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1.
Digit Health ; 10: 20552076241277171, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224794

RESUMEN

Objective: The COVID-19 pandemic has spurred an increased interest in online healthcare and a surge in usage of online healthcare platforms, leading to a proliferation of user-generated online physician reviews. Yet, distinguishing between genuine and fake reviews poses a significant challenge. This study aims to address the challenges delineated above by developing a reliable and effective fake review detection model leveraging deep learning approaches based on a fake review dataset tailored to the context of Chinese online medical platforms. Methods: Inspired by prior research, this paper adopts a crowdsourcing approach to assemble the fake review dataset for Chinese online medical platforms. To develop the fake review detection models, classical machine learning models, along with deep learning models such as Convolutional Neural Network and Bidirectional Encoder Representations from Transformers, were applied. Results: Our experimental deep learning model exhibited superior performance in identifying fake reviews on online medical platforms, achieving a precision of 98.36% and an F2-Score of 97.97%. Compared to the traditional machine learning models (i.e., logistic regression, support vector machine, random forest, ridge regression), this represents an 8.16% enhancement in precision and a 7.7% increase in F2-Score. Conclusion: Overall, this study provides a valuable contribution toward the development of an effective fake physician review detection model for online medical platforms.

2.
Small ; : e2405224, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39246218

RESUMEN

A multimodal sensor array, combining pressure and proximity sensing, has attracted considerable interest due to its importance in ubiquitous monitoring of cardiopulmonary health- and sleep-related biometrics. However, the sensitivity and dynamic range of prevalent sensors are often insufficient to detect subtle body signals. This study introduces a novel capacitive nanocomposite proximity-pressure sensor (NPPS) for detecting multiple human biometrics. NPPS consists of a carbon nanotube-paper composite (CPC) electrode and a percolating multiwalled carbon nanotube (MWCNT) foam enclosed in a MWCNT-coated auxetic frame. The fractured fibers in the CPC electrode intensify an electric field, enabling highly sensitive detection of proximity and pressure. When pressure is applied to the sensor, the synergic effect of MWCNT foam and auxetic deformation amplifies the sensitivity. The simple and mass-producible fabrication protocol allows for building an array of highly sensitive sensors to monitor human presence, sleep posture, and vital signs, including ballistocardiography (BCG). With the aid of a machine learning algorithm, the sensor array accurately detects blood pressure (BP) without intervention. This advancement holds promise for unrestricted vital sign monitoring during sleep or driving.

3.
Talanta ; 281: 126883, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39288585

RESUMEN

A novel smartphone-assisted fluorescent microfluidic-chip was designed for detecting sweat glucose. The microfluidic chip contained six microchambers, each of which was equipped with a glucose sensing membrane incorporating glucose oxidase (GOD), fluorescent O2 probe PtTFPP and H2O2 probe G1. Based upon O2 consumption and H2O2 generation during glucose catalysis by GOD, the chip produced two fluorescence signals towards glucose under single-wavelength excitation, i.e. green fluorescence in response to H2O2 and red fluorescence to O2. The limit of detection (LOD) based on H2O2 monitoring was 0.005 mM, while the LOD based on O2 monitoring was 0.04 mM. Furthermore, the obtained chip was integrated with a smartphone-based portable platform to record RGB values for point-of-care testing of sweat glucose. Glucose calibration (Y = -3.45 + 1.81∗R + 0.68∗G) at 6-min time point was performed by combining R and G channels signals. The dual-monitoring analysis provided a more accurate and reliable verification of glucose detection. This smartphone-assistant optical microfluidic-chip device holds significant potential for portable self-management of glucose in personalized healthcare and clinical diagnosis.

4.
Nat Nanotechnol ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164411

RESUMEN

Microstrain and the associated surface-to-bulk propagation of structural defects are known to be major roadblocks to developing high-energy and long-life batteries. However, the origin and effects of microstrain during the synthesis of battery materials remain largely unknown. Here we perform microstrain screening during real-time and realistic synthesis of sodium layered oxide cathodes. Evidence gathered from multiscale in situ synchrotron X-ray diffraction and microscopy characterization collectively reveals that the spatial distribution of transition metals within individual precursor particles strongly governs the nanoscale phase transformation, local charge heterogeneity and accumulation of microstrain during synthesis. This unexpected dominance of transition metals results in a counterintuitive outward propagation of defect nucleation and growth. These insights direct a more rational synthesis route to reduce the microstrain and crystallographic defects within the bulk lattice, leading to significantly improved structural stability. The present work on microstrain screening represents a critical step towards synthesis-by-design of defect-less battery materials.

