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1.
Phys Chem Chem Phys ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140173

RESUMEN

Acetylcholine (Ach) is a common neurotransmitter in the central nervous system (CNS) and peripheral nervous system (PNS). It is one of the neurotransmitters in the autonomic nervous system and the main neurotransmitter in all autonomic ganglia. Experiments have confirmed that electromagnetic waves can affect the synthesis of animal neurotransmitters, but the microscopic effects of electromagnetic waves in the terahertz (THz) frequency band are still unclear. Based on density functional theory (DFT) and molecular dynamics (MD) simulation methods, this paper studies the effect of THz electromagnetic waves on the binding of choline to choline acetyltransferase (ChAT). By emitting THz waves that resonate with the characteristic vibration mode of choline near the active site, it was found that THz waves with a frequency of 45.3 THz affected the binding of choline to ChAT, especially the binding of the active site histidine His324 to choline. The main evidence is that under the action of THz waves, the binding free energy of choline to histidine His324 and ChAT at the active site was significantly reduced compared to noE, which may have a potential impact on the enzymatic synthesis of Ach. It is expected to achieve the purpose of regulating the synthesis of the neurotransmitter Ach under the action of THz waves and treat certain nervous system diseases.

2.
Front Endocrinol (Lausanne) ; 15: 1429154, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39119007

RESUMEN

Purpose: The study aimed to investigate the correlation between the change of sex hormone levels and ocular surface parameters in girls with idiopathic central precocious puberty(ICPP). Methods: Eighteen girls with ICPP and 18 age-matched normal girls participated in this study, all of the participants had undergone physical measurements, laboratory tests, imaging examination and ocular surface assessments. Results: The Objective Scatter Index (OSI) in the ICPP group was significantly higher than in the control group (P = 0.031), girls with ICPP showed slightly lower MNITBUT compared to the normal control group, although this difference was not statistically significant. Bivariate analysis revealed a positive association between estradiol and OSI (r=0.383, P=0.021), Additionally, in the study population, both Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH) were negatively correlated with Mean noninvasive tear breakup time (MNITBUT) (r=-0.359, P=0.031)(r=-0.357, P=0.032). Conclusion: In comparison with the normal control group, alterations in the OSI were observed in girls with ICPP. This alteration may be associated with an elevation in estrogen levels. Although there was a slight non-significant decrease in NITBUT in ICPP girls, the negative correlation between LH and FSH with MNITBUT suggests new perspective for further investigation.


Asunto(s)
Hormona Folículo Estimulante , Hormona Luteinizante , Pubertad Precoz , Lágrimas , Humanos , Femenino , Pubertad Precoz/sangre , Pubertad Precoz/metabolismo , Niño , Hormona Luteinizante/sangre , Lágrimas/metabolismo , Hormona Folículo Estimulante/sangre , Estradiol/sangre , Hormonas Esteroides Gonadales/sangre , Estudios de Casos y Controles
3.
Adv Sci (Weinh) ; : e2405137, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136047

RESUMEN

It is still a challenge to construct single-atom level reduction and oxidation sites in single-component photocatalyst by manipulating coordination configuration for photocatalytic water splitting. Herein, the atomically dispersed asymmetric configuration of six-coordinated Co-S2O4 (two exposed S atoms, two OH groups, and two Co─O─Zn bonds) suspending on ZnIn2S4 nanosheets verified by combining experimental analysis with theoretical calculation, is applied into photocatalytic water splitting. The Co-S2O4 site immobilized by Vs acts as oxidation sites to guide electrons transferring to neighboring independent S atom, achieving efficient separation of reduction and oxidation sites. It is worth mentioning that stabilized Co-S2O4 configuration show dynamic structure evolution to highly active Co-S1O4 configuration (one exposed S atom, one OH group, and three Co─O─Zn bonds) in reaction, which lowers energy barrier of transition state for H2O activization. Ultimately, the optimized photocatalyst exhibits excellent photocatalytic activity for water splitting (H2: 80.13 µmol g-1 h-1, O2: 37.81 µmol g-1 h-1) and outstanding stability than that of multicomponent photocatalysts due to dynamic and reversible evolution between stable Co-S2O4 configuration and active Co-S1O4 configuration. This work demonstrates new cognitions on immobilized strategy through vacancy inducing, manipulating coordination configuration, and dynamic evolution mechanism of single-atom level catalytic site in photocatalytic water splitting.

