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The present study, La0.7Sr0.3MO3 (M = Mn-, Co-, and Fe-), perovskite, has successfully been synthesized via co-precipitation and sol-gel auto-combustion. XRD, SEM, and EDX characterized the prepared samples. XRD and SEM showed that the as-prepared La0.7Sr0.3MnO3 and La0.7Sr0.3CoO3 have multiphase. La0.7Sr0.3FeO3, in comparison, is nanosized, has a single-phase perovskite, and has a rather homogenous particle size distribution. Additionally, EDX mapping analysis shows that all pieces are distributed uniformly. According to X-ray diffractometer results, all calcined powders contain 100% LSF, more than 15% perovskite phase of LSC, 47% LSM, and other secondary phases, such as cobalt oxide. AÙt room temperature and magnetic field of ± 20 kG, La0.7Sr0.3MnO3 exhibited weak ferromagnetic behavior in a low magnetic field, whereas diamagnetic behavior was seen in a high magnetic field. La0.7Sr0.3FeO3 samples behave as strong ferromagnetic. On the contrary, the photodegradation of La0.7Sr0.3MnO3 is 99% compared to 75% and 91% for other samples under UVC lights of wavelength = 254 nm. The degradation rate for La0.7Sr0.3MnO3 is 0.179 higher, about 3.25 and 2.23, than the other samples. A La0.7Sr0.3MnO3 nanocomposite performs as a photocatalyst to enhance the efficiency of methylene blue photodegradation. This study boosts good UVC photocatalysts with high efficiency for different kinds of dyes. Hence, the catalyst possessed high stability and efficiency for continuous wastewater treatment.
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Nanopartículas , Nanoestruturas , Nanoestruturas/química , Nanopartículas/química , Magnetismo , Campos MagnéticosRESUMO
Plasmodium sporozoites associated with the midgut and in the hemolymph of mosquitoes differ from sporozoites in the secretory cavities and ducts of the insects' salivary glands in their transcriptome, proteome, motility, and infectivity. Using an ex vivo Anopheles stephensi salivary gland culture system incorporating simple microfluidics and transgenic Plasmodium berghei with the fluorescent protein gene mCherry under the transcriptional control of the Pbuis4 promoter whose expression served as a proxy for parasite maturation, we observed rapid parasite maturation in the absence of salivary gland invasion. While in vivo Pbuis4::mCherry expression was only detectable in sporozoites within the salivary glands (mature parasites) as expected, the simple exposure of P. berghei sporozoites to dissected salivary glands led to rapid parasite maturation as indicated by mCherry expression. These results suggest that previous efforts to develop ex vivo and in vitro systems for investigating sporozoite interactions with mosquito salivary glands have likely been unsuccessful in part because the maturation of sporozoites leads to a loss in the ability to invade salivary glands.
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Anopheles , Animais , Plasmodium berghei/genética , Plasmodium berghei/metabolismo , Esporozoítos , Regulação da Expressão Gênica , Glândulas SalivaresRESUMO
In this paper, we discuss the preparation of Li-doped ZnO nanostructures through combustion and report on their structural, morphological, optical, and electrocatalysis properties. X-ray diffraction analyses show that the samples have a structure crystallized into the usual hexagonal wurtzite ZnO structure according to the P63mc space group. The scanning electron microscope images conceal all samples' nanosphere bundles and aggregates. The reflectance spectra analysis showed that the direct bandgap values varied from 3.273 eV (for pure ZnO, i.e., ZnL1) to 3.256 eV (for high Li-doped ZnO). The measured capacitance concerning frequency has estimated the variation of dielectric constant, dielectric loss, and AC conductivity against AC electric field frequency. The dielectric constant variations and AC conductivity are analyzed and discussed by well-known models such as Koop's phenomenological theory and Jonscher's law. The Raman spectra have been recorded and examined for the prepared samples. Rhodamine B was electro-catalytically degraded in all prepared samples, with the fastest time for ZnL5 being 3 min.
