Hydro-meteorological factors and inflowing nutrients drive water quality in an impounded lake of China's South-to-North Water Diversion Project.

Freshwater lakes play a vital role in global hydrological and biogeochemical cycles, serving various functions and maintaining ecological balance. However, freshwater resources are more vulnerable to deterioration due to multiple stressors. Gaoyou Lake is one of the impounded lakes of the Eastern route of South-to-North Water Diversion Project in China, and as an important source of drinking water, the lake has been routinely monitored. Long-term monitoring of water quality in Gaoyou Lake showed that concentrations of nutrients and chlorophyll a as well as trophic state in the water column increased while water transparency decreased, indicating that the water quality has declined during the last 12 years. Specifically, there was a notable and statistically significant increase in chlorophyll a concentrations, averaging an annual rate of 9.9%. Despite a slight decline in trophic level index until 2014, subsequent years saw an upward trend, ranging from 50.7 to 56.4 and indicating a light eutrophic state. Spatially, the western area displayed higher nutrient and chlorophyll a concentrations. Changes in hydro-meteorological variables and nutrients from inflowing rivers were the main factors correlated with water quality in Gaoyou Lake. Thus, pollution source apportionment and management within Huaihe River basin should be considered to reduce the external loadings of nutrients in order to improve and sustain long-term water quality.

Efficient Construction of pH-Stimuli-Responsive Colloidosomes with High Encapsulation Efficiency.

Intelligent responsive colloidosomes have attracted increasing attention for their potential to enhance the efficacy and decrease the side effects of drugs in biomedical applications. However, a low encapsulation efficiency and complicated preparation method greatly limit their development. Herein, we report an efficient approach for the construction of pH-stimuli-responsive colloidosomes with high encapsulation efficiency by a high-gravity technology. The conditions under which latex particles with different methacrylic acid contents can successfully self-assemble into colloidosomes are explored. During the preparation process, emulsions emulsified for only 10 min at 2500 rpm in a unique high-gravity shearing surroundings are clarified owing to the greatly enhanced micromixing, while the emulsions emulsified for 30 min by a traditional high-speed shear machine at 4000 rpm are still yellow-white. More importantly, regular spherical colloidosomes encapsulating an anticancer drug doxorubicin not only achieve a small mean diameter of 2.82 µm but also realize a high encapsulation efficiency of 76.5%. The release performance of doxorubicin has an obvious pH-stimuli-responsive regularity and follows the first-order model of sustained release. The construction of intelligent responsive colloidosomes as drug carriers provides a route for controlled drug release and biomedical applications.

Greatly Intensified Guest Exchange Strategy for Highly-Efficient Activation of Metal-Organic Frameworks.

The preservation and accessibility of pores are prerequisites to the application of metal-organic frameworks (MOFs). Activation is a key step to eliciting rich features of pores, but it needs a repeated solvent-exchange process which is tedious and time/cost-consuming. Herein, a facile strategy for highly-efficient activation of MOFs utilizing rotating packed bed is proposed. With the tremendous enhancement of molecular mixing and mass transfer in high-gravity and strong-shearing surrounding, nine representative MOFs are completely activated within 2 h without structural change. Compared with conventional process, this activation displays surprising efficiency by accelerating the diffusion of solvents and redissolution of residual reactants in the pores. The complete activation time can be significantly shortened by over 90%. As a proof-of-concept, the methane storage of as-activated UiO-66 is five times that of as-synthesized UiO-66. This strategy provides a potential platform with industrial worth for the activation of MOF materials with ultra-high efficiency and versatility.

Stereoselective synthesis of α-glucosides with glucosyl (Z)-Ynenoates as donors.

A SPhosAuNTf2-promoted DMF-modulated glycosylation approach with glycosyl (Z)-ynenoates as donors was developed for highly α-selective synthesis of various linkage types of α-glucans. The substituent groups were also found to play a significant role in the α-selective glucosylation reactions. The glycosylation approach was effectively applied to the stereospecific synthesis of the α-1,6-linked triglucoside.

Three-Fluid Nozzle Spray Drying Strategy for Efficient Fabrication of Functional Colloidosomes.

