Spatial distribution, ecological risk, and human health assessment of heavy metals in lake surface sections - a case study of Qinghai Lake, China.

Qinghai Lake is the largest inland saltwater lake in China, with a drainage area of 29,661 km2. This study sought to conduct an ecological and human health risk assessment of metals and heavy metals, including copper, as well as investigate their concentration, distribution, and source distribution. In terms of seasonal variation, the increases in Fe, Cr, As, Pb, and Hg were relatively large, and the spatial distribution of metals presented a three-level stepped distribution trend, gradually increasing from east to west. By further exploring the source and migration path of pollutants, our study found that the source of metals in the sediments of Qinghai Lake is mainly controlled by five rivers entering the lake. Enrichment factor (EF) calculations indicated that the metal accumulation or enrichment capacity of the three central points in Qinghai Lake Basin was strong. Interestingly, the enrichment capacity of Cu and Zn was the strongest among all metals but occurred at low and medium concentration levels, respectively. The Igeo and [Formula: see text] ecological risk assessment results indicated that the individual metals posed little to no ecological risks to the Qinghai Lake Basin. However, the multi-element environmental risk comprehensive index (RI) indicated that Hg (RI = 147.97) represented a slight ecological hazard, Mn (RI = 181.13) posed moderate ecological hazards, and Zn (RI = 386.66) posed strong ecological hazards. The human health risk assessment results showed that the heavy metals in the surface sediments of Qinghai Lake currently do not pose a threat to human health. This information may facilitate the implementation of more stringent monitoring programs in the aquatic ecosystem by the relevant regulatory authorities.

Adsorption and desorption of heavy metals at water sediment interface based on bayesian model.

Estuarine areas are not only the main gathering point for human sewage but also the place where one-way and two-way fluids interact, thus forming a complex and changeable geochemical physical field. Here, heavy metals (HMs) are adsorbed and desorbed due to physical, chemical, and biochemical processes. However, the adsorption and desorption behavior of HMs in the aquatic environment is complex, and physicochemical processes occurring in the estuarine sediment-water interface control the direction and boundaries of the system. This study analyzed the migration and distribution of HMs in rivers and lakes, and established a Bayesian network model to quantitatively understand the impact of nutrients and key environmental factors on the adsorption-desorption behavior of HMs in lake and estuaries, as well as the competitive relationship between environmental factors. The influence of environmental factors and the occurrence of HMs are both important model inputs. Our findings indicated that the migration risk of Cd in Qinghai Lake was high. Environmental factors such as Cation exchange capacity (CEC), Organic matter (OM), Soluble fluoride (SFL), and pH play the most important role in the adsorption and desorption of HMs. Our findings also indicated that the exchange and activity of HMs in sediments were much higher than in the overlying water. The organic matter content was the most complex environmental factor affecting HMS adsorption and desorption at the water-sediment interface. Additionally, the mass concentration of dissolved oxygen (DO) has a linear relationship with bioavailable HMs in river and lake sediments, but has no linear relationship with the concentration of water-soluble HMs. Interestingly, there are synergistic effects between environmental factors, which directly or indirectly affect the release of bioavailable HMs. However, it is important to determine whether the effects of different environmental factors on the exchange of bioavailable HMs are negative or positive. Our findings suggested that Bayesian network (BN) signals (positive or negative) could provide insights into the transfer direction of metals in the water-sediment interface.

Dual risk-aversion programming for regional industrial structure adjustment with water-energy nexus: A case study of Tianjin, China.

The water-energy nexus (WEN) system is a large-scale complex system that comes with diverse forms of risks owing to many challenges in the process of maintaining economic-resource-environmental sustainability. First, the rapidly increasing demand for water and energy subjects many regions to the high risk of water and energy shortages. Second, decision makers face difficulties in weighing system benefits and loss risks under a series of stricter water-energy policies. To handle the aforementioned dual risks of WEN, in this study we propose copula-based stochastic downside risk-aversion programming (CSDP) for regional water-energy management. CSDP integrates the superiority of the copula analysis method and downside risk-aversion programming into a framework, which can not only reveal the risk interactions between water resources and energy demand by using copula functions under different probability distributions, even previously unknown correlations, but also control economic risk, tackle systemic uncertainties, and provide an effective linkage between system stability and conflicting economic benefits. The proposed model was applied to a water-energy system case study in Tianjin City, China. Optimal solutions for various water resources and energy demand copulas associated with different scenarios and hierarchical risk levels were examined in the CSDP model. The results showed that water resources have a greater influence than energy on industrial structure adjustment in Tianjin, with consequent effects on system benefits, optimal output value schemes, and environmental protection strategies. In addition, the tertiary industry provides a new opportunity for economic growth based on a large amount of water-energy consumption, and its potential resources and water-air pollution risks also deserve extensive attention.

