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1.
J Colloid Interface Sci ; 674: 686-694, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38950467

RESUMEN

The energy storage capacity of porous carbon materials is closely tied to their surface structure and chemical properties. However, developing an innovative and straightforward approach to synthesize yolk-shell carbon spheres (YCs) remains a great challenge till date. Herein, we prepared a series of porous nitrogen-doped yolk-shell carbon spheres (NYCs) via a "pyrolysis-capture" method. This method involves coating the resorcinol-formaldehyde (RF) resin sphere with a layer of compact silica shell induced by 2-methylimidazole (ME) catalysis to produce a confined nano-space. Based on the confined effect of compact silica shell, volatile gases emitted from the RF resin and ME during pyrolysis can not only diffuse into the pores of the RF resin but can also be captured to form an outer carbon shell. This results in the tunable structures of NYCs materials. As the pyrolysis temperature rises, the shell thickness of NYCs reduces, the pore size expands, the roughness increases, and the N/O content of surface elements is enhanced. Notably, as an electrode material used forsupercapacitors,the optimized NYCs-800 exhibits excellent performance with a capacitance of 301.2F g-1 at the current density of 1 A/g and outstanding cycling life stability of 96.1% after 10,000 cycles. These results signify that controlling the surface structure and chemical properties of NYCs materials is an effective approach for constructing advanced energy storage materials.

2.
J Hazard Mater ; 476: 134970, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38905977

RESUMEN

As a crucial sink of metal-containing nanoparticles (MNPs), road dust can record their spatiotemporal variations in urban environments. In this study, taking Shanghai as a representative megacity in China, a total of 272 dust samples were collected in the winter and summer of 2013 and 2021/2022 to understand the spatiotemporal variations and driving factors of MNPs. The number concentrations of Fe-, Ti-, and Zn-containing NPs were 3.8 × 106 - 8.4 × 108, 2.3 × 106-1.4 × 108, and 6.0 × 105-2.3 × 108 particles/mg, respectively, according to single particle (sp)ICP-MS analysis. These MNPs showed significantly higher number concentrations in summer than in winter. Hotspots of Fe-containing NPs were more concentrated in industrial and traffic areas, Zn-containing NPs were mainly distributed in the central urban areas, while Ti-containing NPs were abundant in areas receiving high rainfall. The structural equation model results indicates that substantial rainfall in summer can help remove MNPs from atmospheric PM2.5 into dust, while in winter industrial and traffic activities were the primary contributors for MNPs. Moreover, the contribution of traffic emissions to MNPs has surpassed industrial one over the last decade, highlighting the urgency to control traffic-sourced MNPs, especially those from non-exhaust emissions by electric vehicles.

3.
Mar Pollut Bull ; 205: 116642, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38941803

RESUMEN

Since the Industrial Revolution, increasing atmospheric CO2 concentrations have had a substantial negative impact influence on coastal ecosystems because of direct effects including ocean acidification and indirect effects such as extreme rainfall events. Using a two-factor crossover indoor simulation experiment, this study examined the combined effects of acidification and hyposaline stress on Thalassia hemprichii. Seawater acidification increased the photosynthetic pigment content of T. hemprichii leaves and promoted seagrass growth rate. Hyposaline stress slowed down seagrass growth and had an impact on the osmotic potential and osmoregulatory substance content of seagrass leaves. Acidification and salinity reduction had significant interaction effects on the photosynthesis rate, photosynthetic pigment content, chlorophyll fluorescence parameters, and osmotic potential of T. hemprichii, but not on the growth rate. Overall, these findings have shown that the hyposaline stress inhibitory effect on the T. hemprichii physiological performance and growth may be reduced by acidification.