Colloidosomes as Pickering emulsion microcapsules are expected to serve various applications, including encapsulation of drugs and loading of functional materials. Normally, when using colloidosomes for drug encapsulation, the latex particles as shell materials need to be mixed with drugs before the assembly process. However, this procedure may cause aggregation of latex particles, thereby resulting in disordered assembled shells or a low loading efficiency. Herein, we propose a three-fluid nozzle spray drying process to efficiently assemble latex particles of P(styrene (St)-co-butyl acrylate (BA)) into colloidosomes. The three-fluid nozzle spray drying equipment allows for the preparation for drug encapsulation without advance mixing of drug and shell materials. This strategy enables the construction of colloidosomes with uniform and controllable pores and the loading of functional materials. The effects of the compressed air flow rate, inlet temperature, feed rate, and solid content were explored, revealing the formation mechanism of colloidosomes during the spray drying process. Doxycycline hydrochloride (DH) was encapsulated in colloidosomes for controllable release, and the sustained release time is up to 100 h. The release rate can be adjusted by varying the glass transition temperature (Tg) and size of latex particles. Furthermore, Fe3O4 nanoparticle (NP)-loaded colloidosomes were constructed by this strategy. The magnetic response intensity of colloidosomes can be modulated by varying the amount of Fe3O4 NPs. The anticancer drug encapsulation and loading of other functional particles were also explored to expand applications.

Synthesis of Nucleosides and Deoxynucleosides via Gold(I)-Catalyzed N-Glycosylation of Glycosyl (Z)-Ynenoates.

Nucleoside analogues are widely used as anticancer and antiviral drugs. Here, we develop a highly efficient gold(I)-catalyzed N-glycosylation approach for versatile synthesis of various types of nucleosides and deoxynucleosides with glycosyl (Z)-ynenoates as donors. The wide scope of the N-glycosylation approach was demonstrated by the synthesis of 31 pyrimidine nucleosides and 8 purine nucleosides. Remarkably, the gold(I)-catalyzed N-glycosylation of pyranosyl (Z)-ynenoates with purines was found to be very effective for regioselective synthesis of pyranosyl N9 purine nucleosides. Based on the catalytic N-glycosylation approach, convenient synthesis of two 5'-deoxynucleosides drugs (capecitabine and galocitabine), four 2'-deoxynucleoside drugs (floxuridine, trifluridine, decitabine and cladribine), four 3',5'-dideoxynucleoside analogues, and four 2',5'-dideoxynucleoside analogues was achieved in a collective manner.

Cr3X4 (X = Se, Te) monolayers as a new platform to realize robust spin filters, spin diodes and spin valves.

Two-dimensional ferromagnetic (FM) half-metals are promising candidates for advanced spintronic devices with small size and high capacity. Motivated by a recent report on controlling the synthesis of FM Cr3Te4 nanosheets, herein, to explore their potential application in spintronics, we designed spintronic devices based on Cr3X4 (X = Se, Te) monolayers and investigated their spin transport properties. We found that the Cr3Te4 monolayer based device shows spin filtering and a dual-spin diode effect when applying a bias voltage, while the Cr3Se4 monolayer is an excellent platform to realize a spin valve. These different transport properties are primarily ascribed to the semiconducting spin channel, which is close to and away from the Fermi level in Cr3Te4 and Cr3Se4 monolayers, respectively. Interestingly, the current in the Cr3Se4 monolayer based device also displays a negative differential resistance effect (NDRE) and a high magnetoresistance ratio (up to 2 × 103). Moreover, we found a thermally induced spin filtering effect and a NDRE at the Cr3Se4 junction under a temperature gradient instead of a bias voltage. These theoretical findings highlight the potential of Cr3X4 (X = Se, Te) monolayers in spintronic applications and put forward realistic materials to realize nanoscale spintronic devices.

Determining heavy metal pollution in sediments from the largest impounded lake in the eastern route of China's South-to-North Water Diversion Project: Ecological risks, sources, and implications for lake management.

The eastern route of the South-to-North Water Diversion Project (ER-SNWDP) is a major human health project designed to alleviate the water scarcity in the Beijing-Tianjin-Hebei region in China. Impounded lake water security is directly related to the water diversion project effectiveness. At present, there is not a thorough understanding of the sediment heavy metals in Lake Hongze, the largest impounded lake of the ER-SNWDP. Consequently, this study reports a distribution analysis of Cu, Zn, Pb, Cr, Cd, As, Hg, and Ni in 101 sediment samples from Lake Hongze; we, utilized the enrichment factor, geoaccumulation index, and potential ecological risk index for the are to determine the ecological risk of heavy metals. The heavy metal source was examined with correlation analysis and principal component analysis-multiple linear regressions. The results showed that the average heavy metal content (Cu, Zn, Pb, Cr, Cd, As, Hg, Ni) were 0.03-1.57 times greater than the Jiangsu Province background values. Cd, As, and Hg were the main contributors to the Lake Hongze ecological risk. Spatially, the open water area was the most polluted among the four lake parts, and most of the flushing area had a low ecological risk. Chengzi bay and the western lake area have similar risk profiles, but are lower than the open water area risk. Source analysis showed that nonpoint-source agricultural pollution and industrial production were important pollution sources, while a considerable portion of the heavy metal content came from atmospheric deposition and natural sources. This study identified the main contamination areas and revealed the possible sources of each heavy metal; as such, this study can serve as a reference for the remediation and management of Lake Hongze to ensure the water safety of the ER-SNWDP.

