Probability Of Spread Research Articles

Invasion of Corbicula fluminea (Müller, 1774) (Bivalvia: Corbiculidae) in water bodies from the East Aegean River Basin in Bulgaria

Two decades after the first record of the invasive mussel Corbicula fluminea (Müller, 1774) in Bulgaria in 2001, it has been found in many surface lotic and standing waters in the Bulgarian Danube River Basin.
 The aim of the current study is to report the finding of C. fluminea in lotic environment of the East Aegean water basin in Bulgaria. Six new localities of the mussel, all situated in the lower stretches of the Tundzha (two) and Maritsa (four) River were registered. The distributional patterns of the mussel and the abundance of its populations in relation to the environmental conditions were analyzed. The adaptive character of the Corbicula, the possible path for invasion as well as the probability of rapid spread of the mussel in the largest rivers and their tributary systems in south-eastern part of Balkan Peninsula was discussed.

Rainfall prediction over Ambon Meteorological Station using Multi-Physics Ensemble WRF-ARW

One of the methods to create good forecast using WRF-ARW modelling is tuning the parameterization. However, this method cannot provide rainfall event probability. Current research result revealed that it was able to simulate and forecast some weather parameters. However, based on the verification results, there were some weather parameters which still had low accuracy. Due to such low accuracy on some weather parameters, the authors were interested in performing post-processing methods in forecasting the weather during extreme weather at Pattimura Ambon Meteorological Station. In this study, we employed multi-physics ensemble prediction system (MEPS) by combining 20 WRF-ARW parameterization schemas, which were processed to obtain the ensemble mean, ensemble spread, and basic probability to get the uncertainty from each weather parameters. Verification process was done by using spreads, skill method and ROC curves. It was discovered that MEPS products have a better skill compared to the forecast control, the correlation value of MEPS products is larger and has the lowest error value. In addition, the result of ROC curves shows that the MEPS has an ability to predict weather condition during cloudy and extreme rain.

Probabilistic Analysis of the Obstruction of Water Sources Due to the Occurrence of Rainfall-Triggered Mass Movements

This paper presents a methodology for the probabilistic estimation of the obstruction of water streams generated by shallow mass movements triggered by rainfall. The study focuses on the Ovejas River, a tributary stream of the Medellín River, in the jurisdiction of the municipality of San Vicente in the department of Antioquia (Colombia). The occurrence of a mass movements was evaluated by deterministic and probabilistic methods based on the automation of processes of Geographic Information Systems (GIS) and spatial modeling. The spatial distribution of the mass movement hazard was estimated in terms of Factor of Safety (FoS) values by the deterministic method with physical basis SLIDE (Slope - Infiltration - Distributed Equilibrium), which allows the hazard zonation by calculating a FoS for rainfall-induced mass movements with different return periods. The rainfall regimes of the study area are estimated by means of a simple scaling Log Normal Model. On the other hand, the Probability of Failure (PF) analysis was performed under Rosenblueth’s punctual estimates method (PEM), which allows incorporating the uncertainty of the soil parameters. Subsequently, the resulting zones with high hazard that could detach and reach the Ovejas River channel are identified as sources for runout modeling by means of the Flow R model, thus estimating the extent of mass movement in probabilistic terms. In all the analyzed scenarios, the sliding material from the critical stability zones has a high probability of spreading to the riverbed of the main river. This analysis makes possible to identify those areas of the riverbed that should be analyzed with more detail and require possible intervention for the protection of the riverbed.

Detecting critical nodes in forest landscape networks to reduce wildfire spread.

Although wildfires are an important ecological process in forested regions worldwide, they can cause significant economic damage and frequently create widespread health impacts. We propose a network optimization approach to plan wildfire fuel treatments that minimize the risk of fire spread in forested landscapes under an upper bound for total treated area. We used simulation modeling to estimate the probability of fire spread between pairs of forest sites and formulated a modified Critical Node Detection (CND) model that uses these estimated probabilities to find a pattern of fuel reduction treatments that minimizes the likely spread of fires across a landscape. We also present a problem formulation that includes control of the size and spatial contiguity of fuel treatments. We demonstrate the approach with a case study in Kootenay National Park, British Columbia, Canada, where we investigated prescribed burn options for reducing the risk of wildfire spread in the park area. Our results provide new insights into cost-effective planning to mitigate wildfire risk in forest landscapes. The approach should be applicable to other ecosystems with frequent wildfires.

