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1.
Sci Total Environ ; 946: 174291, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38944308

RESUMEN

This study contributes a first comparison of current and potential threats to Natural World Heritage Sites from climate change, as assessed by experts, when site and location characteristics (size, year of inscription to the World Heritage list, continent, climate zone and kind of site) are controlled for. The probability of a threat as well as its intensity is analysed. Another novelty lies in the use of data from the IUCN Conservation Outlook Assessment, covering all 245 Natural and Mixed World Heritage Sites across the world for three points in time: 2014, 2017 and 2020. The threat of climate change is broadly defined and includes temperature extremes, rising temperatures, disappearing glaciers, coral bleaching, droughts, desertification, and rising sea levels. Results based on a simultaneous Probit model with random effects show that the probability of actual and potential climate change threats increases over time, but with differences for size, kind of site and location. The probability that a threat is identified is highest for marine and coastal sites, and for those in Latin America, while it is significantly lower for sites on the African continent. Larger sites have a higher probability of being assessed as at risk and the severity of threats is found to be lower for recently inscribed sites. The rate at which the likelihood of a threat assessment increases is consistent for both current and future situations, while the probability of the most severe threat is larger for the current than the future period. A serious threat from climate change is assessed as highest for locations in the tropical monsoon (current period) or the tropical savannah climate (future period). Estimations also show that pure descriptive statistics or bivariate correlations may not correctly identify the risk or the dignity of a threat.

2.
Chem Rev ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842266

RESUMEN

This roadmap reviews the new, highly interdisciplinary research field studying the behavior of condensed matter systems exposed to radiation. The Review highlights several recent advances in the field and provides a roadmap for the development of the field over the next decade. Condensed matter systems exposed to radiation can be inorganic, organic, or biological, finite or infinite, composed of different molecular species or materials, exist in different phases, and operate under different thermodynamic conditions. Many of the key phenomena related to the behavior of irradiated systems are very similar and can be understood based on the same fundamental theoretical principles and computational approaches. The multiscale nature of such phenomena requires the quantitative description of the radiation-induced effects occurring at different spatial and temporal scales, ranging from the atomic to the macroscopic, and the interlinks between such descriptions. The multiscale nature of the effects and the similarity of their manifestation in systems of different origins necessarily bring together different disciplines, such as physics, chemistry, biology, materials science, nanoscience, and biomedical research, demonstrating the numerous interlinks and commonalities between them. This research field is highly relevant to many novel and emerging technologies and medical applications.

3.
J Environ Manage ; 360: 121113, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38772229

RESUMEN

This study contributes an empirical investigation of the likelihood that different external threats to a UNESCO Natural World Heritage Site occur in combination with each other when site characteristics and location are controlled for. For the purpose of the analysis, the World Heritage database and the UNESCO State of Conservation Reports are used and the nine most frequently appearing external threats are identified. These databases include 6852 site-year observations and 3316 threats over the period 1979-2023. The most commonly identified external threats are illegal activities, with eleven percent of all observations and mining with six percent. Transport infrastructure, tourism and visitor pressure are also common threats. Estimation results based on the multivariate Probit (equation system) model demonstrate that there are strong positive correlations between many pairs of the nine external threats. Most apparent are the links between illegal activities and loss of identity, social cohesion, changes in local population and community, water infrastructure (dams) and farming, as well as illegal activities and land conversion. There are also clear links between tourism and infrastructure. This emphasises that the various threats seldom appear in isolation from each other. Results also highlight that the threats have different drivers. Among the determinants, site characteristics and location are the most important ones. The likelihood of threats is highest for Natural Heritage Sites covered by forests or those in marine and coastal areas, Africa as well as the Arab region. It is also possible to identify a general increase in threats over time, although with a diminishing rate of growth towards the period 2015-2019. Contrary to this development and the general downturn in threats during the Covid-19 pandemic period of 2020-2023, pressure from tourism continues to grow. Methodologically, the results emphasize the need for multivariate Probit models when research goes beyond analyses of descriptive statistics and single equation approaches.


