scholarly journals An agent-based algorithm resembles behaviour of tree-dwelling bats under fission–fusion dynamics

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ján Zelenka ◽  
Tomáš Kasanický ◽  
Ivana Budinská ◽  
Peter Kaňuch
Keyword(s):  
Local Population ◽  
Agent Based ◽  
Nyctalus Leisleri ◽  
Simulated Environment ◽  
Switching Dynamics ◽  
Decision Making Processes ◽  
The Mean ◽  
Swarm Algorithm ◽  
Number Of Individuals ◽  
Habitat Parameters

Abstract Utilization of computational approach in the study of social behaviour of animals is increasing and we attempted such an approach in our study of tree-dwelling bats. These bats live in highly dynamic fission–fusion societies that share multiple roosts in a common home range. The key behavioural component associated with complex and non-centralized decision-making processes in roost switching is swarming around potential locations in order to recruit members to the new roost. To understand roost switching dynamics of bat groups in their natural environment, we employed a computational model, the SkyBat, which is based on swarm algorithm, to model this process. In a simulated environment of this agent-based model, we replicated natural fission–fusion dynamics of the Leisler’s bat, Nyctalus leisleri, groups according to predefined species and habitat parameters. Spatiotemporal patterns of swarming activity of agents were similar to bats. The number of simulated groups formed prior to sunrise, the mean number of individuals in groups and the roost height did not differ significantly from data on a local population of bats collected in the field. Thus, the swarm algorithm gave a basic framework of roost-switching, suggesting possible applications in the study of bat behaviour in rapidly changing environments as well as in the field of computer science.

scholarly journals Acute coronary syndrome: which age group tends to delay call for help?

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Ahmed Ayuna ◽  
Ayyaz Sultan
Keyword(s):  
Acute Coronary Syndrome ◽  
Time Delay ◽  
Local Population ◽  
Age Groups ◽  
Age Group ◽  
Teaching Programme ◽  
The Road ◽  
Coronary Syndrome ◽  
The Mean ◽  
Mean Time

Abstract Background Early diagnosis and treatment of ACS can reduce the risk of complications and death. Delay calling for help can increase morbidity and mortality. It is unclear which age group among patients with acute coronary syndrome tend to delay their call for help. Results Our observational retrospective study showed that men and women in their 50s and 40s respectively tend to delay their call for help from symptoms onset. For the former, the mean time delays (590 ± 71.1 min), whereas for the latter it was (1084 ± 120.1 min). Moreover, these groups tend to have a longer time delay between symptoms onset and arrival at the hospital. Among deaths, we observed that the death rate was proportional to the time delay, which is not unexpected. Next step, we plan to perform a qualitative study in the form of questionnaires to target the individuals with a high risk of CVD within these age groups. Conclusion Middle age group of both genders tend to delay their call for help when they experience symptoms of ACS; moreover, regardless of the age, the longer the delay, the higher the mortality rate. The results of this study gave us a better understanding of our local population and will pave the road for a well-structured teaching programme for them to minimise the time delay for calling for help.

scholarly journals Agent-Based Modeling Framework for Electric Vehicle Adoption Transition in Indonesia

2021 ◽  
Vol 12 (2) ◽  
pp. 73
Author(s):  
Dita Novizayanti ◽  
Eko Agus Prasetio ◽  
Manahan Siallagan ◽  
Sigit Puji Santosa
Keyword(s):  
Electric Vehicles ◽  
Data Analytics ◽  
Agent Based Modeling ◽  
Analysis Framework ◽  
Modeling Framework ◽  
Agent Based ◽  
Twitter Data ◽  
Decision Making Processes ◽  
Electric Vehicle Adoption ◽  
Technical Features

Currently, the adoption of electric vehicles (EV) draws much attention, as the environmental issue of reducing carbon emission is increasing worldwide. However, different countries face different challenges during this transition, particularly developing countries. This research aims to create a framework for the transition to EV in Indonesia through Agent-Based Modeling (ABM). The framework is used as the conceptual design for ABM to investigate the effect of agents’ decision-making processes at the microlevel into the number of adopted EV at the macrolevel. The cluster analysis is equipped to determine the agents’ characteristics based on the categories of the innovation adopters. There are 11 significant variables and four respondents’ clusters: innovators, early majority, late majority, and the uncategorized one. Moreover, Twitter data analytics are utilized to investigate the information engagement coefficient based on the agents’ location. The agents’ characteristics which emerged from this analysis framework will be used as the fundamental for investigating the effect of agents’ specific characteristics and their interaction through ABM for further research. It is expected that this framework will enable the discovery of which incentive scheme or critical technical features effectively increase the uptake of EV according to the agents’ specific characteristics.

