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1.
Chemosphere ; 358: 142186, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38701860

RESUMO

Fluorinated compounds (FCs) such as sulfur hexafluoride (SF6) and nitrogen trifluoride (NF3) have garnered attention due to their environmental impact. This study investigates the mineralization and removal of two potent FCs: SF6 and NF3. The results confirm that utilizing various oxalate salts leads to the formation of corresponding metallic fluorides: lithium fluoride (LiF), sodium fluoride (NaF), and potassium fluoride (KF), validating the occurrence of mineralization reactions. Among the oxalate salts, sodium oxalate demonstrates the highest mineralization efficiency in both SF6 and NF3 removal. Real-time Fourier transform infrared spectroscopy (FT-IR) gas-phase analysis confirms rapid and complete gas removal within a short reaction time using the selected oxalate salts. Meticulous mass balance calculations revealed that oxalates (LiF, NaF, and KF) yielded sulfur (S) at rates of 92.09%, 91.85%, and 84.98% following SF6 mineralization. Additionally, the conversion rates of oxalates to the corresponding metallic fluorides (LiF, NaF, and KF) after SF6 mineralization were 98.18%, 95.82%, and 95.21%, respectively. Similarly, after NF3 mineralization, these conversion rates stood at 92.18%, 90.67%, and 90.02%, respectively. The removal efficiencies for SF6 (1000 ppm) were 4.98, 12.01, and 7.23 L/g, while those for NF3 (1000 ppm) were 14.1, 12.6, and 11.7 L/g, respectively. Notably, sodium oxalate exhibits superior effectiveness, achieving 100% SF6 conversion within 30 min and 100% NF3 conversion within 50 min. This work underscores the potential of oxalate mineralization as a promising strategy for efficient and rapid removal of potent fluorinated compounds, paving the way for environmentally benign FC remediation techniques with broader implications for sustainable gas treatment technologies.

2.
Materials (Basel) ; 17(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38730891

RESUMO

The simultaneous increase in strength and plasticity of aluminum and its alloys at cryogenic temperatures has been shown in previous research, but the deformation mechanism was still unclear. Therefore, the purpose of this investigation was to reveal the relationship between slip behavior and mechanical response at low temperatures. A quasi-in situ scanning electron microscope was used to observe the evolution of slip bands in the selected aluminum single crystals with two typical orientations at 25 °C, -100 °C, and -180 °C. The results showed that irrespective of orientation, the density of the slip plane was increased with the decline in temperature, which inhibited slip localization and significantly improved plasticity and work hardening. In detail, at RT, the slip bands were widening until the micro-cracks were generated, causing early failure during deformation. When the temperature was decreased to -180 °C, the slip plane density was increased, and the deformation was more homogenous. Moreover, the slip mode was influenced by orientation and temperature. In particular, a single slip system was activated in the sample with the [112] orientation at all the temperatures investigated. Multiple slip systems were found to activate at 25 °C and -100 °C, and only the primary slip system was activated in the sample with [114] orientation at -180 °C. These findings deepen the understanding of slip behavior at cryogenic temperatures, providing new insights into the deformation mechanism of aluminum and its alloys.

