399 research outputs found
Massive Vector Scattering in Lee-Wick Gauge Theory
We demonstrate that amplitudes describing scattering of longitudinally
polarized massive vector bosons present in non-Abelian Lee-Wick gauge theory do
not grow with energy and, hence, satisfy the constraints imposed by
perturbative unitarity. This result contrasts with the widely-known violation
of perturbative unitarity in the standard model with a very heavy Higgs. Our
conclusions are valid to all orders of perturbation theory and depend on the
existence of a formulation of the theory in which all operators are of
dimension four or less. This can be thought of as a restriction on the kinds of
higher dimension operator which can be included in the higher derivative
formulation of the theory.Comment: 11 pages, no figure
Fruit and Leaf Sensing for Continuous Detection of Nectarine Water Status
Continuous assessment of plant water status indicators might provide the most precise information for irrigation management and automation, as plants represent an interface between soil and atmosphere. This study investigates the relationship of plant water status to continuous fruit diameter (FD) and inverse leaf turgor pressure rates (pp) in nectarine trees [Prunus persica (L.) Batsch] throughout fruit development. The influence of deficit irrigation treatments on stem (Ψstem) and leaf water potential, leaf relative water content, leaf hydraulic conductance and fruit growth was studied across the stages of double-sigmoidal fruit development in 'September Bright' nectarines. Fruit relative growth rate (RGR) and leaf pressure change rate (RPCR) were derived from FD and pp to represent rates of water in- and outflows in the organs, respectively. Continuous RGR and RPCR dynamics were independently and combinedly related to plant water status and environmental variables. The independent use of RGR and RPCR yielded significant associations with midday Ψstem, the most representative index of tree water status in anisohydric species. However, the combined use of nocturnal fruit and leaf parameters unveiled an even more significant relationship with Ψstem, suggesting a different fruit-to-leaf water balance in response to pronounced water deficit. In conclusion, we highlight the suitability of a multi-organ sensing approach for improved prediction of tree water status
Technology as Social Instruction: Ursula Franklin and the Dematerialized Fashion Marketplace
COVID-19 necessitated the accelerated growth of a powerful and aggressive new form of fashion retail: online, device-based consumption. This online migration has radically altered modern retail, from invasive marketing to engage consumers, through virtual selection and ultimately the dematerialization of the body and understanding of the self in relation to others. Canadian physicist and technology theorist Dr Ursula Franklin provided valuable insight into the processes wherein emergent technology and human behaviours enmesh within quotidian engagements. In her (brilliant) 1989 Massey College lecture series The Real World of Technology (1999) stated of the adoption of nascent technologies that “Many technological innovations have been introduced in order to change the boundaries of human and social activities with respect to time and space” (194). Time and space have certainly been disrupted with the technological migration of the boutique, and this virtualizing of fashion has in turn dematerialized garments completely. Thus, the engagement is primarily with the technology and not the tactile. The impacts of this are staggering as current models used for fashion manufacturing are deeply imbricated into transglobal “Fast Fashion” supply chains, a process extremely harmful to both workers and environment
Neutrino Masses in the Lee-Wick Standard Model
Recently, an extension of the standard model based on ideas of Lee and Wick
has been discussed. This theory is free of quadratic divergences and hence has
a Higgs mass that is stable against radiative corrections. Here, we address the
question of whether or not it is possible to couple very heavy particles, with
masses much greater than the weak scale, to the Lee-Wick standard model degrees
of freedom and still preserve the stability of the weak scale. We show that in
the LW-standard model the familiar see-saw mechanism for generating neutrino
masses preserves the solution to the hierarchy puzzle provided by the higher
derivative terms. The very heavy right handed neutrinos do not destabilize the
Higgs mass. We give an example of new heavy degrees of freedom that would
destabilize the hierarchy, and discuss a general mechanism for coupling other
heavy degrees of freedom to the Higgs doublet while preserving the hierarchy.Comment: 7 pages, 1 figur
Minimal Extension of the Standard Model Scalar Sector
The minimal extension of the scalar sector of the standard model contains an
additional real scalar field with no gauge quantum numbers. Such a field does
not couple to the quarks and leptons directly but rather through its mixing
with the standard model Higgs field. We examine the phenomenology of this model
focusing on the region of parameter space where the new scalar particle is
significantly lighter than the usual Higgs scalar and has small mixing with it.
In this region of parameter space most of the properties of the additional
scalar particle are independent of the details of the scalar potential.
