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Correlation has become a fundamental method for information science. However, correlations are limited in making concrete decisions. In this article, we detail how causal inference could be utilised in the field of information science. There are six main steps of implementing matching for causal inference, namely, selecting candidate control variables, determining control variables, calculating similarities among all samples, forming control group, examining the performance of control group and estimating causal effects. As an example, this article applies causal inference to investigate whether Nobel Physics award increases the after-award citations. The method is presented in a step-by-step manner so that researchers can reproduce our analysis in the future.

The purposes of this study were to analyse the spatiotemporal variations in greenhouse gas diffusive fluxes at the sediment–water interface of sewage-draining rivers and natural rivers, and investigate the factors responsible for the changes in greenhouse gas diffusive fluxes. Greenhouse gas diffusive fluxes at the sediment–water interface of rivers in Tianjin city (Haihe watershed) were investigated during July and October 2014, and January and April 2015 by laboratory incubation experiments. The influence of environmental variables on greenhouse gas diffusive fluxes was evaluated by Spearman’s correlation analysis and a multiple stepwise regression analysis. Sewage-draining rivers were more seriously polluted by human sewage discharge than natural rivers. The greenhouse gas diffusive fluxes at the sediment–water interface exhibited obvious spatiotemporal variations. The mean absolute value of the CO2 diffusive fluxes was seasonally variable with spring>winter>fall>summer, while the mean absolute values of the CH4 and N2O diffusive fluxes were both higher in summer and winter, and lower in fall and spring. The annual mean values of the CO2, CH4 and N2O diffusive fluxes at the sewage-draining river sediment–water interface were − 123.26 ± 233.78 μmol m−2 h−1, 1.88 ± 6.89 μmol m−2 h−1 and 1505.03 ± 2388.46 nmol m−2 h−1, respectively, which were 1.22, 4.37 and 134.50 times those at the natural river sediment–water interface, respectively. The spatial variation of the N2O diffusive fluxes in the sewage-draining rivers and the natural rivers was the most significant. As a general rule, the more serious the river pollution was, the greater the diffusive fluxes of the greenhouse gases were. On average for the whole year, the river sediment was the sink of CO2 and the source of CH4 and N2O. There were positive correlations among the CO2, CH4 and N2O diffusive fluxes. The main influencing factor for CO2 and N2O diffusive fluxes was the water temperature of the overlying water; however, the key factors for CH4 diffusive fluxes were the Eh of the sediment and the NH4+-N of the overlying water. River sediment can be either a sink or a source of greenhouse gases, which varies in different levels of pollution and different seasons. Human sewage discharge has greatly affected the carbon and nitrogen cycling of urban rivers.

Organophosphate esters (OPEs) are normally used as flame retardants, plasticizers and lubricants, but have become environmental pollutants. Because OPEs are normally present alongside heavy metals in soils, the effects of interactions between OPEs and heavy metals on plant uptake of OPEs need to be determined. In this study, we investigated the effects of OPEs chemical structure, plant cultivar and copper (Cu) on the uptake and translocation of OPEs by plants. The bioaccumulation of OPEs varied among plant cultivars. They were preferentially enriched in carrot, with the lowest concentrations observed in maize. OPEs with electron-ring substituents (ER-OPEs) exhibited a higher potential for root uptake than did OPEs with open-chain substituents (OC-OPEs), which could be attributed to the higher sorption of ER-OPEs onto root charged surfaces. This was explained by the stronger noncovalent interactions with the electron-rich structure of ER-OPEs. The presence of Cu slightly reduced the distinct difference in the ability of roots to take up OC-OPEs and ER-OPEs. This was explained by the interactions of Cu ions with the electron-rich structure of ER-OPEs, which suppressed the sorption of ER-OPEs on the root surface. A negative relationship between the logarithms of the translocation factor and octanol-water partition coefficient (Kow) was observed in treatments with either OPEs only or OPEs + Cu, implying the significant role of hydrophobicity in the OPEs acropetal translocation. The results will improve our understanding of the uptake and translocation of OPEs by plant cultivars as well as how the process is affected by the chemical structure of OPEs and Cu, leading to improvements in the ecological risk assessment of OPEs in the food chain.

Beibei Hu,1,2 Jianxin Wang,3 Jing Li,3 Sanming Li,3 Heran Li1 1School of Pharmacy, China Medical University, Shenyang 110122, People’s Republic of China; 2College of Chemistry and Pharmaceutical Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, People’s Republic of China; 3School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, People’s Republic of ChinaCorrespondence: Heran LiSchool of Pharmacy, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang 110122, People’s Republic of ChinaTel +86 13897945866Email liheranmm@163.comPurpose: The purpose of this research was to study the basic physicochemical and biological properties regarding the application of L-tartaric acid modified chiral mesoporous silica nanoparticle (CMSN) as a drug carrier, and to explore the structure–property relationship of silica-based materials.Methods: CMSN with functions of carboxyl modification and chirality was successfully synthesized through co-condensation method, and the basic characteristics of CMSN, including morphology, structure, wettability, degradation, bio-adhesion and retention ability in gastrointestinal tract (GI tract) were estimated by comparing with non-functionalized mesoporous silica nanoparticles (MSN). Meanwhile, the biocompatibility and toxicity of L-tartaric modification were systematically evaluated both in vitro and in vivo through MTT cell viability assay, cell cycle and apoptosis assay, hemolysis assay, histopathology examination, hematology analysis, and clinical chemistry examination.Results: CMSN and MSN were spherical nanoparticles with uniform mesoporous structure. CMSN with smaller pore size and carboxyl functional groups exhibited better wettability. Besides, CMSN and MSN could dissolve thoroughly in simulated physiological fluids during a degradation period of 1– 12 weeks. Interestingly, the in vitro and in vivo behaviors of carriers, including degradation, bio-adhesion and retention ability in the GI tract were closely related to wettability. As expected, CMSN had faster degradation rate, higher mucosa-adhesion ability, and longer retention time. Particularly, CMSN improved the bio-adhesion property in both gastric mucosa and small intestinal mucosa, and prolonged the GI tract retention time to at least 12 h, which meant higher probability for absorption. The biocompatibility and toxicity examination indicated that CMSN was a kind of biocompatible bio-material with good blood compatibility and negligible toxicity, which is required for further applications in biological fields.Conclusion: CMSN with functions of carboxyl modification and chirality had superiority in terms of both physicochemical and biological properties. The in vitro and in vivo behaviors of carriers, including degradation, bio-adhesion, and retention were closely related to wettability.Keywords: chiral mesoporous silica, carboxyl modification, wettability, bio-adhesion, biocompatibility

