Polysaccharide-based aerogels provide high added-value lightweight materials with outstanding surface area and open porosity, susceptible to be loaded with active compounds in pharmaceutical ...applications. Aerogels are obtained by coupling sol–gel processing to a suitable drying technology, usually supercritical drying. The size and morphology of aerogels can be customized by means of the choice of the proper processing technology. Display omitted
► State-of-the-art of polysaccharide aerogels for pharmaceutical uses are described. ► Aerogel technology provides highly porous, high surface area, lightweight carriers. ► Biodegradable and biocompatible carriers with high drug loading capacity are obtained. ► Processing parameters strongly influence the resulting end material properties. ► Case studies on polysaccharide aerogels and their use in drug delivery are described.
Polysaccharides are regarded as key ingredients for the production of bio-based materials in life sciences (e.g., food, cosmetics, medical devices, pharmaceutics). The biodegradability and biocompatibility of these biopolymers, coupled to the large variety of chemical functionalities they encompass, make them promising carriers for drug delivery systems. Aerogels are a special class of nanoporous materials with growing interest in biomedical and pharmaceutical applications due to their open pore structure and high surface area. Polysaccharide-based aerogels result in highly porous (ɛ=90–99%), lightweight (ρ=0.07–0.46g/cm3) drug carriers with high surface area (Sa=70–680m2/g), able to provide enhanced drug bioavailability and drug loading capacity. This review focuses on the state-of-the-art of the production of polysaccharide-based aerogels with emphasis on the influence of processing parameters on the resulting end material properties. Case studies on polysaccharide-based aerogels from several sources and own results as well as their behavior regarding drug loading capacity and release are described.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract
In this paper, we describe the routine photometric calibration of data taken with the VISTA infrared camera (VIRCAM) instrument on the ESO Visible and Infrared Survey Telescope for Astronomy ...(VISTA) telescope. The broad-band ZYJHKs data are directly calibrated from Two Micron all Sky Survey (2MASS) point sources visible in every VISTA image. We present the empirical transformations between the 2MASS and VISTA, and Wide-Field Camera and VISTA, photometric systems for regions of low reddening. We investigate the long-term performance of VISTA+VIRCAM. An investigation of the dependence of the photometric calibration on interstellar reddening leads to these conclusions: (1) For all broad-band filters, a linear colour-dependent correction compensates the gross effects of reddening where E(B − V) < 5.0. (2) For Z and Y, there is a significantly larger scatter above E(B − V) = 5.0, and insufficient measurements to adequately constrain the relation beyond this value. (3) The JHKs filters can be corrected to a few per cent up to E(B − V) = 10.0. We analyse spatial systematics over month-long time-scales, both inter- and intradetector and show that these are present only at very low levels in VISTA. We monitor and remove residual detector-to-detector offsets. We compare the calibration of the main pipeline products: pawprints and tiles. We show how variable seeing and transparency affect the final calibration accuracy of VISTA tiles, and discuss a technique, grouting, for mitigating these effects. Comparison between repeated reference fields is used to demonstrate that the VISTA photometry is precise to better than ≃ 2 per cent for the YJHKs bands and 3 per cent for the Z bands. Finally, we present empirically determined offsets to transform VISTA magnitudes into a true Vega system.
Social groups are fundamental building blocks of human societies. While our social interactions have always been constrained by geography, it has been impossible, due to practical difficulties, to ...evaluate the nature of this restriction on social group structure. We construct a social network of individuals whose most frequent geographical locations are also known. We also classify the individuals into groups according to a community detection algorithm. We study the variation of geographical span for social groups of varying sizes, and explore the relationship between topological positions and geographic positions of their members. We find that small social groups are geographically very tight, but become much more clumped when the group size exceeds about 30 members. Also, we find no correlation between the topological positions and geographic positions of individuals within network communities. These results suggest that spreading processes face distinct structural and spatial constraints.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Introduced in its contemporary form in 1946 (ref. 1), but with roots that go back to the eighteenth century, the gravity law is the prevailing framework with which to predict population movement, ...cargo shipping volume and inter-city phone calls, as well as bilateral trade flows between nations. Despite its widespread use, it relies on adjustable parameters that vary from region to region and suffers from known analytic inconsistencies. Here we introduce a stochastic process capturing local mobility decisions that helps us analytically derive commuting and mobility fluxes that require as input only information on the population distribution. The resulting radiation model predicts mobility patterns in good agreement with mobility and transport patterns observed in a wide range of phenomena, from long-term migration patterns to communication volume between different regions. Given its parameter-free nature, the model can be applied in areas where we lack previous mobility measurements, significantly improving the predictive accuracy of most of the phenomena affected by mobility and transport processes.
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DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•We compare batteries deployed in 4500 individual households with 200 communities.•Using real demand, PV data and locations we form community microgrids.•We find that community batteries are more ...effective for distributed PV integration.•Internal rates of return depend on the number of PV households.