4.
Front Psychol ; 15: 1455499, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39176046
5.
ACS Appl Mater Interfaces ; 16(28): 37087-37099, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38958653

RESUMEN

Hydrogels, as flexible materials, have been widely used in the field of flexible sensors. Human sweat contains a variety of biomarkers that can reflect the physiological state of the human body. Therefore, it is of great practical significance and application value to realize the detection of sweat composition and combine it with human motion sensing through a hydrogel. Based on mussel-inspired chemistry, polydopamine (PDA) and gold nanoparticles (AuNPs) were coated on the surface of cellulose nanocrystals (CNCs) to obtain CNC-based nanocomposites (CNCs@PDA-Au), which could simultaneously enhance the mechanical, electrochemical, and self-healing properties of hydrogels. The CNCs@PDA-Au was composited with poly(vinyl alcohol) (PVA) hydrogel to obtain the nanocomposite hydrogel (PVA/CNCs@PDA-Au) by freeze-thaw cycles. The PVA/CNCs@PDA-Au has excellent mechanical strength (7.2 MPa) and self-healing properties (88.3%). The motion sensors designed with PVA/CNCs@PDA-Au exhibited a fast response time (122.9 ms), wide strain sensing range (0-600.0%), excellent stability, and fatigue resistance. With the unique electrochemical redox properties of uric acid, the designed hydrogel sensor successfully realized the detection of uric acid in sweat with a wide detection range (1.0-100.0 µmol/L) and low detection limit (0.42 µmol/L). In this study, the dual detection of human motion and uric acid in sweat was successfully realized by the designed PVA/CNCs@PDA-Au nanocomposite hydrogel.


Asunto(s)
Celulosa , Oro , Hidrogeles , Nanocompuestos , Polímeros , Sudor , Celulosa/química , Nanocompuestos/química , Humanos , Hidrogeles/química , Oro/química , Sudor/química , Polímeros/química , Nanopartículas del Metal/química , Alcohol Polivinílico/química , Nanopartículas/química , Indoles/química , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Límite de Detección , Movimiento (Física)
6.
Langmuir ; 40(28): 14602-14612, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38963442

RESUMEN

Cellulose nanocrystals (CNCs) have garnered significant attention as a modifiable substrate because of their exceptional performances, including remarkable degradability, high tensile strength, high elastic modulus, and biocompatibility. In this article, the successful adsorption of phytic acid (PA) onto the surface of cellulose nanocrystals @polydopamine (CNC@PDA) was achieved. Taking inspiration from mussels, a dopamine self-polymerization reaction was employed to coat the surface of CNCs with PDA. Utilizing Pickering emulsion, the CNC@PDA-PA nanomaterial was obtained by grafting PA onto CNC@PDA. An environmentally friendly hydrogel was prepared through various reversible interactions using poly(acrylic acid) (PAA) and Fe3+ as raw materials with the assistance of CNC@PDA-PA. By multiple hydrogen bonding and metal-ligand coordination, nanocomposite hydrogels exhibit remarkable mechanical properties (the tensile strength and strain were 1.82 MPa and 442.1%, respectively) in addition to spectacular healing abilities (96.6% after 5 h). The study aimed to develop an innovative approach for fabricating nanocomposite hydrogels with exceptional self-healing capabilities.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38884632

