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Cranial nerve palsies can be presenting signs of intracranial aneurysms. There is a classic pairing between an aneurysmal vessel and adjacent nerves leading to cranial neuropathy. Isolated abducens nerve palsy can be a localizing sign of an unruptured vertebrobasilar circulation aneurysm. Aneurysms involving Anterior Inferior Cerebellar Artery (AICA) and Posterior Inferior Cerebellar Artery (PICA) have been reported to be associated with abducens nerve palsy. The symptoms in unruptured aneurysms are due to the mass effect on adjacent neurovascular structures. Most of the abducens nerve palsy resolves following microsurgical clipping. Here, we present a rare case of an unruptured Posterior Cerebral Artery (PCA) aneurysm presenting with abducens nerve palsy and diplopia associated with contralateral hemianopsia which markedly improved following endovascular coil embolization. [ABSTRACT FROM AUTHOR]

Bismuth-doped metal oxides exhibit favourable photocatalytic features when exposed to both sunlight and UV light. In this approach, Bi0/TiO2 and Bi+3/TiO2 photocatalysts were prepared and their structural and optical properties are analysed using various characterization techniques. These developed photocatalysts were further tested for the photocatalytic elimination of Nitrobenzene in UV light and sunlight and compared with the performance of bare TiO2. The catalyst Bi+3/TiO2 performed better in UV light with 72.31% degradation, and 4.74 × 10−6 mol.litre−1.min−1 initial rate of reaction. However, when exposed to sunlight, Bi0/TiO2 outperformed with 73.85% degradation, and 4.63 × 10−6 mol.min−1 initial rate of reaction. This significant increase in photocatalytic activity of Bi0/TiO2 under sunlight could be accredited to increased light harvesting and enhanced efficiency in charge carrier separation, both of which were made possible by bismuth-induced surface plasmon resonance. [ABSTRACT FROM AUTHOR]

BACKGROUND: Commercial TiO2 nanoparticles were subjected to modification through Bi and Zn metal doping. The resulting catalysts were comprehensively characterized, and their performance was then reviewed for removal of model pollutant nitrobenzene in water. RESULTS: Amidst the synthesized catalysts, the co‐doping of Bi/Zn (0.25:0.75 wt%) demonstrated the best photocatalytic degradation activity, achieving 95% degradation within 90 min of reaction time, with 2.99 × 10−2 min−1 rate constant value. The involvement of different radicals during the degradation process was elucidated by employing appropriate radical scavengers. Furthermore, the degradation results were investigated applying the first‐order kinetic model, leading to the determination of reaction rate constants and initial rates of the degradation process. CONCLUSION: An improved photocatalytic activity was observed with metal doping due to the synergistic effect of doped metals with commercial TiO2 and profound charge transfer among them. It was observed that performance was increased with temperature rise in the practical range of application, that is, 5–20 °C. This behavior was due to high rate of movement of charge carriers. Further, involvement and functioning of various radical species such as h+, OH− and O2− in nitrobenzene degradation were successfully established using appropriate radical scavengers. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Background: Cerebral computed tomography angiography (CTA) has revolutionized the diagnosis of neurovascular emergencies. Strategies to reduce radiation, a concern for cancer, involve tube voltage and current reduction but with increased noise and inferior image quality. Hence, the objective of the study was to evaluate the quality of images obtained through low-dose radiation and low-contrast volume CTA with an iterative reconstruction (IR) technique versus standard CTA without IR. Methods: This prospective trial involved 100 adults requiring cerebral CTA for cerebrovascular diseases. They were split into two groups: one with 120 kVp tube voltage and 80 mL contrast using filtered back projection, and the other with 80 kVp and 30 mL contrast with IR. Evaluation criteria included attenuation values, signal-to-noise ratio, contrast-to-noise ratio, and subjective assessments. Results: Compared to 120 kVp, 80 kVp showed higher vessel attenuation in the internal (272.91 ± 30.59 vs 405.52 ± 53.08; p <.001) and middle cerebral artery (247.55 ± 29.84 vs 372.55 ± 49.02; p <.001) regions. Brain parenchymal attenuation at the centrum semiovale was lower with 80 kVp (29.12 ± 1.87 vs 24.78 ± 2.94; p <.001), accompanied by higher noise. Signal-to-noise ratio (p <.001) and contrast-to-noise ratio (p <.05) were lower at 80 kVp. Image quality didn't significantly differ, and radiation exposure reduced significantly by 70% in the 80 kVp group, suggesting its diagnostic feasibility. Conclusions: The 80 kVp protocol for CTA of the cerebral vessels combined with lower contrast volume produces images with similar image quality with significant radiation effective dose and total iodine dose reduction. The 80 kVp protocol holds significant promise for replacing the standard 120 kVp protocol in cerebral CTA. [ABSTRACT FROM AUTHOR]

