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Alpinia oxyphylla is famous for its neuroprotective and memory-improving effects. A crude polysaccharide AO70 from A. oxyphylla remarkably ameliorated neuroinflammation and cognitive dysfunction in Alzheimer's disease mice. This study aimed to explore the bioactive component of AO70 and its mechanism of action. A homogeneous polysaccharide (AOP70-1) rich in arabinose and xylose was purified from AO70, which was consisted of α-L-Araf-(1â, â5)-α-L-Araf-(1â, ß-D-Xylp-(1â,â2,4)-ß-D-Xylp-(1â, â2,3,4)-ß-D-Xylp-(1â, α-L-Rhap-(1â, α-D-Manp-(1â, â4)-α-D-Glcp-(1â, â4)-α-D-GlcpA-(1â, ß-D-Galp-(1â, â2)-α-D-Galp-(1â, â6)-α-D-Galp-(1 â and â3,6)-α-D-Manp-(1 â. AOP70-1 (2.5, 5, 10 µM) significantly suppressed NO, IL-1ß, and TNF-α production in a concentration-dependent manner and inhibited the migration of BV2 microglia. AOP70-1 inhibited LPS-mediated activation of Toll-like receptor 4 (TLR4), myeloid differentiation primary response protein (MyD88), and nuclear factor kappa B (NF-κB). Moreover, AOP70-1 exerted neuroprotection on SH-SY5Y cells and primary neurons by reducing neuronal apoptosis (72 %, 44 %), alleviating ROS accumulation (63 %, 55 %), and improving mitochondrial membrane potential (63 %, 77 %). Overall, AOP70-1 is one of the major bioactive components in AO70 from A. oxyphylla, which has great potential in the prevention and treatment of neuroinflammation.
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There are two key signatures of pediatric cancers: (a) higher prevalence of germline alterations and (b) heterogeneity in alteration types. Recent population-based assessments have demonstrated that children with birth defects (BDs) are more likely to develop cancer even without chromosomal anomalies; therefore, explorations of genetic alterations in children with BDs and cancers could provide new insights into the underlying mechanisms for pediatric tumor development. We performed whole-genome sequencing (WGS) on blood-derived DNA for 1556 individuals without chromosomal anomalies, including 454 BD probands with at least one type of malignant tumor, 757 cancer-free children with BDs, and 345 healthy individuals, focusing on copy number variation (CNV) analysis. Roughly half of the children with BD-cancer have CNVs that are not identified in BD-only/healthy individuals, and CNVs are not evenly distributed among these patients. Strong heterogeneity was observed, with a limited number of cancer predisposition genes containing CNVs in more than three patients. Moreover, functional enrichments of genes with CNVs showed that dozens of patients have variations related to the same biological pathways, such as deletions of genes with neurological functions and duplications of immune response genes. Phenotype clustering uncovered recurrences of patients with sarcoma: A notable enrichment was observed involving non-coding RNA regulators, showing strong signals related to growth and cancer regulations in functional analysis. In conclusion, we conducted one of the first genomic studies exploring the impact of CNVs on cancer development in children with BDs, unveiling new insights into the underlying biological processes.
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Thrombosis and inflammation are primary contributors to the onset and progression of ischemic stroke. The contact-kinin pathway, initiated by plasma kallikrein (PK) and activated factor XII (FXIIa), functions bidirectionally with the coagulation and inflammation cascades, providing a novel target for therapeutic drug development in ischemic stroke. In this study, we identified a bat-derived oligopeptide from Myotis myotis (Borkhausen, 1797), designated LE6 (Leu-Ser-Glu-Glu-Pro-Glu, 702 Da), with considerable potential in stroke therapy due to its effects on the contact kinin pathway. Notably, LE6 demonstrated significant inhibitory effects on PK and FXIIa, with inhibition constants of 43.97 µmol/L and 6.37 µmol/L, respectively. In vitro analyses revealed that LE6 prolonged plasma recalcification time and activated partial thromboplastin time. In murine models, LE6 effectively inhibited carrageenan-induced mouse tail thrombosis, FeCl 3-induced carotid artery thrombosis, and photochemically induced intracerebral thrombosis. Furthermore, LE6 significantly decreased inflammation and stroke injury in transient middle cerebral artery occlusion models. Notably, the low toxicity, hemolytic activity, and bleeding risk of LE6, along with its synthetic simplicity, underscore its clinical applicability. In conclusion, as an inhibitor of FXIIa and PK, LE6 offers potential therapeutic benefits in stroke treatment by mitigating inflammation and preventing thrombus formation.
