Mixing Patterns

The effect of slurry mixing in an anaerobic digester on biogas production was intensively studied in the last few years. This subject is still debatable due to fact that this process involves three phases, solid-gas-liquid, along with the involvement of microbes during biochemical reactions, which are highly vulnerable to changes in hydrodynamic shear stresses and mixing conditions. Moreover, the complexity in the direction of optimization of mixing magnifies due to the implication of both fluid mechanics and biochemical engineering to study the effect of mixing in anaerobic digestion (AD). The effect of mixing on AD is explored using recent literature and theoretical analysis, concentrating on the multi-phase and multi-scale aspects of AD. The tools and methods available to experimentally quantify the function of mixing on both the global and local scales are summarized in this study. The major challenge for mixing in an anaerobic digester is to minimize dead zones and maintain uni...

This paper is a critical evaluation of the effect of mixing on biogas production rates in an anaerobic digester. Mixing plays a prominent role in determining the efficiency of the anaerobic digestion process. This review analyzes the miscellaneous effects of mixing (on the microbial community, methane content and volatile fatty acids) at various mixing intensities and during different stages of the digestion process. Intermittent mixing (mixing at intervals) seems preferable in terms of the quality and quantity of biogas produced, and results in lower power consumption and maintenance costs associated with large-scale biogas production. Preferable mixing time (the length at intervals) and the intensity depends on the geometry of the digester and impeller. The conclusion is drawn that the study of the slurry rheology is very crucial in the designing of the mixing equipment, the shape and size of the digester, and the pipe transport system which can assist in minimizing the initial investment and operational costs. Accordingly, this paper focuses on the parameters which determine the potency of mixing, such as viscosity, total solid content and digester design. Empirical data demonstrated by various researchers regarding rheological characteristics is compared and reviewed. Consequently, close attention should be paid toward the optimization of mixing in terms of its speed, mixing time and impeller geometry, especially during different stages of the digestion process (hydrolysis, acidogenesis, acetogenesis and methanogenesis). Finally, readers will be guided to the extensive publications regarding optimization, directions of future research, and troubleshooting of the mixing operation in an anaerobic digester. This investigation will help to improve mixing efficiency with biogas plants. Effect of shear rate on different stages of an anaerobic digestion process. Methane content varies with the variation in mixing speeds. Mixing effect is significant when the total solid content is higher. Intermittent mixing is favorable when compared to continuous mixing. The geometry of the digester and mixer is essential to evaluate digester mixing.

Significance A central theme of network science is the heterogeneity present in real-life systems, for instance through the absence of a characteristic degree for the nodes. Despite their small-worldness, networks may present other types of heterogeneous patterns, with different parts of the network exhibiting different behaviors. Here we focus on assortativity, a network analogue of correlation used to describe how the presence and absence of edges covaries with the properties of nodes. We design a method to characterize the heterogeneity and local variations of assortativity within a network and exhibit, in a variety of empirical data, rich mixing patterns that would be obscured by summarizing assortativity with a single statistic.

This article studies the dynamics of the development of legal term abbreviations used in the discourse of modern English and
Uzbek languages and their structural classification. In this work, the abbreviation is structurally described according to the
universality of the model of formation of terms as well as in accordance with the universality of the formation model. The
abbreviated lexical units of this speech are divided and analyzed as follows: initial (abbreviations consisting of letters and
sounds); syllabic (apocopes, apheresis, synchronization, contractures); complex syllabic (original mixed syllable, additions); a
mixed abbreviation.
Here is stated that the most commonly used abbreviations in English legal discourse are initials and acronyms, and the
least used abbreviations are (cross-sections) hyphens and mixed types. Also, it is determined that abbreviations are mainly used
in written speech and are not typical for oral speech.