3.
Zhen Ci Yan Jiu ; 49(4): 358-366, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38649203

RESUMO

OBJECTIVES: To analyze the effects of electroacupuncture (EA) at "Fenglong" (ST40) and "Zusanli" (ST36) of different intensities and durations on rats with non-alcoholic fatty liver disease (NAFLD) based on the protein kinase R-like endoplasmic reticulum kinase (PERK)-activating transcription factor 4 (ATF4)-C/EBP homologous protein (CHOP) signaling pathway, so as to explore its mechanism underlying improvement of NAFLD. METHODS: SD rats were randomly divided into normal diet group, high-fat model group, sham EA group, strong stimulation EA (SEA) group, and weak stimulation EA (WEA) group, with 15 rats in each group. Each group was further divided into 2, 3, and 4-week subgroups. NAFLD rat model was established by feeding a high-fat diet. After successful modeling, rats in the SEA and WEA groups received EA at bilateral ST40 and ST36 with dense and sparse waves (4 Hz/20 Hz) at current intensities of 4 mA (SEA group) and 2 mA (WEA group), lasting for 20 minutes, once a day, 5 days a week with 2 days of rest. The sham EA group only had the EA apparatus connected without electricity. Different duration subgroups were intervened for 2, 3, and 4 weeks. After the intervention, the contents of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in rats were detected by an automatic biochemical analyzer;liver morphological changes were observed by Oil Red O staining;real-time fluorescence quantitative PCR and Western blot were used to detect the expression of PERK, ATF4, and CHOP mRNAs and proteins in the rat liver tissue. RESULTS: In the high-fat model group, there was a significant accumulation of red lipid droplets in the liver cells, which was reduced significantly in the SEA group at the 4th week. Compared with the normal diet group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and proteins in the liver tissue were elevated (P<0.01) in the high-fat model group . Compared with the high-fat model group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, CHOP mRNAs and proteins in the liver tissue were decreased (P<0.01, P<0.05) in the SEA and WEA groups. Compared with the sham EA group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs were decreased (P<0.01, P<0.05) in the SEA and WEA groups, the expression of PERK, ATF4, and CHOP proteins in the liver tissue was decreased (P<0.01) in the SEA group at the 2nd, 3rd, and 4th week, the expression of PERK and CHOP proteins at the 2nd, 3rd, 4th week and ATF4 protein at 2nd week in the liver tissue were decreased (P<0.01, P<0.05) in the WEA group. Compared with the SEA group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and proteins in the liver tissue were elevated (P<0.05, P<0.01) in the WEA group. Compared with the 2-week time point within the groups, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and PERK proteins in the liver tissue were decreased (P<0.01, P<0.05) in the SEA and WEA groups at 3rd and 4th week, the expression of ATF4 proteins in the liver tissue was decreased (P<0.01) in the SEA group at 3rd and 4th week, and the expression of CHOP proteins in the liver tissue was decreased (P<0.01) in the SEA group at 4th week and in the WEA group at 3rd and 4th week. Compared with the 3-week time point within the groups, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs were significantly decreased (P<0.05, P<0.01) in the SEA and WEA groups at 4th week, the expression of PERK and CHOP proteins in the liver tissue was decreased (P<0.01) in the SEA and WEA groups at 4th week, and the expression of ATF4 protein in the liver tissue was decreased (P<0.05) in the SEA group at 4th week. CONCLUSIONS: EA at ST40 and ST36 can significantly improve liver function in NAFLD rats, and its mechanism of action may involve inhibiting PERK expression thereby targeting the downstream ATF4/CHOP signaling pathway to suppress endoplasmic reticulum stress, exerting a liver protective effect;the optimal effect was observed with EA intensity of 4 mA for 4 weeks.


Assuntos
Fator 4 Ativador da Transcrição , Pontos de Acupuntura , Eletroacupuntura , Fígado , Hepatopatia Gordurosa não Alcoólica , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Transcrição CHOP , eIF-2 Quinase , Animais , Ratos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Hepatopatia Gordurosa não Alcoólica/genética , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição CHOP/genética
4.
World J Diabetes ; 15(4): 586-590, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38680688

RESUMO

Obesity is a prevalent cause of diabetes mellitus (DM) and is a serious danger to human health. Type 2 DM (T2DM) mostly occurs along with obesity. Foodborne obesity-induced DM is caused by an excessive long-term diet and surplus energy. Bariatric surgery can improve the symptoms of T2DM in some obese patients. But different types of bariatric surgery may have different effects. There are some models built by researchers to discuss the surgical procedures' effects on metabolism in diabetes animal models and diabetes patients. It is high time to conclude all this effects and recommend procedures that can better improve metabolism.

5.
Biomater Adv ; 160: 213857, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657287

RESUMO

Articular cartilage injury impairs joint function and necessitates orthopedic intervention to restore the structure and function of the cartilage. Extracellular matrix (ECM) scaffolds derived from bone marrow mesenchymal stem cells (BMSCs) can effectively promote cell adhesion, proliferation, and chondrogenesis. However, pre-shaped ECM scaffolds have limited applicability due to their poor fit with the irregular surface of most articular cartilage defects. In this study, we fabricated an injectable active ECM hydrogel from autologous BMSCs-derived ECM by freeze-drying, liquid nitrogen milling, and enzymatic digestion. Moreover, our in vitro and in vivo results demonstrated that the prepared hydrogel enhanced chondrocyte adhesion and proliferation, chondrogenesis, cartilage regeneration, and integration with host tissue, respectively. These findings indicate that active ECM components can provide trophic support for cell proliferation and differentiation, restoring the structure and function of damaged cartilage.