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Oligopéptidos , Accidente Cerebrovascular , Animales , Ratones , Oligopéptidos/farmacología , Accidente Cerebrovascular/tratamiento farmacológico , Quirópteros , Trombosis , Inflamación , Masculino , Antiinflamatorios/farmacologíaRESUMEN
This article examines the development of primary English education from teachers' and students' perspectives; this is done by investigating environment, curriculum and teacher and students' information. The study was carried out with 42 primary English teachers and 404 primary students from 90 urban and rural primary schools in 13 regions in the Hunan Province, China, the participants engaged in the questionnaire tasks to investigate the present status and problems with primary English education in the Hunan Province. Based on the assessment indicators through CIPP model, combining educational theory and sustainable development theory, the present study develops a primary school English education evaluation model and conducts a practical investigation of primary school English education in the Hunan Province, based on the established model. The findings indicate that the quality of teachers has improved, teaching methods and teaching equipment have become diversified, and student interests and English proficiencies have increased. However, there are still deficiencies in the implementation of Primary English Education in the Hunan Province. For instance, certain schools improperly implement national policies, resulting in imbalanced education. Additionally, educational inequality persists due to disparities in family economic status and importance. Moreover, regional, ideological, and management factors contribute to uneven allocation of educational resources. Furthermore, significant disparities exist between urban and rural areas in terms of teacher qualifications, teaching quality, and school operating hours. The article proposes enhancing awareness of sustainable development, strengthening supervision, and seeking educational and policy support to facilitate the sustainable development of primary English education.
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BACKGROUND: Post-stroke infection is the most common complication of stroke and poses a huge threat to patients. In addition to prolonging the hospitalization time and increasing the medical burden, post-stroke infection also significantly increases the risk of disease and death. Clarifying the risk factors for post-stroke infection in patients with acute ischemic stroke (AIS) is of great significance. It can guide clinical practice to perform corresponding prevention and control work early, minimizing the risk of stroke-related infections and ensuring favorable disease outcomes. AIM: To explore the risk factors for post-stroke infection in patients with AIS and to construct a nomogram predictive model. METHODS: The clinical data of 206 patients with AIS admitted to our hospital between April 2020 and April 2023 were retrospectively collected. Baseline data and post-stroke infection status of all study subjects were assessed, and the risk factors for post-stroke infection in patients with AIS were analyzed. RESULTS: Totally, 48 patients with AIS developed stroke, with an infection rate of 23.3%. Age, diabetes, disturbance of consciousness, high National Institutes of Health Stroke Scale (NIHSS) score at admission, invasive operation, and chronic obstructive pulmonary disease (COPD) were risk factors for post-stroke infection in patients with AIS (P < 0.05). A nomogram prediction model was constructed with a C-index of 0.891, reflecting the good potential clinical efficacy of the nomogram prediction model. The calibration curve also showed good consistency between the actual observations and nomogram predictions. The area under the receiver operating characteristic curve was 0.891 (95% confidence interval: 0.839-0.942), showing predictive value for post-stroke infection. When the optimal cutoff value was selected, the sensitivity and specificity were 87.5% and 79.7%, respectively. CONCLUSION: Age, diabetes, disturbance of consciousness, NIHSS score at admission, invasive surgery, and COPD are risk factors for post-stroke infection following AIS. The nomogram prediction model established based on these factors exhibits high discrimination and accuracy.
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Machine learning can be used to define subtypes of psychiatric conditions based on shared biological foundations of mental disorders. Here we analyzed cross-sectional brain images from 4,222 individuals with schizophrenia and 7038 healthy subjects pooled across 41 international cohorts from the ENIGMA, non-ENIGMA cohorts and public datasets. Using the Subtype and Stage Inference (SuStaIn) algorithm, we identify two distinct neurostructural subgroups by mapping the spatial and temporal 'trajectory' of gray matter change in schizophrenia. Subgroup 1 was characterized by an early cortical-predominant loss with enlarged striatum, whereas subgroup 2 displayed an early subcortical-predominant loss in the hippocampus, striatum and other subcortical regions. We confirmed the reproducibility of the two neurostructural subtypes across various sample sites, including Europe, North America and East Asia. This imaging-based taxonomy holds the potential to identify individuals with shared neurobiological attributes, thereby suggesting the viability of redefining existing disorder constructs based on biological factors.
