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The lithium resources in seawater are more abundant than that on land, which is expected to meet the growing demand for the energy storage device like the lithium batteries. The electrochemical method is regarded as the most potential application. However, this method relies on membranes with advanced lithium-ion selectivity, and the emergence of super ionic conductor is expected to solve this problem. Herein, we employed polymer poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) as the flexible framework and Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 (LATP) as the lithium ion conductor to prepare a flexible LATP/PVDF-HFP composite membrane (FLCM). Optimized FLCM has high lithium-ion selectivity and can be enriched up to 5.525 ppm Li+ in diluted seawater (lithium extraction rate: 4.777 × 10−3 mol/(m2 h)), which is 48.465 times that of commercial cation-exchange membrane (CEM). In addition, the FLCM exhibits excellent equilibrium selectivity for Li + over Ca2+and Mg2+. The selectivity of Li+/Ca2+ and Li+/Mg2+ is up to 8424.706, 853.395, respectively. In an electrocatalytic-driven Li-ion extraction device with four recycle chambers at 2 V voltage, the concentration of Mg2+and Ca2+ in the catholyte can be reduced to 0.744% and 1.249% of the seawater concentration, respectively. The work will be significant to solve the challenges of lithium extraction from seawater. [Display omitted] • LATP/PVDF-HFP composite membrane is flexible owing to the polymer framework. • The FLCM has the outstanding lithium-ion selectivity. • The FLCM exhibits an excellent equilibrium selectivity for Li + over Ca2+and Mg2+. • The lithium-ion extraction from seawater is displayed. [ABSTRACT FROM AUTHOR]

This study examines changes in the local oceanographic and atmospheric conditions over the southern Bay of Bengal and adjacent Indian Ocean waters after the 2004 Indian Ocean tsunami based on satellite remote sensing data and atmospheric reanalysis fields. After the tsunami that occurred on 26 December 2004, the accumulated rainfall had a notably increase (600 mm per month) in January of 2005 over deep waters to the southeast of Sri Lanka. This rainfall increase after the tsunami was accompanied with cooling in the sea surface temperature (SST) (up to −2 °C). Four-day averaged SST anomalies had a noticeable increase (1-4 °C) after the tsunami over the deep waters to the southwest of the epicenter. Series of ocean atmospheric and biological variables changed successively after the change of SST. The chain of causality between the tsunami and the changes in the local atmospheric conditions is suggested. [ABSTRACT FROM AUTHOR]

Relative to the open Northwest Pacific, the basin-scale South China Sea (SCS) is smaller and semi-enclosed, and the impacts of frequent super typhoons on the entire SCS basin have yet to be fully understood. Using multi-satellite observations and reanalysis data, this study explored biophysical responses of the upper ocean of the SCS induced by a typical super typhoon, Mangkhut (2018), and their regional differences with potential mechanisms. There were three different significant-response regions in the whole SCS, as follows: (1) In the ocean area around the typhoon path, strong vertical mixing, upwelling and cooling were induced, resulting in the surface chlorophyll-a (chl-a) concentration enhancing markedly (three-fold). Particularly, asymmetric distribution of typhoon rainfall induced asymmetric sea surface salinity change over along the path the nearshore. Diurnal peak of chl-a concentration increased obviously, and the daily growth rate of chl-a sped up considerably in non-shore areas after Mangkhut's passage. (2) In the Beibu Gulf (BBG), the peripheral winds of Mangkhut caused a change in direction of the sea surface flow field, transporting the high-temperature and high-salinity surface seawater from the southeastern area to the BBG. This induced dramatic increases in sea surface temperature, salinity and height, and a decrease in chl-a, in most areas of BBG. (3) In the southwest SCS, the southwest monsoon–induced eastward offshore upwelling jet was weakened by the opposite large-scale peripheral wind vector of Mangkhut and gradually disappeared, resulting in accumulation and enhancement of chl-a in the nearshore. In addition, Mangkhut peripheral winds also intensified (weakened), shifting the cold (warm) eddy to the north (south) and blocking the horizontal eastward transport belt of the high-concentration chl-a. In general, our present work sheds light on the new evidence that a supper typhoon can cause basin-wide anomalies in the SCS, which has broad implications for marine biophysical environment. Unlabelled Image • Three significant-response regions were identified by multi-satellite observations. • The daily growth rate of chl-a sped up considerably in non-shore areas. • Sea surface salinity near the shore was dominated by asymmetric typhoon rainfall. • Mangkhut-induced horizontal advection altered the environment of Beibu Gulf. • Offshore upwelling in the southwest SCS was affected by the peripheral of Mangkhut. [ABSTRACT FROM AUTHOR]

