218 research outputs found
Small molecule dopant-free dual hole transporting material for conventional and inverted perovskite solar cells
Interfacial layers play very important roles in perovskite solar cells and the enormous diversity of reported materials has contributed to the outstanding progress of these photovoltaic devices. Nevertheless, the interfacial materials are commonly developed to be used in solar cells with a specific architecture, either conventional (n-i-p) or inverted (p-i-n). We report the exceptional performance of a small molecule, whose structural features, based on hydrogen bond-directed self-assembly, allow its application as hole transporting layer (HTL) in n-i-p and p-i-n perovskite solar cells with the same efficiency. This particularity has been investigated through a comparative study with a very similar molecule that cannot self-assemble, evidencing the benefits of the structural integrity of hydrogen bonded HTLs in terms of charge extraction and recombination, independently on the device architecture.</p
COVID-19: guidance on palliative care from a European Respiratory Society international task force
Copyright ©ERS 2020. BACKGROUND: Many people are dying from coronavirus disease 2019 (COVID-19), but consensus guidance on palliative care in COVID-19 is lacking. This new life-threatening disease has put healthcare systems under pressure, with the increased need of palliative care provided to many patients by clinicians who have limited prior experience in this field. Therefore, we aimed to make consensus recommendations for palliative care for patients with COVID-19 using the Convergence of Opinion on Recommendations and Evidence (CORE) process. METHODS: We invited 90 international experts to complete an online survey including stating their agreement, or not, with 14 potential recommendations. At least 70% agreement on directionality was needed to provide consensus recommendations. If consensus was not achieved on the first round, a second round was conducted. RESULTS: 68 (75.6%) experts responded in the first round. Most participants were experts in palliative care, respiratory medicine or critical care medicine. In the first round, consensus was achieved on 13 recommendations based upon indirect evidence and clinical experience. In the second round, 58 (85.3%) out of 68 of the first-round experts responded, resulting in consensus for the 14th recommendation. CONCLUSION: This multi-national task force provides consensus recommendations for palliative care for patients with COVID-19 concerning: advance care planning; (pharmacological) palliative treatment of breathlessness; clinician-patient communication; remote clinician-family communication; palliative care involvement in patients with serious COVID-19; spiritual care; psychosocial care; and bereavement care. Future studies are needed to generate empirical evidence for these recommendations
Multi-disciplinary palliative care is effective in people with symptomatic heart failure: A systematic review and narrative synthesis
Background: Despite recommendations, people with heart failure have poor access to palliative care. Aim: To identify the evidence in relation to palliative care for people with symptomatic heart failure. Design: Systematic review and narrative synthesis. (PROSPERO CRD42016029911) Data sources: Databases (Medline, Cochrane database, CINAHL, PsycINFO, HMIC, CareSearch Grey Literature), reference lists and citations were searched and experts contacted. Two independent reviewers screened titles and abstracts and retrieved papers against inclusion criteria. Data were extracted from included papers and studies were critically assessed using a risk of bias tool according to design. Results: Thirteen interventional and 10 observational studies were included. Studies were heterogeneous in terms of population, intervention, comparator, outcomes and design rendering combination inappropriate. The evaluation phase studies, with lower risk of bias, using a multi-disciplinary specialist palliative care intervention showed statistically significant benefit for patient-reported outcomes (symptom burden, depression, functional status, quality of life), resource use and costs of care. Benefit was not seen in studies with a single component/discipline intervention or with higher risk of bias. Possible contamination in some studies may have caused under-estimation of effect and missing data may have introduced bias. There was no apparent effect on survival. Conclusion: Overall, the results support the use of multi-disciplinary palliative care in people with advanced heart failure but trials do not identify who would benefit most from specialist palliative referral. There are no sufficiently robust multi-centre evaluation phase trials to provide generalisable findings. Use of common population, intervention and outcomes in future research would allow meta-analysis
Adjusting aggregation modes and photophysical and photovoltaic properties of diketopyrrolopyrrole-based small molecules by introducing BâN bonds
The packing mode of small-molecular semiconductors in thin films is an important factor that controls the performance of their optoelectronic devices. Designing and changing the packing mode by molecular engineering is challenging. Three structurally related diketopyrrolopyrrole (DPP)-based compounds were synthesized to study the effect of replacing CâC bonds by isoelectronic dipolar BâN bonds. By replacing one of the bridging CâC bonds on the peripheral fluorene units of the DPP molecules by a coordinative BâN bond and changing the BâN bond orientation, the optical absorption, fluorescence, and excited-state lifetime of the compounds can be tuned. The substitution alters the preferential aggregation of the molecules in the solid state from H-type (for CâC) to J-type (for BâN). Introducing BâN bonds thus provides a subtle way of controlling the packing mode. The photovoltaic properties of the compounds were evaluated in bulk heterojunctions with a fullerene acceptor and showed moderate performance as a consequence of suboptimal morphologies, bimolecular recombination, and triplet-state formation
