NAC transcription factor ATAF1 negatively modulates the PIF-regulated hypocotyl elongation under a short-day photoperiod.

Day length modulates hypocotyl elongation in seedlings to optimize their overall fitness. Variations in cell growth-associated genes are regulated by several transcription factors. However, the specific transcription factors through which the plant clock increases plant fitness are still being elucidated. In this study, we identified the no apical meristem, Arabidopsis thaliana-activating factor (ATAF-1/2), and cup-shaped cotyledon (NAC) family transcription factor ATAF1 as a novel repressor of hypocotyl elongation under a short-day (SD) photoperiod. Variations in day length profoundly affected the transcriptional and protein levels of ATAF1. ATAF1-deficient mutant exhibited increased hypocotyl length and cell growth-promoting gene expression under SD conditions. Moreover, ATAF1 directly targeted and repressed the expression of the cycling Dof factor 1/5 (CDF1/5), two key transcription factors involved in hypocotyl elongation under SD conditions. Additionally, ATAF1 interacted with and negatively modulated the effects of phytochrome-interacting factor (PIF), thus inhibiting PIF-promoted gene expression and hypocotyl elongation. Taken together, our results revealed ATAF1-PIF as a crucial pair modulating the expression of key transcription factors to facilitate plant growth during day/night cycles under fluctuating light conditions.

Local symmetry-driven interfacial magnetization and electronic states in (ZnO)n/(w-FeO)n superlattices.

Superlattices constructed with the wide-band-gap semiconductor ZnO and magnetic oxide FeO, both in the wurtzite structure, have been investigated using spin-polarized first-principles calculations. The structural, electronic and magnetic properties of the (ZnO)n/(w-FeO)n superlattices were studied in great detail. Two different interfaces in the (ZnO)n/(w-FeO)n superlattices were identified and they showed very different magnetic and electronic properties. Local symmetry-driven interfacial magnetization and electronic states can arise from different Fe/Zn distributions at different interfaces or spin ordering of Fe in the superlattice. The local symmetry-driven interfacial magnetization and electronic states, originating either from different Fe/Zn distribution across interfaces I and II, or by spin ordering of Fe in the superlattice, can be identified. It was also found that, in the case of the ferromagnetic phase, the electrons are more delocalized for the majority spin but strongly localized for the minority spin, which resulted in interesting spin-dependent transport properties. Our results will pave the way for designing novel spin-dependent electronic devices through the construction of superlattices from semiconductors and multiferroics.

Influence of Zr aggregation on Li-ion conductivity of amorphous solid-state electrolyte Li-La-Zr-O.

In our study, we investigated the influence of the local structure of amorphous Li-La-Zr-O (a-LLZO) on Li-ion conductivity using ab initio molecular dynamics (AIMD). A-LLZO has shown promising properties in inhibiting the growth of lithium dendrites, making it a potential candidate for solid electrolytes in all-solid-state lithium batteries. The low Li-ion conductivity of a-LLZO is currently limiting its practical applications. Our findings revealed that the homogeneous distribution of Zr-O polyhedra within the pristine structure of a-LLZO contributes to enhanced Li-ion conductivity. By reducing the interconnections among Zr-O polyhedra, the AIMD-simulated a-LLZO sample achieved a Li-ion conductivity of 5.78 × 10-4 S/cm at room temperature, which is slightly lower than that of cubic LLZO (c-LLZO) with a Li-ion conductivity of 1.63 × 10-3 S/cm. Furthermore, we discovered that Li-ion conductivity can be influenced by adjusting the elemental ratios within a-LLZO. This suggests that fine-tuning the composition of a-LLZO can potentially further enhance its Li-ion conductivity and optimize its performance as a solid electrolyte in lithium batteries.

Quantum spin Hall effect in tilted penta silicene and its isoelectronic substitutions.

Silicene, a competitive two-dimensional (2D) material for future electronic devices, has attracted intensive attention in condensed matter physics. Utilizing an adaptive genetic algorithm (AGA), we identify a topological allotrope of silicene, named tilted penta (tPenta) silicene. Based on first-principles calculations, the geometric and electronic properties of tPenta silicene and its isoelectronic substitutions (Ge, Sn) are investigated. Our results indicate that tPenta silicene exhibits a semimetallic state with distorted Dirac cones in the absence of spin-orbit coupling (SOC). When SOC is considered, it shows semiconducting behavior with a gap opening of 2.4 meV at the Dirac point. Based on the results of invariant ( = 1) and the helical edge states, we demonstrate that tPenta silicene is a topological insulator. Furthermore, the effect of isoelectronic substitutions on tPenta silicene is studied. Two stoichiometric phases, i.e., tPenta Si0.333Ge0.667 and tPenta Si0.333Sn0.667 are found to retain the geometric framework of tPenta silicene and exhibit high stabilities. Our calculations show that both tPenta Si0.333Ge0.667 and tPenta Si0.333Sn0.667 are QSH insulators with enlarged band gaps of 32.5 meV and 94.3 meV, respectively, at the HSE06 level, offering great potential for practical applications at room temperature.