The impact and mechanisms of the Shanghai pilot free-trade zone on the green total factor productivity of the Yangtze River Delta Urban Agglomeration.

Free-trade zones are highlands of regional development that have a radiating effect on surrounding cities. This paper uses Yangtze River Delta Urban Agglomeration (YRDUA) data from 2003 to 2018, to examine the impact of the China (Shanghai) pilot free-trade zone (SPFTZ) on green total factor productivity (GTFP) in the YRDUA. It uses the regression discontinuity (RD) method and analyzes the influence mechanism with the help of the mediating effect model. The paper presents the following major findings. The establishment of the SPFTZ significantly promoted GTFP in the YRDUA, with technological progress being the main driving force. An analysis using the mediating effect model found that financial efficiency and industrial structure upgrading play a complete mediating role in GTFP growth in the YRDUA. Therefore, the SPFTZ should make use of its policy advantages, take full advantage of the effect of the green growth pole, and promote green mutual development with the YRDUA.

Promising Thermoelectric Performance in Two-Dimensional Semiconducting Boron Monolayer.

A heavy element is a special character for high thermoelectric performance since it generally guarantees a low lattice thermal conductivity. Here, we unexpectedly found a promising thermoelectric performance in a two-dimensional semiconducting monolayer consisting of a light boron element. Using first-principles combined with the Boltzmann transport theory, we have shown that in contrast to graphene or black phosphorus, the boron monolayer has a low lattice thermal conductivity arising from its complex crystal of hexagonal vacancies. The conduction band with an intrinsic camelback shape leads to the high DOS and a high n-type Seebeck coefficient, while the highly degenerate valence band along with the small hole effective mass contributes to the high p-type power factor. As a result, we obtained the p-type thermoelectric figure of merit up to 0.96 at 300 K, indicating that the boron monolayer is a promising p-type thermoelectric material.

NIS/TMSOTf-Promoted Glycosidation of Glycosyl ortho-Hexynylbenzoates for Versatile Synthesis of O-Glycosides and Nucleosides.

Glycosidation plays a pivotal role in the synthesis of O-glycosides and nucleosides that mediate a diverse range of biological processes. However, efficient glycosidation approach for the synthesis of both O-glycosides and nucleosides remains challenging in terms of glycosidation yields, mild reaction conditions, readily available glycosyl donors, and cheap promoters. Here, we report a versatile N-iodosuccinimide/trimethylsilyl triflate (NIS/TMSOTf)-promoted glycosidation approach with glycosyl ortho-hexynylbenzoates as donors for the highly efficient synthesis of O-glycosides and nucleosides. The glycosidation approach highlights the merits of mild reaction conditions, cheap promoters, extremely wide substrate scope, and good to excellent yields. Notably, the glycosidation approach performs very well in the construction of a series of challenging O- and N-glycosidic linkages. The glycosidation approach is then applied to the efficient synthesis of oligosaccharides via the one-pot strategy and the stepwise strategy. On the basis of the isolation and characterization of the departure species derived from the leaving group, a plausible mechanism of NIS/TMSOTf-promoted glycosidation of glycosyl ortho-hexynylbenzoates is proposed.

Association between serum uric acid level and endothelial dysfunction in elderly individuals with untreated mild hypertension.