Assuntos
Cartilagem Articular , Condrócitos , Condrogênese , Matriz Extracelular , Hidrogéis , Células-Tronco Mesenquimais , Regeneração , Engenharia Tecidual , Alicerces Teciduais , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Animais , Células-Tronco Mesenquimais/citologia , Cartilagem Articular/fisiologia , Cartilagem Articular/lesões , Hidrogéis/química , Alicerces Teciduais/química , Condrócitos/transplante , Engenharia Tecidual/métodos , Proliferação de Células , Diferenciação Celular , Coelhos , Adesão Celular , Humanos , Injeções
6.
ACS Sens ; 9(4): 2183-2193, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38588327

RESUMO

Sensitive and selective acetone detection is of great significance in the fields of environmental protection, industrial production, and individual health monitoring from exhaled breath. To achieve this goal, bimetallic Au@Pt core-shell nanospheres (BNSs) functionalized-electrospun ZnFe2O4 nanofibers (ZFO NFs) are prepared in this work. Compared to pure NFs-650 analogue, the ZFO NFs/BNSs-2 sensor exhibits a stronger mean response (3.32 vs 1.84), quicker response/recovery speeds (33 s/28 s vs 54 s/42 s), and lower operating temperature (188 vs 273 °C) toward 0.5 ppm acetone. Note that an experimental detection limit of 30 ppb is achieved, which ranks among the best cases reported thus far. Besides the demonstrated excellent repeatability, humidity-enhanced response, and long-term stability, the selectivity toward acetone is remarkably improved after BNSs functionalization. Through material characterizations and DFT calculations, all these improvements could be attributed to the boosted oxygen vacancies and abundant Schottky junctions between ZFO NFs and BNSs, and the synergistic catalytic effect of BNSs. This work offers an alternative strategy to realize selective subppm acetone under high-humidity conditions catering for the future requirements of noninvasive breath diabetes diagnosis in the field of individual healthcare.


Assuntos
Acetona , Testes Respiratórios , Ouro , Nanofibras , Nanosferas , Platina , Acetona/análise , Acetona/química , Nanofibras/química , Ouro/química , Testes Respiratórios/métodos , Nanosferas/química , Platina/química , Humanos , Limite de Detecção , Oxigênio/química , Técnicas Eletroquímicas/métodos
7.
Sci Adv ; 10(17): eadl1455, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669337

RESUMO

Nanosheet-based membranes have shown enormous potential for energy-efficient molecular transport and separation applications, but designing these membranes for specific separations remains a great challenge due to the lack of good understanding of fluid transport mechanisms in complex nanochannels. We synthesized reduced MXene/graphene hetero-channel membranes with sub-1-nm pores for experimental measurements and theoretical modeling of their structures and fluid transport rates. Our experiments showed that upon complete rejection of salt and organic dyes, these membranes with subnanometer channels exhibit remarkably high solvent fluxes, and their solvent transport behavior is very different from their homo-structured counterparts. We proposed a subcontinuum flow model that enables accurate prediction of solvent flux in sub-1-nm slit-pore membranes by building a direct relationship between the solvent molecule-channel wall interaction and flux from the confined physical properties of a liquid and the structural parameters of the membranes. This work provides a basis for the rational design of nanosheet-based membranes for advanced separation and emerging nanofluidics.

