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1.
Phys Rev E ; 109(6-2): 065208, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39021005

RESUMEN

Here a mechanism for self-compression of laser pulses is presented, based on period density-modulated plasma. In this setup, two pump beams intersect at a small angle within the plasma. This interaction is facilitated by the ponderomotive ion mechanism, which causes a modulation in the density of plasma with long wavelengths and low amplitude. This modulation enhances the backward Raman scattering of the probe pulse. The trailing edge of the probe experiences greater energy loss, resulting in a steeper intensity gradient. This, in turn, induces an asymmetric self-phase modulation, which elevates the instantaneous frequency. It is notable that the laser in plasma exhibits opposite group velocity dispersion compared to traditional solid-state media. This unique property allows laser pulses to undergo dispersion compensation while broadening the spectrum, ultimately leading to self-compression. The 2D-PIC simulations demonstrate these phenomena, highlighting how period density-modulated plasma contributes to an asymmetric spectral distribution. The intricate interplay among self-phase modulation, group velocity, and backward Raman scattering results in the self-compressing of the laser pulse. Specifically, the pulses are compressed from their Fourier transform limit duration of 50 fs to a significantly reduced duration of 8 fs at plasma densities below 1/4 critical density, without the transverse self-focusing effects.

2.
Nat Commun ; 15(1): 6041, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39019903

RESUMEN

Electrification plays a crucial role in deep decarbonization. However, electrification and power infrastructure can cause mutual challenges. We use nationwide power outage and electric vehicle adoption data in China to provide empirical evidence on how power infrastructure failures can deter electrification. We find that when the number of power outages per district increases by 1 in a given month, the number of new electric vehicles adopted per month decreases by 0.99%. A doubling of power outages in one year on average across the nation can create a depressed adoption rate for up to a decade, implying a decline of more than $ 31.3 million per year in carbon reduction benefits from electric vehicle adoptions. This paper adds to the policy discussion of the costs of increased power outages due to extreme weather and natural disasters, and the urgency for policy to address this issue to facilitate wide adoption of electrification.

3.
Environ Sci Technol ; 58(26): 11342-11351, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38875720

RESUMEN

Municipal solid waste (MSW) management systems play a crucial role in greenhouse gas (GHG) emissions in China. Although the government has implemented many policies to improve the MSW management system, the impact of these improvements on city-level GHG emission reduction remains largely unexplored. This study conducted a comprehensive analysis of both direct and downstream GHG emissions from the MSW sector, encompassing sanitary landfill, dump, incineration, and biological treatment, across 352 Chinese cities from 2001 to 2021 by adopting inventory methods recommended by the Intergovernmental Panel on Climate Change (IPCC). The results reveal that (1) GHG emissions from the MSW sector in China peaked at 70.6 Tg of CO2 equiv in 2018, followed by a significant decline to 47.6 Tg of CO2 equiv in 2021, (2) cities with the highest GHG emission reduction benefits in the MSW sector were historical emission hotspots over the past 2 decades, and (3) with the potential achievement of zero-landfilling policy by 2030, an additional reduction of 203.7 Tg of CO2 equiv is projected, with the emission reduction focus toward cities in South China (21.9%), Northeast China (17.8%), and Southwest China (17.3%). This study highlights that, even without explicit emission reduction targets for the MSW sector, the improvements of this sector have significantly reduced GHG emissions in China.