5.
Sens Actuators A Phys ; 3772024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39129941

RESUMEN

Capacitors are essential components in modern electrical systems, functioning primarily to store electrical charges and regulate current flow. Capacitive sensors, developed in the 20th century, have become crucial in various applications, including touchscreens and smart devices, due to their ability to detect both metallic and non-metallic objects with high sensitivity and low energy consumption. The advancement of microelectromechanical systems (MEMS) and nanotechnology has significantly enhanced the capabilities of capacitive sensors, leading to unprecedented sensitivity, dynamic range, and cost-effectiveness. These sensors are integral to modern devices, enabling precise measurements of proximity, pressure, strain, and other parameters. This review provides a comprehensive overview of the development, fabrication, and integration of micro and nanostructured capacitive sensors. In terms of an electric field, the working and detection principles are discussed with analytical equations and our numerical results. The focus extends to novel fabrication methods using advanced materials to enhance sensitivities for various parameters, such as proximity, force, pressure, strain, temperature, humidity, and liquid sensing. Their applications are demonstrated in wearable devices, human-machine interfaces, biomedical sensing, health monitoring, robotics control, industrial monitoring, and molecular detection. By consolidating existing research, this review offers insights into the advancements and future directions of capacitive sensor technology.

6.
Chem Sci ; 15(30): 11837-11846, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39092101

RESUMEN

Excellent ethylene selectivity in acetylene semi-hydrogenation is often obtained at the expense of activity. To break the activity-selectivity trade-off, precise control and in-depth understanding of the three-dimensional atomic structure of surfacial active sites are crucial. Here, we designed a novel Au@PdCu core-shell nanocatalyst featuring diluted and stretched Pd sites on the ultrathin shell (1.6 nm), which showed excellent reactivity and selectivity, with 100% acetylene conversion and 92.4% ethylene selectivity at 122 °C, and the corresponding activity was 3.3 times higher than that of the PdCu alloy. The atomic three-dimensional decoding for the activity-selectivity balance was revealed by combining pair distribution function (PDF) and reverse Monte Carlo simulation (RMC). The results demonstrate that a large number of active sites with a low coordination number of Pd-Pd pairs and an average 3.25% tensile strain are distributed on the surface of the nanocatalyst, which perform a pivotal function in the simultaneous improvement of hydrogenation activity and ethylene selectivity. Our work not only develops a novel strategy for unlocking the linear scaling relation in heterogeneous catalysis but also provides a paradigm for atomic 3D understanding of lattice strain in core-shell nanocatalysts.

7.
J Neurosci Methods ; 410: 110249, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39151657

RESUMEN

BACKGROUND: Accurate real-time eye tracking is crucial in oculomotor system research. While the scleral search coil system is the gold standard, its implantation procedure and bulkiness pose challenges. Camera-based systems are affected by ambient lighting and require high computational and electric power. NEW METHOD: This study presents a novel eye tracker using proximity capacitive sensors made of carbon-nanotube-paper-composite (CPC). These sensors detect femtofarad-level capacitance changes caused by primate corneal movement during horizontal and vertical eye rotations. Data processing and machine learning algorithms are evaluated to enhance the accuracy of gaze angle prediction. RESULTS: The system performance is benchmarked against the scleral coil during smooth pursuits, saccades tracking, and fixations. The eye tracker demonstrates up to 0.97 correlation with the coil in eye tracking and is capable of estimating gaze angle with a median absolute error as low as 0.30°. COMPARISON: The capacitive eye tracker demonstrates good consistency and accuracy in comparison to the gold-standard scleral search coil method. CONCLUSIONS: This lightweight, non-invasive capacitive eye tracker offers potential as an alternative to traditional coil and camera-based systems in oculomotor research and vision science.