Existing methods for the sustainability assessment of industrial production processes have considered the values of natural resource use and ecosystem services. However, these methods mainly focus on monetary measures of natural capital cost and ignore some other costs, including human health effects, biodiversity loss and indirect exergy consumption in labor employment. The integrated ecological cumulative exergy consumption accounting method was proposed to improve the existing extended exergy model and provide a comprehensive perspective of the full cost of production including natural resources, human resources and environmental cost. The improved model is illustrated by its application for the steel-making process in China. Of the total cost of the steel-making process, the human resources cost (investment) accounts for only 9.7%. Contrary to the traditional cost evaluation, the result of this case study shows that classical economic assessment cannot reflect an overall ecological sustainable level of the steel-making process. The integrated method framework can be used to assess sustainability in a different spatial scale.

The distribution of high-quality customers (hereafter HQC) for taxis (including ride-hailing cars) has a significant impact on drivers’ revenue and taxis’ operation efficiency. Based on the taxi global positioning system data, we construct an evaluation model of passengers to discuss the imbalance of consumption in taxi market. The profit margin for each taxi order is calculated, and then a grid-based method is used to distinguish the HQC and the regions with potential higher benefits. We analyze the HQC’s distribution of taxis (including ride-hailing cars) in different areas and in different time periods. We find that the HQC are distributed mainly on the periphery of the main urban area, which indicates that traffic condition is even worse in the urban center because of factors such as congestion. The HQC are more concentrated on workdays and more scattered on nonworkdays, which implies that the public have different travel habits and demands on workdays and nonworkdays. The proportion of HQC in each administrative district or functional zone is not always positively correlated to either the proportion of total orders or the total HQC. This indicates that the distribution of HQC in each administrative district or functional zone is imbalanced. The proportion of orders and that of HQC are roughly the same in the temporal dimension, being higher in the morning and evening rush hours. Compared with the distribution of the HQC of ride-hailing, that of taxis is more imbalanced in the temporal dimension. Relevant departments should further coordinate taxi pricing, strengthen market control, and promote sustainable development in the taxi and ride-hailing markets.

Coastal wetland losses in China are globally-relevant issues, as formerly sequestered soil organic carbon is released as CO2 into the atmosphere. Wetland losses also reduce the primary production by plants that would otherwise bury carbon in the future. More than 50% of these ecosystems have been lost globally over the last half century, with this number approaching 58% in China. The negotiation of international accords such as the Paris Climate Agreement rely on the accurate assessment of ecosystem-held carbon quantities. Our objective was to provide the first national scale survey of coastal wetland-based carbon in China. The average soil organic carbon stock (Mg SOC ha−1) across all three types of ecosystems was 236.91, with an average of 344.67 for mangroves, 175.14 for seagrass, and 134.37 for salt marshes. The SOC stock was greatest at 30–60 cm of depth in the case of mangroves, as opposed to 0–20 cm of depth for salt marshes. In terms of the carbon content of the standing aboveground and belowground biomass (Mg C ha−1), mangroves contained by far the most with an average of 253.98 and 83.96, respectively. Carbon burial rates, or the annual flux of SOC into the soil column (Mg C ha−1 yr−1), were 2.26 ± 0.39 for mangroves, 1.38 ± 0.38 for seagrass, and 2.18 ± 0.24 for salt marshes. Through our work, we found a total of 48.12–123.95 Tg of C in China's coastal wetlands (down to 1 m of soil column depth), with an annual burial of 0.84 Tg yr−1. We estimate the average annual emissions of CO2 to be on the order of 6.83 Tg CO2 yr−1, due to ongoing and extensive wetland loss and conversion.

In this work, we probe the initial-boundary value problem of the Kundu-Eckhaus (KE) equation on the half-line by using of the Fokas unified transform approach. The solution of KE equation c...

(R)-3-aminopiperidine ((R)-APD), a key intermediate for alogliptin, trelagliptin, and linagliptin, was successfully resolved from racemic 3-aminopiperidine with an enantiomerically pure resolving agent, namely, (R)-4-(2-chlohydroxy-1.3.2-dioxaphosphorinane 2-oxide ((R)-CPA), via diastereomeric salt formation. By this resolution approach, (R)-3-aminopiperidine was obtained in 99.5% yield with 99.6%e.e.

With the rapid development of urbanization, the blind expansion of urban space has led to a series of social problems. In this process, the degree of urban function mixing affects the urbanization development level, making it particularly important to study the degree of coupling coordination between the two aspects. In this paper, taking Beijing as an example, we use urban point of interest (POI) data and taxi GPS trajectory data to calculate the urban POIs&rsquo, spatial entropy and taxis&rsquo, temporal entropy, based on the information entropy. We use the POIs&rsquo, temporal entropy to measure the urban function mixing degree. Also, the model of coupling coordination degree is used to measure the degree of coupling coordination between the urban function mixing degree and the urbanization development level. The results indicate the following: First, the POIs&rsquo, temporal entropy have significant regional imbalances. On the whole, both show a declining pattern when moving from the central urban area to the outer suburbs. The urban function mixing degree and urbanization development level are also higher in the central urban area than in the outer suburbs. Second, the coupling coordination among the urbanization development level, POIs&rsquo, spatial entropy, and taxis&rsquo, temporal entropy is distributed unevenly across various regions, which means that the three types of coupling coordination are in balanced development in the central urban area, but in unbalanced development in the outer suburbs. Third, from the perspective of spatial correlation characteristics, the higher is the degree of spatial agglomeration, the higher are the urban function mixing degree and urbanization development level, and the higher is the coupling coordination degree among the urbanization development level, POIs&rsquo, temporal entropy. Therefore, relevant departments should plan the construction of urban functional areas reasonably, according to the degree of coupling coordination between the urban function mixing degree and the urbanization development level in different regions, so as to realize the healthy and sustainable development of a city.

