The phrase "are now modified" is correct and usable in written English.
It can be used to indicate that something has been changed or altered in the present time.
Example: "The specifications for the project are now modified to include additional features based on client feedback."
Alternatives: "have now been altered" or "are currently updated".
Thanks to advances in genetic engineering and gene therapy, researchers are now modifying the isolated cells to better attack cancer.
The researchers are now modifying their fabrication process to produce smaller nanoparticles that still have the novel shape.
Traditionally, academic institutions such as the Academy for Systemic Change at MIT have led the field; NGOs like WWF-UK and Forum for the Future are now modifying their strategic approaches, and businesses like Nike and Unilever are also starting to play their part as their markets and supply chains become ever more complex.
The scientists are now modifying the iPOLYMER system so that the hydrogels integrate RNA molecules into their structures, making them better mimics of the stress granules seen in human cells.
"We are very committed to getting this deal done, and are now modifying our offer with the assistance of Pershing Square to increase the economics for all Allergan shareholders".
Gun dealers are now modifying the gun, either converting the Adler back to a seven shot, or offering a "magazine extension tube" so the five shot can become a ten shot.
The concept of probability density frequency, which is successfully used for analyses of wind speed and outdoor temperature distributions, is now modified and proposed for estimating solar radiation distributions for design and analysis of solar energy systems.
The instrument is now modified to search for angular fluctuations and we expect to start taking data this month.
Note, furthermore, that the energetics of the interface, originally comprised of gradient energy and potential, is now modified by the incorporation of an additional term.
