"close linkage" is a correct and usable phrase in written English.
You can use it to indicate that two or more things are related in close proximity, or to emphasize the close nature of a relationship between two or more things. Example: "The merger of the two companies created a close linkage between their two teams."
Much of the reason for this close linkage between Islamism and anti-Americanism comes from Iran.
Just a few days earlier the two scientific teams that have deciphered the chemical sequences of the human genome presented their first detailed analyses, making it clear that humans have evolved in close linkage with other species.
Throughout his ruling, Judge Jackson referred to the market power Microsoft derives from the close linkage of Windows with its Office applications software as the "applications barrier to entry" for prospective rivals.
Some of this could be due to close linkage of a non-functional SNP with the functional SNP.
It has a close linkage to land use types and is a reduction factor in soil erosion vulnerability.
Because of the close linkage between assimilation and respiration, elevated CO2 failed to stimulate Asys and Rsys.
The research is important, he says, because scientists recently have uncovered "a close linkage between permafrost and climate," says Vieira.
A single recessive gene, bph2, derived from ASD7 showed close linkage with Bph1 gene and no recombination between them was observed.
It is unclear whether QTL clusters associated with multiple traits represent the pleiotropic effects of a single gene or close linkage of different genes affecting different traits.
Sediments are an important topic for many scientists and regulatory authorities due to their close linkage to the aquatic food web and their potential for accumulating pollutants.
However, the possibility of close linkage of two QTLs for protein content and glossiness of cooked rice in the candidate region of 3.4 Mb cannot be ruled out.
