Science.gov

Sample records for advance theoretical understanding

  1. Advances in the theoretical understanding of photon upconversion in rare-earth activated nanophosphors.

    PubMed

    Liu, Guokui

    2015-03-21

    Photon upconversion in rare earth activated phosphors involves multiple mechanisms of electronic transitions. Stepwise optical excitation, energy transfer, and various nonlinear and collective light-matter interaction processes act together to convert low-energy photons into short-wavelength light emission. Upconversion luminescence from nanomaterials exhibits additional size and surface dependencies. A fundamental understanding of the overall performance of an upconversion system requires basic theories on the spectroscopic properties of solids containing rare earth ions. This review article surveys the recent progress in the theoretical interpretations of the spectroscopic characteristics and luminescence dynamics of photon upconversion in rare earth activated phosphors. The primary aspects of upconversion processes, including energy level splitting, transition probability, line broadening, non-radiative relaxation and energy transfer, are covered with an emphasis on interpreting experimental observations. Theoretical models and methods for analyzing nano-phenomena in upconversion are introduced with detailed discussions on recently reported experimental results.

  2. Advances in understanding of chemical bonding: inputs from experimental and theoretical charge density analysis.

    PubMed

    Chopra, Deepak

    2012-10-11

    The development of charge density analysis has undergone a major renaissance in the last two decades. In recent years, the characterization of bonding features associated with atoms in molecules and in crystals has been explored using high-resolution X-ray diffraction data (laboratory or synchrotron) complemented by high level ab initio theoretical calculations. The extraction of one electron topological properties, namely, electrostatic charges, dipole moment and higher moments, electrostatic potential, electric field gradients, in addition to evaluation of the local kinetic and potential energy densities, have contributed toward an understanding of the electron density distributions in molecular solids. New topological descriptors, namely, the source function (SF) and electron localization function (ELF) provide additional information as regards characterization of the topology of the electron density. In addition, delocalization indices have also been developed to account for bonding features pertinent to M-M bonds. The evaluation of these properties have contributed significantly toward the understanding of intra- and intermolecular bonding features in organic, inorganic, and biomolecules in the crystalline phase, with concomitant applications in the understanding of chemical reactivity and material/biological properties. In recent years, the focus has strongly shifted toward the understanding of structure-property relationships in organometallic complexes containing labile M-C bonds in the crystal structure with subsequent implications in catalysis. This perspective aims to highlight the major developments in electron density measurements in the past few years and provides pointers directed toward the potential use of this technique in future applications for an improved understanding of chemical bonding in systems that have been unexplored.

  3. The Ease of Language Understanding (ELU) model: theoretical, empirical, and clinical advances

    PubMed Central

    Rönnberg, Jerker; Lunner, Thomas; Zekveld, Adriana; Sörqvist, Patrik; Danielsson, Henrik; Lyxell, Björn; Dahlström, Örjan; Signoret, Carine; Stenfelt, Stefan; Pichora-Fuller, M. Kathleen; Rudner, Mary

    2013-01-01

    Working memory is important for online language processing during conversation. We use it to maintain relevant information, to inhibit or ignore irrelevant information, and to attend to conversation selectively. Working memory helps us to keep track of and actively participate in conversation, including taking turns and following the gist. This paper examines the Ease of Language Understanding model (i.e., the ELU model, Rönnberg, 2003; Rönnberg et al., 2008) in light of new behavioral and neural findings concerning the role of working memory capacity (WMC) in uni-modal and bimodal language processing. The new ELU model is a meaning prediction system that depends on phonological and semantic interactions in rapid implicit and slower explicit processing mechanisms that both depend on WMC albeit in different ways. It is based on findings that address the relationship between WMC and (a) early attention processes in listening to speech, (b) signal processing in hearing aids and its effects on short-term memory, (c) inhibition of speech maskers and its effect on episodic long-term memory, (d) the effects of hearing impairment on episodic and semantic long-term memory, and finally, (e) listening effort. New predictions and clinical implications are outlined. Comparisons with other WMC and speech perception models are made. PMID:23874273

  4. Silicene: Recent theoretical advances

    NASA Astrophysics Data System (ADS)

    Lew Yan Voon, L. C.; Zhu, Jiajie; Schwingenschlögl, Udo

    2016-12-01

    Silicene is a two-dimensional allotrope of silicon with a puckered hexagonal structure closely related to the structure of graphene and that has been predicted to be stable. To date, it has been successfully grown in solution (functionalized) and on substrates. The goal of this review is to provide a summary of recent theoretical advances in the properties of both free-standing silicene as well as in interaction with molecules and substrates, and of proposed device applications.

  5. A Review of Theoretical and Empirical Advancements

    ERIC Educational Resources Information Center

    Wang, Mo; Henkens, Kene; van Solinge, Hanna

    2011-01-01

    In this article, we review both theoretical and empirical advancements in retirement adjustment research. After reviewing and integrating current theories about retirement adjustment, we propose a resource-based dynamic perspective to apply to the understanding of retirement adjustment. We then review empirical findings that are associated with…

  6. Theoretical Advanced Study Institute: 2014

    SciTech Connect

    DeGrand, Thomas

    2016-08-17

    The Theoretical Advanced Study Institute (TASI) was held at the University of Colorado, Boulder, during June 2-27, 2014. The topic was "Journeys through the Precision Frontier: Amplitudes for Colliders." The organizers were Professors Lance Dixon (SLAC) and Frank Petriello (Northwestern and Argonne). There were fifty-one students. Nineteen lecturers gave sixty seventy-five minute lectures. A Proceedings was published. This TASI was unique for its large emphasis on methods for calculating amplitudes. This was embedded in a program describing recent theoretical and phenomenological developments in particle physics. Topics included introductions to the Standard Model, to QCD (both in a collider context and on the lattice), effective field theories, Higgs physics, neutrino interactions, an introduction to experimental techniques, and cosmology.

  7. Theoretical understanding of chromospheric inhomogeneities

    NASA Technical Reports Server (NTRS)

    Delache, P.

    1973-01-01

    Detailed theoretical studies of chromospheric inhomogeneities consider dynamics as well as radiative transfer of mass flow as a consequence of energy deposition. It is shown that pressure is exerted by the heating waves, especially in inhomogeneous structures, where they can be defracted. A dynamical model is formulated that depicts the inhomogeneous structure of the chromosphere-corona transition region through mass flow regimes.

  8. Theoretical understanding of charm decays

    SciTech Connect

    Bigi, I.I.

    1986-08-01

    A detailed description of charm decays has emerged. The various concepts involved are sketched. Although this description is quite successful in reproducing the data the chapter on heavy flavour decays is far from closed. Relevant questions like on th real strength of weak annihilation, Penguin operators, etc. are still unanswered. Important directions in future work, both on the experimental and theoretical side are identified.

  9. Advances in understanding hypopituitarism

    PubMed Central

    Stieg, Mareike R.; Renner, Ulrich; Stalla, Günter K.; Kopczak, Anna

    2017-01-01

    The understanding of hypopituitarism has increased over the last three years. This review provides an overview of the most important recent findings. Most of the recent research in hypopituitarism has focused on genetics. New diagnostic techniques like next-generation sequencing have led to the description of different genetic mutations causative for congenital dysfunction of the pituitary gland while new molecular mechanisms underlying pituitary ontogenesis have also been described. Furthermore, hypopituitarism may occur because of an impairment of the distinctive vascularization of the pituitary gland, especially by disruption of the long vessel connection between the hypothalamus and the pituitary. Controversial findings have been published on post-traumatic hypopituitarism. Moreover, autoimmunity has been discussed in recent years as a possible reason for hypopituitarism. With the use of new drugs such as ipilimumab, hypopituitarism as a side effect of pharmaceuticals has come into focus. Besides new findings on the pathomechanism of hypopituitarism, there are new diagnostic tools in development, such as new growth hormone stimulants that are currently being tested in clinical trials. Moreover, cortisol measurement in scalp hair is a promising tool for monitoring cortisol levels over time. PMID:28299199

  10. Recent advances in understanding neutrophils

    PubMed Central

    Deniset, Justin F.; Kubes, Paul

    2016-01-01

    Neutrophils have long been regarded as key effectors of the innate immune response during acute inflammation. Recent evidence has revealed a greater functional diversity for these cells than previously appreciated, expanding roles for neutrophils in adaptive immunity and chronic pathologies. In this review, we summarize some of the evolving paradigms in the neutrophil field and highlight key advances that have contributed to our understanding of neutrophil behavior and function in vivo. We examine the concept of neutrophil subsets and polarization, we discuss novel immunomodulatory roles for neutrophils in shaping the immune response, and, finally, we identify technical advances that will further enhance our ability to track the function and fate of neutrophils. PMID:28105328

  11. Advances in understanding begomovirus satellites.

    PubMed

    Zhou, Xueping

    2013-01-01

    Begomoviruses are numerous and geographically widespread viruses that cause devastating diseases in many crops. Monopartite begomoviruses are frequently associated with betasatellites or alphasatellites. Both betasatellite and alphasatellite DNA genomes are approximately half the size of begomovirus DNA genomes. Betasatellites are essential for induction of typical disease symptoms. The βC1 genes encoded by the betasatellites have important roles in symptom induction, in suppression of transcriptional and posttranscriptional gene silencing, and they can affect jasmonic acid responsive genes. Host plants of begomoviruses have evolved diverse innate defense mechanisms against the βC1 protein to counter these challenges. Alphasatellites have been identified mainly in monopartite begomoviruses that associate with betasatellites and have no known contributions to pathogenesis of begomovirus-betasatellite disease complexes. Applications of current molecular tools are facilitating viral diagnosis and the discovery of novel species of geminiviruses and satellite DNAs and are also advancing our understanding of the global diversity and evolution of satellite DNAs.

  12. Recent advances in understanding schizophrenia

    PubMed Central

    Haller, Chiara S.; Padmanabhan, Jaya L.; Lizano, Paulo; Torous, John

    2014-01-01

    Schizophrenia is a highly disabling disorder whose causes remain to be better understood, and treatments have to be improved. However, several recent advances have been made in diagnosis, etiopathology, and treatment. Whereas reliability of diagnosis has improved with operational criteria, including Diagnostic and Statistical Manual of Mental Disorders, (DSM) Fifth Edition, validity of the disease boundaries remains unclear because of substantive overlaps with other psychotic disorders. Recent emphasis on dimensional approaches and translational bio-behavioral research domain criteria may eventually help move toward a neuroscience-based definition of schizophrenia. The etiology of schizophrenia is now thought to be multifactorial, with multiple small-effect and fewer large-effect susceptibility genes interacting with several environmental factors. These factors may lead to developmentally mediated alterations in neuroplasticity, manifesting in a cascade of neurotransmitter and circuit dysfunctions and impaired connectivity with an onset around early adolescence. Such etiopathological understanding has motivated a renewed search for novel pharmacological as well as psychotherapeutic targets. Addressing the core features of the illness, such as cognitive deficits and negative symptoms, and developing hypothesis-driven early interventions and preventive strategies are high-priority goals for the field. Schizophrenia is a severe, chronic mental disorder and is among the most disabling disorders in all of medicine. It is estimated by the National Institute of Mental Health (NIMH) that 2.4 million people over the age of 18 in the US suffer from schizophrenia. This illness typically begins in adolescence and derails the formative goals of school, family, and work, leading to considerable suffering and disability and reduced life expectancy by about 20 years. Treatment outcomes are variable, and some people are successfully treated and reintegrated (i.e. go back to work

  13. Recent advances in understanding dengue

    PubMed Central

    Yacoub, Sophie; Mongkolsapaya, Juthathip; Screaton, Gavin

    2016-01-01

    Dengue is an emerging threat to billions of people worldwide. In the last 20 years, the incidence has increased four-fold and this trend appears to be continuing. Caused by one of four viral serotypes, dengue can present as a wide range of clinical phenotypes with the severe end of the spectrum being defined by a syndrome of capillary leak, coagulopathy, and organ impairment. The pathogenesis of severe disease is thought to be in part immune mediated, but the exact mechanisms remain to be defined. The current treatment of dengue relies on supportive measures with no licensed therapeutics available to date. There have been recent advances in our understanding of a number of areas of dengue research, of which the following will be discussed in this review: the drivers behind the global dengue pandemic, viral structure and epitope binding, risk factors for severe disease and its pathogenesis, as well as the findings of recent clinical trials including therapeutics and vaccines. We conclude with current and future dengue control measures and key areas for future research. PMID:26918159

  14. Understanding bimolecular machines: Theoretical and experimental approaches

    NASA Astrophysics Data System (ADS)

    Goler, Adam Scott

    This dissertation concerns the study of two classes of molecular machines from a physical perspective: enzymes and membrane proteins. Though the functions of these classes of proteins are different, they each represent important test-beds from which new understanding can be developed by the application of different techniques. HIV1 Reverse Transcriptase is an enzyme that performs multiple functions, including reverse transcription of RNA into an RNA/DNA duplex, RNA degradation by the RNaseH domain, and synthesis of dsDNA. These functions allow for the incorporation of the retroviral genes into the host genome. Its catalytic cycle requires repeated large-scale conformational changes fundamental to its mechanism. Motivated by experimental work, these motions were studied theoretically by the application of normal mode analysis. It was observed that the lowest order modes correlate with largest amplitude (low-frequency) motion, which are most likely to be catalytically relevant. Comparisons between normal modes obtained via an elastic network model to those calculated from the essential dynamics of a series of all-atom molecular dynamics simulations show the self-consistency between these calculations. That similar conformational motions are seen between independent theoretical methods reinforces the importance of large-scale subdomain motion for the biochemical action of DNA polymerases in general. Moreover, it was observed that the major subunits of HIV1 Reverse Transcriptase interact quasi-harmonically. The 5HT3A Serotonin receptor and P2X1 receptor, by contrast, are trans-membrane proteins that function as ligand gated ion channels. Such proteins feature a central pore, which allows for the transit of ions necessary for cellular function across a membrane. The pore is opened by the ligation of binding sites on the extracellular portion of different protein subunits. In an attempt to resolve the individual subunits of these membrane proteins beyond the diffraction

  15. Recent advances in understanding vitiligo.

    PubMed

    Manga, Prashiela; Elbuluk, Nada; Orlow, Seth J

    2016-01-01

    Vitiligo, an acquired depigmentation disorder, manifests as white macules on the skin and can cause significant psychological stress and stigmatization. Recent advances have shed light on key components that drive disease onset and progression as well as therapeutic approaches. Vitiligo can be triggered by stress to the melanin pigment-producing cells of the skin, the melanocytes. The triggers, which range from sunburn to mechanical trauma and chemical exposures, ultimately cause an autoimmune response that targets melanocytes, driving progressive skin depigmentation. The most significant progress in our understanding of disease etiology has been made on three fronts: (1) identifying cellular responses to stress, including antioxidant pathways and the unfolded protein response (UPR), as key players in disease onset, (2) characterizing immune responses that target melanocytes and drive disease progression, and (3) identifying major susceptibility genes. The current model for vitiligo pathogenesis postulates that oxidative stress causes cellular disruptions, including interruption of protein maturation in the endoplasmic reticulum (ER), leading to the activation of the UPR and expression of UPR-regulated chemokines such as interleukin 6 (IL-6) and IL-8. These chemokines recruit immune components to the skin, causing melanocytes to be targeted for destruction. Oxidative stress can further increase melanocyte targeting by promoting antigen presentation. Two key components of the autoimmune response that promote disease progression are the interferon (IFN)-γ/CXCL10 axis and IL-17-mediated responses. Several genome-wide association studies support a role for these pathways, with the antioxidant gene NRF2, UPR gene XBP1, and numerous immune-related genes including class I and class II major histocompatibility genes associated with a risk for developing vitiligo. Novel approaches to promote repigmentation in vitiligo are being investigated and may yield effective, long

  16. Recent advances in understanding vitiligo

    PubMed Central

    Manga, Prashiela; Elbuluk, Nada; Orlow, Seth J.

    2016-01-01

    Vitiligo, an acquired depigmentation disorder, manifests as white macules on the skin and can cause significant psychological stress and stigmatization. Recent advances have shed light on key components that drive disease onset and progression as well as therapeutic approaches. Vitiligo can be triggered by stress to the melanin pigment-producing cells of the skin, the melanocytes. The triggers, which range from sunburn to mechanical trauma and chemical exposures, ultimately cause an autoimmune response that targets melanocytes, driving progressive skin depigmentation. The most significant progress in our understanding of disease etiology has been made on three fronts: (1) identifying cellular responses to stress, including antioxidant pathways and the unfolded protein response (UPR), as key players in disease onset, (2) characterizing immune responses that target melanocytes and drive disease progression, and (3) identifying major susceptibility genes. The current model for vitiligo pathogenesis postulates that oxidative stress causes cellular disruptions, including interruption of protein maturation in the endoplasmic reticulum (ER), leading to the activation of the UPR and expression of UPR-regulated chemokines such as interleukin 6 (IL-6) and IL-8. These chemokines recruit immune components to the skin, causing melanocytes to be targeted for destruction. Oxidative stress can further increase melanocyte targeting by promoting antigen presentation. Two key components of the autoimmune response that promote disease progression are the interferon (IFN)-γ/CXCL10 axis and IL-17-mediated responses. Several genome-wide association studies support a role for these pathways, with the antioxidant gene NRF2, UPR gene XBP1, and numerous immune-related genes including class I and class II major histocompatibility genes associated with a risk for developing vitiligo. Novel approaches to promote repigmentation in vitiligo are being investigated and may yield effective, long

  17. Advances in understanding illness anxiety.

    PubMed

    Harding, Kelli J; Skritskaya, Natalia; Doherty, Emily; Fallon, Brian A

    2008-08-01

    Illness anxiety, also known in its more severe form as hypochondriasis, is a debilitating and chronic condition in which normal bodily symptoms are misinterpreted as signs of serious medical illness. Patients suffer with the fear that they are ill despite reassurance to the contrary and often overuse medical services in the process. This article critically evaluates the recent literature on illness anxiety and related, medically unexplained symptoms, highlighting new and interesting findings in the areas of prevalence, classification/diagnosis, management, and evidence-based treatment and new frontiers in understanding illness anxiety, such as brain imaging, neuroimmunology, and cyberchondria.

  18. Recent advances in understanding Streptomyces

    PubMed Central

    Chater, Keith F.

    2016-01-01

    About 2,500 papers dated 2014–2016 were recovered by searching the PubMed database for Streptomyces, which are the richest known source of antibiotics. This review integrates around 100 of these papers in sections dealing with evolution, ecology, pathogenicity, growth and development, stress responses and secondary metabolism, gene expression, and technical advances. Genomic approaches have greatly accelerated progress. For example, it has been definitively shown that interspecies recombination of conserved genes has occurred during evolution, in addition to exchanges of some of the tens of thousands of non-conserved accessory genes. The closeness of the association of Streptomyces with plants, fungi, and insects has become clear and is reflected in the importance of regulators of cellulose and chitin utilisation in overall Streptomyces biology. Interestingly, endogenous cellulose-like glycans are also proving important in hyphal growth and in the clumping that affects industrial fermentations. Nucleotide secondary messengers, including cyclic di-GMP, have been shown to provide key input into developmental processes such as germination and reproductive growth, while late morphological changes during sporulation involve control by phosphorylation. The discovery that nitric oxide is produced endogenously puts a new face on speculative models in which regulatory Wbl proteins (peculiar to actinobacteria) respond to nitric oxide produced in stressful physiological transitions. Some dramatic insights have come from a new model system for Streptomyces developmental biology, Streptomyces venezuelae, including molecular evidence of very close interplay in each of two pairs of regulatory proteins. An extra dimension has been added to the many complexities of the regulation of secondary metabolism by findings of regulatory crosstalk within and between pathways, and even between species, mediated by end products. Among many outcomes from the application of chromosome

  19. Recent advances in understanding Streptomyces.

    PubMed

    Chater, Keith F

    2016-01-01

    About 2,500 papers dated 2014-2016 were recovered by searching the PubMed database for Streptomyces, which are the richest known source of antibiotics. This review integrates around 100 of these papers in sections dealing with evolution, ecology, pathogenicity, growth and development, stress responses and secondary metabolism, gene expression, and technical advances. Genomic approaches have greatly accelerated progress. For example, it has been definitively shown that interspecies recombination of conserved genes has occurred during evolution, in addition to exchanges of some of the tens of thousands of non-conserved accessory genes. The closeness of the association of Streptomyces with plants, fungi, and insects has become clear and is reflected in the importance of regulators of cellulose and chitin utilisation in overall Streptomyces biology. Interestingly, endogenous cellulose-like glycans are also proving important in hyphal growth and in the clumping that affects industrial fermentations. Nucleotide secondary messengers, including cyclic di-GMP, have been shown to provide key input into developmental processes such as germination and reproductive growth, while late morphological changes during sporulation involve control by phosphorylation. The discovery that nitric oxide is produced endogenously puts a new face on speculative models in which regulatory Wbl proteins (peculiar to actinobacteria) respond to nitric oxide produced in stressful physiological transitions. Some dramatic insights have come from a new model system for Streptomyces developmental biology, Streptomyces venezuelae, including molecular evidence of very close interplay in each of two pairs of regulatory proteins. An extra dimension has been added to the many complexities of the regulation of secondary metabolism by findings of regulatory crosstalk within and between pathways, and even between species, mediated by end products. Among many outcomes from the application of chromosome

  20. Recent advances in understanding noroviruses

    PubMed Central

    Bartnicki, Eric; Cunha, Juliana Bragazzi; Kolawole, Abimbola O.; Wobus, Christiane E.

    2017-01-01

    Noroviruses are the leading cause of acute gastroenteritis around the world. An individual living in the United States is estimated to develop norovirus infection five times in his or her lifetime. Despite this, there is currently no antiviral or vaccine to combat the infection, in large part because of the historical lack of cell culture and small animal models. However, the last few years of norovirus research were marked by a number of ground-breaking advances that have overcome technical barriers and uncovered novel aspects of norovirus biology. Foremost among them was the development of two different in vitro culture systems for human noroviruses. Underappreciated was the notion that noroviruses infect cells of the immune system as well as epithelial cells within the gastrointestinal tract and that human norovirus infection of enterocytes requires or is promoted by the presence of bile acids. Furthermore, two proteinaceous receptors are now recognized for murine norovirus, marking the first discovery of a functional receptor for any norovirus. Recent work further points to a role for certain bacteria, including those found in the gut microbiome, as potential modulators of norovirus infection in the host, emphasizing the importance of interactions with organisms from other kingdoms of life for viral pathogenesis. Lastly, we will highlight the adaptation of drop-based microfluidics to norovirus research, as this technology has the potential to reveal novel insights into virus evolution. This review aims to summarize these new findings while also including possible future directions. PMID:28163914

  1. Advances in Understanding the Biosynthesis of Fumonisins

    USDA-ARS?s Scientific Manuscript database

    Fumonisins are a group of economically important mycotoxins that are derived polyketides. Since the cloning of the fumonisin polyketide synthase (PKS) gene from Fusarium verticillioides in 1999, significant advances have been made in understanding the molecular mechanisms for fumonisin biosynthesis...

  2. Development of Improved Microwave Dielectric Materials and Devices using Advanced Experimental and Theoretical Methods

    DTIC Science & Technology

    2008-04-17

    REPORT Development of improved microwave dielectric materials and devices using advanced experimental and theoretical methods 14. ABSTRACT 16. SECURITY... methods Report Title ABSTRACT Our work has made important progress towards developing a fundamental understanding of the microscopic mechanism that causes...electromagnetic Band Gap Filters using advanced ceramic injection molding methods ”, Semiconductor Research Corporation Packaging and Interconnect Summer

  3. Advances in Understanding Air Pollution and CVD.

    PubMed

    Kaufman, Joel D; Spalt, Elizabeth W; Curl, Cynthia L; Hajat, Anjum; Jones, Miranda R; Kim, Sun-Young; Vedal, Sverre; Szpiro, Adam A; Gassett, Amanda; Sheppard, Lianne; Daviglus, Martha L; Adar, Sara D

    2016-09-01

    The MESA Air (Multi-Ethnic Study of Atherosclerosis and Air Pollution) leveraged the platform of the MESA cohort into a prospective longitudinal study of relationships between air pollution and cardiovascular health. MESA Air researchers developed fine-scale, state-of-the-art air pollution exposure models for the MESA Air communities, creating individual exposure estimates for each participant. These models combine cohort-specific exposure monitoring, existing monitoring systems, and an extensive database of geographic and meteorological information. Together with extensive phenotyping in MESA-and adding participants and health measurements to the cohort-MESA Air investigated environmental exposures on a wide range of outcomes. Advances by the MESA Air team included not only a new approach to exposure modeling, but also biostatistical advances in addressing exposure measurement error and temporal confounding. The MESA Air study advanced our understanding of the impact of air pollutants on cardiovascular disease and provided a research platform for advances in environmental epidemiology.

  4. Primary femininity: clinical advances and theoretical ambiguities.

    PubMed

    Kulish, N

    2000-01-01

    This paper examines the use of the term "primary femininity" in current psychoanalytic thinking. The concept of primary femininity arose in reaction to early theories about female sexuality and development; based on a model of male development, these presented problems when applied to females. The author attempts to demonstrate the clinical advances that have resulted from the idea of primary femininity. At the same time she argues that the idea has been used to carry widely differing meanings, and has reflected many writers' differing frames of reference, which range from gender identity through biological traits, object relations, genital anxieties, and bisexuality. Like the terms it originally was intended to replace or augment, it has come to be used reductionistically or loosely. The author warns against its misuse and argues that primary femininity is not a unitary concept, but rather encompasses a related group of ideas about the female body and mind.

  5. Recent theoretical, neural, and clinical advances in sustained attention research.

    PubMed

    Fortenbaugh, Francesca C; DeGutis, Joseph; Esterman, Michael

    2017-03-05

    Models of attention often distinguish among attention subtypes, with classic models separating orienting, switching, and sustaining functions. Compared with other forms of attention, the neurophysiological basis of sustaining attention has received far less notice, yet it is known that momentary failures of sustained attention can have far-ranging negative effects in healthy individuals, and lasting sustained attention deficits are pervasive in clinical populations. In recent years, however, there has been increased interest in characterizing moment-to-moment fluctuations in sustained attention, in addition to the overall vigilance decrement, and understanding how these neurocognitive systems change over the life span and across various clinical populations. The use of novel neuroimaging paradigms and statistical approaches has allowed for better characterization of the neural networks supporting sustained attention and has highlighted dynamic interactions within and across multiple distributed networks that predict behavioral performance. These advances have also provided potential biomarkers to identify individuals with sustained attention deficits. These findings have led to new theoretical models explaining why sustaining focused attention is a challenge for individuals and form the basis for the next generation of sustained attention research, which seeks to accurately diagnose and develop theoretically driven treatments for sustained attention deficits that affect a variety of clinical populations.

  6. Recent advances in understanding and managing asthma

    PubMed Central

    Loo, Su-Ling; Wark, Peter A.B.

    2016-01-01

    This review highlights the important articles published in the area of asthma research from January 2015 to July 2016. In basic science, significant advances have been made in understanding the link between the innate immune response and type II acquired immune responses in asthma and the role of the airway epithelium. Novel information continues to emerge with regard to the pathogenesis and heterogeneity of severe asthma. There have been important translational clinical trials in the areas of childhood asthma, treatment of allergy to improve asthma outcomes, and improving drug delivery to optimize the management of asthma. In addition, there are increasing data concerning the application of biological agents to the management of severe asthma. This body of work discusses the most notable advances in the understanding and management of asthma. PMID:27610226

  7. Recent advances in understanding eosinophil biology.

    PubMed

    Klion, Amy

    2017-01-01

    With the advent of novel therapies targeting eosinophils, there has been renewed interest in understanding the basic biology of this unique cell. In this context, murine models and human studies have continued to highlight the role of the eosinophil in homeostatic functions and immunoregulation. This review will focus on recent advances in our understanding of eosinophil biology that are likely to have important consequences on the development and consequences of eosinophil-targeted therapies. Given the breadth of the topic, the discussion will be limited to three areas of interest: the eosinophil life cycle, eosinophil heterogeneity, and mechanisms of cell-cell communication.

  8. Understanding Literacy: Theoretical Foundations for Research in Media Ecology.

    ERIC Educational Resources Information Center

    Ramos, Lori

    2000-01-01

    Reviews the major scholarship of Harold Innis, Eric Havelock, Marshall McLuhan, Jack Goody, Walter Ong and Elizabeth Eisenstein, as they focused on the development of writing systems, and later, printing. Discusses how their theoretical frameworks are central to understanding media ecology, an emerging field of interdisciplinary study for…

  9. Recent advances in managing and understanding uveitis

    PubMed Central

    Chen, Shih-Chou; Sheu, Shwu-Jiuan

    2017-01-01

    Uveitis is a sight-threatening disease entity with intraocular inflammation that arises from various causes. It mainly affects working-age individuals and may lead to irreversible visual loss if not treated properly in a timely manner. This article reviews recent advances in the management and understanding of uveitis since 2014, including treatment with new immunosuppressive therapies that use biological agents, local therapy with steroid implants, and imaging studies for the evaluation of uveitis. PMID:28357059

  10. Patients' understanding and use of advance directives.

    PubMed Central

    Jacobson, J A; White, B E; Battin, M P; Francis, L P; Green, D J; Kasworm, E S

    1994-01-01

    The Patient Self-Determination Act was implemented in December 1991. Before and after its implementation, we used a structured interview of 302 randomly selected patients to determine their awareness, understanding, and use of advance directives. Implementation of the Act did not have a major effect on these. Although more than 90% of patients were aware of the living will, only about a third selected the correct definition or the correct circumstances in which it applied, and less than 20% of patients had completed one. About a third of patients were aware of a Durable Power of Attorney for Health Care and chose the correct definition, and about half identified the correct circumstances in which it applies; less than 10% had completed such a document. Surprisingly, patients who said they had completed advance directives did not demonstrate better understanding of these documents. Our results indicate that many patients, including some who have completed advance directives, do not fully understand them. It may be unwise to regard these documents as carefully considered, compelling statements of patients' preferences. Appropriate responses to our findings include increased public education, revising state statutes to bring them into congruence with public perception, and expanding the dialogue between physicians and patients. PMID:8191755

  11. Recent advances in understanding and managing gout.

    PubMed

    Igel, Talia F; Krasnokutsky, Svetlana; Pillinger, Michael H

    2017-01-01

    Gout is the most common crystal arthropathy and the leading cause of inflammatory arthritis. It is associated with functional impairment and, for many, a diminished health-related quality of life. Numerous studies have demonstrated the impact of gout and its associated conditions on patient morbidity and mortality. Unfortunately, gout remains under-diagnosed and under-treated in the general community. Despite major advances in treatment strategies, as many as 90% of patients with gout are poorly controlled or improperly managed and their hyperuricemia and recurrent flares continue. The introduction of novel urate-lowering therapies, new imaging modalities, and a deeper understanding of the pathogenesis of gout raise the possibility of better gout care and improved patient outcomes. Here, we spotlight recent advances in the diagnosis and management of gout and discuss novel therapeutics in gout treatment.

  12. Recent advances in understanding and managing gout

    PubMed Central

    Igel, Talia F.; Krasnokutsky, Svetlana; Pillinger, Michael H.

    2017-01-01

    Gout is the most common crystal arthropathy and the leading cause of inflammatory arthritis. It is associated with functional impairment and, for many, a diminished health-related quality of life. Numerous studies have demonstrated the impact of gout and its associated conditions on patient morbidity and mortality. Unfortunately, gout remains under-diagnosed and under-treated in the general community. Despite major advances in treatment strategies, as many as 90% of patients with gout are poorly controlled or improperly managed and their hyperuricemia and recurrent flares continue. The introduction of novel urate-lowering therapies, new imaging modalities, and a deeper understanding of the pathogenesis of gout raise the possibility of better gout care and improved patient outcomes. Here, we spotlight recent advances in the diagnosis and management of gout and discuss novel therapeutics in gout treatment. PMID:28357052

  13. Recent advances in understanding apicomplexan parasites

    PubMed Central

    Seeber, Frank; Steinfelder, Svenja

    2016-01-01

    Intracellular single-celled parasites belonging to the large phylum Apicomplexa are amongst the most prevalent and morbidity-causing pathogens worldwide. In this review, we highlight a few of the many recent advances in the field that helped to clarify some important aspects of their fascinating biology and interaction with their hosts. Plasmodium falciparum causes malaria, and thus the recent emergence of resistance against the currently used drug combinations based on artemisinin has been of major interest for the scientific community. It resulted in great advances in understanding the resistance mechanisms that can hopefully be translated into altered future drug regimens. Apicomplexa are also experts in host cell manipulation and immune evasion. Toxoplasma gondii and Theileria sp., besides Plasmodium sp., are species that secrete effector molecules into the host cell to reach this aim. The underlying molecular mechanisms for how these proteins are trafficked to the host cytosol ( T. gondii and Plasmodium) and how a secreted protein can immortalize the host cell ( Theileria sp.) have been illuminated recently. Moreover, how such secreted proteins affect the host innate immune responses against T. gondii and the liver stages of Plasmodium has also been unraveled at the genetic and molecular level, leading to unexpected insights. Methodological advances in metabolomics and molecular biology have been instrumental to solving some fundamental puzzles of mitochondrial carbon metabolism in Apicomplexa. Also, for the first time, the generation of stably transfected Cryptosporidium parasites was achieved, which opens up a wide variety of experimental possibilities for this understudied, important apicomplexan pathogen. PMID:27347391

  14. Advancing Drought Understanding, Monitoring and Prediction

    NASA Technical Reports Server (NTRS)

    Mariotti, Annarita; Schubert, Siegfried D.; Mo, Kingtse; Peters-Lidard, Christa; Wood, Andy; Pulwarty, Roger; Huang, Jin; Barrie, Dan

    2013-01-01

    Having the capacity to monitor droughts in near-real time and providing accurate drought prediction from weeks to seasons in advance can greatly reduce the severity of social and economic damage caused by drought, a leading natural hazard for North America. The congressional mandate to establish the National Integrated Drought Information System (NIDIS; Public Law 109-430) in 2006 was a major impulse to develop, integrate, and provide drought information to meet the challenges posed by this hazard. Significant progress has been made on many fronts. On the research front, efforts by the broad scientific community have resulted in improved understanding of North American droughts and improved monitoring and forecasting tools. We now have a better understanding of the droughts of the twentieth century including the 1930s "Dust Bowl"; we have developed a broader array of tools and datasets that enhance the official North American Drought Monitor based on different methodologies such as state-of-the-art land surface modeling (e.g., the North American Land Data Assimilation System) and remote sensing (e.g., the evaporative stress index) to better characterize the occurrence and severity of drought in its multiple manifestations. In addition, we have new tools for drought prediction [including the new National Centers for Environmental Prediction (NCEP) Climate Forecast System, version 2, for operational prediction and an experimental National Multimodel Ensemble] and have explored diverse methodologies including ensemble hydrologic prediction approaches. Broad NIDIS-inspired progress is influencing the development of a Global Drought Information System (GDIS) under the auspices of the World Climate Research Program. Despite these advances, current drought monitoring and forecasting capabilities still fall short of users' needs, especially the need for skillful and reliable drought forecasts at regional and local scales. To tackle this outstanding challenging problem

  15. Recent advances in understanding & managing male infertility

    PubMed Central

    Bieniek, Jared M.; Lo, Kirk C.

    2016-01-01

    Male infertility remains a struggle to definitively diagnose and treat with many men labelled as “idiopathic infertility” and eventually requiring assisted reproductive techniques.  Along those lines, research groups are continuing to explore current social and environmental factors, including the obesity epidemic, and their effects on male fertility potential.  Novel biomarkers of natural fertility status and azoospermia etiology have additionally seen recent attention with ACRV1 and TEX101/ECM1 assays either currently or soon to be commercially available.  Despite these advancements, however, medical treatment options have seen little progress.  Though surgical therapies have similarly seen little transformation, groups are exploring the use of testicular sperm for couples with elevated sperm DNA fragmentation and either planned or previously failed IVF/ICSI.  Concerted collaborative efforts will be needed as we move forward to better understand the challenges men face when struggling to conceive. PMID:27990271

  16. Recent advances in understanding antitumor immunity

    PubMed Central

    Munhoz, Rodrigo Ramella; Postow, Michael Andrew

    2016-01-01

    The term “antitumor immunity” refers to innate and adaptive immune responses which lead to tumor control. Turning the immune system into a destructive force against tumors has been achieved in a broad range of human cancers with the use of non-specific immunotherapies, vaccines, adoptive-cell therapy, and, more recently with significant success, through blockade of immune checkpoints. Nevertheless, the efficacy of these approaches is not universal, and tools to identify long-term responders and primarily refractory patients are warranted. In this article, we review recent advances in understanding the complex mechanisms of antitumor immunity and how these developments can be used to address open questions in a setting of growing clinical indications for the use of immunotherapy. PMID:27803807

  17. Recent advances in understanding multiple myeloma

    PubMed Central

    Dhakal, Binod; Girnius, Saulius; Hari, Parameswaran

    2016-01-01

    There have been major recent advancements in the understanding and management of multiple myeloma. Diagnostic criteria have been revised and former ultra-high-risk smoldering multiple myeloma is now considered multiple myeloma in need of treatment. Understanding clonal progression, evolution, and tides not only has helped elucidate the disease behavior but might help expand therapeutic choices in order to select appropriate treatment for patients. Unprecedented response rates with modern triplet induction therapies containing proteasome inhibitor and immunomodulators have made this approach standard for initial treatment. The US Food and Drug Administration approved four new drugs (two targeted antibodies and two oral agents) in 2015 in relapsed/refractory multiple myeloma and these drugs along with the other already-available drugs have now increased the choices of regimens. Even drugs without single-agent activity, such as panobinostat and elotuzumab, have an important role, especially in the proteasome inhibitor refractory setting. Recent studies done in the context of novel agent induction suggest that high-dose therapy followed by autologous transplant continues to improve response rates and progression-free survival, thus underscoring their role in transplant-eligible patients. Evolving paradigms in the treatment of multiple myeloma include newer promising immune approaches, such as adoptive cellular therapies, vaccines, or antibody-based immune manipulations. Though multiple myeloma is still considered incurable, it is clear that with the improved understanding of disease biology and clonal architecture of relapse combined with the availability of multi-targeted approaches, we are ever closer to a lasting cure or transformation into indolent and long-lasting disease courses or both. PMID:27610224

  18. Recent advances in understanding multiple myeloma.

    PubMed

    Dhakal, Binod; Girnius, Saulius; Hari, Parameswaran

    2016-01-01

    There have been major recent advancements in the understanding and management of multiple myeloma. Diagnostic criteria have been revised and former ultra-high-risk smoldering multiple myeloma is now considered multiple myeloma in need of treatment. Understanding clonal progression, evolution, and tides not only has helped elucidate the disease behavior but might help expand therapeutic choices in order to select appropriate treatment for patients. Unprecedented response rates with modern triplet induction therapies containing proteasome inhibitor and immunomodulators have made this approach standard for initial treatment. The US Food and Drug Administration approved four new drugs (two targeted antibodies and two oral agents) in 2015 in relapsed/refractory multiple myeloma and these drugs along with the other already-available drugs have now increased the choices of regimens. Even drugs without single-agent activity, such as panobinostat and elotuzumab, have an important role, especially in the proteasome inhibitor refractory setting. Recent studies done in the context of novel agent induction suggest that high-dose therapy followed by autologous transplant continues to improve response rates and progression-free survival, thus underscoring their role in transplant-eligible patients. Evolving paradigms in the treatment of multiple myeloma include newer promising immune approaches, such as adoptive cellular therapies, vaccines, or antibody-based immune manipulations. Though multiple myeloma is still considered incurable, it is clear that with the improved understanding of disease biology and clonal architecture of relapse combined with the availability of multi-targeted approaches, we are ever closer to a lasting cure or transformation into indolent and long-lasting disease courses or both.

  19. Advances in understanding mechanisms underpinning lithium-air batteries

    NASA Astrophysics Data System (ADS)

    Aurbach, Doron; McCloskey, Bryan D.; Nazar, Linda F.; Bruce, Peter G.

    2016-09-01

    The rechargeable lithium-air battery has the highest theoretical specific energy of any rechargeable battery and could transform energy storage if a practical device could be realized. At the fundamental level, little was known about the reactions and processes that take place in the battery, representing a significant barrier to progress. Here, we review recent advances in understanding the chemistry and electrochemistry that govern the operation of the lithium-air battery, especially the reactions at the cathode. The mechanisms of O2 reduction to Li2O2 on discharge and the reverse process on charge are discussed in detail, as are their consequences for the rate and capacity of the battery. The various parasitic reactions involving the cathode and electrolyte during discharge and charge are also considered. We also provide views on understanding the stability of the cathode and electrolyte and examine design principles for better lithium-air batteries.

  20. Advances in understanding drug-induced neuropathies.

    PubMed

    Peltier, Amanda C; Russell, James W

    2006-01-01

    Many commonly used medications have neurotoxic adverse effects; the most common of these is peripheral neuropathy. Neuropathy can be a dose-limiting adverse effect for many medications used in life-threatening conditions, such as malignancy and HIV-related disease. Epidemiological evidence supports previous case reports of HMG-CoA reductase inhibitors (or 'statins') causing an axonal sensorimotor neuropathy or a purely small-fibre neuropathy in some patients. The neuropathy improves when the medication is withdrawn. Despite the association between HMG-CoA reductase inhibitors and neuropathy, the risk is low compared with the significant vascular protective benefits. Oxaliplatin, a new platinum chemotherapy agent designed to have fewer adverse effects than other such agents, has been shown to cause a transient initial dysaesthesia in addition to an axonal polyneuropathy. Thalidomide, an old therapy currently being utilised for new therapeutic indications (e.g. treatment of haematological malignancies), is associated with a painful, axonal sensorimotor neuropathy that does not improve on withdrawal of the drug. Nucleoside reverse transcriptase inhibitors are important components of highly active antiretroviral therapy, but are associated with a sensory neuropathy that is likely to be due to a direct effect of these drugs on mitochondrial DNA replication. New research demonstrates that lactate levels may help discriminate between neuropathy caused by nucleoside analogues and HIV-induced neuropathy. Understanding the mechanism of drug-induced neuropathy has led to advances in preventing this disabling condition.

  1. Recent advances in understanding idiopathic pulmonary fibrosis

    PubMed Central

    Daccord, Cécile; Maher, Toby M.

    2016-01-01

    Despite major research efforts leading to the recent approval of pirfenidone and nintedanib, the dismal prognosis of idiopathic pulmonary fibrosis (IPF) remains unchanged. The elaboration of international diagnostic criteria and disease stratification models based on clinical, physiological, radiological, and histopathological features has improved the accuracy of IPF diagnosis and prediction of mortality risk. Nevertheless, given the marked heterogeneity in clinical phenotype and the considerable overlap of IPF with other fibrotic interstitial lung diseases (ILDs), about 10% of cases of pulmonary fibrosis remain unclassifiable. Moreover, currently available tools fail to detect early IPF, predict the highly variable course of the disease, and assess response to antifibrotic drugs. Recent advances in understanding the multiple interrelated pathogenic pathways underlying IPF have identified various molecular phenotypes resulting from complex interactions among genetic, epigenetic, transcriptional, post-transcriptional, metabolic, and environmental factors. These different disease endotypes appear to confer variable susceptibility to the condition, differing risks of rapid progression, and, possibly, altered responses to therapy. The development and validation of diagnostic and prognostic biomarkers are necessary to enable a more precise and earlier diagnosis of IPF and to improve prediction of future disease behaviour. The availability of approved antifibrotic therapies together with potential new drugs currently under evaluation also highlights the need for biomarkers able to predict and assess treatment responsiveness, thereby allowing individualised treatment based on risk of progression and drug response. This approach of disease stratification and personalised medicine is already used in the routine management of many cancers and provides a potential road map for guiding clinical care in IPF. PMID:27303645

  2. [Advance Directives: theoretical concept and practical significance in the USA].

    PubMed

    Vollmann, J; Pfaff, M

    2003-07-04

    The article examines on the basic of empirical data the discrepancy between the theoretical demand and the practical role of advance directives. Often advance directives have no influence on medical decision-making in clinical care of critically ill patients. The vague language of the widely used standard living wills and the lack of physician-patient communication in the process of delivering an advance directives are contributing factors. However, many physicians even disregard patients' preferences in concrete and meaningful living wills at the end of life. Besides the lack of information many even seriously ill patients do not deliver an advance because they misjudge their medical prognosis and life expectancy. Often the communication between patients and doctors are blocked because they expect from the each other the first step to talk about end of life decisions and advance directives. In this context physicians claim lack of time, training in communication skills and their discomfort in talking about death and dying with their patients.

  3. A NETWORK-THEORETICAL APPROACH TO UNDERSTANDING INTERSTELLAR CHEMISTRY

    SciTech Connect

    Jolley, Craig C.; Douglas, Trevor

    2010-10-20

    Recent years have seen dramatic advances in computational models of chemical processes in the interstellar medium (ISM). Typically, these models have been used to calculate changes in chemical abundances with time; the calculated abundances can then be compared with chemical abundances derived from observations. In this study, the output from an astrochemical simulation has been used to generate directed graphs with weighted edges; these have been analyzed with the tools of network theory to uncover whole-network properties of reaction systems in dark molecular clouds. The results allow the development of a model in which global network properties can be rationalized in terms of the basic physical properties of the reaction system. The ISM network exhibits an exponential degree distribution, which is likely to be a generic feature of chemical networks involving a broad range of reaction rate constants. While species abundances span several orders of magnitude, the formation and destruction rates for most species are approximately balanced-departures from this rule indicate species (such as CO) that play a critical role in shaping the dynamics of the system. Future theoretical or observational studies focusing on individual molecular species will be able to situate them in terms of their role in the complete system or quantify the degree to which they deviate from the typical system behavior.

  4. Advancing Future Network Science through Content Understanding

    DTIC Science & Technology

    2014-05-01

    efficiently in any language on any compute cluster and analyze virtually any content when using their D4M (Dynamic Distributed Dimensional Data Model...others who go on to demonstrate that cognitive radios, software defined networks, and other cyber- virtualizations will have to not only support but...Dr. Daniel McFarlane is Principal Research Engineer and LM Fellow Emeritus in the Informatics Lab at Lockheed Martin Advanced Technology

  5. Advances in understanding and managing bullous pemphigoid

    PubMed Central

    Zhao, Cathy Y.; Murrell, Dedee F.

    2015-01-01

    Bullous pemphigoid (BP) is the commonest subtype of autoimmune blistering disease in most countries of the world. It occurs most frequently in elderly patients and is characterised clinically by large, tense blisters in the skin preceded by urticarial plaques and pruritus. Immunopathologically, it is characterised by autoantibodies directed against the 180 kD antigen (BP180) and the 230 kD antigen (BP230). New knowledge regarding BP is being continually uncovered. This article reviews the recent advances in BP, including newer diagnostic tests, standardised outcome measures and emerging therapeutic options, as well as the evidence supporting their use. PMID:26918143

  6. Recent advances in understanding and treating vasculitis

    PubMed Central

    Koster, Matthew J.; Warrington, Kenneth J.

    2016-01-01

    Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) are near universally fatal conditions if untreated. Although effective therapeutic options are available for these diseases, treatment regimens are associated with both short- and long-term adverse effects. The recent identification of effective B-cell-targeted therapy with an anti-CD20 monoclonal antibody has transformed the treatment landscape of AAV. Questions, nevertheless, remain regarding the appropriate timing, dose, frequency, duration, and long-term effects of treatment. The aim of this article is to provide an overview of the current information, recent advances, ongoing clinical trials, and future treatment possibilities in AAV. PMID:27347395

  7. Recent advances in understanding and managing chordomas

    PubMed Central

    Youssef, Carl; Aoun, Salah; Moreno, Jessica R.; Bagley, Carlos A.

    2016-01-01

    Chordomas are rare primary bone tumors arising from embryonic remnants of the notochord. They are slow-growing, locally aggressive, and destructive and typically involve the axial skeleton. Genetic studies have identified several mutations implicated in the pathogenesis of these tumors. Treatment poses a challenge given their insidious progression, degree of local invasion at presentation, and high recurrence rate. They tend to respond poorly to conventional chemotherapy and radiation. This makes radical resection the mainstay of their treatment. Recent advances in targeted chemotherapy and focused particle beam radiation, however, have improved the management and prognosis of these tumors. PMID:28105324

  8. Understanding-misunderstanding: a philosophical and theoretical exploration.

    PubMed

    Condon, Barbara Backer

    2010-10-01

    Understanding-misunderstanding is an intrinsic part of being human. It is understanding that might be said to underscore all communication. This article is an in-depth exploration of the philosophical views regarding human understanding from some of the greatest philosophers in history, and a glimpse into the disciplines of sociology, psychology, and nursing in their views on human understanding or related concepts. Human understanding-misunderstanding is supported in the literature as a paradox--one that continues to be mysterious and illimitable. In fact, it is the belief of this author, in every human encounter, one cannot not understand-misunderstand.

  9. Advances in understanding paternally transmitted Chromosomal Abnormalities

    SciTech Connect

    Marchetti, F; Sloter, E; Wyrobek, A J

    2001-03-01

    Multicolor FISH has been adapted for detecting the major types of chromosomal abnormalities in human sperm including aneuploidies for clinically-relevant chromosomes, chromosomal aberrations including breaks and rearrangements, and other numerical abnormalities. The various sperm FISH assays have been used to evaluate healthy men, men of advanced age, and men who have received mutagenic cancer therapy. The mouse has also been used as a model to investigate the mechanism of paternally transmitted genetic damage. Sperm FISH for the mouse has been used to detect chromosomally abnormal mouse sperm, while the PAINT/DAPI analysis of mouse zygotes has been used to evaluate the types of chromosomal defects that can be paternally transmitted to the embryo and their effects on embryonic development.

  10. Recent advances in understanding ichthyosis pathogenesis

    PubMed Central

    Marukian, Nareh V.; Choate, Keith A.

    2016-01-01

    The ichthyoses, also known as disorders of keratinization (DOK), encompass a heterogeneous group of skin diseases linked by the common finding of abnormal barrier function, which initiates a default compensatory pathway of hyperproliferation, resulting in the characteristic clinical manifestation of localized and/or generalized scaling. Additional cutaneous findings frequently seen in ichthyoses include generalized xerosis, erythroderma, palmoplantar keratoderma, hypohydrosis, and recurrent infections. In 2009, the Ichthyosis Consensus Conference established a classification consensus for DOK based on pathophysiology, clinical manifestations, and mode of inheritance. This nomenclature system divides DOK into two main groups: nonsyndromic forms, with clinical findings limited to the skin, and syndromic forms, with involvement of additional organ systems. Advances in next-generation sequencing technology have allowed for more rapid and cost-effective genetic analysis, leading to the identification of novel, rare mutations that cause DOK, many of which represent phenotypic expansion. This review focuses on new findings in syndromic and nonsyndromic ichthyoses, with emphasis on novel genetic discoveries that provide insight into disease pathogenesis. PMID:27408699

  11. Advances In Understanding Solar And Stellar Flares

    NASA Astrophysics Data System (ADS)

    Kowalski, Adam F.

    2016-07-01

    Flares result from the sudden reconnection and relaxation of magnetic fields in the coronae of stellar atmospheres. The highly dynamic atmospheric response produces radiation across the electromagnetic spectrum, from the radio to X-rays, on a range of timescales, from seconds to days. New high resolution data of solar flares have revealed the intrinsic spatial properties of the flaring chromosphere, which is thought to be where the majority of the flare energy is released as radiation in the optical and near-UV continua and emission lines. New data of stellar flares have revealed the detailed properties of the broadband (white-light) continuum emission, which provides straightforward constraints for models of the transformation of stored magnetic energy in the corona into thermal energy of the lower atmosphere. In this talk, we discuss the physical processes that produce several important spectral phenomena in the near-ultraviolet and optical as revealed from new radiative-hydrodynamic models of flares on the Sun and low mass stars. We present recent progress with high-flux nonthermal electron beams in reproducing the observed optical continuum color temperature of T 10,000 K and the Balmer jump properties in the near-ultraviolet. These beams produce dense, heated chromospheric condensations, which can explain the shape and strength of the continuum emission in M dwarf flares and the red-wing asymmetries in the chromospheric emission lines in recent observations of solar flares from the Interface Region Imaging Spectrograph. Current theoretical challenges and future modeling directions will be discussed, as well as observational synergies between solar and stellar flares.

  12. ADVANCES IN UNDERSTANDING THE LEUKEMIA MICROENVIRONMENT

    PubMed Central

    Tabe, Yoko; Konopleva, Marina

    2015-01-01

    SUMMARY Dynamic interactions between leukemic cells and cells of the bone marrow are a feature of hematological malignancies. Two distinct microenvironmental niches in the bone marrow, the “osteoblastic (endosteal)” and “vascular” niches, provide a sanctuary for subpopulations of leukemic cells to evade chemotherapy-induced death and allow acquisition of a drug-resistance. Key components of the bone marrow microenvironment as a home for normal hematopoietic stem cells and the leukemia stem cell niches, and the molecular pathways critical for microenvironment/leukemia interactions via cytokines, chemokines, and adhesion molecules as well as hypoxic conditions, are described in this review. Finally, the genetic abnormalities of leukemia-associated stroma are discussed. Further understanding of the contribution of the bone marrow niche to the process of leukemogenesis may provide new targets that allow destruction of leukemia stem cells without adversely affecting normal stem cell self-renewal. PMID:24405087

  13. Advances in understanding the leukaemia microenvironment.

    PubMed

    Tabe, Yoko; Konopleva, Marina

    2014-03-01

    Dynamic interactions between leukaemic cells and cells of the bone marrow are a feature of haematological malignancies. Two distinct microenvironmental niches in the bone marrow, the 'osteoblastic (endosteal)' and 'vascular' niches, provide a sanctuary for subpopulations of leukaemic cells to evade chemotherapy-induced death and allow acquisition of drug resistance. Key components of the bone marrow microenvironment as a home for normal haematopoietic stem cells and the leukaemia stem cell niches, and the molecular pathways critical for microenvironment/leukaemia interactions via cytokines, chemokines and adhesion molecules as well as hypoxic conditions, are described in this review. Finally, the genetic abnormalities of leukaemia-associated stroma are discussed. Further understanding of the contribution of the bone marrow niche to the process of leukaemogenesis may provide new targets that allow destruction of leukaemia stem cells without adversely affecting normal stem cell self-renewal. © 2014 John Wiley & Sons Ltd.

  14. Recent advances in understanding provoked vestibulodynia

    PubMed Central

    Lev-Sagie, Ahinoam; Witkin, Steven S.

    2016-01-01

    Vulvodynia refers to pain in the vulva of at least 3 months’ duration in the absence of a recognized underlying cause. Provoked, localized vestibulodynia is the term used to describe superficial pain confined to the vulvar vestibule, provoked by touch. This review will focus on provoked vestibulodynia with regard to its suggested causative factors and will discuss the role of inflammation, vulvovaginal infections, mucosal nerve fiber proliferation, hormonal associations, central pain mechanisms, pelvic floor muscle dysfunction, and genetic factors. Clinical observations, epidemiological studies, and data from basic research emphasize the heterogeneity of vulvar pain syndromes. There is a critical need to perform prospective, longitudinal studies that will allow better diagnostic criteria and subgrouping of patients that would lead to improvements in our understanding of provoked vestibulodynia and its treatment. PMID:27853523

  15. Advances in understanding hydration of Portland cement

    SciTech Connect

    Scrivener, Karen L.; Juilland, Patrick; Monteiro, Paulo J.M.

    2015-12-15

    Progress in understanding hydration is summarized. Evidence supports the geochemistry dissolution theory as an explanation for the induction period, in preference to the inhibiting layer theory. The growth of C–S–H is the principal factor controlling the main heat evolution peak. Electron microscopy indicates that C–S–H “needles” grow from the surface of grains. At the peak, the surface is covered, but deceleration cannot be attributed to diffusion control. The shoulder peak comes from renewed reaction of C{sub 3}A after depletion of sulfate in solution, but release of sulfate absorbed on C–S–H means that ettringite continues to form. After several days space becomes the major factor controlling hydration. The use of new analytical technique is improving our knowledge of the action of superplasticizers and leading to the design of molecules for different applications. Atomistic modeling is becoming a topic of increasing interest. Recent publications in this area are reviewed.

  16. Advances in understanding and treating ADHD

    PubMed Central

    2011-01-01

    Attention deficit hyperactivity disorder (ADHD) is a neurocognitive behavioral developmental disorder most commonly seen in childhood and adolescence, which often extends to the adult years. Relative to a decade ago, there has been extensive research into understanding the factors underlying ADHD, leading to far more treatment options available for both adolescents and adults with this disorder. Novel stimulant formulations have made it possible to tailor treatment to the duration of efficacy required by patients, and to help mitigate the potential for abuse, misuse and diversion. Several new non-stimulant options have also emerged in the past few years. Among these, cognitive behavioral interventions have proven popular in the treatment of adult ADHD, especially within the adult population who cannot or will not use medications, along with the many medication-treated patients who continue to show residual disability. PMID:21658285

  17. Advances in Understanding Decadal Climate Variability

    NASA Technical Reports Server (NTRS)

    Busalaacchi, Antonio J.

    1998-01-01

    Recently, a joint Brazil-France-U.S. program, known as PIRATA (Pilot Research moored Array in the Tropical Atlantic), was proposed to begin the deployment of moored measurement platforms in the tropical Atlantic in order to enhance the existing observational data base and subsequent understanding of the processes by which the ocean and atmosphere couple in key regions of the tropical Atlantic Ocean. Empirical studies have suggested that there are strong relationships between tropical Atlantic upper ocean variability, SST, ocean-atmosphere coupling and regional climate variability. During the early 1980's a coordinated set of surface wind, subsurface thermal structure, and subsurface current observations were obtained as part of the U.S.-France SEQUAL- FOCAL process experiment designed to observe the seasonal response of the tropical Atlantic Ocean to surface forcing. Since that time, however, the observational data base for the tropical Atlantic Ocean has disintegrated to a few shiptracks measuring ocean temperatures and a small collection of tide gauge stations measuring sea level. A more comprehensive set of observations, modeling and empirical studies is now in order to make progress on understanding the regional climate variability. The proposed PIRATA program will use mooring platforms similar to the tropical Pacific Ocean TAO array to measure surface fluxes of momentum and heat and the corresponding changes in the upper ocean thermal structure. It is anticipated that the oceanic data from this monitoring array will also be used in a predictive mode for initialization studies of regional coupled climate models. Of particular interest are zonal and meridional modes of ocean-atmosphere variability within the tropical Atlantic basin that have significant impacts on the regional climate of the bordering continents.

  18. Advances in Understanding Decadal Climate Variability

    NASA Technical Reports Server (NTRS)

    Busalacchi, Antonio J.

    1999-01-01

    Recently, a joint Brazil-France-U.S. program, known as PIRATA (Pilot Research moored Array in the Tropical Atlantic), was proposed to begin the deployment of moored measurement platforms in the tropical Atlantic in order to enhance the existing observational data base and subsequent understanding of the processes by which the ocean and atmosphere couple in key regions of the tropical Atlantic Ocean. Empirical studies have suggested that there are strong relationships between tropical Atlantic upper ocean variability, SST, ocean-atmosphere coupling and regional climate variability. During the early 1980's a coordinated set of surface wind, subsurface thermal structure, and subsurface current observations were obtained as part of the U.S.-France SEQUAL-FOCAL process experiment designed to observe the seasonal response of the tropical Atlantic Ocean to surface forcing. Since that time, however, the observational data base for the tropical Atlantic Ocean has disintegrated to a few ship-tracks measuring ocean temperatures and a small collection of tide gauge stations measuring sea level. A more comprehensive set of observations, modeling and empirical studies is now in order to make progress on understanding the regional climate variability. The proposed PIRATA program will use mooring platforms similar to the tropical Pacific Ocean TAO array to measure surface fluxes of momentum and heat and the corresponding changes in the upper ocean thermal structure. It is anticipated that the oceanic data from this monitoring array will also be used in a predictive mode for initialization studies of regional coupled climate models. Of particular interest are zonal and meridional modes of ocean-atmosphere variability within the tropical Atlantic basin that have significant impacts on the regional climate of the bordering continents.

  19. Advances in Understanding Decadal Climate Variability

    NASA Technical Reports Server (NTRS)

    Busalacchi, Antonio J.

    1999-01-01

    Recently, a joint Brazil-France-U.S. program, known as PIRATA (Pilot Research moored Array in the Tropical Atlantic), was proposed to begin the deployment of moored measurement platforms in the tropical Atlantic in order to enhance the existing observational data base and subsequent understanding of the processes by which the ocean and atmosphere couple in key regions of the tropical Atlantic Ocean. Empirical studies have suggested that there are strong relationships between tropical Atlantic upper ocean variability, SST, ocean-atmosphere coupling and regional climate variability. During the early 1980's a coordinated set of surface wind, subsurface thermal structure, and subsurface current observations were obtained as part of the U.S.-France SEQUAL-FOCAL process experiment designed to observe the seasonal response of the tropical Atlantic Ocean to surface forcing. Since that time, however, the observational data base for the tropical Atlantic Ocean has disintegrated to a few ship-tracks measuring ocean temperatures and a small collection of tide gauge stations measuring sea level. A more comprehensive set of observations, modeling and empirical studies is now in order to make progress on understanding the regional climate variability. The proposed PIRATA program will use mooring platforms similar to the tropical Pacific Ocean TAO array to measure surface fluxes of momentum and heat and the corresponding changes in the upper ocean thermal structure. It is anticipated that the oceanic data from this monitoring array will also be used in a predictive mode for initialization studies of regional coupled climate models. Of particular interest are zonal and meridional modes of ocean-atmosphere variability within the tropical Atlantic basin that have significant impacts on the regional climate of the bordering continents.

  20. Advances in Understanding Decadal Climate Variability

    NASA Technical Reports Server (NTRS)

    Busalaacchi, Antonio J.

    1998-01-01

    Recently, a joint Brazil-France-U.S. program, known as PIRATA (Pilot Research moored Array in the Tropical Atlantic), was proposed to begin the deployment of moored measurement platforms in the tropical Atlantic in order to enhance the existing observational data base and subsequent understanding of the processes by which the ocean and atmosphere couple in key regions of the tropical Atlantic Ocean. Empirical studies have suggested that there are strong relationships between tropical Atlantic upper ocean variability, SST, ocean-atmosphere coupling and regional climate variability. During the early 1980's a coordinated set of surface wind, subsurface thermal structure, and subsurface current observations were obtained as part of the U.S.-France SEQUAL- FOCAL process experiment designed to observe the seasonal response of the tropical Atlantic Ocean to surface forcing. Since that time, however, the observational data base for the tropical Atlantic Ocean has disintegrated to a few shiptracks measuring ocean temperatures and a small collection of tide gauge stations measuring sea level. A more comprehensive set of observations, modeling and empirical studies is now in order to make progress on understanding the regional climate variability. The proposed PIRATA program will use mooring platforms similar to the tropical Pacific Ocean TAO array to measure surface fluxes of momentum and heat and the corresponding changes in the upper ocean thermal structure. It is anticipated that the oceanic data from this monitoring array will also be used in a predictive mode for initialization studies of regional coupled climate models. Of particular interest are zonal and meridional modes of ocean-atmosphere variability within the tropical Atlantic basin that have significant impacts on the regional climate of the bordering continents.

  1. Theoretical Considerations for Understanding Technological Pedagogical Content Knowledge (TPACK)

    ERIC Educational Resources Information Center

    Graham, Charles R.

    2011-01-01

    The technological pedagogical content knowledge (TPACK) framework is increasing in use by educational technology researchers around the world who are interested in issues related to technology integration. Much that is good can be found in the TPACK framework; however considerable theoretical work needs to be done if TPACK research is to cohere…

  2. A Theoretical Framework towards Understanding of Emotional and Behavioural Difficulties

    ERIC Educational Resources Information Center

    Poulou, Maria S.

    2014-01-01

    Children's emotional and behavioural difficulties are the result of multiple individual, social and contextual factors working in concert. The current paper proposes a theoretical framework to interpret students' emotional and behavioural difficulties in schools, by taking into consideration teacher-student relationships, students'…

  3. Recent advances in understanding and managing urolithiasis

    PubMed Central

    Strohmaier, Walter L.

    2016-01-01

    During the last few years, there has been relevant progress in both understanding and managing urolithiasis. Our knowledge of stone formation has changed; although the importance of urine biochemistry was questioned by several investigators years ago, the decisive role of cellular processes (induced by oxidative stress) and the renal papilla has only recently been generally accepted as the most important step in stone formation. For calcium oxalate urolithiasis, the formation of papillary calcifications plays a key role and is of prognostic relevance. Further research has to concentrate on these aspects of preventing urolithiasis. Stone prevention (metaphylaxis) is a major issue when considering the burden it places on healthcare systems. An effective metaphylaxis could lower the cost of stone therapy significantly. For uric acid urolithiasis, so far there is only preliminary information available showing that papillary plaques are not as important as they are in calcium oxalate urolithiasis. Concerning stone management, endourology has improved stone therapy significantly during the last few years. Morbidity decreased and success (stone-free) rates increased. Therefore, the indications for extracorporeal shockwave lithotripsy (ESWL) narrowed. ESWL, however, still has its place in stone therapy. There is not one single treatment modality that is equally effective for all situations. It is important to observe the differential indications for different stones depending on size, localization, and composition. PMID:27853528

  4. Recent advances in understanding hepatic drug transport

    PubMed Central

    Stieger, Bruno; Hagenbuch, Bruno

    2016-01-01

    Cells need to strictly control their internal milieu, a function which is performed by the plasma membrane. Selective passage of molecules across the plasma membrane is controlled by transport proteins. As the liver is the central organ for drug metabolism, hepatocytes are equipped with numerous drug transporters expressed at the plasma membrane. Drug disposition includes absorption, distribution, metabolism, and elimination of a drug and hence multiple passages of drugs and their metabolites across membranes. Consequently, understanding the exact mechanisms of drug transporters is essential both in drug development and in drug therapy. While many drug transporters are expressed in hepatocytes, and some of them are well characterized, several transporters have only recently been identified as new drug transporters. Novel powerful tools to deorphanize (drug) transporters are being applied and show promising results. Although a large set of tools are available for studying transport in vitro and in isolated cells, tools for studying transport in living organisms, including humans, are evolving now and rely predominantly on imaging techniques, e.g. positron emission tomography. Imaging is an area which, certainly in the near future, will provide important insights into "transporters at work" in vivo. PMID:27781095

  5. Understanding identity integration: Theoretical, methodological, and applied issues.

    PubMed

    Syed, Moin; McLean, Kate C

    2016-02-01

    Identity integration is one of the foundational theoretical concepts in Erikson's (1968) theory of lifespan development. However, the topic is understudied relative to its theoretical and practical importance. The extant research is limited in quantity and scope, and there is considerable heterogeneity in how identity integration is conceptualized and measured. Accordingly, the purpose of this paper is to 1) provide a conceptual discussion of different forms of identity integration 2) highlight the different methodological approaches represented in the literature, and 3) detail the implications of integration for psychological functioning. In particular, we provide a conceptual and methodological discussion of four forms of integration: two that are widely recognized, contextual integration and temporal integration, and two that have received less attention, ego integration and person-society integration. We see this paper as filling a need in the literature for those interested in how complex identity processes are related to psychological functioning.