A coupling simulation and optimization method developed for environmental-economic management of Lake watershed.

Many lake basins are facing the challenge of mitigating water shortage and water pollution while maintaining economic growth. Existing planning method for water pollution control often focus on how to alleviate water pollution effectively at the lowest cost, but rarely pay attention to the dynamic feedback and synergy effects between water pollution abatement, water conservation and social economy. This article proposes a method which consists of system dynamics model (SDM), Soil and Water Assessment Tool (SWAT) and objective programming model (OPM). It could be used to create insights on basin-wide water problems from a systematic perspective. The case study on Yilong Lake Watershed evaluates the proposed measures in existing local planning, calculates the optimal scheme, and discusses issues including the uncertainty of effectiveness, choice between recycling sewage and transferring outside, and the necessity of restricting food processing industry. This method could be improved on the simulation of social and industrial economy, the simulation of water cycle, and the spatial planning.

Study on Automatic Multi-Classification of Spine Based on Deep Learning and Postoperative Infection Screening.

The preoperative qualitative and hierarchical diagnosis of intervertebral foramen stenosis is very important for clinicians to explore the effect of multimodal analgesia nursing on pain control after spinal fusion and to formulate treatment strategies and patients' health recovery. However, there are still many problems in this aspect, and there is a lack of relevant research and effective methods to assist clinicians in diagnosis. Therefore, to improve the accuracy of computer-aided diagnosis of intervertebral foramen stenosis and the work efficiency of doctors, a deep learning automatic grading algorithm of intervertebral foramen stenosis image is proposed in this study. The image of intervertebral foramen was extracted from the MRI image of sagittal spine, and the image was preprocessed. 86 patients with spinal fusion treated in our hospital, specifically from May 2018 to May 2020, were randomly divided into the control group (routine analgesic nursing) and the multimodal group (multimodal analgesic nursing), with 43 cases in each group. The pain control effect and satisfaction of the two groups were observed. The results after multimodal analgesia nursing show that the VASs of the multimodal group at different time points were significantly lower than those of the control group (P < 0.05); the satisfaction score of pain control in the multimodal group was significantly higher than that in the control group (P < 0.05). Multimodal analgesia nursing for patients undergoing spinal fusion can effectively reduce the degree of postoperative pain and improve the effect of pain control and satisfaction with pain control, which is worthy of promotion.

Comparison of concurrent chemoradiotherapy with radiotherapy alone for locally advanced esophageal squamous cell cancer in elderly patients: A randomized, multicenter, phase II clinical trial.

This randomized, multicenter, phase II clinical trial was performed to compare the safety and efficacy of concurrent chemoradiotherapy using S-1 (CCRT) with radiotherapy alone (RT) for elderly patients with locally advanced esophageal squamous cell carcinoma (ESCC). All eligible patients were randomly assigned to the CCRT group or the RT group at a 1:1 ratio. The CCRT group received 50.4 Gy radiotherapy concurrent with S-1 and the RT group received 59.4 Gy radiotherapy alone. The primary endpoints were toxicity and the overall response rate (ORR), and the secondary endpoints were overall survival (OS) and progression-free survival (PFS). In total, 157 elderly patients with ESCC were recruited from December 2016 to March 2020. By June 2021, the median follow-up duration had reached 38 months. No grade 5 toxicities occurred in either group and the overall rate of severe toxicities (≥grade 3) was higher in the CCRT group (19.2% vs 7.6%; P = .037), particularly neutropenia (7.7% vs 1.3%; P = .06). The CCRT group presented a significantly higher ORR (83.3% vs 68.4%; P = .009) and prolonged PFS (25.7 vs 13.9 months; P = .026) than the RT group. The median OS was 27.3 months in the CCRT group and 19.1 months in the RT group (P = .59). For patients older than 70 years with locally advanced ESCC, concurrent chemoradiotherapy with S-1 had tolerable adverse effects and improved ORR and PFS compared to radiotherapy alone.

Response Prediction to Concurrent Chemoradiotherapy in Esophageal Squamous Cell Carcinoma Using Delta-Radiomics Based on Sequential Whole-Tumor ADC Map.