Sporadic Schwannomatosis: A Systematic Review Following the 2005 Consensus Statement

2018 ◽  
Vol 79 (05) ◽  
pp. 408-415 ◽  
Author(s):  
Jan Victor ◽  
Thibault Poujade ◽  
Nadine Hollevoet ◽  
Gregoire Chick
Keyword(s):  
Systematic Review ◽  
Consensus Statement ◽  
Case Reports ◽  
Case Series ◽  
Spinal Tumors ◽  
The Mean ◽  
Tumor Distribution ◽  
Key Aspects ◽  
Number Of Individuals

Aims To identify the frequency of reports of sporadic schwannomatosis, the types of patients affected, and the nerves affected. Patients and Methods We identified all case reports and case series that reported on patients with sporadic schwannomatosis according to established criteria. Results The initial search yielded 1,597 studies, of which 15 were included. A total of 38 of 55 individuals met the inclusion criteria. The mean age of the patients was 48 years; 41% were male. Thirty-three patients had peripheral nerve tumors, and 17 had spinal tumors. Twelve had tumors in both locations. Tumor distribution was unilateral in 25 of 30 cases (83.3%) and segmental (limited to one limb or five or fewer contiguous segments of the spine) in 28 of 38 cases (73.7%). Conclusion This systematic review quantified the number of individuals who meet the criteria for sporadic schwannomatosis and better described this population to facilitate the classification of neurofibromatosis in regard to the 2005 consensus statement. Unilateral or segmental distribution of nerve tumors are key aspects when dealing with multiple noncutaneous schwannomas without involvement of the vestibular nerve.

scholarly journals Evaluation of the efficacy of neonicotinoid and pyrethroid insecticides in Diaphorina citri Kuwayama (Hemiptera: Liviidae) populations in Colombia

2018 ◽  
Vol 12 (2) ◽  
pp. 358-368
Author(s):  
Augusto Ramírez-Godoy ◽  
Gina Puentes-Pérez ◽  
Hermann Restrepo-Díaz
Keyword(s):  
Tropical Dry Forest ◽  
Dry Forest ◽  
Asian Citrus Psyllid ◽  
Insect Vector ◽  
Diaphorina Citri ◽  
Pyrethroid Insecticides ◽  
Lambda Cyhalothrin ◽  
The Mean ◽  
Number Of Individuals ◽  
Forest Conditions

The Asian citrus psyllid Diaphorina citri is the insect vector of the disease known as huanglongbing (HLB), which is the most devastating disease of citrus crops in the world. The Asian citrus psyllid was officially reported in Colombia in 2007, and a national phytosanitary emergency was declared because of the presence of HLB in 2015. Two different experiments were carried out in two locations (Apulo and Jerusalén, Department of Cundinamarca) in Colombia to evaluate the effectiveness of neonicotinoid (clothianidin, imidacloprid and thiamethoxan) and pyrethroid applications (bifenthrin, deltamethrin and lambda cyhalothrin) on the control of D. citri populations (adults, nymphs and eggs) in ‘Tahiti’ lime trees established under tropical dry forest conditions. In the first experiment, trees were foliarly treated as follows: (1) untreated trees; (2) trees treated with 100 g ha-1 of imidacloprid; (3) trees treated with 60 g ha-1 of bifenthrin; (4) trees treated with 12.5 g ha-1 of deltamethrin and (5) trees treated with a co-formulation of 70 g ha-1 of a neonicotinoid (thiametoxan) and 53 g ha-1 of a pyrethroid (lambda cyhalothrin). In the second experiment, trees were treated with 100 g ha-1 of clothianidin. Foliar insecticide applications were carried out at 0 and 4 weeks after the initiation of treatments (WAT). In the first trial, the control presented a mean number of individuals per flush of ≈1.14, whereas the trees treated with neoinicotinoids and pyrethroids showed 50% fewer individuals (0.53-0.61). For the population of immatures, the number of nymphs was 2.25 nymphs per flush in the control, as compared to 0.82-1.22 individuals observed in the treatments with insecticides. The mean number of eggs was also between 80-100% higher in the control trees (2.37 individuals), as compared to the treated trees (1.14-1.78). In the second trial, the use of clothianidin showed a higher control of eggs. The results suggest that the rotation of neonicotinoids with pyrethroids can be a tool to reduce populations and delay resistance processes in D. citri in citrus trees established under tropical dry forest conditions in Colombia.

