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1.
J Neurosci Methods ; 409: 110217, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964477

RESUMO

BACKGROUND: Parkinson's patients have significant autonomic dysfunction, early detect the disorder is a major challenge. To assess the autonomic function in the rat model of rotenone induced Parkinson's disease (PD), Blood pressure and ECG signal acquisition are very important. NEW METHOD: We used telemetry to record the electrocardiogram and blood pressure signals from awake rats, with linear and nonlinear analysis techniques calculate the heart rate variability (HRV) and blood pressure variability (BPV). we applied nonlinear analysis methods like sample entropy and detrended fluctuation analysis to analyze blood pressure signals. Particularly, this is the first attempt to apply nonlinear analysis to the blood pressure evaluate in rotenone induced PD model rat. RESULTS: HRV in the time and frequency domains indicated sympathetic-parasympathetic imbalance in PD model rats. Linear BPV analysis didn't reflect changes in vascular function and blood pressure regulation in PD model rats. Nonlinear analysis revealed differences in BPV, with lower sample entropy results and increased detrended fluctuation analysis results in the PD group rats. COMPARISON WITH EXISTING METHODS AND CONCLUSIONS: our experiments demonstrate the ability to evaluate autonomic dysfunction in models of Parkinson's disease by combining the analysis of BPV with HRV, consistent with autonomic impairment in PD patients. Nonlinear analysis by blood pressure signal may help in early detection of the PD. It indicates that the fluctuation of blood pressure in the rats in the rotenone model group tends to be regular and predictable, contributes to understand the PD pathophysiological mechanisms and to find strategies for early diagnosis.

2.
Heliyon ; 10(11): e32113, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38867946

RESUMO

Introduction: Dysregulation in lipid metabolism contributes to the occurrence and development of various cancers. The connection between changes in lipid metabolism and the development of intrahepatic cholangiocarcinoma remains uncertain. Our objective was to investigate the significance of blood lipid levels in patients with intrahepatic cholangiocarcinoma who have undergone surgery. Methods: Ninety-seven ICC patients who underwent surgery were retrospectively enrolled. After 92.2 months of follow-up, the Kaplan-Meier analysis and Cox proportional hazard model were used to calculate overall survival and recurrence-free survival. Results: The median age of this cohort was 56 years, and 79 (81.4 %) of them were male. Eighty-eight (90.7 %) patients presented with tumor recurrence and 73 (75.3 %) died. In multivariate analyses, high-density lipoprotein cholesterol level (<0.91 vs. ≥ 0.91 mmol/L, hazard ratio [HR] = 2.55; 95 % CI: 1.38-4.71), lymph node metastasis (Yes vs. No, HR = 2.58; 95 % CI: 1.28-5.19), etiology factor (chronic HBV infection vs. others, HR = 0.5; 95 % CI: 0.28-0.88) and multiple tumor lesions (Yes vs. No, HR = 1.85; 95 % CI: 1.01-3.39) were independent predictors of overall survival. However, only high-density lipoprotein cholesterol level (HR = 1.86; 95 % CI: 1.19-2.92) emerged as the independent factor for recurrence-free survival. High-density lipoprotein cholesterol level (HR = 2.07; 95 % CI: 1.26-3.41), etiology factor (HR = 0.49; 95 % CI: 0.29-0.84), and multiple tumor lesions (HR = 2.00; 95 % CI: 1.14-3.51) were independent predictors of early recurrence. For patients who did not experience the spread of cancer to the lymph nodes, there was a significant correlation between the level of high-density lipoprotein cholesterol and their overall survival, recurrence-free survival, and early recurrence. For patients with low pre-operation high-density lipoprotein cholesterol levels, high post-operation high-density lipoprotein cholesterol levels were associated with better prognosis. Conclusions: Low serum high-density lipoprotein cholesterol level might serve as a sign of poor clinical outcomes (overall survival and recurrence-free survival) and early recurrence among intrahepatic cholangiocarcinoma patients. Strengthening the monitoring and intervention of intrahepatic cholangiocarcinoma patients with poor prognosis might be critical for improving the prognosis.

3.
Inorg Chem ; 63(21): 9706-9710, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38747511

RESUMO

Herein, we detail the synthesis, structure, and photoconductivity of the uranyl dithiophosphinate single crystal UO2[S2P(C6H5)2]2(CH3OH)·CH3OH (denoted as U-DPDPP). The formation of bonds between uranyl ions and sulfur-based ligands endows U-DPDPP with a distinct electronic absorption property with a broadband spectrum spanning from 250 to 550 nm, giving rise to a unique semiconductive property. Under X-ray illumination, U-DPDPP displays a distinctive photoconductivity response, with a charge carrier mobility lifetime (µτ) of 2.78 × 10-4 cm2·V-1 achieved, which contradicts the electronic-silence behavior of uranyl nitrate crystal.

