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Although crystalline metal-organic frameworks (MOFs) have gained a great deal of interest in the field of proton conduction in recent years, the low stability and poor proton conductivity (σ) of some MOFs have hindered their future applications. As a result, resolving the issues listed above must be prioritized. Due to their exceptional structural stability, MOFs with ferrocene groups that exhibit particular physical and chemical properties have drawn a lot of attention. This study describes the effective preparation of a set of three-dimensional ferrocene-based MOFs, MIL-53-FcDC-Al/Ga and CAU-43, containing both main group metals and 1,1'-ferrocene dicarboxylic acid (H2FcDC). Multiple measurements, including powder X-ray diffraction (PXRD), infrared (IR), and scanning electron microscopy (SEM), confirmed that the addition of ferrocene groups enhanced the thermal, water, and acid-base stabilities of the three MOFs. Consequently, their proton-conductive behaviors were meticulously measured utilizing the AC impedance approach, and their best proton conductivities are 5.20 × 10-3, 2.31 × 10-3, and 1.72 × 10-4 S/cm at 100 °C/98% relative humidity (RH), respectively. Excitingly, MIL-53-FcDC-Al/Ga demonstrated an extraordinarily ultrahigh σ of above 10-4 S·cm-1 under 30 °C/98% RH. Using data from structural analysis, PXRD, SEM, thermogravimetry (TG), and activation energy, their proton transport mechanisms were thoroughly examined. The fact that these MOFs are notably easy to assemble, inexpensive, toxin-free, and stable will increase the range of practical uses for them.
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To date, developing crystalline proton-conductive metal-organic frameworks (MOFs) with an inherent excellent proton-conducting ability and structural stability has been a critical priority in addressing the technologies required for sustainable development and energy storage. Bearing this in mind, a multifunctional organic ligand, 3,4-dimethylthiophene[2,3-b]thiophene-2,5-dicarboxylic acid (H2DTD), was employed to generate two exceptionally stable three-dimensional porous Zr/Hf MOFs, [Zr6O4(OH)4(DTD)6]·5DMF·H2O (Zr-DTD) and [Hf6O4(OH)4(DTD)6]·4DMF·H2O (Hf-DTD), using solvothermal means. The presence of Zr6 or Hf6 nodes, strong Zr/Hf-O bonds, the electrical influence of the methyl group, and the steric effect of the thiophene unit all contribute to their structural stability throughout a wide pH range as well as in water. Their proton conductivity was fully examined at various relative humidities (RHs) and temperatures. Creating intricate and rich H-bonded networks between the guest water molecules, coordination solvent molecules, thiophene-S, -COOH, and -OH units within the framework assisted proton transfer. As a result, both MOFs manifest the maximum proton conductivity of 0.67 × 10-2 and 4.85 × 10-3 S·cm-1 under 98% RH/100 °C, making them the top-performing proton-conductive Zr/Hf-MOFs. Finally, by combining structural characteristics and activation energies, potential proton conduction pathways for the two MOFs were identified.
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Polyvinyl pyrrolidone (PVP) is doped to PbI2 and organic salt during two-step growth of halideperovskite. It is observed that PVP molecules can interact with both PbI2 and organic salt, reduce the aggregation and crystallization of the two, and then slow down the coarsening rate of perovskite. As doping concentration increases from 0 to 1 mM in organic salt, average crystallite size of perovskite decreases monotonously from 90 to 34 nm; Surface fluctuation reduces from 259.9 to 179.8 nm at first, and then increases; Similarly, surface roughness decreases from 45.55 to 26.64 nm at first, and then rises. Accordingly, a kind of "confinement effect" is resolved to crystallite growth and surface fluctuation/roughness, which helps to build compact and uniform perovskite film. Density of trap states (t-DOS) is cut down by ≈60% at moderate doping (0.2 mM). Due to the "confinement effect", power conversion efficiency of perovskite solar cells is improved from 19.46 (±2.80) % to 21.50 (±0.99) %, and further improved to 24.11% after surface modification. Meanwhile, "confinement effect" strengthens crystallite/grain boundaries and improves thermal stability of both film and device. T80 of device increases to 120 h, compared to 50 h for reference ones.
