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replaced by “invitro” and “invivo” respectively. To understand this dataset's temporal dynamics, bursts, i.e., sudden increases in the frequency of words in titles, new ISI keywords, author keywords and MeSH terms were identified. The top 50
ambiente . Kleba Lisboa , L. , Lemes Da Silva , A.L. , Siegloch , A.E. , Gonçalves , J.F. and Mello Petrucio , M. 2015 . Temporal dynamics of allochthonous coarse
In 2010 on the green roof of the Institute of Biology in Bucharest at a height of 15 meters above ground level 607 Thysanoptera specimens were collected. Altogether 15 species were found to occur mostly in the flowers of a variety of plants in the herbaceous layer, but also some were shaken from small shrubs and trees (Rosa canina and Populus sp.). The temporal dynamics of the thrips populations in this spontaneous vegetation show a peak in the beginning of June, with a slightly descending curve to autumn. Haplothrips leucanthemi, with a consistently high numerical abundance throughout the study, is considered to be a sensitive bio-indicator of the colonisation and naturalisation of this semi-isolated urban biotope.
The bryophyte vegetation of three acidophilous forest communities of radiolarian bedrock was investigated in the Bükk Mts in Hungary. The frequency and the spatial pattern of 7 dominant species were studied in permanent quadrate blocks for three years using Four-Term Local Quadrate Variance (4TLQV) spatial pattern analysis. The size of quadrate blocks were 3,600 cm2 consisted of 20 × 20 cell network and the used data type were the weighted shoot density of the occurring species. The maps and variograms of the occurred terricolous bryophyte species were calculated with a program package called PASSAGE (Pattern Analysis, Spatial Statistics and Geographic Exegesis). The examined bryophyte species were: Ceratodon purpureus, Dicranum scoparium, Hypnum cupressiforme, Leucobryum juniperoideum, Polytrichum formosum, P. piliferum. Using other type of temporal observation methods the results of the analysis is useful for characterising the spatial pattern and temporal dynamics of the examined populations of these bryophyte species within a habitat type.
Evergreens, sensations and the rest
A quantitative analysis of dynamics of news articles on domestic politics
This study investigated the temporal dynamics of articles in connection with ‘lies’ which appeared in Hungarian dailies Népszabadság and Magyar Nemzet during a several year long time period. We targeted to reveal how the press reacted to Hungarian Prime Minister Ferenc Gyurcsány speech, when he said that they had lied throughout his term in office. We present a typology of media dynamics based on our previous results of investigating the same dailies and certain analytical procedures, which arise from the literature about of diffusion of innovations. Having reviewed the possible typology of media dynamics we return to the dynamic analysis of the topic of ‘lying’ or ‘lies’. One of the main results was, that from an “evergreen” ‘lying’ turned into a “sensation-based” topic in the fall of 2006, and the prime minister’s leaked speech was this sensation.
The metacommunity perspective has substantially advanced our understanding of how local (within community) and dispersal (between community) processes influence the assembly of communities. The increased recognition of dispersal processes makes it necessary to re-evaluate former views on community organization in different ecological systems and for specific organisms. Stream systems have long been considered from a linear perspective, in which local community organization was examined along the longitudinal profile, from source to mouth. However, the hierarchically branching (i.e. dendritic) structure of stream networks also significantly affects both local and regional scale community organization, which has just only recently been fully recognized by ecologists. In this review, I examine how the shift from a strictly linear to a dendritic network perspective influenced the thinking about the organization of fish metacommunities in stream networks. I argue that while longitudinal patterns in the structure of fish communities are relatively well known, knowledge is still limited about how the structure of the stream network ultimately affects the spatial and temporal dynamics of metacommunities. I suggest that scaling metapopulation models up to the metacommunity level can be useful to further our understanding of the spatial structure of metacommunities. However, this requires the delineation of local communities and the quantification of the contribution of dispersal to local community dynamics. Exploring patterns in diversity, spatial distribution and temporal dynamics of metacommunities is not easily feasible in continuous stream habitats, where some parts of the habitat network are exceptionally hard to sample representatively. Combination of detailed field studies with modelling of dispersal is necessary for a better understanding of metacommunity dynamics in stream networks. Since most metacommunity level processes are likely to happen at the stream network level, further research on the effects of stream network structure is needed. Overall, separation of the effect of dispersal processes from local scale community dynamics may yield a more mechanistic understanding of the assembly of fish communities in stream networks, which may also enhance the effectiveness of restoration efforts.