Asunto(s)
Tecnología de Seguimiento Ocular , Aprendizaje Automático , Nanotubos de Carbono , Animales , Tecnología de Seguimiento Ocular/instrumentación , Movimientos Oculares/fisiología , Macaca mulatta , Masculino , Algoritmos
8.
Biomed Chromatogr ; 38(9): e5948, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38981997

RESUMEN

Epimedium is a traditional Chinese medicine with a wide range of clinical applications; however, there have been numerous reports of adverse reactions in recent years. The most common side effect of Epimedium is liver injury. In this study, the liquid chromatography-mass spectrometry (LC-MS) method has been established to study the components of Epimedium and to identify the components absorbed into the blood of rats. Bioinformatics was used to screen out potential toxic components, and the integrating metabolomics method was used to explore the molecular mechanism of Epimedium-induced liver injury. The chemical constituents of Epimedium were identified by LC-MS, and 62 compounds were obtained, including 57 flavonoids, four organic acids and one alkaloid. The toxicity network of "Epimedium-component-target-liver injury" was constructed using bioinformatics research methods, and then the key hepatotoxic component icaritin was identified. Integrating metabolomics was used to investigate the changes in the metabolic profile of L-02 cells with different durations of icaritin administration compared with the control group, and 106 different metabolites were obtained. A total of 14 potential biomarkers significantly associated with cell survival were screened by Pearson correlation analysis combined with the L-02 cell survival rate. Our study preliminarily revealed the mechanism of hepatotoxicity induced by Epimedium.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Biología Computacional , Epimedium , Flavonoides , Metabolómica , Ratas Sprague-Dawley , Epimedium/química , Metabolómica/métodos , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Ratas , Flavonoides/química , Flavonoides/farmacología , Masculino , Humanos , Cromatografía Liquida/métodos , Línea Celular , Espectrometría de Masas/métodos , Medicamentos Herbarios Chinos/química , Metaboloma/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos
10.
J Am Chem Soc ; 146(28): 19042-19049, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38950194

RESUMEN

A bimetallic, two-coordinated carbene-metal-amine (cMa) Au(I) complex featuring a twisted tandem carbene structure (NHC1-Au-NHC2-Au-carbazolyl) was synthesized. The molecular structure in single crystals revealed a large dihedral angle between the two carbene ligands, while the bridged carbene NHC2 and carbazolyl (Cz) ligands were coplanar. A bluish green thermally stimulated delayed phosphorescence (TSDP) was observed in crystals with an emission lifetime over 70 µs, which can be attributed to the spin allowed diabatic population of a high-lying emissive triplet state from the 3LE characterized low-lying ones. The small rotation energy barrier of Cz along the coordination bond allowed conformers with large dihedral angles between NHC2 and Cz. The ICT characterized S1 state was consequently stabilized to achieve a thermally accessible energy gap to facilitate ISC between triplets and the S1, leading to the thermally activated delayed fluorescence (TADF). Simultaneous TSDP and TADF dual emission can be recorded in its doped polymer film owing to the coexistence of these different conformers.

11.
Proc Natl Acad Sci U S A ; 121(26): e2319811121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38889146

RESUMEN

Rational design of plant cis-regulatory DNA sequences without expert intervention or prior domain knowledge is still a daunting task. Here, we developed PhytoExpr, a deep learning framework capable of predicting both mRNA abundance and plant species using the proximal regulatory sequence as the sole input. PhytoExpr was trained over 17 species representative of major clades of the plant kingdom to enhance its generalizability. Via input perturbation, quantitative functional annotation of the input sequence was achieved at single-nucleotide resolution, revealing an abundance of predicted high-impact nucleotides in conserved noncoding sequences and transcription factor binding sites. Evaluation of maize HapMap3 single-nucleotide polymorphisms (SNPs) by PhytoExpr demonstrates an enrichment of predicted high-impact SNPs in cis-eQTL. Additionally, we provided two algorithms that harnessed the power of PhytoExpr in designing functional cis-regulatory variants, and de novo creation of species-specific cis-regulatory sequences through in silico evolution of random DNA sequences. Our model represents a general and robust approach for functional variant discovery in population genetics and rational design of regulatory sequences for genome editing and synthetic biology.


Asunto(s)
Polimorfismo de Nucleótido Simple , Secuencias Reguladoras de Ácidos Nucleicos , Zea mays , Secuencias Reguladoras de Ácidos Nucleicos/genética , Zea mays/genética , Sitios de Carácter Cuantitativo , Algoritmos , Regulación de la Expresión Génica de las Plantas , Aprendizaje Profundo , Plantas/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Modelos Genéticos , Genes de Plantas , Sitios de Unión/genética
12.
Opt Lett ; 49(11): 3018-3021, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824317

RESUMEN

We demonstrate a monolithic tunable dual-wavelength laser fabricated on erbium-doped lithium niobate on an insulator (Er:LNOI). The dual-wavelength laser enables independent tuning with a continuously linear electro-optic (EO)-modulated tuning range of 11.875 GHz at a tuning efficiency of 0.63 pm/V. Tunable microwave generation within 50 GHz with a maximum extinction ratio of 35 dB is experimentally demonstrated by further exploring the charge accumulation effect in LNOI. The monolithic design of this work paves the way for microscale integration of laser devices, presenting significant prospects in photonics research and applications.