4.
Inorg Chem ; 63(23): 10786-10797, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38772008

RESUMEN

To date, developing crystalline proton-conductive metal-organic frameworks (MOFs) with an inherent excellent proton-conducting ability and structural stability has been a critical priority in addressing the technologies required for sustainable development and energy storage. Bearing this in mind, a multifunctional organic ligand, 3,4-dimethylthiophene[2,3-b]thiophene-2,5-dicarboxylic acid (H2DTD), was employed to generate two exceptionally stable three-dimensional porous Zr/Hf MOFs, [Zr6O4(OH)4(DTD)6]·5DMF·H2O (Zr-DTD) and [Hf6O4(OH)4(DTD)6]·4DMF·H2O (Hf-DTD), using solvothermal means. The presence of Zr6 or Hf6 nodes, strong Zr/Hf-O bonds, the electrical influence of the methyl group, and the steric effect of the thiophene unit all contribute to their structural stability throughout a wide pH range as well as in water. Their proton conductivity was fully examined at various relative humidities (RHs) and temperatures. Creating intricate and rich H-bonded networks between the guest water molecules, coordination solvent molecules, thiophene-S, -COOH, and -OH units within the framework assisted proton transfer. As a result, both MOFs manifest the maximum proton conductivity of 0.67 × 10-2 and 4.85 × 10-3 S·cm-1 under 98% RH/100 °C, making them the top-performing proton-conductive Zr/Hf-MOFs. Finally, by combining structural characteristics and activation energies, potential proton conduction pathways for the two MOFs were identified.

5.
Heliyon ; 10(10): e31226, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38799747

RESUMEN

Sea level fall is considered one of the significant factors leading to the end-Permian mass extinction (EPME). We studied the relative sea level changes in the Beifengjing and Shangsi sections, and the results indicate that a sea level fall occurred in the Upper Yangtze region during the Permian-Triassic transition. Considering that there is no significant change in fossil abundance in the strata following the two sea level falls observed in the Beifengjing section, we conclude that the reduction in shallow marine habitat for sea level fall solely was insufficient to cause the mass extinction. However, sea level fall did exacerbate the input of terrestrial debris into the ocean, leading to the deterioration of the marine environment. We propose that the combined adverse effects of volcanic eruptions, sea level falls, and other events exceeded the threshold for biological survival, ultimately resulting in the catastrophic EPME.

6.
Inorg Chem ; 63(18): 8194-8205, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38639416

RESUMEN

Although crystalline metal-organic frameworks (MOFs) have gained a great deal of interest in the field of proton conduction in recent years, the low stability and poor proton conductivity (σ) of some MOFs have hindered their future applications. As a result, resolving the issues listed above must be prioritized. Due to their exceptional structural stability, MOFs with ferrocene groups that exhibit particular physical and chemical properties have drawn a lot of attention. This study describes the effective preparation of a set of three-dimensional ferrocene-based MOFs, MIL-53-FcDC-Al/Ga and CAU-43, containing both main group metals and 1,1'-ferrocene dicarboxylic acid (H2FcDC). Multiple measurements, including powder X-ray diffraction (PXRD), infrared (IR), and scanning electron microscopy (SEM), confirmed that the addition of ferrocene groups enhanced the thermal, water, and acid-base stabilities of the three MOFs. Consequently, their proton-conductive behaviors were meticulously measured utilizing the AC impedance approach, and their best proton conductivities are 5.20 × 10-3, 2.31 × 10-3, and 1.72 × 10-4 S/cm at 100 °C/98% relative humidity (RH), respectively. Excitingly, MIL-53-FcDC-Al/Ga demonstrated an extraordinarily ultrahigh σ of above 10-4 S·cm-1 under 30 °C/98% RH. Using data from structural analysis, PXRD, SEM, thermogravimetry (TG), and activation energy, their proton transport mechanisms were thoroughly examined. The fact that these MOFs are notably easy to assemble, inexpensive, toxin-free, and stable will increase the range of practical uses for them.

7.
ACS Appl Mater Interfaces ; 16(11): 13745-13755, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38446712

RESUMEN

Currently, it is still a challenge to directly achieve highly stable metal-organic frameworks (MOFs) with superior proton conductivity solely through the exquisite design of ligands and the attentive selection of metal nodes. Inspired by this, we are intrigued by a multifunctional dicarboxylate ligand including dithiophene groups, 3,4-dimethylthieno[2,3-b]thiophene-2,5-dicarboxylic acid (H2DTD), and lanthanide ions with distinct coordination topologies. Successfully, four isostructural three-dimensional lanthanide(III)-based MOFs, [Ln2(DTD)3(DEF)4]·DEF·6H2O [LnIII = TbIII (Tb-MOF), EuIII (Eu-MOF), SmIII (Sm-MOF), and DyIII (Dy-MOF)], were solvothermally prepared, in which the effective proton transport will be provided by the coordinated or free solvent molecules, the crystalline water molecules, and the framework components, as well as a large number of highly electronegative S and O atoms. As expected, the four Ln-MOFs demonstrated the highest proton conductivities (σ) being 0.54 × 10-3, 3.75 × 10-3, 1.28 × 10-3, and 1.92 × 10-3 S·cm-1 for the four MOFs, respectively, at 100 °C/98% relative humidity (RH). Excitingly, Dy-MOF demonstrated an extraordinary ultrahigh σ of 1 × 10-3 S·cm-1 at 30 °C/98% RH. Additionally, the plausible proton transport mechanisms were emphasized.

