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1.
Molecules ; 26(9)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067122

RESUMO

Organic materials development, especially in terms of nonlinear optical (NLO) performance, has become progressively more significant owing to their rising and promising applications in potential photonic devices. Organic moieties such as carbazole and quinoline play a vital role in charge transfer applications in optoelectronics. This study reports and characterizes the donor-acceptor-donor-π-acceptor (D-A-D-π-A) configured novel designed compounds, namely, Q3D1-Q3D3, Q4D1-Q1D2, and Q5D1. We further analyze the structure-property relationship between the quinoline-carbazole compounds for which density functional theory (DFT) and time-dependent DFT (TDDFT) calculations were performed at the B3LYP/6-311G(d,p) level to obtain the optimized geometries, natural bonding orbital (NBO), NLO analysis, electronic properties, and absorption spectra of all mentioned compounds. The computed values of λmax, 364, 360, and 361 nm for Q3, Q4, and Q5 show good agreement of their experimental values: 349, 347, and 323 nm, respectively. The designed compounds (Q3D1-Q5D1) exhibited a smaller energy gap with a maximum redshift than the reference molecules (Q3-Q5), which govern their promising NLO behavior. The NBO evaluation revealed that the extended hyperconjugation stabilizes these systems and caused a promising NLO response. The dipole polarizabilities and hyperpolarizability (ß) values of Q3D1-Q3D3, Q4D1-Q1D2, and Q5D1 exceed those of the reference Q3, Q4, and Q5 molecules. These data suggest that the NLO active compounds, Q3D1-Q3D3, Q4D1-Q1D2, and Q5D1, may find their place in future hi-tech optical devices.

2.
Pharmaceutics ; 15(5)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37242799

RESUMO

With the growing demand for the development of intranasal (IN) products, such as nasal vaccines, which has been especially highlighted during the COVID-19 pandemic, the lack of novel technologies to accurately test the safety and effectiveness of IN products in vitro so that they can be delivered promptly to the market is critically acknowledged. There have been attempts to manufacture anatomically relevant 3D replicas of the human nasal cavity for in vitro IN drug tests, and a couple of organ-on-chip (OoC) models, which mimic some key features of the nasal mucosa, have been proposed. However, these models are still in their infancy, and have not completely recapitulated the critical characteristics of the human nasal mucosa, including its biological interactions with other organs, to provide a reliable platform for preclinical IN drug tests. While the promising potential of OoCs for drug testing and development is being extensively investigated in recent research, the applicability of this technology for IN drug tests has barely been explored. This review aims to highlight the importance of using OoC models for in vitro IN drug tests and their potential applications in IN drug development by covering the background information on the wide usage of IN drugs and their common side effects where some classical examples of each area are pointed out. Specifically, this review focuses on the major challenges of developing advanced OoC technology and discusses the need to mimic the physiological and anatomical features of the nasal cavity and nasal mucosa, the performance of relevant drug safety assays, as well as the fabrication and operational aspects, with the ultimate goal to highlight the much-needed consensus, to converge the effort of the research community in this area of work.

3.
ACS Omega ; 8(22): 19341-19350, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37305309

RESUMO

Chitosan (Cs)-based silver-doped titanium dioxide (Cs-AgTiO2) films were synthesized intending their end-use application in food packaging. AgTiO2 NPs were successfully prepared by using electrochemical synthesis. Cs-AgTiO2 films were synthesized by using the solution casting technique. Various advanced instrumental techniques such as scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) were used for the characterization of Cs-AgTiO2 films. Intending their food packaging applications, samples were further investigated to obtain varied biological results including antibacterial (Escherichia coli), antifungal (Candida albicans), and nematicidal activities. Ampicillin (E. coli) and fluconazole (C. albicans) were used as models. FT-IR and XRD confirm the structural modification of Cs. IR peak shifting was observed, which confirmed that AgTiO2 interacted with chitosan via amide I and amide II groups. This confirmed the stability of the filler in the polymer matrix. SEM also confirmed the successful incorporation of AgTiO2 NPs. Cs-AgTiO2 (3%) shows excellent antibacterial (16.51 ± 2.10 µg/mL) and antifungal (15.67 ± 2.14 µg/mL) activities. Nematicidal assays were also done, and Caenorhabditis elegans (C. elegans) was used as a model organism. Cs-AgTiO2 NPs (3%) exhibited excellent nematicidal potential (64.20 ± 1.23 µg/mL), which could make these films a suitable novel material to control nematode spread in food.

