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1.
Indian Heart J ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38871218

RESUMEN

Residual Syntax Score (RSS) is derived from Syntax Score to quantify the burden of residual coronary artery disease after percutaneous coronary intervention (PCI). As data is limited, we report predictive utility of Residual SYNTAX Score in relation to in hospital and 1 year mortality of the patients undergoing percutaneous coronary intervention (PCI).

2.
Chemosphere ; 361: 142513, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38830462

RESUMEN

This study focused on evaluating the efficacy of a magnetic activated carbon material (CPAC@Fe3O4) derived from pods of copper pod tree in adsorbing the toxic herbicide, 2,4- (2,4-D) from aqueous solutions. The synthesized CPAC@Fe3O4 adsorbent, underwent various characterization techniques. FESEM images indicated a rough surface, incorporating iron oxide nanoparticles, while EDS analysis confirmed the presence of elements like Fe, O, and C. Notably, the CPAC@Fe3O4 exhibited high surface area (749.10 m2/g) and pore volume (0.5351 cm³/g), confirming its mesoporous nature. XRD investigations identified distinct signals associated with graphitic carbon and magnetite nanoparticles, while VSM analysis verified its magnetic properties with a high magnetic saturation value (2.72 emu/g). The adsorption process was exothermic, with a decrease in adsorption capacity at higher temperatures. Freundlich isotherm provided the best fit for the adsorption, and the pseudo-second-order equation effectively described the kinetics. Remarkably, the maximum adsorption capacity ranged from 246.43 to 261.03 mg/g, surpassing previously reported values. The ΔH° value (-8.67 kJ/mol) suggested a physisorption mechanism, and the negative ΔG° values established the spontaneous nature. Furthermore, the synthesized adsorbent demonstrated exceptional reusability, allowing for up to five cycles of adsorption-desorption operations. When applied to simulated agricultural runoff, CPAC@Fe3O4 showcased a significant adsorption capacity of 160.71 mg/g for 50 mg/L 2,4-D, using a 0.2 g/L dosage at pH 2. This study showcased the transformation of copper pod biomass into a valuable magnetic nanoadsorbent capable of efficiently eliminating the noxious 2,4-D pollutant from aqueous environments.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético , Biomasa , Carbón Orgánico , Herbicidas , Nanocompuestos , Contaminantes Químicos del Agua , Ácido 2,4-Diclorofenoxiacético/química , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Carbón Orgánico/química , Herbicidas/química , Nanocompuestos/química , Cinética , Purificación del Agua/métodos , Agricultura/métodos , Nanopartículas de Magnetita/química , Termodinámica , Concentración de Iones de Hidrógeno
3.
Environ Res ; 255: 119139, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750996

RESUMEN

As wastewater contains a variety of contaminating bacteria and oily residues, there is an urgent need for environmentally safe bactericidal agents and surfactants which can be applied for wastewater treatment. The present study emphasizes on the potential of hydrophobin-like protein (HFB-NJ1) extracted from sporulating mycelia of Aspergillus sp. NJ1 for wastewater treatment. The purified HFB-NJ1, depicted the presence of one single protein band of molecular size approximately 11-12 kDa on silver-stained SDS-PAGE gel. HFB-NJ1 also presented properties such as surface modification of glass and stable emulsification of sunflower oil. HFB-NJ1 depicted exceptional antibacterial activity against bacterial pathogens such as Bacillus subtilis and Pseudomonas aeruginosa at low MIC of 0.5 µg/mL and 0.75 µg/mL respectively. Additionally, HFB-NJ1 depicted enhanced emulsification of various vegetable and petroleum-based oils (E24 > 80%). HFB-NJ1 effectively reduced gold ions, producing nanospheres with a size of 15.33 nm - a recognized antimicrobial agent. This study underscores the multifunctional attributes of HFB-NJ1, highlighting its efficacy in removing pathogenic bacteria, emulsifying organic compounds from wastewater, and demonstrating a reduction ability for nanoparticle synthesis.