Containing epidemics in a local cluster via antidote distribution and partial quarantine.

The study of spreading phenomena in networks, in particular the spread of disease, has attracted considerable interest in the network science research community. In this paper, we show that the outbreak of an epidemic can be effectively contained and suppressed in a small subnetwork by a combination of antidote distribution and partial quarantine. We improve over existing antidote distribution schemes based on personalized PageRank in two ways. First, we replace the constraint on the topology of this subnetwork described by Chung etal. [Internet Math. 6, 237 (2009)1542-795110.1080/15427951.2009.10129184] that a large fraction of the value of the personalized PageRank vector must be contained in the local cluster, with a partial quarantine scheme. Second, we derive a different lower bound on the amount of antidote. We show that, under our antidote distribution scheme, the probability of the infection spreading to the whole network is bounded, and the infection inside the subnetwork will disappear after a period that is proportional to the logarithm of the number of initially infected nodes. We demonstrate the effectiveness of our strategy with numerical simulations of epidemics on benchmark networks. We also test our strategy on two examples of epidemics in real-world networks. Our strategy is dependent only on the rate of infection, the rate of recovery, and the topology around the initially infected nodes, and is independent of the rest of the network.

Minimizing the respiratory pathogen transmission: Numerical study and multi-objective optimization of ventilation systems in a classroom

Schools are recognized as high-risk spaces in airborne infectious disease transmission due to occupant density and activity level. Therefore, it is critical to conduct studies and provide proper solutions regarding the spread of airborne transmission diseases to the lowest possible in schools. In this study, the performance of five various ventilation systems regarding control the spread of airborne particles in a classroom were studied by Computational Fluid Dynamics (CFD), and then, the best case was selected with regard to the least probability of infection spread. These cases with various locations of inlet and outlet vents are considered, and the spread of particles is studied. A multi-objective optimization process is then performed to understand the effects of design variables, including air inlet width, air change per hour (ACH), and inlet air temperature on the thermal comfort conditions according to suggested standard values and relations for calculating each of these parameters based on the design variables are proposed. Desirability functions are used to determine the range of variables that result in thermally comfortable conditions and maximum desirability of 0.952 with a width of 0.130 m, temperature of 296.60 K, and value of ACH between 9.689 and 9.858 results is obtained.

Opinion on the Policy of Lifting Restrictions to Entry Under the Circumstance of the COVID-19 Pandemic

Opinion on the Policy of Lifting Restrictions to Entry Under the Circumstance of the COVID-19 Pandemic

Harnessing testing strategies and public health measures to avert COVID-19 outbreaks during ocean cruises

To ensure the safe operation of schools, workplaces, nursing homes, and other businesses during COVID-19 pandemic there is an urgent need to develop cost-effective public health strategies. Here we focus on the cruise industry which was hit early by the COVID-19 pandemic, with more than 40 cruise ships reporting COVID-19 infections. We apply mathematical modeling to assess the impact of testing strategies together with social distancing protocols on the spread of the novel coronavirus during ocean cruises using an individual-level stochastic model of the transmission dynamics of COVID-19. We model the contact network, the potential importation of cases arising during shore excursions, the temporal course of infectivity at the individual level, the effects of social distancing strategies, different testing scenarios characterized by the test’s sensitivity profile, and testing frequency. Our findings indicate that PCR testing at embarkation and daily testing of all individuals aboard, together with increased social distancing and other public health measures, should allow for rapid detection and isolation of COVID-19 infections and dramatically reducing the probability of onboard COVID-19 community spread. In contrast, relying only on PCR testing at embarkation would not be sufficient to avert outbreaks, even when implementing substantial levels of social distancing measures.

A review of methods to reduce the probability of the airborne spread of COVID-19 in ventilation systems and enclosed spaces

COVID-19 forced the human population to rethink its way of living. The threat posed by the potential spread of the virus via an airborne transmission mode through ventilation systems in buildings and enclosed spaces has been recognized as a major concern. To mitigate this threat, researchers have explored different technologies and methods that can remove or decrease the concentration of the virus in ventilation systems and enclosed spaces. Although many technologies and methods have already been researched, some are currently available on the market, but their effectiveness and safety concerns have not been fully investigated. To acquire a broader view and collective perspective of the current research and development status, this paper discusses a comprehensive review of various workable technologies and methods to combat airborne viruses, e.g., COVID-19, in ventilation systems and enclosed spaces. These technologies and methods include an increase in ventilation, high-efficiency air filtration, ionization of the air, environmental condition control, ultraviolet germicidal irradiation, non-thermal plasma and reactive oxygen species, filter coatings, chemical disinfectants, and heat inactivation. Research gaps have been identified and discussed, and recommendations for applying such technologies and methods have also been provided in this article.