The emergence and development of car-sharing has not only satisfied people&rsquo, s diverse travel needs, but also brought new solutions for improving urban traffic conditions and achieving low-carbon and green sustainable development. In recent years, car-sharing has had competition with other ways of getting around, as the acceptance of car-sharing has grown, notably taxis. Therefore, it is particularly important to explore car-sharing travel costs advantages from the perspective of consumers and discover the competitive and complementary spaces between car-sharing and other modes. Therefore, taking Beijing as an example, this paper uses GPS trajectory data based on car-sharing orders to design a travel cost framework of car-sharing and taxis. We calculate and compare the travel cost difference between these two modes under different travel characteristics. The results indicate that car-sharing is a more economical way for consumers to travel for short or medium lengths of time, while people are more inclined to take taxis for distances of long duration. Compared with on workdays, at the weekend, the cost advantage of car-sharing is greater for long-distance trips. Moreover, the cost advantage of car-sharing increases gradually with the increase in travel distance. In addition, the travel costs of car-sharing and taxis are also affected by peak and off-peak traffic periods. Compared with off-peak periods, it is more cost-effective for travelers to take taxis during peak traffic periods for various travel distances. From the perspective of the travel cost, it is of great theoretical significance to discuss the substitution (market competition) and complementary relationship (market cooperation) between car-sharing and taxis in a detailed and systematic way. It provides methods and ideas for the comparative cost calculation of car-sharing and other travel modes. This paper also provides enlightenment and guidance for the development of car-sharing. Enterprises should implement differentiated pricing, designing different charging methods for different traffic periods, travel miles, and rental times, and set up additional stations in the surrounding areas of the city. Relevant government departments should also strictly manage the market access of car-sharing, and add or open car-sharing parking lots in centralized areas and for specific periods.

The distribution and composition of polychlorinated biphenyls (PCBs) within soil-plant systems around a notorious e-waste recycling site were investigated. The average total PCB concentrations in rhizospheric soils (RSs) and nonrhizospheric soils (NRSs) were 2160 and 1270 pg g

Toxic heavy metals and metalloids in agricultural ecosystems are crucial factors that limit global crop productivity and food safety. Industrial toxic heavy metals and metalloids such as cadmium, lead, and arsenic have contaminated large areas of arable land in the world and their accumulation in the edible parts of crops is causing serious health risks to humans and animals. Plants have co-evolved with various concentrations of these toxic metals and metalloids in soil and water. Some green plant species have significant innovations in key genes for the adaptation of abiotic stress tolerance pathways that are able to tolerate heavy metals and metalloids. Increasing evidence has demonstrated that phytohormone abscisic acid (ABA) plays a vital role in the alleviation of heavy metal and metalloid stresses in plants. Here, we trace the evolutionary origins of the key gene families connecting ABA signaling with tolerance to heavy metals and metalloids in green plants. We also summarize the molecular and physiological aspects of ABA in the uptake, root-to-shoot translocation, chelation, sequestration, reutilization, and accumulation of key heavy metals and metalloids in plants. The molecular evolution and interaction between the ABA signaling pathway and mechanisms for heavy metal and metalloid tolerance are highlighted in this review. Therefore, we propose that it is promising to manipulate ABA signaling in plant tissues to reduce the uptake and accumulation of toxic heavy metals and metalloids in crops through the application of ABA-producing bacteria or ABA analogues. This may lead to improvements in tolerance of major crops to heavy metals and metalloids.

In this work, we investigate the two-component modified Korteweg-de Vries (mKdV) equation, which is a complete integrable system, and accepts a generalization of 4 × 4 matrix Ablowitz–Kaup–Newell-Segur (AKNS)-type Lax pair. By using of the unified transform approach, the initial-boundary value (IBV) problem of the two-component mKdV equation associated with a 4 × 4 matrix Lax pair on the half-line will be analyzed. Supposing that the solution {u1(x, t), u2(x, t)} of the two-component mKdV equation exists, we will show that it can be expressed in terms of the unique solution of a 4 × 4 matrix Riemann–Hilbert problem formulated in the complex λ-plane. Moreover, we will prove that some spectral functions s(λ) and S(λ) are not independent of each other but meet the global relationship.

The first umpolung strategy for the cycloacylation of fullerene using a N-heterocyclic carbene organocatalyst is reported. The coupling of [60]fullerene with different structural α,β-unsaturated aldehydes efficiently furnishes interesting [60]fullerene-fused cyclopentan-1-ones or cyclohex-2-en-1-ones in good to excellent yields. This new reaction displays a wide substrate scope and excellent functional-group tolerance, and diverse substituents such as aryl, heteroaryl, alkenyl, alkyl, and ester can be installed by using the corresponding enals.

We theoretically study the fiber-coupling efficiency of Gaussian–Schell model beams propagating through oceanic turbulence. The expression of the fiber-coupling efficiency is derived based on the spatial power spectrum of oceanic turbulence and the cross-spectral density function. Our work shows that the salinity fluctuation has a greater impact on the fiber-coupling efficiency than temperature fluctuation does. We can select longer λ in the “ocean window” and higher spatial coherence of light source to improve the fiber-coupling efficiency of the communication link. We also can achieve the maximum fiber-coupling efficiency by choosing design parameter according specific oceanic turbulence condition. Our results are able to help the design of optical communication link for oceanic turbulence to fiber sensor.

Degradation properties play a vital role in long-term in situ drug delivery systems. In vitro degradation behaviours of organogels were investigated via two approaches in this study: a weight loss method and a drug release method. Through the two methods, parameters that affect the degradation of organogels (such as gelator type, gelator concentration and oil type) were systematically tested under a lipase solution to better mimic in vivo circumstances. The gelator structure had the greatest influence on degradation behaviour. By regulating the parameters that influence degradation, the drug release method can properly predict in vivo degradation. Our investigation of organogel degradation provides a theoretical basis for in vivo organogel use as a biodegradable in situ implant for drug delivery.

Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) concentration, saturation and fluxes in rivers (Beitang drainage river, Dagu drainage rive, Duliujianhe river, Yongdingxinhe river and Nanyunhe river) of Tianjin city (Haihe watershed) were investigated during July and October in 2014, and January and April in 2015 by static headspace gas chromatography method and the two-layer model of diffusive gas exchange. The influence of environmental variables on greenhouse gases (GHGs) concentration under the disturbance of anthropogenic activities was discussed by Spearman correlative analysis and multiple stepwise regression analysis. The results showed that the concentration and fluxes of CO2, CH4 and N2O were seasonally variable with >winter>fall>summer, spring>summer>winter>fall and summer>spring>winter>fall for concentrations and spring>summer>fall>winter, spring>summer>winter>fall and summer>spring>fall>winter for fluxes respectively. The GHGs concentration and saturation were higher in comprehensively polluted river sites and lower in lightly polluted river sites. The three GHGs emission fluxes in two sewage draining rivers of Tianjin were clearly higher than those of other rivers (natural rivers) and the spatial variation of CH4 was more obvious than the others. CO2 and N2O air-water interface emission fluxes of the sewage draining rivers in four seasons were about 1.20-2.41 times and 1.13-3.12 times of those in the natural rivers. The CH4 emission fluxes of the sewage draining rivers were 3.09 times in fall to 10.87 times in spring of those in the natural rivers in different season. The wind speed, water temperature and air temperature were related to GHGs concentrations. Nitrate and nitrite (NO3-+NO2--N) and ammonia (NH4+-N) were positively correlated with CO2 concentration and CH4 concentration; and dissolved oxygen (DO) concentration was negatively correlated with CH4 concentration and N2O concentration. The effect of human activities on carbon and nitrogen cycling in river is great.

We present the models of the Strehl ratio (SR) and the spread rate of Gaussian–Schell model (GSM) beams in the long slant path of marine–atmosphere turbulence. The models are developed based on the extended Rytov theory which permits us extending the results of weak scintillation into the moderate-to-strong scintillation regimes. Our results show that there exists a minimum of SR for selected waist radiuses and the minimum SR is dependent on the transverse coherent width of light source. The spread rate increases with increasing the light wavelength but it decreases with increasing the waist radius and the inner scale. The effects of turbulence on the peak received irradiance can be reduced by selecting larger waist radius of transmitting aperture and longer light wavelength.

The total area of wetlands in China is 53.42 × 106 ha, accounting for 10% of global wetlands and 5.58% of China's territorial area. Wetlands in China are constantly under serious threat from multiple influencing factors. A large number of wetlands have been destroyed and degraded since the 1950s. During past decades, China has already recognized the importance of wetland ecosystems and made many efforts in wetland conservation. More than 550 National Wetland Nature Reserves and 100 National Wetland Parks have been established. However, in the context of so much effort being done, the annual wetland disappearance rate is still close to 1%. In this paper, the current status of wetland resources was reviewed, and the impact factors of wetland degradation were discussed. We further discussed the weaknesses of the current management system. Furthermore, some key recommendations for improvement of wetland protection and management for China were given. These recommendations include: improve special laws and regulations regarding wetlands, establish specialized management agencies; strengthen wetlands research and monitoring; and enhance public wetland conservation awareness.

The bit-error rate (BER) and outage probability of optical wireless communication (OWC) link for the ground-to-train of the curved track in turbulence with rain is evaluated. Considering the re-modulation effects of raining fluctuation on optical signal modulated by turbulence, we set up the models of average BER and outage probability in the present of pointing errors, based on the double inverse Gaussian (IG) statistical distribution model. The numerical results indicate that, for the same covered track length, the larger curvature radius increases the outage probability and average BER. The performance of the OWC link in turbulence with rain is limited mainly by the rain rate and pointing errors which are induced by the beam wander and train vibration. The effect of the rain rate on the performance of the link is more severe than the atmospheric turbulence, but the fluctuation owing to the atmospheric turbulence affects the laser beam propagation more greatly than the skewness of the rain distribution. Besides, the turbulence-induced beam wander has a more significant impact on the system in heavier rain. We can choose the size of transmitting and receiving apertures and improve the shockproof performance of the tracks to optimize the communication performance of the system.

Evasion of carbon dioxide (CO2) and methane (CH4) in streams and rivers play a critical role in global carbon (C) cycle, offsetting the C uptake by terrestrial ecosystems. However, little is known about CO2 and CH4 dynamics in lowland coastal rivers profoundly modified by anthropogenic perturbations. Here, we report results from a long-term, large-scale study of CO2 and CH4 partial pressures (pCO2 and pCH4) and evasion rates in the Shanghai river network. The spatiotemporal variability of pCO2 and pCH4 were examined along a land-use gradient and the annual CO2 and CH4 evasion were estimated to assess its role in regional C budget. During the study period (August 2009 – October 2011), the overall mean pCO2 and median pCH4 from 87 surveyed rivers were 5846±2773 μatm and 241 μatm, respectively. Internal metabolic CO2 production and DIC input via upstream runoff were the major sources sustaining the widespread CO2 supersaturation, coupling pCO2 to biogeochemical and hydrological controls, respectively. While CH4 was oversaturated throughout the river network, CH4 hotpots were concentrated in the small urban rivers and highly discharge-dependent. The Shanghai river network played a disproportionately important role in regional C budget, offsetting up to 40% of the regional terrestrial net ecosystem production (NEP) and 10% of net C uptake in the river-dominated East China Sea fueled by anthropogenic nutrient input. Given the rapid urbanization in global coastal areas, more research is needed to quantify the role of lowland coastal rivers as a major landscape C source in global C budget.

A novel bolaamphiphile surfactant N,N'-(dodecane-1, 12-diyl) bis (2,6-diaminohexanamide) (DADL) was designed and synthesized using l-lysine and 1,12-diaminododecane as the hydrophilic and hydrophobic part, respectively. After separation and purification, the structure of the synthetic bolaamphiphile surfactant was verified by FTIR, MS and 1H NMR. The synthetic bolaamphiphile was able to self-assemble to form vesicles. After formulation screening, vesicles loaded with 5-Fluorouracil (5-Fu) were prepared with Tween 60 and DADL by sonication and were examined by dynamic light scattering and transmission electron microscopy. Micro-FTIR was applied to investigate the conformation of the bola molecules within the vesicle membrane. The release profile of the vesicles showed a pH-sensitive and sustained release. No significant toxicity was observed in an in vitro cell viability assay. The antitumor efficacy of the 5-Fu-loaded vesicles on H22 tumor-bearing mice was remarkably high due to the EPR effects. These results show that our novel bolaamphiphile derived from lysine has excellent potential as a pH-sensitive drug carrier.

The super integrable system and its super Hamiltonian structure are established based on a loop super Lie algebra and super-trace identity in this paper. Then the super integrable system with self-consistent sources and conservation laws of the super integrable system are constructed. Furthermore, an explicit Bargmann symmetry constraint and the binary nonlinearization of Lax pairs for the super integrable system are established. Under the symmetry constraint,the n $n$ -th flow of the super integrable system is decomposed into two super finite-dimensional integrable Hamilton systems over the supersymmetric manifold. The integrals of motion required for Liouville integrability are explicitly given.

