neuralgia [n=15], cervicogenic headache [n=7], cluster headache [n=6], chronic migraine [n=5]) who had responded at least moderately to TENS. Assessment was performed up to five years after implantation (three years on average), based on the mean and maximum daily pain intensity scored on a 0-10 visual analogue scale and the number of headache days per month. Both TENS and chronic ONS therapy were found to be efficacious (57-76% improvement compared to baseline on the various clinical variables). The efficacy of ONS was better in cases of good or very good preoperative response to TENS than in cases of moderate response to TENS. Implanted ONS may be a valuable therapeutic option in the long term for patients with pharmacologically intractable chronic headache. Although we cannot conclude in patients with poor or no response to TENS, a good or very good response to TENS can support the indication of ONS therapy. This preoperative test could particularly be useful in patients with chronic migraine, in whom it may be difficult to indicate an invasive technique of cranial neurostimulation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Resting-State Functional MR Imaging for Determining Language Laterality in Intractable Epilepsy.

PubMed

DeSalvo, Matthew N; Tanaka, Naoaki; Douw, Linda; Leveroni, Catherine L; Buchbinder, Bradley R; Greve, Douglas N; Stufflebeam, Steven M

2016-10-01

Purpose To measure the accuracy of resting-state functional magnetic resonance (MR) imaging in determining hemispheric language dominance in patients with medically intractable focal epilepsies against the results of an intracarotid amobarbital procedure (IAP). Materials and Methods This study was approved by the institutional review board, and all subjects gave signed informed consent. Data in 23 patients with medically intractable focal epilepsy were retrospectively analyzed. All 23 patients were candidates for epilepsy surgery and underwent both IAP and resting-state functional MR imaging as part of presurgical evaluation. Language dominance was determined from functional MR imaging data by calculating a laterality index (LI) after using independent component analysis. The accuracy of this method was assessed against that of IAP by using a variety of thresholds. Sensitivity and specificity were calculated by using leave-one-out cross validation. Spatial maps of language components were qualitatively compared among each hemispheric language dominance group. Results Measurement of hemispheric language dominance with resting-state functional MR imaging was highly concordant with IAP results, with up to 96% (22 of 23) accuracy, 96% (22 of 23) sensitivity, and 96% (22 of 23) specificity. Composite language component maps in patients with typical language laterality consistently included classic language areas such as the inferior frontal gyrus, the posterior superior temporal gyrus, and the inferior parietal lobule, while those of patients with atypical language laterality also included non-classical language areas such as the superior and middle frontal gyri, the insula, and the occipital cortex. Conclusion Resting-state functional MR imaging can be used to measure language laterality in patients with medically intractable focal epilepsy. (©) RSNA, 2016 Online supplemental material is available for this article.

Resting-State Functional MR Imaging for Determining Language Laterality in Intractable Epilepsy

PubMed Central

Tanaka, Naoaki; Douw, Linda; Leveroni, Catherine L.; Buchbinder, Bradley R.; Greve, Douglas N.; Stufflebeam, Steven M.

2016-01-01

Purpose To measure the accuracy of resting-state functional magnetic resonance (MR) imaging in determining hemispheric language dominance in patients with medically intractable focal epilepsies against the results of an intracarotid amobarbital procedure (IAP). Materials and Methods This study was approved by the institutional review board, and all subjects gave signed informed consent. Data in 23 patients with medically intractable focal epilepsy were retrospectively analyzed. All 23 patients were candidates for epilepsy surgery and underwent both IAP and resting-state functional MR imaging as part of presurgical evaluation. Language dominance was determined from functional MR imaging data by calculating a laterality index (LI) after using independent component analysis. The accuracy of this method was assessed against that of IAP by using a variety of thresholds. Sensitivity and specificity were calculated by using leave-one-out cross validation. Spatial maps of language components were qualitatively compared among each hemispheric language dominance group. Results Measurement of hemispheric language dominance with resting-state functional MR imaging was highly concordant with IAP results, with up to 96% (22 of 23) accuracy, 96% (22 of 23) sensitivity, and 96% (22 of 23) specificity. Composite language component maps in patients with typical language laterality consistently included classic language areas such as the inferior frontal gyrus, the posterior superior temporal gyrus, and the inferior parietal lobule, while those of patients with atypical language laterality also included non-classical language areas such as the superior and middle frontal gyri, the insula, and the occipital cortex. Conclusion Resting-state functional MR imaging can be used to measure language laterality in patients with medically intractable focal epilepsy. © RSNA, 2016 Online supplemental material is available for this article. PMID:27467465

Preliminary experience with epsilon aminocaproic acid for treatment of intractable upper tract hematuria in children with hematological disorders.

PubMed

Kaye, Jonathan D; Smith, Edwin A; Kirsch, Andrew J; Cerwinka, Wolfgang H; Elmore, James M

2010-09-01

Gross, intractable hematuria is rare in children. Although the role of epsilon aminocaproic acid in the management of refractory hematuria is well established in the adult population, few data exist about its use in children for this indication. We present our initial experience with epsilon aminocaproic acid for the treatment of intractable hematuria after more conservative measures failed, and propose an algorithm for administration of epsilon aminocaproic acid in children. We reviewed the charts of all patients treated with epsilon aminocaproic acid for intractable gross hematuria at our institution during a period of 36 months. All patients underwent hematological evaluation and any underlying bleeding dyscrasias were addressed. All patients also underwent renal and bladder ultrasound, retrograde pyelogram and ureteroscopy. Demographic information, medical and surgical histories, and epsilon aminocaproic acid dosing and outcomes were recorded. Three boys and 1 girl 11 to 17 years old were treated with epsilon aminocaproic acid. Three patients had sickle trait (1 with nutcracker phenomenon) and 1 had hemophilia A. Three patients required packed red blood cell transfusions to maintain hematocrit. Three renal angiograms were performed, all of which were nondiagnostic. Duration of hematuria ranged from 1 to 52 weeks before administration of epsilon aminocaproic acid. Endoscopic evaluation demonstrated hematuria localized to 1 ureteral orifice in all 4 patients. All patients received 100 mg/kg epsilon aminocaproic acid orally every 6 hours, which uniformly led to cessation of hematuria. Epsilon aminocaproic acid is useful for the management of gross refractory hematuria when more conservative measures fail. Because of its potential side effects, it should be used cautiously. 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

CBD-enriched medical cannabis for intractable pediatric epilepsy: The current Israeli experience.

PubMed

Tzadok, Michal; Uliel-Siboni, Shimrit; Linder, Ilan; Kramer, Uri; Epstein, Orna; Menascu, Shay; Nissenkorn, Andrea; Yosef, Omer Bar; Hyman, Eli; Granot, Dorit; Dor, Michael; Lerman-Sagie, Tali; Ben-Zeev, Bruria

2016-02-01

To describe the experience of five Israeli pediatric epilepsy clinics treating children and adolescents diagnosed as having intractable epilepsy with a regimen of medical cannabis oil. A retrospective study describing the effect of cannabidiol (CBD)-enriched medical cannabis on children with epilepsy. The cohort included 74 patients (age range 1-18 years) with intractable epilepsy resistant to >7 antiepileptic drugs. Forty-nine (66%) also failed a ketogenic diet, vagal nerve stimulator implantation, or both. They all started medical cannabis oil treatment between 2-11/2014 and were treated for at least 3 months (average 6 months). The selected formula contained CBD and tetrahydrocannabinol at a ratio of 20:1 dissolved in olive oil. The CBD dose ranged from 1 to 20mg/kg/d. Seizure frequency was assessed by parental report during clinical visits. CBD treatment yielded a significant positive effect on seizure load. Most of the children (66/74, 89%) reported reduction in seizure frequency: 13 (18%) reported 75-100% reduction, 25 (34%) reported 50-75% reduction, 9 (12%) reported 25-50% reduction, and 19 (26%) reported <25% reduction. Five (7%) patients reported aggravation of seizures which led to CBD withdrawal. In addition, we observed improvement in behavior and alertness, language, communication, motor skills and sleep. Adverse reactions included somnolence, fatigue, gastrointestinal disturbances and irritability leading to withdrawal of cannabis use in 5 patients. The results of this multicenter study on CBD treatment for intractable epilepsy in a population of children and adolescents are highly promising. Further prospective, well-designed clinical trials using enriched CBD medical cannabis are warranted. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Intractable bone marrow edema syndrome of the hip.

PubMed

Gao, Fuqiang; Sun, Wei; Li, Zirong; Guo, Wanshou; Kush, Nepali; Ozaki, Koji

2015-04-01

There is a need for an effective and noninvasive treatment for intractable bone marrow edema syndrome of the hip. Forty-six patients with intractable bone marrow edema syndrome of the hip were retrospectively studied to compare the short-term clinical effects of treatment with high-energy extracorporeal shock wave therapy vs femoral head core decompression. The postoperative visual analog scale score decreased significantly more in the extracorporeal shock wave therapy group compared with the femoral head core decompression group (P<.05). For unilateral lesions, postoperative Harris Hip Scores for all hips in the extracorporeal shock wave therapy group were more significantly improved than Harris Hip Scores for all hips in the femoral head core decompression group (P<.05). Patients who underwent extracorporeal shock wave therapy also resumed daily activities significantly earlier. Average overall operative time was similar in both groups. Symptoms disappeared significantly sooner in the extracorporeal shock wave therapy group in patients with both unilateral (P<.01) and bilateral lesions (P<.05). Hospital costs were significantly lower with extracorporeal shock wave therapy compared with femoral head core decompression. The intraoperative fluoroscopy radiation dose was lower in extracorporeal shock wave therapy than in femoral head core decompression for both unilateral (P<.05) and bilateral lesions (P<.01). On magnetic resonance imaging (MRI), bone marrow edema improved in all patients during the follow-up period. After extracorporeal shock wave therapy, all patients remained pain-free and had normal findings on posttreatment radiographs and MRI scans. Extracorporeal shock wave therapy appears to be a valid, reliable, and noninvasive tool for rapidly resolving intractable bone marrow edema syndrome of the hip, and it has a low complication rate and relatively low cost compared with other conservative and surgical treatment approaches. Copyright 2015, SLACK Incorporated.

Health insurance system and payments provided to patients for the management of severe acute pancreatitis in Japan.

PubMed

Yoshida, Masahiro; Takada, Tadahiro; Kawarada, Yoshifumi; Hirata, Koichi; Mayumi, Toshihiko; Sekimoto, Miho; Hirota, Masahiko; Kimura, Yasutoshi; Takeda, Kazunori; Isaji, Shuji; Koizumi, Masaru; Otsuki, Makoto; Matsuno, Seiki

2006-01-01

The health insurance system in Japan is based upon the Universal Medical Care Insurance System, which gives all citizens the right to join an insurance scheme of their own choice, as guaranteed by the provisions of Article 25 of the Constitution of Japan, which states: "All people shall have the right to maintain the minimum standards of wholesome and cultured living." The health care system in Japan includes national medical insurance, nursing care for the elderly, and government payments for the treatment of intractable diseases. Medical insurance provisions are handled by Employee's Health Insurance (Social Insurance), which mainly covers employees of private companies and their families, and by National Health Insurance, which provides for the needs of self-employed people. Both schemes have their own medical care service programs for retired persons and their families. The health care system for the elderly covers people 75 years of age and over and bedridden people 65 years of age and over. There is also a system under which the government pays all or part of medical expenses, and/or pays medical expenses not covered by insurance. This is referred to collectively as the "medical expenses payment system" and includes the provision of medical assistance for specified intractable diseases. Because severe acute pancreatitis has a high mortality rate, it is specified as an intractable disease. In order to lower the mortality rate of various diseases, including severe acute pancreatitis, the specification system has been adopted by the government. The cost of treatment for severe acute pancreatitis is paid in full by the government from the date the application is made for a certificate verifying that the patient has an intractable disease.

[Effect of neurolysis on intractable greater occipital nerve neuralgia].

PubMed

Tian, Yunhu; Liu, Ya; Liu, Huancai

2007-09-01

To investigate the effect of neurolysis on intractable greater occipital nerve neuralgia. From March 1998 to August 2005, twenty-six patients suffering from intractable greater occipital nerve neuralgia were treated. There were 12 males and 14 females with an average age of 52 years (ranged 38-63 years). The disease course was 3-7 years. Sixteen cases had a long duration of work with bowing head, 5 cases symptoms appeared after trauma, and others had no identified causes. The visual analogue scales (VAS) scoring was 6.0 to 9.5, averaged 8. 6. Seven cases were treated by apocope of obliquus capitis inferior under general anaesthesia and 19 cases were treated by neurolysis of greater occipital nerve under local anaesthesia. The compression mass were examined. Symptoms ameliorated or disappeared in 26 cases immediately after operation. The wounds healed by first intention. The pathological results of the removal mass included lymph node (3 cases), neurilemmoma (2 cases) and scar (5 cases). The VAS scoring of 26 cases was 0 to 5 (average, 2) 3 days after operation. Twenty-three cases were followed up for 1 to 3 years. The VAS scoring of 23 cases was 0 to 4.5 ( average, 1.9) 1 months after operation. Only two cases recurred and the symptoms were ameliorated. Pain aggavated after tiredness and reliveed after oral anti-inflammatory analgesics in 6 cases. No relapse occurred in the others. The complete neurolysis of greater occipital nerve (including apocope of obliquus capitis inferior, release between the cucullaris and semispinalis) which make the greater occipital nerve goes without any compression is the key point to treat intractable greater occipital nerve neuralgia.

Complexity seems to open a way towards a new Aristotelian-Thomistic ontology.

PubMed

Strumia, Alberto

2007-01-01

Today's sciences seem to converge all towards very similar foundational questions. Such claims, both of epistemological and ontological nature, seem to rediscover, in a new fashion some of the most relevant topics of ancient Greek and Mediaeval philosophy of nature, logic and metaphysics, such as the problem of the relationship between the whole and its parts (non redictionism), the problems of the paradoxes arising from the attempt to conceive the entity like an univocal concept (analogy and analogia entis), the problem of the mind-body relationship and that of an adequate cognitive theory (abstraction and immaterial nature of the mind), the complexity of some physical, chemical and biological systems and global properties arising from information (matter-form theory), etc. Medicine too is involved in some of such relevant questions and cannot avoid to take them into a special account.

The Five Marks of the Mental

PubMed Central

Pernu, Tuomas K.

2017-01-01

The mental realm seems different to the physical realm; the mental is thought to be dependent on, yet distinct from the physical. But how, exactly, are the two realms supposed to be different, and what, exactly, creates the seemingly insurmountable juxtaposition between the mental and the physical? This review identifies and discusses five marks of the mental, features that set characteristically mental phenomena apart from the characteristically physical phenomena. These five marks (intentionality, consciousness, free will, teleology, and normativity) are not presented as a set of features that define mentality. Rather, each of them is something we seem to associate with phenomena we consider mental, and each of them seems to be in tension with the physical view of reality in its own particular way. It is thus suggested how there is no single mind-body problem, but a set of distinct but interconnected problems. Each of these separate problems is analyzed, and their differences, similarities and connections are identified. This provides a useful basis for future theoretical work on psychology and philosophy of mind, that until now has too often suffered from unclarities, inadequacies, and conflations. PMID:28736537

Clinical knowledge-based inverse treatment planning

NASA Astrophysics Data System (ADS)

Yang, Yong; Xing, Lei

2004-11-01

Clinical IMRT treatment plans are currently made using dose-based optimization algorithms, which do not consider the nonlinear dose-volume effects for tumours and normal structures. The choice of structure specific importance factors represents an additional degree of freedom of the system and makes rigorous optimization intractable. The purpose of this work is to circumvent the two problems by developing a biologically more sensible yet clinically practical inverse planning framework. To implement this, the dose-volume status of a structure was characterized by using the effective volume in the voxel domain. A new objective function was constructed with the incorporation of the volumetric information of the system so that the figure of merit of a given IMRT plan depends not only on the dose deviation from the desired distribution but also the dose-volume status of the involved organs. The conventional importance factor of an organ was written into a product of two components: (i) a generic importance that parametrizes the relative importance of the organs in the ideal situation when the goals for all the organs are met; (ii) a dose-dependent factor that quantifies our level of clinical/dosimetric satisfaction for a given plan. The generic importance can be determined a priori, and in most circumstances, does not need adjustment, whereas the second one, which is responsible for the intractable behaviour of the trade-off seen in conventional inverse planning, was determined automatically. An inverse planning module based on the proposed formalism was implemented and applied to a prostate case and a head-neck case. A comparison with the conventional inverse planning technique indicated that, for the same target dose coverage, the critical structure sparing was substantially improved for both cases. The incorporation of clinical knowledge allows us to obtain better IMRT plans and makes it possible to auto-select the importance factors, greatly facilitating the inverse planning process. The new formalism proposed also reveals the relationship between different inverse planning schemes and gives important insight into the problem of therapeutic plan optimization. In particular, we show that the EUD-based optimization is a special case of the general inverse planning formalism described in this paper.