Microalgae are fast growing photoynthetic microorganisms and it have very wide range of industrial applications such as biofuels and wastewater treatment. These cells can be grown in a wide variety of systems ranging from open culture systems (e.g., ponds) to closed culture systems of photobioreactor (e.g., airlift). The open culture systems exist in the external environment, and hence, are not intrinsically controllable. However, the microalgae production in enclosed photobioreactors faces prohibitively high production costs with special difficulty in reactor design and scale-up. The light availability and utilization efficiency in the photobioreactor in terms of design and scale-up consider as the major problem in this system. It has been found that hydrodynamics and mixing can significantly improve the biomass yield by enhanced the light use efficiency. However, the hydrodynamics analysis, and their interacts with photosynthesis in real culturing system is remain unclear. The overall objective of this study is to advance the understanding of hydrodynamics' role in the photosynthesis and thus the photobioreactor performance. The local flow dynamics in a split internal-loop photobioreactor were study by applied a sophisticated Radioactive Particle Tracking (RPT) and advanced Computer Tomography (CT) techniques. Based on the findings, fundamentally based dynamic modeling approach is developed for photobioreactor performance evaluation, which integrates the knowledge of photosynthesis, hydrodynamics, and irradiance. Finally, Scenedesmus sp. was grown in split column. The biomass concentrations, flow dynamics, physical properties, and irradiance distribution of the culturing systems were monitored. Good agreements between the predictions by the developed dynamic model and the experimental data were achieved, indicating the applicability of the dynamic model in industrial interested condition. v ACKNOWLEDGMENTS After a journey of research effort and diligence culminated in the completion of this work, my praises and thanks are to Allah Almighty for his grace and blessing to me. I wish to express my sincerest thanks and gratitude to my advisor Prof. Muthanna Al-Dahhan for his considerable efforts, advice, guidance, encouragement, and support throughout my Ph.D. study, which helped me to overcome many obstacles, and his critical review of my papers significantly enhanced my skills. I am also extending my sincere thanks to all members of my committee, Dr. Joseph Smith, Dr. Daniel Forciniti, Dr. Fatih Dogan, Dr. Shoaib Usman, and Dr. Joontaek Park, for examining my dissertation and enriching it with valuable tips and guidance that help to make it the best. I want to express my gratitude to my sponsor, Ministry of Higher Education in Iraq, for awarding me a fully funded scholarship and for their friendly assistance throughout my Ph.D. study. I would like to gratefully thank my lab-mate, and my lifetime friend, Abbas Sultan, for his valuable assistance and insightful discussions and suggestions. I appreciatively would like to thank my research group members. My special thanks and appreciation also goes to Dr.

Background Most countries have enacted some restrictions to reduce social contacts to slow down disease transmission during the COVID-19 pandemic. For nearly two years, individuals likely also adopted new behaviours to avoid pathogen exposure based on personal circumstances. We aimed to understand the way in which different factors affect social contacts – a critical step to improving future pandemic responses. Methods The analysis was based on repeated cross-sectional contact survey data collected in a standardized international study from 21 European countries between March 2020 and March 2022. We calculated the mean daily contacts reported using a clustered bootstrap by country and by settings (at home, at work, or in other settings). Where data were available, contact rates during the study period were compared with rates recorded prior to the pandemic. We fitted censored individual-level generalized additive mixed models to examine the effects of various factors on the number o...

Assortativity by degree for complex networks is quantified by the Newman coefficient, and it describes a tendency for nodes to be connected to others with a similar degree. A generalization of the assortativity index has been proposed in the literature for undirected and unweighted networks, analysing the correlation between vertices that are not necessarily adjacent, but connected through paths, shortest paths and random walks. The aim of this study is to define a new class of higher-order assortativity measures for weighted networks. The effectiveness of these measures is evident in social networks, where both weights and connections are significant. Applications to Facebook and co-authorship networks are provided, analysing the assortativity beyond the nearest neighbours.

Assortativity by degree for complex networks is quantified by the Newman coefficient, and it describes a tendency for nodes to be connected to others with a similar degree. A generalization of the assortativity index has been proposed in the literature for undirected and unweighted networks, analysing the correlation between vertices that are not necessarily adjacent, but connected through paths, shortest paths and random walks. The aim of this study is to define a new class of higher-order assortativity measures for weighted networks. The effectiveness of these measures is evident in social networks, where both weights and connections are significant. Applications to Facebook and co-authorship networks are provided, analysing the assortativity beyond the nearest neighbours.

The emerging field of the Science of Cities has revealed universal power-law trends in urban scaling, transcending cultural and geographic variations. This study investigates the interplay between fundamental allometry, fractal dimensions, and city social dynamics. By linking these factors to the hierarchical social structures defined by Dunbar’s numbers, a causal relationship is established that illuminates the drivers of urban scaling. Notably, this research highlights the pivotal role of the Big Five personality traits in shaping the fractal nature of urban environments. These findings bridge the gap between human cognitive traits and urban structural patterns, offering a novel perspective on the universality of urban scaling and opening new opportunities for interdisciplinary exploration.

