681 research outputs found
Winter Predation of Mustela Erminea in Northern Canada
Weasels are the most widely distributed mammalian predators in North America. This paper reports the results of a study of short-tail weasel predation in northern Alberta and the Northwest Territories during the winter of 1964-65. ..
The visual orbits of the spectroscopic binaries HD 6118 and HD 27483 from the Palomar Testbed Interferometer
We present optical interferometric observations of two double-lined
spectroscopic binaries, HD 6118 and HD 27483, taken with the Palomar Testbed
Interferometer (PTI) in the K band. HD 6118 is one of the most eccentric
spectroscopic binaries and HD 27483 a spectroscopic binary in the Hyades open
cluster. The data collected with PTI in 2001-2002 allow us to determine
astrometric orbits and when combined with the radial velocity measurements
derive all physical parameters of the systems. The masses of the components are
2.65 +/- 0.27 M_Sun and 2.36 +/- 0.24 M_Sun for HD 6118 and 1.38 +/- 0.13 M_Sun
and 1.39 +/- 0.13 M_Sun for HD 27483. The apparent semi-major axis of HD 27483
is only 1.2 mas making it the closest binary successfully observed with an
optical interferometer.Comment: submitted to Ap
Subgroup-specific structural variation across 1,000 medulloblastoma genomes
Abstract
Medulloblastoma, the most common malignant paediatric brain tumour, is currently treated with nonspecific cytotoxic therapies including surgery, whole-brain radiation, and aggressive chemotherapy. As medulloblastoma exhibits marked intertumoural heterogeneity, with at least four distinct molecular variants, previous attempts to identify targets for therapy have been underpowered because of small samples sizes. Here we report somatic copy number aberrations (SCNAs) in 1,087 unique medulloblastomas. SCNAs are common in medulloblastoma, and are predominantly subgroup-enriched. The most common region of focal copy number gain is a tandem duplication of SNCAIP, a gene associated with Parkinson's disease, which is exquisitely restricted to Group 4Ī±. Recurrent translocations of PVT1, including PVT1-MYC and PVT1-NDRG1, that arise through chromothripsis are restricted to Group 3. Numerous targetable SCNAs, including recurrent events targeting TGF-Ī² signalling in Group 3, and NF-ĪŗB signalling in Group 4, suggest future avenues for rational, targeted therapy
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Speech, language and communication needs and mental health: the experiences of speech and language therapists and mental health professionals
Background
While the relationship between speech, language and communication needs (SLCN) and mental health difficulties has been recognized, speech and language therapists (SLTs), and mental health professionals face challenges in assessing and treating children with these co-occurring needs. There exists a gap in the evidence base for best practice for professionals working with children and young people (CYP) who experience difficulties in both areas.
Aims
To explore the views of SLTs and mental health clinicians about their experiences of working with CYP exhibiting co-occurring SLCN and mental health difficulties.
Methods & Procedures
Semi-structured interviews were conducted with eight SLTs and six mental health professionals, including psychotherapists, clinical psychologists, play therapists and counsellors, with experience working with CYP with SLCN. Interviews were analysed using reflexive thematic analysis and themes were identified from the data.
Outcomes & Results
Participants felt that SLCN and mental health difficulties frequently co-occur. Participants described how CYP with SLCN and mental health issues commonly experience difficulties across and between the domains of language and cognition, emotional well-being and challenging behaviour. Findings suggest that there are organizational limitations in the fields of SLT and mental health that have implications for the efficacy of assessment and treatment of CYP with SLCN and mental health difficulties. Traditional talking therapies were perceived to be inaccessible and ineffective for CYP with SLCN and mental health difficulties. Interventions blending behaviour and emotion programmes with language and communication interventions were considered potentially beneficial.
Conclusions & Implications
Future research should explore and evaluate current services and service set-up in SLT and mental health. The findings from this study have important implications for the efficacy of treatments provided to this population suggesting that more research needs to be done into effective diagnosis and interventions for this population.
WHAT THIS PAPER ADDS
What is already known on the subject
Research suggests that CYP with SLCN, such as developmental language disorder (DLD), are likely to experience mental health difficulties including depression, anxiety and poor emotional well-being. CYP who experience difficulties with SLCN and poor mental health are not well understood and this area remains under-researched. This has implications for clinician knowledge and therefore the effective diagnosis and treatment of children and adolescents experiencing SLCN and mental health difficulties. In addition, little is known about the accessibility of talking therapies to CYP presenting with SLCN and mental health difficulties.
What this paper adds to existing knowledge
SLCN issues are understood by SLTs and mental health issues are understood by mental health professionals, but where these co-occur difficulties exist for the diagnostic process, with professionals perceiving that CYP in this category are often undiagnosed or misdiagnosed. Organizational boundaries between SLT and mental health were perceived to contribute to a lack of understanding of SLCN and mental health needs, which has implications for effective diagnosis and treatment. Traditional talking therapies were thought to be inaccessible for CYP with SLCN and mental health difficulties. Interventions used in both SLT and psychotherapy were perceived as clinically useful if combined.