Partial monosomy Xq(Xq23 --> qter) and trisomy 4p(4p15.33 --> pter) in a woman with intractable focal epilepsy, borderline intellectual functioning, and dysmorphic features.

PubMed

Bartocci, Arnaldo; Striano, Pasquale; Mancardi, Maria Margherita; Fichera, Marco; Castiglia, Lucia; Galesi, Ornella; Michelucci, Roberto; Elia, Maurizio

2008-06-01

Studies of epilepsy associated with chromosomal abnormalities may provide information about clinical and EEG phenotypes and possibly to identify new epilepsy genes. We describe a female patient with intractable focal epilepsy, borderline intellectual functioning, and facial dysmorphisms, in whom genetic study (i.e., karyotype and array-CGH analysis) revealed a distal trisomy 4p and distal monosomy Xq. Although any genetic hypothesis remains speculative, several genes are located in the 4p chromosome segment involved in the rearrangement, some of which may be related to epilepsy.

Microorganism Nutrition Processes as a General Route for the Preparation of Bionic Nanocomposites Based on Intractable Polymers.

PubMed

Valentini, L; Bon, S Bittolo; Pugno, N M

2016-08-31

In this paper the fermentation process activated by living microorganisms of the baker's yeast is proposed as a facile assembly method of hybrid nanoparticles at liquid interface. Water dispersion of commercial baker's yeast extract used for bread production, graphene nanoplatelets (GNPs), and carbon nanotubes (CNTs) were added to oil/water interface; when the yeast is activated by adding sugar, the byproduct carbon dioxide bubbles migrate from the water phase to the oil/water interface generating a floating nanostructured film at liquid interface where it is trapped. Starting from this simple method, we propose a general approach for the stabilization of intractable poly(etheretherketone) polymeric particles with GNPs and CNTs at immiscible liquid interface. This process allowed the formation of sintered porous composites with improved mechanical properties. The porous structure of the composites gave rise to a low thermal conductivity making them good candidates for thermal insulating applications. Liquid absorption by these porous composites has been also reported. We believe that this new approach may have applications in the large scale fabrication of nanomaterials and is particularly suited for the preparation of nanocomposites starting from polymers that are intractable by solvent casting.

ST-Segment Elevation Myocardial Infarction with Acute Stent Thrombosis Presenting as Intractable Hiccups: An Unusual Case.

PubMed

Zhang, Fan; Tongo, Nosakhare Douglas; Hastings, Victoria; Kanzali, Parisa; Zhu, Ziqiang; Chadow, Hal; Rafii, Shahrokh E

2017-04-29

BACKGROUND Acute coronary syndrome (ACS) can present with atypical chest pain or symptoms not attributed to heart disease, such as indigestion. Hiccups, a benign and self-limited condition, can become persistent or intractable with overlooked underlying etiology. There are various causes of protracted hiccups, including metabolic abnormalities, psychogenic disorders, malignancy, central nervous system pathology, medications, pulmonary disorders, or gastrointestinal etiologies. It is rarely attributed to cardiac disease. CASE REPORT We report a case of intractable hiccups in a 51-year-old male with cocaine related myocardial infarction (MI) before and after stent placement. Coronary angiogram showed in-stent thrombosis of the initial intervention. Following thrombectomy, balloon angioplasty, and stent, the patient recovered well without additional episodes of hiccups. Although hiccups are not known to present with a predilection for a particular cause of myocardial ischemia, this case may additionally be explained by the sympathomimetic effects of cocaine, which lead to vasoconstriction of coronary arteries. CONCLUSIONS Hiccups associated with cardiac enzyme elevation and EKG ST-segment elevation before and after percutaneous coronary intervention (PCI) maybe a manifestation of acute MI with or without stent. The fact that this patient was a cocaine user may have contributed to the unique presentation.

[Successful treatment with chloramphenicol in four pediatric cases of intractable bacterial meningitis].

PubMed

Morita, Kayo; Abe, Yu-ichi; Itano, Atsushi; Musha, Ikuma; Koga, Takeshi; Yamazaki, Taro; Yamanouchi, Hideo

2016-01-01

Chloramphenicol (CP) is recently one of the rarely-used antibiotics. In this study, we present four patients with intractable bacterial meningitis, who were successfully treated with CP and discuss the therapeutic indications of CP in these pediatric cases. The patients were diagnosed as bacterial meningitis at the ages ranging from 2 months to 1 year and 4 months. The causative organisms found in three of the patients were H. influenzae and in the fourth patient, S. pneumoniae. According to the microbial sensitivity tests, these organisms were highly sensitive to antibiotics including ceftriaxone, meropenem and/or panipenem/betamipron. Treatment with these antibiotics was initially effective; however, recurrences of meningitis appeared in all patients. Administration of CP (100 mg/kg/day) started between the 11th and the 58th days, and was continued for 9 days up to 19 days. Their fever had disappeared within four days after the administration of CP, and it was confirmed that all patients completely recovered from meningitis. Two of the patients developed a mild degree of anemia, but soon recovered after the discontinuation of CP. None of them had neurological sequela. We recommend CP as one of the choices for the treatment of intractable bacterial meningitis.

Magnetic resonance imaging-guided laser interstitial thermal therapy as treatment for intractable insular epilepsy in children.

PubMed

Perry, M Scott; Donahue, David J; Malik, Saleem I; Keator, Cynthia G; Hernandez, Angel; Reddy, Rohit K; Perkins, Freedom F; Lee, Mark R; Clarke, Dave F

2017-12-01

OBJECTIVE Seizure onset within the insula is increasingly recognized as a cause of intractable epilepsy. Surgery within the insula is difficult, with considerable risks, given the rich vascular supply and location near critical cortex. MRI-guided laser interstitial thermal therapy (LiTT) provides an attractive treatment option for insular epilepsy, allowing direct ablation of abnormal tissue while sparing nearby normal cortex. Herein, the authors describe their experience using this technique in a large cohort of children undergoing treatment of intractable localization-related epilepsy of insular onset. METHODS The combined epilepsy surgery database of Cook Children's Medical Center and Dell Children's Hospital was queried for all cases of insular onset epilepsy treated with LiTT. Patients without at least 6 months of follow-up data and cases preoperatively designated as palliative were excluded. Patient demographics, presurgical evaluation, surgical plan, and outcome were collected from patient charts and described. RESULTS Twenty patients (mean age 12.8 years, range 6.1-18.6 years) underwent a total of 24 LiTT procedures; 70% of these patients had normal findings on MRI. Patients underwent a mean follow-up of 20.4 months after their last surgery (range 7-39 months), with 10 (50%) in Engel Class I, 1 (5%) in Engel Class II, 5 (25%) in Engel Class III, and 4 (20%) in Engel Class IV at last follow-up. Patients were discharged within 24 hours of the procedure in 15 (63%) cases, in 48 hours in 6 (24%) cases, and in more than 48 hours in the remaining cases. Adverse functional effects were experienced following 7 (29%) of the procedures: mild hemiparesis after 6 procedures (all patients experienced complete resolution or had minimal residual dysfunction by 6 months), and expressive language dysfunction after 1 procedure (resolved by 3 months). CONCLUSIONS To their knowledge, the authors present the largest cohort of pediatric patients undergoing insular surgery for treatment of intractable epilepsy. The patient outcomes suggest that LiTT can successfully treat intractable seizures originating within the insula and offers an attractive alternative to open resection. This is the first description of LiTT applied to insular epilepsy and represents one of only a few series describing the use of LiTT in children. The results indicate that seizure reduction after LiTT compares favorably to that after conventional open surgical techniques.

Effective symptomatic treatment for severe and intractable pruritus associated with severe burn-induced hypertrophic scars: A prospective, multicenter, controlled trial.

PubMed

Wu, Jun; Xu, Rui; Zhan, Rixing; Luo, Gaoxing; Niu, Xihua; Liu, Yi; Lee, Benjamin Tak-Kwong; Flury, Meinrad; Wong, Chun-Ho; Fok, Manson; Lau, Johnson Yiu-Nam

2016-08-01

Burn-induced hypertrophic scars are disfiguring and can be associated with severe and intractable pruritus. No effective treatment modalities are currently available for symptomatic control of pruritus for most patients. We assessed the effect of the Antipruritic Hydrogel (CQ-01) in the symptomatic treatment of severe and intractable pruritus associated with burn-induced hypertrophic scars in a prospective, multicenter, controlled trial. A pilot study was conducted in healthy adult volunteers to identify the most appropriate hydrogel formulation. A selected preparation called Chongqing No. 1 (CQ-01; a guar gum-based hydrogel impregnated with peppermint oil, menthol, and methyl salicylate by a nanoemulsion), showed an excellent symptomatic relief in an exploratory study in 2 patients with intractable pruritus. A statistically powered, prospective, multicenter, controlled study was then conducted in 74 patients to evaluate the efficacy and safety of a 24-h application of CQ-01 compared to a gel control and a negative control on three separate areas in each patient. Symptom assessment was based on our visual analog JW scale (ranging from 0 to 100) at baseline and various time points up to 7 days after application. Follow-up studies were conducted to determine the reproducibility of CQ-01 in repeated applications. Of the 74 enrolled subjects, the only observed adverse event was skin irritation reported in 6 patients (8%) and resolved shortly after gel removal. Compared to the baseline, the gauze negative control had a mean JW score reduction of 7; while the gel control and CQ-01 had a drop of 18 (p<0.001) and 36 (p<0.001), respectively. The CQ-01 clinical effect was significant for up to 3 days and waned slowly from 3 to 7 days. There was no statistical correlation between the treatment response and any of the demographic, patient or burn-related factors. Further studies showed a trend that repeated applications might be more effective, suggesting the absence of tachyphylaxis. This prospective, multicenter, controlled study showed that this novel hydrogel CQ-01 is safe and provides significant symptomatic relief for severe and intractable pruritus associated with hypertrophic scars, an unmet medical need for these patients. This effect is independent of the etiology of the burn trauma, extent of the scarring, and duration of the scar formation. Copyright © 2016. Published by Elsevier Ltd.

Hybrid quantum-classical hierarchy for mitigation of decoherence and determination of excited states

DOE Office of Scientific and Technical Information (OSTI.GOV)

McClean, Jarrod R.; Kimchi-Schwartz, Mollie E.; Carter, Jonathan

Using quantum devices supported by classical computational resources is a promising approach to quantum-enabled computation. One powerful example of such a hybrid quantum-classical approach optimized for classically intractable eigenvalue problems is the variational quantum eigensolver, built to utilize quantum resources for the solution of eigenvalue problems and optimizations with minimal coherence time requirements by leveraging classical computational resources. These algorithms have been placed as leaders among the candidates for the first to achieve supremacy over classical computation. Here, we provide evidence for the conjecture that variational approaches can automatically suppress even nonsystematic decoherence errors by introducing an exactly solvable channelmore » model of variational state preparation. Moreover, we develop a more general hierarchy of measurement and classical computation that allows one to obtain increasingly accurate solutions by leveraging additional measurements and classical resources. In conclusion, we demonstrate numerically on a sample electronic system that this method both allows for the accurate determination of excited electronic states as well as reduces the impact of decoherence, without using any additional quantum coherence time or formal error-correction codes.« less

Statistical benchmark for BosonSampling

NASA Astrophysics Data System (ADS)

Walschaers, Mattia; Kuipers, Jack; Urbina, Juan-Diego; Mayer, Klaus; Tichy, Malte Christopher; Richter, Klaus; Buchleitner, Andreas

2016-03-01

Boson samplers—set-ups that generate complex many-particle output states through the transmission of elementary many-particle input states across a multitude of mutually coupled modes—promise the efficient quantum simulation of a classically intractable computational task, and challenge the extended Church-Turing thesis, one of the fundamental dogmas of computer science. However, as in all experimental quantum simulations of truly complex systems, one crucial problem remains: how to certify that a given experimental measurement record unambiguously results from enforcing the claimed dynamics, on bosons, fermions or distinguishable particles? Here we offer a statistical solution to the certification problem, identifying an unambiguous statistical signature of many-body quantum interference upon transmission across a multimode, random scattering device. We show that statistical analysis of only partial information on the output state allows to characterise the imparted dynamics through particle type-specific features of the emerging interference patterns. The relevant statistical quantifiers are classically computable, define a falsifiable benchmark for BosonSampling, and reveal distinctive features of many-particle quantum dynamics, which go much beyond mere bunching or anti-bunching effects.

Robust multiperson tracking from a mobile platform.

PubMed

Ess, Andreas; Leibe, Bastian; Schindler, Konrad; van Gool, Luc

2009-10-01

In this paper, we address the problem of multiperson tracking in busy pedestrian zones using a stereo rig mounted on a mobile platform. The complexity of the problem calls for an integrated solution that extracts as much visual information as possible and combines it through cognitive feedback cycles. We propose such an approach, which jointly estimates camera position, stereo depth, object detection, and tracking. The interplay between those components is represented by a graphical model. Since the model has to incorporate object-object interactions and temporal links to past frames, direct inference is intractable. We, therefore, propose a two-stage procedure: for each frame, we first solve a simplified version of the model (disregarding interactions and temporal continuity) to estimate the scene geometry and an overcomplete set of object detections. Conditioned on these results, we then address object interactions, tracking, and prediction in a second step. The approach is experimentally evaluated on several long and difficult video sequences from busy inner-city locations. Our results show that the proposed integration makes it possible to deliver robust tracking performance in scenes of realistic complexity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koniges, A.E.; Craddock, G.G.; Schnack, D.D.

The purpose of the workshop was to assemble workers, both within and outside of the fusion-related computations areas, for discussion regarding the issues of dynamically adaptive gridding. There were three invited talks related to adaptive gridding application experiences in various related fields of computational fluid dynamics (CFD), and nine short talks reporting on the progress of adaptive techniques in the specific areas of scrape-off-layer (SOL) modeling and magnetohydrodynamic (MHD) stability. Adaptive mesh methods have been successful in a number of diverse fields of CFD for over a decade. The method involves dynamic refinement of computed field profiles in a waymore » that disperses uniformly the numerical errors associated with discrete approximations. Because the process optimizes computational effort, adaptive mesh methods can be used to study otherwise the intractable physical problems that involve complex boundary shapes or multiple spatial/temporal scales. Recent results indicate that these adaptive techniques will be required for tokamak fluid-based simulations involving the diverted tokamak SOL modeling and MHD simulations problems related to the highest priority ITER relevant issues.Individual papers are indexed separately on the energy data bases.« less

Cough Hypersensitivity Syndrome: A Few More Steps Forward

PubMed Central

Song, Woo-Jung

2017-01-01

Cough reflex is a vital protective mechanism against aspiration, but when dysregulated, it can become hypersensitive. In fact, chronic cough is a significant medical problem with a high degree of morbidity. Recently, a unifying paradigm of cough hypersensitivity syndrome has been proposed. It represents a clinical entity in which chronic cough is a major presenting problem, regardless of the underlying condition. Although it remains a theoretical construct, emerging evidence suggests that aberrant neurophysiology is the common etiology of this syndrome. Recent success in randomized clinical trials using a P2X3 receptor antagonist is the first major advance in the therapeutics of cough in the past 30 years; it at last provides a strategy for treating intractable cough as well as an invaluable tool for dissecting the mechanism underpinning cough hypersensitivity. Additionally, several cough measurement tools have been validated for use and will help assess the clinical relevance of cough in various underlying conditions. Along with this paradigm shift, our understanding of cough mechanisms has improved during the past decades, allowing us to continue to take more steps forward in the future. PMID:28677352

An approximate stationary solution for multi-allele neutral diffusion with low mutation rates.