Infectious disease transmission models often stratify populations by age and geographic patches. Contact patterns between age groups and patches are key parameters in such models. Arenas et al. (2020) develop an approach to simulate contact patterns associated with recurrent mobility between patches, such as due to work, school, and other regular travel. Using their approach, mixing between patches is greater than mobility data alone would suggest, because individuals from patches A and B can form a contact if they meet in patch C. We build upon their approach to address three potential gaps that remain. First, our approach includes a distribution of contacts by age that is responsive to underlying age distribution of the mixing pool. Second, different age distributions by contact type are also maintained in our approach, such that changes to the numbers of different types of contacts are appropriately reflected in changes to the overall age mixing patterns. Finally, we introduce an...

air pollution and adverse birth outcomes. Methods: We systematically searched for meta-analyses on criteria air pollutants (NO 2 , CO, O 3 , SO 2 , and PM 2.5 and PM 10 ) and adverse birth outcomes (preterm birth, stillbirth, reduced birth weight, low birth weight, and small-for-gestational age) from PubMed, CINAHL, Scopus, MEDLINE/Ovid, EMBASE/Ovid, Web of Science, systematic reviews repositories, electronic grey literature, and references on 21 st September 2020 with weekly alerts thereafter. We graded the overall direction and confidence of cause-and-effect as per our pre-specified protocol (Doi:10.3390/ijerph17228658). Results: Sixteen (16) meta-analyses, pooling 192 unique primary studies with moderate (9.0%) overlap qualified for the final synthesis. Consistent positive associations were reported between whole pregnancy exposure to PM 2.5 /PM 10 and birth weight reduction and between CO/SO 2 and low birth weight and were graded as strong ( þþ). There were less consistent associations between whole pregnancy PM 2.5 /NO 2 exposures with PTB, and for all criteria pollutants with stillbirth, hence graded moderate (þ). Evidence for associations with trimester specific exposures were also moderate (þ). However, meta-analyses observed high heterogeneity, high imprecision, and lacked experimental studies. Consequently, taken together, the current observations indicate 'probable evidence' of causation. Conclusions: Current observations indicate 'probable evidence' of causation. Further studies with standardised designs would help elucidate reasons for heterogeneity of associations. Key messages: In the absence of randomised controlled trials, the strong observational evidence for associations between ambient air pollution and adverse birth outcomes warrants adoption of the precautionary principle.

Understanding age-mixing patterns in Human Immunodeficiency Virus (HIV) transmission networks can enhance the design and implementation of HIV prevention strategies in sub-Saharan Africa. Due to ethical consideration, it is less likely possible to conduct a benchmark study to assess which sampling strategy, and sub-optimal sampling coverage which can yield best estimates for these patterns. We conducted a simulation study, using phylogenetic trees to infer estimates of age-mixing patterns in HIV transmission, through the computation of proportions of pairings between men and women, who were phylogenetically linked across different age groups (15–24 years, 25–39 years, and 40–49 years); and the means, and standard deviations of their age difference. We investigated also the uncertainty around these estimates as a function of the sampling coverage in four sampling strategies: when missing sequence data were missing completely at random (MCAR), and missing at random (MAR) with at most ...

Community mixing patterns by sociodemographic traits can inform the risk of epidemic spread among groups, and the balance of in-and out-group mixing affects epidemic potential. Understanding mixing patterns can provide insight about potential transmission pathways throughout a community. We used a snowball sampling design to enroll people recently diagnosed with SARS-CoV-2 in an ethnically and racially diverse county and asked them to describe their close contacts and recruit some contacts to enroll in the study. We constructed egocentric networks of the participants and their contacts and assessed agemixing, ethnic/racial homophily, and gender homophily. The total size of the egocentric networks was 2,544 people (n = 384 index cases + n = 2,160 recruited peers or other contacts). We observed high rates of in-group mixing among ethnic/racial groups compared to the ethnic/racial proportions of the background population. Black or African-American respondents interacted with a wider range of ages than other ethnic/racial groups, largely due to familial relationships. The egocentric networks of non-binary contacts had little age diversity. Black or African-American respondents in particular reported mixing with older or younger family members, which could increase the risk of transmission to vulnerable age groups. Understanding community mixing patterns can inform infectious disease risk, support analyses to predict epidemic size, or be used to design campaigns such as vaccination strategies so that community members who have vulnerable contacts are prioritized.

This study aimed to analyze the types of code mixing, especially those found on WhatsApp social media made by bilingual immigrants of Pakistan in everyday life. The descriptive methodology was utilized by the researchers to carry out this study, which concentrated on code mixing. This study examined how English was used by immigrants to connect with friends in Malaysia, Indonesia, and other countries as well as with friends who were also immigrants from Pakistan who were living in Makassar. Research subject has been living in Makassar for three years. Data obtained through observation on the WhatsApp of Bilingual Immigrant account. In order to assess the data, Hoffman's (1991) theory was used. Data analysis revealed that there were five instances of "Intra-Sentential" code-mixing, five instances of "Intralexical" code-mixing, and zero instances of code-mixing "involving a change of pronunciation".