Synthesis and antitumor evaluation of (aryl)methyl-amine derivatives of dehydroabietic acid-based B ring-fused-thiazole as potential PI3K/AKT/mTOR signaling pathway inhibitors.

In an attempt to search for new natural product-based antitumor agents, a series of novel (aryl)methyl-amine derivatives of dehydroabietic acid-based B ring-fused-thiazole were designed and synthesized. The primary bioassay showed that compounds 5r and 5s presented certain inhibitory activity against cancer cells, weak cytotoxic activity against normal cells, and inhibitory activity against PI3K/AKT/mTOR signaling pathway. The binding modes and the binding site interactions between the active compounds and the target proteins were predicted preliminarily by the molecular docking method.

A super-stretchable boron nanoribbon network.

We have studied the mechanical properties of a two-dimensional (2D) boron nanoribbon network (BNRN) subjected to a uniaxial or a biaxial tensile strain using first principles calculations. The results show that the 2D BNRN is super-stretchable. The critical tensile strains of the BNRN in the χ-h1 phase along the a- and b-directions are 0.51 and 0.41, respectively, and that for the biaxial strain reaches an ultrahigh value of 0.84. By analyzing the B-B interatomic distance, coordination number and charge distribution, it is found that with increasing biaxial tensile strain, the χ-h1 BNRN undergoes two structural phase transitions, which are characterized by breaking of the B-B bonds and the partial transformation of the nanoribbon-like structures into chain-like structures. The strain-induced phase transitions significantly reduce the strain energy. We also discuss the elastic constants, Young's modulus, shear modulus, and Poisson's ratios. The super-stretchable and flexible mechanical properties of the BNRNs, together with their superior transport properties, make BNRNs useful in a wide range of applications in nanoscale electronic devices.

High anisotropy of fully hydrogenated borophene.

We have studied the mechanical properties and phonon dispersions of fully hydrogenated borophene (borophane) under strains by first principles calculations. Uniaxial tensile strains along the a- and b-direction, respectively, and biaxial tensile strain have been considered. Our results show that the mechanical properties and phonon stability of borophane are both highly anisotropic. The ultimate tensile strain along the a-direction is only 0.12, but it can be as large as 0.30 along the b-direction. Compared to borophene and other 2D materials (graphene, graphane, silicene, silicane, h-BN, phosphorene and MoS2), borophane presents the most remarkable anisotropy in in-plane ultimate strain, which is very important for strain engineering. Furthermore, the phonon dispersions under the three applied strains indicate that borophane can withstand up to 5% and 15% uniaxial tensile strain along the a- and b-direction, respectively, and 9% biaxial tensile strain, indicating that mechanical failure in borophane is likely to originate from phonon instability.

Degenerate Effect on the Mobility of Holes in Graphane: A Study Based on Density Functional Theory Coupled with Deformation Potential Theory.

The traditional deformation potential method is not able to calculate the charge mobility of heavily doped degenerate semiconductors, in which inter-band scattering is not negligible. To theoretically predict the charge mobility of such semiconductors, an improved deformation potential method is required, in which the deformation potential constant is decomposed into two parts (hydrostatic and uniaxial terms) based on k⋅p theory to incorporate the inter-band scattering between degenerate valence bands. We propose a new method to calculate the heavy- and light-hole mobilities of graphane. The proposed method produces more appropriate values than the traditional methods. Hence, the new method can be applied to other 2D materials with degenerate bands.

Unveiling the synthesis of aromatic compounds in sauce-flavor Daqu from the functional microorganisms to enzymes.

