Typhoon-induced stormwater drives nutrient dynamics and triggers phytoplankton blooms in Laizhou Bay, China.

In this study, we investigated the hydrological and ecological impacts of heavy rainfall caused by the storm Rumbia and Typhoon Lekima on Laizhou Bay (LZB) through land‒sea synchronous field surveys, online remote sensors, and simulated enclosure experiments. Within two weeks of Rumbia, approximately 9% and 16% of the annual riverine total nitrogen (TN) and total phosphorus (TP) fluxes, respectively, were transported to the LZB and the proportions were 17% and 35%, respectively, for Lekima. The land use on the watersheds increased the rates of land-derived nutrient loading and altered their biogeochemical forms. Consequently, the average concentrations of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) in the LZB increased by 2.6 and 1.0 times post-Rumbia and by 3.5 and 1.3 times post-Lekima, respectively. Relatively lower salinity and temperature, sudden increases in DIN, and strengthened coastal currents stimulated the growth of highly adaptable and small diatoms, resulting in the first diatom blooms. Subsequently, a bloom of Noctiluca scintillans formed.

Study on load allocation of land-based total nitrogen in the Bohai Sea.

Total nitrogen (TN) is one of the terrigenous pollutants in the Bohai Sea. A reasonable releasing scheme can effectively improve the seawater quality. Based on the observed TN concentrations and the national pollution control requirements, the TN load ratios of four major rivers around the Bohai Sea are adjusted in multiple levels within the range of 50 %-200 % in the frame of total control. Then, a pollutant transport model is used to evaluate each load allocation scheme by calculating the area of different seawater qualities. The optimum scheme is loads of the Yellow River and Luan River are set to 50 % and 200 % of the levels in 2018, and thus the area of heavily polluted seawater can be decreased by 33.14 %. Additionally, the reasonable TN reduction amounts of four major rivers in 2018-2020 are calculated according to the optimum scheme, which can be provided as a decision-making basis of marine managements.

Numerical study of hydrodynamic effects on Manila clam population distribution and transport in the Southwest Laizhou Bay, China.

Pelagic larvae of marine organisms are abundant on many continental shelves. Due to their importance as a biological resource and contribution to marine biodiversity, the dynamics of pelagic larvae have received wide attention. Numerical models are an efficient approach to assessing pelagic larval transport driven by various ocean dynamics. However, few studies have focused on the pelagic larval distribution of Manila clam populations and related dynamic factors in the southwestern Laizhou Bay (SLB) during late spring. A hydrodynamic model including realistic meteorologic and oceanic boundary conditions was coupled with a larval transport model to describe the pelagic larval distribution and transport processes. The hydrodynamic model was validated with observational and satellite-derived data. Effects of hydrodynamics and biological behavior on pelagic dynamics were further simulated with numerical experiments. During the early planktonic period, most clam larvae in the SLB were transported eastward or northeastward. Two potential larval settlement areas (LSAs) were recognized: the east side of the dike outside Guangli port and the Lao River estuary. The dominant controlling factor was southerly wind, and larvae's response to river plume or estuarine circulation played a secondary role. Larval transport depended on bottom subtidal currents when late-stage larvae settled near the bottom layer. The hydrodynamic and larval transport model established in this study can be applied to other bays and coastal waters. Understanding the clam larval distribution and transport dynamics in the SLB can provide a reference for predicting LSAs and biological resource management in coastal aquaculture areas.

Nutrient budgets for the Bohai Sea: Implication for ratio imbalance of nitrogen to phosphorus input under intense human activities.

Eutrophication is a global problem for coastal ecosystems, one that the Bohai Sea (BHS), China, is severely afflicted by due to rapid economic and social development over the last forty years. For sustainable nutrients management in the BHS, comprehensive budgets for Nitrogen (N) and Phosphorus (P) was characterized in 2017, and the relative contributions of river input, submarine fresh groundwater discharge, atmospheric deposition, sediment diffusion, and exchange with the Yellow Sea were quantified. The annual N and P fluxes into the BHS were 362 × 103 t and 10.4 × 103 t, respectively. The terrigenous N inputs occupied the highest proportion, while the largest P input was from sediment diffusion. The ratio of N:P was 77 for total external inputs, while that of the Yellow River was 680; both exceeded the Redfield ratio, indicating an imbalance in the nutrient structure and a P limitation in the BHS.

