229 research outputs found

    Primjena metode odzivnih površina i neuronskih mreža za modeliranje i procjenu otpornosti na abrazijsko trošenje Poly oxy metilena

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    In this study, abrasive wear behaviour of poly oxy methylenes (POM) under various testing conditions was investigated. A central composite design (CCD) was used to describe response and to estimate the parameters in the model. Response surface methodology (RSM) was adopted to obtain an empirical model of wear loss as a function of applied load and sliding distance. Also, a neural network (NN) model was developed for the prediction and testing of the results. Finally, a comparison was made between the results obtained from RSM and NN.U radu je istraživano abrazijsko trošenje poly oxy metilena (POM), za različite uvjete ispitivanja. Za procjenu parametara modela i odziva, primijenjen je centralno kompozitni plan pokusa. Primjenom metode odzivnih površina dobiven je matematički model ovisnosti gubitka mase o primijenjenom opterećenju i putu klizanja. Također, primjenom neuronskih mreža, razvijen je model za procjenu i testiranje rezultata. Na kraju su uspoređeni rezultati modela, dobiveni metodom odzivnih površina i primjenom neuronskih mreža

    UK clinicians’ views on the use of formulations for the management of BPSD: a multidisciplinary survey

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    © 2020 Informa UK Limited, trading as Taylor & Francis Group. Background and objectives: The process of formulating in the area of dementia care is at an early stage of development. A review published in 2016, identified 14 different types of formulation-based approaches for the management of Behavioural and Psychological Symptoms of Dementia (BPSD). The present study examines professionals’ views about the use of systematic formulations for choosing first-line non-pharmacological interventions for BPSD. Methods: A 34-item online survey, with six items about formulation-based interventions for the management of BPSD, was circulated to multi-disciplinary UK dementia networks. Quantitative data were examined for the use of formulation-based frameworks in practice. Thematic analyses provided insight into the practicalities of using formulations. Results: The majority of the 355 participants responding to the questions stated they used formulation-led models to inform interventions, but 24% stated they did not. Thirty-two types of formulation frameworks were named, and there was a diverse spread across the UK. The Newcastle model was the most frequently used framework, with fifty percent of the participants who formulated reporting using this framework. Four themes regarding the use of formulation emerged, relating to function, process, reported outcomes and obstacles. Conclusion: Formulation-based approaches to targeting intervention are becoming popular in dementia care in the UK. More types of formulation frameworks are used in practice compared with the 2016 review. The use of formulations are seen as key to offering an alternative to pharmacological treatments. Understanding both the value of formulation-led approaches and the obstacles to their use are important to implementing NICE 2018 recommendations

    Challenging behaviour in dementia care: A novel framework for translating knowledge to practice

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    This article provides guidance on the management of challenging behaviours (CBs) in dementia care, and introduces concepts from positive behavioural support not usually applied to dementia. While the use of formulations has received a lot of attention in recent years, the mechanisms of how to apply the formulation-led interventions requires more consideration. In order to assist caregivers to deliver effective interventions we need to have a better understanding of the CBs we are attempting to manage, and also produce management strategies with clearer goals. Ideally we would also want caregivers to be able to describe the skills they employ in a coherent manner in order to facilitate selfreflection and to be able to pass on their skills to junior colleagues. This paper attempts to fulfil these needs by integrating two new models with philosophies already used in dementia care. In terms of new concepts, the first is the Arousal Cycle, which gives caregivers an awareness of the five phases of a typical CB (wellbeing, trigger, escalation, CB, and recovery phase). In relation to the second, the Traffic Light analogy examines CBs in terms of four management stages: Primary prevention, secondary prevention, reactive strategies, and calming strategies. It is proposed that we distinguish between these stages when composing our formulations and care plans, and thereby produce better targeted interventions. By the end of the paper the reader will have been presented with material integrating concepts from the fields of dementia and intellectual impairment, and been introduced to new ways of managing CBs

    Reducing stillbirths: behavioural and nutritional interventions before and during pregnancy