  6. A theoretical foundation for understanding clergy-perpetrated sexual abuse.

    PubMed

    Fogler, Jason M; Shipherd, Jillian C; Rowe, Erin; Jensen, Jennifer; Clarke, Stephanie

    2008-01-01

    Incorporating elements from broadband theories of psychological adaptation to extreme adversity, including Summit's (1983) Child Sexual Abuse Accommodation Syndrome, Finkelhor and Browne's (1986) Traumagenic Dynamics Model of sexual abuse, and Pyszczynski and colleagues' (1997) Terror Management Theory, this paper proposes a unified theoretical model of clergy-perpetrated sexual abuse for future research. The model conceptualizes clergy-perpetrated sexual abuse as the convergence of interactive processes between the clergy-perpetrator, the parishioner-survivor, and the religious community.

  7. Understanding New Media Literacy: An Explorative Theoretical Framework

    ERIC Educational Resources Information Center

    Lin, Tzu-Bin; Li, Jen-Yi; Deng, Feng; Lee, Ling

    2013-01-01

    With the advent of new media technologies, the role of media in a society has been changed that leads researchers to re-construct the meaning of literacy from classic literacy to new media literacy. There have been continuing efforts to understand new media and promote the importance of becoming new media literate among researchers, educators,…

  8. Understanding International Partnerships: A Theoretical and Practical Approach

    ERIC Educational Resources Information Center

    Taylor, John

    2016-01-01

    Internationalisation is now a key strategic priority for many universities. As part of this process, universities are increasingly looking to build a number of key strategic partnerships with a small number of like-minded institutions. This paper, based on a detailed study of three such partnerships, seeks to understand and theorise the process by…

  9. Understanding International Partnerships: A Theoretical and Practical Approach

    ERIC Educational Resources Information Center

    Taylor, John

    2016-01-01

    Internationalisation is now a key strategic priority for many universities. As part of this process, universities are increasingly looking to build a number of key strategic partnerships with a small number of like-minded institutions. This paper, based on a detailed study of three such partnerships, seeks to understand and theorise the process by…

  10. Understanding New Media Literacy: An Explorative Theoretical Framework

    ERIC Educational Resources Information Center

    Lin, Tzu-Bin; Li, Jen-Yi; Deng, Feng; Lee, Ling

    2013-01-01

    With the advent of new media technologies, the role of media in a society has been changed that leads researchers to re-construct the meaning of literacy from classic literacy to new media literacy. There have been continuing efforts to understand new media and promote the importance of becoming new media literate among researchers, educators,…

  11. Advanced Science Students' Understandings on Nature of Science in Finland

    ERIC Educational Resources Information Center

    Sormunen, Kari; Köksal, Mustafa Serdar

    2014-01-01

    Majority of NOS studies comprise of determination or assessment studies conducted with ordinary students. In order to gain further understanding on variation in NOS understandings among the students, there should be different research attempts focusing on unconventional students such as academically advanced students. The purpose of this study is…

  12. Advancing the understanding of autism disease mechanisms through genetics

    PubMed Central

    de la Torre-Ubieta, Luis; Won, Hyejung; Stein, Jason L; Geschwind, Daniel H

    2016-01-01

    Progress in understanding the genetic etiology of autism spectrum disorders (ASD) has fueled remarkable advances in our understanding of its potential neurobiological mechanisms. Yet, at the same time, these findings highlight extraordinary causal diversity and complexity at many levels ranging from molecules to circuits and emphasize the gaps in our current knowledge. Here we review current understanding of the genetic architecture of ASD and integrate genetic evidence, neuropathology and studies in model systems with how they inform mechanistic models of ASD pathophysiology. Despite the challenges, these advances provide a solid foundation for the development of rational, targeted molecular therapies. PMID:27050589

  13. Understanding the conductance switching of permethyloligosilanes: A theoretical approach

    SciTech Connect

    Pramanik, Anup; Sarkar, Pranab

    2015-09-21

    On the basis of ab initio density functional theory coupled with non-equilibrium Green’s function technique, we have presented a molecular level understanding on the stereoelectronic switching of conducting properties of oligosilane molecules. Su et al. [Nat. Chem. 7, 215–220 (2015)] demonstrated that these types of oligosilane molecules exhibit three stereoconformers which show two distinct conducting profiles. On the basis of break-junction technique, the authors show that manipulating a specific dihedral angle and thereby controlling the length of the molecular contact, it is possible to switch the conducting states minutely. However, their discussions scarce the proper energy level alignment upon which the molecule-lead tunneling amplitude depends. On the basis of electronic structure and non-equilibrium electron transport calculations, we interpret such switching behavior and thus quantify the switching parameter demonstrating how the metal-molecule contact geometry along with the electronic energy level alignment is responsible for such kind of junction process. We also provide the variation of switching parameter and the type of majority carrier with the conjugation length of the oligosilanes.

  14. Advances in multiscale theoretical analysis and imaging aspects of turbulence

    NASA Astrophysics Data System (ADS)

    Shockro, Jennifer

    turbulent jet scalar interface. Understanding aspects of turbulent interfacial behavior provides information about the manner in which directed lasers propagate through atmospheric turbulence, such as cloud formations and fog, and is necessary to the development of new technologies such as free-space laser communications. The mathematical basis of the M(3) method is described and is shown to be a theoretical approach that is useful for analysis of multiscale and multiorientation properties of level crossings of fluctuating fields, such as those present in experimental images of concentration fields and scalar interfaces in turbulent jets. The approach is based on considering the analytical relation between the shortest-distance probability density function and the generalized fractal dimension as a function of scale, and the corresponding orientation probability density function. The shortest distance refers to the distance between any randomly located point within a reference boundary to the nearest to part of the object of interest. For example, for a turbulent interface, the shortest distance is the distance between a random point and the nearest part of the interface. The orientation corresponding to the shortest-distance scale is the direction of the vector from the random point to the nearest part of the object, as in anisotropic studies. The method is used to analyze images obtained using laser Mie scattering of a fog seeded jet of air in an experimental flow facility. Care was taken in experiments to create a fog volume fraction that is both representative of certain natural fog occurrences and that ensures negligible effects on the turbulent geometric structures present. The Mie imaging and fog seeding of air are employed to quantitatively visualize the turbulent jet concentration field as a cross section of the jet and the images of the concentration field are used to extract scalar interfaces. The shortest-distance M(3) method is applied to theimaged scalar

  15. Beyond Homophily: A Decade of Advances in Understanding Peer Influence Processes

    PubMed Central

    Brechwald, Whitney A.; Prinstein, Mitchell J.

    2013-01-01

    This article reviews empirical and theoretical contributions to a multidisciplinary understanding of peer influence processes in adolescence over the past decade. Five themes of peer influence research from this decade were identified, including a broadening of the range of behaviors for which peer influence occurs, distinguishing the sources of influence, probing the conditions under which influence is amplified/attenuated (moderators), testing theoretically based models of peer influence processes (mechanisms), and preliminary exploration of behavioral neuroscience perspectives on peer influence. This review highlights advances in each of these areas, underscores gaps in current knowledge of peer influence processes, and outlines important challenges for future research. PMID:23730122

  16. Advances in heterogeneous ice nucleation research: Theoretical modeling and measurements

    NASA Astrophysics Data System (ADS)

    Beydoun, Hassan

    In the atmosphere, cloud droplets can remain in a supercooled liquid phase at temperatures as low as -40 °C. Above this temperature, cloud droplets freeze via heterogeneous ice nucleation whereby a rare and poorly understood subset of atmospheric particles catalyze the ice phase transition. As the phase state of clouds is critical in determining their radiative properties and lifetime, deficiencies in our understanding of heterogeneous ice nucleation poses a large uncertainty on our efforts to predict human induced global climate change. Experimental challenges in properly simulating particle-induced freezing processes under atmospherically relevant conditions have largely contributed to the absence of a well-established model and parameterizations that accurately predict heterogeneous ice nucleation. Conversely, the sparsity of reliable measurement techniques available struggle to be interpreted by a single consistent theoretical or empirical framework, which results in layers of uncertainty when attempting to extrapolate useful information regarding ice nucleation for use in atmospheric cloud models. In this dissertation a new framework for describing heterogeneous ice nucleation is developed. Starting from classical nucleation theory, the surface of an ice nucleating particle is treated as a continuum of heterogeneous ice nucleating activity and a particle specific distribution of this activity g is derived. It is hypothesized that an individual particle species exhibits a critical surface area. Above this critical area the ice nucleating activity of a particle species can be described by one g distribution, g, while below it g expresses itself expresses externally resulting in particle to particle variability in ice nucleating activity. The framework is supported by cold plate droplet freezing measurements for dust and biological particles in which the total surface area of particle material available is varied. Freezing spectra above a certain surface area

  17. How International Research on Parenting Advances Understanding of Child Development.

    PubMed

    Lansford, Jennifer E; Bornstein, Marc H; Deater-Deckard, Kirby; Dodge, Kenneth A; Al-Hassan, Suha M; Bacchini, Dario; Bombi, Anna Silvia; Chang, Lei; Chen, Bin-Bin; Di Giunta, Laura; Malone, Patrick S; Oburu, Paul; Pastorelli, Concetta; Skinner, Ann T; Sorbring, Emma; Steinberg, Laurence; Tapanya, Sombat; Alampay, Liane Peña; Tirado, Liliana Maria Uribe; Zelli, Arnaldo

    2016-09-01

    International research on parenting and child development can advance our understanding of similarities and differences in how parenting is related to children's development across countries. Challenges to conducting international research include operationalizing culture, disentangling effects within and between countries, and balancing emic and etic perspectives. Benefits of international research include testing whether findings regarding parenting and child development replicate across diverse samples, incorporating cultural and contextual diversity to foster more inclusive and representative research samples and investigators than has typically occurred, and understanding how children develop in proximal parenting and family and distal international contexts.

  18. How International Research on Parenting Advances Understanding of Child Development

    PubMed Central

    Lansford, Jennifer E.; Bornstein, Marc H.; Deater-Deckard, Kirby; Dodge, Kenneth A.; Al-Hassan, Suha M.; Bacchini, Dario; Bombi, Anna Silvia; Chang, Lei; Chen, Bin-Bin; Di Giunta, Laura; Malone, Patrick S.; Oburu, Paul; Pastorelli, Concetta; Skinner, Ann T.; Sorbring, Emma; Steinberg, Laurence; Tapanya, Sombat; Alampay, Liane Peña; Tirado, Liliana Maria Uribe; Zelli, Arnaldo

    2016-01-01

    International research on parenting and child development can advance our understanding of similarities and differences in how parenting is related to children's development across countries. Challenges to conducting international research include operationalizing culture, disentangling effects within and between countries, and balancing emic and etic perspectives. Benefits of international research include testing whether findings regarding parenting and child development replicate across diverse samples, incorporating cultural and contextual diversity to foster more inclusive and representative research samples and investigators than has typically occurred, and understanding how children develop in proximal parenting and family and distal international contexts. PMID:27725843

  19. Advances and challenges in understanding histone demethylase biology.

    PubMed

    Nowak, Radoslaw P; Tumber, Anthony; Johansson, Catrine; Che, Ka Hing; Brennan, Paul; Owen, Dafydd; Oppermann, Udo

    2016-08-01

    Within the last decade we have witnessed significant progress in the field of chromatin methylation, ranging from the discovery that chromatin methylation is reversible, to the identification of two classes of oxidative chromatin demethylases. Multiple genetic and cellular studies emphasize the role of members of the amine oxidase and 2-oxoglutarate oxygenase enzyme families involved in methyl-lysine in physiology and disease. Advances in understanding of the underlying biochemistry have resulted in development of first series of clinical inhibitors and tool compounds which continue to resolve and help understand the complex relationships between chromatin modification, control of gene expression and metabolic states. Copyright © 2016. Published by Elsevier Ltd.

  20. Theoretical Investigations of Plasma-Based Accelerators and Other Advanced Accelerator Concepts

    SciTech Connect

    Shuets, G.

    2004-05-21

    Theoretical investigations of plasma-based accelerators and other advanced accelerator concepts. The focus of the work was on the development of plasma based and structure based accelerating concepts, including laser-plasma, plasma channel, and microwave driven plasma accelerators.

  1. University Students' Understanding of the Concepts Empirical, Theoretical, Qualitative and Quantitative Research

    ERIC Educational Resources Information Center

    Murtonen, Mari

    2015-01-01

    University research education in many disciplines is frequently confronted by problems with students' weak level of understanding of research concepts. A mind map technique was used to investigate how students understand central methodological concepts of empirical, theoretical, qualitative and quantitative. The main hypothesis was that some…

  2. University Students' Understanding of the Concepts Empirical, Theoretical, Qualitative and Quantitative Research

    ERIC Educational Resources Information Center

    Murtonen, Mari

    2015-01-01

    University research education in many disciplines is frequently confronted by problems with students' weak level of understanding of research concepts. A mind map technique was used to investigate how students understand central methodological concepts of empirical, theoretical, qualitative and quantitative. The main hypothesis was that some…

  3. A general theoretical framework for understanding essential dynamics of Madden-Julian oscillation

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Chen, Guosen

    2016-11-01

    Motivated by observed structure of Madden-Julian oscillation (MJO), a general theoretical model framework is advanced for understanding fundamental aspects of MJO dynamics. The model extends the Matsuno-Gill theory by incorporating (a) moisture feedback to precipitation, (b) a trio-interaction among equatorial waves, boundary layer (BL) dynamics, and precipitation, and (c) a simplified Betts-Miller (B-M) cumulus parameterization. The general model with B-M scheme yields a frictionally coupled dynamic moisture mode, which produces an equatorial planetary-scale, unstable system moving eastward slowly with coupled Kelvin-Rossby wave structure and BL moisture convergence leading major convection. The moisture feedback in B-M scheme reinforces the coupling between precipitation heating and Rossby waves and enhances the Rossby wave component in the MJO mode, thereby slowing down eastward propagation and resulting in a more realistic horizontal structure. It is, however, the BL frictional convergence feedback that couples equatorial Kelvin and Rossby waves with convective heating and selects a preferred eastward propagation. The eastward propagation speed in the model is inversely related to the relative intensity of the equatorial "Rossby" westerly versus "Kelvin" easterly associated with the MJO. The cumulus parameterization scheme may affect propagation speed through changing MJO horizontal structure. The SST or basic-state moist static energy has a fundamental control on MJO propagation speed and intensification/decay. Model sensitivity to BL and cumulus scheme parameters and ramifications of the model results to general circulation modeling are discussed.

  4. On the Radau pseudospectral method: theoretical and implementation advances

    NASA Astrophysics Data System (ADS)

    Sagliano, Marco; Theil, Stephan; Bergsma, Michiel; D'Onofrio, Vincenzo; Whittle, Lisa; Viavattene, Giulia

    2017-06-01

    In the last decades the theoretical development of more and more refined direct methods, together with a new generation of CPUs, led to a significant improvement of numerical approaches for solving optimal-control problems. One of the most promising class of methods is based on pseudospectral optimal control. These methods do not only provide an efficient algorithm to solve optimal-control problems, but also define a theoretical framework for linking the discrete numerical solution to the analytical one in virtue of the covector mapping theorem. However, several aspects in their implementation can be refined. In this framework SPARTAN, the first European tool based on flipped-Radau pseudospectral method, has been developed. This paper illustrates the aspects implemented for SPARTAN, which can potentially be valid for any other transcription. The novelties included in this work consist specifically of a new hybridization of the Jacobian matrix computation made of four distinct parts. These contributions include a new analytical formulation for expressing Lagrange cost function for open final-time problems, and the use of dual-number theory for ensuring exact differentiation. Moreover, a self-scaling strategy for primal and dual variables, which combines the projected-Jacobian rows normalization and the covector mapping, is described. Three concrete examples show the validity of the novelties introduced, and the quality of the results obtained with the proposed methods.

  5. On the Radau pseudospectral method: theoretical and implementation advances

    NASA Astrophysics Data System (ADS)

    Sagliano, Marco; Theil, Stephan; Bergsma, Michiel; D'Onofrio, Vincenzo; Whittle, Lisa; Viavattene, Giulia

    2017-09-01

    In the last decades the theoretical development of more and more refined direct methods, together with a new generation of CPUs, led to a significant improvement of numerical approaches for solving optimal-control problems. One of the most promising class of methods is based on pseudospectral optimal control. These methods do not only provide an efficient algorithm to solve optimal-control problems, but also define a theoretical framework for linking the discrete numerical solution to the analytical one in virtue of the covector mapping theorem. However, several aspects in their implementation can be refined. In this framework SPARTAN, the first European tool based on flipped-Radau pseudospectral method, has been developed. This paper illustrates the aspects implemented for SPARTAN, which can potentially be valid for any other transcription. The novelties included in this work consist specifically of a new hybridization of the Jacobian matrix computation made of four distinct parts. These contributions include a new analytical formulation for expressing Lagrange cost function for open final-time problems, and the use of dual-number theory for ensuring exact differentiation. Moreover, a self-scaling strategy for primal and dual variables, which combines the projected-Jacobian rows normalization and the covector mapping, is described. Three concrete examples show the validity of the novelties introduced, and the quality of the results obtained with the proposed methods.

  6. Nursing staff's understanding expressions of people with advanced dementia disease.

    PubMed

    Eggers, Thomas; Ekman, Sirkka-Liisa; Norberg, Astrid

    2013-01-01

    People with advanced dementia disease (ADD) are known to have communication difficulties and thus it presents a challenge in understanding the expressions of these people. Because successful communication presupposes cooperation at least between 2 individuals, both individual's actions must be acknowledged. The aim of this study is to describe nursing staff's ways of understanding the expressions of people with ADD when communicating with them. Interviews from 8 nursing staff were analyzed using qualitative content analysis. Two themes were constructed: "Being in communication" and "Doing communication." Being in communication means that nursing staff perceive people with ADD as being capable of communication. Doing communication means that nursing staff attempt different individualized strategies to understand what people with ADD communicate. Good care of people with ADD presupposes nursing staff that are willing and able to relate to other people and to maintain good care for people with ADD continuous education and supervision are needed.

  7. Advances in understanding basic mechanisms of epilepsy and seizures.

    PubMed

    Jefferys, John G R

    2010-12-01

    Sixty years ago the clinical neurophysiology of epilepsy had progressed to the stage that it posed questions that could be addressed by major advances in cellular electrophysiology made around the that time. However, it took about 25-30 years to build up serious momentum in understanding the mechanisms of epileptic discharges. Over the past 2-3 decades developments in pharmacology and molecular biology have substantially increased the depth and complexity of our insights into the nervous system in general and the epileptic brain in particular. One of the biggest advances in our understanding of the brain is in its plasticity in the adult - that is its ability to modify its structure and function. The current state of play is that for most chronic epileptic foci it is possible to identify multiple differences from normal brain tissue in both the structure and function of neurons, neuronal networks and glia. This review will chart some of this progress to give an idea of the pace of advances over the decades.

  8. Experimental and theoretical advances in prosody: A review

    PubMed Central

    Wagner, Michael; Watson, Duane G.

    2011-01-01

    Research on prosody has recently become an important focus in various disciplines, including Linguistics, Psychology, and Computer Science. This article reviews recent research advances on two key issues: prosodic phrasing and prosodic prominence. Both aspects of prosody are influenced by linguistic factors such as syntactic constituent structure, semantic relations, phonological rhythm, pragmatic considerations, and also by processing factors such as the length, complexity or predictability of linguistic material. Our review summarizes recent insights into the production and perception of these two components of prosody and their grammatical underpinnings. While this review only covers a subset of a broader set of research topics on prosody in cognitive science, they are representative of a tendency in the field toward a more interdisciplinary approach. PMID:22096264

  9. Recent advances in understanding Epstein-Barr virus.

    PubMed

    Stanfield, Brent A; Luftig, Micah A

    2017-01-01

    Epstein-Barr virus (EBV) is a common human herpes virus known to infect the majority of the world population. Infection with EBV is often asymptomatic but can manifest in a range of pathologies from infectious mononucleosis to severe cancers of epithelial and lymphocytic origin. Indeed, in the past decade, EBV has been linked to nearly 10% of all gastric cancers. Furthermore, recent advances in high-throughput next-generation sequencing and the development of humanized mice, which effectively model EBV pathogenesis, have led to a wealth of knowledge pertaining to strain variation and host-pathogen interaction. This review highlights some recent advances in our understanding of EBV biology, focusing on new findings on the early events of infection, the role EBV plays in gastric cancer, new strain variation, and humanized mouse models of EBV infection.

  10. Recent advances in understanding Epstein-Barr virus

    PubMed Central

    Stanfield, Brent A.; Luftig, Micah A.

    2017-01-01

    Epstein-Barr virus (EBV) is a common human herpes virus known to infect the majority of the world population. Infection with EBV is often asymptomatic but can manifest in a range of pathologies from infectious mononucleosis to severe cancers of epithelial and lymphocytic origin. Indeed, in the past decade, EBV has been linked to nearly 10% of all gastric cancers. Furthermore, recent advances in high-throughput next-generation sequencing and the development of humanized mice, which effectively model EBV pathogenesis, have led to a wealth of knowledge pertaining to strain variation and host-pathogen interaction. This review highlights some recent advances in our understanding of EBV biology, focusing on new findings on the early events of infection, the role EBV plays in gastric cancer, new strain variation, and humanized mouse models of EBV infection. PMID:28408983

  11. Understanding the computing system domain of advanced computing with microcomputers

    SciTech Connect

    Hake, K.A.

    1990-01-01

    Accepting the challenge by the Executive Office of the President, Office of Science and Technology Policy for research to keep pace with technology, the author surveys the knowledge domain of advanced microcomputers. The paper provides a general background for social scientists in technology traditionally relegated to computer science and engineering. The concept of systems integration serves as a framework of understanding for the various elements of the knowledge domain of advanced microcomputing. The systems integration framework is viewed as a series of interrelated building blocks composed of the domain elements. These elements are: the processor platform, operating system, display technology, mass storage, application software, and human-computer interface. References come from recent articles in popular magazines and journals to help emphasize the easy access of this information, its appropriate technical level for the social scientist, and its transient currency. 78 refs., 3 figs.

  12. A view on advances in spheromak understanding and parameters

    SciTech Connect

    Fernandez, J.C.; Chrien, R.E.; Wysocki, F.J.; Mayo, R.M.; Henins, I.

    1990-01-01

    A spheromak is a toroidally-shaped magnetized plasma configuration in which no material (such as coils or vacuum vessels) links the torus, so that the topology of the spheromak boundary is spherical. In the period since the properties of a nearly force-free ({Delta} {times} {rvec B} {approx} {lambda}{rvec B}) spheromak configuration were described using single-fluid MHD theory, and since the first spheromak was formed at the Univ. of Maryland, remarkable theoretical and experimental advances have been made. This paper highlights some of that work. Some of the latest results from the CTX group at Los Alamos are also presented. These include the observation of suprathermal electrons in CTX, evidence by X-ray bursts with photon energies above 1 MeV.

  13. Structural Tailoring of Advanced Turboprops (STAT). Theoretical manual

    NASA Technical Reports Server (NTRS)

    Brown, K. W.

    1992-01-01

    This manual describes the theories in the Structural Tailoring of Advanced Turboprops (STAT) computer program, which was developed to perform numerical optimizations on highly swept propfan blades. The optimization procedure seeks to minimize an objective function, defined as either direct operating cost or aeroelastic differences between a blade and its scaled model, by tuning internal and external geometry variables that must satisfy realistic blade design constraints. The STAT analyses include an aerodynamic efficiency evaluation, a finite element stress and vibration analysis, an acoustic analysis, a flutter analysis, and a once-per-revolution (1-p) forced response life prediction capability. The STAT constraints include blade stresses, blade resonances, flutter, tip displacements, and a 1-P forced response life fraction. The STAT variables include all blade internal and external geometry parameters needed to define a composite material blade. The STAT objective function is dependent upon a blade baseline definition which the user supplies to describe a current blade design for cost optimization or for the tailoring of an aeroelastic scale model.

  14. Recent advances in understanding the cellular roles of GSK-3

    PubMed Central

    Cormier, Kevin W.; Woodgett, James R.

    2017-01-01

    Glycogen synthase kinase-3 (GSK-3) is a ubiquitously expressed protein kinase that sits at the nexus of multiple signaling pathways. Its deep integration into cellular control circuits is consummate to its implication in diseases ranging from mood disorders to diabetes to neurodegenerative diseases and cancers. The selectivity and insulation of such a promiscuous kinase from unwanted crosstalk between pathways, while orchestrating a multifaceted response to cellular stimuli, offer key insights into more general mechanisms of cell regulation. Here, we review recent advances that have contributed to the understanding of GSK-3 and its role in driving appreciation of intracellular signal coordination. PMID:28299185

  15. Recent advances in understanding nuclear size and shape.

    PubMed

    Mukherjee, Richik N; Chen, Pan; Levy, Daniel L

    2016-04-25

    Size and shape are important aspects of nuclear structure. While normal cells maintain nuclear size within a defined range, altered nuclear size and shape are associated with a variety of diseases. It is unknown if altered nuclear morphology contributes to pathology, and answering this question requires a better understanding of the mechanisms that control nuclear size and shape. In this review, we discuss recent advances in our understanding of the mechanisms that regulate nuclear morphology, focusing on nucleocytoplasmic transport, nuclear lamins, the endoplasmic reticulum, the cell cycle, and potential links between nuclear size and size regulation of other organelles. We then discuss the functional significance of nuclear morphology in the context of early embryonic development. Looking toward the future, we review new experimental approaches that promise to provide new insights into mechanisms of nuclear size control, in particular microfluidic-based technologies, and discuss how altered nuclear morphology might impact chromatin organization and physiology of diseased cells.

  16. Recent advances in understanding nuclear size and shape

    PubMed Central

    Mukherjee, Richik N.; Chen, Pan; Levy, Daniel L.

    2016-01-01

    ABSTRACT Size and shape are important aspects of nuclear structure. While normal cells maintain nuclear size within a defined range, altered nuclear size and shape are associated with a variety of diseases. It is unknown if altered nuclear morphology contributes to pathology, and answering this question requires a better understanding of the mechanisms that control nuclear size and shape. In this review, we discuss recent advances in our understanding of the mechanisms that regulate nuclear morphology, focusing on nucleocytoplasmic transport, nuclear lamins, the endoplasmic reticulum, the cell cycle, and potential links between nuclear size and size regulation of other organelles. We then discuss the functional significance of nuclear morphology in the context of early embryonic development. Looking toward the future, we review new experimental approaches that promise to provide new insights into mechanisms of nuclear size control, in particular microfluidic-based technologies, and discuss how altered nuclear morphology might impact chromatin organization and physiology of diseased cells. PMID:26963026

  17. Assessing Students' Understandings of Biological Models and their Use in Science to Evaluate a Theoretical Framework

    NASA Astrophysics Data System (ADS)

    Grünkorn, Juliane; Belzen, Annette Upmeier zu; Krüger, Dirk

    2014-07-01

    Research in the field of students' understandings of models and their use in science describes different frameworks concerning these understandings. Currently, there is no conjoint framework that combines these structures and so far, no investigation has focused on whether it reflects students' understandings sufficiently (empirical evaluation). Therefore, the purpose of this article is to present the results of an empirical evaluation of a conjoint theoretical framework. The theoretical framework integrates relevant research findings and comprises five aspects which are subdivided into three levels each: nature of models, multiple models, purpose of models, testing, and changing models. The study was conducted with a sample of 1,177 seventh to tenth graders (aged 11-19 years) using open-ended items. The data were analysed by identifying students' understandings of models (nature of models and multiple models) and their use in science (purpose of models, testing, and changing models), and comparing as well as assigning them to the content of the theoretical framework. A comprehensive category system of students' understandings was thus developed. Regarding the empirical evaluation, the students' understandings of the nature and the purpose of models were sufficiently described by the theoretical framework. Concerning the understandings of multiple, testing, and changing models, additional initial understandings (only one model possible, no testing of models, and no change of models) need to be considered. This conjoint and now empirically tested framework for students' understandings can provide a common basis for future science education research. Furthermore, evidence-based indications can be provided for teachers and their instructional practice.

  18. Utilizing the Theoretical Framework of Collective Identity to Understand Processes in Youth Programs

    ERIC Educational Resources Information Center

    Futch, Valerie A.

    2016-01-01

    This article explores collective identity as a useful theoretical framework for understanding social and developmental processes that occur in youth programs. Through narrative analysis of past participant interviews (n = 21) from an after-school theater program, known as "The SOURCE", it was found that participants very clearly describe…

  19. Utilizing the Theoretical Framework of Collective Identity to Understand Processes in Youth Programs

    ERIC Educational Resources Information Center

    Futch, Valerie A.

    2016-01-01

    This article explores collective identity as a useful theoretical framework for understanding social and developmental processes that occur in youth programs. Through narrative analysis of past participant interviews (n = 21) from an after-school theater program, known as "The SOURCE", it was found that participants very clearly describe…

  20. A Theoretical Analysis of Social Interactions in Computer-based Learning Environments: Evidence for Reciprocal Understandings.

    ERIC Educational Resources Information Center

    Jarvela, Sanna; Bonk, Curtis Jay; Lehtinen, Erno; Lehti, Sirpa

    1999-01-01

    Presents a theoretical and empirical analysis of social interactions in computer-based learning environments. Explores technology use to support reciprocal understanding between teachers and students based on three technology-based learning environments in Finland and the United States, and discusses situated learning, cognitive apprenticeships,…

  1. Compassion Fatigue as a Theoretical Framework to Help Understand Burnout among Special Education Teachers

    ERIC Educational Resources Information Center

    Hoffman, Shari; Palladino, John M.; Barnett, Jeffery

    2007-01-01

    Compassion fatigue is a theoretical framework researchers have applied to helping professions other than teaching. The purpose of this report is to propose the use of this theory to better understand the prevalent rates of special education teachers' exit from the profession often labeled as burnout. A qualitative study with six middle school…

  2. Developing a Theoretical Framework for Examining Student Understanding of Fractional Concepts: An Historical Accounting

    ERIC Educational Resources Information Center

    Cooper, Susan M.; Wilkerson, Trena L.; Montgomery, Mark; Mechell, Sara; Arterbury, Kristin; Moore, Sherrie

    2012-01-01

    In 2007, a group of mathematics educators and researchers met to examine rational numbers and why children have such an issue with them. An extensive review of the literature on fractional understanding was conducted. The ideas in that literature were then consolidated into a theoretical framework for examining fractions. Once that theoretical…

  3. Advances in understanding the mechanism of zebrafish heart regeneration.

    PubMed

    Kikuchi, Kazu

    2014-11-01

    The adult mammalian heart was once believed to be a post-mitotic organ without any capacity for regeneration, but recent findings have challenged this dogma. A modified view assigns the mammalian heart a measurable capacity for regeneration throughout its lifetime, with the implication that endogenous regenerative capacity can be therapeutically stimulated in the injury setting. Although extremely limited in adult mammals, the natural capacity for organ regeneration is a conserved trait in certain vertebrates. Urodele amphibians and teleosts are well-known examples of such animals that can efficiently regenerate various organs including the heart as adults. By understanding how these animals regenerate a damaged heart, one might obtain valuable insights into how regeneration can be augmented in injured human hearts. Among the regenerative vertebrate models, the teleost zebrafish, Danio rerio, is arguably the best characterized with respect to cardiac regenerative responses. Knowledge is still limited, but a decade of research in this model has led to results that may help to understand how cardiac regeneration is naturally stimulated and maintained. This review surveys recent advances in the field and discusses current understanding of the endogenous mechanisms of cardiac regeneration in zebrafish. Copyright © 2014. Published by Elsevier B.V.

  4. Recent advances in the understanding of severe cutaneous adverse reactions.

    PubMed

    Adler, N R; Aung, A K; Ergen, E N; Trubiano, J; Goh, M S Y; Phillips, E J

    2017-03-03

    Severe cutaneous adverse reactions (SCARs) encompass a heterogeneous group of delayed hypersensitivity reactions, which are most frequently caused by drugs. Our understanding of several aspects of SCAR syndromes has evolved considerably over the last decade. This review explores evolving knowledge of the immunopathogenic mechanisms, pharmacogenomic associations, in vivo and ex vivo diagnostics for causality assessment, and medication cross-reactivity data related to SCAR syndromes. Given the rarity and severity of these diseases, multidisciplinary collaboration through large international, national and/or multicentre networks to collect prospective data on patients with SCAR syndromes should be prioritized. This will further enhance a systematized framework for translating epidemiological, clinical and immunopathogenetic advances into preventive efforts and improved outcomes for patients. © 2017 British Association of Dermatologists.

  5. Advancing Understanding of Earthquakes by Drilling an Eroding Convergent Margin

    NASA Astrophysics Data System (ADS)

    von Huene, R.; Vannucchi, P.; Ranero, C. R.

    2010-12-01

    A program of IODP with great societal relevance is sampling and instrumenting the seismogenic zone. The zone generates great earthquakes that trigger tsunamis, and submarine slides thereby endangering coastal communities containing over sixty percent of the earth’s population. To asses and mitigate this endangerment it is urgent to advance understanding of fault dynamics that allows more timely anticipation of hazardous seismicity. Seismogenesis on accreting and eroding convergent plate boundaries apparently differ because of dissimilar materials along the interplate fault. As the history of instrumentally recorded earthquakes expands the difference becomes clearer. The more homogeneous clay, silt and sand subducted at accreting margins is associated with great earthquakes (M 9) whereas the fragmented upper plate rock that can dominate subducted material along an eroding margin plate interface is associated with many tsunamigenic earthquakes (Bilek, 2010). Few areas have been identified where the seismogenic zone can be reached with scientific drilling. In IODP accreting margins are studied on the NanTroSeize drill transect off Japan where the ultimate drilling of the seismogenic interface may occur by the end of IODP. The eroding Costa Rica margin will be studied in CRISP where a drill program will begin in 2011. The Costa Rican geophysical site survey will be complete with acquisition and processing of 3D seismic data in 2011 but the entire drilling will not be accomplished in IODP. It is appropriate that the accreting margin study be accomplished soon considering the indications of a pending great earthquake that will affect a country that has devoted enormous resources to IODP. However, understanding the erosional end-member is scientifically as important to an understanding of fault mechanics. Transoceanic tsunamis affect the entire Pacific rim where most subduction zones are eroding margins. The Costa Rican subduction zone is less complex operationally and

  6. Recent advances in understanding Antarctic subglacial lakes and hydrology

    PubMed Central

    Siegert, Martin J.; Ross, Neil; Le Brocq, Anne M.

    2016-01-01

    It is now well documented that over 400 subglacial lakes exist across the bed of the Antarctic Ice Sheet. They comprise a variety of sizes and volumes (from the approx. 250 km long Lake Vostok to bodies of water less than 1 km in length), relate to a number of discrete topographic settings (from those contained within valleys to lakes that reside in broad flat terrain) and exhibit a range of dynamic behaviours (from ‘active’ lakes that periodically outburst some or all of their water to those isolated hydrologically for millions of years). Here we critique recent advances in our understanding of subglacial lakes, in particular since the last inventory in 2012. We show that within 3 years our knowledge of the hydrological processes at the ice-sheet base has advanced considerably. We describe evidence for further ‘active’ subglacial lakes, based on satellite observation of ice-surface changes, and discuss why detection of many ‘active’ lakes is not resolved in traditional radio-echo sounding methods. We go on to review evidence for large-scale subglacial water flow in Antarctica, including the discovery of ancient channels developed by former hydrological processes. We end by predicting areas where future discoveries may be possible, including the detection, measurement and significance of groundwater (i.e. water held beneath the ice-bed interface). PMID:26667914

  7. Advancing our understanding of the human microbiome using QIIME

    PubMed Central

    Navas-Molina, José A.; Peralta-Sánchez, Juan M.; González, Antonio; McMurdie, Paul J.; Vázquez-Baeza, Yoshiki; Xu, Zhenjiang; Ursell, Luke K.; Lauber, Christian; Zhou, Hongwei; Song, Se Jin; Huntley, James; Ackermann, Gail L.; Berg-Lyons, Donna; Holmes, Susan; Caporaso, J. Gregory; Knight, Rob

    2014-01-01

    High-throughput DNA sequencing technologies, coupled with advanced bioinformatics tools, have enabled rapid advances in microbial ecology and our understanding of the human microbiome. QIIME (Quantitative Insights Into Microbial Ecology) is an open-source bioinformatics software package designed for microbial community analysis based on DNA sequence data, which provides a single analysis framework for analysis of raw sequence data through publication quality statistical analyses and interactive visualizations. In this paper, we demonstrate the use of the QIIME pipeline to analyze microbial communities obtained from several sites on the bodies of transgenic and wild-type mice, as assessed using 16S rRNA gene sequences generated on the Illumina MiSeq platform. We present our recommended pipeline for performing microbial community analysis, and provide guidelines for making critical choices in the process. We present examples of some of the types of analyses that are enabled by QIIME, and discuss how other tools, such as phyloseq and R, can be applied to expand upon these analyses. PMID:24060131

  8. Recent advances in understanding Antarctic subglacial lakes and hydrology.

    PubMed

    Siegert, Martin J; Ross, Neil; Le Brocq, Anne M

    2016-01-28

    It is now well documented that over 400 subglacial lakes exist across the bed of the Antarctic Ice Sheet. They comprise a variety of sizes and volumes (from the approx. 250 km long Lake Vostok to bodies of water less than 1 km in length), relate to a number of discrete topographic settings (from those contained within valleys to lakes that reside in broad flat terrain) and exhibit a range of dynamic behaviours (from 'active' lakes that periodically outburst some or all of their water to those isolated hydrologically for millions of years). Here we critique recent advances in our understanding of subglacial lakes, in particular since the last inventory in 2012. We show that within 3 years our knowledge of the hydrological processes at the ice-sheet base has advanced considerably. We describe evidence for further 'active' subglacial lakes, based on satellite observation of ice-surface changes, and discuss why detection of many 'active' lakes is not resolved in traditional radio-echo sounding methods. We go on to review evidence for large-scale subglacial water flow in Antarctica, including the discovery of ancient channels developed by former hydrological processes. We end by predicting areas where future discoveries may be possible, including the detection, measurement and significance of groundwater (i.e. water held beneath the ice-bed interface).

  9. Advancing understanding of executive function impairments and psychopathology: bridging the gap between clinical and cognitive approaches

    PubMed Central

    Snyder, Hannah R.; Miyake, Akira; Hankin, Benjamin L.

    2015-01-01

    Executive function (EF) is essential for successfully navigating nearly all of our daily activities. Of critical importance for clinical psychological science, EF impairments are associated with most forms of psychopathology. However, despite the proliferation of research on EF in clinical populations, with notable exceptions clinical and cognitive approaches to EF have remained largely independent, leading to failures to apply theoretical and methodological advances in one field to the other field and hindering progress. First, we review the current state of knowledge of EF impairments associated with psychopathology and limitations to the previous research in light of recent advances in understanding and measuring EF. Next, we offer concrete suggestions for improving EF assessment. Last, we suggest future directions, including integrating modern models of EF with state of the art, hierarchical models of dimensional psychopathology as well as translational implications of EF-informed research on clinical science. PMID:25859234

  10. Recent experimental advances for understanding bubble-particle attachment in flotation.

    PubMed

    Xing, Yaowen; Gui, Xiahui; Pan, Lei; Pinchasik, Bat-El; Cao, Yijun; Liu, Jiongtian; Kappl, Michael; Butt, Hans-Jürgen

    2017-08-01

    Bubble-particle interaction is of great theoretical and practical importance in flotation. Significant progress has been achieved over the past years and the process of bubble-particle collision is reasonably well understood. This, however, is not the case for bubble-particle attachment leading to three-phase contact line formation due to the difficulty in both theoretical analysis and experimental verification. For attachment, surface forces play a major role. They control the thinning and rupture of the liquid film between the bubble and the particle. The coupling between force, bubble deformation and film drainage is critical to understand the underlying mechanism responsible for bubble-particle attachment. In this review we first discuss the advances in macroscopic experimental methods for characterizing bubble-particle attachment such as induction timer and high speed visualization. Then we focus on advances in measuring the force and drainage of thin liquid films between an air bubble and a solid surface at a nanometer scale. Advances, limits, challenges, and future research opportunities are discussed. By combining atomic force microscopy and reflection interference contrast microscopy, the force, bubble deformation, and liquid film drainage can be measured simultaneously. The simultaneous measurement of the interaction force and the spatiotemporal evolution of the confined liquid film hold great promise to shed new light on flotation. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Recent advances in the understanding and management of delayed puberty.

    PubMed

    Wei, Christina; Crowne, Elizabeth Clare

    2016-05-01

    Delayed puberty, especially in boys, is a common presentation in paediatrics. Recent advances have improved our understanding of the neuroendocrine, genetic and environmental factors controlling pubertal development, and hence inform the pathophysiology of delayed puberty. The discovery of kisspeptin signalling through its receptor identified neuroendocrine mechanisms controlling the gonadotrophin-releasing hormone (GnRH) pulse generator at the onset of puberty. Genetic mechanisms from single gene mutations to single nucleotide polymorphism associated with delayed puberty are being identified. Environmental factors, including nutritional factors and endocrine disruptors, have also been implicated in changes in secular trends and abnormal timing of puberty. Despite these advances, the key clinical question is to distinguish delayed puberty associated with an underlying pathology or hypogonadism from constitutional delay in growth and puberty, which remains challenging as biochemical tests are not always discriminatory. The diagnostic accuracies of newer investigations, including 36-hour luteinising hormone releasing hormone (LHRH) tests, GnRH-agonist tests, antimullerian hormone and inhibin-B, require further evaluation. Sex hormone replacement remains the main available treatment for delayed puberty, the choice of which is largely dictated by clinical practice and availability of the various sex steroid preparations. Spontaneous reversal of hypogonadism has been reported in boys with idiopathic hypogonadotrophic hypogonadism after a period of sex steroid treatment, highlighting the importance of reassessment at the end of pubertal induction. Novel therapies with a more physiological basis such as gonadotrophins or kisspeptin-agonist are being investigated for the management of hypogonadotrophic hypogonadism. Careful clinical assessment and appreciation of the normal physiology remain the key approach to patients with delayed puberty.

  12. Recent advances in understanding and treating nephrotic syndrome

    PubMed Central

    Bierzynska, Agnieszka; Saleem, Moin

    2017-01-01

    Idiopathic nephrotic syndrome (INS) is one of the most common glomerular diseases in children and adults, and the central event is podocyte injury. INS is a heterogeneous disease, and treatment is largely empirical and in many cases unsuccessful, and steroids are the initial mainstay of therapy. Close to 70% of children with INS have some response to steroids and are labelled as steroid-‘sensitive’, and the rest as steroid-‘resistant’ (also termed focal segmental glomerulosclerosis), and single-gene mutations underlie a large proportion of the latter group. The burden of morbidity is enormous, both to patients with lifelong chronic disease and to health services, particularly in managing dialysis and transplantation. The target cell of nephrotic syndrome is the glomerular podocyte, and podocyte biology research has exploded over the last 15 years. Major advances in genetic and biological understanding now put clinicians and researchers at the threshold of a major reclassification of the disease and testing of targeted therapies both identified and novel. That potential is based on complete genetic analysis, deep clinical phenotyping, and the introduction of mechanism-derived biomarkers into clinical practice. INS can now be split off into those with a single-gene defect, of which currently at least 53 genes are known to be causative, and the others. Of the others, the majority are likely to be immune-mediated and caused by the presence of a still-unknown circulating factor or factors, and whether there is a third (or more) mechanistic group or groups remains to be discovered. Treatment is therefore now being refined towards separating out the monogenic cases to minimise immunosuppression and further understanding how best to stratify and appropriately direct immunosuppressive treatments within the immune group. Therapies directed specifically towards the target cell, the podocyte, are in their infancy but hold considerable promise for the near future. PMID

  13. Understanding advance care planning within the South Asian community.

    PubMed

    Biondo, Patricia D; Kalia, Rashika; Khan, Rooh-Afza; Asghar, Nadia; Banerjee, Cyrene; Boulton, Debbie; Marlett, Nancy; Shklarov, Svetlana; Simon, Jessica E

    2017-10-01

    Advance care planning (ACP) is a process of reflection on and communication of a person's future health-care preferences. Evidence suggests visible minorities engage less in ACP. The South Asian ethnic group is the largest visible minority group in Canada, and information is needed to understand how ACP is perceived and how best to approach ACP within this diverse community. To explore perspectives of South Asian community members towards ACP. Peer-to-peer inquiry. South Asian community members who graduated from the Patient and Community Engagement Research programme (PaCER) at the University of Calgary utilized the PaCER method (SET, COLLECT and REFLECT) to conduct a focus group, family interviews and a community forum. Fifty-seven community-dwelling men and women (22-86 years) who self-identified with the South Asian community in Calgary, Alberta, Canada. The concept of ACP was mostly foreign to this community and was often associated with other end-of-life issues such as organ donation and estate planning. Cultural aspects (e.g. trust in shared family decision making and taboos related to discussing death), religious beliefs (e.g. fatalism) and immigration challenges (e.g. essential priorities) emerged as barriers to participation in ACP. However, participants were eager to learn about ACP and recommended several engagement strategies (e.g. disseminate information through religious institutions and community centres, include families in ACP discussions, encourage family physicians to initiate discussions and translate materials). Use of a patient engagement research model proved highly successful in understanding South Asian community members' participation in ACP. © 2017 The Authors Health Expectations Published by John Wiley & Sons Ltd.

  14. Some recent advances in understanding the mineralogy of Earth's deep mantle.

    PubMed

    Duffy, Thomas S

    2008-11-28

    Understanding planetary structure and evolution requires a detailed knowledge of the properties of geological materials under the conditions of deep planetary interiors. Experiments under the extreme pressure-temperature conditions of the deep mantle are challenging, and many fundamental properties remain poorly constrained or are inferred only through uncertain extrapolations from lower pressure-temperature states. Nevertheless, the last several years have witnessed a number of new developments in this area, and a broad overview of the current understanding of the Earth's lower mantle is presented here. Some recent experimental and theoretical advances related to the lowermost mantle are highlighted. Measurements of the equation of state and deformation behaviour of (Mg,Fe)SiO3 in the CaIrO3-type (post-perovskite) structure yield insights into the nature of the core-mantle boundary region. Theoretical studies of the behaviour of MgSiO3 liquids under high pressure-temperature conditions provide constraints on melt volumes, diffusivities and viscosities that are relevant to understanding both the early Earth (e.g. deep magma oceans) and seismic structure observed in the present Earth (e.g. ultra-low-velocity zones).

  15. Some recent advances in understanding the mineralogy of Earth's deep mantle

    SciTech Connect

    Duffy, T S

    2008-12-09

    Understanding planetary structure and evolution requires a detailed knowledge of the properties of geological materials under the conditions of deep planetary interiors. Experiments under the extreme pressure-temperature conditions of the deep mantle are challenging, and many fundamental properties remain poorly constrained or are inferred only through uncertain extrapolations from lower pressure-temperature states. Nevertheless, the last several years have witnessed a number of new developments in this area, and a broad overview of the current understanding of the Earth's lower mantle is presented here. Some recent experimental and theoretical advances related to the lowermost mantle are highlighted. Measurements of the equation of state and deformation behaviour of (Mg,Fe)SiO{sub 3} in the CaIrO{sub 3}-type (post-perovskite) structure yield insights into the nature of the core-mantle boundary region. Theoretical studies of the behaviour of MgSiO3 liquids under high pressure-temperature conditions provide constraints on melt volumes, diffusivities and viscosities that are relevant to understanding both the early Earth (e.g. deep magma oceans) and seismic structure observed in the present Earth (e.g. ultra-low-velocity zones).

  16. Recent Advances in Understanding Enteric Pathogenic Escherichia coli

    PubMed Central

    Croxen, Matthew A.; Law, Robyn J.; Scholz, Roland; Keeney, Kristie M.; Wlodarska, Marta

    2013-01-01

    SUMMARY Although Escherichia coli can be an innocuous resident of the gastrointestinal tract, it also has the pathogenic capacity to cause significant diarrheal and extraintestinal diseases. Pathogenic variants of E. coli (pathovars or pathotypes) cause much morbidity and mortality worldwide. Consequently, pathogenic E. coli is widely studied in humans, animals, food, and the environment. While there are many common features that these pathotypes employ to colonize the intestinal mucosa and cause disease, the course, onset, and complications vary significantly. Outbreaks are common in developed and developing countries, and they sometimes have fatal consequences. Many of these pathotypes are a major public health concern as they have low infectious doses and are transmitted through ubiquitous mediums, including food and water. The seriousness of pathogenic E. coli is exemplified by dedicated national and international surveillance programs that monitor and track outbreaks; unfortunately, this surveillance is often lacking in developing countries. While not all pathotypes carry the same public health profile, they all carry an enormous potential to cause disease and continue to present challenges to human health. This comprehensive review highlights recent advances in our understanding of the intestinal pathotypes of E. coli. PMID:24092857

  17. Recent advances in understanding and managing psoriatic arthritis

    PubMed Central

    Gladman, Dafna D.

    2016-01-01

    This article reviews recent advances in psoriatic arthritis (PsA) over the past several years with emphasis on early diagnosis, better understanding of pathogenesis, and new therapeutic approaches. Early diagnosis is important, since people who present late do not fare as well. There are a number of clinical, laboratory, and ultrasound features that can help identify patients destined to develop PsA, and several screening tools have been developed. It is recognized that genetic and epigenetic factors, as well as T cells and cytokines, play a role in the pathogenesis of PsA, and several targets have been identified for therapeutic interventions. New therapies have been developed and tested in PsA and have been found to be highly effective for both skin and joint manifestations of the disease. The expectation is that, in the future, PsA patients will be treated early and more aggressively and that there will not be significant progression of joint damage. Moreover, with effective treatment of the skin and joint disease and management of risk factors for the comorbidities, we can expect to reduce their occurrence and further reduce the excess mortality and reduced quality of life and function in these patients. PMID:27928500

  18. Recent Advances in Understanding Audiovestibular Loss of a Vascular Cause

    PubMed Central

    Kim, Hyun-Ah; Lee, Hyung

    2017-01-01

    Acute audiovestibular loss is characterized by abrupt onset of prolonged (lasting days) vertigo and hearing loss. Acute ischemic stroke in the distribution of the anterior inferior cerebellar artery (AICA) is known to be the leading cause of acute audiovestibular loss. So far, eight subgroups of AICA territory infarction have been identified according to the patterns of audiovestibular dysfunctions, among which the most common pattern is the combined loss of auditory and vestibular functions. Unlike inner ear dysfunction of a viral cause, which can commonly present as an isolated vestibular (i.e., vestibular neuritis) or cochlear loss (i.e., sudden deafness), labyrinthine dysfunction of a vascular cause rarely results in isolated loss of vestibular or auditory function. As audiovestibular loss may precede the central symptoms or signs of an ischemic stroke in the posterior circulation, early diagnosis and proper management of audiovestiubular loss may provide a window to prevent the progression of infarction to larger areas of the posterior circulation. A clinician should consider the possibility that acute audiovestibular loss may herald impending AICA territory infarction, especially when patients have basilar artery occlusive disease close to the origin of the AICA on brain MRA. This review aims to highlight the recent advances in understanding audiovestibular loss of a vascular cause and to address its clinical significance. PMID:28030893

  19. An integrative theoretical framework for understanding sexual motivation, arousal, and behavior.

    PubMed

    Toates, Frederick

    2009-01-01

    An integrative theoretical framework and model for understanding sexual motivation, arousal, and behavior is presented, combining the principles of incentive motivation theory and the hierarchical control of behavior. It is intended to stimulate discussion. The framework can serve as a "route map" in understanding the links between different component processes and their interactions, as well as the relations between different academic perspectives on understanding sexuality. It is suggested that both excitation and inhibition of sexual motivation, arousal, and behavior act at various levels in a hierarchical structure, and much confusion can be avoided by distinguishing these levels. The model integrates information from different branches of psychology: biological, evolutionary, clinical, cognitive, developmental, and social. It describes interactions between sexual behavior and anxiety, attachment, aggression, and drug taking; and it is applied to gender differences, evolutionary psychology, sexual deviancy, sexual addiction, and the biological bases of sexuality.

  20. Bringing first-hand experience one step closer to theoretical understanding

    NASA Astrophysics Data System (ADS)

    Luo, Haoxiang; Myers, Mike; Luo's lab Team

    2016-11-01

    Many theoretical concepts and analytical approaches in fluid mechanics are challenging to teach. Classroom demos are very useful to engage and motivate students, but they do not necessarily lead straightforwardly to higher level understanding of model abstraction that is expressed with mathematical equations. To facilitate the process, we have designed a few demos and integrated them with quantitative measurements and theoretical analysis. These demos, usually generated from daily life examples, are of low cost and simple to implement, and the experimental procedures do not take significant time in a 50-min lecture. When combining them with classroom interactions, problem solving, and discussions, we found that these modules are effective in helping students in the learning process. Supported by the NSF.

  1. 48 CFR 1552.215-74 - Advanced understanding-uncompensated time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Advanced understanding... Clauses 1552.215-74 Advanced understanding—uncompensated time. As prescribed in 1515.408(b), insert the following provision or one substantially the same as the following provision: Advanced Understanding...

  2. Advancing Women Scientists: Exploring a Theoretically Grounded Climate Change Workshop Model

    NASA Astrophysics Data System (ADS)

    Silver, Barbara; Prochaska, Janice; Mederer, Helen; Harlow, Lisa; Sherman, Karen

    Universities in the United States have an increasing need to recruit the best and the brightest faculty to remain globally competitive, but the majority of schools share a profile that includes a low percentage of women in most of the science, technology, engineering, and math (STEM) disciplines. Changes in university culture are needed to enable departmental diversity growth, to expand offerings and perspectives, and to strengthen the view that STEM is an attractive choice for female students and prospective faculty. This paper describes the theoretical models used to develop a prototype workshop series implemented in departments to help faculty progress in their readiness to advance women scientists, defined as collaborating, mentoring, sharing resources, and generating support through community. The three theoretical underpinnings are the gender-as-structure theory of organizational change, Appreciative Inquiry, and the Transtheoretical Model. These workshops are one aspect of the climate change efforts implemented by the ADVANCE program of the University of Rhode Island.

  3. Cultural Psychology of Differences and EMS; a New Theoretical Framework for Understanding and Reconstructing Culture.

    PubMed

    Yamamoto, Toshiya

    2017-09-01

    In this paper I introduce the outlines of our new type of theoretical framework named 'Cultural psychology of Differences' for understanding cultural others and dialogically reconstructing interactions among cultural others. In order to understand cultural others, it is necessary for us to reconstruct a new concept which enables us to analyze dynamic generation processes of culture. We propose the concept of Expanded Mediational Structure, EMS, as an elementary unit for understanding human social interactions. EMS is composed of subjects who interacts each other using objects of some kind as mediators, and a normative mediator, NM, which mediates their interactions. It is necessary to generate, share and adjust a NM to keep social interactions stable, and culture will appear when interaction malfunction is attributed to a gaps of NMs. The concept of EMS helps us to understand how culture is functionally substantialized in the plane of collective (or communal) intersubjectivity and how cultural conflicts develop and intensify. Focusing on the generation process of culture through interactions provides us with another option to understand cultural others through dialogical interactions with them.

  4. The impact of recent advances in laboratory astrophysics on our understanding of the cosmos.

    PubMed

    Savin, D W; Brickhouse, N S; Cowan, J J; Drake, R P; Federman, S R; Ferland, G J; Frank, A; Gudipati, M S; Haxton, W C; Herbst, E; Profumo, S; Salama, F; Ziurys, L M; Zweibel, E G

    2012-03-01

    An emerging theme in modern astrophysics is the connection between astronomical observations and the underlying physical phenomena that drive our cosmos. Both the mechanisms responsible for the observed astrophysical phenomena and the tools used to probe such phenomena-the radiation and particle spectra we observe-have their roots in atomic, molecular, condensed matter, plasma, nuclear and particle physics. Chemistry is implicitly included in both molecular and condensed matter physics. This connection is the theme of the present report, which provides a broad, though non-exhaustive, overview of progress in our understanding of the cosmos resulting from recent theoretical and experimental advances in what is commonly called laboratory astrophysics. This work, carried out by a diverse community of laboratory astrophysicists, is increasingly important as astrophysics transitions into an era of precise measurement and high fidelity modeling.

  5. Students' Understanding of Advanced Properties of Java Exceptions

    ERIC Educational Resources Information Center

    Rashkovits, Rami; Lavy, Ilana

    2012-01-01

    This study examines how Information Systems Engineering School students on the verge of their graduation understand the mechanism of exception handling. The main contributions of this paper are as follows: we construct a questionnaire aimed at examining students' level of understanding concerning exceptions; we classify and analyse the students'…

  6. Recent Advances in Understanding, Diagnosing, and Treating Ovarian Cancer

    PubMed Central

    Mills, Kathryn; Fuh, Katherine

    2017-01-01

    Ovarian cancer, a term that encompasses ovarian, fallopian, and peritoneal cancers, is the leading cause of gynecologic cancer mortality. To improve patient outcomes, the field is currently focused on defining the mechanisms of cancer formation and spread, early diagnosis and prevention, and developing novel therapeutic options. This review summarizes recent advances in these areas. PMID:28184293

  7. Where is the Theoretical Basis for Understanding and Measuring the Environment for Physical Activity?

    PubMed

    Nelson, N M; Wright, A; Lowry, R G; Mutrie, N

    2008-12-02

    Researchers are beginning to explore environmental correlates to further the field of physical activity research. Before interventions and experimental investigations can be undertaken, it is necessary to identify specific environmental features that are consistent correlates of physical activity. There has been a plethora of research measuring such cross-sectional associations since this field came to the fore in 2003. This paper posits that it is time for researchers to evaluate the state of knowledge, and suggests that future developments in this field focus on the theoretical bases for (i) measurement of the environment and (ii) understanding the links between perceptions of the environment and behaviour through psychological theories of cognition. Key theories considered include social ecology and the theory of planned behaviour. It is suggested that with a continued absence of a common conceptual framework, vocabulary and measurement tools the majority of studies may remain at a correlates stage. In highlighting issues with current methodologies, this commentary encourages more grounded theoretical approaches to the study of the environment and physical activity.

  8. Personality is of central concern to understand health: towards a theoretical model for health psychology

    PubMed Central

    Ferguson, Eamonn

    2013-01-01

    This paper sets out the case that personality traits are central to health psychology. To achieve this, three aims need to be addressed. First, it is necessary to show that personality influences a broad range of health outcomes and mechanisms. Second, the simple descriptive account of Aim 1 is not sufficient, and a theoretical specification needs to be developed to explain the personality-health link and allow for future hypothesis generation. Third, once Aims 1 and 2 are met, it is necessary to demonstrate the clinical utility of personality. In this review I make the case that all three Aims are met. I develop a theoretical framework to understand the links between personality and health drawing on current theorising in the biology, evolution, and neuroscience of personality. I identify traits (i.e., alexithymia, Type D, hypochondriasis, and empathy) that are of particular concern to health psychology and set these within evolutionary cost-benefit analysis. The literature is reviewed within a three-level hierarchical model (individual, group, and organisational) and it is argued that health psychology needs to move from its traditional focus on the individual level to engage group and organisational levels. PMID:23772230

  9. Manganese: Recent advances in understanding its transport and neurotoxicity

    SciTech Connect

    Aschner, Michael . E-mail: Michael.Aschner@vanderbilt.edu; Guilarte, Tomas R.; Schneider, Jay S.; Zheng Wei

    2007-06-01

    The present review is based on presentations from the meeting of the Society of Toxicology in San Diego, CA (March 2006). It addresses recent developments in the understanding of the transport of manganese (Mn) into the central nervous system (CNS), as well as brain imaging and neurocognitive studies in non-human primates aimed at improving our understanding of the mechanisms of Mn neurotoxicity. Finally, we discuss potential therapeutic modalities for treating Mn intoxication in humans.

  10. Understanding effects in reviews of implementation interventions using the Theoretical Domains Framework.

    PubMed

    Little, Elizabeth A; Presseau, Justin; Eccles, Martin P

    2015-06-17

    Behavioural theory can be used to better understand the effects of behaviour change interventions targeting healthcare professional behaviour to improve quality of care. However, the explicit use of theory is rarely reported despite interventions inevitably involving at least an implicit idea of what factors to target to implement change. There is a quality of care gap in the post-fracture investigation (bone mineral density (BMD) scanning) and management (bisphosphonate prescription) of patients at risk of osteoporosis. We aimed to use the Theoretical Domains Framework (TDF) within a systematic review of interventions to improve quality of care in post-fracture investigation. Our objectives were to explore which theoretical factors the interventions in the review may have been targeting and how this might be related to the size of the effect on rates of BMD scanning and osteoporosis treatment with bisphosphonate medication. A behavioural scientist and a clinician independently coded TDF domains in intervention and control groups. Quantitative analyses explored the relationship between intervention effect size and total number of domains targeted, and as number of different domains targeted. Nine randomised controlled trials (RCTs) (10 interventions) were analysed. The five theoretical domains most frequently coded as being targeted by the interventions in the review included "memory, attention and decision processes", "knowledge", "environmental context and resources", "social influences" and "beliefs about consequences". Each intervention targeted a combination of at least four of these five domains. Analyses identified an inverse relationship between both number of times and number of different domains coded and the effect size for BMD scanning but not for bisphosphonate prescription, suggesting that the more domains the intervention targeted, the lower the observed effect size. When explicit use of theory to inform interventions is absent, it is possible to

  11. Theoretical investigation of loratadine reactivity in order to understand its degradation properties: DFT and MD study.

    PubMed

    Armaković, Stevan; Armaković, Sanja J; Abramović, Biljana F

    2016-10-01

    Antihistamines are frequently used pharmaceuticals that treat the symptoms of allergic reactions. Loratadine (LOR) is an active component of the second generation of selective antihistaminic pharmaceutical usually known as Claritin. Frequent usage of this type of pharmaceuticals imposes the need for understanding their fundamental reactive properties. In this study we have theoretically investigated reactive properties of LOR using both density functional theory (DFT) calculations and molecular dynamics (MD) simulations. DFT study is used for collecting information related to the molecule stability, structure, frontier molecular orbitals, quantum molecular descriptors, charge distribution, molecular electrostatic potential surfaces, charge polarization, and local reactivity properties according to average local ionization energy surfaces. Based on these results, N24 atom of pyridine ring and oxygen atom O1 were identified with nucleophilic nature. In order to collect the information necessary for the proposition of degradation compounds we also calculated bond dissociation energies (BDE) for hydrogen abstraction and single acyclic bonds as well. According to BDE, the oxidation is likely to occur in the piperidine and cycloheptane rings. MD simulations were used in order to understand the interactions with water through radial distribution functions (RDF). Based on RDFs the most important interactions with solvent are determined for carbon atom C5, chlorine atom Cl15, and oxygen atom O1. Collected results based on DFT calculations and MD simulations provided information important for suggestion of possible degradation compounds. Covalent and noncovalent interactions between LOR and (•)OH have also been investigated.

  12. A Theoretical Approach to Understanding Population Dynamics with Seasonal Developmental Durations

    NASA Astrophysics Data System (ADS)

    Lou, Yijun; Zhao, Xiao-Qiang

    2017-04-01

    There is a growing body of biological investigations to understand impacts of seasonally changing environmental conditions on population dynamics in various research fields such as single population growth and disease transmission. On the other side, understanding the population dynamics subject to seasonally changing weather conditions plays a fundamental role in predicting the trends of population patterns and disease transmission risks under the scenarios of climate change. With the host-macroparasite interaction as a motivating example, we propose a synthesized approach for investigating the population dynamics subject to seasonal environmental variations from theoretical point of view, where the model development, basic reproduction ratio formulation and computation, and rigorous mathematical analysis are involved. The resultant model with periodic delay presents a novel term related to the rate of change of the developmental duration, bringing new challenges to dynamics analysis. By investigating a periodic semiflow on a suitably chosen phase space, the global dynamics of a threshold type is established: all solutions either go to zero when basic reproduction ratio is less than one, or stabilize at a positive periodic state when the reproduction ratio is greater than one. The synthesized approach developed here is applicable to broader contexts of investigating biological systems with seasonal developmental durations.

  13. Moral distress: a comparative analysis of theoretical understandings and inter-related concepts.

    PubMed

    Lützén, Kim; Kvist, Beatrice Ewalds

    2012-03-01

    Research on ethical dilemmas in health care has become increasingly salient during the last two decades resulting in confusion about the concept of moral distress. The aim of the present paper is to provide an overview and a comparative analysis of the theoretical understandings of moral distress and related concepts. The focus is on five concepts: moral distress, moral stress, stress of conscience, moral sensitivity and ethical climate. It is suggested that moral distress connects mainly to a psychological perspective; stress of conscience more to a theological-philosophical standpoint; and moral stress mostly to a physiological perspective. Further analysis indicates that these thoughts can be linked to the concepts of moral sensitivity and ethical climate through a relationship to moral agency. Moral agency comprises a moral awareness of moral problems and moral responsibility for others. It is suggested that moral distress may serve as a positive catalyst in exercising moral agency. An interdisciplinary approach in research and practice broadens our understanding of moral distress and its impact on health care personnel and patient care.

  14. Advances in understanding glycosyltransferases from a structural perspective

    PubMed Central

    Gloster, Tracey M

    2014-01-01

    Glycosyltransferases (GTs), the enzymes that catalyse glycosidic bond formation, create a diverse range of saccharides and glycoconjugates in nature. Understanding GTs at the molecular level, through structural and kinetic studies, is important for gaining insights into their function. In addition, this understanding can help identify those enzymes which are involved in diseases, or that could be engineered to synthesize biologically or medically relevant molecules. This review describes how structural data, obtained in the last 3–4 years, have contributed to our understanding of the mechanisms of action and specificity of GTs. Particular highlights include the structure of a bacterial oligosaccharyltransferase, which provides insights into N-linked glycosylation, the structure of the human O-GlcNAc transferase, and the structure of a bacterial integral membrane protein complex that catalyses the synthesis of cellulose, the most abundant organic molecule in the biosphere. PMID:25240227

  15. A Hydrological Perspective to Advance Understanding of the Water Cycle

    NASA Astrophysics Data System (ADS)

    Berghuijs, W.

