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1.
Environ Res ; 237(Pt 1): 116919, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37597826

RESUMEN

Environmentally benign synthesis of nanocomposite, a pivotal facet of nanotechnology, and gaining prominence due to the increasing demand for facile, sustainable, and safe synthesis methods. The present research reports an facile/cost-effective method for the preparation of carbon dots (CDs) and carbon dot silver nanocomposites ( CD@AgNCs) via a hydrothermal treatment of peanut shells. The well-dispersed and spherical CDs with an average diameter of 5-6 nm were obtained and further employed for the preparation of CD@AgNCs. The formation of CD@AgNCs. was confirmed by optical and microscopic studies and ared shift in the λmax from 277 nm (CDs) to 450 nm (CD@AgNCs) with a size range of 30-40 nm was observed. The synthesized CD@AgNCs exhibit excellent catalytic potency for the reduction of 4-nitrophenol to 4-aminophenol, and also displaying a unique interaction and sensing ability towards heavy metal ions (Hg2+), causing a pronounced change in color from reddish-brown to transparent with limit of detection (LOD) of 23.47 ppm. Also, the prepared composite exhibit efficient antimicrobial potential against gram-negative (Escherichia coli) bacteria. Consequently, this study delves into a unified effective remediation platform with the integration of catalysis, sensing, and antimicrobial potentials.

2.
World J Surg ; 47(6): 1348-1357, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36811667

RESUMEN

BACKGROUND: The ward round is an integral part of everyday surgical practice. It is a complex clinical activity that requires both sound clinical management and communication skills. This study reports the results of a consensus-building exercise on the common aspects of the general surgical ward rounds. METHODS: The consensus-building committee involving a range of stakeholders from 16 United Kingdom (UK) National Health Service trusts took part in this consensus exercise. The members discussed and suggested a series of statements concerning surgical ward round. An agreement of ≥ 70% among members was regarded as a consensus. RESULTS: Thirty-two members voted on 60 statements. There was a consensus on fifty-nine statements after the first round of voting, and one statement was modified before it reached consensus in the second round. The statements covered nine sections: a preparation phase, team allocation, multidisciplinary approach to the ward round, structure of the round, teaching considerations, confidentiality and privacy, documentation, post-round arrangements, and weekend round. There was a consensus on spending time to prepare for the round, a consultant-led round, involvement of the nursing staff, an MDT round at the beginning and end of the week, a minimum of 5 min allocated to each patient, utilisation of a round checklist, afternoon virtual round, and a clear handover and plan for the weekend. CONCLUSION: The consensus committee achieved agreement on several aspects concerning the surgical ward rounds in the UK NHS. This should help improve the care of surgical patients in the UK.


Asunto(s)
Medicina Estatal , Humanos , Consenso , Técnica Delphi , Reino Unido
3.
Molecules ; 28(3)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36770827

RESUMEN

TiO2 thin films were deposited on quartz substrates by metal-organic chemical vapor deposition (MOCVD) at temperatures of 250, 350, and 450 °C. X-ray diffraction (XRD) data revealed the production of a pure anatase phase, a decrease in crystallite size, and a textural change as deposition temperature increased. Atomic force microscopy (AFM) was used to study the morphological properties and confirm XRD results. UV-Vis.-NIR spectroscopy was used to investigate the optical properties of the samples. The effect of deposition temperature on wettability was investigated using contact angle measurements. Sunlight photocatalytic properties increased with the increase in deposition temperature for methyl orange and methylene blue. Films were post-annealed at 500 °C for 2 h. The effect of annealing on all the above-mentioned properties was explored. The kinetic analysis demonstrated superb agreement with the kinetic pseudo-first-order model. The rate of photocatalytic degradation of MB was ~8, 13, and 12 times that of MO using 250, 350, and 450 °C deposited films, respectively. Photodegradation was found to depend on the specific surface area, type of pollutant, and annealing temperature.