PubMed

Burden, Conrad J; Tang, Yurong

2016-12-01

We address the problem of determining the stationary distribution of the multi-allelic, neutral-evolution Wright-Fisher model in the diffusion limit. A full solution to this problem for an arbitrary K×K mutation rate matrix involves solving for the stationary solution of a forward Kolmogorov equation over a (K-1)-dimensional simplex, and remains intractable. In most practical situations mutations rates are slow on the scale of the diffusion limit and the solution is heavily concentrated on the corners and edges of the simplex. In this paper we present a practical approximate solution for slow mutation rates in the form of a set of line densities along the edges of the simplex. The method of solution relies on parameterising the general non-reversible rate matrix as the sum of a reversible part and a set of (K-1)(K-2)/2 independent terms corresponding to fluxes of probability along closed paths around faces of the simplex. The solution is potentially a first step in estimating non-reversible evolutionary rate matrices from observed allele frequency spectra. Copyright © 2016 Elsevier Inc. All rights reserved.

Resolvent analysis of shear flows using One-Way Navier-Stokes equations

NASA Astrophysics Data System (ADS)

Rigas, Georgios; Schmidt, Oliver; Towne, Aaron; Colonius, Tim

2017-11-01

For three-dimensional flows, questions of stability, receptivity, secondary flows, and coherent structures require the solution of large partial-derivative eigenvalue problems. Reduced-order approximations are thus required for engineering prediction since these problems are often computationally intractable or prohibitively expensive. For spatially slowly evolving flows, such as jets and boundary layers, the One-Way Navier-Stokes (OWNS) equations permit a fast spatial marching procedure that results in a huge reduction in computational cost. Here, an adjoint-based optimization framework is proposed and demonstrated for calculating optimal boundary conditions and optimal volumetric forcing. The corresponding optimal response modes are validated against modes obtained in terms of global resolvent analysis. For laminar base flows, the optimal modes reveal modal and non-modal transition mechanisms. For turbulent base flows, they predict the evolution of coherent structures in a statistical sense. Results from the application of the method to three-dimensional laminar wall-bounded flows and turbulent jets will be presented. This research was supported by the Office of Naval Research (N00014-16-1-2445) and Boeing Company (CT-BA-GTA-1).

Modeling and deadlock avoidance of automated manufacturing systems with multiple automated guided vehicles.

PubMed

Wu, Naiqi; Zhou, MengChu

2005-12-01

An automated manufacturing system (AMS) contains a number of versatile machines (or workstations), buffers, an automated material handling system (MHS), and is computer-controlled. An effective and flexible alternative for implementing MHS is to use automated guided vehicle (AGV) system. The deadlock issue in AMS is very important in its operation and has extensively been studied. The deadlock problems were separately treated for parts in production and transportation and many techniques were developed for each problem. However, such treatment does not take the advantage of the flexibility offered by multiple AGVs. In general, it is intractable to obtain maximally permissive control policy for either problem. Instead, this paper investigates these two problems in an integrated way. First we model an AGV system and part processing processes by resource-oriented Petri nets, respectively. Then the two models are integrated by using macro transitions. Based on the combined model, a novel control policy for deadlock avoidance is proposed. It is shown to be maximally permissive with computational complexity of O (n2) where n is the number of machines in AMS if the complexity for controlling the part transportation by AGVs is not considered. Thus, the complexity of deadlock avoidance for the whole system is bounded by the complexity in controlling the AGV system. An illustrative example shows its application and power.

Biologically-inspired approaches for self-organization, adaptation, and collaboration of heterogeneous autonomous systems

NASA Astrophysics Data System (ADS)

Steinberg, Marc

2011-06-01

This paper presents a selective survey of theoretical and experimental progress in the development of biologicallyinspired approaches for complex surveillance and reconnaissance problems with multiple, heterogeneous autonomous systems. The focus is on approaches that may address ISR problems that can quickly become mathematically intractable or otherwise impractical to implement using traditional optimization techniques as the size and complexity of the problem is increased. These problems require dealing with complex spatiotemporal objectives and constraints at a variety of levels from motion planning to task allocation. There is also a need to ensure solutions are reliable and robust to uncertainty and communications limitations. First, the paper will provide a short introduction to the current state of relevant biological research as relates to collective animal behavior. Second, the paper will describe research on largely decentralized, reactive, or swarm approaches that have been inspired by biological phenomena such as schools of fish, flocks of birds, ant colonies, and insect swarms. Next, the paper will discuss approaches towards more complex organizational and cooperative mechanisms in team and coalition behaviors in order to provide mission coverage of large, complex areas. Relevant team behavior may be derived from recent advances in understanding of the social and cooperative behaviors used for collaboration by tens of animals with higher-level cognitive abilities such as mammals and birds. Finally, the paper will briefly discuss challenges involved in user interaction with these types of systems.

Learning of state-space models with highly informative observations: A tempered sequential Monte Carlo solution

NASA Astrophysics Data System (ADS)

Svensson, Andreas; Schön, Thomas B.; Lindsten, Fredrik

2018-05-01

Probabilistic (or Bayesian) modeling and learning offers interesting possibilities for systematic representation of uncertainty using probability theory. However, probabilistic learning often leads to computationally challenging problems. Some problems of this type that were previously intractable can now be solved on standard personal computers thanks to recent advances in Monte Carlo methods. In particular, for learning of unknown parameters in nonlinear state-space models, methods based on the particle filter (a Monte Carlo method) have proven very useful. A notoriously challenging problem, however, still occurs when the observations in the state-space model are highly informative, i.e. when there is very little or no measurement noise present, relative to the amount of process noise. The particle filter will then struggle in estimating one of the basic components for probabilistic learning, namely the likelihood p (data | parameters). To this end we suggest an algorithm which initially assumes that there is substantial amount of artificial measurement noise present. The variance of this noise is sequentially decreased in an adaptive fashion such that we, in the end, recover the original problem or possibly a very close approximation of it. The main component in our algorithm is a sequential Monte Carlo (SMC) sampler, which gives our proposed method a clear resemblance to the SMC2 method. Another natural link is also made to the ideas underlying the approximate Bayesian computation (ABC). We illustrate it with numerical examples, and in particular show promising results for a challenging Wiener-Hammerstein benchmark problem.

Developing the Young Gifted Child's Mathematical Mind

ERIC Educational Resources Information Center

Fisher, Carol

2016-01-01

Schools seem firmly rooted in the emphasis on computational mastery, and seldom seem to have time to develop other areas of mathematical thinking, such as real-world problem solving and the application of mathematical concepts. All too often, children seem to do well in math in the early grades because they easily memorize the facts and the…

The fitting of general force-of-infection models to wildlife disease prevalence data

USGS Publications Warehouse

Heisey, D.M.; Joly, D.O.; Messier, F.

2006-01-01

Researchers and wildlife managers increasingly find themselves in situations where they must deal with infectious wildlife diseases such as chronic wasting disease, brucellosis, tuberculosis, and West Nile virus. Managers are often charged with designing and implementing control strategies, and researchers often seek to determine factors that influence and control the disease process. All of these activities require the ability to measure some indication of a disease's foothold in a population and evaluate factors affecting that foothold. The most common type of data available to managers and researchers is apparent prevalence data. Apparent disease prevalence, the proportion of animals in a sample that are positive for the disease, might seem like a natural measure of disease's foothold, but several properties, in particular, its dependency on age structure and the biasing effects of disease-associated mortality, make it less than ideal. In quantitative epidemiology, the a??force of infection,a?? or infection hazard, is generally the preferred parameter for measuring a disease's foothold, and it can be viewed as the most appropriate way to a??adjusta?? apparent prevalence for age structure. The typical ecology curriculum includes little exposure to quantitative epidemiological concepts such as cumulative incidence, apparent prevalence, and the force of infection. The goal of this paper is to present these basic epidemiological concepts and resulting models in an ecological context and to illustrate how they can be applied to understand and address basic epidemiological questions. We demonstrate a practical approach to solving the heretofore intractable problem of fitting general force-of-infection models to wildlife prevalence data using a generalized regression approach. We apply the procedures to Mycobacterium bovis (bovine tuberculosis) prevalence in bison (Bison bison) in Wood Buffalo National Park, Canada, and demonstrate strong age dependency in the force of infection as well as an increased mortality hazard in positive animals.

Understanding Patients' Process to Use Medical Marijuana: A Southern New Jersey Community Engagement Project.

PubMed

Crowell, Tara L

2016-09-01

Given the necessity to better understand the process patients need to go through in order to seek treatment via medical marijuana, this study investigates this process to better understand this phenomenon. Specifically, Compassion Care Foundation (CCF) and Stockton University worked together to identify a solution to this problem. Specifically, 240 new patients at CCF were asked to complete a 1-page survey regarding various aspects associated with their experience prior to their use of medicinal marijuana-diagnosis, what prompted them to seek treatment, level of satisfaction with specific stages in the process, total length of time the process took, and patient's level of pain. Results reveal numerous patient diagnoses for which medical marijuana is being prescribed; the top 4 most common are intractable skeletal spasticity, chronic and severe pain, multiple sclerosis, and inflammatory bowel disease. Next, results indicate a little over half of the patients were first prompted to seek alternative treatment from their physicians, while the remaining patients indicated that other sources such as written information along with friends, relatives, media, and the Internet persuaded them to seek treatment. These data indicate that a variety of sources play a role in prompting patients to seek alternative treatment and is a critical first step in this process. Additional results posit that once patients began the process of qualifying to receive medical marijuana as treatment, the process seemed more positive even though it takes patients on average almost 6 months to obtain their first treatment after they started the process. Finally, results indicate that patients are reporting a moderately high level of pain prior to treatment. Implication of these results highlights several important elements in the patients' initial steps toward seeking medical marijuana, along with the quality and quantity of the process patients must engage in prior to obtaining treatment. In addition, identifying patients' level of pain and better understanding the possible therapeutic value of medical marijuana are essential to patients and health practitioners.

An electromechanical Ising Hamiltonian

PubMed Central

Mahboob, Imran; Okamoto, Hajime; Yamaguchi, Hiroshi

2016-01-01

Solving intractable mathematical problems in simulators composed of atoms, ions, photons, or electrons has recently emerged as a subject of intense interest. We extend this concept to phonons that are localized in spectrally pure resonances in an electromechanical system that enables their interactions to be exquisitely fashioned via electrical means. We harness this platform to emulate the Ising Hamiltonian whose spin 1/2 particles are replicated by the phase bistable vibrations from the parametric resonances of multiple modes. The coupling between the mechanical spins is created by generating two-mode squeezed states, which impart correlations between modes that can imitate a random, ferromagnetic state or an antiferromagnetic state on demand. These results suggest that an electromechanical simulator could be built for the Ising Hamiltonian in a nontrivial configuration, namely, for a large number of spins with multiple degrees of coupling. PMID:28861469

An electromechanical Ising Hamiltonian.

PubMed

Mahboob, Imran; Okamoto, Hajime; Yamaguchi, Hiroshi

2016-06-01

Solving intractable mathematical problems in simulators composed of atoms, ions, photons, or electrons has recently emerged as a subject of intense interest. We extend this concept to phonons that are localized in spectrally pure resonances in an electromechanical system that enables their interactions to be exquisitely fashioned via electrical means. We harness this platform to emulate the Ising Hamiltonian whose spin 1/2 particles are replicated by the phase bistable vibrations from the parametric resonances of multiple modes. The coupling between the mechanical spins is created by generating two-mode squeezed states, which impart correlations between modes that can imitate a random, ferromagnetic state or an antiferromagnetic state on demand. These results suggest that an electromechanical simulator could be built for the Ising Hamiltonian in a nontrivial configuration, namely, for a large number of spins with multiple degrees of coupling.

Virtual local target method for avoiding local minimum in potential field based robot navigation.

PubMed

Zou, Xi-Yong; Zhu, Jing

2003-01-01

A novel robot navigation algorithm with global path generation capability is presented. Local minimum is a most intractable but is an encountered frequently problem in potential field based robot navigation. Through appointing appropriately some virtual local targets on the journey, it can be solved effectively. The key concept employed in this algorithm are the rules that govern when and how to appoint these virtual local targets. When the robot finds itself in danger of local minimum, a virtual local target is appointed to replace the global goal temporarily according to the rules. After the virtual target is reached, the robot continues on its journey by heading towards the global goal. The algorithm prevents the robot from running into local minima anymore. Simulation results showed that it is very effective in complex obstacle environments.

Ubiquitous Robotic Technology for Smart Manufacturing System.

PubMed

Wang, Wenshan; Zhu, Xiaoxiao; Wang, Liyu; Qiu, Qiang; Cao, Qixin

2016-01-01

As the manufacturing tasks become more individualized and more flexible, the machines in smart factory are required to do variable tasks collaboratively without reprogramming. This paper for the first time discusses the similarity between smart manufacturing systems and the ubiquitous robotic systems and makes an effort on deploying ubiquitous robotic technology to the smart factory. Specifically, a component based framework is proposed in order to enable the communication and cooperation of the heterogeneous robotic devices. Further, compared to the service robotic domain, the smart manufacturing systems are often in larger size. So a hierarchical planning method was implemented to improve the planning efficiency. A test bed of smart factory is developed. It demonstrates that the proposed framework is suitable for industrial domain, and the hierarchical planning method is able to solve large problems intractable with flat methods.

Ubiquitous Robotic Technology for Smart Manufacturing System

PubMed Central

Zhu, Xiaoxiao; Wang, Liyu; Qiu, Qiang; Cao, Qixin

2016-01-01

As the manufacturing tasks become more individualized and more flexible, the machines in smart factory are required to do variable tasks collaboratively without reprogramming. This paper for the first time discusses the similarity between smart manufacturing systems and the ubiquitous robotic systems and makes an effort on deploying ubiquitous robotic technology to the smart factory. Specifically, a component based framework is proposed in order to enable the communication and cooperation of the heterogeneous robotic devices. Further, compared to the service robotic domain, the smart manufacturing systems are often in larger size. So a hierarchical planning method was implemented to improve the planning efficiency. A test bed of smart factory is developed. It demonstrates that the proposed framework is suitable for industrial domain, and the hierarchical planning method is able to solve large problems intractable with flat methods. PMID:27446206

Explicit integration with GPU acceleration for large kinetic networks

DOE PAGES

Brock, Benjamin; Belt, Andrew; Billings, Jay Jay; ...

2015-09-15

In this study, we demonstrate the first implementation of recently-developed fast explicit kinetic integration algorithms on modern graphics processing unit (GPU) accelerators. Taking as a generic test case a Type Ia supernova explosion with an extremely stiff thermonuclear network having 150 isotopic species and 1604 reactions coupled to hydrodynamics using operator splitting, we demonstrate the capability to solve of order 100 realistic kinetic networks in parallel in the same time that standard implicit methods can solve a single such network on a CPU. In addition, this orders-of-magnitude decrease in computation time for solving systems of realistic kinetic networks implies thatmore » important coupled, multiphysics problems in various scientific and technical fields that were intractable, or could be simulated only with highly schematic kinetic networks, are now computationally feasible.« less

Introduction to cryogenic wind tunnels

NASA Technical Reports Server (NTRS)

Goodyer, M. J.