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An alkene-bridged thioether ligand (L) was designed and used for its first study within a polyoxometalate (POM) hybrid system, and a POM-based copper(I)-alkene compound [(CuIL)2(PVMoVI12O40)]·(CuIL) (1) was isolated and characterized by X-ray crystallography. A unique alkene-coordinating N(η2-CâC)N mode of L is observed, and the Cu centers are captured by σ2,π-L in a pocket fashion, giving birth to discrete [CuIL]+ cations and [(CuIL)2(PVMoVI12)]- anions. The ionic crystal exhibits solubility in aprotic polar solvents, and the electrospray ionization mass spectrometry is used to explore the nature of species present in the solution. It is found that the whole cluster [PVMoVI12]3- is completely present, and all the main peaks can be assigned to different charged fragments of the same parent cluster.
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BACKGROUND: Electronic cigarette (e-cig) use is increasing worldwide, especially among young individuals. Spirometry measures airflow obstruction and is the primary tool for diagnosing/monitoring respiratory diseases in clinical settings. This study aims to assess the effects of chronic e-cig exposure on spirometric traits, and directly compare to conventional combustible-cigarette (c-cig). METHODS: We employed an e- and c-cig aerosol generation system that resembled human smoking/vaping scenario. Fifty 6-week old C57BL/6 mice were equally divided into five groups and exposed to clean air (control), e-cig aerosol (low- and high-dose), and c-cig aerosol (low- and high-dose), respectively, for 10 weeks. Afterwards, growth trajectory, spirometry and pulmonary pathology were analyzed. RESULTS: Both e- and c-cig exposure slowed down growth and weight gain. Low dose e-cig exposure (1 h exposure per day) resulted in minimal respiratory function damage. At high dose (2 h exposure per day), e-cig exposure deteriorated 7 spirometry traits but by a smaller magnitude than c-cig exposure. For example, comparing to clean air controls, high dose e- and c-cig exposure increased inspiratory resistance by 24.3% (p = 0.026) and 66.7% (p = 2.6e-5), respectively. Low-dose e-cig exposure increased alveolar macrophage count but did not lead to airway remodeling. In contrast, even low-dose c-cig caused alveoli break down and thickening of the small airway, hallmarks of airway obstructive disease. CONCLUSIONS: We conducted well-controlled animal exposure experiments assessing chronic e-cig exposure's effects on spirometry traits. Further, mechanistic study characterized airway remodeling, alveolar tissue lesion and inflammation induced by e- and c-cig exposure. Our findings provided scientific and public health insights on e-cig's health consequences, especially in adolescent users.