RESUMEN

BACKGROUND AND OBJECTIVES: The integration of lean management in optimizing nursing workflow necessitates the careful examination of several factors, including nurses' work efficiency, patient experience, and health outcomes. To evaluate the extent of unfinished nursing care and patient satisfaction, we have incorporated the lean management approach into our quality improvement efforts. This proactive measure aims to address potential adverse outcomes, such as subpar inpatient experiences, escalated occurrence of adverse events, and decreased job satisfaction among nursing staff. METHODS: We utilized the lean management methodology of value stream mapping in a specific facility between February and August 2021, aiming to pinpoint the crucial areas for enhancing nurses' workflow. By employing fishbone diagrams, we thoroughly analyzed the underlying causes, and subsequently employed the Plan-Do-Study-Act model to execute interventions devised based on these identified causes. Interventions included: (1) specifying the time of doctors' conventional rounds; (2) changing unreasonable scheduling; (3) employing 5S management to manage nursing supplies; and (4) eliminating duplicate papers and electronic reports. RESULTS: After implementing these interventions, the rate of unfinished nursing reduced from 73.4% to 39.6%, and that of finished nursing care during the shift increased from 38.6% to 71.4%. Overtime was reduced from 37.2 ± 22.4 minutes to 14.1 ± 3.6 minutes. The total patient satisfaction score for the Patient Satisfaction Questionnaire short-form increased (P < .05). CONCLUSIONS: The lean management of quality improvement methodologies provides effective enhancement to the work efficiency of nurses.

8.
Front Cardiovasc Med ; 11: 1335218, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38932987

RESUMEN

Background: Severe tricuspid regurgitation (TR) causing cyanosis with patent foramen ovale (PFO) and right-to-left atrial shunting requires a precise diagnosis for optimal therapy. Tricuspid valve prolapse (TVP) can lead to TR and is sometimes overlooked, especially in complex cases with factors like pulmonary hypertension (PH). We present an infant with cyanosis and profound TR after high-altitude exposure, initially misattributed to PH but found to be primarily due to spontaneous chordae tendineae rupture and TVP. This case underscores the challenges in diagnosing TR-induced cyanosis. Case presentation: The 3-month-old infant rapidly developed cyanosis, hypoxemia, right atrial enlargement, severe tricuspid regurgitation (TR), and patent foramen ovale (PFO) shunting after high-altitude exposure. Although echocardiography revealed tricuspid valve prolapse (TVP), initial consideration linked TR and right-to-left shunting to pulmonary hypertension (PH) due to the temporal correlation with rapid altitude exposure. Despite hemodynamic stability and the absence of respiratory distress after respiratory support and combined PH medication therapy, the persistent hypoxemia did not reverse as expected. This treatment outcome and repeated echocardiograms reminded us that TR was primarily caused by TVP rather than PH alone. Intraoperative exploration confirmed that TVP was caused by a rupture of TV chordae tendineae and anterior papillary muscle head, and the chordae tendineae/papillary muscle connection was reconstructed. After surgery, this patient was noncyanotic with an excellent long-term prognosis, a trivial TR with normal TV function being observed echocardiographically. Conclusions: TR-induced cyanosis can be not only a consequence of PH and right-sided heart dilation but also a primary condition. Repetitive reassessment should be undertaken with caution, particularly when patients are not improving on therapy in the setting of conditions known to predisposition to secondary TR. Since TVP caused by rupture of the chordae or papillary muscles is rare but fatal in children, early diagnosis is clinically substantial to proper management and satisfactory long-term outcomes.