13.
Front Neurol ; 15: 1378689, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38841698

RESUMEN

Objective: To visualize and analyze the literature related to sciatic nerve injury treatment from January 2019 to December 2023, and summarize the current status, hotspots, and development trends of research in this field. Methods: Using CiteSpace and VOSviewer software, we searched the Web of Science database for literature related to the treatment of sciatic nerve injury. Then we analyzed and plotted visualization maps to show the number of publications, countries, institutions, authors, keywords, references, and journals. Results: A total of 2,653 articles were included in the English database. The annual number of publications exceeded 230, and the citation frequency increased yearly. The United States and China were identified as high-influence nations in this field. Nantong University was the leading institution in terms of close cooperation among institutions. The authors Wang Yu had the highest number of publications and were highly influential in this field. Keyword analysis and reference Burst revealed a research focus on nerve regeneration and neuropathic pain, which involve regenerative medicine and neural tissue engineering. Chronic pain resulting from sciatic nerve injury often manifests alongside anxiety, depression, cognitive-behavioral disorders, and other issues. Interventions such as stem cells, electrical stimulation, electroacupuncture, total joint replacement, pharmacological interventions, gene therapy, nerve conduits, chitosan scaffolds, and exercise promote nerve repair and alleviate pain. Schwann cells have been the focus of much attention in nerve repair and regeneration. Improving the outcome of sciatic nerve injury is a current research challenge and focus in this field. Based on keyword Burst, nerve conduits and grafts may become a potential research hotspot in the treatment of sciatic nerve injury. Conclusion: This visual analysis summarizes research trends and developments of sciatic nerve injury treatment and predicts potential research frontiers and hot directions.

14.
J Am Chem Soc ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847794

RESUMEN

Traditional Li-ion intercalation chemistry into graphite anodes exclusively utilizes the cointercalation-free or cointercalation mechanism. The latter mechanism is based on ternary graphite intercalation compounds (t-GICs), where glyme solvents were explored and proved to deliver unsatisfactory cyclability in LIBs. Herein, we report a novel intercalation mechanism, that is, in situ synthesis of t-GIC in the tetrahydrofuran (THF) electrolyte via a spontaneous, controllable reaction between binary-GIC (b-GIC) and free THF molecules during initial graphite lithiation. The spontaneous transformation from b-GIC to t-GIC, which is different from conventional cointercalation chemistry, is characterized and quantified via operando synchrotron X-ray and electrochemical analyses. The resulting t-GIC chemistry obviates the necessity for complete Li-ion desolvation, facilitating rapid kinetics and synchronous charge/discharge of graphite particles, even under high current densities. Consequently, the graphite anode demonstrates unprecedented fast charging (1 min), dendrite-free low-temperature performance, and ultralong lifetimes exceeding 10 000 cycles. Full cells coupled with a layered cathode display remarkable cycling stability upon a 15 min charging and excellent rate capability even at -40 °C. Furthermore, our chemical strategies are shown to extend beyond Li-ion batteries to encompass Na-ion and K-ion batteries, underscoring their broad applicability. Our work contributes to the advancement of graphite intercalation chemistry and presents a low-cost, adaptable approach for achieving fast-charging and low-temperature batteries.

15.
Oncologist ; 29(9): e1104-e1112, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-38780143

RESUMEN

BACKGROUND: Patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2 negative (HER2-) early breast cancer (EBC) with high-risk clinicopathological features face an increased risk of recurrence. This study explored the evolving treatment landscape and clinical outcomes in patients with EBC using a nationwide database. PATIENTS AND METHODS: The study cohort comprised HR+/HER2-, stages 1-3, patients with EBC who underwent surgery and received adjuvant endocrine therapy (AET) from January 2013 to March 2021. High-risk patients were defined by ≥4 positive axillary lymph nodes, or 1-3 positive lymph node(s) with at least one high-risk feature (histologic grade 3, tumor size ≥5 cm, or Ki-67 ≥20%). A low-risk cohort included patients not meeting the criteria. Survival analysis was conducted with a cutoff of September 2021. RESULTS: The study included 4088 eligible patients (1310 high-risk patients and 2778 low-risk patients). High-risk patients were more likely to receive adjuvant chemotherapy and radiotherapy compared to low-risk patients. From 2013 to 2021, an increasing proportion of patients received aromatase inhibitors and ovarian function suppression as part of their AET. The 2-, 5-, and 7-year invasive disease-free survival for high-risk cohort were 90.67%, 75.26%, and 57.10%, respectively, these rates were notably higher for low-risk cohort at 97.14%, 89.85%, and 84.83%. High-risk patients demonstrated a higher risk of recurrence or death compared with low-risk patients (hazard ratio, 2.38; 95% CI, 1.82-3.12). CONCLUSION: In the setting of standard or even intensive AET, patients with EBC with high-risk features still present high recurrence risk, highlighting the urgent need for innovative adjuvant treatment strategies.


