Charge-assisted hydrogen bonding in a bicyclic amide cage: an effective approach to anion recognition and catalysis in water.

Hydrogen bonding is prevalent in biological systems, dictating a myriad of life-sustaining functions in aqueous environments. Leveraging hydrogen bonding for molecular recognition in water encounters significant challenges in synthetic receptors on account of the hydration of their functional groups. Herein, we introduce a water-soluble hydrogen bonding cage, synthesized via a dynamic approach, exhibiting remarkable affinities and selectivities for strongly hydrated anions, including sulfate and oxalate, in water. We illustrate the use of charge-assisted hydrogen bonding in amide-type synthetic receptors, offering a general molecular design principle that applies to a wide range of amide receptors for molecular recognition in water. This strategy not only revalidates the functions of hydrogen bonding but also facilitates the effective recognition of hydrophilic anions in water. We further demonstrate an unconventional catalytic mechanism through the encapsulation of the anionic oxalate substrate by the cationic cage, which effectively inverts the charges associated with the substrate and overcomes electrostatic repulsions to facilitate its oxidation by the anionic MnO4 -. Technical applications using this receptor are envisioned across various technical applications, including anion sensing, separation, catalysis, medical interventions, and molecular nanotechnology.

[Analysis of Heavy Metal Sources in Farmland Soil of Sewage Irrigation and Industrial Complex Area Based on APCS-MLR and PMF].

The contents of eight heavy metals （Cr, Ni, Cu, Zn, Cd, Pb, As, and Hg） were determined based on the surface soil samples of sewage irrigation and industrial complex in Kaifeng City. The absolute factor analysis-multiple linear regression （APCS-MLR） model and positive matrix factorization （PMF） model were used to analyze the sources and contribution rates of heavy metals in soil combined with correlation analysis and systematic cluster analysis. The results showed that： ① The average values of ω（Cr）, ω（Ni）, ω（Cu）, ω（Zn）, ω（Cd）, ω（Pb）, ω（As）, and ω（Hg） in the study area were 52.19, 25.00, 42.03, 323.53, 1.79, 53.45, 9.43, and 0.20 mg·kg-1, respectively, and Cr, Ni, and As are lower than the background values of tidal soil. Cu, Zn, Cd, Pb, and Hg are higher than the background values of the tidal soil. ② There were four sources of the eight heavy metals： natural sources, agricultural sewage irrigation sources, industrial atmospheric sedimentation sources, and transportation sources. Cr and Ni were mainly from natural sources； Cu, Zn, Cd, and Pb were mainly from agricultural sewage irrigation and transportation sources； As was mainly from natural sources and agricultural sewage irrigation； and Hg was mainly from industrial atmospheric sedimentation. ③ The APCS-MLR and PMF source analysis results indicated that industrial and agricultural activities were the main sources of heavy metals in the soil of the study area. The average contribution rates of APCS-MLR in the nine sampling areas of the research area were 76.01% （natural sources and agricultural sewage irrigation sources）, 22.71% （industrial atmospheric sedimentation sources and transportation sources）, and 1.28% （unknown sources）. The average contribution rates of PMF were 59.66% （natural sources and agricultural sewage irrigation sources） and 40.34% （industrial atmospheric sedimentation sources and transportation sources）. The source analysis results of the LZ, XZ, NLT, PT, YLZ, and BC models were basically consistent, and WL was better in the APCS-MLR model, whereas SG and QT were better in the PMF model. The research results can provide a scientific basis for the prevention and control of soil heavy metal pollution and environmental remediation.

The efficacy and safety of combined therapy with endobronchial tamponade and bronchial artery embolization for massive hemoptysis.