Asunto(s)
Conservación de los Recursos Naturales , Turismo , Humanos , Minería , Agricultura
4.
Heliyon ; 10(1): e22871, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38332876

RESUMEN

This paper introduces Heliyon's Business and Management Section, established in 2023 as a platform committed to maintaining rigorous ethical and scientific publishing standards within the field. Prioritizing scientific correctness and technical soundness over mere novelty, it encompasses a wide range of research domains, encouraging contributions from scholars across diverse backgrounds. Within this guide, we provide insights into the process of preparing effective papers and offer constructive guidelines for the reviewing process. Authors will find valuable tools to align their work with the journal's expectations, incorporating current literature to enhance the probability of successful publication. Both aspiring authors and reviewers will benefit from this resource, which emphasizes academic and professional growth. By promoting collaboration and upholding high-quality standards, we aim to fortify the scholarly publishing community and advance knowledge in the field of business and management.

5.
Int J Biometeorol ; 68(3): 581-593, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36607447

RESUMEN

This study investigates empirically how natural snow depth and permanent snow affect the number of new second homes in Norway. One out of four Norwegian municipalities is partly covered by glaciers and permanent snow. In the winter seasons of 1983-2020, there is a decline in snow depth from 50 to 35 cm on average (based on 41 popular second-home areas in the mountains). Results of the fixed effects Poisson estimator with spatial elements show that there is a significant and positive relationship between natural snow depth in the municipality and the number of second homes started. There is also a significant and negative relationship between the number of new second homes in the municipality and a scarcity of snow in the surrounding municipalities. However, the magnitude of both effects is small. Estimates also show a strong positive relationship between the proportion of surface covered by permanent snow or glaciers in the municipality and new second homes. This implies that a decline in permanent snow and glaciers may make these areas less attractive for the location of second homes.


Asunto(s)
Monitoreo del Ambiente , Nieve , Monitoreo del Ambiente/métodos , Estaciones del Año , Cubierta de Hielo
6.
Biol Chem ; 405(3): 177-187, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-37712609

RESUMEN

Nitro-fatty acids (NFAs) are endogenous lipid mediators capable of post-translational modifications of selected regulatory proteins. Here, we investigated the anti-cancerous effects of nitro-oleic acid (NO2OA) and its combination with gamma irradiation on different cancer cell lines. The effects of NO2OA on cell death, cell cycle distribution, or expression of p21 and cyclin D1 proteins were analyzed in cancer (A-549, HT-29 and FaDu) or normal cell lines (HGF, HFF-1). Dose enhancement ratio at 50 % survival fraction (DERIC50) was calculated for samples pre-treated with NO2OA followed by gamma irradiation. NO2OA suppressed viability and induced apoptotic cell death. These effects were cell line specific but not in general selective for cancer cells. HT-29 cell line exerted higher sensitivity toward NO2OA treatment among cancer cell lines tested: induction of cell cycle arrest in the G2/M phase was associated with an increase in p21 and a decrease in cyclin D1 expression. Pre-treatment of HT-29 cells with NO2OA prior irradiation showed a significantly increased DERIC50, demonstrating radiosensitizing effects. In conclusion, NO2OA exhibited potential for combined chemoradiotherapy. Our results encourage the development of new NFAs with improved features for cancer chemoradiation.


