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1.
J Environ Pathol Toxicol Oncol ; 43(4): 43-52, 2024.
Article in English | MEDLINE | ID: mdl-39016140

ABSTRACT

Gastric cancer, a prevalent malady within the digestive tract, has a complex pathological mechanism and numerous patients. The regulation of gastric cancer process by long non-coding RNA (lncRNA) presented new prospects for the study of its molecular mechanism and the treatment of patients. The abnormal expressed genes in gastric cancer were screened by GSE193109 dataset. The correlation between LINC01278 and the likelihood of survival in patients suffering from gastric cancer was investigated by Kaplan-Meier survival curve and multivariate Cox analysis. LINC01278 in gastric cancer tissue samples and cells was verified via RT-qPCR. The cell counting kit-8 (CCK-8) and transwell assay were selected to detect the growth activity of gastric cancer cells. The association between LINC01278 and miR-129-5p was validated through luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay. Correlation analysis of clinical features revealed an association between LINC01278 and the prognosis in gastric cancer patients. LINC01278 was actively expressed in gastric cancer, which exerts a tumor-promoting effect. Silencing LINC01278 suppressed the biological function of tumor cells through spongiform miR-129-5p. LINC01278 has the potential to serve as a novel biomarker, offering new avenues of research for the prognosis and treatment of gastric cancer.


Subject(s)
MicroRNAs , RNA, Long Noncoding , Stomach Neoplasms , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Humans , RNA, Long Noncoding/genetics , MicroRNAs/genetics , Prognosis , Cell Line, Tumor , Female , Male , Gene Expression Regulation, Neoplastic , Middle Aged
2.
Article in English | MEDLINE | ID: mdl-39002060

ABSTRACT

Duck viral hepatitis, primarily caused by duck hepatitis A virus type 1 (DHAV-1), poses a significant threat to the global duck industry. Bacillus subtilis is commonly utilized as a safe probiotic in the development of mucosal vaccines. In this study, a recombinant strain of B. subtilis, designated as B. subtilis RV, was constructed to display the DHAV-1 capsid protein VP1 on its spore surface using the outer coat protein B as an anchoring agent. The immunogenicity of this recombinant strain was evaluated in a mouse model through mixed feeding immunization. The results indicated that B. subtilis RV could elicit specific systemic and mucosal immune responses in mice, as evidenced by the high levels of serum IgG, intestinal secretory IgA, and potent virus-neutralizing antibodies produced. Furthermore, the recombinant strain significantly upregulated the expression levels of IL-2, IL-6, IL-10, TNF-α, and IFN-γ in the intestinal mucosa. Thus, the recombinant strain maintained the balance of the Th1/Th2 immune response and demonstrated an excellent mucosal immune adjuvant function. In summary, this study suggests that B. subtilis RV can be a novel alternative for effectively controlling DHAV-1 infection as a vaccine-based feed additive.

3.
BMC Cardiovasc Disord ; 24(1): 357, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39003444

ABSTRACT

BACKGROUND: The epidemiological distribution of functional mitral regurgitation (FMR) in heart failure (HF) and mildly reduced ejection fraction (HFmrEF) patients and its impact on outcomes remains unclear. We attempt to investigate the prognosis of FMR in patients with HFmrEF. METHODS: The HF center registry study is a prospective, single, observational study conducted at the Second Affiliated Hospital of Shenzhen University, where 2330 patients with acute HF (AHF) were enrolled and 890 HFmrEF patients were included in the analysis. The patients were stratified into three categories based on the severity of FMR: none/mild, moderate, and moderate-to-severe/severe groups. Subsequently, a comparison of the clinical characteristics among these groups was conducted, along with an assessment of the incidence of the primary endpoint (comprising all-cause mortality and readmission for HF) during a one-year follow-up period. RESULTS: The one-year follow-up results indicated that the primary composite endpoint occurrence rates in the three groups were 23.5%, 32.9%, and 36.5%, respectively. The all-cause mortality rates in the three groups were 9.3%, 13.7%, and 16.4% respectively. Survival analysis demonstrated a statistically significant difference in the occurrence rates of the primary composite endpoint and all-cause mortality among the three groups (P < 0.05). Multifactor Cox regression revealed that moderate FMR and moderate-to-severe/severe FMR were independent risk factors for adverse clinical prognosis in HFmrEF patients, with hazard ratios and 95% confidence intervals of 1.382 (1.020-1.872, P = 0.037) and 1.546 (1.092-2.190, P = 0.014) respectively. CONCLUSIONS: Moderate FMR and moderate-to-severe/severe FMR independently predict an unfavorable prognosis in patients with HFmrEF.