scholarly journals Seasonal activity of Dermacentor reticulatus ticks in the era of progressive climate change in eastern Poland

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zbigniew Zając ◽  
Joanna Kulisz ◽  
Aneta Woźniak ◽  
Katarzyna Bartosik ◽  
Adil Khan
Keyword(s):  
Climate Change ◽  
Local Population ◽  
Weather Conditions ◽  
Dermacentor Reticulatus ◽  
Seasonal Activity ◽  
Saturation Deficit ◽  
Annual Basis ◽  
Questing Ticks ◽  
The Mean

AbstractDermacentor reticulatus ticks are one of the most important vectors and reservoirs of tick-borne pathogens in Europe. Changes in the abundance and range of this species have been observed in the last decade and these ticks are collected in areas previously considered tick-free. This may be influenced by progressive climate change. Eastern Poland is an area where the local population of D. reticulatus is one of the most numerous among those described so far. At the same time, the region is characterized by a significant increase in the mean air temperature in recent years (by 1.81 °C in 2020) and a decrease in the average number of days with snow cover (by 64 days in 2020) and in the number of days with frost (by 20 days in 2020) on an annual basis compared to the long-term average. The aim of our research was to investigate the rhythms of seasonal activity and the population size of D. reticulatus in the era of progressive climate change. To this end, questing ticks were collected in 2017–2020. Next, the weather conditions in the years of observation were analyzed and compared with multi-year data covering 30 years preceding the study. The research results show that, in eastern Poland, there is a stable population of D. reticulatus with the peak of activity in spring or autumn (up to a maximum of 359 individuals within 30 min of collection) depending on the year of observation. Ticks of this species may also be active in winter months. The activity of D. reticulatus is influenced by a saturation deficit.

scholarly journals Long-term species richness-abundance dynamics in relation to species departures and arrivals in wintering urban bird assemblages

2019 ◽  
Vol 5 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Jukka Suhonen ◽  
Jukka Jokimäki
Keyword(s):  
Species Richness ◽  
Bird Species ◽  
Total Abundance ◽  
Bird Species Richness ◽  
Abundance Dynamics ◽  
Local Species Richness ◽  
Local Species ◽  
The Mean ◽  
Urban Bird ◽  
Number Of Individuals

Abstract Temporal dynamics of local assemblages depend on the species richness and the total abundance of individuals as well as local departure and arrival rates of species. We used urban bird survey data collected from the same 31 study plots and methods during three winters (1991–1992; 1999–2000 and 2009–2010) to analyze the temporal relationship between bird species richness and total number of individuals (abundance). We also evaluated local departures and arrivals of species in each assemblage. In total, 13,812 individuals of 35 species were detected. The temporal variation in bird species richness followed the variation in the total number of individuals. The numbers of local departure and arrival events were similar. Also, the mean number of individuals of the recently arrived species (8.6) was almost the same as the mean number of individuals of the departed species (8.2). Risk of species departure was inversely related to number of individuals. Local species richness increased by one species when the total abundance of individuals increased by around 125 individuals and vice versa. Our results highlight the important role of local population departures and arrivals in determining the local species richness-abundance dynamics in human-dominated landscapes. Local species richness patterns depend on the total number of individuals as well as both the departure-arrival dynamics of individual species as well as the dynamics of all the species together. Our results support the more individuals hypothesis, which suggests that individual-rich assemblages have more species.

scholarly journals Haematological and Haemostatic Changes Associated with Major Depressive Disorder among Nigerians.