1985-01-01

The background to the evolution of the cryogenic wind tunnel is outlined, with particular reference to the late 60's/early 70's when efforts were begun to re-equip with larger wind tunnels. The problems of providing full scale Reynolds numbers in transonic testing were proving particularly intractible, when the notion of satisfying the needs with the cryogenic tunnel was proposed, and then adopted. The principles and advantages of the cryogenic tunnel are outlined, along with guidance on the coolant needs when this is liquid nitrogen, and with a note on energy recovery. Operational features of the tunnels are introduced with reference to a small low speed tunnel. Finally the outstanding contributions are highlighted of the 0.3-Meter Transonic Cryogenic Tunnel (TCT) at NASA Langley Research Center, and its personnel, to the furtherance of knowledge and confidence in the concept.

Social Norms and Global Environmental Challenges: The Complex Interaction of Behaviors, Values, and Policy

PubMed Central

Ehrlich, Paul R.; Alston, Lee J.; Arrow, Kenneth; Barrett, Scott; Buchman, Timothy G.; Daily, Gretchen C.; Levin, Bruce; Levin, Simon; Oppenheimer, Michael; Ostrom, Elinor; Saari, Donald

2014-01-01

SUMMARY Government policies are needed when people’s behaviors fail to deliver the public good. Those policies will be most effective if they can stimulate long-term changes in beliefs and norms, creating and reinforcing the behaviors needed to solidify and extend the public good.It is often the short-term acceptability of potential policies, rather than their longer-term efficacy, that determines their scope and deployment. The policy process should consider both time scales. The academy, however, has provided insufficient insight on the coevolution of social norms and different policy instruments, thus compromising the capacity of decision makers to craft effective solutions to the society’s most intractable environmental problems. Life scientists could make fundamental contributions to this agenda through targeted research on the emergence of social norms. PMID:25143635

Witnessing eigenstates for quantum simulation of Hamiltonian spectra

PubMed Central

Santagati, Raffaele; Wang, Jianwei; Gentile, Antonio A.; Paesani, Stefano; Wiebe, Nathan; McClean, Jarrod R.; Morley-Short, Sam; Shadbolt, Peter J.; Bonneau, Damien; Silverstone, Joshua W.; Tew, David P.; Zhou, Xiaoqi; O’Brien, Jeremy L.; Thompson, Mark G.

2018-01-01

The efficient calculation of Hamiltonian spectra, a problem often intractable on classical machines, can find application in many fields, from physics to chemistry. We introduce the concept of an “eigenstate witness” and, through it, provide a new quantum approach that combines variational methods and phase estimation to approximate eigenvalues for both ground and excited states. This protocol is experimentally verified on a programmable silicon quantum photonic chip, a mass-manufacturable platform, which embeds entangled state generation, arbitrary controlled unitary operations, and projective measurements. Both ground and excited states are experimentally found with fidelities >99%, and their eigenvalues are estimated with 32 bits of precision. We also investigate and discuss the scalability of the approach and study its performance through numerical simulations of more complex Hamiltonians. This result shows promising progress toward quantum chemistry on quantum computers. PMID:29387796

Modeling the Mousetrap Car

NASA Astrophysics Data System (ADS)

Jumper, William D.

2012-03-01

Many high school and introductory college physics courses make use of mousetrap car projects and competitions as a way of providing an engaging hands-on learning experience incorporating Newton's laws, conversion of potential to kinetic energy, dissipative forces, and rotational mechanics. Presented here is a simple analytical and finite element spreadsheet model for a typical mousetrap car, as shown in Fig. 1. It is hoped that the model will provide students with a tool for designing or modifying the designs of their cars, provide instructors with a means to insure students close the loop between physical principles and an understanding of their car's speed and distance performance, and, third, stimulate in students at an early stage an appreciation for the merits of computer modeling as an aid in understanding and tackling otherwise analytically intractable problems so common in today's professional world.

Plotting equation for gaussian percentiles and a spreadsheet program for generating probability plots

USGS Publications Warehouse

Balsillie, J.H.; Donoghue, J.F.; Butler, K.M.; Koch, J.L.

2002-01-01

Two-dimensional plotting tools can be of invaluable assistance in analytical scientific pursuits, and have been widely used in the analysis and interpretation of sedimentologic data. We consider, in this work, the use of arithmetic probability paper (APP). Most statistical computer applications do not allow for the generation of APP plots, because of apparent intractable nonlinearity of the percentile (or probability) axis of the plot. We have solved this problem by identifying an equation(s) for determining plotting positions of Gaussian percentiles (or probabilities), so that APP plots can easily be computer generated. An EXCEL example is presented, and a programmed, simple-to-use EXCEL application template is hereby made publicly available, whereby a complete granulometric analysis including data listing, moment measure calculations, and frequency and cumulative APP plots, is automatically produced.

A Scheme to Optimize Flow Routing and Polling Switch Selection of Software Defined Networks

PubMed Central

Chen, Huan; Li, Lemin; Ren, Jing; Wang, Yang; Zhao, Yangming; Wang, Xiong; Wang, Sheng; Xu, Shizhong

2015-01-01

This paper aims at minimizing the communication cost for collecting flow information in Software Defined Networks (SDN). Since flow-based information collecting method requires too much communication cost, and switch-based method proposed recently cannot benefit from controlling flow routing, jointly optimize flow routing and polling switch selection is proposed to reduce the communication cost. To this end, joint optimization problem is formulated as an Integer Linear Programming (ILP) model firstly. Since the ILP model is intractable in large size network, we also design an optimal algorithm for the multi-rooted tree topology and an efficient heuristic algorithm for general topology. According to extensive simulations, it is found that our method can save up to 55.76% communication cost compared with the state-of-the-art switch-based scheme. PMID:26690571

A plea for rational mitigation of poor outcomes in the 'off-label use' of medications for the management of pain.

PubMed

Khursheed, Faraz; Ioffe, Julia; Gould, Harry J

2015-02-15

Neuropathic pain is a common and difficult to manage public health problem characterized by frequent treatment failure and high management costs. The variable presentation and response to treatment among patients make it difficult for physicians to apply a single, standardized approach for management. The physician's role in treating neuropathic pain is complex. Clinical decisions must be drawn from personal and shared experience, case reports, and evidence-based, controlled trials performed on selected populations of patients with common, narrowly-defined conditions. Recent advances in our understanding of the mechanisms that underlie the processing of nociceptive stimuli and the perception of pain have led to the increased 'off-label use' of adjuvant medications in an attempt to provide relief for many patients who heretofore have suffered unnecessarily with intractable neuropathic pain. Unfortunately, as with any treatment, sound clinical decisions can occasionally result in an untoward adverse response. It is therefore imperative that potential adverse effects inherent to all medications be considered and weighed against the untoward consequences of withholding treatment prior to incorporating their use in any course of management. This commentary presents a case report that illustrates a particularly devastating consequence that was encountered when a medication was selected for 'off-label use' in the treatment of intractable pain and presents an opinion for consideration in developing guidelines for determining acceptable risk and standard of care based upon rational adherence or deviation from the approved indications offered for the use of a medication at the time of its introduction into practice is granted. Copyright © 2014 Elsevier B.V. All rights reserved.

Clinical utility of the Wechsler Memory Scale - Fourth Edition (WMS-IV) in patients with intractable temporal lobe epilepsy.

PubMed

Bouman, Zita; Elhorst, Didi; Hendriks, Marc P H; Kessels, Roy P C; Aldenkamp, Albert P

2016-02-01

The Wechsler Memory Scale (WMS) is one of the most widely used test batteries to assess memory functions in patients with brain dysfunctions of different etiologies. This study examined the clinical validation of the Dutch Wechsler Memory Scale - Fourth Edition (WMS-IV-NL) in patients with temporal lobe epilepsy (TLE). The sample consisted of 75 patients with intractable TLE, who were eligible for epilepsy surgery, and 77 demographically matched healthy controls. All participants were examined with the WMS-IV-NL. Patients with TLE performed significantly worse than healthy controls on all WMS-IV-NL indices and subtests (p<.01), with the exception of the Visual Working Memory Index including its contributing subtests, as well as the subtests Logical Memory I, Verbal Paired Associates I, and Designs II. In addition, patients with mesiotemporal abnormalities performed significantly worse than patients with lateral temporal abnormalities on the subtests Logical Memory I and Designs II and all the indices (p<.05), with the exception of the Auditory Memory Index and Visual Working Memory Index. Patients with either a left or a right temporal focus performed equally on all WMS-IV-NL indices and subtests (F(15, 50)=.70, p=.78), as well as the Auditory-Visual discrepancy score (t(64)=-1.40, p=.17). The WMS-IV-NL is capable of detecting memory problems in patients with TLE, indicating that it is a sufficiently valid memory battery. Furthermore, the findings support previous research showing that the WMS-IV has limited value in identifying material-specific memory deficits in presurgical patients with TLE. Copyright © 2015 Elsevier Inc. All rights reserved.

CAMPways: constrained alignment framework for the comparative analysis of a pair of metabolic pathways.

PubMed

Abaka, Gamze; Bıyıkoğlu, Türker; Erten, Cesim

2013-07-01

Given a pair of metabolic pathways, an alignment of the pathways corresponds to a mapping between similar substructures of the pair. Successful alignments may provide useful applications in phylogenetic tree reconstruction, drug design and overall may enhance our understanding of cellular metabolism. We consider the problem of providing one-to-many alignments of reactions in a pair of metabolic pathways. We first provide a constrained alignment framework applicable to the problem. We show that the constrained alignment problem even in a primitive setting is computationally intractable, which justifies efforts for designing efficient heuristics. We present our Constrained Alignment of Metabolic Pathways (CAMPways) algorithm designed for this purpose. Through extensive experiments involving a large pathway database, we demonstrate that when compared with a state-of-the-art alternative, the CAMPways algorithm provides better alignment results on metabolic networks as far as measures based on same-pathway inclusion and biochemical significance are concerned. The execution speed of our algorithm constitutes yet another important improvement over alternative algorithms. Open source codes, executable binary, useful scripts, all the experimental data and the results are freely available as part of the Supplementary Material at http://code.google.com/p/campways/. Supplementary data are available at Bioinformatics online.

Optimizing spread dynamics on graphs by message passing

NASA Astrophysics Data System (ADS)

Altarelli, F.; Braunstein, A.; Dall'Asta, L.; Zecchina, R.

2013-09-01

Cascade processes are responsible for many important phenomena in natural and social sciences. Simple models of irreversible dynamics on graphs, in which nodes activate depending on the state of their neighbors, have been successfully applied to describe cascades in a large variety of contexts. Over the past decades, much effort has been devoted to understanding the typical behavior of the cascades arising from initial conditions extracted at random from some given ensemble. However, the problem of optimizing the trajectory of the system, i.e. of identifying appropriate initial conditions to maximize (or minimize) the final number of active nodes, is still considered to be practically intractable, with the only exception being models that satisfy a sort of diminishing returns property called submodularity. Submodular models can be approximately solved by means of greedy strategies, but by definition they lack cooperative characteristics which are fundamental in many real systems. Here we introduce an efficient algorithm based on statistical physics for the optimization of trajectories in cascade processes on graphs. We show that for a wide class of irreversible dynamics, even in the absence of submodularity, the spread optimization problem can be solved efficiently on large networks. Analytic and algorithmic results on random graphs are complemented by the solution of the spread maximization problem on a real-world network (the Epinions consumer reviews network).

Generalized Buneman Pruning for Inferring the Most Parsimonious Multi-state Phylogeny

NASA Astrophysics Data System (ADS)

Misra, Navodit; Blelloch, Guy; Ravi, R.; Schwartz, Russell

Accurate reconstruction of phylogenies remains a key challenge in evolutionary biology. Most biologically plausible formulations of the problem are formally NP-hard, with no known efficient solution. The standard in practice are fast heuristic methods that are empirically known to work very well in general, but can yield results arbitrarily far from optimal. Practical exact methods, which yield exponential worst-case running times but generally much better times in practice, provide an important alternative. We report progress in this direction by introducing a provably optimal method for the weighted multi-state maximum parsimony phylogeny problem. The method is based on generalizing the notion of the Buneman graph, a construction key to efficient exact methods for binary sequences, so as to apply to sequences with arbitrary finite numbers of states with arbitrary state transition weights. We implement an integer linear programming (ILP) method for the multi-state problem using this generalized Buneman graph and demonstrate that the resulting method is able to solve data sets that are intractable by prior exact methods in run times comparable with popular heuristics. Our work provides the first method for provably optimal maximum parsimony phylogeny inference that is practical for multi-state data sets of more than a few characters.

Microencephaloceles: another dual pathology of intractable temporal lobe epilepsy in childhood.

PubMed

Aquilina, Kristian; Clarke, Dave F; Wheless, James W; Boop, Frederick A

2010-04-01

Temporal lobe encephaloceles can be associated with temporal lobe epilepsy. The authors report on the case of an adolescent with multiple microencephaloceles, in the anterolateral middle fossa floor, identified at surgery (temporal lobectomy) for intractable partial-onset seizures of temporal origin. Magnetic resonance imaging revealed only hippocampal atrophy. Subdural electrodes demonstrated ictal activity arising primarily from the anterior and lateral temporal lobe, close to the microencephaloceles, spreading to the anterior and posterior mesial structures. Pathological examination revealed diffuse temporal gliosis involving the hippocampus, together with microdysgenesis of the amygdala. The literature on epilepsy secondary to encephaloceles is reviewed and the contribution of the microencephaloceles to the seizure disorder in this patient is discussed.

The patient had a normal magnetic resonance imaging and temporal lobe epilepsy secondary to a porencephalic cyst but showed structural lesions (hippocampal sclerosis)☆

PubMed Central

Matsubara, Teppei; Ayuzawa, Satoshi; Aoki, Tsukasa; Fujiomto, Ayataka; Osuka, Satoru; Matsumura, Akira

2013-01-01

Patients with a porencephalic cyst frequently develop intractable temporal lobe epilepsy (TLE). We report a surgically-treated male patient with intractable mesial TLE (mTLE) secondary to a porencephalic cyst. Although magnetic resonance imaging showed no hippocampal abnormalities, long-term video-electrocorticography revealed seizure onset discharges in the hippocampus. Temporal lobectomy brought an end to the patient's seizures. Hippocampal sclerosis was histopathologically confirmed (dual pathology). Careful evaluation of hippocampal epileptogenicity is required, and temporal lobectomy, which is less invasive than hemispherectomy, can be a treatment of choice for patients with mTLE secondary to a porencephalic cyst. PMID:25667851

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Nicholas, E-mail: nibrown@cantab.net; Olayos, Elizabeth; Elmer, Sandra

Management of intractable haematuria and obstructive urosepsis from upper tract urothelial carcinoma can be problematic in patients not suitable for surgery, chemotherapy or radiotherapy. Interventional radiology techniques provide alternative approaches in this setting, such as complete kidney embolization to cease urine output, percutaneous nephrostomy, antegrade injection of sclerotherapy agents and sterilisation of the upper collecting system. Related approaches have been successfully employed to sclerose renal cysts, lymphoceles, chyluria and intractable lower tract haemorrhage. No reports of percutaneous, antegrade sclerotherapy in the upper urinary tract have previously been published. We present a case of recurrent haematuria and obstructive urosepsis caused bymore » invasive upper tract urothelial carcinoma in a non-operative patient, which was treated with renal embolisation and percutaneous upper tract urothelial sclerotherapy.« less

Intradural approach to selective stimulation in the spinal cord for treatment of intractable pain: design principles and wireless protocol

NASA Astrophysics Data System (ADS)

Howard, M. A.; Utz, M.; Brennan, T. J.; Dalm, B. D.; Viljoen, S.; Jeffery, N. D.; Gillies, G. T.