4.
J Virol ; 94(3)2020 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-31694960

RESUMEN

The aryl hydrocarbon receptor (AhR) is a cytoplasmic receptor/transcription factor that modulates several cellular and immunological processes following activation by pathogen-associated stimuli, though its role during virus infection is largely unknown. Here, we show that AhR is activated in cells infected with mouse hepatitis virus (MHV), a coronavirus (CoV), and contributes to the upregulation of downstream effector TCDD-inducible poly(ADP-ribose) polymerase (TiPARP) during infection. Knockdown of TiPARP reduced viral replication and increased interferon expression, suggesting that TiPARP functions in a proviral manner during MHV infection. We also show that MHV replication induced the expression of other genes known to be downstream of AhR in macrophages and dendritic cells and in livers of infected mice. Further, we found that chemically inhibiting or activating AhR reciprocally modulated the expression levels of cytokines induced by infection, specifically, interleukin 1ß (IL-1ß), IL-10, and tumor necrosis factor alpha (TNF-α), consistent with a role for AhR activation in the host response to MHV infection. Furthermore, while indoleamine 2,3-dioxygenase (IDO1) drives AhR activation in other settings, MHV infection induced equal expression of downstream genes in wild-type (WT) and IDO1-/- macrophages, suggesting an alternative pathway of AhR activation. In summary, we show that coronaviruses elicit AhR activation by an IDO1-independent pathway, contributing to upregulation of downstream effectors, including the proviral factor TiPARP, and to modulation of cytokine gene expression, and we identify a previously unappreciated role for AhR signaling in CoV pathogenesis.IMPORTANCE Coronaviruses are a family of positive-sense RNA viruses with human and agricultural significance. Characterizing the mechanisms by which coronavirus infection dictates pathogenesis or counters the host immune response would provide targets for the development of therapeutics. Here, we show that the aryl hydrocarbon receptor (AhR) is activated in cells infected with a prototypic coronavirus, mouse hepatitis virus (MHV), resulting in the expression of several effector genes. AhR is important for modulation of the host immune response to MHV and plays a role in the expression of TiPARP, which we show is required for maximal viral replication. Taken together, our findings highlight a previously unidentified role for AhR in regulating coronavirus replication and the immune response to the virus.


Asunto(s)
Citocinas/metabolismo , Regulación Enzimológica de la Expresión Génica , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Virus de la Hepatitis Murina/fisiología , Poli(ADP-Ribosa) Polimerasas/biosíntesis , Provirus/fisiología , Receptores de Hidrocarburo de Aril/metabolismo , Replicación Viral/fisiología , Animales , Citocinas/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Ratones , Ratones Noqueados , Poli(ADP-Ribosa) Polimerasas/genética , Receptores de Hidrocarburo de Aril/genética , Transducción de Señal
5.
World J Urol ; 39(11): 4215-4219, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34091741

RESUMEN

PURPOSE: Transurethral resection of the prostate (TURP) can achieve highly satisfying symptomatic and functional outcomes but the loss of antegrade ejaculation represents a major reason for the avoidance of surgical treatment to preserve normal ejaculation and paternity. We present a novel technique to duplicate both bladder neck sparing and supramontanal sparing with resection of apical tissues to improve voiding and antegrade ejaculation. METHODS: A prospective study done from June 2018 to June 2020 on 60 consecutive male patients with normal sexual activity diagnosed with benign prostatic enlargement. These patients were randomized into two groups; 30 patients in each group. Group 1 underwent bladder neck and supramontanal sparing ejaculatory preserving transurethral bipolar resection of prostate (ep-TUBRP) and Group 2 underwent classic transurethral bipolar resection of prostate (c-TUBRP). All patients were evaluated pre- and postoperatively (after 3 months) using IPSS, Qmax and by IIEF-5. RESULTS: In both groups, there were significant improvements 3 months postoperative in Qmax [7.97 mL/s to 18.47 mL/s (group A) and 7.8 to 20.7 mL/s (group B)] and in micturition symptoms according to reductions in IPSS score [24 to 7.5 (group A) and 25 to 8.5 (group B)]. IIEF-5 score improved significantly from a mean of 12.9 to 18.6 (group A) and from 11.6 to 16.4 (group B). Antegrade ejaculation reported in 80% of patients in group A and 27% in group B which was significant (p < 0.001). Postoperative period did not reveal acute urinary retention, stress urinary incontinence, or serious adverse events. CONCLUSIONS: On short-term results, bladder neck and supramontanal ejaculation preserving transurethral bipolar resection of the prostate is superior to classic TURP in preservation of forward ejaculation with comparable efficacy in micturition parameters.