Trans-species transmission of Brucellae among ruminants hampering brucellosis control efforts in Egypt.

This study aimed to identify the genotypic fingerprinting of Brucella melitensis biovar 3 isolates from ruminants in Kafr El-Sheikh, Egypt, to compare with other peers globally and to highlight the epidemiology and potential causes of brucellosis control failure. A multilocus variable-number tandem-repeat analysis (MLVA 16) was carried out on 41 B.melitensis bv3 isolates, 31 from the preferential hosts (28 sheep and three goats) and 10 from atypical hosts (nine cattle and one buffalo), identified by bacteriological and molecular techniques. MLVA-16 analysis revealed 19 genotypes with nine as singletons. The most prevalent genotypes were M3_K.E (3,5,3,13,1,1,3,3,7,43,8,7,6,7,5,3), M13_K.E (3,5,3,13,1,1,3,3,7,43,8,5,8,7,7,3) and M5_K.E (3,5,3,13,1,1,3,3,7,43,8,4,8,7,11,3) circulating between different animal species. The B.melitensis isolation from aborted cows in farms that had never reared small ruminants indicates the likelihood of cow to cow B.melitensis transmission. Different genotypes of B.melitensis could be isolated from the same animal. The local geographic distribution of genotypes showed a very close genetic relatedness with genotypes reported outside the study area. Worldwide, our genotypes were mostly related to the Western Mediterranean lineage and less likely to the America's clonal lineage. There is a high genetic similarity of B.melitensis bv3 genotypes among different ruminant species, and the same animal could be infected with different genotypes. There is a high probability of spreading of B.melitensis among atypical hosts in the absence of the original hosts. The genetic relatedness of B.melitensis bv3 genotypes in the study area with other different geographic areas highlighted the national and international ruminants movement role as a potential factor for maintaining B.melitensis infection. Further investigations are required to understand the impact of the presence of more than one genotype of B.melitensis in the same animal on the efficacy of brucellosis control strategies.

Abstract SY02-01: Using the hallmarks of metastasis to develop antimetastatic treatments

Abstract SY02-01: Using the hallmarks of metastasis to develop antimetastatic treatments

Reconsidering evidence of moral contagion in online social networks.

The ubiquity of social media use and the digital data traces it produces has triggered a potential methodological shift in the psychological sciences away from traditional, laboratory-based experimentation. The hope is that, by using computational social science methods to analyse large-scale observational data from social media, human behaviour can be studied with greater statistical power and ecological validity. However, current standards of null hypothesis significance testing and correlational statistics seem ill-suited to markedly noisy, high-dimensional social media datasets. We explore this point by probing the moral contagion phenomenon, whereby the use of moral-emotional language increases the probability of message spread. Through out-of-sample prediction, model comparisons and specification curve analyses, we find that the moral contagion model performs no better than an implausible XYZ contagion model. This highlights the risks of using purely correlational evidence from large observational datasets and sounds a cautionary note for psychology's merge with big data.

Debris Flow Assessment in the Gaizi-Bulunkou Section of Karakoram Highway

Highways frequently run through the flow and accumulation areas of debris flow gullies and thus are susceptible to debris flow hazards. Assessing debris flows along highways can provide references for highway planners and debris flow control, emergency management. However, the existing assessment methods mostly neglect the essential information of the flow paths and spreading areas of debris flows at the regional scale. Taking the Gaizi Village-Bulunkou Township Section (hereinafter referred to as “the Gaizi-Bulunkou Section”) of the Karakoram highway as the study area, this research introduces a simple empirical model (the Flow-R model) and establishes a method for assessing the debris flow hazard level. The main processes include data collection, inventory of former events, calculating source areas and spreading probability, verification of the model, extraction of hazard assessment factors, and calculation of debris flow hazard levels. The results show that: 1) the accuracy, sensitivity, and positive predictive power of the Flow-R model in simulating the debris flow spreading probability of the study area were 81.87, 70.80 and 72.70%, respectively. The errors mainly occurred in the debris flow fans. 2) The calculation results make it possible to divide debris flow hazard levels into four levels. N5, N19, and N28 gullies had the highest hazard level during the study period. 3) In the Gaizi-Bulunkou Section of the Karakoram highway, during the study period, the highways with very high, high, medium, and low hazards were 4.33, 0.62, 1.41, and 1.68 km in length, respectively.