9.
IEEE Open J Eng Med Biol ; 5: 316-329, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38766542

RESUMEN

Objective: A biological system's internal morphological structure or function can be changed as a result of the mechanical effect of focused ultrasound. Pulsed low-intensity focused ultrasound (LIFU) has mechanical effects that might induce follicle development with less damage to ovarian tissue. The potential development of LIFU as a non-invasive method for the treatment of female infertility is being considered, and this study sought to explore and confirm that LIFU can activate ovarian follicles. Results: We found a 50% increase in ovarian weight and in the number of mature follicles on the ultrasound-stimulated side with pulsed LIFU and intraperitoneal injection of 10 IU PMSG in 10-day-old rats. After ultrasound stimulation, the PCOS-like rats had a decrease in androgen levels, restoration of regular estrous cycle and increase in the number of mature follicles and corpora lutea, and the ratio of M1 and M2 type macrophages was altered in antral follicles of PCOS-like rats, consequently promoting further development and maturation of antral follicles. Conclusion: LIFU treatment could trigger actin changes in ovarian cells, which might disrupt the Hippo signal pathway to promote follicle formation, and the mechanical impact on the ovaries of PCOS-like rats improved antral follicle development.

10.
Bioresour Technol ; 402: 130808, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723724

RESUMEN

The substantial discharge of ferroferric oxide nanoparticles (Fe3O4 NPs) into sewage threatens the survival of functional microorganisms in wastewater treatment. This study elucidated responses of anaerobic ammonium oxidation (anammox) consortia to inhibition from high Fe3O4 NPs concentration and recovery mechanisms. The nitrogen removal efficiency decreased by 20.3 % and recovered after 55 days under 1000 mg/L Fe3O4 NPs concentration. Toxicity was attributed to reactive oxygen species (ROS) production. The excessive ROS damaged membrane integrity, nitrogen metabolism, and DNA synthesis, resulting in the inhibition of anammox bacteria activity. However, recovery mechanisms of anammox consortia activity were activated in response to 1000 mg/L Fe3O4 NPs. The increase of heme oxygenase-1, thioredoxin, and nicotinamide adenine dinucleotide-quinone oxidoreductase genes alleviated oxidative stress. Furthermore, the activation of metabolic processes associated with membrane and DNA repair promoted recovery of anammox bacteria activity. This study provided new insights into NPs contamination and control strategies during anammox process.


Asunto(s)
Oxidación-Reducción , Especies Reactivas de Oxígeno , Especies Reactivas de Oxígeno/metabolismo , Compuestos de Amonio/metabolismo , Anaerobiosis , Nitrógeno , Bacterias/metabolismo , Consorcios Microbianos , Estrés Oxidativo/efectos de los fármacos , Aguas Residuales/química
11.
Technol Health Care ; 32(4): 2251-2264, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38517814

RESUMEN

BACKGROUND: Psychrophilic bacteria can survive in a unique living environment. OBJECTIVE: To explore the mechanism of low temperature adaptation and the physiological function of thermophilic metabolic genes. METHOD: Serratia marcescens strain F13 stored in microbial laboratory was cultured at 5∘C, 10∘C and 25∘C respectively, and the obtained strains were sequenced by high-throughput transcriptome. Serratia marcescens strain CAV1761 was used as the reference strain. The data produced by transcriptome sequencing were statistically analyzed by biostatistics software such as soapnuke, soap and edger. The differentially expressed genes were found based on the gene expression, and analyzed by Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. RESULTS: The results showed that there were 718 differential genes in F13-10 vs F13-5 comparison group, 1614 differential genes in F13-25 vs F13-5 comparison group and 1636 differential genes in F13-25 vs F13-10 comparison group. GO function enrichment analysis showed that the GO term mainly enriched by different genes in the three comparison groups was mostly related to the migration and transport of cellular or subcellular components, cell localization and transmembrane transporter activity, as well as cilia or flagella dependent cell movement. In the enrichment analysis of KEGG pathway, the three comparison groups all enriched the largest number of differential genes in the branch pathway of KEGG metabolism, followed by the branch pathway of environmental information processing. CONCLUSION: In F13-10 vs F13-5, the differential genes were mainly concentrated in 20 pathways such as ATP-binding cassette transport (ABC) transporters, thiamine metabolism and flagella assembly; In F13-25 vs F13-5, the differential genes are mainly concentrated in 20 pathways, such as (ABC) transporters, arginine and proline metabolism, two-component system and so on; In F13-25 vs F13-10, the differential genes are mainly concentrated in 20 pathways such as various types of glycan synthesis, two-component system and arginine metabolism.


