140 research outputs found
The Technicolor Higgs in the Light of LHC Data
We consider scenarios in which the 125 GeV resonance observed at the Large
Hadron Collider is a Technicolor (TC) isosinglet scalar, the TC Higgs. By
comparison with quantum chromodynamics, we argue that the couplings of the TC
Higgs to the massive weak bosons are very close to the Standard Model (SM)
values. The couplings to photons and gluons are model-dependent, but close to
the SM values in several TC theories. The couplings of the TC Higgs to SM
fermions are due to interactions beyond TC, such as Extended Technicolor: if
such interactions successfully generate mass for the SM fermions, we argue that
the couplings of the latter to the TC Higgs are also SM-like.
We suggest a generic parameterization of the TC Higgs interactions with SM
particles that accommodates a large class of TC models, and we perform a fit of
these parameters to the Higgs LHC data. The fit reveals regions of parameter
space where the form factors are of order unity and consistent with data at the
95% CL, in agreement with expectations in TC theories. This indicates that the
discovered Higgs boson is consistent with the TC Higgs hypothesis for several
TC theories.Comment: 26 pages, 8 figure
Understanding the Role of Social Media in Incident/Crisis Communication
How organisations communicate with their audience during an incident or crisis is important because it can adversely affect corporate reputation if mishandled. With the advent of social media, organisations have only a few âgolden minutesâ rather than âgolden hoursâ to communicate with their audience as an incident/crisis unfolds. However, while social media usage by the general population is increasing rapidly, most organisations are not ready to manage incidents or crises via the use of social media. Theoretical knowledge is still lacking in this regard. This study provides a conceptual framework for investigating how organisations communicate with their audience via social media during an incident or crisis and aims to identify the important factors relating to the use of social media in a negative situation
Evaluation of a novel research trap for surveys of blue swimmer crab populations
Surveying free-ranging crab populations is important for monitoring the health of exploited stocks and predicting future productivity. Here, we present a novel research trap design for use in fisheries-independent surveys of blue swimmer crab (Portunus armatus) populations, and evaluate the trap against some existing approaches within an independent survey framework. Specifically, the trap design aimed to improve efficiency for capturing smaller crabs, without adversely affecting catches of larger crabs. We quantify and report the abundance and selectivity of these traps, relative to co-located samples obtained using beam trawls and standard commercial round traps, to establish whether these small-mesh traps may offer any improvements over existing survey methods. Comparison and evaluation of these small-mesh traps against other existing survey gear, in different places and at different times, showed that the traps are more effective at catching smaller crabs when they are present, and equally or more effective at catching larger size classes of crabs. The beam trawl appeared to be effective at capturing a reasonable size range of crabs; however, the number of crabs caught (using a similar investment of time) was substantially lower than that caught in traps. This novel small-mesh research trap appears suitable for fisheries-independent surveys of portunid crab species
Lobate Lac Scale (Paratachardina pseudolobata Kondo and Gullan) Invades from Oahu into Neighbor Islands: Statewide Survey in Hawaii
In Hawaii, lobate lac scale was rst detected on weeping banyan on Oahu in 2012. Since then, we have con rmed that lobate lac scale infests over 110 plant species in Hawaii, mainly ornamental and landscape plants in urban areas. The major impacts on host plants are dieback of twigs and branches, thinning of foliage, and death of the entire plant in some species. Given the frequency of in- terisland transportation of goods and people, it is likely that lobate lac scale spread to neighbor islands since its discovery on Oahu. We started this survey in January 2016 covering all major neighbor islands in Hawaii: Hawaii, Maui, Kauai, Molokai, and Lanai. Lobate lac scale was detected in Kona in May 2016, the rst con rmed incidence of this pest on a neighbor island outside of Oahu. Lobate lac scale was detected in Lihue in January 2017, the rst con rmed incidence of this pest on Kauai. With contribution from Hawaii Department of Agriculture, lobate lac scale was detected on Maui in May 2016. No lobate lac scale was detected on Molokai and Lanai in our survey. Inter-island shipping of nursery plants was considered the key route for the spread of lobate lac scale from Oahu to neighbor islands
Primary Eye Care in Eastern Nepal.