Asunto(s)
Eyaculación , Enfermedades de los Genitales Masculinos/prevención & control , Tratamientos Conservadores del Órgano/métodos , Complicaciones Posoperatorias/prevención & control , Resección Transuretral de la Próstata/métodos , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Vejiga Urinaria
6.
Sensors (Basel) ; 21(7)2021 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-33800565

RESUMEN

Oil leaks onto water surfaces from big tankers, ships, and pipeline cracks cause considerable damage and harm to the marine environment. Synthetic Aperture Radar (SAR) images provide an approximate representation for target scenes, including sea and land surfaces, ships, oil spills, and look-alikes. Detection and segmentation of oil spills from SAR images are crucial to aid in leak cleanups and protecting the environment. This paper introduces a two-stage deep-learning framework for the identification of oil spill occurrences based on a highly unbalanced dataset. The first stage classifies patches based on the percentage of oil spill pixels using a novel 23-layer Convolutional Neural Network. In contrast, the second stage performs semantic segmentation using a five-stage U-Net structure. The generalized Dice loss is minimized to account for the reduced oil spill representation in the patches. The results of this study are very promising and provide a comparable improved precision and Dice score compared to related work.

7.
Appl Psychophysiol Biofeedback ; 46(2): 161-173, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33877491

RESUMEN

Research suggest that in autism spectrum disorder (ASD) a disturbance in the coordinated interactions of neurons within local networks gives rise to abnormal patterns of brainwave activity in the gamma bandwidth. Low frequency transcranial magnetic stimulation (TMS) over the dorsolateral prefrontal cortex (DLPFC) has been proven to normalize gamma oscillation abnormalities, executive functions, and repetitive behaviors in high functioning ASD individuals. In this study, gamma frequency oscillations in response to a visual classification task (Kanizsa figures) were analyzed and compared in 19 ASD (ADI-R diagnosed, 14.2 ± 3.61 years old, 5 girls) and 19 (14.8 ± 3.67 years old, 5 girls) age/gender matched neurotypical individuals. The ASD group was treated with low frequency TMS (1.0 Hz, 90% motor threshold, 18 weekly sessions) targeting the DLPFC. In autistic subjects, as compared to neurotypicals, significant differences in event-related gamma oscillations were evident in amplitude (higher) pre-TMS. In addition, recordings after TMS treatment in our autistic subjects revealed a significant reduction in the time period to reach peak amplitude and an increase in the decay phase (settling time). The use of a novel metric for gamma oscillations. i.e., envelope analysis, and measurements of its ringing decay allowed us to characterize the impedance of the originating neuronal circuit. The ringing decay or dampening of gamma oscillations is dependent on the inhibitory tone generated by networks of interneurons. The results suggest that the ringing decay of gamma oscillations may provide a biomarker reflective of the excitatory/inhibitory balance of the cortex and a putative outcome measure for interventions in autism.


Asunto(s)
Trastorno del Espectro Autista , Estimulación Magnética Transcraneal , Adolescente , Trastorno del Espectro Autista/terapia , Niño , Función Ejecutiva , Femenino , Humanos , Modalidades de Fisioterapia , Corteza Prefrontal
8.
J Pediatr Gastroenterol Nutr ; 71(1): e12-e15, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32141997

RESUMEN

BACKGROUND: Anorectal malformations (ARMs) are a group of congenital malformations affecting the lower gastrointestinal, urogenital, and/or gynecological systems. They occur in approximately 1 in 5000 live births, with a slight male predominance. ARMs can appear in isolation or in association with other anomalies. The literature contains little information about the characteristics of ARMs in United States Hispanic populations. METHODS: An institutional review board-approved chart review was conducted in all patients with ARMs seen at a single institution in El Paso, Texas, from January 2012 to December 2015. Data regarding demographics, types of ARMs, associated syndromes, and long-term complications were recorded using the Krickenbeck classification system. RESULTS: Of the 37 patients included in the study, 20 were boys and 17 were girls. The most common ARMs were rectoperineal fistula (46%), rectourethral fistula, and cloacal malformation. Constipation was the most common long-term complication, especially in patients with recto-perineal fistula. CONCLUSION: Children in the Borderland community may have a higher percentage of recto-perineal fistula than previously reported. Postoperative complications in Hispanic children with ARM were comparable to those reported in other populations.


