Migration and risks of potentially toxic elements from sewage sludge applied to acid forest soil

`The application of sewage sludge(SS)to forested lands may lead to the downward migration of potentially toxic elements(PTEs)through rainfall and thus pose risk to the subsoil and groundwater.Batch column experiments were conducted using leaching water equivalent to the rainfall amount in the study area over 3 years to investigate changes in concentrations of PTEs,including copper(Cu),zinc(Zn),lead(Pb),cadmium(Cd),and nickel(Ni)in the leachate from the acidic forest soil.Water quality index of leachate,potential ecological risk and human health risk in soil at different leaching stages were compared.Sewage sludge was applied at SS/soil mass ratios of 0:100(controls),15:85(T1),30:70(T2),45:55(T3),60:40(T4),and 75:25(T5).All treatments resulted in increased PTEs concentration in the upper 20 cm soil,T3-T5 increased potential ecological risk from"low"(control)to"moderate"or"considerable".During first year leaching,PTEs concentration increased with increasing SS/soil ratios,but the water quality index of T1-T3 was"excellent"or"good".Pb,Cu,Cd,and Ni in the 20-40 cm soil depth,and Zn in the 60-80 cm soil depth were also enriched,but potential ecological risk was"low".In subsequent leaching,PTEs concentration of leachate gradually returned to the background value and water quality index was"excellent".There were no significant changes in PTEs and ecological risk observed.During the monitoring process,the health risk caused by the migration of PTEs to the human body was always within the acceptable range.Overall,this study provides a reference for the management of risks from the application of SS on forestlands,i.e.,SS/soil ratios<45:55 is recommended on forestlands,and special attention should be given to early leaching risk.In addition,it also provides an important assessment method for the risk of PTEs leaching and migration in forested land application.

The effects of dietary fiber level on nutrient digestibility in growing pigs

The objective of this study was to investigate the effects of total dietary fiber level on nutrient digestibility and the relationship between apparent total tract digestibility of total dietary fiber, and soluble dietary fiber, insoluble dietary fiber and available energy. Sugar beet pulp was as the only fiber source. The experiment was designed as a 6 x 6 Latin square with an adaptation period of 7 d followed by a 5-d total collection of feces and urine. Feed intake tended to decrease （P =0.] O） as total dietary fiber level increased. The apparent total tract digestibility of dry matter, crude protein and gross energy decreased （P 〈0.0]） when total dietary fiber increased but the digestibility of soluble dietary fiber and insoluble dietary fiber increased （P 〈0.01）. The digestible energy and metabolizable energy content of diets decreased （P 〈0.01） as the total dietary fiber increased.

Sustained delivery of vascular endothelial growth factor mediated by bioactive methacrylic anhydride hydrogel accelerates peripheral nerve regeneration after crush injury

Neurotrophic factors,currently administered orally or by intravenous drip or intramuscular injection,are the main method for the treatment of peripheral nerve crush injury.However,the low effective drug concentration arriving at the injury site results in unsatisfactory outcomes.Therefore,there is an urgent need for a treatment method that can increase the effective drug concentration in the injured area.In this study,we first fabricated a gelatin modified by methacrylic anhydride hydrogel and loaded it with vascular endothelial growth factor that allowed the controlled release of the neurotrophic factor.This modified gelatin exhibited good physical and chemical properties,biocompatibility and supported the adhesion and proliferation of RSC96 cells and human umbilical vein endothelial cells.When injected into the epineurium of crushed nerves,the composite hydrogel in the rat sciatic nerve crush injury model promoted nerve regeneration,functional recovery and vascularization.The results showed that the modified gelatin gave sustained delivery of vascular endothelial growth factors and accelerated the repair of crushed peripheral nerves.

