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1.
Materials (Basel) ; 17(12)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38930322

ABSTRACT

High-entropy alloys (HEAs) have garnered significant attention for their exceptional properties, with eutectic high-entropy alloys (EHEAs) emerging as particularly notable due to their incorporation of eutectic structures comprising soft and hard phases. This study investigated the influence of shear strain on the microstructural refinement and mechanical properties of AlCoCrFeNi2.1 EHEAs, which were subjected to high-pressure torsion (HPT) at room temperature under a pressure of 6 GPa across 0.5 to 3 turns, compared to the initial material. After HPT treatment, significant grain refinement occurred due to strong shear strain, evidenced by the absence of B2 phase peaks in X-ray diffraction (XRD) analysis. Microhardness increased substantially post-HPT, reaching a saturation point at approximately 575 HV after three turns, significantly higher than that of the original sample. Moreover, the ultimate tensile strength of HPT-treated specimens reached around 1900 MPa after three revolutions, compared to approximately 1100 MPa for the as-cast alloy, with a mixed fracture mode maintained. This investigation underscores the efficacy of HPT in enhancing the mechanical properties of AlCoCrFeNi2.1 EHEAs through microstructural refinement induced by shear deformation, offering insights into the design and optimization of advanced HEAs for various engineering applications.

2.
Mar Pollut Bull ; 205: 116589, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38875970

ABSTRACT

Airborne bacteria along with chemical composition of aerosols were investigated during five sampling seasons at an offshore island of the East China Sea. Bacterial diversity was the lowest in spring, the highest in winter, and similar between the autumns of 2019 and 2020, suggesting remarkably seasonal variation but little interannual change. Geodermatophilus (Actinobacteria) was the indicator genus of mineral dust (MD) showed higher proportion in spring than in other seasons. Mastigocladopsis_PCC-10914 (Cyanobacteria) as the indicator of sea salt (SS) demonstrated the highest percentages in both autumns, when the air masses mainly passed over the ocean prior to the sampling site. The higher proportions of soil-derived genera Rubellimicrobium and Craurococcus (both Proteobacteria) and extremophile Chroococcidiopsis_SAG_2023 (Cyanobacteria) were found in summer and winter, respectively. Our study explores the linkage between aerosol source and transport path and bacterial composition, which has implication to understanding of land-sea transmission of bacterial taxa.


Subject(s)
Aerosols , Air Microbiology , Bacteria , Environmental Monitoring , Seasons , Aerosols/analysis , China , Biodiversity , Oceans and Seas , Seawater/chemistry , Seawater/microbiology
3.
ACS Appl Mater Interfaces ; 16(9): 11849-11859, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38411114

ABSTRACT

To prepare anion exchange membranes with high water electrolysis and single fuel cell performance, an inorganic-organic composite (IOC) strategy with click cross-linked membranes coated with different contents of hydrophilic polar nanozirconia is proposed to fabricate composite membranes (CM) PBP-SH-Zrx. The performance test results showed that the CM PBP-SH-Zr4 not only has good through-plane ionic conductivity (167.7 mS cm-1, 80 °C), but also exhibits satisfactory dimensional stability (SR 16.5%, WU 206.4%, 80 °C), especially demonstrating excellent alkaline stability with only 16% degradation (2 M NaOH for 2200 h). In water electrolysis, the "microgap" between the membrane and catalyst layer (solid-solid interface) is alleviated, and the membrane electrode assembly (MEA) interfacial compatibility (liquid-solid-solid interface) is enhanced. The CM PBP-SH-Zr4 showed the lowest charge transfer resistance (Rct, 0.037 Ω cm2) and a high current density of 2.5 A cm-2 at 2.2 V, while the voltage drop was 0.361 mV h-1 after 360 h of endurance (six start-stop cycles) at 60 °C and 500 mA cm-2, proving a good water electrolysis durability. Moreover, an acceptable peak power density of 0.464 W cm-2 at 80 °C is achieved in a H2/O2 fuel cell with a PBP-SH-Zr4-AEM. Therefore, the IOC strategy can enhance the membrane's comprehensive performance and interface compatibility of MEA and may promote the development of anion exchange membranes (AEMs) for water electrolysis and fuel cells.