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Algoritmos , Sustancia Gris , Imagen por Resonancia Magnética , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/patología , Masculino , Femenino , Adulto , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Aprendizaje Automático , Persona de Mediana Edad , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Estudios Transversales , Europa (Continente) , Neuroimagen , Reproducibilidad de los Resultados , América del Norte , Hipocampo/diagnóstico por imagen , Hipocampo/patologíaRESUMEN
OBJECTIVES: To compare color Doppler ultrasound and contrast-enhanced ultrasound (CEUS) in evaluating vascular invasion in pancreatic ductal adenocarcinoma (PDAC). MATERIALS AND METHODS: This retrospective study included 210 patients with PDAC who were evaluated by color Doppler ultrasound, CEUS, and contrast-enhanced computed tomography (CECT) at our institution between January 2017 and December 2020. Pathologic results were used as the gold standard in patients who underwent surgical and intraoperative exploration. For nonsurgical patients, CECT results were used as the reference standard. The vessels evaluated included those in the peripancreatic arterial system and venous system. The diagnostic performances of color Doppler ultrasound and CEUS for vascular invasion were compared. RESULTS: In 51 patients who underwent surgery and intraoperative exploration, color Doppler ultrasound and CEUS differed only in assessing venous system invasion in patients with PDAC of the pancreatic body and tail, with the former being superior to the latter. In 159 nonsurgical patients, there was no difference between CEUS and color Doppler ultrasound in assessing superior mesenteric arteriovenous invasion. CEUS was superior to color Doppler ultrasound in evaluating the celiac artery and its branches, with an accuracy of up to 97.8% for some vessels. Color Doppler ultrasound was ideal for evaluating the splenic and portal veins. CONCLUSION: CEUS is more suitable for the evaluation of peripancreatic arteries than color Doppler. CEUS combined with color Doppler ultrasound can be used as a potential supplement to CECT and is also expected to be used to evaluate vascular invasion of PDAC after chemotherapy. CRITICAL RELEVANCE STATEMENT: Contrast-enhanced US and color Doppler in the assessment of vascular invasion in pancreatic ductal adenocarcinoma have their respective advantages, through standardized ultrasound processes are expected to improve the efficiency of inspection. KEY POINTS: Contrast-enhanced US has unique advantages in assessing pancreatic ductal adenocarcinoma invasion of the celiac artery. Doppler imaging is of high value in assessing venous system invasion. Standardization of ultrasound imaging procedures for pancreatic ductal adenocarcinoma is expected to improve efficiency.
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Background: Age is a known prognostic factor for various cancers. However, few studies explored the association between age and prognosis of esophageal cancer (EC) comprehensively, especially from a nonlinear perspective. Design: Retrospective cohort study. Objectives: Our study aims to explore the possible nonlinear associations between age and prognosis in EC patients receiving curative surgery and radiotherapy, respectively. Methods: Cox regression models with restricted cubic splines were used to model the possible nonlinear relationship between age and prognosis in surgical and radiotherapy groups, respectively. Surveillance, Epidemiology, and End Results database was used to validate the age-prognosis patterns found in Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group database. Age-prognosis patterns were further validated by survival comparisons between different age subgroups and in subsequent sensitivity and subgroup analyses. Primary endpoint is overall survival. Secondary endpoints are cancer-specific survival and progression-free survival. Results: A total of 56,457 patients from two large cancer databases were included. Patients receiving surgery and radiotherapy showed two distinct nonlinear age-prognosis patterns. Age showed a U-/J-shaped association with prognosis in the radiotherapy group, with a nadir at approximately 65- to 70-years-old. As for surgical cohort, relative risk for all-cause mortality and cancer-specific mortality increased with age with p for nonlinearity <0.05. The above age-prognosis relationships were validated by sensitivity, subgroup, and comparative survival analyses. Youngest and middle-aged patients showed better survival results compared to that of other age subgroups in surgical and radiotherapy cohorts, respectively [Radiotherapy, youngest/middle: hazard ratio (HR) = 1.06, 95% confidence interval (CI): 1.02-1.10, p = 0.001; Radiotherapy, oldest/middle: HR = 1.21, 95% CI: 1.18-1.24, p < 0.001; Surgical, middle/youngest: HR = 1.19, 95% CI: 1.14-1.25, p < 0.001; surgical, oldest/youngest: HR = 1.85, 95% CI: 1.75-1.97, p < 0.001]. Conclusion: Patients receiving surgery and radiotherapy showed two distinct age-prognosis patterns. Younger and middle-aged patients were associated with better survival in surgical and radiotherapy groups, respectively. Additional studies are warranted to explore the underlying mechanisms and clinical implications of this phenomenon.