    2014-12-01

    In principle hydrologists are scientists that study relationships within the water cycle. Yet, current technology makes it tempting for hydrology students to lose their "hydrological perspective" and become instead full-time computer programmers or statisticians. I assert that students should ensure their hydrological perspective thrives, notwithstanding the importance and possibilities of current technology. This perspective is necessary to advance the science of hydrology. As other hydrologists have pondered similar views before, I make no claims of originality here. I just hope that in presenting my perspective on this issue I may spark the interest of other early career hydrologists.

  16. A simple theoretical framework for understanding heterogeneous differentiation of CD4+ T cells

    PubMed Central

    2012-01-01

    Background CD4+ T cells have several subsets of functional phenotypes, which play critical yet diverse roles in the immune system. Pathogen-driven differentiation of these subsets of cells is often heterogeneous in terms of the induced phenotypic diversity. In vitro recapitulation of heterogeneous differentiation under homogeneous experimental conditions indicates some highly regulated mechanisms by which multiple phenotypes of CD4+ T cells can be generated from a single population of naïve CD4+ T cells. Therefore, conceptual understanding of induced heterogeneous differentiation will shed light on the mechanisms controlling the response of populations of CD4+ T cells under physiological conditions. Results We present a simple theoretical framework to show how heterogeneous differentiation in a two-master-regulator paradigm can be governed by a signaling network motif common to all subsets of CD4+ T cells. With this motif, a population of naïve CD4+ T cells can integrate the signals from their environment to generate a functionally diverse population with robust commitment of individual cells. Notably, two positive feedback loops in this network motif govern three bistable switches, which in turn, give rise to three types of heterogeneous differentiated states, depending upon particular combinations of input signals. We provide three prototype models illustrating how to use this framework to explain experimental observations and make specific testable predictions. Conclusions The process in which several types of T helper cells are generated simultaneously to mount complex immune responses upon pathogenic challenges can be highly regulated, and a simple signaling network motif can be responsible for generating all possible types of heterogeneous populations with respect to a pair of master regulators controlling CD4+ T cell differentiation. The framework provides a mathematical basis for understanding the decision-making mechanisms of CD4+ T cells, and it can be

  17. Understanding the operational environment: implications for advanced visualizations

    NASA Astrophysics Data System (ADS)

    Aleva, Denise; Fitzhugh, Elisabeth; Dixon, Sharon

    2009-05-01

    With the changing character of warfare, information superiority is a high priority. Given the complexity of current and future operating environments, analysts, strategists and planners need a multidimensional understanding of the battlespace. Asymmetric warfare necessitates that our strategists look beyond targets-based operations, where we simply identify and destroy enemy entities. Effects-based operations models the enemy as a system which reacts to our actions. This requires the capability to predict the adversary response to a selected action. Actions may be diplomatic, information, military or economic (DIME). Effects may be political, military, economic, social, information or infrastructure (PMESII). Timing must be explicitly considered and effects dynamically assessed. Visualizations of intelligence information are needed which will promote full understanding of all aspects of adversary strengths and weaknesses by providing the extensive data about adversary forces, organic essentials, infrastructure, leadership, population, and science and technology in an easily accessible and understandable format. This will enhance Effectsbased operations, and therefore, the capability to predict and counter adversary courses of action. This paper outlines a systems engineering approach to designing visualizations which convey the multidimensional information to decision makers. Visualization issues inherent in understanding the multidimensional operational environment will be discussed.

  18. Advancing our understanding of charcoal rot in soybeans

    USDA-ARS?s Scientific Manuscript database

    Charcoal rot (Macrophomina phaseolina (Tassi) Goid ) of soybean [Glycine max (L.) Merr.], is an important but commonly misidentified disease, and very few summary articles exist on this pathosystem. Research conducted over the last 10 years has improved our understanding of the environment conducive...

  19. New advances in understanding decisions among multiple alternatives.

    PubMed

    Churchland, Anne K; Ditterich, Jochen

    2012-12-01

    Experimental studies of decision-making have put a strong emphasis on choices between two alternatives. However, real-life decisions often involve multiple alternatives. This article provides an overview of theoretical frameworks that have been proposed to account for behavioral data from both economic and perceptual multialternative decision-making. We further review recent neurophysiological data collected in conjunction with decision-making behavior. These neural recordings provide constraints on putative models of the decision mechanism. For example, the time course of inhibition provides insight into how the competition between alternatives is mediated. Furthermore, whereas decision-related neural activity seems to reach a common threshold at the end of the decision period, the starting point tends to depend systematically on the number of alternatives. We discuss candidate mechanisms that could drive the reduction in firing rates on decisions among multiple alternatives.

  20. Cancer surviving patients' rehabilitation – understanding failure through application of theoretical perspectives from Habermas

    PubMed Central

    Mikkelsen, Thorbjørn H; Soendergaard, Jens; Jensen, Anders B; Olesen, Frede

    2008-01-01

    This study aims to analyze whether the rehabilitation of cancer surviving patients (CSPs) can be better organized. The data for this paper consists of focus group interviews (FGIs) with CSPs, general practitioners (GPs) and hospital physicians. The analysis draws on the theoretical framework of Jürgen Habermas, utilizing his notions of 'the system and the life world' and 'communicative and strategic action'. In Habermas' terminology, the social security system and the healthcare system are subsystems that belong to what he calls the 'system', where actions are based on strategic actions activated by the means of media such as money and power which provide the basis for other actors' actions. The social life, on the other hand, in Habermas' terminology, belongs to what he calls the 'life world', where communicative action is based on consensual coordination among individuals. Our material suggests that, within the hospital world, the strategic actions related to diagnosis, treatment and cure in the biomedical discourse dominate. They function as inclusion/exclusion criteria for further treatment. However, the GPs appear to accept the CSPs' previous cancer diagnosis as a precondition sufficient for providing assistance. Although the GPs use the biomedical discourse and often give biomedical examples to exemplify rehabilitation needs, they find psychosocial aspects, so-called lifeworld aspects, to be an important component of their job when helping CSPs. In this way, they appear more open to communicative action in relation to the CSPs' lifeworld than do the hospital physicians. Our data also suggests that the CSPs' lifeworld can be partly colonized by the system during hospitalization, making it difficult for CSPs when they are discharged at the end of treatment. This situation seems to be crucial to our understanding of why CSPs often feel left in limbo after discharge. We conclude that the distinction between the system and the lifeworld and the implications of a

  1. Cancer surviving patients' rehabilitation - understanding failure through application of theoretical perspectives from Habermas.

    PubMed

    Mikkelsen, Thorbjørn H; Soendergaard, Jens; Jensen, Anders B; Olesen, Frede

    2008-06-06

    This study aims to analyze whether the rehabilitation of cancer surviving patients (CSPs) can be better organized. The data for this paper consists of focus group interviews (FGIs) with CSPs, general practitioners (GPs) and hospital physicians. The analysis draws on the theoretical framework of Jürgen Habermas, utilizing his notions of 'the system and the life world' and 'communicative and strategic action'. In Habermas' terminology, the social security system and the healthcare system are subsystems that belong to what he calls the 'system', where actions are based on strategic actions activated by the means of media such as money and power which provide the basis for other actors' actions. The social life, on the other hand, in Habermas' terminology, belongs to what he calls the 'life world', where communicative action is based on consensual coordination among individuals. Our material suggests that, within the hospital world, the strategic actions related to diagnosis, treatment and cure in the biomedical discourse dominate. They function as inclusion/exclusion criteria for further treatment. However, the GPs appear to accept the CSPs' previous cancer diagnosis as a precondition sufficient for providing assistance. Although the GPs use the biomedical discourse and often give biomedical examples to exemplify rehabilitation needs, they find psychosocial aspects, so-called lifeworld aspects, to be an important component of their job when helping CSPs. In this way, they appear more open to communicative action in relation to the CSPs' lifeworld than do the hospital physicians. Our data also suggests that the CSPs' lifeworld can be partly colonized by the system during hospitalization, making it difficult for CSPs when they are discharged at the end of treatment. This situation seems to be crucial to our understanding of why CSPs often feel left in limbo after discharge. We conclude that the distinction between the system and the lifeworld and the implications of a

  2. Recent advances in understanding Pseudomonas aeruginosa as a pathogen

    PubMed Central

    Klockgether, Jens; Tümmler, Burkhard

    2017-01-01

    The versatile and ubiquitous Pseudomonas aeruginosa is an opportunistic pathogen causing acute and chronic infections in predisposed human subjects. Here we review recent progress in understanding P. aeruginosa population biology and virulence, its cyclic di-GMP-mediated switches of lifestyle, and its interaction with the mammalian host as well as the role of the type III and type VI secretion systems in P. aeruginosa infection. PMID:28794863

  3. Advances in understanding the interrelations between leptin resistance and obesity.

    PubMed

    Pan, Haitao; Guo, Jiao; Su, Zhengquan

    2014-05-10

    Obesity, which has developed into a global epidemic, is a risk factor in most chronic diseases and some forms of malignancy. The discovery of leptin in 1994 has opened a new field in obesity research. Currently, we know that leptin is the primary signal from energy stores and exerts negative feedback effects on energy intake. However, most individuals with diet-induced obesity (DIO) develop leptin resistance, which is characterized by elevated circulating leptin levels and decreased leptin sensitivity. To date, though various mechanisms have been proposed to explain leptin resistance, the exact mechanisms of leptin resistance in obesity are poorly understood. Consequently, it's an important issue worth discussing regarding what the exact interrelations between leptin resistance and obesity are. Here, we review the latest advancements in the molecular mechanisms of leptin resistance and the exact interrelations between leptin resistance, obesity, and obesity-related diseases, in order to supply new ideas for the study of obesity.

  4. Advances in understanding Giardia: determinants and mechanisms of chronic sequelae

    PubMed Central

    Sartor, R. Balfour

    2015-01-01

    Giardia lamblia is a flagellated protozoan that is the most common cause of intestinal parasitic infection in children living in resource-limited settings. The pathogenicity of Giardia has been debated since the parasite was first identified, and clinical outcomes vary across studies. Among recent perplexing findings are diametrically opposed associations between Giardia and acute versus persistent diarrhea and a poorly understood potential for long-term sequelae, including impaired child growth and cognitive development. The mechanisms driving these protean clinical outcomes remain elusive, but recent advances suggest that variability in Giardia strains, host nutritional status, the composition of microbiota, co-infecting enteropathogens, host genetically determined mucosal immune responses, and immune modulation by Giardia are all relevant factors influencing disease manifestations after Giardia infection. PMID:26097735

  5. Scratching the itch: new tools to advance understanding of scabies.

    PubMed

    Mounsey, Kate E; McCarthy, James S; Walton, Shelley F

    2013-01-01

    Scabies remains a significant public health problem worldwide. Research into aspects of Sarcoptes scabiei biology and host-parasite interactions has been impeded by an inability to maintain mites in vitro and by limited access to parasite material and infected subjects. The generation of comprehensive expressed sequence tag libraries has enabled the initial characterisation of molecules of interest to diagnostics, vaccines, and drug resistance. The recent development and utilisation of animal models, combined with next-generation technologies, is anticipated to lead to new strategies to prevent, diagnose, and treat scabies, ultimately improving skin health in both human and veterinary settings. This article will summarise recent molecular and immunologic advances on scabies, and will address priorities for the exciting 'next chapter' of scabies research. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Recent advances in understanding haemochromatosis: a transition state

    PubMed Central

    Robson, K; Merryweather-Clar..., A; Cadet, E; Viprakasit, V; Zaahl, M; Pointon, J; Weatherall, D; Rochette, J

    2004-01-01

    Mutations in the hepcidin gene HAMP and the hemojuvelin gene HJV have recently been shown to result in juvenile haemochromatosis (JH). Hepcidin is an antimicrobial peptide that plays a key role in regulating intestinal iron absorption. Hepcidin levels are reduced in patients with haemochromatosis due to mutations in the HFE and HJV genes. Digenic inheritance of mutations in HFE and HAMP can result in either JH or hereditary haemochromatosis (HH) depending upon the severity of the mutation in HAMP. Here we review these findings and discuss how understanding the different types of haemochromatosis and our increasing knowledge of iron metabolism may help to elucidate the host's response to infection. PMID:15466004

  7. Advances in the understanding and behavioural management of sexual dysfunctions.

    PubMed

    Rao, Telkar Srinivasa Sathyanarayana; Tandon, Abhinav

    2014-09-01

    Sexual medicine is a branch often neglected by professionals from different specialties associated with it. However, research in this field has picked up in recent years, owing to recently renewed interest in upholding the sexual rights of the population in general and lesbian, gay, bisexual and transgender groups in particular. The recently released Diagnostic and statistical manual of mental disorders, fifth edition, by the American Psychiatric Association in May 2013 has stirred up the supporters and critics (of Diagnostic and statistical manual of mental disorders, fifth edition) alike. Diagnostic and statistical manual of mental disorders, fifth edition, has updated diagnostic criteria for some of the sexual disorders to improve understanding and diagnostic validity. Certain sexual dysfunctions have been regrouped and sexual response cycle-based classification has been partially withdrawn. Research in the area of behavioral management of sexual dysfunctions has given some novel concepts, particularly for women. Although improvements in behavioral management (of sexual dysfunctions) and classification/diagnostic criteria in Diagnostic and statistical manual of mental disorders, fifth edition, is a step forward in the field of sexual medicine, we need to further improve our understanding in many of the lacunae, still bearing on the field of sexual medicine, lest we may fall at the first hurdle.

  8. Theoretical Understanding of Enhanced Proton Energies from Laser-Cone Interactions

    SciTech Connect

    Kluge, T.; Gaillard, S. A.; Bussmann, M.; Burris-Mog, T.; Kraft, S. D.; Metzkes, J.; Rassuchine, J.; Schramm, U.; Zeil, K.; Cowan, T. E.; Flippo, K. A.; Offermann, D. T.; Gall, B.; Geissel, M.; Schollmeier, M.; Lockard, T.; Sentoku, Y.

    2010-11-04

    For the past ten years, the highest proton energies accelerated with high-intensity lasers was 58 MeV, observed in 2000 at the LLNL NOVA Petawatt laser, using flat foil targets. Recently, 67.5 MeV protons were observed in experiments at the Los Alamos National Laboratory (LANL) Trident laser, using one-fifth of the PW laser pulse energy, incident into novel conical targets. We present a focused study of new theoretical understanding of this measured enhancement from collisional Particle-in-Cell simulations, which shows that the hot electron temperature, number and maximum energy, responsible for the Target Normal Sheath Acceleration (TNSA) at the cone-top, are significantly increased when the laser grazes the cone wall. This is mainly due to the extraction of electrons from the cone wall by the laser electric field, and their boost in the forward direction by the vxB term of the Lorentz force. This result is in contrast to previous predictions of optical collection and wall-guiding of electrons in angled cones. This new wall-grazing mechanism offers the prospect to linearly increase the hot electron temperature, and thereby the TNSA proton energy, by extending the length over which the laser interacts in a grazing fashion in suitably optimized targets. This may allow achieving much higher proton energies for interesting future applications, with smaller, lower energy laser systems that allow for a high repetition rate.

  9. Geoscience Academic Provenance: A Theoretical Framework for Understanding Geoscience Students' Pathways

    NASA Astrophysics Data System (ADS)

    Houlton, H.; Keane, C.

    2012-04-01

    The demand and employment opportunities for geoscientists in the United States are projected to increase 23% from 2008 to 2018 (Gonzales, 2011). Despite this trend, there is a disconnect between undergraduate geoscience students and their desire to pursue geoscience careers. A theoretical framework was developed to understand the reasons why students decide to major in the geosciences and map those decisions to their career aspirations (Houlton, 2010). A modified critical incident study was conducted to develop the pathway model from 17, one-hour long semi-structured interviews of undergraduate geoscience majors from two Midwest Research Institutions (Houlton, 2010). Geoscience Academic Provenance maps geoscience students' initial interests, entry points into the major, critical incidents and future career goals as a pathway, which elucidates the relationships between each of these components. Analyses identified three geoscience student population groups that followed distinct pathways: Natives, Immigrants and Refugees. A follow up study was conducted in 2011 to ascertain whether these students continued on their predicted pathways, and if not, reasons for attrition. Geoscientists can use this framework as a guide to inform future recruitment and retention initiatives and target these geoscience population groups for specific employment sectors.

  10. Force-induced bone growth and adaptation: A system theoretical approach to understanding bone mechanotransduction

    NASA Astrophysics Data System (ADS)

    Maldonado, Solvey; Findeisen, Rolf

    2010-06-01

    The modeling, analysis, and design of treatment therapies for bone disorders based on the paradigm of force-induced bone growth and adaptation is a challenging task. Mathematical models provide, in comparison to clinical, medical and biological approaches an structured alternative framework to understand the concurrent effects of the multiple factors involved in bone remodeling. By now, there are few mathematical models describing the appearing complex interactions. However, the resulting models are complex and difficult to analyze, due to the strong nonlinearities appearing in the equations, the wide range of variability of the states, and the uncertainties in parameters. In this work, we focus on analyzing the effects of changes in model structure and parameters/inputs variations on the overall steady state behavior using systems theoretical methods. Based on an briefly reviewed existing model that describes force-induced bone adaptation, the main objective of this work is to analyze the stationary behavior and to identify plausible treatment targets for remodeling related bone disorders. Identifying plausible targets can help in the development of optimal treatments combining both physical activity and drug-medication. Such treatments help to improve/maintain/restore bone strength, which deteriorates under bone disorder conditions, such as estrogen deficiency.

  11. The growth threshold conjecture: a theoretical framework for understanding T-cell tolerance.

    PubMed

    Arias, Clemente F; Herrero, Miguel A; Cuesta, José A; Acosta, Francisco J; Fernández-Arias, Cristina

    2015-07-01

    Adaptive immune responses depend on the capacity of T cells to target specific antigens. As similar antigens can be expressed by pathogens and host cells, the question naturally arises of how can T cells discriminate friends from foes. In this work, we suggest that T cells tolerate cells whose proliferation rates remain below a permitted threshold. Our proposal relies on well-established facts about T-cell dynamics during acute infections: T-cell populations are elastic (they expand and contract) and they display inertia (contraction is delayed relative to antigen removal). By modelling inertia and elasticity, we show that tolerance to slow-growing populations can emerge as a population-scale feature of T cells. This result suggests a theoretical framework to understand immune tolerance that goes beyond the self versus non-self dichotomy. It also accounts for currently unexplained observations, such as the paradoxical tolerance to slow-growing pathogens or the presence of self-reactive T cells in the organism.

  12. The growth threshold conjecture: a theoretical framework for understanding T-cell tolerance

    PubMed Central

    Arias, Clemente F.; Herrero, Miguel A.; Cuesta, José A.; Acosta, Francisco J.; Fernández-Arias, Cristina

    2015-01-01

    Adaptive immune responses depend on the capacity of T cells to target specific antigens. As similar antigens can be expressed by pathogens and host cells, the question naturally arises of how can T cells discriminate friends from foes. In this work, we suggest that T cells tolerate cells whose proliferation rates remain below a permitted threshold. Our proposal relies on well-established facts about T-cell dynamics during acute infections: T-cell populations are elastic (they expand and contract) and they display inertia (contraction is delayed relative to antigen removal). By modelling inertia and elasticity, we show that tolerance to slow-growing populations can emerge as a population-scale feature of T cells. This result suggests a theoretical framework to understand immune tolerance that goes beyond the self versus non-self dichotomy. It also accounts for currently unexplained observations, such as the paradoxical tolerance to slow-growing pathogens or the presence of self-reactive T cells in the organism. PMID:26587263

  13. Recent advances in our understanding of Streptococcus pneumoniae infection

    PubMed Central

    Anderson, Ronald

    2014-01-01

    A number of significant challenges remain with regard to the diagnosis, treatment, and prevention of infections with Streptococcus pneumoniae (pneumococcus), which remains the most common bacterial cause of community-acquired pneumonia. Although this infection is documented to be extremely common in younger children and in older adults, the burden of pneumonia it causes is considerably underestimated, since the incidence statistics are derived largely from bacteremic infections, because they are easy to document, and yet the greater burden of pneumococcal pneumonias is non-invasive. It has been estimated that for every bacteremic pneumonia that is documented, three non-bacteremic infections occur. Management of these infections is potentially complicated by the increasing resistance of the isolates to the commonly used antibiotics. Furthermore, it is well recognized that despite advances in medical care, the mortality of bacteremic pneumococcal pneumonia has remained largely unchanged over the past 50 years and averages approximately 12%. Much recent research interest in the field of pneumococcal infections has focused on important virulence factors of the organism, on improved diagnostic and prognostication tools, on defining risk factors for death, on optimal treatment strategies involving both antibiotics and adjunctive therapies, and on disease prevention. It is hoped that through these endeavors the outlook of pneumococcal infections will be improved. PMID:25343039

  14. Advances in understanding the gravity wave spectrum during MAP

    NASA Technical Reports Server (NTRS)

    Vanzandt, T. E.

    1989-01-01

    Prior to MAP, virtually nothing was known about gravity wave spectra in the atmosphere. The development of observational techniques has played a major role in these studies. Radar and lidar have been particularly important since they can measure atmospheric parameters continuously over large height ranges. Some advances made are: (1) The observed fluctuations and power spectra in the free atmosphere are mostly if not entirely due to a superposition of gravity waves, which can be modeled by the Garrett Munk (GM) model; (2) There is no evidence that 2-D turbulence makes a significant contribution to the observed fluctuations. In any case, the agreement between observations and the GM model shows that the 2DT contribution must be relatively small; (3) Spectra versus vertical wave number are saturated at large wave number, with theory and observations indicating that t approximately equals 3; and (4) Vertical velocity fluctuations and spectra measured near rough terrain are strongly contaminated by mountain waves. But over very flat terrain the spectra are dominated by gravity waves at periods shorter than about 6 hours and apparently by synoptic scale velocities at periods longer than 6 hours. Thus it may be possible to study synoptic scale vertical velocities using radars located in very flat terrain.

  15. Recent advances in understanding and managing body dysmorphic disorder

    PubMed Central

    Krebs, Georgina; Fernández de la Cruz, Lorena; Mataix-Cols, David

    2017-01-01

    Body dysmorphic disorder (BDD) is a relatively common and disabling psychiatric disorder characterised by excessive and persistent preoccupation with perceived defects or flaws in one's appearance, which are unnoticeable to others, and associated repetitive behaviours (eg, mirror checking). The disorder generally starts in adolescence, but often goes unnoticed and is severely underdiagnosed. Left untreated, BDD typically persists and causes marked functional impairment in multiple domains. This clinical review considers recent advances in the epidemiology and classification of BDD, including its reclassification in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders under the new ‘Obsessive–Compulsive and Related Disorders’ chapter. Key issues in assessment are outlined including the use of validated screening instruments to minimise misdiagnosis and the importance of risk assessment in this population given the high rates of suicidality and inappropriate use of cosmetic treatments. In addition, current knowledge regarding the causes and mechanisms underlying BDD are summarised. The recommended treatments for BDD are outlined, namely cognitive behavioural therapy (CBT) and antidepressants, such as selective serotonin reuptake inhibitors. Both CBT and pharmacotherapy have been shown to be efficacious treatments for BDD in adult populations, and evidence is emerging to support their use in young people. Although the majority of patients improve with existing evidence-based treatment, a large proportion are left with clinically significant residual symptoms. Priorities for future research are therefore discussed including the need to further refine and evaluate existing interventions with the goal of improving treatment outcomes and to increase their availability. PMID:28729345

  16. Proteomics Advances in the Understanding of Pollen–Pistil Interactions

    PubMed Central

    Fu, Ziyang; Yang, Pingfang

    2014-01-01

    The first key point to the successful pollination and fertilization in plants is the pollen-pistil interaction, referring to the cellular and molecular levels, which mainly involve the haploid pollen and the diploid pistil. The process is defined as “siphonogamy”, which starts from the capture of pollen by the epidermis of stigma and ends up with the fusion of sperm with egg. So far, the studies of the pollen-pistil interaction have been explicated around the self-compatibility and self-incompatibility (SI) process in different species from the molecular genetics and biochemistry to cellular and signal levels, especially the mechanism of SI system. Among them, numerous proteomics studies based on the advanced technologies from gel-system to gel-free system were conducted, focusing on the interaction, in order to uncover the mechanism of the process. The current review mainly focuses on the recent developments in proteomics of pollen-pistil interaction from two aspects: self-incompatible and compatible pollination. It might provide a comprehensive insight on the proteins that were involved in the regulation of pollen-pistil interaction. PMID:28250391

  17. Advances in understanding genomic markers and pharmacogenetics of Parkinson's disease.

    PubMed

    Jiménez-Jiménez, Félix Javier; Alonso-Navarro, Hortensia; García-Martín, Elena; Agúndez, José A G

    2016-01-01

    The inheritance pattern of Parkinson's disease (PD) is likely multifactorial (owing to the interplay of genetic predisposition and environmental factors). Many pharmacogenetic studies have tried to establish a possible role of candidate genes in PD risk. Several studies have focused on the influence of genes in the response to antiparkinsonian drugs and in the risk of developing side-effects of these drugs. This review presents an overview of current knowledge, with particular emphasis on the most recent advances, both in case-control association studies on the role of candidate genes in the risk for PD as well as pharmacogenetic studies on the role of genes in the development of side effects of antiparkinsonian drugs. The most reliable results should be derived from meta-analyses of case-control association studies on candidate genes involving large series of PD patients and controls, and from genome-wide association studies (GWAS). Prospective studies of large samples involving several genes with a detailed history of exposure to environmental factors in the same cohort of subjects, should be useful to clarify the role of genes in the risk for PD. The results of studies on the role of genes in the development of side-effects of antiparkinsonian drugs should, at this stage, only be considered preliminary.

  18. Advances in understanding and treating dystrophic epidermolysis bullosa

    PubMed Central

    Vanden Oever, Michael J

    2014-01-01

    Epidermolysis bullosa is a group of inherited disorders that can be both systemic and life-threatening. Standard treatments for the most severe forms of this disorder, typically limited to palliative care, are ineffective in reducing the morbidity and mortality due to complications of the disease. Emerging therapies—such as the use of allogeneic cellular therapy, gene therapy, and protein therapy—have all shown promise, but it is likely that several approaches will need to be combined to realize a cure. For recessive dystrophic epidermolysis bullosa, each particular therapeutic approach has added to our understanding of type VII collagen (C7) function and the basic biology surrounding the disease. The efficacy of these therapies and the mechanisms by which they function also give us insight into developing future strategies for treating this and other extracellular matrix disorders. PMID:24860657

  19. Recent advances in the pathological understanding of eosinophilic esophagitis.

    PubMed

    Cianferoni, Antonella; Spergel, Jonathan M; Muir, Amanda

    2015-01-01

    Eosinophilic esophagitis (EoE) is a chronic allergen-mediated inflammatory disease of the esophagus. This inflammation leads to feeding difficulties, failure to thrive and vomiting in young children, and causes food impaction and esophageal stricture in adolescents and adults. In the 20 years since EoE was first described, we have gained a great deal of knowledge regarding the genetic predisposition of disease, the inflammatory milieu associated with EoE and the long-term complications of chronic inflammation. Herein, we summarize the important breakthroughs in the field including both in vitro and in vivo analysis. We discuss insights that we have gained from large-scale unbiased genetic analysis, a multitude of genetically and chemically altered mouse models of EoE and most importantly, the results of clinical trials of various pharmacologic agents. Understanding these successes and failures may be the key to developing more effective therapeutic strategies.

  20. Recent Advances in Understanding and Managing Autism Spectrum Disorders

    PubMed Central

    Germain, Blair; Eppinger, Melissa A.; Mostofsky, Stewart H.; DiCicco-Bloom, Emanuel; Maria, Bernard L.

    2017-01-01

    Autism spectrum disorder in children is a group of neurodevelopmental disorders characterized by difficulties with social communication and behavior. Growing scientific evidence in addition to clinical practice has led the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to categorize several disorders into the broader category of autism spectrum disorder. As more is learned about how autism spectrum disorder manifests, progress has been made toward better clinical management including earlier diagnosis, care, and when specific interventions are required. The 2014 Neurobiology of Disease in Children symposium, held in conjunction with the 43rd annual meeting of the Child Neurology Society, aimed to (1) describe the clinical concerns involving diagnosis and treatment, (2) review the current status of understanding in the pathogenesis of autism spectrum disorder, (3) discuss clinical management and therapies for autism spectrum disorder, and (4) define future directions of research. The article summarizes the presentations and includes an edited transcript of question-and-answer sessions. PMID:26336201

  1. Recent Advances in Understanding and Managing Tourette Syndrome

    PubMed Central

    Thenganatt, Mary Ann; Jankovic, Joseph

    2016-01-01

    Tourette syndrome (TS) is a neurologic and behavioral disorder consisting of motor and phonic tics with onset in childhood or adolescence. The severity of tics can range from barely perceptible to severely impairing due to social embarrassment, discomfort, self-injury, and interference with daily functioning and school or work performance. In addition to tics, most patients with TS have a variety of behavioral comorbidities, including attention deficit hyperactivity disorder and obsessive-compulsive disorder. Studies evaluating the pathophysiology of tics have pointed towards dysfunction of the cortico-striato-thalamo-cortical circuit, but the mechanism of this hyperkinetic movement disorder is not well understood. Treatment of TS is multidisciplinary, typically involving behavioral therapy, oral medications, and botulinum toxin injections. Deep brain stimulation may be considered for “malignant” TS that is refractory to conventional therapy. In this review, we will highlight recent developments in the understanding and management strategies of TS. PMID:26918185

  2. Advances in the understanding, management, and prevention of dengue.

    PubMed

    Hermann, Laura L; Gupta, Swati B; Manoff, Susan B; Kalayanarooj, Siripen; Gibbons, Robert V; Coller, Beth-Ann G

    2015-03-01

    Dengue causes more human morbidity globally than any other vector-borne viral disease. Recent research has led to improved epidemiological methods that predict disease burden and factors involved in transmission, a better understanding of immune responses in infection, and enhanced animal models. In addition, a number of control measures, including preventative vaccines, are in clinical trials. However, significant gaps remain, including the need for better surveillance in large parts of the world, methods to predict which individuals will develop severe disease, and immunologic correlates of protection against dengue illness. During the next decade, dengue will likely expand its geographic reach and become an increasing burden on health resources in affected areas. Licensed vaccines and antiviral agents are needed in order to effectively control dengue and limit disease.

  3. Recent advances in understanding the endocrinology of human birth.

    PubMed

    Smith, Roger; Paul, Jonathan; Maiti, Kaushik; Tolosa, Jorge; Madsen, Gemma

    2012-10-01

    The timing of human birth has a crucial impact upon the survival of the fetus. New knowledge on the regulation of human birth includes the role of endogenous retroviruses in the formation of the syncytiotrophoblast cells and consequently the secretion of corticotrophin releasing hormone, a hormone linked to gestational length determination. miRNAs have been identified that mediate progesterone withdrawal at labor by suppressing progesterone-induced transcription factors. Progress has also been made in understanding how the contractile machinery of the uterine myocytes is activated at labor and the role of small heat-shock proteins in this process. From this work, new therapeutic targets have been identified that may be used to regulate the onset of labor and improve neonatal mortality. Copyright © 2012. Published by Elsevier Ltd.

  4. Recent advances in the understanding and management of rosacea

    PubMed Central

    2014-01-01

    Rosacea is a chronic relapsing inflammatory facial dermatosis. There are several known triggers but the pathogenesis remains unknown. Recent achievements in understanding this disease point to the importance of skin-environmental interactions. This includes physical and chemical factors, but also microbial factors. The impairment of the skin barrier function and the activation of the innate immune defences are major and connected pathways contributing to an ongoing inflammatory response in the affected skin. This becomes modulated by endogenous factors like neurovascular, drugs, and psychological factors. These factors offer new therapeutic targets for rosacea treatment. There is a broader range of anti-inflammatory compounds available with a favourable safety record. Only recently have persistent erythema and flushing been addressed by new drug formulations. PMID:25184040

  5. Recent Advancements in the Global Understanding of what Drives Heatwaves

    NASA Astrophysics Data System (ADS)

    Perkins-Kirkpatrick, S.

    2016-12-01

    Heatwaves, defined as prolonged periods of extreme heat, are disastrous events that impact human, natural and industrial systems all over the world. In recent years, the global research effort has greatly increased our understanding on quantifying heatwaves and how they have changed, what drives them, and their future projections. This talk will summarize critical developments made in this field, with particular emphasis on the physical driving mechanisms and the role of internal climate variability. Case studies from various global regions will illustrate both similarities and differences in the physical set-ups of these fascinating events. Future projections of heatwaves and the human contribution behind specific observed heatwave events will be briefly discussed. The talk will conclude by highlighting research priorities such that future investigation is targeted, and closes existing knowledge gaps on what drives heatwaves as effectively as possible. Such developments will ultimately aid in the predictability of heatwaves, thus aiding in reducing their devastating impacts.

  6. Recent Advances in Understanding Radiation Damage in Reactor Cavity Concrete

    SciTech Connect

    Rosseel, Thomas M; Field, Kevin G; Le Pape, Yann; Remec, Igor; Giorla, Alain B; Wall, Dr. James Joseph

    2015-01-01

    License renewal up to 60 years and the possibility of subsequent license renewal to 80 years has resulted in a renewed focus on long-term aging of materials at nuclear power plants (NPPs) including concrete. Large irreplaceable sections of most nuclear generating stations include concrete. The Expanded Materials Degradation Analysis, jointly performed by the Department of Energy, the Nuclear Regulatory Commission and Nuclear Industry, identified the urgent need to develop a consistent knowledge base on irradiation effects in concrete (Graves et al., (2014)). Much of the historical mechanical performance data of irradiated concrete (Hilsdorf et al., (1978)) does not accurately reflect typical radiation conditions in NPPs or conditions out to 60 or 80 years of radiation exposure (Kontani et al., (2011)). To address these potential gaps in the knowledge base, the Electric Power Research Institute and Oak Ridge National Laboratory, are working to better understand radiation damage as a degradation mechanism. This paper outlines recent progress toward: 1) assessing the radiation environment in concrete biological shields and defining the upper bound of the neutron and gamma dose levels expected in the biological shield for extended operation, and estimating adsorbed dose, 2) evaluating opportunities to harvest and test irradiated concrete from international NPPs, 3) evaluating opportunities to irradiate prototypical concrete and its components under accelerated neutron and gamma dose levels to establish conservative bounds and inform damage models, 4) developing improved models to enhance the understanding of the effects of radiation on concrete and 5) establishing an international collaborative research and information exchange effort to leverage capabilities and knowledge including developing cooperative test programs to improve confidence in data obtained from various concretes and from accelerated irradiation experiments.

  7. Understanding the Earth's Mantle Through Advanced Elasticity Measurements

    NASA Astrophysics Data System (ADS)

    Marquardt, Hauke; Schulze, Kirsten; Kurnosov, Alexander; Buchen, Johannes; Frost, Daniel; Boffa Ballaran, Tiziana; Marquardt, Katharina; Kawazoe, Takaaki

    2017-04-01

    Constraints on the inner structure, chemical and mineralogical composition as well as dynamics of Earth's mantle can be derived through comparison of laboratory elasticity data to seismological observables. A quantitative knowledge of the elastic properties of mantle minerals, and their variations with chemical composition, at pressure and temperature conditions of Earth's mantle is key to construct reliable synthetic mineral physics-based seismic velocity models to be compared to seismic observables. We will discuss results of single-crystal elasticity measurements on Earth mantle minerals that have been conducted using the combined Brillouin scattering and x-ray diffraction (XRD) system at BGI Bayreuth in combination with advanced sample preparation using the focused ion beam (FIB) technique [1] that allows for tailoring sizes and shapes of tiny single-crystals. In our experiments, multiple FIB-prepared single-crystals were loaded in a single sample chamber of a resistively-heated diamond-anvil cell (DAC). The possiblity to measure simultaneously acoustic wave velocities and density (unit-cell parameters) in the DAC in combination with the multi-sample approach facilitates direct quantification of the effects of chemical substitution on the elasticity and seismic wave velocities at non-ambient conditions. Our experimental approach eliminates uncertainties arising from the combination of data collected under (potentially) different conditions in several DAC runs, in different laboratories and/or from using different pressure-temperature sensors. We will present our recent experiments on the elasticity of single-crystal Fe-Al-bearing bridgmanite in the lower mantle and discuss implications for the composition and oxidation state of Earth's lower mantle. We will further discuss our laboratory data on the effects of 'water' and iron on the seismic wave velocities of ringwoodite in Earth's transition zone and outline implications for mapping 'water' in the transition

  8. Theoretical frameworks for understanding and investigating the therapeutic relationship in psychiatry.

    PubMed

    McGuire, R; McCabe, R; Priebe, S

    2001-11-01

    Mental health care is delivered through a relationship between a clinician and a patient. Although this therapeutic relationship is of central importance for mental health care, it appears to be relatively neglected in psychiatric research. Empirical research has for the most part adopted concepts and methods developed in psychotherapy and general medical practice. Hence, unpacking the presuppositions that have informed research on the therapeutic relationship to date may be a useful first step in developing this field. A review of the literature was carried out. Six central theories are identified as framing the definitions and methods on this topic: role theory, psychoanalysis, social constructionism, systems theory, social psychology and cognitive behaviourism. To date, role theory, psychoanalysis and systems theory appear to be the frameworks most often applied in research in this field. Each perspective offers a unique emphasis in the analysis of the therapeutic relationship, which is reflected in the empirical work from each perspective discussed herein. None of the theories identified have been fully specified and comprehensively investigated in psychiatric settings. However, more than one approach may be used for thinking about relationships, depending on the treatment situation. Further specification and testing of the theories in psychiatric practice--taking account of the specific context--is warranted to underpin more pragmatic research. A stronger link between fundamental psychological and sociological research and applied health care research would advance our understanding of which elements of positive therapeutic relationships are instrumental in improving patient outcome and ultimately contribute to improving mental health care.

  9. From evidence to understanding: a commentary on Fisher (1922) 'On the mathematical foundations of theoretical statistics'.

    PubMed

    Hand, David J

    2015-04-13

    The nature of statistics has changed over time. It was originally concerned with descriptive 'matters of state'--with summarizing population numbers, economic strength and social conditions. But during the course of the twentieth century its aim broadened to include inference--how to use data to shed light on underlying mechanisms, about what might happen in the future, about what would happen if certain actions were taken. Central to this development was Ronald Fisher. Over the course of his life he was responsible for many of the major conceptual advances in statistics. This is particularly illustrated by his 1922 paper, in which he introduced many of the concepts which remain fundamental to our understanding of how to extract meaning from data, right to the present day. It is no exaggeration to say that Fisher's work, as illustrated by the ideas he described and developed in this paper, underlies all modern science, and much more besides. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

  10. Advances in understanding etiology of achondroplasia and review of management.

    PubMed

    Carter, Erin M; Davis, Jessica G; Raggio, Cathleen L

    2007-02-01

    A summary of management and current research in achondroplasia (OMIM 100800). The most common nonlethal skeletal dysplasia, achondroplasia presents a distinct clinical picture evident at birth. Substantial information is available concerning the natural history of this dwarfing disorder. Diagnosis is made by clinical findings and radiographic features. Characteristic features include short limbs, a relatively large head with frontal bossing and midface hypoplasia, trident hands, muscular hypotonia, and thoracolumbar kyphosis. Children commonly have recurrent ear infections, delayed motor milestones, and eventually develop bowed legs and lumbar lordosis. People with achondroplasia are generally of normal intelligence. The genetic cause of achondroplasia was discovered in 1994. Subsequent research efforts are designed to better characterize the underlying possible biochemical mechanisms responsible for the clinical findings of achondroplasia as well as to develop possible new therapies and/or improve intervention. Establishing a diagnosis of achondroplasia allows families and clinicians to provide anticipatory care for affected children. Although the primary features of achondroplasia affect the skeleton, a multidisciplinary approach to care for children with achondroplasia helps families and clinicians understand the clinical findings and the natural history of achondroplasia in order to improve the outcome for each patient.

  11. Recent advances in understanding physical properties of metallurgical slags

    NASA Astrophysics Data System (ADS)

    Min, Dong Joon; Tsukihashi, Fumitaka

    2017-01-01

    Present-day knowledge of the structure and physical properties of metallurgical slags is summarized to address structure-property and inter-property relationships. Physical properties of slags including viscosity, electrical conductivity, and surface tension is reviewed focusing on the effect of slag structure, which is comprehensively evaluated using FT-IT, Raman, and MAS-NMR spectroscopy. The effect of the slag composition on slag structure and property is reviewed in detail: Compositional effect encompasses traditional concepts of basicity, network-forming behaviors of anions, and secondary impact of network-modifying cations. Secondary objective of this review is elucidating the mutual relationship between physical properties of slags. For instance, the relationship between slag viscosity and electrical conductivity is suggested by Walden's rule and discussed based on the experimental results. Slag foaming index is also introduced as a comprehensive understanding method of physical properties of slags. The dimensional analysis was made to address the effect of viscosity, density, and surface tension on the foaming index of slags.

  12. Understanding of Mechanisms for Design of Advanced Superconductors

    NASA Astrophysics Data System (ADS)

    Pickett, Warren

    2007-03-01

    A recent DOE panel considered the future of research in superconducting materials and made a number of recommendations for priority research directions (http://www.er.doe.gov/bes/reports/files/SCrpt.pdf), two of which will be discussed. These items, under the rubric of Enabling Superconductivity, emphasize that Finding the Mechanisms is essential for furthering the field, and that once understood, the prospect of Superconductors by Design becomes a viable line of research. Establishing the mechanism in the high temperature superconducting cuprates continues to attract substantial efforts, with no consensus near. In several superconductors, including some discovered in the past decade or so, having Tc around or above 20 K [(Ba,K)BiO3; LixHfNCl; PuCoGa5] the mechanism is in question. On the more positive side, there are several cases established in the past six years, beginning with MgB2 and extending to elemental metals under pressure (Li, Y, Ca), where the familiar electron-phonon mechanism has provided unexpectedly high Tc and thereby stimulated enthusiasm and optimism into this area of superconductivity research. The clear understanding of this mechanism (at least in many respects) provides a path for improvements in superconducting materials.

  13. Recent advances in understanding ice sheet dynamics [rapid communication

    NASA Astrophysics Data System (ADS)

    Marshall, Shawn J.

    2005-12-01

    Glaciers and ice sheets play a dynamic role in Earth's climate system, influencing regional- and global-scale climate and responding to climate change on time scales from years to millennia. They are also an integral part of Earth's landscape in alpine and polar regions, where they are an active agent in isostatic, tectonic, and Earth surface processes. This review paper summarizes recent progress in understanding and modelling ice sheet dynamics, from the microphysical processes of ice deformation in glaciers to continental-scale processes that influence ice dynamics. Based on recent insights and research directions, it can be expected that a new generation of ice sheet models will soon replace the current standard. Improvements that can be foreseen in the near future include: (i) the addition of internally-consistent evolutionary equations for ice crystal fabric (anisotropic flow laws), (ii) more generalized flow laws that include different deformation mechanisms under different stress regimes, (iii) explicit incorporation of the effects of chemical impurities and grain size (dynamic recrystallization) on ice deformation, (iv) higher-order stress solutions to the momentum balance (Stokes' equation) that governs ice sheet flow, and (v) the continued merger of ice sheet models with increasingly complex Earth systems models, which include fully-coupled subglacial hydrological and geological processes. Examples from the Greenland Ice Sheet and Vatnajökull Ice Cap, Iceland are used to illustrate several of these new directions and their importance to glacier dynamics.

  14. [Acute pancreatitis: recent advances in understanding its pathophysiology].

    PubMed

    Telek, G; Fehér, J; Jakab, F; Claude, R

    2000-02-06

    This article reviews the recent changes in the understanding of acute pancreatitis pathophysiology emphasizing results deriving from the more detailed comprehension of the local and systemic aspects of the inflammatory process. The authors briefly discuss those theories that have been influencing the basic philosophies of treatment efforts. The role of premature digestive enzyme activation as the principal determinant of the pathoetiology and mortality of this disease has been questioned lately, and the inflammatory explosion has been placed into the center of attention. Simultaneously with the enzyme activation, the pancreatitogenic noxious event rapidly induces the formation of oxygen derived free radicals, activation of the transcription factor NF kappa-B, with consequent citokine production, cellular adhesion molecule upregulation and leukocyte hyperstimulation. Numerous other mediator cascades are activated in parallel, the uncontrolled surge of proinflammatory stimuli, and activity of the effector cells lead to multiple organ failure in severe cases. A genetically determined catastrophe management program is set forth in the acinar cell with pancreatitis associated protein expression and activation of the apoptosis machinery. Therapeutic approaches based on these recent findings are briefly touched upon.

  15. Advances in the molecular understanding of gonadotropins-receptors interactions.

    PubMed

    el Tayar, N

    1996-12-20

    The extracellular domain (ECD) of gonadotropin receptors belong to the leucine-rich repeat (LRR) protein superfamily and their transmembrane domain (TMD) is characteristic of the seven alpha-helices G-protein-coupled receptors (GPCR). The availability of the X-ray structures of porcine ribonuclease inhibitor (RI), a LRR protein, and bacteriorhodopsin (bR) allows the construction of 3D models of the ECD and the TMD of gonadotropin receptors, respectively. The predicted models are to a large extent consistent with currently available biochemical and mutational data. The models provide a reliable basis for understanding how the hormone binds and activates its receptor. The ECD, in particular the LRR region, serves as a baseball glove which efficiently catches the large hormone and optimally orient the appropriate parts of it for interaction with the seven-transmembrane-helix domain of the receptor. This in turn is expected to lead to a conformational change to be sensed by the appropriate G-protein complex leading to the stimulation of cAMP synthesis and steroids production.

  16. Sharing methodology: a worked example of theoretical integration with qualitative data to clarify practical understanding of learning and generate new theoretical development.

    PubMed

    Yardley, Sarah; Brosnan, Caragh; Richardson, Jane

    2013-01-01

    Theoretical integration is a necessary element of study design if clarification of experiential learning is to be achieved. There are few published examples demonstrating how this can be achieved. This methodological article provides a worked example of research methodology that achieved clarification of authentic early experiences (AEEs) through a bi-directional approach to theory and data. Bi-directional refers to our simultaneous use of theory to guide and interrogate empirical data and the use of empirical data to refine theory. We explain the five steps of our methodological approach: (1) understanding the context; (2) critique on existing applications of socio-cultural models to inform study design; (3) data generation; (4) analysis and interpretation and (5) theoretical development through a novel application of Metis. These steps resulted in understanding of how and why different outcomes arose from students participating in AEE. Our approach offers a mechanism for clarification without which evidence-based effective ways to maximise constructive learning cannot be developed. In our example it also contributed to greater theoretical understanding of the influence of social interactions. By sharing this example of research undertaken to develop both theory and educational practice we hope to assist others seeking to conduct similar research.

  17. Reef sharks: recent advances in ecological understanding to inform conservation.

    PubMed

    Osgood, G J; Baum, J K

    2015-12-01

    Sharks are increasingly being recognized as important members of coral-reef communities, but their overall conservation status remains uncertain. Nine of the 29 reef-shark species are designated as data deficient in the IUCN Red List, and three-fourths of reef sharks had unknown population trends at the time of their assessment. Fortunately, reef-shark research is on the rise. This new body of research demonstrates reef sharks' high site restriction, fidelity and residency on coral reefs, their broad trophic roles connecting reef communities and their high population genetic structure, all information that should be useful for their management and conservation. Importantly, recent studies on the abundance and population trends of the three classic carcharhinid reef sharks (grey reef shark Carcharhinus amblyrhynchos, blacktip reef shark Carcharhinus melanopterus and whitetip reef shark Triaenodon obesus) may contribute to reassessments identifying them as more vulnerable than currently realized. Because over half of the research effort has focused on only these three reef sharks and the nurse shark Ginglymostoma cirratum in only a few locales, there remain large taxonomic and geographic gaps in reef-shark knowledge. As such, a large portion of reef-shark biodiversity remains uncharacterized despite needs for targeted research identified in their red list assessments. A research agenda for the future should integrate abundance, life history, trophic ecology, genetics, habitat use and movement studies, and expand the breadth of such research to understudied species and localities, in order to better understand the conservation requirements of these species and to motivate effective conservation solutions.

  18. Advances in understanding and utilising ELM control in JET

    NASA Astrophysics Data System (ADS)

    Chapman, I. T.; de la Luna, E.; Lang, P. T.; Liang, Y.; Alper, B.; Denner, P.; Frigione, D.; Garzotti, L.; Ham, C. J.; Huijsmans, G. T. A.; Jachmich, S.; Kocsis, G.; Lennholm, M.; Lupelli, I.; Rimini, F. G.; Sips, A. C. C.; Contributors, JET

    2016-01-01

    Edge localised mode (ELM) control may be essential to develop ITER scenarios with a reasonable lifetime of divertor components, whilst ELM pacing may be essential to develop stationary ITER scenarios with a tungsten divertor. Resonant magnetic perturbations (RMPs) have mitigated ELMs in high collisionality plasmas in JET. The efficacy of RMPs in mitigating the ELMs is found to depend on plasma shaping, with the change in magnetic boundary achieved when non-axisymmetric fields are applied facilitating access to small ELM regimes. The understanding of ELM pacing by vertical kicks or pellets has also been improved in a range of pedestal conditions in JET ({{T}\\text{ped}}=0.7 -1.3 keV) encompassing the ITER-expected domain ({β\\text{N}}=1.4 -2.4, H 98(y, 2)  =  0.8-1.2, {{f}\\text{GW}}˜ 0.7 ). ELM triggering is reliable provided the perturbation is above a threshold which depends on pedestal parameters. ELM triggering is achieved even in the first 10% of the natural ELM cycle suggesting no inherent maximum frequency. At high normalised pressure, the peeling-ballooning modes are stabilised as predicted by ELITE, necessitating a larger perturbation from either kicks or pellets in order to trigger ELMs. Both kicks and pellets have been used to pace ELMs for tungsten flushing. This has allowed stationary plasma conditions with low gas injection in plasmas where the natural ELM frequency is such that it would normally preclude stationary conditions.

  19. Beyond vascular inflammation--recent advances in understanding atherosclerosis.

    PubMed

    Wolf, Dennis; Zirlik, Andreas; Ley, Klaus

    2015-10-01

    Atherosclerosis is the most life-threatening pathology worldwide. Its major clinical complications, stroke, myocardial infarction, and heart failure, are on the rise in many regions of the world--despite considerable progress in understanding cause, progression, and consequences of atherosclerosis. Originally perceived as a lipid-storage disease of the arterial wall (Die cellularpathologie in ihrer begründung auf physiologische und pathologische gewebelehre. August Hirschwald Verlag Berlin, [1871]), atherosclerosis was recognized as a chronic inflammatory disease in 1986 (New Engl J Med 314:488-500, 1986). The presence of lymphocytes in atherosclerotic lesions suggested autoimmune processes in the vessel wall (Clin Exp Immunol 64:261-268, 1986). Since the advent of suitable mouse models of atherosclerosis (Science 258:468-471, 1992; Cell 71:343-353, 1992; J Clin Invest 92:883-893, 1993) and the development of flow cytometry to define the cellular infiltrate in atherosclerotic lesions (J Exp Med 203:1273-1282, 2006), the origin, lineage, phenotype, and function of distinct inflammatory cells that trigger or inhibit the inflammatory response in the atherosclerotic plaque have been studied. Multiphoton microscopy recently enabled direct visualization of antigen-specific interactions between T cells and antigen-presenting cells in the vessel wall (J Clin Invest 122:3114-3126, 2012). Vascular immunology is now emerging as a new field, providing evidence for protective as well as damaging autoimmune responses (Int Immunol 25:615-622, 2013). Manipulating inflammation and autoimmunity both hold promise for new therapeutic strategies in cardiovascular disease. Ongoing work (J Clin Invest 123:27-36, 2013; Front Immunol 2013; Semin Immunol 31:95-101, 2009) suggests that it may be possible to develop antigen-specific immunomodulatory prevention and therapy-a vaccine against atherosclerosis.

  20. Polarization propagators: A powerful theoretical tool for a deeper understanding of NMR spectroscopic parameters

    NASA Astrophysics Data System (ADS)

    Aucar, Gustavo A.; Romero, Rodolfo H.; Maldonado, Alejandro F.

    Magnetic molecular spectroscopic properties, like NMR J-coupling and magnetic shielding σ, have been studied by non-relativistic quantum methods since their discovery. When they were found to depend strongly on relativistic effects in molecules containing heavy atoms, this started a new area of intensive research into the development of methods that include such effects. In most cases non-relativistic concepts were extended to the new field though keeping the previous non-relativistic point of view. Quantum mechanics can be formulated by two different formal approaches. Molecular physics and quantum chemistry were developed mostly within the Schrödinger or Heisenberg approaches. The path integral formalism of Feynman is less well known. This may be the reason why propagators are not broadly known in this field of research. Polarization propagators were developed in the early 1970s. Since that time they have been successfully applied to calculate NMR spectroscopic parameters. They are special theoretical devices from which one can do a deep analysis of the electronic mechanisms that underly any molecular response property from basic theoretical elements, like molecular orbitals, electronic excitation energies, coupling pathways, entanglement, contributions within different levels of theory, etc. All this is obtained in a natural way in both regimes: relativistic and non-relativistic. Its relativistic generalization in the early 1990s and the finding of a quantum electrodynamic (QED)-based theory for them, has given us the opportunity to improve our understanding of the physics behind such parameters. In this paper we give a presentation of polarization propagators that start in non-relativistic quantum physics and end up with the introduction of QED effects. The same and powerful basic quantum ideas are applied throughout this review, so that coherence and beauty arise in a natural way. We will give a new understanding that comes from the three levels of theory

  1. A Changing Landscape of Advanced Prostate Cancer: Understanding Mechanisms of Resistance to Potent Hormonal Therapies

    DTIC Science & Technology

    2015-10-01

    1 AWARD NUMBER: W81XWH-13-1-0275 TITLE: A Changing Landscape of Advanced Prostate Cancer: Understanding Mechanisms of Resistance to Potent...TYPE Annual 3. DATES COVERED 30 Sep 2014 - 29 Sep 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER A Changing Landscape of Advanced Prostate Cancer...not curative, and all patients ultimately develop resistance. Therefore, the clinical and molecular landscape of advanced prostate cancer is changing

  2. Recent Advances in Understanding the Role of Nutrition in Human Genome Evolution12

    PubMed Central

    Ye, Kaixiong; Gu, Zhenglong

    2011-01-01

    Dietary transitions in human history have been suggested to play important roles in the evolution of mankind. Genetic variations caused by adaptation to diet during human evolution could have important health consequences in current society. The advance of sequencing technologies and the rapid accumulation of genome information provide an unprecedented opportunity to comprehensively characterize genetic variations in human populations and unravel the genetic basis of human evolution. Series of selection detection methods, based on various theoretical models and exploiting different aspects of selection signatures, have been developed. Their applications at the species and population levels have respectively led to the identification of human specific selection events that distinguish human from nonhuman primates and local adaptation events that contribute to human diversity. Scrutiny of candidate genes has revealed paradigms of adaptations to specific nutritional components and genome-wide selection scans have verified the prevalence of diet-related selection events and provided many more candidates awaiting further investigation. Understanding the role of diet in human evolution is fundamental for the development of evidence-based, genome-informed nutritional practices in the era of personal genomics. PMID:22332091

  3. Recent theoretical advances in analysis of AIRS/AMSU sounding data

    NASA Astrophysics Data System (ADS)

    Susskind, Joel

    2007-04-01

    The AIRS Science Team Version 5.0 retrieval algorithm will become operational at the Goddard DAAC in early 2007 in the near real-time analysis of AIRS/AMSU sounding data. This algorithm contains many significant theoretical advances over the AIRS Science Team Version 4.0 retrieval algorithm used previously. Three very significant developments are: 1) the development and implementation of a very accurate Radiative Transfer Algorithm (RTA) which allows for accurate treatment of non-Local Thermodynamic Equilibrium (non-LTE) effects on shortwave sounding channels; 2) the development of methodology to obtain very accurate case by case product error estimates which are in turn used for quality control; and 3) development of an accurate AIRS only cloud clearing and retrieval system. These theoretical improvements taken together enabled a new methodology to be developed which further improves soundings in partially cloudy conditions, without the need for microwave observations in the cloud clearing step as has been done previously. In this methodology, longwave CO II channel observations in the spectral region 700 cm -1 to 750 cm -1 are used exclusively for cloud clearing purposes, while shortwave CO II channels in the spectral region 2195 cm -1 to 2395 cm -1 are used for temperature sounding purposes. The new methodology is described briefly and results are shown, including comparison with those using AIRS Version 4, as well as a forecast impact experiment assimilating AIRS Version 5.0 retrieval products in the Goddard GEOS 5 Data Assimilation System.

  4. What I Wish: Three Advancement Professionals Discuss What Their Colleagues Need to Understand about Their Jobs

    ERIC Educational Resources Information Center

    Gurd, Andy; Peirce, Susan; Morris, Sarah

    2012-01-01

    Three advancement professionals discuss what their colleagues need to understand about their jobs. The Ohio State University Alumni Association is currently integrating into the university's advancement office at the behest of the board of trustees, so Andy Gurd is now working more closely with his development and communications colleagues than…

  5. What I Wish: Three Advancement Professionals Discuss What Their Colleagues Need to Understand about Their Jobs

    ERIC Educational Resources Information Center

    Gurd, Andy; Peirce, Susan; Morris, Sarah

    2012-01-01

    Three advancement professionals discuss what their colleagues need to understand about their jobs. The Ohio State University Alumni Association is currently integrating into the university's advancement office at the behest of the board of trustees, so Andy Gurd is now working more closely with his development and communications colleagues than…

  6. The Promoting Effective Advance Care for Elders (PEACE) randomized pilot study: theoretical framework and study design.

    PubMed

    Allen, Kyle R; Hazelett, Susan E; Radwany, Steven; Ertle, Denise; Fosnight, Susan M; Moore, Pamela S

    2012-04-01

    Practice guidelines are available for hospice and palliative medicine specialists and geriatricians. However, these guidelines do not adequately address the needs of patients who straddle the 2 specialties: homebound chronically ill patients. The purpose of this article is to describe the theoretical basis for the Promoting Effective Advance Care for Elders (PEACE) randomized pilot study. PEACE is an ongoing 2-group randomized pilot study (n=80) to test an in-home interdisciplinary care management intervention that combines palliative care approaches to symptom management, psychosocial and emotional support, and advance care planning with geriatric medicine approaches to optimizing function and addressing polypharmacy. The population comprises new enrollees into PASSPORT, Ohio's community-based, long-term care Medicaid waiver program. All PASSPORT enrollees have geriatric/palliative care crossover needs because they are nursing home eligible. The intervention is based on Wagner's Chronic Care Model and includes comprehensive interdisciplinary care management for these low-income frail elders with chronic illnesses, uses evidence-based protocols, emphasizes patient activation, and integrates with community-based long-term care and other community agencies. Our model, with its standardized, evidence-based medical and psychosocial intervention protocols, will transport easily to other sites that are interested in optimizing outcomes for community-based, chronically ill older adults. © Mary Ann Liebert, Inc.

  7. Primary healthcare NZ nurses' experiences of advance directives: understanding their potential role.

    PubMed

    Davidson, Raewyn; Banister, Elizabeth; de Vries, Kay

    2013-07-01

    Advance directives are one aspect of advance care planning designed to improve end of life care. The New Zealand Nurses Organisation released their first mission statement in 2010 concerning advance directives suggesting an increase in the use of these. A burgeoning older population, expected to rise over the next few years, places the primary healthcare nurse in a pivotal role to address the challenges in constructing advance directives. While literature supports the role for primary healthcare nurses in promoting advance directives, no research was found on this role in the New Zealand context. This paper presents results of a qualitative study conducted in New Zealand with 13 senior primary healthcare nurses with respect to their knowledge, attitudes, and experiences of advance directives. Results of the analysis revealed a dynamic process involving participants coming to understand their potential role in this area. This process included reflection on personal experience with advance directives; values and ethics related to end of life issues; and professional actions.

  8. BOOK REVIEW: New Understanding Physics for Advanced Level

    NASA Astrophysics Data System (ADS)

    Breithaupt, Jim

    2000-09-01

    Breithaupt's new book is big: at 727 pages, it will be a hefty addition to any student's bag. According to the preface, the book is designed to help students achieve the transition from GCSE to A-level and to succeed well at this level. It also aims to cover the requirements of the compulsory parts of all new syllabuses and to cover most of the optional material, too. The book is organized into seven themes along traditional lines: mechanics, materials, fields, waves, electricity, inside the atom, and physics in medicine. Each theme begins with a colourful title page that outlines what the theme is about, lists the applications that students will meet in their reading, identifies prior learning from GCSE and gives a checklist of what students should be able to do once they have finished their reading of the theme. This is all very useful. The text of the book is illustrated with many colourful photographs, pictures and cartoons, but despite this it looks very dense. There are a lot of words on every page in a small font that makes them seem very unfriendly, and although the book claims to be readable I rather doubt that the layout will encourage voluntary reading of the text. Each chapter ends with a useful summary and a selection of short questions that allow students to test their understanding. Each theme has a set of multiple choice and long questions. Some of the questions have an icon referring the student to the accompanying CD (more of this later). There is much up-to-date material in the book. For example, the section on cosmology gives a brief description of the inflationary scenario within the Big Bang model of the origin of the universe, although no mechanism for the inflation is given, which might prove unsatisfying to some students. I do have some reservations about the presentation of some topics within the book: the discussion of relativistic mass, for example, states that `Einstein showed that the mass ... is given by the formula ...' and quotes

  9. Towards a Theoretical Framework for Understanding PGCE Student Teacher Learning in the Wild Coast Rural Schools' Partnership Project

    ERIC Educational Resources Information Center

    Pennefather, Jane

    2016-01-01

    This article focuses on a theoretical model that I am developing in order to understand student teacher learning in a rural context and the enabling conditions that can support this learning. The question of whether a supervised teaching practice in a rural context can contribute to the development of student teacher professional learning and…

  10. Towards a Theoretical Framework for Understanding PGCE Student Teacher Learning in the Wild Coast Rural Schools' Partnership Project

    ERIC Educational Resources Information Center

    Pennefather, Jane

    2016-01-01

    This article focuses on a theoretical model that I am developing in order to understand student teacher learning in a rural context and the enabling conditions that can support this learning. The question of whether a supervised teaching practice in a rural context can contribute to the development of student teacher professional learning and…

  11. Revealing membrane potential by advanced impedance spectroscopy: theoretical and experimental aspects

    NASA Astrophysics Data System (ADS)

    Gheorghiu, M.; Bratu, D.; Olaru, A.; Polonschii, C.; Gheorghiu, E.

    2013-04-01

    In spite of recent advancement of novel optical and electrical techniques, availability of non-invasive, label-free methods to assess membrane potential of living cells is still an open issue. The theory linking membrane potential to the low frequency α dispersion exhibited by suspensions of spherical shelled particles (presenting a net charge distribution on the inner side of the shell) has been pioneered in our previous studies with emphasis on the permittivity spectra. We now report on both theoretical and experimental aspects showing that whereas α dispersion is related to a rather large variation exhibited by the permittivity spectrum the decrement presented by impedance magnitude spectrum is either extremely small, or occurs (for large cells) at very low frequencies (~mHz) explaining the lack of experimental bioimpedance data on the matter. Based on the microscopic model we indicate that an appropriate design of the experiment may enable access to membrane potential as well as to other relevant parameters when investigating living cells and charged lipid vesicles. We discuss the effect on the low frequency of permittivity and impedance spectra of: I. Parameters pertaining to cell membrane i.e. (i) membrane potential, (ii) size of the cells/vesicles, (iii) conductivity; II. Conductivity of the outer medium. A novel measuring set-up has recently been developed within the International Centre of Biodynamics allowing for sensitive low frequency (~10mHz) four point (bio)impedance assays. Its capability to test theoretical predictions is reported as well. The far reaching implications of this study applicability for life sciences (noninvasive access to the dynamics of relevant cell parameters) as well as for biosensing applications, e.g. assess the cytotoxicity of a wide range of stimuli, will be outlined.

  12. Assessing Students' Understandings of Biological Models and Their Use in Science to Evaluate a Theoretical Framework

    ERIC Educational Resources Information Center

    Grünkorn, Juliane; Upmeier zu Belzen, Annette; Krüger, Dirk

    2014-01-01

    Research in the field of students' understandings of models and their use in science describes different frameworks concerning these understandings. Currently, there is no conjoint framework that combines these structures and so far, no investigation has focused on whether it reflects students' understandings sufficiently (empirical evaluation).…

  13. Assessing Students' Understandings of Biological Models and Their Use in Science to Evaluate a Theoretical Framework

    ERIC Educational Resources Information Center

    Grünkorn, Juliane; Upmeier zu Belzen, Annette; Krüger, Dirk

    2014-01-01

    Research in the field of students' understandings of models and their use in science describes different frameworks concerning these understandings. Currently, there is no conjoint framework that combines these structures and so far, no investigation has focused on whether it reflects students' understandings sufficiently (empirical evaluation).…

  14. Theoretical and Experimental Studies of the Electro-Optic Effect: Toward a Microscopic Understanding.

    DTIC Science & Technology

    1981-08-01

    The electro - optic effect is investigated both theoretically and experimentally. The theoretical approach is based upon W.A. Harrison’s ’Bond-Orbital...Model’. The separate electronic and lattice contributions to the second-order, electro - optic susceptibility are examined within the context of this...frequency (dc) electric field is outlined. Finally, experimental measurements of the electro - optic effects in TeO2 and tl3AsAs3 have been performed and the results of these measurements are presented. (Author)

  15. EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF NEW POWER CYCLES AND ADVANCED FALLING FILM HEAT EXCHANGERS

    SciTech Connect

    Arsalan Razani; Kwang J. Kim

    2001-12-01

    The final report for the DOE/UNM grant number DE-FG26-98FT40148 discusses the accomplishments of both the theoretical analysis of advanced power cycles and experimental investigation of advanced falling film heat exchangers. This final report also includes the progress report for the third year (period of October 1, 2000 to September 30, 2001). Four new cycles were studied and two cycles were analyzed in detail based on the second law of thermodynamics. The first cycle uses a triple combined cycle, which consists of a topping cycle (Brayton/gas), an intermediate cycle (Rankine/steam), and a bottoming cycle (Rankine/ammonia). This cycle can produce high efficiency and reduces the irreversibility of the Heat Recovery Steam Generator (HRSC) of conventional combined power cycles. The effect of important system parameters on the irreversibility distribution of all components in the cycle under reasonable practical constraints was evaluated. The second cycle is a combined cycle, which consists of a topping cycle (Brayton/gas) and a bottoming cycle (Rankine/ammonia) with integrated compressor inlet air cooling. This innovative cycle can produce high power and efficiency. This cycle is also analyzed and optimized based on the second the second law to obtain the irreversibility distribution of all components in the cycle. The results of the studies have been published in peer reviewed journals and ASME conference proceeding. Experimental investigation of advanced falling film heat exchangers was conducted to find effective additives for steam condensation. Four additives have been selected and tested in a horizontal tube steam condensation facility. It has been observed that heat transfer additives have been shown to be an effective way to increase the efficiency of conventional tube bundle condenser heat exchangers. This increased condensation rate is due to the creation of a disturbance in the liquid condensate surround the film. The heat transfer through such a film has

  16. Exploring Asynchrony as a Theoretical Framework for Understanding Giftedness: A Case of Cognitive Dissonance?

    ERIC Educational Resources Information Center

    Andronaco, Julie A.; Shute, Rosalyn; McLachlan, Angus

    2014-01-01

    Asynchrony is a theoretical construct that views the intellectually gifted child as inherently vulnerable because of disparities arising from the mismatch between his or her chronological age and mental age. Such disparities, for example, between wanting to belong but being intellectually out of step with peers, are said to give rise to a…

  17. Understanding Older Adults' Physical Activity Behavior: A Multi-Theoretical Approach

    ERIC Educational Resources Information Center

    Grodesky, Janene M.; Kosma, Maria; Solmon, Melinda A.