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In this proposed study, erbium (Er3+)-doped ZnO nanocomposites were prepared through the effective, basic, and green combustion method. The significant effects of Er dopants on the structural, morphological features, dielectric, and optical behaviors of the pure ZnO matrix as well as Er2O3-ZnO nanostructured materials were investigated applying X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transformation infrared (FT-IR) spectroscopy, and UV-Vis spectrophotometer techniques. These results showed that the synthesized Er2O3-ZnO nanocomposites are well polycrystalline. The Er2O3-ZnO nanocomposites are almost uniformly distributed on the surface morphologies. Furthermore, UV-Vis diffuse reflectance spectroscopy, AC electrical conductivity, and dielectric properties' current-voltage characteristics were utilized to examine the influence of erbium doping on the optical properties, energy bandgaps of the proposed Er2O3-ZnO nanostructured powder. The tested nano-samples were applied for the visible light photodegradation of p-chlorophenol(4-CP) and p-nitrophenol (4-NP). The Er-doped ZnO ratio affects the photocatalytic activity of the ZnO matrix. This current research substantiated that more than 99.5% of 4-CP and 4-NP were photodegraded through 30 min of irradiation. Four times, the Er:ZnO nanocatalysts were used and still displayed an efficiency of more than 96.5% for 4-CP and 4-NP degradations in the specified period of 30 min. The as-prepared Er2O3-ZnO nanostructures are considered novel potential candidates in broad nano-applications from visible photocatalytic degradation of waste pollutants to the electronic varistor devices.
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Purificação da Água , Óxido de Zinco , Catálise , Cerâmica , Eletrônica , Luz , Espectroscopia de Infravermelho com Transformada de Fourier , Óxido de Zinco/químicaRESUMO
A lanthanum oxide (La2O3)-ZnO nanostructured material was synthesized in the proposed study with different La2O3 concentrations, 0.001 g to 5 g (named So to S7), using the combustion method. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transformation infrared spectroscopy (FT-IR) were utilized for investigating the structure, morphology, and spectral studies of the La2O3- ZnO nanomaterials, respectively. The results obtained from previous techniques support ZnO's growth from crystalline to nanoparticles' fine structure by changing the concentrations of lanthanum oxide (La2O3) dopants in the host matrix. The percentage of ZnO doped with La- influences the ZnO photocatalytic activity. SEM analysis confirmed the grain size ranged between 81 and 138 nm. Furthermore, UV-Vis diffuse reflectance spectroscopy was performed to verify the effects of La2O3 dopants on the linear optical properties of the nano-composite oxides. There was a variation in the energy bandgaps of La2O3-ZnO nanocomposites, increasing the weight concentrations of lanthanum dopants. The AC electrical conductivity, dielectric properties, and current-voltage properties support the enactment of the electrical characteristics of the ZnO nanoparticles by adding La2O3. All the samples under investigation were used for photodegradation with Rhodamine B (RhB) and Methylene Blue (MB). In less than 30 min of visible light irradiation, S4 (0.5 g) La2O3-ZnO reached 99% of RhB and MB degradation activity. This study showed the best photocatalytic effect for RhB and MB degradation of 0.13 and 0.11 min-1 by 0.5 g La2O3-ZnO. Recycling was performed five times for the nanocatalysts that displayed up to 98 percent catalytic efficiency for RhB and MB degradation in 30 min. The prepared La2O3-ZnO nanostructured composites are considered novel candidates for various applications in biomedical and photocatalytic studies.
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The growth of the textile industry results in a massive accumulation of dyes on water. This enormous rise in pigments is the primary source of water pollution, affecting the aquatic lives and our ecosystem balance. This study aims to notify the fabrication of neodymium incorporated copper oxide (Nd2O3 doped CuO) nanoparticles by combustion method for effective degradation of dye, methylene blue (MB). X-ray diffraction (XRD), Field emission Scanning electron microscopy (FESEM), Zeta potential have been applied for characterization. Photocatalyst validity has been evaluated for methylene blue degradation (MB). Test conditions such as time of contact, H2O2, pH, and photo-Fenton have been modified to identify optimal degradation conditions. Noticeably, 7.5% Nd2O3 doped CuO nanoparticle demonstrated the highest photocatalytic efficiency, up to 90.8% in 80 min, with a 0.0227 min-1 degradation rate. However, the photocatalytic efficiency at pH 10 becomes 99% with a rate constant of 0.082 min-1. Cyclic experiments showed the Nd2O3 doped CuO nanoparticle's stability over repeated use. Scavenge hydroxyl radical species responsible for degradation using 7.5% Nd2O3 doped CuO nanoparticles have been investigated under visible irradiation.