Clustering of 27,525,663 death records from the United States based on health conditions associated with death: an example of big health data exploration
Background: Insight into health conditions associated with death can inform healthcare policy. We aimed to cluster 27,525,663 deceased people based on the health conditions associated with death to study the associations between the health condition clusters, demographics, the recorded underlying cause and place of death. Methods: Data from all deaths in the United States registered between 2006 and 2016 from the National Vital Statistics System of the National Center for Health Statistics were analyzed. A self-organizing map (SOM) was used to create an ordered representation of the mortality data. Results: 16 clusters based on the health conditions associated with death were found showing significant differences in socio-demographics, place, and cause of death. Most people died at old age (73.1 (18.0) years) and had multiple health conditions. Chronic ischemic heart disease was the main cause of death. Most people died in the hospital or at home. Conclusions: The prevalence of multiple health conditions at death requires a shift from disease-oriented towards person-centred palliative care at the end of life, including timely advance care planning. Understanding differences in population-based patterns and clusters of end-of-life experiences is an important step toward developing a strategy for implementing population-based palliative care
Respiratory adverse effects of opioids for breathlessness: a systematic review and meta-analysis
Background: Previous studies have shown that opioids can reduce chronic breathlessness in advanced disease. However, physicians remain reluctant to prescribe opioids for these patients, commonly due to fear of respiratory adverse effects. Aim: To systematically review reported respiratory adverse effects of opioids in patients with advanced disease and chronic breathlessness. Methods: Pubmed, Embase, Cochrane central register of controlled trials, CINAHL, ClinicalTrials.gov and the reference lists of relevant systematic reviews were searched. Two independent researchers screened against predefined inclusion criteria and extracted data. Meta-analysis was conducted where possible. Results: We included 63 out of 1990 articles, describing 67 studies. Meta-analysis showed an increase in partial pressure of carbon dioxide (0.27 kPa; 95% CI 0.08 to 0.45) and no significant change in partial pressure of oxygen and oxygen saturation (both p>0.05). Non-serious respiratory depression (definition variable/not stated) was described in 4/1064 patients. One cancer patient pre-treated with morphine for pain needed temporary respiratory support following nebulized morphine for breathlessness (single case study). Conclusions: We found no evidence of significant or clinically relevant respiratory adverse effects of opioids for chronic breathlessness. Heterogeneity of design and study population, and low study quality are limitations. Larger studies designed to detect respiratory adverse effects are needed
Determinants of the Proinflammatory Action of Ambient Particulate Matter in Immortalized Murine Macrophages
Background: Proximity to traffic-related pollution has been associated with poor respiratory health in adults and children. Objectives: We wished to test the hypothesis that particulate matter (PM) from high-traffic sites would display an enhanced capacity to elicit inflammation. Methods: We examined the inflammatory potential of coarse [2.5â10 ÎŒm in aerodynamic diameter (PM2.5â10)] and fine [0.1â2.5 ÎŒm in aerodynamic diameter (PM0.1â2.5)] PM collected from nine sites throughout Europe with contrasting traffic contributions. We incubated murine monocytic-macrophagic RAW264.7 cells with PM samples from these sites (20 or 60 ÎŒg/cm2) and quantified their capacity to stimulate the release of arachidonic acid (AA) or the production of interleukin-6 and tumor necrosis factor-α (TNFα) as measures of their inflammatory potential. Responses were then related to PM composition: metals, hydrocarbons, anions/cations, and endotoxin content. Results: Inflammatory responses to ambient PM varied markedly on an equal mass basis, with PM2.5â10 displaying the largest signals and contrasts among sites. Notably, we found no evidence of enhanced inflammatory potential at high-traffic sites and observed some of the largest responses at sites distant from traffic. Correlation analyses indicated that much of the sample-to-sample contrast in the proinflammatory response was related to the content of endotoxin and transition metals (especially iron and copper) in PM2.5â10. Use of the metal chelator diethylene triamine pentaacetic acid inhibited AA release, whereas recombinant endotoxin-neutralizing protein partially inhibited TNFα production, demonstrating that different PM components triggered inflammatory responses through separate pathways. Conclusions: We found no evidence that PM collected from sites in close proximity to traffic sources displayed enhanced proinflammatory activity in RAW264.7 cells. Key words: copper, endotoxin, inflammation, iron, macrophages, metals, particulate matter, polyaromatic hydrocarbons. Environ Health Perspect 118:1728â1734 (2010). doi:10.1289/ehp.1002105 [Online 27 July 2010
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