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1.
Small ; : e2400641, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38989690

RESUMEN

Li-rich manganese-based cathode (LRMC) has attracted intense attention to developing advanced lithium-ion batteries with high energy density. However, LRMC is still plagued by poor cyclic stability, undesired rate capacity, and irreversible oxygen release. To address these issues, herein, a feasible polyvinylidene fluoride (PVDF)-assisted interface modification strategy is proposed for modulating the surface architecture and electronic conductivity of LRMC by intruding the F-doped carbon coating, spinel structure, and oxygen vacancy on the LRMC, which can greatly enhance the cyclic stability and rate capacity, and restrain the oxygen release for LRMC. As a result, the modified material delivers satisfactory cyclic performance with a capacity retention of 90.22% after 200 cycles at 1 C, an enhanced rate capacity of 153.58 mAh g-1 at 5 C and 126.32 mAh g-1 at 10 C, and an elevated initial Coulombic efficiency of 85.63%. Moreover, the thermal stability, electronic conductivity, and structure stability of LRMC are also significantly improved by the PVDF-assisted interface modification strategy. Therefore, the strategy of simultaneously modulating the surface architecture and the electronic conductivity of LRMC provides a valuable idea to improve the comprehensive electrochemical performance of LRMC, which offers a promising reference for designing LRMC with high electrochemical performance.

2.
Small ; : e2404285, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39073246

RESUMEN

The solar-driven overall water splitting (2H2O→2H2 + O2) is considered as one of the most promising strategies for reducing carbon emissions and meeting energy demands. However, due to the sluggish performance and high H2 cost, there is still a big gap for the current photocatalytic systems to meet the requirements for practical sustainable H2 production. Economic feasibility can be attained through simultaneously generating products of greater value than O2, such as hydrogen peroxide (H2O2, 2H2O→H2 + H2O2). Compared with overall water splitting, this approach is more kinetically feasible and generates more high-value products of H2 and H2O2. In several years, there has been an increasing surge in exploring the possibility and substantial progress has been achieved. In this review, a concise overview of the importance and underlying principles of PIWS is first provided. Next, the reported typical photocatalysts for PIWS are discussed, including commonly used semiconductors and cocatalysts, essential design features of these photocatalysts, and connections between their structures and activities, as well as the selected approaches for enhancing their stability. Then, the techniques used to quantify H2O2 and the operando characterization techniques that can be employed to gain a thorough understanding of the reaction mechanisms are summarized. Finally, the current existing challenges and the direction needing improvement are presented. This review aims to provide a thorough summary of the most recent research developments in PIWS and sets the stage for future advancements and discoveries in this emerging area.

3.
Inorg Chem ; 63(32): 15034-15043, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39058545

RESUMEN

Solar energy is an ideal clean and inexhaustible energy source. Solar-driven formic acid (FA) dehydrogenation is one of the promising strategies to address safety and cost issues related to the storage, transport, and distribution of hydrogen energy. For FA dehydrogenation, the O-H and C-H cleavages are the key steps, and developing a photocatalyst with the ability to break these two bonds is critical. In this work, both density functional theory (DFT) calculation and experimental results confirmed the positive synergistic effect between brookite and rutile TiO2 for O-H and C-H cleavage in HCOOH. Further, brookite TiO2 is beneficial to the generation of the •OH radical and significantly promotes C-H cleavage in formate. Under optimized conditions, the H2 production efficiency of FA dehydrogenation can reach up to 30.4 µmol·mg-1·h-1, which is the highest value compared with similar reported TiO2-based systems and over 1.7 times the reported highest value of Au0.75Pd0.25/TiO2 photocatalysts. More importantly, after more than 42 days (>500 h) of irradiation, the system still demonstrated high H2 production activity, indicating the potential for practical application. This work provides a valuable strategy to improve both the efficiency and stability of photocatalytic FA dehydrogenation under mild conditions.