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Sistemas Eletrônicos de Liberação de Nicotina , Lesão Pulmonar , Produtos do Tabaco , Humanos , Camundongos , Animais , Adolescente , Remodelação das Vias Aéreas , Camundongos Endogâmicos C57BL , Aerossóis e Gotículas Respiratórios , Lesão Pulmonar/induzido quimicamenteRESUMO
BACKGROUND: High-flow nasal cannula oxygen therapy (HFNC) is recommended for patients with COVID-19. However, the increasing use of HFNC brings a risk of delayed intubation. The optimal timing of switching from HFNC to invasive mechanical ventilation (IMV) remains unclear. An effective predictor is needed to assist in deciding on the timing of intubation. Respiratory rate and oxygenation (ROX) index, defined as (SpO2/FiO2) / respiratory rate, has already shown good diagnostic accuracy. Modified ROX (mROX) index, defined as (PaO2 /FiO2) / respiratory rate, might be better than the ROX index in predicting HFNC failure. OBJECTIVE: The aim was to evaluate the predictive value of mROX for HFNC failure in patients with COVID-19. METHODS: Severe or critical patients with COVID-19 treated with HFNC were enrolled in two clinical centers. Laboratory indicators, respiratory parameters, and mROX index at 0 h and 2 h after initial HFNC were collected. Based on the need for IMV after HFNC initiation, the patients were divided into an HFNC failure group and an HFNC success group. The predictive value of mROX index for IMV was evaluated by the area under the receiver operating characteristic curve (AUROC) and logistic regression analysis. We performed Kaplan-Meier survival analysis using the log-rank test. RESULTS: Sixty patients with COVID-19 (mean ± SD age, 62.8 ± 14.1 years; 42 patients were male) receiving HFNC were evaluated, including 18 critical and 42 severe cases. A total of 33 patients had hypertension; 14 had diabetes; 17 had chronic cardiac disease; 11 had chronic lung disease; 13 had chronic kidney disease; and 17 had a history of stroke. The AUROC of mROX index at 2 h was superior to that of other respiratory parameters to predict the need for IMV (0.959; p < 0.001). At the mROX index cutoff point of 4.45, predicting HFNC failure reached the optimal threshold, with specificity of 94% and sensitivity of 92%. Logistic regression analysis showed that 2-h mROX index < 4.45 was a protective factor for IMV (odd radio 0.18; 95% CI 0.05-0.64; p = 0.008). In the HFNC failure group, the median time from HFNC to IMV was 22.5 h. The 28-day mortality of the late intubation patients (≥ 22.5 h) was higher than that of the early intubation patients (< 22.5 h) (53.8% vs. 8.3%; p = 0.023). CONCLUSIONS: mROX at 2 h is a good early warning index of the need for IMV in patients with COVID-19 after HFNC initiation. Early intubation may lead to better survival in patients with 2-h mROX index < 4.45.
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COVID-19 , Cânula , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Taxa Respiratória , COVID-19/terapia , Oxigenoterapia , Intubação IntratraquealRESUMO
BACKGROUND: Nitrogen fertiliser is the major input and cost for wheat production, being required to support the development of the canopy to maximise yield and for the synthesis of the gluten proteins that are necessary for breadmaking. Consequently, current high-yielding cultivars require the use of nitrogen fertilisation levels above the yield optimum to achieve the grain protein content needed for breadmaking. This study aimed to reduce this requirement by identifying traits that allow the use of lower levels of nitrogen fertiliser to produce wheat for breadmaking. RESULTS: A range of commercial wheat genotypes (cultivars) were grown in multiple field trials (six sites over 3 years) in the UK with optimal (200 kg Ha-1 ) and suboptimal (150 kg Ha-1 ) application of nitrogen. Bulked grain samples from four sites per year were milled and white flours were baked using three types of breadmaking process. This identified five cultivars that consistently exhibited good breadmaking quality when grown with the lower nitrogen application. Chemical and biochemical analyses showed that the five cultivars were characterised by exhibiting grain protein deviation (GPD) and high dough elasticity. CONCLUSIONS: It is possible to develop novel types of wheat that exhibit good breadmaking quality by selecting for GPD and high dough strength. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Proteínas de Grãos , Triticum/química , Nitrogênio/metabolismo , Fertilizantes , Pão/análise , FertilizaçãoRESUMO