Purpose: The purpose of this study was to investigate the association between the radiomics features (RFs) extracted from a whole-tumor ADC map during the early treatment course and response to concurrent chemoradiotherapy (cCRT) in patients with esophageal squamous cell carcinoma (ESCC). Methods: Patients with ESCC who received concurrent chemoradiotherapy were enrolled in two hospitals. Whole-tumor ADC values and RFs were extracted from sequential ADC maps before treatment, after the 5th radiation, and after the 10th radiation, and the changes of ADC values and RFs were calculated as the relative difference between different time points. RFs were selected and further imported to a support vector machine classifier for building a radiomics signature. Radiomics signatures were obtained from both RFs extracted from pretreatment images and three sets of delta-RFs. Prediction models for different responders based on clinical characteristics and radiomics signatures were built up with logistic regression. Results: Patients (n=76) from hospital 1 were randomly assigned to training (n=53) and internal testing set (n=23) in a ratio of 7 to 3. In addition, to further test the performance of the model, data from another institute (n=17) were assigned to the external testing set. Neither ADC values nor delta-ADC values were correlated with treatment response in the three sets. It showed a predictive effect to treatment response that the AUC values of the radiomics signature built from delta-RFs over the first 2 weeks were 0.824, 0.744, and 0.742 in the training, the internal testing, and the external testing set, respectively. Compared with the evaluated response, the performance of response prediction in the internal testing set was acceptable (p = 0.048). Conclusions: The ADC map-based delta-RFs during the early course of treatment were effective to predict the response to cCRT in patients with ESCC.

ABCAttack: A Gradient-Free Optimization Black-Box Attack for Fooling Deep Image Classifiers.

The vulnerability of deep neural network (DNN)-based systems makes them susceptible to adversarial perturbation and may cause classification task failure. In this work, we propose an adversarial attack model using the Artificial Bee Colony (ABC) algorithm to generate adversarial samples without the need for a further gradient evaluation and training of the substitute model, which can further improve the chance of task failure caused by adversarial perturbation. In untargeted attacks, the proposed method obtained 100%, 98.6%, and 90.00% success rates on the MNIST, CIFAR-10 and ImageNet datasets, respectively. The experimental results show that the proposed ABCAttack can not only obtain a high attack success rate with fewer queries in the black-box setting, but also break some existing defenses to a large extent, and is not limited by model structure or size, which provides further research directions for deep learning evasion attacks and defenses.

Dynamic metabolism network simulation for energy-water nexus analysis: A case study of Liaoning Province, China.

Faced with gradually serious energy and water crisis, the exploration of energy-water nexus metabolism relationships could provide a new direction for achieving the resources conservation and consumption reduction. In this paper, a comprehensive assessment for energy-water metabolic network is proposed to search the dynamic evolution and quantify the sectoral metabolic processes in Liaoning Province, China. Input-output analysis (IOA) and ecological network analysis (ENA) are integrated to clarify the embodied linkages and the complicated system interactions in the energy-water nexus network. The coefficients of "water-related energy" and "energy-related water" are explored through the system dynamics model (SDM) based on the consecutive input-output tables from 2012 to 2018. In addition, energy-water nexus efficiency index (EWEI) is constructed to evaluate the metabolism circulation efficiency of energy-water nexus network. The results indicate that (a) the energy and water outflow sectors mainly concentrate in primary industries and tertiary industries, while inflow sectors mainly concentrate in secondary industries; (b) the sectoral relationship provides effective pathways to implement collaborative resource saving and efficiency improvement measures, and the key sectors with the highest correlation with other sectors in energy-water nexus are AGR (agriculture), MIN (mining) and WRC (wholesale, retail and catering services). (c) the EWEI shows a gradually downward trend and the state of the energy system would determine the health of the energy-water nexus metabolism more strongly than water system.

MassARRAY multigene screening combined with LDL-C and sdLDL-C detection for more favorable outcomes in type 2 diabetes mellitus therapy.

