Homeostatic properties

Soil quality and health play an important role in sustainable agriculture Soil quality assessment provides a basic means to evaluate the sustainability of agricultural and land management systems (Doran and Parkin 1994). Soils that are healthy have homeostatic properties, within broadly set limits (Coleman et al. 1998). The application of compost can results soil quality and health because of the organic matter content and humus-producing properties. 

More generally, our studies offer an example of the value of direct microcalorimetry in studying homeostatic properties of ecosystems. Here, heat dissipation with respect to seasons is an adequate parameter of the ability of the system to return, after transitory oscillations, to a new steady state (a parameter of ecological "resilience"). 

At the same time, one should be aware that the advocates of Gaia posed the problem of the homeostatic properties of the biosphere more precisely than Vernadsky himself based on data collected in the 50 years after Vernadsky wrote down his conclusions. Vernadsky was in no position to make a numerical model of the biosphere comparable with the daisy world modeP and other models of Gaia (Schellnhuber, Wenzel, 1998). In the Vernadskian tradition mathematical modelling of the biosphere was pioneered by Moiseev with colleagues (e.g., Moiseev et aL, 1985). 

Lovelock defines Earth as a living organism, first of all, because of its homeostatic properties. But he draws also some other analogies to show how close the concept of Gaia is linked with the concept of life. Perhaps the most illustrative is his morphological redwood tree - argument. The tree undoubtedly is alive, yet 99 percent is dead" (Lovelock, 1989b, p, 27). Dead wood of a tree can be compared with the apparently inanimate rocks of the Earth. 

Fujita Y, Murakami A, Aizawa K, and Ohki K. Short-term and long-term adaptation of the photosynthetic apparatus homeostatic properties of thylakoids. Advances in Photosynthesis. The Molecular Biology of... 

Recently, Bernard et al. [499] studied oscillations in cyclical neutropenia, a rare disorder characterized by oscillatory production of blood cells. As above, they developed a physiologically realistic model including a second homeostatic control on the production of the committed stem cells that undergo apoptosis at their proliferative phase. By using the same approach, they found a local supercritical Hopf bifurcation and a saddle-node bifurcation of limit cycles as critical parameters (i.e., the amplification parameter) are varied. Numerical simulations are consistent with experimental data and they indicate that regulated apoptosis may be a powerful control mechanism for the production of blood cells. The loss of control over apoptosis can have significant negative effects on the dynamic properties of hemopoiesis. 

Shared receptors are defined as able to bind more than one CK this concept is only valid inside each CK family. For example CCL20, alternatively named liver and activation-regulated CK (LARC), macrophage inflammatory protein-da (MIP-3a) or Exodus-1, is the only CK known to interact with CC CK receptor 6 (CCR6), a property shared with the antimicrobial (i-defensins. The ligand-receptor pair CCL20-CCR6 is responsible for the chemoattraction of immature dendritic cells, effector/memory T cells, and B cells and plays a role at skin and mucosal surfaces under homeostatic and... 

Table 7 Properties of human homeostatic and developmental CC chemokine subfamily ...

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