What are the potential or actual clinical implications of this work?
This paper highlights implications for the accessibility and efficacy of the assessment and treatment provided to this population and to the organization of services currently treating this group of CYP. A direction for future research would be to undertake service evaluations and intervention-based studies
Rapid, reliable, and reproducible molecular sub-grouping of clinical medulloblastoma samples
The diagnosis of medulloblastoma likely encompasses several distinct entities, with recent evidence for the existence of at least four unique molecular subgroups that exhibit distinct genetic, transcriptional, demographic, and clinical features. Assignment of molecular subgroup through routine profiling of high-quality RNA on expression microarrays is likely impractical in the clinical setting. The planning and execution of medulloblastoma clinical trials that stratify by subgroup, or which are targeted to a specific subgroup requires technologies that can be economically, rapidly, reliably, and reproducibly applied to formalin-fixed paraffin embedded (FFPE) specimens. In the current study, we have developed an assay that accurately measures the expression level of 22 medulloblastoma subgroup-specific signature genes (CodeSet) using nanoString nCounter Technology. Comparison of the nanoString assay with Affymetrix expression array data on a training series of 101 medulloblastomas of known subgroup demonstrated a high concordance (Pearson correlation rĀ =Ā 0.86). The assay was validated on a second set of 130 non-overlapping medulloblastomas of known subgroup, correctly assigning 98% (127/130) of tumors to the appropriate subgroup. Reproducibility was demonstrated by repeating the assay in three independent laboratories in Canada, the United States, and Switzerland. Finally, the nanoString assay could confidently predict subgroup in 88% of recent FFPE cases, of which 100% had accurate subgroup assignment. We present an assay based on nanoString technology that is capable of rapidly, reliably, and reproducibly assigning clinical FFPE medulloblastoma samples to their molecular subgroup, and which is highly suited for future medulloblastoma clinical trials
Deterministically Computing Reduction Numbers of Polynomial Ideals
We discuss the problem of determining reduction number of a polynomial ideal
I in n variables. We present two algorithms based on parametric computations.
The first one determines the absolute reduction number of I and requires
computation in a polynomial ring with (n-dim(I))dim(I) parameters and n-dim(I)
variables. The second one computes via a Grobner system the set of all
reduction numbers of the ideal I and thus in particular also its big reduction
number. However,it requires computations in a ring with n.dim(I) parameters and
n variables.Comment: This new version replaces the earlier version arXiv:1404.1721 and it
has been accepted for publication in the proceedings of CASC 2014, Warsaw,
Polna
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 āLeicester Academy for the Study of Ageingā (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: āLocal History CafĆ©ā
project specifically undertaking an evaluation on loneliness and social isolation; āBetter
Visitsā 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 ā 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 countyās 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
Molecular subgroups of medulloblastoma: the current consensus
Medulloblastoma, a small blue cell malignancy of the cerebellum, is a major cause of morbidity and mortality in pediatric oncology. Current mechanisms for clinical prognostication and stratification include clinical factors (age, presence of metastases, and extent of resection) as well as histological subgrouping (classic, desmoplastic, and large cell/anaplastic histology). Transcriptional profiling studies of medulloblastoma cohorts from several research groups around the globe have suggested the existence of multiple distinct molecular subgroups that differ in their demographics, transcriptomes, somatic genetic events, and clinical outcomes. Variations in the number, composition, and nature of the subgroups between studies brought about a consensus conference in Boston in the fall of 2010. Discussants at the conference came to a consensus that the evidence supported the existence of four main subgroups of medulloblastoma (Wnt, Shh, Group 3, and Group 4). Participants outlined the demographic, transcriptional, genetic, and clinical differences between the four subgroups. While it is anticipated that the molecular classification of medulloblastoma will continue to evolve and diversify in the future as larger cohorts are studied at greater depth, herein we outline the current consensus nomenclature, and the differences between the medulloblastoma subgroups
On certain infinite extensions of the rationals with Northcott property
A set of algebraic numbers has the Northcott property if each of its subsets
of bounded Weil height is finite. Northcott's Theorem, which has many
Diophantine applications, states that sets of bounded degree have the Northcott
property. Bombieri, Dvornicich and Zannier raised the problem of finding fields
of infinite degree with this property. Bombieri and Zannier have shown that
\IQ_{ab}^{(d)}, the maximal abelian subfield of the field generated by all
algebraic numbers of degree at most , is such a field. In this note we give
a simple criterion for the Northcott property and, as an application, we deduce
several new examples, e.g.
\IQ(2^{1/d_1},3^{1/d_2},5^{1/d_3},7^{1/d_4},11^{1/d_5},...) has the Northcott
property if and only if
tends to infinity
TERT promoter mutation and aberrant hypermethylation are associated with elevated expression in medulloblastoma and characterise the majority of non-infant SHH subgroup tumours.
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