    2006-01-01

    Physical inactivity is a health issue with serious consequences for older adults. Investigating physical activity promotion within a multi-theoretical approach may increase the predictive strength of physical activity determinants and facilitate the development and implementation of effective interventions for older adults. This article examines…

  18. Understanding, Selecting, and Integrating a Theoretical Framework in Dissertation Research: Creating the Blueprint for Your "House"

    ERIC Educational Resources Information Center

    Grant, Cynthia; Osanloo, Azadeh

    2014-01-01

    The theoretical framework is one of the most important aspects in the research process, yet is often misunderstood by doctoral candidates as they prepare their dissertation research study. The importance of theory-driven thinking and acting is emphasized in relation to the selection of a topic, the development of research questions, the…

  19. Understanding Older Adults' Physical Activity Behavior: A Multi-Theoretical Approach

    ERIC Educational Resources Information Center

    Grodesky, Janene M.; Kosma, Maria; Solmon, Melinda A.

    2006-01-01

    Physical inactivity is a health issue with serious consequences for older adults. Investigating physical activity promotion within a multi-theoretical approach may increase the predictive strength of physical activity determinants and facilitate the development and implementation of effective interventions for older adults. This article examines…

  20. First-Year Biology Students' Understandings of Meiosis: An Investigation Using a Structural Theoretical Framework

    ERIC Educational Resources Information Center

    Quinn, Frances; Pegg, John; Panizzon, Debra

    2009-01-01

    Meiosis is a biological concept that is both complex and important for students to learn. This study aims to explore first-year biology students' explanations of the process of meiosis, using an explicit theoretical framework provided by the Structure of the Observed Learning Outcome (SOLO) model. The research was based on responses of 334…

  1. Exploring Asynchrony as a Theoretical Framework for Understanding Giftedness: A Case of Cognitive Dissonance?

    ERIC Educational Resources Information Center

    Andronaco, Julie A.; Shute, Rosalyn; McLachlan, Angus

    2014-01-01

    Asynchrony is a theoretical construct that views the intellectually gifted child as inherently vulnerable because of disparities arising from the mismatch between his or her chronological age and mental age. Such disparities, for example, between wanting to belong but being intellectually out of step with peers, are said to give rise to a…

  2. Understanding the Role of Numeracy in Health: Proposed Theoretical Framework and Practical Insights

    ERIC Educational Resources Information Center

    Lipkus, Isaac M.; Peters, Ellen

    2009-01-01

    Numeracy--that is, how facile people are with mathematical concepts and their applications--is gaining importance in medical decision making and risk communication. This article proposes six critical functions of health numeracy. These functions are integrated into a theoretical framework on health numeracy that has implications for risk…

  3. Understanding the Role of Numeracy in Health: Proposed Theoretical Framework and Practical Insights

    ERIC Educational Resources Information Center

    Lipkus, Isaac M.; Peters, Ellen

    2009-01-01

    Numeracy--that is, how facile people are with mathematical concepts and their applications--is gaining importance in medical decision making and risk communication. This article proposes six critical functions of health numeracy. These functions are integrated into a theoretical framework on health numeracy that has implications for risk…

  4. First-Year Biology Students' Understandings of Meiosis: An Investigation Using a Structural Theoretical Framework

    ERIC Educational Resources Information Center

    Quinn, Frances; Pegg, John; Panizzon, Debra

    2009-01-01

    Meiosis is a biological concept that is both complex and important for students to learn. This study aims to explore first-year biology students' explanations of the process of meiosis, using an explicit theoretical framework provided by the Structure of the Observed Learning Outcome (SOLO) model. The research was based on responses of 334…

  5. Designerly Ways to Theoretical Insight: Visualisation as a Means to Explore, Discuss and Understand Design Theory

    ERIC Educational Resources Information Center

    Bang, Anne Louise; Friis, Silje Alberthe Kamille; Gelting, Anne Katrine Gøtzsche

    2015-01-01

    This paper set out to investigate "how design students learn from visualising theory in design education." The exploration rests on the assumption that the application of tools and techniques from design practice supports design students with an entrance to the theoretical part of the field. The paper is based on teaching experiences…

  6. ENHANCING THE ATOMIC-LEVEL UNDERSTANDING OF CO2 MINERAL SEQUESTRATION MECHANISMS VIA ADVANCED COMPUTATIONAL MODELING

    SciTech Connect

    A.V.G. Chizmeshya; M.J. McKelvy; G.H. Wolf; R.W. Carpenter; D.A. Gormley; J.R. Diefenbacher; R. Marzke

    2006-03-01

    significantly improved our understanding of mineral carbonation. Group members at the Albany Research Center have recently shown that carbonation of olivine and serpentine, which naturally occurs over geological time (i.e., 100,000s of years), can be accelerated to near completion in hours. Further process refinement will require a synergetic science/engineering approach that emphasizes simultaneous investigation of both thermodynamic processes and the detailed microscopic, atomic-level mechanisms that govern carbonation kinetics. Our previously funded Phase I Innovative Concepts project demonstrated the value of advanced quantum-mechanical modeling as a complementary tool in bridging important gaps in our understanding of the atomic/molecular structure and reaction mechanisms that govern CO2 mineral sequestration reaction processes for the model Mg-rich lamellar hydroxide feedstock material Mg(OH)2. In the present simulation project, improved techniques and more efficient computational schemes have allowed us to expand and augment these capabilities and explore more complex Mg-rich, lamellar hydroxide-based feedstock materials, including the serpentine-based minerals. These feedstock materials are being actively investigated due to their wide availability, and low-cost CO2 mineral sequestration potential. Cutting-edge first principles quantum chemical, computational solid-state and materials simulation methodology studies proposed herein, have been strategically integrated with our new DOE supported (ASU-Argonne National Laboratory) project to investigate the mechanisms that govern mineral feedstock heat-treatment and aqueous/fluid-phase serpentine mineral carbonation in situ. This unified, synergetic theoretical and experimental approach has provided a deeper understanding of the key reaction mechanisms than either individual approach can alone. We used ab initio techniques to significantly advance our understanding of atomic-level processes at the solid/solution interface by

  7. ENHANCING THE ATOMIC-LEVEL UNDERSTANDING OF CO2 MINERAL SEQUESTRATION MECHANISMS VIA ADVANCED COMPUTATIONAL MODELING

    SciTech Connect

    A.V.G. Chizmeshya

    2003-12-19

    /NETL managed National Mineral Sequestration Working Group we have already significantly improved our understanding of mineral carbonation. Group members at the Albany Research Center have recently shown that carbonation of olivine and serpentine, which naturally occurs over geological time (i.e., 100,000s of years), can be accelerated to near completion in hours. Further process refinement will require a synergetic science/engineering approach that emphasizes simultaneous investigation of both thermodynamic processes and the detailed microscopic, atomic-level mechanisms that govern carbonation kinetics. Our previously funded Phase I Innovative Concepts project demonstrated the value of advanced quantum-mechanical modeling as a complementary tool in bridging important gaps in our understanding of the atomic/molecular structure and reaction mechanisms that govern CO{sub 2} mineral sequestration reaction processes for the model Mg-rich lamellar hydroxide feedstock material Mg(OH){sub 2}. In the present simulation project, improved techniques and more efficient computational schemes have allowed us to expand and augment these capabilities and explore more complex Mg-rich, lamellar hydroxide-based feedstock materials, including the serpentine-based minerals. These feedstock materials are being actively investigated due to their wide availability, and low-cost CO{sub 2} mineral sequestration potential. Cutting-edge first principles quantum chemical, computational solid-state and materials simulation methodology studies proposed herein, have been strategically integrated with our new DOE supported (ASU-Argonne National Laboratory) project to investigate the mechanisms that govern mineral feedstock heat-treatment and aqueous/fluid-phase serpentine mineral carbonation in situ. This unified, synergetic theoretical and experimental approach will provide a deeper understanding of the key reaction mechanisms than either individual approach can alone. Ab initio techniques will also

  8. ENHANCING THE ATOMIC-LEVEL UNDERSTANDING OF CO2 MINERAL SEQUESTRATION MECHANISMS VIA ADVANCED COMPUTATIONAL MODELING

    SciTech Connect

    A.V.G. Chizmeshya

    2002-12-19

    /NETL managed National Mineral Sequestration Working Group we have already significantly improved our understanding of mineral carbonation. Group members at the Albany Research Center have recently shown that carbonation of olivine and serpentine, which naturally occurs over geological time (i.e., 100,000s of years), can be accelerated to near completion in hours. Further process refinement will require a synergetic science/engineering approach that emphasizes simultaneous investigation of both thermodynamic processes and the detailed microscopic, atomic-level mechanisms that govern carbonation kinetics. Our previously funded Phase I Innovative Concepts project demonstrated the value of advanced quantum-mechanical modeling as a complementary tool in bridging important gaps in our understanding of the atomic/molecular structure and reaction mechanisms that govern CO{sub 2} mineral sequestration reaction processes for the model Mg-rich lamellar hydroxide feedstock material Mg(OH){sub 2}. In the present simulation project, improved techniques and more efficient computational schemes have allowed us to expand and augment these capabilities and explore more complex Mg-rich, lamellar hydroxide-based feedstock materials, including the serpentine-based minerals. These feedstock materials are being actively investigated due to their wide availability, and low-cost CO{sub 2} mineral sequestration potential. Cutting-edge first principles quantum chemical, computational solid-state and materials simulation methodology studies proposed herein, have been strategically integrated with our new DOE supported (ASU-Argonne National Laboratory) project to investigate the mechanisms that govern mineral feedstock heat-treatment and aqueous/fluid-phase serpentine mineral carbonation in situ. This unified, synergetic theoretical and experimental approach will provide a deeper understanding of the key reaction mechanisms than either individual approach can alone. Ab initio techniques will also

  9. Advancing the understanding of plasma transport in mid-size stellarators

    NASA Astrophysics Data System (ADS)

    Hidalgo, Carlos; Talmadge, Joseph; Ramisch, Mirko; TJ-II, the; HXS; TJ-K Teams

    2017-01-01

    The tokamak and the stellarator are the two main candidate concepts for magnetically confining fusion plasmas. The flexibility of the mid-size stellarator devices together with their unique diagnostic capabilities make them ideally suited to study the relation between magnetic topology, electric fields and transport. This paper addresses advances in the understanding of plasma transport in mid-size stellarators with an emphasis on the physics of flows, transport control, impurity and particle transport and fast particles. The results described here emphasize an improved physics understanding of phenomena in stellarators that complements the empirical approach. Experiments in mid-size stellarators support the development of advanced plasma scenarios in Wendelstein 7-X (W7-X) and, in concert with better physics understanding in tokamaks, may ultimately lead to an advance in the prediction of burning plasma behaviour.

  10. Beyond Homophily: A Decade of Advances in Understanding Peer Influence Processes

    ERIC Educational Resources Information Center

    Brechwald, Whitney A.; Prinstein, Mitchell J.

    2011-01-01

    This article reviews empirical and theoretical contributions to a multidisciplinary understanding of peer influence processes in adolescence over the past decade. Five themes of peer influence research from this decade were identified, including a broadening of the range of behaviors for which peer influence occurs, distinguishing the sources of…

  11. EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF NEW POWER CYCLES AND ADVANCED FALLING FILM HEAT EXCHANGERS

    SciTech Connect

    Arsalan Razani; Kwang J. Kim

    2000-10-28

    The annual progress report for the period of October 1, 1999 to September 30, 2000 on DOE/UNM grant number DE-FG26-98FT40148 discusses the progress on both the theoretical analysis of advanced power cycles and the experimental investigation of advanced falling film heat exchangers. The previously developed computer program for the triple cycle, based on the air standard cycle assumption, was modified to include actual air composition (%77.48 N{sub 2}, %20.59 O{sub 2}, %1.9 H{sub 2}O, and %0.03 CO{sub 2}). The actual combustion products were used in exergy analysis of the triple cycle. The effect of steam injection into the combustion chamber on its irreversibility, and the irreversibility of the entire cycle, was evaluated. A more practical fuel inlet condition and a better position of the feedwater heater in the steam cycle were used in the modified cycle. The effect of pinch point and the temperature difference between the combustion products, as well as the steam in the heat recovery steam generator on irreversibility of the cycle were evaluated. Design, construction, and testing of the multitube horizontal falling film condenser facility were completed. Two effective heat transfer additives (2-ethyl-1-hexanol and alkyl amine) were identified and tested for steam condensation. The test results are included. The condenser was designed with twelve tubes in an array of three horizontals and four verticals, with a 2-inch horizontal and 1.5-inch vertical in-line pitch. By using effective additives, the condensation heat transfer rate can be augmented as much as 30%, as compared to a heat transfer that operated without additives under the same operating condition. When heat transfer additives function effectively, the condensate-droplets become more dispersed and have a smaller shape than those produced without additives. These droplets, unlike traditional turbulence, start at the top portion of the condenser tubes and cover most of the tubes. Such a flow behavior can

  12. Understanding and Predicting Plutonium Alloys Aging: A Coupled Experimental and Theoretical Approach

    NASA Astrophysics Data System (ADS)

    Baclet, N.; Pochet, P.; Faure, Ph.; Valot, C.; Gosmain, L.; Valot, Ch.; Flament, J. L.; Berthier, C.

    2003-07-01

    Understanding plutonium aging is a real challenge that requires developing very ambitious modeling and experiments. Examples of the different techniques developed and the physical values that can be reached are presented here.

  13. Mentalization and attachment representations: a theoretical contribution to the understanding of reactive attachment disorder.

    PubMed

    Mikic, Natalie; Terradas, Miguel M

    2014-01-01

    This article proposes an understanding of children with reactive attachment disorder (RAD) through psychoanalytic thought and mentalization theory. RAD is presented followed by a discussion on attachment and the need for a better understanding of this disorder. Theories from British psychoanalytic thinkers are used to describe what might be transpiring in the early relationship between mother and child. Particular attention is given to how children's internal objects are influenced by a compromised early mother-child relationship.

  14. Benzthiazoline-2-thione (BTT) revisited: An experimental and theoretical endeavor to understand UV-spectra

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, Prasanta; Bhattacharya, Barnali; Majhi, Koushik; Majee, Prakash; Sarkar, Utpal; Motin Seikh, Md.

    2017-10-01

    Benzthiazoline-2-thione (BTT) and its derivatives are industrially and biologically important heterocyclic organic compounds. Here, we present both experimental and theoretical investigations. The IR and UV spectroscopic measurements unambiguously show the keto-enol tautomerization. Here, for the first time we report spectral changes of BTT in different solvents using quantum chemical calculations and hence reproduce both the hypsochromic and bathochromic shifts in the UV spectra which are sensitive to the nature of hydrogen bonding between solvent and BTT. Our calculations also reveal that the lowest energy transition is associated with a π → π∗ rather than a n → π∗ transition suggested to explain experimental results.

  15. Advances in the understanding of dairy and cheese flavors: Symposium Introduction

    USDA-ARS?s Scientific Manuscript database

    A symposium titled “Advances in the Understanding of Dairy and Cheese Flavors” was held in September 2013 at the American Chemical Society’s 246th National Meeting in Indianapolis, IN. The symposium, which was sponsored by the Division of Agricultural and Food Chemistry, was to discuss the state of...

  16. 48 CFR 1552.215-74 - Advanced understanding-uncompensated time.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... following provision or one substantially the same as the following provision: Advanced Understanding... uncompensated time, and the formula elements in paragraph (b) below, apply only to exempt personnel working at..., calculated in accordance with the following formula will be made to the contract amount. Formula: Adjustment...

  17. 48 CFR 1552.215-74 - Advanced understanding-uncompensated time.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... following provision or one substantially the same as the following provision: Advanced Understanding... uncompensated time, and the formula elements in paragraph (b) below, apply only to exempt personnel working at..., calculated in accordance with the following formula will be made to the contract amount. Formula: Adjustment...

  18. The Effect of Explicit Embedded Reflective Instruction on Nature of Science Understandings in Advanced Science Students

    ERIC Educational Resources Information Center

    Koksal, Mustafa Serdar; Cakiroglu, Jale; Geban, Omer

    2013-01-01

    The purpose of this study is to investigate the effectiveness of explicit-embedded-reflective (EER) instruction in nature of science (NOS) understandings of ninth-grade advanced science students. This study was conducted with 71 students, who were divided into three groups, by using non-equivalent quasi-experimental design. In the treatment…

  19. The Effect of Explicit Embedded Reflective Instruction on Nature of Science Understandings in Advanced Science Students

    ERIC Educational Resources Information Center

    Koksal, Mustafa Serdar; Cakiroglu, Jale; Geban, Omer

    2013-01-01

    The purpose of this study is to investigate the effectiveness of explicit-embedded-reflective (EER) instruction in nature of science (NOS) understandings of ninth-grade advanced science students. This study was conducted with 71 students, who were divided into three groups, by using non-equivalent quasi-experimental design. In the treatment…

  20. 48 CFR 1552.215-74 - Advanced understanding-uncompensated time.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Advanced understanding-uncompensated time. 1552.215-74 Section 1552.215-74 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions...

  1. Recent Advances in Our Understanding of the Environmental, Epidemiological, Immunological, and Clinical Dimensions of Coccidioidomycosis

    PubMed Central

    Nguyen, Chinh; Barker, Bridget Marie; Hoover, Susan; Nix, David E.; Ampel, Neil M.; Frelinger, Jeffrey A.; Orbach, Marc J.

    2013-01-01

    SUMMARY Coccidioidomycosis is the endemic mycosis caused by the fungal pathogens Coccidioides immitis and C. posadasii. This review is a summary of the recent advances that have been made in the understanding of this pathogen, including its mycology, genetics, and niche in the environment. Updates on the epidemiology of the organism emphasize that it is a continuing, significant problem in areas of endemicity. For a variety of reasons, the number of reported coccidioidal infections has increased dramatically over the past decade. While continual improvements in the fields of organ transplantation and management of autoimmune disorders and patients with HIV have led to dilemmas with concurrent infection with coccidioidomycosis, they have also led to advances in the understanding of the human immune response to infection. There have been some advances in therapeutics with the increased use of newer azoles. Lastly, there is an overview of the ongoing search for a preventative vaccine. PMID:23824371

  2. A Theoretical Framework for Research in Algebra: Modification of Janvier's "Star" Model of Function Understanding.

    ERIC Educational Resources Information Center

    Bowman, Anita H.

    A pentagonal model, based on the star model of function understanding of C. Janvier (1987), is presented as a framework for the design and interpretation of research in the area of learning the concept of mathematical function. The five vertices of the pentagon correspond to five common representations of mathematical function: (1) graph; (2)…

  3. Understanding Chemistry Professors' Use of Educational Technologies: An Activity Theoretical Approach

    ERIC Educational Resources Information Center

    Kahveci, Ajda; Gilmer, Penny J.; Southerland, Sherry A.

    2008-01-01

    The aim of this study is to understand the influences on chemistry professors' use of educational technology. For this, we use activity theory to focus on two university chemistry professors and the broader activity system in which they work. We analyse their beliefs and past experiences related to teaching, learning, and technology as well as…

  4. Understanding Manual-Based Behavior Therapy: Some Theoretical Foundations of Parent-Child Interaction Therapy.

    ERIC Educational Resources Information Center

    Greco, Laurie A.; Sorrell, John T.; McNeil, Cheryl B.

    2001-01-01

    Provides a model of understanding and evaluating manualized treatments by beginning with a review of the theory and data-driven principles upon which one treatment, Parent-Child Interaction Therapy (PCIT), is based. As a point of illustration, several principles of PCIT, such as reinforcement, punishment, and stimulus control, are highlighted, and…

  5. Gender Structure and Women's Agency: Toward Greater Theoretical Understanding of Education for Transformation

    ERIC Educational Resources Information Center

    Stromquist, Nelly P.

    2015-01-01

    Under the research radar, and yet highly influential in transformation of practices concerning the social understanding and enactment of gender, are women-led non-governmental organizations (WNGOs). Their continued efforts to reconfigure gender identities and their impact on public policy formation have expanded notions of citizenship and…

  6. Gender Structure and Women's Agency: Toward Greater Theoretical Understanding of Education for Transformation

    ERIC Educational Resources Information Center

    Stromquist, Nelly P.

    2015-01-01

    Under the research radar, and yet highly influential in transformation of practices concerning the social understanding and enactment of gender, are women-led non-governmental organizations (WNGOs). Their continued efforts to reconfigure gender identities and their impact on public policy formation have expanded notions of citizenship and…

  7. College Students' Achievement and Understanding of Experimental and Theoretical Probability: The Role of Tasks

    ERIC Educational Resources Information Center

    Papaieronymou, Irini

    2012-01-01

    This study examined the role of particular tasks implemented through two instructional methods on college students' "achievement" and understanding of probability. A mixed methods design that utilized a pre-test and post-test was used. This included treatment and control groups, each comprised of students in three sections of an…

  8. Direct-to-consumer-advertising of prescription medicines: a theoretical approach to understanding.

    PubMed

    Harker, Michael; Harker, Debra

    2007-01-01

    The pharmaceutical industry is a leader in research and development investment. New treatments need to be communicated to the market, and consumers are increasingly interested in learning about new drugs. Direct to consumer advertising of prescription medicines (DTCA) is a controversial practice where many of the arguments for and against are not supported by strong evidence. This paper aims to contribute to a research agenda that is forming in this area. The paper reports on a systematic review that was conducted and applies accepted theoretical models to the DTCA context. The systematic review methodology is widely accepted in the medical sector and is successfully applied here in the marketing field. The hierarchy of effects model is specifically applied to DTCA with a clear emphasis on consumer rights, empowerment, protection and knowledge. This paper provides healthcare practitioners with insight into how consumers process DTCA messages and provides guidance into how to assist in this message processing.

  9. Understanding Confounding Effects in Linguistic Coordination: An Information-Theoretic Approach

    PubMed Central

    Gao, Shuyang; Ver Steeg, Greg; Galstyan, Aram

    2015-01-01

    We suggest an information-theoretic approach for measuring stylistic coordination in dialogues. The proposed measure has a simple predictive interpretation and can account for various confounding factors through proper conditioning. We revisit some of the previous studies that reported strong signatures of stylistic accommodation, and find that a significant part of the observed coordination can be attributed to a simple confounding effect—length coordination. Specifically, longer utterances tend to be followed by longer responses, which gives rise to spurious correlations in the other stylistic features. We propose a test to distinguish correlations in length due to contextual factors (topic of conversation, user verbosity, etc.) and turn-by-turn coordination. We also suggest a test to identify whether stylistic coordination persists even after accounting for length coordination and contextual factors. PMID:26115446

  10. Interfaces in Heterogeneous Catalysts: Advancing Mechanistic Understanding through Atomic-Scale Measurements.

    PubMed

    Gao, Wenpei; Hood, Zachary D; Chi, Miaofang

    2017-04-18

    interfaces and providing deeper insight for fine-tuning and optimizing catalyst properties. Scanning transmission electron microscopy (STEM) has long been a primary characterization technique used for studying nanomaterials because of its exceptional imaging resolution and simultaneous chemical analysis. Over the past decade, advances in STEM, that is, the commercialization of both aberration correctors and monochromators, have significantly improved the spatial and energy resolution. Imaging atomic structures with subangstrom resolution and identifying chemical species with single-atom sensitivity are now routine for STEM. These advancements have greatly benefitted catalytic research. For example, the roles of lattice strain and surface elemental distribution and their effect on catalytic stability and reactivity have been well documented in bimetallic catalysts. In addition, three-dimensional atomic structures revealed by STEM tomography have been integrated in theoretical modeling for predictive catalyst NP design. Recent developments in stable electronic and mechanical devices have opened opportunities to monitor the evolution of catalysts in operando under synthesis and reaction conditions; high-speed direct electron detectors have achieved sub-millisecond time resolutions and allow for rapid structural and chemical changes to be captured. Investigations of catalysts using these latest microscopy techniques have provided new insights into atomic-level catalytic mechanisms. Further integration of new microscopy methods is expected to provide multidimensional descriptions of interfaces under relevant synthesis and reaction conditions. In this Account, we discuss recent insights on understanding catalyst activity, selectivity, and stability using advanced STEM techniques, with an emphasis on how critical interfaces dictate the performance of precious metal-based heterogeneous catalysts. The role of extended interfacial structures, including those between core and shell

  11. Discussions of Life Expectancy and Changes in Illness Understanding in Patients With Advanced Cancer.

    PubMed

    Epstein, Andrew S; Prigerson, Holly G; O'Reilly, Eileen M; Maciejewski, Paul K

    2016-07-10

    Accurate illness understanding enables patients to make informed decisions. Evidence of the influence of prognostic discussions on the accuracy of illness understanding by patients would demonstrate the value of discussions. Recent and past oncology provider-patient discussions about prognosis/life expectancy were examined for their association with changes in illness understanding by patients. Patients (N = 178) with advanced cancers refractory to prior chemotherapy whom oncologists expected to die within 6 months were interviewed before and after a visit in which cancer restaging scan results were discussed. Illness understanding scores were the sum of four indicator variables: patient terminal illness acknowledgment, recognition of incurable disease status, knowledge of the advanced stage of the disease, and expectation to live months as opposed to years. Before the restaging scan visit, nine (5%) of 178 patients had completely accurate illness understanding (ie, correctly answered each of the four illness understanding questions). Eighteen patients (10%) reported only recent discussions of prognosis/life expectancy with their oncologists; 68 (38%) reported only past discussions; 24 (13%) reported both recent and past discussions; and 68 (38%) reported that they never had discussions of prognosis/life expectancy with their oncologists. After adjustment for potential confounders (ie, education and race/ethnicity), analysis identified significant, positive changes in illness understanding scores for patients in groups that reported recent only (least-squares mean change score, 0.62; 95% CI, 0.23 to 1.01; P = .002) and both recent and past (least-squares mean change score, 0.37; 95% CI, 0.04 to 0.70; P = 0.028) discussions of prognosis/life expectancy with their oncologists. Patients with advanced cancer who report recent discussions of prognosis/life expectancy with their oncologists come to have a better understanding of the terminal nature of their illnesses.

  12. Understanding uncertainty in seagrass injury recovery: an information-theoretic approach.

    PubMed

    Uhrin, Amy V; Kenworthy, W Judson; Fonseca, Mark S

    2011-06-01

    Vessel groundings cause severe, persistent gaps in seagrass beds. Varying degrees of natural recovery have been observed for grounding injuries, limiting recovery prediction capabilities, and therefore, management's ability to focus restoration efforts where natural recovery is unlikely. To improve our capacity for predicting seagrass injury recovery, we used an information-theoretic approach to evaluate the relative contribution of specific injury attributes to the natural recovery of 30 seagrass groundings in Florida Keys National Marine Sanctuary, Florida, USA. Injury recovery was defined by three response variables examined independently: (1) initiation of seagrass colonization, (2) areal contraction, and (3) sediment in-filling. We used a global model and all possible subsets for four predictor variables: (1) injury age, (2) original injury volume, (3) original injury perimeter-to-area ratio, and (4) wave energy. Successional processes were underway for many injuries with fast-growing, opportunistic seagrass species contributing most to colonization. The majority of groundings that exhibited natural seagrass colonization also exhibited areal contraction and sediment in-filling. Injuries demonstrating colonization, contraction, and in-filling were on average older and smaller, and they had larger initial perimeter-to-area ratios. Wave energy was highest for colonizing injuries. The information-theoretic approach was unable to select a single "best" model for any response variable. For colonization and contraction, injury age had the highest relative importance as a predictor variable; wave energy appeared to be associated with second-order effects, such as sediment in-filling, which in turn, facilitated seagrass colonization. For sediment in-filling, volume and perimeter-to-area ratio had similar relative importance as predictor variables with age playing a lesser role than seen for colonization and contraction. Our findings confirm that these injuries

  13. Cooperative Catalysis of Combined Systems of Transition-Metal Complexes with Lewis Acids: Theoretical Understanding.

    PubMed

    Guan, Wei; Zeng, Guixiang; Kameo, Hajime; Nakao, Yoshiaki; Sakaki, Shigeyoshi

    2016-10-01

    The combination of transition-metal complexes and Lewis acids has been recently applied to several catalytic reactions, in which the Lewis acid plays a crucial role as a non-innocent additive to accelerate the reaction. In this review article, the reasons for the acceleration by the Lewis acid are discussed based on our recent theoretical studies. In the H-H σ-bond activation of a dihydrogen molecule by a nickel(0)-borane complex, the empty p orbital of the borane moiety interacts with the H-H σ bonding MO to form charge transfer (CT) from the dihydrogen molecule to the borane moiety to accelerate the reaction. In the B-F σ-bond activation of BF3 by a platinum(0)-bisphosphine complex, the second BF3 molecule interacts with the F atom that is dissociating from the B atom to stabilize the transition state and product by the CT from the F atom to the second BF3 . In this reaction, the substrate BF3 plays a crucial role as the Lewis acid to accelerate the activation of the B-F σ bond. In the nickel-catalyzed decyanative coupling of arylcarboxybenzonitriles with acetylenes, two molecules of the aluminum Lewis acid interact with the cyano N atom and the carbonyl O atom of the substrate to stabilize the transition state and intermediate. In the nickel-catalyzed alkylation of aromatic amides with alkenes, the Lewis acid enhances the para regioselectivity of alkylation by interacting with the carbonyl O atom. In the nickel-catalyzed carboxylation of sp(3) carbon and sp carbon atoms with carbon dioxide, not the σ-bond activation but the insertion reaction of carbon dioxide into the metal-carbon bond is accelerated by the Lewis acid by interacting with the O atom of carbon dioxide, because the CT from the metal-carbon bond to carbon dioxide is enhanced by the interaction. This theoretical knowledge suggests that the combination of transition-metal complex and Lewis acid can broaden the application range of transition-metal complex as catalyst. © 2016 The Chemical

  14. Understanding Skill in EVA Mass Handling. Volume 1; Theoretical and Operational Foundations

    NASA Technical Reports Server (NTRS)

    Riccio, Gary; McDonald, Vernon; Peters, Brian; Layne, Charles; Bloomberg, Jacob

    1997-01-01

    This report describes the theoretical and operational foundations for our analysis of skill in extravehicular mass handling. A review of our research on postural control, human-environment interactions, and exploratory behavior in skill acquisition is used to motivate our analysis. This scientific material is presented within the context of operationally valid issues concerning extravehicular mass handling. We describe the development of meaningful empirical measures that are relevant to a special class of nested control systems: manual interactions between an individual and the substantial environment. These measures are incorporated into a unique empirical protocol implemented on NASA's principal mass handling simulator, the precision air-bearing floor, in order to evaluate skill in extravehicular mass handling. We discuss the components of such skill with reference to the relationship between postural configuration and controllability of an orbital replacement unit, the relationship between orbital replacement unit control and postural stability, the relationship between antecedent and consequent movements of an orbital replacement unit, and the relationship between antecedent and consequent postural movements. Finally, we describe our expectations regarding the operational relevance of the empirical results as it pertains to extravehicular activity tools, training, monitoring, and planning.

  15. Recent theoretical progress in understanding coherent structures in edge and SOL turbulence

    NASA Astrophysics Data System (ADS)

    Krasheninnikov, S. I.; D'Ippolito, D. A.; Myra, J. R.

    2008-10-01

    In this paper we review some theoretical aspects of the dynamics of the mesoscale filaments extending along the magnetic field lines in the edge plasma, which are often called ‘blobs’. We start with a brief historical survey of experimental data and the main ideas on edge and SOL plasma transport, which finally evolved into the modern paradigm of convective very-intermittent cross-field edge plasma transport. We show that both extensive analytic treatments and numerical simulations demonstrate that plasma blobs with enhanced pressure can be convected coherently towards the wall. The mechanism of convection is related to an effective gravity force (e.g. owing to magnetic curvature effects), which causes plasma polarization and a corresponding E× B convection. The impacts of different effects (e.g. X-point magnetic geometry, plasma collisionality, plasma beta, etc.) on blob dynamics are considered. Theory and simulation predict, both for current tokamaks and for ITER, blob propagation speeds and cross-field sizes to be of the order of a few hundred meters per second and a centimeter, respectively, which are in reasonable agreement with available experimental data. Moreover, the concept of blobs as a fundamental entity of convective transport in the scrape-off layer provides explanations for observed outwards convective transport, intermittency and non-Gaussian statistics in edge plasmas, and enhanced wall recycling in both toroidal and linear machines.

  16. A Changing Landscape of Advanced Prostate Cancer: Understanding Mechanisms of Resistance to Potent Hormonal Therapies

    DTIC Science & Technology

    2016-10-01

    1 AWARD NUMBER: W81XWH-13-1-0275 TITLE: A Changing Landscape of Advanced Prostate Cancer: Understanding Mechanisms of Resistance to Potent...TYPE Annual 3. DATES COVERED 30Sep2015 - 29Sep2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-13-1-0275 A Changing Landscape of Advanced...The mutational landscape of CRPC-NE was similar to CRPC-Adeno (Figure 1c), but also consistent with published studies of CRPC-NE including

  17. Understanding the advances in biology of orthodontic tooth movement for improved ortho-perio interdisciplinary approach

    PubMed Central

    Patil, Anand K.; Shetty, Adarsh S.; Setty, Swati; Thakur, Srinath

    2013-01-01

    This article provides an insight on detailed current advances in molecular understandings of periodontal ligament cells and the influence of orthodontic force on them in the light of recent advances in molecular and genetic sciences. It sequentially unfolds the cellular events beginning from the mechanical force initiated events of cellular responses to bone remodeling. It also highlights the risks and limitations of orthodontic treatment in certain periodontal conditions, the important areas of team work, orthodontic expectations from periodontal treatment and the possibility of much more future combined research to improve the best possible periodontal health and esthetic outcome of the patient. PMID:24049330

  18. The Interaction Between an Insoluble Particle and an Advancing Solid/Liquid Interface: Micro-Gravity Experiments and Theoretical Developments

    NASA Technical Reports Server (NTRS)

    Catalina, Adrian V.; Ssen, Subhayu; Stefanescu, Doru M.

    2003-01-01

    The interaction of an insoluble particle with an advancing solid/liquid interface (SLI) has been a subject of investigation for the past four decades. While the original interest stemmed from geology applications (e.g., frost heaving in soil), researchers soon realized that the complex science associated with such an interaction is relevant to many other scientific fields encompassing metal matrix composites (MMCs), high temperature superconductors, inclusion management in steel, growth of monotectics, and preservation of biological cells. During solidification of a liquid containing an insoluble particle, three distinct interaction phenomena have been experimentally observed: instantaneous engulfment of the particle, continuous pushing, and particle pushing followed by engulfment. It was also observed that for given experimental conditions and particle size there is a critical solidification velocity, V(sub cr), above which a particle is engulfed. During solidification of MMCs pushing leads to particle agglomeration at the grain boundaries and this has detrimental effects on mechanical properties of the casting. Consequently, the process must be designed for instantaneous engulfment to occur. This implies the development of accurate theoretical models to predict V(sub cr), and perform benchmark experiments to test the validity of such models. Although considerable progress has been made in understanding the pushing/engulfment phenomenon (PEP), its quantification in terms of the material and processing parameters remains a focus of research. Since natural convection currents occurring during terrestrial solidification experiments complicate the study of PEP, execution of experiments on the International Space Station (ISS) has been approved and funded by NASA. Extensive terrestrial (1g) experiments and preliminary micro-gravity (mu g) experiments on two space shuttle missions have been conducted in preparation for future experiments on the ISS. The investigated

  19. The Interaction Between an Insoluble Particle and an Advancing Solid/Liquid Interface: Micro-Gravity Experiments and Theoretical Developments

    NASA Technical Reports Server (NTRS)

    Catalina, Adrian V.; Ssen, Subhayu; Stefanescu, Doru M.

    2003-01-01

    The interaction of an insoluble particle with an advancing solid/liquid interface (SLI) has been a subject of investigation for the past four decades. While the original interest stemmed from geology applications (e.g., frost heaving in soil), researchers soon realized that the complex science associated with such an interaction is relevant to many other scientific fields encompassing metal matrix composites (MMCs), high temperature superconductors, inclusion management in steel, growth of monotectics, and preservation of biological cells. During solidification of a liquid containing an insoluble particle, three distinct interaction phenomena have been experimentally observed: instantaneous engulfment of the particle, continuous pushing, and particle pushing followed by engulfment. It was also observed that for given experimental conditions and particle size there is a critical solidification velocity, V(sub cr), above which a particle is engulfed. During solidification of MMCs pushing leads to particle agglomeration at the grain boundaries and this has detrimental effects on mechanical properties of the casting. Consequently, the process must be designed for instantaneous engulfment to occur. This implies the development of accurate theoretical models to predict V(sub cr), and perform benchmark experiments to test the validity of such models. Although considerable progress has been made in understanding the pushing/engulfment phenomenon (PEP), its quantification in terms of the material and processing parameters remains a focus of research. Since natural convection currents occurring during terrestrial solidification experiments complicate the study of PEP, execution of experiments on the International Space Station (ISS) has been approved and funded by NASA. Extensive terrestrial (1g) experiments and preliminary micro-gravity (mu g) experiments on two space shuttle missions have been conducted in preparation for future experiments on the ISS. The investigated

  20. A Theoretical Framework for Understanding the Effects of Saharan Mineral Dust Aerosols on African Easterly Waves

    NASA Astrophysics Data System (ADS)

    Nathan, T. R.; Grogan, D.; Chen, S.

    2013-12-01

    Studies have shown that a large fraction of the intense hurricanes observed over the Atlantic Ocean originate as African easterly waves (AEWs). Of the many processes that affect the propagation, growth and structure of AEWs, the effects of Saharan mineral dust aerosols on AEWs remains an outstanding scientific problem. With this in mind, a new theoretical framework is presented that illuminates causal relationships between Saharan dust and the linear dynamics of AEWs. The framework is built on a quasi-geostrophic system governed by coupled equations for potential vorticity, temperature, and dust continuity. The radiative-dust heating rate accounts for both shortwave and longwave radiative transfer. The source of dust is due to surface emission, which depends on surface wind; the sinks of dust are due to sedimentation and dry deposition. A perturbation analysis yields analytical expressions for the propagation and growth characteristics of the model's AEWs. These expressions are functions of vertically and meridionally averaged wave activity, which depends on wave spatial structure, dust-radiative heating, and the background distributions of wind, temperature, and dust mixing ratio. More specifically, the propagation and growth of the AEWs depend on the amount of dust lofted from the surface by the wind, and the meridional and vertical gradients of the basic state dust distribution, which are modulated by the Doppler-shifted frequency. Idealized cases are presented that show the effects of Saharan dust on the propagation, group velocity, growth, structure, and wave fluxes of AEWs. The clarity of the expressions connecting dust aerosols to the linear properties of AEWs provides an important interpretive tool for analyzing results obtained from comprehensive model simulations of AEWs, such as those produced by the Weather Research and Forecasting (WRF) model.

  1. Theoretical and Experimental Approaches to Understanding the Anomalous Distribution of Oxygen Isotopes in the Solar System

    NASA Astrophysics Data System (ADS)

    Dominguez, Gerardo; Christensen, Elizabeth; Boyer, Charisa; Park, Manesseh; Benitez, Ezra; Nunn, Morgan; Thiemens, Mark H.; Jackson, Terri

    2016-06-01

    Decades of careful laboratory analysis of primitive meteorites have revealed an intriguing and unexplained pattern in the distribution of oxygen isotopes in the solar system. With the recent analysis of solar wind oxygen by NASA’s Genesis mission, it appears that the Sun has a distinct oxygen isotopic composition from the terrestrial planets, asteroids, and comets. These differences cannot be explained by mass-dependent diffusion and require a physical-chemical mechanism or mechanisms that separate oxygen isotopes in a non-mass dependent manner.Several hypothesis have been proposed to explain the anomalous distribution. Photochemical self-shielding of CO may explain the anomalous distribution, however, this mechanism has key weaknesses including the requirement of a very fine tuned timescale to explain the isotopic differences between the Sun and bulk of the terrestrial planets. Recently, attention has been directed at understanding specific chemical reactions that occur on interstellar dust grains due to their similarities with non-equilibrium photochemical reactions believed to be responsible for the mass-independent isotopic fractionation patterns observed in Earth’s atmosphere. A specific focus has been directed towards understanding the formation of H2O because some of its precursor (HO2, and O3) are well-known to acquire mass-independent isotopic signatures when formed in the gas-phase.In this presentation, I describe a series of laboratory astrophysical experiments whose goal is to understand the distribution of oxygen isotopes in the solar system and perhaps, by extension, the distribution in other planetary systems. Preliminary results for the isotopic composition of O3 formed at 5K will be presented as well as the first, to our knowledge, measurements of the isotopic composition of H2O (18O/16O, 17O/16O, D/H) formed at 32K. We find that H2O formed in the astrophysical conditions we simulated acquired an anomalous isotopic composition with a triple

  2. Theoretical Approaches for Understanding the Interplay Between Stress and Chemical Reactivity.

    PubMed

    Kochhar, Gurpaul S; Heverly-Coulson, Gavin S; Mosey, Nicholas J

    2015-01-01

    The use of mechanical stresses to induce chemical reactions has attracted significant interest in recent years. Computational modeling can play a significant role in developing a comprehensive understanding of the interplay between stresses and chemical reactivity. In this review, we discuss techniques for simulating chemical reactions occurring under mechanochemical conditions. The methods described are broadly divided into techniques that are appropriate for studying molecular mechanochemistry and those suited to modeling bulk mechanochemistry. In both cases, several different approaches are described and compared. Methods for examining molecular mechanochemistry are based on exploring the force-modified potential energy surface on which a molecule subjected to an external force moves. Meanwhile, it is suggested that condensed phase simulation methods typically used to study tribochemical reactions, i.e., those occurring in sliding contacts, can be adapted to study bulk mechanochemistry.

  3. Understanding the impact of political violence in childhood: a theoretical review using a social identity approach.

    PubMed

    Muldoon, Orla T

    2013-12-01

    The present paper reviews the literature that has assessed the psychological impact of political violence on children. Concern for those growing up in situations of political violence has resulted in two areas of research within psychology: the first considers children as victims of conflict and considers the mental health consequences of political violence. The second considers children as protagonists or aggressors in conflict and considers related moral and attitudinal consequences of exposure to political violence. These two literatures are most often considered separately. Here the two strands of research are brought together using a social identity framework, allowing apparently divergent findings to be integrated into a more coherent understanding of the totality of consequences for children and young people growing up in situations of armed conflict. © 2013.

  4. Revisiting widowhood in later life: changes in patterns and profiles, advances in research and understanding.

    PubMed

    Martin-Matthews, Anne

    2011-09-01

    This analysis reviews the ways in which both the experience of widowhood in old age and the nature of research on widowhood have changed since the publication of the book Widowhood in Later Life in 1991. Patterns of decline in widowhood in both its duration and incidence in later life are examined. Widowhood research has advanced conceptually by moving beyond understanding widowhood solely in terms of role loss. Life course perspectives, and concepts of multiple narratives and of resilience, have also contributed to the field. New methodologies, including prospective and longitudinal designs involving larger data sets, and more in-depth qualitative studies, have advanced our understanding of complexities and variations in widowhood. These include issues of gender and ethnocultural diversity, as well as the intersection of wealth, health, and class. This article also examines how patterns of labour force affiliation, social policy, and the changing nature of marriage shape widowhood in later life.

  5. Advances in athlete development: understanding conditions of and constraints on optimal practice.

    PubMed

    Baker, Joseph; Young, Bradley W; Mann, David

    2017-08-01

    The development of elite, high performance athletes reflects the complex interaction of biological and genetic factors with important environmental influences. Over the past two decades, discussions of athlete development have largely focused on the role of 'deliberate' practice, and more recently, researchers have begun exploring the means by which practice can be best used to maximize the rate of talent development across the different stages of athlete development. In this article, we summarize recent developments in understanding how athletes maximize practice including (a) antecedents of practice involvement, (b) environmental constraints of practice involvement, (c) the value of diversification for athlete development, (d) and methodological advancements in this area. Collectively, sustained focus on issues of athlete development and researchers' use of more advanced approaches to novel questions extend our understanding of the nuances associated with this process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Drug-induced liver injury: Advances in mechanistic understanding that will inform risk management.

    PubMed

    Mosedale, M; Watkins, P B

    2016-11-09

    Drug-induced liver injury (DILI) is a major public health problem. Intrinsic (dose-dependent) DILI associated with acetaminophen overdose is the number one cause of acute liver failure in the US. However, the most problematic type of DILI impacting drug development is idiosyncratic, occurring only very rarely among treated patients and often only after several weeks or months of treatment with the offending drug. Recent advances in our understanding of the pathogenesis of DILI suggest that three mechanisms may underlie most hepatocyte effects in response to both intrinsic and idiosyncratic DILI drugs: mitochondrial dysfunction, oxidative stress, and alterations in bile acid homeostasis. However, in some cases hepatocyte stress promotes an immune response that results in clinically important idiosyncratic DILI. This review discusses recent advances in our understanding of the pathogenesis of both intrinsic and idiosyncratic DILI as well as emerging tools and techniques that will likely improve DILI risk identification and management.

  7. Understanding social norms and violence in childhood: theoretical underpinnings and strategies for intervention.

    PubMed

    Lilleston, P S; Goldmann, L; Verma, R K; McCleary-Sills, J

    2017-03-01

    Violence in childhood is a widespread human rights violation that crosses cultural, social and economic lines. Social norms, the shared perceptions about others that exist within social groups, are a critical driver that can either prevent or perpetuate violence in childhood. This review defines injunctive and descriptive social norms and lays out a conceptual framework for the relationship between social norms and violence in childhood, including the forces shaping social norms, the mechanisms through which these norms influence violence in childhood (e.g. fear of social sanctions, internalization of normative behavior), and the drivers and maintainers of norms related to violence in childhood. It further provides a review of theory and evidence-based practices for shifting these social norms including strategic approaches (targeting social norms directly, changing attitudes to shift social norms, and changing behavior to shift social norms), core principles (e.g. using public health frameworks), and intervention strategies (e.g. engaging bystanders, involving stakeholders, using combination prevention). As a key driver of violence in childhood, social norms should be an integral component of any comprehensive effort to mitigate this threat to human rights. Understanding how people's perceptions are shaped, propagated, and, ultimately, altered is crucial to preventing violence in childhood.

  8. Understanding the bonding nature of uranyl ion and functionalized graphene: a theoretical study.

    PubMed

    Wu, Qun-Yan; Lan, Jian-Hui; Wang, Cong-Zhi; Xiao, Cheng-Liang; Zhao, Yu-Liang; Wei, Yue-Zhou; Chai, Zhi-Fang; Shi, Wei-Qun

    2014-03-20

    Studying the bonding nature of uranyl ion and graphene oxide (GO) is very important for understanding the mechanism of the removal of uranium from radioactive wastewater with GO-based materials. We have optimized 22 complexes between uranyl ion and GO applying density functional theory (DFT) combined with quasi-relativistic small-core pseudopotentials. The studied oxygen-containing functional groups include hydroxyl, carboxyl, amido, and dimethylformamide. It is observed that the distances between uranium atoms and oxygen atoms of GO (U-OG) are shorter in the anionic GO complexes (uranyl/GO(-/2-)) compared to the neutral GO ones (uranyl/GO). The formation of hydrogen bonds in the uranyl/GO(-/2-) complexes can enhance the binding ability of anionic GO toward uranyl ions. Furthermore, the thermodynamic calculations show that the changes of the Gibbs free energies in solution are relatively more negative for complexation reactions concerning the hydroxyl and carboxyl functionalized anionic GO complexes. Therefore, both the geometries and thermodynamic energies indicate that the binding abilities of uranyl ions toward GO modified by hydroxyl and carboxyl groups are much stronger compared to those by amido and dimethylformamide groups. This study can provide insights for designing new nanomaterials that can efficiently remove radionuclides from radioactive wastewater.

  9. Advances in the understanding of dairy and cheese flavors: symposium introduction.

    PubMed

    Tunick, Michael H; Gummalla, Sanjay

    2014-06-25

    A symposium titled "Advances in the Understanding of Dairy and Cheese Flavors" was held in September 2013 at the American Chemical Society's 246th National Meeting in Indianapolis, IN, USA. The symposium, which was sponsored by the Division of Agricultural and Food Chemistry, was to discuss the state of the art in the detection and quantitation of flavor in dairy products. The authors of two of the presentations have been selected to expand on their talks by submitting full papers about their research.

  10. In search of a theoretical structure for understanding motivation in schizophrenia.

    PubMed

    Medalia, Alice; Brekke, John

    2010-09-01

    This themed issue considers different ways to conceptualize the motivational impairment that is a core negative symptom of schizophrenia. Motivational impairment has been linked to poor functional outcome, thus it is important to understand the nature and causes of motivational impairment in order to develop better treatment strategies to enhance motivation and engage patients in the process of recovery. Motivation refers to the processes whereby goal-directed activities are instigated and sustained and can be thought of as the product of a complex interaction of physiological processes and social contextual variables. In this issue, the physiological processes of motivation are the focus of Barch and Dowd, who highlight the role of prefrontal and subcortical mesolimbic dopamine systems in incentive-based learning and the difficulties people with schizophrenia have using internal representations of relevant experiences and goals to drive the behavior that should allow them to obtain desired outcomes. The articles in this issue by Choi et al., Nakagami et al., and Silverstein, focus on social contextual or environmental variables that can shape behavior and motivation. Together, these articles highlight the impact of external cues and goal properties on the expectations and values attached to goal outcomes. Expectancy-value and Self-Determination theories provide an overarching framework to accommodate the perspectives and data provided in all these articles. In the following introduction we show how the articles in this themed issue both support the role of expectancies and value in motivation in schizophrenia and elucidate possible deficiencies in the way expectations and value get assigned.

  11. In Search of a Theoretical Structure for Understanding Motivation in Schizophrenia

    PubMed Central

    Medalia, Alice; Brekke, John

    2010-01-01

    This themed issue considers different ways to conceptualize the motivational impairment that is a core negative symptom of schizophrenia. Motivational impairment has been linked to poor functional outcome, thus it is important to understand the nature and causes of motivational impairment in order to develop better treatment strategies to enhance motivation and engage patients in the process of recovery. Motivation refers to the processes whereby goal-directed activities are instigated and sustained and can be thought of as the product of a complex interaction of physiological processes and social contextual variables. In this issue, the physiological processes of motivation are the focus of Barch and Dowd, who highlight the role of prefrontal and subcortical mesolimbic dopamine systems in incentive-based learning and the difficulties people with schizophrenia have using internal representations of relevant experiences and goals to drive the behavior that should allow them to obtain desired outcomes. The articles in this issue by Choi et al., Nakagami et al., and Silverstein, focus on social contextual or environmental variables that can shape behavior and motivation. Together, these articles highlight the impact of external cues and goal properties on the expectations and values attached to goal outcomes. Expectancy-value and Self-Determination theories provide an overarching framework to accommodate the perspectives and data provided in all these articles. In the following introduction we show how the articles in this themed issue both support the role of expectancies and value in motivation in schizophrenia and elucidate possible deficiencies in the way expectations and value get assigned. PMID:20595203

  12. [Temporal trend in understanding of and attitudes to advance directives in patients with chronic diseases].

    PubMed

    Antolín, Albert; Sánchez, Miquel; Miró, Oscar

    2011-01-01

    To describe patients' degree of knowledge about their diseases and advance directives, as well as their willingness to write these documents, among patients with chronic diseases seen in the emergency department. We performed a prospective, comparative, cross-sectional study, without intervention and with consecutive patient inclusion in two periods (2003 and 2008). Demographic and clinical data were recorded. An anonymous interview about patients' knowledge and opinions about their illness and their awareness of advance directives was performed. Previous awareness of advance directives and the predisposition to write these documents were taken as dependent variables, and factors associated with these variables were analyzed. In both periods, 381 patients with similar characteristics were included (191 in 2003 and 190 in 2008). Patients showed greater knowledge of their disease (74% vs 55%, p<0,001), a greater predisposition to take part in medical decisions (62% vs 42%, p<0,001), and higher participation in such decisions (48% vs 35%, p=0.01) in 2008 than in 2003. However, awareness of advance directives was slightly lower (18% vs 23%, p=NS), and willingness to write these documents was unchanged (50% vs 50%, p=NS). Awareness of advance directives was associated with age less than 75 years and having completed secondary school. The predisposition to write advance directives was associated with previous awareness of these documents, considering oneself to be well informed, and wanting greater participation in medical decisions. Patients with chronic diseases showed greater understanding of their disease in the second period but awareness of advance directives and willingness to write these documents remained low. Information on these issues should be improved as an essential part of the physician-patient relationship. 2010 SESPAS. Published by Elsevier Espana. All rights reserved.

  13. Toward theoretical understanding of the fertility preservation decision-making process: examining information processing among young women with cancer.

    PubMed

    Hershberger, Patricia E; Finnegan, Lorna; Altfeld, Susan; Lake, Sara; Hirshfeld-Cytron, Jennifer

    2013-01-01

    Young women with cancer now face the complex decision about whether to undergo fertility preservation. Yet little is known about how these women process information involved in making this decision. The purpose of this article is to expand theoretical understanding of the decision-making process by examining aspects of information processing among young women diagnosed with cancer. Using a grounded theory approach, 27 women with cancer participated in individual, semistructured interviews. Data were coded and analyzed using constant-comparison techniques that were guided by 5 dimensions within the Contemplate phase of the decision-making process framework. In the first dimension, young women acquired information primarily from clinicians and Internet sources. Experiential information, often obtained from peers, occurred in the second dimension. Preferences and values were constructed in the third dimension as women acquired factual, moral, and ethical information. Women desired tailored, personalized information that was specific to their situation in the fourth dimension; however, women struggled with communicating these needs to clinicians. In the fifth dimension, women offered detailed descriptions of clinician behaviors that enhance or impede decisional debriefing. Better understanding of theoretical underpinnings surrounding women's information processes can facilitate decision support and improve clinical care.

  14. Toward theoretical understanding of the fertility preservation decision-making process: Examining information processing among young women with cancer

    PubMed Central

    Hershberger, Patricia E.; Finnegan, Lorna; Altfeld, Susan; Lake, Sara; Hirshfeld-Cytron, Jennifer

    2014-01-01

    Background Young women with cancer now face the complex decision about whether to undergo fertility preservation. Yet little is known about how these women process information involved in making this decision. Objective The purpose of this paper is to expand theoretical understanding of the decision-making process by examining aspects of information processing among young women diagnosed with cancer. Methods Using a grounded theory approach, 27 women with cancer participated in individual, semi-structured interviews. Data were coded and analyzed using constant-comparison techniques that were guided by five dimensions within the Contemplate phase of the decision-making process framework. Results In the first dimension, young women acquired information primarily from clinicians and Internet sources. Experiential information, often obtained from peers, occurred in the second dimension. Preferences and values were constructed in the third dimension as women acquired factual, moral, and ethical information. Women desired tailored, personalized information that was specific to their situation in the fourth dimension; however, women struggled with communicating these needs to clinicians. In the fifth dimension, women offered detailed descriptions of clinician behaviors that enhance or impede decisional debriefing. Conclusion Better understanding of theoretical underpinnings surrounding women’s information processes can facilitate decision support and improve clinical care. PMID:24552086

  15. Understanding creep in sandstone reservoirs - theoretical deformation mechanism maps for pressure solution in granular materials

    NASA Astrophysics Data System (ADS)

    Hangx, Suzanne; Spiers, Christopher

    2014-05-01

    Subsurface exploitation of the Earth's natural resources removes the natural system from its chemical and physical equilibrium. As such, groundwater extraction and hydrocarbon production from subsurface reservoirs frequently causes surface subsidence and induces (micro)seismicity. These effects are not only a problem in onshore (e.g. Groningen, the Netherlands) and offshore hydrocarbon fields (e.g. Ekofisk, Norway), but also in urban areas with extensive groundwater pumping (e.g. Venice, Italy). It is known that fluid extraction inevitably leads to (poro)elastic compaction of reservoirs, hence subsidence and occasional fault reactivation, and causes significant technical, economic and ecological impact. However, such effects often exceed what is expected from purely elastic reservoir behaviour and may continue long after exploitation has ceased. This is most likely due to time-dependent compaction, or 'creep deformation', of such reservoirs, driven by the reduction in pore fluid pressure compared with the rock overburden. Given the societal and ecological impact of surface subsidence, as well as the current interest in developing geothermal energy and unconventional gas resources in densely populated areas, there is much need for obtaining better quantitative understanding of creep in sediments to improve the predictability of the impact of geo-energy and groundwater production. The key problem in developing a reliable, quantitative description of the creep behaviour of sediments, such as sands and sandstones, is that the operative deformation mechanisms are poorly known and poorly quantified. While grain-scale brittle fracturing plus intergranular sliding play an important role in the early stages of compaction, these time-independent, brittle-frictional processes give way to compaction creep on longer time-scales. Thermally-activated mass transfer processes, like pressure solution, can cause creep via dissolution of material at stressed grain contacts, grain

  16. ADVANCING THE FUNDAMENTAL UNDERSTANDING AND SCALE-UP OF TRISO FUEL COATERS VIA ADVANCED MEASUREMENT AND COMPUTATIONAL TECHNIQUES

    SciTech Connect

    Biswas, Pratim; Al-Dahhan, Muthanna

    2012-11-01

    Tri-isotropic (TRISO) fuel particle coating is critical for the future use of nuclear energy produced byadvanced gas reactors (AGRs). The fuel kernels are coated using chemical vapor deposition in a spouted fluidized bed. The challenges encountered in operating TRISO fuel coaters are due to the fact that in modern AGRs, such as High Temperature Gas Reactors (HTGRs), the acceptable level of defective/failed coated particles is essentially zero. This specification requires processes that produce coated spherical particles with even coatings having extremely low defect fractions. Unfortunately, the scale-up and design of the current processes and coaters have been based on empirical approaches and are operated as black boxes. Hence, a voluminous amount of experimental development and trial and error work has been conducted. It has been clearly demonstrated that the quality of the coating applied to the fuel kernels is impacted by the hydrodynamics, solids flow field, and flow regime characteristics of the spouted bed coaters, which themselves are influenced by design parameters and operating variables. Further complicating the outlook for future fuel-coating technology and nuclear energy production is the fact that a variety of new concepts will involve fuel kernels of different sizes and with compositions of different densities. Therefore, without a fundamental understanding the underlying phenomena of the spouted bed TRISO coater, a significant amount of effort is required for production of each type of particle with a significant risk of not meeting the specifications. This difficulty will significantly and negatively impact the applications of AGRs for power generation and cause further challenges to them as an alternative source of commercial energy production. Accordingly, the proposed work seeks to overcome such hurdles and advance the scale-up, design, and performance of TRISO fuel particle spouted bed coaters. The overall objectives of the proposed work are

  17. Recent advances in understanding secondary organic aerosol: Implications for global climate forcing: Advances in Secondary Organic Aerosol

    DOE PAGES

    Shrivastava, Manish; Cappa, Christopher D.; Fan, Jiwen; ...

    2017-06-15

    Anthropogenic emissions and land use changes have modified atmospheric aerosol concentrations and size distributions over time. Understanding preindustrial conditions and changes in organic aerosol due to anthropogenic activities is important because these features (1) influence estimates of aerosol radiative forcing and (2) can confound estimates of the historical response of climate to increases in greenhouse gases. Secondary organic aerosol (SOA), formed in the atmosphere by oxidation of organic gases, represents a major fraction of global submicron-sized atmospheric organic aerosol. Over the past decade, significant advances in understanding SOA properties and formation mechanisms have occurred through measurements, yet current climate modelsmore » typically do not comprehensively include all important processes. Our review summarizes some of the important developments during the past decade in understanding SOA formation. We also highlight the importance of some processes that influence the growth of SOA particles to sizes relevant for clouds and radiative forcing, including formation of extremely low volatility organics in the gas phase, acid-catalyzed multiphase chemistry of isoprene epoxydiols, particle-phase oligomerization, and physical properties such as volatility and viscosity. Several SOA processes highlighted in this review are complex and interdependent and have nonlinear effects on the properties, formation, and evolution of SOA. Current global models neglect this complexity and nonlinearity and thus are less likely to accurately predict the climate forcing of SOA and project future climate sensitivity to greenhouse gases. Efforts are also needed to rank the most influential processes and nonlinear process-related interactions, so that these processes can be accurately represented in atmospheric chemistry-climate models.« less

  18. Discourse analysis: theoretical and historical overview and review of papers in the Journal of Advanced Nursing 1996-2004.

    PubMed

    Traynor, Michael

    2006-04-01

    The aim of the paper is (1) to offer an overview of different theoretical approaches to discourse analysis and (2) to review papers published in the Journal of Advanced Nursing from 1996-2004 in which discourse analysis is identified as a method of data analysis. Discourse analysis offers rigorous approaches to analysing naturally occurring talk and texts. Forms of discourse analysis have developed across broad theoretical bases. Such development has created challenges for researchers wishing to adopt this methodology and readers wishing to evaluate the quality of discourse analytic work. First, key documents which describe the theoretical range of discourse analysis are used to provide (i) a comprehensive overview of the approach, (ii) the identification of categories of discourse analysis and (iii) minimum criteria for determining if an individual paper can realistically claim to be adopting discourse analysis. Secondly, an electronic search followed by hand search of the Journal of Advanced Nursing full-contents between 1996 and 2004 was undertaken. The papers were grouped into the types of approach identified in i, and evaluated to see whether they met the 'minimum criteria' also identified in i. The search of Journal of Advanced Nursing revealed 24 papers where the authors stated that discourse analysis was among the methods or was the sole method of data analysis. The majority of the papers cluster around critical approaches to discourse analysis. Only a few approach discourse analysis primarily as analysis of conversation. Some papers are excellent, while others offer analysis that bears little resemblance to any form of discourse analysis. A strategy for improvement could include more rigorous attention on the part of those practising discourse analysis to methodology and the key features that differentiate the different approaches to discourse analysis from other qualitative methods. Authors should include sufficient detail of their approach.

  19. Prospects for Significant Theoretical Advances in Communication: The Role of the Interesting Question.

    ERIC Educational Resources Information Center

    Gouran, Dennis S.

    This paper discusses ways in which the field of speech communication can be advanced. The first half of the paper characterizes the objectivist and subjectivist views of how knowledge is acquired and the forms of inquiry to which these views have led. The remainder of the paper demonstrates the role that the "interesting question" (one for which…

  20. Advances in the understanding of host response associated with tumor PDT

    NASA Astrophysics Data System (ADS)

    Korbelik, Mladen

    2007-02-01

    Photodynamic therapy (PDT) is clinically established modality used for treatment of solid cancers and other conditions, which destroys lesions by localized generation of cytotoxic oxygen species mediated by administered drugs (photosensitizers) that are activated at targeted sites by exposure to light. Since over 20 years ago it has become increasingly clear that important contribution to the antitumor effect of PDT is secured by host reaction induced by this therapy and manifested as inflammatory and immune response. Presented is an overview of advances in the understanding of this host response associated with tumor PDT by tracing its evolution from initial breakthroughs and discoveries in the early 1980s, followed by advances preceding recent developments, and concluding with recently acquired knowledge and directions for clinical exploitation. Tribute is given to researchers making important contributions to this field during the last three decades including Drs. Gianfranco Canti, Julia Levy, and Barbara Henderson.

  1. Controlling & understanding the variables: Key to commercializing micowave processing of advanced materials

    SciTech Connect

    Garard, R.S.

    1995-12-31

    Commercial use of microwave energy for processing advanced materials has been a {open_quotes}promising new development{close_quotes} for over a decade. However, the realization of actual commercial use in most advanced material cases has not yet been achieved. As with any new processing technique, the control and application of process conditions must be reliable, repeatable, and thoroughly understood. This paper will discuss the variables associated with both economic analysis and material properties when determining the potential of microwave processing for a given application. The importance of having a microwave system capable of controlling those variables and distributing the microwave energy uniformly over large volumes within a microwave oven is reviewed. The need for a production equipment supplier to combine materials science expertise with strong microwave engineering background is also discussed with emphasis on ensuring that a good understanding of the material/microwave interaction exists for each specific application.

  2. Uncovering the Visual “Alphabet”: Advances in our understanding of object perception

    PubMed Central

    Ungerleider, Leslie G.; Bell, Andrew H.

    2011-01-01

    The ability to rapidly and accurately recognize visual stimuli represents a significant computational challenge. Yet, despite such complexity, the primate brain manages this task effortlessly. How it does so remains largely a mystery. The study of visual perception and object recognition was once limited to investigations of brain-damaged individuals or lesion experiments in animals. However, in the last 25 years, new methodologies, such as functional neuroimaging and advances in electrophysiological approaches, have provided scientists with the opportunity to examine this problem from new perspectives. This review highlights how some of these recent technological advances have contributed to the study of visual processing and where we now stand with respect to our understanding of neural mechanisms underlying object recognition. PMID:20971130

  3. Sarcasm and advanced theory of mind understanding in children and adults with prelingual deafness.

    PubMed

    O'Reilly, Karin; Peterson, Candida C; Wellman, Henry M

    2014-07-01

    Two studies addressed key theoretical debates in theory of mind (ToM) development by comparing (a) deaf native signers (n = 18), (b) deaf late signers (n = 59), and (c) age-matched hearing persons (n = 74) in childhood (Study 1: n = 81) and adulthood (Study 2: n = 70) on tests of first- and second-order false belief and conversational sarcasm. Results showed ToM development to be a life span phenomenon for deaf and hearing people alike. Native and late signers were outperformed by hearing peers on advanced ToM in childhood (M = 9 years), but in adulthood (M = 40 years), native signers had caught up, whereas late signers had not. Findings highlight the extended importance of conversational interaction for ToM growth.