2011-08-01

We introduce an intradural approach to spinal cord stimulation for the relief of intractable pain, and describe the biophysical rationale that underlies its design and performance requirements. The proposed device relies on wireless, inductive coupling between a pial surface implant and its epidural controller, and we present the results of benchtop experiments that demonstrate the ability to transmit and receive a frequency-modulated 1.6 MHz carrier signal between micro-coil antennae scaled to the ≈ 1 cm dimensions of the implant, at power levels of about 5 mW. Plans for materials selection, microfabrication, and other aspects of future development are presented and discussed.

Variational Bayesian Learning for Wavelet Independent Component Analysis

NASA Astrophysics Data System (ADS)

Roussos, E.; Roberts, S.; Daubechies, I.

2005-11-01

In an exploratory approach to data analysis, it is often useful to consider the observations as generated from a set of latent generators or "sources" via a generally unknown mapping. For the noisy overcomplete case, where we have more sources than observations, the problem becomes extremely ill-posed. Solutions to such inverse problems can, in many cases, be achieved by incorporating prior knowledge about the problem, captured in the form of constraints. This setting is a natural candidate for the application of the Bayesian methodology, allowing us to incorporate "soft" constraints in a natural manner. The work described in this paper is mainly driven by problems in functional magnetic resonance imaging of the brain, for the neuro-scientific goal of extracting relevant "maps" from the data. This can be stated as a `blind' source separation problem. Recent experiments in the field of neuroscience show that these maps are sparse, in some appropriate sense. The separation problem can be solved by independent component analysis (ICA), viewed as a technique for seeking sparse components, assuming appropriate distributions for the sources. We derive a hybrid wavelet-ICA model, transforming the signals into a domain where the modeling assumption of sparsity of the coefficients with respect to a dictionary is natural. We follow a graphical modeling formalism, viewing ICA as a probabilistic generative model. We use hierarchical source and mixing models and apply Bayesian inference to the problem. This allows us to perform model selection in order to infer the complexity of the representation, as well as automatic denoising. Since exact inference and learning in such a model is intractable, we follow a variational Bayesian mean-field approach in the conjugate-exponential family of distributions, for efficient unsupervised learning in multi-dimensional settings. The performance of the proposed algorithm is demonstrated on some representative experiments.

Etanercept overcomes P-glycoprotein-induced drug resistance in lymphocytes of patients with intractable rheumatoid arthritis.

PubMed

Tsujimura, Shizuyo; Saito, Kazuyoshi; Nakayamada, Shingo; Tanaka, Yoshiya

2010-04-01

P-glycoprotein (P-gp) on activated lymphocytes is an adenosine triphosphate (ATP)-binding cassette transporter that causes drug resistance by exclusion of intracellular drugs in patients with active rheumatoid arthritis (RA). However, infliximab with methotrexate (MTX) can overcome P-gp-mediated drug resistance. We encounter patients who cannot continue infliximab or MTX. Here we tested how etanercept affected P-gp-mediated drug resistance in such intractable RA patients. Peripheral lymphocytes of 11 RA patients (3 switched from infliximab and 8 who could not be treated with MTX) were analyzed for P-gp expression by flow cytometry and for drug exclusion using radioisotope-labeled dexamethasone. Activated lymphocytes of RA patients overexpressed P-gp and coexpressed CD69. Incubation of these lymphocytes with dexamethasone in vitro reduced intracellular dexamethasone levels. Two-week etanercept therapy significantly reduced P-gp expression and eliminated such P-gp- and CD69-high-expressing subgroup. The reduction in P-gp resulted in recovery of intracellular dexamethasone levels in lymphocytes and improvement of disease activity, thus allowing tapering of corticosteroids. None of the patients experienced any severe adverse effects. Etanercept is useful for overcoming P-gp-mediated treatment resistance in intractable RA patients who have to discontinue infliximab or are intolerant to MTX.

Ahmed glaucoma valve in eyes with preexisting episcleral encircling element.

PubMed

Choudhari, Nikhil Shreeram; George, Ronnie; Shantha, Balekudaru; Neog, Aditya; Tripathi, Shweta; Srinivasan, Bhaskar; Vijaya, Lingam

2014-05-01

To describe the use of Ahmed glaucoma valve (AGV) in the management of intractable glaucoma in eyes with a preexisting episcleral encircling element. This is a retrospective, consecutive, noncomparative study. The study included 12 eyes of 12 patients with a preexisting episcleral encircling element that underwent implantation of silicone AGV to treat intractable glaucoma during January 2009 to September 2010. The mean patient age was 25.6 (standard deviation 17.1) years. Five (41.6%) patients were monocular. The indications for AGV were varied. The mean duration between placement of episcleral encircling element and implantation of AGV was 30.5 (33.8) months. The mean follow-up was 37.4 (22.9) weeks. Preoperatively, the mean intraocular pressure (IOP) was 31.4 (7.9) mmHg and the mean antiglaucoma medications were 2.8. At the final postoperative follow-up, the mean IOP was 12.5 (3.5) mmHg and the mean number of antiglaucoma medications was 0.8 (P < 0.001). The complications observed over the follow-up period did include corneal graft failure in three eyes, tube erosion in two eyes and rhegmatogenous retinal detachment in one eye. AGV is an effective option in the management of intractable glaucoma in eyes with a preexisting episcleral encircling element keeping in mind the possibility of significant postoperative complications.

The role of executive functioning in quality of life in pediatric intractable epilepsy.

PubMed

Love, Christina Eguizabal; Webbe, Frank; Kim, Gunha; Lee, Ki Hyeong; Westerveld, Michael; Salinas, Christine M

2016-11-01

Children with epilepsy are vulnerable to executive dysfunction, but the relationship between executive functioning (EF) and quality of life (QOL) in children with epilepsy is not fully delineated. This exploratory study elucidated the relationship between ecological EF and QOL in pediatric intractable epilepsy. Fifty-four consecutively referred pediatric epilepsy surgery candidates and their parents were administered IQ measures, the Behavior Rating Inventory of Executive Function (BRIEF), and the Quality of Life in Childhood Epilepsy (QOLCE) as part of a comprehensive neuropsychological evaluation. A significant difference was found in QOL between those with and without clinical impairments on the BRIEF [t(52)=3.93; p<.001]. That is, children with executive dysfunction had lower overall QOL. All seizure variables and BRIEF scales were associated with overall QOL [F(12, 40)=6.508; p=.001; R 2 =.661]. Working memory from the BRIEF was the most frequently elevated scale in our sample (57%). Those with executive dysfunction had 9.7 times the risk of having poor QOL. Poor EF control according to behavior ratings is significantly related to QOL in intractable pediatric epilepsy. Identification of executive dysfunction in home environments is an essential component of presurgical evaluations and target for intervention, which may improve QOL. Copyright © 2016 Elsevier Inc. All rights reserved.

Combined ultrasound and fluoroscopic guidance for radiofrequency ablation of the obturator nerve for intractable cancer-associated hip pain.

PubMed

Stone, Jonathan; Matchett, Gerald

2014-01-01

Management of pain from skeletal metastases is notoriously difficult. Case reports and case series have described radiofrequency ablation of the obturator nerve branches to the femoral head for treatment of intractable hip pain. Ablation of the obturator branches to the femoral head is technically difficult because of bony and vascular anatomy, including close proximity of the femoral vessels. Here we present the case of a 79-year-old woman with intractable right hip pain and inability to ambulate secondary to metastatic non-small cell lung cancer in the femoral head and acetabulum, treated with thermal radiofrequency ablation of the obturator and femoral nerve branches to the femoral head. Ablation of the obturator nerve was done via anterior placement of the radiofrequency needle under combined ultrasound and fluoroscopic guidance, passing the radiofrequency needle between the femoral artery and femoral vein. Real-time ultrasound guidance was used to avoid vascular puncture. Thermal radiofrequency ablation resulted in sustained pain relief, and resumption in the ability of the patient to ambulate. From this case we suggest that an anterior approach to the obturator nerve branches to the femoral head may be technically feasible using combined ultrasound and fluoroscopic guidance to avoid vascular puncture.

Unfreezing cognitions during an intractable conflict: Does an external incentive for negotiating peace and (low levels of) collective angst increase information seeking?

PubMed

Wohl, Michael J A; Porat, Roni; Halperin, Eran

2016-03-01

A core feature of intractable conflicts is the tendency to cognitively freeze on existing, pro-ingroup beliefs. In three experiments, conducted in the context of the Palestinian-Israeli conflict, we tested the idea that an external incentive for negotiating peace helps unfreeze cognitions. In Experiment 1, making salient that peace with the Palestinians would reduce the Iranian nuclear threat (an external incentive) led to a process of unfreezing. In Experiment 2, we examined whether collective angst as an emotional sentiment (i.e., concern for the ingroup's future vitality as a temporally stable emotional disposition) moderated the aforementioned external incentive-cognitive unfreezing link. As predicted, external incentive salience promoted cognitive unfreezing, but only among people low in collective angst (i.e., people who are not concerned for the ingroup's future). In Experiment 3, we sought to replicate the results of Experiment 2. However, socio-political forces (i.e., a significant upswing in tensions between Palestinians and Israelis) likely served to freeze cognitions to such an extent that thawing was not possible by the means demonstrated in Experiments 1 and 2. The importance of confidence in a peace process is discussed in the context of efforts to unfreeze cognitions during an intractable conflict. © 2015 The British Psychological Society.

Relieving existential suffering through palliative sedation: discussion of an uneasy practice.

PubMed

Bruce, Anne; Boston, Patricia

2011-12-01

This article presents a discussion of the use of palliative sedation in response to intractable (not responsive to treatment) existential suffering. Patients suffering from a terminal illness are often faced with severe symptoms at the end of life. Although palliative sedation is sometimes used when no other options are effective in relieving unbearable pain or suffering, its use in response to intractable existential suffering in terminal illness remains controversial. A literature search was conducted for published articles addressing the use of palliative sedation between 1996 and 2009 using established databases. Palliative sedation remains an uneasy practice. The debates have centred on ethical issues surrounding decisions to use sedation and on separating the intent of palliative sedation (relief of intolerable symptoms) from the intent of euthanasia (hastening death). There is lack of consensus in defining existential suffering. Consequently, there is limited understanding of how decisions are being made when using palliative sedation to treat intractable existential suffering. Given the confusion and uncertainty about ethical and clinical justifications for palliative sedation in treating existential suffering, we argue that a better understanding of the controversies and decision-making process is needed. Greater understanding is required to prevent palliative sedation from becoming a substitute for intensive treatment of this kind of suffering. © 2011 Blackwell Publishing Ltd.

Evidence-Based Modification of Intratympanic Gentamicin Injections in Patients With Intractable Vertigo

PubMed Central

Zhai, Feng; Liu, Jian-Ping; Dai, Chun-Fu; Wang, Qi; Steyger, Peter S.

2013-01-01

Objectives To compare the cochlear distribution of low-dose fluorescent gentamicin after intra-tympanic administration in guinea pig (GPs) with clinical data of low dose intra-tympanic gentamicin in patients with intractable vertigo. Materials and Methods Purified gentamicin-Texas Red (GTTR) was injected intratympanically into GPs and the cochlear distribution and time course of GTTR fluorescence in outer hair cells (OHCs) was determined using confocal microscopy. Results GTTR was rapidly taken up by OHCs, particularly in the subcuticular zone. GTTR was distributed in the cochlea in a decreasing baso-apical gradient, and was retained within OHCs without significant decrease in fluorescence until 4 weeks after injection. Conclusion OHCs rapidly take up GTTR after intra-tympanic administration with slow clearance. Clinical Application A modified low-dose titration intratympanic approach was applied to patients with intractable Ménière’s Disease (MD) based on our animal data and the clinical outcome was followed. After the modified intratympanic injections for MD patients, vertigo control was achieved in 89% patients, with hearing deterioration identified in 16% patients. The 3-week interval titration injection technique thereby had a relatively high vertigo control rate with a low risk of hearing loss, and is a viable alternative to other intratympanic injection protocols. PMID:20393376

[Manegement and countermeasures against tuberculous patients with chronic positive sputum].

PubMed

Sato, K

1996-01-01

We studied measures for the prevention and treatment of chronic positive-sputum tuberculosis. Most physicians treating chronic intractable pulmonary tuberculosis are concerned about treatment and control measures. However, both the medical and social aspects of the disease must be dealt with. The study of the medical aspects of tuberculosis used data on patients at the Tokyo National Chest Hospital and other sanitoria in Japan. The socioeconomic study employed data from a health center in Tokyo. Recently, new cases of tuberculosis are concentrated in socioeconomically high risk groups, such as the homeless and illegal aliens, in a few large cities. Patients in these groups often have multidrug-resistant tuberculosis (MDRTB), including many patients with relapsing tuberculosis. However, it is dificult to keep such patients under treatment because of poor compliance and patient dropout. The results of our study are summarized as follows: 1. Prevention and treatment of chronic intractable tuberculosis should involve both the medical and socioeconomic aspects of the disease. 2. Surgical treatment offers benefits for patients with chronically positive sputum. Therefore, surgery should be recommended to patients with chronic intractable MDRTB. 3. If resistance to both isoniazid and rifampin is demonstrated, it is better to replace all ineffective drugs with a new effective regimen than to add a single drug to a failing regimen.

Successful treatment of a primary gastric plasmacytoma mimicking intractable gastric ulcer by using high-dose dexamethasone therapy: a case report.

PubMed

Kang, Da-yeong; Kim, Gee-Bum; Choi, Byung-Seok; Seo, Jun-won; Lim, Hyun-Jong; Hong, Ran; Park, Sang-Gon

2016-03-31

Extramedullary plasmacytoma is a plasma cell neoplasm that presents as a solitary lesion in soft tissue. Most extramedullary plasmacytomas involve the nasopharynx or upper respiratory tract. Primary plasmacytoma of the stomach is extremely rare. A 78-year-old Korean woman presented with epigastric pain for 3 months. She had a history of an intractable gastric ulcer despite repeated endoscopic biopsies and appropriate medical therapy for the ulcer. She underwent another endoscopy and a biopsy was performed for multiple large and deep specimens. Ultimately, primary gastric plasmacytoma was confirmed. However, she and her attendant refused standard local radiotherapy or surgical resection. She came to our emergency room 3 months later with hematemesis due to a large gastric ulcer, despite management with medication for over 3 months at a local clinic. We again recommended local radiation or surgical resection. However, as she was willing to undergo only medical therapy, she was prescribed high-dose dexamethasone. Surprisingly, her ulcer completely regressed and remission was maintained for over 1 year. We report successful treatment of a rare primary gastric plasmacytoma mimicking intractable ulcer by using high-dose dexamethasone. To the best of our knowledge, this is the first reported case successfully treated with only high-dose dexamethasone.

Primary non-Hodgkin’s lymphoma of the prostate with intractable hematuria: A case report and review of the literature

PubMed Central

HU, SHANBIAO; WANG, YINHUAI; YANG, LUOYAN; YI, LU; NIAN, YEQI

2015-01-01

Cases of primary non-Hodgkin’s lymphoma of the prostate are globally rare. The present study reports a case of prostatic diffuse large B-cell lymphoma (DLBCL) with intractable hematuria in a 75-year-old male. The patient presented with difficulties in urination and gross hematuria. A prostate biopsy was performed immediately, followed by conservative treatment for bleeding. A bilateral iliac arteriography and chemoembolization were then performed as emergency procedures under local anesthesia due to significant bleeding and a sharply decreased blood pressure, indicating the failure of the conservative treatment. Consequently, the bleeding was effectively controlled. Pathological examination of the prostate biopsy confirmed the presence of a DLBCL of non-germinal center B-cell origin. Immunohistochemical examination demonstrated cluster of differentiation (CD)20(++), CD3(+), leukocyte common antigen(+++), B-cell lymphoma-2(+) and prostate-specific antigen(−) results. Due to the poor general condition and low hemoglobin levels of the patient, a low-dose Rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy regimen was administered. Subsequent to three courses of chemotherapy, the patient achieved complete remission. In conclusion, combining R-CHOP and bilateral selective iliac arterial chemoembolization could be a safe and effective way to treat patients with non-Hodgkin’s lymphoma of the prostate and intractable hematuria. PMID:25663879

The Most Serious Offenses and Penalties Concerning Unsafe Foods under the Food Safety Laws in Bangladesh, India, and Australia: A Critical Analysis.