Purpose: Vision 2020 and the Global Action Plan 2013-2019 prioritise primary eye care (PEC) as an important component of reducing avoidable blindness. Studies in sub-Saharan Africa have demonstrated that current PEC provision is poor. There has been no evaluation of the current practice of PEC among primary health care workers (PHCWs) in Nepal.Methods: A mixed methods descriptive cross-sectional study with semi-structured interviews and focus group discussions (FGDs) was carried out in Eastern Nepal. Government employed PHCWs working at health posts in three districts were invited to take part in a PEC knowledge and skills assessment. Each health post was assessed for ophthalmic equipment and medications. Three focus group discussions and eight semi-structured interviews were carried out with community ophthalmic assistants, PHCWs and a district health manager.Results: 107 PHCWs in 35 health posts took part in the quantitative study. Only 8.4% had received eye care training. 27.1% PHCWs could diagnose a corneal ulcer, 83.2% conjunctivitis, 75.7% cataract and 54.2% ophthalmia neonatorum. Only 14.0% could measure visual acuity, and 5.7% of HPs had a vision chart. Ophthalmic assistants described their concern for the low level of PEC at health posts. PHCWs were keen to receive training and highlighted the need for greater government support in the provision of eye care services.Conclusion: PEC knowledge and skills among PHCWs in eastern Nepal is inadequate to provide quality PEC services. There is a pressing need for PEC training in the region, provision of ophthalmic equipment and greater government support for eye care
Magnetic Texture in Insulating Single Crystal High Entropy Oxide Spinel Films
Magnetic insulators are important materials for a range of next generation
memory and spintronic applications. Structural constraints in this class of
devices generally require a clean heterointerface that allows effective
magnetic coupling between the insulating layer and the conducting layer.
However, there are relatively few examples of magnetic insulators which can be
synthesized with surface qualities that would allow these smooth interfaces and
precisely tuned interfacial magnetic exchange coupling which might be
applicable at room temperature. In this work, we demonstrate an example of how
the configurational complexity in the magnetic insulator layer can be used to
realize these properties. The entropy-assisted synthesis is used to create
single crystal (Mg0.2Ni0.2Fe0.2Co0.2Cu0.2)Fe2O4 films on substrates spanning a
range of strain states. These films show smooth surfaces, high resistivity, and
strong magnetic responses at room temperature. Local and global magnetic
measurements further demonstrate how strain can be used to manipulate magnetic
texture and anisotropy. These findings provide insight into how precise
magnetic responses can be designed using compositionally complex materials that
may find application in next generation magnetic devices
Topical chlorhexidine 0.2% versus topical natamycin 5% for fungal keratitis in Nepal: rationale and design of a randomised controlled non-inferiority trial.
INTRODUCTION: Fungal infections of the cornea, fungal keratitis (FK), are challenging to treat. Current topical antifungals are not always effective and are often unavailable, particularly in low-income and middle-income countries where most cases occur. Topical natamycin 5% is usually first-line treatment, however, even when treated intensively, infections may progress to perforation of the eye in around a quarter of cases. Alternative antifungal medications are needed to treat this blinding disease.Chlorhexidine is an antiseptic agent with antibacterial and antifungal properties. Previous pilot studies suggest that topical chlorhexidine 0.2% compares favourably with topical natamycin. Full-scale randomised controlled trials (RCTs) of topical chlorhexidine 0.2% are warranted to answer this question definitively. METHODS AND ANALYSIS: We will test the hypothesis that topical chlorhexidine 0.2% is non-inferior to topical natamycin 5% in a two-arm, single-masked RCT. Participants are adults with FK presenting to a tertiary ophthalmic hospital in Nepal. Baseline assessment includes history, examination, photography, in vivo confocal microscopy and cornea scrapes for microbiology. Participants will be randomised to alternative topical antifungal treatments (topical chlorhexidine 0.2% and topical natamycin 5%; 1:1 ratio, 2-6 random block size). Patients are reviewed at day 2, day 7 (with reculture), day 14, day 21, month 2 and month 3. The primary outcome is the best spectacle corrected visual acuity (BSCVA) at 3âmonths. Primary analysis (intention to treat) will be by linear regression, with treatment arm and baseline BSCVA prespecified covariates. Secondary outcomes include epithelial healing time, scar/infiltrate size, ulcer depth, hypopyon size, perforation and/or therapeutic penetrating keratoplasty (corneal transplant), positive reculture rate (day 7) and quality of life (EuroQol-5 dimensions, WHO/PBD-VF20, WHOQOL-BREF). ETHICS AND DISSEMINATION: The Nepal Health Research Council, the Nepal Department of Drug Administration and the London School of Hygiene and Tropical Medicine ethics committee have approved the trial. The results will be presented at local and international meetings and submitted to peer-reviewed journals for publication. TRIAL REGISTRATION NUMBER: ISRCTN14332621; pre-results