Asunto(s)
Proteínas Fúngicas , Aguas Residuales , Aguas Residuales/química , Proteínas Fúngicas/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Aspergillus/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Eliminación de Residuos Líquidos/métodos , Bacillus subtilis/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Purificación del Agua/métodos
6.
Turk Kardiyol Dern Ars ; 52(3): 189-198, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38573091

RESUMEN

OBJECTIVE: Significant involvement of the cardiovascular system is known in multisystem inflammatory syndrome in children (MIS-C). This study aimed to examine the recovery of affected cardiovascular parameters over a medium-term follow-up. METHODS: A cohort of 69 children was studied prospectively. Assessments of left ventricular (LV) function and coronary artery abnormalities (CAA) were conducted at admission, 1.5 months, and 3 months. Coronavirus Disease 2019 (COVID-19) antibody titers were assessed at these three time points. Echocardiographic and antibody parameters (rising/decreasing) were analyzed for correlation. Outcomes were assessed using logistic regression. RESULTS: At admission, among the 78.2% of patients who were tested, 88.9% tested positive for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). A quarter of the patients had pericardial effusion, and half had valvulitis. Decreased ejection fraction, global circumferential strain (GCS), and global longitudinal strain (GLS) were seen in 54.4%, 68.6%, and 35.8% of patients, respectively. CAAs were observed in 27.78% of patients. Systolic dysfunction was significantly associated with older age. During follow-up, severe LV dysfunction normalized within 6-7 weeks, while mild to moderate dysfunction reached normalcy by two weeks. Both GCS and GLS reached normalcy within a median of two weeks. Diastolic parameters recovered by six weeks. Most small and moderate coronary aneurysms resolved, but a giant aneurysm in an infant remained large even after 15 months. Trends in antibodies and ejection fraction (EF) at three months were significantly correlated. Admission EF, GLS (at 6 weeks) and deceleration time (at 3 months) were significantly associated with intensive care unit (ICU) admission. The median segmental strain of the cohort remained low in certain segments at three months. CONCLUSION: Smaller CAAs resolve, whereas giant CAAs persist. EF and GLS are important predictors of Pediatric Intensive Care Unit (PICU) stay. The residual impairment of median segmental strain and persistent diastolic dysfunction at three months indicate the need for long-term follow-up.


Asunto(s)
COVID-19 , COVID-19/complicaciones , Ecocardiografía , Síndrome de Respuesta Inflamatoria Sistémica , Lactante , Humanos , Niño , Estudios de Seguimiento , COVID-19/diagnóstico por imagen , SARS-CoV-2
7.
Environ Res ; 252(Pt 2): 118816, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38570126

RESUMEN

The current investigation reports the usage of adaptive neuro-fuzzy inference system (ANFIS) and artificial neural network (ANN), the two recognized machine learning techniques in modelling tetracycline (TC) adsorption onto Cynometra ramiflora fruit biomass derived activated carbon (AC). Many characterization methods utilized, confirmed the porous structure of synthesized AC. ANN and ANFIS models utilized pH, dose, initial TC concentration, mixing speed, time duration, and temperature as input parameters, whereas TC removal percentage was designated as the output parameter. The optimized configuration for the ANN model was determined as 6-8-1, while the ANFIS model employed trimf input and linear output membership functions. The obtained results showed a strong correlation, indicated by high R2 values (ANNR2: 0.9939 & ANFISR2: 0.9906) and low RMSE values (ANNRMSE: 0.0393 & ANFISRMSE: 0.0503). Apart from traditional isotherms, the dataset was fitted to statistical physics models wherein, the double-layer with a single energy satisfactorily explained the physisorption mechanism of TC adsorption. The sorption energy was 21.06 kJ/mol, and the number of TC moieties bound per site (n) was found to be 0.42, conclusive of parallel binding of TC molecules to the adsorbent surface. The adsorption capacity at saturation (Qsat) was estimated to be 466.86 mg/g - appreciably more than previously reported values. These findings collectively demonstrate that the AC derived from C. ramiflora fruit holds great potential for efficient removal of TC from a given system, and machine learning approaches can effectively model the adsorption processes.