Subject(s)
Heart Failure , Mitral Valve Insufficiency , Patient Admission , Patient Readmission , Registries , Severity of Illness Index , Stroke Volume , Ventricular Function, Left , Humans , Mitral Valve Insufficiency/physiopathology , Mitral Valve Insufficiency/mortality , Mitral Valve Insufficiency/diagnostic imaging , Mitral Valve Insufficiency/epidemiology , Heart Failure/physiopathology , Heart Failure/mortality , Heart Failure/diagnosis , Heart Failure/therapy , Male , Female , Middle Aged , Prospective Studies , Aged , Time Factors , Risk Factors , Acute Disease , Prognosis , China/epidemiology , Risk Assessment
4.
Article in English | MEDLINE | ID: mdl-38996753

ABSTRACT

Metalloproteins binding with trace elements play a crucial role in biological processes and on the contrary, those binding with exogenous heavy metals have adverse effects. However, the methods for rapid, high sensitivity and simultaneous analysis of these metalloproteins are still lacking. In this study, a fast method for simultaneously determination of both essential and toxic metal-containing proteins was developed by coupling size exclusion chromatography (SEC) with inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). After optimization of the separation and detection conditions, seven metalloproteins with different molecular weight (from 16.0 to 443.0 kDa) were successfully separated within 10 min and the proteins containing iron (Fe), copper (Cu), zinc (Zn), iodine (I) and lead (Pb) elements could be simultaneously detected with the use of oxygen as the collision gas in ICP-MS/MS. Accordingly, the linear relationship between log molecular weight and retention time was established to estimate the molecular weight of unknown proteins. Thus, the trace metal and toxic metal containing proteins could be detected in a single run with high sensitivity (detection limits in the range of 0.0020-2.5 µg/mL) and good repeatability (relative standard deviations lower than 4.5 %). This method was then successfully used to analyze metal (e.g., Pb, Zn, Cu and Fe) binding proteins in the blood of Pb-intoxicated patients, and the results showed a negative correlation between the contents of zinc and lead binding proteins, which was identified to contain hemoglobin subunit. In summary, this work provided a rapid and sensitive tool for screening metal containing proteins in large number of biological samples.

5.
Front Med (Lausanne) ; 11: 1372091, 2024.
Article in English | MEDLINE | ID: mdl-38962734

ABSTRACT

Introduction: Microaneurysms serve as early signs of diabetic retinopathy, and their accurate detection is critical for effective treatment. Due to their low contrast and similarity to retinal vessels, distinguishing microaneurysms from background noise and retinal vessels in fluorescein fundus angiography (FFA) images poses a significant challenge. Methods: We present a model for automatic detection of microaneurysms. FFA images were pre-processed using Top-hat transformation, Gray-stretching, and Gaussian filter techniques to eliminate noise. The candidate microaneurysms were coarsely segmented using an improved matched filter algorithm. Real microaneurysms were segmented by a morphological strategy. To evaluate the segmentation performance, our proposed model was compared against other models, including Otsu's method, Region Growing, Global Threshold, Matched Filter, Fuzzy c-means, and K-means, using both self-constructed and publicly available datasets. Performance metrics such as accuracy, sensitivity, specificity, positive predictive value, and intersection-over-union were calculated. Results: The proposed model outperforms other models in terms of accuracy, sensitivity, specificity, positive predictive value, and intersection-over-union. The segmentation results obtained with our model closely align with benchmark standard. Our model demonstrates significant advantages for microaneurysm segmentation in FFA images and holds promise for clinical application in the diagnosis of diabetic retinopathy. Conclusion: The proposed model offers a robust and accurate approach to microaneurysm detection, outperforming existing methods and demonstrating potential for clinical application in the effective treatment of diabetic retinopathy.