4.
BMC Infect Dis ; 24(1): 442, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671376

RESUMEN

BACKGROUND: Urinary tract infection (UTI) is a common cause of sepsis. Elderly patients with urosepsis in intensive care unit (ICU) have more severe conditions and higher mortality rates owing to factors such as advanced age, immunosenescence, and persistent host inflammatory responses. However, comprehensive studies on nomograms to predict the in-hospital mortality risk in elderly patients with urosepsis are lacking. This study aimed to construct a nomogram predictive model to accurately assess the prognosis of elderly patients with urosepsis and provide therapeutic recommendations. METHODS: Data of elderly patients with urosepsis were extracted from the Medical Information Mart for Intensive Care (MIMIC) IV 2.2 database. Patients were randomly divided into training and validation cohorts. A predictive nomogram model was constructed from the training set using logistic regression analysis, followed by internal validation and sensitivity analysis. RESULTS: This study included 1,251 patients. LASSO regression analysis revealed that the Glasgow Coma Scale (GCS) score, red cell distribution width (RDW), white blood count (WBC), and invasive ventilation were independent risk factors identified from a total of 43 variables studied. We then created and verified a nomogram. The area under the receiver operating characteristic curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA) of the nomogram were superior to those of the traditional SAPS-II, APACHE-II, and SOFA scoring systems. The Hosmer-Lemeshow test results and calibration curves suggested good nomogram calibration. The IDI and NRI values showed that our nomogram scoring tool performed better than the other scoring systems. The DCA curves showed good clinical applicability of the nomogram. CONCLUSIONS: The nomogram constructed in this study is a convenient tool for accurately predicting in-hospital mortality in elderly patients with urosepsis in ICU. Improving the treatment strategies for factors related to the model could improve the in-hospital survival rates of these patients.


Asunto(s)
Mortalidad Hospitalaria , Unidades de Cuidados Intensivos , Nomogramas , Sepsis , Infecciones Urinarias , Humanos , Anciano , Femenino , Masculino , Infecciones Urinarias/mortalidad , Unidades de Cuidados Intensivos/estadística & datos numéricos , Sepsis/mortalidad , Anciano de 80 o más Años , Factores de Riesgo , Pronóstico , Curva ROC , Estudios Retrospectivos
5.
Bioorg Chem ; 143: 107044, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38134522

RESUMEN

Musashi1 and Musashi2 are RNA-binding proteins originally found in drosophila, in which they play a crucial developmental role. These proteins are pivotal in the maintenance and differentiation of stem cells in other organisms. Research has confirmed that the Musashi proteins are highly involved in cell signal-transduction pathways such as Notch and TGF-ß. These signaling pathways are related to the induction and development of cancers, such as breast cancer, leukemia, hepatoma and liver cancer. In this review we focus on how Musashi proteins interact with molecules in different signaling pathways in various cancers and how they affect the physiological functions of these pathways. We further illustrate the status quo of Musashi proteins-targeted therapies and predict the target RNA regions that Musashi proteins interact with, in the hope of exploring the prospect of the design of Musashi protein-targeted medicines.


Asunto(s)
Química Farmacéutica , Neoplasias , Humanos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Unión al ARN/metabolismo , Neoplasias/tratamiento farmacológico , ARN
7.
3D Print Addit Manuf ; 11(2): e675-e687, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38689912

RESUMEN

Three-dimensional (3D) concrete printing technology has been considered promising, attracting extensive attention in the engineering field. Multiwalled carbon nanotubes (MWCNTs) have been used as an additive to reinforce the cement-based material. However, the research on the 3D printed MWCNT-reinforced high-strength concrete is rare. This research is to study the mechanical properties and pore structure of MWCNT-reinforced reactive powder concrete (RPC) for 3D printing. In this research, the workability of the printed RPC mixture with MWCNTs was first tested to pass the criteria of 3D printing. Then, the enhancement effect of MWCNTs on the printed RPC was tested by mechanical properties after hardening. Meanwhile, strength-displacement curves were recorded. In addition, the pore structures of printed RPC were observed and analyzed by X-ray computed tomography (CT) images. The results show that 0.05 wt% MWCNTs have no effect on the workability of the printable RPC slurry. MWCNTs could enhance the mechanical properties of the printed RPC by filling the flaws inside the samples, increasing the viscosity of the RPC slurry and forming bridges between cracks. Besides, 0.05 wt% MWCNTs may cause the failure mode of the printed RPC from brittle failure to ductile failure. In addition, MWCNTs significantly reduced the porosity of the printed RPC by decreasing pores with a volume over 0.01 mm3. As CT images show, the interlayer zone (IZ) of the 3D printed RPC sample is prone to pores, and a higher volume fraction is evident. In particular, within the volume of IZs, the minimum volume fraction at the IZ of 3D printed RPC appears on sample with MWCNTs.

