scholarly journals Modelling the mobility of living organisms in heterogeneous landscapes: does memory improve foraging success?

2010 ◽  
Vol 368 (1933) ◽  
pp. 5645-5659 ◽  
Author(s):  
Denis Boyer ◽  
Peter D. Walsh
Keyword(s):  
Foraging Efficiency ◽  
Mobility Patterns ◽  
Heterogeneous Landscapes ◽  
Technological Advances ◽  
Spatio Temporal ◽  
Living Organisms ◽  
Large Animals ◽  
Micro Organisms ◽  
Random Nature ◽  
Basic Movement

Thanks to recent technological advances, it is now possible to track with an unprecedented precision and for long periods of time the movement patterns of many living organisms in their habitat. The increasing amount of data available on single trajectories offers the possibility of understanding how animals move and of testing basic movement models. Random walks have long represented the main description for micro-organisms and have also been useful to understand the foraging behaviour of large animals. Nevertheless, most vertebrates, in particular humans and other primates, rely on sophisticated cognitive tools such as spatial maps, episodic memory and travel cost discounting. These properties call for other modelling approaches of mobility patterns. We propose a foraging framework where a learning mobile agent uses a combination of memory-based and random steps. We investigate how advantageous it is to use memory for exploiting resources in heterogeneous and changing environments. An adequate balance of determinism and random exploration is found to maximize the foraging efficiency and to generate trajectories with an intricate spatio-temporal order, where travel routes emerge without multi-step planning. Based on this approach, we propose some tools for analysing the non-random nature of mobility patterns in general.

Water Pollution and Its Impact on Environment of Society

2016 ◽  
Vol 3 (5) ◽  
Author(s):  
N. Thyagaraju
Keyword(s):  
Water Pollution ◽  
Pollution Prevention ◽  
Human Beings ◽  
Individual Level ◽  
The Public ◽  
The Government ◽  
Living Organisms ◽  
Set Up ◽  
Biological Entities ◽  
Micro Organisms

The present seminar paper mainly highlight  the concept of  water pollution, causes of water pollution,  Its Effects, Elements of  pollutants, Methods  used to prevent the water pollution in environment  and the mandatory initiatives taken by the concerned authorities for prevention of  water pollution. Water   is essential for survival of all living organisms on the earth. Thus for human beings and plants to survive on land, water should be easily accessible. The term “Pollution” is generally refers to addition of any foreign body either living or non – living or deletion of anything that naturally exists. The basic Sources of Water pollution causes due to Culmination into lakes, rivers, ponds, seas, oceans etc. Domestic drainage and sanitary waste, Industrial drainage and sewage, Industrial waste from factories, Dumping of domestic garbage, Immersion of Idols made of plaster of Paris, Excess use of Insecticides , pesticides, fungicides, Chemical fertilizers, Soil erosion during heavy rains and floods, Natural disasters, tsunami etc. General pollutants  which are also caused for water pollution  which include Organic, Inorganic, and Biological entities, Insecticides, Pesticides, Disinfectants ,Detergents, Industrial solvents, Acids, Ammonia fertilizers, heavy metals, Harmful bacteria, Virus, Micro –Organisms and worms, Toxic chemicals. Agricultural lands become infertile and thereby production also drops, Spread of epidemic diseases like Cholera, Dysentery, Typhoid, Diarrhea, Hepatitis, Jaundice etc. The  basic responsibility of the Government, NGOs, National Pioneer scientific Research Institutions may conduct  research oriented programs on control of water pollution by create  awareness among the public through mass media and Environmental Education on recycling units,  and  water treatment plants must be established both at domestic levels and Industry levels, Every citizen must feel responsible to control water pollution. There have been many water pollution prevention acts that have been set up by the governments of the world. But these are not enough for permanent water pollution solutions. Each of us needs to take up the responsibility and do something at an everyday at individual level. Otherwise we can’t survive in a society forever in a future. 

Diversity of organisms

2018 ◽  
Author(s):  
Philip James
Keyword(s):  
Life Cycle ◽  
Urban Areas ◽  
Native Species ◽  
New Technologies ◽  
Urban Environments ◽  
Green Spaces ◽  
The Common ◽  
Living Organisms ◽  
Micro Organisms ◽  
Diversity Of Life

The focus of this chapter is an examination of the diversity of living organisms found within urban environments, both inside and outside buildings. The discussion commences with prions and viruses before moving on to consider micro-organisms, plants, and animals. Prions and viruses cause disease in plants and animals, including humans. Micro-organisms are ubiquitous and are found in great numbers throughout urban environments. New technologies are providing new insights into their diversity. Plants may be found inside buildings as well as in gardens and other green spaces. The final sections of the chapter offer a discussion of the diversity of animals that live in urban areas for part or all of their life cycle. Examples of the diversity of life in urban environments are presented throughout, including native and non-native species, those that are benign and deadly, and the common and the rare.