8.
Appl Opt ; 63(8): 1982-1990, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568638

RESUMO

Currently, the method of establishing the correspondence between the flame light field image and the temperature field by deep learning is widely used. Based on convolutional neural networks (CNNs), the reconstruction accuracy has been improved by increasing the depth of the network. However, as the depth of the network increases, it will lead to gradient explosion and network degradation. To further improve the reconstruction accuracy of the flame temperature field, this paper proposes an ES-ResNet18 model, in which SoftPool is used instead of MaxPool to preserve feature information more completely and efficient channel attention (ECA) is introduced in the residual block to reassign more weights to feature maps of critical channels. The reconstruction results of our method were compared with the CNN model and the original ResNet18 network. The results show that the average relative error and the maximum relative error of the temperature field reconstructed by the ES-ResNet18 model are 0.0203% and 0.1805%, respectively, which are reduced by one order of magnitude compared to the CNN model. Compared to the original ResNet18 network, they have decreased by 17.1% and 43.1%, respectively. Adding Gaussian noise to the flame light field images, when the standard deviation exceeds 0.03, the increase in reconstruction error of the ES-ResNet18 model is lower than that of ResNet18, demonstrating stronger anti-noise performance.

9.
Pancreatology ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38565467

RESUMO

BACKGROUND/OBJECTIVES: Liposomal irinotecan plus 5-fluorouracil and leucovorin (nal-IRI + 5-FU/LV) provides survival benefits for metastatic pancreatic adenocarcinoma (mPDAC) refractory to gemcitabine-based treatment, mainly gemcitabine plus nab-paclitaxel (GA), in current practice. Gemcitabine plus S-1 (GS) is another commonly administered first-line regimen before nab-paclitaxel reimbursement; however, the efficacy and safety of nal-IRI + 5-FU/LV for mPDAC after failed GS treatment has not been reported and was therefore explored in this study. METHODS: In total, 177 patients with mPDAC received first-line GS or GA treatment, followed by second-line nal-IRI + 5-FU/LV treatment (identified from a multicenter retrospective cohort in Taiwan from 2018 to 2020); 85 and 92 patients were allocated to the GS and GA groups, respectively. Overall survival (OS), time-to-treatment failure (TTF), and adverse events were compared between the two groups. RESULTS: The baseline characteristics of the two groups were generally similar; however, a higher median age (67 versus 62 years, p < 0.001) and fewer liver metastases (52% versus 78%, p < 0.001) were observed in the GS versus GA group. The median OS was 15.0 and 15.9 months in the GS and GA groups, respectively (p = 0.58). The TTF (3.1 versus 2.8 months, p = 0.36) and OS (7.6 versus 6.7 months, p = 0.83) after nal-IRI treatment were similar between the two groups. More patients in the GS group developed mucositis during nal-IRI treatment (15% versus 4%, p = 0.02). CONCLUSIONS: The efficacy of second-line nal-IRI +5-FU/LV treatment was unaffected by prior S-1 exposure. GS followed by nal-IRI treatment is an alternative treatment sequence for patients with mPDAC.

10.
Med Sci Monit ; 30: e943738, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664941

RESUMO

BACKGROUND The pathological mechanism of osteoarthritis is still unclear. The regulation of the immune microenvironment has been of growing interest in the progression and treatment of osteoarthritis. Macrophages with different phenotypes, producing different cytokines, have been linked to the mechanism of cartilage injury in osteoarthritis. Copper ions play a role in the immune response and are involved in the pathological mechanisms of osteoarthritis by affecting the metabolism of the cartilage matrix. Bioactive glass (BG) is an osteogenic material with superior biocompatibility. Here, we report on the regulatory behavior of macrophages using a copper-based composite BG material. MATERIAL AND METHODS Cu-BGC powder was prepared by sol-gel method, and scaffolds were fabricated and characterized using 3D printing. Macrophage cultures grown with Cu-BGC were examined for cell culture and proliferation. The effect of Cu-BGC on the degradation metabolism of chondrocytes, cultured in the environment of inflammatory cytokine IL-1ß, was determined. In addition, the morphology of macrophages, secretion of inflammatory cytokines, and expression of surface markers were examined. RESULTS The results show that Cu-BGC promotes macrophage proliferation at a range of concentrations and increases the secretion of anti-inflammatory cytokines while inhibiting proinflammatory cytokines. At the same time, M2-type cell surface markers are definitely expressed and the morphology of macrophages is altered. In addition, Cu-BGC inhibited the degradation metabolism of chondrocytes in the inflammatory environment induced by IL-1ß. CONCLUSIONS These results suggest that Cu-BGC induced macrophage polarization into an M2 type anti-inflammatory phenotype, and inhibition of immune injury response may play a role in delaying cartilage matrix damage in osteoarthritis.


