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1.
Urolithiasis ; 52(1): 103, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960942

RESUMO

Kidney stones and infections significantly affect patients' health-related quality of life (HRQOL); however, the relationship between urinary tract infections (UTIs) and HRQOL in patients with kidney stones remains unclear. This study aimed to investigate the relationship using the validated Chinese version of the Wisconsin Stone Quality of Life questionnaire (C-WISQOL). We prospectively recruited 307 patients with kidney stones to complete the C-WISQOL before and after stone removal. The participants were diagnosed with UTI based on the presence of pyuria or bacteriuria with or without clinical symptoms. The psychometric properties of the C-WISQOL were statistically analyzed. Multivariate linear regression was used to predict the risk factors for impaired HRQOL in patients with stones and UTIs. The questionnaire is a reliable and robust tool for evaluating HRQOL in Chinese-speaking patients with urolithiasis. The UTI and kidney stone co-occurrence was significantly associated with female sex, diabetes mellitus, more previous stone events, higher antibiotic usage, positive stone- or UTI-related symptoms, and postoperative residual stones. The preoperative C-WISQOL scores and improvement in the HRQOL after stone removal in patients clinically diagnosed with UTI were significantly inferior to those in patients without UTI. The regression analyses showed that worse HRQOL was predicted by more previous stone events and positive stone- or UTI-related symptoms. In contrast, the presence of diabetes mellitus and postoperative residual stone fragments predicted a lower improvement in the HRQOL. These findings underscore UTI's harmful impact on perioperative HRQOL in patients with kidney stones and could help strategies benefit those patients.


Assuntos
Cálculos Renais , Qualidade de Vida , Infecções Urinárias , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Cálculos Renais/complicações , Cálculos Renais/cirurgia , Infecções Urinárias/psicologia , Infecções Urinárias/complicações , Infecções Urinárias/epidemiologia , Infecções Urinárias/etiologia , Estudos Prospectivos , Adulto , Inquéritos e Questionários/estatística & dados numéricos , Fatores de Risco , Idoso , Psicometria
2.
ACS Omega ; 9(22): 23984-23997, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38854515

RESUMO

The causative pathogen of COVID-19, severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), utilizes the receptor-binding domain (RBD) of the spike protein to bind to human receptor angiotensin-converting enzyme 2 (ACE2). Further cleavage of spike by human proteases furin, TMPRSS2, and/or cathepsin L facilitates viral entry into the host cells for replication, where the maturation of polyproteins by 3C-like protease (3CLpro) and papain-like protease (PLpro) yields functional nonstructural proteins (NSPs) such as RNA-dependent RNA polymerase (RdRp) to synthesize mRNA of structural proteins. By testing the tea polyphenol-related natural products through various assays, we found that the active antivirals prevented SARS-CoV-2 entry by blocking the RBD/ACE2 interaction and inhibiting the relevant human proteases, although some also inhibited the viral enzymes essential for replication. Due to their multitargeting properties, these compounds were often misinterpreted for their antiviral mechanisms. In this study, we provide a systematic protocol to check and clarify their anti-SARS-CoV-2 mechanisms, which should be applicable for all of the antivirals.

3.
J Environ Manage ; 363: 121332, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850906

RESUMO

This paper presents the synthesis of visible light-responsive ternary nanocomposites composed of cuprous oxide (Cu2O), tungsten trioxide (WO3), and titanium dioxide (TiO2) with varying weight percentages (wt.%) of the Cu2O. The resulting Cu2O/WO3/TiO2 (CWT) nanocomposites exhibited band gap energy ranging from 2.35 to 2.90 eV. Electrochemical and photoelectrochemical (PEC) studies confirmed a reduced recombination rate of photoexcited charge carriers in the CWT nanocomposites, facilitated by a direct Z-scheme heterojunction. The 0.50CWT nanocomposite demonstrated superior photodegradation activity (2.29 × 10-2 min-1) against Reactive Black 5 (RB5) dye under visible light activation. Furthermore, the 0.50CWT nanocomposite exhibited excellent stability with 80.51% RB5 photodegradation retention after five cycles. The 0.50CWT electrode achieved a maximum specific capacitance of 66.32 F/g at 10 mA/g current density, with a capacitance retention of 95.17% after 1000 charge-discharge cycles, affirming its stable and efficient supercapacitor performance. This was supported by well-defined peaks in cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) curves, indicating pseudocapacitive properties.