Asunto(s)
Neoplasias de la Mama , Receptor ErbB-2 , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/tratamiento farmacológico , Receptor ErbB-2/metabolismo , Persona de Mediana Edad , China/epidemiología , Quimioterapia Adyuvante/métodos , Adulto , Anciano , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/tratamiento farmacológico
16.
Bone ; 185: 117132, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38789096

RESUMEN

The mechanosensitivity of inflammation can alter cellular mechanotransduction. However, the underlying mechanism remains unclear. This study aims to investigate the metabolic mechanism of inflammation under mechanical force to guide tissue remodeling better. Herein, we found that inflammation hindered bone remodeling under mechanical force, accompanied by a simultaneous enhancement of oxidative phosphorylation (OXPHOS) and glycolysis. The control of metabolism direction through GNE-140 and Visomitin revealed that enhanced glycolysis might act as a compensatory mechanism to resist OXPHOS-induced osteoclastogenesis by promoting osteogenesis. The inhibited osteogenesis induced by inflammatory mechanical stimuli was concomitant with a reduced expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). PGC-1α knockdown impeded osteogenesis under mechanical force and facilitated osteoclastogenesis by enhancing OXPHOS. Conversely, PGC-1α overexpression attenuated the impairment of bone remodeling by inflammatory mechanical signals through promoting glycolysis. This process benefited from the PGC-1α regulation on the transcriptional and translational activity of lactate dehydrogenase A (LDHA) and the tight control of the extracellular acidic environment. Additionally, the increased binding between PGC-1α and LDHA proteins might contribute to the glycolysis promotion within the inflammatory mechanical environment. Notably, LDHA suppression effectively eliminated the bone repair effect mediated by PGC-1α overexpression within inflammatory mechanical environments. In conclusion, this study demonstrated a novel molecular mechanism illustrating how inflammation orchestrated glucose metabolism through glycolysis and OXPHOS to affect mechanically induced bone remodeling.


Asunto(s)
Remodelación Ósea , Glucólisis , Inflamación , Osteogénesis , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Transducción de Señal , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Animales , Remodelación Ósea/fisiología , Inflamación/metabolismo , Inflamación/patología , Osteogénesis/fisiología , Ratones , Ratones Endogámicos C57BL , L-Lactato Deshidrogenasa/metabolismo , Fosforilación Oxidativa , Microambiente Celular , Masculino
17.
Bioresour Technol ; 403: 130891, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38788808

RESUMEN

To reduce the cost of docosahexaenoic acid (DHA) production from Schizochytrium sp., the waste Pichia pastoris was successfully used as an alternative nitrogen source to achieve high-density cultivation during the cell growth phase. However, due to the high oxygen consumption feature when implementing high-density cultivation, the control of both the nitrogen source and dissolved oxygen concentration (DO) at each sufficient level was impossible; thus, two realistic control strategies, including "DO sufficiency-nitrogen limitation" and "DO limitation-nitrogen sufficiency", were proposed. When using the strategy of "DO sufficiency-nitrogen limitation", the lowest maintenance coefficient of glucose (12.3 mg/g/h vs. 17.0 mg/g/h) and the highest activities of related enzymes in DHA biosynthetic routes were simultaneously obtained; thus, a maximum DHA concentration of 12.8 ± 1.2 g/L was achieved, which was 1.58-fold greater than that of the control group. Overall, two-stage feeding control for alternative nitrogen sources is an efficient strategy to industrial DHA fermentation.


