3,265 research outputs found
Palladium(II)-Catalysed Aminocarbonylation of Terminal Alkynes for the Synthesis of 2-Ynamides: Addressing the Challenges of Solvents and Gas Mixtures
2âYnamides can be synthesised through Pd(II) catalysed oxidative carbonylation, utilising low catalyst loadings. A variety of alkynes and amines can be used to afford 2âynamides in high yields, whilst overcoming the drawbacks associated with previous oxidative methods, which rely on dangerous solvents and gas mixtures. The use of [NBu(4)]I allows the utilisation of the industrially recommended solvent ethyl acetate. O(2) can be used as the terminal oxidant, and the catalyst can operate under safer conditions with low O(2) concentrations
Exploring the limits of the self consistent Born approximation for inelastic electronic transport
The non equilibrium Green function formalism is today the standard
computational method for describing elastic transport in molecular devices.
This can be extended to include inelastic scattering by the so called
self-consistent Born approximation (SCBA), where the interaction of the
electrons with the vibrations of the molecule is assumed to be weak and it is
treated perturbatively. The validity of such an assumption and therefore of the
SCBA is difficult to establish with certainty. In this work we explore the
limitations of the SCBA by using a simple tight-binding model with the
electron-phonon coupling strength chosen as a free parameter. As
model devices we consider Au mono-atomic chains and a molecule
sandwiched between Pt electrodes. In both cases our self-consistent
calculations demonstrate a breakdown of the SCBA for large and we
identify a weak and strong coupling regime. For weak coupling our SCBA results
compare closely with those obtained with exact scattering theory. However in
the strong coupling regime large deviations are found. In particular we
demonstrate that there is a critical coupling strength, characteristic of the
materials system, beyond which multiple self-consistent solutions can be found
depending on the initial conditions in the simulation. We attribute these
features to the breakdown of the perturbative expansion leading to the SCBA.Comment: 12 pages, 16 figures, 1 Tabl
Chiral Symmetry and light resonances in hot and dense matter
We present a study of the scattering amplitude in the and
channels at finite temperature and nuclear density within a chiral
unitary framework. Meson resonances are dynamically generated in our approach,
which allows us to analyze the behavior of their associated scattering poles
when the system is driven towards chiral symmetry restoration. Medium effects
are incorporated in three ways: (a) by thermal corrections of the unitarized
scattering amplitudes, (b) by finite nuclear density effects associated to a
renormalization of the pion decay constant, and complementarily (c) by
extending our calculation of the scalar-isoscalar channel to account for finite
nuclear density and temperature effects in a microscopic many-body
implementation of pion dynamics. Our results are discussed in connection with
several phenomenological aspects relevant for nuclear matter and Heavy-Ion
Collision experiments, such as mass scaling vs broadening from dilepton
spectra and chiral restoration signals in the channel. We also
elaborate on the molecular nature of resonances.Comment: 14 pages, 14 figures. Contribution to Hard Probes 2008, Illa de A
Toxa, Spain, June 8th-14th 200
Biocatalytic and Chemo-Enzymatic Synthesis of Quinolines and 2-Quinolones by Monoamine Oxidase (MAO-N) and Horseradish Peroxidase (HRP) Biocatalysts
The oxidative aromatization of aliphatic N-heterocycles is a fundamental organic transformation for the preparation of a diverse array of heteroaromatic compounds. Despite many attempts to improve the efficiency and practicality of this transformation, most synthetic methodologies still require toxic and expensive reagents as well as harsh conditions. Herein, we describe two enzymatic strategies for the oxidation of 1,2,3,4-tetrahydroquinolines (THQs) and N-cyclopropyl-N-alkylanilines into quinolines and 2-quinolones, respectively. Whole cells and purified monoamine oxidase (MAO-N) enzymes were used to effectively catalyze the biotransformation of THQs into the corresponding aromatic quinoline derivatives, while N-cyclopropyl-N-alkylanilines were converted into 2-quinolone compounds through a horseradish peroxidase (HRP)-catalyzed annulation/aromatization reaction followed by Fe-mediated oxidation
Development and validation of a PROM to capture holistic outcomes in traditional, complementary and integrative medicine - The Warwick Holistic Health Questionnaire (WHHQ-18)
Introduction: Existing patient reported outcome measures (PROMs) do not capture all holistic outcomes observed in Traditional, Complementary and Integrative Medicine (TCIM). This study reports development and validation of a PROM to support research on craniosacral therapy (CST) and other TCIMs.
