ON STRUCTURAL AND GENETIC HETEROGENEITY AN INEXHAUSTIBLE UNIVERSUM

2020 ◽  
pp. 110-122
Author(s):  
Valeriy Finogentov
Keyword(s):  
Spatial Heterogeneity ◽  
Genetic Heterogeneity ◽  
Structural Heterogeneity ◽  
Temporal Heterogeneity ◽  
Substrate Heterogeneity

The article discusses the main aspects of inhomogeneity of an inexhaustible (manifold infinite) universe: structural (spatial) heterogeneity and genetic (temporal) heterogeneity. Such aspects of structural heterogeneity as nomological heterogeneity and substrate heterogeneity are also identified and analyzed. Special attention is paid to this component of the genetic heterogeneity, which is captured by the concept of “tempodesinence”. The concept of ontological non-geocentrism” is critically analyzed.

Role of autoregulation in spatial and temporal perfusion heterogeneity of canine myocardium

1978 ◽  
Vol 235 (1) ◽  
pp. H64-H71 ◽  
Author(s):  
F. J. Sestier ◽  
R. R. Mildenberger ◽  
G. A. Klassen
Keyword(s):  
Spatial Heterogeneity ◽  
Perfusion Pressure ◽  
Diastolic Pressure ◽  
Systolic Pressure ◽  
Ventricular Myocardium ◽  
Small Region ◽  
Left Ventricular ◽  
Left Ventricular Myocardium ◽  
Temporal Heterogeneity ◽  
Ventricular Systolic Pressure

Spatial heterogeneity, the region-to-region variation in flow at an instant, and temporal heterogeneity, the time variation of flow in a small region of myocardium, were investigated with radioactive labeled microspheres in 111 regions of left ventricular myocardium. The error of the method was measured by simultaneously injecting four differently labeled microspheres (15 +/- 5 (SD) micron). The coefficient of variation (CV) was 6.5 +/- 1.0%. Spatial variation with autoregulation intact was 21.7 +/- 1.4% (CV); with autoregulation abolished and low perfusion pressure, it was 34.3 +/- 3.7%; and with normal perfusion pressure, 30.8 +/- 6.4% (differences not significantly). This degree of variation was similar in the entire left ventricle and its layers. Forces which tended to cause vessel closure (low perfusion pressure, ventricular systolic pressure, and ventricular diastolic pressure) tended to increase CV. Temporal heterogeneity as measured by 20-s intervals between microsphere injections was 11.1 +/- 1.0% (CV) with autoregulation, 9.8 +/- 1.3% (P less than 0.05) with autoregulation abolished, and 8.4 +/- 0.8% (P less than 0.05) when perfusion pressure was restored. A periodicity of flow cycles of 30-90 s was suggested by the data. These results suggest that spatial heterogeneity is less influenced by autoregulation than by hydraulic considerations, whereas temporal heterogeneity is a component of autoregulation.

Biodiversity in Heterogeneous and Dynamic Landscapes

2016 ◽  
Author(s):  
Clélia Sirami
Keyword(s):  
Landscape Ecology ◽  
Spatial Heterogeneity ◽  
Environmental Changes ◽  
Landscape Heterogeneity ◽  
Landscape Patterns ◽  
Global Changes ◽  
Time Lags ◽  
Temporal Heterogeneity ◽  
Landscape Models ◽  
Spatial And Temporal Heterogeneity