6.
Org Lett ; 26(28): 5905-5910, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-38980194

ABSTRACT

Herein, we present a straightforward approach to access hydroindoline-5-one-based 6/5/3-fused polycyclic ring structures through multistep cascade reactions involving α-aryl vinylsulfoniums and para-quinamines. The reactions proceed smoothly under mild conditions to deliver the desired products in generally good isolated yields. This protocol is also applicable to the cascade cycloaddition reactions of α-aryl vinylsulfoniums and para-quinols, effectively generating complex tricyclic scaffolds. In addition, the scale-up synthesis and further derivatizations demonstrate the potential synthetic application of the protocol.

7.
Molecules ; 29(11)2024 May 24.
Article in English | MEDLINE | ID: mdl-38893357

ABSTRACT

Quinone imines are important derivatives of quinones with a wide range of applications in organic synthesis and the pharmaceutical industry. The attack of nucleophilic reagents on quinone imines tends to lead to aromatization of the quinone skeleton, resulting in both the high reactivity and the unique reactivity of quinone imines. The extreme value of quinone imines in the construction of nitrogen- or oxygen-containing heterocycles has attracted widespread attention, and remarkable advances have been reported recently. This review provides an overview of the application of quinone imines in the synthesis of cyclic compounds via the domino annulation reaction.

9.
Chempluschem ; : e202400287, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940320

ABSTRACT

Mechanochemistry constitutes a burgeoning field that investigates the chemical and physicochemical alterations of substances under mechanical force. It enables the synthesis of materials which was challenging to access via conventional thermal, optical, and electrical activation methods. In addition, it diminishes reliance on organic solvents and provides a novel route for green chemistry. Today, as a distinct branch alongside electrochemistry, photochemistry, and thermochemistry, mechanochemistry has emerged as an intersected research field with chemistry and material science. In recent years, the combination of mechanochemistry with controlled radical polymerization has witnessed rapid advancement, providing new sights to polymer science. The mechanochemically controlled radical polymerization (mechano-CRP) not only facilitate the synthesis of polymers with high molecular weight but also enable precise control over polymer chain length and structure. To diminish the side reactions by the strong mechanical force, transitioning from harsh to mild conditions in mechanochemical routes has been recognized as one of the primary advancements. From this perspective, we introduce the progress of mechanochemistry in controlled radical polymerization in recent years, aim to clarify the development trend of this research direction and stimulate senior researchers or newcomers to contemplate the future direction of this field.

10.
Biology (Basel) ; 13(6)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38927339

ABSTRACT

Seaweed farming has made outstanding contributions to food supply and the restoration of the ecological environment despite the limitations in production and ecological effects due to the current intensive farming of single algae species. These limitations can be overcome by selecting suitable algal species based on their physiological characteristics and by constructing a large-scale seaweed rotation model. This study carried out a trial culture in aquaculture sea areas, and performed in situ monitoring of the environmental conditions and physiological characteristics of Saccharina japonica, Hizikia fusiformis, and Gracilariopsis lemaneiformis. Additionally, a comparative analysis of the three macroalgae at different times was conducted to determine their response characteristics to environmental factors. The results showed that: (1) The three macroalgae had varying light tolerance. The effective quantum yield of Hizikia fusiformis and Gracilariopsis lemaneiformis remained unchanged during the changes in light environment, while that of Saccharina japonica first decreased and then recovered. (2) The relative electron transport rates of the three macroalgae were significantly different under different temperature conditions. Hizikia fusiformis and Saccharina japonica exhibited the highest relative electron transport rates (70.45 and 106.75, respectively) in May (20.3 °C). Notably, Gracilariopsis lemaneiformis demonstrated good growth and exhibited the highest relative electron transport rate (93.07) in September (27.5 °C). These findings collectively support the feasibility of establishing a macroalgae rotation model. Based on the combined environmental conditions of the seas in Shandong, Zhejiang, and Fujian, a macroalgae rotation model was proposed. The application of this model in the construction of artificial seaweed farms in marine ranches can provide a stable output of large-scale seaweed production and ecological benefits.