Analysis of ethoxyquin and its oxidation products in swine tissues by gas chromatography-tandem mass spectrometry for evaluating the feed-toanimal tissue transfer of ethoxyquin and its metabolites

Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI)and ethoxyquin dimer(EQDM)in animal tissue.Thus,it would pose potential health hazards to consumers.However,the method for the simultaneous determination of EQ,EQI and EQDM in animal tissues is currently not available,and the accumulation extend of these chemicals in animal tissues after EQ administration remains to be evaluated.Results:A gas chromatography-tandem mass spectrometry method was successfully developed for the simultaneous determination of EQ,EQI and EQDM in swine tissues.The quantitative limits of EQ,EQI and EQDM can achieve to 0.5,5.0 and 5.0μg/kg in swine tissues,respectively.The spiked-recovery ratios of the three analytes(5–2000μg/kg)were in the range of 64.7%–100.7%with relative standard deviations below 11.6%.Moreover,the utilization of this method for the analysis of actual swine tissue samples revealed that the application of commercial EQ additive in swine diet would produce the residues of all the three chemicals(EQ,EQI and EQDM)in fat,kidney,liver and muscle.Conclusions:The assay accuracy and precision of this GC-MS/MS method can meet the requirement of quantitative analysis.Meanwhile,the safety of EQ as a feed additive should be seriously considered with regard to food safety concerns since the oxidation product of EQ may have potential carcinogenicity.

A MPTCP Scheduler for Web Transfer

Multipath TCP(MPTCP)is the most significant extension of TCP that enables transmission via multiple paths concurrently to improve the resource usage and throughput of long flows.However,due to the concurrent multiple transfer(CMT)in short flow trans-mission,the congestion window(cwnd)of each MPTCP subflow is too small and it may lead to timeout when a single lost packet cannot be recovered through fast retransmission.As a result,MPTCP has even worse performance for short flows compared to regular TCP.In this paper,we take the first step to analyze the main reason why MPTCP has the diminished performance for short flows,and then we propose M PTCP-SF,which dynamically adjusts the number of subflows for each flow.In particular,MP TCP-SF firstly analyzes the distribution characteristics of the web objects to extract two thresholds to be used for classifying each flow.After eceiving each new ACK,M PTCP-SF periodically counts the data being sent based on per-flow and uses the threshold to classify the we blows.Finally,MPTCP-SF dynamically switches path scheduling model for different classification flows.We conduct extensive experiments in NS3 to evaluate its efficiency.Our evaluation proves that MPTCP-SF decreases the completion time of short flows by over 42.64% com-pared to MPTCP,and the throughput achieved by MPTCP-SF in transmitting long flows is about 11.11%higher than that of MPTCP in a WLAN/LTE wireless network.The results successfully validate the improved performance of MPTCP-SF.

Use of near-infrared reflectance spectroscopy for the rapid determination of the digestible energy and metabolizable energy content of corn fed to growing pigs

Background： The ability of near-infrared reflectance spectroscopy（NIRS） to determine the digestible energy（DE）and metabolizable energy（ME） content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set（n = 88） and a validation set（n = 29）. The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez（J Anim Sci. 71：3389–98,1993）. The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square（MPLS） regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results： The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration（RSQcal）, cross-validation（R^2CV）, and validation（RSQv） were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQcal, R^2CV, and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME（RPD_v= 2.38, 〈 2.50）, the other three equations built from actually determined energy and calculated DE produced good prediction performance（RPD_vranging from 2.53 to 2.69, 〉 2.50） when applied to validation samples.Conclusion： These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.

Stability analysis of Alfvén eigenmodes in China Fusion Engineering Test Reactor fully non-inductive and hybrid mode scenarios

In this paper, NOVA/NOVA-K codes are used to investigate the stability of Alfvén eigenmodes(AEs) in the China Fusion Engineering Test Reactor(CFETR). Firstly, the stability of AEs excited by energetic alpha particles is investigated. For the fully non-inductive scenario, it is found that all AEs are stable, and the least stable toroidal mode number is n= 8. However, for the hybrid mode scenario, it is found that many AEs are unstable, and the least stable toroidal mode numbers are n= 7, 8. Secondly, the effect of energetic alpha-particle parameters and beam ions on AE stability is also presented. The threshold of the least stable AE is about βcrit,α = 1.12%,crit,less than the value of alpha-particle beta(βα=1.34%). The result demonstrates that the AEs excited by alpha particles are weakly unstable. The effect of the beam ions on AE stability is found to be very weak in CFETR.