Coastal reclamation is the gain of land from the sea or coastal wetlands for agricultural purposes, industrial use or port expansions. Large-scale coastal land reclamation can have adverse effects on the coastal environment, including loss of marine habitats and deterioration of coastal water quality. In recent decades, coastal land reclamation has occurred extensively to meet the increasing needs of rapid economic development and urbanization in China. The overall objective of this study is to understand the coastal reclamation status of China from 1979 to 2014 and analyzed its driving factors for mitigating negative ecological effects. The data of coastal reclamation were done with the ERDAS Imagine V9.2 platform and ArcGIS software based on remote images including Landsat, SPOT, ZY-2 and ZY-3. Potential driving factors for sea reclamation were selected based on statistics bulletins and the knowledge of experts in coastal management. In order to understand the relationships among possible impact factors and coastal reclamation, the Partial Least-Squares Regression models was constructed. The analysis results indicated that the total area of reclamation was 11162.89 km2 based on remote sensing images between 1979 and 2014. Shandong Province is the largest reclamation area, reaching 2736.54 km2, and the reclamation is mainly concentrated in Zhejiang, Jiangsu and Liaoning, where the reclamation areas were all more than 1000 km2. According to the remote sensing images, there are three coastal reclamation hotspot regions including Bohai bay (in which is located Liaoning, Tianjin and Hebei), Jiangsu province coastal area and Hangzhou bay (in Zhejiang province). A large scale land reclamation plan of more than 5880 km2 has been made by local government and 2469 km2 has approved by the State Council. From the analyzed results, there is a significant collinearity between these indicators, and no significant correlation between the area of reclamation and selected indicators. Economic development and employees in marine industries have weak positive correlation and correspondingly, the area of cultivated land (ACL) had a negative correlation. Because of the weak correlation, there is an assumption that economic development, outcome of coastal reclamation and population growth were not only was the direct driving factor, but also the outcome of coastal reclamation and population growth was not the direct driving indicator. Construction land quota and huge economic returns to local government may be the direct driving factors according to our field investigation. To resolve the contradiction between the need for land and coastal wetland conservation, it is recommended that China should establish a special management agency and coordination mechanisms, reconsidered the implementation of the reclamation plans and projects that have been approved, enhance law enforcement and increase penalties and strengthen public participation in reclamation management.

Plastic debris has become one of the most serious issues in the marine environment, but little information is available on the occurrence of plastic debris in marine birds from China. In this study, one seabird species and two shorebird species were collected from Yongxing Island of South China Sea to investigate the accumulation of plastic debris. A total of 56 items of plastic debris were observed in 4 of 9 birds, with size ranging from 0.67 to 8.64 mm. Microplastics (5 mm, 52 items) accounted for 92.9% of the total items. The main color of plastic debris in marine birds was blue (91.1%), followed by dark (5.4%) and white (3.6%). The primary shape of plastic debris was thread (89.2%), followed by sheet (8.9%) and foam (1.8%). Plastic fragments were predominated by polypropylene-polyethylene copolymer (83.9%). This study highlighted that marine birds can mistake plastic debris as food items.

In this work, a matrix Riemann–Hilbert problem of a mixed Chen–Lee–Liu derivative nonlinear Schrodinger (CLL-NLS in brief) equation on the half-line is established by the unified transformation approach. The solution satisfying an initial–boundary value data of the CLL-NLS equation is reconstructed by solving the matrix Riemann–Hilbert problem. Especially, the spectral functions are not independent, but enjoy by a compatibility condition, which is the so-called global relation.

Aquaculture ponds are important anthropogenic sources of nitrous oxide (N2O). Direct N2O emissions arising from feed application to ponds have been widely investigated, but indirect emissions from N2O production from residual feeds in pond water are much less understood and characterized to refine the IPCC emission factor. In this study, we determined the concentrations and spatiotemporal variations of dissolved N2O and NO3--N in situ in three aquaculture ponds at the Min River Estuary in southeastern China during the culture period over two years, and calculated the indirect N2O emission factor (EF5) for aquaculture ponds using the N2O-N/NO3--N mass ratio methodology. Our results indicated that the EF5 values in the ponds over the culture period ranged between 0.0007 and 0.0543, with a clear seasonal pattern which closely followed that of the DOC:NO3-N ratio. We also observed significant spatial variations in EF5 among the three ponds, which could be attributed to the difference in feed conversion rate. In addition, we assessed the EF5 values from aquaculture ponds in five regions of the Chinese coastline across the latitudinal gradient from the tropical to the temperate zones. The average EF5 value from aquaculture ponds across the five coastal regions was 0.0093±0.0024, which was approximately 3.7 times of the IPCC default value for rivers and estuaries (0.0025). Moreover, the EF5 values demonstrated considerable spatial variations across these coastal regions with a coefficient of variation of 59%, which were largely related to the difference in water salinity. Our findings filled a key knowledge gap about the indirect N2O emission factor from aquaculture ponds, and provided field evidence for the refinement of EF5 value currently adopted by IPCC in the national greenhouse gas inventory.

The beach tourism resources of China are abundant with long coastline and many seawater bathing beaches. However, the natural quality of seawater bathing beach resources in China is uneven, and there are many differences in the degree of development, facilities, and management levels. The scientific evaluation of the quality of seawater bathing beach resources is conducive to fully understand the status of seawater bathing beach resources in China, so as to promote the rational development, sustainable utilization and scientific management of them. Giving different weight according to the type of beach, this study set up the quality evaluation system of the seawater bathing beaches resources in China from different perspectives of tourists, developers and managers by Beach Quality Index Model, and selected ten typical seawater bathing beaches in major areas for empirical research by extensive field investigation. According to the statistical data of 689 valid questionnaires and the results of field investigation and collected data, the comprehensive resource quality index of the ten typical seawater bathing beaches was calculated. The problems existing in the development and management of the main beaches in China and its’ countermeasures were analyzed. The results showed that there were three "Urban Beach”, five "Semi-urban/Semi-rural Beach” and two "Rural Beach”. The comprehensive resource quality level of the ten beaches was overall relatively high with one Excellent (Sanya Yalong), six Good (houshan Zhujiajian, Qinhuangdao Laohushi, Xiamen Gulangy, Qingdao Shilaoren, Beihai Yintan, Shenzhen Meisha, Weihai International seawater bathing beach) and two Medium (Dalian Jinshitan and Lianyungang Liandao). The method of first classifying and then giving different weights respectively can effectively solve the problem of “one size fits all” in the quality evaluation of various types of seawater bathing beach resources. Environmental problems, inadequate infrastructure and inadequate management services were the main problems, which need to be paid enough attention to.