Assuntos
Cobre , Eletrodos , Luz , Nanocompostos , Titânio , Tungstênio , Nanocompostos/química , Titânio/química , Tungstênio/química , Cobre/química , Catálise , Óxidos/química
4.
J Biomol Struct Dyn ; 42(10): 5053-5071, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38764131

RESUMO

The synthesis of two new hexahydroisoquinoline-4-carbonitrile derivatives (3a and 3b) is reported along with spectroscopic data and their crystal structures. In compound 3a, the intramolecular O-H···O hydrogen bond constraints the acetyl and hydroxyl groups to be syn. In the crystal, inversion dimers are generated by C-H···O hydrogen bonds and are connected into layers parallel to (10-1) by additional C-H···O hydrogen bonds. The layers are stacked with Cl···S contacts 0.17 Å less than the sum of the respective van der Waals radii. The conformation of the compound 3b is partially determined by the intramolecular O-H···O hydrogen bond. A puckering analysis of the tetrahydroisoquinoline unit was performed. In the crystal, O-H···O and C-H···O hydrogen bonds together with C-H···π(ring) interactions form layers parallel to (01-1) which pack with normal van der Waals interactions. To understand the binding efficiency and stability of the title molecules, molecular docking, and 100 ns dynamic simulation analyses were performed with CDK5A1. To rationalize their structure-activity relationship(s), a DFT study at the B3LYP/6-311++G** theoretical level was also done. The 3D Hirshfled surfaces were also taken to investigate the crystal packings of both compounds. In addition, their ADMET properties were explored.Communicated by Ramaswamy H. Sarma.


Assuntos
Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Cristalografia por Raios X , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/metabolismo , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacologia , Conformação Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Modelos Moleculares , Nitrilas/química , Simulação de Dinâmica Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Humanos
5.
Chempluschem ; : e202400235, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760894

RESUMO

Electrodeposition of abundant metals to fabricate efficient and durable electrodes play a viable role in advancing renewable electrochemical energy technologies. Herein, we deposit Co9S8-Ag-Ni3S2@NF onto nickel foam (NF) to form Co9S8-Ag-Ni3S2@NF as a highly efficient electrode for oxygen evolution reaction (OER). The electrochemical investigation verifies that the Co9S8-Ag-Ni3S2@NF electrode exhibits superior electrocatalytic activity toward OER because of its nanoflowers' open-pore morphology, reduced overpotential (η10 = 125 mV), smaller charge transfer resistance, long-term stability, and a synergistic effect between various components, which allows the reactants to be more easily absorbed and subsequently converted into gaseous products during the water electrolysis process. DFT calculation also reveals that the introduction of Ag (222) surface into the Co9S8 (440)-Ni3S2 (120) system increases the electronic density of states per unit cell of a system and significantly reduces the energy barriers of intermediates for OER, leading to enhanced electrocatalytic activity for OER. This study showcases the innovation of employing trimetallic nanomaterials immobilized on a conductive, continuous porous three-dimensional network formed on a nickel foam (NF) substrate as a highly efficient catalyst for OER.

