Dual-fuelling in compression–ignition (CI) engines is a mode of combustion where a small pilot injection of high-cetane fuel (i.e. diesel) ignites a premixed high-octane fuel (i.e. methane) and air ...mixture. This allows conventional CI engines to lower their emissions of smoke and nitrogen oxides
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while maintaining their high thermal efficiencies. However, poor ignitability of the main fuel–air charge results in increased emissions of unburnt hydrocarbons (HC) and carbon monoxide (CO). Conventional pilot fuels such as diesel and biodiesel (methyl esters transesterified from raw plant oil) have been researched extensively in prior work, showing that in terms of performance and emissions they perform fairly similarly. This is because the physical, chemical and combustion properties of various methyl esters are comparable to those of conventional diesel. In order to reduce these emissions of HC and CO, alternative pilot fuels need to be considered. As fuels employed during normal CI engine operation, both dimethyl ether (DME, a gaseous CI engine fuel) and water-in-fuel emulsions (conventional biodiesel mixed with varying concentrations of water) have shown that they reduce smoke and
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emissions significantly, while improving combustion quality. In this work, the performance of DME and water-in-biodiesel emulsions as pilot fuels was assessed. It was seen that the water-in-biodiesel emulsions did not perform as well as expected, as increased HC and CO emissions coupled with a mild change in
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levels was encountered (compared to conventional pilot fuel, in this case neat biodiesel). The emulsions performed very poorly as pilot fuels below a certain BMEP threshold. DME, while producing higher levels of HC and CO than neat biodiesel, managed to reduce
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significantly compared to neat biodiesel. Emissions of HC and CO, while higher than neat biodiesel, were not as high as levels seen with the emulsions. Thermal efficiency levels were generally maintained with the liquid pilot fuels, with the DME pilot producing comparatively lower levels.
The twin challenges of fossil fuel depletion and environmental degradation, present engine and vehicle manufacturers with problems focused on future provision of both automotive power plant and ...conventional hydrocarbon fuels. In the drive to meet more stringent emission controls, many options have been identified, in the investigation of viable alternative fuels, and in the means of meeting the standards. While the operation of spark-ignition engines with natural gas is proven, other fuels are currently being explored for compression-ignition engines. In this study, di-methyl ether and rape-seed methyl ester, together with diesel fuel, were used, both as neat fuels and for pilot injection, in a natural gas dual-fuelled compression-ignition engine, to examine the performance and the levels of exhaust emissions. The merits and shortcomings as alternative fuels for diesel engines are discussed. While the ester performs much like diesel fuel in both modes, the ether produced lower specific oxides of nitrogen in dual-fuel operation.
The prediction of capsize of small high-speed craft is highly complex. In this paper, risk analysis is applied to predict the probability of capsize of two types of high-speed craft due to dangerous ...wave events in the estuary of the Bonny River in the Niger Delta region of Nigeria. Fibreglass reinforced plastic (FRP) hull craft, widely used for transportation, were considered for the prediction. The probability of the craft encountering a dangerous wave situation at a random position at sea and the probability of capsize were calculated using published wave statistics and computer-based analytical models. Results obtained compared favourably with similar analyses carried out by previous investigators for other regions. Various rational and practical ways of reducing the probability of capsize to an acceptable level are presented. From the prediction it was established that human error was a predominant factor in the capsize of vessels.
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by heterogeneous cognitive, behavioral and communication impairments. Disruption of the gut-brain axis (GBA) has been ...implicated in ASD although with limited reproducibility across studies. In this study, we developed a Bayesian differential ranking algorithm to identify ASD-associated molecular and taxa profiles across 10 cross-sectional microbiome datasets and 15 other datasets, including dietary patterns, metabolomics, cytokine profiles and human brain gene expression profiles. We found a functional architecture along the GBA that correlates with heterogeneity of ASD phenotypes, and it is characterized by ASD-associated amino acid, carbohydrate and lipid profiles predominantly encoded by microbial species in the genera Prevotella, Bifidobacterium, Desulfovibrio and Bacteroides and correlates with brain gene expression changes, restrictive dietary patterns and pro-inflammatory cytokine profiles. The functional architecture revealed in age-matched and sex-matched cohorts is not present in sibling-matched cohorts. We also show a strong association between temporal changes in microbiome composition and ASD phenotypes. In summary, we propose a framework to leverage multi-omic datasets from well-defined cohorts and investigate how the GBA influences ASD.