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    Background:The vast majority of global stillbirths occur in low- and middle-income countries, and in many settings, the majority of stillbirths occur antenatally, prior to the onset of labour. Poor nutritional status, lack of antenatal care and a number of behaviours increase women\u27s risk of stillbirth in many resource-poor settings. Interventions to reduce these risks could reduce the resulting burden of stillbirths, but the evidence for the impact of such interventions has not yet been comprehensively evaluated. Methods: This second paper of a systematic review of interventions that could plausibly impact stillbirth rates covers 12 different interventions relating to behavioural and socially mediated risk factors, including exposures to harmful practices and substances, antenatal care utilisation and quality, and maternal nutrition before and during pregnancy. The search strategy reviewed indexed medical journals on PubMed and the Cochrane Library. If any eligible randomised controlled trials were identified that were published after the most recent Cochrane review, they were added to generate new meta-analyses. Interventions covered in this paper have a focus on low- and middle-income countries, both because of the large burden of stillbirths and because of the high prevalence of risk factors including maternal malnutrition and harmful environmental exposures. The reviews and studies belonging to these interventions were graded and conclusions derived about the evidence of benefit of these interventions. Results: From a programmatic perspective, none of the interventions achieved clear evidence of benefit. Evidence for some socially mediated risk factors were identified, such as exposure to indoor air pollution and birth spacing, but still require the development of appropriate interventions. There is a need for additional studies on culturally appropriate behavioural interventions and clinical trials to increase smoking cessation and reduce exposure to smokeless tobacco. Balanced protein-energy supplementation was associated with reduced stillbirth rates, but larger well-designed trials are required to confirm findings. Peri-conceptional folic acid supplementation significantly reduces neural tube defects, yet no significant associated reductions in stillbirth rates have been documented. Evidence for other nutritional interventions including multiple micronutrient and Vitamin A supplementation is weak, suggesting the need for further research to assess potential of nutritional interventions to reduce stillbirths. Conclusion: Antenatal care is widely used in low- and middle-income countries, and provides a natural facility-based contact through which to provide or educate about many of the interventions we reviewed. The impact of broader socially mediated behaviors, such as fertility decision-making, access to antenatal care, and maternal diet and exposures like tobacco and indoor air pollution during pregnancy, are poorly understood, and further research and appropriate interventions are needed to test the association of these behaviours with stillbirth outcomes. For most nutritional interventions, larger randomised controlled trials are needed which report stillbirths disaggregated from composite perinatal mortality. Many antepartum stillbirths are potentially preventable in low- and middle-income countries, particularly through dietary and environmental improvement, and through improving the quality of antenatal care - particularly including diagnosis and management of high-risk pregnancies - that pregnant women receive

    Reducing stillbirths: screening and monitoring during pregnancy and labour

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    <p>Abstract</p> <p>Background</p> <p>Screening and monitoring in pregnancy are strategies used by healthcare providers to identify high-risk pregnancies so that they can provide more targeted and appropriate treatment and follow-up care, and to monitor fetal well-being in both low- and high-risk pregnancies. The use of many of these techniques is controversial and their ability to detect fetal compromise often unknown. Theoretically, appropriate management of maternal and fetal risk factors and complications that are detected in pregnancy and labour could prevent a large proportion of the world's 3.2 million estimated annual stillbirths, as well as minimise maternal and neonatal morbidity and mortality.</p> <p>Methods</p> <p>The fourth in a series of papers assessing the evidence base for prevention of stillbirths, this paper reviews available published evidence for the impact of 14 screening and monitoring interventions in pregnancy on stillbirth, including identification and management of high-risk pregnancies, advanced monitoring techniques, and monitoring of labour. Using broad and specific strategies to search PubMed and the Cochrane Library, we identified 221 relevant reviews and studies testing screening and monitoring interventions during the antenatal and intrapartum periods and reporting stillbirth or perinatal mortality as an outcome.</p> <p>Results</p> <p>We found a dearth of rigorous evidence of direct impact of any of these screening procedures and interventions on stillbirth incidence. Observational studies testing some interventions, including fetal movement monitoring and Doppler monitoring, showed some evidence of impact on stillbirths in selected high-risk populations, but require larger rigourous trials to confirm impact. Other interventions, such as amniotic fluid assessment for oligohydramnios, appear predictive of stillbirth risk, but studies are lacking which assess the impact on perinatal mortality of subsequent intervention based on test findings. Few rigorous studies of cardiotocography have reported stillbirth outcomes, but steep declines in stillbirth rates have been observed in high-income settings such as the U.S., where cardiotocography is used in conjunction with Caesarean section for fetal distress.</p> <p>Conclusion</p> <p>There are numerous research gaps and large, adequately controlled trials are still needed for most of the interventions we considered. The impact of monitoring interventions on stillbirth relies on use of effective and timely intervention should problems be detected. Numerous studies indicated that positive tests were associated with increased perinatal mortality, but while some tests had good sensitivity in detecting distress, false-positive rates were high for most tests, and questions remain about optimal timing, frequency, and implications of testing. Few studies included assessments of impact of subsequent intervention needed before recommending particular monitoring strategies as a means to decrease stillbirth incidence. In high-income countries such as the US, observational evidence suggests that widespread use of cardiotocography with Caesarean section for fetal distress has led to significant declines in stillbirth rates. Efforts to increase availability of Caesarean section in low-/middle-income countries should be coupled with intrapartum monitoring technologies where resources and provider skills permit.</p

    Reducing stillbirths: prevention and management of medical disorders and infections during pregnancy