BackgroundNear 60% of new HIV infections in the United Kingdom are estimated to occur in men who have sex with men (MSM). Patterns of mixing between different risk groups of MSM have been suggested to spread the HIV epidemics through age-disassortative partnerships and to contribute to ethnic disparities in infection rates. Understanding these mixing patterns in transmission can help to determine which groups are at a greater risk and guide prevention.MethodsWe analyzed combined epidemiologic data and viral sequences from MSM diagnosed with HIV as of mid-2015 at the national level. We applied a phylodynamic source attribution model to infer patterns of transmission between groups of patients by age, ethnicity and region.ResultsFrom pair probabilities of transmission between 19 847 MSM patients, we found that potential transmitters of HIV subtype B were on average 5 months older than recipients. We also found a moderate overall assortativity of transmission by ethnic group and a stro...

IntroductionUnderstanding human mixing patterns relevant to infectious diseases spread through close contact is vital for modelling transmission dynamics and optimisation of disease control strategies. Mixing patterns in low-income countries like Malawi are not well understood.MethodologyWe conducted a social mixing survey in urban Blantyre, Malawi between April and July 2021 (between the 2nd and 3rd wave of COVID-19 infections). Participants living in densely-populated neighbourhoods were randomly sampled and, if they consented, reported their physical and non-physical contacts within and outside homes lasting at least 5 minutes during the previous day. Age-specific mixing rates were calculated, and a negative binomial mixed effects model was used to estimate determinants of contact behaviour.ResultsOf 1,201 individuals enrolled, 702 (58.5%) were female, the median age was 15 years (interquartile range [IQR] 5-32) and 127 (10.6%) were HIV-positive. On average, participants reported...

Data relating to contact mixing patterns among humans are essential for the accurate modeling of infectious disease transmission dynamics. Here, we describe contact mixing patterns among migrant workers in urban settings in Thailand, based on a survey of 369 migrant workers of three nationalities. Respondents recorded their demographic data, including age, sex, nationality, workplace, income, and education. Each respondent chose a single day to record their contacts; this resulted in a total of more than 8300 contacts. The characteristics of contacts were recorded, including their age, sex, nationality, location of contact, and occurrence of physical contact. More than 75% of all contacts occurred among migrants aged 15 to 39 years. The contacts were highly clustered in this age group among migrant workers of all three nationalities. There were far fewer contacts between migrant workers with younger and older age groups. The pattern varied slightly among different nationalities, whi...

M ixing behavior of three geometrically equivalent 0.06 m 3 bubble column and airlift photobioreactors was compared for use in microalgal culture. Mixing was characterized in terms of the axial dispersion coefficient, mixing time, circulation time and Bodenstein number. Measurements were reported in tap water and sea water, as used in growing microalgal biomass. Compared with the two airlift reactors (a split-cylinder and a draft-tube sparged device, both of aspect ratio 9.1), the bubble column (aspect ratio ¼ 9.1) had a shorter mixing time at any aeration rate (superficial aeration velocity of up to 0.05 m s 21 in all reactors). Values of the various mixing parameters in the two fluids were quite comparable at identical aeration rates in any specific geometry of the reactors. Existing correlations of mixing times satisfactorily correlated the data in the bubble column, but not in the airlift reactors. The following correlations were established for the airlift devices: Bo LG ¼ b(Fr 1=3) l Bo ¼ k t m t c where Bo is the liquid-phase Bodenstein number, Fr is the Froude number, Bo LG is the Bodenstein number based on the superficial velocity of the gas, t m is the mixing time, t c is the circulation time, and k, b and g are constants that depend on the geometry of the reactor and the fluid used.

The effect of slurry mixing in an anaerobic digester on biogas production was intensively studied in the last few years. This subject is still debatable due to fact that this process involves three phases, solid-gas-liquid, along with the involvement of microbes during biochemical reactions, which are highly vulnerable to changes in hydrodynamic shear stresses and mixing conditions. Moreover, the complexity in the direction of optimization of mixing magnifies due to the implication of both fluid mechanics and biochemical engineering to study the effect of mixing in anaerobic digestion (AD). The effect of mixing on AD is explored using recent literature and theoretical analysis, concentrating on the multi-phase and multi-scale aspects of AD. The tools and methods available to experimentally quantify the function of mixing on both the global and local scales are summarized in this study. The major challenge for mixing in an anaerobic digester is to minimize dead zones and maintain uni...