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Schizophrenia lacks a clear definition at the neuroanatomical level, capturing the sites of origin and progress of this disorder. Using a network-theory approach called epicenter mapping on cross-sectional magnetic resonance imaging from 1124 individuals with schizophrenia, we identified the most likely "source of origin" of the structural pathology. Our results suggest that the Broca's area and adjacent frontoinsular cortex may be the epicenters of neuroanatomical pathophysiology in schizophrenia. These epicenters can predict an individual's response to treatment for psychosis. In addition, cross-diagnostic similarities based on epicenter mapping over of 4000 individuals diagnosed with neurological, neurodevelopmental, or psychiatric disorders appear to be limited. When present, these similarities are restricted to bipolar disorder, major depressive disorder, and obsessive-compulsive disorder. We provide a comprehensive framework linking schizophrenia-specific epicenters to multiple levels of neurobiology, including cognitive processes, neurotransmitter receptors and transporters, and human brain gene expression. Epicenter mapping may be a reliable tool for identifying the potential onset sites of neural pathophysiology in schizophrenia.
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Imagen por Resonancia Magnética , Neuroimagen , Esquizofrenia , Esquizofrenia/patología , Esquizofrenia/diagnóstico por imagen , Humanos , Neuroimagen/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Femenino , Adulto , Mapeo Encefálico/métodos , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Persona de Mediana EdadRESUMEN
Emerging organophosphate flame retardants (eOPFRs) have attracted attention in recent times and are expected to gain extensive usage in the coming years. However, they may have adverse effects on organisms. Due to their novel nature, there are few relevant articles dealing with toxicological studies of the above eOPFRs, especially their information on the perturbation of cellular metabolism, which is, thus far, marginally understood. Our research initially assessed the cytotoxicity of eOPFRs, which include compounds like cresyl diphenyl phosphate (CDP), resorcinol bis(diphenyl phosphate) (RDP), triallyl phosphate (TAP), and pentaerythritol phosphate alcohol (PEPA). This evaluation was conducted using the methyl thiazolyl tetrazolium (MTT) assay. Subsequently, we utilized a gas chromatography/mass spectrometry (GC/MS)-based metabolomic approach to investigate the metabolic disruptions induced by these four eOPFRs in A549 cells. The MTT results showed that, at high concentrations of 1 mM, their cytotoxicity was ranked as CDP > TAP > RDP > PEPA. In addition, metabolic studies at low concentrations of 10 µM showed that the metabolic interference of CDP, TAP, and PEPA focuses on oxidative stress, amino acid metabolism, and energy metabolism, while RDP mainly affects energy metabolism-galactose metabolism and gluconeogenesis. Therefore, from the perspective of cytotoxicity and metabolic analysis, RDP may be a more promising alternative. Our experiments provide important insights into the possible metabolic effects of potential toxic substances and complement the evidence on the human health risks of eOPFRs.
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Large sample datasets have been regarded as the primary basis for innovative discoveries and the solution to missing heritability in genome-wide association studies. However, their computational complexity cannot consider all comprehensive effects and all polygenic backgrounds, which reduces the effectiveness of large datasets. To address these challenges, we included all effects and polygenic backgrounds in a mixed logistic model for binary traits and compressed four variance components into two. The compressed model combined three computational algorithms to develop an innovative method, called FastBiCmrMLM, for large data analysis. These algorithms were tailored to sample size, computational speed, and reduced memory requirements. To mine additional genes, linkage disequilibrium markers were replaced by bin-based haplotypes, which are analyzed by FastBiCmrMLM, named FastBiCmrMLM-Hap. Simulation studies highlighted the superiority of FastBiCmrMLM over GMMAT, SAIGE and fastGWA-GLMM in identifying dominant, small α (allele substitution effect), and rare variants. In the UK Biobank-scale dataset, we demonstrated that FastBiCmrMLM could detect variants as small as 0.03% and with α ≈ 0. In re-analyses of seven diseases in the WTCCC datasets, 29 candidate genes, with both functional and TWAS evidence, around 36 variants identified only by the new methods, strongly validated the new methods. These methods offer a new way to decipher the genetic architecture of binary traits and address the challenges outlined above.