BACKGROUND: To determine the clinical value of multigene polymorphisms, LDL-C and sdLDL-C on T2DM therapy. METHODS: In total, 352 T2DM patients before and after treatment and 48 healthy individuals were enrolled in this study. LDL-C and sdLDL-C were detected in 352 T2DM patients and 48 healthy individuals by Quantimetrix Lipoprint System. The 11 gene polymorphisms-HTR3B (rs2276307, A > G), APOE (rs7412, c.526C > T), APOE (rs429358, c.388 T > C), CYP2C9*3 (rs1057910, c.1075A > C), KIF6 (rs20455, c.2155 T > C), HMGCR (rs17238540, T > G), HMGCR (rs17244841, A > T), ABCB1 (rs2032582, A > C/T), HTR7 (rs1935349, C > T), SLCO1B1 (rs4149056, c.521 T > C), and CETP (rs708272, G > A)-were screened in these 352 T2DM patients by the Agena Bioscience MassARRAY system before therapy. RESULTS: Genetic polymorphisms associated with T2DM and statin effects in pretreatment patients were detected, then results showed that all 11 genes had heterozygous mutation, and 7 genes had homozygous mutation in 352 T2DM patients, more specifically reflected that these gene polymorphisms were common in Chinese T2DM patients. LDL-C and sdLDL-C were detected before and after treatment, sdLDL mainly existed in T2DM patients, and T2DM patients had higher mean levels of sdLDL-C than healthy people. After pharmacotherapy, the coincidence rates of decreases in LDL-C and sdLDL-C levels were 88.35% (311/352) and 84.09% (296/352), consistent with patients in remission. CONCLUSIONS: Gene polymorphisms related to pharmacotherapy were common in Chinese T2DM patients. And the expression of LDL-C and sdLDL-C was consistent with the T2DM disease course. Combined multigene screening before therapy and LDL-C and sdLDL-C detection before and after therapy could better assist T2DM treatment.

Plateau river research: spatial-temporal variations of δ18O and δd in the water of the Yarlung Tsangpo River and their controlling factors.

Stable isotope technology has been widely used to trace sources and evolution of water bodies, relationships between different water bodies and pollution sources. Based on δ18O and δD data from the Yarlung Tsangpo River in 2017, this paper analyzes the composition characteristics of δ18O and δD in the river water during the low-flow, high-flow and normal-flow seasons of the entire Yarlung Tsangpo River and further reveals the spatial evolution and influencing factors. The results show that the values of δ18O, δD and d-excess were different in time and space. The δ18O, δD and d-excess values of the Yarlung Tsangpo River in the low-flow season were significantly higher than in the high-flow season. This was mainly due to weak evaporation enrichment and precipitation supply effects on the river water during the wet season. From the perspective of season change, the d-excess in the low-season is significantly higher than in the high-flow season and the normal-flow season; from the perspective of spatial change, the d-excess shows the same spatial variation trend as the δ18O, which first decreases and then increases. Based on the investigation of δ18O and δD in the main and Branch rivers of the Yarlung Tsangpo River Basin, it was found that the upper reaches of the basin were mainly supplied by snowmelt, the lower reaches were mainly supplied by rainfall.

Evaluation of Influencing Factors in Tetravalent Uranium Complex-Mediated CO2 Functionalization by Density Functional Theory.

The functionalization of CO2 mediated by a series of U(IV) mixed-sandwich compounds, (COTTIPS2)Cp*UR (R = -CH3, -CH2Ph, -CH2TMS, -CH(TMS)2, -NHPh, -OPh, -SPh, -SePh; COTTIPS2 = C8H6(SiiPr3-1,4)2; Cp* = C5Me5; TMS = SiMe3), was investigated by the density functional theory method. A two-step mechanism was revealed, in which the insertion of CO2 into the U-C bond was identified as the rate-determining step via a transition state featured by a four-membered ring with a free-energy barrier of 18.8 kcal/mol to the reaction of the (COTTIPS2)Cp*UCH3 system. The whole reaction was strongly exothermic by 45.0 kcal/mol. Substitution effect was discussed, including the bulkiness of the R group and the nature of the ligating atom, and steric hindrance and electrostatic interactions were found to be responsible for the observed variation in reactivity. The reactivity of U(III) and U(IV) complexes in CO2 functionalization was also compared and discussed. The results were consistent with experimental studies and complemented with molecular level of understanding on the mechanisms of CO2 functionalization promoted by tetravalent U complexes.

Enhance embedding capacity for switch map based multi-group EMD data hiding.

Exploiting Modification Direction (EMD) based data hiding achieves good stego-image quality and high security level. Recently, a section-wise EMD was proposed to enhance the embedding capacity of EMD. Later, Wang et al. introduced a switch map based multi-group EMD to further improve the embedding capacity. However, by a detail observation on the switch map in Wang et al.'s scheme, we find that more codewords with longer code-length can be put into the switch map. In this paper, we build a new switch map by Huffman code, and construct an enhanced multi-group EMD using Huffman code based switch map. Our scheme has higher embedding capacity than Wang et al.'s scheme and other EMD based data hiding methods.

Reducing file size and time complexity in secret sharing based document protection.