Spread of tweets in climate discussions: A case study of the 2019 Nobel Peace Prize announcement

Abstract Characterising the spreading of ideas within echo chambers is essential for understanding polarisation. In this article, we explore the characteristics of popular and viral content in climate change discussions on Twitter around the 2019 announcement of the Nobel Peace Prize, where we find the retweet network of users to be polarised into two well-separated groups of activists and sceptics. Operationalising popularity as the number of retweets and virality as the spreading probability inferred using an independent cascade model, we find that the viral themes echo and differ from the popular themes in interesting ways. Most importantly, we find that the most viral themes in the two groups reflect different types of bonds that tie the community together, yet both function to enhance ingroup connections while repulsing outgroup engagement. With this, our study sheds light, from an information-spreading perspective, on the formation and upkeep of echo chambers in climate discussions.

Host Genetic Diversity and Infectious Diseases. Focus on Wild Boar, Red Deer and Tuberculosis.

Simple SummaryGenetic diversity in wildlife is a matter of growing concern in contexts related to disease transmission and human health. Tuberculosis is a zoonotic disease with relevant consequences and can present high prevalence in wild boar and red deer populations. Here, we review studies on the genetic diversity of ungulates, wild boar, and red deer, and assess to what extent these studies consider its importance in the spread of disease. The relationship between host genetic diversity and the probability of disease spread is illustrated in Spanish populations of wild boar and red deer.Host genetic diversity tends to limit disease spread in nature and buffers populations against epidemics. Genetic diversity in wildlife is expected to receive increasing attention in contexts related to disease transmission and human health. Ungulates such as wild boar (Sus scrofa) and red deer (Cervus elaphus) are important zoonotic hosts that can be precursors to disease emergence and spread in humans. Tuberculosis is a zoonotic disease with relevant consequences and can present high prevalence in wild boar and red deer populations. Here, we review studies on the genetic diversity of ungulates and determine to what extent these studies consider its importance on the spread of disease. This assessment also focused on wild boar, red deer, and tuberculosis. We found a disconnection between studies treating genetic diversity and those dealing with infectious diseases. Contrarily, genetic diversity studies in ungulates are mainly concerned with conservation. Despite the existing disconnection between studies on genetic diversity and studies on disease emergence and spread, the knowledge gathered in each discipline can be applied to the other. The bidirectional applications are illustrated in wild boar and red deer populations from Spain, where TB is an important threat for wildlife, livestock, and humans.

Localization in Quantum Walks with a Single Lattice Defect: A Comparative Study

We study how a single lattice defect in a discrete time quantum walk affects the return probability of a quantum particle. This defect at the starting position is modeled by a quantum coin that is distinct from the others over the lattice. This coin has a dependence on \(\omega\) which quantifies the intensity of the localization. For some sorts of lattice defects, we show how the localization can have a dependence just on \(\omega\) , and also, the polar \(\alpha\) and azimuth \(\beta\) angles of the initial qubit by numerical calculations. We propose a lattice defect whose localization has additional dependence on \(\beta +\omega\), leading to extra localization profiles. We compare the quantum walks with our lattice defect to the earlier ones, and we discuss their spreading and survival probability.

SARS-CoV-2 and other main pathogenic microorganisms in the environment: Situation in Galicia and Spain

In the context of the current COVID-19 pandemic, and mostly taking a broad perspective, it is clearly relevant to study environmental factors that could affect eventual future outbreaks due to coronaviruses and/or other pathogenic microorganisms. In view of that, the authors of this manuscript review the situation of SARS-CoV-2 and other main pathogenic microorganisms in the environment, focusing on Galicia and Spain. Overall, in addition to showing local data, it is put in evidence that, summed to all efforts being carried out to treat/control this and any other eventual future epidemic diseases, both at local and global levels, a deep attention should be paid to ecological/environmental aspects that have effects on the planet, its ecosystems and their relations/associations with the probability of spreading of eventual future pandemics.