Aromatic compounds serve as the primary source of floral and fruity aromas in sauce-flavor (Maotai flavor) baijiu, constituting the skeleton components of its flavor profile. Nevertheless, the formation mechanism of these compounds and key aroma-producing enzymes in sauce-flavor Daqu (fermentation agent, SFD) remain elusive. Here, we combined metagenomics, metaproteomics, metabolomics, and key enzyme activity to verify the biosynthesis pathway of aromatic compounds and to identify key enzymes, genes, and characteristic microorganisms in SFD. The results showed that the later period of fermentation was critical for the generation of aromatic compounds in SFD. In-situ verification was conducted on the potential key enzymes and profiles in various metabolites, providing comprehensive evidence for the main synthetic pathways of aromatic compounds in SFD. Notably, our results showed that primary amine oxidase (PrAO) and aldehyde dehydrogenase (ALDH) emerged as two key enzymes promoting aromatic compound synthesis. Additionally, two potential key functional genes regulating aromatics generation were identified during SFD fermentation through correlation analysis between proteins and relevant metabolites, coupled with in vitro amplification test. Furthermore, original functional strains (Aspergillus flavus-C10 and Aspergillus niger-IN2) exhibiting high PrAO and ALDH production were successfully isolated from SFD, thus validating the results of metagenomics and metaproteomics analyses. This study comprehensively elucidates the pathway of aromatic compound formation in SFD at the genetic, proteomic, enzymatic, and metabolomic levels, providing new ideas for the investigation of key flavor substances in baijiu. Additionally, these findings offer valuable insights into the regulatory mechanisms of aromatic compounds generation.

The relationship between physical exercise and smoking behavior among Chinese residents aged 16 years and older.

To explore the relationship between physical exercise and smoking behavior among Chinese residents aged 16 years and older. Analysis based on 29,466 validated cases in the 2018 China Family Panel Studies (CFPS 2018). The chi-square test and Mann-Whitney U test were used for comparative analysis between groups. Logistic regression analysis was used to explore the relationship between physical exercise and smoking behavior. Gender and birth cohort differences in the relationship between physical exercise and smoking behavior were explored based on stratified regression analysis using gender and birth cohort as stratified variables, respectively. Robustness testing based on multiple linear regression analysis using a replacement data approach. There were 8735 cases of smokers among the respondents. After controlling for relevant confounders, there was a significant negative association between physical exercise and smoking behavior among residents [OR 0.718, 95% CI (0.673, 0.765), P < 0.01]. Physical exercise was more significantly associated with smoking behavior among male residents [OR 0.694, 95% CI (0.649, 0.743), P < 0.01], while it was not significantly associated with smoking behavior among female residents [OR 0.901, 95% CI (0.743, 1.093), P > 0.05]. Physical exercise was more significantly associated with smoking behavior in the pre-1948 (OR 0.748), 1959-1968 (OR 0.748), 1969-1978 (OR 0.812), 1989-1998 (OR 0.576) and post-1999 (OR 0.411) birth cohorts, and the association decreased over time and with social change. The results of the robustness test showed that frequency of exercise was significantly and negatively associated with smoking behavior among residents [OR 0.961, 95% CI (0.951, 0.970), P < 0.01]. Physical exercise is negatively associated with smoking behavior among Chinese residents aged 16 years and older, especially among male residents. There is a cohort effect between physical exercise and smoking behavior of the population, that is, the relationship between the two decreases with social change.

HCHs and DDTs in soils around Guanting Reservoir in Beijing, China: spatial-temporal variation and countermeasures.

The concentrations of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in the topsoil samples around the Guanting Reservoir in Beijing were measured, and their spatial distribution and environmental risks were analyzed by GIS. The results showed that in 2003, 2007, and 2009, the HCHs concentrations were 0.66, 0.85, and 0.73 ng/g, and the DDTs concentrations were 9.50, 7.80, and 6.46 ng/g in the studied area, respectively. In the topsoil, the HCHs concentrations did not change much while the DDTs concentrations declined steadily. Most of the current residues in soil come from the POPs used in the past years but some new input is also detected in certain regions. The level of HCHs and DDTs residues in the south reservoir is lower than that in the north reservoir. The middle region has the highest HCHs and DDTs concentrations, especially near the Beixinpu town. The high risk regions of pollution of HCHs and DDTs are mainly distributed in the vicinity of Beixinpu town as well. Based on the aforementioned results, a comprehensive countermeasure is proposed entailing decision making, local implementation, scientific support, and public participation with regard to the long-term control and management of POPs around the Guanting Reservoir.

The effects of an innovative pulping technique of synchronously pulping and gelatinizing treatment on raw materials properties, oenological parameters, fermentation process, and flavor characteristics of glutinous rice wine.