4.
ACS Appl Mater Interfaces ; 16(6): 7894-7903, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38300277

ABSTRACT

A series of SEBS-C6-PIP-yPTP (y = 0-15%) AEMs with good mechanical and chemical stability were prepared by combining the strong rigidity of p-triphenyl, good toughness of SEBS, and excellent stability of PIP cations. After the introduction of a p-triphenyl polymer into the main chain, a clear hydrophilic-hydrophobic phase separation structure was constructed within the membrane, forming a continuous and interconnected ion transport channel to improve ion transport efficiency. Moreover, the molecular chains of the cross-linked AEMs change from chain-like to network-like, and the tighter binding between each molecule increases the tensile strength. The special structure of the six-membered ring makes PIP have a significant constraint effect; when nucleophilic substitution and Hoffman elimination occur at the α and ß positions, the required transition state potential energy increases, making the reaction difficult to occur and improving the alkaline stability of the polymer membrane. The SEBS-C6-PIP-15%PTP membrane has the best mechanical properties (Ts = 38.79 MPa, Eb = 183.09% at 80 °C, 100% RH), the highest ion conductivity (102.02 mS. cm-1 at 80 °C), and the best alkaline stability (6.23% degradation at 80 °C in a 2 M NaOH solution for 1400 h). It can be seen that organic-organic covalent cross-linking is an effective means to improve the comprehensive performance of AEMs.

5.
ACS Appl Mater Interfaces ; 16(6): 7660-7669, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38295432

ABSTRACT

In order to improve the mechanical and water electrolysis performance of anion exchange membranes (AEMs), we adjusted the ratio between p-terphenyl and m-terphenyl to balance the backbone conformation, which gives it a better suitability for a better combination with cations. The results showed that poly(m-terphenyl-co-p-terphenyl)-based AEMs have excellent mechanical properties. Among them, the m-p-TP-40-BOP-ASU membrane has the highest tensile strength and elongation at break (75.72 MPa and 16.07%). The ionic conductivity reaches 137.14 mS cm-1 at 80 °C owing to the fact that efficient ion-conducting channels are formed by well-balanced molecular structures. The current density of the m-p-TP-40-BOP-ASU membrane reached 1.96 A cm-2 (1 M KOH aq, 2.0 V and 60 °C). After testing for 112 h under a current density of 500 mA cm-2, the voltage increased by 102 mV compared to the initial electrolysis voltage. All results have shown that m-p-TP-x-BOP-ASU has excellent electrolysis performance and electrochemical durability and has a promising application prospect in AEM water electrolyzers.

6.
ACS Appl Mater Interfaces ; 16(1): 1394-1403, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38157839

ABSTRACT

The present paper studied the chitosan-doped composite diaphragm by the phase exchange method with the objective of developing a composite diaphragm that complies with the alkaline water electrolysis requirements, as well as tested the electrolytic performance of the diaphragm in alkaline water electrolysis. The structure and morphology are characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The performance of chitosan-doped composite diaphragms was tested; CS3Z12 composite diaphragm with a low area resistance (0.20 Ω cm2), a high bubble point pressure (2.75 bar), and excellent electrochemical performance (current density of 650 mA cm-2 at 1.83 V) shows the best performance. Moreover, the performance of the synthesized composite diaphragm is significantly elevated compared to commercial diaphragms (Zirfon PERL), which is promising for practical application in alkaline electrolytic cells.