Asunto(s)
Serratia marcescens , Transcriptoma , Serratia marcescens/genética , Frío , Perfilación de la Expresión Génica/métodos
12.
Medicine (Baltimore) ; 103(7): e36923, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363945

RESUMEN

RATIONALE: Klippel-Trenaunay syndrome (KTS) is a rare congenital venous malformation, it had been found to be caused by mutations of the phosphatidylinositol 4, 5-diphosphate 3-kinase catalytic subunit alpha (PIK3CA) gene. Currently KTS is defined as a triad of skin wine pigmented spots, varicose veins and malformations of the lower extremities, and hypertrophy of bone and soft tissue, involving urinary system up to 6% to 30%. When the urinary system is involved, KTS is often presented as painless massive gross hematuria. PATIENT CONCERNS: This article describes a woman who was hospitalized with painless massive gross hematuria. Physical examination revealed significant hypertrophy of the right lower limb with varicose veins, port-wine stains in the skin, and right perineal hemangiomatous changes with swelling. The patient was admitted to hospital 4 times for repeated hematuria and infection. DIAGNOSES: By physical examination, CT urography, ureteroscopy and cystoscopy, the patient was diagnosed to have Klippel-Trenaunay syndrome, involving the urinary system. INTERVENTIONS: The patient hematuria improved after multiple indwelling D-J tubes and anti-inflammatory treatment. OUTCOMES: The final symptoms of hematuria improved significantly, follow-up so far has not recurred. LESSONS: This case presents the possibility of painless gross hematuria with KTS. Most of patients can be improved by conservative treatment. Cystoscopic laser therapy is the preferred treatment for poor bleeding control. Cystectomy and nephrectomy should be considered when life-threatening.


Asunto(s)
Síndrome de Klippel-Trenaunay-Weber , Várices , Femenino , Humanos , Síndrome de Klippel-Trenaunay-Weber/complicaciones , Síndrome de Klippel-Trenaunay-Weber/diagnóstico , Hematuria/etiología , Venas/anomalías , Várices/complicaciones , Hipertrofia
13.
Heliyon ; 10(4): e25569, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38384527

RESUMEN

Background: Although dilated cardiomyopathy (DCM) is a prevalent form of cardiomyopathy, the molecular mechanisms underlying its pathogenesis and progression remain poorly understood. It is possible to identify and validate DCM-associated genes, pathways, and miRNAs using bioinformatics analysis coupled with clinical validation methods. Methods: Our analysis was performed using 3 mRNA datasets and 1 miRNA database. We employed several approaches, including gene ontology (GO) analysis, KEGG pathway enrichment analysis, protein-protein interaction networks analysis, and analysis of hub genes to identify critical genes and pathways linked to DCM. We constructed a regulatory network for DCM that involves interactions between miRNAs and mRNAs. We also validated the differently expressed miRNAs in clinical samples (87 DCM ,83 Normal) using qRT-PCR.The miRNAs' clinical value was evaluated by receiver operating characteristic curves (ROCs). Results: 78 differentially expressed genes (DEGs) and 170 differentially expressed miRNAs (DEMs) were associated with DCM. The top five GO annotations were collagen-containing extracellular matrix, cell substrate adhesion, negative regulation of cell differentiation, and inflammatory response. The most enriched KEGG pathways were the Neurotrophin signaling pathway, Thyroid hormone signaling pathway, Wnt signaling pathway, and Axon guidance. In the PPI network, we identified 10 hub genes, and in the miRNA-mRNA regulatory network, we identified 8 hub genes and 15 miRNAs. In the clinical validation, we found 13 miRNAs with an AUC value greater than 0.9. Conclusion: Our research offers novel insights into the underlying mechanisms of DCM and has implications for identifying potential targets for diagnosis and treatment of this condition.