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Algoritmos , Estudio de Asociación del Genoma Completo , Estudio de Asociación del Genoma Completo/métodos , Humanos , Modelos Logísticos , Estudios de Casos y Controles , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple , Genómica/métodos , Simulación por Computador , Haplotipos , Modelos GenéticosRESUMEN
BACKGROUND: Ginsenoside Rg3 is a component of ginseng that protects against myocardial ischemia/reperfusion (MI/R) injury. Ferroptosis is a new form of cell death characterized by oxidative damage to phospholipids. The purpose of this study was to examine the role and of ginsenoside Rg3 in MI/R and the mechanism. METHODS: A mouse model of left anterior descending (LAD) ligation-induced myocardial ischemia/reperfusion (MI/R) injury and oxygen-glucose deprivation/reperfusion (OGD/R) were used as in vitro and in vivo models, respectively. Echocardiographic analysis, 2,3,5-triphenyltetrazolium chloride (TTC) staining and hematoxylin-eosin (H&E) staining were used to assess the cardioprotective effects of ginsenoside Rg3. Western blotting, biochemical analysis, small interfering RNA analysis and molecular docking were performed to examine the underlying mechanism. RESULTS: Ginsenoside Rg3 improved cardiac function and infarct size in mice with MI/R injury. Moreover, ginsenoside Rg3 increased the expression of the ferroptosis-related protein GPX4 and inhibited iron deposition in mice with MI/R injury. Ginsenoside Rg3 also activated the Nrf2 signaling pathway. Ginsenoside Rg3 attenuated myocardial ischemia/reperfusion-induced ferroptosis via the Nrf2 signaling pathway. Notably, ginsenoside Rg3 regulated the keap1/Nrf2 signaling pathway to attenuate OGD/R-induced ferroptosis in H9C2 cells. Taken together, ginsenoside Rg3 attenuated myocardial ischemia/reperfusion-induced ferroptosis via the keap1/Nrf2/GPX4 signaling pathway. CONCLUSIONS: Our findings demonstrated that ginsenoside Rg3 ameliorate MI/R-induced ferroptosis via the keap1/Nrf2/GPX4 signaling pathway.
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Ferroptosis , Ginsenósidos , Proteína 1 Asociada A ECH Tipo Kelch , Ratones Endogámicos C57BL , Daño por Reperfusión Miocárdica , Factor 2 Relacionado con NF-E2 , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Transducción de Señal , Ginsenósidos/farmacología , Animales , Ferroptosis/efectos de los fármacos , Ratones , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Factor 2 Relacionado con NF-E2/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Transducción de Señal/efectos de los fármacos , Masculino , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Modelos Animales de EnfermedadRESUMEN
Phosphaphenalenes, extended π conjugates with the incorporation of phosphorus, are attractive avenues towards molecular materials for the applications in organic electronics, but their electron accepting ability have not been investigated. Herein we present systematic studies on the reductive behavior of a representative phosphaphenalene and its oxide by chemical and electrochemical methods. The chemical reduction of the phosphaphenalene by alkali metals reveals the facile P-C bond cleavage to form phosphaphenalenide anion, which functions as a transfer block for structure modification on the phosphorus atom. In contrast, the pentavalent P-oxide reacts with one or two equivalents of elemental sodium to form stable radical anion and dianion salts, respectively.
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Magneto-controlling micro-nano materials' motion is a promising way that enable the noncontact, remote, and nondestructive controlling of their macrostructure as well as functionalities. Here, an optical microscope with an electromagnet was constructed toin-situmonitor the magneto-controlled motion process microscopically. Taking micro-nano graphite flake (MGF) as a model system, we experimentally demonstrate the key factors that influence the magneto-controlling of materials' motion. First, the product of intensity and gradient of the magnetic field (B∇B) has been confirmed as the dominant driving force and the flipping direction of the MGFs is accordingly determined by the vector direction ofB×∇B. Second, quantitatively comparative experiments further revealed that the threshold driving force has an exponential relationship with the structural aspect ratio (b/a) of MGFs. Third, the critical magneto-driving force is found as proportional to the viscosity of the solvent. Accordingly, a dynamic model is developed that describes the flip of the diamagnetic flake under external magnetic field excitation considering the shape factor. It is shown experimentally that the model accurately predicts the flip dynamics of the flake under different magnetic field conditions. In addition, we also discovered the delay effect, multiple cycle acceleration effect, and the fatigue effects due to gas adsorption in magneto-controlled MGFs flipping. These findings can be used to achieve magneto-controlling materials' macrostructure as well as their functionalities.
