There is direct evidence for the spread of infectious diseases such as influenza, SARS, measles, and norovirus in locations where large groups of people gather at high densities e.g. theme parks, ...airports, etc. The mixing of susceptible and infectious individuals in these high people density man-made environments involves pedestrian movement which is generally not taken into account in modeling studies of disease dynamics. We address this problem through a multiscale model that combines pedestrian dynamics with stochastic infection spread models. The pedestrian dynamics model is utilized to generate the trajectories of motion and contacts between infected and susceptible individuals. We incorporate this information into a stochastic infection dynamics model with infection probability and contact radius as primary inputs. This generic model is applicable for several directly transmitted diseases by varying the input parameters related to infectivity and transmission mechanisms. Through this multiscale framework, we estimate the aggregate numbers and probabilities of newly infected people for different winding queue configurations. We find that the queue configuration has a significant impact on disease spread for a range of infection radii and transmission probabilities. We quantify the effectiveness of wall separators in suppressing the disease spread compared to rope separators. Further, we find that configurations with short aisles lower the infection spread when rope separators are used.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Sandy islands suffer multiple external disturbances and thus experience drastic temporal ecological changes, and the two parts, that is, the states of essential components (Part 1) and the resilience ...under multiple disturbances (Part 2), are both indispensable to the sandy island ecosystem health. In this study, a model for the sandy island ecosystem health was established by integrating the two parts. In Part 1, the states were measured following the framework of vegetation, soil, and landscape, and a total of 12 factors in the three components were adopted. In Part 2, three typical disturbances, namely, geomorphological change, soil salinization, and human influence, were identified, and the resilience across different time intervals was measured by clarifying the intrinsic correlations between the components and disturbances. A sandy island ecosystem health index (SIEHI) was proposed based on the two parts, and Chongming Island was selected as the study area to demonstrate the model. The results indicated that the SIEHI continuously increased from 1988 to 2017, denoting the good effects of “Eco-Island construction” on Chongming Island. In different components and factors, the vegetation and soil components contributed more than the landscape component to the sandy island ecosystem health, and vegetation quality and soil carbon/nitrogen were the factors that made the most contributions. In different disturbances, the human influence played a major role in driving the spatiotemporal variations of the sandy island ecosystem health. Farming and building construction contributed the most and accounted for 37.12% and 35.59% of the total human influence, respectively, while traffic development exerted the highest influence per area. Then, influence coefficients of different human activities on the sandy island were determined, and measures for different functional zones were proposed for balancing the protection and development and achieving the sandy island ecosystem-based management.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•A three-class carbon pool system was proposed to normalize coastal carbon mapping and accounting.•The carbon sink storage, increment, and value were mapped and accounted based on the system.•The ...carbon increments per area of vegetation and soil were 6.03 Mg/ha and 0.47 Mg/ha, respectively.•Increments of vegetation and soil carbon pools were distinctly higher in salt marshes than in land areas.•The carbon sink value was decreased by 2.14% when alien species is replaced by native ones.
Climate change is a key issue receiving increasing global attention. Coastal areas play an important role in mitigating climate change because of enormous potentials for carbon sequestration. Simulating and evaluating the carbon storage, increment, and value of coastal areas is of considerable importance in achieving carbon neutrality. In this study, the South Coast of Hangzhou Bay in China was selected as the study area. A three-class carbon pool system was established based on vegetation and soil and considering the coastline as the boundary for comprehensively revealing the carbon sink in coastal areas and accurately distinguishing the roles of different carbon pools. Then, the maps of carbon storage and increment were generated by integrating the field and remote sensing data through “from point to area” spatial simulations. An accounting list was developed for systematically summarizing, precisely quantifying, and visually displaying the carbon storage, increment, and value following the three-class carbon pools. Results indicated that the carbon sink showed a gradient change from sea to land. Salt marshes had low storage but high increment, whereas areas above the coastline had the opposite characteristics. The total carbon storage of vegetation and soil were 1417.94 Gg and 3359.07 Gg, respectively, and their carbon increments during 2011–2022 were 309.17 Gg/yr and 29.46 Gg/yr, respectively. The carbon storage per area of vegetation and soil were 27.66 Mg/ha and 53.09 Mg/ha, respectively, and their carbon increments during 2011–2022 were 6.03 Mg/(ha yr) and 0.47 Mg/(ha yr), respectively. As the main body of blue carbon, salt marshes have achieved distinctly higher increment than the adjacent areas above the coastline. The carbon increment per area of soil was lower than 1/5 of vegetation in salt marshes. Mudflats had low carbon increment but large storage because of the extensive area. Alien species had higher increment in terms of vegetation but similar one from the perspective of soil compared with native species, denoting the low decrease of soil carbon sink when eliminating alien species. Considering the hazard of alien species to the health of coastal wetlands, this indicates the feasibility and necessity to develop the high-quality carbon sink in the study area. The carbon sink value based on the carbon stored in the soil summed to 1.68 million yuan, and were increased by 33%, 7%, 48%, and 45% in scenarios of baseline scenario, economic development, ecological protection, and comprehensive optimization, respectively. The present study validated the high carbon increment and immense increase potential and provided an applicable system to normalize carbon mapping and accounting in coastal areas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Embryonic stem cells (ESCs) can be maintained in culture indefinitely while retaining the capacity to generate any type of cell in the body, and therefore not only hold great promise for tissue ...repair and regeneration, but also provide a powerful tool for modeling human disease and understanding biological development. In order to fulfill the full potential of ESCs, it is critical to understand how ESC fate, whether to self-renew or to differentiate into specialized cells, is regulated. On the molecular level, ESC fate is controlled by the intracellular transcriptional regulatory networks that respond to various extrinsic signaling stimuli. In this review, we discuss and compare important signaling pathways in the self-renewal and differentiation of mouse, rat, and human ESCs with an emphasis on how these pathways integrate into ESC-specific transcription circuitries. This will be beneficial for understanding the common and conserved mechanisms that govern self-renewal, and for developing novel culture conditions that support ESC derivation and maintenance.