6.
J Liposome Res ; : 1-12, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38779944

RESUMO

Anti-glutamatergic agents may have neuroprotective effects against excitotoxicity that is known to be involved in the pathogenesis of Parkinson's disease (PD). One of these agents is kynurenic acid (KYNA), a tryptophan metabolite, which is an endogenous N-methyl-D-aspartic acid (NMDA) receptor antagonist. However, its pharmacological properties of poor water solubility and limited blood-brain barrier (BBB) permeability rules out its systemic administration in disorders affecting the central nervous system. Our aim in the present study was to investigate the neuroprotective effects of KYNA-loaded micelles (KYNA-MICs) against PD in vitro and in vivo. Lipid-based micelles (MICs) in conjunction with KYNA drug delivery have the potential to enhance the penetration of therapeutic drugs into a diseased brain without BBB obstacles. KYNA-MICs were characterized by particle size (105.8 ± 12.1 nm), loading efficiency (78.3 ± 4.23%), and in vitro drug release (approximately 30% at 24 h). The in vitro experiments showed that KYNA-MICs effectively reduced 2-fold protein aggregation. The in vivo studies revealed that KYNA was successfully delivered by 5-fold increase in neurotoxin-induced PD brains. The results showed significant enhancement of KYNA delivery into brain. We also found that the KYNA-MICs exhibited several therapeutic effects. The KYNA-MICs reduced protein aggregation of an in vitro PD model, ameliorated motor functions, and prevented loss of the striatal neurons in a PD animal model. The beneficial effects of KYNA-MICs are probably explained by the anti-excitotoxic activity of the treatment's complex. As the KYNA-MICs did not induce any appreciable side-effects at the protective dose applied to a chronic PD mouse model, our results demonstrate that KYNA provides neuroprotection and attenuates PD pathology.

7.
J Appl Crystallogr ; 57(Pt 2): 552-554, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38596744

RESUMO

The program FlɛX (flexural ɛ for xtals) has been developed for a quick, easy and accurate evaluation of the maximum deformation reached in flexible crystals from a simple optical microscope picture. The program takes advantage of computer vision libraries to find the contours of a bent crystal and fit these to semicircles. It can then calculate the theoretical maximum deformation along its long axis using equations from the Euler-Bernoulli beam theory.

8.
Heliyon ; 10(7): e28902, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38633652

RESUMO

Rhodanine is a heterocyclic organic compound that has been investigated for its potential biomedical applications, particularly in drug discovery. Rhodanine derivatives have been examined as the medication options for numerous illnesses, including cancer, inflammation, and infectious diseases. Some rhodanine derivatives have also shown promising activity against drug-resistant strains of bacteria and viruses. One of these derivatives is polyrhodanine (PR), a conducting polymer that has gained attention for its biomedical properties. This review article summarises the latest advancements in creating biomaterials based on PR for biosensing, antimicrobial treatments, and anticancer therapies. The distinctive characteristics of PR, such as biocompatibility, biodegradability, and good conductivity, render it an attractive candidate for these applications. The article also explores obstacles and potential future paths for advancing biomaterials made with PR, including synthesis modifications, characterisation techniques, and in vivo evaluation of biocompatibility and efficacy. Overall, as an emerging research topic, this review emphasises the potential of PR as a promising biomaterial for various biomedical applications and provides insights into the contemporary state of research and prospective directions for investigation.

9.
Clin Chim Acta ; 559: 119685, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663472

RESUMO

Early detection and effective cancer treatment are critical to improving metastatic cancer cell diagnosis and management today. In particular, accurate qualitative diagnosis of metastatic cancer cell represents an important step in the diagnosis of cancer. Today, biosensors have been widely developed due to the daily need to measure different chemical and biological species. Biosensors are utilized to quantify chemical and biological phenomena by generating signals that are directly proportional to the quantity of the analyte present in the reaction. Biosensors are widely used in disease control, drug delivery, infection detection, detection of pathogenic microorganisms, and markers that indicate a specific disease in the body. These devices have been especially popular in the field of metastatic cancer cell diagnosis and treatment due to their portability, high sensitivity, high specificity, ease of use and short response time. This article examines biosensors for metastatic cancer cells. It also studies metastatic cancer cells and the mechanism of metastasis. Finally, the function of biosensors and biomarkers in metastatic cancer cells is investigated.


Assuntos
Técnicas Biossensoriais , Metástase Neoplásica , Neoplasias , Humanos , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Técnicas Biossensoriais/métodos , Neoplasias/diagnóstico , Neoplasias/patologia
10.
Environ Int ; 186: 108548, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38513555