Objectives
In the current study, the Anderson model is used to determine equitable access to dementia care in Europe. Predisposing, enabling, and need variables were investigated to find out whether ...there is equitable access to dementia‐specific formal care services. Results can identify which specific factors should be a target to improve access.
Methods
A total of 451 People with middle‐stage dementia and their informal carers from eight European countries were included. At baseline, there was no use of formal care yet, but people were expected to start using formal care within the next year. Logistic regressions were carried out with one of four clusters of service use as dependent variables (home social care, home personal care, day care, admission). The independent variables (predisposing, enabling, and need variables) were added to the regression in blocks.
Results
The most significant predictors for the different care clusters are disease severity, a higher sum of (un)met needs, hours spent on informal care, living alone, age, region of residence, and gender.
Conclusion
The Andersen model provided for this cohort the insight that (besides need factors) the predisposing variables region of residence, gender, and age do play a role in finding access to care. In addition, it showed us that the numbers of hours spent on informal care, living alone, needs, and disease severity are also important predictors within the model's framework. Health care professionals should pay attention to these predisposing factors to ensure that they do not become barriers for those in need for care.
Purpose
Informal care constitutes an important part of the total care for people with dementia. Therefore, the impact of the syndrome on their caregivers as well as that of health and social care ...services for people with dementia should be considered. This study investigated the convergent and clinical validity of the CarerQol instrument, which measures and values the impact of providing informal care, in a multi-country sample of caregivers for people with dementia.
Methods
Cross-sectional data from a sample of 451 respondents in eight European countries, collected by the Actifcare project, were evaluated. Convergent validity was analysed with Spearman’s correlation coefficients and multivariate correlations between the CarerQol-7D utility score and dimension scores, and other similar quality of life measures such as CarerQol-VAS, ICECAP-O, and EQ-5D. Clinical validity was evaluated by bivariate and multivariate analyses of the degree to which the CarerQol instrument can differentiate between characteristics of caregivers, care receivers and caregiving situation. Country dummies were added to test CarerQol score differences between countries.
Results
The mean CarerQol utility score was 77.6 and varied across countries from 74.3 (Italy) to 82.3 (Norway). The scores showed moderate to strong positive correlations with the CarerQol-VAS, ICECAP-O, and EQ-5D health problems score of the caregiver. Multivariate regression analysis showed that various characteristics of the caregiver, care receiver and caregiving situation were associated with caregiver outcomes, but there was no evidence of a country-level effect.
Conclusion
This study demonstrates the convergent and clinical validity of the CarerQol instrument to evaluate the impact of providing informal care for people with dementia.
To examine prospectively the association between unmet needs for daytime activities and company and behavioural and psychological symptoms of dementia.
We included 451 people with mild or moderate ...dementia, from eight European countries, who were assessed three times over 12 months. Unmet needs were measured with the Camberwell Assessment of Need for the Elderly. Three sub-syndromes of the Neuropsychiatric Inventory-Questionnaire were regressed, one-by-one, against unmet needs for daytime activities and company, adjusting for demographic and clinical-functional covariates.