8.
J Thorac Dis ; 16(4): 2654-2667, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38738242

RESUMEN

Background and Objective: Obstructive sleep apnea (OSA) is a common chronic disorder characterized by repeated breathing pauses during sleep caused by upper airway narrowing or collapse. The gold standard for OSA diagnosis is the polysomnography test, which is time consuming, expensive, and invasive. In recent years, more cost-effective approaches for OSA detection based in predictive value of speech and snoring has emerged. In this paper, we offer a comprehensive summary of current research progress on the applications of speech or snoring sounds for the automatic detection of OSA and discuss the key challenges that need to be overcome for future research into this novel approach. Methods: PubMed, IEEE Xplore, and Web of Science databases were searched with related keywords. Literature published between 1989 and 2022 examining the potential of using speech or snoring sounds for automated OSA detection was reviewed. Key Content and Findings: Speech and snoring sounds contain a large amount of information about OSA, and they have been extensively studied in the automatic screening of OSA. By importing features extracted from speech and snoring sounds into artificial intelligence models, clinicians can automatically screen for OSA. Features such as formant, linear prediction cepstral coefficients, mel-frequency cepstral coefficients, and artificial intelligence algorithms including support vector machines, Gaussian mixture model, and hidden Markov models have been extensively studied for the detection of OSA. Conclusions: Due to the significant advantages of noninvasive, low-cost, and contactless data collection, an automatic approach based on speech or snoring sounds seems to be a promising tool for the detection of OSA.

9.
ACS Sens ; 9(6): 2979-2988, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38818754

RESUMEN

The development of a highly selective and trace-level gas sensing platform for detecting hydrogen sulfide (H2S) remains a formidable challenge. To solve this problem, Co-Mo multimetal oxide semiconductors are rationally tailored by employing metal organic frameworks (MOFs) as self-sacrificial templates. The MOF-derived Co3O4/ß-CoMoO4 based gas sensors displays high sensitivity (Rg/Ra = 22) to 10 ppm of H2S and ultralow limit of detection (10 ppb H2S). The formation of p-p heterojunction and multivalence states of Mo play a crucial role in electron transfer and oxygen adsorption. A sensor array constructed from four Co3O4/ß-CoMoO4 materials with different Co/Mo ratios demonstrates a superior selective discrimination of H2S from other VOCs and malodorous gases by principal component analysis (PCA). Besides, a H2S gas sensing and alarming platform was designed for monitoring the environment contaminated with H2S. This finding provides a feasible approach for the discovery of highly efficient gas sensors to monitor environmental H2S concentration.


Asunto(s)
Cobalto , Sulfuro de Hidrógeno , Estructuras Metalorgánicas , Molibdeno , Óxidos , Semiconductores , Sulfuro de Hidrógeno/análisis , Óxidos/química , Cobalto/química , Estructuras Metalorgánicas/química , Molibdeno/química , Límite de Detección
10.
J Hazard Mater ; 465: 133379, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38160555

RESUMEN

Ground-level ozone (O3) is a primary air pollutant with potential adverse impacts on human health and ecosystems. Aiming to detect O3 concentration and develop efficient O3 sensing materials, sensing behavior of heterogenous cation (Fe3+, Sn4+ and Sb5+) doped In2O3 nanostructures was investigated. The incorporation of these cations modulated the electronic structure of semiconductor oxides, affecting the density of chemisorbed oxygen species and reactive sites. From O3 sensing results, Fe3+ doped In2O3 based sensors featuring saturated resistance curves in O3 gas, demonstrated fast sensing speed and qualified detection threshold (20 ppb). In contrast, Sn4+ and Sb5+ doped counterparts exhibited non-saturated sensing curves, resulting in slower response/recovery speed. As a proof-of-concept, these optimized sensors were integrated as the sensor array. Coupled to the image recognition technique, this sensor array could successfully discriminate O3 and NOx. That is, through the tailored combination of material modulation and sensor array, this study paves a novel approach for highly sensitive and selective O3 detection.