Asunto(s)
Biomasa , Carbón Orgánico , Aprendizaje Automático , Redes Neurales de la Computación , Tetraciclina , Adsorción , Tetraciclina/química , Tetraciclina/análisis , Carbón Orgánico/química , Frutas/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis
8.
Biomed Phys Eng Express ; 10(4)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38640907

RESUMEN

Cardiac electrical changes associated with ischemic heart disease (IHD) are subtle and could be detected even in rest condition in magnetocardiography (MCG) which measures weak cardiac magnetic fields. Cardiac features that are derived from MCG recorded from multiple locations on the chest of subjects and some conventional time domain indices are widely used in Machine learning (ML) classifiers to objectively distinguish IHD and control subjects. Most of the earlier studies have employed features that are derived from signal-averaged cardiac beats and have ignored inter-beat information. The present study demonstrates the utility of beat-by-beat features to be useful in classifying IHD subjects (n = 23) and healthy controls (n = 75) in 37-channel MCG data taken under rest condition of subjects. The study reveals the importance of three features (out of eight measured features) namely, the field map angle (FMA) computed from magnetic field map, beat-by-beat variations of alpha angle in the ST-T region and T wave magnitude variations in yielding a better classification accuracy (92.7 %) against that achieved by conventional features (81 %). Further, beat-by-beat features are also found to augment the accuracy in classifying myocardial infarction (MI) Versus control subjects in two public ECG databases (92 % from 88 % and 94 % from 77 %). These demonstrations summarily suggest the importance of beat-by-beat features in clinical diagnosis of ischemia.


Asunto(s)
Aprendizaje Automático , Magnetocardiografía , Isquemia Miocárdica , Humanos , Magnetocardiografía/métodos , Isquemia Miocárdica/fisiopatología , Isquemia Miocárdica/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Estudios de Casos y Controles , Procesamiento de Señales Asistido por Computador , Algoritmos , Electrocardiografía/métodos , Anciano , Frecuencia Cardíaca/fisiología , Corazón/fisiopatología , Reproducibilidad de los Resultados
9.
Indian Heart J ; 76(2): 108-112, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38452813

RESUMEN

BACKGROUND: The data on prognostic values of SYNTAX score II in patients undergoing percutaneous coronary intervention is limited. We report predictive utility of SYNTAX score II in relation to in hospital and 1 year mortality of the patients undergoing percutaneous coronary intervention. METHODS: This was a cohort study of patients who underwent percutaneous coronary intervention (PCI) at a single centre from January 2018 to December 2019. In hospital and 12-month events and mortality was analysed among 1000 patients. The patients were divided into 3 groups based on tertiles of Syntax II score (<22, 22-27.7 and >27.7). RESULT: The total mortality at 12 months was 60 (6%). Major adverse cardiac events (MACE) occurred in 87 (9%). The patients who died had higher SYNTAX score II score compared to those alive at 12 months 34 (38, 24) vs 24 (28.1, 20.9) P < 0.01. The same trend was seen in patients who had major adverse cardiac events (MACE) 28 (34, 24) vs 24 (28.6, 21) P < 0.01 Among the 3 groups of SYNTAX score II, in hospital mortality, all-cause mortality, cardiovascular death, myocardial infarction, unstable angina, revascularization and major adverse cardiac events (MACE) were higher in the third tertile (>27.7) compared the lower tertiles. CONCLUSION: The patients who had higher SYNTAX score II had more in hospital and 12 month mortality and major adverse cardiac events (MACE). SYNTAX II score is a better predictor of in-hospital, and 12 month cardiovascular and all cause mortality.


Asunto(s)
Angiografía Coronaria , Enfermedad de la Arteria Coronaria , Mortalidad Hospitalaria , Intervención Coronaria Percutánea , Humanos , Intervención Coronaria Percutánea/métodos , Femenino , Masculino , Enfermedad de la Arteria Coronaria/cirugía , Enfermedad de la Arteria Coronaria/diagnóstico , Pronóstico , Persona de Mediana Edad , Mortalidad Hospitalaria/tendencias , Estudios Retrospectivos , Estudios de Seguimiento , Tasa de Supervivencia/tendencias , Anciano , Medición de Riesgo/métodos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Factores de Riesgo
10.
Environ Res ; 250: 118414, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38365050

