105 research outputs found

    Environmentally friendly sound absorbing noise barrier made from concrete waste - further developments

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    This paper reports on the second phase of a research project aimed at the development of an environmentally friendly noise barrier for urban freeways, also known as KMAK [1]. The concrete barrier, which has some unique capabilities to mitigate transportation noise, is made from recycled concrete (RC) aggregate and industrial by-products such as fly ash and reclaimed water. The current developmental work expands on a research project that resulted in a two-layer (2L) concrete barrier. Two prototypes of the 2L barrier were produced, followed by extensive acoustic testing and a number of simulations where standard timber and/or concrete barriers were substituted with KMAK barrier [2]. Current research investigates a variety of architectural finishes applied to the original KMAK barrier with the aim of improving its visual appearance and also fine-tuning its acoustic performance. The new three-layer (3L) barrier optimizes sound absorption in a frequency range characteristic similar to that of transportation noise, especially road traffic noise. Three major aspects related to the development of architectural finishes were considered; environmentally responsible materials, surface features, and production methods. The findings of the current investigation demonstrate that there is a positive correlation between surface features, percentage of perforation as well as depth of the architectural layer, and increased potential of the 3L barrier to mitigate transportation noise. On average, the addition of perforated architectural finish contributes to a 20% increase in sound absorption. The preliminary results also show that the sound absorbency of the 3L barrier can be better controlled and tuned to specific noise frequency than the 2L type. The visual appearance has been significantly improved with the addition of the architectural finish, which makes the barrier an attractive, feasible, and viable alternative to road barriers made from standard concrete or timber.<br /

    Common mental disorders and ethnicity in England : the EMPIRIC Study

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    Background. There is little population-based evidence on ethnic variation in the most common mental disorders (CMD), anxiety and depression. We compared the prevalence of CMD among representative samples of White, Irish, Black Caribbean, Bangladeshi, Indian and Pakistani individuals living in England using a standardized clinical interview. Method. Cross-sectional survey of 4281 adults aged 16–74 years living in private households in England. CMD were assessed using the Revised Clinical Interview Schedule (CIS-R), a standardized clinical interview. Results. Ethnic differences in the prevalence of CMD were modest, and some variation with age and sex was noted. Compared to White counterparts, the prevalence of CMD was higher to a statistically significant degree among Irish [adjusted rate ratios (RR) 2.09, 95% CI 1.16–2.95, p=0.02] and Pakistani (adjusted RR 2.38, 95% CI 1.25–3.53, p=0.02) men aged 35–54 years, even after adjusting for differences in socio-economic status. Higher rates of CMD were also observed among Indian and Pakistani women aged 55–74 years, compared to White women of similar age. The prevalence of CMD among Bangladeshi women was lower than among White women, although this was restricted to those not interviewed in English. There were no differences in rates between Black Caribbean and White samples. Conclusions. Middle-aged Irish and Pakistani men, and older Indian and Pakistani women, had significantly higher rates of CMD than their White counterparts. The very low prevalence of CMD among Bangladeshi women contrasted with high levels of socio-economic deprivation among this group. Further study is needed to explore reasons for this variation

    The Utility of Transient Sensitivity for Wildlife Management and Conservation: Bison as a Case Study

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    Developing effective management strategies is essential to conservation biology. Population models and sensitivity analyses on model parameters have provided a means to quantitatively compare different management strategies, allowing managers to objectively assess the resulting impacts. Inference from traditional sensitivity analyses (i.e., eigenvalue sensitivity methods) is only valid for a population at its stable age distribution, while more recent methods have relaxed this assumption and instead focused on transient population dynamics. However, very few case studies, especially in long-lived vertebrates where transient dynamics are potentially most relevant, have applied these transient sensitivity methods and compared them to eigenvalue sensitivity methods. We use bison (Bison bison) at Badlands National Park as a case study to demonstrate the benefits of transient methods in a practical management scenario involving culling strategies. Using an age and stage-structured population model that incorporates culling decisions, we find that culling strategies over short time-scales (e.g., 1–5 years) are driven largely by the standing population distribution. However, over longer time-scales (e.g., 25 years), culling strategies are governed by reproductive output. In addition, after 25 years, the strategies predicted by transient methods qualitatively coincide with those predicted by traditional eigenvalue sensitivity. Thus, transient sensitivity analyses provide managers with information over multiple time-scales in contrast to the long time-scales associated with eigenvalue sensitivity analyses. This flexibility is ideal for adaptive management schemes and allows managers to balance short-term goals with long-term viability

    The effect of a brief social intervention on the examination results of UK medical students: a cluster randomised controlled trial