7.
Environ Sci Technol ; 57(34): 12741-12751, 2023 08 29.
Article in English | MEDLINE | ID: mdl-37578487

ABSTRACT

Marine biological activities make a non-negligible contribution to atmospheric aerosols, leading to potential impacts on the regional atmospheric environment and climate. The eastern China seas are highly productive with significant emissions of biogenic substances, but the spatiotemporal variations of marine biogenic aerosols are not well known. Air mass exposure to chlorophyll a (AEC) can be used to indicate the influence of biogenic sources on the atmosphere to a certain degree. In this study, the 12 year (2009-2020) daily AEC were calculated over the eastern China seas, showing the spatial and seasonal patterns of marine biogenic influence intensity which were co-controlled by surface phytoplankton biomass and boundary layer height. By combining the AEC values, relevant meteorological parameters, and extensive observations of a typical biogenic secondary aerosol component, methanesulfonate (MSA), a parameterization scheme for MSA simulation was successfully constructed. This AEC-based approach with observation constraints provides a new insight into the distribution of marine biogenic aerosols. Meanwhile, the wintertime air mass retention over land exhibited a significant decrease, showing a decadal weakening trend of terrestrial transport, which is probably related to the weakening of the East Asian winter monsoon. Thus, marine biogenic aerosols may play an increasingly important role in the studied region.


Subject(s)
Air Pollutants , Air Pollutants/analysis , Chlorophyll A , Oceans and Seas , China , Atmosphere/analysis , Seasons , Aerosols/analysis , Environmental Monitoring
8.
ACS Appl Mater Interfaces ; 15(16): 20141-20150, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37058551

ABSTRACT

Metals and their compounds effectively suppress the polysulfide shuttle effect on the cathodes of a lithium-sulfur (Li-S) battery by chemisorbing polysulfides and catalyzing their conversion. However, S fixation on currently available cathode materials is below the requirements of large-scale practical application of this battery type. In this study, perylenequinone was utilized to improve polysulfide chemisorption and conversion on cobalt (Co)-containing Li-S battery cathodes. According to IGMH analysis, the binding energies of DPD and carbon materials as well as polysulfide adsorption were significantly enhanced in the presence of Co. According to in situ Fourier transform infrared spectroscopy, the hydroxyl and carbonyl groups in perylenequinone are able to form O-Li bonds with Li2Sn, facilitating chemisorption and catalytic conversion of polysulfides on metallic Co. The newly prepared cathode material demonstrated superior rate and cycling performances in the Li-S battery. It exhibited an initial discharge capacity of 780 mAh g-1 at 1 C and a minimum capacity decay rate of only 0.041% over 800 cycles. Even with a high S loading, the cathode material maintained an impressive capacity retention rate of 73% after 120 cycles at 0.2 C.

9.
Sci Total Environ ; 875: 162581, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36889406

ABSTRACT

Airborne bacteria may have significant impacts on aerosol properties, public health and ecosystem depending on their taxonomic composition and transport. This study investigated the seasonal and spatial variations of bacterial composition and richness over the east coast of China and the roles of East Asian monsoon played through synchronous sampling and 16S rRNA sequencing analysis of airborne bacteria at Huaniao island of the East China Sea (ECS) and the urban and rural sites of Shanghai. Airborne bacteria showed higher richness over the land sites than Huaniao island with the highest values found in the urban and rural springs associated with the growing plants. For the island, the maximal richness occurred in winter as the result of prevailing terrestrial winds controlled by East Asian winter monsoon. Proteobacteria, Actinobacteria and Cyanobacteria were found to be top three phyla, together accounting for 75 % of total airborne bacteria. Radiation-resistant Deinococcus, Methylobacterium belonging to Rhizobiales (related to vegetation) and Mastigocladopsis_PCC_10914 originating from marine ecosystem were indicator genera for urban, rural and island sites, respectively. The Bray-Curits dissimilarity of taxonomic composition between the island and two land sites was the lowest in winter with the representative genera over island also typically from the soil. Our results reveal that seasonal change of monsoon wind directions evidently affects the richness and taxonomic composition of airborne bacteria in China coastal area. Particularly, prevailing terrestrial winds lead to the dominance of land-derived bacteria over the coastal ECS which may have a potential impact on marine ecosystem.