scholarly journals A robust machine learning approach to SDG data segmentation

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Kassim S. Mwitondi ◽  
Isaac Munyakazi ◽  
Barnabas N. Gatsheni
Keyword(s):  
Temporal Variations ◽  
Data Repository ◽  
The Sustainable Development ◽  
Complex Interactions ◽  
Data Segmentation ◽  
Technological Advances ◽  
Machine Learning Approach ◽  
Development Goals ◽  
Data Source ◽  
Spatio Temporal

Abstract In the light of the recent technological advances in computing and data explosion, the complex interactions of the Sustainable Development Goals (SDG) present both a challenge and an opportunity to researchers and decision makers across fields and sectors. The deep and wide socio-economic, cultural and technological variations across the globe entail a unified understanding of the SDG project. The complexity of SDGs interactions and the dynamics through their indicators align naturally to technical and application specifics that require interdisciplinary solutions. We present a consilient approach to expounding triggers of SDG indicators. Illustrated through data segmentation, it is designed to unify our understanding of the complex overlap of the SDGs by utilising data from different sources. The paper treats each SDG as a Big Data source node, with the potential to contribute towards a unified understanding of applications across the SDG spectrum. Data for five SDGs was extracted from the United Nations SDG indicators data repository and used to model spatio-temporal variations in search of robust and consilient scientific solutions. Based on a number of pre-determined assumptions on socio-economic and geo-political variations, the data is subjected to sequential analyses, exploring distributional behaviour, component extraction and clustering. All three methods exhibit pronounced variations across samples, with initial distributional and data segmentation patterns isolating South Africa from the remaining five countries. Data randomness is dealt with via a specially developed algorithm for sampling, measuring and assessing, based on repeated samples of different sizes. Results exhibit consistent variations across samples, based on socio-economic, cultural and geo-political variations entailing a unified understanding, across disciplines and sectors. The findings highlight novel paths towards attaining informative patterns for a unified understanding of the triggers of SDG indicators and open new paths to interdisciplinary research.

scholarly journals Polyacrylamide Bead Sensors for in vivo Quantification of Cell-Scale Stress in Zebrafish Development

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
N. Träber ◽  
K. Uhlmann ◽  
S. Girardo ◽  
G. Kesavan ◽  
K. Wagner ◽  
...  
Keyword(s):  
Computational Analysis ◽  
Tissue Level ◽  
Quantitative Investigation ◽  
Pulsatile Pressure ◽  
Spatio Temporal ◽  
Stress Sensing ◽  
Living Organisms ◽  
Insight Into

AbstractMechanical stress exerted and experienced by cells during tissue morphogenesis and organ formation plays an important role in embryonic development. While techniques to quantify mechanical stresses in vitro are available, few methods exist for studying stresses in living organisms. Here, we describe and characterize cell-like polyacrylamide (PAAm) bead sensors with well-defined elastic properties and size for in vivo quantification of cell-scale stresses. The beads were injected into developing zebrafish embryos and their deformations were computationally analyzed to delineate spatio-temporal local acting stresses. With this computational analysis-based cell-scale stress sensing (COMPAX) we are able to detect pulsatile pressure propagation in the developing neural rod potentially originating from polarized midline cell divisions and continuous tissue flow. COMPAX is expected to provide novel spatio-temporal insight into developmental processes at the local tissue level and to facilitate quantitative investigation and a better understanding of morphogenetic processes.

scholarly journals Uncovering Spatio-temporal Travel Patterns Using a Tensor-based Model from Metro Smart Card Data in Shenzhen, China

2020 ◽  
Vol 12 (4) ◽  
pp. 1475 ◽  
Author(s):  
Jinjun Tang ◽  
Xiaolu Wang ◽  
Fang Zong ◽  
Zheng Hu
Keyword(s):  
Temporal Distribution ◽  
Spatial Dimension ◽  
Urban Traffic ◽  
Travel Patterns ◽  
Mobility Patterns ◽  
Shenzhen City ◽  
Temporal And Spatial ◽  
Spatio Temporal ◽  
Temporal Dimensions ◽  
Metro Network

Individual mobility patterns are an important factor in urban traffic planning and traffic flow forecasting. How to understand the spatio-temporal distribution of passengers deeply and accurately, so as to provide theoretical support for the planning and operation of the metro network, is an urgent issue of wide concern. In this paper, we applied NCP decomposition to uncover the characteristics of travel patterns from temporal and spatial dimensions in the metro network of Shenzhen City. Utilizing matrix factorization and correlation analysis, we extracted several stable components from the collective mobility and find that the departure and arrival mobility patterns have different characteristics in both the temporal and spatial dimension. According to the point of interest (POI) data in the Shenzhen City, the function attributes of the station are identified and then we found that the spatial distribution characteristics of different patterns are different. We explored the distribution of travel time classified according to the spatio-temporal characteristics of stable patterns. The proposed method can decompose stable travel patterns from the collective mobility and the results in this study can help us to better understand different mobility patterns in both spatial and temporal dimensions.

scholarly journals A multi-scale eco-evolutionary model of cooperation reveals how microbial adaptation influences soil decomposition

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Elsa Abs ◽  
Hélène Leman ◽  
Régis Ferrière
Keyword(s):  
Temporal Dynamics ◽  
Global Environmental Change ◽  
Evolutionary Model ◽  
Terrestrial Ecosystems ◽  
Microbial Decomposition ◽  
Multi Scale ◽  
Spatio Temporal ◽  
The Stability ◽  
Micro Organisms ◽  
Som Decomposition