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    Background: Ethnic minority (EM) medical students and doctors underperform academically, but little evidence exists on how to ameliorate the problem. Psychologists Cohen et al. recently demonstrated that a written self-affirmation intervention substantially improved EM adolescents' school grades several months later. Cohen et al.'s methods were replicated in the different setting of UK undergraduate medical education.Methods: All 348 Year 3 white (W) and EM students at one UK medical school were randomly allocated to an intervention condition (writing about one's own values) or a control condition (writing about another's values), via their tutor group. Students and assessors were blind to the existence of the study. Group comparisons on post-intervention written and OSCE (clinical) assessment scores adjusted for baseline written assessment scores were made using two-way analysis of covariance. All assessment scores were transformed to z-scores (mean = 0 standard deviation = 1) for ease of comparison. Comparisons between types of words used in essays were calculated using t-tests. The study was covered by University Ethics Committee guidelines.Results: Groups were statistically identical at baseline on demographic and psychological factors, and analysis was by intention to treat [intervention group EM n = 95, W n = 79; control group EM n = 77; W n = 84]. As predicted, there was a significant ethnicity by intervention interaction [F(4,334) = 5.74; p = 0.017] on the written assessment. Unexpectedly, this was due to decreased scores in the W intervention group [mean difference = 0.283; (95% CI = 0.093 to 0.474] not improved EM intervention group scores [mean difference = -0.060 (95% CI = -0.268 to 0.148)]. On the OSCE, both W and EM intervention groups outperformed controls [mean difference = 0.261; (95% CI = -0.047 to -0.476; p = 0.013)]. The intervention group used more optimistic words (p < 0.001) and more "I" and "self" pronouns in their essays (p < 0.001), whereas the control group used more "other" pronouns (p < 0.001) and more negations (p < 0.001).Discussion: Cohen et al.'s finding that a brief self-affirmation task narrowed the ethnic academic achievement gap was replicated on the written assessment but against expectations, this was due to reduced performance in the W group. On the OSCE, the intervention improved performance in both W and EM groups. In the intervention condition, participants tended to write about themselves and used more optimistic words than in the control group, indicating the task was completed as requested. The study shows that minimal interventions can have substantial educational outcomes several months later, which has implications for the multitude of seemingly trivial changes in teaching that are made on an everyday basis, whose consequences are never formally assessed

    Self-monitoring of blood pressure in hypertension: A systematic review and individual patient data meta-analysis.

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    BACKGROUND: Self-monitoring of blood pressure (BP) appears to reduce BP in hypertension but important questions remain regarding effective implementation and which groups may benefit most. This individual patient data (IPD) meta-analysis was performed to better understand the effectiveness of BP self-monitoring to lower BP and control hypertension. METHODS AND FINDINGS: Medline, Embase, and the Cochrane Library were searched for randomised trials comparing self-monitoring to no self-monitoring in hypertensive patients (June 2016). Two reviewers independently assessed articles for eligibility and the authors of eligible trials were approached requesting IPD. Of 2,846 articles in the initial search, 36 were eligible. IPD were provided from 25 trials, including 1 unpublished study. Data for the primary outcomes-change in mean clinic or ambulatory BP and proportion controlled below target at 12 months-were available from 15/19 possible studies (7,138/8,292 [86%] of randomised participants). Overall, self-monitoring was associated with reduced clinic systolic blood pressure (sBP) compared to usual care at 12 months (-3.2 mmHg, [95% CI -4.9, -1.6 mmHg]). However, this effect was strongly influenced by the intensity of co-intervention ranging from no effect with self-monitoring alone (-1.0 mmHg [-3.3, 1.2]), to a 6.1 mmHg (-9.0, -3.2) reduction when monitoring was combined with intensive support. Self-monitoring was most effective in those with fewer antihypertensive medications and higher baseline sBP up to 170 mmHg. No differences in efficacy were seen by sex or by most comorbidities. Ambulatory BP data at 12 months were available from 4 trials (1,478 patients), which assessed self-monitoring with little or no co-intervention. There was no association between self-monitoring and either lower clinic or ambulatory sBP in this group (clinic -0.2 mmHg [-2.2, 1.8]; ambulatory 1.1 mmHg [-0.3, 2.5]). Results for diastolic blood pressure (dBP) were similar. The main limitation of this work was that significant heterogeneity remained. This was at least in part due to different inclusion criteria, self-monitoring regimes, and target BPs in included studies. CONCLUSIONS: Self-monitoring alone is not associated with lower BP or better control, but in conjunction with co-interventions (including systematic medication titration by doctors, pharmacists, or patients; education; or lifestyle counselling) leads to clinically significant BP reduction which persists for at least 12 months. The implementation of self-monitoring in hypertension should be accompanied by such co-interventions