Jelen vizsgálat célja a flow- és antiflow-állapotok spektrális jellemzőinek feltárása. A vizsgálatban 20 férfi vizsgálati személy vett részt. Ütközéselkerülést szimuláló számítógépes feladathelyzetekben mértük spektrális EEG aktivitásukat. A flow, unalom és szorongáshelyzetek elkülönítését a feladatként szolgáló játék egyénre szabott paraméterezésével (sebesség) biztosítottuk. Előzetesen felmértük a vizsgálati személyek számítógépes feladathelyzetre vonatkozó készségeit objektív (teljesítményen alapuló) és szubjektív (önbeszámolón alapuló) adatok meghatározásával. A személyenként, helyzetenként vizsgált spektrális mutatókat összevetve azt találtuk, hogy a flow-helyzet a szorongásnál alacsonyabb, míg az unalomnál nagyobb agyi aktivitással jártak együtt a delta, théta-, béta- és gamma-spektrumokon. A rögzített jelek idői lefutása továbbá azt mutatta, hogy a játék első szakaszában a flow- és a szorongáshelyzetekben növekvő spektrális aktivitás jellemző. A játék második szakaszában ez a dinamika megváltozik: Amíg a flow-helyzetben a spektrális mutatók csökkenése (béta és gamma) jelentkezik, addig szorongás esetében a csökkenés nem vagy kevésbé jellemző, unalomhelyzetben viszont enyhe növekedés tapasztalható. Eredményeink alátámasztják a hipofrontalitás elméletét a flow-val kapcsolatban, és rámutatnak arra, hogy a flow-t idői dinamikájában érdemes vizsgálni. Adataink azt is jelzik, hogy a vizsgálati személyek a flow-állapotban nem hatékonyságra, hanem tapasztalat- és információmaximalizálásra törekszenek.
Trueperella (T.) pyogenes is an opportunistic pathogen that causes suppurative diseases in domestic animals. In this work, the properties, pathogenesis and phenotypic diversity of T. pyogenes isolates from bovine mastitis were studied. Both pyolysin (plo) and collagen-binding protein (cbp) virulence factor genes were detected by PCR in all T. pyogenes isolates (n = 50). Using the tissue culture plate method, 90% of T. pyogenes isolates were able to form biofilms. The minimum inhibitory concentrations (MICs) of 13 antimicrobials against T. pyogenes isolates were determined. High susceptibility was observed to rifampin (96%), ampicillin (94%), ciprofloxacin (94%), and penicillin (92%), while low susceptibility was found to trimethoprim-sulphamethoxazole (10%) and bacitracin (2%). The intracellular assay revealed that T. pyogenes isolates had different cytopathogenic effects on cells. The high percentage (28.6%) of T. pyogenes isolates suggests that this bacterium is an important contributor to mastitis. Moreover, the high occurrence of multidrug resistance, biofilm production, intracellular survival, and the temporal dynamics of T. pyogenes interactions are key factors for a better understanding of how immunity acts on infections with these bacteria and how they evade immune surveillance, thus highlighting the need for the prudent use of antimicrobial agents in veterinary medicine.
This paper aims to show the relevance of past ecological records, at centennial to millennial timescales, for community ecological principles and theory, mainly in relation to temporal dynamics and the origin of present-day community patterns. The underlying assumption is that ecological time is a continuum and the ecological understanding of the present biosphere needs inputs from multilevel timescales. In particular, the so-called Q-time, embracing the Quaternary (the last 2.6 million years), is proposed as a key time period to understand present-day patterns and the underlying causal processes, as for example the latitudinal diversity gradient, the relationship between species richness and stability, the equilibrium/non-equilibrium conditions between communities and the environment, the main trends and clues on the origin of present-day species and the communities they form, the community succession under changing environmental conditions, or the nature (individual vs collective) of such biotic responses, among others. In this temporal context, neoecological studies and modeling, based on short-term evidence and calibration/validation data sets, are viewed as an important source for hypotheses to be tested with long-term ecological (i.e., palaeoecological) and molecular phylogenetic studies. The considerations around these topics provide valuable insights to address the potential future state of modern communities under the predicted global change, which would be useful to propose suitable conservation strategies. It is hoped that this paper will promote constructive discussions leading to a more close collaboration between neoecologists and palaeoecologists, in the way towards the natural convergence of both into one single, time-independent, discipline as is (or should be) ecology. As this paper has been conceived for both neo- and palaeoecologists, the message is twofold: to neoecologists, care about time; to palaeoecologists, care about ecology.
Previous studies have suggested that the attenuation of Canada lynx (Lynx canadensis) cyclic dynamics with decreasing latitude may be the consequence of a reduced specialization on the lynx’s primary prey, snowshoe hares (Lepus americanus). However, intraguild competitive interactions remain largely unexplored in situations where the temporal dynamics of food resources is pronounced, and lynx populations in the south of their distribution may be negatively affected by interspecific competition with other carnivores. In this paper, we used spectral analysis of fur harvest data collected at the state (US) and province (Canada) level to explore the spatial gradient of cyclic dynamics in lynx. Although some patterns were consistent with the ‘diet specialization’ hypothesis, we found that temporal variance of cycling propensity peaked at mid-latitudes, where transient, non-cyclic periods, coexisted with regular 10-year cycles. In these mid-latitude zones, non-cyclic periods did not coincide with loss of snowshoe hare cycling as demonstrated by historical records, and were not more frequent in recent decades as could be expected under a ‘climatic forcing’ scenario. Instead, we show that non-cyclic periods tended to coincide with periods of high coyote (Canis latrans) abundance and periods when coyotes apparently tracked snowshoe hare abundance as suggested by significant 10-year cycles lagging one or two years behind hare peaks. We used landscape-scale (trapline) fur harvest returns from five provinces in Canada to further probe the importance of interspecific competition in Canada lynx population dynamics. Accounting for coyote distribution and abundance did not bring additional explanatory and predictive power to models based solely on environmental and autecological predictors, suggesting that competition with coyote is not a force driving population abundance and cyclicity among lynx. We discuss the possible factors behind the apparent lack of consistency across spatial scales and recommend that further studies examine species interactions at a smaller (local) scale.
