Q: Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
To investigate the role of the superficial zone in regulating the frictional response of articular cartilage. This zone contains the superficial protein (SZP), a proteoglycan synthesized exclusively by superficial zone chondrocytes and implicated in reducing the friction coefficient of cartilage.', 'Unconfined compression creep tests with sliding of cartilage against glass in saline were carried out on fresh bovine cylindrical plugs (slashed circle 6 mm, n=35) obtained from 16 bovine shoulder joints (ages 1-3 months). In the first two experiments, friction tests were carried out before and after removal of the superficial zone ( approximately 100 microm), in a control and treatment group, using two different applied load magnitudes (4.4 N and 22.2 N). In the third experiment, friction tests were conducted on intact surfaces and the corresponding microtomed deep zone of the same specimen.', 'In all tests the friction coefficient exhibited a transient response, increasing from a minimum value (mu(min)) to a near-equilibrium final value (micro(eq)). No statistical change (P>0.5) was found in micro(min) before and after removal of the superficial zone in both experiments 1 and 2. However, micro(eq) was observed to decrease significantly (P<0.001) after removal of the surface zone. Results from the third experiment confirm that micro(eq) is even lower at the deep zone. Surface roughness measurements with atomic force microscopy (AFM) revealed an increase in surface roughness after microtoming. Immunohistochemical staining confirmed the presence of SZP in intact specimens and its removal in microtomed specimens.
A:
Does removal of the superficial zone of bovine articular cartilage increase its frictional coefficient?