Asunto(s)
Gases de Efecto Invernadero , Residuos Sólidos , China , Ciudades , Eliminación de Residuos , Dióxido de Carbono/análisis
4.
Nat Cell Biol ; 26(6): 878-891, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38783142

RESUMEN

When cells are stressed, DNA from energy-producing mitochondria can leak out and drive inflammatory immune responses if not cleared. Cells employ a quality control system called autophagy to specifically degrade damaged components. We discovered that mitochondrial transcription factor A (TFAM)-a protein that binds mitochondrial DNA (mtDNA)-helps to eliminate leaked mtDNA by interacting with the autophagy protein LC3 through an autolysosomal pathway (we term this nucleoid-phagy). TFAM contains a molecular zip code called the LC3 interacting region (LIR) motif that enables this binding. Although mutating TFAM's LIR motif did not affect its normal mitochondrial functions, more mtDNA accumulated in the cell cytoplasm, activating inflammatory signalling pathways. Thus, TFAM mediates autophagic removal of leaked mtDNA to restrict inflammation. Identifying this mechanism advances understanding of how cells exploit autophagy machinery to selectively target and degrade inflammatory mtDNA. These findings could inform research on diseases involving mitochondrial damage and inflammation.


Asunto(s)
Autofagia , ADN Mitocondrial , Proteínas de Unión al ADN , Inflamación , Mitocondrias , Proteínas Mitocondriales , Factores de Transcripción , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Inflamación/metabolismo , Inflamación/patología , Inflamación/genética , Animales , Humanos , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Mitocondrias/metabolismo , Mitocondrias/genética , Ratones , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Unión Proteica , Citoplasma/metabolismo , Lisosomas/metabolismo , Transducción de Señal , Células HEK293 , Ratones Endogámicos C57BL , Proteínas del Grupo de Alta Movilidad
5.
Acta Biomater ; 183: 356-370, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38768742

RESUMEN

Zirconia is one of the most commonly used materials for abutments of dental implants, especially in the anterior region. Soft tissue integration to the zirconia abutment surface remains a challenge. Peri-implant soft tissue integration serves as a physiological barrier, attenuating pathogen penetration and preventing peri­implant disease. The surface microstructure of zirconia has significant effects on the biological behaviors of human gingival fibroblasts (HGFs), but the effects under inflammatory conditions are still unclear. In this study, we established two micro-nano structures on zirconia surfaces using a femtosecond laser, including microgrooves with widths of 30 µm (G3) and 60 µm (G6) and depths of 5 µm, and nanoparticles inside the microgrooves. Polished surfaces were used as controls. HGFs were seeded onto the three groups of zirconia specimens and stimulated with lipopolysaccharide. The HGFs on micro-nano-structured zirconia surfaces exhibited lower inflammatory responses and higher cell adhesion, proliferation, and migration under inflammatory conditions compared with the polished surfaces. Additionally, the G3 group exhibited lower inflammatory responses and higher cell adhesion and migration than the G6 group. The micro-nano-structured zirconia surface exhibited decreased neutrophil infiltration and increased M2-type macrophage polarization in vivo. To explore the molecular mechanism, RNA sequencing and gene silencing were utilized, which revealed two critical target genes regulated by the G3 group. Overall, we proposed an innovative micro-nano-structured zirconia surface that reduced the in vitro and in vivo inflammatory responses and promoted HGF adhesion, migration, and proliferation under inflammatory conditions, in which TRAFD1 and NLRC5 were the underlying key genes. STATEMENT OF SIGNIFICANCE: Zirconia is one of the most commonly used materials for abutments, especially in the anterior region. The surface microstructure of zirconia has significant effects on the biological behaviors of human gingival fibroblasts (HGFs), but few studies have investigated these effects under inflammatory conditions, and the mechanism remains unclear. In this study, we developed an innovative micro-nano-structured zirconia surface using a femtosecond laser, which reduces the in vitro and in vivo pro-inflammatory responses and promotes HGFs adhesion, migration, and proliferation under inflammatory conditions compared with the polished zirconia surface. The potential underlying mechanism was also investigated. This work has provided some theoretical basis for the micro-nano-structured zirconia surface in potentially reducing the inflammation and enhancing peri­implant soft-tissue integration under inflammatory conditions.