  4. Understanding small biomolecule-biomaterial interactions: a review of fundamental theoretical and experimental approaches for biomolecule interactions with inorganic surfaces.

    PubMed

    Costa, Dominique; Garrain, Pierre-Alain; Baaden, Marc

    2013-04-01

    Interactions between biomolecules and inorganic surfaces play an important role in natural environments and in industry, including a wide variety of conditions: marine environment, ship hulls (fouling), water treatment, heat exchange, membrane separation, soils, mineral particles at the earth's surface, hospitals (hygiene), art and buildings (degradation and biocorrosion), paper industry (fouling) and more. To better control the first steps leading to adsorption of a biomolecule on an inorganic surface, it is mandatory to understand the adsorption mechanisms of biomolecules of several sizes at the atomic scale, that is, the nature of the chemical interaction between the biomolecule and the surface and the resulting biomolecule conformations once adsorbed at the surface. This remains a challenging and unsolved problem. Here, we review the state of art in experimental and theoretical approaches. We focus on metallic biomaterial surfaces such as TiO(2) and stainless steel, mentioning some remarkable results on hydroxyapatite. Experimental techniques include atomic force microscopy, surface plasmon resonance, quartz crystal microbalance, X-ray photoelectron spectroscopy, fluorescence microscopy, polarization modulation infrared reflection absorption spectroscopy, sum frequency generation and time of flight secondary ion mass spectroscopy. Theoretical models range from detailed quantum mechanical representations to classical forcefield-based approaches.

  5. a Roadmap to Advance Understanding of the Science of Space Weather

    NASA Astrophysics Data System (ADS)

    Schrijver, K.; Kauristie, K.; Aylward, A.; De Nardin, C. M.; Gibson, S. E.; Glover, A.; Gopalswamy, N.; Grande, M.; Hapgood, M. A.; Heynderickx, D.; Jakowski, N.; Kalegaev, V. V.; Lapenta, G.; Linker, J.; Liu, S.; Mandrini, C. H.; Mann, I. R.; Nagatsuma, T.; Nandy, D.; Obara, T.; O'Brien, T. P., III; Onsager, T. G.; Opgenoorth, H. J.; Terkildsen, M. B.; Valladares, C. E.; Vilmer, N.

    2015-12-01

    There is a growing appreciation that the environmental conditions that we call space weather impact the technological infrastructure that powers the coupled economies around the world. With that comes the need to better shield society against space weather by improving forecasts, environmental specifications, and infrastructure design. A COSPAR/ILWS team recently completed a roadmap that identifies the scientific focus areas and research infrastructure that are needed to significantly advance our understanding of space weather of all intensities and of its implications and costs for society. This presentation provides a summary of the highest-priority recommendations from that roadmap.

  6. Advances in understanding itching and scratching: a new era of targeted treatments

    PubMed Central

    Sanders, Kristen M.; Nattkemper, Leigh A.; Yosipovitch, Gil

    2016-01-01

    Chronic itch is a significant health burden with few effective treatments. As such, itch researchers seek to understand the mechanisms behind itch and to find potential targets for treatment. The field of itch research is dynamic, and many advances have been made so far this decade. In particular, major steps forward include the identification of new peripheral and central itch mediators and modulators, the discovery of greater roles for immune cells and glia in itch transmission, and a focus on the brain processing of itching and scratching. Finally, several new therapeutic interventions for itch have shown success in clinical trials. PMID:27610225

  7. USE OF COUPLED MULTI-ELECTRODE ARRAYS TO ADVANCE THE UNDERSTANDING OF SELECTED CORROSION PHENOMENA

    SciTech Connect

    N.D. Budiansky; F. Bocher; H. Cong; M.F. Hurley; J.R. Scully

    2006-02-23

    The use of multi-coupled electrode arrays in various corrosion applications is discussed with the main goal of advancing the understanding of various corrosion phenomena. Both close packed and far spaced electrode configurations are discussed. Far spaced electrode arrays are optimized for high throughput experiments capable of elucidating the effects of various variables on corrosion properties. For instance the effects of a statistical distribution of flaws on corrosion properties can be examined. Close packed arrays enable unprecedented spatial and temporal information on the behavior of local anodes and cathodes. Interactions between corrosion sites can trigger or inhibit corrosion phenomena and affect corrosion damage evolution.

  8. Advanced Reactors-Intermediate Heat Exchanger (IHX) Coupling: Theoretical Modeling and Experimental Validation

    SciTech Connect

    Utgikar, Vivek; Sun, Xiaodong; Christensen, Richard; Sabharwall, Piyush

    2016-12-29

    The overall goal of the research project was to model the behavior of the advanced reactorintermediate heat exchange system and to develop advanced control techniques for off-normal conditions. The specific objectives defined for the project were: 1. To develop the steady-state thermal hydraulic design of the intermediate heat exchanger (IHX); 2. To develop mathematical models to describe the advanced nuclear reactor-IHX-chemical process/power generation coupling during normal and off-normal operations, and to simulate models using multiphysics software; 3. To develop control strategies using genetic algorithm or neural network techniques and couple these techniques with the multiphysics software; 4. To validate the models experimentally The project objectives were accomplished by defining and executing four different tasks corresponding to these specific objectives. The first task involved selection of IHX candidates and developing steady state designs for those. The second task involved modeling of the transient and offnormal operation of the reactor-IHX system. The subsequent task dealt with the development of control strategies and involved algorithm development and simulation. The last task involved experimental validation of the thermal hydraulic performances of the two prototype heat exchangers designed and fabricated for the project at steady state and transient conditions to simulate the coupling of the reactor- IHX-process plant system. The experimental work utilized the two test facilities at The Ohio State University (OSU) including one existing High-Temperature Helium Test Facility (HTHF) and the newly developed high-temperature molten salt facility.

  9. Advances in understanding monoclonal gammopathy of undetermined significance as a precursor of multiple myeloma

    PubMed Central

    Weiss, Brendan M; Kuehl, W Michael

    2010-01-01

    Monoclonal gammopathy of undetermined significance (MGUS) affects at least 3% of the population above the age of 50 and is the precursor to multiple myeloma (MM), an incurable malignancy of plasma cells. Recent advances in MGUS include: an improved understanding of the pathogenesis of MGUS and its progression to MM, involving molecular events intrinsic to the malignant plasma cell as well as the microenvironment; novel techniques to assess risk for progression to MM using serum-free light-chain analysis and immunophenotyping; and a renewed interest in chemoprevention of MM. In the future, continued improvement in our understanding of MGUS will lead to the development of better biomarkers for prognosis and therapies for chemoprevention of MM. PMID:20473362

  10. A comparison of theoretical and experimental pressure distributions for two advanced fighter wings

    NASA Technical Reports Server (NTRS)

    Haney, H. P.; Hicks, R. M.

    1981-01-01

    A comparison was made between experimental pressure distributions measured during testing of the Vought A-7 fighter and the theoretical predictions of four transonic potential flow codes. Isolated wind and three wing-body codes were used for comparison. All comparisons are for transonic Mach numbers and include both attached and separate flows. In general, the wing-body codes gave better agreement with the experiment than did the isolated wing code but, because of the greater complexity of the geometry, were found to be considerably more expensive and less reliable.

  11. Scientific thinking in young children: theoretical advances, empirical research, and policy implications.

    PubMed

    Gopnik, Alison

    2012-09-28

    New theoretical ideas and empirical research show that very young children's learning and thinking are strikingly similar to much learning and thinking in science. Preschoolers test hypotheses against data and make causal inferences; they learn from statistics and informal experimentation, and from watching and listening to others. The mathematical framework of probabilistic models and Bayesian inference can describe this learning in precise ways. These discoveries have implications for early childhood education and policy. In particular, they suggest both that early childhood experience is extremely important and that the trend toward more structured and academic early childhood programs is misguided.

  12. Experimental Investigation and Fundamental Understanding of a Slowed UH-60A Rotor at High Advance Ratios

    NASA Technical Reports Server (NTRS)

    Datta, Anubhav; Yeo, Hyeonsoo; Norman, Thomas R.

    2011-01-01

    This paper describes and analyzes the measurements from a full-scale, slowed RPM, UH-60A rotor tested at the National Full-Scale Aerodynamics Complex 40- by 80- ft wind tunnel up to an advance ratio of 1.0. A comprehensive set of measurements, that includes performance, blade loads, hub loads and pressures/airloads makes this data set unique. The measurements reveal new and rich aeromechanical phenomena that are special to this exotic regime. These include reverse chord dynamic stall, retreating side impulse in pitch-link load, large inboard-outboard elastic twist differential, supersonic flow at low subsonic advancing tip Mach numbers, diminishing rotor forces yet dramatic build up of blade loads, and dramatic blade loads yet benign levels of vibratory hub loads. The objective of this research is the fundamental understanding of these unique aeromechanical phenomena. The intent is to provide useful knowledge for the design of high speed, high efficiency, slowed RPM rotors of the future and a challenging database for advanced analyses validation.

  13. Choroid plexus papillomas: advances in molecular biology and understanding of tumorigenesis.

    PubMed

    Safaee, Michael; Oh, Michael C; Bloch, Orin; Sun, Matthew Z; Kaur, Gurvinder; Auguste, Kurtis I; Tihan, Tarik; Parsa, Andrew T

    2013-03-01

    Choroid plexus papillomas are rare, benign tumors originating from the choroid plexus. Although generally found within the ventricular system, they can arise ectopically in the brain parenchyma or disseminate throughout the neuraxis. We sought to review recent advances in our understanding of the molecular biology and oncogenic pathways associated with this disease. A comprehensive PubMed literature review was conducted to identify manuscripts discussing the clinical, molecular, and genetic features of choroid plexus papillomas. Articles concerning diagnosis, treatment, and long-term patient outcomes were also reviewed. The introduction of atypical choroid plexus papilloma as a distinct entity has increased the need for accurate histopathologic diagnosis. Advances in immunohistochemical staining have improved our ability to differentiate choroid plexus papillomas from other intracranial tumors or metastatic lesions using combinations of key markers and mitotic indices. Recent findings have implicated Notch3 signaling, the transcription factor TWIST1, platelet-derived growth factor receptor, and the tumor necrosis factor-related apoptosis-inducing ligand pathway in choroid plexus papilloma tumorigenesis. A combination of commonly occurring chromosomal duplications and deletions has also been identified. Surgical resection remains the standard of care, although chemotherapy and radiotherapy may be considered for recurrent or metastatic lesions. While generally considered benign, these tumors possess a complex biology that sheds insight into other choroid plexus tumors, particularly malignant choroid plexus carcinomas. Improving our understanding of the molecular biology, genetics, and oncogenic pathways associated with this tumor will allow for the development of targeted therapies and improved outcomes for patients with this disease.

  14. Advances in understanding and treating liver diseases during pregnancy: A review.

    PubMed

    Kamimura, Kenya; Abe, Hiroyuki; Kawai, Hirokazu; Kamimura, Hiroteru; Kobayashi, Yuji; Nomoto, Minoru; Aoyagi, Yutaka; Terai, Shuji

    2015-05-07

    Liver disease in pregnancy is rare but pregnancy-related liver diseases may cause threat to fetal and maternal survival. It includes pre-eclampsia; eclampsia; haemolysis, elevated liver enzymes, and low platelets syndrome; acute fatty liver of pregnancy; hyperemesis gravidarum; and intrahepatic cholestasis of pregnancy. Recent basic researches have shown the various etiologies involved in this disease entity. With these advances, rapid diagnosis is essential for severe cases since the decision of immediate delivery is important for maternal and fetal survival. The other therapeutic options have also been shown in recent reports based on the clinical trials and cooperation and information sharing between hepatologist and gynecologist is important for timely therapeutic intervention. Therefore, correct understandings of diseases and differential diagnosis from the pre-existing and co-incidental liver diseases during the pregnancy will help to achieve better prognosis. Therefore, here we review and summarized recent advances in understanding the etiologies, clinical courses and management of liver disease in pregnancy. This information will contribute to physicians for diagnosis of disease and optimum management of patients.

  15. Use It or Lose It: Advances in Our Understanding of Terrestrial Nitrogen Retention and Loss (Invited)

    NASA Astrophysics Data System (ADS)

    Silver, W. L.; Yang, W. H.

    2013-12-01

    Understanding of the terrestrial nitrogen (N) cycle has grown over the last decade to include a variety of pathways that have the potential to either retain N in the ecosystem or result in losses to the atmosphere or groundwater. Early work has described the mechanics of these N transformations, but the relevance of these processes to ecosystem, regional, or global scale N cycling has not been well quantified. In this study, we review advances in our understanding of the terrestrial N cycle, and focus on three pathways with particular relevance to N retention and loss: dissimilatory nitrate and nitrite reduction to ammonium (DNRA), anaerobic ammonium oxidation (annamox), and anaerobic ammonium oxidation coupled to iron reduction (Feammox). We discuss the role of these processes in the microbial N economy (sensu Burgin et al. 2011) of the terrestrial N cycle, the environmental and ecological constraints, and relationships with other key biogeochemical cycles. We also discuss recent advances in analytical approaches that have improved our ability to detect these and related N fluxes in terrestrial ecosystems. Finally, we present a scaling exercise that identifies the potential importance of these pathways for N retention and loss across a range of spatial and temporal scales, and discuss their significance in terms of N limitation to net primary productivity, N leaching to groundwater, and the release of reactive N gases to the atmosphere.

  16. Advances in understanding and treating liver diseases during pregnancy: A review

    PubMed Central

    Kamimura, Kenya; Abe, Hiroyuki; Kawai, Hirokazu; Kamimura, Hiroteru; Kobayashi, Yuji; Nomoto, Minoru; Aoyagi, Yutaka; Terai, Shuji

    2015-01-01

    Liver disease in pregnancy is rare but pregnancy-related liver diseases may cause threat to fetal and maternal survival. It includes pre-eclampsia; eclampsia; haemolysis, elevated liver enzymes, and low platelets syndrome; acute fatty liver of pregnancy; hyperemesis gravidarum; and intrahepatic cholestasis of pregnancy. Recent basic researches have shown the various etiologies involved in this disease entity. With these advances, rapid diagnosis is essential for severe cases since the decision of immediate delivery is important for maternal and fetal survival. The other therapeutic options have also been shown in recent reports based on the clinical trials and cooperation and information sharing between hepatologist and gynecologist is important for timely therapeutic intervention. Therefore, correct understandings of diseases and differential diagnosis from the pre-existing and co-incidental liver diseases during the pregnancy will help to achieve better prognosis. Therefore, here we review and summarized recent advances in understanding the etiologies, clinical courses and management of liver disease in pregnancy. This information will contribute to physicians for diagnosis of disease and optimum management of patients. PMID:25954092

  17. Advances in Nucleon-Nucleon Scattering Experiments and Their Theoretical Consequences

    SciTech Connect

    Bekteshi, Sadik; Kabashi, Skender; Kamishi, Burim

    2007-04-23

    An overview of critical analysis of the experimental data obtained from nucleon-nucleon scattering is given and investigated in this work. Comparison of the experimental data with results of recent partial wave analysis of Nijmegen group, VPI/GWU and Saclay is given. Potentials of Nijmegen, Bonn and Argonne group are discussed. Experimental data which lead to the break of charge symmetry, to the break of the charge independence and to the determination of the off-shell tensor force, are particularly emphasized. Disagreements which exist between theoretical calculations related to the contribution of particular mechanism in different reactions are pointed out. In this relation, still open problems to be solved and measurement that should be undertaken in the future are identified, as well.

  18. Theoretical Studies of Dust in the Galactic Environment: Some Recent Advances

    NASA Technical Reports Server (NTRS)

    Leung, Chun Ming

    1995-01-01

    Dust grains, although a minor constituent, play a very important role in the thermodynamics and evolution of many astronomical objects, e.g., young and evolved stars, nebulae, interstellar clouds, and nuclei of some galaxies. Since the birth of infrared astronomy over two decades ago, significant progress has been made not only in the observations of galactic dust, but also in the theoretical studies of phenomena involving dust grains. Models with increasing degree of sophistication and physical realism (in terms of grain properties, dust formation, emission processes, and grain alignment mechanisms) have become available. Here I review recent progress made in the following areas: (1) Extinction and emission of fractal grains. (2) Dust formation in radiation-driven outflows of evolved stars. (3) Transient heating and emission of very small dust grains. Where appropriate, relevant modeling results are presented and observational implications emphasized.

  19. Recent Advances in the Theoretical Modeling of Pulsating Low-mass He-core White Dwarfs

    NASA Astrophysics Data System (ADS)

    Córsico, A. H.; Althaus, L. G.; Calcaferro, L. M.; Serenelli, A. M.; Kepler, S. O.; Jeffery, C. S.

    2017-03-01

    Many extremely low-mass (ELM) white-dwarf (WD) stars are currently being found in the field of the Milky Way. Some of these stars exhibit long-period nonradial g-mode pulsations, and constitute the class of ELMV pulsating WDs. In addition, several low-mass pre-WDs, which could be precursors of ELM WDs, have been observed to show short-period photometric variations likely due to nonradial p modes and radial modes. They could constitute a new class of pulsating low-mass pre-WD stars, the pre-ELMV stars. Here, we present the recent results of a thorough theoretical study of the nonadiabatic pulsation properties of low-mass He-core WDs and pre-WDs on the basis of fully evolutionary models representative of these stars.

  20. Fundamental Understanding of Rotor Aeromechanics at High Advance Ratio Through Wind Tunnel Testing

    NASA Astrophysics Data System (ADS)

    Berry, Benjamin

    The purpose of this research is to further the understanding of rotor aeromechanics at advance ratios (mu) beyond the maximum of 0.5 (ratio of forward airspeed to rotor tip speed) for conventional helicopters. High advance ratio rotors have applications in high speed compound helicopters. In addition to one or more conventional main rotors, these aircraft employ either thrust compounding (propellers), lift compounding (fixed-wings), or both. An articulated 4-bladed model rotor was constructed, instrumented, and tested up to a maximum advance ratio of mu=1.6 in the Glenn L. Martin Wind Tunnel at the University of Maryland. The data set includes steady and unsteady rotor hub forces and moments, blade structural loads, blade flapping angles, swashplate control angles, and unsteady blade pressures. A collective-thrust control reversal--where increasing collective pitch results in lower rotor thrust--was observed and is a unique phenomenon to the high advance ratio flight regime. The thrust reversal is explained in a physical manner as well as through an analytical formulation. The requirements for the occurrence of the thrust reversal are enumerated. The effects of rotor geometry design on the thrust reversal onset are explored through the formulation and compared to the measured data. Reverse-flow dynamic stall was observed to extend the the lifting capability of the edgewise rotor well beyond the expected static stall behavior of the airfoil sections. Through embedded unsteady blade surface pressure transducers, the normal force, pitching moment, and shed dynamic stall vortex time histories at a blade section in strong reverse flow were analyzed. Favorable comparisons with published 2-D pitching airfoil reverse flow dynamic stall data indicate that the 3-D stall environment can likely be predicted using models developed from such 2-D experiments. Vibratory hub loads were observed to increase with advance ratio. Maximum amplitude was observed near mu=1, with a

  1. Advancing Capabilities for Understanding the Earth System Through Intelligent Systems, the NSF Perspective

    NASA Astrophysics Data System (ADS)

    Gil, Y.; Zanzerkia, E. E.; Munoz-Avila, H.

    2015-12-01

    The National Science Foundation (NSF) Directorate for Geosciences (GEO) and Directorate for Computer and Information Science (CISE) acknowledge the significant scientific challenges required to understand the fundamental processes of the Earth system, within the atmospheric and geospace, Earth, ocean and polar sciences, and across those boundaries. A broad view of the opportunities and directions for GEO are described in the report "Dynamic Earth: GEO imperative and Frontiers 2015-2020." Many of the aspects of geosciences research, highlighted both in this document and other community grand challenges, pose novel problems for researchers in intelligent systems. Geosciences research will require solutions for data-intensive science, advanced computational capabilities, and transformative concepts for visualizing, using, analyzing and understanding geo phenomena and data. Opportunities for the scientific community to engage in addressing these challenges are available and being developed through NSF's portfolio of investments and activities. The NSF-wide initiative, Cyberinfrastructure Framework for 21st Century Science and Engineering (CIF21), looks to accelerate research and education through new capabilities in data, computation, software and other aspects of cyberinfrastructure. EarthCube, a joint program between GEO and the Advanced Cyberinfrastructure Division, aims to create a well-connected and facile environment to share data and knowledge in an open, transparent, and inclusive manner, thus accelerating our ability to understand and predict the Earth system. EarthCube's mission opens an opportunity for collaborative research on novel information systems enhancing and supporting geosciences research efforts. NSF encourages true, collaborative partnerships between scientists in computer sciences and the geosciences to meet these challenges.

  2. Turner syndrome: advances in understanding altered cognition, brain structure and function.

    PubMed

    Knickmeyer, Rebecca C

    2012-04-01

    Turner syndrome, which results from the complete or partial loss of a sex chromosome, is associated with a particular pattern of cognitive impairments and strengths and an increased risk for specific neurodevelopmental disorders. This review highlights recent progress in understanding brain structure and function in Turner syndrome and identifies several critical research needs. Recent work on social cognition in Turner syndrome has identified a range of difficulties despite a maintained social appetite, a disconnect which could result in distress for affected individuals. Progress has been made in identifying foundational deficits in attention and executive function that could explain visual-spatial and arithmetical impairments. Neuroimaging studies have advanced our understanding of brain development and function through the application of cutting edge analysis techniques. Haploinsufficiency of genes, failure to express parentally imprinted genes, uncovering of X chromosome mutations, and gonadal steroid deficiency may all contribute to altered brain development, but additional work is required to link specific mechanisms to specific phenotypes. Also needed are studies of interventions to assist individuals with Turner syndrome in visual-spatial, mathematical, and social skills. Ultimately a better understanding of brain structure and function in Turner syndrome will generate new therapeutic approaches for this population.

  3. Advancing our understanding of functional genome organisation through studies in the fission yeast.

    PubMed

    Olsson, Ida; Bjerling, Pernilla

    2011-02-01

    Significant progress has been made in understanding the functional organisation of the cell nucleus. Still many questions remain to be answered about the relationship between the spatial organisation of the nucleus and the regulation of the genome function. There are many conflicting data in the field making it very difficult to merge published results on mammalian cells into one model on subnuclear chromatin organisation. The fission yeast, Schizosaccharomyces pombe, over the last decades has emerged as a valuable model organism in understanding basic biological mechanisms, especially the cell cycle and chromosome biology. In this review we describe and compare the nuclear organisation in mammalian and fission yeast cells. We believe that fission yeast is a good tool to resolve at least some of the contradictions and unanswered questions concerning functional nuclear architecture, since S. pombe has chromosomes structurally similar to that of human. S. pombe also has the advantage over higher eukaryotes in that the genome can easily be manipulated via homologous recombination making it possible to integrate the tools needed for visualisation of chromosomes using live-cell microscopy. Classical genetic experiments can be used to elucidate what factors are involved in a certain mechanism. The knowledge we have gained during the last few years indicates similarities between the genome organisation in fission yeast and mammalian cells. We therefore propose the use of fission yeast for further advancement of our understanding of functional nuclear organisation.

  4. Understanding

    ERIC Educational Resources Information Center

    Buxkemper, Andra C.; Hartfiel, D. J.

    2003-01-01

    There is no common agreement on the meaning of the word "understand". However, there is agreement on what students should be able to do with material they understand. Bloom et al. discuss kinds of tasks a student should be able to do, provided that the student understands. In a similar way, Biggs and Collis provide a taxonomy intended to evaluate…

  5. A theoretical understanding on the CO-tolerance mechanism of the WC(0001) supported Pt monolayer: Some improvement strategies

    NASA Astrophysics Data System (ADS)

    Zhang, Xilin; Lu, Zhansheng; Yang, Zongxian

    2016-12-01

    The deposition of platinum on the tungsten carbide (Pt/WC) have been achieved and proved with high stability, activity and CO-tolerance toward some reactions in experiments. Although a lot of experimental efforts have been focused on understanding the activity, stability and CO-tolerance of Pt/WC, the relevant theoretical works related to the CO-tolerance mechanism are still scarce. In current study, the adsorption and oxidation of CO on the Pt monolayer supported on WC(0001) surface (PtML/WC(0001)) are investigated using density functional theory calculations. It is found that the oxidation of CO on PtML/WC(0001) proceeds preferably along the Langmuir-Hinshelwood mechanism. The energy barrier of 1.06 eV for the rate-determining step of OOCO formation is almost equal to that (1.05 eV) for CO oxidation by atomic O on Pt(111), while the adsorption energy of 1.59 eV for CO on PtML/WC(0001) is smaller than that on Pt(111) (1.85 eV), indicating that the high resistance to CO poisoning of PtML/WC(0001) may originate from the weak interaction between them. To further improve the CO tolerance, some probable strategies are proposed based on the relevant kinetics results. The current results are helpful to understanding the origin of the highly resistant to CO poisoning of PtML/WC(0001) and rationally designing catalysts to improve the CO oxidation activity.

  6. Mundane science use in a practice theoretical perspective: Different understandings of the relations between citizen-consumers and public communication initiatives build on scientific claims.

    PubMed

    Halkier, Bente

    2015-08-13

    Public communication initiatives play a part in placing complicated scientific claims in citizen-consumers' everyday contexts. Lay reactions to scientific claims framed in public communication, and attempts to engage citizens, have been important subjects of discussion in the literatures of public understanding and public engagement with science. Many of the public communication initiatives, however, address lay people as consumers rather than citizens. This creates specific challenges for understanding public engagement with science and scientific citizenship. The article compares five different understandings of the relations between citizen-consumers and public issue communication involving science, where the first four types are widely represented in the Public Understanding of Science discussions. The fifth understanding is a practice theoretical perspective. The article suggests how the public understanding of and engagement in science literature can benefit from including a practice theoretical approach to research about mundane science use and public engagement.

  7. Significance of weak interactions in imidazolium picrate ionic liquids: spectroscopic and theoretical studies for molecular level understanding.

    PubMed

    Panja, Sumit Kumar; Dwivedi, Nidhi; Noothalapati, Hemanth; Shigeto, Shinsuke; Sikder, A K; Saha, Abhijit; Sunkari, Sailaja S; Saha, Satyen

    2015-07-21

    The effects of interionic hydrogen bonding and π-π stacking interactions on the physical properties of a new series of picrate anion based ionic liquids (ILs) have been investigated experimentally and theoretically. The existence of aromatic (C2-HO) and aliphatic (C7-HO-N22 and C6-HO-N20) hydrogen bonding and π-π stacking interactions in these ILs has been observed using various spectroscopic techniques. The aromatic and aliphatic C-HO hydrogen bonding interactions are found to have a crucial role in binding the imidazolium cation and picrate anion together. However, the π-π stacking interactions between two successive layers are found to play a decisive role in tight packing in ILs leading to differences in physical properties. The drastic difference in the melting points of the methyl and propyl derivatives (mmimPic and pmimPic respectively) have been found to be primarily due to the difference in the strength and varieties of π-π stacking interactions. While in mmimPic, several different types of π-π stacking interactions between the aromatic rings (such as picrate-picrate, picrate-imidazole and imidazolium-imidazolium cation rings) are observed, only one type of π-π stacking interaction (picrate-picrate rings) is found to exist in the pmimPic IL. NMR spectroscopic studies reveal that the interaction of these ILs with solvent molecules is different and depends on the dielectric constant of the solvent. While an ion solvation model explains the solvation in high dielectric solvents, an ion-pair solvation model is found to be more appropriate for low dielectric constant solvents. The enhanced stability of these investigated picrate ILs compared with that of inorganic picrate salts under high doses of γ radiation clearly indicates the importance of weak interionic interactions in ILs, and also opens up the possibility of the application of picrate ILs as prospective diluents in nuclear separation for advanced fuel cycling process.

  8. Strategizing Safety: Theoretical Frameworks to Understand Women's Decision Making in the Face of Partner Violence and Social Inequities.

    PubMed

    Velonis, Alisa J; Daoud, Nihaya; Matheson, Flora; Woodhall-Melnik, Julia; Hamilton-Wright, Sarah; O'Campo, Patricia

    2015-08-24

    Women in physically and psychologically abusive relationships face numerous decisions related to their safety: decisions that historically have been viewed by researchers and human service practitioners as related to individual or interpersonal factors, such as how they feel about their partner, what they (or those they are close to) think is best for their children, or whether they have a safe place to go to. Social and structural factors, such as poverty, sexism, and barriers related to disability, are either left out or viewed at their individual-level consequence, such as a woman's employment status. Using interview data and case studies from a larger study on housing instability, partner violence, and health, the authors apply ecological and macro-level theoretical models that go beyond the individual level to the stories of women who struggled with partner violence, arguing that it is critical to examine the large social and structural forces that impact women's lives if we are to understand the decisions women make when facing a violent partner.

  9. The critical perspective in psychological jurisprudence theoretical advances and epistemological assumptions.

    PubMed

    Arrigo, Bruce A

    2002-01-01

    The critical perspectives of psychological jurisprudence identified above, along with their corresponding epistemological assumptions, reflect a radical agenda for change at the law-psychology divide. Although not exhaustively reviewed, the individual theories represent different approaches by which structural reform can be enacted and citizen well-being can therefore be realized. Collectively, the critical perspectives and their attending presuppositions challenge conventional wisdom about prospects for transforming (i.e., humanizing) the legal apparatus. I submit that the future viability of the law-psychology movement, and its overall utility for society, considerably depends on its capacity to facilitate and secure such widespread change. By focusing on critical theoretical inquiry, this article makes painfully clear that much of what is wrong with the legal system, especially in its interactions with and interpretations of people, cannot be amended or solved through it. Indeed, as Roesch (1995) observed, "changes in the justice system will never be sufficient to create a just society, nor will within system changes by themselves ever have much of an impact on individuals who come into conflict with the law" (p. 3). I agree. Accordingly, it is time to move on and, where necessary, to look elsewhere for guidance. The radical agenda in psychological jurisprudence represents a provocative strategy, providing a meaningful basis for critique and a sustainable basis for reform. Both are integral to the call for justice embodied in the founding of the AP-LS decades ago. Realizing this challenge, however, remains an unfulfilled dream. Thus, the task that awaits is to apply the insights of critical psychological jurisprudence to relevant areas of research and policy. I submit that the academy can ill afford to dismiss this task. Indeed, in the final analysis, to do so would not only defer prospects for justice but would destroy its very possibility, especially for

  10. Advances in understanding the molecular basis of the first steps in color vision.

    PubMed

    Hofmann, Lukas; Palczewski, Krzysztof

    2015-11-01

    Serving as one of our primary environmental inputs, vision is the most sophisticated sensory system in humans. Here, we present recent findings derived from energetics, genetics and physiology that provide a more advanced understanding of color perception in mammals. Energetics of cis-trans isomerization of 11-cis-retinal accounts for color perception in the narrow region of the electromagnetic spectrum and how human eyes can absorb light in the near infrared (IR) range. Structural homology models of visual pigments reveal complex interactions of the protein moieties with the light sensitive chromophore 11-cis-retinal and that certain color blinding mutations impair secondary structural elements of these G protein-coupled receptors (GPCRs). Finally, we identify unsolved critical aspects of color tuning that require future investigation. Copyright © 2015. Published by Elsevier Ltd.

  11. Advances in understanding the molecular basis of the first steps in color vision

    PubMed Central

    Hofmann, Lukas; Palczewski, Krzysztof

    2015-01-01

    Serving as one of our primary environmental inputs, vision is the most sophisticated sensory system in humans. Here, we present recent findings derived from energetics, genetics and physiology that provide a more advanced understanding of color perception in mammals. Energetics of cis–trans isomerization of 11-cis-retinal accounts for color perception in the narrow region of the electromagnetic spectrum and how human eyes can absorb light in the near infrared (IR) range. Structural homology models of visual pigments reveal complex interactions of the protein moieties with the light sensitive chromophore 11-cis-retinal and that certain color blinding mutations impair secondary structural elements of these G protein-coupled receptors (GPCRs). Finally, we identify unsolved critical aspects of color tuning that require future investigation. PMID:26187035

  12. [Advances in understanding Drosophila salivary gland polytene chromosome and its applications in genetics teaching].

    PubMed

    Gang, Li; Fanguo, Chen

    2015-06-01

    Drosophila salivary gland polytene chromosome, one of the three classical chromosomes with remarkable characteristics, has been used as an outstanding model for a variety of genetic studies since 1934. The greatest contribution of this model to genetics has been providing extraordinary angle of view in studying interphase chromosome structure and gene expression regulation. Additionally, it has been extensively used to understand some special genetic phenomena, such as dosage compensation and position-effect variegation. In this paper, we briefly review the advances in the study of Drosophila salivary gland chromosome, and try to systematically and effectively introduce this model system into genetics teaching practice in order to steer and inspire students' interest in genetics.

  13. Advancing understanding of microbial bioenergy conversion processes by activity-based protein profiling

    SciTech Connect

    Liu, Yun; Fredrickson, James K.; Sadler, Natalie C.; Nandhikonda, Premchendar; Smith, Richard D.; Wright, Aaron T.

    2015-09-25

    Here, the development of renewable biofuels is a global priority, but success will require novel technologies that greatly improve our understanding of microbial systems biology. An approach with great promise in enabling functional characterization of microbes is activity-based protein profiling (ABPP), which employs chemical probes to directly measure enzyme function in discrete enzyme classes in vivo and/or in vitro, thereby facilitating the rapid discovery of new biocatalysts and enabling much improved biofuel production platforms. We review general design strategies in ABPP, and highlight recent advances that are or could be pivotal to biofuels processes including applications of ABPP to cellulosic bioethanol, biodiesel, and phototrophic production of hydrocarbons. We also examine the key challenges and opportunities of ABPP in renewable biofuels research. The integration of ABPP with molecular and systems biology approaches will shed new insight on the catalytic and regulatory mechanisms of functional enzymes and their synergistic effects in the field of biofuels production.

  14. Understanding of advance care planning by family members of persons undergoing hemodialysis.

    PubMed

    Calvin, Amy O; Engebretson, Joan C; Sardual, S Alexander

    2014-11-01

    The purpose of this qualitative descriptive study was to explore hemodialysis patients' family members' understanding of end-of-life decision-making processes. The project aimed to address (a) family members' constructions of advance care planning (ACP), including their roles and responsibilities, and (b) family members' perceptions of health care providers' roles and responsibilities in ACP. Eighteen family members of persons undergoing hemodialysis were recruited primarily from outpatient dialysis facilities and interviewed individually. Confirmed transcript data were analyzed, coded, and compared, and categories were established. Interpretations were validated throughout the interviews and peer debriefing sessions were used at a later stage in the analysis. The overarching construct identified was one of Protection. Family members protect patients by (a) Sharing Burdens, (b) Normalizing Life, and (c) Personalizing Care. Recommendations for future research include the need to explore ACP of persons undergoing hemodialysis who do not have a family support system. © The Author(s) 2013.

  15. Understanding requirements of novel healthcare information systems for management of advanced prostate cancer.

    PubMed

    Wagholikar, Amol S; Fung, Maggie; Nelson, Colleen C

    2012-01-01

    Effective management of chronic diseases is a global health priority. A healthcare information system offers opportunities to address challenges of chronic disease management. However, the requirements of health information systems are often not well understood. The accuracy of requirements has a direct impact on the successful design and implementation of a health information system. Our research describes methods used to understand the requirements of health information systems for advanced prostate cancer management. The research conducted a survey to identify heterogeneous sources of clinical records. Our research showed that the General Practitioner was the common source of patient's clinical records (41%) followed by the Urologist (14%) and other clinicians (14%). Our research describes a method to identify diverse data sources and proposes a novel patient journey browser prototype that integrates disparate data sources.

  16. Understanding patients' and doctors' attitudes about shared decision making for advance care planning.

    PubMed

    Hajizadeh, Negin; Uhler, Lauren M; Pérez Figueroa, Rafael E

    2015-12-01

    Although shared decision making (SDM) is the preferred model of making complex treatment decisions with patients, patients' and doctors' attitudes towards SDM for advance care planning are unknown. We sought to: (i) gain general insights into the current practice of SDM and attitudes about patient involvement, and (ii) gain specific insights into experience with, and attitudes about, SDM for advance care planning. Qualitative analysis of face-to-face semi-structured interviews. Patients with chronic lung disease and their doctors at a New York City public hospital. Although patients described participation in decision making, many deferred the final decision to their doctors. Doctors indicated a preference for SDM but expressed barriers including perceived lack of patient understanding and lack of patient empowerment. With regard to end-of-life discussions, patients were generally open to having these discussions with their doctors, although their openness sometimes depended on the circumstance (i.e. end-of-life discussions may be more acceptable to patients for whom the chance of dying is high). Doctors reported engaging in end-of-life treatment decisions with their patients, although expressed the need for conversations to take place earlier, in advance of acute illness, and identified a lack of prognostic estimates as one barrier to engaging in this discussion. Doctors should explore their patients' attitudes regarding end-of-life discussions and preferences for decision-making styles. There is a need for tools such as decision aids which can empower patients to participate in decision making and can support doctors with prognostic estimates pertinent to individual patients. © 2014 The Authors Health Expectations Published by John Wiley & Sons Ltd.

  17. Understanding how cancer patients actualise, relinquish, and reject advance care planning: implications for practice.

    PubMed

    Michael, Natasha; O'Callaghan, Clare; Clayton, Josephine; Pollard, Annabel; Stepanov, Nikola; Spruyt, Odette; Michael, Michael; Ball, David

    2013-08-01

    Although advance care planning (ACP) is recognised as integral to quality cancer care, it remains poorly integrated in many settings. Given cancer patients' unpredictable disease trajectories and equivocal treatment options, a disease-specific ACP model may be necessary. This study examines how Australian cancer patients consider ACP. Responses will inform the development of an Australian Cancer Centre's ACP programme. A constructivist research approach with grounded theory design was applied. Eighteen adults from lung and gastro-intestinal tumour streams participated. Participants first described their initial understanding of ACP, received ACP information, and finally completed a semi-structured interview assisted by the vignette technique. Qualitative inter-rater reliability was integrated. Participants initially had scant knowledge of ACP. On obtaining further information, their responses indicated that: For cancer patients, ACP is an individualised, dynamic, and shared process characterised by myriad variations in choices to actualise, relinquish, and/or reject its individual components (medical enduring power of attorney, statement of choices, refusal of treatment certificate, and advanced directive). Actualisation of each component involves considering, possibly conversing about, planning, and communicating a decision, usually iteratively. Reactions can change over time and are informed by values, memories, personalities, health perceptions, appreciation of prognoses, and trust or doubts in their substitute decision makers. Findings endorse the value of routinely, though sensitively, discussing ACP with cancer patients at various time points across their disease trajectory. Nonetheless, ACP may also be relinquished or rejected and ongoing offers for ACP in some patients may be offensive to their value system.

  18. Recent advances in understanding the role of the hypothalamic circuit during aggression

    PubMed Central

    Falkner, Annegret L.; Lin, Dayu

    2014-01-01

    The hypothalamus was first implicated in the classic “fight or flight” response nearly a century ago, and since then, many important strides have been made in understanding both the circuitry and the neural dynamics underlying the generation of these behaviors. In this review, we will focus on the role of the hypothalamus in aggression, paying particular attention to recent advances in the field that have allowed for functional identification of relevant hypothalamic subnuclei. Recent progress in this field has been aided by the development of new techniques for functional manipulation including optogenetics and pharmacogenetics, as well as advances in technology used for chronic in vivo recordings during complex social behaviors. We will examine the role of the hypothalamus through the complimentary lenses of (1) loss of function studies, including pharmacology and pharmacogenetics; (2) gain of function studies, including specific comparisons between results from classic electrical stimulation studies and more recent work using optogenetics; and (3) neural activity, including both immediate early gene and awake-behaving recordings. Lastly, we will outline current approaches to identifying the precise role of the hypothalamus in promoting aggressive motivation and aggressive action. PMID:25309351

  19. New understanding of rhizosphere processes enabled by advances in molecular and spatially resolved techniques

    DOE PAGES

    Hess, Nancy J.; Pasa-Tolic, Ljiljana; Bailey, Vanessa L.; ...

    2017-04-12

    Understanding the role played by microorganisms within soil systems is challenged by the unique intersection of physics, chemistry, mineralogy and biology in fostering habitat for soil microbial communities. To address these challenges will require observations across multiple spatial and temporal scales to capture the dynamics and emergent behavior from complex and interdependent processes. The heterogeneity and complexity of the rhizosphere require advanced techniques that press the simultaneous frontiers of spatial resolution, analyte sensitivity and specificity, reproducibility, large dynamic range, and high throughput. Fortunately many exciting technical advancements are now available to inform and guide the development of new hypotheses. Themore » aim of this Special issue is to provide a holistic view of the rhizosphere in the perspective of modern molecular biology methodologies that enabled a highly-focused, detailed view on the processes in the rhizosphere, including numerous, strong and complex interactions between plant roots, soil constituents and microorganisms. We discuss the current rhizosphere research challenges and knowledge gaps, as well as perspectives and approaches using newly available state-of-the-art toolboxes. These new approaches and methodologies allow the study of rhizosphere processes and properties, and rhizosphere as a central component of ecosystems and biogeochemical cycles.« less

  20. Advanced MRI techniques to improve our understanding of experience-induced neuroplasticity.

    PubMed

    Tardif, Christine Lucas; Gauthier, Claudine Joëlle; Steele, Christopher John; Bazin, Pierre-Louis; Schäfer, Andreas; Schaefer, Alexander; Turner, Robert; Villringer, Arno

    2016-05-01

    Over the last two decades, numerous human MRI studies of neuroplasticity have shown compelling evidence for extensive and rapid experience-induced brain plasticity in vivo. To date, most of these studies have consisted of simply detecting a difference in structural or functional images with little concern for their lack of biological specificity. Recent reviews and public debates have stressed the need for advanced imaging techniques to gain a better understanding of the nature of these differences - characterizing their extent in time and space, their underlying biological and network dynamics. The purpose of this article is to give an overview of advanced imaging techniques for an audience of cognitive neuroscientists that can assist them in the design and interpretation of future MRI studies of neuroplasticity. The review encompasses MRI methods that probe the morphology, microstructure, function, and connectivity of the brain with improved specificity. We underline the possible physiological underpinnings of these techniques and their recent applications within the framework of learning- and experience-induced plasticity in healthy adults. Finally, we discuss the advantages of a multi-modal approach to gain a more nuanced and comprehensive description of the process of learning. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Advances in Understanding of Swift Heavy-Ion Tracks in Complex Ceramics

    SciTech Connect

    Lang, Maik; Devanathan, Ram; Toulemonde, Marcel; Trautmann, Christina

    2015-02-01

    Tracks produced by swift heavy ions in ceramics are of interest for fundamental science as well as for applications covering different fields such as nanotechnology or fission-track dating of minerals. In the case of pyrochlores with general formula A2B2O7, the track structure and radiation sensitivity shows a clear dependence on the composition. Ion irradiated Gd2Zr2O7, e.g., retains its crystallinity while amorphous tracks are produced in Gd2Ti2O7. Tracks in Ti-containing compositions have a complex morphology consisting of an amorphous core surrounded by a shell of a disordered, defect-fluorite phase. The size of the amorphous core decreases with decreasing energy loss and with increasing Zr content, while the shell thickness seems to be similar over a wide range of energy loss values. The large data set and the complex track structure has made pyrochlore an interesting model system for a general theoretical description of track formation including thermal spike calculations (providing the spatial and temporal evolution of temperature around the ion trajectory) and molecular dynamics (MD) simulations (describing the response of the atomic system).Recent MD advances consider the sudden temperature increase by inserting data from the thermal spike. The combination allows the reproduction of the core-shell track characteristic and sheds light on the early stages of track formation including recrystallization of the molten material produced by the thermal spike.

  2. Research and development program for the development of advanced time-temperature dependent constitutive relationships. Volume 1: Theoretical discussion

    NASA Technical Reports Server (NTRS)

    Cassenti, B. N.

    1983-01-01

    The results of a 10-month research and development program for the development of advanced time-temperature constitutive relationships are presented. The program included (1) the effect of rate of change of temperature, (2) the development of a term to include time independent effects, and (3) improvements in computational efficiency. It was shown that rate of change of temperature could have a substantial effect on the predicted material response. A modification to include time-independent effects, applicable to many viscoplastic constitutive theories, was shown to reduce to classical plasticity. The computation time can be reduced by a factor of two if self-adaptive integration is used when compared to an integration using ordinary forward differences. During the course of the investigation, it was demonstrated that the most important single factor affecting the theoretical accuracy was the choice of material parameters.

  3. Recent advances in theoretical and numerical studies of wire array Z-pinch in the IAPCM

    NASA Astrophysics Data System (ADS)

    Ding, Ning; Zhang, Yang; Xiao, Delong; Wu, Jiming; Huang, Jun; Yin, Li; Sun, Shunkai; Xue, Chuang; Dai, Zihuan; Ning, Cheng; Shu, Xiaojian; Wang, Jianguo; Li, Hua

    2014-12-01

    Fast Z-pinch has produced the most powerful X-ray radiation source in laboratory and also shows the possibility to drive inertial confinement fusion (ICF). Recent advances in wire-array Z-pinch researches at the Institute of Applied Physics and Computational Mathematics are presented in this paper. A typical wire array Z-pinch process has three phases: wire plasma formation and ablation, implosion and the MRT instability development, stagnation and radiation. A mass injection model with azimuthal modulation coefficient is used to describe the wire initiation, and the dynamics of ablated plasmas of wire-array Z-pinches in (r, θ) geometry is numerically studied. In the implosion phase, a two-dimensional(r, z) three temperature radiation MHD code MARED has been developed to investigate the development of the Magneto-Rayleigh-Taylor(MRT) instability. We also analyze the implosion modes of nested wire-array and find that the inner wire-array is hardly affected before the impaction of the outer wire-array. While the plasma accelerated to high speed in the implosion stage stagnates on the axis, abundant x-ray radiation is produced. The energy spectrum of the radiation and the production mechanism are investigated. The computational x-ray pulse shows a reasonable agreement with the experimental result. We also suggest that using alloyed wire-arrays can increase multi-keV K-shell yield by decreasing the opacity of K-shell lines. In addition, we use a detailed circuit model to study the energy coupling between the generator and the Z-pinch implosion. Recently, we are concentrating on the problems of Z-pinch driven ICF, such as dynamic hohlraum and capsule implosions. Our numerical investigations on the interaction of wire-array Z-pinches on foam convertors show qualitative agreements with experimental results on the "Qiangguang I" facility. An integrated two-dimensional simulation of dynamic hohlraum driven capsule implosion provides us the physical insights of wire

  4. Recent advances in theoretical and numerical studies of wire array Z-pinch in the IAPCM

    SciTech Connect

    Ding, Ning Zhang, Yang Xiao, Delong Wu, Jiming Huang, Jun Yin, Li Sun, Shunkai Xue, Chuang Dai, Zihuan Ning, Cheng Shu, Xiaojian Wang, Jianguo Li, Hua

    2014-12-15

    Fast Z-pinch has produced the most powerful X-ray radiation source in laboratory and also shows the possibility to drive inertial confinement fusion (ICF). Recent advances in wire-array Z-pinch researches at the Institute of Applied Physics and Computational Mathematics are presented in this paper. A typical wire array Z-pinch process has three phases: wire plasma formation and ablation, implosion and the MRT instability development, stagnation and radiation. A mass injection model with azimuthal modulation coefficient is used to describe the wire initiation, and the dynamics of ablated plasmas of wire-array Z-pinches in (r, θ) geometry is numerically studied. In the implosion phase, a two-dimensional(r, z) three temperature radiation MHD code MARED has been developed to investigate the development of the Magneto-Rayleigh-Taylor(MRT) instability. We also analyze the implosion modes of nested wire-array and find that the inner wire-array is hardly affected before the impaction of the outer wire-array. While the plasma accelerated to high speed in the implosion stage stagnates on the axis, abundant x-ray radiation is produced. The energy spectrum of the radiation and the production mechanism are investigated. The computational x-ray pulse shows a reasonable agreement with the experimental result. We also suggest that using alloyed wire-arrays can increase multi-keV K-shell yield by decreasing the opacity of K-shell lines. In addition, we use a detailed circuit model to study the energy coupling between the generator and the Z-pinch implosion. Recently, we are concentrating on the problems of Z-pinch driven ICF, such as dynamic hohlraum and capsule implosions. Our numerical investigations on the interaction of wire-array Z-pinches on foam convertors show qualitative agreements with experimental results on the “Qiangguang I” facility. An integrated two-dimensional simulation of dynamic hohlraum driven capsule implosion provides us the physical insights of wire

  5. From evidence to understanding: a commentary on Fisher (1922) ‘On the mathematical foundations of theoretical statistics’

    PubMed Central

    Hand, David J.

    2015-01-01

    The nature of statistics has changed over time. It was originally concerned with descriptive ‘matters of state’—with summarizing population numbers, economic strength and social conditions. But during the course of the twentieth century its aim broadened to include inference—how to use data to shed light on underlying mechanisms, about what might happen in the future, about what would happen if certain actions were taken. Central to this development was Ronald Fisher. Over the course of his life he was responsible for many of the major conceptual advances in statistics. This is particularly illustrated by his 1922 paper, in which he introduced many of the concepts which remain fundamental to our understanding of how to extract meaning from data, right to the present day. It is no exaggeration to say that Fisher's work, as illustrated by the ideas he described and developed in this paper, underlies all modern science, and much more besides. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750151

  6. Recent advances in understanding the biology, epidemiology and control of chlamydial infections in koalas.

    PubMed

    Polkinghorne, Adam; Hanger, Jon; Timms, Peter

    2013-08-30

    The koala (Phascolarctos cinereus) is recognised as a threatened wildlife species in various parts of Australia. A major contributing factor to the decline and long-term viability of affected populations is disease caused by the obligate intracellular bacteria, Chlamydia. Two chlamydial species infect the koala, Chlamydia pecorum and Chlamydia pneumoniae, and have been reported in nearly all mainland koala populations. Chlamydial infections of koalas are associated with ocular infections leading to blindness and genital tract infections linked to infertility, among other serious clinical manifestations. Diagnosis can be based on clinical presentation alone, however, it is complicated by the observation that many koala chlamydial infections occur with no overt signs of clinical disease. Instead, accurate diagnosis requires detailed clinical assessment and confirmatory testing by a range of PCR-based assays. Antibiotic treatment for koala chlamydial infection is possible, however, results on its success are mixed. A more practical solution for the protection of diseased populations is the application of a koala Chlamydia vaccine, with recent trials indicating promising results. Interestingly, molecular epidemiology studies of koala C. pecorum infections and recent comparative genomic analyses of koala C. pneumoniae have revealed potential differences in their origin that will have wider ramifications for our understanding of human chlamydial infections and host adaptation of the chlamydiae. This review summarises changes to the taxonomy of koala chlamydial infections and recent advances in our understanding of the epidemiology, diagnosis, treatment, control and evolution of Chlamydia infections in this iconic wildlife species. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Recent advances in understanding hypertension development in sub-Saharan Africa.

    PubMed

    Schutte, A E; Botha, S; Fourie, C M T; Gafane-Matemane, L F; Kruger, R; Lammertyn, L; Malan, L; Mels, C M C; Schutte, R; Smith, W; van Rooyen, J M; Ware, L J; Huisman, H W

    2017-03-23

    Consistent reports indicate that hypertension is a particularly common finding in black populations. Hypertension occurs at younger ages and is often more severe in terms of blood pressure levels and organ damage than in whites, resulting in a higher incidence of cardiovascular disease and mortality. This review provides an outline of recent advances in the pathophysiological understanding of blood pressure elevation and the consequences thereof in black populations in Africa. This is set against the backdrop of populations undergoing demanding and rapid demographic transition, where infection with the human immunodeficiency virus predominates, and where under and over-nutrition coexist. Collectively, recent findings from Africa illustrate an increased lifetime risk to hypertension from foetal life onwards. From young ages black populations display early endothelial dysfunction, increased vascular tone and reactivity, microvascular structural adaptions as well as increased aortic stiffness resulting in elevated central and brachial blood pressures during the day and night, when compared to whites. Together with knowledge on the contributions of sympathetic activation and abnormal renal sodium handling, these pathophysiological adaptations result in subclinical and clinical organ damage at younger ages. This overall enhanced understanding on the determinants of blood pressure elevation in blacks encourages (a) novel approaches to assess and manage hypertension in Africa better, (b) further scientific discovery to develop more effective prevention and treatment strategies and

  8. Advances in understanding tumour evolution through single-cell sequencing.

    PubMed

    Kuipers, Jack; Jahn, Katharina; Beerenwinkel, Niko

    2017-02-11

    The mutational heterogeneity observed within tumours poses additional challenges to the development of effective cancer treatments. A thorough understanding of a tumour's subclonal composition and its mutational history is essential to open up the design of treatments tailored to individual patients. Comparative studies on a large number of tumours permit the identification of mutational patterns which may refine forecasts of cancer progression, response to treatment and metastatic potential. The composition of tumours is shaped by evolutionary processes. Recent advances in next-generation sequencing offer the possibility to analyse the evolutionary history and accompanying heterogeneity of tumours at an unprecedented resolution, by sequencing single cells. New computational challenges arise when moving from bulk to single-cell sequencing data, leading to the development of novel modelling frameworks. In this review, we present the state of the art methods for understanding the phylogeny encoded in bulk or single-cell sequencing data, and highlight future directions for developing more comprehensive and informative pictures of tumour evolution. This article is part of a Special Issue entitled: Evolutionary principles - heterogeneity in cancer?, edited by Dr. Robert A. Gatenby.

  9. Understanding the physical and chemical nature of the warfarin drug binding site in human serum albumin: experimental and theoretical studies.

    PubMed

    Abou-Zied, Osama K

    2015-01-01

    Human serum albumin (HSA) is one of the major carrier proteins in the body and constitutes approximately half of the protein found in blood plasma. It plays an important role in lipid metabolism, and its ability to reversibly bind a large variety of pharmaceutical compounds makes it a crucial determinant of drug pharmacokinetics and pharmacodynamics. This review deals with one of the protein's major binding sites "Sudlow I" which includes a binding pocket for the drug warfarin (WAR). The binding nature of this important site can be characterized by measuring the spectroscopic changes when a ligand is bound. Using several drugs, including WAR, and other drug-like molecules as ligands, the results emphasize the nature of Sudlow I as a flexible binding site, capable of binding a variety of ligands by adapting its binding pockets. The high affinity of the WAR pocket for binding versatile molecular structures stems from the flexibility of the amino acids forming the pocket. The binding site is shown to have an ionization ability which is important to consider when using drugs that are known to bind in Sudlow I. Several studies point to the important role of water molecules trapped inside the binding site in molecular recognition and ligand binding. Water inside the protein's cavity is crucial in maintaining the balance between the hydrophobic and hydrophilic nature of the binding site. Upon the unfolding and refolding of HSA, more water molecules are trapped inside the binding site which cause some swelling that prevents a full recovery from the denatured state. Better understanding of the mechanism of binding in macromolecules such as HSA and other proteins can be achieved by combining experimental and theoretical studies which produce significant synergies in studying complex biochemical phenomena.

  10. Towards a Theoretical Framework for the Comparative Understanding of Globalisation, Higher Education, the Labour Market and Inequality

    ERIC Educational Resources Information Center

    Kupfer, Antonia

    2011-01-01

    This paper is a theoretical examination of three major empirical trends that affect many people: globalisation, increasingly close relations between higher education (HE) and labour markets, and increasing social inequality. Its aim is to identify key theoretical resources and their contribution to the development of a comparative theoretical…

  11. Towards a Theoretical Framework for the Comparative Understanding of Globalisation, Higher Education, the Labour Market and Inequality

    ERIC Educational Resources Information Center

    Kupfer, Antonia

    2011-01-01

    This paper is a theoretical examination of three major empirical trends that affect many people: globalisation, increasingly close relations between higher education (HE) and labour markets, and increasing social inequality. Its aim is to identify key theoretical resources and their contribution to the development of a comparative theoretical…

  12. Advances in understanding of soil biogeochemical cycles: the mechanism of HS entry into the root interior

    NASA Astrophysics Data System (ADS)

    Aleksandrova, Olga

    2017-04-01

    Humic substances represent the major reservoir of carbon (C) in ecosystems, and their turnover is crucial for understanding the global C cycle. As shown by some investigators [1-2], the phenomenon of the uptake of the whole humic particles by plant roots is a significant step of biogeochemical cycle of carbon in soils. The mechanism of HS entry the root interior remained unknown for a long time. However recently, the last one was discovered [3]. An advanced model [3] includes two hypotheses. These hypotheses are as follows: (1) each nano-size particle possesses a quantum image that can be revealed as a packet of electromagnetic waves; (2) the interaction of nano-size particle with the membrane (plasma membrane) of living cells, on which it is adsorbed, occurs via the development of the Rayleigh-Taylor (RT) instability on the membrane surface. An advanced model allows us to look insight some into some phenomena that were observed by experiments but remained not understood [2]. The authors [2] applied tritium autoradiography to wheat seedlings cultivated with tritium-labeled HS to consider the uptake of humic particles by plant roots. They found a significant increase in the content of some polar (monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfoquinovosyl diacylglycerol (SQDG) and phosphatidylcholine (PC)) and neutral (free fatty acids, FFA) lipids which were detected in the wheat seedlings treated with humic particles. Authors [2] pointed that lipids MGDG, DGDG, SQDG are crucial for functional and structural integrity of the photosystem complex. Therefore, a stimulating action of adsorbed humic particles evoked phenomena like photosynthesis in root cells that can be interpreted using an advanced model: humic particles being nano-size particles become adsorbed on the plant roots in soils, and influence their micro environment, where they are located, with the specific electromagnetic exposure. Another finding of authors consisted in the

  13. Advances in understanding societal vulnerability to tsunamis in the United States

    NASA Astrophysics Data System (ADS)

    Wood, N. J.

    2009-12-01

    Loss of life and property damage from future tsunamis can be reduced if officials develop risk-reduction strategies and education programs that address how at-risk populations and communities are specifically vulnerable to tsunamis. Prior to the 2004 Indian Ocean tsunami, information concerning societal vulnerability to tsunamis in the U.S. was largely limited to state-level summaries of the number of residents within one kilometer of the coast. Since 2004, the U.S. Geological Survey has furthered the Nation’s understanding of societal vulnerability to tsunamis with several studies that describe the exposure, sensitivity, and adaptive capacity of at-risk populations in tsunami-hazard zones. Community-level assessments have been completed in Hawaii, Oregon, and Washington to document variations in the number and types of people, businesses, and critical facilities in tsunami-prone areas. A method using midresolution satellite imagery was developed to identify community variations in the amount of developed land in tsunami-prone areas. Factor analysis and geospatial analysis were integrated to model variations in demographic sensitivity to tsunamis. Public workshops have been held to examine community sensitivity, adaptive capacity and post-tsunami recovery. Results demonstrate that social vulnerability to tsunamis varies throughout a community or region and that certain areas are likely to suffer disproportionately due to differences in pre-tsunami socioeconomic conditions and other demographic attributes. This presentation will summarize advances in understanding societal vulnerability in the U.S. to tsunamis since the 2004 Indian Ocean tsunami, as well as discuss opportunities and needs for further work.

  14. Recent advances in understanding secondary organic aerosols: implications for global climate forcing

    NASA Astrophysics Data System (ADS)

    Shrivastava, Manish

    2017-04-01

    Anthropogenic emissions and land-use changes have modified atmospheric aerosol concentrations and size distributions over time. Understanding pre-industrial conditions and changes in organic aerosol due to anthropogenic activities is important because these features 1) influence estimates of aerosol radiative forcing and 2) can confound estimates of the historical response of climate to increases in greenhouse gases (e.g. the 'climate sensitivity'). Secondary organic aerosol (SOA), formed in the atmosphere by oxidation of organic gases, often represents a major fraction of global submicron-sized atmospheric organic aerosol. Over the past decade, significant advances in understanding SOA properties and formation mechanisms have occurred through measurements, yet current climate models typically do not comprehensively include all important processes. This presentation is based on a US Department of Energy Atmospheric Systems Research sponsored workshop, which highlighted key SOA processes overlooked in climate models that could greatly affect climate forcing estimates. We will highlight the importance of processes that influence the growth of SOA particles to sizes relevant for clouds and radiative forcing, including: formation of extremely low-volatility organics in the gas-phase; isoprene epoxydiols (IEPOX) multi-phase chemistry; particle-phase oligomerization; and physical properties such as viscosity. We also highlight some of the recently discovered important processes that involve interactions between natural biogenic emissions and anthropogenic emissions such as effects of sulfur and NOx emissions on SOA. We will present examples of integrated model-measurement studies that relate the observed evolution of organic aerosol mass and number with knowledge of particle properties such as volatility and viscosity. We will also highlight the importance of continuing efforts to rank the most influential SOA processes that affect climate forcing, but are often missing

  15. Therapeutic Mechanisms of Lithium in Bipolar Disorder: Recent Advances and Current Understanding.

    PubMed

    Malhi, Gin S; Outhred, Tim

    2016-10-01

    Lithium is the most effective and well established treatment for bipolar disorder, and it has a broad array of effects within cellular pathways. However, the specific processes through which therapeutic effects occur and are maintained in bipolar disorder remain unclear. This paper provides a timely update to an authoritative review of pertinent findings that was published in CNS Drugs in 2013. A literature search was conducted using the Scopus database, and was limited by year (from 2012). There has been a resurgence of interest in lithium therapy mechanisms, perhaps driven by technical advancements in recent years that permit the examination of cellular mechanisms underpinning the effects of lithium-along with the reuptake of lithium in clinical practice. Recent research has further cemented glycogen synthase kinase 3β (GSK3β) inhibition as a key mechanism, and the inter-associations between GSK3β-mediated neuroprotective, anti-oxidative and neurotransmission mechanisms have been further elucidated. In addition to highly illustrative cellular research, studies examining higher-order biological systems, such as circadian rhythms, as well as employing innovative animal and human models, have increased our understanding of how lithium-induced changes at the cellular level possibly translate to changes at behavioural and clinical levels. Neural circuitry research is yet to identify clear mechanisms of change in bipolar disorder in response to treatment with lithium, but important structural findings have demonstrated links to the modulation of cellular mechanisms, and peripheral marker and pharmacogenetic studies are showing promising findings that will likely inform the exploration for predictors of lithium treatment response. With a deeper understanding of lithium's therapeutic mechanisms-from the cellular to clinical levels of investigation-comes the opportunity to develop predictive models of lithium treatment response and identify novel drug targets, and

  16. Seasonal Control of Mammalian Energy Balance: Recent Advances in the Understanding of Daily Torpor and Hibernation.

    PubMed

    Jastroch, M; Giroud, S; Barrett, P; Geiser, F; Heldmaier, G; Herwig, A

    2016-11-01

    Endothermic mammals and birds require intensive energy turnover to sustain high body temperatures and metabolic rates. To cope with the energetic bottlenecks associated with the change of seasons, and to minimise energy expenditure, complex mechanisms and strategies are used, such as daily torpor and hibernation. During torpor, metabolic depression and low body temperatures save energy. However, these bouts of torpor, lasting for hours to weeks, are interrupted by active 'euthermic' phases with high body temperatures. These dynamic transitions require precise communication between the brain and peripheral tissues to defend rheostasis in energetics, body mass and body temperature. The hypothalamus appears to be the major control centre in the brain, coordinating energy metabolism and body temperature. The sympathetic nervous system controls body temperature by adjustments of shivering and nonshivering thermogenesis, with the latter being primarily executed by brown adipose tissue. Over the last decade, comparative physiologists have put forward integrative studies on the ecophysiology, biochemistry and molecular regulation of energy balance in response to seasonal challenges, food availability and ambient temperature. Mammals coping with such environments comprise excellent model organisms for studying the dynamic regulation of energy metabolism. Beyond the understanding of how animals survive in nature, these studies also uncover general mechanisms of mammalian energy homeostasis. This research will benefit efforts of translational medicine aiming to combat emerging human metabolic disorders. The present review focuses on recent advances in the understanding of energy balance and its neuronal and endocrine control during the most extreme metabolic fluctuations in nature: daily torpor and hibernation. © 2016 British Society for Neuroendocrinology.

  17. Advancements in the mechanistic understanding of the copper-catalyzed azide-alkyne cycloaddition.

    PubMed

    Berg, Regina; Straub, Bernd F

    2013-12-02

    The copper-catalyzed azide-alkyne cycloaddition (CuAAC) is one of the most broadly applicable and easy-to-handle reactions in the arsenal of organic chemistry. However, the mechanistic understanding of this reaction has lagged behind the plethora of its applications for a long time. As reagent mixtures of copper salts and additives are commonly used in CuAAC reactions, the structure of the catalytically active species itself has remained subject to speculation, which can be attributed to the multifaceted aggregation chemistry of copper(I) alkyne and acetylide complexes. Following an introductory section on common catalyst systems in CuAAC reactions, this review will highlight experimental and computational studies from early proposals to very recent and more sophisticated investigations, which deliver more detailed insights into the CuAAC's catalytic cycle and the species involved. As diverging mechanistic views are presented in articles, books and online resources, we intend to present the research efforts in this field during the past decade and finally give an up-to-date picture of the currently accepted dinuclear mechanism of CuAAC. Additionally, we hope to inspire research efforts on the development of molecularly defined copper(I) catalysts with defined structural characteristics, whose main advantage in contrast to the regularly used precatalyst reagent mixtures is twofold: on the one hand, the characteristics of molecularly defined, well soluble catalysts can be tuned according to the particular requirements of the experiment; on the other hand, the understanding of the CuAAC reaction mechanism can be further advanced by kinetic studies and the isolation and characterization of key intermediates.

  18. Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

    PubMed Central

    2013-01-01

    Summary The copper-catalyzed azide–alkyne cycloaddition (CuAAC) is one of the most broadly applicable and easy-to-handle reactions in the arsenal of organic chemistry. However, the mechanistic understanding of this reaction has lagged behind the plethora of its applications for a long time. As reagent mixtures of copper salts and additives are commonly used in CuAAC reactions, the structure of the catalytically active species itself has remained subject to speculation, which can be attributed to the multifaceted aggregation chemistry of copper(I) alkyne and acetylide complexes. Following an introductory section on common catalyst systems in CuAAC reactions, this review will highlight experimental and computational studies from early proposals to very recent and more sophisticated investigations, which deliver more detailed insights into the CuAAC’s catalytic cycle and the species involved. As diverging mechanistic views are presented in articles, books and online resources, we intend to present the research efforts in this field during the past decade and finally give an up-to-date picture of the currently accepted dinuclear mechanism of CuAAC. Additionally, we hope to inspire research efforts on the development of molecularly defined copper(I) catalysts with defined structural characteristics, whose main advantage in contrast to the regularly used precatalyst reagent mixtures is twofold: on the one hand, the characteristics of molecularly defined, well soluble catalysts can be tuned according to the particular requirements of the experiment; on the other hand, the understanding of the CuAAC reaction mechanism can be further advanced by kinetic studies and the isolation and characterization of key intermediates. PMID:24367437

  19. Advances in understanding mineral dust and boundary layer processes over the Sahara from Fennec aircraft observations

    NASA Astrophysics Data System (ADS)

    Ryder, C. L.; McQuaid, J. B.; Flamant, C.; Washington, R.; Brindley, H. E.; Highwood, E. J.; Marsham, J. H.; Parker, D. J.; Todd, M. C.; Banks, J. R.; Brooke, J. K.; Engelstaedter, S.; Estellés, V.; Formenti, P.; Garcia-Carreras, L.; Kocha, C.; Marenco, F.; Rosenberg, P.; Sodemann, H.; Allen, C. J. T.; Bourdon, A.; Bart, M.; Cavazos-Guerra, C.; Chevaillier, S.; Crosier, J.; Darbyshire, E.; Dean, A. R.; Dorsey, J. R.; Kent, J.; O'Sullivan, D.; Schepanski, K.; Szpek, K.; Woolley, A.