Subject(s)
Air Microbiology , Bacteria , Ecosystem , Wind , China , Cyanobacteria , RNA, Ribosomal, 16S/genetics , Bacteria/genetics , Bacteria/isolation & purification , Air , Seasons , Environment
10.
J Colloid Interface Sci ; 629(Pt A): 1045-1054, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36154971

ABSTRACT

The development of Li-S battery has been seriously hindered by the shuttle effect of polysulfides and the mechanical instability of the sulfur electrode during cycling. Constructing strong-affinity oxide hosts is an effective way to anchor the polysulfides. And then the oxide hosts with sulfur active materials need additional binder to adhere them to the current collector, and they also possess poor ability to suppress the volume change of sulfur cathode. Herein, a bifunctional lithium polysilicate (Li2O·nSiO2, LSO) as highly efficient adhesion agent and anchoring host has been exploited for long-lifespan Li-S battery. Like other oxide hosts, density functional theory (DFT) calculations reveal that LSO also displays strong chemisorption effect towards polysulfides. Specially, the LSO shows impressive adhesive property and mechanical strength, which make it act as a robust binder to improve the mechanical stability of the sulfur electrode. The sulfur cathode with LSO as the highly efficient adhesion agent and anchoring host can give an excellent cycling stability with âˆ¼ 0.076 % capacity decay per cycle at 0.5C for 500 cycles. This work lights a new way to improve the chemical and mechanical stability of sulfur cathodes.

11.
World J Gastrointest Surg ; 15(12): 2919-2925, 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38222016

ABSTRACT

BACKGROUND: Esophageal atresia (EA) is a life-threatening congenital malformation in newborns, and the traditional repair approaches pose technical challenges and are extremely invasive. Therefore, surgeons have been actively investigating new minimally invasive techniques to address this issue. Magnetic compression anastomosis has been reported in several studies for its potential in repairing EA. In this paper, the primary repair of EA with magnetic compression anastomosis under thoracoscopy was reported. CASE SUMMARY: A full-term male weighing 3500 g was diagnosed with EA gross type C. The magnetic devices used in this procedure consisted of two magnetic rings and several catheters. Tracheoesophageal fistula ligation and two purse strings were performed. The magnetic compression anastomosis was then completed thoracoscopically. After the primary repair, no additional operation was conducted. A patent anastomosis was observed on the 15th day postoperatively, and the magnets were removed on the 23rd day. No leakage existed when the transoral feeding started. CONCLUSION: Thoracoscopic magnetic compression anastomosis may be a promising minimally invasive approach for repairing EA.

12.
ACS Appl Mater Interfaces ; 14(34): 39343-39353, 2022 Aug 31.
Article in English | MEDLINE | ID: mdl-35997247

ABSTRACT

To balance the ionic conductivity and dimensional stability of anion-exchange membranes (AEMs), several cross-linked ether-free poly(terphenyl isatin piperidinium) copolymers were synthesized using 1,2-bis(2-aminoethoxy)ethane as a cross-linker. By introducing an alkyl diamine-based hydrophobic cross-linker as a control, the effects of the dipolar-molecule-containing cross-linker on the comprehensive performance of the membranes were investigated. Cation-dipole interactions between the cations and the hydrophilic ethylene oxide cross-linker enhance the self-assembly capability of the cationic groups. The introduction of the rotatable ethylene oxide cross-linker facilitates the flexibility of the cross-linked networks, thereby promoting hydrophilic/hydrophobic phase separation and inhibiting excessive swelling of the corresponding AEMs simultaneously. The resulting PTPBHIN-O19 membrane showed a high hydroxide conductivity (151.69 mS cm-1) and low swelling ratio (10.53%) at 80 °C. Furthermore, owing to the cross-linked structure and ether-free polymer backbone with high alkali resistance, the membranes treated in 3 M NaOH at 80 °C for 1600 h maintained ≥85% of their hydroxide conductivity, indicating excellent alkaline stability. A H2/O2 fuel cell based on the PTPBHIN-O19 AEM exhibited a maximum power density of 398 mW cm-2 at 515 mA cm-2.