8.
J Colloid Interface Sci ; 665: 554-563, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38552572

RESUMEN

The achievement of covalent organic frameworks (COFs) with high stability and exceptional proton conductivity is of tremendous practical importance and challenge. Given this, we hope to prepare the highly stable COFs carrying CN connectors and enhance their proton conductivity via a post-modification approach. Herein, one COF, TpTta, was successfully synthesized by employing 1,3,5-triformylphloroglucinol (Tp) and 4,4',4″-(1,3,5-triazine-2,4,6-triyl)-trianiline (Tta) as starting materials, which has a ß-ketoenamine structure bearing a large amount of -NH groups and intramolecular H-bonds. TpTta was then post-modified by inserting imidazole (Im) and histamine (His) molecules, yielding the corresponding COFs, Im@TpTta and His@TpTta, respectively. As a result, their proton conductivities were surveyed under changeable temperatures (30-100 °C) and relative humidities (68-98 %), revealing a degree of temperature and humidity dependence. Impressively, under identical conditions, the optimum proton conductivities of the two post-modified COFs are 1.14 × 10-2 (Im@TpTta) and 3.45 × 10-3 S/cm (His@TpTta), which are significantly greater than that of the pristine COF, TpTta (2.57 × 10-5 S/cm). Finally, their proton conduction mechanisms were hypothesized based on the computed activation energy values, water vapor adsorption values, and structural properties of these COFs. Additionally, the excellent electrochemical stability of the produced COFs was expressed, as well as the prospective application value.

9.
Int J Surg ; 110(3): 1527-1536, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38116673

RESUMEN

BACKGROUND: Triple-negative breast cancer (TNBC) is associated with a dismal prognosis. Immune checkpoint inhibitors have shown promising antitumor activity in neoadjuvant settings. This single-arm, phase II trial aimed to evaluate the efficacy and safety of camrelizumab plus chemotherapy as the neoadjuvant therapy (NAT) in early TNBC. METHODS: Patients received eight cycles of camrelizumab plus nonplatinum-based chemotherapy. The primary endpoint was total pathological complete response (pCR). Secondary endpoints included the breast pathological complete response (bpCR), adverse events (AEs). Multiomics biomarkers were assessed as exploratory objective. RESULTS: Twenty of 23 TNBC patients receiving NAT underwent surgery, with the total pCR rate of 65% (13/20) and bpCR rate of 70% (14/20). Grade ≥3 treatment-related AEs were observed in 14 (60.9%) patients, with the most common AE being neutropenia (65.2%). Tumor immune microenvironment was analyzed between pCR and non-pCR samples before and after the NAT. Gene expression profiling showed a higher immune infiltration in pCR patients than non-pCR patients in pre-NAT samples. Through establishment of a predictive model for the NAT efficacy, TAP1 and IRF4 were identified as the potential predictive biomarkers for response to the NAT. Gene set enrichment analysis revealed the glycolysis and hypoxia pathways were significantly activated in non-pCR patients before the NAT, and this hypoxia was aggravated after the NAT. CONCLUSION: Camrelizumab plus nonplatinum-based chemotherapy shows a promising pCR rate in early-stage TNBC, with an acceptable safety profile. TAP1 and IRF4 may serve as potential predictive biomarkers for response to the NAT. Aggravated hypoxia and activated glycolysis after the NAT may be associated with the treatment resistance.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Neoplasias de la Mama Triple Negativas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Hipoxia/tratamiento farmacológico , Hipoxia/etiología , Terapia Neoadyuvante , Proyectos Piloto , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Microambiente Tumoral , Femenino
10.
Environ Sci Pollut Res Int ; 30(51): 110612-110622, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37792195