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EMUNI, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UL, UM, UPUK, VKSCE, ZAGLJ
Secondary crashes or crashes that occur in the wake of a preceding or primary crash are among the most critical incidents occurring on highways, due to the exceptional danger they present to the ...first responders and victims of the primary crash. In this work, we developed a self-exciting temporal point process to analyze crash events data and classify it into primary and secondary crashes. Our model uses a self-exciting function to describe secondary crashes while primary crashes are modeled using a background rate function. We fit the model to crash incidents data from the Florida Department of Transportation, on Interstate-4 (I-4) highway for the years 2015-2017, to determine the model parameters. These are used to estimate the probability that a given crash is secondary crash and to find queue times. To represent the periodically varying traffic levels and crash incidents, we model the background rate, as a stationary function, a sinusoidal non-stationary function, and a piecewise non-stationary function. We show that the sinusoidal non-stationary background rate fits the traffic data better and replicates the daily and weekly peaks in crash events due to traffic rush hours. Secondary crashes are found to account for up to 15.09% of traffic incidents, depending on the city on the I-4 Highway.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•We analyzed the impact of urban expansion on crucial ecosystem services in coastal zones.•We mapped and compared urban expansion in the China’s five coastal megacities.•The conversion of cropland to ...the urban area was the principal contributor to the loss of carbon storage.•The habitat quality loss and degradation mostly due to the forest occupation by urban land.
Urban zones across the world have experienced a massive expansion in recent decades, affecting food production, carbon storage, and biodiversity, and further threatening the realization of the UN’s Sustainable Development Goals (SDGs), particularly SDG 2 (zero hunger), 13 (climate action), and 15 (life on land). These enormous impacts are even more worrying in coastal areas where urbanization has been continuously accelerated. However, we have a poor understanding about the magnitude of the reduction in natural habitat and crucial ecosystem services over time caused by urban expansion in coastal areas. Here we chose the coastal zone of eastern China using a high-resolution dataset of land-use/land-cover (LULC) to investigate the influences of urban growth on natural habitat and crucial ecosystem services from 1990 to 2018. The results showed that: (1) urban growth in China's coastal region resulted in an estimated reduction of 2061.14 km2 in natural habitat, 154.13 Tg C in carbon storage, 1.67 Tg C in cropland net primary production, and 148.02 × 103 in habitat quality; (2) cropland net primary production loss resulted in a 1.34 × 106 tons loss of crop production, which is comparable to meeting the basic food demands of 3.35 million hungry people for a year; (3) the overall degradation of habitat caused by urban expansion reached 1838.28 km2, with grade 1 degradation area accounting for the largest portion (801.18 km2), representing 43.58% of the total degradation; (4) the primary contributor to carbon storage loss (63.83%) was the large-scale conversion of cropland to urban areas, while habitat quality loss and degradation were primarily due to the occupation of forests by urban expansion (42.62%). Our results suggest that effective land-use planning must be implemented to coordinate urban growth, natural habitat protection, and cropland displacement in rapidly urbanizing coastal areas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Simulation accuracy and cost are two core issues in soil organic carbon mapping.•A zonal simulation approach was proposed for realizing high accuracy and low cost.•A typical subzone with an area ...proportion <20% of the study area was identified.•The zonal simulation achieves high accuracy with a cost decrease by more than 50%.•Geographical integrity, typicalness, and scale are key points of zonal simulation.