Transfer of knowledge from model organisms to evolutionarily distant non-model organisms: The coral Pocillopora damicornis membrane signaling receptome
With the ease of gene sequencing and the technology available to study and manipulate non-model organisms, the extension of the methodological toolbox required to translate our understanding of model organisms to non-model organisms has become an urgent problem. For example, mining of large coral and their symbiont sequence data is a challenge, but also provides an opportunity for understanding functionality and evolution of these and other non-model organisms. Much more information than for any other eukaryotic species is available for humans, especially related to signal transduction and diseases. However, the coral cnidarian host and human have diverged over 700 million years ago and homologies between proteins in the two species are therefore often in the gray zone, or at least often undetectable with traditional BLAST searches. We introduce a two-stage approach to identifying putative coral homologues of human proteins. First, through remote homology detection using Hidden Markov Models, we identify candidate human homologues in the cnidarian genome. However, for many proteins, the human genome alone contains multiple family members with similar or even more divergence in sequence. In the second stage, therefore, we filter the remote homology results based on the functional and structural plausibility of each coral candidate, shortlisting the coral proteins likely to have conserved some of the functions of the human proteins. We demonstrate our approach with a pipeline for mapping membrane receptors in humans to membrane receptors in corals, with specific focus on the stony coral, P. damicornis. More than 1000 human membrane receptors mapped to 335 coral receptors, including 151 G protein coupled receptors (GPCRs). To validate specific sub-families, we chose opsin proteins, representative GPCRs that confer light sensitivity, and Toll-like receptors, representative non-GPCRs, which function in the immune response, and their ability to communicate with microorganisms. Through detailed structure-function analysis of their ligand-binding pockets and downstream signaling cascades, we selected those candidate remote homologues likely to carry out related functions in the corals. This pipeline may prove generally useful for other non-model organisms, such as to support the growing field of synthetic biology
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Agent orange exposure and prostate cancer risk in the million veteran program
BackgroundThe US government considers veterans to have been exposed to Agent Orange if they served in Vietnam while the carcinogen was in use, and these veterans are often deemed at high risk of prostate cancer (PCa). Here, we assess whether presumed Agent Orange exposure is independently associated with increased risk of any metastatic or fatal PCa in a diverse Veteran cohort still alive in the modern era (at least 2011), when accounting for race/ethnicity, family history, and genetic risk.Patients and methodsParticipants in the Million Veteran Program (MVP; enrollment began in 2011) who were on active duty during the Vietnam War era (August 1964-April 1975) were included (n = 301,470). Agent Orange exposure was determined using the US government definition. Genetic risk was assessed via a validated polygenic hazard score. Associations with age at diagnosis of any PCa, metastatic PCa, and death from PCa were assessed via Cox proportional hazards models.Results and interpretationOn univariable analysis, exposure to Agent Orange was not associated with increased PCa (hazard ratio [HR]: 1.02, 95% confidence interval [CI]: 1.00-1.04, p = 0.06), metastatic PCa (HR: 0.98, 95% CI: 0.91-1.05, p = 0.55), or fatal PCa (HR: 0.94, 95% CI: 0.79-1.09, p = 0.41). When accounting for race/ethnicity and family history, Agent Orange exposure was independently associated with slightly increased risk of PCa (HR: 1.06, 95% CI: 1.04-1.09, <10-6) but not with metastatic PCa (HR: 1.07, 95% CI: 0.98-1.15, p = 0.10) or PCa death (HR: 1.02, 95% CI: 0.83-1.23, p = 0.09). Similar results were found when accounting for genetic risk. Agent Orange exposure history may not improve modern PCa risk stratification
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