    Self-monitoring of blood pressure in hypertension: A systematic review and individual patient data meta-analysis

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    Background: Self-monitoring of blood pressure (BP) appears to reduce BP in hypertension but important questions remain regarding effective implementation and which groups may benefit most. This individual patient data (IPD) meta-analysis was performed to better understand the effectiveness of BP self-monitoring to lower BP and control hypertension.Methods and findings:Medline, Embase, and the Cochrane Library were searched for randomised trials comparing self-monitoring to no self-monitoring in hypertensive patients (9June 2016). Two reviewers independently assessed articles for eligibility and the authors of eligible trials were approached requesting IPD. Of 2,846 articles in the initial search, 36 were eligible. IPD were provided from 25 trials, including 1 unpublished study. Data for the primary outcomes-change in mean clinic or ambulatory BP and proportion controlled below target at 12 months-were available from 15/19 possible studies (97,138/8,292 [86%] of randomised participants). Overall, self-monitoring was associated with reduced clinic systolic blood pressure (9sBP) compared to usual care at 12 months (-3.2 mmHg, [95% CI -4.9, -1.6 mmHg]). However, this effect was strongly influenced by the intensity of co-intervention ranging from no effect with self-monitoring alone (-1.0 mmHg [-3.3, 1.2]), to a 6.1 mmHg (-9.0, -3.2) reduction when monitoring was combined with intensive support. Self-monitoring was most effective in those with fewer antihypertensive medications and higher baseline sBP up to 170 mmHg. No differences in efficacy were seen by sex or by most comorbidities. Ambulatory BP data at 12 months were available from 4 trials (91,478 patients), which assessed selfmonitoring with little or no co-intervention. There was no association between self-monitoring and either lower clinic or ambulatory sBP in this group (9clinic -0.2 mmHg [-2.2, 1.8]; ambulatory 1.1 mmHg [-0.3, 2.5]). Results for diastolic blood pressure (9dBP) were similar. The main limitation of this work was that significant heterogeneity remained. This was at least in part due to different inclusion criteria, self-monitoring regimes, and target BPs in included studies.Conclusions: Self-monitoring alone is not associated with lower BP or better control, but in conjunction with co-interventions (9including systematic medication titration by doctors, pharmacists, or patients; education; or lifestyle counselling) leads to clinically significant BP reduction which persists for at least 12 months. The implementation of self-monitoring in hypertension should be accompanied by such co-interventions.</p

    Individual patient data meta-analysis of self-monitoring of blood pressure (BP-SMART): a protocol.

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    INTRODUCTION: Self-monitoring of blood pressure is effective in reducing blood pressure in hypertension. However previous meta-analyses have shown a considerable amount of heterogeneity between studies, only part of which can be accounted for by meta-regression. This may be due to differences in design, recruited populations, intervention components or results among patient subgroups. To further investigate these differences, an individual patient data (IPD) meta-analysis of self-monitoring of blood pressure will be performed. METHODS AND ANALYSIS: We will identify randomised trials that have compared patients with hypertension who are self-monitoring blood pressure with those who are not and invite trialists to provide IPD including clinic and/or ambulatory systolic and diastolic blood pressure at baseline and all follow-up points where both intervention and control groups were measured. Other data requested will include measurement methodology, length of follow-up, cointerventions, baseline demographic (age, gender) and psychosocial factors (deprivation, quality of life), setting, intensity of self-monitoring, self-monitored blood pressure, comorbidities, lifestyle factors (weight, smoking) and presence or not of antihypertensive treatment. Data on all available patients will be included in order to take an intention-to-treat approach. A two-stage procedure for IPD meta-analysis, stratified by trial and taking into account age, sex, diabetes and baseline systolic BP will be used. Exploratory subgroup analyses will further investigate non-linear relationships between the prespecified variables. Sensitivity analyses will assess the impact of trials which have and have not provided IPD. ETHICS AND DISSEMINATION: This study does not include identifiable data. Results will be disseminated in a peer-reviewed publication and by international conference presentations. CONCLUSIONS: IPD analysis should help the understanding of which self-monitoring interventions for which patient groups are most effective in the control of blood pressure

    Self-monitoring of blood pressure in patients with hypertension related multi-morbidity: Systematic review and individual patient data meta-analysis