This study examines how dissolved oxygen (DO) responds to tropical cyclones (TCs) "Wind Pump" in a pre-existing cyclonic and an anticyclonic eddy over the Bay of Bengal (BoB) based on Argo and satellite data. Both TCs induced DO temporal decreases in the subsurface waters (Deep Depression BOB 04 with a pre-existing cyclonic eddy and cyclonic storm Roanu with a pre-existing anticyclonic eddy) owing mainly to the storm-induced upwelling. The deeper oxycline caused by the pre-existing anticyclonic eddy relieved the storm-induced shallow of oxycline during Roanu. On the contrary, the pre-existing cyclonic eddy shoaled the oxycline, intensifying the storm-induced shallow of oxycline during BOB 04. Furthermore, the pre-existing cyclonic eddy induced a long time of DO decrease after BOB 04. This study suggests that the subsurface DO concentrations in the BoB are affected mainly by storm-induced physical processes, and the mesoscale eddies also play an important role., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Effects of tropical cyclones (TCs) on dissolved oxygen (DO) in subsurface waters (20-200 m) over the Oxygen Minimum Zones (OMZs) in the Bay of Bengal (BoB) are examined based on Argo and satellite data. Five TCs (Hudhud, Five, Vardah, Maarutha and Mora) during 2013-2018 are considered. Analyses reveal three types of DO temporal variability caused by the storm-induced mixing and upwelling. The first type features temporal DO increases in subsurface waters (37-70 m) caused mainly by intense vertical mixing and downwelling. The second type features DO reductions in subsurface waters after the storms attributed to storm-induced upwelling. The third type features temporal DO increases at depths between 40 and 79 m and decreases at depths between 80 and 150 m due to the combined effect of strong vertical mixing and upwelling. These three types of DO responses can occur in different areas, depending on TC intensity, translational speed and Ekman pumping. The temporal DO variability is also influenced by the shallow oxycline (58.3 ± 16.7 m), mesoscale eddies and biochemical processes. Due to TC intensification, a pre-existing oceanic cyclonic eddy produced a large upwelling and induced a long time of DO decrease in the subsurface layer. This study suggests three different types of DO responses along the TC track in the OMZ, which is useful to evaluate the influence of TCs on the OMZ., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Purpose: The efficacy of antibiotic prophylaxis for the prevention of surgical site infection (SSI) after breast cancer surgery remains uncertain. The authors of a recent Cochrane meta-analysis based on 15 randomized trials were unable to draw a definitive conclusion. The purpose of this study was to determine the effectiveness of prophylactic antibiotics for the prevention of SSI after breast cancer surgery and the risk factors for SSI., Methods: Breast cancer patients who underwent mastectomy at the authors' institution were enrolled in this study. All the patients give cephazolin by intravenous drip within 1 hour before surgery. Surgical site infection was defined using Centers for Disease Control criteria. Risk factors were abstracted from the electronic medical record. Pearson χ test, Student t test, and multivariable logistic regression were used for the analysis., Results: Four hundred fifty-eight patients undergoing mastectomy were enrolled in this study, including 293 with intravenous drip cephazolin and 165 without. Among them, an overall SSI rate of 6.1% was observed; 4.2% of patients without prophylactic antibiotics developed SSI compared with 7.2% with antibiotics (P = 0.210). Factors associated with SSI were hypertension, diabetes, length of stay (d), age, and length of stay. Weight, duration of surgery, No. of drains, surgical procedure, and type of breast disease were not associated with increased SSI rates., Conclusions: Surgical site infection rates among patients who did and did not receive cephazolin after mastectomy had no significantly different. What is more, the authors should focus on advanced age, hypertension, diabetes, length of stay, and length of stay to decrease development of postoperative SSI rates.

The effects of rainfall and wind speed on the dynamics of suspended sediment concentration (SSC), during the 2004 Indian Ocean tsunami, were analyzed using spatial statistical models. The results showed a positive effect of wind speed on SSC, and inconsistent effects (positive and negative) of rainfall on SSC. The effects of wind speed and rainfall on SSC weakened immediately around the tsunami, indicating tsunami-caused floods and earthquake-induced shaking may have suddenly disturbed the ocean-atmosphere interaction processes, and thus weakened the effects of wind speed and rainfall on SSC. Wind speed and rainfall increased markedly, and reached their maximum values immediately after the tsunami week. Rainfall at this particular week exceeded twice the average for the same period over the previous 4years. The tsunami-affected air-sea interactions may have increased both wind speed and rainfall immediately after the tsunami week, which directly lead to the variations in SSC.