3,891 research outputs found
Issues of alcohol misuse among older people : attitudes and experiences of social work practitioners
This small-scale qualitative research focused on the experiences of social workers vis--vis older people who misuse alcohol. Based in an Older People's Team in the west of Scotland, the study explored service provision for alcohol misuse and examined whether practitioners felt the existing services provided by the Substance Misuse Team were effective in meeting the needs of older people with an alcohol problem. Using semi-structured interviews, data were collected from 18 participants, the majority (14) of whom were female and whose ages ranged from 31 to 54 years. Several key themes emerged including the extent of alcohol problems among older people and the complex reasons that cause older people to misuse alcohol. These reasons commonly related to the increasing challenges of old age. The data also demonstrated that current services are not meeting the needs of older people. Practitioners identified a need for an 'age-specific' approach to target more effectively the complex needs of older people. Recommendations from practitioners included ways to develop new and more effective services, including a more age-specific service, such as providing longer term support in older people's own homes, using a specialised support worker, and increasing staff training on alcohol use among older people
Long-Term Monitoring Of A High-Latitude Coral Reef System Off Southeast Florida, Usa: A Partnership Between Academia And Resource Management
Significant coral reef community development exists along the eastern shelf of the United States from the Dry Tortugas through the Florida Keys (Monroe County) and Southeast (SE) Florida (Miami-Dade, Broward, Palm Beach, and Martin Counties). State and county resource managers have partnered with academia to monitor the health of the SE Florida reef system. Since 2000, more than 20 sites have been monitored annually offshore Broward County. Quantitative data includes stony coral species cover, colony size, density, and condition (bleaching, disease, etc.) and gorgonian and sponge density. The SE Florida Coral Reef Evaluation and Monitoring Project (SECREMP) was established in 2003 as an expansion of the Florida Keys Coral Reef Evaluation and Monitoring Project (CREMP). Thirteen SECREMP sites are monitored annually across the 4 SE Florida counties. The stony coral, gorgonian, sponge, and other functional group cover data collected within the SECREMP sites and the Keys CREMP sites provides status and trend information for the entire Florida reef tract. The SE Florida reef system typically has 2-4% stony coral cover with more than 30 stony coral species and a diverse assemblage of octocoral, sponges, and fishes. Since their inception, monitoring efforts have shown relatively stable levels in stony coral cover and density. However, there have been many impacts to the SE Florida ecosystem resulting from its proximity to the highly developed and urbanized SE Florida coast. These reefs are influenced by many factors including commercial and recreational fishing and diving, major shipping ports, sewer outfalls, ship groundings, and coastal construction activities. SE Florida’s coral reef ecosystems generate $1.1 billion in annual income and support 36,000 jobs in the region. The uniqueness and value of these resources to the community demands sustained cooperative monitoring efforts and increased investigations into limiting environmental/ecological processes
Development of Biomarkers Based on Diet-Dependent Metabolic Serotypes: Concerns and Approaches for Cohort and Gender Issues in Serum Metabolome Studies
This is the publisher's version, also available electronically from: http://online.liebertpub.com/doi/pdfplus/10.1089/omi.2004.8.209Mathematical models that reflect the effects of dietary restriction (DR) on the sera
metabolome may have utility in understanding the mechanisms of DR and in applying this
knowledge to human epidemiological studies. Previous studies demonstrated both the feasibility
of identifying biomarkers through metabolome analysis and the validity of our approach
in independent cohorts of 6-month-oId male and female ad libitum fed or DR rats.
Cross-cohort studies showed that cohort-specific effects distorted the dataset The present
study extends these observations across the entire sample set, thereby validating our markers
independently of specific cohorts. Metabolites originally identified in males were examined
in females and vice-versa. DR's effect on the metabolom e is partially gender-specific
and is modulated by environmental factors. DR reduces inter-gender differences in the
metabolome. Univariate statistical methods showed that 56/93 metabolites in the female samples
and 39/93 metabolites in the male samples were significantly altered (using our previous
cut-off criteria of p ^ 0.2) by DR. The metabolites modulated by DR present a wide
spectrum of concentration, redox reactivity and hydrophilicity, suggesting that our serotype
is broadly representative of the metabolome and that DR has broad effects on the
metabolome. These studies, coupled with those in the preceding and following reports, also
highlight the utility for consideration of the metabolome as a network of metabolites using
appropriate data analysis approaches. The inter-cohort and inter-gender differences addressed
herein suggest potential cautions, and potential approaches, for identification of multivariate
biomarker profiles that reflect changes in physiological status, such as a metabolism
that predisposes to increased risk of neoplasia
Development of Biomarkers Based on Diet-Dependent Metabolic Serotypes: Practical Issues in Development of Expert System-Based Classification Models in Metabolomic Studies
This is the publisher's official version, also available electronically from: http://online.liebertpub.com/doi/pdfplus/10.1089/omi.2004.8.197Dietary restriction (DR)-induced changes in the serum metabolome may be biomarkers for
physiological status (e.g., relative risk of developing age-related diseases such as cancer).
Megavariate analysis (unsupervised hierarchical cluster analysis IHCAJ; principal components
analysis [PCAJ) of serum metabolites reproducibly distinguish DR from ad libitum fed
rats. Component-based approaches (i.e., PCA) consistently perform as well as or better than
distance-based metrics (i.e., HCA). We therefore tested the following: (A) Do identified subsets
of serum metabolites contain sufficient information to construct mathematical models
of class membership (i.e., expert systems)? (B) Do component-based metrics out-perform
distance-based metrics? Testing was conducted using KNN (k-nearest neighbors, supervised
HCA) and SIMCA (soft independent modeling of class analogy, supervised PCA). Models
were built with single cohorts, combined cohorts or mixed samples from previously studied
cohorts as training sets. Both algorithms over-fit models based on single cohort training sets.
