Distribution and activity patterns in an intertidal grazer assemblage: influence of temporal and spatial organization on interspecific associations

ABSTRACT Bacteria growing in biofilms often develop multicellular, three-dimensional structures known as microcolonies. Complex differentiation within biofilms of Pseudomonas aeruginosa occurs, leading to the creation of voids inside microcolonies and to the dispersal of cells from within these voids. However, key developmental processes regulating these events are poorly understood. A normal component of multicellular development is cell death. Here we report that a repeatable pattern of cell death and lysis occurs in biofilms of P. aeruginosa during the normal course of development. Cell death occurred with temporal and spatial organization within biofilms, inside microcolonies, when the biofilms were allowed to develop in continuous-culture flow cells. A subpopulation of viable cells was always observed in these regions. During the onset of biofilm killing and during biofilm development thereafter, a bacteriophage capable of superinfecting and lysing the P. aeruginosa parent strain was detected in the fluid effluent from the biofilm. The bacteriophage implicated in biofilm killing was closely related to the filamentous phage Pf1 and existed as a prophage within the genome of P. aeruginosa. We propose that prophage-mediated cell death is an important mechanism of differentiation inside microcolonies that facilitates dispersal of a subpopulation of surviving cells.

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Temporal and spatial activity of the key-hole limpet Fissurella crassa (Mollusca: Gastropoda) in the eastern Pacific

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531540100412x ◽

2001 ◽

Vol 81 (3) ◽

pp. 485-490 ◽

Cited By ~ 10

Author(s):

Gianluca Serra ◽

Guido Chelazzi ◽

Juan C. Castilla

Keyword(s):

Activity Patterns ◽

Total Duration ◽

Central Place ◽

Quantitative Information ◽

Maximum Distance ◽

Central Place Foraging ◽

Spatial Activity ◽

Average Speed ◽

Spatial Activity Pattern ◽

Temporal And Spatial

An automated photographic technique was used to collect quantitative information on the activity patterns of Fissurella crassa under heavy-exposed sea conditions.The activity of this key-hole limpet was confined to nocturnal low tides. Total length of excursions was significantly greater during spring tides than neap tides, as was the maximum distance reached from the refuge. Total duration of excursions and their average speed did not vary significantly according to the spring/neap cycle. While the direction angle of excursions relative to the refuge was not influenced significantly by the spring/neap cycle, the lowest zone within the intertidal was reached by F. crassa during spring low tides only.Fissurella crassa showed a spatial activity pattern fluctuating intra/inter-individually between a central place foraging and a ranging strategy, with a marked propensity for the former. Looped excursions were characterized by higher speed for the movements away and toward the limpet's refuge, than the movements at maximum distance from the refuge. As the outward and inward branches of looped excursions often overlapped extensively, trail-following is suggested as the main mechanism of orientation used by F. crassa to relocate the refuge.

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Temporal and spatial organization of doctors' computer usage in a UK hospital department

Medical Informatics and the Internet in Medicine ◽

10.1080/14639230500298693 ◽

2005 ◽

Vol 30 (2) ◽

pp. 135-142

Author(s):

H. M. G. Martins ◽

P. Nightingale ◽

M. R. Jones

Keyword(s):

Spatial Organization ◽

Computer Usage ◽

Hospital Department ◽

Temporal And Spatial

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Temporal and spatial organization of gait-related electrocortical potentials

Neuroscience Letters ◽

10.1016/j.neulet.2015.05.036 ◽

2015 ◽

Vol 599 ◽

pp. 75-80 ◽

Cited By ~ 9

Author(s):

Kristel Knaepen ◽

Andreas Mierau ◽

Helio Fernandez Tellez ◽

Dirk Lefeber ◽

Romain Meeusen

Keyword(s):

Spatial Organization ◽

Temporal And Spatial

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Communication Code as Pillar of Successful Communication in Social Cultural Institution (by Example of Theatrical Discourse)

SHS Web of Conferences ◽

10.1051/shsconf/20185001036 ◽

2018 ◽

Vol 50 ◽

pp. 01036

Author(s):

Larissa Vikulova ◽

Evgeniia Serebrennikova ◽

Olga Vostrikova ◽

Liudmila Borbotko

Keyword(s):