Differential DNA methylation profiles of human B lymphocytes and Epstein-Barr virus-immortalized B lymphocytes

Objective： This study aimed to comprehensively assess Epstein-Barr virus（EBV）-induced methylation alterations of B cell across whole genome.Methods： We compared DNA methylation patterns of primary B cells and corresponding lymphoblastoid cell lines（LCLs） from eight participants. The genome-wide DNA methylation profiles were compared at over 850,000 genome-wide methylation sites.Results： DNA methylation analysis revealed 87,732 differentially methylated Cp G sites, representing approximately 12.41% of all sites in LCLs compared to primary B cells. The hypermethylated and hypomethylated Cp G sites were about 22.75% or 77.25%, respectively. Only 0.8% of hypomethylated sites and 4.5% of hypermethylated sites were located in Cp G islands, whereas 8.0% of hypomethylated sites and 16.3% of hypermethylated sites were located in shore（N_shore and S_shore）. Using principal component analysis of the DNA methylation profiles, primary B cells and LCLs could be accurately predicted. Gene Ontology（GO） and Kyoto Encyclopedia of Genes and Genomes（KEGG） analysis of differently methylated genes revealed that most of the top GO biological processes were related to cell activation and immune response, and some top enrichment pathways were related with activation and malignant transformation of human B cells.Conclusions： Our study demonstrated genome-wide DNA methylation variations between primary B cells and corresponding LCLs, which might yield new insight on the methylation mechanism of EBV-induced immortalization.

Clinicpathological Features of Gastric Cancer in Young Patients

The incidence of gastric cancer (GC) in young patients has showed a stable or even slightly increasing trend in recent years all over the world. Little is known about the clinicpathological features of young patients with GC in Ningxia region, located in the northwest part of China. To define the clinicpathological features of GC in young patients in this region, 117 patients with GC, who were admitted to the Department of Medical Oncology, General Hospital of Ningxia Medical University, Ningxia, China, were enrolled in a retrospective database between 2000 and 2005. The data from 55 patients aged less than 35 years old were compared with those from 62 controls aged between 36 and 70. It was found that in young group, the percentages of females, the tumors in the lower third of the stomach, tumor size larger than 4 cm, macroscopic type Borrmann III tumors, poorly differentiated histology, the 7th?T stage T3 + T4, the distribution of tumor-nodes-metastasis(TNM)stage IV, surgical exploratory laparoscopy, and anemia symptoms were significantly higher than those in the control group (P?< 0.05). The 5-year survival in the young group was lower than that in the control group (21.8%?vs.?48.4%,?P?< 0.05). It was obvious that the clinicpathological features of GC in young patients were different from those in the control group. Focusing on early diagnostic rate and choosing a suitable operative treatment should be critical to improve prognosis of young patients with GC in Ningxia region of China.

Hydroxylated metal–organic-layer nanocages anchoring single atomic cobalt sites for robust photocatalytic CO_(2) reduction

Assembly of two-dimensional(2D)metal–organic layers(MOLs)based on the hard and soft acid–base theorem represents an exquisite strategy for the construction of photocatalytic platforms in virtue of the highly exposed active sites,much improved mass transport,and greatly elevated stability.Herein,nanocages composed of MOLs are produced for the first time through a cosolvent approach utilizing zirconium-based UiO-66-(OH)2 as the structural precursor.To endow the catalytic activity for CO_(2) conversion,single atomic Co^(2+)sites are appended to the Zr-oxo nodes of the MOL cages,demonstrating a remarkable CO yield of 7.74 mmol·g^(-1)·h^(-1) and operational stability of 97.1%product retention after five repeated cycles.Such an outstanding photocatalytic performance is mainly attributed to the unique nanocage morphology comprising enormous 2D nanosheets for augmented Co^(2+)exposure and the abundant surface hydroxyl groups for local CO_(2) enrichment.This work underlines the tailoring of both metal–organic framework(MOF)morphology and functionality to boost the turnover rate of photocatalytic CO_(2) reduction reaction(CO_(2)RR).