BACKGROUND: In view of the critical role of autophagy-related genes (ARGs) in the pathogenesis of various diseases including cancer, this study aims to identify and evaluate the potential value of ARGs in head and neck squamous cell carcinoma (HNSCC). METHODS: RNA sequencing and clinical data in The Cancer Genome Atlas (TCGA) were analyzed by univariate Cox regression analysis and Lasso Cox regression analysis model established a novel 13- autophagy related prognostic genes, which were used to build a prognostic risk model. A multivariate Cox proportional regression model and the survival analysis were used to evaluate the prognostic risk model. Moreover, the efficiency of prognostic risk model was tested by receiver operating characteristic (ROC) curve analysis based on data from TCGA database and Gene Expression Omnibus (GEO). Besides, the other independent datasets from Human Protein Atlas dataset (HPA) also applied. RESULTS: 13 ARGs (GABARAPL1, ITGA3, USP10, ST13, MAPK9, PRKN, FADD, IKBKB, ITPR1, TP73, MAP2K7, CDKN2A, and EEF2K) with prognostic value were identified in HNSCC patients. Subsequently, a prognostic risk model was established based on 13 ARGs, and significantly stratified HNSCC patients into high- and low-risk groups in terms of overall survival (OS) (HR = 0.379ï¼95% CI: 0.289-0.495, p < 0.0001). The multivariate Cox analysis revealed that this model was an independent prognostic factor (HR = 1.506, 95% CI = 1.330-1.706, P < 0.001). The areas under the ROC curves (AUC) were significant for both the TCGA and GEO, with AUC of 0.685 and 0.928 respectively. Functional annotation revealed that model significantly enriched in many critical pathways correlated with tumorigenesis, including the p53 pathway, IL2 STAT5 signaling, TGF beta signaling, PI3K Ak mTOR signaling by gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA). In addition, we developed a nomogram shown some clinical net could be used as a reference for clinical decision-making. CONCLUSIONS: Collectively, we developed and validated a novel robust 13-gene signatures for HNSCC prognosis prediction. The 13 ARGs could serve as an independent and reliable prognostic biomarkers and therapeutic targets for the HNSCC patients.
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Autofagia/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/genética , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/normas , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Biologia Computacional , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Redes e Vias Metabólicas/genética , Farmacologia em Rede , PrognósticoRESUMO
The wound-healing process is a natural response to burn injury. Resveratrol (RES) may have potential as a therapy for wound healing, but how and whether RES regulates skin repair remains poorly understood. Human epidermal keratinocyte (HaCaT) cells were treated with lipopolysaccharide (LPS), and a mouse skin wound-healing model was established. Cell viability and apoptosis were analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide or flow cytometry. Cell proliferation was assessed by cell viability and colony-formation analyses. Cell migration was tested by wound-healing analysis. The microRNA-212 (miR-212) and caspase-8 (CASP8) levels were determined by quantitative reverse transcription polymerase chain reaction and western blotting. The correlation between miR-212 and CASP8 was analyzed by dual-luciferase reporter analysis. Skin wound healing in mice was assessed by measuring the wound area and gap after hematoxylin-eosin (HE) staining. RES reduced the LPS-induced reduction in viability and apoptosis in HaCaT cells. miR-212 expression was reduced by LPS and increased by exposure to RES. RES promoted cell proliferation and migration after LPS treatment by increasing miR-212 levels. CASP8 was a target of miR-212. CASP8 silencing promoted cell proliferation and migration, which was reversed by miR-212 knockdown in LPS-treated HaCaT cells. RES promoted skin wound healing in mice, which was reduced by miR-212 knockdown. Thus, RES facilitates cell proliferation and migration in LPS-treated HaCaT cells and promotes skin wound-healing in a mouse model by regulating the miR-212/CASP8 axis.