14.
J Pharm Biomed Anal ; 242: 116059, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38422672

RESUMEN

Central precocious puberty (CPP) is a prevalent endocrine disorder that primarily affects children, specifically females, and is associated with various physical and psychological complications. Although Kangzao granules (KZG) are efficacious in managing CPP, the underlying mechanisms remain unclear. Therefore, this study aimed to elucidate the therapeutic mechanisms of KZG using network pharmacology, molecular docking, pharmacodynamics, and pathway validation. A putative compound-target-pathway network was constructed using Cytoscape, before KEGG and Gene Ontology enrichment analyses were conducted. Moreover, molecular docking was performed using AutoDockTools. Quality control of the 10 key components of KZG was carried out using UHPLC-ESI/LTQ-Orbitrap-MS/MS, and hypothalamic lipids were analyzed using UHPLC-Q-Exactive Orbitrap MS/MS. In total, 87 bioactive compounds that targeting 110 core proteins to alleviate CPP were identified in KZG. Lipidomic analysis revealed 18 differential lipids among the CPP, KZG, and control groups, wherein fatty acids were significantly reduced in the model group; however, these changes were effectively counteracted by KZG treatment. Molecular docking analysis revealed a strong binding affinity between flavonoids and RAC-alpha serine/threonine-protein kinase (AKT) when docked into the crystal structure. Moreover, a substantial disruption in lipid metabolism was observed in the model group; however, treatment with KZG efficiently reversed these alterations. Furthermore, the phosphoinositide 3-kinase/AKT signaling pathway was identified as a pivotal regulator of hypothalamic lipid metabolism regulator. Overall, this study highlights the effectiveness of a multidisciplinary approach that combines network pharmacology, lipidomics, molecular docking, and experimental validation in the elucidation of the therapeutic mechanisms of KZG in CPP treatment.


Asunto(s)
Medicamentos Herbarios Chinos , Pubertad Precoz , Humanos , Niño , Femenino , Animales , Ratas , Farmacología en Red , Lipidómica , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Pubertad Precoz/tratamiento farmacológico , Espectrometría de Masas en Tándem , Ácidos Grasos , Hipotálamo , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico
15.
Eur J Pharmacol ; 971: 176439, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38401605

RESUMEN

AIMS: Ischemic stroke accounts for 87% of all strokes, and its death and disability bring a huge burden to society. Brain injury caused by ischemia-reperfusion (I/R) is also a major difficulty in clinical treatment and prognosis. Sophoricoside (SOP) is an isoflavone glycoside isolated from the seed of medical herb Sophora japonica L. Previously, SOP was found to be effective in anti-inflammation and glucose-lipid metabolism-related diseases. In order to investigate whether SOP has a regulatory effect on cerebral I/R injury, we conducted this study. METHODS: Here, by application of SOP into MCAO (transient middle cerebral artery occlusion)-induced mice and OGD/R (oxygen glucose deprivation/reperfusion)-induced primary neurons, the regulation effects of SOP was analyzed by detecting neurological score of post-stroke mice, phenotypes of brains and brain sections, cell viabilities, and apoptosis- and inflammation-regulation. RNA sequencing and molecular biology experiments were performed to explore the mechanism of SOP regulating cerebral I/R injury. RESULTS: SOP administration decreased the infarct size, neurological deficit score, neuronal cell injury, inflammation and apoptosis. Mechanistically, SOP exerted its protective effect by activating the AMP-activated protein kinase (AMPK) signaling pathway. CONCLUSION: SOP inhibits cerebral I/R injury by promoting the phosphorylation of AMPK.