11.
Biomimetics (Basel) ; 9(6)2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38921223

ABSTRACT

The beetle, of the order Coleoptera, possesses outstanding flight capabilities. After completing flight, they can fold their hindwings under the elytra and swiftly unfold them again when they take off. This sophisticated hindwing structure is a result of biological evolution, showcasing the strong environmental adaptability of this species. The beetle's hindwings can provide biomimetic inspiration for the design of flapping-wing micro air vehicles (FWMAVs). In this study, the Asian ladybird (Harmonia axyridis Pallas) was chosen as the bionic research object. Various kinematic parameters of its flapping flight were analyzed, including the flight characteristics of the hindwings, wing tip motion trajectories, and aerodynamic characteristics. Based on these results, a flapping kinematic model of the Asian ladybird was established. Then, three bionic deployable wing models were designed and their structural mechanical properties were analyzed. The results show that the structure of wing vein bars determined the mechanical properties of the bionic wing. This study can provide a theoretical basis and technical reference for further bionic wing design.

12.
Antioxidants (Basel) ; 13(6)2024 May 21.
Article in English | MEDLINE | ID: mdl-38929067

ABSTRACT

BACKGROUND: Our previous studies have shown that scorpion venom heat-resistant synthesized peptide (SVHRSP) induces a significant extension in lifespan and improvements in age-related physiological functions in worms. However, the mechanism underlying the potential anti-aging effects of SVHRSP in mammals remains elusive. METHODS: Following SVHRSP treatment in senescence-accelerated mouse resistant 1 (SAMR1) or senescence-accelerated mouse prone 8 (SAMP8) mice, behavioral tests were conducted and brain tissues were collected for morphological analysis, electrophysiology experiments, flow cytometry, and protein or gene expression. The human neuroblastoma cell line (SH-SY5Y) was subjected to H2O2 treatment in cell experiments, aiming to establish a cytotoxic model that mimics cellular senescence. This model was utilized to investigate the regulatory mechanisms underlying oxidative stress and neuroinflammation associated with age-related cognitive impairment mediated by SVHRSP. RESULTS: SVHRSP significantly ameliorated age-related cognitive decline, enhanced long-term potentiation, restored synaptic loss, and upregulated the expression of synaptic proteins, therefore indicating an improvement in synaptic plasticity. Moreover, SVHRSP demonstrated a decline in senescent markers, including SA-ß-gal enzyme activity, P16, P21, SIRT1, and cell cycle arrest. The underlying mechanisms involve an upregulation of antioxidant enzyme activity and a reduction in oxidative stress-induced damage. Furthermore, SVHRSP regulated the nucleoplasmic distribution of NRF2 through the SIRT1-P53 pathway. Further investigation indicated a reduction in the expression of proinflammatory factors in the brain after SVHRSP treatment. SVHRSP attenuated neuroinflammation by regulating the NF-κB nucleoplasmic distribution and inhibiting microglial and astrocytic activation through the SIRT1-NF-κB pathway. Additionally, SVHRSP significantly augmented Nissl body count while suppressing neuronal loss. CONCLUSION: SVHRSP could remarkably improve cognitive deficiency by inhibiting oxidative stress and neuroinflammation, thus representing an effective strategy to improve brain health.

13.
J Org Chem ; 89(12): 8363-8375, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38848119

ABSTRACT

Palladium-catalyzed decarboxylation of 5-methylene-1,3-oxazinan-2-ones and 5-methylene-1,3-dioxan-2-ones to generate aza-π-allylpalladium and oxa-π-allylpalladium 1,4-dipoles for [4 + 2] cycloaddition reaction with 1,3,5-triazinanes was developed, affording a wide range of hexahydropyrimidine and 1,3-oxazinane derivatives in good to excellent yields (up to 99%). The acyclic sulfonamido-substituted allylic carbonates as aza-π-allylpalladium 1,4-dipole precursors also apply to the developed synthesized strategy, achieving the synthesis of hexahydropyrimidines. Moreover, the in situ-generated aza-π-allylpalladium 1,4-dipoles undergoing dimeric [4 + 4] cycloaddition were also demonstrated by the construction of 1,5-diazocane derivatives.