Although the concept of biodiversity emerged 30 years ago, patterns and processes influencing ecological diversity have been studied for more than a century. Historically, ecological processes tended to be considered as occurring in local habitats that were spatially homogeneous and temporally at equilibrium. Initially considered as a constraint to be avoided in ecological studies, spatial heterogeneity was progressively recognized as critical for biodiversity. This resulted, in the 1970s, in the emergence of a new discipline, landscape ecology, whose major goal is to understand how spatial and temporal heterogeneity influence biodiversity. To achieve this goal, researchers came to realize that a fundamental issue revolves around how they choose to conceptualize and measure heterogeneity. Indeed, observed landscape patterns and their apparent relationship with biodiversity often depend on the scale of observation and the model used to describe the landscape. Due to the strong influence of island biogeography, landscape ecology has focused primarily on spatial heterogeneity. Several landscape models were conceptualized, allowing for the prediction and testing of distinct but complementary effects of landscape heterogeneity on species diversity. We now have ample empirical evidence that patch structure, patch context, and mosaic heterogeneity all influence biodiversity. More recently, the increasing recognition of the role of temporal scale has led to the development of new conceptual frameworks acknowledging that landscapes are not only heterogeneous but also dynamic. The current challenge remains to truly integrate both spatial and temporal heterogeneity in studies on biodiversity. This integration is even more challenging when considering that biodiversity often responds to environmental changes with considerable time lags, and multiple drivers of global changes are interacting, resulting in non-additive and sometimes antagonistic effects. Recent technological advances in remote sensing, the availability of massive amounts of data, and long-term studies represent, however, very promising avenues to improve our understanding of how spatial and temporal heterogeneity influence biodiversity.

scholarly journals Spatial and Temporal Heterogeneity Creates a “Brown Tide” in Root Phenology and Nutrition

ISRN Ecology ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Sean C. P. Coogan ◽  
Scott E. Nielsen ◽  
Gordon B. Stenhouse
Keyword(s):  
Spatial Heterogeneity ◽  
Protein Content ◽  
Crude Protein ◽  
Brown Tide ◽  
Ground Vegetation ◽  
Grizzly Bears ◽  
Temporal Heterogeneity ◽  
Crude Protein Content ◽  
Spatial And Temporal Heterogeneity ◽  
Below Ground

Spatial and temporal heterogeneity in plant phenology and nutrition benefits herbivores by prolonging the period in which they can forage on nutritious plants. Landscape heterogeneity can therefore enhance population performance of herbivores and may be a critically important feature of their habitat. The benefits of resource heterogeneity over space and time should extend not only to large herbivores using above-ground vegetation but also to omnivores that utilize below-ground resources. We used generalized linear models to evaluate whether spatial heterogeneity influenced temporal variation in the crude protein content of alpine sweetvetch (Hedysarum alpinum) roots in west-central Alberta, Canada, thereby potentially offering nutritional benefits to grizzly bears (Ursus arctos). We demonstrated that temporal patterns in the crude protein content of alpine sweetvetch roots were influenced by spatial heterogeneity in annual growing season temperatures and soil moisture and nutrients. Spatial heterogeneity and asynchrony in the protein content of alpine sweetvetch roots likely benefit grizzly bears by prolonging the period they can forage on high quality resources. Therefore, we have presented evidence of what we termed a “brown wave” or “brown tide” in the phenology and nutrition of a below-ground plant resource, which is analogous to the previously described “green wave” in above-ground resources.

Temporal heterogeneity increases with spatial heterogeneity in ecological communities

Ecology ◽  
2018 ◽  
Vol 99 (4) ◽  
pp. 858-865 ◽  
Author(s):  
Scott L. Collins ◽  
Meghan L. Avolio ◽  
Corinna Gries ◽  
Lauren M. Hallett ◽  
Sally E. Koerner ◽  
...  
Keyword(s):  
Spatial Heterogeneity ◽  
Temporal Heterogeneity ◽  
Ecological Communities

Observations on Spatial Heterogeneity of Surface Chlorophyll in one and two Dimensions

1978 ◽  
Vol 58 (2) ◽  
pp. 487-502 ◽  
Author(s):  
J. W. Horwood
Keyword(s):  
The Netherlands ◽  
Spatial Heterogeneity ◽  
Large Scale ◽  
Two Dimensions ◽  
Temporal Heterogeneity ◽  
English Channel ◽  
Spatial And Temporal Heterogeneity ◽  
Careful Measurement ◽  
Present Understanding ◽  
Northeast Coast