RESUMEN

The increased copper ion (Cu2+) concentrations in aquatic ecosystem significantly influence the environmental quality and ecosystem safety, while information on the Cu2+ biotoxicity to aquatic microorganisms and the models for biotoxicity prediction are still unclear. In this study, the toxicities of Cu2+ to Chlorella vulgaris under different environmental conditions (e.g., Na+, K+, Ca2+, Mg2+, pH, and dissolved organic matter) were explored, with the experimental results in comparison with those predicted by the biotic ligand model (BLM). Results showed that increased Cu2+ concentration caused obvious toxicities to C. vulgaris, whereas the commonly occurring cations and dissolved organic matters can protect the metabolism system of C. vulgaris. The presence of extracellular polymeric substances (EPS) matrix can alleviate the biotoxicity via increasing the surface biosorption but decreasing cell internalization of Cu2+ in C. vulgaris. Due to the presence of EPS matrix, the experimental biotoxicity results under each condition were significantly lower than those predicted by the BLM model, which was thus modified via taking the EPS matrix as the supplement of allochthonous organic matters. After that, the modified BLM was characterized with a higher degree of precision and can be used in natural waters for biotoxicity prediction. Results obtained can enhance our insights into the ecological effects and biotoxicity prediction of heavy metals in natural aquatic ecosystems.


Asunto(s)
Chlorella vulgaris , Metales Pesados , Cobre/toxicidad , Ecosistema , Ligandos
11.
Infect Drug Resist ; 16: 6807-6820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37904831

RESUMEN

Purpose: This paper aims to investigate the effect of Tounong San (TNS), a well-known traditional Chinese medicine prescription for suppurative infections, on the immune function. Methods: A suppurative infection model was established by injecting Staphylococcus aureus into subcutaneous tissue on the backs of rats. The expressions of CD68, CD163, CD31 and MPO in abscess tissues, phagocytosis rate and reactive oxygen species (ROS) of neutrophils in blood, phagocytosis function of peritoneal macrophages, and proliferation of blood lymphocytes, expression of IL-1, IL-6, CH50, TNF-α, IFN-γ, IgG, IgM in serum were detected at different time points. Results: On the 3rd day of medication, fibrinogen wrapped around the abscesses was visible in TNS groups, with an increase in new blood vessels and the expression of a large number of macrophages and neutrophils. On the 6th day, the pus of TNS groups diminished, and the number of new blood vessels reached its peak. On the 9th day, the abscesses disappeared in TNS groups, fewer new blood vessels, macrophages, and neutrophils were expressed, and more fibrocytes appeared and filled the original pus cavities. On the 3rd and 9th day of medication, the phagocytic rates of neutrophils and macrophages were significantly improved in TNS group, and the ROS content of neutrophils was increased on the 9th day. TNS has no effect on lymphocyte proliferation in vitro, but it can regulate the secretion of IgG and IgM by lymphocytes. TNS increases the level of IL-1, decreases the levels of IL-6 and TNF-α, and regulates the expressions of IFN-γ and CH50 in two ways. Conclusion: TNS can form fibrinogen-wrapped pus to prevent bacterial infection from going deeper, and to improve the phagocytic function of phagocytes, the secretion of lymphocytes, and the defense function of the complement system. Therefore, it is a competitive drug for the treatment of suppurative diseases.

12.
Heliyon ; 9(8): e18488, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37593607

RESUMEN

Colorectal cancer (CRC) is the third most common cause of cancer-related morbidity worldwide, with an estimated of 1.85 million new cases and 850,000 deaths every year. Nevertheless, the current treatment regimens for CRC have many disadvantages, including toxicities and off-targeted side effects. STAT3 (signal transducer and activator of transcription 3) has been considered as a promising molecular target for CRC therapy. Brevilin A, a sesquiterpene lactone compound rich in Centipedae Herba has potent anticancer effects in nasopharyngeal, prostate and breast cancer cells by inhibiting the STAT3 signaling. However, the anti-CRC effect of brevilin A and the underlying mechanism of action have not been fully elucidated. In this study, we aimed to investigate the involvement of STAT3 signaling in the anti-CRC action of brevilin A. Here, HCT-116 and CT26 cell models were used to investigate the anti-CRC effects of brevilin A in vitro. HCT-116 cells overespressing with STAT3 were used to evaluate the involvement of STAT3 signaling in the anti-CRC effect of brevilin A. Screening of 49 phosphorylated tyrosine kinases in the HCT-116 cells after brevilin A treatment was performed by using the human phospho-receptor tyrosine kinase (phospho-RTK) array. Results showed that brevilin A inhibited cell proliferation and cell viability, induced apoptosis, reduced cell migration and invasion, inhibited angiogenesis, lowered the protein expression levels of phospho-Src (Tyr416), phospho-JAK2 (Y1007/1008) and phospho-STAT3 (Tyr705), and inhibited STAT3 activation and nuclear localization. Brevilin A also significantly reduced the protein expression levels of STAT3 target genes, such as MMP-2, VEGF and Bcl-xL. More importantly, over-activation of STAT3 diminished brevilin A's effects on cell viability. All these results suggest that brevilin A exerts potent anti-CRC effects, at least in part, by inhibiting STAT3 signaling. Our findings provide a strong pharmacological basis for the future exploration and development of brevilin A as a novel STAT3-targeting phytotherapeutic agent for CRC treatment.