Due to the urban industrial transformation and upgrading in China, the relationship between residential and employment spaces in large cities has changed significantly, resulting in an increasingly prominent job–housing separation phenomenon. Based on the taxi GPS trajectory data, this paper firstly analyzes the time and space distribution of job–housing–travel and the commuting characteristics of residents. Then, we construct the evaluation index systems of regional jobs–housing–taxi demand and regional social development level for Beijing. After calculating the weight of each index by using an entropy weight method, we analyze the coupling relationship between regional taxi demand and social development by building the coupling coordination degree model (CCDM). Conclusions are as follows: Firstly, it shows imbalance of space distribution of taxi orders in different administrative and functional areas. The order quantity gradually decreases from the main urban area to the edge, with the most in the living area, accounting for 46.23% of the total orders. Secondly, the daily variation trend of taxi orders in different functional areas is significantly different. During the morning rush hour, taxi orders flow out of residential areas and into office areas; however, during the evening rush hour, they flow out of the office and into the living area. For example, the residence area has a higher proportion of getting on passengers during the morning rush hour, which is 1.46 times that of the getting off ones. Thirdly, a low coupling coordination degree is observed between the regional social development level and the job–housing–taxi demand in Beijing, with a gradually decreasing from the main urban area to the outside, which is mainly caused by the imbalance between supply and demand. Therefore, it is suggested that the relevant government departments should formulate specific control schemes to traffic congestion according to local commuting features, and promote job–housing balance. Meanwhile, the taxi resources are supposed to be allocated reasonably by the striving to information symmetry, to promote the coordination and sustainability between the regional job–housing–taxi demand and social development level.

Under the background of greenhouse gases emission reduction, the measurement of carbon emissions from the tourism industry has attracted increasing academic attention. Tourism is not a traditional sector in the System of National Accounts, and as a result the statistics of carbon dioxide emissions of the tourism industry on a national scale is difficult to calculate. The measurement methodology of a bottom-up approach and a top-down approach were mainly used in others studies. Utilizing a boundary that includes domestic tourism consumption, inbound tourism consumption, and tourism consumption incurring domestically in relation to outbound travel and airfares paid to the national carriers, a top-down approach is used to measure the national tourism dioxide emissions combining the Tourism Satellite Account and the Input–Output model from productive industry. Using this case study, it was calculated that the total carbon emissions of the Chinese tourism industry in 2002, 2005, 2007 and 2010 were 111.49 Mt, 141.88 Mt, 169.76 Mt and 208.4 Mt respectively, accounting for 2.489%, 2.425%, 2.439% and 2.447% respectively of the total carbon emission of all industries in China. The indirect carbon emissions by other tourism sectors except the transport sector were 3–4 times their direct carbon emissions. Compared with the manufacturing industry, the tourism industry is an industry of low pollution and low energy consumption. We discuss the advantage and shortcoming of the two approaches and put forward some suggestions to assist the research of tourism carbon emissions.

Due to the constraints of freshwater for agricultural irrigation, sewage water has been used in farmland irrigation as an important supplement and alternative water resources during the past three decades in China, especially in northern areas. However, there is increasing concern about food safety and health risks, hence, a case study was undertaken to understand the long-term effect of sewage irrigation on heavy metal concentrations in soil and plants. Sewage sludge, soil and plant samples were collected and analyzed for heavy metals concentrations. Results showed that sewage irrigated soil contained much higher concentrations of Cd, Cu, Pb, Zn, Ni, Cr, As and Hg compared to clean water irrigated soil. The heavy metal content of the topsoil (0–20 cm) was much higher than that of the subsoil. Significant heavy metal (Cd, Zn and Hg) pollution has occurred in soils of areas that had been using untreated waste water irrigation in Tianjin, China. There were significant accumulations of heavy metals in wheat that used sewage irrigation. Compared with the other parts of the wheat plants, the higher contents of Cd, Cr, Pb and As in the roots indicated that roots had a strong absorption ability and maybe cause an obvious barrier effect. Based on the soil to plant transfer factor of heavy metals, there is a strong accumulation effect of Cd in vegetables. Overall, the concentrations of Cd, Pb, Ni, Cr and As were lower than the national permitted safety limits in soil. Mean Cd, Pb and As concentrations in vegetables were higher than the national safety limits, whereas the mean concentrations of Cu, Zn and Cr were below Chinese national safety limits. Therefore, in order to ensure food safety and use of sewage for irrigation, continuous monitoring and pollution control is needed.

To enhance the osteointegration and antibacterial property of titanium (Ti) implant, zinc calcium phosphate chemical conversion (Zn-Ca-PCC) was fabricated on pure Ti by phosphate chemical conversion technique. The surface of the coating was verified by combined techniques of scanning electron microscopy, energy-dispersive X-ray spectrometry, atomic force microscopy and water contact angle measurements. Plate-like Zn-Ca-PCC coatings are built up on the surface of Ti. The results obtained from the antibacterial studies suggest that the Zn-Ca-PCC coatings can greatly inhibit the growth of both Gram-positive ( Staphylococcus aureus ) and Gram-negative ( Pseudomonas aeruginosa ) bacteria. Moreover, the in vitro evaluations demonstrate that the adhesion, proliferation and differentiation of osteoblasts on Zn-Ca-PCC coatings were significantly enhanced compared with pure Ti. In conclusion, innovative Zn-Ca-PCC coatings on Ti with excellent antibacterial activity and biocompatibility are promising candidates for orthopedic and dental implants.

A novel bolaamphiphile surfactant N,N′-(octane-1,8-diyl)bis(pyrrolidine-2-carboxamide) (DAOP), was designed and synthesized from proline and 1,8-diaminooctane, as the hydrophilic part and hydrophobic part, respectively. After separation and purification, the structures of the synthesized bola surfactants were verified by IR, MS and 1H NMR. The pKa was measured by a titration experiment, the turbidity was determined using a Shimadzu UV-1750 spectrophotometer, and the critical micelle concentration (CMC) values of the synthesized surfactants in water were obtained using the conductivity and fluorescence probe measurements. The synthesized bolaamphiphile surfactants demonstrate the ability of self-assemble to form vesicles that were confirmed with dynamic light scattering and transmission electron microscopy. The results showed that the novel bolaamphiphile surfactant derived from proline might potentially be an excellent carrier for drug delivery.