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Caspase 8/metabolismo , MicroRNAs/metabolismo , Resveratrol/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The design and development of self-calibrating ratiometric luminescent sensors for the fast, accurate, and sensitive discrimination and determination of pollutants in wastewater is highly desirable for public and environmental health. Herein, a 3D porous Tb(III)-based metal-organic framework (MOF), {[Tb(HL)(H2O)2]·x(solv)}n (1), was facilely synthesized using a urea-functionalized tetracarboxylate ligand, 5,5'-(((1,4-phenylenebis(azanediyl))bis(carbonyl))bis(azanediyl))diisophthalic acid (H4L). The activated framework showed a good water stability in both aqueous solutions at a wide pH range of 2-14 and simulated antibiotic wastewaters. Interestingly, this Tb-MOF exhibited dual luminescence owing to the partial energy transfer from the antenna H4L to Tb3+. More importantly, activated 1 (1a) that was dispersed in water showed a fast, accurate, and highly sensitive discrimination ability toward antibiotics with a good recyclability, discriminating three different classes of antibiotics from each other via the quenching or enhancement of the luminescence and tuning the emission intensity ratio between the H4L ligand and the Tb3+ center for the first time. Simultaneously, 1a is a ratiometric luminescent sensor for the rapid, accurate, and quantitative discrimination of D2O from H2O. Furthermore, this complex was successfully used for the effective determination of antibiotics and D2O in real water samples. This work indicates that 1a represents the first ever MOF material for the discriminative sensing of antibiotics and D2O in H2O and promotes the practical application of Ln-MOF-based ratiometric luminescent sensors in monitoring water quality and avoiding any major leak situation.
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Antibacterianos/análise , Óxido de Deutério/química , Substâncias Luminescentes/química , Térbio/química , Antibacterianos/química , Limite de Detecção , Estruturas Metalorgânicas/química , Porosidade , Fatores de TempoRESUMO
The interfacial charge transfer from the substrate may influence the electronic structure of the epitaxial van der Waals (vdW) monolayers and, thus, their further technological applications. For instance, the freestanding Sb monolayer in the puckered honeycomb phase (α-antimonene), the structural analogue of black phosphorene, was predicted to be a semiconductor, but the epitaxial one behaves as a gapless semimetal when grown on the Td-WTe2 substrate. Here, we demonstrate that interface engineering can be applied to tune the interfacial charge transfer and, thus, the electron band of the epitaxial monolayer. As a result, the nearly freestanding (semiconducting) α-antimonene monolayer with a band gap of â¼170 meV was successfully obtained on the SnSe substrate. Furthermore, a semiconductor-semimetal crossover is observed in the bilayer α-antimonene. This study paves the way toward modifying the electron structure in two-dimensional vdW materials through interface engineering.
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OBJECTIVE: The aim of the study is to evaluate the optimal timing of sentinel lymph node biopsy (SLNB) in patients with clinical negative axillary lymph nodes (ALNs) before neoadjuvant therapy (NAT) and the feasibility of SLNB substituting for ALN dissection in patients with positive ALNs who convert to node negative, for HER2-positive disease. METHODS: Patients receiving SLNB with dual tracer mapping in the PEONY trial were analyzed. RESULTS: For 80 patients with clinical negative ALNs, the node negative rate by pathology after NAT was 83.8%. SLNB was performed after NAT in 71 patients. The identification rate of sentinel lymph nodes (SLNs) was 100%. For patients with positive ALNs before NAT, the axillary pathologic complete response rate in the dual HER2 blockade arm was significantly higher than that in the single blockade arm (p = 0.002). SLNB was performed in 71 patients. The identification rate was 100% and the false-negative rate was 17.2%. The false-negative rates were 33.3%, 14.3%, and 0 when 1, 2, and more than 2 SLNs were detected. There was no false-negative case when more than 1 SLN and the clipped nodes were removed simultaneously. CONCLUSIONS: For clinical ALN negative patients, HER2-positive subtype is found to have high node negative rate by pathology and it is recommended to undergo SLNB after NAT. For patients with positive ALNs who convert to negative, the false-negative rate is high. Dual tracer mapping, more than 2 SLNs detected, more than 1 SLN identified plus the clips placed are the guarantees for lower false-negative rate.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante/métodos , Receptor ErbB-2/metabolismo , Biópsia de Linfonodo Sentinela/métodos , Adulto , Idoso , Axila , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Método Duplo-Cego , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Resultado do Tratamento , Adulto JovemRESUMO
Until now, comparative studies on proton conductivity between organic ligands and related metal-organic frameworks (MOFs) have been very limited. Herein, a stable 2D Zn(II) MOF, [Zn(L)Cl]n (1), has been successfully synthesized by using a zwitterionic-type organic ligand, 2-(1-(carboxymethyl)-1H-benzo[d]imidazol-3-ium-3-yl)acetate (HL). It is found that there are a large amount of free carboxyl groups and hydrogen bonds in the solid-state structure of HL, and a large number of chlorine ions are aligned in the channels of 1, which is favorable to the efficient proton transfer. Correspondingly, the proton conductivity values of 1 and HL are almost of the same order of magnitude under the same conditions. Moreover, the optimal σ value of 1 (4.72 × 10-3 S/cm at 100 °C and 98% relative humidity) is almost four times higher than that (1.36 × 10-3 S/cm) of the HL ligand. On the basis of the crystal data, SEM images, and calculated Ea values, we discuss the differences on proton conductivities and conduction mechanisms of 1 and HL. This report provides an inspiration for the preparation of highly conductive materials with free carboxyl groups and chloride ions.