11.
Anal Chim Acta ; 1285: 341996, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38057046

RESUMEN

A sensitive method for the detection of ß-glucuronidase was established using functionalized carbon dots (ß-CD-SiCDs) as fluorescent probes. The ß-CD-SiCDs were found to be obtained through in situ autopolymerization by mixing the solutions of methyldopa, mono-6-ethylenediamine-ß-cyclodextrin and N-(ß-aminoethyl)-γ-aminopropyltrimethoxysilane at room temperature. The method has the characteristics of low energy consumption, simple and rapid. ß-CD-SiCDs exhibited green fluorescence at 515 nm emission with a quantum yield of 7.9 %. 4-nitrophenyl-ß-D-glucuronide was introduced as a substrate for ß-glucuronidase to generate p-nitrophenol. Subsequently, p-nitrophenol self-assembled with ß-CD-SiCDs through host-guest recognition to form a stable inclusion complex, resulting in the fluorescence quenching of ß-CD-SiCDs. The linear range of ß-CD-SiCDs for detecting ß-glucuronidase activity was 0.5-60 U L-1 with a detection limit of 0.14 U L-1. For on-site detection, gel reagents were prepared by a simple method and the images were visualized and quantified by taking advantage of smartphones, avoiding the use of large instrumentation. The constructed fluorescence sensing platform has the benefits of easy operation and time saving, and has been successfully used for the detection of ß-glucuronidase activity in serum and cell imaging.


Asunto(s)
Ciclodextrinas , Puntos Cuánticos , Glucuronidasa , Carbono , Colorantes Fluorescentes
12.
J Gastrointest Oncol ; 15(1): 468-477, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38482229

RESUMEN

Background: Given the pivotal role of neuroinflammation in chronic pain and that the paraventricular nucleus of the hypothalamus (PVN) is a crucial brain region involved in visceral pain regulation, we sought to investigate whether the targeted modulation of microglia and astrocytes in the PVN could ameliorate pancreatic cancer-induced visceral pain (PCVP) in mice. Methods: Using a mouse model of PCVP, achieved by tumor cell injection at the head of the pancreas, we measure the number of glial cells, and at the same time we employed minocycline to inhibit microglia and chemogenetic methods to suppress astrocytes in order to investigate the respective roles of microglia and astrocytes within the PVN in PCVP. Results: Mice exhibited visceral pain at 12, 15 and 18 days post-tumor cell injection. We observed a significant increase in the population of both microglia and astrocytes. Inhibition of microglial activity through minocycline microinjection into the PVN resulted in alleviation of visceral pain within 30 and 60 min. Similarly, chemogenetic inhibition of astrocyte function at 14 and 21 days post-injection also led to relief from visceral pain. Conclusions: This study found that PVN microglia and astrocytes were involved in regulating PCVP. Our results suggest that targeting glia may be a potential approach for alleviating visceral pain in patients with pancreatic cancer.

13.
J Gastrointest Oncol ; 15(1): 458-467, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38482250

RESUMEN

Background: For patients with pancreatic cancer, visceral pain is a debilitating symptom that significantly compromises their quality of life. Unfortunately, the lack of effective treatment options can be attributed to our limited understanding of the neural circuitry underlying this phenomenon. The primary objective of this study is to elucidate the fundamental mechanisms governing visceral pain induced by pancreatic cancer in murine models. Methods: A mouse model of pancreatic cancer visceral pain was established in C57BL/6N mice through the intrapancreatic injection of mPAKPC-luc cells. Abdominal mechanical hyperalgesia and hunch score were employed to evaluate visceral pain, whereas the in vitro electrophysiological patch-clamp technique was utilized to record the electrophysiological activity of GABAergic neurons. Specific neuron ablation and chemogenetics methods were employed to investigate the involvement of GABAergic neurons in pancreatic cancer-induced visceral pain. Results: In vitro electrophysiological results showed that the firing frequency of GABAergic neurons in the paraventricular nucleus of the hypothalamus (PVN) was decreased. Specific destruction of GABAergic neurons in the PVN exacerbated visceral pain induced by pancreatic cancer. Chemogenetics activation of GABAergic neurons in the PVN alleviated visceral pain induced by pancreatic cancer. Conclusions: GABAergic neurons located in PVN play a crucial role in precipitating visceral pain induced by pancreatic cancer in mice, thereby offering novel insights for identifying effective targets to treat pancreatic cancer-related visceral pain.