BACKGROUND: Massive hemoptysis is characterized by its life-threatening nature, potentially leading to airway obstruction and asphyxia. The objective of this study was to evaluate the clinical effectiveness of combining endobronchial tamponade with bronchial artery embolization (BAE) in the treatment of massive hemoptysis. METHODS: Between March 2018 and March 2022, a total of 67 patients with massive hemoptysis who underwent BAE were divided into two groups: the combination group (n = 26) and the BAE group (n = 41). Technical and clinical success rates were assessed, and adverse events were monitored following the treatment. Blood gas analysis and coagulation function indicators were collected before and after the treatment, and recurrence and survival rates were recorded during the follow-up period. RESULTS: All patients achieved technical success. There were no significant differences in the clinical success rate, recurrence rates at 3 and 6 months, and mortality rates at 3 months, 6 months, and 1 year between the combination group and the BAE group. However, the hemoptysis recurrence rate at 1 year was significantly lower in the combination group compared to the BAE group (15.4% vs. 39.0%, P = 0.039). No serious adverse events were reported in either group. After treatment, the combination group showed higher levels of arterial partial pressure of oxygen (PaO2), oxygenation index (PaO2/FiO2), fibrinogen (FIB), and D-dimer (D-D) compared to the BAE group (P < 0.05). Multivariate regression analysis demonstrated a significant correlation between combined therapy and hemoptysis-free survival. CONCLUSION: Combination therapy, compared to embolization alone, exhibits superior efficacy in improving respiratory function, correcting hypoxia, stopping bleeding, and preventing recurrence. It is considered an effective and safe treatment for massive hemoptysis.

[Source Apportionment and Health Risk Assessment of Heavy Metals in Dust Around Bus Stops in Kaifeng City Based on APCS-MLR Model].

In order to reveal the influence of urban transportation systems on the quality of urban ecological environment, this study selected surface dust from bus stops, which is strongly disturbed by transportation, as the research object. The contents of eight heavy metals (V, Cr, Co, Ni, Cu, Zn, Cd, and Pb) in the dust were determined through inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectroscopy (ICP-ASE). The spatial distribution characteristics and pollution levels of the eight heavy metals in the dust were analyzed using the geo-accumulation index method. A combined qualitative (correlation analysis and principal component analysis) and quantitative (absolute principal component scores-multiple linear regression model (APCS-MLR)) method was used to explore the sources of heavy metals in surface dust near bus stops. The spatial distribution characteristics of heavy metals from different sources were elucidated using the Kriging interpolation method. The health risk assessment model proposed by the United States Environmental Protection Agency was used to evaluate the human health risks. The results showed that the average values of ω(V), ω(Cr), ω(Co), ω(Ni), ω(Cu), ω(Zn), ω(Cd), ω(Pb), and ω(As) in the bus stop surface dust were 68.36, 59.73, 5.81, 19.34, 40.10, 208.32, 1.01, and 49.46 mg·kg-1, respectively. The concentrations of heavy metals (Cd, Zn, Pb, Cu, and Cr) in the dust were all higher than the background values in the surrounding dust, exceeding them by 3.37, 2.70, 2.01, 1.95, and 1.28 times, respectively. The order of the geo-accumulation index for the eight heavy metals was Cd > Zn > Pb > Cu > Cr > V > Ni > Co, with Cd, Zn, Cu, and Pb in the dust indicating mild pollution levels and the others showing no pollution. The source analysis results showed that Cr, Co, and Ni were natural sources, whereas Cu, Zn, Pb, and Cd were traffic sources, and V was derived from a combination of industrial and natural sources. The APCS-MLR results indicated that the average contribution rates of the four sources were as follows:natural source (34.17 %), traffic source (29.84 %), industrial-natural mixed source (14.64 %), and unknown source (21.35 %). The spatial distribution map of the contribution rate of the traffic source was consistent with the trends of traffic volume and bus route density distribution. According to the health risk assessment, the cancer risk and non-cancer risk for children were both higher than those for adults. Cr was the main non-cancer factor, and Cd was the main cancer-causing factor. Natural and traffic sources contributed the most to non-cancer risk and cancer risk, respectively.