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BACKGROUND: Parkinson's disease (PD) is a progressive neurodegenerative movement disorder that is characterized by motor symptoms such as tremor, rigidity, slowness of movement and problems with gait. Large-scale meta-analyses of genome-wide association studies (GWAS) have identified few susceptibility loci in patients with sporadic PD. The aim of this study was to investigate the association between NMD3 single nucleotide polymorphism (SNP) and symptoms in PD patients in South China. METHODS: A total of 217 PD patients were recruited in this study and genotyped by using the SNaPshot technique and the polymerase chain reaction. All subjects were evaluated by the Mini-Mental State Examination (MMSE), Beijing version Montreal Cognitive Assessment (MoCA), Sniffin' Sticks 16 (SS-16), Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale, 39-item Parkinson's Disease Questionnaire (PDQ-39) and MDS Unified PD Rating Scale (MDS-UPDRS). RESULTS: NMD3 rs34016896 (C > T) carriers have worse cognitive function than wild types (MMSE: p = 0.042, NMD3 wild type: 27.44 ± 2.89, NMD3 carriers: 26.31 ± 3.79; MoCA: p = 0.005, NMD3 wild type: 23.15 ± 4.20, NMD3 carriers: 20.75 ± 6.68). CONCLUSIONS: The recessive and overdominant model of NMD3 rs34016896 was associated with cognitive impairment in PD patients.
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Disfunção Cognitiva/etiologia , Doença de Parkinson/complicações , Doença de Parkinson/genética , Proteínas de Ligação a RNA/genética , Idoso , Povo Asiático/genética , China , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Herein, the feasibility of Fe substitution by Ga, Ge and As in Li2FeSiO4 in modulating its structural, mechanical, electrochemical, capacity and electronic properties was systematically studied via first-principles calculations based on density functional theory within the generalized gradient approximation with Hubbard corrections (GGA+U). The calculated results show that Ga, Ge and As doping can effectively reduce the range of the cell volume change during Li+ removal, improving the Li+ detachment ability and cycle stability of the system. Meanwhile, the calculated mechanical properties including modulus ratio, B/G, and Poisson ratio, ν, indicate that the doped systems of Ga, Ge and As exhibit excellent mechanical properties. In addition, besides the increase in theoretical average deintercalation voltage induced by the Ga dopant when more than one Li+ ion is removed in the formula unit, the doping of Ga, Ge and As all reduce the theoretical average deintercalation voltage in the process of Li+ extraction. Especially in the case of doping of Ge, when 0.5 Li+ is removed from LiFe0.5Ge0.5SiO4, the theoretical average deintercalation voltage only increases by 0.19 V compared with the case of the removal of one Li+ in Li2Fe0.5Ge0.5SiO4, which causes the cathode material to have a longer and more stable discharge platform. Moreover, in the process of Li+ removal, the doping of Ga, Ge and As can effectively participate in the charge compensation of the system, and Ge and As can provide further charge, increasing the capacity of the Li2FeSiO4 cathode material considerably.
