1,081 research outputs found
Cosmic-ray exposure ages of fossil micrometeorites from mid-Ordovician sediments at Lynna River, Russia
We measured the He and Ne concentrations of 50 individual extraterrestrial
chromite grains recovered from mid-Ordovician (lower Darriwilian) sediments
from the Lynna River section near St. Petersburg, Russia. High concentrations
of solar wind-like He and Ne found in most grains indicate that they were
delivered to Earth as micrometeoritic dust, while their abundance,
stratigraphic position and major element composition indicate an origin related
to the L chondrite parent body (LCPB) break-up event, 470 Ma ago. Compared to
sediment-dispersed extraterrestrial chromite (SEC) grains extracted from coeval
sediments at other localities, the grains from Lynna River are both highly
concentrated and well preserved. As in previous work, in most grains from Lynna
River, high concentrations of solar wind-derived He and Ne impede a clear
quantification of cosmic-ray produced He and Ne. However, we have found several
SEC grains poor in solar wind Ne, showing a resolvable contribution of
cosmogenic 21Ne. This makes it possible, for the first time, to determine
robust cosmic-ray exposure (CRE) ages in these fossil micrometeorites, on the
order of a few hundred-thousand years. These ages are similar to the CRE ages
measured in chromite grains from cm-sized fossil meteorites recovered from
coeval sediments in Sweden. As the CRE ages are shorter than the orbital decay
time of grains of this size by Poynting-Robertson drag, this suggests that the
grains were delivered to Earth through direct injection into an orbital
resonance. We demonstrate how CRE ages of fossil micrometeorites can be used,
in principle, to determine sedimentation rates, and to correlate the sediments
at Lynna River with the fossil meteorite-bearing sediment layers in Sweden.Comment: 25 pages, 4 figures, 2 table
What evidence is there to support the impact of gardens on health outcomes? A systematic scoping review of the evidence
According to the World Health Organisation Global
Health Observatory (2017), non-communicable diseases
(NCD’s) present a significant cause of death through
cardiovascular disease, respiratory conditions and type
2 diabetes. The impact of NCDs on health and social
care is estimated to outstrip service provision and the
drive to promote health and well-being to tackle the key
causes of NCD’s is at the vanguard of UK, European and
global health care policy. There is a need for health and
social care commissioners to examine and commission
new treatment interventions that can offer multipurpose
interventions for people in the community with LTC and
co-morbid conditions. It is claimed that nature based
activities, such as therapeutic horticulture or gardening
activity, can improve health and wellbeing for a range
of people with long-term conditions. Nature Based
Activities have been defined as ‘an intervention with the
aim to treat, hasten recovery, and/or rehabilitate patients
with a disease or a condition of ill health, with the
fundamental principle that the therapy involves plants,
natural materials, and/or outdoor environment, without
any therapeutic involvement of extra human mammals
or other living creatures’ (Annerstedt & Währborg 2011).
This includes, amongst other activities, gardens as a
nature based activity that encourages individuals to
engage with, observe or access.
This review has located and described research evidence
that has reported on the impact of gardens on physical,
mental, health and well being. A systematic approach
was used to scope the evidence base across a range of
data bases and external sources. The review reports on
the following:
- How gardens can improve physical, mental, health and
wellbeing outcomes
- A ‘map’ of the literature in relation to the benefits for particular
conditions , types of garden, and health outcomes
- The gaps in the literature in relation to particular conditions,
garden types and health outcomes
- Gardens as an intervention within the social prescribing
movement
- Infographics and a logic models, which capture the data in a
simple way. These can be used to inform the future development
of the RHS therapeutic garden and for organisations
interested in green care or nature-based activities
This report has provided an overview of the evidence for
gardens as an intervention that could promote health and
wellbeing in a range of populations. This has significance
for public health and health care as there is a precedence
to explore alternative methods of service provision.
The findings from this review report on the impact
of gardens and gardening on four key areas: Mental
Health, Dementia, Wellbeing, Specific Conditions using
Physiological Outcome Measures and Nutrition. The
review evidence indicated that nature based activities
such as gardens (in the range of formats) can help
social inclusion, self-esteem and perceived wellbeing.
Although the methodologies and interventions varied,
the evidence base overwhelming supported the use of
gardens as an activity that could promote wellbeing.
