262 research outputs found

    Dynamical Fermions with Fat Links

    Get PDF
    We present and test a new method for simulating dynamical fermions with fat links. Our construction is based on the introduction of auxiliary but dynamical gauge fields and works with any fermionic action and can be combined with any fermionic updating. In our simulation we use an over-relaxation step which makes it effective. For four flavors of staggered fermions first results indicate that flavor symmetry at a lattice spacing a~0.2 fm is restored to a few percent. With the standard action this amount of flavor symmetry restoration is achieved at a~0.07 fm. We estimate that the overall computational cost is reduced by at least a factor 10.Comment: 11 pages, 4 figures, detailed description of over-relaxation and references added, figures with more statistic

    Initiating the dialogue between infant mental health and family therapy: a qualitative inquiry and recommendations

    Get PDF
    This qualitative study explores infant-family mental health experts' perspectives and experiences regarding the inclusion of infants in the family therapy setting. Infant socioemotional development is relational in nature and evolves in the context of both dyadic attachment relationships and broader multi-person co-parenting systems. Given this, we sought to understand why family therapy interventions involving families with infants rarely include the infant in a triangular or family systemic approach. Interviews were completed by clinical and/or research experts whose work integrates tenets of both infant mental health (IMH) and family theory and therapy. All interviewees brought at least 5 years of expertise and were actively engaged in the field. Interviewees expressed consistent beliefs that infants have a rightful and helpful place in family therapy approaches. They maintained that infants' innate social drive and communicative capacities position them to make meaningful and clinically significant contributions within family and systemic psychotherapy contexts. Noting that infants have remained on the periphery of these practices, experts advocated expansion and greater integration between IMH and family therapy, while preserving each field's distinctive identity. Experts reported that the interplay between IMH and family therapy fields has been uni-directional as family systems concepts are embedded within IMH approaches, but few IMH premises are incorporated in mainstream family therapy practices. The disconnect was attributed to multiple factors, including graduate and professional training and theoretical, clinical, research, and sociocultural barriers, which were mutually reinforcing. Experts also identified clinical gains for both infants and family members when infants were meaningfully included in family interventions. Common ground was identified between the disciplines, with a belief that relationally distressed young children and parents are best served by clinical engagement with their network of relationships. Results call for greater collaboration between disciplines to challenge existing traditions and to more fully include infants in mainstream family therapy. Recommendations for integration of family therapy and IMH in clinical, theoretical, research, training, and sociocultural domains are offered

    Drought as an emergent driver of ecological transformation in the twenty-first century

    Get PDF
    Under climate change, ecosystems are experiencing novel drought regimes, often in combination with stressors that reduce resilience and amplify drought\u27s impacts. Consequently, drought appears increasingly likely to push systems beyond important physiological and ecological thresholds, resulting in substantial changes in ecosystem characteristics persisting long after drought ends (i.e., ecological transformation). In the present article, we clarify how drought can lead to transformation across a wide variety of ecosystems including forests, woodlands, and grasslands. Specifically, we describe how climate change alters drought regimes and how this translates to impacts on plant population growth, either directly or through drought\u27s interactions with factors such as land management, biotic interactions, and other disturbances. We emphasize how interactions among mechanisms can inhibit postdrought recovery and can shift trajectories toward alternate states. Providing a holistic picture of how drought initiates long-term change supports the development of risk assessments, predictive models, and management strategies, enhancing preparedness for a complex and growing challenge

    BOWIE-ALIGN: A JWST comparative survey of aligned versus misaligned hot Jupiters to test the dependence of atmospheric composition on migration history

    Get PDF
    A primary objective of exoplanet atmosphere characterization is to learn about planet formation and evolution, however, this is challenged by degeneracies. To determine whether differences in atmospheric composition can be reliably traced to differences in evolution, we are undertaking a transmission spectroscopy survey with JWST to compare the compositions of a sample of hot Jupiters that have different orbital alignments around F stars above the Kraft break. Under the assumption that aligned planets migrate through the inner disc, while misaligned planets migrate after disc dispersal, the act of migrating through the inner disc should cause a measurable difference in the C/O between aligned and misaligned planets. We expect the amplitude and sign of this difference to depend on the amount of planetesimal accretion and whether silicates accreted from the inner disc release their oxygen. Here, we identify all known exoplanets that are suitable for testing this hypothesis, describe our JWST survey, and use noise simulations and atmospheric retrievals to estimate our survey’s sensitivity. With the selected sample of four aligned and four misaligned hot Jupiters, we will be sensitive to the predicted differences in C/O between aligned and misaligned hot Jupiters for a wide range of model scenarios

    The impact of egg incubation temperature on the personality of oviparous reptiles

    Get PDF
    Personality traits, defined as differences in the behavior of individual animals of the same species that are consistent over time and context, such as ‘boldness,’ have been shown to be both heritable and be influenced by external factors, such as predation pressure. Currently, we know very little about the role that early environmental factors have upon personality. Thus, we investigated the impact of incubation temperature upon the boldness on an oviparous reptile, the bearded dragon (Pogona vitticeps). Eggs, from one clutch, were incubated at two different average temperatures within the normal range. After hatching the lizards were raised under the same environmental conditions. Novel object and novel environment tests were used to assess personality. Each test was repeated in both the short term and the long term. The results revealed that incubation temperature did impact upon ‘boldness’ but only in the short term and suggests that, rather than influencing personality, incubation temperature may have an effect on the development of behavioral of oviparous reptiles at different stages across ontogeny

    Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.

    Get PDF
    Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis

    Search for CP Violation in the Decay Z -> b (b bar) g

    Full text link
    About three million hadronic decays of the Z collected by ALEPH in the years 1991-1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z -> b \bar{b} g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, h^b=h^AbgVbh^VbgAb{\hat{h}}_b = {\hat{h}}_{Ab}g_{Vb}-{\hat{h}}_{Vb}g_{Ab} and hb=h^Vb2+h^Ab2h^{\ast}_b = \sqrt{\hat{h}_{Vb}^{2}+\hat{h}_{Ab}^{2}}, limits of \hat{h}_b < 0.59and and h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st
    corecore