I trust that I will not be criticized for saying that, in general, the argument between Hensen and Haeckel has been resolved. Hensen (1887, 1895) believed that true spatial and temporal heterogeneity of the plankton could be resolved by careful measurement and analyses of variance. Haeckel (1893) thought these analyses might give more information than the data possessed. Our present understanding of spatial heterogeneity, and its analysis, does not lead us to disagree with either. Investigations carried out by a number of marine ecologists have shown large-scale spatial variations in phytoplankton. Amongst many others, this feature can be seen in studies off the northeast coast of England (Cushing, 1955), in the English Channel and Celtic Sea (Cushing, 1957; Pingree et al. 1976), off Scotland (Adams, Baird & Dunn, 1975,1976) and off the coast of the Netherlands (Gieskes & Kraay, 1975). Nevertheless the statistics of sampling heterogeneous distributions is far from simple, estimates of density for instance can be greatly influenced by the sample size (e.g. Greig-Smith, 1964; Cassie, 1963). Bainbridge (1957) summarized his review by saying that patches occurred on all scales from a few feet to as much as 30 or 40 miles by 120 or 180 miles. Our present understanding of the nature of turbulence in the sea would reduce his few feet to centimetres.

scholarly journals Spatial and Temporal Heterogeneity of Tumor-Infiltrating Lymphocytes in Advanced Urothelial Cancer

2022 ◽  
Vol 12 ◽  
Author(s):  
Sandra van Wilpe ◽  
Mark A. J. Gorris ◽  
Lieke L. van der Woude ◽  
Shabaz Sultan ◽  
Rutger H. T. Koornstra ◽  
...  
Keyword(s):  
Spatial Heterogeneity ◽  
Urothelial Cancer ◽  
Immune Cell ◽  
Checkpoint Inhibitors ◽  
Tumor Infiltrating Lymphocytes ◽  
Temporal Heterogeneity ◽  
Platinum Based Chemotherapy ◽  
Spatial And Temporal Heterogeneity ◽  
Cell Densities ◽  
Infiltrating Lymphocytes

Checkpoint inhibitors targeting PD-(L)1 induce objective responses in 20% of patients with metastatic urothelial cancer (UC). CD8+ T cell infiltration has been proposed as a putative biomarker for response to checkpoint inhibitors. Nevertheless, data on spatial and temporal heterogeneity of tumor-infiltrating lymphocytes in advanced UC are lacking. The major aims of this study were to explore spatial heterogeneity for lymphocyte infiltration and to investigate how the immune landscape changes during the disease course. We performed multiplex immunohistochemistry to assess the density of intratumoral and stromal CD3+, CD8+, FoxP3+ and CD20+ immune cells in longitudinally collected samples of 49 UC patients. Within these samples, spatial heterogeneity for lymphocyte infiltration was observed. Regions the size of a 0.6 tissue microarray core (0.28 mm2) provided a representative sample in 60.6 to 71.6% of cases, depending on the cell type of interest. Regions of 3.30 mm2, the median tumor surface area in our biopsies, were representative in 58.8 to 73.8% of cases. Immune cell densities did not significantly differ between untreated primary tumors and metachronous distant metastases. Interestingly, CD3+, CD8+ and FoxP3+ T cell densities decreased during chemotherapy in two small cohorts of patients treated with neoadjuvant or palliative platinum-based chemotherapy. In conclusion, spatial heterogeneity in advanced UC challenges the use of immune cell infiltration in biopsies as biomarker for response prediction. Our data also suggests a decrease in tumor-infiltrating T cells during platinum-based chemotherapy.

scholarly journals Spatio-Temporal Heterogeneity of Climate Warming in the Chinese Tianshan Mountainous Region

Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 199
Author(s):  
Xuemei Li ◽  
Bo Zhang ◽  
Rui Ren ◽  
Lanhai Li ◽  
Slobodan P. Simonovic
Keyword(s):  
Spatial Heterogeneity ◽  
Air Temperature ◽  
Climate Warming ◽  
Temporal Heterogeneity ◽  
Mountainous Region ◽  
Local Cooling ◽  
Chinese Tianshan ◽  
Temporal And Spatial ◽  
Spatio Temporal ◽  
Temporal And Spatial Heterogeneity