Unmet needs for daytime activities were associated with more affective symptoms at baseline, six and twelve months, mean 0.74 (p < 0.001), 0.76 (p < 0.001) and 0.78 (p = 0.001) points higher score respectively, and with more psychotic symptoms at baseline (mean 0.39 points, p = 0.007) and at six months follow-up (mean 0.31 points, p = 0.006). Unmet needs for company were associated with more affective symptoms at baseline, six and twelve months, mean 0.44 (p = 0.033), 0.67 (p < 0.001) and 0.91 (p < 0.001) points higher score respectively, and with more psychotic symptoms at baseline (mean 0.40 points, p = 0.005) and at six months (mean 0.35 points, p = 0.002) follow-up.
Interventions to reduce unmet needs for daytime activities and company could reduce affective and psychotic symptoms in people with dementia.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
This paper reports on qualitative data from the Actifcare study investigating experiences, attitudes, barriers and facilitators concerning access to and use of formal care. A total of 85 ...semi‐structured in‐depth interviews were conducted in eight European countries. Results were analysed with a deductive content analysis, first within country and then integrated in a cross‐national analysis. Overall, analysis of the in‐depth interviews revealed two major themes with five subcategories. The results can be summarised in an optimal pathway for access to dementia care. This pathway includes fixed factors such as disease‐related factors and system‐related factors. In addition there are personal factors that are subject to change such as attitudes towards care. An important finding consisted of the necessity of having sufficient information about the disease and available care and having a key contact person to guide you through the process of finding suitable care while monitoring your needs. In addition, it is important to involve your social network as they can take on care‐giving tasks. It is helpful to have a diagnosis (in most countries). Concerning decision‐making, the person closest to the person with dementia is in the majority of cases the one who makes the ultimate decision to access and use services and he/she should therefore be supported in this process. These results provide insight into the factors that influence the pathway to formal care use and help professionals to enhance access to formal dementia care by focusing on factors that can be modified.
Home-dwelling people with dementia and their informal carers experience barriers impeding access to community care services. This study is a part of the Actifcare project where eight countries ...participated. The aim was to achieve consensus on best practice recommendations for enhancing access to and use of formal community care services.
A Delphi consensus process was conducted. A total of 48 professional experts, 14 people with dementia and 20 informal carers rated the importance of 72 statements on a 7-point Likert scale. Consensus was based on the median and level of dispersion.
Sixty-two statements reached consensus, resulting in three categories of recommendations. An appointed contact person was central in Recommendations to enhance access. Coordination and flexibility in setting and type of services were among the Recommendations to enhance use. Training of health care personnel and person-centred care were central Recommendations that can facilitate access or use indirectly.
The Actifcare Best Practice Recommendations suggest practical measures that can be taken by decision makers to enhance access and use of community care services, and thereby enhance quality of care and quality of life for home dwelling people with dementia and their informal carers.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Relationship quality (RQ) between a person with dementia and a family carer may influence their health and quality of life. However, evidence regarding its course and influencing factors is limited. ...We aimed to explore RQ trajectories in dementia, and identify predictors of change.
We analysed longitudinal data from a cohort of 350 community-dwelling people with dementia and their informal carers, participating in the Actifcare study in eight European countries. The Positive Affect Index, rated separately by both people with dementia and their carers, assessed RQ. Other measures included the Neuropsychiatric Inventory Questionnaire (regarding persons with dementia), and the Relative Stress Scale, Sense of Coherence Scale and Lubben Social Network Scale (for carers). Trajectories and influencing factors were explored applying a latent growth model (LGM).
RQ in the group of carers declined over 1 year, but RQ scores for the persons with dementia did not change. Higher stress in carers negatively influenced their baseline RQ ratings. Carer sense of coherence and being a spouse were associated with more positive baseline RQ carer assessments. Higher levels of neuropsychiatric symptoms were linked to decline in carers' RQ, whereas social support was associated with more positive RQ trajectories.
This study provides a valuable insight into the course of RQ. LGM proved useful to explore the factors that influence RQ trajectories and variability within- and between-persons. Our findings emphasise the importance of carer-perceived social support and sense of coherence, and of reducing neuropsychiatric symptoms, in maintaining a good RQ.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
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