AbstractThe decomposition of soil organic matter (SOM) is a critical process in global terrestrial ecosystems. SOM decomposition is driven by micro-organisms that cooperate by secreting costly extracellular (exo-)enzymes. This raises a fundamental puzzle: the stability of microbial decomposition in spite of its evolutionary vulnerability to “cheaters”—mutant strains that reap the benefits of cooperation while paying a lower cost. Resolving this puzzle requires a multi-scale eco-evolutionary model that captures the spatio-temporal dynamics of molecule-molecule, molecule-cell, and cell-cell interactions. The analysis of such a model reveals local extinctions, microbial dispersal, and limited soil diffusivity as key factors of the evolutionary stability of microbial decomposition. At the scale of whole-ecosystem function, soil diffusivity influences the evolution of exo-enzyme production, which feeds back to the average SOM decomposition rate and stock. Microbial adaptive evolution may thus be an important factor in the response of soil carbon fluxes to global environmental change.

scholarly journals Understanding spatio-temporal mobility patterns for seniors, child/student and adult using smart card data

2014 ◽  
Vol XL-1 ◽  
pp. 167-172 ◽  
Author(s):  
X. Huang ◽  
J. Tan
Keyword(s):  
Urban Areas ◽  
Weighted Graph ◽  
Human Movement ◽  
Travel Behaviour ◽  
Transportation Systems ◽  
Global Network ◽  
Mobility Patterns ◽  
Urban Dynamics ◽  
Spatio Temporal ◽  
Using Data

Commutes in urban areas create interesting travel patterns that are often stored in regional transportation databases. These patterns can vary based on the day of the week, the time of the day, and commuter type. This study proposes methods to detect underlying spatio-temporal variability among three groups of commuters (senior citizens, child/students, and adults) using data mining and spatial analytics. Data from over 36 million individual trip records collected over one week (March 2012) on the Singapore bus and Mass Rapid Transit (MRT) system by the fare collection system were used. Analyses of such data are important for transportation and landuse designers and contribute to a better understanding of urban dynamics. <br><br> Specifically, descriptive statistics, network analysis, and spatial analysis methods are presented. Descriptive variables were proposed such as density and duration to detect temporal features of people. A directed weighted graph G &equiv; (N , L, W) was defined to analyze the global network properties of every pair of the transportation link in the city during an average workday for all three categories. Besides, spatial interpolation and spatial statistic tools were used to transform the discrete network nodes into structured human movement landscape to understand the role of transportation systems in urban areas. The travel behaviour of the three categories follows a certain degree of temporal and spatial universality but also displays unique patterns within their own specialties. Each category is characterized by their different peak hours, commute distances, and specific locations for travel on weekdays.

scholarly journals Preface

1995 ◽  
Vol 347 (1319) ◽  
pp. 3-3
Keyword(s):  
Escherichia Coli ◽  
Saccharomyces Cerevisiae ◽  
Molecular Mechanisms ◽  
Model Systems ◽  
Biochemical Pathways ◽  
Major Threat ◽  
Environmental Agents ◽  
Living Organisms ◽  
New Research ◽  
Micro Organisms

Genomic instability is a major threat to living organisms. To counteract the damaging effects posed by endogenous and environmental agents, such as chemicals or radiation, micro-organisms devote several percent of their genome to encode proteins that function in the repair and recombination of DNA. For many years, a relatively small group of scientists have carefully delineated the molecular mechanisms of these repair processes, using the simplest model systems available, namely Escherichia coli and Saccharomyces cerevisiae . These studies, which until recently had only moderate impact outside of the field, now provide the cornerstone for exciting new research into analogous processes in hum an cells. The reason for this is the revelation that the biochemical pathways for the accurate replication, repair and recombination of DNA have been conserved through evolution.

scholarly journals Does Shoot Apical Meristem Function as the Germline in Safeguarding Against Excess of Mutations?

2021 ◽  
Vol 12 ◽  
Author(s):  
Agata Burian
Keyword(s):  
Cell Fate ◽  
Shoot Apical Meristem ◽  
Apical Meristem ◽  
Cell Lineage ◽  
Temporal Distribution ◽  
Tissue Level ◽  
Protective Mechanisms ◽  
Genetic Continuity ◽  
Spatio Temporal ◽  
Living Organisms

A genetic continuity of living organisms relies on the germline which is a specialized cell lineage producing gametes. Essential in the germline functioning is the protection of genetic information that is subjected to spontaneous mutations. Due to indeterminate growth, late specification of the germline, and unique longevity, plants are expected to accumulate somatic mutations during their lifetime that leads to decrease in individual and population fitness. However, protective mechanisms, similar to those in animals, exist in plant shoot apical meristem (SAM) allowing plants to reduce the accumulation and transmission of mutations. This review describes cellular- and tissue-level mechanisms related to spatio-temporal distribution of cell divisions, organization of stem cell lineages, and cell fate specification to argue that the SAM functions analogous to animal germline.

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