Dissolved concentrations, saturation status, and emission fluxes of greenhouse gases (GHGs) in two reclamation mariculture ponds in the Bohai Gulf, China, were measured using the static headspace gas chromatography method and computed using a two-layer model of diffusive gas exchange. The study was conducted during August 2016 to assess diurnal variations in GHGs emissions. The main influencing factors of GHGs emissions from the ponds under the disturbance of artificial management were identified using Spearman correlation analyses and multiple stepwise regression analyses. Results showed that dissolved GHGs concentrations were stable throughout the day, whereas GHGs emission fluxes showed a clear diurnal variation with larger daytime values. The diurnal variation of N2O emission fluxes was greater than that of CO2 and that of CH4. Results also showed that pH of pond water was negatively correlated with CO2 and N2O emission fluxes and that air temperature was positively correlated with CH4 and N2O emission fluxes. In addition, ammonia (NH4+-N) was positively correlated with CH4 emission fluxes; water temperature and salinity were positively correlated with N2O emission fluxes. The estimated annual emissions from the reclamation aquaculture in Tianjin and the Bohai Rim region were 2.53 × 105 kg C–CO2, 6.94 × 103 kg C–CH4 and 1.11 × 103 kg N–N2O, and 3.42 × 107 kg C–CO2, 9.36 × 105 kg C–CH4 and 1.50 × 105 kg N–N2O respectively, indicating the important contribution of this fishery sector to GHGs emissions.

The fiber coupling efficiency of Gaussian-Schell model beams propagating through the oceanic turbulence of the Zernike tilt correction is studied. We derive the expression of the Zernike tilt corrected wave structure function. The numerical analysis reveals that a higher correction factor and spatial coherence of the laser beam increase the fiber coupling efficiency of the link. Our work shows that the increment of the fiber coupling efficiency caused by Zernike tilt correction under strong turbulence conditions is stronger than in the weak turbulence conditions, and the salinity fluctuation has a greater impact on it than temperature fluctuation does.

Solvents, accounting the majority of the organogel system, have a tremendous impact on the characteristics of gels. To date, there is a large variety of organogel systems; relatively few have been investigated in the field of structure-solvent correlation. Here, a series of solvent parameters were applied to explore the role of solvent effect on network forming and gel property, intending to build the connection between the precise solvent parameter and gel property. Among the solvent parameters, Kamlet–Taft Parameters and Hansen solubility parameters can distinguish specific types of intermolecular interactions, which could correlate solvent parameter with the gel property. From an analysis of the morphologies obtained from POM and SEM, the gelator structure has an impact on its self-assembly. For possible conformations, the gelators were investigated through XRD. The investigation of solvent-property relationship will provide a theoretical basis for controllable drug delivery implants.

Thermogels, used as multi-functional drug-loading materials, have properties that mainly rely on their gelator structure. Although a large variety of organogel systems are used as drug delivery carriers, relatively few have been investigated in terms of their structure-property correlations based on amino acid derivative gelators. Here, a series of amino acid based gelators were synthesized to explore the role of the gelator structure on functional properties, with the aim of establishing a connection between the molecular parameters and gel properties. By varying the three substitutions of the gelator backbone, it was found that a comprehensive interaction, consisting of hydrophobic forces, H-bonding interactions, conformational flexibility and steric repulsion, play a crucial role in determining the gelation properties. Hansen solubility parameters were employed to explore the solvent effect on the network forming and gel properties. From an analysis of the morphologies obtained from polarized optical microscope (POM), atomic force microscopic images (AFM) and scanning electron microscopy (SEM), the gelator structure was found to have an impact on the self-assembly. According to the X-ray diffraction (XRD), the possible conformations adopted by the gelators were revealed through molecular modelling. The ability to form intermolecular H-bonding is vital in molecular packing and, thus, gelation. A structure-property relationship was developed and proposed to provide a theoretical basis for controllable drug delivery implants.

The aims of this article were to investigate heavy metals concentrations in urban street dust of Tianjin, to examine spatial variations of heavy metals pollution, and to assess their health risk to local populations. Urban street dust samples were collected from 144 typical crossroads in an urban area of Tianjin. Levels of heavy metals were determined by atomic absorption spectrophotometer analyzer. Given comprehensive consideration of the complexity and uncertainty of health risk assessment, trapezoidal fuzzy number was introduced to assess the health risk of heavy metals in the urban street dust of Tianjin. The results showed that the pollution of heavy metals in the urban street dust of Tianjin was serious. The relatively serious metal pollution tended to be located in the center, north, northeast, and southeast of the study area. The research indicated that heavy metals in street dust had caused non-cancer hazard to children but had not caused non-cancer or cancer hazard to adults. The direct ...

This study aimed to determine sediment contamination in the Beidagang Wetland Nature Reserve to describe atmospheric deposition of trace metals. We analyzed Hg, Cd, Pb, TOC, TN, TP, δ13C, and δ15N, and studied their variations in surface sediments and in the vertical profiles of sediment cores collected from the reserve. Evaluation of environmental trace metal contamination using sediment quality guidelines and geochemical background values indicated that the risk of metal pollution in the reserve sediments was relatively low. Concentrations of Hg, Cd, and Pb in the sediments were much lower than concentrations in sediment samples from Bohai Bay and polluted rivers in Tianjin. Enrichment factors indicate that samples are moderately contaminated with Hg, Cd, and Pb; whereas the geo-accumulation index results classify the sediments as uncontaminated to moderately contaminated with Hg, Cd, and Pb. The distribution patterns of trace metal concentrations in the three core samples were uniform. δ13C and δ15N were used to track the sources of TOC and TN in sediments. Results show that TOC mainly originated from the residue and decaying matter of aquatic plants (e.g., algae, reeds, and Typha), while TN was derived from soil N and elevated atmospheric N deposition. Because domestic and industrial waste is not discharged into the Beidagang Wetland Nature Reserve, trace metals found in sediments mainly originate from atmospheric deposition. The results provide baseline data for analysis of trace metal accumulation in Beijing-Tianjin-Hebei, a region subject to atmospheric deposition in northern China.