Furthermore the properties of the scalar that is mostly the standard model
Higgs can be drastically modified since its dominant branching ratio may be to
a pair of the new lighter scalars.Comment: 4 pages, 2 figure
Case report of spuriously low sodium and calcium in a 36-year-old male in primary care
An unseparated serum specimen for a 36-year-old male was received from primary care. The specimen arrived in the laboratory at Cork University
Hospital one day after collection, as documented on the paper request card, and was promptly centrifuged. Analysis was delayed for three days
due to operational constraints and serum indices were run at the same time as the biochemical analyses. Results showed a moderately haemolysed
specimen with remarkably low concentrations of both sodium (119 mmol/L) and total calcium (1.15 mmol/L), with all other parameters within their
appropriate reference intervals (RIs). The complete report was released electronically and both sodium and calcium results were phoned to, and
acknowledged by, the requesting general practitioner (GP). Discussion between the medical scientists and clinical biochemist on duty raised the
possibility that the specimen was significantly older than initially thought. Further discussion of results with the GP clarified that the documented
time of collection corresponded with specimen receipt by the courier, rather than the time of phlebotomy. Thus, the specimen was 7 days old when
received in the laboratory and 10 days old when analysed. This case illustrates the dangers of multiple convergent preanalytical errors. Laboratories
should be mindful of the stability of analytes in unseparated blood and unusual patterns of results which might suggest a specimen is “old”, and
that this may coexist with erroneous request information. Any potential adverse effects on patient care were prevented in this case by laboratory
vigilance
Evaluating the catching performance of aerodynamic rain gauges through field comparisons and CFD modelling
Metabolic profiles identify circulating biomarkers associated with heart failure in young single ventricle patients
Background: Children and young adults with single ventricle (SV) heart disease frequently develop heart failure (HF) that is intractable and difficult to treat. Our understanding of the molecular and biochemical reasons underlying this is imperfect. Thus, there is an urgent need for biomarkers that predict outcome and provide a rational basis for treatment, and advance our understanding of the basis of HF.
Objective: We sought to determine if a metabolomic approach would provide biochemical signatures of HF in SV children and young adults. If significant, these analytes might serve as biomarkers to predict outcome and inform on the biological mechanism(s) of HF.
Methods: We applied a multi-platform metabolomics approach composed of mass spectrometry (MS) and nuclear magnetic resonance (NMR) which yielded 495 and 26 metabolite measurements respectively. The plasma samples came from a cross-sectional set of young SV subjects, ages 2-19 years with ten control (Con) subjects and 16 SV subjects. Of the SV subjects, nine were diagnosed as congestive HF (SVHF), and 7 were not in HF. Metabolomic data were correlated with clinical status to determine if there was a signature associated with HF.
Results: There were no differences in age, height, weight or sex between the 3 cohorts. However, statistical analysis of the metabolomic profiles using ANOVA revealed 44 metabolites with significant differences between cohorts including 41 profiled by MS and 3 by NMR. These metabolites included acylcarnitines, amino acids, and bile acids, which distinguished Con from all SV subjects. Furthermore, metabolite profiles could distinguish between SV and SVHF subjects.
Conclusion: These are the first data to demonstrate a clear metabolomic signature associated with HF in children and young adults with SV. Larger studies are warranted to determine if these findings are predictive of progression to HF in time to provide intervention
Facilitating treatment engagement for early psychosis through peer-delivered decision support : Intervention development and protocol for pilot evaluation
Background: Emerging adults with early psychosis demonstrate high rates of service disengagement from critical early intervention services. Decision support interventions and peer support have both been shown to enhance service engagement but are understudied in this population. The purposes of this article are to describe the development of a novel peer-delivered decision coaching intervention for this population and to report plans for a pilot study designed to gather preliminary data about its feasibility, acceptability, and potential impact.
Methods: The intervention was developed based on formative qualitative data and in collaboration with a diverse team of researchers, key stakeholders, and expert consultants. The pilot trial will utilize a single-group (N = 20), pre-post, convergent mixed-methods design to explore whether and how the intervention addresses decision-making needs (the primary intervention target). The impact of the intervention on secondary outcomes (e.g., engagement in the program) will also be assessed. Additionally, through observation and feedback from the peer decision coach and study participants, we will evaluate the feasibility of research and intervention procedures, and the acceptability of information and support from the peer decision coach.
Discussion: The peer-delivered decision coaching intervention holds promise for assisting young people with making informed and values-consistent decisions about their care, and potentially enhancing service engagement within this traditionally difficult-to-engage population. If the intervention demonstrates feasibility and acceptability, and pilot data show its potential for improving treatment decision-making, our work will also lay the foundation for a new evidence base regarding roles for peer specialists on early intervention teams
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