11,185 research outputs found
Identification of drug resistance mutations in HIV from constraints on natural evolution
Human immunodeficiency virus (HIV) evolves with extraordinary rapidity.
However, its evolution is constrained by interactions between mutations in its
fitness landscape. Here we show that an Ising model describing these
interactions, inferred from sequence data obtained prior to the use of
antiretroviral drugs, can be used to identify clinically significant sites of
resistance mutations. Successful predictions of the resistance sites indicate
progress in the development of successful models of real viral evolution at the
single residue level, and suggest that our approach may be applied to help
design new therapies that are less prone to failure even where resistance data
is not yet available.Comment: 5 pages, 3 figure
Buffet test in the National Transonic Facility
A buffet test of a commercial transport model was accomplished in the National Transonic Facility at the NASA Langley Research Center. This aeroelastic test was unprecedented for this wind tunnel and posed a high risk for the facility. Presented here are the test results from a structural dynamics and aeroelastic response point of view. The activities required for the safety analysis and risk assessment are described. The test was conducted in the same manner as a flutter test and employed on-board dynamic instrumentation, real time dynamic data monitoring, and automatic and manual tunnel interlock systems for protecting the model
Long-lived heteronuclear spin-singlet states
We report observation of long-lived spin-singlet states in a 13C-1H spin pair
at zero magnetic field. In 13C-labeled formic acid, we observe spin-singlet
lifetimes as long as 37 seconds, about a factor of three longer than the T1
lifetime of dipole polarization in the triplet state. We also observe that the
lifetime of the singlet-triplet coherence, T2, is longer than T1. Moreover, we
demonstrate that this singlet states formed by spins of a heteronucleus and a
1H nucleus, can exhibit longer lifetimes than the respective triplet states in
systems consisting of more than two nuclear spins. Although long-lived
homonuclear spin-singlet states have been extensively studied, this is the
first experimental observation of analogous spin-singlets consisting of a
heteronucleus and a proton.Comment: 5 pages, 4 figure
Love, rights and solidarity: studying children's participation using Honneth's theory of recognition
Recent attempts to theorize childrenâs participation have drawn on a wide range of ideas, concepts and models from political and social theory. The aim of this article is to explore the specific usefulness of Honnethâs theory of a âstruggle for recognitionâ in thinking about this area of practice. The article identifies what is distinctive about Honnethâs theory of recognition, and how it differs from other theories of recognition. It then considers the relevance of Honnethâs conceptual framework to the social position of children, including those who may be involved in a variety of âparticipatoryâ activities.
It looks at how useful Honnethâs ideas are in direct engagement with young peopleâs praxis, drawing on ethnographic research with members of a children and young peopleâs forum. The article concludes by reflecting on the implications of this theoretical approach and the further questions which it opens up for theories of participation and of adultâchild relations more generally
Optimum nutritional strategies for cardiovascular disease prevention and rehabilitation (BACPR)
Nutrition has a central role in both primary and secondary prevention of cardiovascular disease (CVD) yet only relatively recently has food been regarded as a treatment, rather than as an adjunct to established medical and pharmacotherapy. As a field of research, nutrition science is constantly evolving making it difficult for patients and practitioners to ascertain best practice. This is compounded further by the inherent difficulties in performing double-blind randomised controlled trials.
This paper covers dietary patterns that are associated with improved cardiovascular outcomes, including the Mediterranean Diet but also low-carbohydrate diets and the potential issues encountered with their implementation. We suggest there must be a refocus away from macronutrients and consideration of whole foods when advising individuals. This approach is fundamental to practice, as clinical guidelines have focussed on macronutrients without necessarily considering their source, and ultimately people consume foods containing multiple nutrients. The inclusion of food-based recommendations aids the practitioner to help the patient make genuine and meaningful changes in their diet. We advocate that the cardioprotective diet constructed around the traditional Mediterranean eating pattern (based around vegetables and fruits, nuts, legumes, and unrefined cereals, with modest amounts of fish and shellfish, and fermented dairy products) is still important. However there are other approaches that can be tried, including low-carbohydrate diets. We encourage practitioners to adopt a flexible dietary approach, being mindful of patient preferences and other comorbidities that may necessitate deviations away from established advice, and advocate for more dietitians in this field to guide the multi-professional team
Solar-like oscillations in the G2 subgiant beta Hydri from dual-site observations
We have observed oscillations in the nearby G2 subgiant star beta Hyi using
high-precision velocity observations obtained over more than a week with the
HARPS and UCLES spectrographs. The oscillation frequencies show a regular comb
structure, as expected for solar-like oscillations, but with several l=1 modes
being strongly affected by avoided crossings. The data, combined with those we
obtained five years earlier, allow us to identify 28 oscillation modes. By
scaling the large frequency separation from the Sun, we measure the mean
density of beta Hyi to an accuracy of 0.6%. The amplitudes of the oscillations
are about 2.5 times solar and the mode lifetime is 2.3 d. A detailed comparison
of the mixed l=1 modes with theoretical models should allow a precise estimate
of the age of the star.Comment: 13 pages, 14 figures, accepted by ApJ. Fixed minor typo (ref to Fig
14
Co-producing research with academics and industry to create a more resilient UK water sector
This is the final version. Available on open access from UCL Press via the DOI in this recordSocietal, economic and environmental impact generated by academic research is a key focus of publicly funded research in the UK. Drawing on experiences from the Safe & SuRe project, a five-year research project that was co-produced with industry, this paper explores the challenges, learnings and benefits of co-producing research with academics and practitioners to create a more resilient UK water sector. Three aspects of the project are explored in detail: the use of a steering group, co-developing research intensively with a water company, and co-dissemination industry-facing events. Emerging themes include: (1) benefits of the industry steering group to develop working relationships and trust among the group; (2) increased dialogue and sharing of information between industry and academics going beyond the one-way communication more commonly reported by STEM academics; and (3) the value of co-disseminating research to maintain and engage new connections and spark new research questions.Engineering and Physical Sciences Research Council (EPSRC
Chiral Corrections to Lattice Calculations of Charge Radii
Logarithmic divergences in pion and proton charge radii associated with
chiral loops are investigated to assess systematic uncertainties in current
lattice determinations of charge radii. The chiral corrections offer a possible
solution to the long standing problem of why present lattice calculations yield
proton and pion radii which are similar in size.Comment: PostScript file only. Ten pages. Figures included. U. of MD Preprint
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