Recently, Tu and Hsu proposed a secret sharing based document protecting scheme. In their scheme, a document is encrypted into n shares using Shamir's (k,n) secret sharing, where the n shares are tied in with a cover document. The document reconstruction can be accomplished by acknowledgement of any k shares and the cover document. In this work, we construct a new document protecting scheme which is extended from Tu-Hsu's work. In Tu-Hsu's approach, each inner code of secret document takes one byte length, and shares are generated from all inner codes with the computation in GF(257), where 257 is a Fermat Prime that satisfies 257 = 223+ 1. However, the share size expands when it equals to 255 or 256. In our scheme, each two inner codes of document is combined into one double-bytes inner code, and shares are generated from these combined inner codes with the computation in GF(65537) instead, where 65537 is also a Fermat Prime that satisfies 65537 = 2 24+ 1. Using this approach, the share size in our scheme can be reduced from Tu-Hsu's scheme. In addition, since the number of combined inner codes is half of the inner codes number in Tu-Hsu's scheme, our scheme is capable of saving almost half running time for share generation and document reconstruction from Tu-Hsu's scheme.

Nattokinase Crude Extract Inhibits Hepatocellular Carcinoma Growth in Mice.

Nattokinase (NK, E.C. 3.4.21.62) is a serine protease produced by Bacillus subtilis natto that shows promise for the treatment of thrombotic disease. In this study, we assessed the effects of NK on the development of hepatocellular carcinoma (HCC), a principal malignancy of the liver that causes morbidity and mortality worldwide. Crude extracts of NK (NCE) were isolated from fermentation medium by centrifugation and separated into three fractions (<10 K, 100~30 K and >30K). Orthotopic HCC mouse models were established and NCE was administered by oral gavage. H&E staining was performed to examine the pathology of HCC livers. Immunohistochemistry and immunofluorescence were used to evaluate FOXM1, CD31, CD44 and vimentin expression in the liver. Compared to PBS groups, NCE increased the survival rates of HCC-bearing mice to 31% and decreased ascites. Low-intensity ultrasound imaging showed that the hypoechoic mass area was lower in NCE-treated mice and that tumor growth significantly decreased. IHC staining showed that the expression of FOXM1 was inhibited by NCE treatment. Immunofluorescence results revealed lower levels of CD31, CD44 and vimentin in the NCE groups. Taken together, these data demonstrate that NCE from Bacillus subtilis natto improves survival and inhibits tumor growth in HCC mice.

Computational Comparative Mechanistic Study of C-E (E=C,N,O,S) Coupling Reactions through CO2 Activation Mediated by Uranium(III) Complexes.

A DFT mechanistic study is undertaken on the functionalization of CO2 to form C-C, C-N, C-S, and C-O bonds promoted by trivalent uranium complexes (Tp*)2 UR [Tp*=hydrotris(3,5-dimethylpyrazolyl)-borate ligand, R= -C≡CPh (Cpda-CC), -C≡CSiMe3 (Cpda-CSi), -NHPh (Cpda-N), -SPh (Cpda-S), and -OPh (Cpda-O)]. These model systems are similar in view of their two-step reaction mechanisms, that is, the insertion of CO2 into the U-E (E=C, N, O, S) bond to form a [U-κ1 -O2 C] intermediate, followed by the reorientation of the carboxylate group to coordinate with the U atom in the κ2 manner (Cpdb-X, X=CC, CSi, N, S, O). However, the free energy barriers to the rate-determining steps are substantially different, increasing in the order Cpda-S

A multi-walled silk fibroin/silk sericin nerve conduit coated with poly(lactic-co-glycolic acid) sheath for peripheral nerve regeneration.

The linearly oriented multi-walled silk fibroin/silk sericin (SF/SS) nerve conduits (NCs) can provide physical cues similar to native peripheral nerve fasciculi, but the mechanical properties of which are not excellent enough. In this study, NCs with a novel and bionic design with dual structures were developed. The important features of our NCs is that the internal skeleton (the multi-walled SF/SS conduits) has a bionic structure similar to the architecture of native peripheral nerve fasciculi, which is beneficial for nerve regeneration, and the outer sheath (the hollow poly(lactic-co-glycolic acid) [PLGA] conduits) could provide strong mechanical protection for the internal skeleton. The linearly oriented multi-walled SF/SS conduit was fabricated and inserted in the hollow PLGA sheath lumen and then used for the bridge across the sciatic nerve defect in rats. The outcome of the peripheral nerve repair post implantation was evaluated. The functional and morphological parameters were examined and showed that the novel PLGA-coated SF/SS NCs could promote peripheral nerve regeneration, approaching those elicited by nerve autografts that are the first candidate for repair of peripheral nerve defects. Thus, these updated NCs have potential usefulness to enhance functional recovery after repair of peripheral nerve defect.