14.
Patient Prefer Adherence ; 18: 1217-1230, 2024.
Article in English | MEDLINE | ID: mdl-38895637

ABSTRACT

Purpose: Understanding the quality of life and the factors that influence it for patients with short bowel syndrome (SBS) and their caregivers is of utmost importance in order to enhance their well-being. Therefore, This study aimed to provide a comprehensive understanding of the impact of SBS on patients and their caregivers, as well as its associated factors, by synthesizing the available evidence. Methods: A systematic review of the literature was done using PubMed, Embase databases, CNKI, and ISPOR conference papers. Included articles were manually searched to identify any other relevant studies. Quality was assessed using appropriate Joanna Briggs Institute critical appraisal tools. Results: This review included 16 studies, comprising 15 observational studies and 1 randomized controlled trial. The findings revealed that the QoL of patients with SBS was lower than that of the general population regarding physical functioning and psychological domain. Meanwhile, caregivers experienced challenges in maintaining their QoL. The QoL of SBS patients was found to be influenced by various factors such as treatment, age, sex, stoma, and small intestine length. Among them, the treatment is the most noteworthy factor that can be effectively improved through external interventions. Conclusion: While numerous studies have provided insights into the compromised QoL experienced by individuals with SBS and their caregivers, there remains a scarcity of large-sample quantitative investigations examining the determinants of QoL. The existing body of literature on caregivers is also notably deficient.

15.
Pak J Pharm Sci ; 37(2(Special)): 435-442, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38822547

ABSTRACT

Depression is a common non-motor symptom of Parkinson's disease. Previous studies demonstrated that hydroxysafflor yellow A had properties of improving motor symptoms of Parkinson's disease. The effect of hydroxysafflor yellow A on depression in Parkinson's disease mice is investigated in this study. To induce Parkinson's disease model, male Swiss mice were exposed to rotenone (30 mg/kg) for 6 weeks. The chronic unpredictable mild stress was employed to induce depression from week 3 to week 6. Sucrose preference, tail suspension, and forced swimming tests were conducted. Golgi and Nissl staining of hippocampus were carried out. The levels of dopamine, 5-hydroxytryptamine and the expression of postsynaptic density protein 95, brain-derived neurotrophic factor in hippocampus were assayed. It showed that HSYA improved the depression-like behaviors of Parkinson's disease mice. Hydroxysafflor yellow A attenuated the injury of nerve and elevated contents of dopamine, 5-hydroxytryptamine in hippocampus. Treatment with hydroxysafflor yellow A also augmented the expression of postsynaptic density protein 95 and brain-derived neurotrophic factor. These findings suggest that hydroxysafflor yellow A ameliorates depression-like behavior in Parkinson's disease mice through regulating the contents of postsynaptic density protein 95 and brain-derived neurotrophic factor, therefore protecting neurons and neuronal dendrites of the hippocampus.


Subject(s)
Behavior, Animal , Brain-Derived Neurotrophic Factor , Chalcone , Depression , Hippocampus , Quinones , Serotonin , Animals , Quinones/pharmacology , Quinones/therapeutic use , Chalcone/analogs & derivatives , Chalcone/pharmacology , Chalcone/therapeutic use , Male , Mice , Brain-Derived Neurotrophic Factor/metabolism , Depression/drug therapy , Depression/metabolism , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Behavior, Animal/drug effects , Serotonin/metabolism , Dopamine/metabolism , Rotenone/pharmacology , Disease Models, Animal , Disks Large Homolog 4 Protein/metabolism , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , Parkinson Disease/psychology
16.
Nanoscale ; 16(23): 11005-11018, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38774955

ABSTRACT

Lithium-sulfur batteries (Li-S batteries) are being widely studied as promising energy-storage solutions for the next generation owing to their excellent properties including high energy density, eco-friendliness, and low cost. Nevertheless, drawbacks, especially the severe "shuttle effect" and slow transformation of polysulfides, hinder the road to commercialization of Li-S batteries. The functional utilization of metal compounds in Li-S batteries has been verified, such as enhancing the conductivity, adsorption of lithium polysulfides (LPSs) and improving the kinetics of electrode processes. Benefiting from the outstanding catalytic capability and relatively good conductivity, metal phosphides have gradually received intense attention over the past few years. Consequently, significant progress has been achieved in the optimization of phosphides for Li-S batteries in recent years. This review introduces the application of metal phosphides in Li-S batteries from the aspects of their own characteristics, material structure design, and material interface control. The aim of this review is to enhance the understanding of the operational mechanism of metal phosphides and provide guidance for the development of Li-S batteries.