Mathematical and computational modeling approaches are increasingly used as quantitative tools in the analysis and forecasting of infectious disease epidemics. The growing need for realism in addressing complex public health questions is, however, calling for accurate models of the human contact patterns that govern the disease transmission processes. Here we present a data-driven approach to generate effective population-level contact matrices by using highly detailed macro (census) and micro (survey) data on key socio-demographic features. We produce age-stratified contact matrices for 35 countries, including 277 sub-national administratvie regions of 8 of those countries, covering approximately 3.5 billion people and reflecting the high degree of cultural and societal diversity of the focus countries. We use the derived contact matrices to model the spread of airborne infectious diseases and show that sub-national heterogeneities in human mixing patterns have a marked impact on e...

SIR model is one of the simplest methods used in prediction of endemic/pandemic outbreaks. We examined SIRD model for development of COVID-19 in Kuwait which was started on 24 February 2020 by 5 patients in Kuwait. This paper investigates sensitivity of SIRD model for development of COVID-19 in Kuwait based on duration of progressed days of data. For Kuwait, we have fitted SIRD model to COVID-19 data for 20, 40, 60, 80, 100, and 116 days of data and assessed sensitivity of the model with number of days of data. The parameters of SIRD model are obtained using an optimization algorithm (lsqcurvefit) in MATLAB. The total population of 50,000 is equally applied for all Kuwait time intervals. Results of SIRD model indicates that after 40 days the peak infectious day can be adequately predicted; althogh, error percentage from sensetivity analysis indicates that different exposed population sizes are not correctly predicted. SIRD type models are too simple to robustly capture all features ...

Background: Contact surveys and diaries have conventionally been used to measure contact networks in different settings for elucidating infectious disease transmission dynamics of respiratory infections. More recently, technological advances have permitted the use of wireless sensor devices, which can be worn by individuals interacting in a particular social context to record high resolution mixing patterns. To date, a direct comparison of these two different methods for collecting contact data has not been performed. Methods: We studied the contact network at a United States high school in the spring of 2012. All school members (i.e., students, teachers, and other staff) were invited to wear wireless sensor devices for a single school day, and asked to remember and report the name and duration of all of their close proximity conversational contacts for that day in an online contact survey. We compared the two methods in terms of the resulting network densities, nodal degrees, and degree distributions. We also assessed the correspondence between the methods at the dyadic and individual levels. Results: We found limited congruence in recorded contact data between the online contact survey and wireless sensors. In particular, there was only negligible correlation between the two methods for nodal degree, and the degree distribution differed substantially between both methods. We found that survey underreporting was a significant source of the difference between the two methods, and that this difference could be improved by excluding individuals who reported only a few contact partners. Additionally, survey reporting was more accurate for contacts of longer duration, and very inaccurate for contacts of shorter duration. Finally, female participants tended to report more accurately than male participants. Conclusions: Online contact surveys and wireless sensor devices collected incongruent network data from an identical setting. This finding suggests that these two methods cannot be used interchangeably for informing models of infectious disease dynamics.

Multilingual individuals, who possess proficiency in multiple languages and an understanding of their structures, often engage in code-mixing as a means of communication. This study aims to explore the code-mixing patterns exhibited by Yahukimo students residing in Malang, as well as the underlying motivations for their code-mixing practices. Employing a descriptive qualitative research design, the study identifies two predominant types of code-mixing: insertion and congruent lexicalization, which are influenced by the linguistic structures of the languages involved. Additionally, the variation in code-mixing is classified into inner and outer code-mixing. The findings indicate that Yahukimo students employ code-mixing as a means of fostering solidarity and navigating social and cultural distances. This research provides valuable insights into the intricate dynamics of language use and contributes to our understanding of the phenomenon of code-mixing

This paper presents mathematical modeling and quantitative evaluation of Large Scale Social Restriction (LSSR) in Jakarta between 10 April and 4 June 2020. The special capital region of Jakarta is the only province among 34 provinces in Indonesia with an average Testing Positivity Rate (TPR) below 5% recommended by the World Health Organization (WHO). The transmission model is based on a discrete-time compartmental epidemiological model incorporating suspected cases. The quantitative evaluation is measured based on the estimation of the time-varying effective reproduction number (ℛt). Our results show the LSSR has been successfully suppressed the spread of COVID-19 in Jakarta, which was indicated by ℛt < 1. However, once the LSSR was relaxed, the effective reproduction number increased significantly. The model is further used for short-term forecasting to mitigate the course of the pandemic.