Asunto(s)
Benzopiranos , Isquemia Encefálica , Daño por Reperfusión , Accidente Cerebrovascular , Ratones , Animales , Proteínas Quinasas Activadas por AMP/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Isquemia Encefálica/metabolismo , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/metabolismo , Glucosa/metabolismo , Inflamación , Apoptosis
16.
Environ Sci Technol ; 58(9): 4145-4154, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38381076

RESUMEN

The deactivation of selective catalytic reduction (SCR) catalysts caused by alkali metal poisoning remains an insurmountable challenge. In this study, we examined the impact of Na poisoning on the performance of Fe and Mo co-doped TiO2 (FeaMobTiOx) catalysts in the SCR reaction and revealed the related alkali resistance mechanism. On the obtained Fe1Mo2.6TiOx catalyst, the synergistic catalytic effect of uniformly dispersed FeOx and MoOx species leads to remarkable catalytic activity, with over 90% NO conversion achieved in a wide temperature range of 210-410 °C. During the Na poisoning process, Na ions predominantly adsorb on the MoOx species, which exhibit stronger alkali resistance, effectively safeguarding the FeOx species. This preferential adsorption minimizes the negative effect of Na poisoning on Fe1Mo2.6TiOx. Moreover, Na poisoning has little influence on the Eley-Rideal reaction pathway involving adsorbed NHx reacting with gaseous NOx. After Na poisoning, the Lewis acid sites were deteriorated, while the abundant Brønsted acid sites ensured sufficient NHx adsorption. As a benefit from the self-defense effects of active MoOx species for alkali capture, FeaMobTiOx exhibits exceptional alkali resistance in the SCR reaction. This research provides valuable insights for the design of highly efficient and alkali-resistant SCR catalysts.


Asunto(s)
Álcalis , Amoníaco , Catálisis , Ácidos de Lewis , Metales
17.
Quant Imaging Med Surg ; 14(2): 1803-1819, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38415139

RESUMEN

Background: The heterogeneity of uterine fibroids in magnetic resonance imaging (MRI) is complex for a subjective visual evaluation, therefore it is difficult for an accurate prediction of the efficacy of high intensity focused ultrasound (HIFU) ablation in fibroids before the treatment. The purpose of this study was to set up a radiomics model based on MRI T2-weighted imaging (T2WI) for predicting the efficacy of HIFU ablation in uterine fibroids, and it would be used in preoperative screening of the fibroids for achieving high non-perfused volume ratio (NPVR). Methods: A total of 178 patients with uterine fibroids were consecutively enrolled and treated with ultrasound-guided HIFU under conscious sedation between February 2017 and December 2021. Among them, 96 patients with 108 uterine fibroids with high ablation efficacy (NPVR ≥80%, h_NPVR) and 82 patients with 92 fibroids with lower ablation efficacy (NPVR <80%, l_NPVR) were retrospectively analyzed. The transverse T2WI images of fibroids were selected, and the fibroids were delineated slice by slice using ITK-SNAP software. The radiomics analysis was performed to find the imaging biomarker for the construction of a predicting model for the evaluation of the ablation efficacy, including the feature extraction, feature selection and model construction. The prediction model was built by logistic regression and assessed by receiver operating characteristic (ROC) curve, and the prediction efficiency of the two models was compared by Delong test. The ratio of the training set to the testing set was 8:2. Results: The logistic regression model showed that the mean area under the curve (AUC) of the training set was 0.817 [95% confidence interval (CI): 0.755-0.882], and the testing set was 0.805 (95% CI: 0.670-0.941), respectively, which indicated a strong classification ability. The Delong test showed that there was no significant difference in the area under the ROC curve between the training set and testing set (P>0.05). Conclusions: The radiomics model based on T2WI is feasible and effective for predicting the efficacy of HIFU ablation in treatment of uterine fibroids.