13.
J Emerg Med ; 65(2): e93-e100, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37479639

RESUMEN

BACKGROUND: High-flow nasal cannula oxygen therapy (HFNC) is recommended for patients with COVID-19. However, the increasing use of HFNC brings a risk of delayed intubation. The optimal timing of switching from HFNC to invasive mechanical ventilation (IMV) remains unclear. An effective predictor is needed to assist in deciding on the timing of intubation. Respiratory rate and oxygenation (ROX) index, defined as (SpO2/FiO2) / respiratory rate, has already shown good diagnostic accuracy. Modified ROX (mROX) index, defined as (PaO2 /FiO2) / respiratory rate, might be better than the ROX index in predicting HFNC failure. OBJECTIVE: The aim was to evaluate the predictive value of mROX for HFNC failure in patients with COVID-19. METHODS: Severe or critical patients with COVID-19 treated with HFNC were enrolled in two clinical centers. Laboratory indicators, respiratory parameters, and mROX index at 0 h and 2 h after initial HFNC were collected. Based on the need for IMV after HFNC initiation, the patients were divided into an HFNC failure group and an HFNC success group. The predictive value of mROX index for IMV was evaluated by the area under the receiver operating characteristic curve (AUROC) and logistic regression analysis. We performed Kaplan-Meier survival analysis using the log-rank test. RESULTS: Sixty patients with COVID-19 (mean ± SD age, 62.8 ± 14.1 years; 42 patients were male) receiving HFNC were evaluated, including 18 critical and 42 severe cases. A total of 33 patients had hypertension; 14 had diabetes; 17 had chronic cardiac disease; 11 had chronic lung disease; 13 had chronic kidney disease; and 17 had a history of stroke. The AUROC of mROX index at 2 h was superior to that of other respiratory parameters to predict the need for IMV (0.959; p < 0.001). At the mROX index cutoff point of 4.45, predicting HFNC failure reached the optimal threshold, with specificity of 94% and sensitivity of 92%. Logistic regression analysis showed that 2-h mROX index < 4.45 was a protective factor for IMV (odd radio 0.18; 95% CI 0.05-0.64; p = 0.008). In the HFNC failure group, the median time from HFNC to IMV was 22.5 h. The 28-day mortality of the late intubation patients (≥ 22.5 h) was higher than that of the early intubation patients (< 22.5 h) (53.8% vs. 8.3%; p = 0.023). CONCLUSIONS: mROX at 2 h is a good early warning index of the need for IMV in patients with COVID-19 after HFNC initiation. Early intubation may lead to better survival in patients with 2-h mROX index < 4.45.


Asunto(s)
COVID-19 , Cánula , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Frecuencia Respiratoria , COVID-19/terapia , Terapia por Inhalación de Oxígeno , Intubación Intratraqueal
14.
J Sci Food Agric ; 103(15): 7664-7672, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37458104

RESUMEN

BACKGROUND: Nitrogen fertiliser is the major input and cost for wheat production, being required to support the development of the canopy to maximise yield and for the synthesis of the gluten proteins that are necessary for breadmaking. Consequently, current high-yielding cultivars require the use of nitrogen fertilisation levels above the yield optimum to achieve the grain protein content needed for breadmaking. This study aimed to reduce this requirement by identifying traits that allow the use of lower levels of nitrogen fertiliser to produce wheat for breadmaking. RESULTS: A range of commercial wheat genotypes (cultivars) were grown in multiple field trials (six sites over 3 years) in the UK with optimal (200 kg Ha-1 ) and suboptimal (150 kg Ha-1 ) application of nitrogen. Bulked grain samples from four sites per year were milled and white flours were baked using three types of breadmaking process. This identified five cultivars that consistently exhibited good breadmaking quality when grown with the lower nitrogen application. Chemical and biochemical analyses showed that the five cultivars were characterised by exhibiting grain protein deviation (GPD) and high dough elasticity. CONCLUSIONS: It is possible to develop novel types of wheat that exhibit good breadmaking quality by selecting for GPD and high dough strength. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Proteínas de Granos , Triticum/química , Nitrógeno/metabolismo , Fertilizantes , Pan/análisis , Fertilización
15.
Stem Cell Res ; 71: 103142, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37343430