First, we study the effects of behavioral changes in a smallpox attack model. Response strategies to a smallpox bioterrorist attack have focused on interventions such as isolation, contact tracing, quarantine, ring vaccination, and mass vaccina tion. We formulate and analyze a mathematical model in which some individuals lower their daily contact activity rates once an epidemic has been identified in a community. We use computer simulations to analyze the effects of behavior change alone and in combination with other control measures. We demonstrate that the spread of the disease is highly sensitive to how rapidly people reduce their contact activity. Next, we study mixing patterns between age groups using social networks.

Anaerobic hydrogen production (AHP) is a biochemical process capable of producing hydrogen and fatty acids from organic substrates in acidogenic phase. Currently, almost all of anaerobic systems use centrally stirred mixing where the flow is essentially rotated uniformly in the radial direction. Given the high energy requirement of mixing and the urgent needs for enhancing the contact between microbial particles and substrates, a new type of mixing strategy should be developed. This study focused on the enhancement of biogas production and organic removal efficiency in AHP systems through a novel chaotic mixing regime. The stirring impeller was operated eccentrically with the stirring center eccentrically located 2 and 4 cm off the center, respectively and at different heights (5, 10.5 and 16 cm). The eccentrically stirred mixing was expected to enhance the mixing efficiency and accelerate the contact between biomass and organic substrates in the AHP system. A numerical finite element model was developed to simulate the flow patterns and the biomass distribution, through which the Lyapunov exponent λ values were calculated in order to assess the strength of eccentrically stirred mixing at different mixing eccentricities. The model simulations showed that at the height of 10.5 and 16 cm, the Lyapunov exponent λ increased as the mixing eccentricity increased. This corresponded well with the experimental results, which showed that the organic removal efficiency and biogas production increased with the mixing eccentricity. Compared with centrally stirred mixing, eccentrically stirred mixing enhanced the interaction of flow and biomass particles and ultimately enhanced the biogas production and organic removal in AHP systems.

This report presents a technical description of our agent-based epidemic model of a particular middle-sized municipality. We have developed a realistic model with 56 thousand inhabitants and 2.7 millions of social contacts. These form a multi-layer social network that serves as a base of our epidemic simulation. The disease is modeled by our extended SEIR model with parameters fitted to real epidemics data for Czech Republic. The model is able to simulate a whole range of non-pharmaceutical interventions on individual level, such as protective measures and physical distancing, testing, contact tracing, isolation and quarantine. The effect of government-issued measures such as contact restrictions in different environments (schools, restaurants, vendors, etc.) can also be simulated.The model is implemented in Python and is available as open source at:www.github.com/epicity-cz/model-m/releases

In the contemporary world of global business and continuously growing competition, organizations tend to use mergers and acquisitions to enforce their position on the market. The future organization's design is a critical success factor in such undertakings. The field of social network analysis can enhance our uderstanding of these processes as it lets us reason about the development of networks, regardless of their origin. The analysis of mixing patterns is particularly useful as it provides an insight into how nodes in a network connect with each other. We hypothesize that organizational networks with compatible mixing patterns will be integrated more successfully. After conducting a simulation experiment, we suggest an integration model based on the analysis of network assortativity. The model can be a guideline for organizational integration, such as occurs in mergers and acquisitions.

This paper presents mathematical modeling and quantitative evaluation of Large Scale Social Restriction (LSSR) in Jakarta between 10 April and 4 June 2020. The special capital region of Jakarta is the only province among 34 provinces in Indonesia with an average Testing Positivity Rate (TPR) below 5% recommended by the World Health Organization (WHO). The transmission model is based on a discrete-time compartmental epidemiological model incorporating suspected cases. The quantitative evaluation is measured based on the estimation of the time-varying effective reproduction number (ℛt). Our results show the LSSR has been successfully suppressed the spread of COVID-19 in Jakarta, which was indicated by ℛt < 1. However, once the LSSR was relaxed, the effective reproduction number increased significantly. The model is further used for short-term forecasting to mitigate the course of the pandemic.

Approximating 'real' disease transmission networks through genomic sequence comparisons among pathogenic isolates is increasingly feasible with the current growth in genomic sequence data. Here, we derive a network from over 4,200 globally distributed influenza A virus isolates based on alignment-free sequence comparisons. We then employ network mixing pattern analysis to examine transmission probabilities between isolates from different global regions, host types, subtypes and collection years. While we can not use our results to describe the complete global network of influenza A virus, we present a novel analytical process. In addition, we describe some of the characteristics of this subset of currently available data. Most notable results are the high levels of inter regional links and the important role that avian species seem to play in non human global transmission.

