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Soil salinization adversely affects soil quality and ecosystem. Many researches have tried to ameliorate saline soils by soil conditioners. However, little is known about the differences in the responses of soil bacterial communities to natural and artificial conditioners applied to saline soils. Therefore, in this study, the effects of natural humic acid (IK), synthetic polymer (IP), and composite material (IF) (mixture of IK and IP (1:1)) on bacterial community structure and functional genes in saline soil were evaluated to clarify their differences. The results showed that the application of the three soil conditioners significantly reduced soil pH and Na+ content but increased soil alkaline phosphatase, urease, invertase and catalase activities, bacterial diversity, and nutrients, compared to the control (no conditioner). IK application increased bacterial relative abundance (e.g., Subgroup_6, RB41, MND1, and KD4‐96) and metabolic functions (e.g., Two‐component system and Biosynthesis of amino acids) by increasing soil nitrogen and maintaining K+ and Na+ balance. IP application increased soil alkaline phosphatase and urease activities as well as bacterial relative abundance (e.g., Subgroup_6, RB41, MND1, Gemmatimonadaceae, and KD4‐96) and metabolic functions (e.g., Quorum sensing and carbon metabolism) by increasing soil organic carbon/nitrogen content. IF application increased the bacterial relative abundance of Subgroup_6, RB41, and MND1 by increasing soil available nitrogen and regulated their metabolic pathways (e.g., ABC transporters and microbial metabolism). On the whole, IK, IP, and IF could regulate the structure and function of soil bacterial community in saline soils. This study clarifies difference in the effects of different soil conditioners on the amelioration of saline soils from the perspective of soil microbiology, and provides a reference for the amelioration of saline soils in arid areas. [ABSTRACT FROM AUTHOR]

Heavy metal ions have a serious effect on humans and the ecosystem. Molecular sieves have attracted significant attention in heavy metal ion adsorption with distinct microporosity and uniform pore size. In this paper, we successfully synthesized nano-sized NaA molecular sieves in the presence of an organic templating agent while aluminum isopropoxide and silica sol were used as the aluminum and silica sources. To synthesize molecular sieves of the ideal size, the anionic cation concentration and templating agent were adjusted. The findings of Cu(II) and Pb(II) adsorption on NaA molecular sieves showed that under the ideal conditions of adsorption time at 90 minutes, pH = 5, adsorption temperature at 25 °C, and starting adsorbent concentration at 100 mg g−1, the optimal adsorbing capacity could reach 230 mg g−1 and 600 mg g−1, respectively. Isotherm, kinetic, thermodynamic and reusability studies of heavy metal ion adsorption on NaA molecular sieves were carried out to investigate the adsorption kinetics. This work provides a new avenue to regulate the particle sizes of molecular sieves to enhance the adsorption capacity of heavy metal ions. [ABSTRACT FROM AUTHOR]

This paper studies an interval data min–max regret (IDMR) version of the packing-delivery problem, in which a 0-1 knapsack problem is for parcel packing and a capacitated travelling salesman problem is for parcel delivery. The parcel profits for the courier and the tour costs are uncertain and they can take any value from a specific interval with lower and upper bound values. The problem is how to select and deliver a subset of parcels to minimise the maximum regret of net profit which is the difference between the total profits of the selected parcels and the total delivery costs, to deal with the trade-off of the solution robustness and performance. To tackle the problem effectively, we first prove the worst-case scenario of a solution to the problem, based on which, a mixed integer linear programming is formulated. A Benders-like decomposition algorithm is then developed to solve small-scale problems to optimality within the manageable computation time. For medium- and large-scale problems, a simulated-annealing-based heuristic method with a local search procedure is designed. Extensive computational experiments show the efficiency and effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

We consider the robust (min-max regret) version of identical parallel machine scheduling problem, in which jobs may be outsourced to balance total cost against production efficiency. The total cost is measured in terms of the total completion time of jobs processed in-house and the cost of outsourcing the rest. Processing times of in-house jobs are uncertain and they are described as two types of scenarios: discrete and interval. The objective is to obtain a robust (min-max regret) decision that minimises the absolute deviation of total cost from the optimal solution under the worst-case scenario. We first prove the worst-case scenario for any feasible solution. For the interval scenario, we further prove that the maximum regret value can be obtained in polynomial time for any feasible schedule. We also prove that for any discrete scenario, the minimum total cost can be obtained in polynomial time. Since the problem with the interval scenario is strongly NP-hard, we then transform the problem into an equivalent robust single machine scheduling problem. Finally, we develop 2-approximation algorithms for the problem with discrete and interval scenarios, respectively. These results are helpful for bridging the scheduling theory and practice in identical parallel machining environments with outsourcing and uncertain processing times. [ABSTRACT FROM AUTHOR]

Key Features The Tongji Maternal and Child Health Cohort (TMCHC) is a prospective, observational pregnancy and birth cohort study investigating the pre-, peri- and post-natal determinants of mother-child pairs' health, including nutrition, environmental exposes, lifestyle and genetic factors, through the collection of extensive demographics, anthropometric, nutritional and biological data. The first 1000 days of life, the time from pregnancy onset to 2 years of age, is a critical window of opportunity for future health and functioning of mother and child.[[1], [3]] The Tongji Maternal and Child Health cohort (TMCHC), launched in January 2013 in the city of Wuhan, China, is a prospective observational pregnancy and birth cohort that allows a detailed examination of the first 1000 days of life enabling investigation of early-life factors contributing to mother-child pairs' health. The National Natural Science Foundation of China (NSFC 82073555) supports the assessment of maternal folic acid status during pregnancy and genes related to folic acid metabolism for demonstrating their implications on mother and child health. During pregnancy, venous blood samples were obtained at ~16 and 24-28 weeks of gestation, and the day before delivery, when blood tests for Oscar, 75-g oral glucose tolerance test and other clinical-biochemistry tests were performed. [Extracted from the article]