The phrase "studies have mentioned" is grammatically correct and can be used in written English.
It is typically used to reference research studies that have been conducted on a particular topic or subject. Example: Studies have mentioned the correlation between regular exercise and improved mental health.
A few previous studies have mentioned nanoparticles coated with protein of natural origin [15].
Some studies have mentioned that electrostatic adhesion can realize large force almost up to 2 N between a fingertip and an electrode by using Johnsen-Rahbeck effect [8].
Several studies have mentioned friction as one of the factors that dissipate the forces in orthodontic treatment [12, 22, 33, 36].
Although these studies have mentioned the DRX optimization problem, they did not consider QoS requirements and aimed to manage the DRX cycle length for UEs to enhance energy efficiency.
For example, few studies have mentioned the different sensitivity of stomatal behaviour to vapour pressure deficit (VPD) in terms of elevated atmospheric CO2 concentrations (Bunce 1998, 2001); [Katul et al. 2009]).
Many studies have used Doppler flowmeters based on an analogue circuit design to obtain the Doppler shifts in the signals backscattered from flowing blood; however, some recent studies have mentioned that the analogue Doppler flowmeter exhibits a frequency-response problem whereby the backscattered energy is lost at higher Doppler shift frequencies.
Only a few studies had mentioned the opening of the inner membrane during the burr-hole evacuation of a CSDH.
Inner membrane opening was discussed during craniotomy for CSDH in many studies [10, 11, 12, 13, 14, 15, 16], but only a few studies had mentioned the opening of the inner membrane during the burr-hole evacuation of a CSDH [17, 18].
Although there are widespread discussions in the literature about maternal request cesareans, most studies had mentioned "the absence of medical indications".
Proton pump inhibitor (PPI) had marketed for more than two decades, and several studies had mentioned its direct link to several enteric infections, such as Clostridium diffcile colitis, Salmonella enteritis [ 4, 5] and spontaneous bacterial peritonitis in patients with advanced cirrhosis [ 6].
To the best of our knowledge, only one previous study has mentioned the level and value of MPs in LC patients [ 27].