Asunto(s)
Ciclina D1 , Nitrocompuestos , Humanos , Ácidos Oléicos , Ácidos Grasos , Células HT29
8.
Diagn Pathol ; 18(1): 73, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37308870

RESUMEN

Abdominal aortic aneurysm (AAA) is a pathologic enlargement of the infrarenal aorta with an associated risk of rupture. However, the responsible mechanisms are only partially understood. Based on murine and human samples, a heterogeneous distribution of characteristic pathologic features across the aneurysm circumference is expected. Yet, complete histologic workup of the aneurysm sac is scarcely reported. Here, samples from five AAAs covering the complete circumference partially as aortic rings are investigated by histologic means (HE, EvG, immunohistochemistry) and a new method embedding the complete ring. Additionally, two different methods of serial histologic section alignment are applied to create a 3D view. The typical histopathologic features of AAA, elastic fiber degradation, matrix remodeling with collagen deposition, calcification, inflammatory cell infiltration and thrombus coverage were distributed without recognizable pattern across the aneurysm sac in all five patients. Analysis of digitally scanned entire aortic rings facilitates the visualization of these observations. Immunohistochemistry is feasible in such specimen, however, tricky due to tissue disintegration. 3D image stacks were created using open-source and non-generic software correcting for non-rigid warping between consecutive sections. Secondly, 3D image viewers allowed visualization of in-depth changes of the investigated pathologic hallmarks. In conclusion, this exploratory descriptive study demonstrates a heterogeneous histomorphology around the AAA circumference. Warranting an increased sample size, these results might need to be considered in future mechanistic research, especially in reference to intraluminal thrombus coverage. 3D histology of such circular specimen could be a valuable visualization tool for further analysis.


Asunto(s)
Calcinosis , Imagenología Tridimensional , Humanos , Animales , Ratones
9.
Artículo en Inglés | MEDLINE | ID: mdl-37327104

RESUMEN

In structural biology, validation and verification of new atomic models are crucial and necessary steps which limit the production of reliable molecular models for publications and databases. An atomic model is the result of meticulous modeling and matching and is evaluated using a variety of metrics that provide clues to improve and refine the model so it fits our understanding of molecules and physical constraints. In cryo electron microscopy (cryo-EM) the validation is also part of an iterative modeling process in which there is a need to judge the quality of the model during the creation phase. A shortcoming is that the process and results of the validation are rarely communicated using visual metaphors. This work presents a visual framework for molecular validation. The framework was developed in close collaboration with domain experts in a participatory design process. Its core is a novel visual representation based on 2D heatmaps that shows all available validation metrics in a linear fashion, presenting a global overview of the atomic model and provide domain experts with interactive analysis tools. Additional information stemming from the underlying data, such as a variety of local quality measures, is used to guide the user's attention toward regions of higher relevance. Linked with the heatmap is a three-dimensional molecular visualization providing the spatial context of the structures and chosen metrics. Additional views of statistical properties of the structure are included in the visual framework. We demonstrate the utility of the framework and its visual guidance with examples from cryo-EM.

10.
Dev Cell ; 58(16): 1462-1476.e8, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37339629

RESUMEN

Cell proliferation is a central process in tissue development, homeostasis, and disease, yet how proliferation is regulated in the tissue context remains poorly understood. Here, we introduce a quantitative framework to elucidate how tissue growth dynamics regulate cell proliferation. Using MDCK epithelial monolayers, we show that a limiting rate of tissue expansion creates confinement that suppresses cell growth; however, this confinement does not directly affect the cell cycle. This leads to uncoupling between rates of cell growth and division in epithelia and, thereby, reduces cell volume. Division becomes arrested at a minimal cell volume, which is consistent across diverse epithelia in vivo. Here, the nucleus approaches the minimum volume capable of packaging the genome. Loss of cyclin D1-dependent cell-volume regulation results in an abnormally high nuclear-to-cytoplasmic volume ratio and DNA damage. Overall, we demonstrate how epithelial proliferation is regulated by the interplay between tissue confinement and cell-volume regulation.