KNN models had >85% accuracy within training/test sets, but were unstable (i.e., values of
k could not be accurately set in advance). SIMCA models had 100% accuracy within all
training sets, 89% accuracy in test sets, did not appear to over-fit mixed cohort training sets,
and did not require post-hoc modeling adjustments. These data indicate that (i) previously
defined metabolites are robust enough to construct classification models (expert systems)
with SIMCA that can predict unknowns by dietary category; (ii) component-based analyses
outperformed distance-based metrics; (iii) use of over-fitting controls is essential; and (iv)
subtle inter-cohort variability may be a critical issue for high data density biomarker studies
that lack state markers
Development of Biomarkers Based on Diet-Dependent Metabolic Serotypes: Characteristics of Component-Based Models of Metabolic Serotypes
This is the publisher's version, also available electronically from: http://online.liebertpub.com/doi/pdfplus/10.1089/omi.2004Our research seeks to identify a scrum profile, or serotype, that reflects the systemic physiologic
modifications resultant from dietary restriction (DR), in part such that this knowledge
can be applied for biomarker studies. Direct comparison suggests that component-based
classification algorithms consistently out-perform distance-based metrics for studies of nutritional
modulation of metabolic serotype, but are subject to over-fitting concerns. Intercohort
differences in the sera metabolome could partially obscure the effects of DR. Further
analysis now shows that implementation of component-based approaches (also called projection
methods) optimized for class separation and controlled for over-fitting have >97%
accuracy for distinguishing sera from control or DR rats. DR's effect on the metabolome is
shown to be robust across cohorts, but differs in males and females (although some metabolites
are affected in both). We demonstrate the utility of projection-based methods for both
sample and variable diagnostics, including identification of critical metabolites and samples
that are atypical with respect to both class and variable models. Inclusion of non-statistically
different variables enhances classification models. Variables that contribute to these
models are sharply dependent on mathematical processing techniques; some variables that
do not contribute under one paradigm arc powerful under alternative mathematical paradigms.
In practical terms, this information may find purpose in other endeavors, such as
mechanistic studies of DR. Application of these approaches confirms the utility of megavariate
data analysis techniques for optimal generation of biomarkers based on nutritional modulation
of physiological processes
A well-separated pairs decomposition algorithm for k-d trees implemented on multi-core architectures
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.Variations of k-d trees represent a fundamental data structure used in Computational Geometry with numerous applications in science. For example particle track tting in the software of the LHC experiments, and in simulations of N-body systems in the study of dynamics of interacting galaxies, particle beam physics, and molecular dynamics in biochemistry. The many-body tree methods devised by Barnes and Hutt in the 1980s and the Fast Multipole Method introduced in 1987 by Greengard and Rokhlin use variants of k-d trees to reduce the computation time upper bounds to O(n log n) and even O(n) from O(n2). We present an algorithm that uses the principle of well-separated pairs decomposition to always produce compressed trees in O(n log n) work. We present and evaluate parallel implementations for the algorithm that can take advantage of multi-core architectures.The Science and Technology Facilities Council, UK
Evidence from Meteorites for Multiple Possible Amino Acid Alphabets for the Origins of Life
A key question for the origins of life is understanding which amino acids made up the first proteins synthesized during the origins of life. The canonical set of 20 - 22 amino acids used in proteins are all alpha-amino, alpha-hydrogen isomers that, nevertheless, show considerable variability in properties including size, hydrophobicity, and ionizability. Abiotic amino acid synthesis experiments such as Miller-Urey spark discharge reactions produce a set of up to 23 amino acids, depending on starting materials and reaction conditions, with significant abundances of both alpha- and non-alpha-amino acid isomers. These two sets of amino acids do not completely overlap; of the 23 spark discharge amino acids, only 11 are used in modern proteins. Furthermore, because our understanding of conditions on the early Earth are limited, it is unclear which set(s) of conditions employed in spark discharge or hydrothermal reactions are correct, leaving us with significant uncertainty about the amino acid alphabet available for the origins of life on Earth. Meteorites, the surviving remnants of asteroids and comets that fall to the Earth, offer the potential to study authentic samples of naturally-occurring abiotic chemistry, and thus can provide an alternative approach to constraining the amino acid library during the origins of life
Compound-Specific Isotopic Analysis of Meteoritic Amino Acids as a Tool for Evaluating Potential Formation Pathways
Measurements of stable hydrogen, carbon, and nitrogen isotopic ratios (delta D, delta C-13, delta N-15) of organic compounds can reveal information about their origin and formation pathways. Several formation mechanisms and environments have been postulated for the amino acids detected in carbonaceous chondrites. As each proposed mechanism utilizes different precursor molecules, the isotopic signatures of the resulting amino acids may point towards the most likely of these proposed pathways. The technique of gas chromatography coupled with mass spectrometry and isotope ratio mass spectrometry provides compound-specific structural and isotopic information from a single splitless injection, enhancing the amount of information gained from small amounts of precious samples such as carbonaceous chondrites. We have applied this technique to measure the compound-specific C, N, and H isotopic ratios of amino acids from seven CM and CR carbonaceous chondrites. We are using these measurements to evaluate predictions of expected isotopic enrichments from potential formation pathways and environments, leading to a better understanding of the origin of these compounds
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