17.
Environ Sci Pollut Res Int ; 31(25): 37175-37195, 2024 May.
Article in English | MEDLINE | ID: mdl-38764086

ABSTRACT

It is important to explore the characteristics and rules of atmospheric aerosol in the East Asian Sea for monitoring and evaluating atmospheric environmental quality. Based on Aerosol Robot Network (AERONET), Visible Infrared Imaging Radiometer (VIIRS), and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data, the temporal and spatial variation characteristics and differences of aerosol parameters and types in the East Asian Sea were studied by using figure classification method (FIGCM), aerosol optical depth (AOD)440-Angstrom exponent (AE)440-870 method (AA1M), and AOD550-AE490-670 method (AA2M). The results show that the seasonal variation trend of aerosol characteristics and types is obvious in East Asia Sea. AOD, volume concentration (Cv), and aerosol effective radius (reff) in the Bohai-Yellow Sea and the Sea of Japan in autumn are lower than those in other seasons, and the occurrence frequency of ocean-type aerosols is high. Different from the Bohai-Yellow Sea and Sea of Japan, human activities in winter, summer, and autumn seriously affect the air quality in the East China Sea and South China Sea. Especially at the Taipei CWB site, from aerosol parameters and high biomass burning/urban industrial (BB/UI) aerosol, human activity is an important factor for high pollution at the Taipei CWB site. Aerosol types of AA1M, FIGCM, AA2M, and CALIPSO were compared at Anmyon and Yonsei University sites in the Bohai-Yellow Sea in March 2020. The results show that aerosol types based on threshold classification methods generally have higher mixed aerosol results, and the marine (MA) results of AA1M, FIGCM, and AA2M are close to the clean marine aerosol results of CALIPSO. Comparing the results of AA 2 M and CALIPSO on a spatial scale, it is found that the clean marine aerosol proportion identified by CALIPSO (0.38, 0.48, 0.82) is consistent with the MA proportion identified by AA 2 M (0.43, 0.46, 0.97) in the East China Sea, South China Sea, and Western Pacific Ocean.


Subject(s)
Aerosols , Environmental Monitoring , Oceans and Seas , Remote Sensing Technology , Aerosols/analysis , Environmental Monitoring/methods , Air Pollutants/analysis , Asia, Eastern , Atmosphere/chemistry , Seasons , China
18.
New Phytol ; 243(2): 567-579, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38812270

ABSTRACT

Aerosols could significantly influence ecosystem carbon and water fluxes, potentially altering their interconnected dynamics, typically characterized by water-use efficiency (WUE). However, our understanding of the underlying ecophysiological mechanisms remains limited due to insufficient field observations. We conducted 4-yr measurements of leaf photosynthesis and transpiration, as well as 3-yr measurements of stem growth (SG) and sap flow of poplar trees exposed to natural aerosol fluctuation, to elucidate aerosol's impact on plant WUE. We found that aerosol improved sun leaf WUE mainly because a sharp decline in photosynthetically active radiation (PAR) inhibited its transpiration, while photosynthesis was less affected, as the negative effect induced by declined PAR was offset by the positive effect induced by low leaf vapor pressure deficit (VPDleaf). Conversely, diffuse radiation fertilization (DRF) effect stimulated shade leaf photosynthesis with minimal impact on transpiration, leading to an improved WUE. The responses were further verified by a strong DRF on SG and a decrease in sap flow due to the suppresses in total radiation and VPD. Our field observations indicate that, contrary to the commonly assumed coupling response, carbon uptake and water use exhibited dissimilar reactions to aerosol pollution, ultimately enhancing WUE at the leaf and canopy level.