PubMed

Solaiman, S M; Ali, Abu Noman M Atahar

2015-01-01

The right to food is an internationally recognized human rignt, which inherently denotes the right to safe food simply because unsafe foods cause different diseases resulting in consumer's disability, organ failure, or even early demise. Food safety currently may not be an issue of public concern in Australia, but it has been a "silent killer" for decades in both Bangladesh and India contributing to deaths of thousands and injuries of millions of others. Unscrupulous businesses have been making money at the cost of immense human casualties with almost complete impunity in Bangladesh. The situation in Bangladesh is so intractable that the government has been making laws one after another; but food traders remain undeterred, and consequently consumers continue to die from adulterated foods. This paper examines the loopholes in the definitions of the most serious offenses under three major pieces of legislation in Bangladesh, India, and Australia. It finds that all three statutes seem flawed to some extent, though they all may mutually benefit from one another in defining and clarifying the most serious food safety offenses and penalties with a view to strengthening their effectiveness.

Hematopoietic Stem Cell Transplantation for Systemic Lupus Erythematosus

PubMed Central

Marmont du Haut Champ, Alberto M.

2012-01-01

Two streams of research are at the origin of the utilization of hematopoietic stem cell transplantation (HSCT) for severe autoimmune diseases (SADs). The allogeneic approach came from experimental studies on lupus mice, besides clinical results in coincidental diseases. The autologous procedure was encouraged by researches on experimental neurological and rheumatic disorders. At present the number of allogeneic HSCT performed for human SADs can be estimated to not over 100 patients, and the results are not greatly encouraging, considering the significant transplant-related mortality (TRM) and the occasional development of a new autoimmune disorder and/or relapses notwithstanding full donor chimerism. Autologous HSCT for refractory SLE has become a major target. Severe cases have been salvaged, TRM is low and diminishing, and prolonged clinical remissions are obtainable. Two types of immune resetting have been established, “re-education” and regulatory T cell (Tregs) normalization. Allogeneic HSCT for SLE seems best indicated for patients with disease complicated by an oncohematologic malignancy. Autologous HSCT is a powerful salvage therapy for otherwise intractable SLE. The duration of remission in uncertain, but a favorable response to previously inactive treatments is a generally constant feature. The comparison with new biological agents, or the combination of both, are to be ascertained. PMID:22969816

Weeds of Hawaii’s lands devoted to watershed protection and biodiversity conservation: Role of biological control as the missing piece in an integrated pest management strategy

USGS Publications Warehouse

Medeiros, Arthur C.; Loope, L.L.

2011-01-01

Despite Hawaii’s reputation as an extinction icon, significant biological resources remain, especially in watersheds, natural areas, and specialized edaphic sites (e.g., lava dry forest, coastal). While direct habitat destruction by humans continues, human-facilitated biological invaders are currently the primary agents of continuing degradation. The ability of invasive plants to have prolific seed production, efficient dispersal systems, and to become established in dense vegetation, complicated by Hawaii’s rugged topography, appears to render mechanical and chemical control as mere holding actions. Costly, ‘environmentally unfriendly’, and often ineffective, strategies using chemical and mechanical control on a large scale, despite the most valiant of efforts, can be viewed simply as attempts to buy time. Without increased levels of safely tested biological control, the seemingly inevitable result is the landscape level transformation of native forests, with potentially catastrophic consequences to cultural, biological, water, and economic resources. Increased levels of effective biological control for certain intractable invasive species appear to comprise a conspicuous ‘missing piece’ in our efforts to protect Hawaiian watersheds and other conservation lands.

Machines, medication, modulation: circuits of dependency and self-care in Las Vegas.

PubMed

Schüll, Natasha Dow

2006-06-01

The intensive entertainment infrastructure of Las Vegas is overlaid with a robust therapeutic network for those who become addicted to its technologies. Although the objectives of gambling machines and addiction therapeutics are seemingly at odds--the first work to encourage play, the second to stop it--both gear their interventions around a model of the self as a continuum of behavioral potentials that can be externally modulated. For compulsive gamblers implicated in this circuit of modulation, pharmaceutical drugs that have been prescribed to dampen cravings for machine play sometimes function as intensifiers of its effects. Caught in an intractable play between technologies of harm and technologies of care, recovering gambling addicts are challenged to assemble a technical array through which they can maintain balance; health itself, for these individuals, becomes a state of managed dependency. This essay explores the shifting terms and changing stakes of subjectivity and health in the contemporary United States by way of ethnographic research on compulsive gamblers who live and work in Las Vegas. The analysis draws on interviews with gamblers as well as on observations in local self-help groups, directed group therapy sessions, and chat rooms of Internet recovery Web sites.

Vertebral body innervation: Implications for pain.

PubMed

Buonocore, Michelangelo; Aloisi, Anna Maria; Barbieri, Massimo; Gatti, Anna Maria; Bonezzi, Cesare

2010-03-01

Vertebral fractures often cause intractable pain. To define the involvement of vertebral body innervation in pain, we collected specimens from male and female patients during percutaneous kyphoplasty, a procedure used for reconstruction of the vertebral body. Specimens were taken from 31 patients (9 men and 22 women) suffering high-intensity pain before surgery. In total, 1,876 histological preparations were obtained and analysed. Immunohistochemical techniques were used to locate the nerves in the specimens. The nerve fibres were labelled by indirect immunofluorescence with the primary antibody directed against Protein Gene Product 9.5 (PGP 9.5), a pan-neuronal marker; another primary antibody directed against type IV collagen (Col IV) was used to identify vessels and to determine their relationship with vertebral nerve fibres. The mean percentage of samples in which it was possible to identify nerve fibres was 35% in men and 29% in women. The percentages varied depending on the spinal level considered and the sex of the subject, nerve fibres being mostly present around vessels (95%). In conclusion, there is scarce innervation of the vertebral bodies, with a clear prevalence of fibres located around vessels. It seems unlikely that this pattern of vertebral body innervation is involved in vertebral pain or in pain relief following kyphoplasty.

Preclinical and Clinical Studies of Unrelieved Aural Fullness following Intratympanic Gentamicin Injection in Patients with Intractable Ménière’s Disease

PubMed Central

Zhai, Feng; Zhang, Ru; Zhang, Ting; Steyger, Peter S.; Dai, Chun-Fu

2014-01-01

Objective To clarify whether gentamicin affects vestibular dark cells in guinea pigs and relieves patients of aural fullness with intractable Ménière’s disease following intratympanic administration. Materials and Methods Purified gentamicin-Texas Red (GTTR) was injected intratympanically in guinea pigs that were sacrificed at 1, 3, 7, 14 and 28 days. GTTR uptake was examined in hair cells, and transitional cells and dark cells in vestibular end-organs were examined. Specific attention was paid to its distribution in dark cells under confocal microscopy, and the ultrastructure of dark cells using electron microscopy, following intratympanic injection. Results Dark cells in the semicircular canals showed weak GTTR uptake at 1, 3, 7, 14 and 28 days after intratympanic injection, with no significant differences at various time points after injection. However, the adjacent transitional cells demonstrated intense GTTR uptake that was retained for at least 28 days. Ultrastructural studies demonstrated negligible characteristics associated with apoptosis or necrosis in these dark cells. The tight junctions between dark cells showed no signs of disruption at 7 or 28 days after injection. Conclusion Intratympanic gentamicin has little direct impact on vestibular dark cells. Clinical Application A modified low-dose titration intratympanic approach was used in 29 patients with intractable vertigo and the clinical outcomes were followed. Aural fullness following intratympanic gentamicin injection was not relieved based on our subjective scales, demonstrated by no statistically significant difference between preinjection (4.16 ± 3.08) and postinjection (3.58 ± 2.93; p > 0.05) aural fullness scores. Vertigo control was achieved in 88% of patients, with hearing deterioration identified in 16% of patients. Intratympanic gentamicin administration might not lead to relief of aural fullness in patients with intractable vertigo, although it can achieve a high vertigo control rate with some cochleotoxicity. PMID:24008307

Quality of life after surgery for intractable partial epilepsy in children: a cohort study with controls.

PubMed

Mikati, Mohamad A; Ataya, Nour; Ferzli, Jessica; Kurdi, Rana; El-Banna, Diana; Rahi, Amal; Shamseddine, Alhan; Sinno, Durriyah; Comair, Youssef

2010-08-01

Investigate if quality of life (QOL) normalizes on long-term follow-up after surgery for partial epilepsy in children. This is a cohort study with controls in which a consecutive cohort of nineteen 2-14-year-old children who underwent focal resections for intractable partial seizures between 1996 and 2006, were matched with 19 non-surgery intractable partial epilepsy patients, and with 19 healthy subjects. The two epilepsy groups were matched for age, sex, socio-economic status (SES), cognitive level, seizure type, and seizure frequency. The healthy group was matched with the two epilepsy groups for age, sex, SES, and cognitive level. QOL was assessed using the QOLCE (Quality of Life in Childhood Epilepsy Questionnaire). In the surgery group (follow-up 3.84+/-2.26 years), 78.9% had Engel class-I versus 21.1% in non-surgery (p=0.01) (follow-up 3.44+/-2.95 years). Surgery patients were similar to healthy subjects in the social, emotional, cognitive, behavioral, and overall QOL (p>0.05) but had lower scores in the total QOL, physical, and health domains (p<0.05). Surgery patients scored better than non-surgery in the behavioral domain and the HASES (Hague Side Effects Scale) score (p<0.05). Non-surgery patients scored worse than healthy in total QOL, physical, behavioral, health, and overall QOL (p<0.05). IQ, HASS (Hague Seizure Severity Scale), and HASES scores were positively associated with total QOL score (p<0.05). Subgroup analysis on seizure-free surgery patients showed that they did not differ from healthy subjects in any of QOL domains (p>0.05, power>0.8). Our data indicate that epilepsy surgery for partial seizures in children is associated with better QOL as compared to children with intractable epilepsy who are not operated on, and suggest that in those who achieve seizure freedom normal QOL may at least potentially be possible.

Targeted School Violence and the Web of Causes: Risk Factors and the Problems of Specificity. Commentary on: "Bullying, Romantic Rejection, and Conflicts with Teachers: The Crucial Role of Social Dynamics in the Development of School Shootings--A Systematic Review"

ERIC Educational Resources Information Center

Böckler, Nils; Roth, Viktoria; Stetten, Lina; Zick, Andreas

2014-01-01

The authors begin their commentary by saying that looking at the phenotypical characteristics of a school shooting, which focus on the perpetrators' experiences in school contexts seems to be overdue. In spite of methodological problems, the studies involved in the review seem to paint a clear picture with regard to social ostracism and harassment…

[Medical surveillance in university: organizational difficulties, legal problems, scientific e technical specificities. Experience of University of Milan Bicocca].

PubMed

D'Orso, M I; Giuliani, C; Assini, R; Riva, M A; Cesana, G

2012-01-01

Our research describes activities of Occupational Health carried out during last year in University of Milan Bicocca by Occupational Doctors. We describe results of medical surveillance in 1153 employees or students exposed to occupational risks for health and safety. We report results obtained, technical difficulties, organizational problems, and preventive actions decided to improve functionality of our activity. Students seem to be less protected and consequently seem to have higher professional safety and health risks.

Must "Hard Problems" Be Hard?

ERIC Educational Resources Information Center

Kolata, Gina

1985-01-01

To determine how hard it is for computers to solve problems, researchers have classified groups of problems (polynomial hierarchy) according to how much time they seem to require for their solutions. A difficult and complex proof is offered which shows that a combinatorial approach (using Boolean circuits) may resolve the problem. (JN)

External approach to rhinoplasty.

PubMed

Goodman, Wilfred S; Charbonneau, Paul A

2015-07-01

The technique of external rhinoplasty is outlined. Having reviewed 74 cases, its advantages and disadvantages are discussed. Reluctance to use this external approach seems to be based on emotional rather than radical grounds, for its seems to be the procedure of choice for many problems.

What Does (and Doesn't) Make Analogical Problem Solving Easy? A Complexity-Theoretic Perspective

ERIC Educational Resources Information Center

Wareham, Todd; Evans, Patricia; van Rooij, Iris

2011-01-01

Solving new problems can be made easier if one can build on experiences with other problems one has already successfully solved. The ability to exploit earlier problem-solving experiences in solving new problems seems to require several cognitive sub-abilities. Minimally, one needs to be able to retrieve relevant knowledge of earlier solved…

High-dose intravenous levetiracetam for acute seizure exacerbation in children with intractable epilepsy.

PubMed

Depositario-Cabacar, Dewi T; Peters, Jurriaan M; Pong, Amanda W; Roth, Julie; Rotenberg, Alexander; Riviello, James J; Takeoka, Masanori

2010-07-01

We review our experience with high-dose intravenous levetiracetam (IV-LEV) for acute seizure exacerbations in nine children with medically intractable epilepsy. All children had acute repetitive seizures-while on chronic antiepileptic drugs-that either led to hospitalization (eight) or occurred during hospitalization (one), and received doses of IV-LEV of 150 mg/kg/day or greater, with a mean dose of 228 +/- 48 mg/kg/day. Eight of nine children had resolution of the acute repetitive seizures. Seizure frequency was reduced to less than baseline in seven children (seizure-free in two, >/=80% reduction in four, and 50% reduction in one). Except for one child with increased seizures, IV-LEV was well tolerated in all children without complications.

Implicit methods for efficient musculoskeletal simulation and optimal control

PubMed Central

van den Bogert, Antonie J.; Blana, Dimitra; Heinrich, Dieter

2011-01-01

The ordinary differential equations for musculoskeletal dynamics are often numerically stiff and highly nonlinear. Consequently, simulations require small time steps, and optimal control problems are slow to solve and have poor convergence. In this paper, we present an implicit formulation of musculoskeletal dynamics, which leads to new numerical methods for simulation and optimal control, with the expectation that we can mitigate some of these problems. A first order Rosenbrock method was developed for solving forward dynamic problems using the implicit formulation. It was used to perform real-time dynamic simulation of a complex shoulder arm system with extreme dynamic stiffness. Simulations had an RMS error of only 0.11 degrees in joint angles when running at real-time speed. For optimal control of musculoskeletal systems, a direct collocation method was developed for implicitly formulated models. The method was applied to predict gait with a prosthetic foot and ankle. Solutions were obtained in well under one hour of computation time and demonstrated how patients may adapt their gait to compensate for limitations of a specific prosthetic limb design. The optimal control method was also applied to a state estimation problem in sports biomechanics, where forces during skiing were estimated from noisy and incomplete kinematic data. Using a full musculoskeletal dynamics model for state estimation had the additional advantage that forward dynamic simulations, could be done with the same implicitly formulated model to simulate injuries and perturbation responses. While these methods are powerful and allow solution of previously intractable problems, there are still considerable numerical challenges, especially related to the convergence of gradient-based solvers. PMID:22102983

Quantum Simulation of Helium Hydride Cation in a Solid-State Spin Register.

PubMed

Wang, Ya; Dolde, Florian; Biamonte, Jacob; Babbush, Ryan; Bergholm, Ville; Yang, Sen; Jakobi, Ingmar; Neumann, Philipp; Aspuru-Guzik, Alán; Whitfield, James D; Wrachtrup, Jörg

2015-08-25

Ab initio computation of molecular properties is one of the most promising applications of quantum computing. While this problem is widely believed to be intractable for classical computers, efficient quantum algorithms exist which have the potential to vastly accelerate research throughput in fields ranging from material science to drug discovery. Using a solid-state quantum register realized in a nitrogen-vacancy (NV) defect in diamond, we compute the bond dissociation curve of the minimal basis helium hydride cation, HeH(+). Moreover, we report an energy uncertainty (given our model basis) of the order of 10(-14) hartree, which is 10 orders of magnitude below the desired chemical precision. As NV centers in diamond provide a robust and straightforward platform for quantum information processing, our work provides an important step toward a fully scalable solid-state implementation of a quantum chemistry simulator.