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Emotion recognition and the resulting responses are important for survival and social functioning. However, how socially derived information is processed for reliable emotion recognition is incompletely understood. Here, we reveal an evolutionarily conserved long-range inhibitory/excitatory brain network mediating these socio-cognitive processes. Anatomical tracing in mice revealed the existence of a subpopulation of somatostatin (SOM) GABAergic neurons projecting from the medial prefrontal cortex (mPFC) to the retrosplenial cortex (RSC). Through optogenetic manipulations and Ca2+ imaging fiber photometry in mice and functional imaging in humans, we demonstrate the specific participation of these long-range SOM projections from the mPFC to the RSC, and an excitatory feedback loop from the RSC to the mPFC, in emotion recognition. Notably, we show that mPFC-to-RSC SOM projections are dysfunctional in mouse models relevant to psychiatric vulnerability and can be targeted to rescue emotion recognition deficits in these mice. Our findings demonstrate a cortico-cortical circuit underlying emotion recognition.
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Emociones , Corteza Prefrontal , Animales , Emociones/fisiología , Corteza Prefrontal/fisiología , Ratones , Masculino , Humanos , Neuronas GABAérgicas/fisiología , Vías Nerviosas/fisiología , Somatostatina/metabolismo , Reconocimiento en Psicología/fisiología , Ratones Endogámicos C57BL , Optogenética , Femenino , Giro del Cíngulo/fisiologíaRESUMEN
The preservation or removal of apical meristem in Leymus chinensis is contingent upon grazing intensity and has a significant impact on above- and belowground biomass, nutritive value, and sustainability of L. chinensis grassland. However, this topic remains understudied. Therefore, a manipulative trial was conducted to induce grazing defoliation through mowing, where two post-grazing heights (preservation or removal of the apical meristem) and four pre-grazing plant heights (i.e., 18, 24, 31, and 35 cm) are combined factorially to create gradients of grazing intensities, resulting in a total of eight treatments. Additionally, two identical control treatments are also incorporated. Our results showed that apical meristem removal at various pre-grazing heights resulted in varying degrees of increased grazing intensities, thereby enhancing the nutritive value of L. chinensis. However, this practice also led to detrimental effects on the plant's carbohydrates reserve as well as herbage mass. The results indicated that although defoliation in treatments involving apical meristem removal resulted in the highest number of frequent cuttings, it did not confer any advantages in terms of herbage mass and nutrient preserves, except for herbage nutritive values when compared to treatments involving apical meristem preservation. The apical meristem preservation treatments demonstrated the highest CP yield over a 2-year period compared to the apical meristem removal treatments. Furthermore, within these apical meristem preservation treatments, only when the pre-grazing height is 35 cm and post-grazing height is 17 cm, there is no significant decrease in above- and belowground biomass. This establishes this specific defoliation regime as an optimal and effective management strategy for L. chinensis grassland.
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Engineering atomic vacancies in metal sulfide semiconductors allows for the efficient tuning of their electronic and chemical properties. In this work, we synthesized hollow tubular structures constructed by bimetallic ZnIn2S4 using a metal-organic framework (MOF) as the template. We found that the sulfur vacancies in ZnIn2S4 enabled extremely fast NO2 detection with high response at room temperature (RT), and the material with high sulfur vacancy content delivers a 2 times higher response to 10 ppm NO2 than the device with low sulfur vacancy content. To unveil the crucial role played by sulfur vacancies, DFT calculations were conducted to reveal that sulfur vacancies greatly enhance the interaction and electron transfer between ZnIn2S4 and NO2. This study will provide hints for the engineering of bimetallic sulfide materials for low-power gas sensors at RT.