    2015-01-01

    The Fennec climate program aims to improve understanding of the Saharan climate system through a synergy of observations and modelling. We present a description of the Fennec airborne observations during 2011 and 2012 over the remote Sahara (Mauritania and Mali) and the advances in the understanding of mineral dust and boundary layer processes they have provided. Aircraft instrumentation aboard the UK FAAM BAe146 and French SAFIRE Falcon 20 is described, with specific focus on instrumentation specially developed and relevant to Saharan meteorology and dust. Flight locations, aims and associated meteorology are described. Examples and applications of aircraft measurements from the Fennec flights are presented, highlighting new scientific results delivered using a synergy of different instruments and aircraft. These include: (1) the first airborne measurement of dust particles sized up to 300 microns and associated dust fluxes in the Saharan atmospheric boundary layer (SABL), (2) dust uplift from the breakdown of the nocturnal low-level jet before becoming visible in SEVIRI satellite imagery, (3) vertical profiles of the unique vertical structure of turbulent fluxes in the SABL, (4) in-situ observations of processes in SABL clouds showing dust acting as CCN and IN at -15 °C, (5) dual-aircraft observations of the SABL dynamics, thermodynamics and composition in the Saharan heat low region (SHL), (6) airborne observations of a dust storm associated with a cold-pool (haboob) issued from deep convection over the Atlas, (7) the first airborne chemical composition measurements of dust in the SHL region with differing composition, sources (determined using Lagrangian backward trajectory calculations) and absorption properties between 2011 and 2012, (8) coincident ozone and dust surface area measurements suggest coarser particles provide a route for ozone depletion, (9) discrepancies between airborne coarse mode size distributions and AERONET sunphotometer retrievals under

  20. Research Registries: A Tool to Advance Understanding of Rare Neuro-Ophthalmic Diseases

    PubMed Central

    Blankshain, Kimberly D; Moss, Heather E

    2016-01-01

    Background Medical research registries (MRR) are organized systems used to collect, store and analyze patient information. They are important tools for medical research with particular application to the study of rare diseases, including those seen in neuro-ophthalmic practice. Evidence Acquisition Evidence for this review was gathered from the writers’ experiences creating a comprehensive neuro-ophthalmology registry and review of the literature. Results MRR are typically observational and prospective databases of de-identified patient information. The structure is flexible and can accommodate a focus on specific diseases or treatments, surveillance of patient populations, physician quality improvement, or recruitment for future studies. They are particularly useful for the study of rare diseases. They can be integrated into the hierarchy of medical research at many levels provided their construction is well organized and they have several key characteristics including an easily manipulated database, comprehensive information on carefully selected patients and comply with human subjects regulations. MRR pertinent to neuro-ophthalmology include the UIC neuro-ophthalmology registry, Susac Syndrome Registry, Intracranial Hypertension Registry as well as larger scale patient outcome registries being developed by professional societies. Conclusion Medical research registries have a variety of forms and applications. With careful planning and clear goals, they are flexible and powerful research tools that can support multiple different study designs, and through this have the potential to advance understanding and care of neuro-ophthalmic diseases. PMID:27389624

  1. Two decades of numerical modelling to understand long term fluvial archives: Advances and future perspectives

    NASA Astrophysics Data System (ADS)

    Veldkamp, A.; Baartman, J. E. M.; Coulthard, T. J.; Maddy, D.; Schoorl, J. M.; Storms, J. E. A.; Temme, A. J. A. M.; van Balen, R.; van De Wiel, M. J.; van Gorp, W.; Viveen, W.; Westaway, R.; Whittaker, A. C.

    2017-06-01

    The development and application of numerical models to investigate fluvial sedimentary archives has increased during the last decades resulting in a sustained growth in the number of scientific publications with keywords, 'fluvial models', 'fluvial process models' and 'fluvial numerical models'. In this context we compile and review the current contributions of numerical modelling to the understanding of fluvial archives. In particular, recent advances, current limitations, previous unexpected results and future perspectives are all discussed. Numerical modelling efforts have demonstrated that fluvial systems can display non-linear behaviour with often unexpected dynamics causing significant delay, amplification, attenuation or blurring of externally controlled signals in their simulated record. Numerical simulations have also demonstrated that fluvial records can be generated by intrinsic dynamics without any change in external controls. Many other model applications demonstrate that fluvial archives, specifically of large fluvial systems, can be convincingly simulated as a function of the interplay of (palaeo) landscape properties and extrinsic climate, base level and crustal controls. All discussed models can, after some calibration, produce believable matches with real world systems suggesting that equifinality - where a given end state can be reached through many different pathways starting from different initial conditions and physical assumptions - plays an important role in fluvial records and their modelling. The overall future challenge lies in the development of new methodologies for a more independent validation of system dynamics and research strategies that allow the separation of intrinsic and extrinsic record signals using combined fieldwork and modelling.

  2. Recent advances in the understanding of Quaternary periglacial features of the English Channel coastlands

    NASA Astrophysics Data System (ADS)

    Murton, Julian B.; Lautridou, Jean-Pierre

    2003-02-01

    Recent advances in the understanding of Quaternary periglaciation of the English Channel coastlands concern laboratory modelling of periglacial processes, dating of periglacial sediments and the distribution of permafrost during marine oxygen isotope stage (MOIS) 2. Modelling studies have successfully simulated (i) ice segregation in chalk in artificial permafrost, (ii) periglacial solifluction of natural slope sediments, and (iii) soft-sediment deformation during thaw of ice-rich soil. The resultant structures and deposits in these experiments have similarities with naturally brecciated chalk, solifluction deposits and involutions, respectively, along the English Channel coastlands, providing insights into their genesis and palaeoenvironmental significance.Dating of periglacial sediments is based on radiocarbon assays of organic material in head deposits, luminescence measurements of loess and coversand, and mammalian biostratigraphy in raised-beach and associated slope deposits. Most age estimates fall within MOIS 2, although some are within MOIS 6 and possibly other cold stages.Maps reconstructing the distribution of permafrost during MOIS 2 vary in detail. The precise distribution of permafrost remains to be established owing to problems of (i) imprecise dating in the context of climatic instability, (ii) uncertain palaeoclimatic significance of particular periglacial structures and (iii) sparse data on the age and distribution of relict periglacial features.The wider significance of periglacial processes to the evolution of the Channel coastlands is speculated to involve rapid valley development by flowing water in areas of moist, frost-susceptible bedrock that has been brecciated by ice segregation.

  3. Novel Advances in Understanding of Molecular Pathogenesis of Hepatoblastoma: A Wnt/β-Catenin Perspective

    PubMed Central

    Bell, Danielle; Ranganathan, Sarangarajan; Tao, Junyan; Monga, Satdarshan P. S.

    2017-01-01

    Hepatoblastoma is the most common pediatric liver malignancy, typically striking children within the first 3 years of their young lives. While advances in chemotherapy and newer surgical techniques have improved survival in patients with localized disease, unfortunately, for the 25% of patients with metastasis, the overall survival remains poor. These tumors, which are thought to arise from hepatic progenitors or hepatoblasts, hence the name hepatoblastoma, can be categorized by histological subtyping based on their level of cell differentiation. Genomic and histological analysis of human tumor samples has shown exon-3 deletions or missense mutations in gene coding for β-catenin, a downstream effector of the Wnt signaling pathway, in up to 90% of hepatoblastoma cases. The current article will review key aberrations in molecular pathways that are implicated in various subtypes of hepatoblastoma with an emphasis on Wnt signaling. It will also discuss cooperation among components of pathways such as β-catenin and Yes-associated protein in cancer development. Understanding the complex network of molecular signaling in oncogenesis will undoubtedly aid in the discovery of new therapeutics to help combat hepatoblastoma. PMID:27938502

  4. Advances in understanding the complex mechanisms of DNA interstrand cross-link repair.

    PubMed

    Clauson, Cheryl; Schärer, Orlando D; Niedernhofer, Laura

    2013-10-01

    DNA interstrand cross-links (ICLs) are lesions caused by a variety of endogenous metabolites, environmental exposures, and cancer chemotherapeutic agents that have two reactive groups. The common feature of these diverse lesions is that two nucleotides on opposite strands are covalently joined. ICLs prevent the separation of two DNA strands and therefore essential cellular processes including DNA replication and transcription. ICLs are mainly detected in S phase when a replication fork stalls at an ICL. Damage signaling and repair of ICLs are promoted by the Fanconi anemia pathway and numerous posttranslational modifications of DNA repair and chromatin structural proteins. ICLs are also detected and repaired in nonreplicating cells, although the mechanism is less clear. A unique feature of ICL repair is that both strands of DNA must be incised to completely remove the lesion. This is accomplished in sequential steps to prevent creating multiple double-strand breaks. Unhooking of an ICL from one strand is followed by translesion synthesis to fill the gap and create an intact duplex DNA, harboring a remnant of the ICL. Removal of the lesion from the second strand is likely accomplished by nucleotide excision repair. Inadequate repair of ICLs is particularly detrimental to rapidly dividing cells, explaining the bone marrow failure characteristic of Fanconi anemia and why cross-linking agents are efficacious in cancer therapy. Herein, recent advances in our understanding of ICLs and the biological responses they trigger are discussed.

  5. Guard Cell Signal Transduction Network: Advances in Understanding Abscisic Acid, CO2, and Ca2+ Signaling

    PubMed Central

    Kim, Tae-Houn; Böhmer, Maik; Hu, Honghong; Nishimura, Noriyuki; Schroeder, Julian I.

    2011-01-01

    Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO2 influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO2 activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO2 and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO2-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms. PMID:20192751

  6. Bovine viral diarrhea virus infections: manifestations of infection and recent advances in understanding pathogenesis and control.

    PubMed

    Brodersen, B W

    2014-03-01

    Bovine viral diarrhea virus (BVDV) continues to be of economic significance to the livestock industry in terms of acute disease and fetal loss. Many of the lesions relating to BVDV infection have been well described previously. The virus is perpetuated in herds through the presence of calves that are persistently infected. Relationships between various species and biotypes of BVDV and host defenses are increasingly understood. Understanding of the host defense mechanisms of innate immunity and adaptive immunity continues to improve, and the effects of the virus on these immune mechanisms are being used to explain how persistent infection develops. The noncytopathic biotype of BVDV plays the major role in its effects on the host defenses by inhibiting various aspects of the innate immune system and creation of immunotolerance in the fetus during early gestation. Recent advances have allowed for development of affordable test strategies to identify and remove persistently infected animals. With these improved tests and removal strategies, the livestock industry can begin more widespread effective control programs.

  7. Advancing our understanding of religion and spirituality in the context of behavioral medicine.

    PubMed

    Park, Crystal L; Masters, Kevin S; Salsman, John M; Wachholtz, Amy; Clements, Andrea D; Salmoirago-Blotcher, Elena; Trevino, Kelly; Wischenka, Danielle M

    2017-02-01

    Recognizing and understanding the potentially powerful roles that religiousness and spirituality (RS) may serve in the prevention and amelioration of disease, as well as symptom management and health related quality of life, significantly enhances research and clinical efforts across many areas of behavioral medicine. This article examines the knowledge established to date and suggests advances that remain to be made. We begin with a brief summary of the current knowledge regarding RS as related to three exemplary health conditions: (a) cardiovascular disease; (b) cancer; and, (c) substance abuse. We then focus on particular concerns for future investigations, emphasizing conceptual issues, possible mediators and moderators of relationships or effects, and methodology. Our discussion is framed by a conceptual model that may serve to guide and organize future investigations. This model highlights a number of important issues regarding the study of links between RS and health: (a) RS comprise many diverse constructs, (b) the mechanisms through which RS may influence health outcomes are quite diverse, and (c) a range of different types of health and health relevant outcomes may be influenced by RS. The multidimensional nature of RS and the complexity of related associations with different types of health relevant outcomes present formidable challenges to empirical study in behavioral medicine. These issues are referred to throughout our review and we suggest several solutions to the presented challenges in our summary. We end with a presentation of barriers to be overcome, along with strategies for doing so, and concluding thoughts.

  8. Advances in the understanding of myeloma bone disease and tumour growth

    PubMed Central

    Yaccoby, Shmuel

    2010-01-01

    Summary Advances in multiple myeloma support the notion that the associated bone disease, characterized by increased osteoclastogenesis and suppressed osteoblastogenesis, is both a consequence and necessity of tumour progression. Osteoblastogenesis is suppressed by secreted inhibitors and dysregulation of cell-surface “coupling” factors on osteogenic cells. Osteoclastogenesis is increased as a consequence of osteoblast deactivation and of production of osteoclast-activating factors. Osteoclasts express soluble and cell-surface factors that stimulate myeloma growth, while osteoblasts produce bone-building factors that restrain growth of myeloma cells that are dependent on the microenvironment; detailed molecular mechanisms are discussed. Experimental and clinical findings indicate that pharmacological and experimental osteoblast-activating agents that effectively promote bone formation also reduce growth of myeloma cells within bone, seemingly by simultaneously stimulating osteoblastogenesis and restraining osteoclastogenesis. Unravelling mechanisms of myeloma bone disease expands horizons for developing novel interventions and also facilitates better understanding of the association between induction of osteolysis and disease progression. PMID:20230410

  9. Advancing understanding of microbial bioenergy conversion processes by activity-based protein profiling

    DOE PAGES

    Liu, Yun; Fredrickson, James K.; Sadler, Natalie C.; ...

    2015-09-25

    Here, the development of renewable biofuels is a global priority, but success will require novel technologies that greatly improve our understanding of microbial systems biology. An approach with great promise in enabling functional characterization of microbes is activity-based protein profiling (ABPP), which employs chemical probes to directly measure enzyme function in discrete enzyme classes in vivo and/or in vitro, thereby facilitating the rapid discovery of new biocatalysts and enabling much improved biofuel production platforms. We review general design strategies in ABPP, and highlight recent advances that are or could be pivotal to biofuels processes including applications of ABPP to cellulosicmore » bioethanol, biodiesel, and phototrophic production of hydrocarbons. We also examine the key challenges and opportunities of ABPP in renewable biofuels research. The integration of ABPP with molecular and systems biology approaches will shed new insight on the catalytic and regulatory mechanisms of functional enzymes and their synergistic effects in the field of biofuels production.« less

  10. Recent advances in understanding the role of lamins in health and disease

    PubMed Central

    Reddy, Sita; Comai, Lucio

    2016-01-01

    Lamins are major components of the nuclear lamina, a network of proteins that supports the nuclear envelope in metazoan cells. Over the past decade, biochemical studies have provided support for the view that lamins are not passive bystanders providing mechanical stability to the nucleus but play an active role in the organization of the genome and the function of fundamental nuclear processes. It has also become apparent that lamins are critical for human health, as a large number of mutations identified in the gene that encodes for A-type lamins are associated with tissue-specific and systemic genetic diseases, including the accelerated aging disorder known as Hutchinson-Gilford progeria syndrome. Recent years have witnessed great advances in our understanding of the role of lamins in the nucleus and the functional consequences of disease-associated A-type lamin mutations. Many of these findings have been presented in comprehensive reviews. In this mini-review, we discuss recent breakthroughs in the role of lamins in health and disease and what lies ahead in lamin research. PMID:27803806

  11. Research Registries: A Tool to Advance Understanding of Rare Neuro-Ophthalmic Diseases.

    PubMed

    Blankshain, Kimberly D; Moss, Heather E

    2016-09-01

    Medical research registries (MRR) are organized systems used to collect, store, and analyze patient information. They are important tools for medical research with particular application to the study of rare diseases, including those seen in neuro-ophthalmic practice. Evidence for this review was gathered from the writers' experiences creating a comprehensive neuro-ophthalmology registry and review of the literature. MRR are typically observational and prospective databases of de-identified patient information. The structure is flexible and can accommodate a focus on specific diseases or treatments, surveillance of patient populations, physician quality improvement, or recruitment for future studies. They are particularly useful for the study of rare diseases. They can be integrated into the hierarchy of medical research at many levels provided their construction is well organized and they have several key characteristics including an easily manipulated database, comprehensive information on carefully selected patients, and comply with human subjects regulations. MRR pertinent to neuro-ophthalmology include the University of Illinois at Chicago neuro-ophthalmology registry, Susac Syndrome Registry, Intracranial Hypertension Registry, and larger-scale patient outcome registries being developed by professional societies. MRR have a variety of forms and applications. With careful planning and clear goals, they are flexible and powerful research tools that can support multiple different study designs, and this can provide the potential to advance understanding and care of neuro-ophthalmic diseases.

  12. Recent advances in the understanding of the Aspergillus fumigatus cell wall.

    PubMed

    Lee, Mark J; Sheppard, Donald C

    2016-03-01

    Over the past several decades, research on the synthesis and organization of the cell wall polysaccharides of Aspergillus fumigatus has expanded our knowledge of this important fungal structure. Besides protecting the fungus from environmental stresses and maintaining structural integrity of the organism, the cell wall is also the primary site for interaction with host tissues during infection. Cell wall polysaccharides are important ligands for the recognition of fungi by the innate immune system and they can mediate potent immunomodulatory effects. The synthesis of cell wall polysaccharides is a complicated process that requires coordinated regulation of many biosynthetic and metabolic pathways. Continuous synthesis and remodeling of the polysaccharides of the cell wall is essential for the survival of the fungus during development, reproduction, colonization and invasion. As these polysaccharides are absent from the human host, these biosynthetic pathways are attractive targets for antifungal development. In this review, we present recent advances in our understanding of Aspergillus fumigatus cell wall polysaccharides, including the emerging role of cell wall polysaccharides in the host-pathogen interaction.

  13. Advancing Fourth-Grade Students' Understanding of Arithmetic Properties with Instruction That Promotes Mathematical Argumentation

    ERIC Educational Resources Information Center

    Rumsey, Chepina Witkowski

    2012-01-01

    The goals for this study were to investigate how fourth-grade students developed an understanding of the arithmetic properties when instruction promoted mathematical argumentation and to identify the characteristics of students' arguments. Using the emergent perspective as an overarching theoretical perspective helped distinguish between two…

  14. Using a Vulnerability Theoretical Model to Assess the Malignant Hyperthermia Susceptible Population: Implications for Advanced Practice Emergency Nurses.

    PubMed

    Denholm, Bonnie G

    2015-01-01

    Malignant hyperthermia (MH) is a high-risk, low-occurrence medical emergency with symptoms that include a severe increased rate of metabolic activity and rigid skeletal muscles. Clinicians should be knowledgeable and prepared for an MH event because it can occur in areas outside the operating room and without anesthetic triggers. Patients who have this rare genetic condition may come to the emergency department (ED) presenting with symptoms of heat stroke. However, the incidence of suspected MH in the ED or other critical care areas is not easily quantifiable because clinicians may not report cases to a centralized registry. The purpose of this article is to describe the MH-susceptible vulnerable population, to apply a vulnerability theoretical model to assess patients and families, to identify strategies for health promotion to reduce vulnerability, and to discuss how advanced practice nurses who specialize in emergency care can help decrease the vulnerability of MH-susceptible patients and families. By using a vulnerability model to assess the MH-susceptible population, nurses can effectively sort out strategies to prevent poor patient outcomes related to MH and promote health for this high-risk population. Measuring accurate core temperatures, applying effective cooling methods, and administering dantrolene are key concepts in caring for a patient who is experiencing an MH event. Advanced practice emergency nurses can participate in reducing vulnerability for this population by applying the Emergency Nurses Association Clinical Nurse Specialist competencies to MH-related vulnerabilities. Enhancing preparedness, evaluating and coordinating education programs, advocating for report submissions to the North American Malignant Hyperthermia Registry, and assessing opportunities for community collaboration are among the strategies discussed for reducing vulnerability for the MH-susceptible population.

  15. Managing in the trenches of consumer care: the challenges of understanding and initiating the advance care planning process.

    PubMed

    Baughman, Kristin R; Aultman, Julie; Hazelett, Susan; Palmisano, Barbara; O'Neill, Anne; Ludwick, Ruth; Sanders, Margaret

    2012-01-01

    To better understand how community-based long-term care providers define advance care planning and their role in the process, we conducted 8 focus groups with 62 care managers (social workers and registered nurses) providing care for Ohio's Medicaid waiver program. Care managers shared that most consumers had little understanding of advance care planning. The care managers defined it broadly, including legal documentation, social aspects, medical considerations, ongoing communication, and consumer education. Care managers saw their roles as information providers, healthcare team members, and educators/coaches. Better education, resources, and coordination are needed to ensure that consumer preferences are realized.

  16. Advancing the application of systems thinking in health: understanding the dynamics of neonatal mortality in Uganda

    PubMed Central

    2014-01-01

    internal audits at the health facilities as well as addressing the gaps in resources (human, logistics, and drugs). Conclusions Synthesis of theoretical concepts through CLDs facilitated our understanding and interpretation of the interactions and feedback loops that contributed to the stagnant neonatal mortality rates in Uganda, which is the first step towards discussing and exploring the potential strategies and their likely impact. PMID:25104047

  17. Advancing the application of systems thinking in health: understanding the dynamics of neonatal mortality in Uganda.

    PubMed

    Rwashana, Agnes Semwanga; Nakubulwa, Sarah; Nakakeeto-Kijjambu, Margaret; Adam, Taghreed

    2014-08-08

    facilities as well as addressing the gaps in resources (human, logistics, and drugs). Synthesis of theoretical concepts through CLDs facilitated our understanding and interpretation of the interactions and feedback loops that contributed to the stagnant neonatal mortality rates in Uganda, which is the first step towards discussing and exploring the potential strategies and their likely impact.

  18. Issues and Advances in Understanding Landslide-Generated Tsunamis: Toward a Unified Model

    NASA Astrophysics Data System (ADS)

    Geist, E. L.; Locat, J.; Lee, H. J.; Lynett, P. J.; Parsons, T.; Kayen, R. E.; Hart, P. E.

    2008-12-01

    The physics of tsunamis generated from submarine landslides is highly complex, involving a cross- disciplinary exchange in geophysics. In the 10 years following the devastating Papua New Guinea tsunami, there have been significant advances in understanding landslide-generated tsunamis. However, persistent issues still remain related to submarine landslide dynamics that may be addressed with collection of new marine geologic and geophysical observations. We review critical elements of landslide tsunamis in the hope of developing a unified model that encompasses all stages of the process from triggering to tsunami runup. Because the majority of non-volcanogenic landslides that generate tsunamis are triggered seismically, advances in understanding inertial displacements and changes in strength and rheologic properties in response to strong-ground motion need to be included in a unified model. For example, interaction between compliant marine sediments and multi-direction ground motion results in greater permanent plastic displacements than predicted by traditional rigid-block analysis. When considering the coupling of the overlying water layer in the generation of tsunamis, the post-failure dynamics of landslides is important since the overall rate of seafloor deformation for landslides is less than or comparable to the phase speed of tsunami waves. As such, the rheologic and mechanical behavior of the slide material needs to be well understood. For clayey and silty debris flows, a non-linear (Herschel-Bulkley) and bilinear rheology have recently been developed to explain observed runout distances and deposit thicknesses. An additional complexity to this rheology is the inclusion of hydrate-laden sediment that commonly occurs along continental slopes. Although it has been proposed in the past that gas hydrate dissociation may provide potential failure planes for slide movement, it is unclear how zones of rigid hydrate-bearing sediment surrounded by a more viscoplastic

  19. Advancing our understanding of the onshore propagation of tsunami bores over rough surfaces through numerical modeling

    NASA Astrophysics Data System (ADS)

    Marras, S.; Suckale, J.; Eguzkitza, B.; Houzeaux, G.; Vázquez, M.; Lesage, A. C.

    2016-12-01

    The propagation of tsunamis in the open ocean has been studied in detail with many excellent numerical approaches available to researchers. Our understanding of the processes that govern the onshore propagation of tsunamis is less advanced. Yet, the reach of tsunamis on land is an important predictor of the damage associated with a given event, highlighting the need to investigate the factors that govern tsunami propagation onshore. In this study, we specifically focus on understanding the effect of bottom roughness at a variety of scales. The term roughness is to be understood broadly, as it represents scales ranging from small features like rocks, to vegetation, up to the size of larger structures and topography. In this poster, we link applied mathematics, computational fluid dynamics, and tsunami physics to analyze the small scales features of coastal hydrodynamics and the effect of roughness on the motion of tsunamis as they run up a sloping beach and propagate inland. We solve the three-dimensional Navier-Stokes equations of incompressible flows with free surface, which is tracked by a level set function in combination with an accurate re-distancing scheme. We discretize the equations via linear finite elements for space approximation and fully implicit time integration. Stabilization is achieved via the variational multiscale method whereas the subgrid scales for our large eddy simulations are modeled using a dynamically adaptive Smagorinsky eddy viscosity. As the geometrical characteristics of roughness in this study vary greatly across different scales, we implement a scale-dependent representation of the roughness elements. We model the smallest sub-grid scale roughness features by the use of a properly defined law of the wall. Furthermore, we utilize a Manning formula to compute the shear stress at the boundary. As the geometrical scales become larger, we resolve the geometry explicitly and compute the effective volume drag introduced by large scale

  20. Advances in understanding mineral dust and boundary layer processes over the Sahara from Fennec aircraft observations

    NASA Astrophysics Data System (ADS)

    Ryder, C. L.; McQuaid, J. B.; Flamant, C.; Rosenberg, P. D.; Washington, R.; Brindley, H. E.; Highwood, E. J.; Marsham, J. H.; Parker, D. J.; Todd, M. C.; Banks, J. R.; Brooke, J. K.; Engelstaedter, S.; Estelles, V.; Formenti, P.; Garcia-Carreras, L.; Kocha, C.; Marenco, F.; Sodemann, H.; Allen, C. J. T.; Bourdon, A.; Bart, M.; Cavazos-Guerra, C.; Chevaillier, S.; Crosier, J.; Darbyshire, E.; Dean, A. R.; Dorsey, J. R.; Kent, J.; O'Sullivan, D.; Schepanski, K.; Szpek, K.; Trembath, J.; Woolley, A.

    2015-07-01

    The Fennec climate programme aims to improve understanding of the Saharan climate system through a synergy of observations and modelling. We present a description of the Fennec airborne observations during 2011 and 2012 over the remote Sahara (Mauritania and Mali) and the advances in the understanding of mineral dust and boundary layer processes they have provided. Aircraft instrumentation aboard the UK FAAM BAe146 and French SAFIRE (Service des Avions Français Instrumentés pour la Recherche en Environnement) Falcon 20 is described, with specific focus on instrumentation specially developed for and relevant to Saharan meteorology and dust. Flight locations, aims and associated meteorology are described. Examples and applications of aircraft measurements from the Fennec flights are presented, highlighting new scientific results delivered using a synergy of different instruments and aircraft. These include (1) the first airborne measurement of dust particles sizes of up to 300 microns and associated dust fluxes in the Saharan atmospheric boundary layer (SABL), (2) dust uplift from the breakdown of the nocturnal low-level jet before becoming visible in SEVIRI (Spinning Enhanced Visible Infra-Red Imager) satellite imagery, (3) vertical profiles of the unique vertical structure of turbulent fluxes in the SABL, (4) in situ observations of processes in SABL clouds showing dust acting as cloud condensation nuclei (CCN) and ice nuclei (IN) at -15 °C, (5) dual-aircraft observations of the SABL dynamics, thermodynamics and composition in the Saharan heat low region (SHL), (6) airborne observations of a dust storm associated with a cold pool (haboob) issued from deep convection over the Atlas Mountains, (7) the first airborne chemical composition measurements of dust in the SHL region with differing composition, sources (determined using Lagrangian backward trajectory calculations) and absorption properties between 2011 and 2012, (8) coincident ozone and dust surface area

  1. Antifungal Therapy: New Advances in the Understanding and Treatment of Mycosis.

    PubMed

    Scorzoni, Liliana; de Paula E Silva, Ana C A; Marcos, Caroline M; Assato, Patrícia A; de Melo, Wanessa C M A; de Oliveira, Haroldo C; Costa-Orlandi, Caroline B; Mendes-Giannini, Maria J S; Fusco-Almeida, Ana M

    2017-01-01

    The high rates of morbidity and mortality caused by fungal infections are associated with the current limited antifungal arsenal and the high toxicity of the compounds. Additionally, identifying novel drug targets is challenging because there are many similarities between fungal and human cells. The most common antifungal targets include fungal RNA synthesis and cell wall and membrane components, though new antifungal targets are being investigated. Nonetheless, fungi have developed resistance mechanisms, such as overexpression of efflux pump proteins and biofilm formation, emphasizing the importance of understanding these mechanisms. To address these problems, different approaches to preventing and treating fungal diseases are described in this review, with a focus on the resistance mechanisms of fungi, with the goal of developing efficient strategies to overcoming and preventing resistance as well as new advances in antifungal therapy. Due to the limited antifungal arsenal, researchers have sought to improve treatment via different approaches, and the synergistic effect obtained by the combination of antifungals contributes to reducing toxicity and could be an alternative for treatment. Another important issue is the development of new formulations for antifungal agents, and interest in nanoparticles as new types of carriers of antifungal drugs has increased. In addition, modifications to the chemical structures of traditional antifungals have improved their activity and pharmacokinetic parameters. Moreover, a different approach to preventing and treating fungal diseases is immunotherapy, which involves different mechanisms, such as vaccines, activation of the immune response and inducing the production of host antimicrobial molecules. Finally, the use of a mini-host has been encouraging for in vivo testing because these animal models demonstrate a good correlation with the mammalian model; they also increase the speediness of as well as facilitate the

  2. Antifungal Therapy: New Advances in the Understanding and Treatment of Mycosis

    PubMed Central

    Scorzoni, Liliana; de Paula e Silva, Ana C. A.; Marcos, Caroline M.; Assato, Patrícia A.; de Melo, Wanessa C. M. A.; de Oliveira, Haroldo C.; Costa-Orlandi, Caroline B.; Mendes-Giannini, Maria J. S.; Fusco-Almeida, Ana M.

    2017-01-01

    The high rates of morbidity and mortality caused by fungal infections are associated with the current limited antifungal arsenal and the high toxicity of the compounds. Additionally, identifying novel drug targets is challenging because there are many similarities between fungal and human cells. The most common antifungal targets include fungal RNA synthesis and cell wall and membrane components, though new antifungal targets are being investigated. Nonetheless, fungi have developed resistance mechanisms, such as overexpression of efflux pump proteins and biofilm formation, emphasizing the importance of understanding these mechanisms. To address these problems, different approaches to preventing and treating fungal diseases are described in this review, with a focus on the resistance mechanisms of fungi, with the goal of developing efficient strategies to overcoming and preventing resistance as well as new advances in antifungal therapy. Due to the limited antifungal arsenal, researchers have sought to improve treatment via different approaches, and the synergistic effect obtained by the combination of antifungals contributes to reducing toxicity and could be an alternative for treatment. Another important issue is the development of new formulations for antifungal agents, and interest in nanoparticles as new types of carriers of antifungal drugs has increased. In addition, modifications to the chemical structures of traditional antifungals have improved their activity and pharmacokinetic parameters. Moreover, a different approach to preventing and treating fungal diseases is immunotherapy, which involves different mechanisms, such as vaccines, activation of the immune response and inducing the production of host antimicrobial molecules. Finally, the use of a mini-host has been encouraging for in vivo testing because these animal models demonstrate a good correlation with the mammalian model; they also increase the speediness of as well as facilitate the

  3. Recent advances in the understanding and management of atrial fibrillation: a focus on stroke prevention

    PubMed Central

    Shahid, Farhan; Shantsila, Eduard; Lip, Gregory Y. H.

    2016-01-01

    Atrial fibrillation (AF) is associated with an increased risk of stroke compared with the general population. It is anticipated that by 2030 an estimated 14–17 million patients will be diagnosed with this most prevalent arrhythmia within the European Union. AF-related stroke confers a higher mortality and morbidity risk, and thus early detection and assessment for the initiation of effective stroke prevention with oral anticoagulation (OAC) is crucial. Recent guidelines point to the use of non-vitamin K antagonist OACs (NOACs) where appropriate in stroke prevention of patients with non-valvular AF. At present, there are four NOACS available, with no direct head-to-head comparisons to suggest the superiority of one drug over another. Simple and practical risk assessment tools have evolved over the years to facilitate stroke and bleeding risk assessment in busy clinics and wards to aid decision-making. At present, the CHA 2DS 2VASc (congestive heart failure, hypertension, age 65–74/>75, diabetes mellitus, stroke/transient ischemic attack/thromboembolism, vascular disease, female sex) score is recommended by many international guidelines as a simple and practical method of assessing stroke risk in such patients. Alongside this, use of the HAS BLED (hypertension systolic blood pressure >160 mmHg, abnormal liver/renal function [with creatinine ≥200 μmol/L], stroke, bleeding history or predisposition, labile international normalized ratio [range <60% of the time], elderly [>65], concomitant drugs/alcohol) score aims to identify patients at high risk of bleeding for more regular review and follow-up and draws attention to potentially reversible bleeding risk factors. The aim of this review article is to provide an overview of recent advances in the understanding and management of AF with a focus on stroke prevention. PMID:28105320

  4. Experimental alluvial fans: Advances in understanding of fan dynamics and processes

    NASA Astrophysics Data System (ADS)

    Clarke, Lucy E.

    2015-09-01

    Alluvial fans are depositional systems that develop because of a disparity between the upstream and downstream sediment transport capacity of a system, usually at the base of mountain fronts as rivers emerge from the constrained mountain area onto the plain. They are dynamic landforms that are prone to abrupt changes on a geomorphological (decades to centuries) time scale, while also being long-term deposition features that preserve sedimentary strata and are sensitive indictors of environmental change. The complexity of interactions between catchment characteristics, climate, tectonics, internal system feedbacks, and environmental processes on field alluvial fans means that it is difficult to isolate individual variables in a field setting; therefore, the controlled conditions afforded by experimental models has provided a novel technique to overcome some of these complexities. The use of experimental models of alluvial fans has a long history and these have been implemented over a range of different research areas utilising various experimental designs. Using this technique, important advances have been made in determining the primary factors influencing fan slope, understanding of avulsion dynamics, identifying autogenic processes driving change on fan systems independent of any change in external conditions, and the mechanics of flow and flood risk on alluvial fans, to name a few. However, experiments cannot be carried out in isolation. Thus, combining the findings from experimental alluvial fans with field research and numerical modelling is important and, likewise, using these techniques to inform experimental design. If this can be achieved, there is potential for future experimental developments to explore key alluvial fan issues such as stratigraphic preservation potential and simulating extra terrestrial fan systems.

  5. The influence of practice educators on occupational therapy students' understanding of the practical applications of theoretical knowledge: a phenomenological study into student experiences of practice education.

    PubMed

    Towns, Emma; Ashby, Samantha

    2014-10-01

    Practice education is a compulsory component of all entry-level programmes in the health professions. It is used as a teaching strategy to connect theoretical knowledge, such as occupation-focussed models with practice. The study aimed to explore students' perceptions about the influence of practice educators on their understanding of the use of occupation-focussed models in practice. Using a phenomenological approach, semi-structured interviews gained an understanding of six participants' experiences of their practice education. Interview transcripts were analysed thematically. Three themes emerged from participants' experiences of practice education. 'Explaining the theory-practice nexus' referred to participants' difficulties in distinguishing between different forms of theoretical knowledge, it described educators struggle to fulfil the dual roles of educator and practitioner' when articulating the theoretical knowledge underpinning practice. This often led participants taking an active role in their own learning. 'Experiencing dissonance between university-based studies and the real-world' described the difference between the importance university studies placed on theory in comparison to practice. 'Creating a positive mindset for the use of theoretical knowledge in practice for future practice' illustrated strategies used by some practice educators to articulate the use of theoretical knowledge. The study highlighted practice educators role in shaping students' perceptions of theoretical knowledge use in professional reasoning. The increased recognition of practice educators on the implicit curricula creates an onus on the university sector to provide discussion and information exchanges to increase educators' opportunities to develop, update and increase their skills in describing and using theoretical knowledge to underpin practice. © 2014 Occupational Therapy Australia.

  6. Reciprocal and Scholarly Service Learning: Emergent Theoretical Understandings of the University-Community Interface in South Africa

    ERIC Educational Resources Information Center

    Smith-Tolken, Antoinette; Bitzer, Eli

    2017-01-01

    This study addresses underlying principles to interpret scholarly-based service-related teaching and learning. Such principles include addressing specific concerns of communities, transforming theoretical knowledge into lived experiences for students, making the knowledge generated within communities meaningful and forging constant growth and…

  7. Reciprocal and Scholarly Service Learning: Emergent Theoretical Understandings of the University-Community Interface in South Africa

    ERIC Educational Resources Information Center

    Smith-Tolken, Antoinette; Bitzer, Eli

    2017-01-01

    This study addresses underlying principles to interpret scholarly-based service-related teaching and learning. Such principles include addressing specific concerns of communities, transforming theoretical knowledge into lived experiences for students, making the knowledge generated within communities meaningful and forging constant growth and…

  8. APPLICATION OF ADVANCED IN VITRO TECHNIQUES TO MEASURE, UNDERSTAND AND PREDICT THE KINETICS AND MECHANISMS OF XENOBIOTIC METABOLISM

    EPA Science Inventory

    We have developed a research program in metabolism that involves numerous collaborators across EPA as well as other federal and academic labs. A primary goal is to develop and apply advanced in vitro techniques to measure, understand and predict the kinetics and mechanisms of xen...

  9. APPLICATION OF ADVANCED IN VITRO TECHNIQUES TO MEASURE, UNDERSTAND AND PREDICT THE KINETICS AND MECHANISMS OF XENOBIOTIC METABOLISM

    EPA Science Inventory

    We have developed a research program in metabolism that involves numerous collaborators across EPA as well as other federal and academic labs. A primary goal is to develop and apply advanced in vitro techniques to measure, understand and predict the kinetics and mechanisms of xen...

  10. Advancement Information Resources Management: An Information Understanding Profession in Support of Philanthropy.

    ERIC Educational Resources Information Center

    Mayer, Anne E.

    Professional fundraising has given rise to a new information specialist profession. This career path, which has been known as prospect research or advancement research, should be more accurately characterized as information resources management for advancement. With primary emphasis on value-added information processes that involve analysis and…

  11. Advances in Understanding Air Pollution and Cardiovascular Diseases: The Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air)

    PubMed Central

    Kaufman, Joel D.; Spalt, Elizabeth W.; Curl, Cynthia L.; Hajat, Anjum; Jones, Miranda R.; Kim, Sun-Young; Vedal, Sverre; Szpiro, Adam A.; Gassett, Amanda; Sheppard, Lianne; Daviglus, Martha L.; Adar, Sara D.

    2016-01-01

    The Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air) leveraged the platform of the MESA cohort into a prospective longitudinal study of relationships between air pollution and cardiovascular health. MESA Air researchers developed fine-scale, state-of-the-art air pollution exposure models for the MESA Air communities, creating individual exposure estimates for each participant. These models combine cohort-specific exposure monitoring, existing monitoring systems, and an extensive database of geographic and meteorological information. Together with extensive phenotyping in MESA—and adding participants and health measurements to the cohort—MESA Air investigated environmental exposures on a wide range of outcomes. Advances by the MESA Air team included not only a new approach to exposure modeling but also biostatistical advances in addressing exposure measurement error and temporal confounding. The MESA Air study advanced our understanding of the impact of air pollutants on cardiovascular disease and provided a research platform for advances in environmental epidemiology. PMID:27741981

  12. Understanding of the Dynamics of the Stirling Convertor Advanced by Structural Testing

    NASA Technical Reports Server (NTRS)

    Hughes, William O.

    2003-01-01

    associated harmonics. Therefore, Stirling power systems will not disturb spacecraft science experiments if minimal appropriate mounting efforts are made. The third test program, performed in February and May 2001, resulted in a modal characterization of a Stirling convertor. Since the deflection of the TDC piston rod, under vibration excitation, was of particular interest, the outer pressure shell was removed to allow access to the rod. Through this testing, the Stirling TDC's natural frequencies and modes were identified. This knowledge advanced our understanding of the successful 1999 vibration test and may be utilized to optimize the output power of future Stirling designs. The fourth test program, in April 2001, was conducted to characterize the structural response of a pair of Stirling convertors, as a function of their mounting interface stiffness. The test results provide guidance for the Stirling power package interface design. Properly designed, the interface may lead to increased structural capability and power performance beyond what was demonstrated in the successful 1999 vibration test. Dynamic testing performed to date at Glenn has shown that the Stirling convertors can withstand liftoff random vibration environments and meet "good neighbor" vibratory emission requirements. Furthermore, the future utilization of the information obtained during the tests will allow the corporation selected to be the Stirling system integrator to optimize their convertor and system interfaces designs. Glenn's Thermo-Mechanical Systems Branch provides Stirling technology expertise under a Space Act Agreement with the Department of Energy. Additional vibration testing by Glenn's Structural Systems Dynamics Branch is planned to continue to demonstrate the Stirling power system's vibration capability as its technology and flight system designs progress.

  13. Advances in Frozen Ground Studies and Understanding its Role in the Hydrological Cycle

    NASA Astrophysics Data System (ADS)

    Zhang, T.

    2004-05-01

    Significant advances in frozen ground studies have been achieved over the past several decades. Knowledge and information on frozen ground would improve our understanding in local, regional, and global water cycle over the cold regions/cold seasons. Permafrost regions occupy approximately 24 percent of the land area in the Northern Hemisphere. The total volume of the excess ground ice contained in the ice-rich permafrost ranges from about 10,800 to 35,460 cubic kilometers or about 2.7 to 8.8 cm sea-level equivalent. Permafrost limits the amount of subsurface water storage and infiltration that can occur, leading to wet soils and standing surface water, unusual for a region with limited precipitation. Observational evidence indicates that permafrost warming and thawing in the Northern Hemisphere have occurred over the past several decades. Active layer thickness has increased and depth of seasonally frozen ground has decreased significantly in the Russian Arctic and Subarctic. Thickening of the active layer and melting of the excess ground ice may partly contribute to the increase of runoff over the Russian Arctic drainage basin. Increase in active layer thickness may also delay the active layer freeze-up date, possibly leading to the increase in winter river runoff. On average, nearly 50 percent of the land surface in the Northern Hemisphere experiences freeze/thaw cycles that last from a few days to several months with thickness up to several meters. The existence of a thin frozen layer near the surface essentially decouples moisture exchange between the atmosphere and deeper soils. Knowing whether the soil is frozen is important in predicting spring surface runoff and soil moisture reserve in northern United States. Coupling of soil freezing and thawing processes into the hydrological model improves the model prediction on river runoff significantly. The timing, duration, areal extent,frequency, and thickness of the near-surface soil freeze/thaw cycle have

  14. Birds do it, bees do it, we do it: contributions of theoretical modelling to understanding the shape of ageing across the tree of life.

    PubMed

    Baudisch, Annette

    2012-01-01

    Organisms of different species age differently. Current theory explains why life should get worse, i.e. why patterns of increasing risk of death should evolve. However, for some species the risk of death remains constant or even falls with advancing age. Evolutionary theory to explain the observed diversity of shapes of ageing is lacking. Theoretical models can provide insights into this diversity. Comparing assumptions of models that find increasing mortality patterns with models that find a variety of patterns, including constant and falling mortality over age, I identify conditions that licence constant or negative shapes of ageing. The results suggest that patterns of improvement and maintenance over age emerge when models potentially allow organisms to (1) escape the 'damage ratchet', (2) achieve maintenance and repair in parallel, (3) face increasing future reproductive potential and (4) incorporate flexible trade-offs. With these insights, theoretical models contribute to hypotheses about which species may follow life history strategies of negligible or negative ageing.

  15. Advancing insights into methods for studying environment-health relationships: a multidisciplinary approach to understanding Legionnaires' disease.

    PubMed

    Dunn, Christine E; Bhopal, Raj S; Cockings, Samantha; Walker, David; Rowlingson, Barry; Diggle, Peter

    2007-09-01

    Recent years have witnessed important advances in the analysis of spatially referenced health data. This paper uses GIS and point pattern modelling to address previously unanswered questions regarding the spatial epidemiology of Legionnaires' disease. We demonstrate a distance effect for proximity of residence to cooling towers; mixed support for a directional effect; and some evidence relating to multiple sources. In uncovering complex conceptual and technical problems in the spatial modelling of infection risk we also extended the limits of existing point pattern techniques. We advocate further multidisciplinary research to advance methodological developments for understanding spatial environment-health relationships.

  16. Understanding diagnosis and management of dementia and guideline implementation in general practice: a qualitative study using the theoretical domains framework

    PubMed Central

    2014-01-01

    Background Dementia is a growing problem, causing substantial burden for patients, their families, and society. General practitioners (GPs) play an important role in diagnosing and managing dementia; however, there are gaps between recommended and current practice. The aim of this study was to explore GPs’ reported practice in diagnosing and managing dementia and to describe, in theoretical terms, the proposed explanations for practice that was and was not consistent with evidence-based guidelines. Methods Semi-structured interviews were conducted with GPs in Victoria, Australia. The Theoretical Domains Framework (TDF) guided data collection and analysis. Interviews explored the factors hindering and enabling achievement of 13 recommended behaviours. Data were analysed using content and thematic analysis. This paper presents an in-depth description of the factors influencing two behaviours, assessing co-morbid depression using a validated tool, and conducting a formal cognitive assessment using a validated scale. Results A total of 30 GPs were interviewed. Most GPs reported that they did not assess for co-morbid depression using a validated tool as per recommended guidance. Barriers included the belief that depression can be adequately assessed using general clinical indicators and that validated tools provide little additional information (theoretical domain of ‘Beliefs about consequences’); discomfort in using validated tools (‘Emotion’), possibly due to limited training and confidence (‘Skills’; ‘Beliefs about capabilities’); limited awareness of the need for, and forgetting to conduct, a depression assessment (‘Knowledge’; ‘Memory, attention and decision processes’). Most reported practising in a manner consistent with the recommendation that a formal cognitive assessment using a validated scale be undertaken. Key factors enabling this were having an awareness of the need to conduct a cognitive assessment (‘Knowledge’); possessing

  17. Understanding diagnosis and management of dementia and guideline implementation in general practice: a qualitative study using the theoretical domains framework.

    PubMed

    Murphy, Kerry; O'Connor, Denise A; Browning, Colette J; French, Simon D; Michie, Susan; Francis, Jill J; Russell, Grant M; Workman, Barbara; Flicker, Leon; Eccles, Martin P; Green, Sally E

    2014-03-03

    Dementia is a growing problem, causing substantial burden for patients, their families, and society. General practitioners (GPs) play an important role in diagnosing and managing dementia; however, there are gaps between recommended and current practice. The aim of this study was to explore GPs' reported practice in diagnosing and managing dementia and to describe, in theoretical terms, the proposed explanations for practice that was and was not consistent with evidence-based guidelines. Semi-structured interviews were conducted with GPs in Victoria, Australia. The Theoretical Domains Framework (TDF) guided data collection and analysis. Interviews explored the factors hindering and enabling achievement of 13 recommended behaviours. Data were analysed using content and thematic analysis. This paper presents an in-depth description of the factors influencing two behaviours, assessing co-morbid depression using a validated tool, and conducting a formal cognitive assessment using a validated scale. A total of 30 GPs were interviewed. Most GPs reported that they did not assess for co-morbid depression using a validated tool as per recommended guidance. Barriers included the belief that depression can be adequately assessed using general clinical indicators and that validated tools provide little additional information (theoretical domain of 'Beliefs about consequences'); discomfort in using validated tools ('Emotion'), possibly due to limited training and confidence ('Skills'; 'Beliefs about capabilities'); limited awareness of the need for, and forgetting to conduct, a depression assessment ('Knowledge'; 'Memory, attention and decision processes'). Most reported practising in a manner consistent with the recommendation that a formal cognitive assessment using a validated scale be undertaken. Key factors enabling this were having an awareness of the need to conduct a cognitive assessment ('Knowledge'); possessing the necessary skills and confidence ('Skills'; 'Beliefs

  18. Sarcasm and Advanced Theory of Mind Understanding in Children and Adults with Prelingual Deafness

    ERIC Educational Resources Information Center

    O'Reilly, Karin; Peterson, Candida C.; Wellman, Henry M.

    2014-01-01

    Two studies addressed key theoretical debates in theory of mind (ToM) development by comparing (a) deaf native signers (n = 18), (b) deaf late signers (n = 59), and (c) age-matched hearing persons (n = 74) in childhood (Study 1: n = 81) and adulthood (Study 2: n = 70) on tests of first- and second-order false belief and conversational sarcasm.…

  19. Sarcasm and Advanced Theory of Mind Understanding in Children and Adults with Prelingual Deafness

    ERIC Educational Resources Information Center

    O'Reilly, Karin; Peterson, Candida C.; Wellman, Henry M.

    2014-01-01

    Two studies addressed key theoretical debates in theory of mind (ToM) development by comparing (a) deaf native signers (n = 18), (b) deaf late signers (n = 59), and (c) age-matched hearing persons (n = 74) in childhood (Study 1: n = 81) and adulthood (Study 2: n = 70) on tests of first- and second-order false belief and conversational sarcasm.…

  20. Towards integrated approaches to advance understanding of ecohydrological systems across scales

    NASA Astrophysics Data System (ADS)

    Tetzlaff, Doerthe; Soulsby, Chris

    2016-04-01

    It is increasingly recognised that the processes and connections in our landscapes are influencing the functioning of aquatic ecosystems. Fundamental scientific understanding of the functioning of both aquatic and terrestrial ecosystems is required for an integrated and sustainable management of landscapes and riverscapes to maintain their ecosystem services and biological integrity at multiple scales. This talk will show how the interactions and feedbacks in ecohydrological systems can be quantitatively assessed through a number of novel, integrated approaches. Importantly, this talk will discuss the need to understand the role of vegetation on water partitioning at the terrestrial and aquatic interface. Terrestrial and aquatic ecosystems are interacting at every scale level and cross-scale investigations are extremely useful to gain an integrated understanding of ecohydrological systems. Environmental tracers are valuable tools to understand the functioning of ecohydrological systems at the landscape scale in terms of understand flow paths, sources of water and associated biogeochemical interactions. Extensive empirical studies were conducted at the plot and hillslope scale to understand ecohydrological systems, and in particular, soil-vegetation-water interlinkages. This empirically based understanding was then integrated into spatially distributed, tracer-aided models to understand mixing of water, flows to the stream and water age distribution at the catchment scale. Finally, remote sensing techniques were used to integrate empirically based findings and to extrapolate system understanding to cross-regional scales, specifically in terms of studying hydroclimatic variability, vegetation dynamics and consequent changes of plant water use and water partitioning.

  1. Recent advances in understanding/management of non-alcoholic steatohepatitis

    PubMed Central

    Pacana, Tommy

    2015-01-01

    Non-alcoholic steatohepatitis (NASH) can lead to advanced fibrosis, hepatocellular carcinoma, and end-stage liver disease requiring liver transplantation. A myriad of pathways and genetic influence contribute to NASH pathogenesis and liver disease progression. Diagnosing patients with NASH and advanced fibrosis is critical prior to treatment and prognostication. There has been ongoing interest in developing non-invasive biomarkers and tools for identifying NASH and advanced fibrosis. To date, there has been no approved therapy for NASH. Recently, the FLINT (Farnesoid X Receptor [FXR] Ligand Obeticholic Acid in NASH Treatment) trial provided promising results of the efficacy of obeticholic acid, a farnesoid X receptor agonist, in improving histological features of NASH and fibrosis. Long-term studies are needed to assess the safety of obeticholic acid and its effects on liver- and cardiovascular-related outcomes. PMID:25926979

  2. Design and fundamental understanding of Minimum Quantity Lubrication (MQL) assisted grinding using advanced nanolubricants

    NASA Astrophysics Data System (ADS)

    Kalita, Parash

    Abrasive grinding is widely used across manufacturing industry for finishing parts and components requiring smooth superficial textures and precise dimensional tolerances and accuracy. Unlike any other machining operations, the complex thermo-mechanical processes during grinding produce excessive friction-induced energy consumption, heat, and intense contact seizures. Lubrication and cooling from grinding fluids is crucial in minimizing the deleterious effects of friction and heat to maximize the output part quality and process efficiency. The conventional flood grinding approach of an uneconomical application of large quantities of chemically active fluids has been found ineffective to provide sufficient lubrication and produces waste streams and pollutants that are hazardous to human health and environment. Application of Minimum Quantity Lubrication (MQL) that cuts the volumetric fluid consumption by 3-4 orders of magnitude have been extensively researched in grinding as a high-productivity and environmentally-sustainable alternative to the conventional flood method. However, the lubrication performance and productivity of MQL technique with current fluids has been critically challenged by the extreme thermo-mechanical conditions of abrasive grinding. In this research, an MQL system based on advanced nanolubricants has been proposed to address the current thermo-mechanical challenges of MQL grinding and improve its productivity. The nanolubricants were composed of inorganic Molybdenum Disulphide nanoparticles (≈ 200 nm) intercalated with organic macromolecules of EP/AW property, dispersed in straight (base) oils---mineral-based paraffin and vegetable-based soybean oil. After feasibility investigations into the grindability of cast iron using MQL with nanolubricants, this research focused on the fundamental understanding of tribological behavior and lubricating mechanisms of nanolubricants as a method to improve the productivity of MQL-assisted surface grinding

  3. Recent advances in understanding the biomolecular basis of chronic beryllium disease: a review.

    PubMed

    McCleskey, T Mark; Buchner, Virginia; Field, R William; Scott, Brian L

    2009-01-01

    In this review we summarize the work conducted over the past decade that has advanced our knowledge of pulmonary diseases associated with exposure to beryllium that has provided a molecular-based understanding of the chemistry, immunopathology, and immunogenetics of beryllium toxicity. Beryllium is a strong and lightweight metal that generates and reflects neutrons, resists corrosion, is transparent to X-rays, and conducts electricity. Beryllium is one of the most toxic elements on the periodic table, eliciting in susceptible humans (a) an allergic immune response known as beryllium sensitization (BeS); (b) acute beryllium disease, an acutely toxic, pneumonitis-like lung condition resulting from exposure to high beryllium concentrations that are rarely seen in modern industry; and (c) chronic beryllium disease (CBD) following either high or very low levels of exposure. Because of its exceptional strength, stability, and heat-absorbing capability, beryllium is used in many important technologies in the modern world. In the early 1940s, beryllium was recognized as posing an occupational hazard in manufacturing and production settings. Although acute beryllium disease is now rare, beryllium is an insidious poison with a latent toxicity and the risk of developing CBD persists. Chronic beryllium disease-a systemic granulomatous lung disorder caused by a specific delayed immune response to beryllium within a few months to several decades after exposure-has been called the "unrecognized epidemic". Although not a disease in itself, BeS, the innate immune response to beryllium identified by an abnormal beryllium lymphocyte proliferation test result, is a population-based predictor of CBD. Genetic susceptibility to CBD is associated with alleles of the major histocompatibility gene, human leukocyte antigen DP (HLA-DP) containing glutamic acid at the 69th position of the beta chain (HLA-DPbeta-E69). Other genes are likely to be involved in the disease process, and research on

  4. Advances in Learning and Behavioral Disabilities. Volume 10. Part A: Theoretical Perspectives [and] Part B: Intervention Research.

    ERIC Educational Resources Information Center

    Scruggs, Thomas E., Ed.; Mastropieri, Margo A., Ed.

    This two-volume set presents 11 papers on the state of the art in learning and behavioral disabilities, the first volume, Part A, includes 6 papers providing theoretical perspectives and, the second volume, Part B, includes 5 papers on intervention research. The theoretical papers are: "Defining Emotional or Behavioral Disorders: Divergence…

  5. Advances toward More Efficient Targeted Delivery of Nanoparticles in Vivo: Understanding Interactions between Nanoparticles and Cells.

    PubMed

    Polo, Ester; Collado, Manuel; Pelaz, Beatriz; Del Pino, Pablo

    2017-03-07

    In this Perspective, we describe current challenges and recent advances in efficient delivery and targeting of nanoparticles in vivo. We discuss cancer therapy, nanoparticle-biomolecule interactions, nanoparticle trafficking in cells, and triggers and responses to nanoparticle-cell interactions. No matter which functionalization strategy to target cancer is chosen, passive or active targeting, more than 99% of the nanoparticles administered in vivo end up in the mononuclear phagocytic system, mainly sequestered by macrophages. Comprehensive studies, such as the one reported by MacParland et al. in this issue of ACS Nano, will help to close the gap between nanotechnology-based drug-delivery solutions and advanced medicinal products.

  6. School Drama and Representations of War and Terror--Some Theoretical Approaches to Understanding Learning in Drama in Troubled Times

    ERIC Educational Resources Information Center

    Franks, Anton

    2008-01-01

    The argument here proceeds from an understanding that learning in drama is about participating in forms of cultural production whilst simultaneously engaging thought and feeling to make sense of aspects of contemporary life. In contemporary culture, acts of war and terror are mediated through television and digitised media and are thereby given…

  7. School Drama and Representations of War and Terror--Some Theoretical Approaches to Understanding Learning in Drama in Troubled Times

    ERIC Educational Resources Information Center

    Franks, Anton

    2008-01-01

    The argument here proceeds from an understanding that learning in drama is about participating in forms of cultural production whilst simultaneously engaging thought and feeling to make sense of aspects of contemporary life. In contemporary culture, acts of war and terror are mediated through television and digitised media and are thereby given…

  8. Advancing Understanding Using Nonaka's Model of Knowledge Creation and Problem-Based Learning

    ERIC Educational Resources Information Center

    Tee, Meng Yew; Lee, Shuh Shing

    2013-01-01

    Nonaka's model of knowledge creation can provide guidance for designing learning environments and activities. However, Bereiter is critical of the model because it does not address whether understanding is deepened in the process of socialization, externalization, combination and internalization. To address this issue of understanding, this…

  9. Advancing Understanding Using Nonaka's Model of Knowledge Creation and Problem-Based Learning

    ERIC Educational Resources Information Center

    Tee, Meng Yew; Lee, Shuh Shing

    2013-01-01

    Nonaka's model of knowledge creation can provide guidance for designing learning environments and activities. However, Bereiter is critical of the model because it does not address whether understanding is deepened in the process of socialization, externalization, combination and internalization. To address this issue of understanding, this…

  10. Understanding Fluorescence Measurements through a Guided-Inquiry and Discovery Experiment in Advanced Analytical Laboratory

    ERIC Educational Resources Information Center

    Wilczek-Vera, Grazyna; Salin, Eric Dunbar

    2011-01-01

    An experiment on fluorescence spectroscopy suitable for an advanced analytical laboratory is presented. Its conceptual development used a combination of the expository and discovery styles. The "learn-as-you-go" and direct "hands-on" methodology applied ensures an active role for a student in the process of visualization and discovery of concepts.…

  11. Building a collaborative network to understand regional forest dynamics and advance forestry initiatives in the Caribbean

    Treesearch

    Grizelle Gonzalez; Tamara Heartsill Scalley

    2016-01-01

    Herein we provide concluding remarks drawn from and inspired by the discussions of the 5 working groups of the 16th Caribbean Foresters Meeting (CFM) about the needs, challenges, and recommendations to advance forestry in the Caribbean region. We also list key considerations and potential future research directions as presented in the various manuscripts contained in...

  12. Advances in Modern Botnet Understanding and the Accurate Enumeration of Infected Hosts

    ERIC Educational Resources Information Center

    Nunnery, Christopher Edward

    2011-01-01

    Botnets remain a potent threat due to evolving modern architectures, inadequate remediation methods, and inaccurate measurement techniques. In response, this research exposes the architectures and operations of two advanced botnets, techniques to enumerate infected hosts, and pursues the scientific refinement of infected-host enumeration data by…

  13. Understanding Fluorescence Measurements through a Guided-Inquiry and Discovery Experiment in Advanced Analytical Laboratory

    ERIC Educational Resources Information Center

    Wilczek-Vera, Grazyna; Salin, Eric Dunbar

    2011-01-01

    An experiment on fluorescence spectroscopy suitable for an advanced analytical laboratory is presented. Its conceptual development used a combination of the expository and discovery styles. The "learn-as-you-go" and direct "hands-on" methodology applied ensures an active role for a student in the process of visualization and discovery of concepts.…

  14. Annual Research Review: Impact of Advances in Genetics in Understanding Developmental Psychopathology

    ERIC Educational Resources Information Center

    Addington, Anjene M.; Rapoport, Judith L.

    2012-01-01

    It was hoped that diagnostic guidelines for, and treatment of, child psychiatric disorders in DSM-5 would be informed by the wealth of clinical genetic research related to neurodevelopmental disorders. In spite of remarkable advances in genetic technology, this has not been the case. Candidate gene, genome-wide association, and rare copy number…

  15. Annual Research Review: Impact of Advances in Genetics in Understanding Developmental Psychopathology

    ERIC Educational Resources Information Center

    Addington, Anjene M.; Rapoport, Judith L.

    2012-01-01

    It was hoped that diagnostic guidelines for, and treatment of, child psychiatric disorders in DSM-5 would be informed by the wealth of clinical genetic research related to neurodevelopmental disorders. In spite of remarkable advances in genetic technology, this has not been the case. Candidate gene, genome-wide association, and rare copy number…

  16. Advances in Modern Botnet Understanding and the Accurate Enumeration of Infected Hosts

    ERIC Educational Resources Information Center

    Nunnery, Christopher Edward

    2011-01-01

    Botnets remain a potent threat due to evolving modern architectures, inadequate remediation methods, and inaccurate measurement techniques. In response, this research exposes the architectures and operations of two advanced botnets, techniques to enumerate infected hosts, and pursues the scientific refinement of infected-host enumeration data by…

  17. Information-Theoretic Approach May Shed a Light to a Better Understanding and Sustaining the Integrity of Ecological-Societal Systems under Changing Climate

    NASA Astrophysics Data System (ADS)

    Kim, J.

    2016-12-01

    Considering high levels of uncertainty, epistemological conflicts over facts and values, and a sense of urgency, normal paradigm-driven science will be insufficient to mobilize people and nation toward sustainability. The conceptual framework to bridge the societal system dynamics with that of natural ecosystems in which humanity operates remains deficient. The key to understanding their coevolution is to understand `self-organization.' Information-theoretic approach may shed a light to provide a potential framework which enables not only to bridge human and nature but also to generate useful knowledge for understanding and sustaining the integrity of ecological-societal systems. How can information theory help understand the interface between ecological systems and social systems? How to delineate self-organizing processes and ensure them to fulfil sustainability? How to evaluate the flow of information from data through models to decision-makers? These are the core questions posed by sustainability science in which visioneering (i.e., the engineering of vision) is an essential framework. Yet, visioneering has neither quantitative measure nor information theoretic framework to work with and teach. This presentation is an attempt to accommodate the framework of self-organizing hierarchical open systems with visioneering into a common information-theoretic framework. A case study is presented with the UN/FAO's communal vision of climate-smart agriculture (CSA) which pursues a trilemma of efficiency, mitigation, and resilience. Challenges of delineating and facilitating self-organizing systems are discussed using transdisciplinary toold such as complex systems thinking, dynamic process network analysis and multi-agent systems modeling. Acknowledgments: This study was supported by the Korea Meteorological Administration Research and Development Program under Grant KMA-2012-0001-A (WISE project).

  18. Toward understanding the dissociation of I2 in chemical oxygen-iodine lasers: Combined experimental and theoretical studies

    NASA Astrophysics Data System (ADS)

    Waichman, K.; Rybalkin, V.; Katz, A.; Dahan, Z.; Barmashenko, B. D.; Rosenwaks, S.

    2007-07-01

    The dissociation of I2 molecules at the optical axis of a supersonic chemical oxygen-iodine laser (COIL) was studied via detailed measurements and three-dimensional computational fluid dynamics calculations. The measurements, briefly reported in a recent paper [Rybalkin et al., Appl. Phys. Lett. 89, 021115 (2006)] and reanalyzed in detail here, revealed that the number N of consumed O2(aΔg1) molecules per dissociated I2 molecule depends on the experimental conditions: it is 4.5±0.4 for typical conditions and I2 densities applied for optimal operation of the COIL but increases at lower I2 densities. Comparing the measurements and the calculations enabled critical examination of previously proposed dissociation mechanisms and suggestion of a mechanism consistent with the experimental and theoretical results obtained in a supersonic COIL for the gain, temperature, I2 dissociation fraction, and N at the optical axis. The suggested mechanism combines the recent scheme of Azyazov and Heaven [AIAA J. 44, 1593 (2006)], where I2(A'Π2u3), I2(AΠ1u3), and O2(aΔg1,v) are significant dissociation intermediates, with the "standard" chain branching mechanism of Heidner III et al. [J. Phys. Chem. 87, 2348 (1983)], involving I(P1/22) and I2(XΣg +1,v).

  19. Understanding regioselective cleavage in peptide hydrolysis by a palladium(II) aqua complex: a theoretical point of view.

    PubMed

    Yeguas, Violeta; Campomanes, Pablo; López, Ramón; Díaz, Natalia; Suárez, Dimas

    2010-07-01

    Hydrolytic cleavage of the oligopeptides Ace-Ala-Lys-Tyr-Gly approximately Gly-Met-Ala-Ala-Arg-Ala and Ace-Lys-Gly-Gly-Ala-Gly approximately Pro-Met-Ala-Ala-Arg-Gly by [Pd(H(2)O)(4)](2+) was theoretically investigated by using molecular dynamics simulations and quantum mechanical calculations. The Pd anchorage to the peptide sequence is crucial to provoke the cleavage of the second bond upstream from the anchored methionine. For both cases, the most favorable reaction mechanism is a three-step route. The first step coincides with the experimental suggestion found for the Gly approximately Pro-Met sequence on a cleavage caused by an external attack of a water molecule to a complex in trans conformation of the scissile Gly approximately Gly and Gly approximately Pro peptide bonds. However, our results uncover the important role played by the presence of a Pd-coordinated water molecule, which simultaneously interacts with the carbonyl oxygen atom of the Gly amino acid in the Gly approximately Gly and Gly approximately Pro bonds. In accordance with experimental facts, the rise of the hydrolysis reaction rate when the Pro amino acid is located in the scissile peptide bond was also corroborated. The findings obtained at a molecular level from the present computations not only are relevant to rationalize the previously reported experiments but also could be of importance in designing new Pd(II) complexes for the regioselective cleavage of peptides and proteins.