RESUMEN

Alzheimer's disease (AD) is an age-related and progressive neurodegenerative disease. In this study, we generated an induced pluripotent stem cell (iPSC) line from the dermal fibroblasts of a 69-year-old female patient carrying APOEε3/ε4 allele and diagnosed with sporadic AD. The iPSC line will be a useful tool for investigating the pathogenesis mechanisms and for drug tests in AD.


Asunto(s)
Enfermedad de Alzheimer , Línea Celular , Células Madre Pluripotentes Inducidas , Enfermedades Neurodegenerativas , Anciano , Femenino , Humanos , Enfermedad de Alzheimer/patología , Pueblos del Este de Asia , Células Madre Pluripotentes Inducidas/metabolismo , Enfermedades Neurodegenerativas/metabolismo
16.
Small ; 19(25): e2207848, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36929269

RESUMEN

Polyvinyl pyrrolidone (PVP) is doped to PbI2 and organic salt during two-step growth of halideperovskite. It is observed that PVP molecules can interact with both PbI2 and organic salt, reduce the aggregation and crystallization of the two, and then slow down the coarsening rate of perovskite. As doping concentration increases from 0 to 1 mM in organic salt, average crystallite size of perovskite decreases monotonously from 90 to 34 nm; Surface fluctuation reduces from 259.9 to 179.8 nm at first, and then increases; Similarly, surface roughness decreases from 45.55 to 26.64 nm at first, and then rises. Accordingly, a kind of "confinement effect" is resolved to crystallite growth and surface fluctuation/roughness, which helps to build compact and uniform perovskite film. Density of trap states (t-DOS) is cut down by ≈60% at moderate doping  (0.2 mM). Due to the "confinement effect", power conversion efficiency of perovskite solar cells is improved from 19.46 (±2.80) % to 21.50 (±0.99) %, and further improved to 24.11% after surface modification. Meanwhile, "confinement effect" strengthens crystallite/grain boundaries and improves thermal stability of both film and device. T80 of device increases to 120 h, compared to 50 h for reference ones.

17.
Int J Biol Macromol ; 236: 123972, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36906208

RESUMEN

Heavy haze-induced decreases in solar radiation represent an important factor that affects the structural properties of starch macromolecules. However, the relationship between the photosynthetic light response of flag leaves and the structural properties of starch remains unclear. In this study, we investigated the impact of light deprivation (60 %) during the vegetative-growth or grain-filling stage on the leaf light response, starch structure, and biscuit-baking quality of four wheat cultivars with contrasting shade tolerance. Shading decreased the apparent quantum yield and maximum net photosynthetic rate of flag leaves, resulting in a lower grain-filling rate and starch content and higher protein content. Shading decreased the starch, amylose, and small starch granule amount and swelling power but increased the larger starch granule amount. Under shade stress, the lower amylose content decreased the resistant starch content while increasing the starch digestibility and estimated glycemic index. Shading during the vegetative-growth stage increased starch crystallinity, 1045/1022 cm-1 ratio, starch viscosity, and the biscuit spread ratio, while shading during the grain-filling stage decreased these values. Overall, this study indicated that low light affects the starch structure and biscuit spread ratio by regulating the photosynthetic light response of flag leaves.