14.
ACS Appl Mater Interfaces ; 16(9): 11349-11360, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38381529

RESUMEN

P2-type Fe-Mn-based oxides offer excellent discharge specific capacity and are as affordable as typical layered oxide cathode materials for sodium-ion batteries (SIBs). After Cu modification, though they can improve the cycling performance and air stability, the discharge specific capacity will be reduced. Considering the complementary nature of biphasic phases in electrochemistry, hybridizing P2/O3 hybrid phases can enhance both the storage performance of the battery and specific capacity. Herein, a hybrid phase composite with high capacity and good cycle performance is deliberately designed and successfully prepared by controlling the amount of Mg doping in the layered oxide. It has been found that the introduction of Mg can activate anion redox in the oxide layer, resulting in a significant increase in the specific discharge capacity of the material. Meanwhile, the dual-phase structure can produce an interlocking effect, thus effectively alleviating structure strain. The degradation of cycling performance caused by structural damage during the high-voltage charging and discharging process is clearly mitigated. The results show that the specific discharge capacity of Na0.67Cu0.2Mg0.1Fe0.2Mn0.5O2 is as high as 212.0 mAh g-1 at 0.1C rate and 186.2 mAh g-1 at 0.2C rate. After 80 cycles, the capacity can still maintain 88.1%. Moreover, the capacity and cycle performance as well as the stability can still remain stable even in the high-voltage window. Therefore, this work offers an insightful exploration for the development of composite cathode materials for SIBs.

15.
J Phys Chem Lett ; 15(26): 6750-6757, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38912792

RESUMEN

Colloidal quantum dots (CQDs) have garnered considerable attention for photodetectors (PDs), attributable to exceptional photoelectric properties and ease solution-based processing. However, the prevalent use of 1,2-ethanedithiol (EDT) as a hole transport layer (HTL) has limitations, such as energy level discrepancies, requisite oxidation, and intricate multilayer assembly. Organic p-type materials, lauded for their superior attributes and synthetic versatility, are now stepping forward as viable substitutes for conventional EDT HTLs. In this work, we introduced an organic HTL derived from indolo[3,2-b]carbazole, named ZL004, leading to a marked improvement in carrier generation and collection, facilitated by the optimized band alignment and enhanced interfacial charge dynamics. The ZL004-based PDs exhibit a photoresponsivity of 0.45 A/W, a noise current of 1.8 × 10-11 A Hz-0.5, a specific detectivity of 4.6 × 109 Jones, and an expansive linear dynamic range of 107 dB─surpassing EDT-based devices across the board, demonstrating the extraordinary property of organic p-type materials for CQD-based PDs.

16.
ACS Appl Mater Interfaces ; 16(27): 34880-34891, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38949126

RESUMEN

Lithium-rich manganese-based layered oxides (LRMOs) have recently attracted enormous attention on account of their remarkably big capacity and high working voltage. However, some inevitable inherent drawbacks impede their wide-scale commercial application. Herein, a kind of Cr-containing Co-free LRMO with a topical spinel phase (Li1.2Mn0.54Ni0.13Cr0.13O2) has been put forward. It has been found that the high valence of Cr6+ can reduce the Li+ ion content and induce the formation of a local spinel phase by combining more Li+ ions, which is beneficial to eliminate the phase boundary between the spinel phase and the bulk phase of the LRMO material, thus dramatically avoiding phase separation during the cycling process. In addition, the introduction of Cr can also expand the layer spacing and construct a stronger Cr-O bond compared with Mn-O, which enables to combine the transition metal (TM) slab to prevent the migration of TM ions and the transformation of the bulk phase to the spinel phase. Simultaneously, the synergistic effect of the successfully constructed spinel-layered biphase interface and the strong Cr-O bond can effectively impede the escape of lattice oxygen during the initial activation process of Li2MnO3 and provide the fast diffusion path for Li+ ion transmission, thus further reinforcing the configurable stability. Besides, Cr-LRMO presents an ultrahigh first discharge specific capacity of 310 mAh g-1, an initial Coulombic efficiency of as high as 92.09%, a good cycling stability (a capacity retention of 94.70% after 100 cycles at 1C), and a small voltage decay (3.655 mV per cycle), as well as a good rate capacity (up to 165.88 mAh g-1 at 5C).

17.
Chem Commun (Camb) ; 60(40): 5294-5297, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38659410

RESUMEN

We developed a triazatruxene-based hole transport material (HTM), 3Ka-DBT-3Ka, aiming to enhance band alignment and augment charge generation and collection in devices, as an alternative for 1,2-ethanedithiol (EDT). The PbS CQD solar cells employing 3Ka-DBT-3Ka as the HTM achieve a peak efficiency of 11.4%, surpassing devices employing the conventional PbS-EDT HTM (8.9%).