Subject(s)
Aerosols , Carbon , Photosynthesis , Plant Leaves , Plant Transpiration , Populus , Water , Water/metabolism , Photosynthesis/radiation effects , Photosynthesis/drug effects , Carbon/metabolism , Plant Leaves/physiology , Plant Leaves/radiation effects , Plant Leaves/drug effects , Plant Transpiration/physiology , Plant Transpiration/radiation effects , Populus/physiology , Populus/radiation effects , Populus/drug effects , Plant Stems/radiation effects , Plant Stems/drug effects , Plant Stems/physiology
19.
J Environ Manage ; 360: 121155, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38761624

ABSTRACT

The establishment of large hydropower stations in the main stream poses a threat to fish habitats. Selecting suitable tributaries as alternative habitats is a practical measure for ecological environment protection during large hydropower station's construction. The small dams constructed on certain tributaries need to be removed in order to restore river connectivity. The removal of dams will activate hydro-sedimentary dynamics and change the original habitat in terms of topography and hydrodynamics. To explore the evolution of fish habitats following the removal of small dams, a dam-removed reach of a habitat-alternative tributary was selected as the research object, and the model of water-sediment transport and riverbed evolution in strongly disturbed dam-removed reaches and the model of fish habitat suitability evaluation were established. The key parameters calibration and model verification were completed by field monitoring results. The simulation results showed dramatic evolution in the reservoir riverbed in the initial stage after dam removal and during the high discharge period. One year after dam removal, there was a noticeable 4.0 m incision in front of the dam, along with a decrease in channel slope at the dam site from about 4.8% to approximately 1.5%. Downstream of the dam, alterations to the riverbed were mainly concentrated near the dam, and sedimentary bodies with a height of around 2.0 m have formed on the left bank following the high discharge period. The fish habitat in most areas of the dam-removed reach was suitable, except for the downstream high-velocity area. To compare the evolution process of fish habitat under two dam removal periods in wet and dry seasons, two dam removal schemes were implemented in March and June. The results showed that the riverbed evolved more gradually in the March scheme, creating a larger and continuous suitable habitat for fish. Therefore, the March scheme was recommended. By revealing the evolutionary pattern of fish habitat after dam removal, this research provides a reliable model for assessing and restoring habitats in dam-removed reaches, and enjoys significant implications for protecting river ecology in hydropower development reaches.


Subject(s)
Ecosystem , Rivers , Animals , Fishes , Power Plants , Conservation of Natural Resources
20.
Anal Chim Acta ; 1307: 342622, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38719403

ABSTRACT

BACKGROUND: Trace levels of organic and inorganic lead and mercury species in the environment, including divalent lead (Pb2+), trimethyllead (TML), divalent mercury (Hg2+), monomethylmercury (MeHg), and ethylmercury (EtHg), are highly toxic to humans and ecology. It is of great importance for speciation of lead and mercury to evaluate the toxicity of lead and mercury and their biogeochemistry in the environment. However, simultaneous multi-elemental enrichment and speciation at trace level remains a challenge. There are few reports of simultaneous magnetic solid-phase extraction (MSPE) of organic and inorganic lead and mercury species at trace level in the real water. RESULTS: In this work, a novel core-shell magnetic hydrazine-linked covalent organic frameworks (Fe3O4@COF-TCH) was prepared for the first time by grafting hydrazine-linked COFs on the Fe3O4 nanoparticles. Fe3O4@COF-TCH with abundant thione and imino groups has strong adsorption for lead and mercury species. Based on it, a simple and practical magnetic solid-phase extraction high-performance liquid chromatography-inductively coupled plasma mass spectrometry (MSPE-HPLC-ICP-MS) method was developed for extraction and determination of trace lead and mercury species, including Hg2+, MeHg, EtHg, Pb2+ and TML. The limits of detection (3δ) of the developed method were 0.08, 0.81, 0.90, 0.56 and 0.88 ng L-1 with the enrichment factors (EFs) of 384, 376, 379, 389 and 360-fold for Pb2+, TML, Hg2+, MeHg and EtHg, respectively. The high accuracy and reproducibility have been proved by the spiked recoveries (94.4-103 %) in real samples. SIGNIFICANCE: The proposed method with simple operation and high sensitivity has been successfully applied to simultaneous speciation of lead and mercury at trace levels in the water samples with complicated matrices, including underground water, surface water, sea water. Meanwhile, it has the advantages of cost-saving, labor-saving and time-saving and is suitable for the investigation and risk assessment in water. The development of MSPE-HPLC-ICP-MS method provides ideas and guidance for the simultaneous multi-elemental enrichment and speciation.

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