Assuntos
Proliferação de Células , Condrócitos , Cobre , Citocinas , Macrófagos , Osteoartrite , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Osteoartrite/patologia , Osteoartrite/metabolismo , Animais , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Cobre/metabolismo , Cobre/farmacologia , Citocinas/metabolismo , Camundongos , Proliferação de Células/efeitos dos fármacos , Cartilagem Articular/patologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Cartilagem/metabolismo , Cartilagem/efeitos dos fármacos , Cartilagem/patologia , Células RAW 264.7 , Vidro , Alicerces Teciduais
11.
Nanoscale ; 16(17): 8345-8351, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38606457

RESUMO

2D WSe2-based electronic devices have received much research interest. However, it is still a challenge to achieve high electronic performance in WSe2-based devices. In this work, we report greatly enhanced performances of different thickness WSe2 ambipolar transistors and demonstrate homogeneous WSe2 inverter devices, which are obtained by using a semiconductor processing-compatible layer removal technique via chemical removal of the surface top WOx layer formed by O2 plasma treatment. Importantly, monolayer WSe2 was realised after several consecutive removal processes, demonstrating that the single layer removal is accurate and reliable. After subsequent removal of the top layer WOx by KOH, the fabricated WSe2 field-effect transistors exhibit greatly enhanced electronic performance along with the high electron and hole mobilities of 40 and 85 cm2 V-1 s-1, respectively. Our work demonstrates that the layer removal technique is an efficient route to fabricate high performance 2D material-based electronic devices.

12.
BMJ Open ; 14(3): e081022, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531569

RESUMO

INTRODUCTION: Non-pharmacological interventions play a crucial role in the management of non-specific chronic low back pain (NSCLBP). One prime example is Tuina, a traditional Chinese manual therapy that incorporates pressing, kneading and rubbing techniques to alleviate physical discomfort and enhance overall well-being. It serves as a widely used technique in China and other East Asian countries. However, the effectiveness and safety of Tuina for managing NSCLBP have not been substantiated through rigorous clinical research. We sought to carry out a randomised controlled trial with an open-label design, blinded assessors and parallel arms to assess the effectiveness and safety of Tuina as a treatment for NSCLBP. The trial aims to provide high-quality evidence regarding the efficacy and safety of Tuina in improving outcomes for patients with NSCLBP. METHODS AND ANALYSIS: A total of 150 patients aged 18-60 years with NSCLBP will be recruited. Participants will be randomly assigned to one of the two groups. Both groups will receive standard health education. In addition, the treatment group will receive Tuina therapy, while the control group will participate in core stability exercises. Each group will undergo a total of 18 interventions over 6 weeks, with the interventions administered three times per week. The primary outcome measure is the patient's pain intensity, assessed using the Numerical Rating Scale, at week 6 following randomisation. Secondary outcomes encompass disability (measured by the Roland-Morris Disability Questionnaire), quality of life (assessed using the EuroQoL-5 dimensions questionnaire), adverse emotions (evaluated with the Pain Catastrophizing Scale, Tampa Scale of Kinesiophobia and Depression Anxiety Stress Scale), biomechanical outcomes, socioeconomic indicators (medication use, healthcare utilisation and absenteeism), patient satisfaction, treatment adherence and other relevant factors.The statistical analysis will follow the intention-to-treat principle. Two-way repeated measures analysis of variance will be used to compare the clinical data across different time points within both groups. ETHICS AND DISSEMINATION: The study protocol has received approval from the Ethics Committee of Shuguang Hospital, Shanghai University of Traditional Chinese Medicine (2023-1366-133-01). All study participants will be required to give written informed consent. The findings of the study will be submitted to a peer-reviewed journal for publication and presented at scientific conferences. Additionally, the participants will receive copies of the results. TRIAL REGISTRATION NUMBER: ChiCTR2300076257.