Transcriptomic Analysis of Alternative Splicing Events during Different Fruit Ripening Stages of Coffea arabica L.

To date, genomic and transcriptomic data on Coffea arabica L. in public databases are very limited, and there has been no comprehensive integrated investigation conducted on alternative splicing (AS). Previously, we have constructed and sequenced eighteen RNA-seq libraries of C. arabica at different ripening stages of fruit development. From this dataset, a total of 3824, 2445, 2564, 2990, and 3162 DSGs were identified in a comparison of different fruit ripening stages. The largest proportion of DSGs, approximately 65%, were of the skipped exon (SE) type. Biologically, 9 and 29 differentially expressed DSGs in the spliceosome pathway and carbon metabolism pathway, respectively, were identified. These DSGs exhibited significant variations, primarily in S1 vs. S2 and S5 vs. S6, and they involve many aspects of organ development, hormone transduction, and the synthesis of flavor components. Through the examination of research findings regarding the biological functions and biochemical pathways associated with DSGs and DEGs, it was observed that six DSGs significantly enriched in ABC transporters, namely, LOC113712394, LOC113726618, LOC113739972, LOC113725240, LOC113730214, and LOC113707447, were continually down-regulated at the fruit ripening stage. In contrast, a total of four genes, which were LOC113732777, LOC113727880, LOC113690566, and LOC113711936, including those enriched in the cysteine and methionine metabolism, were continually up-regulated. Collectively, our findings may contribute to the exploration of alternative splicing mechanisms for focused investigations of potential genes associated with the ripening of fruits in C. arabica.

Horizontal Plane Haptic Redirection: Realizing Haptic Feedback for the Virtual Inclined Plane in VR.

Some interactions in virtual environments need to be operated on inclined planes. If a real inclined plane can be found in the real environment that corresponds exactly to the angle of the virtual inclined plane to provide haptic feedback, the user's immersion can be enhanced. However, it is not easy to find such a real inclined plane in the real environment. We proposed a horizontal plane haptic redirection scheme, where users interacting with virtual inclined planes in virtual environments can obtain haptic feelings by using real horizontal planes that are easily available in the real world for redirection mapping. We also designed an integrated solution to locate the real horizontal plane and for haptic redirection based on the Vive Pro headset. Then we measured the angle and size thresholds for horizontal plane haptic redirection as 20° and 88%, respectively, through a user study. Through experiments, we also found that when the degree of redirection exceeded the threshold, the user's operation efficiency would be significantly reduced. In addition, we compared the horizontal plane haptic redirection scheme with the scheme without redirection and the scheme without haptic feedback to demonstrate the validity and necessity of the redirection scheme proposed in this paper.

Inhibition of FABP5 attenuates inflammatory bowel disease by modulating macrophage alternative activation.

Fatty acid binding protein 5 (FABP5) is an intracellular chaperone of fatty acid molecules that regulates lipid metabolism and cell growth. However, its role in intestinal inflammation remains enigmatic. Through examination of human tissue samples and single-cell data, we observed a significant upregulation of FABP5 within the mucosa of patients afflicted with ulcerative colitis (UC) and Crohn's disease (CD), predominantly localized in intestinal macrophages. Herein, we investigate the regulation of FABP5-IN-1, a FABP5 inhibitor, on various cells of the gut in an inflammatory environment. Our investigations confirmed that FABP5 ameliorates DSS-induced colitis in mice by impeding the differentiation of macrophages into M1 macrophages in vitro and in vivo. Furthermore, following FABP5-IN-1 intervention, we observed a notable restoration of intestinal goblet cells and tuft cells, even under inflammatory conditions. Additionally, FABP5-IN-1 exhibits a protective effect against DSS-induced colitis by promoting the polarization of macrophages towards the M2 phenotype in vivo. In summary, FABP5-IN-1 confers protection against DSS-induced acute colitis through a multifaceted approach, encompassing the reduction of inflammatory macrophage infiltration, macrophage polarization, regulating Th17/Treg cells to play an anti-inflammatory role in IBD. The implications for IBD are underscored by the comprehensive in vivo and in vitro experiments presented in this article, thereby positioning FABP5 as a promising and novel therapeutic target for the treatment of IBD.