Digital soil mapping (DSM) has been developed for decades and aims to accurately simulate the soil factors with low cost. However, it still cost considerably in coastal wetlands because of the high difficulty in field survey. A zonal simulation approach was proposed for decreasing the cost of field survey in the premise of high accuracy for soil organic carbon stock mapping in coastal wetlands, and Chongming Island, an important estuarine wetland in China, was used to demonstrate the study. A subzone with an area proportion lower than 20% was identified based on the typicalness of land surface characteristics and soil influencing factors for the whole study area. Entire and zonal simulations were conducted using abundant predictors sourced from remote sensing, partial least square regression, and 10-fold cross validation. The results revealed that root mean squared errors of entire and zonal simulations were 1.70 g/kg and 1.95 g/kg, respectively, which were in a low level compared with those in previous studies and indicated the high simulation accuracy. The zonal simulation exhibited a slightly lower accuracy than the entire simulation, while considerably decreased the cost by more than 50%. The decrease in the cost showed a much more practical significance than the increase in the accuracy in areas with high difficulty in field survey, and the geographical integrity and continuity of the whole study area, the typicalness of the selected subzone, and the spatial extent were the three key points when promoting the zonal simulation in DSM. The soil organic carbon stock in the study area was generally high in areas with good vegetation condition, low soil salinity, complex landscape configuration, and long distances from the sea. Human activities and the resulting landscape fragmentation have been the dominant factor that drives the spatial pattern of soil organic carbon stock.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study seeks to provide a basic approach to fulfill the spatial visualization of geopolitical environmental factors required for the navigation of vessels in the Arctic. Multi-dimensional ...geopolitical environmental factors of the Arctic Passage are analyzed and classified into geopolitics, geoeconomics, geo-military, geoculture, and laws and regulations related to geography. Their characteristics are extracted to form an attribute information table matching spatial layers. Based on the information category and basic characteristics, the spatial match method is applied and connected with the spatial layers to examine the spatial point, polyline, and polygon. According to the qualitative description, the study extracted the quantitative indicators for the following spatial–temporal pattern analysis. The standard deviational ellipse is used to analyze the spatial–temporal patterns and trends of the geopolitical environmental indicators of the Arctic Passage in the Arctic and Northeast Asia. The expansion and contraction of geoinformation coexist in the countries surrounding the Arctic Passage. The spatial–temporal changes indicate that the Arctic channel has a great economic impact on the Nordic countries and Northeast Asia, especially the coastal areas of China and Japan. The characteristic extraction and spatial match of the geopolitical environment provide integrated Arctic geoinformation inquiry and services for the diplomatic, administrative, and legal preparations required for Arctic navigation. Therefore, the geospatial analysis conducted provides scientific support and a basis for the geographical distribution and developing trends of visualization and spatial–temporal pattern in Arctic navigation. The results of this research will help decision-makers to make a comprehensive judgment on governance related to the sustainable development of the Arctic Passage.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
4-1BB agonists for cancer immunotherapy have shown good preliminary efficacy in clinical trials, but several of the first-generation 4-1BB agonistic antibodies entering the clinic have failed due to ...safety issues. Selenium nanoparticles (SeNPs) exhibit anti-inflammatory, anti-tumor, antioxidant, and immune-modulating properties. In addition, they have been shown to have detoxifying effects and prevent oxidative liver damage. In this study, we used an anti-4-1BB antibody in combination with SeNPs to evaluate the anti-lung cancer effects in in vitro and in vivo experiments and explore the underlying mechanisms by pathological analyses, quantitative PCR, and enzyme-linked immunoassay. We found that 5 μmol·L–1 anti-4-1BB antibody combined with 1 μmol·L–1 SeNPs increased the expression of IFN-γ and promoted the killing effects of peripheral blood mononuclear cells on Lewis lung carcinoma cells, with a lethality rate up to 56.88 %. Experiments in tumor-bearing mice showed that the tumor inhibition rate was 58.61 % after treatment with 3.5 mg/kg anti-4-1BB antibody combined with 0.25 mg/kg SeNPs, and the liver function index returned to normal. When the combined treatment was compared with the antibody treatment alone, detection of immune relevant factors demonstrated that the expression of FOXP3, IL-2, IL-12, and TNF-α in the spleen was downregulated, whereas the expression of IFN-γ in the spleen, serum, and tumor was upregulated, accompanied by increased Fas ligand expression in the tumor tissues. Based on these findings, we get the conclusion that anti-4-1BB antibody combined with SeNPs may alleviate the immunosuppression of regulatory T cells, promote the immune cell proliferation and metastasis to synergistically kill tumor cells. This combination also reduces the inflammatory damage to normal tissues and slows overstimulation of the splenic immune response.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Hurricanes are powerful agents of destruction with significant socioeconomic impacts. A persistent problem due to the large-scale evacuations during hurricanes in the southeastern United States is ...the fuel shortages during the evacuation. Computational models can aid in emergency preparedness and help mitigate the impacts of hurricanes. In this paper, we model the hurricane fuel shortages using the SIR epidemic model. We utilize the crowd-sourced data corresponding to Hurricane Irma and Florence to parametrize the model. An estimation technique based on Unscented Kalman filter (UKF) is employed to evaluate the SIR dynamic parameters. Finally, an optimal control approach for refueling based on a vaccination analogue is presented to effectively reduce the fuel shortages under a resource constraint. We find the basic reproduction number corresponding to fuel shortages in Miami during Hurricane Irma to be 3.98. Using the control model we estimated the level of intervention needed to mitigate the fuel-shortage epidemic. For example, our results indicate that for Naples- Fort Myers affected by Hurricane Irma, a per capita refueling rate of 0.1 for 2.2 days would have reduced the peak fuel shortage from 55% to 48% and a refueling rate of 0.75 for half a day before landfall would have reduced to 37%.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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