RESUMO

Large industrial emissions of volatile organic compounds (VOCs) from the petrochemical industry are a critical concern due to their potential carcinogenicity. VOC emissions vary in composition depending on the source and occur in mixtures containing compounds with varying degrees of toxicity. We proposed the use of carcinogenic equivalence (CEQ) and multivariate analysis to identify the major contributors to the carcinogenicity of VOC emissions. This method weights the carcinogenicity of each VOC by using a ratio of its cancer slope factor to that of benzene, providing a carcinogenic equivalence factor (CEF) for each VOC. We strategically selected a petrochemical industrial park in southern Taiwan that embodies the industry's comprehensive nature and serves as a representative example. The CEQs of different emission sources in three years were analyzed and assessed using principal component analysis (PCA) to characterize the major contributing sectors, vendors, sources, and species for the carcinogenicity of VOC emissions. Results showed that while the study site exhibited a 20.7 % (259.8 t) decrease in total VOC emissions in three years, the total CEQ emission only decreased by 4.5 % (15.9 t), highlighting a potential shift in the emitted VOC composition towards more carcinogenic compounds. By calculating CEQ followed by PCA, the important carcinogenic VOC emission sources and key compounds were identified. More importantly, the study compared three approaches: CEQ followed by PCA, PCA followed by CEQ, and PCA only. While the latter two methods prioritized sources based on emission quantities, potentially overlooking less abundant but highly carcinogenic compounds, the CEQ-first approach effectively identified vendors and sources with the most concerning cancer risks. This distinction underscores the importance of selecting the appropriate analysis method based on the desired focus. Our study highlighted how prioritizing CEQ within the analysis framework empowered the development of precise control measures that address the most carcinogenic VOC sources.


Assuntos
Poluentes Atmosféricos , Carcinógenos , Compostos Orgânicos Voláteis , Taiwan , Compostos Orgânicos Voláteis/análise , Carcinógenos/análise , Análise Multivariada , Poluentes Atmosféricos/análise , Análise de Componente Principal , Monitoramento Ambiental/métodos , Indústria de Petróleo e Gás , Humanos
11.
Cell Res ; 34(5): 345-354, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38467743

RESUMO

Neural signals can significantly influence cancer prognosis. However, how cancer cells may proactively modulate the nervous system to benefit their own survival is incompletely understood. In this study, we report an overlapping pattern of brain responses, including that in the paraventricular nucleus of the hypothalamus, in multiple mouse models of peripheral cancers. A multi-omic screening then identifies leukemia inhibitory factor (LIF) and galectin-3 (Gal3) as the key cytokines released by these cancer cell types to trigger brain activation. Importantly, increased plasma levels of these two cytokines are observed in patients with different cancers. We further demonstrate that pharmacologic or genetic blockage of cancer cell-derived LIF or Gal3 signaling abolishes the brain responses and strongly inhibits tumor growth. In addition, ablation of peripheral sympathetic actions can similarly restore antitumor immunity. These results have elucidated a novel, shared mechanism of multiple cancer cell types hijacking the nervous system to promote tumor progression.


Assuntos
Galectina 3 , Fator Inibidor de Leucemia , Transdução de Sinais , Animais , Humanos , Camundongos , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Tumoral , Galectina 3/metabolismo , Fator Inibidor de Leucemia/metabolismo , Camundongos Endogâmicos C57BL , Neoplasias/metabolismo , Neoplasias/patologia
12.
Chemosphere ; 356: 141800, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554860

RESUMO

In pursuit of advancing photocatalysts for superior performance in water treatment and clean energy generation, researchers are increasingly focusing on layered double hydroxides (LDHs) which have garnered significant attention due to their customizable properties, morphologies, distinctive 2D layered structure and flexible options for modifying anions and cations. No review has previously delved specifically into ZnCr and NiCr LDH-based photocatalysts and therefore, this review highlights the recent surge in ZnCr and NiCr-based LDHs as potential photocatalysts for their applications in water purification and renewable energy generation. The structural and fundamental characteristics of layered double hydroxides and especially ZnCr-LDHs and NiCr-LDHs are outlined. Further, the various synthesis techniques for the preparation of ZnCr-LDHs, NiCr-LDHs and their composite and heterostructure materials have been briefly discussed. The applicability of ZnCr-LDH and NiCr-LDH based photocatalysts in tackling significant issues in water treatment and sustainable energy generation is the main emphasis of this review. It focuses on photocatalytic degradation of organic pollutants in wastewater, elucidating the principles and advancements for enhancing the efficiency of these materials. It also explores their role in H2 production through water splitting, conversion of CO2 into valuable fuels and NH3 synthesis from N2, shedding light on their potential for clean energy solutions. The insights presented herein offer valuable guidance for researchers working towards sustainable solutions for environmental remediation and renewable energy generation.


