Given a passage with a context and an answer, 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.

[Q]: Context: A fundamental prerequisite for using degradable synthetic biopolymers as composite skin substitutes is the ability to establish vascular tissue. PEGT/PBT block-copolymer matrices have previously been shown as a favorable dermal substitute. In this study, quantitative data on neovascularization of PEGT/PBT block-copolymer matrices are presented.', 'PEGT/PBT-block-copolymer discs of three different pore diameters (1: < 75 microm, 2: 75-212 microm, 3: 250-300 microm) were implanted into dorsal skinfold chambers of balb/c mice. Histological sections were evaluated 7, 14, and 21 days post implantation by light and scanning electron microscopy. Blood vessel analysis was performed by means of digital image analysis (n = 288) of hematoxylin/eosin stained sections within apical (AOF) and basal (BOF) observation fields of the matrices.', 'Twenty-one days after implantation the density of blood vessels within the BOF of the scaffolds with a pore size of 75-212 and 250-300 microm were 4.6 +/- 0.45 and 5.8 +/- 0.62 (mean +/- S.E.M.; blood vessel profiles (BVF)), respectively. In <75 microm scaffolds, smaller numbers of BVF were found (4.2 +/- 0.39). In contrast, the evaluation within the AOF revealed significantly higher numbers of BVF in 75-212 microm group (3.5 +/- 0.49) and 250-300 microm group (4.5 +/- 0.66) as compared to the < 75 microm group (2.3 +/- 0.48).
Answer: There is evidence that the three-dimensional structure of PEGT/PBT-block-copolymer (pore size structure) influences neovascularization. The porous structures of copolymer matrices with adequate interconnection of pores (pore sizes of 75-212 and 250-300 microm) are characterized by faster ingrowth of vascular tissue.
[A]: Does analysis of neovascularization of PEGT/PBT-copolymer dermis substitute in balb/c-mice?


[Q]: Context: To test whether subsensory vibratory noise applied to the sole of the foot using a novel piezoelectric vibratory insole can significantly improve sensation, enhance balance, and reduce gait variability in elderly people, as well as to determine the optimal level of vibratory noise and whether the therapeutic effect would endure and the user's sensory threshold would remain constant during the course of a day.", 'A randomized, single-blind, crossover study of 3 subsensory noise stimulation levels on 3 days.', 'Balance and gait laboratory.', 'Healthy community-dwelling elderly volunteers (N=12; age, 65-90y) who could feel the maximum insole vibration.', 'A urethane foam insole with the piezoelectric actuators delivering subsensory vibratory noise stimulation to the soles of the feet.', 'Balance, gait, and timed Up and Go (TUG) test.', 'The vibratory insoles significantly improved performance on the TUG test, reduced the area of postural sway, and reduced the temporal variability of walking at both 70% and 85% of the sensory threshold and during the course of a day. Vibratory sensation thresholds remained relatively stable within and across study days.
Answer: This study provides proof of concept that the application of the principle of stochastic resonance to the foot sole sensory system using a new low-voltage piezoelectric technology can improve measures of balance and gait that are associated with falls. Effective vibratory noise amplitudes range from 70% to 85% of the sensory threshold and can be set once daily.
[A]: Does a shoe insole delivering subsensory vibratory noise improve balance and gait in healthy elderly people?


[Q]: Context: To evaluate whether the relationship between dietary composition and plasma lipid levels is genetically determined.', 'We have evaluated the influence of common apolipoprotein A5 (APOA5) variants (T-1131 > C, Ser19 > Trp and Val153 > Met) on plasma lipid concentrations in 117 males for whom dietary composition markedly changed and total cholesterol decreased (from 6.21 +/- 1.31 mmol/L in 1988 to 5.43 +/- 1.06 mmol/L in 1996) over an 8 year follow-up study.', 'APOA5 T-1131 > C and Val153 > Met variants did not influence the change in lipid measures over time. In Ser/Ser19 homozygotes, the plasma cholesterol was relatively stable over the years (6.1 +/- 1.2 mmol/L in 1988 and 5.6 +/- 1.0 mmol/L in 1996, -8%, P < 0.01). In contrast, in the Trp19 carriers, the decrease of the plasma cholesterol was more than 20% (6.5 +/- 1.6 mmol/L in 1988 and 5.1 +/- 1.0 mmol/L in 1996) (P < 0.001). The difference of the changes is significant (8% vs. 20%, P < 0.005). Changes in other analyzed lipid parameters have not been significantly associated with APOA5 variants.
Answer: Ser19 > Trp variant in the APOA5 gene may play an important role in an individual's sensitivity to dietary composition.
[A]:
Does aPOA5 variant Ser19Trp influence a decrease of the total cholesterol in a male 8 year cohort?