[Soil Heavy Metal Contamination, Sources, and Health Risk of Typical Drinking Water Sources in the Suspended Reach of the Lower Yellow River].

With the implementation of ecological protection and a high-quality development strategy in the Yellow River Basin, the environmental conditions around the Yellow River have attracted wide attention from scholars. In this study, the soil of drinking water sources(Heichi and Liuchi) in the typical suspended reach of the lower reaches of the Yellow River was selected as the research object. The geo-accumulation index and pollution load index were used to analyze the pollution characteristics of seven heavy metals(Cr, Ni, Cu, Zn, Cd, Pb, and As), and correlation analysis, principal component analysis, and absolute factor score-multiple linear regression(APCS-MLR) were employed to reveal the sources of soil heavy metals from both qualitative and quantitative perspectives. The health risk assessment model recommended by the United States Environmental Protection Agency(USEPA) was used to analyze the impact of soil heavy metals on human health, and the contribution rate of pollution sources to health risks was analyzed by combining the APCS-MLR model. The results showed that the average values of ω(Cr), ω(Ni), ω(Cu), ω(Zn), ω(Cd), ω(Pb), and ω(As) in the soil around the water source were 60.27, 30.00, 35.14, 77.75, 0.38, 21.74, and 9.70 mg·kg-1, respectively. Except for As, the contents of Cr, Ni, Cu, Zn, Cd, and Pb were higher than the background values of soil elements in the fluvo-aquic soil area of the lower Yellow River, whereas the contents of Cu and Zn in the soil around Liuchi were significantly higher than those in Heichi. Both the geo-accumulation index and the single-factor index showed that the black pond and the willow pond were slightly polluted by heavy metals, and Cd was the main pollution factor. The pollution load index model showed that the number of non-polluted and mildly polluted samples in the study area accounted for 5% and 95% of the total samples, respectively, indicating that the study area was at a mild pollution level. The source apportionment showed that Cr, Ni, Cu, and As were mainly affected by parent materials. The analysis results of the APCS-MLR model showed that the soil pollutants in the study area were mainly from natural sources, traffic sources, agricultural sources, and unknown sources, and their contribution rates were 42.95%, 23.39%, 16.95%, and 16.71%, respectively. The health risk assessment showed that As was the main non-carcinogenic factor, and Ni was the main carcinogenic factor. The non-carcinogenic risk of heavy metals to adults and children was negligible, and there was a tolerable carcinogenic risk to the human body. For both adults and children, the non-carcinogenic and carcinogenic risk contribution rates of the four pollution sources were:natural sources>unknown sources>traffic sources>agricultural sources, among which natural sources contributed the most to non-carcinogenic and carcinogenic risks. Therefore, it is of great significance to study the characteristics, sources, and effects of soil pollution on human health around the water source area of the suspended reach of the lower reaches of the Yellow River, which is of great significance for the protection of water sources and provides theoretical support for the high-quality development of the ecological environment along the Yellow River.

[Pollution Characteristics and Source Analysis of Heavy Metals in Soils in Yellow River Cultural Park Based on APCS-MLR and PMF Receptor Model].