13.
Environ Sci Pollut Res Int ; 29(2): 3051-3061, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34383214

ABSTRACT

Two novel absorbents were synthesized for the first time by banana and pomegranate peels using diethylenetriaminepentaacetic acid (DTPA) modification to eliminate Cd(II) and Ni(II) of sewage. The DTPA-modified peels performed significantly higher adsorption capacity than unmodified materials. The maximum adsorption capacities of DTPA-modified banana/pomegranate peel were 46.729/46.296 mg/g for Cd(II), and 29.240/16.611 mg/g for Ni(II). Adsorption isotherm and kinetics models were simulated to determine their removal efficiency and potential for recovery of these two heavy metals. As the results, the adsorption reached equilibrium within 5 min and was well described by the pseudo-second order model and Langmuir isotherm. The surface morphology analysis of the synthetic materials by Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy, Fourier Transform Infrared spectroscopy, and X-ray Photoelectron Spectroscopy, implied that ion exchange, complexation, and physical adsorption may together contribute to Cd(II) and Ni(II) loading on DTPA-modified peels. This study demonstrates the feasibility of waste peels as cost-efficient bio-absorbents to remove Cd(II) and Ni(II) in sewage systems, and discovers potential adsorption mechanism of efficiency improvements after DTPA modification.


Subject(s)
Musa , Pomegranate , Water Pollutants, Chemical , Adsorption , Cadmium , Hydrogen-Ion Concentration , Kinetics , Pentetic Acid , Spectroscopy, Fourier Transform Infrared , Water Pollutants, Chemical/analysis
14.
Environ Sci Pollut Res Int ; 29(17): 25748-25758, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34846656

ABSTRACT

The treatment of heavy metal (HM) wastewater is a critical and considerable challenge. Fruit peel-based HM adsorption is a promising way for the water pollution control and the reuse of agricultural waste. In this study, a novel adsorbent based on orange peel was synthesized for the first time by introducing abundant -COO groups with ethylenediaminetetraacetic dianhydride (EDTAD) to eliminate Cd(II) and Co(II) of sewage solution. The synthesized adsorbent displayed excellent adsorption capacity of 51.020 and 40.486 mg/g for Cd(II) and Co(II), respectively, and the adsorption equilibrium was achieved within 5 min, following the Langmuir isotherm model and the pseudo-second-order model. Surface characterization of adsorbents by scanning electron microscopy-energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy confirmed that ion exchange, complexation, and physical adsorption could occur during the adsorption process. The rapid and highly efficient adsorption performance suggests EDTAD-modified synthesized orange peel possesses great potential for HM removal from sewage systems.


Subject(s)
Citrus sinensis , Metals, Heavy , Water Pollutants, Chemical , Adsorption , Cadmium/chemistry , Hydrogen-Ion Concentration , Kinetics , Metals, Heavy/chemistry , Sewage , Spectroscopy, Fourier Transform Infrared , Water Pollutants, Chemical/analysis
15.
Appl Microbiol Biotechnol ; 105(16-17): 6369-6379, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34402939

ABSTRACT

Monascus yellow pigments (MYPs), as food colorants, are of great interest to the food industry, because of their beneficial biological activities. In this study, a comparative metabolomics strategy revealed the metabolic regulatory mechanism of MYP overproduction, comparing ammonium chloride with peptone as nitrogen sources. Metabolomics-based multivariate regression modeling showed that metabolic biomarkers/modules, such as glucose, lactate, and the pentose phosphate (PP) pathway, were closely associated with the biosynthesis of MYPs. Exogenous addition of glucose increased production of MYPs, whereas lactate reduced it. Inhibition of the PP pathway with dehydroepiandrosterone decreased MYP production, while increasing the shunting production of orange and red pigments. All these treatments significantly changed the expression profiles of the pigment biosynthetic gene cluster and the mycelial morphology. Overall, this study demonstrates the feasibility of elucidating the mechanism of MYP biosynthesis by comprehensive metabolomics analysis, as well as discovering potential engineering targets of efficiency improvements to commercial MYP production. KEY POINTS: • Comparative metabolomics revealed the biomarkers/modules of MYP production. • A rational exogenously adding strategy was implemented to regulate MYP synthesis. • Expression profiles of gene cluster and mycelial morphology were characterized.