4.
AIDS Care ; : 1-9, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648522

RESUMO

A worrying phenomenon has emerged recently: more people are deliberately avoiding rather than seeking information regarding acquired immunodeficiency syndrome (AIDS). This is the first study to explore behaviors related to AIDS information avoidance and the potential influential factors among older men who have sex with men (MSM). We enrolled 11 older MSM from Wuhan, the largest city in central China, from January to March 2023 using a phenomenological method. This qualitative research was conducted using face-to-face semi-structured interviews. AIDS information avoidance was commonly observed among the respondents. Behaviors related to AIDS information avoidance included avoiding AIDS-related information, ignoring known AIDS information, and avoiding medical care. The main factors associated with AIDS information avoidance included information overload, high-risk sexual behaviors, over-optimism, fear of disclosure, and age. China should provide AIDS information in a manner suitable for older MSM, pay more attention to MSM over the age of 70 years, those who are not open about their sexual orientation and those who are too optimistic, and strengthen the censorship of AIDS information.

5.
Pharmacol Res ; 203: 107142, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522759

RESUMO

ZLDI-8 is an A disintegrin and metalloproteinase domain 17 (ADAM17) inhibitor that suppresses the shedding of Notch1 to the Notch1 intracellular domain (NICD). In previous studies, we found that ZLDI-8 was able to sensitize HCC to sorafenib, but the mechanism of action remains unclear. The sensitizing effects of ZLDI-8 were tested both in vitro and in vivo. EMT-related factors, sorafenib sensitivity-related proteins and ECM-related gene expression were assessed using immunohistochemistry, RTPCR and Western blotting. Knockdown assays were conducted to determine the relationship between the Notch and Integrin pathways. CoIP assays, nuclear and cytoplasmic fractionation and immunofluorescence colocalization were applied to explore the interaction between the Notch and Integrin pathways. Appropriate statistical analysis methods were used to assess the significance of the experimental results and to ensure the scientific validity and reliability of the experimental design. We found that ECM- and EMT-related proteins were downregulated after ZLDI-8 treatment (P<0.05). ZLDI-8 significantly downregulated Integrinß1 and Integrinß3 in HCC in vitro and in vivo (P<0.05), possibly through Foxc2-dependent regulation. Mechanistically, interfering with the expression of both Integrin-linked kinase (ILK) and the NICD may downregulate the expression of proteins targeted by sorafenib, thereby sensitizing cells to sorafenib. The retroregulation of Integrinß by ILK may occur through the interaction between the NICD and ILK and may be the result of the translocation of the complexus. Our study indicates that blocking the Notch pathway may affect Integrinß through crosstalk between the Notch1 and Integrinß/ILK signaling pathways, thus providing a potential therapeutic strategy for HCC.


Assuntos
Proteína ADAM17 , Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Receptor Notch1 , Sorafenibe , Sorafenibe/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Humanos , Animais , Receptor Notch1/metabolismo , Receptor Notch1/genética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proteína ADAM17/metabolismo , Proteína ADAM17/antagonistas & inibidores , Camundongos Nus , Masculino , Cadeias beta de Integrinas/metabolismo , Cadeias beta de Integrinas/genética , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Camundongos
7.
Polymers (Basel) ; 16(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38201817

RESUMO

Under a global carbon-neutralizing environment, renewable wood is a viable alternative to non-renewable resources due to its abundance and high specific strength. However, fast-growing wood is hard to be applied extensively due to low mechanical strength and poor dimensional stability and durability. In this study, epoxy-acrylic resin-modified wood was prepared by forming a functional monomer system with three monomers [glycidyl methacrylate (GMA), maleic anhydride (MAN), and polyethylene glycol-200-dimethylacrylic acid (PEGDMA)] and filling into the wood cell cavity. The results showed that in the case of an optimal monomer system of nGMA:nPEGDMA = 20:1 and an optimal MAN dosage of 6%, the conversion rate of monomers reached 98.01%, the cell cavity was evenly filled by the polymer, with the cell wall chemically bonded. Thus, a bonding strength of as high as 1.13 MPa, a bending strength of 112.6 MPa and an impact toughness of 74.85 KJ/m2 were applied to the modified wood, which presented excellent dimensional stability (720 h water absorption: 26%, and volume expansion ratio: 5.04%) and rot resistance (loss rates from white rot and brown rot: 3.05% and 0.67%). Additionally, polymer-modified wood also exhibited excellent wear resistance and heat stability. This study reports a novel approach for building new environmentally friendly wood with high strength and toughness and good structural stability and durability.