RESUMEN

The present study reports the synthesis, characterization, and application of sustainable magnetic biochar composite. The inedible fruits of Vateria indica, a powerful ayurvedic plant were hydrothermally transformed into magnetic biochar (BC-Fe3O4) in a single step and characterized by several sophisticated techniques. FESEM analysis portrayed fibrous irregular mesh-like biochar with surface clustered Fe3O4 nanoparticles, while the incidence of carbon, oxygen, and iron in the elemental analysis by EDS established magnetic biochar formation. Numerous peaks consistent with planes of (220), (311), (400), (422), (511), (440), and (120) also substantiated the occurrence of magnetite nanoparticles and biochar respectively, as analyzed by XRD. XPS analysis showed signals at 285.65 eV, 533.28 eV, 711.08 eV, and 724.68 eV corroborating a strong C-O bond, O1s orbit, Fe2+, and Fe3+ respectively. BC-Fe3O4 was superparamagnetic with saturation magnetization of 4.74 emu/g, as per VSM studies, while its specific surface area, pore volume, and pore diameter were 5.74 m2/g, 0.029 cm3/g, and 20.86 nm respectively. The Fenton-like degradation of methylene blue (5.0-25.0 ppm) was accomplished by synthesized BC-Fe3O4, in the presence of H2O2. Within 180 min, almost complete degradation was achieved, with first-order kinetics having rate constants between 0.0299 and 0.0167 min-1. Stability and recyclability studies performed over 7 cycles exhibited unaltered degradation between 93.98 and 97.59%. This study exhibits the exceptional characteristics and degradation capabilities of BC-Fe3O4 synthesized from a sustainable plant biomass.


Asunto(s)
Carbón Orgánico , Carbón Orgánico/química , Frutas/química , Colorantes/química , Peróxido de Hidrógeno/química , Hierro/química , Catálisis , Contaminantes Químicos del Agua/química
11.
Indian Pacing Electrophysiol J ; 24(2): 119-121, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38355014

RESUMEN

Lead reversals are a common cause of electrocardiographic abnormality, which can lead to a false diagnosis like chamber enlargement, myocardial ischemia or infarction. Isolated limb lead reversals and chest lead reversals are common in clinical practice. This article reports a rare case where multiple limb and chest leads were reversed due to the reversal of cables leading to a false diagnosis of myocardial ischemia.

12.
Biomed Phys Eng Express ; 10(2)2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38277702

RESUMEN

Background. Magnetocardiography (MCG) is a non-invasive and non-contact technique that measures weak magnetic fields generated by the heart. It is highly effective in the diagnosis of heart abnormalities. Multichannel MCG provides detailed spatio-temporal information of the measured magnetic fields. While multichannel MCG systems are costly, usage of the optimal number of measurement channels to characterize cardiac magnetic fields without any appreciable loss of signal information would be economically beneficial and promote the widespread use of MCG technology.Methods. An optimization method based on the sequential selection approach is used to choose channels containing the maximum signal information while avoiding redundancy. The study comprised 40 healthy individuals, along with two subjects having ischemic heart disease and one subject with premature ventricular contraction. MCG measured using a 37 channel MCG system. After revisiting the existing methods of optimization, the mean error and correlation of the optimal set of measurement channels with those of all 37 channels are evaluated for different sets, and it has been found that 18 channels are adequate.Results. The chosen 18 optimal channels exhibited a strong correlation (0.99 ± 0.006) between the original and reconstructed magnetic field maps for a cardiac cycle in healthy subjects. The root mean square error is 0.295 pT, indicating minimal deviation.Conclusion. This selection method provides an efficient approach for choosing MCG, which could be used for minimizing the number of channels as well as in practical unforeseen measurement conditions where few channels are noisy during the measurement.


Asunto(s)
Magnetocardiografía , Complejos Prematuros Ventriculares , Humanos , Magnetocardiografía/métodos , Análisis Costo-Beneficio , Corazón , Electrocardiografía
13.
Pacing Clin Electrophysiol ; 47(2): 239-241, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38264970

RESUMEN

A 51-year-old female with congenitally corrected transposition of great arteries (CCTGA), situs solitus, dextrocardia, atrial septal defect and persistent left superior vena cava underwent electrophysiology study for recurrent palpitations with documented narrow complex, short RP tachycardia. With a catheter in the region of the anterior mitral annulus, a His signal was recorded and HV interval was 35 msec. Tachycardia was induced with a ventricular extrastimulus. During the tachycardia there was 1:1 ventriculo-atrial conduction and central atrial activation with a VA interval of 20 msec. The recorded His signal could be seen after the QRS. What is the mechanism of the tachycardia?