Liquid-state fermentation has been increasingly applied in the industrial glutinous rice wine (GRW) production. However, products brewed by this emerging technique possess some deficiencies in flavor quality. Therefore, this study firstly developed and optimized an innovative pulping technique by the synchronously pulping and gelatinizing treatment (Process I) to improve GRW flavor quality, and then revealed the influences of Process I on raw materials properties, oenological parameters, fermentation process, and flavor characteristics of GRW. Results show that Process I significantly (p < 0.05) enriched the soluble solid and crude protein content of glutinous rice milk by improving gelatinization degree and pulping efficiency, which consequently enhanced the microbial growth, glycolysis, and protein decomposition during the GRW fermentation process. GC-MS analysis shows that Process I sequentially significantly (p < 0.05) enhanced the esterification and Ehrlich or Harrison pathway during the fermentation process. This contributed to a higher content of key ester and alcohol compounds. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01119-7.

Identification of Two Myrosinases from a Leclercia adecarboxylata Strain and Investigation of Its Tolerance Mechanism to Glucosinolate Hydrolysate.

Glucosinolates (GSLs), secondary metabolites synthesized by cruciferous plants, can be hydrolyzed by myrosinase into compounds, such as isothiocyanates (ITCs), with various bioactivities. Thus, myrosinase plays an important role in the utilization of GSLs. We isolated a bacterial strain, which was identified as Leclercia adecarboxylata, from the rhizosphere soil of rape seedlings and identified two myrosinase genes and an ITC hydrolase gene. Both myrosinases are intracellular and have 658 amino acid residues. Via molecular docking and chemical modification assays investigating the active sites of the myrosinases, arginine was found to be essential for their catalytic activity. Transcriptomic analysis of the response to sinigrin revealed significant up-regulation of some genes involved in allyl-ITC detoxification, with metallo-ß-lactamase 3836 having the highest fold change. Thus, we discovered two myrosinases from L. adecarboxylata and demonstrated that the mechanism of tolerance of the bacterium to allyl-ITC likely involved metallo-ß-lactamase activity.

Inorganic Lead-Free B-γ-CsSnI3 Perovskite Solar Cells Using Diverse Electron-Transporting Materials: A Simulation Study.

B-γ-CsSnI3 perovskite solar cells (PSCs) are simulated employing diverse electron-transporting layers (ETLs, including TiO2, ZnO, SnO2, GaN, C60, and PCBM), and a comparative study has been made. Both regular and inverted planar structures are simulated. Effects of the thickness of absorbers and ETLs, doping of ETLs, and interface trap states on the photovoltaic performance are studied to optimize the device structures. The regular structures have larger short-circuit current density (J sc) than the inverted structures, but the inverted structures have larger fill factor (FF). All of the simulated optimal PSCs have similar open-circuit voltages (V oc) of ∼0.96 V. The PSCs with TiO2 ETLs have the best photovoltaic performance, and the optimum structure exhibits the highest efficiency of 20.2% with a V oc of 0.97 V, J sc of 29.67 mA/cm2, and FF of 0.70. The optimal PSCs with ZnO, GaN, C60, and PCBM ETLs exhibit efficiencies of 17.88, 18.09, 16.71, and 16.59%, respectively. The optimal PSC with SnO2 ETL exhibits the lowest efficiency of 15.5% in all of the simulated PSCs due to its cliff-like band offset at the SnO2/CsSnI3 interface. Furthermore, the increase of interface trap density and capture cross section is found to reduce the photovoltaic performance of PSCs. This work contributes to designing and fabricating CsSnI3 PSCs.

Whole-Exome Sequencing Identified a Novel Homozygous Frameshift Mutation of HPS3 in a Consanguineous Family with Hermansky-Pudlak Syndrome.

Hermansky-Pudlak syndrome (HPS) is a rare genetic disorder with an autosomal recessive inherited pattern. It is mainly characterized by deficiencies in lysosome-related organelles, such as melanosomes and platelet-dense granules, and leads to albinism, visual impairment, nystagmus, and bleeding diathesis. A small number of patients will present with granulomatous colitis or fatal pulmonary fibrosis. At present, mutations in ten known genetic loci (HPS1-11) have been identified to be the genetic cause of HPS. In this study, we enrolled a consanguineous family who presented with typical HPS phenotypes, such as albinism, visual impairment, nystagmus, and bleeding diathesis. Whole-exome sequencing and Sanger sequencing were applied to explore the genetic lesions of the patient. A novel homozygous frameshift mutation (NM_032383.5, c.1231dupG/p.Aps411GlyfsTer32) of HPS3 was identified and cosegregated in the family members. Furthermore, real-time PCR confirmed that the mutation decreased the expression of HPS3, which has been identified as the disease-causing gene of HPS type 3. According to ACMG guidelines, the novel mutation, resulting in a premature stop codon at amino acid 442, is a pathogenic variant. In summary, we identified a novel mutation (NM_032383.5, c.1231dupG/p.Aps411GlyfsTer32) of HPS3 in a family with HPS. Our study expanded the variant spectrum of the HPS3 gene and contributed to genetic counseling and prenatal genetic diagnosis of the family.