Asunto(s)
Malformaciones Anorrectales , Canal Anal , Niño , Femenino , Humanos , Masculino , México/epidemiología , Recto , Texas/epidemiología , Estados Unidos/epidemiología
9.
BMC Anesthesiol ; 19(1): 242, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31881971

RESUMEN

BACKGROUND: Intradialytic hypotension is a serious complication during renal replacement therapy in critically ill patients. Early prediction of intradialytic hypotension could allow adequate prophylactic measures. In this study we evaluated the ability of peripheral perfusion index (PPI) and heart rate variability (HRV) to predict intradialytic hypotension. METHODS: A prospective observational study included 36 critically ill patients with acute kidney injury during their first session of intermittent hemodialysis. In addition to basic vital signs, PPI was measured using Radical-7 (Masimo) device. Electrical cardiometry (ICON) device was used for measuring cardiac output, systemic vascular resistance, and HRV. All hemodynamic values were recorded at the following time points: 30 min before the hemodialysis session, 15 min before the start of hemodialysis session, every 5 min during the session, and 15 min after the conclusion of the session. The ability of all variables to predict intradialytic hypotension was assessed through area under receiver operating characteristic (AUROC) curve calculation. RESULTS: Twenty-three patients (64%) had intradialytic hypotension. Patients with pulmonary oedema showed higher risk for development of intradialytic hypotension {Odds ratio (95% CI): 13.75(1.4-136)}. Each of baseline HRV, and baseline PPI showed good predictive properties for intradialytic hypotension {AUROC (95% CI): 0.761(0.59-0.88)}, and 0.721(0.547-0.857)} respectively. CONCLUSIONS: Each of low PPI, low HRV, and the presence of pulmonary oedema are good predictors of intradialytic hypotension.


Asunto(s)
Lesión Renal Aguda/terapia , Frecuencia Cardíaca/fisiología , Hipotensión/etiología , Diálisis Renal/métodos , Adulto , Enfermedad Crítica , Femenino , Hemodinámica/fisiología , Humanos , Hipotensión/epidemiología , Masculino , Persona de Mediana Edad , Índice de Perfusión , Estudios Prospectivos , Edema Pulmonar/epidemiología
10.
Hum Biol ; 90(4): 301-310, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31714696

RESUMEN

The sella turcica has gained importance as a stable bony landmark in cephalometric studies. This study explored the changes that accompany postnatal ontogeny of the sella turcica until full development and verified its contribution in age estimation and sexual assignment among Egyptians. Six selected measurements of the sella turcica of 215 Egyptian patients were assessed using multidetector computed tomography. The patients represented different ages and were referred to the Diagnostic and Interventional Radiological Department, Faculty of Medicine, Alexandria University. The gathered data were then subjected to statistical analysis, including correlation and regression analysis. The measurements of the sella showed a strong correlation with age. Three selected measurements demonstrated significant sexual dimorphism: sella width and anterior and median height in subjects 20-25 years old. Six regression equations were derived. The accuracy achieved by the combined parameters in the younger group (<25 years old) was higher than that in the older individuals. This study provides useful tools in the determination of age and sex in both forensic and bioarcheological disciplines. However, further studies concerning the shape are strongly suggested.


