Clonal Parental Effects on Offspring Growth of Different Vegetative Generations in the Aquatic Plant Pistia stratiotes.

Parental (environmental) effects can modify the growth of offspring, which may play an essential role in their adaptation to environmental variation. While numerous studies have tested parental effects on offspring growth, most have considered offspring growth of only one generation and very few have considered offspring growth of different generations. We conducted a greenhouse experiment with an aquatic clonal plant Pistia stratiotes. We grew a single ramet of P. stratiotes under low or high nutrients, the initial (parent) ramets produced three different generations of offspring ramets, and these offspring ramets were also subjected to the same two nutrient levels. High nutrients currently experienced by the offspring increased biomass accumulation and ramet number of all three offspring generations of P. stratiotes. However, these positive effects on biomass were greater when the offspring ramets originated from the parent ramets grown under low nutrients than when they were produced by the parent ramets grown under high nutrients. These results suggest that parental effects can impact the performance of different offspring generations of clonal plants. However, heavier offspring ramets produced under high nutrients in parental conditions did not increase the subsequent growth of the offspring generations. This finding indicates that parental provisioning in favorable conditions may not always increase offspring growth, partly depending on root allocation but not ramet size such as ramet biomass.

Comparison of efficacy of two different silicone hydrogel bandage contact lenses after T-PRK.

AIM: To compare the efficacy between two different silicone hydrogel bandage contact lenses after transepithelial photorefractive keratectomy (T-PRK). METHODS: In this randomized controlled trial, a total of 89 patients (178 eyes) who underwent T-PRK at the Qingdao Eye Hospital from October to December 2019 were selected. One random eye wore a Senofilcon A bandage contact lens after surgery, and the other eye a Balafilcon A bandage contact lens. Pain scores, uncorrected visual acuity (UCVA), spherical equivalent (SE), corneal epithelial healing status, epithelial thickness, bandage lenses deposits, lenses movement, and ocular surface conditions were measured and compared. RESULTS: There were no differences between the two groups in UCVA, SE, corneal epithelial healing status, corneal epithelial thickness, tear river heights and tear film rupture time at each follow-up visit. However, postoperative pain scores in the Senofilcon A group were significantly lower than those of the Balafilcon A group (F intergroups=67.833, P<0.001; F time=383.773, P<0.001; F interaction=57.344, P<0.001). The duration of pain in eyes in the Senofilcon A group was shorter than that of the Balafilcon A group (t=-3.326, P=0.001). The surface deposition scores and movement scores of Senofilcon A bandage lenses on the first and fourth days after surgery were lower than those of Balafilcon A bandage lenses (Z=-5.385, -6.782, P<0.001; Z=-8.336, -8.906, P<0.001). CONCLUSION: Both Senofilcon A and Balafilcon A bandage lenses have good efficacy after T-PRK. Senofilcon A lenses are associated with less pain and more comfort compared to Balafilcon A.