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Metal-organic frameworks (MOFs) have been extensively explored as advanced chemical sensors in recent years. However, there are few studies on MOFs as acidic gas sensors, especially proton conductive MOFs. In this work, two new proton-conducting 3D MOFs, {[Co3 (p-CPhHIDC)2 (4,4'-bipy)(H2 O)]â 2 H2 O}n (1) (p-CPhH4 IDC=2-(4-carboxylphenyl)-1 H-imidazole-4,5-dicarboxylic acid; 4,4'-bipy=4,4'-bipyridine) and {[Co3 (p-CPhHIDC)2 (bpe)(H2 O)]â 3 H2 O}n (2) (bpe=trans-1,2-bis(4-pyridyl)ethylene) have been solvothermally prepared and investigated their formic acid sensing properties. Both MOFs 1 and 2 show temperature- and humidity-dependent proton conductive properties and exhibit optimized proton conductivities of 1.04×10-3 and 7.02×10-4 â S cm at 98 % relative humidity (RH) and 100 °C, respectively. The large number of uncoordinated carboxylic acid sites, free and coordination water molecules, and hydrogen-bonding networks inside the frameworks are favorable to the proton transfer. By measuring the impedance values after exposure to formic acid vapor at 98 % or 68 % RH and 25 °C, both MOFs indicate reproducibly high sensitivity to the analyte. The detection limit of formic acid vapor is as low as 35â ppm for 1 and 70â ppm for 2. Meanwhile, both MOFs also show commendable selectivity towards formic acid among interfering solutions. The proton conducting and formic acid sensing mechanisms have been suggested according to the structural analysis, Ea calculations, N2 and water vapor absorptions, PXRD and SEM measurements. This work will open a new avenue for proton-conductive MOF-based impedance sensors and promote the potential application of these MOFs for indirectly monitoring the concentrations of formic acid vapors.
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This study aimed to explore the optimal time of sentinel lymph node biopsy (SLNB) and neo-adjuvant chemotherapy (NAC) and to assess the feasibility of selective elimination of axillary surgery after NAC in clinically node-negative (cN0) patients. From April 2010 to August 2018, 845 patients undergoing surgery after NAC were included in this retrospective study to analyze the correlation between different clinicopathological characteristics of cN0 patients and negative axillary lymph node after NAC (ypN0). Among the 148 cN0 patients, 83.1% (123/148) were ypN0. The rates of ypN0 in patients with hormone receptor positive (HR+)/HER2-, HR+/HER2+, HR-/HER2+, and triple-negative (TN) breast cancer were 75.4% (46/61), 82.6% (19/23), 85.2% (23/27), and 94.6% (35/37), respectively (P < 0.001). The rates of ypN0 in TN and HER2+ patients were 94.6% and 95.5%, which were significantly higher than that in HR+/HER2- patients (P < 0.05). Molecular subtypes, clinical stage, radiologic complete response, and pathologic complete response (bpCR) of the breast tumor correlated with ypN0 after full-course NAC (P < 0.05). Molecular subtypes (OR = 2.374, P = 0.033), clinical stage (OR = 0.320, P = 0.029), and bpCR (OR = 0.454, P = 0.012) were independent predictors for ypN0. The optimal time of SLNB and NAC in cN0 patients might be different among different molecular subtypes: it would be preferable to perform SLNB prior to NAC for HR+/HER2- patients, and SLNB after NAC for TN and HER2+ patients to reduce the risk of axillary lymph node dissection. In view of the high ypN0 rate in cN0 patients, axillary surgical staging might be selectively eliminated, especially for HER2+ and TN patients.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Axila/diagnóstico por imagem , Axila/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante/métodos , Feminino , Humanos , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Pessoa de Meia-Idade , Cintilografia , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela/efeitos adversos , Biópsia de Linfonodo Sentinela/métodosRESUMO
