The phrase "a weak but persistent" is correct and usable in written English.
It can be used to describe something that may not be strong or powerful but continues to exist or occur over time.
Example: "Despite the challenges, there was a weak but persistent hope among the team that they could still achieve their goals."
Alternatives: "a feeble yet enduring" or "a faint but steady".
However, recently this laboratory has proposed that in the presence of PNU-120596, 5 10 µM choline may become effective in producing a weak but persistent activation of α7* nAChRs in hypothalamic tuberomammillary (TM) neurons known to express high densities of functional α7* nAChRs [43].
For example, a weak but persistent activation of α7* nAChRs can be achieved with low concentrations of nicotinic agonists (e.g., ∼1 6 µM 4OH-GTS-21 (i.e., 3- 4-hydroxy, 2-methoxy-benzylidene)anabaseine), a selective α7 nAChR agonist [56], [66]) and has been shown to be neuroprotective in the NGF/serum-withdrawal toxicity model in pheochromocytoma-12 cells expressing functional α7* nAChRs [22].
Therefore, the results of this study suggest that in the presence of PNU-120596, endogenous choline may produce a weak but persistent activation of functional α7* nAChRs in hippocampal CA1 pyramidal neurons and thus, may act as a potent therapeutic agent with potential neuroprotective and cognition-enhancing properties.
And oil prices are set by the weak but persistent OPEC cartel as much as they are by the market.Even so, market forces are already beginning to change the oil industry.
For ash hazard, a 'most likely' eruption scenario was developed, characterised by slow lava extrusion over periods of one to two years with weak but persistent explosions and ash venting up to 3 km.
In terms of ashfall hazards, two alternative scenarios might be adopted as the most likely or expected eruptions, based on an understanding of explosive activity during historic eruptions (e.g. Parks et al. [2012]): these eruptions can be characterized by slow lava extrusion over periods of 2 to 4 years with weak but persistent explosions and ash venting.
The study found weak but persistent effects of IPV on illness signs in Bolivia (OR 1.37, 95%% CI 1.14 1.63) and Peru (OR 1.49, 95%% CI 1.26 1.77), after adjusting for the effects of childcare.
It incorporates the inclined lithologies including a weak interlayer, the persistent and non-persistent faults, and a complex tunnel system.
Secondly, this study demonstrates that in the presence of PNU-120596, physiological levels of choline produce a weak persistent activation of CA1 pyramidal α7* nAChRs and enhance excitability of hippocampal CA1 pyramidal neurons.
In addition to producing a weak persistent activation, synergistic action of 1 µM PNU-120596 plus 5 10 µM choline generated whole-cell responses that were reminiscent of and postulated to be single α7* nAChR ion channel openings detectable in whole-cell patch-clamp configuration [43].