Asunto(s)
Fibroblastos , Encía , Inflamación , Propiedades de Superficie , Circonio , Circonio/farmacología , Circonio/química , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Encía/citología , Inflamación/patología , Proliferación Celular/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Animales , Movimiento Celular/efectos de los fármacos , Nanoestructuras/química , Ratones , Masculino
6.
Anal Methods ; 16(19): 3142-3153, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38713147

RESUMEN

We develop and validate a method for the rapid determination and identification of 20 ß-lactamase antibiotics traces in goat's milk by combining the solid phase extraction technology with ultra-high performance liquid chromatography-tandem mass spectrometry. Goat milk samples were extracted with acetonitrile twice. The supernatant was then extracted and cleaned by solid-phase extraction using divinylbenzene and N-vinylpyrrolidone copolymer. The method was validated, with limits of quantification (LOQs) of 0.3 µg kg-1, specificities of 1/3 LOQ, linearities (R2) > 0.99, recoveries of 80-110%, repeatabilities <10.0%, and intermediate precisions <10.0%. The developed method was suitable for the routine analysis of ß-lactamase antibiotics residues in goat's milk and was used to test 76 goat milk samples produced in China.


Asunto(s)
Antibacterianos , Cabras , Leche , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , beta-Lactamasas , Animales , Extracción en Fase Sólida/métodos , Leche/química , Espectrometría de Masas en Tándem/métodos , Antibacterianos/análisis , Cromatografía Líquida de Alta Presión/métodos , Límite de Detección , Reproducibilidad de los Resultados , Residuos de Medicamentos/análisis , Contaminación de Alimentos/análisis , Cromatografía Líquida con Espectrometría de Masas
7.
Arch Gynecol Obstet ; 309(6): 2863-2880, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38575798

RESUMEN

PURPOSES: To investigate the effect and safety of ovarian tissue cryopreservation (OTC) for fertility preservation in female patients with hematological diseases. METHODS: We designed a retrospective study. The clinical data of patients with hematological diseases undergoing OTC admitted to Peking University People's Hospital from April 2017 to January 2023 were analyzed and summarized. RESULTS: A total of 24 patients were included in the study, including 19 patients with malignant hematological diseases and 5 patients with non-malignant hematological diseases. The former included 14 patients with acute leukemia, 1 patient with chronic leukemia, and 4 patients with myelodysplastic syndrome, while the latter 5 patients were aplastic anemia (AA). 16 patients had received chemotherapy before OTC. The average age of 24 patients was 22.80 ± 6.81 years. The average anti-Mullerian hormone (AMH) was 1.97 ± 2.12 ng/mL, and the average follicle-stimulating hormone (FSH) was 7.01 ± 4.24 IU/L in examination before OTC. FSH was greater than 10.0 IU/L in 4 cases. The pre-OTC laboratory tests showed that the average white blood cell (WBC) count was (3.33 ± 1.35) × 109/L, the average hemoglobin was 91.42 ± 22.84 g/L, and the average platelet was (147.38 ± 114.46) × 109/L. After injection of recombinant human granulocyte colony-stimulating factor (rhG-CSF), blood transfusion, and iron supplementation in pre-OTC treatment, the average WBC count was (4.91 ± 3.07) × 109/L, the average hemoglobin was 98.67 ± 15.43 g/L, and the average platelet was (156.38 ± 103.22) × 109/L. Of the 24 patients, 22 underwent laparoscopic bilateral partial oophorectomy and oophoroplasty, and 2 underwent laparoscopic unilateral oophorectomy. The average duration of OTC was 59.54 ± 17.58 min, and the average blood loss was 32.1 ± 41.6 mL. The maximum blood loss was 200 mL. There was no significant difference in WBC count and hemoglobin concentration after OTC compared to pre-OTC period. Only the platelet count after OTC surgery was significantly different from that before surgery ([134.54 ± 80.84 vs. 156.38 ± 103.22] × 109/L, p < 0.05). None of the 24 patients had serious complications after OTC. 2 patients had mild infection symptoms, but both recovered well. 23 patients underwent hematopoietic stem cell transplantation (HSCT) after OTC. The median and interquartile range from OTC to the pretreatment of HSCT was 33 (57) days, and the median and interquartile range from OTC to HSCT was 41 (57) days. Seven of them began pretreatment of HSCT within 20 days and began HSCT within 30 days after OTC. All patients were followed up. Of the 23 patients who underwent HSCT after surgery, 22 presented with amenorrhea and 1 with scanty menstrual episodes. Seven patients underwent hormone replacement therapy (HRT) after HSCT. A patient with AA underwent ovarian tissue transplantation (OTT) 3 years after HSCT and resumed regular menstruation 6 months after OTT. CONCLUSIONS: Ovarian tissue cryopreservation has a promising future in fertility protection in patients with hematological diseases. However, patients with hematological malignancies often have received gonadotoxic therapy before OTC, which may be accompanied by myelosuppression while patients with non-malignant hematological diseases often present with severe hemocytopenia. So perioperative complete blood count of patients should be paid attention to. There was no significant difference in the WBC count and hemoglobin concentration in patients with hematological diseases before and after OTC surgery, and the platelet count decreased slightly within the normal range. Infection is the most common post-OTC complication, and HSCT pretreatment can be accepted as early as the 10th day after OTC. OTC has no adverse effects on patients with hematological diseases and does not delay HSCT treatment. For young patients with hematological diseases, OTC is an effective method of fertility preservation.