Subject(s)
Monascus , Ammonium Chloride , Metabolomics , Nitrogen , Pigments, Biological
16.
ACS Appl Mater Interfaces ; 13(23): 27085-27095, 2021 Jun 16.
Article in English | MEDLINE | ID: mdl-34080420

ABSTRACT

Aqueous Zn-ion batteries (AZBs) have been considered as one of the most promising large-scale energy storage systems, owing to the advantages of raw material abundance, low cost, and eco-friendliness. However, the severe growth of Zn dendrites leads to poor stability and low Coulombic efficiency of AZBs. Herein, to effectively inhibit the growth of Zn dendrites, a new strategy has been proposed, i.e., tuning the surface energy of the Zn anode. This strategy can be achieved by in situ doping of Sn heteroatoms in the lattice of metallic Zn via codeposition of Sn and Zn with a small amount of the SnCl2 electrolyte additive. Density functional theory calculations have suggested that Sn heteroatom doping can sharply decrease the surface free energy of the Zn anode. As a consequence, driven by the locally strong electric field, metallic Sn tends to deposit at the tips of the Zn anode, thus decreases the surface energy and growth of Zn at the tips, resulting in a dendrite-free Zn anode. The positive effect of the SnCl2 additive has been demonstrated in both the Zn∥Zn symmetric battery and the Zn/LFP and Zn/HATN full cell. This novel strategy can light a new way to suppress Zn dendrites for long life span Zn-ion batteries.

17.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(6): 563-568, 2021 Jun.
Article in Chinese | MEDLINE | ID: mdl-34130776

ABSTRACT

OBJECTIVE: To study the association of neonatal blood calcium levels with perinatal factors and neonatal urinary calcium levels measured by an intelligent urine test system. METHODS: The medical data of 96 full-term singleton neonates with mild diseases were collected by a cross-sectional survey, who were hospitalized in the Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, from June to August 2018. Urinary calcium levels measured by an intelligent urine test system, total blood calcium levels, ionized calcium levels, and the mother's calcium and vitamin D supplementation during pregnancy were recorded. RESULTS: Compared with the group without vitamin D supplementation for the mother (17 neonates), the group with vitamin D supplementation for the mother (79 neonates) had significantly higher levels of total blood calcium and ionized calcium (P < 0.05).The group with both vitamin D and calcium supplementation for the mother (68 neonates) had significantly higher levels of ionized calcium than controls (28 neonate) (P=0.05). There was no significant difference in the levels of total blood calcium and ionized calcium between the group with calcium supplementation for the mother (74 neonates) and the group without calcium supplementation for the mother (22 neonates) (P > 0.05). The hypothermia group (5 neonates) had a significantly lower level of total blood calcium than the normal body temperature group (91 neonates) (P < 0.05). There was a significantly positive correlation between the maternal blood total calcium level and the neonatal blood total calcium and ionized calcium levels (r=0.881 and 0.703 respectively; P < 0.05). The neonatal urinary calcium level measured by the intelligent urine test system was significantly correlated with the blood ionized calcium level (r=0.526, P=0.025). CONCLUSIONS: Vitamin D supplementation during pregnancy can increase the blood levels of total calcium and ionized calcium in neonates, and calcium supplementation alone cannot increase the blood levels of total calcium or ionized calcium in neonates. Hypothermia in neonates might cause the reduction in blood calcium levels. The urinary calcium level measured by the intelligent urine test system is positively correlated with the blood level of ionized calcium.


Subject(s)
Calcium , Vitamin D Deficiency , Calcium, Dietary , Cross-Sectional Studies , Female , Humans , Infant, Newborn , Pregnancy , Vitamin D
18.
Sci Total Environ ; 753: 141961, 2021 Jan 20.
Article in English | MEDLINE | ID: mdl-32889319