8.
Arch Pharm (Weinheim) ; 357(2): e2300404, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38010470

RESUMO

Multitarget-directed ligands (MTDLs) have recently attracted significant interest due to their superior effectiveness in multifactorial Alzheimer's disease (AD). Combined inhibition of two important AD targets, glycogen synthase kinase-3ß (GSK-3ß) and dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A), may be a breakthrough in the treatment of AD. Based on our previous work, we have designed and synthesized a series of novel harmine derivatives, investigated their inhibition of GSK-3ß and DYRK1A, and evaluated a variety of biological activities. The results of the experiments showed that most of these compounds exhibited good activity against GSK-3ß and DYRK1A in vitro. ZLQH-5 was selected as the best compound due to the most potent inhibitory effect against GSK-3ß and DYRK1A. Molecular docking studies demonstrated that ZLQH-5 could form stable interactions with the ATP binding pocket of GSK-3ß and DYRK1A. In addition, ZLQH-5 showed low cytotoxicity against SH-SY5Y and HL-7702, good blood-brain barrier permeability, and favorable pharmacokinetic properties. More importantly, ZLQH-5 also attenuated the tau hyperphosphorylation in the okadaic acid SH-SY5Y cell model. These results indicated that ZLQH-5 could be a promising dual-target drug candidate for the treatment of AD.


Assuntos
Doença de Alzheimer , Neuroblastoma , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Glicogênio Sintase Quinase 3 beta , Harmina/farmacologia , Harmina/uso terapêutico , Proteínas tau/metabolismo , Proteínas tau/uso terapêutico , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Fosforilação
9.
Environ Sci Pollut Res Int ; 30(45): 101637-101652, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37656294

RESUMO

Environmental taxes and renewable energy consumption are becoming central policy instruments in countries especially in European Union (EU) countries to enhance environmental sustainability; however, no attention has been given to eco-innovations in the nexus between environmental taxes and carbon dioxide emission. This study investigates the effect of environmental taxes, innovations, and renewable energy consumption on CO2 emissions in 26 EU countries from 2000 to 2020. Panel quantile regression was employed for analysis where the results show that environmental taxes have both positive and negative influence on CO2 emissions across quantiles in different models, whereas renewable energy consumption considerably reduces carbon emissions. Economic growth causes an increase in CO2 emissions; however, the financial progress greatly reduces CO2 emissions. Eco-innovations and its square term have a negative influence on carbon emissions which shows that eco-innovations significantly reduce carbon dioxide emission. The findings have significant implications for public policy in the sample countries, notably in terms of promoting renewable energy sources and transitioning to green growth through eco-innovations in order to achieve environmental sustainability.


Assuntos
Dióxido de Carbono , Impostos , União Europeia , Desenvolvimento Econômico , Política Pública , Energia Renovável
10.
PLoS One ; 18(6): e0287543, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37352162

RESUMO

The majority of countries struggle to accomplish sustainable development and environmental sustainability; nevertheless, environmental degradation issues can be resolved by enhancing technological innovations and institutional effectiveness. This study assesses the impact of technological innovations and institutional quality on carbon dioxide emission in the Belt and road initiative countries for the time period of 2002 to 2019. Fixed effect, OLS, and generalized method of moment estimators were applied to the panel data for analysis. The results shows that energy from fossil fuels, economic growth and technological innovations increase environmental degradation by rising carbon dioxide emission. Renewable energy consumption, the rule of law, and the quality of institutions make a significant contribution to the improvement of environmental quality. In particular, the Environmental Kuznets Curve and Innovation Claudia curve is valid in the Belt and Road Initiative countries. In the presence of quality institutions, countries can achieve sustainable growth and environmental sustainability by expanding their use of green technology and renewable energy. The findings provide suggestions to the sample countries on the improvement of institutional framework and technological innovations in order to achieve sustainable development.


