Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 12 de 12
Filter
Add more filters










Publication year range
1.
Sci Total Environ ; 947: 174564, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38972401

ABSTRACT

The bacterial community in sediment serves as an important indicator for assessing the environmental health of river ecosystems. However, the response of bacterial community structure and function in river basin sediment to different land use/cover changes has not been widely studied. To characterize changes in the structure, composition, and function of bacterial communities under different types of land use/cover, we studied the bacterial communities and physicochemical properties of the surface sediments of rivers. Surface sediment in cropland and built-up areas was moderately polluted with cadmium and had high nitrogen and phosphorus levels, which disrupted the stability of bacterial communities. Significant differences in the α-diversity of bacterial communities were observed among different types of land use/cover. Bacterial α-diversity and energy sources were greater in woodlands than in cropland and built-up areas. The functional patterns of bacterial communities were shown that phosphorus levels and abundances of pathogenic bacteria and parasites were higher in cropland than in the other land use/cover types; Urban activities have resulted in the loss of the denitrification function and the accumulation of nitrogen in built-up areas, and bacteria in forested and agricultural areas play an important role in nitrogen degradation. Differences in heavy metal and nutrient inputs driven by land use/cover result in variation in the composition, structure, and function of bacterial communities.

2.
ACS Nano ; 18(19): 12134-12145, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38687780

ABSTRACT

We explore the FeRh magnetic phase transition (MPT) and magnetic phase domain (MPD) with the introduction of surface acoustic waves (SAWs). The effects of the SAW pulses with different pulse widths and powers on resistance-temperature loops are investigated, revealing that the SAW can reduce the thermal hysteresis. Meanwhile, the SAW-induced comb-like antiferromagnetic (AFM) phase domains are observed. By changing the pulse width and SAW frequency, we further realize a writing-erasing process of the different comb-like AFM phase domains in the mixed-phase regime of the cooling transition branch. Resistance measurements also display the repeated SAW writing-erasing and the nonvolatile characteristic clearly. MPT paths are measured to demonstrate that short SAW pulses induce isothermal MPT and write magnetic phase patterns via the dynamic strain, whereas long SAW pulses erase patterns via the acoustothermal effect. The Preisach model is introduced to model the FeRh MPT under the SAW pulses, and the calculated results correspond well with our experiments, which reveals the SAW-induced energy modulation promotes FeRh MPT. COMSOL simulations of the SAW strain field also support our results. Our study not only can be used to reduce the thermal hysteresis but also extends the application of the SAW as a tool to write and erase AFM patterns for spintronics and magnonics.

4.
J Environ Manage ; 351: 119832, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38128215

ABSTRACT

Phytoplankton is sensitive to changes in river ecosystems. Increasing dams disrupt the continuity of river ecosystems. However, the spatial impacts of dams on phytoplankton have not been well documented. In this study, using multiple statistical analyses, the relationships between environmental drivers and phytoplankton community structures in natural background reaches, reservoirs, and corresponding post-dam reaches were explored in the Jiulong River with multiple cascaded dams, which encountered eutrophication and algal blooms in the past 15 years. Results illustrated that damming exacerbated longitudinal discontinuities of phytoplankton communities. The relative abundance of phytoplankton varied in three types of river sections. The average phytoplankton abundance in the reservoirs (1.62 × 105 cell·L-1) was higher than those in the natural background reaches (5.15 × 104 cell·L-1) and the corresponding downstream reaches (4.55 × 104 cell·L-1). The total ß diversity ranged from 0.38 to 0.89 with an average of 0.64 and dominated by species replacement and least by species richness. The water environmental factors and hydraulic parameters rather than nutrients were more attributable to phytoplankton community variability in three river sections. These findings facilitate the management of rivers with multiple cascade dams by releasing environmental flows, jointly operating cascade hydropower stations, and developing nutrient reduction schemes to mitigate the negative impacts of damming in the river.