Assuntos
Hidróxidos , Purificação da Água , Hidróxidos/química , Catálise , Purificação da Água/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Energia Renovável , Águas Residuárias/química
13.
PLoS One ; 19(2): e0292737, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324619

RESUMO

The transition towards renewable energy sources necessitates efficient energy storage systems to meet growing demands. Electrochemical capacitors, particularly electric double-layer capacitors (EDLCs), show promising performance due to their superior properties. However, the presence of resistance limits their performance. This study explores using an external magnetic field to mitigate ion transfer resistance and enhance capacitance in magnetite-reduced graphene oxide (M-rGO) nanocomposites. M-rGO nanocomposites with varying weight ratios of magnetite were synthesized and comprehensively characterized. Characterization highlighted the difference in certain parameters such as C/O ratio, the Id/Ig ratio, surface area and particle size that contribute towards alteration of M-rGO's capacitive behaviour. Electrochemical studies demonstrated that applying a magnetic field increased specific capacitance by approximately 20% and reduced resistance by 33%. Notably, a maximum specific capacitance of 16.36 F/g (at a scan rate of 0.1 V/s) and 27.24 F/g (at a current density of 0.25 A/g) was achieved. These improvements were attributed to enhanced ion transportation and migration at the electrode/electrolyte interface, lowering overall resistance. However, it was also observed that the aforementioned parameters can also limit the M-rGO's performance, resulting in saturated capacitive state despite a reduced resistance. The integration of magnetic fields enhances energy storage in nanocomposite systems, necessitating further investigation into underlying mechanisms and practical applications.


Assuntos
Óxido Ferroso-Férrico , Grafite , Nanocompostos , Capacitância Elétrica , Campos Magnéticos
15.
Chem Rec ; : e202300303, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38314935

RESUMO

Nanotechnology has emerged as a pivotal tool in biomedical research, particularly in developing advanced sensing platforms for disease diagnosis and therapeutic monitoring. Since gold nanoparticles are biocompatible and have special optical characteristics, they are excellent choices for surface-enhanced Raman scattering (SERS) sensing devices. Integrating fluorescence characteristics further enhances their utility in real-time imaging and tracking within biological systems. The synergistic combination of SERS and fluorescence enables sensitive and selective detection of biomolecules at trace levels, providing a versatile platform for early cancer diagnosis and drug monitoring. In cancer detection, AuNPs facilitate the specific targeting of cancer biomarkers, allowing for early-stage diagnosis and personalized treatment strategies. The enhanced sensitivity of SERS, coupled with the tunable fluorescence properties of AuNPs, offers a powerful tool for the identification of cancer cells and their microenvironment. This dual-mode detection not only improves diagnostic accuracy but also enables the monitoring of treatment response and disease progression. In drug detection, integrating AuNPs with SERS provides a robust platform for identifying and quantifying pharmaceutical compounds. The unique spectral fingerprints obtained through SERS enable the discrimination of drug molecules even in complex biological matrices. Furthermore, the fluorescence property of AuNPs makes it easier to track medication distribution in real-time, maximizing therapeutic effectiveness and reducing adverse effects. Furthermore, the review explores the role of gold fluorescence nanoparticles in photodynamic therapy (PDT). By using the complementary effects of targeted drug release and light-induced cytotoxicity, SERS-guided drug delivery and photodynamic therapy (PDT) can increase the effectiveness of treatment against cancer cells. In conclusion, the utilization of gold fluorescence nanoparticles in conjunction with SERS holds tremendous potential for revolutionizing cancer detection, drug analysis, and photodynamic therapy. The dual-mode capabilities of these nanomaterials provide a multifaceted approach to address the challenges in early diagnosis, treatment monitoring, and personalized medicine, thereby advancing the landscape of biomedical applications.