Asunto(s)
Arqueología/métodos , Cefalometría , Medicina Legal/métodos , Tomografía Computarizada Multidetector , Silla Turca/diagnóstico por imagen , Silla Turca/crecimiento & desarrollo , Adulto , Factores de Edad , Egipto , Femenino , Humanos , Masculino , Análisis de Regresión , Factores Sexuales , Adulto Joven
11.
Ecotoxicol Environ Saf ; 162: 261-271, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-29990739

RESUMEN

Natural zeolite heulandite/polyaniline composite (Hu/PANI) was synthesized for the first time as catalyst support for nickel oxide photocatalyst (Hu/PANI@Ni2O3). The structural, chemical, morphological, textural and optical properties were investigated using different techniques. The synthetic Ni2O3 crystals showed well developed flaky habits with diameter range 200-400 nm and length range 1-4 µm. The estimated band gap energies of Hu/PANI composite and Hu/PANI@Ni2O3 composite are 1.8 eV and 1.46 eV, respectively, which are remarkably smaller than the recorded value for pure nickel oxide. The photocatalytic properties of Hu/PANI@Ni2O3 composite for efficient degradation of safranin-T dye were evaluated under sunlight as a function of irradiation time, initial dye concentration, catalyst mass, solution pH, and the catalyst stability. Hu/PANI@Ni2O3 composite exhibits amazing photocatalytic degradation efficiency for safranin dye, whereas 80%, 98%, and ~ 100% of 5 mg/l dye were removed after only 1 min of solar irradiation using 0.025, 0.03, and 0.035 g of Hu/PANI@Ni2O3, respectively. The higher concentrations of the dye (10-50 mg/L) can be fully removed within minutes by increasing the solution pH or using higher doses from the Hu/PANI@Ni2O3 catalyst. The removal percentage achieved the maximum value at the alkaline conditions. Also, the Hu/PANI@Ni2O3 displayed high stability and remain 84.5% of the initial photocatalytic efficiency after 5 runs. Additionally, the composite can be used effectively in the removal of different types of dyes and mixed dyes within the same time intervals. Thus, loading of nickel oxide onto hybrid Hu/PANI composite as a catalyst support achieved amazing photocatalytic degradation capacity.


Asunto(s)
Compuestos de Anilina/efectos de la radiación , Colorantes/química , Níquel/efectos de la radiación , Fenazinas/química , Luz Solar , Contaminantes Químicos del Agua/química , Zeolitas/efectos de la radiación , Compuestos de Anilina/química , Catálisis , Níquel/química , Fotólisis , Zeolitas/química
12.
Ecotoxicol Environ Saf ; 157: 358-368, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29631091

RESUMEN

Spongy Ni/Fe carbonate - fluorapatite was synthesized from natural phosphorite enriched with iron impurities. The morphological, chemical and structural features of the product were estimated using several techniques as XRD, SEM, EDX, and FT-IR. It exhibits spongy structure of nano and micro-pores. The average crystallite size is about 8.27 nm. The suitability of the product for considerable decontamination of Zn2+, Co2+, and Cu2+, ions from water was studied based on several reacting parameters. The equilibrium was attained after 240 min for Zn2+ and Co2+ ions while the adsorption equilibrium of Cu2+ reached after 120 min. The adsorption data for the selected metals was represented well by a pseudo-second-order model which revealed chemisorption uptake. The equilibrium studies were appraised based on traditional models and two advanced models were designed according to the statistical physical theories. The adsorption results highly fitted with Langmuir model followed rather than the other models. This indicated a monolayer adsorption for the metal ions by spongy Ni/Fe carbonate - fluorapatite. The estimated qmax values are 149.25 mg/g, 106.4 mg/g and 147.5 mg/g for the uptake of Zn2+, Co2+, and Cu2+, respectively. Based on monolayer models of one energy and two energies, the number of receptor adsorption sites, number of adsorbed metal ions per active site, the average number of sites which occupied by ions, mono layer adsorption quantity and the adsorption quantity after total saturation were calculated for the first time for such materials.