Asunto(s)
Almidón , Triticum , Almidón/metabolismo , Triticum/química , Amilosa/análisis , Fotosíntesis/fisiología , Grano Comestible/química , Hojas de la Planta/metabolismo
18.
Sci Total Environ ; 870: 161870, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-36731571

RESUMEN

The heavy metal Cd can cause severe toxicity on aquatic algae, but there are few studies on the cytotoxicity of heavy metal on algae based on synchrotron radiation technology. In this study, synchrotron radiation-based Fourier transform infrared spectromicroscopy (SR-FTIR) was used to characterize in vivo the toxic effects of Cd on Cosmarium sp. cells, emphasizing the influence of dissolved organic matter (DOM) on Cd toxicity. Results showed that, in the absence of DOM, obvious growth inhibition, cell volume reduction, and photosynthesis disruption could be observed with increasing Cd concentrations (0-500 µg/L). Based on the SR-FTIR imaging and functional group quantification, it was shown that the biosynthesis of biomolecules such as proteins, lipids, and carbohydrates was inhibited in algal cells. However, the addition of DOM caused significant heterogeneities in biomacromolecule biosynthesis that an increased biosynthesis of carbohydrates and structural lipids but an inhibited biosynthesis of proteins and storage lipids were observed. Furthermore, the correlation analysis and principal component analysis showed a good correlation between v(C-OH)/Amide II and biochemical parameters, indicating that changes of carbohydrates could be used as the biomarker to indicate the cytotoxicity of heavy metals to algal cells. These findings provide insight into the mechanisms of heavy metal cytotoxicity to aquatic algae and systematic cytotoxicity assessment under various aquatic conditions.


Asunto(s)
Chlorophyta , Metales Pesados , Cadmio/análisis , Materia Orgánica Disuelta , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Sincrotrones , Chlorophyta/metabolismo , Plantas/metabolismo , Carbohidratos , Lípidos
19.
Inorg Chem ; 62(4): 1377-1382, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36657984

RESUMEN

An alkene-bridged thioether ligand (L) was designed and used for its first study within a polyoxometalate (POM) hybrid system, and a POM-based copper(I)-alkene compound [(CuIL)2(PVMoVI12O40)]·(CuIL) (1) was isolated and characterized by X-ray crystallography. A unique alkene-coordinating N(η2-C═C)N mode of L is observed, and the Cu centers are captured by σ2,π-L in a pocket fashion, giving birth to discrete [CuIL]+ cations and [(CuIL)2(PVMoVI12)]- anions. The ionic crystal exhibits solubility in aprotic polar solvents, and the electrospray ionization mass spectrometry is used to explore the nature of species present in the solution. It is found that the whole cluster [PVMoVI12]3- is completely present, and all the main peaks can be assigned to different charged fragments of the same parent cluster.

20.
Ecotoxicol Environ Saf ; 249: 114426, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36525947

RESUMEN

BACKGROUND: Electronic cigarette (e-cig) use is increasing worldwide, especially among young individuals. Spirometry measures airflow obstruction and is the primary tool for diagnosing/monitoring respiratory diseases in clinical settings. This study aims to assess the effects of chronic e-cig exposure on spirometric traits, and directly compare to conventional combustible-cigarette (c-cig). METHODS: We employed an e- and c-cig aerosol generation system that resembled human smoking/vaping scenario. Fifty 6-week old C57BL/6 mice were equally divided into five groups and exposed to clean air (control), e-cig aerosol (low- and high-dose), and c-cig aerosol (low- and high-dose), respectively, for 10 weeks. Afterwards, growth trajectory, spirometry and pulmonary pathology were analyzed. RESULTS: Both e- and c-cig exposure slowed down growth and weight gain. Low dose e-cig exposure (1 h exposure per day) resulted in minimal respiratory function damage. At high dose (2 h exposure per day), e-cig exposure deteriorated 7 spirometry traits but by a smaller magnitude than c-cig exposure. For example, comparing to clean air controls, high dose e- and c-cig exposure increased inspiratory resistance by 24.3% (p = 0.026) and 66.7% (p = 2.6e-5), respectively. Low-dose e-cig exposure increased alveolar macrophage count but did not lead to airway remodeling. In contrast, even low-dose c-cig caused alveoli break down and thickening of the small airway, hallmarks of airway obstructive disease. CONCLUSIONS: We conducted well-controlled animal exposure experiments assessing chronic e-cig exposure's effects on spirometry traits. Further, mechanistic study characterized airway remodeling, alveolar tissue lesion and inflammation induced by e- and c-cig exposure. Our findings provided scientific and public health insights on e-cig's health consequences, especially in adolescent users.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Lesión Pulmonar , Productos de Tabaco , Humanos , Ratones , Animales , Adolescente , Remodelación de las Vías Aéreas (Respiratorias) , Ratones Endogámicos C57BL , Aerosoles y Gotitas Respiratorias , Lesión Pulmonar/inducido químicamente
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