With open spaces and good ecological environments, urban parks have become the first choice for the leisure and entertainment of many people. Therefore, the quality of park soil environments has gradually attracted the extensive attention of scholars. In this study, we take the Yellow River Cultural Park, a typical human disturbance area in the lower reaches of the Yellow River, as the research area to discuss the characteristics and sources of heavy metal pollution in the soil. Thirty-three soil surface samples were collected from the Yellow River Cultural Park, and the contents of seven heavy metals (Cr, Ni, Cu, Zn, Cd, Pb, and As) were determined using an inductively coupled plasma emission spectrometer (ICP-AES) and an inductively coupled plasma mass spectrometer (ICP-MS). The geo-accumulation index and geo-statistics method were used. Meanwhile, the absolute factor analysis-multiple linear regression (APCS-MLR) receptor model and positive matrix factorization (PMF) analysis model were employed to reveal the sources of soil heavy metals. The results showed that the average contents of heavy metals (Cd, Zn, Cu, Pb, and As) in the surface soil of the study area were 4.62, 1.78, 1.41, 1.08, and 1.03 times higher than the background values of soil elements in the tidal soil area of the lower reaches of the Yellow River, respectively. Except for Zn, the contents of other elements were lower than the corresponding values of soil elements in different regions along the Yellow River Basin. Among the seven heavy metal elements, the coefficients of variation of Cd and As were greater than 50%, showing obvious spatial variability. The decreasing trend of the accumulation index of the seven elements was Cd>Zn>Cu>Ni>Pb>As=Cr, and the element Cd belonged to the middle pollution category, which was obviously accumulated in the surface soil. The spatial distribution of heavy metals in the soil differed:the high contents of Cr, Cu, and Ni were distributed in the southwest and northeast, and the high-value areas of Cd and Pb were consistent with the areas of human activity intensity. The high-value areas of Zn and As were located in the center of lacustrine sediments. The combined results of the APCS-MLR and PMF models suggested that the first pollution source of soil heavy metal elements in the Yellow River Cultural Park could have been a natural source, the second pollution source may have been a transportation source, and the third source of pollution was judged as a mixed source. Human activities such as transportation sources and mixed sources were the main sources of heavy metal soil pollution, and Cr, Cu, and Ni were affected by natural factors. The contribution rates of APCS-MLR were 46.67%, 24.11%, 16.12%, and 13.10%, respectively, and the contribution rates of PMF were 35.50%, 35.48%, and 29.02%, respectively. This research can provide a basis for improving the ecological environment quality of the park and improving the health level of the population and can also provide support for the ecological environment risk management and comprehensive management along the Yellow River.

Performance Evaluation and Formation Mechanism of Viscoelastic Surfactant Fracturing Fluids with Moderate Interfacial Activity Enhanced by Janus-SiO2 Nanoparticles.

Nanoparticles (NPs) exhibit great potential to improve various properties of viscoelastic surfactant (VES) fracturing fluids in the development of low-permeability reservoirs. In the present study, the amphiphilic Janus NPs (JANPs) were fabricated via the Pickering emulsion method and employed to construct the novel JA12C (JANPs with dodecyl hydrophobic carbon chains)-assisted VES fracturing fluid (JAVES). The successful fabrication of JANPs was confirmed via Fourier transform infrared spectroscopy (FTIR) measurements and water contact angle tests. The rheology behavior of the VES fracturing fluid incorporating various SiO2 NPs including hydrophilic SiO2 NPs (HLNPs), JA8C (JANPs with octyl hydrophobic carbon chains), and JA12C was systematically investigated. It was revealed that the additional JA12C significantly improved the tolerance and proppant suspension properties. To explore the subsequent oil recovery performance of various gel breaking liquids, the formation wettability and the oil-water interfacial tension (IFT) were studied after the evaluation of breaking properties and formation damage properties of various fracturing fluids. The results suggested that the JAVES gel breaking liquid showed remarkable wettability alternation capability and moderate oil-water IFT reduction ability, which can partially reduce the impact on reservoir permeability. Moreover, the formation mechanism of the JAVES was proposed by molecular dynamics simulations at the molecular level, which was further visually verified via the cryo-TEM images. The improved viscoelasticity of developed the JAVES with moderate interfacial activity is advantageous to enhance subsequent oil recovery.

Circular RNA expression alterations and function prediction in OSA-induced pancreatic injury in mice: New insights into pathogenesis.