Virus-Information Coevolution Spreading Dynamics on Multiplex Networks

Virus and information spreading dynamics widely exist in complex systems. However, systematic study still lacks for the interacting spreading dynamics between the two types of dynamics. This paper proposes a mathematical model on multiplex networks, which considers the heterogeneous susceptibility and infectivity in two subnetworks. By using a heterogeneous mean-field theory, we studied the dynamic process and outbreak threshold of the system. Through extensive numerical simulations on artificial networks, we find that the virus’s spreading dynamics can be suppressed by increasing the information spreading probability, decreasing the protection power, or decreasing the susceptibility and infectivity.

Epidemic spreading in a weighted pig trade network

The inclusion of edge weights can add valuable insights in the spreading processes within trade networks and may identify factors influencing the final epidemic size. The aim of the study was to evaluate the effect of different network versions on the outcome of an epidemiological model. The weighted network versions included the number of trade contacts (A), the sum of delivered livestock (B) and the mean number of delivered livestock per trade contact (C). Furthermore, other factors, e.g. transmission probability and farm type of primary outbreak, were tested for their impact on the final epidemic size. From 2013–2014, data from a pig trade network in Northern Germany was recorded containing 678 farms connected by 1,018 directed edges. An epidemiological model was implemented considering a higher probability of disease spread for edges with a higher weight for each of the combinations between network version and transmission probability. Only transmission routes following the network structure were considered for disease transmission. The outcome of the epidemiological model (number of infected farms) was tested with a generalized linear mixed model including the fixed effects network version (unweighted, A, B, C), transmission probability and farm type of primary outbreak (breeding farm, farrowing farm, finishing farm, farrow-to-finishing farm, unknown) as well as all twofold interactions. The results revealed that all fixed effects as well as all twofold interactions were significant (p ≤ 0.05), i.e. in the following only the impact of the interactions on the number of infected farms can be interpreted. Network versions B and C showed in all combinations the highest number of infected farms independent of the underlying transmission probability. The unweighted network and network version A showed a significant increase of infected farms with increasing transmission probability. All interactions including the farm type of primary outbreak revealed a significant higher number of infected farms for farm types located at the beginning of the production chain, e.g. breeding farms. These farm types reached also more other farms in 1–4 steps compared to farm types located near to the end of the production chain. The inclusion of edge weights has a significant effect on the outcome of epidemiological models and dependent on the chosen edge weight the results need to be interpreted accordingly.

INFLUENCE OF FIRE PARTITIONS FOR SPEED FIRE DISTRIBUTION IN CLOSED PREMISES OF PRODUCTION AND STORAGE FACILITIES

Introduction. Fires in closed premises of production and storage facilities are the most dangerous, because they hold large areas with a significant fire load. The current direction of providing a fire safety system at production and storage facilities in closed premises is to eliminate the conditions of the rapid development of fire and minimizing its effect through the use of fire curtains. This method of fire protection is practically not used in closed premises of production and storage facilities at the present stage. In most cases, fire partitions are used in such situations. Therefore, a topic issue today is the research of limiting the development of fires with the use of fire partitions and minimizing fire effects.Purpose. Investigate the process of spreading the fire in closed premises of production and storage facilities by using fire partitions to limit the speed of fire spread. Problem statement and solution. The following tasks must be solved to provide fire protection of production and storage facilities:1. to investigate the process of fire spread in closed premises of production and storage facilities without the use of fire partitions;2. to investigate the impact of fire partitions use on fire rate.Two possible modes of development fire in the premises are considered to solve the first problem: 1) with the presence of sufficient air (oxygen), with fire occurred in regulated fire load; 2) with insufficient air (oxygen), with fire occurred in regulated ventilation.It is necessary to choose the material and fire partition design accordingly to solve the second problem. The results of experimental studies [11] showed that fire partitions vermiculite-silicate plates can be used for various building structures manufacturing. Closed production and storage facilities structure analysis showed that these premises are constructed in most cases with a grid of columns 9Х12 m.Conclusions and proposals:1) There is only the first mode of fire with sufficient oxygen (air) in closed premises of production and storage facilities with a total area of more than 5000 m2 in the process of fire. The fire that occurred is regulated only by the fire load.2) The use of fire partitions between sections of the premises of production and storage facilities reduces the probability of fire spreading in the premises by about 3 times.3) It is necessary to continue research work in this direction to obtain more significant results of the process of development and spread of fire in the premises of production and storage facilities.