Asunto(s)
Transposición de los Grandes Vasos , Femenino , Humanos , Persona de Mediana Edad , Transposición Congénitamente Corregida de las Grandes Arterias , Transposición de los Grandes Vasos/complicaciones , Transposición de los Grandes Vasos/cirugía , Vena Cava Superior , Taquicardia , Frecuencia Cardíaca
14.
Chemosphere ; 350: 141130, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38185425

RESUMEN

The adsorption properties of 2,4-Dichlorophenoxyacetic acid (2,4-D) onto biochar, obtained through HCl-assisted hydrothermal carbonization process of Vateria indica fruits (VI-BC), were extensively studied using traditional and statistical physics approaches. The traditional adsorption investigations encompassed kinetics, equilibrium, and thermodynamics studies. Subsequently, the Hill statistical physics model was employed to interpret the mechanism. Also, artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) machine learning tools were successfully employed to model the adsorption data wherein both models had high prediction potential (R2 > 0.99). The outcomes demonstrated that the produced VI-BC exhibited remarkable adsorptive traits, having a considerable specific surface area (111.54 m2/g), pore size (5.89 nm), a variety of functional groups, and appropriate attributes for efficiently adsorbing 2,4-D. For 10 mg/L 2,4-D, at pH 2.0 and with 0.3 g/L dose, an impressive 91.67% adsorption efficiency was achieved within a 120-min. Pseudo-second-order model aptly depicted the kinetic behavior of 2,4-D adsorption, while the Freundlich model provided a more accurate representation of the isotherms. 2,4-D maximum adsorption capacity stood at 131.39 mg/g at 303 K. The Hill statistical physics model elucidated that the adsorption primarily occurred via physisorption mechanisms, involving electrostatic attractions, π-π conjugation, and pore filling. This conclusion was further substantiated by post-adsorption characterization of the VI-BC. Thermodynamic analysis indicated that the interactions between VI-BC and 2,4-D were favorable, spontaneous, and exothermic. The calculated low energy of adsorption (1.255 kJ/mol) and ΔH° value (-20.49 kJ/mol) further supported physisorption as the dominant mechanism. In summary, this study underscores the significant potential of the newly developed biochar as a promising alternative material for efficiently removing the 2,4-D herbicide from polluted environments.


Asunto(s)
Dipterocarpaceae , Herbicidas , Contaminantes Químicos del Agua , Biomasa , Frutas , Carbón Orgánico/química , Termodinámica , Física , Adsorción , Cinética , Ácido 2,4-Diclorofenoxiacético , Concentración de Iones de Hidrógeno
15.
Indian Heart J ; 76(1): 27-30, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38070672

RESUMEN

BACKGROUND: Single chamber atrial pacemaker should be sufficient for patients with sinus node dysfunction (SND) with normal atrioventricular (AV) conduction. However, most patients undergo dual chamber pacemaker implantation because of concern of new onset AV block. The annual incidence of new AV block has been reported from 0.6 to 4.4 % in various studies. OBJECTIVES: Our aim is to assess mode survival in sinus node dysfunction with normal AV conduction patients implanted with AAIR. METHODS: Patients who underwent single chamber atrial pacemaker implantation for SND with normal AV conduction between January 2014 and December 2021 were followed up for pacemaker device change, new onset AV block, bundle branch block, atrial fibrillation (AF), lead complications, reoperation and mortality rate. RESULTS: A total of 113 patients underwent single chamber atrial pacemaker implantation for SND during the study period. Mean age was 55.6 ± 12.7 years. During a mean follow up of 48.7 ± 24.9 months, none of the patients required pacemaker device change to VVIR/DDDR. Nine patients underwent reoperation, 5 for lead dislodgment, 1 for high threshold, 1 for pocket site erosion and 3 for pulse generator change. None developed AV block or AF with slow ventricular rate. Only 4 patients developed AF (3 paroxysmal,1 permanent). There were 3 deaths during follow up and none were sudden deaths. CONCLUSION: Single chamber atrial pacing is an acceptable mode of pacing in patients with SND in developing countries. Development of AV conduction abnormalities is rare in this relatively younger population.