土壤-植物体系中锌镉稳定同位素分馏研究进展

稳定同位素分馏技术对于示踪土壤-植物体系中重金属的迁移转化过程具有重要作用.本文阐述了土壤-植物体系中锌镉迁移转化主要涉及的土壤根际过程、根系吸收过程和根部-地上部转运过程及其对应产生的同位素分馏特征.在土壤根际过程,土壤固相对锌、镉的吸附解吸反应影响重金属在土壤溶液中的移动性和同位素组成:锌轻同位素、镉重同位素倾向于被土壤固相释放进入土壤溶液;植物根系活化作用则导致土壤固相结合的锌重同位素的释放.根系吸收过程影响土壤-植物间的同位素分馏:质外体吸附锌重同位素,共质体吸收过程中低亲合力转运系统产生锌轻同位素富集,高亲合力转运系统基本不产生分馏或略产生锌轻同位素富集;植物根系存在含硫基团结合镉,并且仅有低亲合力转运系统对镉轻同位素进行吸收转运.在根部-地上部转运过程,根部区室化作用影响植物体内重金属的迁移和地上部同位素组成:锌重同位素、镉轻同位素倾向于在根部储存,导致锌轻同位素、镉重同位素向地上部迁移.在土壤-植物体系中,锌镉同位素分馏现象存在明显差异,反映出植物对锌镉元素不同的吸收、转运和储存机制.

Combined amendment reduces soil Cd availability and rice Cd accumulation in three consecutive rice planting seasons

The scientific application of stabilized materials has been considered an effective method for the in situ remediation of Cd-contaminated soil.This study aimed to investigate the persistence of the effect of a combined amendment of limestone and sepiolite(LS)on soil Cd availability and accumulation in rice grown in a mildly Cd-contaminated paddy field(0.45 mg/kg of Cd)over three consecutive rice seasons.1125–4500 kg/ha of LS was applied to the soil before the first rice planting season and 562.5–2250 kg/ha of LS was supplemented before the third rice planting season.The application of LS(1125–4500 kg/ha)increased the soil p H by 0.44–1.09,0.18–0.53,and 0.42–0.68 in the first,second,and third season,respectively,and decreased the soil acid-extractable Cd content by 18.2–36.4%,17.7–33.5%,and9.6–17.6%.LS application significantly decreased the Cd contents in the rice tissues.The application of 4500 kg/ha of LS decreased the Cd content in brown rice to below the National Food Limit Standard of 0.2 mg/kg(GB 2762-2017)in the three consecutive rice seasons.However,the effect of LS on the soil-rice system was significantly weakened in the third season.The supplementary application of 562.5–2250 kg/ha of LS further decreased the Cd content in brown rice by 26.1–56.5%and decreased the health risk index by 23.7–43.8%.Therefore,it was recommended to apply 4500 kg/ha of LS in the first season and to supplement2250 kg/ha of LS in the third season to effectively guarantee the clean production of rice in three consecutive rice seasons.

Distribution and sources of polycyclic aromatic hydrocarbons and phthalic acid esters in water and surface sediment from the Three Gorges Reservoir

After the impoundment of the Three Gorges Reservoir（TGR）, the hydrological situation of the reservoir has changed greatly. The concentration and distribution of typical persistent organic pollutants in water and sediment have also changed accordingly. In this study, the concentration, distribution and potential sources of 16 polycyclic aromatic hydrocarbons（PAHs） and 6 phthalic acid esters（PAEs） during the water drawdown and impoundment periods were investigated in water and sediment from the TGR. According to our results, PAHs and PAEs showed temporal and spatial variations. The mean ΣPAH and ΣPAE concentrations in water and sediment were both higher during the water impoundment period than during the water drawdown period. The water samples from the main stream showed larger ΣPAH concentration fluctuations than those from tributaries. Both the PAH and PAE concentrations meet the Chinese national water environmental quality standard（GB 3838-2002）. PAH monomers with 2–3 rings and 4 rings were dominant in water, and 4-ring and 5–6-ring PAHs were dominant in sediment. Di-n-butyl phthalate（DBP） and di-2-ethylhexyl phthalate（DEHP）were the dominant PAE pollutants in the TGR. DBP and DEHP had the highest concentrations in water and sediment, respectively. The main source of PAHs in water from the TGR was petroleum and emissions from coal and biomass combustion, whereas the main sources of PAHs in sediments included coal and biomass combustion, petroleum, and petroleum combustion. The main source of PAEs in water was domestic waste, and the plastics and heavy chemical industries were the main sources of PAEs in sediment.