  20. 'It's like taking a bit of masculinity away from you': towards a theoretical understanding of men's experiences of infertility.

    PubMed

    Dolan, Alan; Lomas, Tim; Ghobara, Tarek; Hartshorne, Geraldine

    2017-07-01

    In the UK, nearly half of all cases of infertility involve a 'male-factor'. Yet, little empirical work has explored how men as men negotiate this terrain. Three interrelated concepts; 'hegemonic masculinity', 'embodied masculinity' and the linkages between 'masculinities' and male help-seeking, provide the theoretical framework that guided a qualitative study conducted with 22 men experiencing infertility. The paper explores men's propensity to delay their help-seeking in relation to infertility despite their desire for children. It also demonstrates how, in the context of infertility, the male body can be defined as both a failed entity in itself (unable to father a child) and a subordinated social entity (unable to measure up to hegemonic ideals) that characterises men's masculine identities. The paper also illustrates how men appear willing to accept responsibility for their infertility and adopt aspects of hitherto subordinate masculine practice. This does not, however, constitute the total unravelling of well understood and accepted expressions of masculinity. Finally, the paper demonstrates how infertility is perceived as having the potential to fracture current and even future relationships. Moreover, regardless of how well men measured up to other hegemonic ideals, ultimately they can do little to counteract the threat of other (fertile) men. © 2017 The Authors. Sociology of Health & Illness published by John Wiley & Sons Ltd on behalf of Foundation for SHIL.

  1. Understanding advanced theory of mind and empathy in high-functioning adults with autism spectrum disorder.

    PubMed

    Mathersul, Danielle; McDonald, Skye; Rushby, Jacqueline A

    2013-01-01

    It has been argued that higher functioning individuals with autism spectrum disorders (ASDs) have specific deficits in advanced but not simple theory of mind (ToM), yet the questionable ecological validity of some tasks reduces the strength of this assumption. The present study employed The Awareness of Social Inference Test (TASIT), which uses video vignettes to assess comprehension of subtle conversational inferences (sarcasm, lies/deception). Given the proposed relationships between advanced ToM and cognitive and affective empathy, these associations were also investigated. As expected, the high-functioning adults with ASDs demonstrated specific deficits in comprehending the beliefs, intentions, and meaning of nonliteral expressions. They also had significantly lower cognitive and affective empathy. Cognitive empathy was related to ToM and group membership whereas affective empathy was only related to group membership.

  2. Satellite soil moisture for advancing our understanding of earth system processes and climate change

    NASA Astrophysics Data System (ADS)

    Dorigo, Wouter; de Jeu, Richard

    2016-06-01

    Soil moisture products obtained from active and passive microwave satellites have reached maturity during the last decade (De Jeu and Dorigo, 2016): On the one hand, research algorithms that were initially applied to sensors designed for other purposes, e.g., for measuring wind speed (e.g. the Advanced Scatterometer (ASCAT)), sea ice, or atmospheric parameters (e.g. the TRMM Microwave Imager (TMI) and the Advanced Microwave Scanning Radiometer - Earth Observing System AMSR-E), have developed into fully operational products. On the other hand, dedicated soil moisture satellite missions were designed and launched by ESA (the Soil Moisture Ocean Salinity (SMOS) mission) and NASA (the Soil Moisture Active Passive (SMAP) mission).

  3. Advances in understanding ventromedial prefrontal function: the accountant joins the executive.

    PubMed

    Fellows, Lesley K

    2007-03-27

    Studies of the brain basis of decision-making and economic behavior are providing a new perspective on the organization and functions of human prefrontal cortex. This line of inquiry has focused particularly on the ventral and medial portions of prefrontal cortex, arguably the most enigmatic regions of the "enigmatic frontal lobes." This review highlights recent advances in the cognitive neuroscience of decision making and neuroeconomics and discusses how these findings can inform clinical thinking about frontal lobe dysfunction.

  4. A cross-age study of students' conceptual understanding of interdependency in seed dispersal, pollination, and food chains using a constructivist theoretical framework

    NASA Astrophysics Data System (ADS)

    Smith, Shirley Mccraw

    2003-06-01

    The purpose of this research was to investigate students' understanding of interdependency across grade levels. Interdependency concepts selected for this study included food chains, pollination, and seed dispersal. Children's everyday concepts and scientific concepts across grade levels represented the focus of conceptual understanding. The researcher interviewed a total of 24 students across grade levels, six students each from grades 3, 7, and 10, and 6 college students. Data were collected by means of interviews and card sorts. A constructivist theoretical framework formed the groundwork for presenting the focus of this study and for interpreting the results of the interview data. Results were analyzed on the basis of identifying student responses to interview questions as either everyday concepts or as scientific concepts, along with transition through the zone of proximal development (ZPD) by mediation, as developed by Vygotsky. Results revealed that children across grade levels vary in their everyday and scientific understanding of the three interdependency concepts. Results for seed dispersal showed little evidence of understanding for grade 3, that is, seed dispersal was not within the zone of proximal development (ZPD) for grade 3 students. Students in grades 7 and 10 showed a developing transition within the zone of proximal development from everyday to scientific understanding, and college students demonstrated scientific understanding of seed dispersal. For pollination and food chains, results showed that grades 3, 7, and 10 were in transition from everyday to scientific understanding, and all college students demonstrated scientific understanding. The seed dispersal concept proved more complex than pollination and food chains. The findings of this study have implications for classroom teachers. By understanding the dynamic nature of the ZPD continuum for students, teachers can plan instruction to meet the needs of each student.

  5. Millimeter-wave imaging of magnetic fusion plasmas: technology innovations advancing physics understanding

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Tobias, B.; Chang, Y.-T.; Yu, J.-H.; Li, M.; Hu, F.; Chen, M.; Mamidanna, M.; Phan, T.; Pham, A.-V.; Gu, J.; Liu, X.; Zhu, Y.; Domier, C. W.; Shi, L.; Valeo, E.; Kramer, G. J.; Kuwahara, D.; Nagayama, Y.; Mase, A.; Luhmann, N. C., Jr.

    2017-07-01

    Electron cyclotron emission (ECE) imaging is a passive radiometric technique that measures electron temperature fluctuations; and microwave imaging reflectometry (MIR) is an active radar imaging technique that measures electron density fluctuations. Microwave imaging diagnostic instruments employing these techniques have made important contributions to fusion science and have been adopted at major fusion facilities worldwide including DIII-D, EAST, ASDEX Upgrade, HL-2A, KSTAR, LHD, and J-TEXT. In this paper, we describe the development status of three major technological advancements: custom mm-wave integrated circuits (ICs), digital beamforming (DBF), and synthetic diagnostic modeling (SDM). These have the potential to greatly advance microwave fusion plasma imaging, enabling compact and low-noise transceiver systems with real-time, fast tracking ability to address critical fusion physics issues, including ELM suppression and disruptions in the ITER baseline scenario, naturally ELM-free states such as QH-mode, and energetic particle confinement (i.e. Alfvén eigenmode stability) in high-performance regimes that include steady-state and advanced tokamak scenarios. Furthermore, these systems are fully compatible with today’s most challenging non-inductive heating and current drive systems and capable of operating in harsh environments, making them the ideal approach for diagnosing long-pulse and steady-state tokamaks.

  6. Understanding the colloidal dispersion stability of 1D and 2D materials: Perspectives from molecular simulations and theoretical modeling.

    PubMed

    Lin, Shangchao; Shih, Chih-Jen; Sresht, Vishnu; Govind Rajan, Ananth; Strano, Michael S; Blankschtein, Daniel

    2017-06-01

    The colloidal dispersion stability of 1D and 2D materials in the liquid phase is critical for scalable nano-manufacturing, chemical modification, composites production, and deployment as conductive inks or nanofluids. Here, we review recent computational and theoretical studies carried out by our group to model the dispersion stability of 1D and 2D materials, including single-walled carbon nanotubes, graphene, and graphene oxide in aqueous surfactant solutions or organic solvents. All-atomistic (AA) molecular dynamics (MD) simulations can probe the molecular level details of the adsorption morphology of surfactants and solvents around these materials, as well as quantify the interaction energy between the nanomaterials mediated by surfactants or solvents. Utilizing concepts from reaction kinetics and diffusion, one can directly predict the rate constants for the aggregation kinetics and dispersion life times using MD outputs. Furthermore, the use of coarse-grained (CG) MD simulations allows quantitative prediction of surfactant adsorption isotherms. Combined with the Poisson-Boltzmann equation, the Langmuir isotherm, and the DLVO theory, one can directly use CGMD outputs to: (i) predict electrostatic potentials around the nanomaterial, (ii) correlate surfactant surface coverages with surfactant concentrations in the bulk dispersion medium, and (iii) determine energy barriers against coagulation. Finally, we discuss challenges associated with studying emerging 2D materials, such as, hexagonal boron nitride (h-BN), phosphorene, and transition metal dichalcogenides (TMDCs), including molybdenum disulfide (MoS2). An outlook is provided to address these challenges with plans to develop force-field parameters for MD simulations to enable predictive modeling of emerging 2D materials in the liquid phase. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Korean preschoolers' advanced inhibitory control and its relation to other executive skills and mental state understanding.

    PubMed

    Oh, Seungmi; Lewis, Charlie

    2008-01-01

    This study assessed executive function and mental state understanding in Korean preschoolers. In Experiment 1, forty 3.5- and 4-year-old Koreans showed ceiling performance on inhibition and switching measures, although their performance on working memory and false belief was comparable to that of Western children. Experiment 2 revealed a similar advantage in a sample of seventy-six 3- and 4-year-old Koreans compared with sixty-four age-matched British children. Korean children younger than 3.5 years of age showed ceiling effects on some inhibition measures despite more stringent protocols and the link between executive function and mental state understanding was not as strong as in the British sample. The results raise key questions about the nature and development of the executive system and its relation to social understanding.

  8. Theoretical understanding on band engineering of Mn-doped lead chalcogenides PbX (X = Te, Se, S).

    PubMed

    Tan, Xiaojian; Shao, Hezhu; Hu, Tianqi; Liu, Guo-Qiang; Ren, Shang-Fen

    2015-03-11

    Electronic structures of Mn-doped PbX (X = Te, Se, S) are investigated by first-principles calculations. It is found that the Mn-doping in PbTe enlarges the band gap and increases the valence bands degeneracy, showing good agreement with experimental measurements. This band adjustment is demonstrated to be from the anti-bonding of Te-p and Mn-d orbitals. Along the series of PbTe-PbSe-PbS, the band modification of Mn-doping undergoes a gradual transition from multiple valence bands type to resonant states type, owing to the downwards shifted anion-p orbitals. This work provides essential understandings on the band engineering of Mn-doped lead chalcogenides thermoelectric materials.

  9. Theoretical understanding on band engineering of Mn-doped lead chalcogenides PbX (X = Te, Se, S)

    NASA Astrophysics Data System (ADS)

    Tan, Xiaojian; Shao, Hezhu; Hu, Tianqi; Liu, Guo-Qiang; Ren, Shang-Fen

    2015-03-01

    Electronic structures of Mn-doped PbX (X = Te, Se, S) are investigated by first-principles calculations. It is found that the Mn-doping in PbTe enlarges the band gap and increases the valence bands degeneracy, showing good agreement with experimental measurements. This band adjustment is demonstrated to be from the anti-bonding of Te-p and Mn-d orbitals. Along the series of PbTe-PbSe-PbS, the band modification of Mn-doping undergoes a gradual transition from multiple valence bands type to resonant states type, owing to the downwards shifted anion-p orbitals. This work provides essential understandings on the band engineering of Mn-doped lead chalcogenides thermoelectric materials.

  10. New test techniques and analytical procedures for understanding the behavior of advanced propellers

    NASA Technical Reports Server (NTRS)

    Stefko, G. L.; Bober, L. J.; Neumann, H. E.

    1983-01-01

    Analytical procedures and experimental techniques were developed to improve the capability to design advanced high speed propellers. Some results from the propeller lifting line and lifting surface aerodynamic analysis codes are compared with propeller force data, probe data and laser velocimeter data. In general, the code comparisons with data indicate good qualitative agreement. A rotating propeller force balance demonstrated good accuracy and reduced test time by 50 percent. Results from three propeller flow visualization techniques are shown which illustrate some of the physical phenomena occurring on these propellers.

  11. Advances in the management and understanding of autoimmune lymphoproliferative syndrome (ALPS).

    PubMed

    Teachey, David T; Seif, Alix E; Grupp, Stephan A

    2010-01-01

    Autoimmune lymphoproliferative syndrome (ALPS) is a disorder of T cell dysregulation caused by defective Fas-mediated apoptosis. Patients with ALPS can develop a myriad of clinical manifestations including lymphadenopathy, hepatosplenomegaly, autoimmunity and increased rates of malignancy. ALPS may be more common that originally thought, and testing for ALPS should be considered in patients with unexplained lymphadenopathy, hepatosplenomegaly, and/or autoimmunity. As the pathophysiology of ALPS is better characterized, a number of targeted therapies are in preclinical development and clinical trials with promising early results. This review describes the clinical and laboratory manifestations found in ALPS patients, as well as the molecular basis for the disease and new advances in treatment.

  12. Advancing the Understanding of ?Emissions from Oil and Natural Gas Production Operations

    EPA Science Inventory

    This presentation describes an EPA effort to improve the understanding of well pad emissions and remote measurement methods, and identify areas where future work is needed. Funded through an R8 RARE, R8, ORD, and OAQPS conducted a two-phase project to explore a novel measuremen...

  13. Advancing the Understanding of Emissions from Oil and Natural Gas Production Operations

    EPA Science Inventory

    This presentation describes an EPA effort to improve the understanding of well pad emissions and remote measurement methods, and identify areas where future work is needed. Funded through an R8 RARE, R8, ORD, and OAQPS conducted a two-phase project to explore a novel measuremen...

  14. Programs and Practices: Students' Historical Understandings in International Baccalaureate, Advanced Placement and Regular World History Courses

    ERIC Educational Resources Information Center

    Ryter, Di

    2015-01-01

    World history has become increasingly important and has often been a required course for high school students in the United States. This multi-case study provides examples and descriptions of students' demonstration of historical understandings. It also includes multiple perspectives and experiences of world history students and teachers, and…

  15. Korean Preschoolers' Advanced Inhibitory Control and Its Relation to Other Executive Skills and Mental State Understanding

    ERIC Educational Resources Information Center

    Oh, Seungmi; Lewis, Charlie

    2008-01-01

    This study assessed executive function and mental state understanding in Korean preschoolers. In Experiment 1, forty 3.5- and 4-year-old Koreans showed ceiling performance on inhibition and switching measures, although their performance on working memory and false belief was comparable to that of Western children. Experiment 2 revealed a similar…

  16. Bridging Identities and Disciplines: Advances and Challenges in Understanding Multiple Identities

    ERIC Educational Resources Information Center

    Phinney, Jean S.

    2008-01-01

    The chapters in this volume address the need for a better understanding of the development of intersecting identities over age and context. The chapters provide valuable insights into the development of identities, particularly group identities. They highlight common processes across identities, such as the role of contrast and comparison and the…

  17. Issues In-Depth: Advancing Understanding of Drug Addiction and Treatment

    ERIC Educational Resources Information Center

    Miller, Roxanne Greitz

    2009-01-01

    While most school districts utilize a drug abuse resistance curriculum, as science teachers, it is our responsibility to understand the science behind drug addiction in order to most effectively educate our students against drug abuse. In the last two decades, increases in scientific technology have permitted significant discoveries surrounding…

  18. Research in the Luquillo Experimental Forest has advanced understanding of tropical forests and resolved management issues

    Treesearch

    A.E. Lugo; T. Heartsill Scalley

    2014-01-01

    Long-term research on the response of wet forests in the Luquillo Experimental Forest (LEF) to natural and anthropogenic disturbances yielded information useful for the management of these forests and to a better understanding of the functioning of tropical forests and how species composition changes under different distrubance regimes. We summarize studies on basal...

  19. Issues In-Depth: Advancing Understanding of Drug Addiction and Treatment

    ERIC Educational Resources Information Center

    Miller, Roxanne Greitz

    2009-01-01

    While most school districts utilize a drug abuse resistance curriculum, as science teachers, it is our responsibility to understand the science behind drug addiction in order to most effectively educate our students against drug abuse. In the last two decades, increases in scientific technology have permitted significant discoveries surrounding…

  20. Recent advances in understanding and preventing human papillomavirus-related disease

    PubMed Central

    Hellner, Karin; Dorrell, Lucy

    2017-01-01

    High-risk human papillomaviruses (hrHPV) are responsible for anogenital and oropharyngeal cancers, which together account for at least 5% of cancers worldwide. Industrialised nations have benefitted from highly effective screening for the prevention of cervical cancer in recent decades, yet this vital intervention remains inaccessible to millions of women in low- and middle-income countries (LMICs), who bear the greatest burden of HPV disease. While there is an urgent need to increase investment in basic health infrastructure and rollout of prophylactic vaccination, there are now unprecedented opportunities to exploit recent scientific and technological advances in screening and treatment of pre-invasive hrHPV lesions and to adapt them for delivery at scale in resource-limited settings. In addition, non-surgical approaches to the treatment of cervical intraepithelial neoplasia and other hrHPV lesions are showing encouraging results in clinical trials of therapeutic vaccines and antiviral agents. Finally, the use of next-generation sequencing to characterise the vaginal microbial environment is beginning to shed light on host factors that may influence the natural history of HPV infections. In this article, we focus on recent advances in these areas and discuss their potential for impact on HPV disease. PMID:28357043

  1. Innovations in performance assessment: a criterion based performance assessment for advanced practice nurses using a synergistic theoretical nursing framework.

    PubMed

    Scarpa, Raymond; Connelly, Patricia E

    2011-01-01

    Health care organizations that employ advanced practice nurses are challenged to evaluate practice at this advanced level. Current evaluation methods tend to inter-mingle basic nursing competencies with competencies found in medical practice and organizational objectives that are typically derived from human resources departments. This article describes the development of a criterion-based job performance assessment for advanced nursing practice using a framework rooted in a nursing theory. A needs analysis; review of the literature, adaptation of nursing's Synergy Model, and input from various stakeholders guided the development of a generic job description. This job description progressed into a criterion-based performance assessment. Construct validity was tested using a questionnaire administered to a convenience sample of 9 practicing advanced practice nurses, 2 nurse executives, 1 PhD nurse educator, and 1 physician. Autonomy, job satisfaction, and quality improvement for advanced practice nurses are fostered by a review process that defines roles and competencies specific to advanced nursing practice. Peer review, a concept contributing to this process is explored as a means to monitor and improve practice.

  2. Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort

    SciTech Connect

    Yan, Fangyong; Lartey, Michael; Damodaran, Krishnan; Albenze, Erik; Thompson, Robert L.; Kim, Jihan; Harancyzk, Maciel; Nulwala, Hunaid B.; Luebke, David R.; Smit, Berend

    2013-01-01

    Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure–property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO{sub 2} solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO{sub 2} capture but has application in many technological fields.

  3. Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort.

    PubMed

    Yan, Fangyong; Lartey, Michael; Damodaran, Krishnan; Albenze, Erik; Thompson, Robert L; Kim, Jihan; Haranczyk, Maciej; Nulwala, Hunaid B; Luebke, David R; Smit, Berend

    2013-03-07

    Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure-property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO(2) solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO(2) capture but has application in many technological fields.

  4. Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort

    SciTech Connect

    Yan, Fangyong; Lartey, Michael; Damodaran, Krishnan; Albenze, Erik; Thompson, Robert L.; Kim, Jihan; Haranczyk, Maciej; Nulwala, Hunaid B.; Luebke, David R.; Smit, Berend

    2013-01-01

    Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure–property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO{sub 2} solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO{sub 2} capture but has application in many technological fields.

  5. Exploring multi/full polarised SAR imagery for understanding surface soil moisture and roughness by using semi-empirical and theoretical models and field experiments

    NASA Astrophysics Data System (ADS)

    Dong, Lu; Marzahn, Philip; Ludwig, Ralf

    2010-05-01

    -range digital photogrammetry for surface roughness retrieval. A semi-empirical model is tested and a theoretical model AIEM is utilised for further understanding. Results demonstrate that the semi-empirical soil moisture retrieval algorithm, which was developed in studies in humid climate conditions, must be carefully adapted to the drier Mediterranean environment. Modifying the approach by incorporating regional field data, led to a considerable improvement of the algorithms performance. In addition, it is found that the current representation of soil surface roughness in the AIEM is insufficient to account for the specific heterogeneities on the field scale. The findings in this study indicate the necessity for future research, which must be extended to a more integrated combination of current sensors, e.g. ENVISAT/ASAR, ALOS/PALSAR and Radarsat-2 imagery and advanced development of soil moisture retrieval model for multi/full polarised radar imagery.

  6. Special issue on the advances in understanding of the North Pacific subtropical front ecosystem

    NASA Astrophysics Data System (ADS)

    McKinnell, Skip; Seki, Michael P.; Ichii, Taro

    2017-01-01

    Subtropical, oligotrophic oceanic gyres are the largest marine ecosystems in the world. They provide important habitat for many higher trophic level species of fish, squid, seabirds, and marine mammals, with some taxa undergoing extensive seasonal migrations between the subtropical frontal region and summer feeding grounds in the subarctic. Knowledge of the structure, variability, and trends of these regions has developed slowly because of their immense size, remote location, and cost of sampling. The first consolidation of the general understanding of the physical nature of the subtropical North Pacific Ocean (and subarctic transition) was published 25 years ago (Roden, 1991) with important information on its relationship to biota added by the now defunct International North Pacific Fisheries Commission (INPFC, 1992; Ito et al., 1993). At that time, a research imperative had arisen from a need by governments to understand the effects of large-scale pelagic driftnet fishing on marine ecosystems (Wetherall, 1991).

  7. State-dependent metabolic partitioning and energy conservation: A theoretical framework for understanding the function of sleep.

    PubMed

    Schmidt, Markus H; Swang, Theodore W; Hamilton, Ian M; Best, Janet A

    2017-01-01

    evolutionary selective advantage for the upregulation of central and peripheral biological processes during sleep, presenting a unifying construct to understand sleep function.

  8. Recent advances in understanding and managing cystic fibrosis transmembrane conductance regulator dysfunction

    PubMed Central

    Alton, Eric W.F.W.

    2015-01-01

    Cystic fibrosis is the most common autosomal recessive genetic disease in Caucasians and has been extensively studied for many decades. The cystic fibrosis transmembrane conductance regulator gene was identified in 1989. It encodes a complex protein which has numerous cellular functions. Our understanding of cystic fibrosis pathophysiology and genetics is constantly expanding and being refined, leading to improved management of the disease and increased life expectancy in affected individuals. PMID:26097737

  9. Integrating Syntax, Semantics, and Discourse DARPA (Defense Advanced Research Projects Agency) Natural Language Understanding Program.

    DTIC Science & Technology

    1987-08-12

    efforts. At the Workshop, Rebecca Passonneau and Francois Lang gave demos of the PUNDIT system doing message processing and demonstrating acquisition of...conference was attended under NSF funding.) Lynette Hirschman and Rebecca Passonneau attended the Message Understanding Conference at NOSC (Naval Ocean...papers. Deborah Dahl presented the paper she co-authored with Martha Palmer and Rebecca Passonneau entitled "Nominalizations in PUNDIT" Rebecca

  10. The Understanding by Design Guide to Advanced Concepts in Creating and Reviewing Units

    ERIC Educational Resources Information Center

    McTighe, Jay; Wiggins, Grant

    2012-01-01

    Regardless of your stage at implementing the design tools and using the improved template for Understanding by Design[R] (UbD), this companion to "The UbD Guide to Creating High-Quality Units" is essential for taking your work to a higher plane. This volume features a set of hands-on modules containing worksheets, models, and self-assessments that…

  11. Recent advances in improvement of forecast skill and understanding climate processes using AIRS Version-5 products

    NASA Astrophysics Data System (ADS)

    Susskind, Joel; Molnar, Gyula; Iredell, Lena; Rosenberg, Robert

    2012-10-01

    The NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC) generates products derived from AIRS/AMSU-A observations, starting from September 2002 when the AIRS instrument became stable, using the AIRS Science Team Version-5 retrieval algorithm. This paper shows results of some of our research using Version-5 products from the points of view of improving forecast skill as well as aiding in the understanding of climate processes.

  12. The Understanding by Design Guide to Advanced Concepts in Creating and Reviewing Units

    ERIC Educational Resources Information Center

    McTighe, Jay; Wiggins, Grant

    2012-01-01

    Regardless of your stage at implementing the design tools and using the improved template for Understanding by Design[R] (UbD), this companion to "The UbD Guide to Creating High-Quality Units" is essential for taking your work to a higher plane. This volume features a set of hands-on modules containing worksheets, models, and self-assessments that…

  13. Recent Advances in Understanding the Reactivity of Energetic Ionic Liquids in Propulsion Applications

    DTIC Science & Technology

    2014-08-12

    enabled the investigation of anion properties such as basicity and nucleophilicity in the condensed phase. Both the basicity and nucleophilicity of the... anion influence the thermal decomposition of ionic liquids and understanding basicity of the anion is important in interpreting hypergolic ignition...Low flammability. – C+A- : 1018 possible combinations of cations and anions . • Hypergolic Ignition involves: – Pre-ignition chemistry- “chemical

  14. Mammalian cell models to advance our understanding of wound healing: a review.

    PubMed

    Vidmar, Jerneja; Chingwaru, Constance; Chingwaru, Walter

    2017-04-01

    Rapid and efficient healing of damaged tissue is critical for the restoration of tissue function and avoidance of tissue defects. Many in vitro cell models have been described for wound healing studies; however, the mechanisms that underlie the process, especially in chronic or complicated wounds, are not fully understood. The identification of cell culture systems that closely simulate the physiology of damaged tissue in vivo is necessary. We describe the cell culture models that have enhanced our understanding, this far, of the wound healing process or have been used in drug discovery. Cell cultures derived from the epithelium, including corneal, renal, intestinal (IEC-8 cells and IEC-6), skin epithelial cells (keratinocytes, fibroblasts, and multipotent mesenchymal stem cells), and the endothelium (human umbilical vein endothelial cells, primary mouse endothelial cells, endodermal stem cells, human mesenchymal stem cells, and corneal endothelial cells) have played a pivotal role toward our understanding of the mechanisms of wound healing. More studies are necessary to develop co-culture cell models which closely simulate the environment of a wound in vivo. Cell culture models are invaluable tools to promote our understanding of the mechanisms that regulate the wound healing process and provide a platform for drug discovery. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Anaerobic fungi (phylum Neocallimastigomycota): advances in understanding their taxonomy, life cycle, ecology, role and biotechnological potential.

    PubMed

    Gruninger, Robert J; Puniya, Anil K; Callaghan, Tony M; Edwards, Joan E; Youssef, Noha; Dagar, Sumit S; Fliegerova, Katerina; Griffith, Gareth W; Forster, Robert; Tsang, Adrian; McAllister, Tim; Elshahed, Mostafa S

    2014-10-01

    Anaerobic fungi (phylum Neocallimastigomycota) inhabit the gastrointestinal tract of mammalian herbivores, where they play an important role in the degradation of plant material. The Neocallimastigomycota represent the earliest diverging lineage of the zoosporic fungi; however, understanding of the relationships of the different taxa (both genera and species) within this phylum is in need of revision. Issues exist with the current approaches used for their identification and classification, and recent evidence suggests the presence of several novel taxa (potential candidate genera) that remain to be characterised. The life cycle and role of anaerobic fungi has been well characterised in the rumen, but not elsewhere in the ruminant alimentary tract. Greater understanding of the 'resistant' phase(s) of their life cycle is needed, as is study of their role and significance in other herbivores. Biotechnological application of anaerobic fungi, and their highly active cellulolytic and hemi-cellulolytic enzymes, has been a rapidly increasing area of research and development in the last decade. The move towards understanding of anaerobic fungi using -omics based (genomic, transcriptomic and proteomic) approaches is starting to yield valuable insights into the unique cellular processes, evolutionary history, metabolic capabilities and adaptations that exist within the Neocallimastigomycota.

  16. Advances in understanding cis regulation of the plant gene with an emphasis on comparative genomics.

    PubMed

    Burgess, Diane G; Xu, Jie; Freeling, Michael

    2015-10-01

    The plant gene model remains largely an extrapolation from animals, with the cis functional unit, the gene, cast as a dynamic looping structure. Molecular genetics with model plants continues to make advances; highlighted here are quantitative-occupancy results from the Arabidopsis thaliana (Arabidopsis) Phytochrome-Interacting bHLH transcription Factors (PIF) quartet. Compared to this complex snapshot, results from chromatin occupancy and other Encyclopedia of DNA Elements (ENCODE)-like approaches increase our transcription factor-motif cognate library, but regulation cannot by itself be inferred from binding. Complementary published Arabidopsis conserved noncoding sequence lists are compared, evaluated, merged, and released. Comparative genomic approaches have identified a cis modifier of a gene's expression-hypothetically, a transposon-based 'rheostat'-that works in all cells, times and places.

  17. Gerontology found me: gaining understanding of advanced practice nurses in geriatrics.

    PubMed

    Campbell-Detrixhe, Dia D; Grassley, Jane S; Zeigler, Vicki L

    2013-10-01

    Examining the meanings of the experiences of advanced practice nurses (APNs) who chose to work with older adults and why they continue to work with this population was the focus of this hermeneutic qualitative research study. Twelve geriatric APNs currently practicing in two South Central states were interviewed using an open-ended interview guide. Using Gadamerian hermeneutics, the researchers identified Gerontology Found Me as the significant expression that reflected the fundamental meaning of the experience as a whole. Four themes emerged that further described the meanings of the participants' personal, educational, and professional experiences: Becoming a Gerontology Nurse, Being a Gerontology Nurse, Belonging to Gerontology, and Bringing Others to Gerontology. This study concluded that APNs' personal and professional experiences were more influential than educational experiences to become geriatric nurses, and having these personal and professional experiences of being in relationship with older individuals further contributed to their choice of gerontology.

  18. Understanding meaning in life interventions in patients with advanced disease: A systematic review and realist synthesis.

    PubMed

    Guerrero-Torrelles, Mariona; Monforte-Royo, Cristina; Rodríguez-Prat, Andrea; Porta-Sales, Josep; Balaguer, Albert

    2017-02-01

    Among patients with advanced disease, meaning in life is thought to enhance well-being, promote coping and improve the tolerance of physical symptoms. It may also act as a buffer against depression and hopelessness. As yet, there has been no synthesis of meaning in life interventions in which contextual factors, procedures and outcomes are described and evaluated. To identify meaning in life interventions implemented in patients with advanced disease and to describe their context, mechanisms and outcomes. Systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and realist synthesis of meaning in life interventions using criteria from the Realist And Meta-narrative Evidence Syntheses: Evolving Standards project. The CINAHL, PsycINFO, PubMed and Web of Science databases were searched. A total of 12 articles were included in the systematic review, corresponding to nine different interventions. Five articles described randomized controlled trials, two were qualitative studies, two were commentaries or reflections, and there was one pre-post evaluation, one exploratory study and one description of a model of care. Analysis of context, mechanisms and outcomes configurations showed that a core component of all the interventions was the interpersonal encounter between patient and therapist, in which sources of meaning were explored and a sense of connectedness was re-established. Meaning in life interventions were associated with clinical benefits on measures of purpose-in-life, quality of life, spiritual well-being, self-efficacy, optimism, distress, hopelessness, anxiety, depression and wish to hasten death. This review provides an explanatory model of the contextual factors and mechanisms that may be involved in promoting meaning in life. These approaches could provide useful tools for relieving existential suffering at the end of life.

  19. Understanding the impact of deep brain stimulation on ambulatory activity in advanced Parkinson's disease.

    PubMed

    Rochester, Lynn; Chastin, Sebastien Francois Martin; Lord, Sue; Baker, Katherine; Burn, David John

    2012-06-01

    Whilst deep brain stimulation of the subthalamic nucleus (DBS-STN) improves the motor symptoms of Parkinson's disease (PD), its effect on daily activity is unknown. We aimed to quantify changes in ambulatory activity following DBS-STN in advanced PD using novel accelerometry based measures that describe changes to the volume and pattern of walking. Seventeen participants with advanced PD were measured over a 7-day period using an activPAL (™) activity monitor. Data were collected 6 weeks before and 6 months after surgery and included measures that describe the volume and pattern of ambulatory activity (number of steps per day, accumulation, diversity and variability of walking time), alongside standard measures for disease severity, freezing of gait, gait speed, and extended activities of daily living. Activity outcomes were compared pre- and 6 months post-surgery using linear mixed models and correlated with standard outcomes. The results of this study are despite significant improvements in motor symptoms after surgery, the volume of ambulatory activity (total number of steps per day) did not change (P = 0.468). However, significant increases in length and variability of walking bouts emerged, suggesting improvements in diversity and flexibility of walking patterns. Motor severity and extended activities of daily living scores were significantly correlated with walking bout variability but not with volume of walking. Thus, the conclusions are reduction in motor symptom severity after DBS-STN translated into selective improvements in daily activity. Novel measures derived from accelerometry provide a discrete measure of performance and allow closer interpretation of the impact of DBS-STN on real-world activity.

  20. Kiss of the Mutant Mouse: How Genetically Altered Mice Advanced Our Understanding of Kisspeptin's Role in Reproductive Physiology

    PubMed Central

    Elias, Carol F.

    2012-01-01

    The kisspeptin system has emerged as one of the most important circuits within the central network governing reproduction. Although kisspeptin physiology has been examined in many species, much of our understanding of this system has come from mice. Recently, the study of several innovative strains of genetically engineered mouse models has revealed intriguing and unexpected insights into the functions of kisspeptin signaling in the hypothalamus. Here, we review the advancements in our knowledge of the central kisspeptin system through the use of mutant mice. PMID:23011921

  1. Institute for Theoretical Physics

    SciTech Connect

    Giddings, S.B.; Ooguri, H.; Peet, A.W.; Schwarz, J.H.

    1998-06-01

    String theory is the only serious candidate for a unified description of all known fundamental particles and interactions, including gravity, in a single theoretical framework. Over the past two years, activity in this subject has grown rapidly, thanks to dramatic advances in understanding the dynamics of supersymmetric field theories and string theories. The cornerstone of these new developments is the discovery of duality which relates apparently different string theories and transforms difficult strongly coupled problems of one theory into weakly coupled problems of another theory.

  2. Advances In Understanding Global Water Cycle With Advent of GPM Mission

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.

    2002-01-01

    During the coming decade, the internationally organized Global Precipitation Measurement (GPM) Mission will take an important step in creating a global precipitation observing system from space based on an international fleet of satellites operated as a constellation. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams beginning with very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and then on to blends of the former datastreams with additional lower-caliber PMW-based and IR-based rain retrievals. Within the context of the now emerging global water & energy cycle (GWEC) programs of a number of research agencies throughout the world, GPM serves as a centerpiece space mission for improving our understanding of the Earth's water cycle from a global measurement perspective and on down to regional scales and below. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in climate, e.g., climate warming. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination. This paper first presents an overview of the GPM Mission and how its overriding scientific objectives for climate, weather, and hydrology flow from the anticipated improvements that are being planned for the constellation-based measuring system. Next, the paper shows how the GPM observations can be used within the framework of the oceanic and continental water budget equations to determine whether a given perturbation in precipitation is indicative of an actual rate change in the water cycle, consistent with required responses in water storage and/or water flux transport processes, or whether it is simply part of the natural

  3. Advances in Understanding Global Water Cycle with Advent of Global Precipitation Measurement (GPM) Mission

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.; Starr, David (Technical Monitor)

    2002-01-01

    Within this decade the internationally organized Global Precipitation Measurement (GPM) Mission will take an important step in creating a global precipitation observing system from space. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams beginning with very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and then on to blends of the former datastreams with additional lower-caliber PMW-based and IR-based rain retrievals. Within the context of the now emerging global water & energy cycle (GWEC) programs of a number of research agencies throughout the world, GPM serves as a centerpiece space mission for improving our understanding of the global water cycle from a global measurement perspective. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in climate, e.g., climate warming. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination. This paper presents an overview of the GPM Mission and how its observations can be used within the framework of the oceanic and continental water budget equations to determine whether a given perturbation in precipitation is indicative of an actual rate change in the global water cycle, consistent with required responses in water storage and/or water flux transport processes, or whether it is the natural variability of a fixed rate cycle.

  4. Advances in Understanding Global Water Cycle with Advent of Global Precipitation Measurement (GPM) Mission

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.; Starr, David (Technical Monitor)

    2002-01-01

    Within this decade the internationally organized Global Precipitation Measurement (GPM) Mission will take an important step in creating a global precipitation observing system from space. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams beginning with very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and then on to blends of the former datastreams with additional lower-caliber PMW-based and IR-based rain retrievals. Within the context of the now emerging global water & energy cycle (GWEC) programs of a number of research agencies throughout the world, GPM serves as a centerpiece space mission for improving our understanding of the global water cycle from a global measurement perspective. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in climate, e.g., climate warming. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination. This paper presents an overview of the GPM Mission and how its observations can be used within the framework of the oceanic and continental water budget equations to determine whether a given perturbation in precipitation is indicative of an actual rate change in the global water cycle, consistent with required responses in water storage and/or water flux transport processes, or whether it is the natural variability of a fixed rate cycle.

  5. Advances In Understanding Global Water Cycle With Advent of GPM Mission

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.

    2002-01-01

    During the coming decade, the internationally organized Global Precipitation Measurement (GPM) Mission will take an important step in creating a global precipitation observing system from space based on an international fleet of satellites operated as a constellation. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams beginning with very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and then on to blends of the former datastreams with additional lower-caliber PMW-based and IR-based rain retrievals. Within the context of the now emerging global water & energy cycle (GWEC) programs of a number of research agencies throughout the world, GPM serves as a centerpiece space mission for improving our understanding of the Earth's water cycle from a global measurement perspective and on down to regional scales and below. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in climate, e.g., climate warming. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination. This paper first presents an overview of the GPM Mission and how its overriding scientific objectives for climate, weather, and hydrology flow from the anticipated improvements that are being planned for the constellation-based measuring system. Next, the paper shows how the GPM observations can be used within the framework of the oceanic and continental water budget equations to determine whether a given perturbation in precipitation is indicative of an actual rate change in the water cycle, consistent with required responses in water storage and/or water flux transport processes, or whether it is simply part of the natural

  6. Pediatric Cerebellar Tumors: Emerging Imaging Techniques and Advances in Understanding of Genetic Features.

    PubMed

    Choudhri, Asim F; Siddiqui, Adeel; Klimo, Paul

    2016-08-01

    Cerebellar tumors are the most common group of solid tumors in children. MR imaging provides an important role in characterization of these lesions, surgical planning, and postsurgical surveillance. Preoperative imaging can help predict the histologic subtype of tumors, which can provide guidance for surgical planning. Beyond histology, pediatric brain tumors are undergoing new classification schemes based on genetic features. Intraoperative MR imaging has emerged as an important tool in the surgical management of pediatric brain tumors. Effective understanding of the imaging features of pediatric cerebellar tumors can benefit communication with neurosurgeons and neuro-oncologists and can improve patient management.

  7. Advances in the understanding of the Fanconi anemia tumor suppressor pathway.

    PubMed

    Pickering, Anna; Zhang, Jun; Panneerselvam, Jayabal; Fei, Peiwen

    2013-12-01

    Extremely high cancer incidence in Fanconi anemia (FA) patients has long suggested that the FA signaling pathway is a tumor suppressor pathway. Indeed, our recent findings, for the first time, indicate that the FA pathway plays a significant role in suppressing the development of non-FA human cancer. Also our studies on FA group D2 protein (FANCD2) have, among the first, documented the crosstalks between the FA and Rad6/Rad18 (HHR6) pathways upon DNA damage. In this review, we will discuss how our studies enhance the understanding of the FA tumor suppressor pathway.

  8. The impact of recent advances in genetics in understanding disease mechanisms underlying the long QT syndromes.

    PubMed

    Harmer, Stephen C; Tinker, Andrew

    2016-07-01

    Long QT syndrome refers to a characteristic abnormality of the electrocardiogram and it is associated with a form of ventricular tachycardia known as torsade-de-pointes and sudden arrhythmic death. It can occur as part of a hereditary syndrome or can be acquired usually because of drug administration. Here we review recent genetic, molecular and cellular discoveries and outline how they have furthered our understanding of this disease. Specifically we focus on compound mutations, genome wide association studies of QT interval, modifier genes and the therapeutic implications of this recent work.

  9. An advanced understanding of the specific effects of xylan and surface lignin contents on enzymatic hydrolysis of lignocellulosic biomass

    SciTech Connect

    Ju, Xiaohui; Engelhard, Mark H.; Zhang, Xiao

    2013-01-17

    A deep understanding of biomass recalcitrance has been hampered by the intricate and heterogeneous nature of pretreated biomass substrates obtained from random deconstruction methods. In this study, we established a unique methodology based on chemical pulping principles to create "reference substrates" with intact cellulose fibers and controlled morphological and chemical properties that enable us to investigate the individual effect of xylan, bulk, and surface lignin content on enzymatic hydrolysis. We also developed and demonstrated an X-ray photoelectron spectroscopy (XPS) technique for quantifying surface lignin content on biomass substrates. The results from this study show that, apart from its hindrance effect, xylan can facilitate cellulose fibril swelling and thus create more accessible surface area, which improves enzyme and substrate interactions. Surface lignin has a significant impact on enzyme adsorption kinetics and hydrolysis rate. Advanced understanding of xylan, bulk, and surface lignin effects provides critical information for an effective biomass conversion process.

  10. Advances in the understanding of the pathogenesis and epidemiology of herpes zoster

    PubMed Central

    Gershon, Anne A.; Gershon, Michael D.; Breuer, Judith; Levin, Myron J.; Oaklander, Anne Louise; Griffiths, Paul D.

    2017-01-01

    SUMMARY The primary varicella zoster virus (VZV) infection results in chickenpox (varicella), which is transmitted via the airborne route. VZV is highly infectious, but in the USA the incidence of varicella has been reduced by 76–87% as a result of the varicella vaccine. The virus establishes latency in the dorsal root ganglia during varicella and, when reactivated, travels along the sensory nerve axons to cause shingles (herpes zoster [HZ]). There are over 1 million cases of HZ in the USA each year, with an estimated lifetime attack rate of 30%. The incidence of HZ, which causes significant morbidity, increases with age and reaches approximately 10 cases per 1,000 patient-years by age 80. Cell-mediated immunity (CMI) is known to decline with age as part of immunosenescence, and decreased CMI is associated with reactivation of VZV. This article provides an overview of our emerging understanding of the epidemiology and pathogenesis of varicella and HZ, in addition to exploring the current theories on latency and reactivation. Understanding the risk factors for developing HZ and the complications associated with infection, particularly in older people, is important for prompt diagnosis and management of HZ in primary care, and they are therefore also reviewed. PMID:20510263

  11. Advances in the understanding of delayed cerebral ischaemia after aneurysmal subarachnoid haemorrhage

    PubMed Central

    Flynn, Liam; Andrews, Peter

    2015-01-01

    Delayed cerebral ischaemia has been described as the single most important cause of morbidity and mortality in patients who survive the initial aneurysmal subarachnoid haemorrhage. Our understanding of the pathophysiology of delayed cerebral ischaemia is meagre at best and the calcium channel blocker nimodipine remains the only intervention to consistently improve functional outcome after aneurysmal subarachnoid haemorrhage. There is substantial evidence to support cerebral vessel narrowing as a causative factor in delayed cerebral ischaemia, but contemporary research demonstrating improvements in vessel narrowing has failed to show improved functional outcomes. This has encouraged researchers to investigate other potential causes of delayed cerebral ischaemia, such as early brain injury, microthrombosis, and cortical spreading depolarisation. Adherence to a common definition of delayed cerebral ischaemia is needed in order to allow easier assessment of studies using multiple different terms. Furthermore, improved recognition of delayed cerebral ischaemia would not only allow for faster treatment but also better assessment of interventions. Finally, understanding nimodipine’s mechanism of action may allow us to develop similar agents with improved efficacy. PMID:26937276

  12. The Climate Variability & Predictability (CVP) Program at NOAA - Recent Program Advancements in Understanding AMOC

    NASA Astrophysics Data System (ADS)

    Lucas, S. E.

    2016-12-01

    The Climate Variability & Predictability (CVP) Program supports research aimed at providing process-level understanding of the climate system through observation, modeling, analysis, and field studies. This vital knowledge is needed to improve climate models and predictions so that scientists can better anticipate the impacts of future climate variability and change. To achieve its mission, the CVP Program supports research carried out at NOAA and other federal laboratories, NOAA Cooperative Institutes, and academic institutions. The Program also coordinates its sponsored projects with major national and international scientific bodies including the World Climate Research Programme (WCRP), the International and U.S. Climate Variability and Predictability (CLIVAR/US CLIVAR) Program, and the U.S. Global Change Research Program (USGCRP). The CVP program sits within NOAA's Climate Program Office (http://cpo.noaa.gov/CVP). This poster will present the recently funded CVP projects on improving the understanding Atlantic Meridional Overturning Circulation (AMOC), its impact on decadal predictability, and its relationship with the overall climate system.

  13. Recent advances in understanding of meiosis initiation and the apomictic pathway in plants.

    PubMed

    Wang, Chung-Ju R; Tseng, Ching-Chih

    2014-01-01

    Meiosis, a specialized cell division to produce haploid cells, marks the transition from a sporophytic to a gametophytic generation in the life cycle of plants. In angiosperms, meiosis takes place in sporogenous cells that develop de novo from somatic cells in anthers or ovules. A successful transition from the mitotic cycle to the meiotic program in sporogenous cells is crucial for sexual reproduction. By contrast, when meiosis is bypassed or a mitosis-like division occurs to produce unreduced cells, followed by the development of an embryo sac, clonal seeds can be produced by apomixis, an asexual reproduction pathway found in 400 species of flowering plants. An understanding of the regulation of entry into meiosis and molecular mechanisms of apomictic pathway will provide vital insight into reproduction for plant breeding. Recent findings suggest that AM1/SWI1 may be the key gene for entry into meiosis, and increasing evidence has shown that the apomictic pathway is epigenetically controlled. However, the mechanism for the initiation of meiosis during sexual reproduction or for its omission in the apomictic pathway still remains largely unknown. Here we review the current understanding of meiosis initiation and the apomictic pathway and raised several questions that are awaiting further investigation.

  14. Recent advances in understanding endometrial receptivity: molecular basis and clinical applications.

    PubMed

    von Grothusen, Carolina; Lalitkumar, Sujata; Boggavarapu, Nageswara Rao; Gemzell-Danielsson, Kristina; Lalitkumar, Parameswaran G

    2014-08-01

    Advancement in the field of ART has lead to the possibility of achieving good quality embryos. However, the success rate in ART needs further improvement. This is largely dependent on identifying the receptive endometrium for the successful implantation of embryos as well as modulating the endometrium to the receptive stage. In the last half-a-decade, focus has been shifting toward identifying the receptive endometrium. Here, we summarize different tools explored to identify receptive endometrium from the literature, mainly focusing on the past decade, with the help of PubMed. The quest to identify endometrial receptivity markers has lead to the exploration of morphological features at micro and macro scale levels. A large number of studies at molecular levels have focused on genomic, proteomic and lipidomic targets. Recent development of endometrial receptivity array is a promising diagnostic instrument. However, a noninvasive possibility for the diagnosis of endometrial receptivity would be an ideal tool, which could be used in the clinic to improve the success rate of ART. Improved knowledge on endometrial receptivity will not only help to improve the diagnosis and treatment of infertility but will also give possibilities to develop new contraceptive methods targeting the endometrium.

  15. Understanding the operational parameters affecting NDMA formation at Advanced Water Treatment Plants.

    PubMed

    Farré, Maria José; Döderer, Katrin; Hearn, Laurence; Poussade, Yvan; Keller, Jurg; Gernjak, Wolfgang

    2011-01-30

    N-nitrosodimethylamine (NDMA) can be formed when secondary effluents are disinfected by chloramines. By means of bench scale experiments this paper investigates operational parameters than can help Advanced Water Treatment Plants (AWTPs) to reduce the formation of NDMA during the production of high quality recycled water. The formation of NDMA was monitored during a contact time of 24h using dimethylamine as NDMA model precursor and secondary effluent from wastewater treatment plants. The three chloramine disinfection strategies tested were pre-formed and in-line formed monochloramine, and pre-formed dichloramine. Although the latter is not employed on purpose in full-scale applications, it has been suggested as the main contributing chemical generating NDMA during chloramination. After 24h, the NDMA formation decreased in both matrices tested in the order: pre-formed dichloramine>in-line formed monochloramine≫pre-formed monochloramine. The most important parameter to consider for the inhibition of NDMA formation was the length of contact time between disinfectant and wastewater. Formation of NDMA was initially inhibited for up to 6h with concentrations consistently <10 ng/L during these early stages of disinfection, regardless of the disinfection strategy. The reduction of the contact time was implemented in Bundamba AWTP (Queensland, Australia), where NDMA concentrations were reduced by a factor of 20 by optimizing the disinfection strategy. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Recent Advances in Improvement of Forecast Skill and Understanding Climate Processes Using AIRS Version-5 Products

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Molnar, Gyula; Iredell, Lena; Rosenberg, Robert

    2012-01-01

    AIRS/AMSU is the state of the art infrared and microwave atmospheric sounding system flying aboard EOS Aqua. These observations, covering the period September 2002 until the present, have been analyzed using the AIRS Science Team Version-5 retrieval algorithm. AIRS is a high spectral resolution infrared grating spectrometer with spect,ral coverage from 650 per centimeter extending to 2660 per centimeter, with low noise and a spectral resolving power of 2400. A brief overview of the AIRS Version-5 retrieval procedure will be presented, including the AIRS channels used in different steps in the retrieval process. Many researchers have used these products to make significant advances in both climate and weather applications. Recent significant results of these experiments will be presented, including results showing that 1) assimilation of AIRS Quality Controlled temperature profiles into a General Circulation Model (GCM) significantly improves the ability to predict storm tracks of intense precipitation events; and 2) anomaly time-series of Outgoing Longwave Radiation (OLR) computed using AIRS sounding products closely match those determined from the CERES instrument, and furthermore explain that the phenomenon that global and especially tropical mean OLR have been decreasing since September 2002 is a result of El Nino/La Nina oscillations during this period.

  17. Recent Advances in Understanding and Mitigating Adipogenic and Metabolic Effects of Antipsychotic Drugs

    PubMed Central

    Gohlke, Julia M.; Dhurandhar, Emily J.; Correll, Christoph U.; Morrato, Elaine H.; Newcomer, John W.; Remington, Gary; Nasrallah, Henry A.; Crystal, Stephen; Nicol, Ginger; Allison, David B.

    2012-01-01

    Although offering many benefits for several psychiatric disorders, antipsychotic drugs (APDs) as a class have a major liability in their tendency to promote adiposity, obesity, and metabolic dysregulation in an already metabolically vulnerable population. The past decade has witnessed substantial research aimed at investigating the mechanisms of these adverse effects and mitigating them. On July 11 and 12, 2011, with support from 2 NIH institutes, leading experts convened to discuss current research findings and to consider future research strategies. Five areas where significant advances are being made emerged from the conference: (1) methodological issues in the study of APD effects; (2) unique characteristics and needs of pediatric patients; (3) genetic components underlying susceptibility to APD-induced metabolic effects; (4) APD effects on weight gain and adiposity in relation to their acute effects on glucose regulation and diabetes risk; and (5) the utility of behavioral, dietary, and pharmacological interventions in mitigating APD-induced metabolic side effects. This paper summarizes the major conclusions and important supporting data from the meeting. PMID:22754543

  18. Recent advances in understanding the genetic architecture of type 2 diabetes

    PubMed Central

    Mohlke, Karen L.; Boehnke, Michael

    2015-01-01

    Genome-wide association (GWAS) and sequencing studies are providing new insights into the genetic basis of type 2 diabetes (T2D) and the inter-individual variation in glycemic traits, including levels of glucose, insulin, proinsulin and hemoglobin A1c (HbA1c). At the end of 2011, established loci (P < 5 × 10−8) totaled 55 for T2D and 32 for glycemic traits. Since then, most new loci have been detected by analyzing common [minor allele frequency (MAF)>0.05] variants in increasingly large sample sizes from populations around the world, and in trans-ancestry studies that successfully combine data from diverse populations. Most recently, advances in sequencing have led to the discovery of four loci for T2D or glycemic traits based on low-frequency (0.005 < MAF ≤ 0.05) variants, and additional low-frequency, potentially functional variants have been identified at GWAS loci. Established published loci now total ∼88 for T2D and 83 for one or more glycemic traits, and many additional loci likely remain to be discovered. Future studies will build on these successes by identifying additional loci and by determining the pathogenic effects of the underlying variants and genes. PMID:26160912

  19. Advances in IL-21 biology - enhancing our understanding of human disease.

    PubMed

    Tangye, Stuart G

    2015-06-01

    Cytokines play critical roles in regulating the development and function of immune cells. Cytokines function by binding specific multimeric receptor complexes and activating intracellular signaling pathways that often involve JAKs and STATs. In addition to contributing to immunity, when production of cytokines is perturbed, they can contribute to disease. IL-21 is a pleiotropic cytokine produced predominantly by CD4(+) T cells and NKT cells. Gene-targeting studies in mice and in vitro analyses of human and murine lymphocytes have revealed central roles of IL-21 in regulating effector functions of T cells, NK cells and B cells. However, recent discoveries of loss-of function mutations in IL21 or IL21R in humans have unveiled unexpected roles for IL-21 in immune regulation. This review will focus on recent advances in IL-21 biology that have highlighted its critical role in normal immunity and how dysregulated IL-21 production can lead to immunodeficiency and autoimmune conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Advances in Understanding Sorption and Transport Processes Affecting the Fate of Environmental Pollutants in the Subsurface

    NASA Astrophysics Data System (ADS)

    Karapanagioti, H. K.; Werner, D.; Werth, C.

    2012-04-01

    The results of a call for a special issue that is now in press by the Journal of Contaminant Hydrology will be presented. This special issue is edited by the authors and is entitled "Sorption and Transport Processes Affecting the Fate of Environmental Pollutants in the Subsurface". A short abstract of each paper will be presented along with the most interesting results. Nine papers were accepted. Pollutants studied include: biocolloids, metals (arsenic, chromium, nickel), organic compounds such as hydrocarbons, chlorinated hydrocarbons, micropollutants (PAHs, PCBs), pesticides (glyphosate, 2,4-D). Findings presented in the papers include a modified batch reactor system to study equilibrium-reactive transport problems of metals. Column studies along with theoretical approximations evaluate the combined effects of grain size and pore water velocity on the transport in water saturated porous media of three biocolloids. A polluted sediment remediation method is evaluated considering site-specific conditions through monitoring results and modelling. A field study points to glogging and also sorption as mechanisms affecting the effectiveness of sub-surface flow constructed wetlands. A new isotherm model combining modified traditionally used isotherms is proposed that can be used to simulate pH-dependent metal adsorption. Linear free energy relationships (LFERs) demonstrate ability to predict slight isotope shifts into the groundwater due to sorption. Possible modifications that improve the reliability of kinetic models and parameter values during the evaluation of experiments that assess the sorption of pesticides on soils are tested. Challenges in selecting groundwater pollutant fate and transport models that account for the effect of grain-scale sorption rate limitations are evaluated based on experimental results and are discussed based on the Damköhler number. Finally, a thorough review paper presents the impact of mineral micropores on the transport and fate of

  1. Recent Advances in Understanding the Control of Secretory Proteins by the Unfolded Protein Response in Plants

    PubMed Central

    Hayashi, Shimpei; Wakasa, Yuhya; Takaiwa, Fumio

    2013-01-01

    The membrane transport system is built on the proper functioning of the endoplasmic reticulum (ER). The accumulation of unfolded proteins in the ER lumen (ER stress) disrupts ER homeostasis and disturbs the transport system. In response to ER stress, eukaryotic cells activate intracellular signaling (named the unfolded protein response, UPR), which contributes to the quality control of secretory proteins. On the other hand, the deleterious effects of UPR on plant health and growth characteristics have frequently been overlooked, due to limited information on this mechanism. However, recent studies have shed light on the molecular mechanism of plant UPR, and a number of its unique characteristics have been elucidated. This study briefly reviews the progress of understanding what is happening in plants under ER stress conditions. PMID:23629671

  2. From endocrine disruptors to nanomaterials: advancing our understanding of environmental health to protect public health.

    PubMed

    Birnbaum, Linda S; Jung, Paul

    2011-05-01

    Environmental health science is the study of the impact of the environment on human health. This paper introduces basic topics in environmental health, including clean air, clean water, and healthful food, as well as a range of current issues and controversies in environmental health. Conceptual shifts in modern toxicology have changed the field. There is a new understanding of the effects of exposure to chemicals at low doses, and in combination, and the impact on human growth and development. Other emerging topics include the role of epigenetics, or changes in genes and gene expression that can be brought about by chemical exposure; environmental justice; and potential effects of engineered nanomaterials and climate change. We review the important implications for public health policy and recommend a broad environmental health research strategy aimed at protecting and improving human health.

  3. Recent advances in understanding the role of cellulose accessibility in enzymatic hydrolysis of lignocellulosic substrates.

    PubMed

    Meng, Xianzhi; Ragauskas, Arthur Jonas

    2014-06-01

    Cellulose accessibility has been proposed as a key factor in the efficient bio-conversion of lignocellulosic biomass to fermentable sugars. Factors affecting cellulose accessibility can be divided into direct factors that refer to accessible surface area of cellulose, and indirect factors referring to chemical composition such as lignin/hemicellulose content, and biomass structure-relevant factors (i.e. particle size, porosity). An overview of the current pretreatment technologies special focus on the major mode of action to increase cellulose accessibility as well as multiple techniques that could be used to assess the cellulose accessibility are presented in this review. The appropriate determination of cellulose accessibility before and after pretreatment can assist to understand the effectiveness of a particular pretreatment in overcoming lignocellulosic recalcitrance to improve substrate enzymatic digestibility.

  4. Recent advances in understanding the enzymatic reactions of [4+2] cycloaddition and spiroketalization.

    PubMed

    Zheng, Qingfei; Tian, Zhenhua; Liu, Wen

    2016-04-01

    Diels-Alder-like [4+2] cycloaddition and ketalization of dihydroxy ketones are cyclization reactions with different mechanisms that produce characteristic cyclohexene and spiroketal units, respectively. Here, we review newly identified, naturally occurring '[4+2] cycloadditionases' and 'spiroketalases' and reveal several similarities between the two types of enzymes. During catalysis, these enzymes control product stereochemistry or/and enhance the transformation rate. They exhibit convergent evolution of [4+2] cycloaddition or spiroketalization activity, which is likely dependent on interactions of variable protein folds with specialized chemical structures. An understanding of these similarities is expected to allow for establishment of the underlying principles for the application and catalyst design of associated enzymatic reactions in organic chemistry and synthetic biology.

  5. Recent advances in understanding neuropathic pain: glia, sex differences, and epigenetics

    PubMed Central

    Machelska, Halina; Celik, Melih Ö.

    2016-01-01

    Neuropathic pain results from diseases or trauma affecting the nervous system. This pain can be devastating and is poorly controlled. The pathophysiology is complex, and it is essential to understand the underlying mechanisms in order to identify the relevant targets for therapeutic intervention. In this article, we focus on the recent research investigating neuro-immune communication and epigenetic processes, which gain particular attention in the context of neuropathic pain. Specifically, we analyze the role of glial cells, including microglia, astrocytes, and oligodendrocytes, in the modulation of the central nervous system inflammation triggered by neuropathy. Considering epigenetics, we address DNA methylation, histone modifications, and the non-coding RNAs in the regulation of ion channels, G-protein-coupled receptors, and transmitters following neuronal damage. The goal was not only to highlight the emerging concepts but also to discuss controversies, methodological complications, and intriguing opinions. PMID:28105313

  6. Advances towards understanding and engineering direct interspecies electron transfer in anaerobic digestion.

    PubMed

    Barua, Sajib; Dhar, Bipro Ranjan

    2017-11-01

    Direct interspecies electron transfer (DIET) is a recently discovered microbial syntrophy where cell-to-cell electron transfer occurs between syntrophic microbial species. DIET between bacteria and methanogenic archaea in anaerobic digestion can accelerate the syntrophic conversion of various reduced organic compounds to methane. DIET-based syntrophy can naturally occur in some anaerobic digester via conductive pili, however, can be engineered via the addition of various non-biological conductive materials. In recent years, research into understanding and engineering DIET-based syntrophy has emerged with the aim of improving methanogenesis kinetics in anaerobic digestion. This article presents a state-of-art review focusing on the fundamental mechanisms, key microbial players, the role of electrical conductivity, the effectiveness of various conductive additives, the significance of substrate characteristics and organic loading rates in promoting DIET in anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Advances in understanding the pathogenesis of CNS acute lymphoblastic leukaemia and potential for therapy.

    PubMed

    Frishman-Levy, Liron; Izraeli, Shai

    2017-01-01

    Central nervous system acute lymphoblastic leukaemia (CNS-ALL) is a major clinical problem. CNS-directed 'prophylactic' chemo- or radio - therapy is associated with significant early and long-term toxicity. Moreover, greater than a third of the relapses occur in the CNS. To design specific, more effective and less toxic therapy and for personalized precise adjustment of prophylactic therapy there is a need for better understanding of the biology of this disease. Specifically, the precise neurotropic mechanisms of ALL are currently unclear, as is the pathogenesis of CNS relapse. Here we review and contrast the recent findings with earlier studies of pathogenesis of CNS leukaemia. We also describe the challenges in research of this devastating complication of ALL. © 2016 John Wiley & Sons Ltd.

  8. Recent advances in understanding carotenoid-derived signaling molecules in regulating plant growth and development.

    PubMed

    Tian, Li

    2015-01-01

    Carotenoids (C40) are synthesized in plastids and perform numerous important functions in these organelles. In addition, carotenoids can be processed into smaller signaling molecules that regulate various phases of the plant's life cycle. Besides the relatively well-studied phytohormones abscisic acid (ABA) and strigolactones (SLs), additional carotenoid-derived signaling molecules have been discovered and shown to regulate plant growth and development. As a few excellent reviews summarized recent research on ABA and SLs, this mini review will focus on progress made on identification and characterization of the emerging carotenoid-derived signals. Overall, a better understanding of carotenoid-derived signaling molecules has immediate applications in improving plant biomass production which in turn will have far reaching impacts on providing food, feed, and fuel for the growing world population.

  9. Advancing our understanding of infant bronchiolitis through phenotyping and endotyping: Clinical and molecular approaches

    PubMed Central

    Hasegawa, Kohei; Dumas, Orianne; Hartert, Tina V.; Camargo, Carlos A.

    2016-01-01

    Introduction Bronchiolitis is a major public health problem worldwide. However, no effective treatment strategies are available, other than supportive care. Areas Covered Although bronchiolitis has been considered a single disease diagnosed based on clinical characteristics, emerging evidence supports both clinical and pathobiological heterogeneity. The characterization of this heterogeneity supports the concept that bronchiolitis consists of multiple phenotypes or consistent grouping of characteristics. Expert Commentary Using unbiased statistical approaches, multidimentional clinical characteristics will derive bronchiolitis phenotypes. Furthermore, molecular and systems biology approaches will, by linking pathobiology to phenotype, identify endotypes. Large cohort studies of bronchiolitis with comprehensive clinical characterization and system-wide profiling of the “-omics” data (e.g., host genome, transcriptome, epigenome, viral genome, microbiome, metabolome) should enhance our ability to molecularly understand these phenotypes and lead to more targeted and personalized approaches to bronchiolitis treatment. PMID:27192374

  10. Advancing our understanding of infant bronchiolitis through phenotyping and endotyping: clinical and molecular approaches.

    PubMed

    Hasegawa, Kohei; Dumas, Orianne; Hartert, Tina V; Camargo, Carlos A

    2016-08-01

    Bronchiolitis is a major public health problem worldwide. However, no effective treatment strategies are available, other than supportive care. Although bronchiolitis has been considered a single disease diagnosed based on clinical characteristics, emerging evidence supports both clinical and pathobiological heterogeneity. The characterization of this heterogeneity supports the concept that bronchiolitis consists of multiple phenotypes or consistent grouping of characteristics. Expert commentary: Using unbiased statistical approaches, multidimentional clinical characteristics will derive bronchiolitis phenotypes. Furthermore, molecular and systems biology approaches will, by linking pathobiology to phenotype, identify endotypes. Large cohort studies of bronchiolitis with comprehensive clinical characterization and system-wide profiling of the '-omics' data (e.g., host genome, transcriptome, epigenome, viral genome, microbiome, metabolome) should enhance our ability to molecularly understand these phenotypes and lead to more targeted and personalized approaches to bronchiolitis treatment.

  11. Advances in Understanding of Penile Carcinogenesis: The Search for Actionable Targets.

    PubMed

    Chipollini, Juan; Chaing, Sharon; Azizi, Mounsif; Kidd, Laura C; Kim, Patricia; Spiess, Philippe E

    2017-08-16

    Penile cancer (PeCa) is a rare malignancy with potentially devastating effects. Squamous cell carcinoma is the most common variant with distinct precancerous lesions before development into invasive disease. Involvement of the inguinal lymph nodes is the most important prognostic factor in PeCa, and once disease is present outside the groin, prognosis is poor. Metastatic PeCa is challenging to treat and often requires multidisciplinary approaches in management. Due to its rarity, molecular understanding of the disease continues to be limited with most studies based on small, single center series. Thus far, it appears PeCa has diverse mechanisms of carcinogenesis affecting similar molecular pathways. In this review, we evaluate the current landscape of the molecular carcinogenesis of PeCa and explore ongoing research on potential actionable targets of therapy. The emergence of anti-epidermal growth factor receptor (EGFR) and other immunotherapeutic strategies may improve outcomes for PeCa patients.