Asunto(s)
Células Epiteliales , Células Epiteliales/metabolismo , Ciclo Celular/fisiología , División Celular , Epitelio , Proliferación Celular
11.
Proc Natl Acad Sci U S A ; 120(27): e2219558120, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37364104

RESUMEN

Evolution in time-varying environments naturally leads to adaptable biological systems that can easily switch functionalities. Advances in the synthesis of environmentally responsive materials therefore open up the possibility of creating a wide range of synthetic materials which can also be trained for adaptability. We consider high-dimensional inverse problems for materials where any particular functionality can be realized by numerous equivalent choices of design parameters. By periodically switching targets in a given design algorithm, we can teach a material to perform incompatible functionalities with minimal changes in design parameters. We exhibit this learning strategy for adaptability in two simulated settings: elastic networks that are designed to switch deformation modes with minimal bond changes and heteropolymers whose folding pathway selections are controlled by a minimal set of monomer affinities. The resulting designs can reveal physical principles, such as nucleation-controlled folding, that enable such adaptability.

12.
Comput Struct Biotechnol J ; 21: 2018-2034, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36968017

RESUMEN

The cell as a system of many components, governed by the laws of physics and chemistry drives molecular functions having an impact on the spatial organization of these systems and vice versa. Since the relationship between structure and function is an almost universal rule not only in biology, appropriate methods are required to parameterize the relationship between the structure and function of biomolecules and their networks, the mechanisms of the processes in which they are involved, and the mechanisms of regulation of these processes. Single molecule localization microscopy (SMLM), which we focus on here, offers a significant advantage for the quantitative parametrization of molecular organization: it provides matrices of coordinates of fluorescently labeled biomolecules that can be directly subjected to advanced mathematical analytical procedures without the need for laborious and sometimes misleading image processing. Here, we propose mathematical tools for comprehensive quantitative computer data analysis of SMLM point patterns that include Ripley distance frequency analysis, persistent homology analysis, persistent 'imaging', principal component analysis and co-localization analysis. The application of these methods is explained using artificial datasets simulating different, potentially possible and interpretatively important situations. Illustrative analyses of real complex biological SMLM data are presented to emphasize the applicability of the proposed algorithms. This manuscript demonstrated the extraction of features and parameters quantifying the influence of chromatin (re)organization on genome function, offering a novel approach to study chromatin architecture at the nanoscale. However, the ability to adapt the proposed algorithms to analyze essentially any molecular organizations, e.g., membrane receptors or protein trafficking in the cytosol, offers broad flexibility of use.

13.
Scientometrics ; 128(3): 1963-1985, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36844385

RESUMEN

This study examines the formats offered for academic conferences in the mature stages of the COVID-19 pandemic. Two out of three organisers discontinue their usage of online video tools and focus on in-person conferences. Only one out of five conferences offers hybrid solutions and even fewer a virtual alternative (13%). Data for the analysis originate from 547 calls for proposals announced in Spring 2022 for conferences to be held during the period August 2022 to July 2023. Estimates using a multinomial logit model show that the planning time is significantly related to the choice of format offered. The longer the lead time, the more likely it is to offer an in-person conference. International travel restrictions and bans on gatherings for the location of the venue at the time of planning are significantly related to the choice of virtual, but not hybrid formats. There are also large differences in the choice across disciplines, with conferences in arts and humanities as well as natural sciences showing the lowest preference for the virtual format.

14.
Int J Mol Sci ; 24(3)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36769000

RESUMEN

Complex functioning of the genome in the cell nucleus is controlled at different levels: (a) the DNA base sequence containing all relevant inherited information; (b) epigenetic pathways consisting of protein interactions and feedback loops; (c) the genome architecture and organization activating or suppressing genetic interactions between different parts of the genome. Most research so far has shed light on the puzzle pieces at these levels. This article, however, attempts an integrative approach to genome expression regulation incorporating these different layers. Under environmental stress or during cell development, differentiation towards specialized cell types, or to dysfunctional tumor, the cell nucleus seems to react as a whole through coordinated changes at all levels of control. This implies the need for a framework in which biological, chemical, and physical manifestations can serve as a basis for a coherent theory of gene self-organization. An international symposium held at the Biomedical Research and Study Center in Riga, Latvia, on 25 July 2022 addressed novel aspects of the abovementioned topic. The present article reviews the most recent results and conclusions of the state-of-the-art research in this multidisciplinary field of science, which were delivered and discussed by scholars at the Riga symposium.