Asunto(s)
Criopreservación , Preservación de la Fertilidad , Ovario , Humanos , Femenino , Preservación de la Fertilidad/métodos , Estudios Retrospectivos , Adulto , Adulto Joven , Adolescente , Enfermedades Hematológicas/terapia , Hormona Antimülleriana/sangre , Hormona Folículo Estimulante/sangre , Síndromes Mielodisplásicos/terapia
8.
Curr Med Imaging ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38462829

RESUMEN

BACKGROUND: Fat-suppressed (FS) T2-weighed turbo spin-echo (TSE) sequence was used to detect the signal of the thymus and the characteristics of the thymus location, measure the two-dimensional diameter at specific levels, and analyze the association with gestational weeks. METHODS: This study involved 51 fetal specimens. Post-mortem MRI scanning was implemented with a 3.0-T MRI system. T2-weighted imaging (T2WI) features of the thymus in fetuses were quantitatively investigated with DICOM images. Statistical analysis was done with the Chi-Square test, oneway ANOVA, and Student's t-test. RESULTS: There was heterogeneity in the morphology of the fetal thymus. FS T2-weighted TSE sequence clearly exhibited the microstructure of the fetal thymus. The thymus extensively showed a lobulated appearance. The central signal is much higher than the peripheral signal in each lobule. In addition, FS-T2WI images can clearly show the interlobular septum, which is filled with fluid and presents a linear high signal. The signal intensity of fetal thymus increased with gestational weeks. The diameter measured in a particular plane was highly correlated with gestational week. CONCLUSION: FS T2-weighted TSE sequence provides high-resolution images of the fetal thymus. The change in signal intensity, location, and two-dimensional diameter in a specific plane can be used as a research direction for the fetal thymus.

9.
J Am Chem Soc ; 146(6): 3764-3772, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38304977

RESUMEN

TiO2-supported Pt species have been widely applied in numerous critical reactions involving photo-, thermo-, and electrochemical-catalysis for decades. Manipulation of the state of the Pt species in Pt/TiO2 catalysts is crucial for fine-tuning their catalytic performance. Here, we report an interesting discovery showing the epitaxial growth of PtO2 atomic layers on rutile TiO2, potentially allowing control of the states of active Pt species in Pt/TiO2 catalysts. The presence of PtO2 atomic layers could modulate the geometric configuration and electronic state of the Pt species under reduction conditions, resulting in a spread of the particle shape and obtaining a Pt/PtO2/TiO2 structure with more positive valence of Pt species. As a result, such a catalyst exhibits exceptional electrocatalytic activity and stability toward hydrogen evolution reaction, while also promoting the thermocatalytic CO oxidation, surpassing the performance of the Pt/TiO2 catalyst with no epitaxial structure. This novel epitaxial growth of the PtO2 structure on rutile TiO2 in Pt/TiO2 catalysts shows its potential in the rational design of highly active and economical catalysts toward diverse catalytic reactions.