4.
Curr Probl Cardiol ; 48(6): 101127, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35124076

RESUMO

In patient undergoing transcatheter aortic valve implantation (TAVI), stroke remains a potentially devastating complication associated with significant morbidity, and mortality. To reduce the risk of stroke, cerebral protection devices (CPD) were developed to prevent debris from embolizing to the brain during TAVI. We performed a systematic review and meta-analysis to determine the safety and efficacy of CPD in TAVI. The MEDLINE (PubMed, Ovid) and Cochrane databases were queried with various combinations of medical subject headings to identify relevant articles. Statistical analysis was performed using a random-effects model to calculate unadjusted odds ratio (OR), including subgroup analyses based on follow-up duration, study design, and type of CPD. Using a pooled analysis, CPD was associated with a significant reduction in major adverse cardiovascular events MACE (OR 0.75, 95% CI 0.70-0.81, P < 0.01), mortality (OR 0.65, 95% CI 0.58-0.74, P < 0.01) and stroke (OR 0.84, 95% CI 0.76-0.93, P < 0.01) in patients undergoing TAVI. Similarly, on MRI volume per lesion were lower for patients with CPD use. No significant difference was observed in acute kidney injury (OR 0.75, 95% CI 0.42-1.37, P = 0.68), bleeding (OR 0.92, 95% CI 0.71-1.20, P = 0.55) or vascular complications (OR 0.90, 95% CI 0.62-1.31, P = 0.6) for patients undergoing TAVI with CPD. In conclusion, CPD device use in TAVI is associated with a reduction of MACE, mortality, and stroke compared with patients undergoing TAVI without CPD. However, the significant reduction in mortality is driven mainly by observational studies.


Assuntos
Estenose da Valva Aórtica , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Estenose da Valva Aórtica/cirurgia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Encéfalo , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Resultado do Tratamento , Fatores de Risco
5.
J Am Heart Assoc ; 11(11): e024746, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35621233

RESUMO

Background There is a paucity of data on the feasibility of same-day discharge (SDD) following transcatheter aortic valve implantation (TAVI) at a national level. Methods and Results This study used data from the Nationwide Readmission Database from the fourth quarter of 2015 through 2019 and identified patients undergoing TAVI using the claim code 02RF3. A total of 158 591 weighted hospitalizations for TAVI were included in the analysis. Of the patients undergoing TAVI, 961 (0.6%) experienced SDD. Non-SDDs included 65 814 (41.5%) patients who underwent TAVI who were discharged the next day, and 91 816 (57.9%) discharged on the second or third day. The 30-day readmission rate for SDD after TAVI was similar to non-SDD TAVI (9.8% versus 8.9%, P=0.31). The cumulative incidence of 30-day readmissions for SDD was higher compared with next-day discharge (log-rank P=0.01) but comparable to second- or third-day discharge (log-rank P=0.66). At 30 days, no differences were observed in major or minor vascular complications, heart failure, or ischemic stroke for SDD compared with non-SDD. Acute kidney injury, pacemaker implantation, and bleeding complications were lower with SDD. Predictors associated with SDD included age <85 years, male sex, and prior pacemaker placement, whereas left bundle-branch block, right bundle-branch block, second-degree heart block, heart failure, prior percutaneous coronary intervention, and atrial fibrillation were negatively associated with SDD. Conclusions SDD following TAVI is associated with similar 30-day readmission and complication rates compared with non-SDD. Further prospective studies are needed to assess the safety and feasibility of SDD after TAVI.


Assuntos
Estenose da Valva Aórtica , Insuficiência Cardíaca , Substituição da Valva Aórtica Transcateter , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Bloqueio de Ramo/epidemiologia , Insuficiência Cardíaca/complicações , Humanos , Masculino , Alta do Paciente , Readmissão do Paciente , Estudos Retrospectivos , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento
6.
Bioresour Technol ; 321: 124427, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33264745

RESUMO

Anaerobic digestion of animal manure show a maximum of ca. 50% conversion of volatile solids due to recalcitrance of lignin and crystalline cellulose under anaerobic conditions. The aim of this study is to evaluate different pretreatments on anaerobic digestion of manure fibers after anaerobic digestion. Physical, chemical, thermal, and thermal combined with alkaline pretreatments using sodium hydroxide were tested on manure fiber fraction separated out after anaerobic digestion of cow manure. The anaerobic digestion after pretreatment along with untreated controls were done in semi-continuous anaerobic bioreactors. All pretreatments showed positive effect and the highest increase in VS conversion (42.4%) and methane yield (ca. 127%) was found for 3% NaOH pretreated sample at 180 °C. Composition analysis showed that cellulose, hemicellulose and lignin in digested manure fibers were optimally reduced by 24.8, 29.1 and 9.5% respectively during pretreatment and 76.5% of cellulose and 84.9% of hemicellulose was converted to methane during AD.


