Plant-plant interactions vary greatly along a flooding gradient in a dam-induced riparian habitat.

Plant-plant interactions under extreme environmental stress are still controversial. The stress gradient hypothesis (SGH) proposes that facilitation prevails under extreme environmental stresses, while an alternative view states that facilitation collapses or even switches back to competition at the extreme end of stress gradients. However, how the relationship between plant-plant interaction and periodic extreme flooding stress varies and its underlying mechanism are still unclear in a dam-regulated riparian ecosystem.

Global Container Port Network Linkages and Topology in 2021.

The maritime transport of containers between ports accounts for the bulk of global trade by weight and value. Transport impedance among ports through transit times and port infrastructures can, however, impact accessibility, trade performance, and the attractiveness of ports. Assessments of the transit routes between ports based on performance and attractiveness criteria can provide a topological liner shipping network that quantifies the performance profile of ports.

Diagnostic Accuracy of Double Contrast-Enhanced Ultrasonography in Clarifying Tumor Depth (T Stage) of Gastric Cancer: Meta-analysis.

This study aimed to quantitatively analyze published data regarding the ability of double contrast-enhanced ultrasonography (DCEUS) to clarify tumor depth (T stage) in primary gastric carcinoma patients. We obtained six studies, including 926 gastric cancer (GC) patients who were diagnosed by DCEUS from the Cochrane Library "Cochrane Central Register of Controlled Trials (CENTRAL)," OVID MEDLINE, EMBASE, PUBMED and EBSCOhost, to 2019. Sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), forest plot analysis and summary receiver operating characteristic (SROC) curve analysis were used to evaluate the diagnostic accuracy of DCEUS.

[Mechanical strain of different waveform and frequency inhibits proliferation of lung adenocarcinoma cell in vitro].

The effects of waveform and frequency on proliferation of human lung adenocarcinoma cell line A549 were studied by FX-4000 strain unit . The results showed that cellular proliferation index (PI) reduced significantly in squarewave group when compared with the control after A549 cells were subjected to collagen I 0-25% elongation at frequency 20 cycles/min, 40 cycles/min and 60 cycles/min for 2h. The PI showed no distinct difference in trianglewave group.

Membrane phospholipid redistribution in cytokinesis: a theoretical model.

In cell mitosis, cytokinesis is a major deformation process, during which the site of the contractile ring is determined by the biochemical stimulus from asters of the mitotic apparatus, actin and myosin assembly is related to the motion of membrane phospholipids, and local distribution and arrangement of the microfilament cytoskeleton are different at different cytokinesis stages. Based on the Zinemanas-Nir model, a new model is proposed in this study to simulate the entire process by coupling the biochemical stimulus with the mechanical actions. There were three assumptions in this model: the movements of phospholipid proteins are driven by gradients of biochemical stimulus on the membrane surface; the local assembly of actin and myosin filament depends on the amount of phospholipid proteins at the same location; and the surface tension includes membrane tensions due to both the passive deformation of the membrane and the active contraction of actin filament, which is determined by microfilament redistribution and rearrangement.

[Stability analysis of micropipette aspiration of cell by liquid drop modeling].

A generally realized phenomenon in the suction experiment of cells is that if the aspiration pressure is larger than a certain threshold, cell flows continuously into the pipette. The point of the threshold aspiration pressure at which the cell can still be held in a stable equilibrium is called the critical point of aspiration. Here we represent a theoretical analysis of the equilibrium behavior and stability of cell by liquid drop model.

[Biochemical stimulus effects in cell cleavage].

A lot of experimental findings have confirmed that: Animal cells acquire a spherical shape just before the division; Under biochemical stimulus of mitotic apparatus aster the cells form a contractile ring in equator plane, and the mother cell divides into two daughter cells; meanwhile the total volume keeps constant. In Zinemanas and Nir's model the reorientation of microfilament and the visco-elasticity of cortex have been took into consideration. In our present work, the effective coefficient m due to biochemical stimulus was incorporated into the model, and the local distribution C was modified to diffuse with the plasma membrane motion.

[The advance of experimental cell division biomechanics].

The advance of experimental cell division and proliferation in the field of cell biomechanics is presented in this paper. The emphasis is placed on the research in the mechanics mechanism of cleavage furrow and in the measurement of constricting force about cleavage furrow.

[The biomechanical model of cytokinesis in animal cells].

As the basis of cell proliferation, cytokinesis involves the division of the cytoplasm and the plasma membrane into two. In this paper a few models on the active deformation mechanism during cytokinesis process are presented. Discussions are made onvarious models, conclusions, differences between the numerical results and the corresponding experimental results.