16.
Acta Ophthalmol ; 102(5): e762-e773, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38279584

RESUMO

PURPOSE: To evaluate the structural, microvascular, and functional progression of normal tension glaucoma (NTG) with or without high myopia by examining longitudinal changes in optical coherence tomography angiography (OCTA) and visual field (VF) parameters. METHODS: We evaluated 61 NTG eyes and classified 25 of the eyes with axial lengths (ALs) of ≥26 mm as highly myopic. We assessed the rate of change in OCTA parameters, namely radial peripapillary capillary (RPC) vessel density (VD), parafovea VD, deep parafovea VD, retinal nerve fibre layer (RNFL) thickness, and ganglion cell complex thickness. We evaluated the correlation of the rate of change in OCTA parameters with VF loss and AL. RESULTS: Among the 61 NTG eyes, rates of loss of RPC VD, parafovea VD, deep parafovea VD, and RNFL thickness were significantly different from zero despite the nonsignificant rate of change in VF mean deviation (MD). Changes in these OCTA parameters did not differ significantly in highly myopic NTG eyes. The rate of change in VF MD was significantly correlated with the rate of change in parafovea VD in highly myopic and non-highly myopic NTG eyes. In highly myopic NTG eyes, AL was negatively correlated with the rates of loss of RNFL thickness, VF MD, and VF PSD. CONCLUSION: NTG eyes with a relatively stable VF exhibited loss of VD and RNFL thickness. VF progression in NTG was correlated with decreasing parafovea VD, indicating a structure-function correlation. Greater AL may indicate faster VF loss and RNFL thinning in highly myopic NTG eyes.


Assuntos
Angiofluoresceinografia , Pressão Intraocular , Glaucoma de Baixa Tensão , Fibras Nervosas , Disco Óptico , Células Ganglionares da Retina , Tomografia de Coerência Óptica , Campos Visuais , Humanos , Tomografia de Coerência Óptica/métodos , Glaucoma de Baixa Tensão/fisiopatologia , Glaucoma de Baixa Tensão/diagnóstico , Masculino , Feminino , Campos Visuais/fisiologia , Pessoa de Meia-Idade , Angiofluoresceinografia/métodos , Células Ganglionares da Retina/patologia , Fibras Nervosas/patologia , Pressão Intraocular/fisiologia , Disco Óptico/irrigação sanguínea , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Idoso , Seguimentos , Progressão da Doença , Miopia Degenerativa/fisiopatologia , Miopia Degenerativa/diagnóstico , Miopia Degenerativa/complicações , Estudos Retrospectivos , Fundo de Olho
17.
IEEE Trans Biomed Circuits Syst ; 18(3): 539-551, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38198255

RESUMO

A CMOS analog front-end (AFE) local-field potential (LFP) chopper amplifier with stimulation artifact tolerance, improved right-leg driven (RLD) circuit, and improved auxiliary path is proposed. In the proposed CMOS AFE LFP chopper amplifier, common-mode artifact voltage (CMAV) and differential-mode artifact voltage (DMAV) removal using the analog template removal method are proposed to achieve good signal linearity during stimulation. An improved auxiliary path is employed to boost the input impedance and allow the negative stimulation artifact voltage passing through. The common-mode noise is suppressed by the improved RLD circuit. The chip is implemented in 0.18- µm CMOS technology and the total chip area is 5.46-mm2. With the improved auxiliary path, the measured input impedance is larger than 133 M[Formula: see text] in the signal bandwidth and reaches 8.2 G[Formula: see text] at DC. With the improved RLD circuit, the measured CMRR is 131 - 144 dB in the signal bandwidth. Under 60-µs pulse width and 130-Hz constant current stimulation (CCS) with ±1-V CMAV and ±50-mV DMAV, the measured THD at the SC Amp output of fabricated AFE LFP chopper amplifier is 1.28%. The measurement results of In vitro agar tests have shown that with ±1.6-mA CCS pulses injecting to agar, the measured THD is 1.69%. Experimental results of both electrical and agar tests have verified that the proposed AFE LFP chopper amplifier has good stimulation artifact tolerance. The proposed CMOS AFE LFP chopper amplifier with analog template removal method is suitable for real-time closed-loop deep drain stimulation (DBS) SoC applications.