Assuntos
Dióxido de Carbono , Invenções , Dióxido de Carbono/análise , Energia Renovável , Combustíveis Fósseis , Desenvolvimento Econômico
11.
Front Optoelectron ; 16(1): 11, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37233874

RESUMO

An integrated microwave photonic mixer based on silicon photonic platforms is proposed, which consist of a dual-drive Mach-Zehnder modulator and a balanced photodetector. The modulated optical signals from microwave photonic links can be directly demodulated and down-converted to intermediate frequency (IF) signals by the photonic mixer. The converted signal is obtained by conducting off-chip subtraction of the outputs from the balanced photodetector, and subsequent filtering of the high frequency items by an electrical low-pass filter. Benefiting from balanced detection, the conversion gain of the IF signal is improved by 6 dB, and radio frequency leakage and common-mode noise are suppressed significantly. System-level simulations show that the frequency mixing system has a spurious-free dynamic range of 89 dB·Hz2/3, even with deteriorated linearity caused by the two cascaded modulators. The spur suppression ratio of the photonic mixer remains higher than 40 dB when the IF varies from 0.5 to 4 GHz. The electrical-electrical 3 dB bandwidth of frequency conversion is 11 GHz. The integrated frequency mixing approach is quite simple, requiring no extra optical filters or electrical 90° hybrid coupler, which makes the system more stable and with broader bandwidth so that it can meet the potential demand in practical applications.

12.
Small Methods ; 7(9): e2300152, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37203278

RESUMO

In recent years, layered oxides have been extensively studied as promising cathode materials for sodium ion batteries. However, layered oxides undergo complex phase transitions during charge-discharge process, which adversely affects the electrochemical performance. High-entropy layered oxides as a unique design concept can effectively improve the cycling performance of cathode materials by virtue of the 2D ion migration channels between the layers. Based on the concepts of high-entropy and layered oxides, this paper reviews the research status of high-entropy layered oxides in the field of sodium-ion batteries, focusing on the connection between high-entropy and layered oxide phase transitions during electrochemical charging and discharging. Finally, the advantages of layered cathode materials based high-entropy are summarized, and the opportunities and challenges of future high-entropy layered materials are proposed.

13.
Front Optoelectron ; 16(1): 6, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37036614

RESUMO

Due to the advantages of low propagation loss, wide operation bandwidth, continuous delay tuning, fast tuning speed, and compact footprints, chirped Bragg grating waveguide has great application potential in wideband phased array beamforming systems. However, the disadvantage of large group delay error hinders their practical applications. The nonlinear group delay spectrum is one of the main factors causing large group delay errors. To solve this problem, waveguides with nonlinear gradient widths are adopted in this study to compensate for the nonlinear effect of the grating apodization on the mode effective index. As a result, a linear group delay spectrum is obtained in the experiment, and the group delay error is halved.

14.
Environ Sci Pollut Res Int ; 30(24): 65149-65159, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37081366

RESUMO

Most of the developing and emerging countries are focusing to increase economic growth, enhance the living standard of the people, and reduce income inequality. Increasing economic growth through the factors such as agriculture, energy use for production, and other related activities can harm the environment. Considering this situation, this study utilizes data from the Belt and Road Initiative countries for the period of 1999 and 2018 to explore the nexus between income inequality, agricultural value added, and carbon dioxide using two-step system GMM model. The findings of the study indicate that income inequality, economic growth, energy consumption, and agriculture significantly contribute to an increase in carbon emissions and a decrease in environmental quality. On the other hand, the findings also indicate that manufacturing and service industries significantly contribute to an improvement in environmental quality by reducing carbon emissions. The findings lend even more credence to the environmental Kuznets curve, but the results do not indicate that there is a strong relationship between income inequality and economic growth. The outcomes of this study have crucial policy implications for the sample countries to build environmental regulations.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Humanos , Renda , Fatores Socioeconômicos , Agricultura
15.
Micromachines (Basel) ; 14(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36837946

RESUMO

This article presents the design method of a compact MEMS switched-line true-time delay line (TTDL) network over a wide frequency range extending from 2 to 42 GHz using TTDL units. The TTDL units, namely the cascading radio frequency micro-electromechanical system (RF MEMS) switches and GCPW, were employed in the proposed TTDL network to improve the delay-bandwidth product (DBW) while maintaining its compact size and low delay variation (DV). For comparison, a theoretical analysis of the RF MEMS switch was performed while observing the switch performance with various top electrodes. The MEMS TTDL network has a compact size of 5 mm × 5 mm, with a maximum delay of 200 ps and a minimum of 30 ps. The maximum insertion loss of 9 states is 10 dB, and the in/out return loss is better than 20 dB across 2-42 GHz. The group delay variations are within ±2.5% for all the delay states over the operating frequency range. To the best of our knowledge, the proposed TTDL network obtains the most control bits among the TTDL networks offered to date.