Moreover, these activities were reflected in the Bragg et
al (2016) Green Framework which suggests that gardens
positively impact on people through everyday life such as
home gardening, health promotion through nature based
activates such as digging and community gardening
through to and green care that uses more structured approaches for people with defined needs
What is the evidence for the impact of gardens and gardening on health and well-being : a scoping review and evidence-based logic model to guide healthcare strategy decision making on the use of gardening approaches as a social prescription
Objective:
To systematically identify and describe studies that have evaluated the impact of gardens
and gardening on health and wellbeing. A secondary objective was to use this evidence to build
evidence-based logic models to guide health strategy decision making about gardens and gardening
as a non-medical, social prescription.
Design:
Scoping review of the impact of gardens and gardening on health and wellbeing. Gardens
include private spaces and those open to the public or part of hospitals, care homes, hospices or third
sector organisations.
Data Sources:
A range of biomedical and health management journals were searched including
Medline, CINAHL, Psychinfo, Web of Knowledge, ASSIA, Cochrane, Joanna Briggs, Greenfile,
Environment Complete and a number of indicative websites were searched to locate context specific
data and grey literature. We searched from 1990 – November 2019.
Eligibility Criteria:
We included research studies (including systematic reviews) that assessed the
effect, value or impact of any garden that met the gardening definition.
Data Extraction and Synthesis:
Three reviewers jointly screened 50 records by titles and abstracts to
ensure calibration. Each record title was screened independently by 2 out of 3 members of the project
team and each abstract was screened by 1 member of a team of 3. Random checks on abstract and
full text screening were conducted by a fourth member of the team and any discrepancies were
resolved through double-checking and discussion.
Results:
From the 8896 papers located, a total of 77* studies were included. Over 35 validated health,
wellbeing and functional biometric outcome measures were reported. Interventions ranged from
viewing gardens, taking part in gardening or undertaking therapeutic activities. The findings
demonstrated links between gardens and improved mental wellbeing, increased physical activity and
a reduction in social isolation enabling the development of 2 logic models.
Conclusions:
Gardens and gardening can improve the health and wellbeing for people with a range of
health and social needs. The benefits of gardens and gardening could be used as a ‘social prescription’
globally, for people with Long Terms Conditions (LTC). Our logic models provide an evidence-based
illustration that can guide health strategy decision making about the referral of people with LTC to
socially prescribed, non-medical interventions involving gardens and gardenin
Incorporating considerations of socio-economic health inequalities in evidence synthesis
Interventions shown to be effective in improving the health of a population may actually widen the health inequalities gap while others reduce it. Therefore, it is imperative that all systematic reviewers consider the potential for their findings to reduce or increase health inequalities. However, challenges arising when incorporating health inequality considerations in systematic reviews relate to the nature of the evidence base, the nature of the review process, the reviewer and lack of guidance available to reviewers. The aim addressed here is how we can enable systematic reviewers to consider a priori whether, and how, an individual’s socio-economic status (i.e. their income, educational or occupational status) may moderate the effectiveness of healthcare interventions, in order to predict the likely impact on socio-economic health inequalities. Methods used to examine this aim included a mapping review of the review guidance on the conduct of systematic reviews considering health inequalities; a methodology study on the use of programme theory to inform considerations of socio-economic health inequalities in systematic reviews; a ‘best fit’ framework synthesis approach in developing a meta-framework and a worked example of meta-framework development. The mapping review found 20 review guidance documents to inform health inequality considerations in systematic reviews. The underlying assumption in the guidance was that reviewers would understand the ways in which an individual’s socio-economic status moderates intervention effectiveness. The guidance advocates the use of theory to inform health inequality considerations in systematic reviews, but offer little practical advice. The methodology study found that the use of theory in socio-economic focused systematic reviews was fragmented and ad-hoc, with little use of formal theory. A meta-framework approach combined two theoretical perspectives (socio-economic health inequalities and complex interventions) into a single framework to inform socio-economic health inequality considerations in systematic reviews. The meta-framework identified factors relating to the type of intervention, implementation, context, participant response, and mechanisms associated with differential effects across socio-economic groups. Methodological challenges in developing a meta-framework to inform evidence synthesis identified include; i) identification of theory, ii) selection of theory, iii) operationalisation of theory and iv) evaluation of theory. The meta-framework can inform socio-economic health inequality considerations at different stages in the review process. In particular, during question formulation, literature searching, data extraction, analyses and synthesis, and assessments of applicability. In the event of a lack of evidence of the impact of socio-economic status on differential effectiveness of health interventions, the theory-led meta-framework can ensure that reviewers base assessments of the applicability of the findings to disadvantaged populations on a posteriori reasoning rather than post-hoc assumptions. In this way, the meta-framework aims to increase the usefulness of systematic reviews in informing healthcare practice and policy
A comprehensive study of noble gases and nitrogen in Hypatia, a diamond-rich pebble from SW Egypt
This is a follow-up study of a work by Kramers et al. (2013) on an unusual
diamond-rich rock found in the SW side of the Libyan Desert Glass strewn field.