Coronavirus disease 2019 (covid-19), with the fatality rate in elder (60 years old or more) being much higher than young (60 years old or less) patients, was declared a pandemic by the World Health Organization on March 11, 2020. Taking into account this age-dependent fatality rate, a mathematical model considering young and elder subpopulations was formulated based on the natural history of covid-19 to study the transmission of the SARS-CoV-2. This model can be applied to study the epidemiological scenario resulting from the adoption of isolation or lockdown in many countries to control the rapid propagation of covid-19. We chose as examples the isolation adopted in São Paulo State (Brazil) in the early phase but not at the beginning of the epidemic, and the lockdown implemented in Spain when the number of severe covid-19 cases was increasing rapidly. Based on the data collected from São Paulo State and Spain, the model parameters were evaluated and we obtained higher estimation fo...

BackgroundThe increasing availability of data on social contact patterns and time use provides invaluable information for studying transmission dynamics of infectious diseases. Social contact data provide information on the interaction of people in a population whereas the value of time use data lies in the quantification of exposure patterns. Both have been used as proxies for transmission risks within in a population and the combination of both sources has led to investigate which kind of social encounters are most relevant to describe transmission risk.MethodsWe used social contact and time use data from 1707 participants from a survey conducted in Flanders, Belgium in 2010-2011. We calculated weighted exposure time and social contact matrices to analyze age- and gender-specific mixing patterns and to quantify behavioral changes by distance from home. We compared the value of both data sources, individually and combined, for explaining seroprevalence and incidence data on parvovi...

The present study aimed to investigate and compares the pattern of Code Mixing in Sequential bilingual young adult. Thirty Sequential bilingual (Tamil-English) adults between the age range of 18-25 years were participated in this study. The bilingual participants were asked to describe the cookie-theft picture in Tamil. The patterns of Code Mixing (Intra Sentential Mixing and Intra Lexical Mixing) were analysed from the collected data. The results showed sequential bilingual adult uses 4.8% of Intra Sentential Mixing and 5.3% of Intra Lexical Mixing. In pattern of Code Mixing, Intra Sentential Mixing found to more in women. The present study concluded that Sequential bilingual speaker uses slightly higher percentage of Intra Lexical Mixing when compared to Intra Sentential Mixing in the picture description task. This finding will help Speech Language Pathologist to plan assessment, intervention and to development appropriate material for Sequential bilingual speakers in making clinical decision.

Understanding infection dynamics of respiratory diseases requires the identification and quantification of behavioural, social and environmental factors that permit the transmission of these infections between humans. Little empirical information is available about contact patterns within real-world social networks, let alone on differences in these contact networks between populations that differ considerably on a socio-cultural level. Here we compared contact network data that were collected in the Netherlands and Thailand using a similar online respondent-driven method. By asking participants to recruit contact persons we studied network links relevant for the transmission of respiratory infections. We studied correlations between recruiter and recruited contacts to investigate mixing patterns in the observed social network components. In both countries, mixing patterns were assortative by demographic variables and random by total numbers of contacts. However, in Thailand participants reported overall more contacts which resulted in higher effective contact rates. Our findings provide new insights on numbers of contacts and mixing patterns in two different populations. These data could be used to improve parameterisation of mathematical models used to design control

Coronavirus Disease 2019 (COVID-19) started in Wuhan province of China in November 2019 and within a short time, it was declared as a worldwide pandemic by the World Health Organisation due to the very fast worldwide spread of the virus. There were a few studies that look for the correlation with infected individuals and different environmental parameters using early data of COVID-19 but there was no study that deal with the variation of effective reproduction number and environmental factors. Effective reproduction number is the driving parameter of the spread of a pandemic and it is important to study the effect of various environmental factors on effective reproduction numbers to understand the effect of those factors on the spread of the virus. We have used time-dependent models to investigate the variation of different time-dependent driving parameters of COVID-19 like effective reproduction number and contact rate using data from India as a test case. India is a large populati...

This paper presents mathematical modeling and quantitative evaluation of Large Scale Social Restriction (LSSR) in Jakarta between 10 April and 4 June 2020. The special capital region of Jakarta is the only province among 34 provinces in Indonesia with an average Testing Positivity Rate (TPR) below 5% recommended by the World Health Organization (WHO). The transmission model is based on a discrete-time compartmental epidemiological model incorporating suspected cases. The quantitative evaluation is measured based on the estimation of the time-varying effective reproduction number (ℛt). Our results show the LSSR has been successfully suppressed the spread of COVID-19 in Jakarta, which was indicated by ℛt < 1. However, once the LSSR was relaxed, the effective reproduction number increased significantly. The model is further used for short-term forecasting to mitigate the course of the pandemic.