16.
Front Oncol ; 13: 1072054, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741016

RESUMO

Background: Hepatocellular carcinoma (HCC) is the major cause of malignancy-related deaths worldwide, and its incidence is likely to increase in the future as life expectancy increases. Therefore, the management of elderly patients with HCC has become a global issue. Aim of this study was to assess whether elderly patients with small HCC could obtain survival benefit from cryoablation (CRYO) in a real-world. Materials and methods: From July 2007 to June 2013, 185 patients with small HCC who underwent curative-intent percutaneous CRYO. All patients were divided into three groups according to age distribution. Overall survival (OS) and tumor-free survival (TFS) were compared between among of groups before and after the 1:1 propensity score matching, respectively. Univariate and multivariate Cox analyses were performed to determine the potential relationships between variables and prognostic outcomes. Results: One hundred and eighty-five patients (144 men, 41 women) received CRYO for small HCC, including 59 patients with age <50 years, 105 patients with age between 50 and 65 years, and 21 patients with age >65 years. The three age groups showed significant differences in the terms of underlying chronic liver disease and the number of patients with minor postoperative complications. After propensity score matching, the younger and elderly groups showed significant differences in mean OS (P=0.008) and tumor progression (P=0.050). However, no significant differences were shown in mean progression-free survival (PFS) (P=0.303). The Cox multivariate analysis showed that the Child-Pugh grade (HR=3.1, P<0.001), albumin (HR=0.85, P=0.004) and total of bilirubin (HR=1, P=0.024) were the independent prognostic factor for mean OS. Conclusion: Our propensity-score-matched study suggested that elderly patients with small HCC can achieve acceptable prognostic outcomes with PFS similar to those of younger patients with small HCC after treatment with CRYO, while Child-Pugh grade, bilirubin and serum albumin levels were associated with the prognosis of small HCCs.

17.
Biochem Genet ; 61(1): 410-427, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35943670

RESUMO

It has been reported that circRNAs play an important regulatory role in the progression of colorectal cancer (CRC). However, the molecular role of circ_0001821 in CRC development is unclear. In this study, we aimed to investigate the regulatory role and molecular mechanisms of circ_0001821 in CRC. Reverse transcription-quantitative PCR and western blot assays were used to detect the expression of circ_0001821, miR-600 and isochorismatase domain containing 1 (ISOC1) in CRC tissues as well as its cell lines. Colony formation assay and EDU assay were used to detect the proliferative capacity of cells. Transwell assay was used to assess cell migration and invasion ability. Flow cytometry was used to analyze cell apoptosis. ELISA was used to measure the glycolytic capacity of cells. Dual-luciferase reporter assay and RNA pull-down assay were used to analyze the relationships between circ_0001821, miR-600 and ISOC1. Animal experimentation was used to validate the functional study of circ_0001821 in vivo. Immunohistochemistry (IHC) of Ki67 staining analysis was conducted to assess tumor growth. Circ_0001821 and ISOC1 were significantly increased in CRC tissues and its cell lines, and miR-600 was significantly decreased in CRC tissues and its cell lines. Silencing circ_0001821 inhibited cell proliferation, migration, invasion and glycolytic capacity, while inducing apoptosis. And it could inhibit tumor growth in vivo. Circ_0001821 could act as a sponge for miR-600 to regulate CRC processes. ISOC1 was identified as a downstream regulator of miR-600, also miR-600 could regulate the expression of ISOC1. In addition, circ_0001821 could regulate ISOC1 expression changes through miR-600. Mechanistically, either miR-600 inhibitor or overexpression of ISOC1 could reverse the effects of knockdown of circ_0001821 on cell biological properties. Circ_0001821 regulated the developmental process of CRC through miR-600/ISOC1 axis.