Asunto(s)
Fibrilación Atrial , Bloqueo Atrioventricular , Marcapaso Artificial , Humanos , Adulto , Persona de Mediana Edad , Anciano , Síndrome del Seno Enfermo/complicaciones , Bloqueo Atrioventricular/terapia , Estimulación Cardíaca Artificial/efectos adversos , Marcapaso Artificial/efectos adversos , Atrios Cardíacos , Fibrilación Atrial/cirugía , Fibrilación Atrial/epidemiología
16.
J Cosmet Dermatol ; 23(2): 563-575, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37909853

RESUMEN

BACKGROUND: Dandruff caused by Malassezia furfur is a prevailing fungal infection. Although ketoconazole (KTZ) is widely intended for anti-dandruff treatment, poor solubility, and epidermal permeability limits its use and the marketed KTZ shampoo adversely effects scalp and hair. OBJECTIVE: To prepare a novel shampoo loaded with KTZ-coated zinc oxide nanoparticles using green tea extract and evaluate its antifungal activity. METHODS: The KTZ-coated zinc oxide nanoparticles was prepared by green synthesis and was characterized by UV, FTIR, XRD, and the drug entrapment efficiency was investigated. The antifungal activity of the nanoparticles with respect to standard drug, KTZ was tested against Malassezia furfur. Further, a novel antidandruff shampoo was developed by incorporating the prepared nanoparticles into the shampoo base. RESULTS: The formation of KTZ-coated ZnO nanoparticles was confirmed by UV and FTIR analysis. XRD analysis confirmed the amorphous phase of KTZ in nanoparticles. The drug entrapment efficiency was found to be 91.84%. The prepared nanoparticles showed enhanced activity against Malassezia furfur compared to drug of choice, KTZ (1%). The evaluation of shampoo showed an ideal result. CONCLUSION: KTZ-coated ZnO nanoparticles loaded novel shampoo in comparison to marketed anti-dandruff shampoo could be an effective alternate for the treatment of dandruff.


Asunto(s)
Caspa , Preparaciones para el Cabello , Malassezia , Nanopartículas , Óxido de Zinc , Humanos , Cetoconazol , Antifúngicos/uso terapéutico , Caspa/tratamiento farmacológico , Óxido de Zinc/farmacología , Preparaciones para el Cabello/farmacología , Antioxidantes/farmacología ,
17.
Chemosphere ; 349: 140731, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38008295

RESUMEN

Hematite nanoparticles (AF-Fe2O3NPs) were prepared through a simple method utilizing Acacia falcata leaf extract in this investigation. The nanoparticles were extensively characterized to understand their specific properties. FESEM images revealed agglomerated surface morphology, while EDS confirmed the existence of elemental components, including Fe, O, and C. The mesoporous nature of AF-Fe2O3NPs with a pore diameter of 3.77 nm was determined through BET studies. XRD analysis indicated the crystallinity, with lattice parameters characteristic of hematite nanoparticles (a = 0.504 nm and c = 1.381 nm). Superparamagnetic property of the AF-Fe2O3NPs was affirmed from the saturation magnetization (2.98 emu/g) without any hysteresis. Subsequently, AF-Fe2O3NPs were used as adsorbent for the removal of Cr (VI) from aqueous solution. The experimental data were subjected to machine learning (ML) models, specifically ANN and ANFIS, to predict Cr (VI) removal. Both ML models exhibited excellent predictive capabilities, with high R2 values (>0.99) and low error indices such as MSE, RMSE, and MAE. Furthermore, comprehensive kinetic, isotherm, and thermodynamic studies were conducted to gain insights into the behavior and sorption mechanisms of Cr (VI). The Hill model, a statistical physics model, demonstrated an outstanding fit compared to conventional isotherms. It revealed a saturation adsorption potential of 12.91 mg/g at pH 2, 1.5 g/L dose, and a temperature of 30 °C, corroborating physisorption as the dominant mechanism. XPS results confirmed Cr (VI) reduction to Cr (III) through the appearance of specific peaks at 577.18 and 587.08 eV. Thermodynamic investigations established the endothermicity and spontaneity of the adsorption. In summary, the hematite nanoparticles synthesized in this study exhibit promising potential to remove Cr (VI) from aqueous streams, making them a viable option for water treatment applications.