Assuntos
Dor Crônica , Dor Lombar , Manipulações Musculoesqueléticas , Humanos , Dor Lombar/terapia , Qualidade de Vida , China , Projetos de Pesquisa , Dor Crônica/terapia , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Biosensors (Basel) ; 14(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38534260

RESUMO

An electrocardiogram (ECG) is used to observe the electrical activity of the heart via electrodes on the body surface. Recently, an ECG with fewer electrodes, such as a bipolar ECG in which two electrodes are attached to the chest, has been employed as wearable devices. However, the effect of different geometrical factors and electrode-pair locations on the amplitude and waveform of ECG signals remains unclear. In this study, we computationally evaluated the effects of body morphology, heart size and orientation, and electrode misalignment on ECG signals for 48 scenarios using 35 bipolar electrode pairs (1680 waveforms) with a dynamic time warping (DTW) algorithm. It was observed that the physique of the human body model predominantly affected the amplitude and waveform of the ECG signals. A multivariate analysis indicated that the heart-electrode distance and the solid angle of the heart from the electrode characterized the amplitude and waveform of the ECG signals, respectively. Furthermore, the electrode locations for less individual variability and less waveform distortion were close to the location of electrodes V2 and V3 in the standard 12-lead. These findings will facilitate the placement of ECG electrodes and interpretation of the measured ECG signals for wearable devices.


Assuntos
Eletrocardiografia , Dispositivos Eletrônicos Vestíveis , Humanos , Algoritmos , Eletrodos
14.
J Am Chem Soc ; 146(13): 9434-9443, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38507716

RESUMO

Electrocatalytic synthesis of hydrogen peroxide (H2O2) in acidic media is an efficient and eco-friendly approach to produce inherently stable H2O2, but limited by the lack of selective and stable catalysts under industrial-relevant current densities. Herein, we report a diatomic cobalt catalyst for two-electron oxygen reduction to efficiently produce H2O2 at 50-400 mA cm-2 in acid. Electrode kinetics study shows a >95% selectivity for two-electron oxygen reduction on the diatomic cobalt sites. In a flow cell device, a record-high production rate of 11.72 mol gcat-1 h-1 and exceptional long-term stability (100 h) are realized under high current densities. In situ spectroscopic studies and theoretical calculations reveal that introducing a second metal into the coordination sphere of the cobalt site can optimize the binding strength of key H2O2 intermediates due to the downshifted d-band center of cobalt. We also demonstrate the feasibility of processing municipal plastic wastes through decentralized H2O2 production.

15.
Small ; : e2312229, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488721

RESUMO

δ-MnO2 is a promising cathode material for aqueous aluminium-ion batteries (AAIBs) for its layered crystalline structure with large interlayer spacing. However, the excellent Al ion storage performance of δ-MnO2 cathode remains elusive due to the frustrating structural collapse during the intercalation of high ionic potential Al ion species. Here, it is discovered that introducing heterogeneous metal dopants with high bond dissociation energy when bonded to oxygen can significantly reinforce the structural stability of δ-MnO2 frameworks. This reinforcement translates to stable cycling properties and high specific capacity in AAIBs. Vanadium-doped δ-MnO2 (V-δ-MnO2 ) can deliver a high specific capacity of 518 mAh g-1 at 200 mA g-1 with remarkable cycling stability for 400 cycles and improved rate capabilities (468, 339, and 285 mAh g-1 at 0.5, 1, and 2 A g-1 , respectively), outperforming other doped δ-MnO2 materials and the reported AAIB cathodes. Theoretical and experimental studies indicate that V doping can substantially improve the cohesive energy of δ-MnO2 lattices, enhance their interaction with Al ion species, and increase electrical conductivity, collectively contributing to high ion storage performance. These findings provide inspiration for the development of high-performance cathodes for battery applications.