OBJECTIVES: Increasing studies have shown that circular RNAs (circRNAs) participate in the pathogenesis and progression of many diseases. However, the function of circRNAs in obstructive sleep apnea (OSA)-induced pancreatic damage has not been fully elucidated. In this study, the altered circRNA profiles in a chronic intermittent hypoxia (CIH) mouse model were investigated, aiming to provide novel clues for delineating the underlying mechanisms of OSA-induced pancreatic injury. METHODS: A CIH mouse model was established. circRNA microarray was then applied to profile circRNA expression in pancreatic samples from CIH groups and controls. Our preliminary findings were validated by qRT-PCR. Subsequently, GO and KEGG pathway analyses were carried out to annotate the biological functions of target genes of circRNAs. Lastly, we constructed a circRNA-miRNA-mRNA (ceRNA) network according to the predicted circRNA-miRNA and miRNA-mRNA pairs. RESULTS: A total of 26 circRNAs were identified to be differentially expressed, with 5 downregulated and 21 upregulated in the CIH model mice. Six selected circRNAs were preliminarily used to confirm the results by qRT-PCR, which were consistent with microarray. GO and pathway analysis indicated that numerous mRNAs were involved in the MAPK signaling pathway. The ceRNA analysis displayed the broad potentials of the dysregulated circRNAs to modulate their target genes by acting as miRNAs sponges. CONCLUSIONS: Taken together, our study first revealed the specific expression profile of circRNAs in CIH-induced pancreatic injury, which suggested a novel focus for investigating the molecular mechanism of OSA-induced pancreatic damage through modulating circRNAs.

CircRNA expression profiles and functional analysis in a mouse model of chronic intermittent hypoxia-induced renal injury: new insight into pathogenesis.

Increasing evidence has demonstrated that circular RNAs (circRNAs) play crucial roles in the pathogenesis of multiple diseases. However, the functions of circRNAs in renal injury induced by obstructive sleep apnea (OSA) are poorly understood. The aim of this current study is to identify the global changes of circRNAs expression in OSA-induced renal damage. The mouse model of OSA treated by chronic intermittent hypoxia (CIH) was established. We assessed the expression profiles of circRNAs in CIH caused renal injury by microarray analysis. Bioinformatic analyses were further performed by us to assess those differentially expressed circRNAs. Quantitative realtime PCR (qRT-PCR) were then conducted to assure the data of microarray. Finally, a circRNA-miRNA -mRNA competing endogenous RNA (ceRNA) regulatory network was constructed. We found 11 upregulated and 13 downregulated circRNAs in CIH-induced renal injury. The qRT-PCR validated that the six selected circRNAs were identical to the results of microarray. Both Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were further employed to annotate the potential functions of dysregulated circRNAs. Finally, we established a ceRNA network to predict the target genes of circRNAs. In general, our results first illustrate that circRNAs are aberrantly expressed in OSA-induced renal injury, which might aid in offering novel genetic insights into this disease and potential therapeutic targets for OSA-associated chronic kidney disease.

Distribution and sources of fluvial pollen in the middle reaches of the Yellow River in China and their relationship with vegetation and land use.

Understanding the processes determining the composition of alluvial pollen assemblages and its relationship with watershed vegetation is a prerequisite for alluvial palynological study. Palynological analysis of a total of 45 river water samples collected from the middle reaches of the Yellow River and its major tributaries, identifies the distribution patterns, possible sources of pollen and relationship with the catchment vegetation. The results reveal that the pollen assemblages in the middle reaches of the Yellow River is dominated by herbaceous taxa, and the pollen is mainly derived from fluvial sources. Higher concentrations of the pollen tend to occur in the southern part of the study area. The Luo River is the main source of tree pollen in the Wei River Basin, while the Sanchuan River and Xinshui River are the main sources of tree pollen in the mainstream of the Yellow River. Herbaceous pollen mainly originates from the flood plain, and from channel bars and point bars, and there is no obvious relationship between herbaceous pollen and tributary inputs. The relative proportions of the various land use classes in the middle reaches of the Yellow River can be ordered as follows: grassland (GL) > cultivated land (CL) > forest (FO) > shrubland (SH) > water (WA). The herbaceous pollen of the Huangfuchuan River and Kuye River are closely related to the coverage of GL; cereal pollen is not fully representative of the CL coverage in the watershed; and the pollen of woody plants is extremely over-represented compared to the coverage of FO and SH in the watershed. Our results provide basic information about the sources of fluvial pollen and its indicative significance in the lower Yellow River and they are also potentially applicable to other major river basins.