Asunto(s)
Ácidos Docosahexaenoicos , Nitrógeno , Estramenopilos , Ácidos Docosahexaenoicos/metabolismo , Ácidos Docosahexaenoicos/biosíntesis , Nitrógeno/metabolismo , Estramenopilos/metabolismo , Fermentación , Oxígeno/metabolismo , Glucosa/metabolismo , Saccharomycetales/metabolismo
18.
Nano Lett ; 24(21): 6269-6277, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38743874

RESUMEN

Accurately decoding the three-dimensional atomic structure of surface active sites is essential yet challenging for a rational catalyst design. Here, we used comprehensive techniques combining the pair distribution function and reverse Monte Carlo simulation to reveal the surficial distribution of Pd active sites and adjacent coordination environment in palladium-copper nanoalloys. After the fine-tuning of the atomic arrangement, excellent catalytic performance with 98% ethylene selectivity at complete acetylene conversion was obtained in the Pd34Cu66 nanocatalysts, outperforming most of the reported advanced catalysts. The quantitative deciphering shows a large number of active sites with a Pd-Pd coordination number of 3 distributed on the surface of Pd34Cu66 nanoalloys, which play a decisive role in highly efficient semihydrogenation. This finding not only opens the way for guiding the precise design of bimetal nanocatalysts from atomic-level insight but also provides a method to resolve the spatial structure of active sites.

19.
Science ; 384(6698): 912-919, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38781394

RESUMEN

Transitioning from polycrystalline to single-crystalline nickel-rich cathodes has garnered considerable attention in both academia and industry, driven by advantages of high tap density and enhanced mechanical properties. However, cathodes with high nickel content (>70%) suffer from substantial capacity degradation, which poses a challenge to their commercial viability. Leveraging multiscale spatial resolution diffraction and imaging techniques, we observe that lattice rotations occur universally in single-crystalline cathodes and play a pivotal role in the structure degradation. These lattice rotations prove unrecoverable and govern the accumulation of adverse lattice distortions over repeated cycles, contributing to structural and mechanical degradation and fast capacity fade. These findings bridge the previous knowledge gap that exists in the mechanistic link between fast performance failure and atomic-scale structure degradation.

20.
Environ Int ; 187: 108710, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38701644

RESUMEN

Exposure to persistent organic pollutants (POPs), such as dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs), has historically been linked to population collapses in wildlife. Despite international regulations, these legacy chemicals are still currently detected in women of reproductive age, and their levels correlate with reduced ovarian reserve, longer time-to-pregnancy, and higher risk of infertility. However, the specific modes of action underlying these associations remain unclear. Here, we examined the effects of five commonly occurring POPs - hexachlorobenzene (HCB), p,p'-dichlorodiphenyldichloroethylene (DDE), 2,3,3',4,4',5-hexachlorobiphenyl (PCB156), 2,2',3,4,4',5,5'-heptachlorobiphenyl (PCB180), perfluorooctane sulfonate (PFOS) - and their mixture on human ovaries in vitro. We exposed human ovarian cancer cell lines COV434, KGN, and PA1 as well as primary ovarian cells for 24 h, and ovarian tissue containing unilaminar follicles for 6 days. RNA-sequencing of samples exposed to concentrations covering epidemiologically relevant levels revealed significant gene expression changes related to central energy metabolism in the exposed cells, indicating glycolysis, oxidative phosphorylation, fatty acid metabolism, and reactive oxygen species as potential shared targets of POP exposures in ovarian cells. Alpha-enolase (ENO1), lactate dehydrogenase A (LDHA), cytochrome C oxidase subunit 4I1 (COX4I1), ATP synthase F1 subunit alpha (ATP5A), and glutathione peroxidase 4 (GPX4) were validated as targets through qPCR in additional cell culture experiments in KGN. In ovarian tissue cultures, we observed significant effects of exposure on follicle growth and atresia as well as protein expression. All POP exposures, except PCB180, decreased unilaminar follicle proportion and increased follicle atresia. Immunostaining confirmed altered expression of LDHA, ATP5A, and GPX4 in the exposed tissues. Moreover, POP exposures modified ATP production in KGN and tissue culture. In conclusion, our results demonstrate the disruption of cellular energy metabolism as a novel mode of action underlying POP-mediated interference of follicle growth in human ovaries.


Asunto(s)
Metabolismo Energético , Fluorocarburos , Ovario , Contaminantes Orgánicos Persistentes , Humanos , Femenino , Ovario/efectos de los fármacos , Ovario/metabolismo , Metabolismo Energético/efectos de los fármacos , Fluorocarburos/toxicidad , Homeostasis/efectos de los fármacos , Línea Celular Tumoral , Bifenilos Policlorados/toxicidad , Diclorodifenil Dicloroetileno/toxicidad , Ácidos Alcanesulfónicos/toxicidad , Hexaclorobenceno/toxicidad
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