18.
J Mater Chem B ; 12(3): 762-771, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38167689

RESUMEN

For hydrogel-based flexible sensors, it is a challenge to enhance the stability at sub-zero temperatures while maintaining good self-healing properties. Herein, an anti-freezing nanocomposite hydrogel with self-healing properties and conductivity was designed by introducing cellulose nanocrystals (CNCs) and phytic acid (PA). The CNCs were grafted with polypyrrole (PPy) by chemical oxidation, which were used as the nanoparticle reinforcement phase to reinforce the mechanical strength of hydrogels (851.8%). PA as a biomass material could form strong hydrogen bond interactions with H2O molecules, endowing hydrogels with prominent anti-freezing properties. Based on the non-covalent interactions, the self-healing rate of the hydrogels reached 92.9% at -15 °C as the content of PA was 40.0 wt%. Hydrogel-based strain sensors displayed high sensitivity (GF = 0.75), rapid response time (350 ms), good conductivity (3.1 S m-1) and stability at -15 °C. Various human movements could be detected by using them, including small (smile and frown) and large changes (elbow and knee bending). This work provides a promising method for the development of flexible wearable sensors that work stably in frigid environments.


Asunto(s)
Nanopartículas , Polímeros , Humanos , Nanogeles , Ácido Fítico , Celulosa , Pirroles , Hidrogeles
19.
Sci Rep ; 14(1): 686, 2024 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-38182722

RESUMEN

High altitude exposure increases the risk of myocardial ischemia (MI) and subsequent cardiovascular death. Machine learning techniques have been used to develop cardiovascular disease prediction models, but no reports exist for high altitude induced myocardial ischemia. Our objective was to establish a machine learning-based MI prediction model and identify key risk factors. Using a prospective cohort study, a predictive model was developed and validated for high-altitude MI. We consolidated the health examination and self-reported electronic questionnaire data (collected between January and June 2022 in 920th Joint Logistic Support Force Hospital of china) of soldiers undergoing high-altitude training, along with the health examination and second self-reported electronic questionnaire data (collected between December 2022 and January 2023) subsequent to their completion on the plateau, into a unified dataset. Participants were subsequently allocated to either the training or test dataset in a 3:1 ratio using random assignment. A predictive model based on clinical features, physical examination, and laboratory results was designed using the training dataset, and the model's performance was evaluated using the area under the receiver operating characteristic curve score (AUC) in the test dataset. Using the training dataset (n = 2141), we developed a myocardial ischemia prediction model with high accuracy (AUC = 0.86) when validated on the test dataset (n = 714). The model was based on five laboratory results: Eosinophils percentage (Eos.Per), Globulin (G), Ca, Glucose (GLU), and Aspartate aminotransferase (AST). Our concise and accurate high-altitude myocardial ischemia incidence prediction model, based on five laboratory results, may be used to identify risks in advance and help individuals and groups prepare before entering high-altitude areas. Further external validation, including female and different age groups, is necessary.


Asunto(s)
Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Femenino , Humanos , Estudios de Cohortes , Altitud , Estudios Prospectivos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiología , Aprendizaje Automático
20.
J Hazard Mater ; 466: 133606, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38286048

RESUMEN

Direct photocatalytic reduction of toxic formaldehyde (HCHO) in value-added chemicals and fuels is promising because that not only abates the environmental pollution, but also solves the energy shortage. Herein, self-supported MoO2 and MoO3 nanoparticles growing on Mo meshes were comparatively applied to the photocatalytic conversion of HCHO. Under UV-visble lights, MoO2 reduces HCHO in methanol (CH3OH) while MoO3 oxidizes HCHO in carbon oxide and water. Their contrary photocatalytic capacities were revealed. Compared with MoO3, the lower work function of MoO2 enables an electron-rich interface, realizing a complete reduction of 30 ppm HCHO to CH3OH in 30 min. Theoretical calculations clarify that a large number of delocalized electrons on MoO2 attracts HCHO molecule and activates its CO bond, facilitating subsequent hydrogenation and reduction of HCHO to CH3OH. As for MoO3, the wider bandgap and higher potential of valence band govern the photocatalytic oxidation of HCHO.

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