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The incorporation of tungsten trioxide (WO3) by various concentrations of graphitic carbon nitride (g-C3N4) was successfully studied. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Diffused Reflectance UV-Vis techniques were applied to investigate morphological and microstructure analysis, diffused reflectance optical properties, and photocatalysis measurements of WO3/g-C3N4 photocatalyst composite organic compounds. The photocatalytic activity of incorporating WO3 into g-C3N4 composite organic compounds was evaluated by the photodegradation of both Methylene Blue (MB) dye and phenol under visible-light irradiation. Due to the high purity of the studied heterojunction composite series, no observed diffraction peaks appeared when incorporating WO3 into g-C3N4 composite organic compounds. The particle size of the prepared composite organic compound photocatalysts revealed no evident influence through the increase in WO3 atoms from the SEM characteristic. The direct and indirect bandgap were recorded for different mole ratios of WO3/g-C3N4, and indicated no apparent impact on bandgap energy with increasing WO3 content in the composite photocatalyst. The composite photocatalysts' properties better understand their photocatalytic activity degradations. The pseudo-first-order reaction constants (K) can be calculated by examining the kinetic photocatalytic activity.
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An efficient and environmentally friendly combustion technique was employed to produce ZnO nanopowders with different Eu concentrations (from 0.001 g to 5 g). The structural morphology of the Eu2O3-ZnO nanocomposites was examined using XRD, SEM, and infrared spectroscopy (FT-IR). In addition, UV-Vis diffuse reflectance spectroscopy was also used to investigate the effects of europium (Eu) dopant on the optical behaviors and energy bandgaps of nano-complex oxides. The photocatalytic degradation efficiency of phenol and methylene blue was investigated using all the prepared Eu2O3-ZnO nanostructured samples. Photocatalytic effectiveness increased when europium (Eu) doping ratios increased. After adding moderate Eu, more hydroxyl radicals were generated over ZnO. The best photocatalyst for phenol degradation was 1 percent Eu2O3-ZnO, while it was 0.5 percent Eu2O3-ZnO for methylene blue solutions. The obtained Eu2O3-doped ZnO nanostructured materials are considered innovative, promising candidates for a wide range of nano-applications, including biomedical and photocatalytic degradation of organic dyes and phenol.
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OBJECTIVES: Percutaneous patent ductus arteriosus (PDA) stenting is a therapeutic modality in patients with duct-dependent pulmonary circulation with reported success rates from 80-100%. The current study aims to assess the outcome and the indicators of success for PDA stenting in different ductal morphologies using various approaches. METHODS: A prospective cohort study from a single tertiary center presented from January 2018 to December 2019 that included 96 consecutive infants with ductal-dependent pulmonary circulation and palliated with PDA stenting. Patients were divided according to PDA origin into 4 groups: Group 1: PDA from proximal descending aorta, Group 2: from undersurface of aortic arch, Group 3: opposite the subclavian artery, Group 4: opposite the innominate/brachiocephalic artery. RESULTS: The median age of patients was 22 days and median weight was 3 kg. The procedure was successful in 78 patients (81.25%). PDA was tortuous in 70 out of 96 patients. Femoral artery was the preferred approach in Group 1 (63/67), while axillary artery access was preferred in the other groups (6/11 in Group 2, 11/17 in Group 3, 1/1 in Group 4, P <0.0001). The main cause of procedural failure was inadequate parked coronary wire inside one of the branch of pulmonary arteries (14 cases; 77.7%), while 2 cases (11.1%) were complicated by acute stent thrombosis, and another 2 cases with stent dislodgment. Other procedural complications comprised femoral artery thrombosis in 7 cases (7.2%). Patients with straight PDA, younger age at procedure and who had larger PDA at pulmonary end had higher odds for success (OR = 8.01, 2.94, 7.40, CI = 1.011-63.68, 0.960-0.99, 1.172-7.40,respectively, P = 0.048, 0.031,0.022 respectively). CONCLUSIONS: The approach for PDA stenting and hence the outcome is markedly determined by the PDA origin and morphology. Patients with straight PDA, younger age at procedure and those who had relatively larger PDA at the pulmonary end had better opportunity for successful procedure.