2021 ◽  
Vol 5 (2) ◽  
pp. 238-245
Author(s):  
Oloruntoba A. Ekun
Keyword(s):  
Major Depressive Disorder ◽  
Depressive Disorder ◽  
Sodium Citrate ◽  
Red Cell ◽  
Major Depressive ◽  
Red Cell Indices ◽  
Healthy Control ◽  
The Mean ◽  
Number Of Individuals ◽  
Apparently Healthy

Background: A link between major depressive disorder (MDD) and haematological as well as co-agulation disorders has been postulated. This study aims to evaluate haematological and haemostatic changes among Nigerians with major depressive disorder Methods: Two hundred volunteers consisting of an equal number of individuals diagnosed with major depressive disorder (MDD) based on DMS-IV criteria and apparently healthy control participated in this study. The blood sample was collected into tri-sodium citrate K2EDTA bottles respectively and was evaluated for some haemostatic parameters , using ELISA, Clauss, Quick’s One Stage, Proctor and Rapaport’s methods. Results: The mean WBC, hemoglobin and differential lymphocyte were significantly higher among MDD total volunteers (p < 0.001). The red cell indices and platelet count were lower among MDD (p <0.001). Also the prothrombin time (PT), fibrinogen, protein-C and erythrocytes sedimentation rate (ESR) were all raised (p <0.001) among volunteers with MDD. Positive associations existed be-tween MCV and RBC (r: 0.364; p<0.001), PT and APTT (r: 0.319 p <0.001), APTT and fibrinogen (r: 0.239, p = 0.017) as well as PT and fibrinogen (r: 0.275 p = 0.006) at 95% confidence interval. Conclusion: Changes in total leucocytes count, lymphocytes values and haemostatic parameters among volunteers with depression may impacts deleterious effects on the immune response as well as haemostatic homeostasis, while decreased red cell indices may suggest occult nutritional anaemia.

Examining the Implications of Process and Choice for Strategic Decision Making Effectiveness

2013 ◽  
pp. 344-359
Author(s):  
Paul L. Drnevich ◽  
Thomas H. Brush ◽  
Alok Chaturvedi
Keyword(s):  
Decision Making ◽  
Academic Research ◽  
Decision Processes ◽  
Strategic Decision ◽  
Strategic Decision Making ◽  
Political Decision ◽  
Agent Based ◽  
Response Choice ◽  
Decision Making Processes ◽  
Using Data

Most strategic decision-making (SDM) approaches advocate the importance of decision-making processes and response choices for obtaining effective outcomes. Modern decision-making support system (DMSS) technology is often also needed for complex SDM, with recent research calling for more integrative DMSS approaches. However, scholars tend to take disintegrated approaches and disagree on whether rational or political decision-making processes result in more effective decision outcomes. In this study, the authors examine these issues by first exploring some of the competing theoretical arguments for the process-choice-effectiveness relationship, and then test these relationships empirically using data from a crisis response training exercise using an intelligent agent-based DMSS. In contrast to prior research, findings indicate that rational decision processes are not effective in crisis contexts, and that political decision processes may negatively influence both response choice and decision effectiveness. These results offer empirical evidence to confirm prior unsupported arguments that response choice is an important mediating factor between the decision-making process and its effectiveness. The authors conclude with a discussion of the implications of these findings and the application of agent-based simulation DMSS technologies for academic research and practice.

On the parity of individuals in birth and death processes

1982 ◽  
Vol 14 (03) ◽  
pp. 484-501
Author(s):  
S. K. Srinivasan ◽  
C. R. Ranganathan
Keyword(s):  
General Model ◽  
Death Process ◽  
Birth And Death Process ◽  
Birth Rates ◽  
Birth And Death Processes ◽  
Age Dependent ◽  
The Mean ◽  
Number Of Individuals ◽  
Number Of Births

This paper deals with the parity of individuals in an age-dependent birth and death process. A more general model with parity and age-dependent birth rates is also considered. The mean number of individuals with parity 0, 1, 2, ·· ·is obtained for the two models. The first moments of the total number of births in the population up to time t and the sum of the parities of the individuals existing at time t are obtained. A brief discussion on the parity of individuals in a population including ‘twins' is also given.

Sign in / Sign up

Export Citation Format

Share Document