Compound effect of land reclamation and land-based pollutant input on water quality in Qinzhou Bay, China.

Based on a three-dimensional hydro-biogeochemical model, the compound and individual impacts of two types of human activities, i.e., land reclamation and land-based pollutant input, on coastal water quality were studied. In Qinzhou Bay (QZB), China, a total of 38.90 km2 of tidal flat was reclaimed between 2004 and 2019, and the Chemical Oxygen Demand (COD) in the wastewater was reduced by over 40%. However, the Dissolved Inorganic Nitrogen (DIN) was increased by above 40%, and the Dissolved Inorganic Phosphorus (DIP) was increased by about 17%, leading to the continuous deterioration of water quality in QZB. Correspondingly, the model results show that the bay's average COD decreased by 6.86%, but the DIN and DIP increased by 57.53% and 17.39%, respectively. Considering the individual effects, land reclamation contributed 72.73%, 75.38%, and 25.01% to the changes in the COD, DIN, and DIP concentrations in QZB, respectively; and the remainder was caused by the variations in the land-based pollutant input. By considering the compound effect of these two types of human activities, it was found that land reclamation can hinder the water quality improvement induced by the decrease in land-based pollutant input; and it can intensify the water quality deterioration induced by the increase in land-based pollutant input. These results indicate that the impact of land-based pollutant input on coastal water quality was modulated by land reclamation. However, the modulation did not affect the DIP since the phosphorus was the restrictive element in QZB. The comparison of different experimental results revealed that restoring hydrodynamics to enhance the bay-shelf exchange would be a more effective method of ecological restoration than solely reducing the pollutant input.

Effects of physical exercise on working memory in older adults: a systematic and meta-analytic review.

BACKGROUND: This systematic and meta-analytic review aimed to investigate the effects of physical exercise on the working memory of older adults, and to identify the moderators of these effects. METHODS: We searched six electronic databases for randomized controlled trials on the effects of physical exercise on working memory that were published before or on May 15, 2020. The PEDro scale was used to evaluate the methodological quality of the included studies. Stata 14.0 software was used to perform the meta-analysis, subgroup analysis, and publication bias testing. RESULTS: A total of 28 studies and 2156 participants were included. The methodological quality of the included studies was fair to excellent, and there was no publication bias. Overall, we found that physical exercise had a significant effect on working memory in older adults (standardized mean difference = 0.30, p < 0.0001). The effects of physical exercise on working memory were moderated by exercise frequency, intensity, type, duration, cognitive status, and control subgroup (active/passive), but not by intervention period or age of participant. CONCLUSION: Physical exercise can effectively improve the working memory of older adults. The recommended physical exercise is multi-component exercise or mind-body exercise of moderate intensity for 45-60 min 3 times a week, for more than 6 months.

Hydro-biogeochemical modeling of the early-stage outbreak of green tide (Ulva prolifera) driven by land-based nutrient loads in the Jiangsu coast.

The outbreak of a large-scale green tide (Ulva prolifera) will have a serious impact on marine environment, ecological functions, landscape, and coastal social economy. Eutrophication is generally considered to be the most important driving factor of this phenomenon. It is difficult to obtain the pressure-impact relationship between land-based loading and green tides by only surveying or monitoring, whereas modeling can perform this task easily. In this study, therefore, a hydro-biogeochemical model was established and verified by the measured hydrodynamic and water quality variables. In the initial outbreak area of Jiangsu coast, China, we studied the relationship between U. prolifera bloom and the driving factors of nutrient loads and structures by modeling different scenarios of land source inputs. It was found that the ratio of nitrogen to phosphorus could be affected significantly, which triggered the bloom of U. prolifera. When the land-based input doubled or halved, the dissolved inorganic nitrogen concentration increased 20.6% or decreased 9.5%, respectively, which might result in 14.5% increase or 46.3% decrease in the green tide, respectively. It was also found that the nutrient distribution and structure was affected by the land-based load, which caused the outbreak of U. prolifera. Moreover, the total nutrient load must be controlled to prevent the outbreak of green tide in the Jiangsu coast.

