Ecological impacts of the expansion of offshore wind farms on trophic level species of marine food chain.

The global demand for renewable energy has resulted in a rapid expansion of offshore wind farms (OWFs) and increased attention to the ecological impacts of OWFs on the marine ecosystem. Previous reviews mainly focused on the OWFs' impacts on individual species like birds, bats, or mammals. This review collected numerous field-measured data and simulated results to summarize the ecological impacts on phytoplankton, zooplankton, zoobenthos, fishes, and mammals from each trophic level and also analyze their interactions in the marine food chain. Phytoplankton and zooplankton are positively or adversely affected by the 'wave effect', 'shading effect', oxygen depletion and predation pressure, leading to a ± 10% fluctuation of primary production. Although zoobenthos are threatened transiently by habitat destruction with a reduction of around 60% in biomass in the construction stage, their abundance exhibited an over 90% increase, dominated by sessile species, due to the 'reef effect' in the operation stage. Marine fishes and mammals are to endure the interferences of noise and electromagnetic, but they are also aggregated around OWFs by the 'reef effect' and 'reserve effect'. Furthermore, the complexity of marine ecosystem would increase with a promotion of the total system biomass by 40% through trophic cascade effects strengthen and resource partitioning alternation triggered by the proliferation of filter-feeders. The suitable site selection, long-term monitoring, and life-cycle-assessment of ecological impacts of OWFs that are lacking in current literature have been described in this review, as well as the carbon emission and deposition.

1064†nm InGaAs metamorphic laser power converts with over 44% efficiency.

InGaAs metamorphic laser power converters (LPCs) have the potential to deliver electrical energy over distances of several kilometers. In this study, metalorganic chemical vapor deposition (MOCVD) was used to grow InGaAs-based LPCs with an absorption wavelength of 1064 nm. At step thicknesses of 2800 nm, overshoot thicknesses of 6000 nm, reverse component and thicknesses of 2.4% and 700 nm, respectively, a surface roughness of 6.0 nm and InGaAs (24%) lattice relaxation of 93.7% of the InGaAs metamorphic buffer were obtained. The I-V characteristics of LPCs with 10 × 10 mm2 apertures were investigated as a function of laser power and temperature. The maximum conversion efficiency of 44.1% and 550 hours of continuous stable operation at 4 W were demonstrated. Under 1064 nm laser illumination of 4 W, the temperature coefficients for the conversion efficiency and open-circuit voltage were -0.1%abs/°C and -1.6 mV/°C, respectively, and the LPC output power fluctuation was less than 0.5% during 216 hours of continuous temperature change from 20 to 100°C.

High-performance laser power converts for direct-energy applications.

Six-junction GaAs laser power converts (LPCs) were designed and fabricated. Each subcell is vertically connected by p++-AlGaAs: C/n++-AlGaAs: Si: Te (1:2) tunnel junction with good thermal stability and a record peak tunneling current density of 1867 A/cm2. The I-V characteristics of LPCs with an aperture of 10×10 mm2 were investigated as a function of laser power and temperature. Maximum conversion efficiency and output power of 57.7% and 15.4 W, respectively, and a continuous stable operation at 22.9 W for over 550 hours were demonstrated. The temperature coefficient of conversion efficiency and open-circuit voltage were -0.197%abs/°C and -8.15 mV/°C, respectively, under 808 nm laser illumination of 21.0 W. Furthermore, an array of 100 large-scale (41×46 mm2) LPCs with an output power of 179 W under 1 kW laser irradiation at 20 m wireless transmission was developed.

Relationship between water quality, heavy metals and antibiotic resistance genes among three freshwater lakes.

Urban recreational lakes are impacted by consistent anthropogenic activities and are significant sources of heavy metals and antibiotic resistance genes (ARGs). In this study, three urban lakes of varying size and anthropogenic impact in Nanjing, China, were investigated for the abundance of ten ARGs, six physicochemical factors and four heavy metals. Correlations between heavy metals and physicochemical parameters against ARGs were performed to investigate the presence of ARGs in the lakes. The water quality data indicated that the lakes were on par with levels 3 and 4 of the Chinese surface water environmental standards, signifying disturbing pollution levels in the lakes. The lakes were dominant with high amounts of sul1, sul2 and strA genes, and the sum of these three genes appropriated over 38.9-84.4% in all three lakes, while the sum of tetM, tetQ and ermB genes occupied a minor proportion (0.1-1.4%). High levels of vancomycin resistance genes were found in the three lakes. Spearman analysis indicated that Chlα, cadmium, lead and copper had a significant positive correlation with sul2 and strB. The results of redundancy analysis displayed that Chlα and co-selection with certain heavy metals were the major factors driving the propagation of specific genes in three lakes. We believe our study contributes by adding further knowledge to existing antibiotic resistance gene abundance studies in recreational urban lakes with significant anthropogenic impacts.

Estrogen therapy before hysteroscopic adhesiolysis improves the fertility outcome in patients with intrauterine adhesions.

PURPOSES: To describe the fertility outcomes after hysteroscopic adhesiolysis combined with preoperative hormone treatment in women with intrauterine adhesion (IUA). METHODS: This study is a retrospective cohort study. A total of 230 patients with IUA underwent hysteroscopic adhesiolysis combined with hormone treatment from Jan 2012 to Jun 2018. 148 patients who received preoperative estrogen treatment were enrolled into group A and 82 patients without preoperative estrogen treatment were enrolled into group B. All the patients underwent hysteroscopic adhesiolysis and received postoperative estrogen therapy, intrauterine indwelling device. Second or third look was performed after 2-3 months. RESULTS: 90.87% (209/230) patients complete the study. The AFS scores at baseline were higher in the group A than group B. After the preoperative E2 treatment, group A achieved the comparable AFS score to group B before the surgery. The cumulative fertility rate in group A was comparable in group B, both in the ITT analysis (49.32% vs. 52.44%, p = 0.651) and the PP analysis (54.07% vs.58.10%, p = 0.575).The mean conception time was also similar in group A and group B (8.30 ± 6.47 vs. 8.54 ± 5.68 months, p = 0.837). Besides, the surgery times in group A were less than group B. There was no difference in the rate of adverse events between two groups. CONCLUSIONS: Hysteroscopic adhesiolysis combined with preoperative oestrogen could reduce the preoperative AFS scores and the times of surgery which yield a similar conception rate in women with less severe intrauterine adhesions.