Methods: Using a conceptual framework and items developed and evaluated with clients and practitioners in a CST setting, a questionnaire was developed and tested using mixed methods approaches. Evaluation included an iterative process. Psychometric tests: structural validity (exploratory factor analysis, EFA), internal consistency (Cronbach's alpha), convergent validity (correlations with Warwick-Edinburgh Mental Wellbeing Scale, Short Form-12v2 (SF-12), Harry Edwards Healing Impact Questionnaire), repeatability and responsiveness (t-tests; intra class coefficients, ICC).
Results: The Warwick Holistic Health Questionnaire (WHHQ-18) was resolved covering mental, physical, emotional and spiritual wellbeing, self-awareness, engaging in life, responsibility for self, living in the moment and satisfaction with life.
EFA revealed four correlated sub-scales. Internal reliability was good (alpha = 0.852). Convergent validity showed strong positive correlation with other wellbeing measures, but no correlation with health-related quality of life (SF-12). Repeatability testing showed good agreement (ICC=0.822) and no differences in scores for test-retest (paired t-test: t = 0.355, p = 0.723). Responsiveness analysis showed significant differences in scores (paired t-test t = 6.15, p < 0.001) with 46% of participants having an effect size of 0.5 or more.
Conclusion: WHHQ-18 is the first PROM developed for CST practice and captures outcomes important to TCIM more broadly. Good internal consistency, test-retest reliability and responsive at individual and group level make this new PROM an attractive resource for evaluators. Lack of convergent validity with SF-12 scales suggests WHHQ-18 be added to rather than replace HRQol measures in clinical studies
Galaxy and mass assembly (GAMA) : The wavelength-dependent sizes and profiles of galaxies revealed by MegaMorph
We investigate the relationship between colour and structure within galaxies using a large, volume-limited sample of bright, low-redshift galaxies with optical-near-infrared imaging from the Galaxy AndMass Assembly survey.We fit single-component,wavelength-dependent, elliptical SĂ©rsic models to all passbands simultaneously, using software developed by the MegaMorph project. Dividing our sample by n and colour, the recovered wavelength variations in effective radius (Re) and SĂ©rsic index (n) reveal the internal structure, and hence formation history, of different types of galaxies. All these trends depend on n; some have an additional dependence on galaxy colour. Late-type galaxies (nr 2.5), even though they maintain constant n with wavelength, revealing that ellipticals are a superimposition of different stellar populations associated with multiple collapse and merging events. Processes leading to structures with larger Re must be associated with lower metallicity or younger stellar populations. This appears to rule out the formation of young cores through dissipative gas accretion as an important mechanism in the recent lives of luminous elliptical galaxies.Peer reviewe
East Midlands Research into Ageing Network (EMRAN) Discussion Paper Series
Academic geriatric medicine in Leicester
.
There has never been a better time to consider joining us. We have recently appointed a
Professor in Geriatric Medicine, alongside Tom Robinson in stroke and Victoria Haunton,
who has just joined as a Senior Lecturer in Geriatric Medicine. We have fantastic
opportunities to support students in their academic pursuits through a well-established
intercalated BSc programme, and routes on through such as ACF posts, and a successful
track-record in delivering higher degrees leading to ACL post. We collaborate strongly
with Health Sciences, including academic primary care. See below for more detail on our
existing academic set-up.