A Systematic Analysis of the Correlation between Flavor Active Differential Metabolites and Multiple Bean Ripening Stages of Coffea arabica L.

Coffee cherries contain a crucial flavor-precursor and chemical substances influencing roasted bean quality, yet limited knowledge exists on metabolite changes during cherry ripening. Our study identified 1078 metabolites, revealing 46 core differential metabolites using a KEGG pathway analysis. At the GF vs. ROF stage, amino acid synthesis dominated; ROF vs. BRF featured nucleotide catabolism; BRF vs. PRF exhibited glycoside and flavonoid synthesis; and PRF vs. PBF involved secondary metabolite synthesis and catabolism. The PRF stage emerged as the optimal cherry-harvesting period. A correlation analysis identified core differential metabolites strongly linked to taste indicators, suggesting their potential as taste markers. Notably, nucleotides and derivatives exhibited significant negative correlations with glycosides and flavonoids during ripening. This research systematically analyzed flavor and active substances in green coffee beans during cherry ripening, offering valuable insights into substance formation in Coffea arabica L.

Effect of Fe(III) Species on the Stability of a Water-Model Oil Emulsion with an Anionic Sulfonate Surfactant as an Emulsifier.

The stability of an emulsion has an important effect on enhancing oil recovery. However, the effect of ions with different valences on the stability of the emulsion emulsified by an ionic surfactant is not fully understood. In this study, the effects of Fe(III) species on the stability, microscopic morphology of droplets, interfacial properties, and rheological properties of water-model oil emulsions emulsified by sodium dodecyl benzenesulfonate (SDBS) were explored. The effect of Fe(III) species on the stability of a W/O crude oil emulsion was also explored. The stability experiment results show that the addition of the Fe(III) species impairs the stability of the model oil-in-water (O/W) emulsion, in which the O/W model oil emulsion is inverted to a water-in-model oil (W/O) emulsion at ∼99 ppm. With the increase of Fe(III) species concentration, stable W/O model oil and W/O crude oil emulsions are obtained. The rheological results indicated that the existence of the Fe(III) species has a remarkable effect on the viscosity and viscoelastic behaviors of the water-model oil emulsion. The calculation results based on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory are in accord with the stability experiment results. Furthermore, the addition of EO groups makes the phase inversion point appear at a higher Fe(III) species concentration, forming a more stable W/O model oil emulsion and a more unstable O/W model oil emulsion. The experimental results are helpful to comprehensively understand the effect of Fe(III) species on the stability of an emulsion emulsified by an anionic sulfonate surfactant, which can help to enhance the oil recovery.

Natural variation of GhSI7 increases seed index in cotton.

KEY MESSAGE: qSI07.1, a major QTL for seed index in cotton, was fine-mapped to a 17.45-kb region, and the candidate gene GhSI7 was verified in transgenic plants. Improving production to meet human needs is a vital objective in cotton breeding. The yield-related trait seed index is a complex quantitative trait, but few candidate genes for seed index have been characterized. Here, a major QTL for seed index qSI07.1 was fine-mapped to a 17.45-kb region by linkage analysis and substitutional mapping. Only GhSI7, encoding the transcriptional regulator STERILE APETALA, was contained in the candidate region. Association test and genetic analysis indicated that an 845-bp-deletion in its intron was responsible for the seed index variation. Origin analysis revealed that this variation was unique in Gossypium hirsutum and originated from race accessions. Overexpression of GhSI7 (haplotype 2) significantly increased the seed index and organ size in cotton plants. Our findings provided a diagnostic marker for breeding and selecting cotton varieties with high seed index, and laid a foundation for further studies to understand the molecular mechanism of cotton seed morphogenesis.