ABSTRACT

Nutrient stoichiometry and input of trace metals may profoundly affect the growth and community structure of phytoplankton. A bioassay experiment was designed to explore the key components in atmospheric deposition that affect marine phytoplankton growth by adding aerosols and analogues nutrients and Cu to the surface water of the coastal East China Sea (ECS). Our results showed that atmospheric deposition along with the input of phosphate could largely enhance the chlorophyll a (Chl a) concentrations in this eutrophic water. Phosphorus addition lifted the proportions of T. oceanica in Diatoms and B. brevisulcata in Dinoflagellates. T. oceanica replaced S. costatum and became the dominant diatom species after the Chl a peak, probably associated with the N/P ratio approaching to 16. Atmospheric aerosols containing affluent N and little P showed limited promotion to Chl a, and the positive effect was very likely due to the soluble Cu and other trace metals supplied by the aerosol. Moreover, soluble aerosol Cu was found to be conducive to the relative abundance of most dominant class Coscinodiscophyceae, and both soluble aerosol Fe and Cu seemed to be very important for increasing the proportion of S. costatum. Soluble metals could be the key components in aerosols controlling the phytoplankton composition in the eutrophic sea and such impact might exceed affluent P provided by other exogenous sources.


Subject(s)
Diatoms , Phytoplankton , Aerosols/analysis , China , Chlorophyll A
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(5): 441-445, 2020 May.
Article in Chinese | MEDLINE | ID: mdl-32434638

ABSTRACT

OBJECTIVE: To compare intranasal midazolam and intramuscular phenobarbital sodium for their sedative effect in neonates undergoing magnetic resonance imaging (MRI). METHODS: A total of 70 neonates who underwent cranial MRI from September 2017 to March 2019 were randomized into an observation group and a control group, with 35 cases in each group. The observation group received intranasal drops of midazolam (0.3 mg/kg), and the control group received intramuscular injection of phenobarbital sodium (10 mg/kg). The sedation status of the neonates was evaluated using the Ramsay Sedation Scale. Meanwhile, the two groups were compared for the success rate of MRI procedure and incidence of adverse reactions. RESULTS: In the observation group, the sedation score was the highest at 20 minutes post administration, then was gradually decreasing, and decreased to the lowest level at 70 minutes post administration. In the control group, the sedation score was the lowest at 10 minutes post administration, then was gradually increasing, and increased to the highest level at 40 minutes and 50 minutes post administration, followed by a gradual decrease. Comparison of the sedation score at each time period suggested that the sedation score was significantly higher in the observation group than in the control group within 40 minutes post administration (P<0.05), while there were no significant differences between the two groups in the sedation score after 40 minutes post administration (P>0.05). The success rate of MRI procedure was significantly higher in the observation group than in the control group (89% vs 69%, P<0.05). There was no significant difference between the two groups in the incidence of adverse reactions (P>0.05). CONCLUSIONS: Intranasal midazolam is superior to intramuscular phenobarbital sodium in the sedative effect in neonates undergoing MRI, with the benefits of being fast, convenient, safe, and effective.


Subject(s)
Hypnotics and Sedatives/pharmacology , Humans , Infant, Newborn , Magnetic Resonance Spectroscopy , Midazolam , Prospective Studies , Single-Blind Method
20.
Int J Biol Macromol ; 158: 562-568, 2020 May 04.
Article in English | MEDLINE | ID: mdl-32380112

ABSTRACT

Neonatal hypoxic-ischemic encephalopathy (HIE) is a complex condition that remains the leading cause of mortality and morbidity among infants. Polysaccharide has been reported to possess diverse biological activities, however, the neuro-protective activity of polysaccharide isolated from Lycium ruthenicum remains unknown so far. However, the role of Lycium ruthenicum polysaccharide 3 (LRP3) in HIE has not been evaluated. Herein, we investigated the effect of LRP3 on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced primary cortical neurons. Our results demonstrated that LRP3 significantly improved the cell viability of OGD/R-induced cortical neurons. The OGD/R-caused increase in ROS production and decrease in the activities of anti-oxidative enzymes including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were mitigated by LRP3. Besides, the caspase-3 activity in OGD/R-induced cortical neurons was markedly decreased after LRP3 treatment. The increased bax expression and decreased bcl-2 expression caused by OGD/R stimulation were alleviated by pretreatment with LRP3. In addition, LRP3 significantly induced the expressions of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1) in OGD/R-induced cortical neurons. However, inhibition of Nrf2/HO-1 signaling pathway through transfection with siRNA targeting Nrf2 reversed the protective effects of LRP3. In conclusion, LRP3 exerts a neuroprotective effect against OGD/R-induced neuronal injury in rat primary cortical neurons.

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