10.
Mol Neurodegener ; 19(1): 1, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172904

RESUMEN

Triggering receptor expressed on myeloid cells 2 (TREM2) plays a critical role in microglial activation, survival, and apoptosis, as well as in Alzheimer's disease (AD) pathogenesis. We previously reported the MS4A locus as a key modulator for soluble TREM2 (sTREM2) in cerebrospinal fluid (CSF). To identify additional novel genetic modifiers of sTREM2, we performed the largest genome-wide association study (GWAS) and identified four loci for CSF sTREM2 in 3,350 individuals of European ancestry. Through multi-ethnic fine mapping, we identified two independent missense variants (p.M178V in MS4A4A and p.A112T in MS4A6A) that drive the association in MS4A locus and showed an epistatic effect for sTREM2 levels and AD risk. The novel TREM2 locus on chr 6 contains two rare missense variants (rs75932628 p.R47H, P=7.16×10-19; rs142232675 p.D87N, P=2.71×10-10) associated with sTREM2 and AD risk. The third novel locus in the TGFBR2 and RBMS3 gene region (rs73823326, P=3.86×10-9) included a regulatory variant with a microglia-specific chromatin loop for the promoter of TGFBR2. Using cell-based assays we demonstrate that overexpression and knock-down of TGFBR2, but not RBMS3, leads to significant changes of sTREM2. The last novel locus is located on the APOE region (rs11666329, P=2.52×10-8), but we demonstrated that this signal was independent of APOE genotype. This signal colocalized with cis-eQTL of NECTIN2 in the brain cortex and cis-pQTL of NECTIN2 in CSF. Overexpression of NECTIN2 led to an increase of sTREM2 supporting the genetic findings. To our knowledge, this is the largest study to date aimed at identifying genetic modifiers of CSF sTREM2. This study provided novel insights into the MS4A and TREM2 loci, two well-known AD risk genes, and identified TGFBR2 and NECTIN2 as additional modulators involved in TREM2 biology.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/patología , Receptor Tipo II de Factor de Crecimiento Transformador beta/genética , Estudio de Asociación del Genoma Completo , Microglía/patología , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquídeo , Glicoproteínas de Membrana/genética , Receptores Inmunológicos/genética
11.
Sci Rep ; 14(1): 1676, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243034

RESUMEN

Water resources protection is related to the development of the social economy, and the monitoring and prediction of water environmental indicators have important practical significance. In view of the seasonality, periodicity, uncertainty, and nonlinear characteristics of water quality indicators data, traditional prediction models have poor performance. To address this issue, this paper introduces a hybrid water quality index prediction model based on Ensemble Empirical Mode Decomposition (EEMD), combined with Convolutional Neural Network (CNN) and Bidirectional Long Short-Term Memory Network (BiLSTM). We have conducted out experiments to predict dissolved oxygen based on the water quality monitoring indicators of the Liaohe National Control Sanhongcun Village station in Yichun City. The results show that the model proposed in this paper improves the [Formula: see text] index by 5%, 7% and 5% compared to the suboptimal model in the 4-h, 1-day and 2-day index predictions, respectively.