BACKGROUND: Endothelial dysfunction is the initial stage in atherosclerotic formation and progression and is associated with high serum uric acid (SUA) level. We hypothesized that reactive hyperemia index (RHI), which reflects endothelial function, is associated with SUA levels in elderly individuals with untreated mild hypertension. METHODS: We recruited 123 patients ≥ 60 years with untreated mild hypertension. The association between SUA level and RHI was analyzed using univariate correlation analysis and multiple regression analysis. The receiver operating characteristic (ROC) curve was performed to validate the cutoff value of SUA that can be used to predict endothelial dysfunction. RESULTS: The serum uric acid level significantly increased in the RHI < 1.67 group, and this result was still observed in the subgroup of men. RHI was inversely associated with SUA level (P = 0.006) and the association was still observed after adjusting for factors, such as age, sex, smoking status, and creatinine level (P = 0.014). In the subgroup analysis, a positive association was observed only in men. In the ROC curve analysis, the optimal cutoff values of SUA for predicting endothelial dysfunction was 293.5 µmol/L in elderly mild hypertension patients and 287.0 µmol/L in men. CONCLUSION: A high SUA level was considered an independent predictor of endothelial dysfunction among elderly individuals, particularly men with untreated mild hypertension.

Gold(I)-Catalyzed Glycosylation with Glycosyl Ynenoates as Donors.

A simple and versatile glycosylation method with both armed and disarmed glycosyl ynenoates as donors is developed. Employing a gold(I) complex as catalyst with or without the assistance of TfOH, the scope of the present glycosylation protocol is very wide. The utility of the present ynenoate donors is demonstrated in the efficient synthesis of oligosaccharides via the latent-active strategy and the multiple orthogonal one-pot strategy. Finally, this approach enables the formal synthesis of the tetrasaccharide hapten of Streptococcus pneumoniae serotype 3 and the highly convergent synthesis of the 32mer polymannoside.

Gold(I)-Catalyzed Intermolecular Rearrangement Reaction of Glycosyl Alkynoic ß-Ketoesters for the Synthesis of 4-O-Glycosylated 2-Pyrones.

A new gold(I)-catalyzed rearrangement reaction with glycosyl alkynoic ß-ketoesters as substrates is developed. The rearrangement reactions under the catalysis of PPh3AuOTf proceeded smoothly to afford a range of 4-O-glycosylated 2-pyrones. Based on the isolation of the 4-hydroxy-2-pyrone derivative generated from the departure of the leaving group and the competitive reaction, a plausible mechanism of the gold(I)-catalyzed intermolecular rearrangement reactions is proposed.

Changes in element accumulation, phenolic metabolism, and antioxidative enzyme activities in the red-skin roots of Panax ginseng.

BACKGROUND: Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). METHODS: To explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate-glutathione cycle were examined using conventional methods. RESULTS: Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of H2O2 and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of l-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione-S-transferase activity remained constant. CONCLUSION: Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate-glutathione cycles, are activated to protect against phenolic compound oxidation.

Associations between human aldosterone synthase CYP11B2 (-344T/C) gene polymorphism and antihypertensive response to valsartan in Chinese patients with essential hypertension.

Aldosterone synthase is a mitochondrial enzyme that catalyzes the conversion of 11-deoxycorticosterone to the potent mineralocorticoid aldosterone. The gene encoding aldosterone synthase, CYP11B2, is associated with essential hypertension. But if the genetic variations in aldosterone synthesis could influence the antihypertensive response to Valsartan is not clear. A Chinese sample of 502 persons (217 women) was studied, which was divided into the hypertensive group (EH) of 345 persons and the normotensive group (NB) of 157 persons. Subjects were genotyped through the use of the polymerase chain reaction for the diallelic polymorphisms in CYP11B2. 98 persons of the essential hypertension group received 4 weeks therapy with valsartan. Blood pressure, 24-hour ambulatory blood pressure, biochemical index were also determined. The frequency of CC+CT genotypes in hypertensive group was significantly higher than that in normotensive group (P<0.05), the frequency of C allele of gene CYP11B2 (-344T/C) in hypertensive group was significantly higher than that in normotensive group (P<0.01). The descending values of SBP (systolic blood pressure), DBP (diastolic blood pressure), MAP (mean arterial pressure), 24 h SBP (mean SBP of 24 hours), 24 h DBP (mean DBP of 24 hours), 24 h MAP (mean arterial pressure of 24 hours) of CC+CT genotype group were significantly higher than those of the TT genotype group (P<0.05). The aldosterone synthase CYP11B2 (-344T/C) gene polymorphism is associated with essential hypertension in Chinese. And the aldosterone synthase CYP11B2 (-344T/C) gene polymorphism may be the predictor of the antihypertensive response to Valsartan.

Association of epithelial sodium channel ß-subunit common polymorphism with essential hypertension families in a Chinese population.