Social mixing patterns are key determinants of infectious disease transmission. Mathematical models parameterised with empirical data from contact pattern surveys have played an important role in understanding epidemic dynamics and informing control strategies, including for SARS-CoV-2. However, there is a paucity of data on social mixing patterns in many settings. We conducted a community-based survey in Cambodia to characterise mixing patterns and generate setting-specific contact matrices according to age and urban/rural populations. Data were collected using a diary-based approach from 2,004 participants, selected by stratified random sampling. Contact patterns were highly age-assortative, with clear intergenerational mixing between household members. Both home and school were high-intensity contact settings, with 27.7% of contacts occurring at home with non-household members. Social mixing patterns differed between rural and urban residents; rural participants tended to have mo...

Social mixing patterns are key determinants of infectious disease transmission. Mathematical models parameterised with empirical data from contact pattern surveys have played an important role in understanding epidemic dynamics and informing control strategies, including for SARS-CoV-2. However, there is a paucity of data on social mixing patterns in many settings. We conducted a community-based survey in Cambodia to characterise mixing patterns and generate setting-specific contact matrices according to age and urban/rural populations. Data were collected using a diary-based approach from 2,004 participants, selected by stratified random sampling. Contact patterns were highly age-assortative, with clear intergenerational mixing between household members. Both home and school were high-intensity contact settings, with 27.7% of contacts occurring at home with non-household members. Social mixing patterns differed between rural and urban residents; rural participants tended to have mo...

BackgroundThe coronavirus 2019 (COVID-19) pandemic has caused significant changes to homes, working life and stress. The purpose of this research was to investigate the implications that the COVID-19 pandemic has had on the menstrual cycle and any contributing factors to these changes.MethodsA questionnaire was completed by 749 participants, whom ranged from ‘physically active’ to elite, in their training status. The questionnaire captured detail on menstrual cycle symptoms and characteristics prior to and during the COVID-19 pandemic lockdown period, as well as lifestyle, stress, exercise and nutrition. Descriptive statistics and frequency distribution were reported and decision tree analysis performed. Statistical significance was assumed at p<0.05.ResultsFifty-two point six percent of females experienced a change in their menstrual cycle during the lockdown period. Psychosocial symptoms had changed in over half of all participants. Participants who reported increased stress/wo...

Owing to the SARS-CoV-2 epidemic (severe acute respiratory coronavirus 2 syndromes), the global situation has changed drastically. Several countries, including India, Europe, U.S.A., introduced a full state/nation lockdown to minimize the disease transmission through human interaction after the virus entered the population and to minimize the loss of human life. Millions of people have gone unemployed due to lockdown implementation, resulting in business and industry closure and leading to a national economic slowdown. Therefore, preventing the spread of the COVID-19 virus in the world while also preserving the global economy is an essential problem requiring an effective and immediate solution. Using the compartmental epidemiology S, E, I, R or D (Susceptible, Exposed, Infectious, Recovery or Death) model extended to multiple population regions we predict the evolution of the SARS-CoV-2 disease and construct an optimally scheduled lockdown calendar to execute lockdown over phases, ...

The anaerobic digestion (AD) process is influenced by a variety of operation parameters, such as sludge rheology, mixing, temperature, solid retention time (SRT), hydraulic retention time (HRT) and solids concentration. The optimum in the mixing lies somewhere between no-mixing and continuous mixing, as the lack or excessive mixing can lead to poor AD performance instead. A three-dimensional computational fluid dynamics steady/unsteady model, incorporating the rheological properties of the sludge, was developed and applied to quantify mixing in a full-scale anaerobic digester. Mechanical and gas mixing solutions were taken into account, keeping constant the daily energy consumption. Results, consisting of velocity magnitude and patterns, dead zone formation and turbulence levels were discussed. Compared to the mechanical mixing, gas mixing had lower percentage of dead zones (about 5% against 50%), larger maximum velocity (about 3 m/s against 1 m/s) as well as larger turbulent kineti...

Social mixing patterns are key determinants of infectious disease transmission. Mathematical models parameterised with empirical data from contact pattern surveys have played an important role in understanding epidemic dynamics and informing control strategies, including for SARS-CoV-2. However, there is a paucity of data on social mixing patterns in many settings. We conducted a community-based survey in Cambodia to characterise mixing patterns and generate setting-specific contact matrices according to age and urban/rural populations. Data were collected using a diary-based approach from 2,004 participants, selected by stratified random sampling. Contact patterns were highly age-assortative, with clear intergenerational mixing between household members. Both home and school were high-intensity contact settings, with 27.7% of contacts occurring at home with non-household members. Social mixing patterns differed between rural and urban residents; rural participants tended to have mo...