12.
Sci Rep ; 14(1): 743, 2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38185699

RESUMEN

In practical engineering, the working conditions of gearbox are complex and variable. In varying working conditions, the performance of intelligent fault diagnosis model is degraded because of limited valid samples and large data distribution differences of gearbox signals. Based on these issues, this research proposes a gearbox fault diagnosis method integrated with lightweight channel attention mechanism, and further realizes the cross-component transfer learning. First, time-frequency distribution of original signals is obtained by wavelet transform. It could intuitively reflect local characteristics of signals. Secondly, based on a local cross-channel interaction strategy, a lightweight efficient channel attention mechanism (LECA) is designed. The kernel size of 1D convolution is affected by channel number and coefficients. Multi-scale feature input is used to retain more detailed features of different dimensions. A lightweight convolutional neural network is constructed. Finally, a transfer learning method is applied to freeze lower structures of the network and fine-tune higher structures of the model using small samples. Through experimental verification, the proposed model could effectively utilize samples. The application of transfer learning could realize accurate and fast fault classification of small samples, and achieve good gearbox fault diagnosis effect under varying working conditions and cross-component conditions.

13.
Plants (Basel) ; 13(2)2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38256714

RESUMEN

The expansion and intensification of coastal aquaculture around the Bohai Sea in China has reduced the tidal flats and damaged the coastal vegetation environment. However, there are few studies on the relationship between the evolution of coastal aquaculture and the variability of coastal vegetation, which limits our understanding of the impact of human activities on the coastal ecosystem. In this study, based on remote sensing technology, we firstly used a combination of a neural network classifier and manual correction to monitor the long-term dynamic changes in aquaculture in the Bohai Sea from 1984 to 2022. We then analyzed its evolution, as well as the relationship between the evolution of coastal aquaculture and the variability of coastal vegetation, in detail. Our study had three main conclusions. Firstly, the aquaculture along the coast of the Bohai Sea showed an expanding trend from 1984 to 2022, with an increase of 538%. Secondly, the spatiotemporal changes in the aquaculture centroids in different provinces and cities varied. The centroid of aquaculture in Liaoning Province was mainly distributed in the Liaodong Peninsula, and moved northwest; that in Hebei Province was distributed in the northeast and moved with no apparent pattern; the centroid of aquaculture in Tianjin was mainly distributed in the southeast and moved westward; and the centroid of aquaculture in Shandong Province was mainly distributed in the northwest and moved in a northwesterly direction. Finally, the expansion of aquaculture of the Bohai Sea has increased the regional NDVI and length of the corresponding coastline, and has made coastlines move toward the sea. Our results provide reliable data support and reference for ecologically managing aquaculture and coastal environmental protection in the Bohai Sea.

14.
Plants (Basel) ; 13(2)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38256766

RESUMEN

The coastal wetlands in the Yellow River Delta play a vital role in the ecological function of the area. However, the impact of primary restoration on microbial communities is not yet fully understood. Hence, this study aimed to analyze the bacterial and archaeal communities in the soil. The results indicated that Marinobacter and Halomonas were predominant in the bacterial community during spring and winter. On the other hand, Muribaculaceae and Helicobacter were prevalent during the core remediation of soil, while Inhella and Halanaerobium were predominant in non-vegetation-covered high-salinity soil. The bacterial Shannon index showed significant differences in vegetation-covered areas. For archaea, Salinigranum, Halorubrum, and Halogranum were dominant in vegetation areas, while Halolamina, Halogranum, and Halorubrum were prevalent in non-vegetation areas. The colonization of Suaeda salsa led to differences in the composition of bacteria (22.6%) and archaea (29.5%), and salt was one of the significant reasons for this difference. The microflora was more diverse, and the elements circulated after vegetation grounding, while the microbial composition in non-vegetation areas was similar, but there was potential competition. Therefore, vegetation restoration can effectively restore soil ecological function, while the microorganisms in the soil before restoration provide germplasm resources for pollutant degradation and antimicrobial development.