Subject(s)
Ecosystem , Phytoplankton , Seasons , Rivers/chemistry , China , Environmental Monitoring
6.
Sci Rep ; 12(1): 6355, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35428821

ABSTRACT

The traditional titanomagnetite sintering process consumes high fuel and produces weak-strength sinter. In this study, double-layer sintering was used to solve above problems. The theoretical analysis and sintering pot test results showed that sintering of feed bed constituted by two different-basicity layers could improve mineralization and permeability. By using the double layer structure of sintering bed and controlling the basicities of lower and upper layer (2.5 and 1.5, respectively), the yield, productivity, and reduction disintegration index (RDI+3.15) were 67.32%, 1.65 t m2 h-1, 49.68% respectively, which were improved 33.12%, 1.74%, and 9.27%, respectively than those obtained by the traditional sintering process. Meanwhile, 1.69 kg t-1 of solid fuel consumption and nearly 10% of electricity and gas consumption for sintering were saved. It was demonstrated that using different basicities for upper and lower layer of sintering bed would promote formation of silica-ferrite of calcium and aluminum (SFCA) with simultaneous reduction of perovskite, improving the sinter quality.

7.
Chin J Nat Med ; 19(11): 874-880, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34844726

ABSTRACT

Nine new compounds, including five natural rarely-occurring 2, 3-dihydro-1H-indene derivatives named diaporindenes E-I (1-5), and four new benzophenone analogues named tenellones J-M (6-9) were isolated from the deep-sea sediment-derived fungus Phomopsis lithocarpus FS508. All the structures for these new compounds were fully characterized on the basis of spectroscopic data, NMR spectra, and ECD calculation and single-crystal X-ray diffraction analysis. The potential anti-tumor activities of compounds 1-9 against four tumor cell lines SF-268, MCF-7, HepG-2, and A549 were evaluated using the SRB method. Compound 7 exhibited cytotoxic activity against the SF-268 cell line with an IC50 value of 11.36 µmol·L-1.


Subject(s)
Antineoplastic Agents , Phomopsis , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Crystallography, X-Ray , Fungi , Molecular Structure
8.
Front Oncol ; 11: 700168, 2021.
Article in English | MEDLINE | ID: mdl-34195097

ABSTRACT

Gastric cancer (GC) is one of the most common fatal cancers worldwide. The communication between GC and other cells in the GC microenvironment directly affects GC progression. Recently, exosomes have been revealed as new players in intercellular communication. They play an important role in human health and diseases, including cancer, owing to their ability to carry various bioactive molecules, including non-coding RNAs (ncRNAs). NcRNAs, including micro RNAs, long non-coding RNAs, and circular RNAs, play a significant role in various pathophysiological processes, especially cancer. Increasing evidence has shown that exosomal ncRNAs are involved in the regulation of tumor proliferation, invasion, metastasis, angiogenesis, immune regulation, and treatment resistance in GC. In addition, exosomal ncRNAs have promising potential as diagnostic and prognostic markers for GC. Considering the biocompatibility of exosomes, they can also be used as biological carriers for targeted therapy. This review summarizes the current research progress on exosomal ncRNAs in gastric cancer, focusing on their biological role in GC and their potential as new biomarkers for GC and therapeutics. Our review provides insight into the mechanisms involved in GC progression, which may provide a new point cut for the discovery of new diagnostic markers and therapeutic strategies.

9.
Medicine (Baltimore) ; 100(6): e23589, 2021 Feb 12.
Article in English | MEDLINE | ID: mdl-33578510

ABSTRACT

RATIONALE: Postoperative intracranial hemorrhage is a serious and even fatal complication after non-traumatic craniotomy, in which epidural hematoma and intracerebral hematoma are relatively common. Postoperative subdural hematoma is rare, and its pathogenic mechanism remains unclear. PATIENT CONCERNS: In the present study, we report 2 cases with postoperative subdural hematoma after non-traumatic craniotomy. DIAGNOSES: The diagnosis of acute subdural hematoma (aSDH) was rendered according to the imaging features. INTERVENTIONS: Hematoma evacuation was performed immediately. OUTCOMES: Two months later, the first patient continued to have impaired consciousness and sensorimotor deficiency in the right extremities. And the second one remained unconscious and continued to have sensorimotor disturbance in the right extremities after 6 weeks of rehabilitation. LESSONS: Neurosurgeons should be aware of potential subdural hematoma after non-traumatic craniotomy, since this condition is usually latent and associated with poor prognosis. Early identification and surgical evacuation should be highlighted.


