scholarly journals Observation of Internal Oscillation in Brackish Lakes with a Neutral Buoy.

1996 ◽  
Vol 57 (4) ◽  
pp. 293-304 ◽  
Author(s):  
Tomoyasu FUJII ◽  
Toshifuni UEDA ◽  
Setsuo OKUDA ◽  
Koji YOKOYAMA
Keyword(s):  
Internal Oscillation ◽  
Brackish Lakes

scholarly journals The mechanism and rate of re-sedimentation of phosphorus released from the sediment during the summer months in shallow brackish lakes

2014 ◽  
Vol 76 (2) ◽  
pp. 139-148 ◽  
Author(s):  
Hiroshi KAMIYA ◽  
Shogo SUGAHARA ◽  
Yuki SAGA ◽  
Sachiko SATO ◽  
Yukari NOJIRI ◽  
...  
Keyword(s):  
Brackish Lakes

Cellular and subcellular mechanisms of cardiac pacemaker oscillations

1979 ◽  
Vol 81 (1) ◽  
pp. 205-215
Author(s):  
R. W. Tsien ◽  
R. S. Kass ◽  
R. Weingart
Keyword(s):  
Membrane Potential ◽  
Voltage Clamp ◽  
Surface Membrane ◽  
Cardiac Pacemaker ◽  
Oscillatory Activity ◽  
Purkinje Fibre ◽  
Pacemaker Activity ◽  
Heart Cells ◽  
Control Loop ◽  
Internal Oscillation

Rhythmic oscillations in the membrane potential of heart cells are important in normal cardiac pacemaker activity as well as cardiac arrhythmias. Two fundamentally different mechanisms of oscillatory activity can be distinguished at the cellular and subcellular level. The first mechanism, referred to as a surface membrane oscillator, can be represented by a control loop in which membrane potential changes evoke delayed conductance changes and vice versa. Since the surface membrane potential is a key variable within the control loop, the oscillation can be interrupted at any time by holding the membrane potential constant with a voltage clamp. This mode of oscillation seems to describe spontaneous pacemaker activity in the primary cardiac pacemaker (sinoatrial node) as well as other regions (Purkinje fibre, atrial or ventricular muscle). In all tissues studied so far, the pacemaker depolarization is dominated by the slow shutting-off of an outward current, largely carried by potassium ions. The second mechanism can be called an internal oscillator since it depends upon a subcellular rhythm generator which is largely independent from the surface membrane. Under voltage clamp, the existence of the internal oscillation is revealed by the presence of oscillations in membrane conductance or contractile force which occur even though the membrane potential is held fixed. The two oscillatory mechanisms are not mutually exclusive; the subcellular mechanism can be preferentially enhanced in any given cardiac cell by conditions which elevate intracellular calcium. Such conditions include digitalis intoxication, high Cao, low Nao, low or high Ko, cooling, or rapid stimulation. Several lines of evidence suggest that the subcellular mechanism involves oscillatory variations in myoplasmic calcium, probably due to cycles of Ca uptake and release by the sarcoplasmic reticulum. The detailed nature of the Cai oscillator and its interaction with the surface membrane await further investigation.

Necklace solitons in Bessel photonic lattice: Stability and internal oscillation

2011 ◽  
Vol 284 (7) ◽  
pp. 1859-1862 ◽  
Author(s):  
Pingyuan Liang ◽  
Bin Xu ◽  
Jianchu Liang ◽  
Zebin Cai
Keyword(s):  
Lattice Stability ◽  
Internal Oscillation

Community structure and diel migration of zooplankton in shallow brackish lakes: role of salinity and predators

Hydrobiologia ◽  
2010 ◽  
Vol 646 (1) ◽  
pp. 215-229 ◽  
Author(s):  
Elisabeth Jensen ◽  
Sandra Brucet ◽  
Mariana Meerhoff ◽  
Louise Nathansen ◽  
Erik Jeppesen
Keyword(s):  
Community Structure ◽  
Diel Migration ◽  
Brackish Lakes
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