Pollution, Ecological Risk and Source Identification of Heavy Metals in Sediments from the Huafei River in the Eastern Suburbs of Kaifeng, China.

Rivers in urban environments are significant components of their ecosystems but remain under threat of pollution from unchecked discharges of industrial sewage and domestic wastewater. Such river pollution, particularly over the longer term involving heavy metals, is an issue of worldwide concern regarding risks to the ecological environment and human health. In this study, we investigate the long-term pollution characteristics of the Huafei River, an important urban river in Kaifeng, China. River sedimentary samples were analyzed, assessing the degree and ecological risk of heavy metal pollution using the geo-accumulation index and potential ecological risk index methods, whilst Pearson's correlation, principal component and cluster analyses were used to identify the sources of pollution. The results show that heavy metal concentrations are significantly higher than their corresponding fluvo-aquic soil background values in China, and the geo-accumulation indexes indicate that of the eight heavy metals identified, Hg is most prevalent, followed in sequence by Cd > Zn > Cu > Pb > Ni > As > Cr. The potential ecological risk index of the Huafei River is very high, with the potential ecological risk intensity highest in the midstream and downstream sections, where it is recommended that pollution control is carried out, especially concerning Hg and Cd. Long-term sequence analysis indicates that Cu and Pb dropped sharply from 1998 to 2017, but rebounded in 2019, and that Zn shows a continuous decreasing trend. Four main sources for the heavy metal contaminants were identified: Cr, Cu, Ni, Pb, Zn and Hg derived mainly from industrial activities, traffic sources and natural sources; Cd originated mainly from industrial and agricultural activities; whilst As was mainly associated with industrial activities. Thus, special attention should be paid to Hg and Cd, and measures must be taken to prevent further anthropogenic influence on heavy metal pollution.

Haze Occurrence Caused by High Gas-to-Particle Conversion in Moisture Air under Low Pollutant Emission in a Megacity of China.

Haze occurred in Zhengzhou, a megacity in the northern China, with the PM2.5 as high as 254 µg m-3 on 25 December 2019, despite the emergency response measure of restriction on the emission of anthropogenic pollutants which was implemented on December 19 for suppressing local air pollution. Air pollutant concentrations, chemical compositions, and the origins of particulate matter with aerodynamic diameter smaller than 2.5 µm (PM2.5) between 5-26 December were investigated to explore the reasons for the haze occurrence. Results show that the haze was caused by efficient SO2-to-suflate and NOx-to-nitrate conversions under high relative humidity (RH) condition. In comparison with the period before the restriction (5-18 December) when the PM2.5 was low, the concentration of PM2.5 during the haze (19-26 December) was 173 µg m-3 on average with 51% contributed by sulfate (31 µg m-3) and nitrate (57 µg m-3). The conversions of SO2-to-sulfate and NOx-to-nitrate efficiently produced sulfate and nitrate although the concentration of the two precursor gases SO2 and NOx was low. The high RH, which was more than 70% and the consequence of artificial water-vapor spreading in the urban air for reducing air pollutants, was the key factor causing the conversion rates to be enlarged in the constriction period. In addition, the last 48 h movement of the air parcels on 19-26 December was stagnant, and the air mass was from surrounding areas within 200 km, indicating weather conditions favoring the accumulation of locally-originated pollutants. Although emergency response measures were implemented, high gas-to-particle conversions in stagnant and moisture circumstances can still cause severe haze in urban air. Since the artificial water-vapor spreading in the urban air was one of the reasons for the high RH, it is likely that the spreading had unexpected side effects in some certain circumstances and needs to be taken into consideration in future studies.