Assuntos
Biocombustíveis , Esterco , Anaerobiose , Animais , Lignina/metabolismo , Metano
7.
Bioresour Technol ; 298: 122537, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31838240

RESUMO

This study examine ways to make biorefinery lignin accessible for anaerobic digestion. The raw material was the residue after removing carbohydrates by Wet Explosion pretreatment at 190 °C and 7.5% O2 followed by enzymatic hydrolysis. The residual solid was mainly composed of lignin and was the raw material for a second WEx pretreatment operated at 220 °C with 4% oxygen and variable concentrations of NaOH (0-2%). Lignin B was the residue after pretreated without NaOH, Lignin C was pretreated at 1% NaOH, and Lignin E at 2% NaOH. Anaerobic digestion was carried out on all lignin fractions (Lignin A, B, C and E) at thermophilic conditions (52 °C) by mixing 70% of each lignin fractions with 30% clarified manure. The results showed that the lignin samples were demethoxylated as part of the biodegradation and that the highest severity pretreatment (with oxygen and 2% NaOH) resulted in the highest methane yield.


Assuntos
Explosões , Lignina , Anaerobiose , Hidrólise , Metano
8.
Polymers (Basel) ; 12(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963778

RESUMO

In this study, activated carbon microsphere (SLACM) was prepared from powdered sodium lignosulfonate (SL) and polystyrene by the Mannich reaction and ZnCl2 activation, which can be used to remove Cr(VI) from the aqueous solution without adding any binder. The SLACM was characterized and the batch experiments were conducted under different initial pH values, initial concentrations, contact time durations and temperatures to investigate the adsorption performance of Cr(VI) onto SLACM. The results indicated that the SLACM surface area and average pore size were 769.37 m2/g and 2.46 nm (the mesoporous material), respectively. It was found that the reduced initial pH value, the increased temperature and initial Cr(VI) concentration were beneficial to Cr(VI) adsorption. The maximum adsorption capacity of Cr(VI) on SLACM was 227.7 mg/g at an initial pH value of 2 and the temperature of 40 °C. The adsorption of SLACM for Cr(VI) mainly occurred during the initial stages of the adsorption process. The adsorption kinetic and isotherm experimental data were thoroughly described by Elovich and Langmuir models, respectively. SL could be considered as a potential raw material for the production of activated carbon, which had a considerable potential for the Cr(VI) removal from wastewater.

9.
RSC Adv ; 10(35): 20595-20607, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35517764

RESUMO

The geometric, thermodynamic and electronic properties of Pd-graphene nanocomposites are comprehensively studied through quantum mechanical methods. Geometries of these clusters are optimized with the well-calibrated Minnesota functional M06-2X. The adsorption energies calculated at the M06-2X/LANL2DZ level show better agreement with those calculated from MP2/ANO-RCC-VDZP. Two different representative models for graphene, coronene and hexabenzocoronene, are used. The adsorption energies analysis reveals that the interaction energies increase with the size of the adsorbed cluster. However, for Pd n /hexabenzocoronene, the interaction energies show a sudden drop at Pd8/hexabenzocoronene. The difference in behavior between the interaction energies of Pd n /hexabenzocoronene and Pd n /coronene is attributed to the edge effect present in coronene. The electronic properties, including highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), Fermi level, molecular electrostatic potential (MEP), dipole moment, vertical ionization potential (VIP), vertical electron affinity (VEA), chemical hardness (η), softness (S) and chemical potential (µ) are studied. The VIP and VEA reveal that Pd n /coronene clusters are stable in nature with the least reactivity. The HOMO-LUMO energy gaps are reduced with the increase in cluster size. The electronic properties show irregular trends, where the most favorable electronic properties are obtained for Pd7/coronene and Pd10/coronene.

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