16.
ACS Omega ; 9(9): 10583-10591, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463287

RESUMO

Activated carbon-supported CuO catalysts were prepared by an ammonia evaporation method and applied to catalyze the selective oxidation of glycerol to lactic acid. The effects of CuO loadings on the structure and catalytic performance of the catalyst were investigated. Results showed that CuO could be dispersed uniformly on the surface of activated carbon, promoting the increase of the reaction rate and accelerating the glycerol conversion significantly. As CuO loadings increased, the rate of glycerol consumption and yield to lactic acid was increased. However, too high CuO loadings would destroy the original pore structure of activated carbon and aggravate the agglomeration of CuO, resulting in a decrease in the catalytic performance of the catalyst. The best catalytic performance was obtained over 10% CuO/AC when the reaction temperature was 190 °C and the reaction time was 5 h. At this point, the selectivity to lactic acid reached 92.61%. In addition, power-function type reaction kinetic equations were used to evaluate the effect of glycerol and NaOH concentrations and the reaction temperature on the oxidation of glycerol to lactic acid over 10% CuO/AC. The activation energy of the reaction is 134.39 kJ·mol-1, which is higher than that using single CuO as the catalyst. This indicates that CuO/AC is more temperature-sensitive than CuO and can probably achieve a higher lactic acid yield at high temperatures. At the same time, it is indicated that CuO supported on activated carbon can enhance the catalytic activity of CuO effectively.

17.
Magn Reson Imaging ; 111: 28-34, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492786

RESUMO

OBJECTIVE: To investigate the feasibility and diagnostic efficacy of a 3D multiecho Dixon (qDixon) research application for simultaneously quantifying the liver iron concentration (LIC) and steatosis in thalassemia patients. MATERIALS AND METHODS: This prospective study enrolled participants with thalassemia who underwent 3 T MRI of the liver for the evaluation of hepatic iron overload. The imaging protocol including qDixon and conventional T2* mapping based on 2D multiecho gradient echo (ME GRE) sequences respectively. Regions of interest (ROIs) were drawn in the liver on the qDixon maps to obtain R2* and proton density fat fraction (PDFF). The reference R2* value was measured and calculated on conventional T2* mapping using the CMRtools software. Correlation analysis, Linear regression analysis, and Bland-Altman analysis were performed. RESULTS: 84 patients were finally included in this study. The median R2*-ME-GRE was 366.97 (1/s), range [206.68 (1/s), 522.20 (1/s)]. 8 patients had normal hepatic iron deposition, 16 had Insignificant, 42 had mild, 18 had moderate. The median of R2*-qDixon was 376.88 (1/s) [219.33 (1/s), 491.75 (1/s)]. A strong correlation was found between the liver R2*-qDixon and the R2*-ME-GRE (r = 0.959, P < 0.001). The median value of PDFF was 1.76% (1.10%, 2.95%). 8 patients had mild fatty liver, and 1 had severe fatty liver. CONCLUSION: MR qDixon research sequence can rapidly and accurately quantify liver iron overload, that highly consistent with the measured via conventional GRE sequence, and it can also simultaneously detect hepatic steatosis, this has great potential for clinical evaluation of thalassemia patients.

18.
World J Gastrointest Surg ; 16(1): 29-39, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38328311

RESUMO

BACKGROUND: Due to the prolonged life expectancy and increased risk of colorectal cancer (CRC) among patients with human immunodeficiency virus (HIV) infection, the prognosis and pathological features of CRC in HIV-positive patients require examination. AIM: To compare the differences in oncological features, surgical safety, and prognosis between patients with and without HIV infection who have CRC at the same tumor stage and site. METHODS: In this retrospective study, we collected data from HIV-positive and -negative patients who underwent radical resection for CRC. Using random stratified sampling, 24 HIV-positive and 363 HIV-negative patients with colorectal adenocarcinoma after radical resection were selected. Using propensity score matching, we selected 72 patients, matched 1:2 (HIV-positive:negative = 24:48). Differences in basic characteristics, HIV acquisition, perioperative serological indicators, surgical safety, oncological features, and long-term prognosis were compared between the two groups. RESULTS: Fewer patients with HIV infection underwent chemotherapy compared to patients without. HIV-positive patients had fewer preoperative and postoperative leukocytes, fewer preoperative lymphocytes, lower carcinoembryonic antigen levels, more intraoperative blood loss, more metastatic lymph nodes, higher node stage, higher tumor node metastasis stage, shorter overall survival, and shorter progression-free survival compared to patients who were HIV-negative. CONCLUSION: Compared with CRC patients who are HIV-negative, patients with HIV infection have more metastatic lymph nodes and worse long-term survival after surgery. Standard treatment options for HIV-positive patients with CRC should be explored.