Asunto(s)
Apatitas/química , Carbonatos/química , Cobalto/química , Cobre/química , Purificación del Agua , Zinc/química , Adsorción , Cobalto/aislamiento & purificación , Cobre/aislamiento & purificación , Concentración de Iones de Hidrógeno , Hierro/química , Modelos Teóricos , Nanoporos/ultraestructura , Níquel/química , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Difracción de Rayos X , Zinc/aislamiento & purificación
13.
J Environ Manage ; 204(Pt 1): 189-199, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28881328

RESUMEN

MCM-48 mesoporous silica was successfully synthesized from silica gel extracted from rice husk ash and loaded by nickel oxide (Ni2O3). The resulted composite was characterized using X-ray diffraction, scanning electron microscope, and UV-vis spectrophotometer. The role of MCM-48 as catalyst support in enhancing the photocatalytic properties of nickel oxide was evaluated through the photocatalytic degradation of Congo red dye under visible light source. MCM-48 as catalyst support for Ni2O3 shows considerable enhancement in the adsorption capacity by 17% and 29% higher than the adsorption capacity of MCM-48 and Ni2O3, respectively. Additionally, the photocatalytic degradation percentage increased by about 64% relative to the degradation percentage using Ni2O3 as a single component. The adsorption mechanism of MCM-48/Ni2O3 is chemisorption process of multilayer form. The using of MCM-48 as catalyst support for Ni2O3 enhanced the adsorption capacity and the photocatalytic degradation through increasing the surface area and prevents the nickel oxide particles from agglomeration. This was done through fixing nickel oxide particles throughout the porous structure which providing more exposed active adsorption sites and active photocatalyst sites for the incident photons. Based on the obtained results, supporting of nickel oxide particles onto MCM-48 are promising active centers for the degradation of Congo red dye molecules.


Asunto(s)
Níquel/química , Oryza/química , Gel de Sílice/química , Dióxido de Silicio/síntesis química , Adsorción , Catálisis , Rojo Congo , Luz , Porosidad , Dióxido de Silicio/química , Difracción de Rayos X
14.
Korean J Parasitol ; 54(4): 477-84, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27658600

RESUMEN

There is renewed interest in natural products as a starting point for discovery of drugs for schistosomiasis. Recent studies have shown that phytol reveals interesting in vivo and in vitro antischistosomal properties against Schistosoma mansoni adult worms. Here, we report the in vitro antischistosomal activity of phytol against Schistosoma haematobium juvenile and adult worms and alterations on the tegumental surface of the worms by means of scanning electron microscopy. The assay, which was carried out with 6 concentrations (25, 50, 75, 100, 125, and 150 µg/ml) of phytol, has shown a promising activity in a dose and time-dependent manner. There was a significant decline in the motility of the worms and a mortality rate of 100% was found at 48 hr after they had been exposed to phytol in the concentration of 150 µg/ml. Male worms were more susceptible. On the ultrastructural level, phytol also induced tegumental peeling, disintegration of tubercles and spines in addition to morphological disfiguring of the oral and ventral suckers. This report provides the first evidence that phytol is able to kill S. haematobium of different ages, and emphasizes that it is a promising natural product that could be used for development of a new schistosomicidal agent.


Asunto(s)
Antihelmínticos/farmacología , Integumento Común , Fitol/farmacología , Schistosoma haematobium/efectos de los fármacos , Schistosoma haematobium/ultraestructura , Animales , Relación Dosis-Respuesta a Droga , Femenino , Locomoción/efectos de los fármacos , Masculino , Mesocricetus , Microscopía Electrónica de Rastreo , Schistosoma haematobium/fisiología , Caracoles , Análisis de Supervivencia , Factores de Tiempo
15.
RSC Adv ; 14(10): 6776-6792, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38405070

RESUMEN

This study investigated the electrochemical behavior of NiCu, NiCu/GO, and NiCu/rGO nanocomposites designed by combining a modified Hummers' method and hydrothermal technique. The prepared nanocomposites are tested as electrocatalysts in direct alcohol oxidation fuel cells (DAFCs) to identify the role of GO and rGO as catalyst supports for the enhancement of the NiCu composite performance. The production of the NiCu/GO and NiCu/rGO composites was demonstrated by FTIR spectroscopy, EDX, and SEM analyses. In DAFCs experiments, NiCu/rGO has better catalytic activity than pure NiCu and NiCu/GO composites, whereas the use of rGO and GO as supports enhances the performance of NiCu by 468.2% and 377.7% in methanol and 255.6% and 105.9% in ethanol, respectively. The higher performance was caused by the increased density of active dots and the combined electronic effects in the designed catalysts. The stabilities of the catalysts and charge carriers' dynamics are studied using chronoamperometry and electrochemical impedance spectroscopy.