The purpose of this study was to investigate whether common polymorphisms in the C-terminus of SCNN1B gene encoding the ß-subunit of epithelial sodium channel are associated with essential hypertension (EH) in Chinese hypertensive families. A total of 433 subjects from 102 EH families were recruited. Biochemical and anthropometric indices and systematic screening of the C-terminus of SCNN1B were performed. Four single nucleotide polymorphisms (SNPs) were found. Homozygotes for the common A allele at rs3743966 had on average a 12.06 mmHg higher SBP and a 7.43 mmHg higher DBP than homozygotes for the rarer T allele. AA + AT genotype of rs3743966 was also found to maybe a risk factor of hypertension by logistic regression and transmission/disequilibrium test. AA + AT genotype of rs3743966 maybe a risk factor of EH. In conclusion, there was a significant association between the rs3743966 SNP in intron 12 and EH in Chinese hypertensive families.

Relationship between the red cell distribution width and the one-year outcomes in Chinese patients with stable angina pectoris.

OBJECTIVE: This study was undertaken to determine the relationship between the red cell distribution width (RDW) and the one year outcomes in Chinese patients with stable angina pectoris. METHODS: A total of 1,442 patients with stable angina pectoris on admission were divided into four groups according to quartiles of the baseline RDW. The relationships between the RDW and one-year cardiac mortality as well as the incidence of acute coronary syndrome (ACS) were assessed. RESULTS: Higher RDW values were associated with an increased one-year cardiac mortality (quartile 1: 0.51%; quartile 2: 0.56%; quartile 3: 0.86%; quartile 4: 2.27%; p<0.001) and one-year ACS (quartile 1: 1.55%; quartile 2: 1.96%; quartile 3: 2.89%; quartile 4: 3.70%; p<0.001). A logistic regression analysis revealed that the RDW independently predicted cardiac mortality (OR: 1.544, 95% CI: 1.058-3.216, p<0.001) and ACS (OR: 1.861, 95% CI: 1.226-3.487, p<0.001) during a one-year follow-up in patients with stable angina pectoris. CONCLUSION: The present study indicates that an elevated RDW value is associated with an increased risk of one-year adverse outcomes in patients with stable angina pectoris.

Interleukin-6, but not soluble adhesion molecules, predicts a subsequent mortality from cardiovascular disease in patients with acute ST-segment elevation myocardial infarction.

Inflammatory responses are an important element in the atherosclerotic process. Therefore, inflammatory markers can potentially serve as predictors of cardiovascular risk. However, the existing data are limited and controversial. We conducted a prospective cohort study with 263 patients with first acute ST-segment elevation myocardial infarction (STEMI) who were admitted to our Hospital within 6 h after the symptoms onset. Clinical data were recorded and serum admission levels of interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble P-selectin (sP-selectin) were determined. The patients were then followed up for 3 years to document cardiovascular mortality. During the follow-up, 34 patients died from cardiovascular causes. The admission levels of IL-6 were significantly higher in these patients, whereas sICAM-1, sVCAM-1, and sP-selectin were comparable between these and the survived patients. The Kaplan-Meier plots revealed a significant increase in cardiovascular mortality with increasing levels of IL-6 (P = 0.0002, χ(2) test). The logistic regression analysis indicated that IL-6 was an independent predictor for cardiovascular mortality. To conclude, our findings indicate that elevated admission levels of IL-6, but not soluble adhesion molecules, provide valuable information for risk assessment of long-term cardiovascular mortality in patients with STEMI.

[Investigation and analysis of the prevalence and risk factors for impaired fasting glucose in outpatients with essential hypertension].

OBJECTIVE: To evaluate the prevalence of impaired fasting glucose (IFG) in outpatients with essential hypertension and the influencing factors. METHODS: 1026 essential hypertensive outpatients aged 15 - 87 years [531 males and 495 females, mean age (51.6 +/- 12.5) years] who visited Xuanwu hospital between February 2004 and January 2007 were recruited in the study. Their medical history, blood pressure, height, weight, waist circumferences (WC), hip circumference (HC), fasting plasma glucose (FPG), TC, TG, LDL-C, HDL-C were detected and analyzed. RESULTS: The abnormal rate of FPG in hypertensive outpatients was 38.5% and incidence of IFG was 30.5%. The differences of gender, systolic blood pressure, BMI, waist-to-hip ratio (WHR), TG, TC between the normal glucose group and the IFG group were significant. Gender, family history of diabetes mellitus, TC and LDL-C enter into the logistic regression model (P < 0.05). CONCLUSIONS: The detection rate of IFG is high in hypertensive outpatients and it is related with gender, family history of diabetes mellitus and disorders of lipid metabolism.