  12. Advances in the understanding of mitochondrial DNA as a pathogenic factor in inflammatory diseases

    PubMed Central

    Boyapati, Ray K.; Tamborska, Arina; Dorward, David A.; Ho, Gwo-Tzer

    2017-01-01

    Mitochondrial DNA (mtDNA) has many similarities with bacterial DNA because of their shared common ancestry. Increasing evidence demonstrates mtDNA to be a potent danger signal that is recognised by the innate immune system and can directly modulate the inflammatory response. In humans, elevated circulating mtDNA is found in conditions with significant tissue injury such as trauma and sepsis and increasingly in chronic organ-specific and systemic illnesses such as steatohepatitis and systemic lupus erythematosus. In this review, we examine our current understanding of mtDNA-mediated inflammation and how the mechanisms regulating mitochondrial homeostasis and mtDNA release represent exciting and previously under-recognised important factors in many human inflammatory diseases, offering many new translational opportunities. PMID:28299196

  13. Combining natural and man-made DNA tracers to advance understanding of hydrologic flow pathway evolution

    NASA Astrophysics Data System (ADS)

    Dahlke, H. E.; Walter, M. T.; Lyon, S. W.; Rosqvist, G. N.

    2014-12-01

    Identifying and characterizing the sources, pathways and residence times of water and associated constituents is critical to developing improved understanding of watershed-stream connections and hydrological/ecological/biogeochemical models. To date the most robust information is obtained from integrated studies that combine natural tracers (e.g. isotopes, geochemical tracers) with controlled chemical tracer (e.g., bromide, dyes) or colloidal tracer (e.g., carboxilated microspheres, tagged clay particles, microorganisms) applications. In the presented study we explore how understanding of sources and flow pathways of water derived from natural tracer studies can be improved and expanded in space and time by simultaneously introducing man-made, synthetic DNA-based microtracers. The microtracer used were composed of polylactic acid (PLA) microspheres into which short strands of synthetic DNA and paramagnetic iron oxide nanoparticles are incorporated. Tracer experiments using both natural tracers and the DNA-based microtracers were conducted in the sub-arctic, glacierized Tarfala (21.7 km2) catchment in northern Sweden. Isotopic hydrograph separations revealed that even though storm runoff was dominated by pre-event water the event water (i.e. rainfall) contributions to streamflow increased throughout the summer season as glacial snow cover decreased. This suggests that glaciers are a major source of the rainwater fraction in streamflow. Simultaneous injections of ten unique DNA-based microtracers confirmed this hypothesis and revealed that the transit time of water traveling from the glacier surface to the stream decreased fourfold over the summer season leading to instantaneous rainwater contributions during storm events. These results highlight that integrating simultaneous tracer injections (injecting tracers at multiple places at one time) with traditional tracer methods (sampling multiple times at one place) rather than using either approach in isolation can

  14. Advances in Our Understanding of Oxylipins Derived from Dietary PUFAs12

    PubMed Central

    Gabbs, Melissa; Leng, Shan; Devassy, Jessay G; Monirujjaman, Md; Aukema, Harold M

    2015-01-01

    Oxylipins formed from polyunsaturated fatty acids (PUFAs) are the main mediators of PUFA effects in the body. They are formed via cyclooxygenase, lipoxygenase, and cytochrome P450 pathways, resulting in the formation of prostaglandins, thromboxanes, mono-, di-, and tri-hydroxy fatty acids (FAs), epoxy FAs, lipoxins, eoxins, hepoxilins, resolvins, protectins (also called neuroprotectins in the brain), and maresins. In addition to the well-known eicosanoids derived from arachidonic acid, recent developments in lipidomic methodologies have raised awareness of and interest in the large number of oxylipins formed from other PUFAs, including those from the essential FAs and the longer-chain n–3 (ω-3) PUFAs. Oxylipins have essential roles in normal physiology and function, but can also have detrimental effects. Compared with the oxylipins derived from n–3 PUFAs, oxylipins from n–6 PUFAs generally have greater activity and more inflammatory, vasoconstrictory, and proliferative effects, although there are notable exceptions. Because PUFA composition does not necessarily reflect oxylipin composition, comprehensive analysis of the oxylipin profile is necessary to understand the overall physiologic effects of PUFAs mediated through their oxylipins. These analyses should include oxylipins derived from linoleic and α-linolenic acids, because these largely unexplored bioactive oxylipins constitute more than one-half of oxylipins present in tissues. Because collated information on oxylipins formed from different PUFAs is currently unavailable, this review provides a detailed compilation of the main oxylipins formed from PUFAs and describes their functions. Much remains to be elucidated in this emerging field, including the discovery of more oxylipins, and the understanding of the differing biological potencies, kinetics, and isomer-specific activities of these novel PUFA metabolites. PMID:26374175

  15. Understanding Advance Care Planning as a Process of Health Behavior Change

    PubMed Central

    Fried, Terri R.; Bullock, Karen; Iannone, Lynne; O'Leary, John R.

    2009-01-01

    Objectives To explore whether models of health behavior change can help to inform interventions for ACP. Design Qualitative cross-sectional study. Setting Community Participants Sixty-three community dwelling persons age ≥ 65 years and 30 caregivers with experience as surrogate decision-makers. Measurements In focus groups conducted separately with older persons and with caregivers, participants were asked to discuss ways they had planned for future declines in health and why they had or had not engaged in such planning. Transcripts were analyzed using grounded theory. Results Four themes illustrated the potential of applying models of health behavior change to improve ACP. 1) Participants demonstrated variable readiness to engage in ACP and could be in different stages of readiness for different components of ACP, including consideration of treatment goals, completion of advance directives, and communication with families and physicians. 2) Participants identified a wide range of benefits of and barriers to ACP. 3) Participants used a variety of processes of change to progress through stages of readiness, and ACP was only one of a broader set of behaviors that participants engaged in to prepare for declines in their health or for death. 4) Experience with healthcare decision-making for loved ones was a strong influence on perceptions of susceptibility and engagement in ACP. Discussion The variability in participants' readiness, barriers and benefits, perceptions of susceptibility, and use of processes to increase readiness_for participating in each component of ACP suggests the utility of tailored, stage-specific interventions based on individualized assessments to improve ACP. PMID:19682120

  16. Advances in understanding the cell types and approaches used for generating induced pluripotent stem cells.

    PubMed

    Li, Jun; Song, Wei; Pan, Guangjin; Zhou, Jun

    2014-07-19

    Successfully reprogramming somatic cells to a pluripotent state generates induced pluripotent stem (iPS) cells (or iPSCs), which have extensive self-renewal capacity like embryonic stem cells (ESCs). iPSCs can also generate daughter cells that can further undergo differentiation into various lineages or terminally differentiate to reach their final functional state. The discovery of how to produce iPSCs opened a new field of stem cell research with both intellectual and therapeutic benefits. The huge potential implications of disease-specific or patient-specific iPSCs have impelled scientists to solve problems hindering their applications in clinical medicine, especially the issues of convenience and safety. To determine the range of tissue types amenable to reprogramming as well as their particular characteristics, cells from three embryonic germ layers have been assessed, and the advantages that some tissue origins have over fibroblast origins concerning efficiency and accessibility have been elucidated. To provide safe iPSCs in an efficient and convenient way, the delivery systems and combinations of inducing factors as well as the chemicals used to generate iPSCs have also been significantly improved in addition to the efforts on finding better donor cells. Currently, iPSCs can be generated without c-Myc and Klf4 oncogenes, and non-viral delivery integration-free chemically mediated reprogramming methods have been successfully employed with relatively satisfactory efficiency. This paper will review recent advances in iPS technology by highlighting tissue origin and generation of iPSCs. The obstacles that need to be overcome for clinical applications of iPSCs are also discussed.

  17. ADVANCING THE UNDERSTANDING OF BEHAVIORS ASSOCIATED WITH BACILLE CALMETTE GUÉRIN INFECTION USING MULTIVARIATE ANALYSIS

    PubMed Central

    Rodriguez-Zas, Sandra L.; Nixon, Scott E.; Lawson, Marcus A.; Mccusker, Robert H.; Southey, Bruce R.; O’Connor, Jason C.; Dantzer, Robert; Kelley, Keith W.

    2014-01-01

    Behavioral indicators in the murine Bacille Calmette Guérin (BCG) model of inflammation have been studied individually; however, the variability of the behaviors across BCG levels and the mouse-to-mouse variation within BCG-treatment group are only partially understood. The objectives of this study were: 1) to gain a comprehensive understanding of sickness and depression-like behaviors in a BCG model of inflammation using multivariate approaches, and 2) to explore behavioral differences between BCG-treatment groups and among mice within group. Adult mice were challenged with either 0mg (saline), 5mg or 10mg of BCG (BCG-treatment groups: BCG0, BCG5, or BCG10, respectively) at Day 0 of the experiment. Sickness indicators included body weight changes between Day 0 and Day 2 and between Day 2 and Day 5, and horizontal locomotor activity and vertical activity (rearing) measured at Day 6. Depression-like indicators included duration of immobility in the forced swim test and in the tail suspension test at Day 6 and sucrose consumption in the sucrose preference test at Day 7. The simultaneous consideration of complementary sickness and depression-like indicators enabled a more precise characterization of behavioral changes associated with BCG-treatment and of mouse-to-mouse variation, relative to the analysis of indicators individually. Univariate and multivariate analyses confirmed differences between BCG-treatment groups in weight change early on the trial. Significant differences between BCG-treatment groups in depression-like behaviors were still measurable after Day 5. The potential for multivariate models to account for the correlation between behavioral indicators and to augment the analytical precision relative to univariate models was demonstrated both for sickness and for depression-like indicators. Unsupervised learning approaches revealed the complementary information provided by the sickness and depression-like indicators considered. Supervised learning

  18. Recent advances in understanding the roles of transglutaminase 2 in alcoholic steatohepatitis.

    PubMed

    Tatsukawa, Hideki; Kojima, Soichi

    2010-02-22

    the present review article, we introduce these recent advances in knowledge with regard to the the roles of TG2 in alcoholic steatohepatitis.

  19. Advances in the understanding of mineral and bone metabolism in inflammatory bowel diseases

    PubMed Central

    Ghishan, Fayez K.

    2011-01-01

    Chronic inflammatory disorders such as inflammatory bowel diseases (IBDs) affect bone metabolism and are frequently associated with the presence of osteopenia, osteoporosis, and increased risk of fractures. Although several mechanisms may contribute to skeletal abnormalities in IBD patients, inflammation and inflammatory mediators such as TNF, IL-1β, and IL-6 may be the most critical. It is not clear whether the changes in bone metabolism leading to decreased mineral density are the result of decreased bone formation, increased bone resorption, or both, with varying results reported in experimental models of IBD and in pediatric and adult IBD patients. New data, including our own, challenge the conventional views, and contributes to the unraveling of an increasingly complex network of interactions leading to the inflammation-associated bone loss. Since nutritional interventions (dietary calcium and vitamin D supplementation) are of limited efficacy in IBD patients, understanding the pathophysiology of osteopenia and osteoporosis in Crohn's disease and ulcerative colitis is critical for the correct choice of available treatments or the development of new targeted therapies. In this review, we discuss current concepts explaining the effects of inflammation, inflammatory mediators and their signaling effectors on calcium and phosphate homeostasis, osteoblast and osteoclast function, and the potential limitations of vitamin D used as an immunomodulator and anabolic hormone in IBD. PMID:21088237

  20. Advancing the understanding of biogeography-diversity relationships of benthic microorganisms in the North Sea.

    PubMed

    Sapp, Melanie; Parker, Eleanor Ruth; Teal, Lorna Rachel; Schratzberger, Michaela

    2010-11-01

    Knowledge on the spatial distribution of prokaryotic taxa is an essential basis to understand microbial diversity and the factors shaping its patterns. Large-scale patterns of faunal distribution are thought to be influenced by physical environmental factors, whereas smaller scale spatial heterogeneity is maintained by species-specific life-history characteristics, the quantity and quality of food sources and local disturbances including both natural and man-induced events. However, it is still not clear which environmental parameters control the diversity and community structure of sedimentary microorganisms mediating important ecosystem processes. In this study, multiscale patterns were elucidated at seven stations in the Oyster Ground, North Sea (54°4'N/4°E), 100 m to 11 km apart. These were related to biotic (e.g. multicellular organisms) and abiotic parameters (e.g. organic carbon content in the sediment) to establish the relationship between the distribution of both bacterial and archaeal communities and their environment. A relatively high variability was detected at all scales for bacterial and archaeal communities, both of which were controlled by different suites of biotic and abiotic environmental variables. The bacterial community consisted mainly of members belonging to the Gammaproteobacteria and the Fibrobacteres/Acidobacteria group. Members of the Deltaproteobacteria, Bacteroidetes and Actinobacteria also contributed to the bacterial community. Euryarchaeota formed the majority of archaeal phylotypes together with three phylotypes belonging to the Crenarchaeota. © 2010 CEFAS. Journal compilation © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd.

  1. Advancements toward a systems level understanding of the human oral microbiome

    PubMed Central

    McLean, Jeffrey S.

    2014-01-01

    Oral microbes represent one of the most well studied microbial communities owing to the fact that they are a fundamental part of human development influencing health and disease, an easily accessible human microbiome, a highly structured and remarkably resilient biofilm as well as a model of bacteria-bacteria and bacteria-host interactions. In the last 80 years since oral plaque was first characterized for its functionally stable physiological properties such as the highly repeatable rapid pH decrease upon carbohydrate addition and subsequent recovery phase, the fundamental approaches to study the oral microbiome have cycled back and forth between community level investigations and characterizing individual model isolates. Since that time, many individual species have been well characterized and the development of the early plaque community, which involves many cell–cell binding interactions, has been carefully described. With high throughput sequencing enabling the enormous diversity of the oral cavity to be realized, a number of new challenges to progress were revealed. The large number of uncultivated oral species, the high interpersonal variability of taxonomic carriage and the possibility of multiple pathways to dysbiosis pose as major hurdles to obtain a systems level understanding from the community to the gene level. It is now possible however to start connecting the insights gained from single species with community wide approaches. This review will discuss some of the recent insights into the oral microbiome at a fundamental level, existing knowledge gaps, as well as challenges that have surfaced and the approaches to address them. PMID:25120956

  2. The Radiation Belt Storm Probes Mission: Advancing Our Understanding of the Earth's Radiation Belts

    NASA Technical Reports Server (NTRS)

    Sibeck, David; Kanekal, Shrikanth; Kessel, Ramona; Fox, Nicola; Mauk, Barry

    2012-01-01

    We describe NASA's Radiation Belt Storm Probe (RBSP) mission, whose primary science objective is to understand, ideally to the point of predictability, the dynamics of relativistic electrons and penetrating ions in the Earth's radiation belts resulting from variable solar activity. The overarching scientific questions addressed include: 1. the physical processes that produce radiation belt enhancement events, 2. the dominant mechanisms for relativistic electron loss, and 3. how the ring current and other geomagnetic processes affect radiation belt behavior. The RBSP mission comprises two spacecraft which will be launched during Fall 2012 into low inclination lapping equatorial orbits. The orbit periods are about 9 hours, with perigee altitudes and apogee radial distances of 600 km and 5.8 RE respectively. During the two-year primary mission, the spacecraft orbits precess once around the Earth and lap each other twice in each local time quadrant. The spacecraft are each equipped with identical comprehensive instrumentation packages to measure, electrons, ions and wave electric and magnetic fields. We provide an overview of the RBSP mission, onboard instrumentation and science prospects and invite scientific collaboration.

  3. Advancements toward a systems level understanding of the human oral microbiome.

    PubMed

    McLean, Jeffrey S

    2014-01-01

    Oral microbes represent one of the most well studied microbial communities owing to the fact that they are a fundamental part of human development influencing health and disease, an easily accessible human microbiome, a highly structured and remarkably resilient biofilm as well as a model of bacteria-bacteria and bacteria-host interactions. In the last 80 years since oral plaque was first characterized for its functionally stable physiological properties such as the highly repeatable rapid pH decrease upon carbohydrate addition and subsequent recovery phase, the fundamental approaches to study the oral microbiome have cycled back and forth between community level investigations and characterizing individual model isolates. Since that time, many individual species have been well characterized and the development of the early plaque community, which involves many cell-cell binding interactions, has been carefully described. With high throughput sequencing enabling the enormous diversity of the oral cavity to be realized, a number of new challenges to progress were revealed. The large number of uncultivated oral species, the high interpersonal variability of taxonomic carriage and the possibility of multiple pathways to dysbiosis pose as major hurdles to obtain a systems level understanding from the community to the gene level. It is now possible however to start connecting the insights gained from single species with community wide approaches. This review will discuss some of the recent insights into the oral microbiome at a fundamental level, existing knowledge gaps, as well as challenges that have surfaced and the approaches to address them.

  4. Advancing Integrated Understanding of Treeline Response to Environmental Change: the Alpine and Arctic Treeline Ecotone Network

    NASA Astrophysics Data System (ADS)

    Cairns, D. M.; Kueppers, L. M.; Millar, C. I.

    2013-12-01

    Upper elevation and northern treeline ecotones are boundary zones between forest and arctic or alpine tundra. Although presence of upright trees has defined the treeline per se, treeline is more accurately an ecotone structured by complex interactions among vegetation, soils, animals, climate, snow, topography, and disturbance regimes. The position and character of the treeline ecotone are important regulators of the land surface energy balance, biodiversity, and the cycling of carbon and water at high latitudes and elevations. The goal of the Alpine and Arctic Treeline Ecotone Network (AATE-Net) is to create a community of practice for treeline science across traditionally disparate fields of study. The objectives are to synthesize the state of knowledge around four scientific bottlenecks, identify pressing data gaps, broaden the perspectives of individual researchers, and foster a community-driven approach to alpine and Arctic treeline science. In pursuit of this goal and these objectives, the AATE-Net will bring together ecologists, ecosystem scientists, geographers, ecophysiologists, climatologists, hydrologists, and others with interests in treeline and ecotones in general to solidify our understanding of treeline dynamics across domains of time and space. Since treelines are globally distributed, interactions and partnerships with emerging treeline initiatives in Europe and elsewhere will be key components of the AATE-Net.

  5. Integration of Biological and Physical Sciences to Advance Ecological Understanding of Aquatic Ecosystems

    NASA Astrophysics Data System (ADS)

    Luce, C. H.; Buffington, J. M.; Rieman, B. E.; Dunham, J. B.; McKean, J. A.; Thurow, R. F.; Gutierrez-Teira, B.; Rosenberger, A. E.

    2005-05-01

    Conservation and restoration of freshwater stream and river habitats are important goals for land management and natural resources research. Several examples of research have emerged showing that many species are adapted to temporary habitat disruptions, but that these adaptations are sensitive to the spatial grain and extent of disturbance as well as to its duration. When viewed from this perspective, questions of timing, spatial pattern, and relevant scales emerge as critical issues. In contrast, much regulation, management, and research remains tied to pollutant loading paradigms that are insensitive to either time or space scales. It is becoming clear that research is needed to examine questions and hypotheses about how physical processes affect ecological processes. Two overarching questions concisely frame the scientific issues: 1) How do we quantify physical watershed processes in a way that is meaningful to biological and ecological processes, and 2) how does the answer to that question vary with changing spatial and temporal scales? A joint understanding of scaling characteristics of physical process and the plasticity of aquatic species will be needed to accomplish this research; hence a strong need exists for integrative and collaborative development. Considering conservation biology problems in this fashion can lead to creative and non-obvious solutions because the integrated system has important non-linearities and feedbacks related to a biological system that has responded to substantial natural variability in the past. We propose that research beginning with ecological theories and principles followed with a structured examination of each physical process as related to the specific ecological theories is a strong approach to developing the necessary science, and such an approach may form a basis for development of scaling theories of hydrologic and geomorphic process. We illustrate the approach with several examples.

  6. Advancing Understanding of Multiple-Land-Use Impacts on Urban Floodplain Groundwater Processes

    NASA Astrophysics Data System (ADS)

    Kellner, R. E.; Hubbart, J. A.

    2016-12-01

    Considering the increasing number of mixed-land-use watersheds globally, and dependence of communities on groundwater resources, there is an ongoing urgent need to improve quantitative understanding of land-use impacts on floodplain groundwater regimes. A study was implemented in Missouri, USA, investigating a remnant bottomland hardwood forest (BHF) and a historical agricultural field (Ag). A gridded sampling design was used to monitor continuous, automated, in situ shallow groundwater depth, to facilitate detailed spatiotemporal analysis of water table response to precipitation events, and calculation of groundwater flow via a Darcian model. Groundwater level data were collected at 30 min. intervals for the duration of the 2011-2014 water years. Results show significantly (p<0.001) greater magnitude water table response at the Ag site, relative to the BHF. The Ag water table also responded to a greater number of precipitation events (including smaller events), and responded more quickly to events than the BHF, indicating reduced relative flood attenuation and routing capacity. Groundwater flow results indicate a significantly (p<0.001) more dynamic and seasonally-responsive flow regime at the BHF, with higher maximum and lower minimum flow values, relative to the Ag site. Moreover, the BHF showed greater magnitude, longer duration, and more frequent base-flow reversals, indicating greater stream-buffering and high-flow attenuation capacity, relative to the Ag site. Results are by majority attributable to greater rates of plant water use by woody vegetation and preferential subsurface flow at the BHF site. Collectively, results suggest greater flood attenuation capacity and streamwater buffering potential by the BHF floodplain, relative to the Ag. Observed differences highlight the various impacts of forest vegetation on groundwater regimes and emphasize the benefit of floodplain forests as a water resource management tool in mixed-land-use urbanized watersheds.

  7. Advances in understanding the acute lymphoblastic leukemia bone marrow microenvironment: From biology to therapeutic targeting.

    PubMed

    Chiarini, Francesca; Lonetti, Annalisa; Evangelisti, Camilla; Buontempo, Francesca; Orsini, Ester; Evangelisti, Cecilia; Cappellini, Alessandra; Neri, Luca M; McCubrey, James A; Martelli, Alberto M

    2016-03-01

    The bone marrow (BM) microenvironment regulates the properties of healthy hematopoietic stem cells (HSCs) localized in specific niches. Two distinct microenvironmental niches have been identified in the BM, the "osteoblastic (endosteal)" and "vascular" niches. Nevertheless, these niches provide sanctuaries where subsets of leukemic cells escape chemotherapy-induced death and acquire a drug-resistant phenotype. Moreover, it is emerging that leukemia cells are able to remodel the BM niches into malignant niches which better support neoplastic cell survival and proliferation. This review focuses on the cellular and molecular biology of microenvironment/leukemia interactions in acute lymphoblastic leukemia (ALL) of both B- and T-cell lineage. We shall also highlight the emerging role of exosomes/microvesicles as efficient messengers for cell-to-cell communication in leukemia settings. Studies on the interactions between the BM microenvironment and ALL cells have led to the discovery of potential therapeutic targets which include cytokines/chemokines and their receptors, adhesion molecules, signal transduction pathways, and hypoxia-related proteins. The complex interplays between leukemic cells and BM microenvironment components provide a rationale for innovative, molecularly targeted therapies, designed to improve ALL patient outcome. A better understanding of the contribution of the BM microenvironment to the process of leukemogenesis and leukemia persistence after initial remission, may provide new targets that will allow destruction of leukemia cells without adversely affecting healthy HSCs. This article is part of a Special Issue entitled: Tumor Microenvironment Regulation of Cancer Cell Survival, Metastasis,Inflammation, and Immune Surveillance edited by Peter Ruvolo and Gregg L. Semenza. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Advances in Understanding Mating Type Gene Organization in the Mushroom-Forming Fungus Flammulina velutipes

    PubMed Central

    Wang, Wei; Lian, Lingdan; Xu, Ping; Chou, Tiansheng; Mukhtar, Irum; Osakina, Aron; Waqas, Muhammad; Chen, Bingzhi; Liu, Xinrui; Liu, Fang; Xie, Baogui; van Peer, Arend F.

    2016-01-01

    The initiation of sexual development in the important edible and medicinal mushroom Flammulina velutipes is controlled by special genes at two different, independent, mating type (MAT) loci: HD and PR. We expanded our understanding of the F. velutipes mating type system by analyzing the MAT loci from a series of strains. The HD locus of F. velutipes houses homeodomain genes (Hd genes) on two separated locations: sublocus HD-a and HD-b. The HD-b subloci contained strain-specific Hd1/Hd2 gene pairs, and crosses between strains with different HD-b subloci indicated a role in mating. The function of the HD-a sublocus remained undecided. Many, but not all strains contained the same conserved Hd2 gene at the HD-a sublocus. The HD locus usually segregated as a whole, though we did detect one new HD locus with a HD-a sublocus from one parental strain, and a HD-b sublocus from the other. The PR locus of F. velutipes contained pheromone receptor (STE3) and pheromone precursor (Pp) genes at two locations, sublocus PR-a and PR-b. PR-a and PR-b both contained sets of strain-specific STE3 and Pp genes, indicating a role in mating. PR-a and PR-b cosegregated in our experiments. However, the identification of additional strains with identical PR-a, yet different PR-b subloci, demonstrated that PR subloci can recombine within the PR locus. In conclusion, at least three of the four MAT subloci seem to participate in mating, and new HD and PR loci can be generated through intralocus recombination in F. velutipes. PMID:27621376

  9. Recent Advances in Understanding Radiation Belt Dynamics in the Earth's Inner Zone and Slot Region

    NASA Astrophysics Data System (ADS)

    Li, X.

    2015-12-01

    Comprehensive measurements of the inner belt protons from the Relativistic Electron and Proton Telescope (REPT) onboard Van Allen Probes, in a geo-transfer-like orbit, revealed new features of inner belt protons in terms of their spectrum distribution, spatial distribution, pitch angle distribution, and their different source populations. Concurrent measurements from the Relativistic Electron and Proton Telescope integrated little experiment (REPTile) on board Colorado Student Space Weather Experiment (CSSWE) CubeSat, in a highly inclined low Earth orbit, and REPT demonstrated that there exist sub-MeV electrons in the inner belt and their flux level is orders of magnitude higher than the background associated with the inner belt protons, while higher energy electron (>1.6 MeV) measurements cannot be distinguished from the background. Analysis on sub-MeV electrons data in the inner belt and slot region from the Magnetic Electron Ion Spectrometer (MagEIS) on board Van Allen Probes revealed rather complicated pitch angle distribution of these energetic electrons, with the 90 deg-minimum (butterfly) pitch angle distribution dominating near the magnetic equator. Furthermore, it is clearly shown from MagEIS measurements that 10s - 100s keV electrons are commonly seen penetrating into the inner belt region during geomagnetic active times while protons of similar energies are hardly seen there. These are part of a summary of the most recent measurements and understanding of the dynamics of energetic particles in the inner zone and slot region to be exhibited and discussed in this presentation.

  10. Vulnerable self, poor understanding of others' minds, threat anticipation and cognitive biases as triggers for delusional experience in schizophrenia: a theoretical model.

    PubMed

    Salvatore, Giampaolo; Lysaker, Paul H; Popolo, Raffaele; Procacci, Michele; Carcione, Antonino; Dimaggio, Giancarlo

    2012-01-01

    It remains unclear what processes lead to the establishment of persecutory delusions in acute phases of schizophrenia. Recently, it has been argued that persecutory delusions arise from an interaction among a range of emotional, cognitive and social factors. In this work, we explored this possibility by first discussing the relevant aspects of recent theoretical models of the causes of persecutory delusions. Then, we offered an analysis of the literature, illustrated with clinical observations suggesting that persecutory delusions are triggered during stressful intersubjective transactions by the interactions of (a) an alteration in empathetic perspective taking and in pragmatic understanding of others' minds; (b) a perception/representation of the self as vulnerable or subordinate and of the other as dominant and threatening; and (c) a hyperfunctioning of the threat/self-protection system when faced with perceived danger. Implications for future research and treatment of people suffering from this symptom are discussed. Copyright © 2011 John Wiley & Sons, Ltd.

  11. Theoretical Grounding: The "Missing Link" in Suicide Research.

    ERIC Educational Resources Information Center

    Rogers, James R.

    2001-01-01

    Discusses the strengths and limitations of the current pragmatic focus of research in suicidology and presents an argument for theoretical grounding as a precursor for continued advancement in this area. Presents an existential-constructivist framework of "meaning creation" as a theoretical heuristic for understanding suicide. Outlines general…

  12. Use of the theoretical domains framework to further understanding of what influences application of fluoride varnish to children's teeth: a national survey of general dental practitioners in Scotland.

    PubMed

    Gnich, Wendy; Bonetti, Debbie; Sherriff, Andrea; Sharma, Shilpi; Conway, David I; Macpherson, Lorna M D

    2015-06-01

    Despite recent improvements in the oral health of Scotland's population, the persistence of childhood dental caries underscores a need to reduce the disease burden experienced by children living in Scotland. Application of fluoride varnish (FV) to children's teeth provides an evidence-based approach to achieving this goal. Despite policy, health service targets and professional recommendations supporting application, not all children receive FV in line with guidance. The objective of this study was to use the theoretical domains framework (TDF) to further an understanding of what may influence fluoride varnish application (FVA) in General Dental Practice in Scotland. A postal questionnaire assessing current behaviour (frequency of FVA) and theoretical domains (TDs) was sent to all General Dental Practitioners (GDPs) in Scotland. Correlations and linear regression models were used to examine the association between FVA and the TDs. One thousand and ninety (53.6%) eligible GDPs responded. Respondents reported applying FV more frequently to increased risk and younger children (aged 2-5 years). Higher scores in eight TDs (Knowledge, Social/professional role and identity, Beliefs about consequences, Motivation and goals, Environmental context and resources, Social influences, Emotion and Behavioural regulation) were associated with greater frequency of FVA. Four beliefs in particular appear to be driving GDPs' decision to apply FV (recognizing that FVA is a guideline recommended behaviour (Knowledge), that FVA is perceived as an important part of the GDPs' professional role (Professional role/identity), that FV is something parents want for their children (Social influences) and that FV is something GDPs really wanted to do (Emotion). The findings of this study support the use of the TDF as a tool to understand GDPs application of FV and suggest that a multifaceted intervention, targeting dental professionals and families, and more specifically those domains and items

  13. Advancing our understanding of plant adaptation to metal polluted environments - new insights from Biscutella laevigata

    NASA Astrophysics Data System (ADS)

    Babst-Kostecka, Alicja; Waldmann, Patrik; Frérot, Hélène; Vollenweider, Pierre

    2016-04-01

    The legacy of industrial pollution alters ecosystems, particularly at post-mining sites where metal trace elements have created toxic conditions that trigger rapid plant adaptation. Apart from the purely scientific merits, in-depth knowledge of the mechanisms underlying plant adaptation to metal contamination is beneficial for the economic and societal sectors because of its application in bioengineering (e.g. phytoremediation or biofortification). An important process is the evolution and/or enhancement of metal tolerance, a trait that has predominantly been studied by applying acute metal stress on species that allocate large quantities of certain metals to their foliage (so-called hyperaccumulators). As the vast majority of vascular plants does not hyperaccumulate metals, more efforts are needed to investigate non-hyperaccumulating species and thereby broaden understanding of biological mechanisms underlying metal tolerance. The pseudometallophyte Biscutella laevigata has shown potential in this respect, but its characteristics are insufficiently understood. We determined the zinc tolerance level and various plant responses to environmentally relevant zinc concentrations in ten metallicolous and non-metallicolous B. laevigata populations. In a two-phase hydroponic experiment, we scored multiple morphological and physiological traits (e.g. biomass, visible stress symptoms, element content in foliage) and assessed phenotypic variability within plant families. The structure of these quantitative traits was compared to that of neutral molecular markers to test, whether natural selection caused population differentiation in zinc tolerance. While all genotypes were tolerant compared to a zinc sensitive reference species, we found congruent trends toward higher tolerance in metallicolous compared to non-metallicolous plants. We identified the most indicative parameters for these differences and find that enhanced zinc tolerance in metallicolous populations is driven by

  14. Recent Advances in Understanding the Sources of Methylmercury to Coastal Waters

    NASA Astrophysics Data System (ADS)

    Mason, R. P.; Balcom, P.; Chen, C.; Gosnell, K. J.; Jonsson, S.; Mazrui, N.; Ortiz, V.; Seelen, E.; Schartup, A. T.; Sunderland, E. M.

    2015-12-01

    Understanding the sources of methylmercury (MeHg) to the food chain in coastal waters is important given the related health concerns from consumption of seafood containing elevated MeHg. While water column dissolved or particulate MeHg is the best predictor of bioaccumulation into pelagic organisms in coastal waters, there is debate concerning the dominant sources of MeHg to the water column, and how the relative importance of these sources vary with ecosystem characteristics. Potential sources include both external inputs from the watershed and offshore waters and internal sources (net methylation in sediments and the associated flux of MeHg to the water column and/or net MeHg production in the water column). We will report the results from our various studies in estuarine and coastal waters which have examined the distribution and partitioning of sediment and water column MeHg, and its formation and degradation, across a geographic range from Labrador, Canada to the Chesapeake Bay, USA. The ecosystems studied vary from shallow estuarine bays to deeper systems, and from salt wedge to tidally-dynamic systems. Additionally, both pristine and contaminated environments were examined. The studies examined the factors controlling the net production of MeHg in sediments, and in our more recent work, the potential formation of MeHg in the oxic water column of coastal waters. Sediment measurements (core and grab samples) included both solid phase and porewater MeHg and total mercury (HgT) and important ancillary parameters. Water column parameters included dissolved and particulate MeHg and HgT, TSS, nutrients, and DOC. Stable Hg isotope tracer incubations were used to assess the degree of methylation and demethylation in sediments and surface waters. Average suspended particle MeHg ranged from <5 to 120 pmol/g, and was 1-8% of HgT across sites. Mass balance estimates provide insights into the importance of external MeHg sources to coastal waters. We will use the

  15. Understanding what the public know and value about geoheritage sites in order to advance Earth science literacy

    NASA Astrophysics Data System (ADS)

    Vye, E. C.; Rose, W. I.

    2013-12-01

    With its impressive geology and rich cultural history, Michigan's Keweenaw Peninsula is ideally suited for Earth science education and geotourism initiatives, such as a Geopark. Geologic events that have shaped this region can be interpreted in such a way as to engage learners, not only through an intellectual connection to Earth science subject matter, but also through an emotional connection via culture, history, and sense of place. The notion that landscape is special because it is the sum total of all the interacting earth systems, including people as part of the biosphere, can be used to drive these initiatives as they affect one personally. It is speculated that most people in the Keweenaw have a basic understanding of the local cultural history and some understanding of geology. Advanced awareness and understanding of the geological significance of the Keweenaw stands to greatly enrich our community's sense of place and desire to advance further education and geotourism initiatives. It is anticipated that these initiatives will ultimately lead to increased Earth science literacy and understanding and recognition of one's own environs. This will aid in the further development of publications, teaching media, trails info, on-site museums, etc. Although the community has embraced geo-outreach thus far, it is germane to know what people value, what they know of the geology and how they connect to place. Results from semi-structured interviews administered with the aim and focus of determining what places are special to people, why they are special and how they formed will be presented in this paper. The results from this research will be used to direct the creation and continued development of geologic interpretation of our region. It is hoped that this understanding will reveal common misconceptions that can be used to improve interpretive material that not only addresses misconceptions but also connects the immediate past with the deep geologic past of the

  16. ‘It’s a can of worms’: understanding primary care practitioners’ behaviours in relation to HPV using the theoretical domains framework

    PubMed Central

    2012-01-01

    Background The relationship between infection with high-risk human papillomavirus (HPV) and cervical cancer is transforming cervical cancer prevention. HPV tests and vaccinations have recently become available. In Ireland, as elsewhere, primary care practitioners play a key role in prevention. ATHENS (A Trial of HPV Education and Support) aims to develop a theory-based intervention to support primary care practitioners in their HPV-related practice. This study, the first step in the intervention development process, aimed to: identify HPV-related clinical behaviours that the intervention will target; clarify general practitioners’ (GPs’) and practice nurses’ roles and responsibilities; and determine factors that potentially influence clinical behaviour. A secondary objective was to informally assess the utility of the Theoretical Domains Framework (TDF) in understanding clinical behaviours in an area with an evolving evidence-base. Methods In-depth semi-structured telephone interviews were conducted with GPs and practice nurses. The topic guide, which contained open questions and HPV-related clinical scenarios, was developed through literature review and clinical experience. Interview transcripts were content-analysed using the TDF as the coding framework. Results 19 GPs and 14 practice nurses were interviewed. The major HPV-related clinical behaviours were: initiating a discussion about HPV infection with female patients; offering/recommending HPV vaccination to appropriate patients; and answering patients’ questions about HPV testing. While the responsibility for taking smears was considered a female role, both male and female practitioners dealt with HPV-related issues. All 12 theoretical domains arose in relation to HPV infection; the domains judged to be most important were: knowledge, emotion, social influences, beliefs about capabilities and beliefs about consequences. Eleven domains emerged in relation to HPV vaccination, with beliefs about

  17. The catalytic synergetic effect of carbon nanotubes on CuO during advanced oxidation processes: A theoretical account

    NASA Astrophysics Data System (ADS)

    Qin, Wu; Wei, Li; Wang, Lei; Dong, Changqing; Xiao, Xianbin; Zheng, Zongming; Yang, Yongping

    2013-05-01

    Following our previous work on the synergy between graphene and catalyst particle [1], we discuss how carbon nanotubes (CNTs) affect the catalytic reactivity of CuO during advanced oxidation processes using density functional theory calculations. CNTs act as electron donor and regulate the electronic structure of CuO during each reaction step because the 2p orbitals of the C atoms hybridise with the 4d orbitals of the Cu atoms rather than the 2p orbitals of the O atoms. An electric field guides charge transfer through the interface between the CNTs and CuO, which modifies the electronic state of CuO/CNTs for catalytic reactions.

  18. Advancing Our Understanding of the Link between Statistical Learning and Language Acquisition: The Need for Longitudinal Data.

    PubMed

    Arciuli, Joanne; Torkildsen, Janne von Koss

    2012-01-01

    Mastery of language can be a struggle for some children. Amongst those that succeed in achieving this feat there is variability in proficiency. Cognitive scientists remain intrigued by this variation. A now substantial body of research suggests that language acquisition is underpinned by a child's capacity for statistical learning (SL). Moreover, a growing body of research has demonstrated that variability in SL is associated with variability in language proficiency. Yet, there is a striking lack of longitudinal data. To date, there has been no comprehensive investigation of whether a capacity for SL in young children is, in fact, associated with language proficiency in subsequent years. Here we review key studies that have led to the need for this longitudinal research. Advancing the language acquisition debate via longitudinal research has the potential to transform our understanding of typical development as well as disorders such as autism, specific language impairment, and dyslexia.

  19. An advanced understanding of the specific effects of xylan and surface lignin contents on enzymatic hydrolysis of lignocellulosic biomass.

    PubMed

    Ju, Xiaohui; Engelhard, Mark; Zhang, Xiao

    2013-03-01

    In this study, chemical pulping techniques were applied to create a set of biomass substrates with intact lignocellulosic fibers and controlled morphological and chemical properties to allow the investigation of the individual effects of xylan and surface lignin content on enzymatic hydrolysis. A high resolution X-ray photoelectron spectroscopy technique was established for quantifying surface lignin content on lignocellulosic biomass substrates. The results from this study show that, apart from its hindrance effect, xylan can facilitate cellulose fibril swelling and thus create more accessible surface area, which improves enzyme and substrate interactions. Surface lignin has a direct impact on enzyme adsorption kinetics and hydrolysis rate. Advanced understanding of xylan and surface lignin effects provides critical information for developing more effective biomass conversion process. Published by Elsevier Ltd.

  20. Role of extrahepatic UDP-glucuronosyltransferase 1A1: advances in understanding breast milk-induced neonatal hyperbilirubinemia

    PubMed Central

    Fujiwara, Ryoichi; Maruo, Yoshihiro; Chen, Shujuan; Tukey, Robert H.

    2015-01-01

    Newborns commonly develop physiological hyperbilirubinemia (also known as jaundice). With increased bilirubin levels being observed in breast-fed infants, breast-feeding has been recognized as a contributing factor for the development of neonatal hyperbilirubinemia. Bilirubin undergoes selective metabolism by UDP-glucuronosyltransferase (UGT) 1A1 and becomes a water soluble glucuronide. Although several factors such as gestational age, dehydration and weight loss, and increased enterohepatic circulation have been associated with breast milk-induced jaundice (BMJ), deficiency in UGT1A1 expression is a known cause of BMJ. It is currently believed that unconjugated bilirubin is metabolized mainly in the liver. However, recent findings support the concept that extrahepatic tissues, such as small intestine and skin, contribute to bilirubin glucuronidation during the neonatal period. We will review the recent advances made towards understanding biological and molecular events impacting BMJ, especially regarding the role of extrahepatic UGT1A1 expression. PMID:26342858

  1. The Blackholic energy: long and short Gamma-Ray Bursts (New perspectives in physics and astrophysics from the theoretical understanding of Gamma-Ray Bursts, II)

    NASA Astrophysics Data System (ADS)

    Ruffini, Remo; Bernardini, Maria Grazia; Bianco, Carlo Luciano; Chardonnet, Pascal; Fraschetti, Federico; Gurzadyan, Vahe; Vitagliano, Luca; Xue, She-Sheng

    2005-08-01

    We outline the confluence of three novel theoretical fields in our modeling of Gamma-Ray Bursts (GRBs): 1) the ultrarelativistic regime of a shock front expanding with a Lorentz gamma factor ~ 300; 2) the quantum vacuum polarization process leading to an electron-positron plasma originating the shock front; and 3) the general relativistic process of energy extraction from a black hole originating the vacuum polarization process. There are two different classes of GRBs: the long GRBs and the short GRBs. We here address the issue of the long GRBs. The theoretical understanding of the long GRBs has led to the detailed description of their luminosities in fixed energy bands, of their spectral features and made also possible to probe the astrophysical scenario in which they originate. We are specially interested, in this report, to a subclass of long GRBs which appear to be accompanied by a supernova explosion. We are considering two specific examples: GRB980425/SN1998bw and GRB030329/SN2003dh. While these supernovae appear to have a standard energetics of 1049 ergs, the GRBs are highly variable and can have energetics 104 - 105 times larger than the ones of the supernovae. Moreover, many long GRBs occurs without the presence of a supernova. It is concluded that in no way a GRB can originate from a supernova. The precise theoretical understanding of the GRB luminosity we present evidence, in both these systems, the existence of an independent component in the X-ray emission, usually interpreted in the current literature as part of the GRB afterglow. This component has been observed by Chandra and XMM to have a strong decay on scale of months. We have named here these two sources respectively URCA-1 and URCA-2, in honor of the work that George Gamow and Mario Shoenberg did in 1939 in this town of Urca identifying the basic mechanism, the Urca processes, leading to the process of gravitational collapse and the formation of a neutron star and a supernova. The further

  2. Recent Advances in Understanding the Molecular Mechanisms Regulating the Root System Response to Phosphate Deficiency in Arabidopsis

    PubMed Central

    Bouain, Nadia; Doumas, Patrick; Rouached, Hatem

    2016-01-01

    Phosphorus (P) is an essential macronutrient for plant growth and development. Inorganic phosphate (Pi) is the major form of P taken up from the soil by plant roots. It is well established that under Pi deficiency condition, plant roots undergo striking morphological changes; mainly a reduction in primary root length while increase in lateral root length as well as root hair length and density. This typical phenotypic change reflects complex interactions with other nutrients such as iron, and involves the activity of a large spectrum of plant hormones. Although, several key proteins involved in the regulation of root growth under Pi-deficiency have been identified in Arabidopsis, how plants adapt roots system architecture in response to Pi availability remains an open question. In the current post-genomic era, state of the art technologies like high-throughput phenotyping and sequencing platforms,“omics” methods, together with the widespread use of system biology and genome-wide association studies will help to elucidate the genetic architectures of root growth on different Pi regimes. It is clear that the large-scale characterization of molecular systems will improve our understanding of nutrient stress phenotype and biology. Herein, we summarize the recent advances and future directions towards a better understanding of Arabidopsis root developmental programs functional under Pi deficiency. Such a progress is necessary to devise strategies to improve the Pi use efficiency in plants that is an important issue for agriculture. PMID:27499680

  3. Advances in understanding the surface chemistry of lignocellulosic biomass via time-of-flight secondary ion mass spectrometry

    DOE PAGES

    Tolbert, Allison K.; Ragauskas, Arthur J.

    2016-12-12

    Overcoming the natural recalcitrance of lignocellulosic biomass is necessary in order to efficiently convert biomass into biofuels or biomaterials and many times this requires some type of chemical pretreatment and/or biological treatment. While bulk chemical analysis is the traditional method of determining the impact a treatment has on biomass, the chemistry on the surface of the sample can differ from the bulk chemistry. Specifically, enzymes and microorganisms bind to the surface of the biomass and their efficiency could be greatly impacted by the chemistry of the surface. Therefore, it is important to study and understand the chemistry of the biomassmore » at the surface. Time-of- flight secondary ion mass spectrometry (ToF-SIMS) is a powerful tool that can spectrally and spatially analyze the surface chemistry of a sample. This review discusses the advances in understanding lignocellulosic biomass surface chemistry using the ToF-SIMS by addressing the instrument parameters, biomass sample preparation, and characteristic lignocellulosic ion fragmentation peaks along with their typical location in the plant cell wall. Furthermore, the use of the ToF-SIMS in detecting chemical changes due to chemical pretreatments, microbial treatments, and physical or genetic modifications is discussed along with possible future applications of the instrument in lignocellulosic biomass studies.« less

  4. Understanding high-density lipoprotein function in disease: recent advances in proteomics unravel the complexity of its composition and biology.

    PubMed

    Birner-Gruenberger, Ruth; Schittmayer, Matthias; Holzer, Michael; Marsche, Gunther

    2014-10-01

    Although the epidemiology of high-density lipoprotein (HDL) cholesterol and cardiovascular risk has been consistent, pharmacologic interventions to increase HDL-cholesterol by delaying HDL catabolism did not translate into reduction in cardiovascular risk. HDL particles are small, protein-rich when compared to other plasma lipoprotein classes. Latest progresses in proteomics technology have dramatically increased our understanding of proteins carried by HDL. In addition to proteins with well-established functions in lipid transport, iron transport proteins, members of the complement pathway, and proteins involved in immune function and acute phase response were repeatedly identified on HDL particles. With the unraveling of the complexity of the HDL proteome, different laboratories have started to monitor its changes in various disease states. In addition, dynamic aspects of HDL subgroups are being discovered. These recent studies clearly illustrate the promise of HDL proteomics for deriving new biomarkers for disease diagnosis and to measure the effectiveness of current and future treatment regimens. This review summarizes recent advances in proteomics and lipidomics helping to understand HDL function in health and disease. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Advanced Image Understanding.

    DTIC Science & Technology

    1981-12-01

    Applications to Computer Technology (McGraw-Hill, New York, 1967). . 3. B. Kruse, "System Architecture for Image Analysis," Chapter 7 of Structured ... Computer Vision, edited by S. Tanimoto and A. Klinger (Academic Press, 1980). 107

  6. Advances in understanding COPD

    PubMed Central

    Anderson, Gary P.

    2016-01-01

    In recent years, thousands of publications on chronic obstructive pulmonary disease (COPD) and its related biology have entered the world literature, reflecting the increasing scientific and medical interest in this devastating condition. This article is a selective review of several important emerging themes that offer the hope of creating new classes of COPD medicines. Whereas basic science is parsing molecular pathways in COPD, its comorbidities, and asthma COPD overlap syndrome (ACOS) with unprecedented sophistication, clinical translation is disappointingly slow. The article therefore also considers solutions to current difficulties that are impeding progress in translating insights from basic science into clinically useful treatments. PMID:27746898

  7. Advanced Understanding of Convection Initiation and Optimizing Cloud Seeding by Advanced Remote Sensing and Land Cover Modification over the United Arab Emirates

    NASA Astrophysics Data System (ADS)

    Wulfmeyer, V.; Behrendt, A.; Branch, O.; Schwitalla, T.

    2016-12-01

    A prerequisite for significant precipitation amounts is the presence of convergence zones. These are due to land surface heterogeneity, orography as well as mesoscale and synoptic scale circulations. Only, if these convergence zones are strong enough and interact with an upper level instability, deep convection can be initiated. For the understanding of convection initiation (CI) and optimal cloud seeding deployment, it is essential that these convergence zones are detected before clouds are developing in order to preempt the decisive microphysical processes for liquid water and ice formation. In this presentation, a new project on Optimizing Cloud Seeding by Advanced Remote Sensing and Land Cover Modification (OCAL) is introduced, which is funded by the United Arab Emirates Rain Enhancement Program (UAEREP). This project has two research components. The first component focuses on an improved detection and forecasting of convergence zones and CI by a) operation of scanning Doppler lidar and cloud radar systems during two seasonal field campaigns in orographic terrain and over the desert in the UAE, and b) advanced forecasting of convergence zones and CI with the WRF-NOAHMP model system. Nowcasting to short-range forecasting of convection will be improved by the assimilation of Doppler lidar and the UAE radar network data. For the latter, we will apply a new model forward operator developed at our institute. Forecast uncertainties will be assessed by ensemble simulations driven by ECMWF boundaries. The second research component of OCAL will study whether artificial modifications of land surface heterogeneity are possible through plantations or changes of terrain, leading to an amplification of convergence zones. This is based on our pioneering work on high-resolution modeling of the impact of plantations on weather and climate in arid regions. A specific design of the shape and location of plantations can lead to the formation of convergence zones, which can

  8. HIRS-AMTS satellite sounding system test - Theoretical and empirical vertical resolving power. [High resolution Infrared Radiation Sounder - Advanced Moisture and Temperature Sounder

    NASA Technical Reports Server (NTRS)

    Thompson, O. E.

    1982-01-01

    The present investigation is concerned with the vertical resolving power of satellite-borne temperature sounding instruments. Information is presented on the capabilities of the High Resolution Infrared Radiation Sounder (HIRS) and a proposed sounding instrument called the Advanced Moisture and Temperature Sounder (AMTS). Two quite different methods for assessing the vertical resolving power of satellite sounders are discussed. The first is the theoretical method of Conrath (1972) which was patterned after the work of Backus and Gilbert (1968) The Backus-Gilbert-Conrath (BGC) approach includes a formalism for deriving a retrieval algorithm for optimizing the vertical resolving power. However, a retrieval algorithm constructed in the BGC optimal fashion is not necessarily optimal as far as actual temperature retrievals are concerned. Thus, an independent criterion for vertical resolving power is discussed. The criterion is based on actual retrievals of signal structure in the temperature field.

  9. Advances in the Understanding of ELM Suppression by Resonant Magnetic Perturbations (RMPs) in DIII-D and Implications for ITER

    SciTech Connect

    Nazikian, R.

    2014-09-01

    Experiments on DIII-D have expanding the operating window for RMP ELM suppression to higher q95 with dominant electron heating and fully non-inductive current drive relevant to advanced modes of ITER operation. Robust ELM suppression has also been obtained with a reduced coil set, mitigating the risk of coil failure in maintaining ELM suppression in ITER. These results significantly expand the operating space and reduce risk for obtaining RMP ELM suppression in ITER. Efforts have also been made to search for 3D cause of ELM suppression. No internal non-axisymmetric structure is detected at the top of the pedestal, indicating that the dominant effect of the RMP is to produce an n=0 transport modification of the profiles. Linear two fluid MHD simulations using M3D-C1 indicate resonant field penetration and significant magnetic stochasticity at the top of the pedestal, consistent with the absence of detectable 3D structure in that region. A profile database was developed to compare the scaling of the pedestal and global confinement with the applied 3D field strength in ELM suppressed and ELM mitigated plasmas. The EPED pedestal model accurately predicts the measured pedestal pressure at the threshold of ELM suppression, increasing confidence in theoretical projections to ITER pedestal conditions. Both the H-factor (H(sub)98y2) and thermal energy confinement time do not degrade substantially with applied RMP fields near the threshold of ELM suppression, enhancing confidence in the compatibility of ITER high performance operation with RMP ELM suppression.

  10. Using grounded theory to generate a theoretical understanding of the effects of child custody policy on women's health promotion in the context of intimate partner violence.

    PubMed

    Wuest, Judith; Ford-Gilboe, Marilyn; Merritt-Gray, Marilyn; Lemire, Shannon

    2006-01-01

    Women's health is frequently influenced by social and structural factors, largely beyond women's control, and often entrenched in public policy. Although health is acknowledged to be socially determined, the ways that social conditions affect health are rarely explicated. Grounded theory is a useful method for discovering how structural conditions influence patterns of behavior. We used grounded theory to generate a theoretical understanding of how justice system policy and services related to child custody influence health promotion processes of women and their children after leaving abusive male partners/fathers. In two diverse Canadian provinces, we interviewed single mothers who had left abusive partners as well as frontline workers and policymakers in the justice system. We identified the key dimensions of policy and services that influence the ways in which women and their children promote their health in the context of varying levels of ongoing intrusion as information, eligibility, accessibility, timeliness, human resources, safety, and diversity. In this article, the interplay between theses policy and service dimensions and women's health promotion after leaving abusive partners is discussed and suggestions are made for strengthening "healthy" custody policy.

  11. A Theoretical and Synthetic Investigation of New Donors for Organic Electro-Optic Chromophores: Understanding the Effects of Structure and Substituents on Donor Strength

    NASA Astrophysics Data System (ADS)

    Phillips-Sylvain, Nathaniel

    Understanding of the intricate connection between shape, structure and property has al- lowed many challenges facing the adoption of organic chromophores for electro-optic (EO) applications to be overcome. Still, there is much to be learned about designing donors that localize electron density in the ground state, but not in the electronically polarized state to allow for enhanced charge transfer, and thus, large first-order molecular hyperpolarizability (beta). To address this, density functional theory has been used to evaluate a large number of potential donors based on alkyl, aryl, saturated and unsaturated heterocycles. These were coupled to the tricyanopyrroline (TCP) acceptor by a simple vinylic bridge to identify new high beta, high number density materials. Saturated heterocylces were found to off the largest improvements over traditional dialkyl donors, with the predicted systems rivaling much longer polyene-based chromophores with a trifluoromethyl, phenyl-tricyanofuran (CF 3PhTCF). Other potential candidates where based on diaryl amines donors which are a natural progression from previous heteroaryl chromophores. These systems were typified by a greater degree of localized electron density - by as much as 20% - at the donor and were found to exhibit characteristics that might described as a double-donor. Several novel chromophores based on these new donors were synthesized to verify the theoretical results and evaluate their potential for use in EO devices.

  12. From technological advances to biological understanding: The main steps toward high-precision RT in breast cancer.

    PubMed

    Leonardi, Maria Cristina; Ricotti, Rosalinda; Dicuonzo, Samantha; Cattani, Federica; Morra, Anna; Dell'Acqua, Veronica; Orecchia, Roberto; Jereczek-Fossa, Barbara Alicja

    2016-10-01

    Radiotherapy improves local control in breast cancer (BC) patients which increases overall survival in the long term. Improvements in treatment planning and delivery and a greater understanding of BC behaviour have laid the groundwork for high-precision radiotherapy, which is bound to further improve the therapeutic index. Precise identification of target volumes, better coverage and dose homogeneity have had a positive impact on toxicity and local control. The conformity of treatment dose due to three-dimensional radiotherapy and new techniques such as intensity modulated radiotherapy makes it possible to spare surrounding normal tissue. The widespread use of dose-volume constraints and histograms have increased awareness of toxicity. Real time image guidance has improved geometric precision and accuracy, together with the implementation of quality assurance programs. Advances in the precision of radiotherapy is also based on the choice of the appropriate fractionation and approach. Adaptive radiotherapy is not only a technical concept, but is also a biological concept based on the knowledge that different types of BC have distinctive patterns of locoregional spread. A greater understanding of cancer biology helps in choosing the treatment best suited to a particular situation. Biomarkers predictive of response play a crucial role. The combination of radiotherapy with molecular targeted therapies may enhance radiosensitivity, thus increasing the cytotoxic effects and improving treatment response. The appropriateness of an alternative fractionation, partial breast irradiation, dose escalating/de-escalating approaches, the extent of nodal irradiation have been examined for all the BC subtypes. The broadened concept of adaptive radiotherapy is vital to high-precision treatments.

  13. Recent advances in the understanding of how neuropeptide Y and α-melanocyte stimulating hormone function in adipose physiology

    PubMed Central

    Shipp, Steven L.; Cline, Mark A.; Gilbert, Elizabeth R.

    2016-01-01

    ABSTRACT Communication between the brain and the adipose tissue has been the focus of many studies in recent years, with the “brain-fat axis” identified as a system that orchestrates the assimilation and usage of energy to maintain body mass and adequate fat stores. It is now well-known that appetite-regulating peptides that were studied as neurotransmitters in the central nervous system can act both on the hypothalamus to regulate feeding behavior and also on the adipose tissue to modulate the storage of energy. Energy balance is thus partly controlled by factors that can alter both energy intake and storage/expenditure. Two such factors involved in these processes are neuropeptide Y (NPY) and α-melanocyte stimulating hormone (α-MSH). NPY, an orexigenic factor, is associated with promoting adipogenesis in both mammals and chickens, while α-MSH, an anorexigenic factor, stimulates lipolysis in rodents. There is also evidence of interaction between the 2 peptides. This review aims to summarize recent advances in the study of NPY and α-MSH regarding their role in adipose tissue physiology, with an emphasis on the cellular and molecular mechanisms. A greater understanding of the brain-fat axis and regulation of adiposity by bioactive peptides may provide insights on strategies to prevent or treat obesity and also enhance nutrient utilization efficiency in agriculturally-important species. PMID:27994947

  14. Commentary: Developmental connectomics to advance our understanding of typical and atypical brain development – Commentary on Vertes & Bullmore (2015)

    PubMed Central

    Graham, Alice M.; Fair, Damien A.

    2015-01-01

    Vértes and Bullmore's article lays a framework for applying connectomics, the study of brain function from the perspective of underlying network organization, to advance understanding of healthy and maladaptive brain development. They elucidate the power of connectomics for bridging both different levels of analysis (e.g. from synapses to brain regions) and multiple academic fields. In this commentary, we highlight important themes and remaining questions stemming from Vértes and Bullmore's work, including: (1) the application of connectomics in the context of integrating analyses across multiple spatial and temporal dimensions, (2) the extent to which connectomics might be applied in translational and clinical studies of development, (3) growth connectomics and the Developmental Origins of Health and Disease (DOHaD) hypothesis, and (4) the importance and complexity of sound methodological practices in applying connectomics to developmental and clinical science. Ongoing work in these areas will be important for fulfilling the promise of connectomics as a bridge between neuroscience, developmental science, and translational and clinical research. PMID:25714740

  15. Some recent advances on the study and understanding of the functional design of the avian lung: morphological and morphometric perspectives.

    PubMed

    Maina, J N

    2002-02-01

    The small highly aerobic avian species have morphometrically superior lungs while the large flightless ones have less well-refined lungs. Two parabronchial systems, i.e. the paleopulmo and neopulmo, occur in the lungs of relatively advanced birds. Although their evolution and development are not clear, understanding their presence is physiologically important particularly since the air- and blood flow patterns in them are different. Geometrically, the bulk air flow in the parabronchial lumen, i.e. in the longitudinal direction, and the flow of deoxygenated blood from the periphery, i.e. in a centripetal direction, are perpendicularly arranged to produce a cross-current relationship. Functionally, the blood capillaries in the avian lung constitute a multicapillary serial arterialization system. The amount of oxygen and carbon dioxide exchanged arises from many modest transactions that occur where air- and blood capillaries interface along the parabronchial lengths, an additive process that greatly enhances the respiratory efficiency. In some species of birds, an epithelial tumescence occurs at the terminal part of the extrapulmonary primary bronchi (EPPB). The swelling narrows the EPPB, conceivably allowing the shunting of inspired air across the openings of the medioventral secondary bronchi, i.e. inspiratory aerodynamic valving. The defence stratagems in the avian lung differ from those of mammals: fewer surface (free) macrophages (SMs) occur, the epithelial cells that line the atria and infundibula are phagocytic, a large population of subepithelial macrophages is present and pulmonary intravascular macrophages exist. This complex defence inventory may explain the paucity of SMs in the avian lung.

  16. Hydrological partitioning in the critical zone: Recent advances and opportunities for developing transferable understanding of water cycle dynamics

    NASA Astrophysics Data System (ADS)

    Brooks, Paul D.; Chorover, Jon; Fan, Ying; Godsey, Sarah E.; Maxwell, Reed M.; McNamara, James P.; Tague, Christina

    2015-09-01

    Hydrology is an integrative discipline linking the broad array of water-related research with physical, ecological, and social sciences. The increasing breadth of hydrological research, often where subdisciplines of hydrology partner with related sciences, reflects the central importance of water to environmental science, while highlighting the fractured nature of the discipline itself. This lack of coordination among hydrologic subdisciplines has hindered the development of hydrologic theory and integrated models capable of predicting hydrologic partitioning across time and space. The recent development of the concept of the critical zone (CZ), an open system extending from the top of the canopy to the base of groundwater, brings together multiple hydrological subdisciplines with related physical and ecological sciences. Observations obtained by CZ researchers provide a diverse range of complementary process and structural data to evaluate both conceptual and numerical models. Consequently, a cross-site focus on "critical zone hydrology" has potential to advance the discipline of hydrology and to facilitate the transition of CZ observatories into a research network with immediate societal relevance. Here we review recent work in catchment hydrology and hydrochemistry, hydrogeology, and ecohydrology that highlights a common knowledge gap in how precipitation is partitioned in the critical zone: "how is the amount, routing, and residence time of water in the subsurface related to the biogeophysical structure of the CZ?" Addressing this question will require coordination among hydrologic subdisciplines and interfacing sciences, and catalyze rapid progress in understanding current CZ structure and predicting how climate and land cover changes will affect hydrologic partitioning.

  17. Recent advances in bio-logging science: Technologies and methods for understanding animal behaviour and physiology and their environments

    NASA Astrophysics Data System (ADS)

    Evans, K.; Lea, M.-A.; Patterson, T. A.

    2013-04-01

    The deployment of an ever-evolving array of animal-borne telemetry and data logging devices is rapidly increasing our understanding of the movement, behaviour and physiology of a variety species and the complex, and often highly dynamic, environments they use and respond to. The rapid rate at which new technologies, improvements to current technologies and new analytical techniques are being developed has meant that movements, behaviour and physiological processes are being quantified at finer spatial and temporal scales than ever before. The Fourth International Symposium on Bio-logging Science, held on 14-18 March in Hobart, Australia, brought together scientists across multiple disciplines to discuss the latest innovations in technology, applications and analytical techniques in bio-logging science, building on research presented at three previous conferences. Here we present an update on the state of bio-logging research and provide some views on the future of this field of research. Papers were grouped into five theme areas: (i) Southern Ocean ecosystems; (ii) fishery and biodiversity management applications; (iii) from individuals to populations—inferences of population dynamics from individuals; (iv) conservation biology and (v) habitat modelling. Papers reflected wider uptake of newer technologies, with a greater proportion of studies utilising accelerometry and incorporating advances in statistical modelling of behaviour and habitats, especially via state space modelling methods. Environmental data collected by tags at increasing accuracies are now having wider application beyond the bio-logging community, providing important oceanographic data from regions difficult to sample using traditional methodologies. Partnerships between multiple organisations are also now enabling regional assessments of species movements, behaviour and physiology at population scales and will continue to be important for applying bio-logging technologies to species

  18. Advancing understanding of the sustainability of lay health advisor (LHA) programs for African-American women in community settings.

    PubMed

    Shelton, Rachel C; Charles, Thana-Ashley; Dunston, Sheba King; Jandorf, Lina; Erwin, Deborah O

    2017-03-23

    Lay health advisor (LHA) programs have made strong contributions towards the elimination of health disparities and are increasingly being implemented to promote health and prevent disease. Developed in collaboration with African-American survivors, the National Witness Project (NWP) is an evidence-based, community-led LHA program that improves cancer screening among African-American women. NWP has been successfully disseminated, replicated, and implemented nationally in over 40 sites in 22 states in diverse community settings, reaching over 15,000 women annually. We sought to advance understanding of barriers and facilitators to the long-term implementation and sustainability of LHA programs in community settings from the viewpoint of the LHAs, as well as the broader impact of the program on African-American communities and LHAs. In the context of a mixed-methods study, in-depth telephone interviews were conducted among 76 African-American LHAs at eight NWP sites at baseline and 12-18 months later, between 2010 and 2013. Qualitative data provides insight into inner and outer contextual factors (e.g., community partnerships, site leadership, funding), implementation processes (e.g., training), as well as characteristics of the intervention (e.g., perceived need and fit in African-American community) and LHAs (e.g., motivations, burnout) that are perceived to impact the continued implementation and sustainability of NWP. Factors at the contextual levels and related to motivations of LHAs are critical to the sustainability of LHA programs. We discuss how findings are used to inform (1) the development of the LHA Sustainability Framework and (2) strategies to support the continued implementation and sustainability of evidence-based LHA interventions in community settings.

  19. Progress report on understanding AFIS seed coat nep levels in pre-opened slivers on the Advanced Fiber Information System (AFIS)

    USDA-ARS?s Scientific Manuscript database

    The Advanced Fiber Information System (AFIS) is utilized in this segment of the research project to study how seed coat neps are measured. A patent search was conducted, and studied to assist with the understanding of the AFIS measurement of this impurity in raw cotton. The older AFIS 2 is primari...

  20. High-frequency HYDRO-geophysical observations for an advanced understanding of clayey landSLIDES: the HYDROSLIDE research project

    NASA Astrophysics Data System (ADS)

    Malet, Jean-Philippe; Supper, Robert; Flores-Orozco, Adrian; Gautier, Stéphanie; Bogaard, Thom

    2017-04-01

    As a consequence of change in hydrological cycles and the increase of exposed goods, the risk of landslides is globally growing all over the world. As a consequence, short-time landslide prediction is a fundamental tool for risk mitigation. To this aim, real-time monitoring and interpretation methods aiming at a full exploitation of the available landslide information are needed, including further development of sensor technology and use of advanced numerical modeling. The most commonly used warning parameters are direct measurements of slope displacement and pore-water pressures. However, recent research on landslide controlled by slope hydrology has shown that other parameters (e.g. soil moisture) can be used and other methods (e.g. electrical resistivity tomography, electrical spontaneous potential) are available, which might give indications on triggering even before an actual displacement is measureable and thus could possibly be used as physical precursors for short-term warning. The CNRS - Ecole et Observatoire des Sciences de la Terre (EOST) and the Geological Survey of Austria - Geophysical Division (GBA) started successfully to evaluate time-lapse resistivity measurements for monitoring changes in water content/flows in landslides at different monitoring sites. At the same period, CNRS also started to establish the French Observatory on Landslides (OMIV: omiv.unistra.fr), which task is the long term monitoring and data sharing of landslide parameters (geodesy, hydrology, seismic). Results from these projects proved that electrical resistivity monitoring can be successfully applied to detect changes in water storage and to understand water circulation in complex landslide bodies. However, especially for clayey landslides, this method is only applicable with limitation, since the resistivity of clays shows almost the same values as the resistivity of the saturated soil (15-20 O.m). Consequently, the change in water content expressed in the electrical