21 research outputs found

    Effect of Sub-Lethal Exposure to Ultraviolet Radiation on the Escape Performance of Atlantic Cod Larvae (Gadus morhua)

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    The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6±0.2 mm; 29 dph, SL: 8.2±0.3 mm) that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments): two-spotted goby (Gobiusculus flavescens; a suction predator) and lion's mane jellyfish (Cyanea capillata; a “passive" ambush predator). Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks ×100), escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38±7.5 mm respectively) were significantly lower than those of control larvae (75%, 69±4.7 mm respectively). There was a significant difference in survival as well (UV: 35%, Control: 63%). No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%, Control: 74%) in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations

    Given breast cancer, does breast size matter? Data from a prospective breast cancer cohort

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    PURPOSE: Body mass index (BMI), waist-to-hip ratio (WHR), and tumor characteristics affect disease-free survival. Larger breast size may increase breast cancer risk, but its influence on disease-free survival is unclear. The purpose of this study was to elucidate whether breast size independently influenced disease-free survival in breast cancer patients. METHODS: Body measurements were obtained preoperatively from 772 breast cancer patients in a population-based ongoing cohort from southern Sweden. The research nurse measured breast volumes with plastic cups used by plastic surgeons doing breast reductions. Clinical data were obtained from patient charts and pathology reports. RESULTS: Patients with a BMI ≥ 25 kg/m(2) had larger tumors (p 0.85 had larger tumors (p = 0.013), more advanced histological grade (p = 0.0016), and more axillary nodal involvement (p = 0.012). Patients with right + left breast volume ≥ 850 mL were more likely to have larger tumor sizes (p = 0.018), more advanced histological grade (p = 0.031), and more axillary nodal involvement (p = 0.025). There were 62 breast cancer events during the 7-year follow-up. Breast volume ≥ 850 mL was associated with shorter disease-free survival (p = 0.004) and distant metastasis-free survival (p = 0.001) in patients with estrogen receptor (ER)-positive tumors independent of other anthropometric measurements and age. In patients with ER-positive tumors, breast size was an independent predictor of shorter disease-free (HR 3.64; 95 % CI 1.42-9.35) and distant metastasis-free survival (HR 6.33; 95 %CI 1.36-29.43), adjusted for tumor characteristics, BMI, age, and treatment. CONCLUSION: A simple and cheap anthropometric measurement with standardized tools may help identify a subgroup of patients in need of tailored breast cancer therapy

    Effect of ultraviolet radiation (UVR) on the life stages of fish

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