Association Between Time to Endovascular Therapy and Outcomes in Patients With Acute Basilar Artery Occlusion.

OBJECTIVE: To characterize the association of onset to puncture time (OPT) with clinical outcomes among patients with acute basilar artery occlusion receiving endovascular therapy (EVT) in clinical practice. METHODS: Using the EVT for Acute Basilar Artery Occlusion (BASILAR) study, we identified consecutive patients with acute basilar artery occlusion receiving EVT in 47 comprehensive stroke centers in China from January 2014 to May 2019. The primary outcome was favorable functional outcome (defined as modified Rankin Scale score [mRS] 0-3) at 90 days. Secondary outcomes included function independence (mRS 0-2), mortality, and symptomatic intracerebral hemorrhage. The associations of OPT with clinical outcomes were analyzed using multivariable logistic regression (OPT as a categorical variable) and restricted cubic spline regression (OPT as a continuous variable). RESULTS: Among 639 eligible patients, the median age was 64 years, and median OPT was 328 minutes (interquartile range 220-490). Treatment within 4-8 hours and 8-12 hours was associated with lower rates of favorable outcome (adjusted odds ratio, 0.63 [95% confidence interval (CI), 0.40-0.98] and 0.47 [95% CI, 0.23-0.93], respectively) compared with treatment within 4 hours. Restricted cubic spline regression analysis showed that the OPT had L-shaped associations with favorable outcome (p nonlinearity = 0.028) and functional independence (p nonlinearity = 0.025), with significant benefit loss throughout the first 9 hours, but then appeared relatively flat. The odds of mortality increased relatively for OPT up to 9 hours, but then leveled off (p nonlinearity = 0.042). The association between symptomatic intracerebral hemorrhage and OPT was not significant. CONCLUSION: Among patients with acute basilar artery occlusion in routine practice, earlier treatment with EVT was associated with better outcomes throughout the first 9 hours after onset, but benefit may sustain unchanged afterwards. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with acute ischemic stroke due to basilar artery occlusion, earlier EVT is associated with better outcomes.

Two-step biological approach for treatment of rapeseed meal.

Rapeseed meal (RSM) is an important source of protein, but its value is limited due to the poor digestibility and the presence of many antinutritional factors. In this study, a two-step biological method was developed for detoxifying RSM and increasing its protein value. In the first stage, various detoxifying enzymes and proteases were produced by Aspergillus niger during solid-state fermentation (SSF). In the second stage, coordinated enzymatic hydrolysis was employed to further degrade the antinutritional factors and macromolecular proteins in the fermented RSM. Following fermentation at 30 °C for 48 hr and enzymatic hydrolysis at 45 °C for 24 hr, the content of trichloroacetic acid soluble protein (TCA-SP) and glucosinolates (GLS) in RSM was increased by 81.70% and reduced by 30.06%, respectively, compared with that obtained using the SSF process alone. Moreover, to improve the efficiency of enzymatic hydrolysis, the yield of acid protease was increased by optimizing the composition of the medium so that the TCA-SP content was increased to 208.39 mg/g and accounted for 51.62% of the total RSM protein, which was 99.36% and 629.66% higher than that in the fermented RSM and control, respectively. Overall, these results demonstrate that the two-step process could be more effective for the degradation of the antinutritional factors and improvement of the protein quality of RSM compared to use of the SSF method alone, which may improve the utilization of RSM in food and animal feed. PRACTICAL APPLICATION: Rapeseed meal (RSM) is a protein source that provides high-quality nutrition and can be applied to the development of value-added products for humans and animal feed. To improve the utilization of RSM, a combined method of solid-state fermentation and enzymatic digestion was developed. Compared with the traditional solid-state fermentation method, the present method further improves the quality of RSM and demonstrates improved efficacy in increasing the small peptide content while reducing the levels of antinutritional factors.

