1,340 research outputs found
Starting young? children’s experiences of trying smoking during pre-adolescence
Although the risks smoking poses to health are now well known, many young people continue to take up the habit. While numerous crosssectional studies of adolescents have identified correlates of smoking initiation, much less prospective, longitudinal research has been conducted
with young children to gather their accounts of early experiences of smoking, and this study fills that significant gap. Quantitative and qualitative data, collected using questionnaires, interviews and focus groups, are presented from the pre-adolescent phase of the
Liverpool Longitudinal Study of Smoking. By age 11, 27% of the cohort had tried smoking, 13% had smoked repeatedly and 3% were smoking regularly. Rates of experimentation increased over time. Qualitative data revealed that curiosity and the role of peers were central to children’s accounts of early smoking. By preadolescence, children are at different stages in their smoking careers, therefore interventionsmust be targeted to their varied experiences.
Current prevention strategies often focus on restricting access to cigarettes, but a broad range of intervention measures is required which take account of the multifactorial nature of smoking onset. To be effective, policies that aim to prevent smoking must be grounded in
children’s lived experiences
Evaluation of Weight Change During Carboplatin Therapy in Dogs With Appendicular Osteosarcoma.
BackgroundThe prevalence of cancer cachexia in veterinary medicine has not been studied widely, and as of yet, no definitive diagnostic criteria effectively assess this syndrome in veterinary patients.Objectives(1) To determine the patterns of weight change in dogs with appendicular osteosarcoma treated with amputation and single-agent carboplatin during the course of adjuvant chemotherapy; and (2) to determine whether postoperative weight change is a negative prognostic indicator for survival time in dogs with osteosarcoma.AnimalsEighty-eight dogs diagnosed with appendicular osteosarcoma. Animals were accrued from 3 veterinary teaching hospitals.MethodsRetrospective, multi-institutional study. Dogs diagnosed with appendicular osteosarcoma and treated with limb amputation followed by a minimum of 4 doses of single-agent carboplatin were included. Data analyzed in each patient included signalment, tumor site, preoperative serum alkaline phosphatase activity (ALP), and body weight (kg) at each carboplatin treatment.ResultsA slight increase in weight occurred over the course of chemotherapy, but this change was not statistically significant. Weight change did not have a significant effect on survival. Institution, patient sex, and serum ALP activity did not have a significant effect on survival.Conclusions and clinical importanceWeight change was not a prognostic factor in these dogs, and weight loss alone may not be a suitable method of determining cancer cachexia in dogs with appendicular osteosarcoma
Scalable Substrate Development for Aqueous Biological Samples for Atom Probe Tomography
Reliable and consistent preparation of atom probe tomography (APT) specimens
from aqueous and hydrated biological specimens remains a significant challenge.
One particularly difficult process step is the use of a focused ion beam (FIB)
instrument for preparing the required needle-shaped specimen, typically
involving a "lift-out" procedure of a small sample of material. Here, two
alternative substrate designs are introduced that enable using FIB only for
sharpening, along with example APT datasets. The first design is a laser-cut
FIB-style half-grid close to those used for transmission-electron microscopy,
that can be used in a grid holder compatible with APT pucks. The second design
is a larger, standalone self-supporting substrate called a "crown", with
several specimen positions that self-aligns in APT pucks, prepared by
electrical discharge machining (EDM). Both designs are made nanoporous, to
provide strength to the liquid-substrate interface, using chemical and vacuum
dealloying. We select alpha brass a simple, widely available, lower-cost
alternative to previously proposed substrates. We present the resulting
designs, APT data, and provide suggestions to help drive wider community
adoption
Facilitating the systematic nanoscale study of battery materials by atom probe tomography through in-situ metal coating
Through its capability for 3D mapping of Li at the nanoscale, atom probe
tomography (APT) is poised to play a key role in understanding the
microstructural degradation of lithium-ion batteries (LIB) during successive
charge and discharge cycles. However, APT application to materials for LIB is
plagued by the field induced delithiation (deintercalation) of Li-ions during
the analysis itself that prevents the precise assessment of the Li
distribution. Here, we showcase how a thin Cr-coating, in-situ formed on APT
specimens of NMC811 in the focused-ion beam (FIB), preserves the sample's
integrity and circumvent this deleterious delithiation. Cr-coated specimens
demonstrated remarkable improvements in data quality and virtually eliminated
premature specimen failures, allowing for more precise measurements via.