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    BACKGROUND Studies have shown that self-monitoring of blood pressure (BP) is effective when combined with co-interventions, but its efficacy varies in the presence of some co-morbidities. This study examined whether self-monitoring can reduce clinic BP in patients with hypertension-related co-morbidity. METHODS A systematic review was conducted of articles published in Medline, Embase, and the Cochrane Library up to January 2018. Randomized controlled trials of self-monitoring of BP were selected and individual patient data (IPD) were requested. Contributing studies were prospectively categorized by whether they examined a low/high-intensity co-intervention. Change in BP and likelihood of uncontrolled BP at 12 months were examined according to number and type of hypertension-related co-morbidity in a one-stage IPD meta-analysis. RESULTS A total of 22 trials were eligible, 16 of which were able to provide IPD for the primary outcome, including 6,522 (89%) participants with follow-up data. Self-monitoring was associated with reduced clinic systolic BP compared to usual care at 12-month follow-up, regardless of the number of hypertension-related co-morbidities (−3.12 mm Hg, [95% confidence intervals −4.78, −1.46 mm Hg]; P value for interaction with number of morbidities = 0.260). Intense interventions were more effective than low-intensity interventions in patients with obesity (P < 0.001 for all outcomes), and possibly stroke (P < 0.004 for BP control outcome only), but this effect was not observed in patients with coronary heart disease, diabetes, or chronic kidney disease. CONCLUSIONS Self-monitoring lowers BP regardless of the number of hypertension-related co-morbidities, but may only be effective in conditions such obesity or stroke when combined with high-intensity co-interventions.</div

    An evidence-based approach to the use of telehealth in long-term health conditions: development of an intervention and evaluation through pragmatic randomised controlled trials in patients with depression or raised cardiovascular risk

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    Background: Health services internationally are exploring the potential of telehealth to support the management of the growing number of people with long-term conditions (LTCs). Aim: To develop, implement and evaluate new care programmes for patients with LTCs, focusing on two common LTCs as exemplars: depression or high cardiovascular disease (CVD) risk. Methods Development: We synthesised quantitative and qualitative evidence on the effectiveness of telehealth for LTCs, conducted a qualitative study based on interviews with patients and staff and undertook a postal survey to explore which patients are interested in different forms of telehealth. Based on these studies we developed a conceptual model [TElehealth in CHronic disease (TECH) model] as a framework for the development and evaluation of the Healthlines Service for patients with LTCs. Implementation: The Healthlines Service consisted of regular telephone calls to participants from health information advisors, supporting them to make behaviour change and to use tailored online resources. Advisors sought to optimise participants’ medication and to improve adherence. Evaluation: The Healthlines Service was evaluated with linked pragmatic randomised controlled trials comparing the Healthlines Service plus usual care with usual care alone, with nested process and economic evaluations. Participants were adults with depression or raised CVD risk recruited from 43 general practices in three areas of England. The primary outcome was response to treatment and the secondary outcomes included anxiety (depression trial), individual risk factors (CVD risk trial), self-management skills, medication adherence, perceptions of support, access to health care and satisfaction with treatment. Trial results Depression trial: In total, 609 participants were randomised and the retention rate was 86%. Response to treatment [Patient Health Questionnaire 9-items (PHQ-9) reduction of ≥ 5 points and score of < 10 after 4 months] was higher in the intervention group (27%, 68/255) than in the control group (19%, 50/270) [odds ratio 1.7, 95% confidence interval (CI) 1.1 to 2.5; p = 0.02]. Anxiety also improved. Intervention participants reported better access to health support, greater satisfaction with treatment and small improvements in self-management, but not improved medication adherence. CVD risk trial: In total, 641 participants were randomised and the retention rate was 91%. Response to treatment (maintenance of/reduction in QRISK®2 score after 12 months) was higher in the intervention group (50%, 148/295) than in the control group (43%, 124/291), which does not exclude a null effect (odds ratio 1.3, 95% CI 1.0 to 1.9; p = 0.08). The intervention was associated with small improvements in blood pressure and weight, but not smoking or cholesterol. Intervention participants were more likely to adhere to medication, reported better access to health support and greater satisfaction with treatment, but few improvements in self-management. The Healthlines Service was likely to be cost-effective for CVD risk, particularly if the benefits are sustained, but not for depression. The intervention was implemented largely as planned, although initial delays and later disruption to delivery because of the closure of NHS Direct may have adversely affected participant engagement. Conclusion: The Healthlines Service, designed using an evidence-based conceptual model, provided modest health benefits and participants valued the better access to care and extra support provided. This service was cost-effective for CVD risk but not depression. These findings of small benefits at extra cost are consistent with previous pragmatic research on the implementation of comprehensive telehealth programmes for LTCs
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