The Chinese Tianshan mountainous region (CTMR) is a typical alpine region with high topographic heterogeneity, characterized by a large altitude span, complex topography, and diverse landscapes. A significant increase in air temperature had occurred in the CTMR during the last five decades. However, the detailed, comprehensive, and systematical characteristics of climate warming, such as its temporal and spatial heterogeneity, remain unclear. In this study, the temporal and spatial heterogeneity of climate warming across the CTMR had been comprehensively analyzed based on the 10-day air temperature data gathered during 1961–2020 from 26 meteorological stations. The results revealed local cooling in the context of general warming in the CTMR. The amplitude of variation (AV) varied from −0.57 to 3.64 °C, with the average value of 1.19 °C during the last six decades. The lapse rates of the elevation-dependent warming that existed annually, and in spring, summer, and autumn are −0.5 °C/100 m, −0.5 °C/100 m, −0.7 °C/100 m, and −0.4 °C/100 m, respectively. The warming in the CTMR is characteristic of high temporal heterogeneity, as represented by the amplified warming at 10-d scale for more than half a year, and the values of AV were higher than 1.09 °C of the global warming during 2011–2020 (GWV2011–2020). Meanwhile, the amplitudes of warming differed greatly on a seasonal scale, with the rates in spring, autumn, and winter higher than that in summer. The large spatial heterogeneity of climate warming also occurred across the CTMR. The warming pole existed in the warm part, the Turpan-Hami basin (below 1000 m asl) where the air temperature itself was high. That is, the warm places were warmer across the CTMR. The cooling pole was also found in the Kuqa region (about 1000 m asl). This study could greatly improve the understanding of the spatio-temporal dynamics, patterns, and regional heterogeneity of climate warming across the CTMR and even northwest China.

Burning history, time of burning, and year effects on plant community structure and heterogeneity in Fescue Prairie

Botany ◽  
2010 ◽  
Vol 88 (1) ◽  
pp. 1-12 ◽  
Author(s):  
D. V. Gross ◽  
J. T. Romo
Keyword(s):  
Community Structure ◽  
Species Composition ◽  
Spatial Heterogeneity ◽  
Plant Community ◽  
Canopy Cover ◽  
Plant Functional Groups ◽  
Plant Community Structure ◽  
Temporal Heterogeneity ◽  
Spatial And Temporal Heterogeneity ◽  
Festuca Hallii

Structure, as well as spatial and temporal heterogeneity in plant species composition were studied in a Festuca hallii (Vasey) Piper – dominated Prairie in Canada for 6 years following burning before, during, or after the growing season on sites burned 1× or 3×. Structure, spatial heterogeneity, and temporal heterogeneity were never (P > 0.05) influenced by the time of burning. Diversity and richness of graminoids, perennial forbs, and shrubs fluctuated among years after burning, but were unaffected by burning history. Excepting shrubs, canopy cover of plant functional groups positively correlated with precipitation. After a single burn, spatial heterogeneity in species composition increased with years after burning, indicating plant communities were becoming patchier, whereas those burned 3× did not change predictably through time. Spatial heterogeneity in species composition between consecutive years was positively correlated, but temporal heterogeneity in species composition did not correlate with spatial heterogeneity. Burning history and precipitation appear important in controlling the plant community structure and spatial heterogeneity in species composition in Fescue Prairie.

Cell Wall Ultrastructure in Three Strains of a Cariogenic Streptococcus

1971 ◽  
Vol 29 ◽  
pp. 338-339
Author(s):  
M. J. Kramer ◽  
Alan L. Coykendall
Keyword(s):  
Cell Wall ◽  
Dental Caries ◽  
Streptococcus Mutans ◽  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Genetic Heterogeneity ◽  
Morphological Characteristics ◽  
Electron Microscopic ◽  
Dna Reassociation ◽  
Wall Ultrastructure

During the almost 50 years since Streptococcus mutans was first suggested as a factor in the etiology of dental caries, a multitude of studies have confirmed the cariogenic potential of this organism. Streptococci have been isolated from human and animal caries on numerous occasions and, with few exceptions, they are not typable by the Lancefield technique but are relatively homogeneous in their biochemical reactions. An analysis of the guanine-cytosine (G-C) composition of the DNA from strains K-1-R, NCTC 10449, and FA-1 by one of us (ALC) revealed significant differences and DNA-DNA reassociation experiments indicated that genetic heterogeneity existed among the three strains. The present electron microscopic study had as its objective the elucidation of any distinguishing morphological characteristics which might further characterize the respective strains.

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