16.
Sci Rep ; 14(1): 15227, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956146

RESUMEN

Methylene blue dye, being toxic, carcinogenic and non-biodegradable, poses a serious threat for human health and environmental safety. The effective and time-saving removal of such industrial dye necessitates the use of innovative technologies such as silver nanoparticle-based catalysis. Utilizing a pulsed Nd:YAG laser operating at the second harmonic generation of 532 nm with 2.6 J energy per pulse and 10 ns pulse duration, Ag nanoparticles were synthesized via an eco-friendly method with sodium dodecyl sulphate (SDS) as a capping agent. Different exposure times (15, 30, and 45 min) resulted in varying nanoparticle sizes. Characterization was achieved through UV-Vis absorption spectroscopy, scanning electron microscopy (SEM) imaging, and energy dispersive X-ray (EDX). Lorentzian fitting was used to model nanoparticle size, aligning well with SEM results. Mie's theory was applied to evaluate the absorption, scattering, and extinction cross-sectional area spectra. EDX revealed increasing Ag and carbon content with exposure time. The SDS-caped AgNPs nanoparticles were tested as catalyst for methylene blue degradation, achieving up to 92.5% removal in just 12 min with a rate constant of 0.2626 min-1, suggesting efficient and time-saving catalyst compared to previously reported Ag-based nanocatalysts.

17.
J Mol Model ; 30(6): 190, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809306

RESUMEN

CONTEXT: For the advancement in fields of organic and perovskite solar cells, various techniques of structural alterations are being employed on previously reported chromophores. In this study, the end-capped engineering is carried out on DBT-4F (R) by modifying terminal acceptors to improve optoelectronic and photovoltaic attributes. Seven molecules (AD1-AD7) are modeled using different push-pull acceptors. DFT/B3LYP/6-31G along with its time-dependent approach (TD-DFT) are on a payroll to investigate ground state geometries, absorption maxima (λmax), energy gap (Eg), excitation energy (Ex), internal reorganization energy, light harvesting efficiency (LHE), dielectric constant, open circuit voltage (VOC), fill factor (FF), etc. of OSCs. AD1 displayed the lowest band gap (1.76 eV), highest λmax (876 nm), lowest Ex (1.41 eV), and lowest binding energy (0.21 eV). Among various calculated parameters, all of the sketched molecules demonstrated greater dielectric constant when compared to R. The highest dielectric constant was exhibited by AD3 (56.26). AD5 exhibited maximum LHE (0.9980). Lower reorganization energies demonstrated improved charge mobility. AD5 and AD7 (1.63 and 1.68 eV) have higher values of VOC than R (1.51 eV). All novel molecules having outperforming attributes will be better candidates to enhance the efficacy of OSCs for future use. METHODS: Precisely, a DFT and TD-DFT analysis on all of the proposed organic molecules were conducted, using the functional MPW1PW91 at 6-31G (d,p) basis set to examine their optoelectronic aspects, additionally the solvent-state computations were studied with a TD-SCF simulation. For all these simulations, Guassian 09 and GuassView 5.0 were employed. Moreover, the Origin 6.0, Multiwfn 3.8, and PyMOlyze 1.1 software were utilized for the visual depiction of the graphs of absorption, TDM, and DOS, respectively of the studied molecules. A number of crucial aspects such as FMOs, bandgaps, light-harvesting efficiency, electrostatic potential, dipole moment, ionization potential, open-circuit voltage, fill factor, binding energy, interaction coefficient, chemical hardness-softness, and electrophilicity index were also investigated for the studied molecules.