Calculation of city total maximum allocated load of total nitrogen for jurisdictions in Qingdao, China: A water quality-based modeling approach.

This study aims to provide a quantitative basis for the precision emission reduction of land-based total nitrogen (TN) pollutants in Qingdao, China. The total maximum allocated load (TMAL) of TN pollutants within jurisdictions in Qingdao was calculated by using a 3D hydrodynamic-water quality model and a linear programming model. The TMAL includes emission TMAL, point-source and nonpoint source TMAL, TMAL removed by municipal sewage treatment system (MSTS), and soil-retained and water-retained TMAL, which were calculated after the division of source units, establishment of the land-based TN load matrix, simulation of the concentration response matrix, setting of a dissolved inorganic nitrogen (DIN) concentration control standard in the Qingdao coastal area, and calculation of TMAL. In the reliability analysis, a concentration under TMAL was considered to indicate satisfactory water quality criteria (relative standard deviation = 17%, Kappa = 0.55). The results showed that the emission TMAL density of nitrogen pollutants in source units was 1.8 ton/km2/a. Nonpoint and point source-produced TMAL densities were 17.0 ton/km2/a and 5.2 ton/km2/a, respectively. MSTS-removed TMAL density was 12.2 ton/km2/a. Soil- and water-retained TMAL were 4.0 ton/km2/a and 0.7 ton/km2/a, respectively. The summed F(D)∗ proportions of 10 districts were, in descending order, Huangdao (22%), Laoshan (21%), Jimo (18%), Shibei (13%), Licang (7%), Pingdu (7%), Jiaozhou (4%), Shinan (3%), Laixi (3%) and Chengyan (2%).

Thalidomide-based Regimens for Elderly and/or Transplant Ineligible Patients with Multiple Myeloma: A Meta-analysis.

BACKGROUND: Thalidomide is an immunomodulatory and anti-angiogenic drug that has shown promise in patients with myeloma. Trials comparing efficacy of standard melphalan and prednisone (MP) therapy with MP plus thalidomide (MPT) in transplant-ineligible or elderly patients with multiple myeloma (MM) have provided conflicting evidence. This meta-analysis aimed to determine the efficacy and toxicity of thalidomide in previously untreated elderly patients with myeloma. METHODS: Medline, the Cochrane Controlled Trials register, conference proceedings of the American Society of Hematology (1995-2014), the American Society of Clinical Oncology (1995-2014), and CBM, VIP, and CNKI databases were searched for randomized control trials with the use of the medical subject headings "MM " and "thalidomide ". Trials were assessed by two reviewers for eligibility. Meta-analysis was conducted using a fixed effects model. Sensitivity analysis was performed to test the robustness of the findings. RESULTS: Overall, seven trials were identified, covering a total of 1821 subjects. The summary hazard ratio (thalidomide vs. control) was 0.82 (95% confidence interval [CI]: 0.72-0.94) for overall survival (OS), and 0.65 (95% CI: 0.58-0.73) for progression-free survival, in favor of thalidomide treated group. The risk ratio of complete response with induction thalidomide was 3.48 (95% CI: 2.24-5.41). A higher rate of III/IV adverse events were observed in MPT arm compared with the MP arm. However, analysis of sub-groups administering anticoagulation as venous thromboembolism prophylaxis suggested no difference in relative risk of thrombotic events between two arms (RR = 1.47, 95% CI: 0.43-5.07, P = 0.54). Further analysis of trials on the treatment effects of MPT versus MP on adverse events-related mortality showed no statistical difference between two arms (RR = 1.24, 95% CI: [0.95-1.63], P = 0.120). CONCLUSION: Thalidomide appears to improve the OS of elderly and/or transplant-ineligible patients with MM when it is added to standard MP therapy.