Subject(s)
Craniotomy/adverse effects , Hematoma, Subdural, Acute/etiology , Postoperative Complications/surgery , Adult , Awareness , Early Diagnosis , Hematoma, Subdural, Acute/diagnostic imaging , Hematoma, Subdural, Acute/surgery , Humans , Male , Middle Aged , Neurosurgeons , Postoperative Complications/pathology , Postoperative Period , Prognosis , Tomography, X-Ray Computed/methods
10.
Onco Targets Ther ; 13: 12965-12977, 2020.
Article in English | MEDLINE | ID: mdl-33376346

ABSTRACT

PURPOSE: Exosomes contain abundant circRNAs and are determined to be involved in the pathogenesis of lung adenocarcinoma (LUAD). Thus, our study aimed to explore new circRNAs in plasma exosomes that could be involved in such pathogenesis. PATIENTS AND METHODS: High-throughput sequencing was used in identifying the alterations in exosomal circRNA expression. Gene ontology functional analysis (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to determine the significant functions and pathways associated with differentially expressed circRNAs. TargetScan and miRanda were used to predict circRNA-targeted microRNAs and mRNAs. CircRNA expression profiles were then validated by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Wound healing and Transwell assays were performed to determine the roles of has_circ_0102537 in LUAD progression. RESULTS: We identified six significantly upregulated and 214 significantly downregulated circRNAs. GO and KEGG pathway analysis suggested that the differentially expressed circRNAs are involved in the occurrence and development of LUAD. A circRNA-miRNA-mRNA meshwork was established to predict the potential interactions among these RNAs. The circRNA expression profile was then subjected to qRT-PCR for validation. We identified hsa_circ_0102537 to be downregulated in both LUAD plasma exosomes and tissues. GO, KEGG pathway analysis, circRNA-miRNA-mRNA meshwork, and further experiments suggest that hsa_circ_0102537 could be involved in LUAD progression. CONCLUSION: Our study explored a large number of circRNAs that may be involved in the LUAD pathogenesis, thereby supporting the need for further research on both diagnosis biomarkers and the potential intervention therapeutic targets.

11.
Org Biomol Chem ; 18(37): 7326-7329, 2020 09 30.
Article in English | MEDLINE | ID: mdl-32940323

ABSTRACT

Lithocaldehydes A (1) and B (2), a pair of novel diastereoisomers possessing an unprecedented 6/6/5/5/6 highly-fused ring system forming an earring-like skeleton, were isolated from the deep sea-derived fungus Phomopsis lithocarpus FS508. The structures of 1 and 2 were fully characterized and established through extensive spectroscopic interpretations and ECD calculations. Moreover, compounds 1 and 2 were shown to be promising antibiotics, exhibiting potent antifungal activities that are comparable to those of the positive control nystatin.


Subject(s)
Phomopsis
12.
Fitoterapia ; 137: 104260, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31284016

ABSTRACT

One new benzophenone derivative, named tenllone I (1), two new eremophilane derivatives lithocarins B (2) and C (3), and a new monoterpentoid lithocarin D (4), together with two know compounds (5 and 6) were isolated from the endophytic fungus Diaporthe lithocarpus A740. All of the structures for these new compounds were fully characterized and established on the basis of extensive spectroscopic interpretation. In addition, all the isolated compounds were evaluated in vitro for their cytotoxic activity. Compounds 2, 3, and 5 showed weak inhibitory activities against tumor cell lines.


Subject(s)
Ascomycota/chemistry , Benzophenones/isolation & purification , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Benzophenones/pharmacology , Cell Line, Tumor , China , Endophytes/chemistry , Humans , Molecular Structure , Morinda/microbiology
SELECTION OF CITATIONS
SEARCH DETAIL
...