[Spatio-temporal Variations in the Characteristics of Water Eutrophication and Sediment Pollution in Baiyangdian Lake].

Since the establishment of Xiong'an New District, a series of comprehensive pollution control measures have been implemented in Baiyangdian Lake. To evaluate the pollution status and identify the main sources of pollution of Baiyangdian Lake, 30 water samples and 29 sediment samples were collected in the lake. Five water quality indexes (i.e., concentrations of chemical oxygen demand, total phosphorus (TP), total nitrogen (TN), NH4+-N, and chlorophyll-a) and three sediment quality indexes (i.e., concentrations of TN, TP, and heavy metals) were measured. Along with historical monitoring data, the spatio-temporal pollution characteristics and their influencing factors in Baiyangdian Lake were analyzed. The results show that the Baiyangdian Lake water is eutrophicated. Of the 30 sampling sites, 8 are "mildly eutrophicated" (accounting for 26.7%), 16 are "moderately eutrophicated" (accounting for 53.3%), and 6 are "severely eutrophicated" (accounting for 20%). Compared with the periods between 1991 and 2017, the water quality of most sampling sites, especially in the northern parts, has improved a lot. This shows that the pollution control measures have basically curbed the gradually increasing trend of pollution in the waterbody. The nutritive pollution in sediment is severe. The concentrations of TN are between 1483.7 and 14234.1 mg·kg-1, with a mean value of 5054.9 mg·kg-1, and the concentration coefficient variation in different sites is as high as 46.5%. The concentrations of TP are between 360.3 and 1964.4 mg·kg-1, with a mean value of 925.4 mg·kg-1, and the concentration coefficient variation in different sites is 25.7%. Geoaccumulation index calculation shows that the mean Igeo value of heavy metals in sediments is less than 1, which indicates cleanness or slight pollution. The main contributions to heavy metal pollution are Cd, Zn, and Cu. Regarding ecological risk of heavy metals, only some sites (i.e., L3, L21, L28, and L29) are at high and very high risk level, while the remaining sites are at moderate risk level. Overall, the pollution of Baiyangdian Lake changes from the northern part to the southern part, and the main influencing factors also change from external pollution to endogenous pollution caused by the discharge of villages in the lake and the sediments.

[Spatial Characteristics and Ecological Risks of Perfluoroalkyl Substances in Coastal Urbanized Areas of China and South Korea].

This study concentrated on the 15 perfluoroalkyl substances (PFASs) in the coastal areas of China and South Korea, an urbanized area with intensive human activities. In total, 126 water samples and 125 sediment samples were collected and determined by HPLC-MS/MS. Fifteen PFASs were detected at least once in all the sites. The total concentrations of PFASs in water and sediment samples ranged from 6.75 ng·L-1 to 20982 ng·L-1 and from 0.229 ng·g-1 to 53.8 ng·g-1 (dw), respectively. The concentrations of PFASs in waters and sediments were relatively high in China, and PFOA was the predominant PFAS. In contrast, short chain compounds such as PFBA and PFPeA played a major role in water, and PFOS, PFBA, and PFOA dominated the sediment samples in South Korea. The partition coefficients of PFASs were closely related to the fraction of organic carbon in the sediment and the carbon chain length of PFASs. Among the 15 compounds, the partition coefficients of 9 were significantly correlated with the fraction of organic carbon (r>0.21, P<0.05), and the partition coefficient steadily increased with the increase of the carbon chain length. The results of ecological risk assessment suggested that the coastal urbanized areas of China and South Korea are still at a low risk. However, some specific areas also showed PFAS pollution. More attention should be paid to the potential health risks.

A new strategy for assembling multifunctional nanocomposites with iron oxide and amino-terminated PAMAM dendrimers.

A new strategy for assembling multifunctional nanocomposites with magnetic particles and amino dendrimers was reported. In this strategy, the amino terminated PAMAM G5.0 and Fe(3)O(4) NPs prepared by co-deposition method and further modified by aminosilane by two sol-gel processes were combined with the hydrophilic spacer of PEG dicarboxylate by amidation. The nanocomposites were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), atom force microscopy (AFM), superconducting quantum interference device (SQUID) magnetometer, and hydrophilicity analysis. The results showed that the multifunctional nanocomposites were spherical with the mean diameter of 180 nm and exhibited good dispersion and hydrophilicity. The new strategy put forward here provides an effective route to functionalizing Fe(3)O(4) NPs with various amino dendrimers for drug and gene delivery as well as biological detection.