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    Background:An estimated two-thirds of the world\u27s 3.2 million stillbirths occur antenatally, prior to labour, and are often overlooked in policy and programs. Poorly recognised, untreated or inadequately treated maternal infections such as syphilis and malaria, and maternal conditions including hypertensive disorders, are known risk factors for stillbirth. Methods: We undertook a systematic review of the evidence for 16 antenatal interventions with the potential to prevent stillbirths. We searched a range of sources including PubMed and the Cochrane Library. For interventions with prior Cochrane reviews, we conducted additional meta-analyses including eligible newer randomised controlled trials following the Cochrane protocol. We focused on interventions deliverable at the community level in low-/middle-income countries, where the burden of stillbirths is greatest. Results: Few of the studies we included reported stillbirth as an outcome, most that did were underpowered to assess this outcome. While Cochrane reviews or meta-analyses were available for many interventions, few focused on stillbirth or perinatal mortality as outcomes, and evidence was frequently conflicting. Several interventions showed clear evidence of impact on stillbirths, including heparin therapy for certain maternal indications, syphilis screening and treatment, and insecticide-treated bed nets for prevention of malaria. Other interventions, such as management of obstetric intrahepatic cholestasis, maternal anti-helminthic treatment, and intermittent preventive treatment of malaria, showed promising impact on stillbirth rates but require confirmatory studies. Several interventions reduced known risk factors for stillbirth (e.g., anti-hypertensive drugs for chronic hypertension), yet failed to show statistically significant impact on stillbirth or perinatal mortality rates. Periodontal disease emerged as a clear risk factor for stillbirth but no interventions have reduced stillbirth rates. Conclusion: Evidence for some newly recognised risk factors for stillbirth, including periodontal disease, suggests the need for large, appropriately designed randomised trials to test whether intervention can minimise these risks and prevent stillbirths. Existing evidence strongly supports infection control measures, including syphilis screening and treatment and malaria prophylaxis in endemic areas, for preventing antepartum stillbirths. These interventions should be incorporated into antenatal care programs based on attributable risks and burden of disease

    Editorial Board Composition Among Pediatric Cardiology Journals:Time to Cast the Net Wider

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    Background: No data currently exist on the diversity of editorial board members (EBMs) of pediatric cardiology journals. Objectives: The objective was to investigate the editorial boards of 5 pediatric cardiology journals to assess the composition of these boards in terms of the geographical, gender, and economic representation of their members. Methods: Information on EBMs was collected directly from 5 journal websites accessed in February 2022. The following data were collected: country of practice (including World Bank geographical and income classification), institution of practice, role on editorial board, and whether an individual held a role on 1 or more of the boards included. Results: A total of 455 EBMs were identified. A total of 369 (81%) were male. All editors-in-chief were male, and 4 were from the United States. EBMs practicing in North America accounted for 278 individuals (61%) of the editorial boards reviewed. The next majority of EBMs are practicing within Europe and Central Asia (23%, n = 103), East Asia and Pacific (7%, n = 31), Middle East and North Africa (4%, n = 18), and Latin America and Caribbean (4%, n = 16). Less than 2% (n = 9) practice in Sub-Saharan Africa and South Asia. Over 90% (n = 415) practice in high-income countries. There was no representation from low-income countries. Conclusions: Women and pediatric cardiologists practicing in countries outside of Europe and North America were underrepresented on the editorial boards of the journals studied. Diversifying composition of editorial boards may provide greater representation of underserved areas and encourage broader avenues of investigation and research

    Matematičko modeliranje u svrhu predviđanja i optimiranja zavarivačke kupke kod TIG zavarivanja

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    In this work, nonlinear and multi-objective mathematical models were developed to determine the process parameters corresponding to optimum weld pool geometry. The objectives of the developed mathematical models are to maximize tensile load (TL), penetration (P), area of penetration (AP) and/or minimize heat affected zone (HAZ), upper width (UW) and upper height (UH) depending upon the requirements.Razvijeni su nelinearni i multi-objektni matematički modeli da bi odredili parametre s optimalnom geometrijom zavarivačke kupke. Cilj razvijanja matematičkih modela je postići maksimalna vlačna čvrstoća, penetracija, područje pretaljivanja i/ili minimalna zona utjecaja topline, širina i nadvišenje zavara ovisno o postavljenim zahtjevima

    Promoting Independence in Dementia (PRIDE): A Feasibility Randomized Controlled Trial

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    Background: There is a need for interventions to foster and maintain independence for people with dementia to support community living, improve morale, and reduce stigma. We investigated a social intervention to promote living well and enhance independence for people with mild dementia.Methods: In this two arm parallel group, feasibility RCT at six sites in England, participants were randomized (1:1) to the PRIDE intervention (encompassing social, physical, and cognitive domains supported by a facilitator over three sessions) compared to usual care only. The main objective was to determine the feasibility of a main trial with respect to measures of recruitment, retention, and adherence to the intervention.Results: During a 7-month period, 402 people were invited to the trial, 148 were screened (37%, 95% confidence interval (CI)=32– 42%), 137 were eligible at pre-consent, 94 consented to the trial (69% of those eligible, 95% CI=60– 76%), and 92 were randomized (46 to each group). Of those allocated to the intervention, 42 (91%) received at least one of three intervention sessions. Outcome assessment follow-up visits were completed for 73 participants at 6 months (79%, 95% CI=70– 87%), and this was similar for both groups.Conclusion: A large multi-center trial of the PRIDE intervention in community-dwelling people with mild dementia is feasible using systematic recruitment strategies. The intervention was successfully delivered and well received by participants. Findings from this study will be used to refine the design and processes for a definitive RCT.Trial Registration: ISRCTN, ISRCTN11288961, registered on 23 October 2018
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