Asunto(s)
Nanopartículas Magnéticas de Óxido de Hierro , Contaminantes Químicos del Agua , Adsorción , Termodinámica , Temperatura , Cinética , Cromo/química , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno
19.
Environ Res ; 238(Pt 1): 117124, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37716397

RESUMEN

This study focused on modeling the removal of one of the widely used agricultural herbicides known as 2,4-Dichlorophenoxyacetic acid (2,4-D) using polypyrrole-coated Fe2O3 nanoparticles (Fe2O3@PPy). The Fe2O3@PPy nanocomposite was synthesized by surface-coating the Tabebuia aurea leaf extract synthesized Fe2O3 nanoparticles with polypyrrole. After characterization, the adsorptive potential of the nanocomposite for removing 2,4-D from aqueous solution was examined. Central composite design (CCD) was employed for optimizing the adsorption, revealing an adsorption efficiency of 90.65% at a 2,4-D concentration of 12 ppm, a dosage of 3.8 g/L, an agitation speed of 150 rpm, and 196 min. Adsorption dataset fitted satisfactorily to Langmuir isotherm (R2: 0.984 & χ2: 0.054) and pseudo-second-order kinetics (R2: 0.929 & χ2: 0.013) whereas the exothermic and spontaneous nature were confirmed via the thermodynamic study. The predictive models, including adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), and response surface methodology (RSM), demonstrated good precision for the prediction of 2,4-D adsorption, with respective R2 of 0.9719, 0.9604, and 0.9528. Nevertheless, statistical analysis supported ANFIS as the better forecasting tool, while RSM was the least effective. The maximum adsorption capacity of 2,4-D onto the Fe2O3@PPy nanocomposite was 7.29 mg/g, significantly higher than a few reported values. Therefore, the Fe2O3@PPy nanocomposite could serve as a competent adsorbent to remove 2,4-D herbicide from aqueous streams.


Asunto(s)
Herbicidas , Nanocompuestos , Contaminantes Químicos del Agua , Herbicidas/análisis , Polímeros , Contaminantes Químicos del Agua/análisis , Pirroles/análisis , Termodinámica , Adsorción , Agua , Fenoxiacetatos , Ácido 2,4-Diclorofenoxiacético , Fenómenos Magnéticos , Cinética , Concentración de Iones de Hidrógeno
20.
Pacing Clin Electrophysiol ; 46(8): 840-847, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37477545

RESUMEN

BACKGROUND: In patients undergoing cardiac resynchronization therapy using left bundle branch area pacing (LBBP-CRT), the addition of a coronary sinus lead, that is, Left bundle optimized CRT (LOT-CRT) might confer additional benefits. OBJECTIVES: To compare the electrocardiographic characteristics between LBBP-CRT and LOT-CRT MATERIALS AND METHODS: Patients with non-ischemic cardiomyopathy (NICMP) and left bundle branch block (LBBB) with left ventricular ejection fraction <35% who underwent implantation of an atrial lead, a left bundle lead, and a coronary sinus lead were included in this prospective study. Digital 12-lead electrocardiograms were recorded in three pacing modes-AAI, DDD with pacing from the LBB lead (LBBP-CRT), and DDD with pacing from both left bundle and coronary sinus leads (LOT-CRT). QRS duration (QRSd), QRS area, QT interval, and T peak-T end (TpTe) intervals were compared. RESULTS: Among 24 patients, QRSd reduced from 167 ± 21.2 ms to 134.5 ± 23.6 ms with LBBP-CRT (p < .001) and 129.5 ± 18.6 ms with LOT-CRT (p < .001) without a significant difference between LBBP-CRT and LOT-CRT (p = .15). Patients with QRS duration with LBBP-CRT > 131 ms showed a significant reduction in QRSd with LOT-CRT (p = .03). QT interval was reduced with both modes of CRT. LOT-CRT was associated with a greater reduction in QRS area (p = .001), TpTe interval (p = .03), and TpTe/QT ratio (p = .013) compared to LBBP-CRT. CONCLUSIONS: In patients with NICMP and LBBB, there was no significant difference in QRSd with LOT-CRT compared to LBBP-CRT. However, in patients with QRSd > 131 ms after LBBP-CRT, LOT-CRT resulted in a significantly narrower QRS.


Asunto(s)
Terapia de Resincronización Cardíaca , Humanos , Terapia de Resincronización Cardíaca/métodos , Volumen Sistólico , Estudios Prospectivos , Función Ventricular Izquierda , Resultado del Tratamiento , Electrocardiografía/métodos , Bloqueo de Rama , Fascículo Atrioventricular , Estimulación Cardíaca Artificial/métodos
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