Asunto(s)
Núcleo Celular , Genoma , Núcleo Celular/metabolismo , Diferenciación Celular/genética
15.
Environ Manage ; 71(2): 285-303, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36639605

RESUMEN

This study offers new insights into the largest threats to natural and mixed World Heritage sites in developed countries as considered by their management. In addition to this, the capacity of the management to deal with threats is examined. An Ordered Probit model is used that distinguishes three groups of threats and four categories of adaptive capacity of the management. Data originate from the 2014 UNESCO Periodic Report II for sites in economically advanced countries (Europe, North America, Australia, New Zealand, Japan and South Korea) linked to the World Heritage Site database. Estimation results reveal that the probability of a major threat to World Heritage sites is perceived to be highest in the category of climate change and extreme weather events, followed by local conditions affecting the physical structure (temperature, rain, dust). Sites in tropical climates are perceived as significantly more threatened, as are those earlier listed as in danger. The likelihood of perceiving a major threat is highest in Turkey, Italy, Norway and North America. Threats related to climate change are those the management has the lowest capacity to deal with when other important aspects are controlled for. Large and natural areas have a higher perceived administrative capacity to deal with threats than others.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Conservación de los Recursos Naturales/métodos , Percepción , Países Desarrollados , Humanos
16.
ArXiv ; 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38235062

RESUMEN

Learning algorithms based on backpropagation have enabled transformative technological advances but alternatives based on local energy-based rules offer benefits in terms of biological plausibility and decentralized training. A broad class of such local learning rules involve \textit{contrasting} a clamped configuration with the free, spontaneous behavior of the system. However, comparisons of clamped and free configurations require explicit memory or switching between Hebbian and anti-Hebbian modes. Here, we show how a simple form of implicit non-equilibrium memory in the update dynamics of each ``synapse'' of a network naturally allows for contrastive learning. During training, free and clamped behaviors are shown in sequence over time using a sawtooth-like temporal protocol that breaks the symmetry between those two behaviors when combined with non-equilibrium update dynamics at each synapse. We show that the needed dynamics is implicit in integral feedback control, broadening the range of physical and biological systems naturally capable of contrastive learning. Finally, we show that non-equilibrium dissipation improves learning quality and determine the Landauer energy cost of contrastive learning through physical dynamics.

17.
Life Sci ; 310: 121106, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36272465

RESUMEN

AIMS: Limited number of agents that provide protection against hematopoietic acute radiation syndrome led us to the evaluation of nitro-oleic acid (NO2OA) as a potential protector/mitigator against radiation-induced hematopoietic injury in C57/BL6 mice. MATERIALS AND METHODS: NO2OA was administered before and after sub-lethal total body irradiation (TBI) and hematological parameters were evaluated 3 or 7 days after TBI. KEY FINDINGS: Our results show that NO2OA significantly increase bone marrow cellularity including the granulocyte-macrophage colony-forming cells and erythroid progenitors on the 3rd day after TBI. In addition, NO2OA enhanced recovery of white blood cells (lymphocytes, neutrophils, and monocytes) in peripheral blood 7 days after irradiation. These effects may be in part attributed to NO2OA-induced granulocyte colony-stimulating factor production after TBI. On the other hand, radiation-induced impairment of peripheral red blood cells, hemoglobin, and platelets were not affected with NO2OA treatment up to 7 days post TBI. SIGNIFICANCE: In conclusion, our data show that NO2OA significantly protects hematopoiesis after irradiation, and thus showed a high potential to act as an agent for medical radiation countermeasure.


