The field dependence and yield of free charge carrier generation in polymer:fullerene blends with varying energetic offsets is not affected when the excitation energy is varied from above band‐gap to ...direct CT state excitation. Instead, the ability of the CT state to split is dictated by the energetic offset between the relaxed CT state and the charge separated (CS) state.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This study describes the impact of a single fluorine atom substitution in the conjugated backbone of poly(cyclopentadithiophene-alt-benzothiadiazole) on the structure and the polymorphism of ...the polymer bearing 2-ethylhexyl side chains. Controlled growth of the nonfluorinated and fluorinated polymers by solvent vapor annealing (SVA), melt-crystallization on oriented poly(tetrafluoroethylene), and high-temperature rubbing yield highly crystalline and/or oriented films of a thermodynamically stable polymorph called form I. The single-crystal hk0 and the oriented fiber patterns are obtained in films prepared by SVA and aligned films, respectively. Form I involves a high-symmetry packing of four chains in an orthorhombic cell (Pccn space group) with pseudohexagonal symmetry. The chains are paired into dimers with a 3.6–3.8 Å interchain π-stacking distance and a segregated mode of stacking of cyclopentadithiophene and benzothiadiazole (BT). A single H/F substitution on the BT unit modifies the orientation of the dimers in the unit cell of form I. Absorption and structural properties of this new polymorph are discussed with respect to the classical π-stacking structure obtained from solvent-additive processed films. Evidence of yet another polymorph (form II) highlights the polymorphism of these alternated donor–acceptor copolymers.
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IJS, KILJ, NUK, PNG, UL, UM
The nanomorphology of the high mobility polymer poly{N,N′‐bis(2‐octyldodecyl)‐1,4,5,8‐naphthalenedicarboximide‐2,6‐diyl‐alt‐5,5′‐(2,2′‐bithiophene)} P(NDI2OD‐T2) in thin films is explored as a ...function of different annealing conditions and correlated to optical and electrical properties. While nanofibrils with face‐on orientation in form I are obtained directly after spin‐coating and annealing below the melt transition temperature, clear evidence of lamellar structures is found after melt‐annealing followed by slow cooling to room temperature. Interestingly these structural changes are accompanied by distinct changes in the absorption patterns. Electron diffraction measurements further show clear transitions towards predominant edge‐on oriented chains in form II upon melt‐annealing. Large‐scale alignment with dichroic ratios up to 10 and improved order is achieved by high temperature rubbing and subsequent post‐rubbing annealing. These highly oriented morphologies allow anisotropic in‐plane charge transport to be probed with top‐gate transistors parallel and perpendicular to the polymer chain direction. Mobilities up to 0.1 cm2 V‐1 s‐1 are observed parallel to the polymer chain, which is up to 10 times higher than those perpendicular to the polymer chain.
Large‐scale alignment of a high mobility, n‐type donor–acceptor polymer is achieved by high temperature rubbing of thin films, while post‐rubbing thermal annealing protocols strongly dictate the texture. These highly ordered and oriented layers exhibit anisotropic charge transport with enhanced electron mobilities along the polymer backbone as compared to the perpendicular direction.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Currently, social and political discussions are dominated by aspects related to the handling of the COVID-19 pandemic. Several approaches for supporting science in times of COVID-19 have been ...undertaken at the national and supranational level, such as the COVID-19 recovery fund by the European Union. For reducing the global disease burden and the societal burden related to economic crises caused by the COVID-19 pandemic, adequate political and financial support is needed. This is closely related to funding of research and programs for absorbing the adverse effects of the pandemic and the measures introduced to diminish the spread of the disease. This contribution highlights the relevance of public health research and international health diplomacy to evaluate the direct and indirect impacts of COVID-19 on populations health.
•Research funding needs to be spent foresighted and coordinated.•Internationally coordinated approaches and collaborations are needed.•Evaluation of funds is necessary.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Research indicates that clinical guidelines are often not applied. The success of their implementation depends on the consideration of a variety of barriers and the use of adequate strategies to ...overcome them. Therefore, this scoping review aims to describe and categorize the most important barriers to guideline implementation. Furthermore, it provides an overview of different kinds of suitable strategies that are tailored to overcome these barriers. The search algorithm led to the identification of 1659 articles in PubMed. Overall, 69 articles were included in the data synthesis. The content of these articles was analysed by using a qualitative synthesis approach, to extract the most important information on barriers and strategies. The barriers to guideline implementation can be differentiated into personal factors, guideline-related factors, and external factors. The scoping review revealed the following aspects as central elements of successful strategies for guideline implementation: dissemination, education and training, social interaction, decision support systems and standing orders. Available evidence indicates that a structured implementation can improve adherence to guidelines. Therefore, the barriers to guideline implementation and adherence need to be analysed in advance so that strategies that are tailored to the specific setting and target groups can be developed.