18.
Hepatobiliary Surg Nutr ; 13(2): 258-272, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38617474

RESUMEN

Background: Visceral pain induced by pancreatic cancer seriously affects patients' quality of life, and there is no effective treatment, because the mechanism of its neural circuit is unknown. Therefore, the aim of this study is to explore the main neural circuit mechanism regulating visceral pain induced by pancreatic cancer in mice. Methods: The mouse model of pancreatic cancer visceral pain was established on C57BL/6N mice by pancreatic injection of mPAKPC-luc cells. Abdominal mechanical hyperalgesia and hunch score were performed to assess visceral pain; the pseudorabies virus (PRV) was used to identify the brain regions innervating the pancreas; the c-fos co-labeling method was used to ascertain the types of activated neurons; in vitro electrophysiological patch-clamp technique was used to record the electrophysiological activity of specific neurons; the calcium imaging technique was used to determine the calcium activity of specific neurons; specific neuron destruction and chemogenetics methods were used to explore whether specific neurons were involved in visceral pain induced by pancreatic cancer. Results: The PRV injected into the pancreas was detected in the paraventricular nucleus of the hypothalamus (PVN). Immunofluorescence staining showed that the majority of c-fos were co-labeled with glutamatergic neurons in the PVN. In vitro electrophysiological results showed that the firing frequency of glutamatergic neurons in the PVN was increased. The calcium imaging results showed that the calcium activity of glutamatergic neurons in the PVN was enhanced. Both specific destruction of glutamatergic neurons and chemogenetics inhibition of glutamatergic neurons in the PVN alleviated visceral pain induced by pancreatic cancer. Conclusions: Glutamatergic neurons in the PVN participate in the regulation of visceral pain induced by pancreatic cancer in mice, providing new insights for the discovery of effective targets for the treatment of pancreatic cancer visceral pain.

19.
Biosens Bioelectron ; 248: 115998, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38176254

RESUMEN

The release of isoprene by plants is considered to be an adaptation to the environment. Herein, a highly selective coumarin fluorescent probe (DMIC) was designed for detecting isoprene. When isoprene came into contact with the maleimide of DMIC, an electrophilic addition process took place. The powerful push-pull effect of DMIC was disrupted. Simultaneously, intramolecular charge transfer was initiated. This enabled DMIC to achieve rapid detection of isoprene within 5 min. Furthermore, excellent linearity was observed in the concentration range of 1-560 ppm (R2 = 0.996). A limit of detection is 1.6 ppm. DMIC was applied to in vitro studies of plant release of liberated isoprene. By monitoring the release of isoprene from different tree species throughout the day, the dynamics of isoprene release from plants throughout the day have been successfully revealed. In addition, the release of isoprene varied considerably among different tree species. In particular, the biocompatibility of DMIC allowed for the in vivo detection of isoprene using fluorescence imaging. The results successfully revealed the dynamics of isoprene release in plants under stress. The amount of isoprene that a plant produced increased with the severity of the stress it experienced. This suggested that the level of isoprene content in plants could be used as a preliminary indicator of the physiological health status of plants. This research demonstrates great potential for clarifying signal transduction in biological systems. It provided ideas for further understanding the biology of isoprene.


Asunto(s)
Técnicas Biosensibles , Butadienos , Plantas , Hemiterpenos , Cumarinas
20.
Adv Sci (Weinh) ; 11(26): e2402756, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38696647

RESUMEN

Colloidal quantum dots (CQDs) are promising optoelectronic materials for solution-processed thin film optoelectronic devices. However, the large surface area with abundant surface defects of CQDs and trap-assisted non-radiative recombination losses at the interface between CQDs and charge-transport layer limit their optoelectronic performance. To address this issue, an interface heterojunction strategy is proposed to protect the CQDs interface by incorporating a thin layer of polyethyleneimine (PEIE) to suppress trap-assisted non-radiative recombination losses. This thin layer not only acts as a protective barrier but also modulates carrier recombination and extraction dynamics by forming heterojunctions at the buried interface between CQDs and charge-transport layer, thereby enhancing the interface charge extraction efficiency. This enhancement is demonstrated by the shortened lifetime of carrier extraction from 0.72 to 0.46 ps. As a result, the resultant PbS CQD solar cells achieve a power-conversion-efficiency (PCE) of 13.4% compared to 12.2% without the heterojunction.

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