Embedding dynamical networks into distributed models

NASA Astrophysics Data System (ADS)

Innocenti, Giacomo; Paoletti, Paolo

2015-07-01

Large networks of interacting dynamical systems are well-known for the complex behaviours they are able to display, even when each node features a quite simple dynamics. Despite examples of such networks being widespread both in nature and in technological applications, the interplay between the local and the macroscopic behaviour, through the interconnection topology, is still not completely understood. Moreover, traditional analytical methods for dynamical response analysis fail because of the intrinsically large dimension of the phase space of the network which makes the general problem intractable. Therefore, in this paper we develop an approach aiming to condense all the information in a compact description based on partial differential equations. By focusing on propagative phenomena, rigorous conditions under which the original network dynamical properties can be successfully analysed within the proposed framework are derived as well. A network of Fitzhugh-Nagumo systems is finally used to illustrate the effectiveness of the proposed method.

Sugar, ethics and legislation.

PubMed

Azize, Joseph

2010-05-01

There are serious ethical and legal issues concerning the sale of sugar products, especially to children, yet one cannot address children's consumption without addressing consumption across society. The ethical principles are not even controversial. However, sugar has been insufficiently scrutinised, probably because sweetness is popular and plays a prominent, but dispensable, cultural role. Sugar is both addictive and toxic, although it is a very mild, very slow-working poison. Yet, over time, its effects can be quite serious. The social and health problems have proved grave and intractable. Given the nature of sugar, it should be regulated like alcohol and tobacco, if not more stringently, given its greater social and cultural penetration across all ages. That is, sales of sugar products at school canteens should be banned, advertising severely limited, full disclosure of sugar content made mandatory, warnings placed on certain products, and sugar itself should be taxed.

Computationally efficient confidence intervals for cross-validated area under the ROC curve estimates.

PubMed

LeDell, Erin; Petersen, Maya; van der Laan, Mark

In binary classification problems, the area under the ROC curve (AUC) is commonly used to evaluate the performance of a prediction model. Often, it is combined with cross-validation in order to assess how the results will generalize to an independent data set. In order to evaluate the quality of an estimate for cross-validated AUC, we obtain an estimate of its variance. For massive data sets, the process of generating a single performance estimate can be computationally expensive. Additionally, when using a complex prediction method, the process of cross-validating a predictive model on even a relatively small data set can still require a large amount of computation time. Thus, in many practical settings, the bootstrap is a computationally intractable approach to variance estimation. As an alternative to the bootstrap, we demonstrate a computationally efficient influence curve based approach to obtaining a variance estimate for cross-validated AUC.

Successful treatment of pediatric psoriasis with Indigo naturalis composite ointment.

PubMed

Lin, Yin-Ku; Yen, Hung-Rong; Wong, Wen-Rou; Yang, Sien-Hung; Pang, Jong-Hwei Su

2006-01-01

The treatment of psoriasis in children is still an intractable problem and demands a long-term therapy with prolonged efficacy that is free from serious adverse events. Many modes of therapy are currently in use but the disease is often resistant to treatment owing to the unacceptable toxicity that leads to poor compliance. Therefore, to develop an alternative treatment is indispensable. Traditional Chinese medicine has been documented for over 1000 years to provide various effective treatments for inflammatory skin diseases. Herein, we report an 8-year-old boy with recalcitrant pediatric psoriasis who, after multiple treatment failures with conventional antipsoriatic medications, showed remarkable clinical improvement with 8 weeks of topical treatment with Indigo naturalis composite ointment. Remission has lasted for over 2 years until now. Our patient's response suggests that topical Indigo naturalis composite ointment may provide a safe and effective alternative treatment for pediatric psoriasis.

Mapping Gnss Restricted Environments with a Drone Tandem and Indirect Position Control

NASA Astrophysics Data System (ADS)

Cledat, E.; Cucci, D. A.

2017-08-01

The problem of autonomously mapping highly cluttered environments, such as urban and natural canyons, is intractable with the current UAV technology. The reason lies in the absence or unreliability of GNSS signals due to partial sky occlusion or multi-path effects. High quality carrier-phase observations are also required in efficient mapping paradigms, such as Assisted Aerial Triangulation, to achieve high ground accuracy without the need of dense networks of ground control points. In this work we consider a drone tandem in which the first drone flies outside the canyon, where GNSS constellation is ideal, visually tracks the second drone and provides an indirect position control for it. This enables both autonomous guidance and accurate mapping of GNSS restricted environments without the need of ground control points. We address the technical feasibility of this concept considering preliminary real-world experiments in comparable conditions and we perform a mapping accuracy prediction based on a simulation scenario.

An Investigation of the Cryogenic Freezing of Water in Non-Metallic Pipelines

NASA Astrophysics Data System (ADS)

Martin, C. I.; Richardson, R. N.; Bowen, R. J.

2004-06-01

Pipe freezing is increasingly used in a range of industries to solve otherwise intractable pipe line maintenance and servicing problems. This paper presents the interim results from an experimental study on deliberate freezing of polymeric pipelines. Previous and contemporary works are reviewed. The object of the current research is to confirm the feasibility of ice plug formation within a polymeric pipe as a method of isolation. Tests have been conducted on a range of polymeric pipes of various sizes. The results reported here all relate to freezing of horizontal pipelines. In each case the process of plug formation was photographed, the frozen plug pressure tested and the pipe inspected for signs of damage resulting from the freeze procedure. The time to freeze was recorded and various temperatures logged. These tests have demonstrated that despite the poor thermal and mechanical properties of the polymers, freezing offers a viable alternative method of isolation in polymeric pipelines.

Scheduling Real-Time Mixed-Criticality Jobs

NASA Astrophysics Data System (ADS)

Baruah, Sanjoy K.; Bonifaci, Vincenzo; D'Angelo, Gianlorenzo; Li, Haohan; Marchetti-Spaccamela, Alberto; Megow, Nicole; Stougie, Leen

Many safety-critical embedded systems are subject to certification requirements; some systems may be required to meet multiple sets of certification requirements, from different certification authorities. Certification requirements in such "mixed-criticality" systems give rise to interesting scheduling problems, that cannot be satisfactorily addressed using techniques from conventional scheduling theory. In this paper, we study a formal model for representing such mixed-criticality workloads. We demonstrate first the intractability of determining whether a system specified in this model can be scheduled to meet all its certification requirements, even for systems subject to two sets of certification requirements. Then we quantify, via the metric of processor speedup factor, the effectiveness of two techniques, reservation-based scheduling and priority-based scheduling, that are widely used in scheduling such mixed-criticality systems, showing that the latter of the two is superior to the former. We also show that the speedup factors are tight for these two techniques.

Graph Representations of Flow and Transport in Fracture Networks using Machine Learning

NASA Astrophysics Data System (ADS)

Srinivasan, G.; Viswanathan, H. S.; Karra, S.; O'Malley, D.; Godinez, H. C.; Hagberg, A.; Osthus, D.; Mohd-Yusof, J.

2017-12-01

Flow and transport of fluids through fractured systems is governed by the properties and interactions at the micro-scale. Retaining information about the micro-structure such as fracture length, orientation, aperture and connectivity in mesh-based computational models results in solving for millions to billions of degrees of freedom and quickly renders the problem computationally intractable. Our approach depicts fracture networks graphically, by mapping fractures to nodes and intersections to edges, thereby greatly reducing computational burden. Additionally, we use machine learning techniques to build simulators on the graph representation, trained on data from the mesh-based high fidelity simulations to speed up computation by orders of magnitude. We demonstrate our methodology on ensembles of discrete fracture networks, dividing up the data into training and validation sets. Our machine learned graph-based solvers result in over 3 orders of magnitude speedup without any significant sacrifice in accuracy.

Feasibility and benefits of laminar flow control on supersonic cruise airplanes

NASA Technical Reports Server (NTRS)

Powell, A. G.; Agrawal, S.; Lacey, T. R.

1989-01-01

An evaluation was made of the applicability and benefits of laminar flow control (LFC) technology to supersonic cruise airplanes. Ancillary objectives were to identify the technical issues critical to supersonic LFC application, and to determine how those issues can be addressed through flight and wind-tunnel testing. Vehicle types studied include a Mach 2.2 supersonic transport configuration, a Mach 4.0 transport, and two Mach 2-class fighter concepts. Laminar flow control methodologies developed for subsonic and transonic wing laminarization were extended and applied. No intractible aerodynamic problems were found in applying LFC to airplanes of the Mach 2 class, even ones of large size. Improvements of 12 to 17 percent in lift-drag ratios were found. Several key technical issues, such as contamination avoidance and excresence criteria were identified. Recommendations are made for their resolution. A need for an inverse supersonic wing design methodology is indicated.

Constructing networks with correlation maximization methods.

PubMed

Mellor, Joseph C; Wu, Jie; Delisi, Charles

2004-01-01

Problems of inference in systems biology are ideally reduced to formulations which can efficiently represent the features of interest. In the case of predicting gene regulation and pathway networks, an important feature which describes connected genes and proteins is the relationship between active and inactive forms, i.e. between the "on" and "off" states of the components. While not optimal at the limits of resolution, these logical relationships between discrete states can often yield good approximations of the behavior in larger complex systems, where exact representation of measurement relationships may be intractable. We explore techniques for extracting binary state variables from measurement of gene expression, and go on to describe robust measures for statistical significance and information that can be applied to many such types of data. We show how statistical strength and information are equivalent criteria in limiting cases, and demonstrate the application of these measures to simple systems of gene regulation.

Designing the optimal shutter sequences for the flutter shutter imaging method

NASA Astrophysics Data System (ADS)

Jelinek, Jan

2010-04-01

Acquiring iris or face images of moving subjects at larger distances using a flash to prevent the motion blur quickly runs into eye safety concerns as the acquisition distance is increased. For that reason the flutter shutter method recently proposed by Raskar et al.has generated considerable interest in the biometrics community. The paper concerns the design of shutter sequences that produce the best images. The number of possible sequences grows exponentially in both the subject' s motion velocity and desired exposure value, with their majority being useless. Because the exact solution leads to an intractable mixed integer programming problem, we propose an approximate solution based on pre - screening the sequences according to the distribution of roots in their Fourier transform. A very fast algorithm utilizing the Jury' s criterion allows the testing to be done without explicitly computing the roots, making the approach practical for moderately long sequences.

Efficient quantum walk on a quantum processor

PubMed Central

Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L.; Wang, Jingbo B.; Matthews, Jonathan C. F.

2016-01-01

The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor. PMID:27146471

A Simple Theory of Capillary-Gravity Wave Turbulence

NASA Technical Reports Server (NTRS)

Glazman, Roman E.

1995-01-01

Employing a recently proposed 'multi-wave interaction' theory, inertial spectra of capillary gravity waves are derived. This case is characterized by a rather high degree of nonlinearity and a complicated dispersion law. The absence of scale invariance makes this and some other problems of wave turbulence (e.g., nonlinear inertia gravity waves) intractable by small-perturbation techniques, even in the weak-turbulence limit. The analytical solution obtained in the present work for an arbitrary degree of nonlinearity is shown to be in reasonable agreement with experimental data. The theory explains the dependence of the wave spectrum on wind input and describes the accelerated roll-off of the spectral density function in the narrow sub-range separating scale-invariant regimes of purely gravity and capillary waves, while the appropriate (long- and short-wave) limits yield power laws corresponding to the Zakharov-Filonenko and Phillips spectra.

Computationally efficient confidence intervals for cross-validated area under the ROC curve estimates

PubMed Central

Petersen, Maya; van der Laan, Mark

2015-01-01

In binary classification problems, the area under the ROC curve (AUC) is commonly used to evaluate the performance of a prediction model. Often, it is combined with cross-validation in order to assess how the results will generalize to an independent data set. In order to evaluate the quality of an estimate for cross-validated AUC, we obtain an estimate of its variance. For massive data sets, the process of generating a single performance estimate can be computationally expensive. Additionally, when using a complex prediction method, the process of cross-validating a predictive model on even a relatively small data set can still require a large amount of computation time. Thus, in many practical settings, the bootstrap is a computationally intractable approach to variance estimation. As an alternative to the bootstrap, we demonstrate a computationally efficient influence curve based approach to obtaining a variance estimate for cross-validated AUC. PMID:26279737

An efficient method for hybrid density functional calculation with spin-orbit coupling

NASA Astrophysics Data System (ADS)

Wang, Maoyuan; Liu, Gui-Bin; Guo, Hong; Yao, Yugui

2018-03-01

In first-principles calculations, hybrid functional is often used to improve accuracy from local exchange correlation functionals. A drawback is that evaluating the hybrid functional needs significantly more computing effort. When spin-orbit coupling (SOC) is taken into account, the non-collinear spin structure increases computing effort by at least eight times. As a result, hybrid functional calculations with SOC are intractable in most cases. In this paper, we present an approximate solution to this problem by developing an efficient method based on a mixed linear combination of atomic orbital (LCAO) scheme. We demonstrate the power of this method using several examples and we show that the results compare very well with those of direct hybrid functional calculations with SOC, yet the method only requires a computing effort similar to that without SOC. The presented technique provides a good balance between computing efficiency and accuracy, and it can be extended to magnetic materials.

Treatment of tracheomalacia with Palmaz stent: a case report.

PubMed

Inan, Mustafa; Ayvaz, Süleyman; Basaran, Umit Nusret

2005-01-01

Tracheomalacia is a potentially life-threatening clinical problem. The expandable Palmaz stent can be used for the treatment of tracheomalacia. We describe a female infant with tracheomalacia who showed respiratory distress the day after birth. Tracheomalacia was diagnosed by bronchoscopic examination, computed tomography and bronchography. At 75 days of age, an expandable metallic stent (Palmaz stent) was inserted into the trachea under fluoroscopic control. The patient's respiratory status improved rapidly. Bronchoscopic examination 6 months after the insertion did not show any granulation tissue. However, in bronchoscopic examination carried out two years later, we detected invasion of the Palmaz stent to the trachea and development of granulation tissue. We think that expandable metallic stent placement should be considered in patients who show intractable respiratory symptoms caused by tracheomalacia in the earlier stages of the treatment. But long-term complications of this procedure are crucial.

Retrieving the aerosol complex refractive index using PyMieScatt: A Mie computational package with visualization capabilities

NASA Astrophysics Data System (ADS)

Sumlin, Benjamin J.; Heinson, William R.; Chakrabarty, Rajan K.

2018-01-01

The complex refractive index m = n + ik of a particle is an intrinsic property which cannot be directly measured; it must be inferred from its extrinsic properties such as the scattering and absorption cross-sections. Bohren and Huffman called this approach "describing the dragon from its tracks", since the inversion of Lorenz-Mie theory equations is intractable without the use of computers. This article describes PyMieScatt, an open-source module for Python that contains functionality for solving the inverse problem for complex m using extensive optical and physical properties as input, and calculating regions where valid solutions may exist within the error bounds of laboratory measurements. Additionally, the module has comprehensive capabilities for studying homogeneous and coated single spheres, as well as ensembles of homogeneous spheres with user-defined size distributions, making it a complete tool for studying the optical behavior of spherical particles.

A review of the biology and control of the coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae).

PubMed

Damon, A

2000-12-01

The coffee berry borer, Hypothenemus hampei Ferrari, is a serious problem for the majority of the world's coffee growers and has proved to be one of the most intractable of present day pests. Despite a great deal of research, control still depends largely on the application of the organochlorine insecticide endosulfan, which is damaging to the environment, or a series of cultural and biological control methods which give variable and unpredictable results. This review summarizes the most important aspects of the biology and ecology of H. hampei and its control and identifies weak points in the knowledge about this pest. Emphasis is placed upon an analysis of the non-chemical control methods available and suggestions are offered for novel ecological and environmental factors worthy of further research, in the search for viable and sustainable control methods.