Asunto(s)
Médula Ósea , Células Madre Hematopoyéticas , Ratones , Animales , Hematopoyesis/efectos de la radiación , Irradiación Corporal Total , Factor Estimulante de Colonias de Granulocitos/farmacología , Proteínas Recombinantes/farmacología , Ratones Endogámicos C57BL
18.
Nature ; 611(7934): 68-73, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36289343

RESUMEN

Objects that deform a liquid interface are subject to capillary forces, which can be harnessed to assemble the objects1-4. Once assembled, such structures are generally static. Here we dynamically modulate these forces to move objects in programmable two-dimensional patterns. We 3D-print devices containing channels that trap floating objects using repulsive capillary forces5,6, then move these devices vertically in a water bath. Because the channel cross-sections vary with height, the trapped objects can be steered in two dimensions. The device and interface therefore constitute a simple machine that converts vertical to lateral motion. We design machines that translate, rotate and separate multiple floating objects and that do work on submerged objects through cyclic vertical motion. We combine these elementary machines to make centimetre-scale compound machines that braid micrometre-scale filaments into prescribed topologies, including non-repeating braids. Capillary machines are distinct from mechanical, optical or fluidic micromanipulators in that a meniscus links the object to the machine. Therefore, the channel shapes need only be controlled on the scale of the capillary length (a few millimetres), even when the objects are microscopic. Consequently, such machines can be built quickly and inexpensively. This approach could be used to manipulate micrometre-scale particles or to braid microwires for high-frequency electronics.

19.
J Environ Manage ; 324: 116250, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36166868

RESUMEN

Due to their remoteness or boundless nature, activities at Natural Heritage Sites are difficult to monitor. In this study, two digital measures of the interest in Natural Word Heritage Sites are compared: one ex ante based on the number of Wikipedia page views of the site and another ex post derived from actual visitation as measured by the number of Instagram posts. The entire UNESCO database, which includes 248 Natural World Heritage Sites is linked to the 2.8 million Wikipedia page views, the 58 million Instagram posts and the Köppen extreme climate zone categories. Quantile regressions reveal that the main association in common for the two indicators is the risk of the site losing its inscription. Presence in the UNESCO Danger list is associated with reduced interest in a site, particularly in the number of Instagram posts and in the top quartile of Wikipedia views. Years since inscription is also an important explanatory variable, especially for the Instagram posts and the Wikipedia views in the top quartile. The UNESCO selection criterion of outstanding beauty only relates to the Instagram posts. Climate zone is mainly linked to the ex post variable and its upper quartile, where the sites with the most attention are found. Wikipedia views are also negatively associated with sites in Africa, the Arab countries and Latin America. Elevation, size of the area as well as kind of site are all variables not significant. There is a significant correlation between the two outcome variables with a coefficient of 0.5. While the Instagram posts relate clearly to actual visits, the Wikipedia page views is considered a possible leading indicator of future interest in a site.


Asunto(s)
Conservación de los Recursos Naturales , Medios de Comunicación Sociales , Humanos , África , Medio Oriente , América Latina
20.
Ann Reg Sci ; 69(2): 537-553, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669629

RESUMEN

This study investigates empirically changes in domestic summer tourism demand following the Covid-19 pandemic in 305 regions across six European countries (Denmark, Finland, France, Italy, Spain and Sweden) based on official data. Five different groups of NUTS 3 regions are identified in accordance with a typology suggested by the OECD where density and connectivity are aspects of importance. Dynamic panel data estimations show that large metropolitan regions experience strong decreases in demand (approximately 30 per cent) both in July and August 2020. There are, however, clear differences between the Northern and Southern European countries. In the North, the remote regions encounter an increased demand that is partially offsetting losses in the large metropolitan regions. This pattern cannot be found in the South. The decline in domestic tourism flows to the major metropolitan areas is also more pronounced in the South of Europe, approximately 50 per cent per summer month compared with 20 per cent (July 2020) and stagnation (August 2020) in the North regions.

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