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Permeabilidade do Canal Arterial , Cateterismo Cardíaco/métodos , Permeabilidade do Canal Arterial/cirurgia , Humanos , Lactente , Estudos Prospectivos , Circulação Pulmonar , Estudos Retrospectivos , Stents , Resultado do TratamentoRESUMO
The pyrolysis of melamine was an effective one-pot method for preparing a nanostructured multifunctional photocatalytic based on core/shell g-C3N4@TiO2 heterojunction. Various techniques entirely characterized these materials: X-ray diffraction (XRD) proved to enhance the as-prepared materials' crystallinity through the variation of dislocation, strain, and crystallite size with TiO2 loading. The stacked layered/sheet-like with a smooth surface of the as-prepared samples have been shown via scanning electron microscopy (SEM). Diffuse reflectance spectroscopy (DRS) showed an apparent decrease in the energy bandgap for these nanocomposites with TiO2 loading. All the prepared materials were subjected to visible photocatalytic applications under the same conditions. The dye model (Methylene Blue, MB), and antibiotic model (Amoxicillin, AMO), was photodegraded using the as-prepared nanocomposites under visible light irradiation. In the recombination reduction among TiO2 and g-C3N4 interfaces, g-C3N4 has been effectively utilized as a matrix. Our findings proved that g-C3N4@TiO2 photocatalysts exhibited superior photocatalytic performance. CNT-5 of 2.58 eV bandgap had a higher activity of 99.7 in 50 min for MB and 100% in 20 min for AMO than the other represented photocatalysts in this work. The migration of photogenerated electrons from a g-C3N4 to TiO2 via heterojunction among them as g-C3N4 (1 0 1) removes the electrons accumulated on (1 0 1) of TiO2, improve the photodegradation efficiency. Therefore, the increase in photocatalytic reaction rates, recycling, and the sample's photostability can be considered the result of successful interactions among the TiO2 and g-C3N4 systems. The suggested photodegradation mechanism of MB and AMO was discussed in detail and compared with previously reported work. Therefore, the photodegradation rate of MB and AMO via CNT-5 composite is 6 and 3 times, respectively, higher than that of g-C3N4 under simulated solar irradiation. This research creates a new perspective on the production of nanocomposite materials in the area of treatment of pharmaceutical and dye contaminants.
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Preparações Farmacêuticas , Titânio , Catálise , FotóliseRESUMO
In this study, poly(methyl methacrylate) with different doping nano-cadmium sulfide (CdS/PMMA) is prepared and characterized. CdS/PMMA polymeric nanocomposite films were synthesized using solution casting methodology. SEM and XRD are used for structure analysis for the studied nanocomposite films. XRD revealed the amorphous domains of PMMA polymer, which increased with increasing CdS nanoparticle contents. SEM revealed the CdS dispersion within the PMMA matrix. CdS nanoparticles in the PMMA matrix are expected to be aggregated due to the casting technique. The optical energy gap is found to be decreased after the CdS addition. ε' and εⳠhave the same behavior with the applied frequency. Maxwell-Wagner interfacial polarization is the responsible factor for higher values of ε'-εⳠat the higher frequencies. Electrical conductivity behavior σAC tends to obtain a constant value at lower frequencies that approach from its DC conductivity values. After doping PMMA with nano-CdS, an exponential increase after a critical frequency value and the values of σAC was also increased. Besides, a significant reduction in laser energy power is identified by the reduction of the output power. CdS/PMMA can attenuate the laser power due to its nonlinear effect. CdS/PMMA nanocomposite can act as a photocatalyst to improve the performance of the photodegradation of Rhodamine B (RhB). Among the different CdS/PMMA nanocomposite films, 3.33 wt% CdS/PMMA demonstrates the highest efficiency in visible photocatalysis of Rhodamine B. CdS/PMMA can be utilized as multifunctional materials use like laser optical limiting to reduce the power of laser sources and as a photocatalyst membranes.