This pebble, called Hypatia, is composed of almost pure carbon. Transmission
Electron Microscopy and X-ray diffraction results reveal that Hypatia is made
of defect-rich diamond containing lonsdaleite and deformation bands. These
characteristics are compatible with an impact origin on Earth and/or in space.
We analyzed concentrations and isotopic compositions of all five noble gases
and nitrogen in several mg sized Hypatia samples. These data confirm that
Hypatia is extra-terrestrial. The sample is rich in trapped noble gases with an
isotopic composition close to the meteoritic Q component. 40Ar/36Ar ratios in
individual steps are as low as 0.4. Concentrations of cosmic-ray produced 21Ne
correspond to a nominal cosmic-ray exposure age of ca. 0.1 Myr if produced in a
typical m-sized meteoroid. Such an atypically low nominal exposure age suggests
high shielding in a considerably larger body. In addition to the Xe-Q
composition, an excess of radiogenic 129Xe (from the decay of extinct 129I) is
observed (129Xe/132Xe = 1.18 +/- 0.03). Two N components are present, an
isotopically heavy component ({\delta}15N = +20 permil) released at low temp.
and a major light component ({\delta}15N = -110 permil) at higher temp. This
disequilibrium in N suggests that the diamonds in Hypatia were formed in space.
Our data are broadly consistent with concentrations and isotopic compositions
of noble gases in at least three different types of carbon-rich meteoritic
materials. However, Hypatia does not seem to be related to any of these
materials, but may have sampled a similar cosmochemical reservoir. Our study
does not confirm the presence of exotic noble gases that led Kramers et al. to
propose that Hypatia is a remnant of a comet that impacted the Earth
Age related changes in skeletal muscle mass and function
The loss of muscle mass with age (Sarcopenia) has received growing attention over
the past decade. Despite efforts to provide a universal definition with clinically
meaningful cut-off points for diagnosis, there is no clear consensus on how to best
quantify and assess the impact of loss of muscle mass and function on functional
limitations. Whilst most previous studies have used dual energy x-ray absorptiometry
(DXA) to quantify this loss, chapter 2 of this thesis shows that DXA underestimates
the loss of muscle mass with age in comparison to the gold standard MRI.
Muscle mass per se is not enough to determine whether a person has an
exceptionally low muscle mass, as it can be readily seen that a healthy tall person
will have a larger muscle mass than a small person. Clinicians and researchers thus
need an index of muscle mass that takes differences in stature into account and also
gives an objective cut off point to define low muscle mass. In Chapter3, we show that
femur volume does not significantly differ between young and old. We used this
observation to introduce a new index: thigh muscle mass normalised to femur
volume, or the muscle to bone ratio. This index allows the examination of the true
extent of muscle atrophy within an individual.
In previous studies the appendicular lean mass (determined with DXA)
divided by height squared appeared to be a relatively poor predictor of functional
performance. In Chapter 4, the index introduced in Chapter 3, the muscle to bone
ratio, proved to be a somewhat better predictor of functional performance in the
overall cohort. This was, however, not true when examining the intra-group
relationships. A similar situation applied to the maximal muscle strength. In older
adults, the parameter which predicted functional performance best was muscle
power per body mass, measured during a counter-movement jump.
Chapter 5 shows that part of the larger loss power and force than muscle
mass is attributable to a left-ward shift of the torque-frequency relationship, indicative
of a slowing of the muscle, and reduction in maximal voluntary activation, as
assessed using the interpolated twitch technique in older adults.
Chapter 5 also shows that the fatigue resistance during a series of intermittent
contractions was similar in young and older adults. However, older adults could
sustain a 50% maximal voluntary contraction force longer than young people. Part of
this discrepancy maybe due to an age-related slowing of the muscle
What evidence is there to support the employment of trained and professionally registered library, information and knowledge workers? A systematic scoping review of the evidence
This report seeks to provide evidence that CILIP can use to advocate on behalf of the information professions. The report addresses three aims:1.To create an initial evidence base which can be used to advocate on behalf of the information professions.2.To develop clear propositions outlining the value that trained and professional registered staff provide.3.To identify options for further research which can be commissioned by CILIPIt doe this by:1.Reporting on a systematic scoping review of the literature to identify the evidence base for trained and professionally registered library, information and knowledge (LIK) workers2.Mapping the evidence according to library sector 3.Identifying which evidence bases need updating4.Drawing up a set of propositions from the results of the review and mapping 5.Identifying further research needed and what methods could be used to achieve this
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