15.
Plant Physiol Biochem ; 206: 108257, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38064900

RESUMEN

Ocean warming (OW) and ocean acidification (OA), driven by rapid global warming accelerating at unprecedented rates, are profoundly impacting the stability of seagrass ecosystems. Yet, our current understanding of the effects of OW and OA on seagrass remains constrained. Herein, we investigated the response of eelgrass (Zostera marina L.), a representative seagrass species, to OW and OA through comprehensive transcriptomic and metabolomic analyses. The results showed notable variations in plant performance under varying conditions: OW, OA, and OWA (a combination of both conditions). Specifically, under average oceanic temperature conditions for eelgrass growth over the past 20 years -from May to November-OA promoted the production of differentially expressed genes and metabolites associated with alanine, aspartate, and glutamate metabolism, as well as starch and sucrose metabolism. Under warming condition, eelgrass was resistant to OA by accelerating galactose metabolism, along with glycine, serine, and threonine metabolism, as well as the tricarboxylic acid (TCA) cycle. Under the combined OW and OA condition, eelgrass stimulated fructose and mannose metabolism, glycolysis, and carbon fixation, in addition to galactose metabolism and the TCA cycle to face the interplay. Our findings suggest that eelgrass exhibits adaptive capacity by inducing different metabolites and associated genes, primarily connected with carbon and nitrogen metabolism, in response to varying degrees of OW and OA. The data generated here support the exploration of mechanisms underlying seagrass responses to environmental fluctuations, which hold critical significance for the future conservation and management of these ecosystems.


Asunto(s)
Agua de Mar , Zosteraceae , Ecosistema , Zosteraceae/fisiología , Concentración de Iones de Hidrógeno , Galactosa , Océanos y Mares
16.
Int J Biol Macromol ; 254(Pt 3): 127929, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37972844

RESUMEN

An antibacterial carbon dot hydrogel (GDSS-PCD) was constructed based on gelatin, dialdehyde starch (DS) and carbon dots (S-PCDs). The formation mechanism of GDSS-PCD hydrogels was attributed to the synergistic cross-linking of hydrogen bonds and dynamic covalent bonds. With increasing S-PCD content, the mechanical and rheological properties of GDSS-PCD hydrogels can be improved, and the micropore size becomes denser. GDSS-PCD hydrogels had pH-dependent swelling and degradation behavior, with a high swelling rate under acidic conditions and relatively low swelling under neutral and alkaline conditions. The cumulative release of S-PCDs from the same hydrogel in an acidic environment was higher than that in an alkaline environment, indicating that the GDSS-PCD hydrogel had a pH-dependent controlled release ability. The release behavior of S-PCDs conformed to the first-order kinetic release model (R2 > 0.95), and the release mechanism was related to Fickian diffusion. The synergistic antibacterial mechanism of GDSS-PCD hydrogels against Staphylococcus aureus suggested that bacterial metabolism leads to an acidic culture environment, which releases S-PCDs and destroys the bacterial cell membrane for antibacterial purposes. In GDSS-PCD hydrogels, S-PCDs play the main antibacterial role, and the hydrogel plays a synergistic role in trapping bacteria. Carbon dot hydrogels are promising materials to fulfil the functions of antibacterial and controlled release in the food and biomedical fields.


Asunto(s)
Gelatina , Hidrogeles , Hidrogeles/farmacología , Hidrogeles/química , Gelatina/química , Carbono , Preparaciones de Acción Retardada/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Concentración de Iones de Hidrógeno
17.
Adv Mater ; 36(7): e2310270, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38014758

RESUMEN

While cost-effective sodium-ion batteries (SIBs) with crystalline silicon anodes promise high theoretical capacities, they perform poorly because silicon stores sodium ineffectively (capacity <40 mAh g-1 ). To address this issue, herein an atomic-order structural-design tactic is adopted for obtaining unique multilevel gradient-ordered silicon (MGO-Si) by simple electrochemical reconstruction. In situ-formed short-range-, medium-range-, and long-range-ordered structures construct a stable MGO-Si, which contributes to favorable Na-Si interaction and fast ion diffusion channels. These characteristics afford a high reversible capacity (352.7 mAh g-1 at 50 mA g-1 ) and stable cycling performance (95.2% capacity retention after 4000 cycles), exhibiting record values among those reported for pure silicon electrodes. Sodium storage of MGO-Si involves an adsorption-intercalation mechanism, and a stepwise construction strategy of gradient-ordered structure further improves the specific capacity (339.5 mAh g-1 at 100 mA g-1 ). Reconstructed Si/C composites show a high reversible capacity of 449.5 mAh g-1 , significantly better than most carbonaceous anodes. The universality of this design principle is demonstrated for other inert or low-capacity materials (micro-Si, SiO2 , SiC, graphite, and TiO2 ), boosting their capacities by 1.5-6 times that of pristine materials, thereby providing new solutions to facilitate sodium storage capability for better-performing battery designs.