improved statistics. Through improved data analysis, we reveal substantial
cation fluctuations in commercial grade NMC811, including complete grains of
LiMnO. The current methodology stands out for its simplicity and
cost-effectiveness and is a viable approach to prepare battery cathodes and
anodes for systematic APT studies
Valkai András (1540–1586) Báthory-genealógiája. Báthory István király mint az Árpádok leszármazottja
Purpose Heat adaptation (HA) is critical to performance and health in a hot environment. Transition from short-term heat acclimatisation (STHA) to long-term heat acclimatisation (LTHA) is characterised by decreased autonomic disturbance and increased protection from thermal injury. A standard heat tolerance test (HTT) is recommended for validating exercise performance status, but any role in distinguishing STHA from LTHA is unreported. The aims of this study were to (1) define performance status by serial HTT during structured natural HA, (2) evaluate surrogate markers of autonomic activation, including heart rate variability (HRV), in relation to HA status. Methods Participants (n = 13) were assessed by HTT (60-min block-stepping, 50% VO2peak) during STHA (Day 2, 6 and 9) and LTHA (Day 23). Core temperature (Tc) and heart rate (HR) were measured every 5 min. Sampling for HRV indices (RMSSD, LF:HF) and sympathoadrenal blood measures (cortisol, nephrines) was undertaken before and after (POST) each HTT. Results Significant (P < 0.05) interactions existed for Tc, logLF:HF, cortisol and nephrines (two-way ANOVA; HTT by Day). Relative to LTHA, POST results differed significantly for Tc (Day 2, 6 and 9), HR (Day 2), logRMSSD (Day 2 and Day 6), logLF:HF (Day 2 and Day 6), cortisol (Day 2) and nephrines (Day 2 and Day 9). POST differences in HRV (Day 6 vs. 23) were + 9.9% (logRMSSD) and − 18.6% (logLF:HF). Conclusions Early reductions in HR and cortisol characterised STHA, whereas LTHA showed diminished excitability by Tc, HRV and nephrine measures. Measurement of HRV may have potential to aid real-time assessment of readiness for activity in the heat
Behavior therapy for pediatric trichotillomania: Exploring the effects of age on treatment outcome
<p>Abstract</p> <p>Background</p> <p>A randomized controlled trial examining the efficacy of behavior therapy for pediatric trichotillomania was recently completed with 24 participants ranging in age from 7 - 17. The broad age range raised a question about whether young children, older children, and adolescents would respond similarly to intervention. In particular, it is unclear whether the younger children have the cognitive capacity to understand concepts like "urges" and whether they are able to introspect enough to be able to benefit from awareness training, which is a key aspect of behavior therapy for trichotillomania.</p> <p>Methods</p> <p>Participants were randomly assigned to receive either behavior therapy (N = 12) or minimal attention control (N = 12), which was included to control for repeated assessments and the passage of time. Primary outcome measures were the independent evaluator-rated NIMH-Trichotillomania Severity Scale, a semi-structured interview often used in trichotillomania treatment trials, and a post-treatment clinical global impression improvement rating (CGI-I).</p> <p>Results</p> <p>The correlation between age and change in symptom severity for all patients treated in the trial was small and not statistically significant. A 2 (group: behavioral therapy, minimal attention control) × 2 (time: week 0, 8) × 2 (children < 9 yrs., children > 10) ANOVA with independent evaluator-rated symptom severity scores as the continuous dependent variable also detected no main effects for age or for any interactions involving age. In light of the small sample size, the mean symptom severity scores at weeks 0 and 8 for younger and older patients randomized to behavioral therapy were also plotted. Visual inspection of these data indicated that although the groups appeared to have started at similar levels of severity for children ≤ 9 vs. children ≥ 10; the week 8 data show that the three younger children did at least as well as if not slightly better than the nine older children and adolescents.</p> <p>Conclusions</p> <p>Behavior therapy for pediatric trichotillomania appears to be efficacious even in young children. The developmental and clinical implications of these findings will be discussed.</p> <p>Trial Registration</p> <p>Clinicaltrials.gov NCT00043563.</p
Nutritional status and the gonadotrophic response to a polar expedition.