BACKGROUND: Semiconductor photocatalysts based on TiO2 nanoparticles were synthesized via the sol–gel method and subsequently modified using monometallic (Bi‐TiO2, Zn‐TiO2) and bimetallic (Bi/Zn‐TiO2) doping through the wet‐impregnation technique. The prepared photocatalysts underwent comprehensive characterization using X‐ray diffraction analysis, Fourier transform infrared spectroscopy, ultraviolet–visible diffuse‐reflectance spectroscopy, field emission scanning electron microscopy, photoluminescence, and thermal gravimetric analysis. The photocatalytic performance of these well‐characterized photocatalysts was assessed for the degradation of the model organic pollutant, nitrobenzene. RESULTS: Among the various doped TiO2 catalysts, Bi/Zn co‐doping at a ratio of 0.25:0.75 (w/w) exhibited the most remarkable synergistic effect, achieving approximately 82% degradation of a 50 ppm nitrobenzene solution within just 90 min of reaction time under ultraviolet light irradiation. The rate constant for this process was determined to be 1.79 × 10−2 min−1, suggesting a pseudo‐first‐order kinetics model. CONCLUSION: The successful co‐doping of Bi and Zn metals to TiO2 resulted in improved photocatalytic performance. The enhanced performance could be attributed to the improved charge transfer facilitated by the synergistic effect among doped metals and TiO2. This finding highlights the significance of bimetallic doping and its potential applications in improving the photocatalytic efficiency of TiO2 nanoparticles for environmental remediation. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Third generation photovoltaic dye-sensitized solar cells (DSSCs) are an area of interest due to their cost-effectiveness and better performance under diffuse light conditions. The design and development of effective photoanodes and their materials still play a significant role and can be explored. Metal doping in TiO2 semiconductor has been proven to be an effective way for charge separation. The synthesis of bismuth (Bi) doped TiO2 materials is attempted with different Bi doping quantities through wet impregnation for their utilization in DSSCs. The purpose of the Bi-doped TiO2 synthesis was to develop an efficient photoanode material with an enhanced charge separation capacity to be applied in DSSC, leading to high current density and overall device performance. The morphology and optical behaviour of synthesized materials were characterized by powder X-ray diffractometer (P-XRD), UV-visible spectrophotometry, field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), photoluminescence (PL), and thermogravimetric analysis (TGA). The synthesized materials were used to prepare absorption layers of photoanode in DSSCs in conjunction with a ruthenium-based dye (N719). The findings showed that the highest power conversion efficiency (PCE) of the Bi-doped TiO2-based DSSCs was measured 5.50% using 3% Bi doping to TiO2 (w/w), surpassing the 3.58% efficiency achieved by the TiO2-based DSSCs in similar conditions, with an enhancement of ~ 54% in PCE performance. The enhanced performance could be attributed to the incorporation of Bi to TiO2 which can help with electron transfer in the forward direction in DSSCs circuit by reducing electron–hole recombination. [ABSTRACT FROM AUTHOR]