18.
Environ Sci Pollut Res Int ; 30(56): 118396-118409, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37910368

RESUMEN

China's Yellow River, the nation's second-longest, grapples with severe water scarcity, impeding the high-quality development of its basin. Our study meticulously examines the intricate virtual water trade network inside and outside the basin, providing essential insights to combat its acute water scarcity. We calculated water consumption coefficients for seven pivotal sectors across diverse Chinese provinces, forming the foundational data for quantifying virtual water trade both inside and outside the basin. Utilizing the 2015 Multi-Regional Input-Output Table, we assessed the Yellow River Basin's reliance on external water resources. Despite enduring chronic water scarcity, the basin annually exports a substantial 27.2 billion m3 of virtual water, equivalent to half of its yearly runoff. This outflow predominantly flows to the economically advanced eastern coastal region, with Agriculture and Manufacturing sectors dominating. Significantly, an irrational industrial layout leads to a substantial transfer of virtual water from economically disadvantaged areas to more affluent regions, exacerbating water scarcity in the basin's less privileged areas. Our study yields critical insights for mitigating water shortages in the Yellow River Basin and provides a transferrable framework for regions worldwide grappling with analogous challenges.


Asunto(s)
Abastecimiento de Agua , Agua , Ríos , Inseguridad Hídrica , China
19.
Mar Pollut Bull ; 197: 115815, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37984090

RESUMEN

The nutrients such as dissolved inorganic nitrogen (DIN, NH4+-N, NO2--N, and NO3--N), dissolved inorganic phosphorus (DIP, PO43-) and dissolved SiO2 (DSi) funneled by the inlet river are the dominant factors to coastal eutrophication. This study investigated nutrient transport process in typical inlet rivers in the Yellow River Delta. The indicator of coastal eutrophication potential and concentration ratio between upstream and downstream stations were used to evaluate the influence of different sources to the nutrient risks. It showed that urban areas are the most important source of the nutrients in studied rivers. The harbor and mariculture would have greater risk because of their proximity close to the coastal area. Wetland was a vital conversion to eliminate the river nutrients, and the retention could reach 80 %. It is imperative to protect and construct wetlands to reduce the nutrient pollution in the inlet river.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Bahías , Dióxido de Silicio , Eutrofización , Nutrientes , Nitrógeno/análisis , Fósforo/análisis , China
20.
Nat Commun ; 14(1): 6202, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794008

RESUMEN

The incentive-based emergency demand response measure serves as an important regulatory tool during energy system operations. However, whether people will sacrifice comfort to respond to it during heatwave and what the effect on heat vulnerable populations will be are still unclear. A large-scale emergency demand response pilot involving 205,129 households was conducted in southwestern China during continuous extreme high temperatures in summer. We found that the incentive-based emergency demand response causes a statistically significant decline in electricity use with no additional financial burden on vulnerable groups. The electricity conservation potential of urban households was higher than that of rural households. Households with children did not respond to the emergency demand response, while the response of households with elderly individuals proved to be more positive. The repeated and frequent implementation of this policy did not result in an attenuation of the regulatory effect. This research can serve as a reference for countries with similar regulated power markets.


Asunto(s)
Calor , Motivación , Niño , Humanos , Anciano , Estaciones del Año , China , Población Rural
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