19.
J Hazard Mater ; 468: 133803, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377910

RESUMO

Micro and nanosized plastics (MNPs), and a range of associated additive chemicals, have become pervasive contaminants that humans and the environment are exposed to everyday. However, one of the principal challenges in their analysis is adequate strategies to minimise background contamination. Here a blueprint for a specialised plastics and additive-minimised clean room laboratory built for this purpose is presented. Common laboratory construction materials (n = 23) were tested, including acoustic baffles, ceiling materials, floor materials, glazing rubber, and silicone sealant. The % polymer content ranged from 2-76% w/w while the sum concentration of six phthalates ranged from 0.81 (0.73-0.86) to 21000 (15000-27000) mg/kg, assigning many of these materials as inappropriate for use in a clean room environment. The final design of the laboratory consisted of three interconnected rooms, operated under positive pressure with the inner rooms constructed almost entirely of stainless steel. Background concentrations of MNPs and phthalates in the new laboratory were compared to two Physical Containment Level 2 (PC2) laboratory environments, with concentrations of MNPs reduced by > 100 times and phthalates reduced by up to 120 times. This study reports the first known clean room of its kind and provides a blueprint for reference and use by future plastics research.

20.
Curr Med Res Opin ; 40(4): 567-574, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38407177

RESUMO

OBJECTIVE: To evaluate the efficacy endpoints of HbA1c and body weight loss after switching from the GLP-1 receptor agonists, semaglutide or dulaglutide, to treatment with the GIP/GLP-1 receptor agonist (RA) tirzepatide. METHODS: Models were developed and validated to describe the HbA1c and weight loss time course for semaglutide (SUSTAIN 1-10), dulaglutide (AWARD-11) and tirzepatide (SURPASS 1-5, phase 3 global T2D program). The impact of switching from once weekly GLP-1 RAs to tirzepatide was described by simulating the efficacy time course. Semaglutide and dulaglutide doses were escalated in accordance with their respective labels. RESULTS: Model-predicted mean decreases from baseline in HbA1c and body weight for semaglutide 0.5 mg, 1 mg, and 2 mg were 1.22 to 1.79% and 3.62 to 6.87 kg respectively, at Week 26. Model-predicted mean decreases from baseline in HbA1c and body weight for dulaglutide 1.5 mg, 3 mg and 4.5 mg were 1.53 to 1.84% and 2.55 to 3.71 kg respectively, at Week 26. After switching to tirzepatide 5, 10 and 15 mg HbA1c reductions were predicted to range between 1.95 to 2.46% and body weight reductions between 6.50 to 12.1 kg by Week 66. CONCLUSION: In this model-based simulation, switching from approved maintenance doses of semaglutide or dulaglutide to tirzepatide, even at the lowest approved maintenance dose of 5 mg, showed the potential to further improve HbA1c and body weight reductions.


Type 2 diabetes is a disease of elevated blood sugar levels. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are a type of medication used to treat type 2 diabetes that work on GLP-1 receptors in the body. Semaglutide and dulaglutide are examples of GLP-1 RAs, which lower blood sugar and body weight. Tirzepatide is a newer medication, which works on both GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptors. It reduces blood sugar and body weight in people living with type 2 diabetes. Healthcare professionals and patients are interested in how switching medication from semaglutide or dulaglutide to tirzepatide might change blood glucose levels and body weight. However, because tirzepatide is a newer medication, there is not much information available on this aspect. Data from clinical trials of these medications were used to predict the effects of switching from semaglutide or dulaglutide to tirzepatide. These model-based simulations showed that switching to tirzepatide may further reduce HbA1c (a measure of blood sugar) and body weight. This may provide useful information to healthcare professionals and patients when making decisions about treatment with these medications.


Assuntos
Diabetes Mellitus Tipo 2 , Polipeptídeo Inibidor Gástrico , Receptor do Peptídeo Semelhante ao Glucagon 2 , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Humanos , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Peso Corporal , Redução de Peso , Peptídeo 1 Semelhante ao Glucagon , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas
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