Leicester Academy for the Study of Ageing
We are also collaborating on a grander scale, through a joint academic venture focusing
on ageing, the âLeicester Academy for the Study of Ageingâ (LASA), which involves the
local health service providers (acute and community), De Montfort University; University
of Leicester; Leicester City Council; Leicestershire County Council and Leicester Age UK.
Professors Jayne Brown and Simon Conroy jointly Chair LASA and have recently been
joined by two further Chairs, Professors Kay de Vries and Bertha Ochieng. Karen
Harrison Dening has also recently been appointed an Honorary Chair.
LASA aims to improve outcomes for older people and those that care for them that takes
a person-centred, whole system perspective. Our research will take a global perspective,
but will seek to maximise benefits for the people of Leicester, Leicestershire and Rutland,
including building capacity. We are undertaking applied, translational, interdisciplinary
research, focused on older people, which will deliver research outcomes that address
domains from: physical/medical; functional ability, cognitive/psychological; social or
environmental factors. LASA also seeks to support commissioners and providers alike for
advice on how to improve care for older people, whether by research, education or
service delivery. Examples of recent research projects include: âLocal History CafĂ©â
project specifically undertaking an evaluation on loneliness and social isolation; âBetter
Visitsâ project focused on improving visiting for family members of people with dementia
resident in care homes; and a study on health issues for older LGBT people in Leicester.
Clinical Geriatric Medicine in Leicester
We have developed a service which recognises the complexity of managing frail older
people at the interface (acute care, emergency care and links with community services).
There are presently 17 consultant geriatricians supported by existing multidisciplinary
teams, including the largest complement of Advance Nurse Practitioners in the country.
Together we deliver Comprehensive Geriatric Assessment to frail older people with
urgent care needs in acute and community settings.
The acute and emergency frailty units â Leicester Royal Infirmary
This development aims at delivering Comprehensive Geriatric Assessment to frail older
people in the acute setting. Patients are screened for frailty in the Emergency
Department and then undergo a multidisciplinary assessment including a consultant
geriatrician, before being triaged to the most appropriate setting. This might include
admission to in-patient care in the acute or community setting, intermediate care
(residential or home based), or occasionally other specialist care (e.g. cardiorespiratory).
Our new emergency department is the countyâs first frail friendly build and includes
fantastic facilities aimed at promoting early recovering and reducing the risk of hospital
associated harms.
There is also a daily liaison service jointly run with the psychogeriatricians (FOPAL); we
have been examining geriatric outreach to oncology and surgery as part of an NIHR
funded study.
We are home to the Acute Frailty Network, and those interested in service developments
at the national scale would be welcome to get involved.
Orthogeriatrics
There are now dedicated hip fracture wards and joint care with anaesthetists,
orthopaedic surgeons and geriatricians. There are also consultants in metabolic bone
disease that run clinics.
Community work
Community work will consist of reviewing patients in clinic who have been triaged to
return to the community setting following an acute assessment described above.
Additionally, primary care colleagues refer to outpatients for sub-acute reviews. You will
work closely with local GPs with support from consultants to deliver post-acute, subacute,
intermediate and rehabilitation care services.
Stroke Medicine
24/7 thrombolysis and TIA services. The latter is considered one of the best in the UK
and along with the high standard of vascular surgery locally means one of the best
performances regarding carotid intervention
Recommended from our members
Reflecting back, looking forward: the challenges for location-based learning
This final section of the report has been reproduced from âD3.1 The STELLAR Rendez-Vous I report and white papersâ, published in 2009 by the STELLAR Network of Excellence. It is included here for completeness; we, as co-authors, felt that it was important to look back at the main contributions to theworkshop and also where the challenges lie for the future.
This chapter addresses two critical questions:
- What has been learned from this workshop, especially in respect to the STELLAR Grand Challenges (âConnecting learnersâ, âOrchestrationâ and âContextualisationâ)?
- What are the new research questions and issues for location-based learning, with respect to the Grand Challenges (âConnecting learnersâ, âOrchestrationâand âContextualisationâ)
- âŠ