Assuntos
Neoplasias Colorretais , MicroRNAs , Animais , Hidrolases , Apoptose , Proliferação de Células , Neoplasias Colorretais/genética , MicroRNAs/genética
18.
J Environ Manage ; 325(Pt B): 116604, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36308966

RESUMO

Vanadium slag (V-slag) is an important secondary V source, but other valuable elements are discarded in the tailings in industry. Herein, a green nitridation-corrosion process is proposed for the comprehensive recovery of valuable elements (V, Ti, Cr, Fe) from V-slag without producing hazardous waste. Thermodynamic results indicate that ammonia gas (NH3) can selectively reduce Fe and nitride V, Cr, and Ti. The main phase composition of the nitrided V-slag included metallic Fe, nitrides, and diopside under optimal conditions, and their relative contents were 42.5, 26.2, and 31.3%, respectively, after roasting at 1000 °C for 6 h. The effects of the main parameters on corrosion test were investigated, and the highest weight-gain ratio attained was 19.6%. FeOOH crystallizes on the surface of the nitrided V-slag due to the oxidization of metallic Fe. The phase evolution during the entire process is spinel/olivine/diopside → Fe/nitrides/diopside → FeOOH/nitrides/diopside. Owing to finer particle sizes, most FeOOH is separated by wet sieving (<1400 mesh). The purity of the enriched nitrides attained was 43% after pickling to remove excess Fe. The total recovery rates of Fe, V, Ti, Cr were 87.76%, 95.92%, 92.92%, 92.11%, respectively. This paper provides a sustainable strategy for the comprehensive utilization of V-slag, and guides the cleaner treatment of other similar minerals.

19.
Polymers (Basel) ; 14(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36501668

RESUMO

Wood is a viable alternative to traditional steel, cement, and concrete as a structural material for building applications, utilizing renewable resources and addressing the challenges of high energy consumption and environmental pollution in the construction industry. However, the vast supply of fast-growing poplar wood has bottlenecks in terms of low strength and dimensional stability, making it difficult to use as a structural material. An environmentally friendly acrylic resin system was designed and cured in this study to fill the poplar cell cavities, resulting in a new type of poplar laminated veneer lumber with improved mechanical strength and dimensional stability. The optimized acrylic resin system had a solid content of 25% and a curing agent content of 10% of the resin solid content. The cured filled poplar veneer gained 81.36% of its weight and had a density of 0.69 g/cm3. The static flexural strength and modulus of elasticity of the further prepared laminated veneer lumber were 123.12 MPa and 12,944.76 MPa, respectively, exceeding the highest flexural strength required for wood structural timber for construction (modulus of elasticity 12,500 MPa and static flexural strength 35 MPa). Its tensile strength, impact toughness, hardness, attrition value, water absorption, water absorption thickness expansion, and water absorption width expansion were 58.81%, 19.50%, 419.18%, 76.83%, 44.38%, 13.90%, and 37.60% higher than untreated laminated veneer lumber, demonstrating improved mechanical strength and dimensional stability, significantly. This method provides a novel approach to encouraging the use of low-value-added poplar wood in high-value-added structural building material applications.

20.
Front Oncol ; 12: 908189, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324566

RESUMO

Objective: The objective of the study was to explore the CT and ultrasound features and clinical significance of perivascular epithelioid cell tumor (PEComa) of the liver. Methods: Eleven hepatic PEComa patients treated in our hospital were retrospectively analyzed based on the characteristics of the imaging results of the patients, including conventional ultrasound, CDFI, contrast-enhanced ultrasound (CEUS), and contrast-enhanced CT (CECT). Results: CT scans showed that all lesions were hypodense. Ultrasonography showed that lesions were either hyperechoic (4/11, 36.36%), hypoechoic (4/11, 36.36%), isoechoic (1/11, 9.09%), or heterogeneously echoic (2/11, 18.18%). CDFI showed that most of the lesions had an abundant blood supply (9/11, 81.82%). Whether on CT scan or ultrasonography, the margins of the lesions were dominated by clear margins. Ultrasonography revealed more features: hyperechoic patterns around lesions (3/11, 27.27%) and lateral shadow (5/11, 45.45%). The CDFI showed that large blood vessels were observed around the lesions (9/11, 81.82%). CECT shows two enhancement patterns: "fast in and fast out (FIFO)" (8/11, 72.72%) and "fast in and slow out (FISO)" (3/11, 27.27%). CEUS shows that all lesions had the enhancement pattern of "FISO," which was different from CECT. All lesions displayed rapid enhancement during HAP in CEUS during 7-20 s. Four patients (36.36%) washed out at 60-180 s, another four (36.36%) washed out at 180-300 s, and the remaining three patients (27.27%) showed no signs of washout even at 360 s. Conclusion: Some imaging features, such as clear margins, peripheral hyperechoic around the lesion, lateral shadow, the large blood vessels around lesions, and the "FISO" enhancement pattern, may indicate expansive growth of the tumor and be helpful in the diagnosis of PEComa. Ultrasound images may provide more details for clinical reference.

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