Vibration modes of flexoelectric circular plate

Beams,plates,and shells,as the fundamental mechanical structures,are widely used in microelectromechanical systems(MEMS)and nanoelectromechanical systems(NEMS)as sensors,actuators,energy harvesters,and among others.Deeply understand the electromechanical coupling of these dielectric structures is of crucial for designing,fabricating,and optimizing practice devices in these systems.Herein we demonstrate the electromechanical coupling in flexoelectric circular plate,in which higher-order strain gradients were considered to extend the classical electromechanical properties to isotropic materials,in which the non-uniform distribution of the electric potential along the radial direction was considered.Analytical solutions for the vibration modes of the flexoelectric circular plates showed that the dynamic modes were totally different from the piezoelectric circular plates owing to the inversion symmetry breaking by the strain gradient.The electromechanical coupling dynamic modes are sensitive to bending,twisting modes owing to the sensitivity of the flexoelectric effect to bending.This work provides a fundamental understanding of the electromechanical coupling in flexoelectric circular plate,which is helpful in designing novel flexoelectric circular plate-based devices,such as flexoelectric mirrors.

Hydrogen-Bonded Dopant-Free Hole Transport Material Enables Efficient and Stable Inverted Perovskite Solar Cells

Although many dopant-free hole transport materials(HTMs)for perovskite solar cells(PSCs)have been investigated in the literature,novel and useful molecular designs for high-performance HTMs are still needed.In this work,a hydrogen-bonding association system(NH⋯CO)between amide and carbonyl is introduced into the pure HTM layer.

Causal Effect of Genetically Determined Blood Copper Concentrations on Multiple Diseases: A Mendelian Randomization and Phenome-Wide Association Study

Exposures to copper have become a health concern.We aim to explore the broad clinical effects of blood copper concentrations.A total of 376,346 Caucasian subjects were enrolled.We performed a Mendelian randomization and phenome-wide association study(MR-PheWAS)to evaluate the causal association between copper and a wide range of outcomes in UK Biobank,and we constructed a protein-protein interaction network.We found association between blood copper concentrations and five diseases in the overall population and nine diseases in male.MR analysis implicated a causal role of blood copper in five diseases(overall population),including prostate cancer(OR=0.87,95%CI 0.77-0.98),malignant and unknown neoplasms of the brain and nervous system(OR=0.58,95%CI 0.38-0.89),and hypertension(OR=0.94,95%CI 0.90-0.98),essential hypertension(OR=0.94,95%CI 0.90-0.98)and cancer of brain and nervous system(OR=0.63,95%CI 0.41-0.98).For male,except for dysphagia being newly associated with blood copper(OR=1.39,95%CI 1.18-1.63),other MR results were consistent with the overall population.In addition,the PPI network showed possible relationship between blood copper and four outcomes,namely brain cancer,prostate cancer,hypertension,and dysphagia.Blood copper may have causal association with prostate cancer,malignant and unknown neoplasms of the brain and nervous system,hypertension,and dysphagia.Considering that copper is modifiable,exploring whether regulation of copper levels can be used to optimize health outcomes might have public health importance.

Myogenesis controlled by a long non-coding RNA 1700113A16RIK and post-transcriptional regulation

Long non-coding(lnc)RNA plays important roles in many cellular processes.The function of the vast majority of lncRNAs remains unknown.Here we identified that lncRNA-1700113A16RIK existed in skeletal muscle stem cells(MuSCs)and was significantly elevated during MuSC differentiation.Knockdown of 1700113A16RIK inhibits the differentiation of muscle stem cells.In contrast,overexpression of 1700113A16RIK promotes the differentiation of muscle stem cells.Further study shows the muscle specific transcription factor Myogenin(MyoG)positively regulates the expression of 1700113A16RIK by binding to the promoter region of 1700113A16RIK.Mechanistically,1700113A16RIK may regulate the expression of myogenic genes by directly binding to 3’UTR of an important myogenic transcription factor MEF2D,which in turn promotes the translation of MEF2D.Taken together,our results defined 1700113A16RIK as a positive regulator of MuSC differentiation and elucidated a mechanism as to how 1700113A16RIK regulated MuSC differentiation.

Pure-Blue Fluorescence Molecule for Nondoped Electroluminescence with External Quantum Efficiency Approaching 13%

A pure-blue light-emitting material is one of the key components in the preparation of organic lightemitting diode(OLED)displays.Although highefficiency blue OLEDs have been realized in thermally activated delayed fluorescence(TADF)materials,they need to be dispersed into suitable hostmaterials.Hence,exploring efficient nondoped,pure-blue luminous molecules is important.