We investigate the atmospheric turbulence effects on the propagation of vortex modes carried by Lommel beam. The analytic expression of the received signal and crosstalk mode intensity is derived based on the weak-to-strong non-Kolmogorov turbulence theory. The simulation results show that turbulence with small non-Kolmogorov spectrum parameter, small inner-scale factor and large outer-scale factor is more likely to induce modal crosstalk. With the increment of turbulence strength, the crosstalk spreads from adjacent modes to peripheral modes. The received signal intensity can be improved by use of Lommel beam with small asymmetry parameter, low orbital angular momentum quantum number and long wavelength. The results are helpful to the design of orbital angular momentum based free-space optical communication link.

In this paper, a new generalized $5\times5$ matrix spectral problem of Ablowitz-Kaup-Newell-Segur(AKNS) type associated with the enlarged matrix Lie super algebra is proposed and its corresponding super soliton hierarchy is established. The super variational identities is used to furnish super-Hamiltonian structures for the resulting super soliton hierarchy., 18 pages

Smooth cordgrass (Spartina alterniflora) was introduced to China in December 1979 to buffer against tides and to accelerate coastal wetland accretion. Since then, its propagation and natural dispersal have allowed this exotic plant to rapidly expand throughout coastal China with generally negative ecological effects. In 2003 S. alterniflora was labeled as an invasive plant in China, and it now covers ~50,000 ha. In this review, we first summarize the mechanisms of spread and spatial distribution of S. alterniflora, and how its physiological characteristics and strong adaptability to the available niche space in China's wetlands have enabled its spread and competition with native plants. Then we review the effects of S. alterniflora on ecosystem function in terms of habitat conversion and the alteration of biodiversity, soil carbon flux and sequestration, and various processes of nutrient regulation. We conclude that we need a long-term and context-dependent perspective, in order to maximize the benefits and minimize the costs of S. alterniflora within each of China's unique provinces.

With the rapid development of the urban economy and transportation, the taxi market has presented a series of problems regarding unreasonable resource allocation, demand–supply imbalance, and driver income imbalance. Since the distribution of high-quality customers (hereafter HQC) affects drivers’ incomes and resource allocation in the taxi market, it is of great significance to study the HQC distribution to address these imbalance problems and understand the imbalance of the taxi market. In this paper, we calculate the profit margin of each order and construct a high-quality customer evaluation model from taxi GPS trajectory data. In analyzing the spatial–temporal distribution of HQC, our results indicate that HQC present a regional aggregation phenomenon in the spatial dimension, and HQC are mainly distributed in the main urban areas. The distribution of HQC is imbalanced in various administrative districts and functional zones. The daily change of orders in each administrative district is the same, but the temporal distribution of HQC is imbalanced. The temporal distribution of HQC in each functional zone is imbalanced, showing different daily change trend. According to these results, we suggest that the pricing of taxis and online ride-hailing services be coordinated based on the spatial–temporal distribution characteristics of HQC and that resources be rationally allocated to promote the sustainable and healthy development of urban transportation.

With the development of social economy, a series of problems such as an imbalance of supply and demand, unreasonable resource allocation and low operation efficiency appear in the urban taxi market. Based on the GPS trajectory data of taxis, this paper calculates and analyzes the operation efficiency of taxis in terms of time and space dimensions in Chengdu, Sichuan Province by using the capacity utilization rate. The results show that, firstly, the weekly variation trend of taxi capacity utilization rate is obviously periodic and its daily variation trend is unbalanced, which is reflected in the morning peak, afternoon peak, evening peak and night peak. The daily variation trend of taxi capacity utilization rate is significantly different between workdays and weekends, and the capacity utilization rate on weekends is much lower. Secondly, there is a spatial imbalance in the distribution of taxi capacity utilization rate. The capacity utilization rate of the main urban district is relatively high, and that of the other urban districts negatively correlates with the economic level and population density. The supply and demand of taxis are balanced within the various functional zones but unbalanced between different functional zones. It is suggested that the relevant departments shall reasonably allocate taxi resources according to the imbalance of taxi capacity utilization rate in time and space to improve the overall operation efficiency, and integrate market mechanism with government regulations to promote the sustainable development of urban taxis.

We propose a model of the fiber coupling efficiency for a partially coherent collimating laser beam propagating through turbulent biological tissue to fiber. By studying the influence of link parameters on fiber coupling efficiency, we find that there are optimal focal length and transmitting beam radius for specific turbulent tissue. We also find that a larger characteristic length and small length-scale factor, or smaller fractal dimension and strength coefficient of refractive-index fluctuation will lead to larger fiber coupling efficiency. In order to improve the fiber coupling efficiency, we recommend select the optimum focal length, moderate transmitting beam radius, lower aperture diameter of the coupling lens, longer wavelength and higher coherent degree of light source. 2000 MSC: 41A05, 41A10, 65D05, Keywords: Fiber coupling efficiency, Biological tissue, Turbulence, Optimum parameter, Laser beam

The in vitro degradation behavior of organogel with different gelators based on amino acid was investigated in detail. Two methods were applied in this research: weighting method and high-performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD) method, which was established for the first time. Their degradation behaviors in vivo were investigated by varying the kind and concentration of gelators via subcutaneous implantation. The results showed that the stronger the gelation ability or the higher the gelator concentration, the slower the degradation rate of organogel. Moreover, the organogel prepared by oils with longer alkyl length degraded slower than that of the shorter ones, which also decreased in thermal stability and mechanical strength. The investigation on degradation process showed that the degradation rate was mainly controlled by the collapse of network structure formed by gelators. In conclusion, organogel had a tunable degradation rate through altering the gelator type, oil type and the gelator concentration. It remains a promising candidate for subcutaneous in-situ implant as drug delivery vehicle.

The fiber coupling efficiency between the turbulent ocean to fiber of a partially coherent Gaussian beam propagating through the weak to strong anisotropic oceanic turbulence is studied. We derive the expression of new model of the fiber coupling efficiency for the partially coherent Gaussian beam. The numerical analyses reveal that larger inner scale and anisotropic factor, weaker oceanic turbulence strength, and smaller temperature-salinity contribution ratio will lead to a higher coupling efficiency; a longer wavelength, an suitable aperture diameter of the coupling lens, an optimum focal length and beam size, and a higher coherent degree will improve the fiber coupling efficiency. Our fiber coupling efficiency is higher than the previous fiber coupling efficiency.