18.
Foods ; 13(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38928886

RESUMEN

Chlorella vulgaris (C.V) is known for its high protein and nutrient contents and has been touted as a potential functional ingredient in food products. For this study, beef burgers were formulated with varying levels of Chlorella vulgaris fortification (0%, 0.5%, 1%, and 1.5% by weight). The nutritional composition, including proximate analysis and mineral content, was determined for each treatment group. The quality characteristics evaluated included thiobarbituric acid (TBA), total volatile base nitrogen (TVBN), pH, and total acidity. The study included extracting the active substances from Chlorella vulgaris using three solvents, 50% ethanol, 95% ethanol, and water, to evaluate the effect on the antimicrobial and antioxidant activity. The results showed that the water extract had the highest total phenolic content (183.5 mg gallic acid equivalent per gram) and the highest flavonoid content (54 mg quercetin per gram). The aqueous extract had the highest content of total antioxidants, followed by the 95% ethanol and 50% ethanol extracts. Meanwhile, the 50% ethanol extract showed the best antimicrobial activity, while the aqueous extract had less of an effect on Gram-positive bacteria and no effect on E. coli. For the burger treatments, at the end of the storage period, it was observed that the microbial load of the treatments decreased compared to the control, and there was a high stability in the total volatile base nitrogen (TVBN) values for the treatments compared to the control, reaching a value of 22.4 at month 5, which is well above the acceptable limit, indicating spoilage. The pH values were higher for all of the treatments, with a lower total acidity for all of the treatments compared to the control. In conclusion, utilizing Chlorella vulgaris algae as a natural preservative to extend the freshness of burgers is a sustainable and innovative approach to food preservation. By harnessing the power of this green superfood, we not only enhance the shelf life of our food products but also contribute to a healthier and more environmentally friendly food industry.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124082, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38479227

RESUMEN

Heavy metals have been widely applied in industry, agriculture, and other fields because of their outstanding physics and chemistry properties. They are non-degradable even at low concentrations, causing irreversible harm to the human and other organisms. Therefore, it is of great significance to develop high accuracy and sensitivity as well as stable techniques for their detection. Raman scattering spectroscopy and atomic absorption spectrophotometer (AAS) were used parallelly to detect heavy metal ions such as Hg, Cd, and Pb of different concentrations in fish samples. The concentration of the heavy metals is varied from 5 ppb to 5 ppm. Despite the satisfactory recoveries of AAS, their drawbacks are imperative for an alternative technique. In Raman scattering spectroscopy, the intensities and areas of the characteristic peaks are increased with increasing the concentration of the heavy metals. For Hg concentration ≥ 1 ppm, a slight shift is observed in the peak position. The obtained values of peak intensity and peak area are modeled according to Elvoich, Pseudo-first order, Pseudo-second order, and asymptotic1 exponential model. The best modeling was obtained using the Elovich model followed by the asymptotic1 exponential model. The introduced Raman spectroscopy-based approach for on-site detection of trace heavy metal pollution in fish samples is rapid, low-cost, and simple to implement, increasing its visibility in food safety and industrial applications.


Asunto(s)
Mercurio , Metales Pesados , Animales , Humanos , Espectrometría Raman , Metales Pesados/análisis , Mercurio/análisis , Peces , Contaminación Ambiental , Cadmio/análisis , Monitoreo del Ambiente
20.
J Mol Graph Model ; 129: 108722, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38377792

RESUMEN

Modification of terminal acceptors of non-fullerene organic solar cell molecule with different terminal acceptors can help in screening of molecules to develop organic photovoltaic cells with improved performance. Thus, in this work, seven new molecules with an unfused core have been designed and thoroughly investigated. DFT/TD-DFT simulations were performed on studied molecules to explore the ground and excited state characteristics. UV-Visible analysis revealed the red shift in the absorption spectrum (reaching 781 nm) owing to their smaller energy gap up to 1.94 eV. Furthermore, transition density matrix analysis demonstrated that peripheral acceptors extract the electron density from the core effectively. The effectiveness of our investigated molecules as materials for high-performing organic photovoltaic cells has been shown by an examination of their electron and hole mobilities for fast charge transfer. When combined with PTB7-Th, all molecules displayed high open circuit voltage. XP5 molecule exhibited highest open circuit voltage (1.70 eV) and lowest energy loss of 0.30 eV. All designed molecules exhibit the improved aforementioned parameters, which shows that these molecules can be used to develop competent solar devices in future.


Asunto(s)
Electrones
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