Zusammenfassung
Digitale Technologien sind in nahezu alle Lebensbereiche diffundiert und somit zu einem ständigen Begleiter unseres Alltags geworden. Digitalen Interventionen werden auch Potenziale ...in der Prävention und Gesundheitsförderung zugeschrieben. Bislang mangelt es aber an fundierten Belegen zur Wirksamkeit entsprechender Maßnahmen. In diesem Beitrag sollen die Herausforderungen der Evidenzbasierung von digitalen Interventionen in der Prävention und Gesundheitsförderung aufgezeigt werden. Die Ergebnisse werden in Form eines narrativen Übersichtsbeitrags zusammengefasst.
Bislang wurden Methoden der evidenzbasierten Medizin bei der Bewertung des Nutzens und Schadens im Bereich von Prävention und Gesundheitsförderung nicht oder nur bedingt eingesetzt. Gründe dafür liegen in der Komplexität entsprechender Maßnahmen. Diese Komplexität wird bei digitalen Interventionen nochmals erhöht. Dennoch wird dringend angeraten, einen stärkeren Fokus auf die Evidenzbasierung zu legen, um aussagekräftige und nachvollziehbare Bewertungsverfahren hinsichtlich der Wirksamkeit digitaler Interventionen in Prävention und Gesundheitsförderung zu ermöglichen.
Die Digitalisierung führt zu neuen Anforderungen an Prävention und Gesundheitsförderung. Es bedarf einer kritischen Perspektive auf die tatsächlichen Wirkpotenziale digitaler Interventionen sowie deren gesellschaftliche Implikationen. Der Aufbau einer soliden Wissensbasis ist notwendig, um Akzeptanz gegenüber den Technologien zu fördern und eine nachhaltige Etablierung zu erreichen.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Higher general intelligence attenuates age-associated cognitive decline and the risk of dementia. Thus, intelligence has been associated with cognitive reserve or resilience in normal aging. ...Neurophysiologically, intelligence is considered as a complex capacity that is dependent on a global cognitive network rather than isolated brain areas. An association of structural as well as functional brain network characteristics with intelligence has already been reported in young adults. We investigated the relationship between global structural brain network properties, general intelligence and age in a group of 43 cognitively healthy elderly, age 60-85 years. Individuals were assessed cross-sectionally using Wechsler Adult Intelligence Scale-Revised (WAIS-R) and diffusion-tensor imaging. Structural brain networks were reconstructed individually using deterministic tractography, global network properties (global efficiency, mean shortest path length, and clustering coefficient) were determined by graph theory and correlated to intelligence scores within both age groups. Network properties were significantly correlated to age, whereas no significant correlation to WAIS-R was observed. However, in a subgroup of 15 individuals aged 75 and above, the network properties were significantly correlated to WAIS-R. Our findings suggest that general intelligence and global properties of structural brain networks may not be generally associated in cognitively healthy elderly. However, we provide first evidence of an association between global structural brain network properties and general intelligence in advanced elderly. Intelligence might be affected by age-associated network deterioration only if a certain threshold of structural degeneration is exceeded. Thus, age-associated brain structural changes seem to be partially compensated by the network and the range of this compensation might be a surrogate of cognitive reserve or brain resilience.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Globally, increasing rates of obesity are one of the most important health issues. The association between breakfast skipping and body weight is contradictory between cross-sectional and ...interventional studies. This systematic review and meta-analysis aims to summarize this association based on observational longitudinal studies. We included prospective studies on breakfast skipping and overweight/obesity or weight change in adults. The literature was searched until September 2020 in PubMed and Web of Science. Summary risk ratios (RRs) or β coefficients with a 95% confidence interval (CI), respectively, were estimated in pairwise meta-analyses by applying a random-effects model. In total, nine studies were included in the systematic review and five of them were included in the meta-analyses. The meta-analyses indicated an 11% increased RR for overweight/obesity when breakfast was skipped on ≥3 days per week compared to ≤2 days per week (95% CI: 1.04, 1.19,
= two studies). The meta-analysis on body mass index (BMI) change displayed no difference between breakfast skipping and eating (β = -0.02; 95% CI: -0.05, 0.01;
= two studies). This study provides minimal evidence that breakfast skipping might lead to weight gain and the onset of overweight and obesity.
There are basically four options to which state the limiting instant in a change from one state to its opposite belongs – only the first, only the second, both or none. This situation is usually ...referred to as the limit decision problem since all of these options seem troublesome: The first two alleged solutions are asymmetric and thus need something to ground this asymmetry in (a symmetry-breaker); while the last two options leave the realm of classical logic. I argue that including the debate about dispositions enables new options for solutions to the temporal limit decision problem. Metaphysical considerations function as a symmetry-breaker and thus remove the need for a non-classical solution. Dispositions bring about the changes in the world, so they constitute the metaphysical background for the instant of change. In particular, I argue that according to the triadic process account of dispositions, the limiting instant belongs to the second interval and only the second interval.
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