A novel perylene diimide (PDI) functionalized CeO2 nanocomposite (NC) was successfully fabricated via one-pot hydrothermal method. Compared with pure CeO2 nanoparticles (CeO2 NPs), the NC catalyst presents more Ce3+ and active oxygen species and exhibits a higher peroxidase mimicking activity towards the oxidation 3,3',5,5'-tetramethylbenzidine by H2O2 to form a blue product with an absorption maximum at 652 nm. The composite catalyst shows high sensitivity and selectivity toward H2O2 determination in the range of 20 to 80 µM with a limit of detection (LOD) of 2.59 µM. Based on the colorimetric method, a sensitive method for detecting the reduced glutathione (GSH) was also established over arrange of 1~4 µM with a LOD of 0.92 µM. Electron spin resonance (ESR) experiments suggest that the active radicals during the catalytic processes are â¢OH and â¢O2-. A possible synergistic catalytic mechanism is discussed. Graphical abstract Schematic presentation of the possible catalytic mechanism for colorimetric determination of hydrogen peroxide and glutathione based on the peroxidase-like activity perylene-diimide (PDI) functionalized CeO2 nanocomposite.
Assuntos
Materiais Biomiméticos/química , Cério/química , Glutationa/análise , Peróxido de Hidrogênio/análise , Imidas/química , Nanocompostos/química , Perileno/análogos & derivados , Benzidinas/química , Catálise , Colorimetria/métodos , Corantes/química , Peróxido de Hidrogênio/química , Indicadores e Reagentes/química , Limite de Detecção , Modelos Químicos , Oxirredução , Peroxidase/química , Perileno/químicaRESUMO
OBJECTIVES: This study was aimed to access the frequency and identify independent risk factors of refeeding intolerance in patients with mild acute interstitial pancreatitis. MATERIALS AND METHODS: Patients with mild acute pancreatitis (AP) were included in this observational, descriptive, and retrospective study. Clinical variables, therapy-related variables, and biochemical and radiological variables were analyzed by univariate and multivariate analysis. RESULTS: Of 323 included cases, 40 patients (12.4%) developed refeeding intolerance. In the final regression model, hypertriglyceridemia-induced AP (odds ratio, 7.72; 95% CI: 2.50-23.82, P < 0.001), elevated serum lipase (>2-fold of the upper limit of normal) before refeeding (odds ratio, 2.13; 95% CI: 1.2-3.77, P = 0.009), and immediate feeding (odds ratio, 1.75; 95% CI: 1.31-2.33, P < 0.001) were critical risk factors of refeeding intolerance. CONCLUSION: Refeeding intolerance occurs in 12.4% patients with mild AP and appears more often in those with hypertriglyceridemia-induced AP, elevated serum lipase (>2-fold of the upper limit of normal) before refeeding, and immediate feeding.
Assuntos
Apoio Nutricional/efeitos adversos , Pancreatite/complicações , Pancreatite/terapia , Doença Aguda , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Hipertrigliceridemia/complicações , Lipase/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Dor/etiologia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fumar/efeitos adversosRESUMO
Sea level fall is considered one of the significant factors leading to the end-Permian mass extinction (EPME). We studied the relative sea level changes in the Beifengjing and Shangsi sections, and the results indicate that a sea level fall occurred in the Upper Yangtze region during the Permian-Triassic transition. Considering that there is no significant change in fossil abundance in the strata following the two sea level falls observed in the Beifengjing section, we conclude that the reduction in shallow marine habitat for sea level fall solely was insufficient to cause the mass extinction. However, sea level fall did exacerbate the input of terrestrial debris into the ocean, leading to the deterioration of the marine environment. We propose that the combined adverse effects of volcanic eruptions, sea level falls, and other events exceeded the threshold for biological survival, ultimately resulting in the catastrophic EPME.