Assuntos
Amplificadores Eletrônicos , Artefatos , Estimulação Encefálica Profunda , Desenho de Equipamento , Estimulação Encefálica Profunda/instrumentação , Humanos , Processamento de Sinais Assistido por Computador/instrumentação
18.
Technol Health Care ; 32(2): 997-1013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37545282

RESUMO

BACKGROUND: Scheduling patient appointments in hospitals is complicated due to various types of patient examinations, different departments and physicians accessed, and different body parts affected. OBJECTIVE: This study focuses on the radiology scheduling problem, which involves multiple radiological technologists in multiple examination rooms, and then proposes a prototype system of computer-aided appointment scheduling based on information such as the examining radiological technologists, examination departments, the patient's body parts being examined, the patient's gender, and the patient's age. METHODS: The system incorporated a stepwise multiple regression analysis (SMRA) model to predict the number of examination images and then used the K-Means clustering with a decision tree classification model to classify the patient's examination time within an appropriate time interval. RESULTS: The constructed prototype creates a feasible patient appointment schedule by classifying patient examination times into different categories for different patients according to the four types of body parts, eight hospital departments, and 10 radiological technologists. CONCLUSION: The proposed patient appointment scheduling system can schedule appointment times for different types of patients according to the type of visit, thereby addressing the challenges associated with diversity and uncertainty in radiological examination services. It can also improve the quality of medical treatment.


Assuntos
Agendamento de Consultas , Radiologia , Humanos , Departamentos Hospitalares , Hospitais , Computadores
19.
Environ Res ; 243: 117840, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38081342

RESUMO

Since the establishment of the first global refinery in 1856, crude oil has remained one of the most lucrative natural resources worldwide. However, during the extraction process from reservoirs, crude oil gets contaminated with sediments, water, and other impurities. The presence of pressure, shear forces, and surface-active compounds in crude oil leads to the formation of unwanted oil/water emulsions. These emulsions can take the form of water-in-oil (W/O) emulsions, where water droplets disperse continuously in crude oil, or oil-in-water (O/W) emulsions, where crude oil droplets are suspended in water. To prevent the spread of water and inorganic salts, these emulsions need to be treated and eliminated. In existing literature, different demulsification procedures have shown varying outcomes in effectively treating oil/water emulsions. The observed discrepancies have been attributed to various factors such as temperature, salinity, pH, droplet size, and emulsifier concentrations. It is crucial to identify the most effective demulsification approach for oil/water separation while adhering to environmental regulations and minimizing costs for the petroleum sector. Therefore, this study aims to explore and review recent advancements in two popular demulsification techniques: chemical demulsification and magnetic nanoparticles-based (MNP) demulsification. The advantages and disadvantages of each technique are assessed, with the magnetic approach emerging as the most promising due to its desirable efficiency and compliance with environmental and economic concerns. The findings of this report are expected to have a significant impact on the overall process of separating oil and water, benefiting the oil and gas industry, as well as other relevant sectors in achieving the circular economy.


Assuntos
Nanopartículas , Petróleo , Emulsões/química , Emulsificantes , Recursos Naturais
20.
Chemosphere ; 349: 140890, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072201

RESUMO

There is much interest in developing metal-free halogenated graphene such as fluorinated graphene for various catalytic applications. In this work, a fluorine-doped graphene oxide photocatalyst was investigated for photocatalytic oxidation (PCO) of a volatile organic compound (VOC), namely gaseous methanol. The fluorination process of graphene oxide (GO) was carried out via a novel and facile solution-based photoirradiation method. The fluorine atoms were doped on the surface of the GO in a semi-ionic C-F bond configuration. This presence of the semi-ionic C-F bonds induced a dramatic 7-fold increment of the hole charge carrier density of the photocatalyst. The fluorinated GO photocatalyst exhibited excellent photodegradation up to 93.5% or 0.493 h-1 according pseudo-first order kinetics for methanol. In addition, 91.7% of methanol was mineralized into harmless carbon dioxide (CO2) under UV-A irradiation. Furthermore, the photocatalyst demonstrated good stability in five cycles of methanol PCO. Besides methanol, other VOCs such as acetone and formaldehyde were also photodegraded. This work reveals the potential of fluorination in producing effective graphene-based photocatalyst for VOC removal.


Assuntos
Grafite , Compostos Orgânicos Voláteis , Grafite/química , Metanol/química , Flúor/química
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