Spatial Organization ◽

Verbal Communication ◽

Behavioral Pattern ◽

Cultural Institution ◽

Successful Communication ◽

Communication Processes ◽

The Social ◽

Vector Direction ◽

Temporal And Spatial ◽

Communicative Space

The paper attempts to define constituting features of theatrical discourse which determine functioning of the latter in theatre communicative space. Communication code moderates the addresser-addressee interrelations thus playing a key role in the realization of theatrical discourse as a ritualized, institutional and conventional semiotic unit. The study also aims at introducing a typology of theatrical discourse participants and at defining the addressing vector direction. Communication code is estimated as a moderator of theatrical communication processes and an indicator of communication success / failure. The audience is viewed as a social addressee – an element obligatory for theatrical discourse to be externalized. The audience’s behavioral pattern is largely attributed to the existing communication code: the audience is conscious of their silent role, the verbal communication being somewhat one-way. Conversely, theatrical discourse implies reaction on behalf of the audience. The communication code significantly affects the temporal and spatial framework of theatre communication alongside the actual theatre space existence. The social cultural institution of theatre is targeted at sustaining the society moral values and forming new cognitive and ethical ones. These functions of theatre are also of primary importance. The research results in the drafted principles of the code of verbal communication applied to theatrical discourse, viz. the principle of temporal and spatial organization; the principle of muteness; the principle of prescript observation and the axiological awareness principle.

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Characteristics of Non-Smokers’ Exposure Using Indirect Smoking Indicators and Time Activity Patterns

Sustainability ◽

10.3390/su12219099 ◽

2020 ◽

Vol 12 (21) ◽

pp. 9099

Author(s):

Byung Lyul Woo ◽

Min Kyung Lim ◽

Eun Young Park ◽

Jinhyeon Park ◽

Hyeonsu Ryu ◽

...

Keyword(s):

Exposure Time ◽

Secondhand Smoke ◽

Activity Patterns ◽

Time Activity ◽

Spatial Characteristics ◽

Exposure Biomarkers ◽

Shs Exposure ◽

Temporal And Spatial ◽

Temporal And Spatial Characteristics ◽

Exposure To Secondhand Smoke

Since the global enforcement of smoke-free policies, indoor smoking has decreased significantly, and the characteristics of non-smokers’ exposure to secondhand smoke (SHS) has changed. The purpose of this study was to assess the temporal and spatial characteristics of SHS exposure in non-smokers by combining questionnaires and biomarkers with time activity patterns. To assess SHS exposure, biomarkers such as cotinine and 4-(methylnitrosamino)-1-3-(pyridyl)-1-butanol (NNAL) in urine and nicotine in hair were collected from 100 non-smokers in Seoul. Questionnaires about SHS exposure and time activity patterns were also obtained from the participants. The analysis of biomarker samples indicated that about 10% of participants were exposed to SHS when compared with the criteria from previous studies. However, 97% of the participants reported that they were exposed to SHS at least once weekly. The participants were most exposed to SHS in the outdoor microenvironment, where they spent approximately 1.2 h daily. There was a significant correlation between the participants’ time spent outdoors and self-reported SHS exposure time (r2 = 0.935). In this study, a methodology using time activity patterns to assess temporal and spatial characteristics of SHS exposure was suggested. The results of this study may help develop policies for managing SHS exposure, considering the time activity patterns.

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Colonization of Warsaw by the red fox Vulpes vulpes in the years 1976–2019

Scientific Reports ◽

10.1038/s41598-021-92844-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mateusz Jackowiak ◽

Jakub Gryz ◽

Karolina Jasińska ◽

Michał Brach ◽

Leszek Bolibok ◽

...

Keyword(s):

Vulpes Vulpes ◽

Red Fox ◽

Activity Patterns ◽

Habitat Type ◽

Population Abundance ◽

Temporal And Spatial Patterns ◽

Green Areas ◽

Abundance Trends ◽

Riparian Habitats ◽

Temporal And Spatial

AbstractThe red fox is one of the most adaptable carnivores inhabiting cities. The aim of our study was to describe the process of Warsaw colonization by the red fox. We focused on: (1) the fox distribution in Warsaw on the basis of presence-absence data (2005–2012) over a grid of 1 × 1 km2, (2) the process of settlement in 29 green areas (study periods 1976–1978, 2004–2012, and 2016–2019) in relation to habitat type, and (3) temporal and spatial patterns of the red fox incidents (1998–2015) reported by Warsaw citizens. We found out that: (1) the red fox penetrated the whole city (i.e. its presence was confirmed in all squares of the grid), (2) 21% of the green areas were colonized in 1976–1978 but 93% in 2016–2019. Forests and riparian habitats were occupied more frequently than parks and cemeteries in 1976–1978 with no difference in the further years; (3) the probability of the fox incidents increased over years, was higher in June-October, on working days, and around noon, and with the share of discontinuous urban fabric in the buffers around incident locations. Nevertheless, the incidents only partially reflect population abundance trends and activity patterns of the species, so should be treated cautiously.

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