Energy storage can help integrate local renewable generation, however the best deployment level for storage remains an open question. Using a data-driven approach, this paper simulates 15-min electricity consumption for households and groups them into local communities of neighbors using real locations and the road network in Cambridge, MA. We then simulate PV for these households and use this framework to study battery economics in a high PV adoption, high electricity cost scenario, in order to demonstrate significant storage adoption. We compare the results of storage adoption at the level of individual households to storage adoption on the community level using the aggregated community demands. Under the simulated conditions, we find that the optimum storage at the community level was 65% of that at the level of individual households and each kWh of community battery installed was 64–94% more effective at reducing exports from the community to the wider network. Therefore, given the current increasing rates of residential battery deployment, our research highlights the need for energy policy to develop market mechanisms which facilitate the deployment of community storage.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This research was focused on measuring the TFP bioeconomy post-Covid-19 in six regions of the world. The panel data was organized with FAO Statistics data. Linear programming with an enveloping data ...analysis (DEA) approach was used to measure the Malmquist TFP indices to determine the inter-annual productivity and technical efficiency changes by region. The results show that the effect of Covid-19 on the bioeconomy productivity during the period 2012-2021 on average decreased by 11.6%. This effect was explained by the decomposition of the productivity change into the changes in technical efficiency. The workers decreased their efficiency by 11.7%. In the Northern American region, it decreased by 21.6%, in the Southern European region by 10.1, and in Western Europe by 11.7%. The results show a downward trend that was affected in the year 2019 by Covid-19, however, it was possible to recover in the following year. One of the conclusions of these results is the effect of the immediate strategies that the governments of the region implemented. This effect was a little slower in the North American, Southeastern, and Eastern European regions. Finally, it is concluded that the measures implemented by the governments in the studied regions had an increasing effect in conditions of variable scale returns. In other words, the companies that remained on a constant scale decreased.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
BACKGROUND: In Cuba, the first cases of coronavirus 2019 (COVID-19) were confirmed on March 11, 2020, when the World Health Organization (WHO) officially declared the pandemic and the Ministry of ...Public Health of Cuba (MINSAP) began to execute the COVID-19 Prevention and Control Plan. This plan was prepared two months earlier by MINSAP working together with the National Civil Defense and the government approved it at the end of January. OBJECTIVE: The aim of this research is to assess the effectiveness of the government strategies to deal with COVID-19, by analyzing the role of the different agencies involved in the pandemic management. METHODS: A bibliographical review of the following documents was conducted: information issued by MINSAP and other ministries, archives of the Pedro Kouri Institute (IPK) and Cuban journals regarding the high impact in the field of medicine. The data were processed with different tools (diagrams, bar graphs, analysis and synthesis, etc.) that allowed measuring the effectiveness of the strategies implemented. RESULTS: The government’s strategies focused on: the integration of all state agencies and some private institutions to confront COVID-19; the collaboration between MINSAP specialists, country’s research centers and universities for the creation of vaccines to contain the pandemic; the production of medical equipment and instruments; the design of the organization processes of the services, such as planning techniques and distribution of ambulances, allocation of hospitals and isolation centers for sufferers and direct contacts respectively. CONCLUSION: The analysis carried out showed that the interrelations between the different organizations involved had positive influences on the treatment of the pandemic.
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IZUM, KILJ, NUK, OILJ, PILJ, SAZU, UL, UM, UPUK, VSZLJ
Context. Transition disks offer the extraordinary opportunity to look for newly born planets and to investigate the early stages of planet formation. Aim. In this context we observed the Herbig A5 ...star MWC 758 with the L′-band vector vortex coronagraph installed in the near-infrared camera and spectrograph NIRC2 at the Keck II telescope, with the aim of unveiling the nature of the spiral structure by constraining the presence of planetary companions in the system. Methods. Our high-contrast imaging observations show a bright (ΔL′ = 7.0 ± 0.3 mag) point-like emission south of MWC 758 at a deprojected separation of ~20 au (r = 0.′′111 ± 0.′′004) from the central star. We also recover the two spiral arms (southeast and northwest), already imaged by previous studies in polarized light, and discover a third arm to the southwest of the star. No additional companions were detected in the system down to 5 Jupiter masses beyond 0.′′6 from the star. Results. We propose that the bright L′-band emission could be caused by the presence of an embedded and accreting protoplanet, although the possibility of it being an asymmetric disk feature cannot be excluded. The spiral structure is probably not related to the protoplanet candidate, unless on an inclined and eccentric orbit, and it could be due to one (or more) yet undetected planetary companions at the edge of or outside the spiral pattern. Future observations and additional simulations will be needed to shed light on the true nature of the point-like source and its link with the spiral arms.
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FMFMET, NUK, UL, UM, UPUK
Evolutionary responses are required for tree populations to be able to track climate change. Results of 250 years of common garden experiments show that most forest trees have evolved local ...adaptation, as evidenced by the adaptive differentiation of populations in quantitative traits, reflecting environmental conditions of population origins. On the basis of the patterns of quantitative variation for 19 adaptation‐related traits studied in 59 tree species (mostly temperate and boreal species from the Northern hemisphere), we found that genetic differentiation between populations and clinal variation along environmental gradients were very common (respectively, 90% and 78% of cases). Thus, responding to climate change will likely require that the quantitative traits of populations again match their environments. We examine what kind of information is needed for evaluating the potential to respond, and what information is already available. We review the genetic models related to selection responses, and what is known currently about the genetic basis of the traits. We address special problems to be found at the range margins, and highlight the need for more modeling to understand specific issues at southern and northern margins. We need new common garden experiments for less known species. For extensively studied species, new experiments are needed outside the current ranges. Improving genomic information will allow better prediction of responses. Competitive and other interactions within species and interactions between species deserve more consideration. Despite the long generation times, the strong background in quantitative genetics and growing genomic resources make forest trees useful species for climate change research. The greatest adaptive response is expected when populations are large, have high genetic variability, selection is strong, and there is ecological opportunity for establishment of better adapted genotypes.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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