Spinal cord compression in a patient with a pain pump for failed back syndrome: a chalk-like precipitate mimicking a spinal cord neoplasm: case report.

PubMed

Wadhwa, Rishi K; Shaya, Mark R; Nanda, Anil

2006-02-01

The use of intrathecal morphine has been effective with few complications for chronic intractable pain of both benign and malignant origins. A rare but serious problem that exists is the formation of an inflammatory mass at the catheter tip of the pain pump. We report the case of a 67-year-old female patient with failed back syndrome who presented with sensory complaints and back pain. Magnetic resonance imaging revealed impingement on the thoracic cord by a mass. The mass was originally thought to be a spinal cord tumor; however, operation and chemical analysis of the mass showed that it was a bupivacaine precipitate at the tip of the catheter of the pain pump. This is the first such case, to our knowledge, of a bupivacaine precipitate mimicking a spinal cord tumor.

A finite-element model for moving contact line problems in immiscible two-phase flow

NASA Astrophysics Data System (ADS)

Kucala, Alec

2017-11-01

Accurate modeling of moving contact line (MCL) problems is imperative in predicting capillary pressure vs. saturation curves, permeability, and preferential flow paths for a variety of applications, including geological carbon storage (GCS) and enhanced oil recovery (EOR). The macroscale movement of the contact line is dependent on the molecular interactions occurring at the three-phase interface, however most MCL problems require resolution at the meso- and macro-scale. A phenomenological model must be developed to account for the microscale interactions, as resolving both the macro- and micro-scale would render most problems computationally intractable. Here, a model for the moving contact line is presented as a weak forcing term in the Navier-Stokes equation and applied directly at the location of the three-phase interface point. The moving interface is tracked with the level set method and discretized using the conformal decomposition finite element method (CDFEM), allowing for the surface tension and the wetting model to be computed at the exact interface location. A variety of verification test cases for simple two- and three-dimensional geometries are presented to validate the current MCL model, which can exhibit grid independence when a proper scaling for the slip length is chosen. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525.

Uncertainty vs. Information (Invited)

NASA Astrophysics Data System (ADS)

Nearing, Grey

2017-04-01

Information theory is the branch of logic that describes how rational epistemic states evolve in the presence of empirical data (Knuth, 2005), and any logic of science is incomplete without such a theory. Developing a formal philosophy of science that recognizes this fact results in essentially trivial solutions to several longstanding problems are generally considered intractable, including: • Alleviating the need for any likelihood function or error model. • Derivation of purely logical falsification criteria for hypothesis testing. • Specification of a general quantitative method for process-level model diagnostics. More generally, I make the following arguments: 1. Model evaluation should not proceed by quantifying and/or reducing error or uncertainty, and instead should be approached as a problem of ensuring that our models contain as much information as our experimental data. I propose that the latter is the only question a scientist actually has the ability to ask. 2. Instead of building geophysical models as solutions to differential equations that represent conservation laws, we should build models as maximum entropy distributions constrained by conservation symmetries. This will allow us to derive predictive probabilities directly from first principles. Knuth, K. H. (2005) 'Lattice duality: The origin of probability and entropy', Neurocomputing, 67, pp. 245-274.

Prediction and causal reasoning in planning

NASA Technical Reports Server (NTRS)

Dean, T.; Boddy, M.

1987-01-01

Nonlinear planners are often touted as having an efficiency advantage over linear planners. The reason usually given is that nonlinear planners, unlike their linear counterparts, are not forced to make arbitrary commitments to the order in which actions are to be performed. This ability to delay commitment enables nonlinear planners to solve certain problems with far less effort than would be required of linear planners. Here, it is argued that this advantage is bought with a significant reduction in the ability of a nonlinear planner to accurately predict the consequences of actions. Unfortunately, the general problem of predicting the consequences of a partially ordered set of actions is intractable. In gaining the predictive power of linear planners, nonlinear planners sacrifice their efficiency advantage. There are, however, other advantages to nonlinear planning (e.g., the ability to reason about partial orders and incomplete information) that make it well worth the effort needed to extend nonlinear methods. A framework is supplied for causal inference that supports reasoning about partially ordered events and actions whose effects depend upon the context in which they are executed. As an alternative to a complete but potentially exponential-time algorithm, researchers provide a provably sound polynomial-time algorithm for predicting the consequences of partially ordered events.

A Lifetime Maximization Relay Selection Scheme in Wireless Body Area Networks.

PubMed

Zhang, Yu; Zhang, Bing; Zhang, Shi

2017-06-02

Network Lifetime is one of the most important metrics in Wireless Body Area Networks (WBANs). In this paper, a relay selection scheme is proposed under the topology constrains specified in the IEEE 802.15.6 standard to maximize the lifetime of WBANs through formulating and solving an optimization problem where relay selection of each node acts as optimization variable. Considering the diversity of the sensor nodes in WBANs, the optimization problem takes not only energy consumption rate but also energy difference among sensor nodes into account to improve the network lifetime performance. Since it is Non-deterministic Polynomial-hard (NP-hard) and intractable, a heuristic solution is then designed to rapidly address the optimization. The simulation results indicate that the proposed relay selection scheme has better performance in network lifetime compared with existing algorithms and that the heuristic solution has low time complexity with only a negligible performance degradation gap from optimal value. Furthermore, we also conduct simulations based on a general WBAN model to comprehensively illustrate the advantages of the proposed algorithm. At the end of the evaluation, we validate the feasibility of our proposed scheme via an implementation discussion.

Data-driven backward chaining

NASA Technical Reports Server (NTRS)

Haley, Paul

1991-01-01

The C Language Integrated Production System (CLIPS) cannot effectively perform sound and complete logical inference in most real-world contexts. The problem facing CLIPS is its lack of goal generation. Without automatic goal generation and maintenance, forward chaining can only deduce all instances of a relationship. Backward chaining, which requires goal generation, allows deduction of only that subset of what is logically true which is also relevant to ongoing problem solving. Goal generation can be mimicked in simple cases using forward chaining. However, such mimicry requires manual coding of additional rules which can assert an inadequate goal representation for every condition in every rule that can have corresponding facts derived by backward chaining. In general, for N rules with an average of M conditions per rule the number of goal generation rules required is on the order of N*M. This is clearly intractable from a program maintenance perspective. We describe the support in Eclipse for backward chaining which it automatically asserts as it checks rule conditions. Important characteristics of this extension are that it does not assert goals which cannot match any rule conditions, that 2 equivalent goals are never asserted, and that goals persist as long as, but no longer than, they remain relevant.

Cooperative inference: Features, objects, and collections.

PubMed

Searcy, Sophia Ray; Shafto, Patrick

2016-10-01

Cooperation plays a central role in theories of development, learning, cultural evolution, and education. We argue that existing models of learning from cooperative informants have fundamental limitations that prevent them from explaining how cooperation benefits learning. First, existing models are shown to be computationally intractable, suggesting that they cannot apply to realistic learning problems. Second, existing models assume a priori agreement about which concepts are favored in learning, which leads to a conundrum: Learning fails without precise agreement on bias yet there is no single rational choice. We introduce cooperative inference, a novel framework for cooperation in concept learning, which resolves these limitations. Cooperative inference generalizes the notion of cooperation used in previous models from omission of labeled objects to the omission values of features, labels for objects, and labels for collections of objects. The result is an approach that is computationally tractable, does not require a priori agreement about biases, applies to both Boolean and first-order concepts, and begins to approximate the richness of real-world concept learning problems. We conclude by discussing relations to and implications for existing theories of cognition, cognitive development, and cultural evolution. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Typhoid fever as a triggering factor in acute and intractable bronchial asthma attack.

PubMed

Wardhana; Surachmanto, Eko E; Datau, E A

2013-10-01

Typhoid fever is an enteric infection caused by Salmonella typhi. In Indonesia, typhoid fever is endemic with high incidence of the disease. In daily practice we frequently have patients with bronchial asthma, and it is becoming worse when these patients get typhoid fever. After oral ingestion, Salmonella typhi invades the the intestine mucosa after conducted by microbial binding to epithelial cells, destroying the microfold cells (M cell) then passed through the lamina propria and detected by dendritic cells (DC) which express a variety of pathogen recognition receptors on the surfaces, including Toll-Like Receptor (TLR). expressed on macrophages and on intestinal epithelial cells inducing degradation of IB, and translocation of NF-B (Nuclear Factor-Kappa Beta). This process initiates the induction of pro-inflammatory gene expression profile adhesion molecules, chemokines, adhesion molecules, and other proteins that induce and perpetuate the inflammation in host cells then will induce acute ant intractable attack of bronchial asthma. The role of typhoid fever in bronchial asthma, especially in persons with acute attack of bronchial asthma, is not well understood. In this article, we will discuss the role of typhoid fever in the bronchial asthma patients which may cause bronchial asthma significantly become more severe even triggering the acute and intractable attack of bronchial asthma. This fact makes an important point, to treat completely the typhoid fever in patients with bronchial asthma.

Ahmed glaucoma valve in eyes with preexisting episcleral encircling element

PubMed Central

Choudhari, Nikhil Shreeram; George, Ronnie; Shantha, Balekudaru; Neog, Aditya; Tripathi, Shweta; Srinivasan, Bhaskar; Vijaya, Lingam

2014-01-01

Background: To describe the use of Ahmed glaucoma valve (AGV) in the management of intractable glaucoma in eyes with a preexisting episcleral encircling element. Materials and Methods: This is a retrospective, consecutive, noncomparative study. The study included 12 eyes of 12 patients with a preexisting episcleral encircling element that underwent implantation of silicone AGV to treat intractable glaucoma during January 2009 to September 2010. Results: The mean patient age was 25.6 (standard deviation 17.1) years. Five (41.6%) patients were monocular. The indications for AGV were varied. The mean duration between placement of episcleral encircling element and implantation of AGV was 30.5 (33.8) months. The mean follow-up was 37.4 (22.9) weeks. Preoperatively, the mean intraocular pressure (IOP) was 31.4 (7.9) mmHg and the mean antiglaucoma medications were 2.8. At the final postoperative follow-up, the mean IOP was 12.5 (3.5) mmHg and the mean number of antiglaucoma medications was 0.8 (P < 0.001). The complications observed over the follow-up period did include corneal graft failure in three eyes, tube erosion in two eyes and rhegmatogenous retinal detachment in one eye. Conclusion: AGV is an effective option in the management of intractable glaucoma in eyes with a preexisting episcleral encircling element keeping in mind the possibility of significant postoperative complications. PMID:24881603

ST-Segment Elevation Myocardial Infarction with Acute Stent Thrombosis Presenting as Intractable Hiccups: An Unusual Case

PubMed Central

Zhang, Fan; Tongo, Nosakhare Douglas; Hastings, Victoria; Kanzali, Parisa; Zhu, Ziqiang; Chadow, Hal; Rafii, Shahrokh E.

2017-01-01

Patient: Male, 51 Final Diagnosis: ST-segment elevation myocardial infarction with acute stent thrombosis Symptoms: Chest pain • hiccups Medication: — Clinical Procedure: — Specialty: Cardiology Objective: Unusual clinical course Background: Acute coronary syndrome (ACS) can present with atypical chest pain or symptoms not attributed to heart disease, such as indigestion. Hiccups, a benign and self-limited condition, can become persistent or intractable with overlooked underlying etiology. There are various causes of protracted hiccups, including metabolic abnormalities, psychogenic disorders, malignancy, central nervous system pathology, medications, pulmonary disorders, or gastrointestinal etiologies. It is rarely attributed to cardiac disease. Case Report: We report a case of intractable hiccups in a 51-year-old male with cocaine related myocardial infarction (MI) before and after stent placement. Coronary angiogram showed in-stent thrombosis of the initial intervention. Following thrombectomy, balloon angioplasty, and stent, the patient recovered well without additional episodes of hiccups. Although hiccups are not known to present with a predilection for a particular cause of myocardial ischemia, this case may additionally be explained by the sympathomimetic effects of cocaine, which lead to vasoconstriction of coronary arteries. Conclusions: Hiccups associated with cardiac enzyme elevation and EKG ST-segment elevation before and after percutaneous coronary intervention (PCI) maybe a manifestation of acute MI with or without stent. The fact that this patient was a cocaine user may have contributed to the unique presentation. PMID:28455489

Atypical language laterality is associated with large-scale disruption of network integration in children with intractable focal epilepsy.

PubMed

Ibrahim, George M; Morgan, Benjamin R; Doesburg, Sam M; Taylor, Margot J; Pang, Elizabeth W; Donner, Elizabeth; Go, Cristina Y; Rutka, James T; Snead, O Carter

2015-04-01

Epilepsy is associated with disruption of integration in distributed networks, together with altered localization for functions such as expressive language. The relation between atypical network connectivity and altered localization is unknown. In the current study we tested whether atypical expressive language laterality was associated with the alteration of large-scale network integration in children with medically-intractable localization-related epilepsy (LRE). Twenty-three right-handed children (age range 8-17) with medically-intractable LRE performed a verb generation task in fMRI. Language network activation was identified and the Laterality index (LI) was calculated within the pars triangularis and pars opercularis. Resting-state data from the same cohort were subjected to independent component analysis. Dual regression was used to identify associations between resting-state integration and LI values. Higher positive values of the LI, indicating typical language localization were associated with stronger functional integration of various networks including the default mode network (DMN). The normally symmetric resting-state networks showed a pattern of lateralized connectivity mirroring that of language function. The association between atypical language localization and network integration implies a widespread disruption of neural network development. These findings may inform the interpretation of localization studies by providing novel insights into reorganization of neural networks in epilepsy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Noninvasive testing, early surgery, and seizure freedom in tuberous sclerosis complex.

PubMed

Wu, J Y; Salamon, N; Kirsch, H E; Mantle, M M; Nagarajan, S S; Kurelowech, L; Aung, M H; Sankar, R; Shields, W D; Mathern, G W

2010-02-02

The unambiguous identification of the epileptogenic tubers in individuals with tuberous sclerosis complex (TSC) can be challenging. We assessed whether magnetic source imaging (MSI) and coregistration of (18)fluorodeoxyglucose PET (FDG-PET) with MRI could improve the identification of the epileptogenic regions noninvasively in children with TSC. In addition to standard presurgical evaluation, 28 children with intractable epilepsy from TSC referred from 2000 to 2007 had MSI and FDG-PET/MRI coregistration without extraoperative intracranial EEG. Based on the concordance of test results, 18 patients with TSC (64%) underwent surgical resection, with the final resection zone confirmed by intraoperative electrocorticography. Twelve patients are seizure free postoperatively (67%), with an average follow-up of 4.1 years. Younger age at surgery and shorter seizure duration were associated with postoperative seizure freedom. Conversely, older age and longer seizure duration were linked with continued seizures postoperatively or prevented surgery because of nonlateralizing or bilateral independent epileptogenic zones. Complete removal of presurgery MSI dipole clusters correlated with postoperative seizure freedom. Magnetic source imaging and (18)fluorodeoxyglucose PET/MRI coregistration noninvasively localized the epileptogenic zones in many children with intractable epilepsy from tuberous sclerosis complex (TSC), with 67% seizure free postoperatively. Seizure freedom after surgery correlated with younger age and shorter seizure duration. These findings support the concept that early epilepsy surgery is associated with seizure freedom in children with TSC and intractable epilepsy.

Cognitive Abilities Adjustment and Parenting Practices in Preschoolers with Disruption Conduct Problems

ERIC Educational Resources Information Center

Fernandez-Parra, A.; Lopez-Rubio, S.; Mata, S.; Calero, M. D.; Vives, M. C.; Carles, R.; Navarro, E.

2013-01-01

Introduction: Conduct problems arising in infancy are one of the main reasons for which parents seek psychological assistance. Although these problems usually begin when the child has started school, in recent years a group of children has been identified who begin to manifest such problems from their earliest infancy and whose prognosis seems to…