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Background: This study compared rapid and slow intrathecal fentanyl injection followed by a slow injection of bupivacaine to estimate the duration of postoperative analgesia in lower-segment caesarean sections (LSCS). Methods: The study was performed on 60 parturient aged 18-35 years undergoing LSCS and was divided equally into two groups. Group A (Normal Sequential) received slow sequential intrathecal injections of fentanyl and hyperbaric bupivacaine and Group B (Rapid Sequential) received a rapid intrathecal injection of fentanyl followed by a slow injection of hyperbaric bupivacaine. We compared the duration of postoperative analgesia, time of onset of sensory and motor block attained, the highest level of sensory block attained, duration of motor block, Visual Analogue Scale (VAS) scores, spinal anaesthesia-related complications and haemodynamic parameters between both the groups. Results: The duration of postoperative analgesia was longer (P < 0.001) in group B (3.22 ± 0.66 hrs) as compared to group A (2.53 ± 0.41 hrs.) The onset of sensory block was faster (P < 0.001) in group B (1.01 ± 0.29 min) as compared to group A (1.32 ± 0.08 min). More patients in group B achieved higher levels of sensory blockade as compared to group A (5 patients in group A and 12 patients ofgroup B achieved a sensory block up to the T2 dermatome). VAS scores and the requirement of rescue analgesia were significantly lower (10 in group B and 19 in group A). Conclusion: Rapid sequential intrathecal injection of fentanyl and hyperbaric bupivacaine provided better anaesthesia and postoperative analgesia than the normal group. [ABSTRACT FROM AUTHOR]

Visible light-active nickel-based plasmonic photocatalysts provide a cost-effective alternative to noble metals. However, their rarity, fragility, and limited understanding pose challenges. This work presents a microwave-assisted organic synthesis of a Ni-NiO@Ni 2 CO 3 (OH) 2 core-shell@sheet plasmonic photocatalyst. By employing time and power dependent synthesis, this catalyst exhibits flexible Ni 2 CO 3 (OH) 2 nanosheets enveloping the Ni-NiO structure, surpassing the pristine Ni@NiO/NiCO 3 core-shell counterpart. Chemical reaction mechanisms suggest that irradiation of pristine Ni-NiO/NiCO 3 nano structures leads to breakage of amorphous NiCO 3 to Ni 2+ and CO 3 2- , which further, in the presence of water solvent, interacts with OH - ions leading to the formation of Ni(CO 3 )·Ni(OH) 2 . With enhanced light absorption and photocatalytic properties, the resulting core-shell@sheet photocatalyst demonstrates double the hydrogen evolution reaction yield (40 μmol g -1 h -1 ) compared to the pristine catalyst (20 μmol g -1 h -1 ). The enhanced H 2 yield is attributed to the flexible sheets, cross-dimensional photocatalyst structure, increased surface area for surface reactions, and higher H 2 activity of Ni 2 CO 3 (OH) 2 . This research showcases the potential of microwave-assisted synthesis in developing flexible nanosheets with superior solar water splitting performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Ni@NiO/NiCO 3 core-shell nanostructures have been investigated for surface plasmon driven photocatalytic solar H 2 generation without any co-catalyst. Huge variation in the photocatalytic activity has been observed in the pristine vs. post-vacuum annealed samples with the maximum H 2 yield (∼110 μmol g -1 h -1 ) for the vacuum annealed sample (N70-100/2 h) compared to ∼92 μmol g -1 h -1 for the pristine (N70) photocatalyst. Thorough structural (X-ray diffraction) and spectroscopic (X-ray photoelectron spectroscopy and transmission electron microscopy coupled electron energy loss spectroscopy) investigations reveal the core Ni nanoparticle decorated with the shell, a composite of crystalline NiO and amorphous NiCO 3 . Significant visible light absorption at ∼475 nm in the UV-vis region along with the absence of a peak/edge corresponding to NiO suggest the role of surface plasmons in the observed catalytic activity. As per the proposed mechanism, amorphous NiCO 3 in the shell has been suggested to serve as the dielectric medium/interface, which enhances the surface plasmon resonance and boosts the HER activity., Competing Interests: There are no conflict of interests to declare., (This journal is © The Royal Society of Chemistry.)

P25 comprising of mixed anatase and rutile phases is known to be highly photocatalytically active compared to the individual phases. Using a facile wet chemical method, we demonstrate a ternary nanocomposite consisting of Ni and Ag nanoparticles, decorated on the surface of XTiO 2 (X: P25, rutile (R)) as an efficient visible-light-driven photocatalyst. Contrary to the current perspective, RTiO 2 -based Ni-Ag-RTiO 2 shows the highest activity with the H 2 evolution rate of ∼86 μmol g -1 W -1 h -1 @535 nm. Together with quantitative assessment of active Ni, Ag and XTiO 2 in these ternary systems using high energy synchrotron X-ray diffraction, transmission electron microscopy coupled energy dispersive spectroscopy mapping evidences the metal to semiconductor contact via Ag. The robust photocatalytic activity is attributed to the improved visible light absorption, as noted by the observed band edge of ∼2.67 eV corroborating well with the occurrence of Ti 3+ in Ti 2p XPS. The effective charge separation due to intimate contact between Ni and RTiO 2 via Ag is further evidenced by the plasmon loss peak in Ag 3d XPS. Moreover, density functional theory calculations revealed enhanced adsorption of H 2 on Ti 8 O 16 clusters when both Ag and Ni are simultaneously present, owing to the hybridization of the metal atoms with d orbitals of Ti and p orbitals of O leading to enhanced bonding characteristics, as substantiated by the density of states. Additionally, the variation in the electronegativity in Bader charge analysis indicates the possibility of hydrogen evolution at the Ni sites, in agreement with the experimental observations., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)