Polar expeditions have been associated with changes in the hypothalamic-pituitary-testicular axis consistent with central hypogonadism (i.e., decreased testosterone, luteinising hormone (LH), and follicle stimulating hormone (FSH)). These changes are typically associated with body mass loss. Our aim was to evaluate whether maintenance of body mass during a polar expedition could mitigate against the development of central hypogonadism. Male participants (n = 22) from a 42-day expedition (British Services Antarctic Expedition 2012) volunteered to take part in the study. Body mass, body composition, and strength data were recorded pre- and postexpedition in addition to assessment of serum testosterone, LH, FSH, thyroid hormones, insulin-like growth factor 1 (IGF-1), and trace elements. Energy provision and energy expenditure were assessed at mid- and end-expedition. Daily energy provision was 6335 ± 149 kcal·day(-1). Estimated energy expenditure midexpedition was 5783 ± 1690 kcal·day(-1). Body mass and percentage body fat did not change between pre- and postexpedition. Total testosterone (nmol·L(-1)) (14.0 ± 4.9 vs. 17.3 ± 4.0, p = 0.006), calculated free testosterone (pmol·L(-1)) (288 ± 82 vs. 350 ± 70, p = 0.003), and sex hormone binding globulin (nmol·L(-1)) (33 ± 12 vs. 36 ± 11, p = 0.023) concentrations increased. LH and FSH remained unchanged. Thyroid stimulating hormone (TSH; IU·L(-1)) (2.1 ± 0.8 vs. 4.1 ± 2.1, p < 0.001) and free triiodothyronine (FT3; IU·L(-1)) (5.4 ± 0.4 vs. 6.1 ± 0.8, p < 0.001) increased while free thyroxine, IGF-1, and trace elements remained unchanged. Hand-grip strength was reduced postexpedition but static lift strength was maintained. Maintenance of body mass and nutritional status appeared to negate the central hypogonadism previously reported from polar expeditions. The elevated TSH and free FT3 were consistent with a previously reported "polar T3 syndrome"
A versatile and reproducible cryo-sample preparation methodology for atom probe studies
Repeatable and reliable site-specific preparation of specimens for atom probe
tomography (APT) at cryogenic temperatures has proven challenging. A
generalized workflow is required for cryogenic-specimen preparation including
lift-out via focused-ion beam and in-situ deposition of capping layers, to
strengthen specimens that will be exposed to high electric field and stresses
during field evaporation in APT, and protect them from environment during
transfer into the atom probe. Here, we build on existing protocols, and
showcase preparation and analysis of a variety of metals, oxides and supported
frozen liquids and battery materials. We demonstrate reliable in-situ
deposition of a metallic capping layer that significantly improve the atom
probe data quality for challenging material systems, particularly battery
cathode materials which are subjected to delithiation during the atom probe
analysis itself. Our workflow designed is versatile and transferable widely to
other instruments
Analysis of water ice in nanoporous copper needles using cryo atom probe tomography
The application of atom probe tomography (APT) to frozen liquids is limited
by difficulties in specimen preparation. Here, we report on the use of
nanoporous Cu needles as a physical framework to hold water ice for
investigation using APT. Nanoporous Cu needles are prepared by the
electropolishing and dealloying of Cu-Mn matchstick precursors. Cryogenic
scanning electron microscopy and focused-ion beam milling reveal a
hierarchical, dendritic, highly-wettable microstructure. The atom probe mass
spectrum is dominated by peaks of Cu+ and H(H2O)n+ up to n <= 3, and the
reconstructed volume shows the protrusion of a Cu ligament into an ice-filled
pore. The continuous Cu ligament network electrically connects the apex to the
cryostage, leading to enhanced electric field at the apex and increased
cooling, both of which simplify the mass spectrum compared to previous reports
Community-based randomised controlled trial evaluating falls and osteoporosis risk management strategies
<p>Abstract</p> <p>Background</p> <p>Osteoporosis-related fractures are a significant public health concern. Interventions that increase detection and treatment of osteoporosis, as well as prevention of fractures and falls, are substantially underutilized. This paper outlines the protocol for a pragmatic randomised trial of a multifaceted community-based care program aimed at optimizing the evidence-based management of falls and fractures in patients at risk.</p> <p>Design</p> <p>6-month randomised controlled study.</p> <p>Methods</p> <p>This population-based study was completed in the Algoma District of Ontario, Canada a geographically vast area with Sault Ste Marie (population 78 000) as its main city. Eligible patients were allocated to an immediate intervention protocol (IP) group, or a delayed intervention protocol (DP) group. The DP group received usual care for 6 months and then was crossed over to receive the interventions. Components of the intervention were directed at the physicians and their patients and included patient-specific recommendations for osteoporosis therapy as outlined by the clinical practice guidelines developed by Osteoporosis Canada, and falls risk assessment and treatment. Two primary outcomes were measured including implementation of appropriate osteoporosis and falls risk management. Secondary outcomes included quality of life and the number of falls, fractures, and hospital admissions over a twelve-month period. The patient is the unit of allocation and analysis. Analyses will be performed on an intention to treat basis.</p> <p>Discussion</p> <p>This paper outlines the protocol for a pragmatic randomised trial of a multi-faceted, community-based intervention to optimize the implementation of evidence based management for patients at risk for falls and osteoporosis.</p> <p>Trial Registration</p> <p>This trial has been registered with clinicaltrials.gov (ID: NCT00465387)</p
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