Several studies have shown that along large-scale regional gradients, community-level compensatory ability selleck chemicals is positively correlated with ANPP and soil resource availability. However, community-level responses to grazing are also expected to be affected by local-scale heterogeneity in ANPP, particularly under low primary productivity typical to arid environments. Here, we studied the effect of local-scale variations in ANPP on the compensatory growth of an annual community in a semi-arid region. For two consecutive years, ANPP was evaluated following shoot damage in sites with different primary productivity. The results demonstrated that annual ANPP varied significantly among sites

and among plots within sites: however, compensatory ability was negatively correlated with annual ANPP, with overcompensation in the least productive patches

and under-compensation in the most productive CA3 purchase patches. This pattern contradicts the positive correlation between ANPP and compensatory ability commonly found along large-scale productivity ecoclines, suggesting that the effects of ANPP on compensatory ability might be scale-dependent. (C) 2010 Elsevier Ltd. All rights reserved.”
“A self-consistent analytical model for a time-independent collisional capacitively coupled plasma (CCP) sheath driven by a triple frequency (TF) RF current source is proposed. Sheath parameters are calculated using this model for some standard plasma parameters and are compared with those of a single frequency (SF) and a dual frequency (DF) capacitively coupled collisional sheath. This model estimates higher values of sheath width and potential with more oscillating behavior compared with SF and DF sheaths. By proper choice of source frequencies or phase differences in the source currents, it is possible to adjust the ion energy hitting the electrode. Use of TF source is found to facilitate better control upon sheath parameters for collisional CCP.”
“Using a three-dimensional electromechanical model of the canine ventricles with dyssynchronous heart failure, we investigated

the relationship between severity of valve regurgitation and ventricular mechanical responses. The results demonstrated that end-systolic tension in the septum and left ventricular free wall was significantly lower under the condition of mitral regurgitation (MR) than learn more under aortic regurgitation (AR). Stroke work in AR was higher than that in MR. On the other hand, the difference in stroke volume between the two conditions was not significant, indicating that AR may cause worse pumping efficiency than MR in terms of consumed energy and performed work.”
“The glycosaminoglycan heparan sulfate (HS), is expressed on the surface of virtually all mammalian cells and is implicated in many crucial biological activities. The activities of HS and its close structural analogue heparin are mediated through interactions with proteins.