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BACKGROUND: Definitive chemoradiotherapy is one of the primary treatment modalities for older patients with esophageal cancer (EC). However, the evolution of prognosis over time and the factors affected non-EC deaths remain inadequately studied. We examined the conditional survival and annual hazard of death in older patients with EC after chemoradiotherapy. METHODS: We collected data from patients aged 65 or older with EC registered in the Surveillance, Epidemiology, and End Results database during 2000-2019. Conditional survival was defined as the probability of survival given a specific time survived. Annual hazard of death was defined the yearly event rate. Restricted cubic spline (RCS) analysis identified the association of age at diagnosis with mortality. RESULTS: Among 3739 patients, the 3-year conditional overall survival increased annually by 7-10%. Non-EC causes accounted for 18.8% of deaths, predominantly due to cardio-cerebrovascular diseases. The hazard of death decreased from 40 to 10% in the first 6 years and then gradually increased to 20% in the tenth year. Non-EC causes surpassed EC causes in hazard starting 5 years post-treatment. RCS indicated a consistent increase in death hazard with advancing age, following a linear relationship. The overall cohort was divided into two groups: 65-74 and ≥ 75 years old, with the ≥ 75-year-old group showing poorer survival and earlier onset of non-EC deaths (HR = 1.36, 95% CI: 1.15-1.62, P < 0.001). Patients with early-stage disease (I-II) had higher risks of death from non-EC causes (HR = 0.82, 95% CI: 0.68-0.98, P = 0.035). Tumor histology had no significant impact on non-EC death risk (HR = 1.17, 95% CI: 0.98-1.39, P = 0.081). CONCLUSIONS: Survival probability increases with time for older patients with EC treated with chemoradiotherapy. Clinicians and patients should prioritize managing and preventing age-related comorbidities, especially in older cohorts and those with early-stage disease.
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Neoplasias Esofágicas , Humanos , Anciano , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Quimioradioterapia/métodos , Pronóstico , ComorbilidadRESUMEN
Single-atom catalysts (SACs) hold great promise in highly sensitive and selective gas sensors due to their ultrahigh atomic efficiency and excellent catalytic activity. However, due to the extremely high surface energy of SACs, it is still a huge challenge to synthesize a stable single-atom metal on sensitive materials. Here, we report an atomic layer deposition (ALD) strategy for the elaborate synthesis of single-atom Pt on oxygen vacancy-rich Fe2O3 nanosheets (Pt-Fe2O3-Vo), which displayed ultrafast and sensitive detection to H2, achieving the stability of Pt single atoms. Gas-sensing investigation showed that the Pt-Fe2O3-Vo materials enabled a significantly enhanced response of 26.5-50 ppm of H2, which was 17-fold higher than that of pure Fe2O3, as well as ultrafast response time (2 s), extremely low detection limit (86 ppb), and improved stability. The experimental and density functional theory (DFT) studies revealed that the abundant oxygen vacancy sites of Fe2O3 contributed to stabilizing the Pt atoms via electron transfer. In addition, the stabilized Pt atoms also greatly promote the electron transfer of H2 molecules to Fe2O3, thereby achieving an excellent H2 sensing performance. This work provides a potential strategy for the development of highly selective and stable chemical sensors.
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Compuestos Férricos , Hidrógeno , Nanoestructuras , Oxígeno , Platino (Metal) , Platino (Metal)/química , Oxígeno/química , Hidrógeno/química , Compuestos Férricos/química , Nanoestructuras/química , Teoría Funcional de la Densidad , Catálisis , Límite de DetecciónRESUMEN
Precise regulation of the active site structure is an important means to enhance the activity and selectivity of catalysts in CO2 electroreduction. Here, we creatively introduce anionic groups, which can not only stabilize metal sites with strong coordination ability but also have rich interactions with protons at active sites to modify the electronic structure and proton transfer process of catalysts. This strategy helps to convert CO2 into fuel chemicals at low overpotentials. As a typical example, a composite catalyst, CuO/Cu-NSO4/CN, with highly dispersed Cu(II)-SO4 sites has been reported, in which CO2 electroreduction to formate occurs at a low overpotential with a high Faradaic efficiency (-0.5â V vs. RHE, FEformate=87.4 %). Pure HCOOH is produced with an energy conversion efficiency of 44.3 % at a cell voltage of 2.8â V. Theoretical modeling demonstrates that sulfate promotes CO2 transformation into a carboxyl intermediate followed by HCOOH generation, whose mechanism is significantly different from that of the traditional process via a formate intermediate for HCOOH production.