pH dependent synthesis and characterization of bismuth molybdate nanostructure for photocatalysis degradation of organic pollutants.

Bismuth molybdate (Bi2MoO6) nanostructures has attracted many researches as an advanced photocalysts for the organic contaminants. In this paper, bismuth molybdate Bi2MoO6 nanoparticles were synthesized using a simple hydrothermal method at varied pH (2, 4, 6, 8, and 10) for 15 h at 180 °C. The results reveal the variation pH precursor solutions have a significant impact on the morphology, phase formations, and photocatalytic activity of samples. The synthesized samples at low pH level were characterized by FESEM analysis revealing Bi2MoO6 nanoplates have formed while gradually convert to Bi2MoO6 spherical nanoparticle at high PH level as shown in energy dispersive X-ray spectroscopy (DES) peaks. The X-ray diffraction patterns reveal characteristic peaks corresponding to mixed phases of Bi2MoO6 and cubic Bi4MoO9 at high pH value. The optical absorption study exhibit Bi2MoO6 nanoplates absorbed visible light with blue shift when compared to the cubic Bi4MoO9 structures. Moreover, the photocatalytic activity results revealed that nanoplates in pH = 4 sample has excellent photocatalytic activity for degradation of rhodamine (RhB), methylene orange (MO), and phenol under visible-light irradiation (λ > 400 nm) as well as exhibit the photodegradation 90% of phenol within 300 min.

Phenotypic variability in chorea-acanthocytosis associated with novel VPS13A mutations.

OBJECTIVE: To perform a comprehensive characterization of a cohort of patients with chorea-acanthocytosis (ChAc) in Sweden. METHODS: Clinical assessments, targeted genetic studies, neuroimaging with MRI, [18F]-fluorodeoxyglucose (FDG) PET, and dopamine transporter with 123I FP-CIT (DaTscan) SPECT. One patient underwent magnetic resonance spectroscopy (MRS). RESULTS: Four patients living in Sweden but with different ethnical backgrounds were included. Their clinical features were variable. Biallelic VPS13A mutations were confirmed in all patients, including 3 novel mutations. All tested patients had either low or absent chorein levels. One patient had progressive caudate atrophy. Investigation using FDG-PET revealed severe bilateral striatal hypometabolism, and DaTscan SPECT displayed presynaptic dopaminergic deficiency in 3 patients. MRS demonstrated reduced N-acetylaspartate/creatine (Cr) ratio and mild elevation of both choline/Cr and combined glutamate and glutamine/Cr in the striatum in 1 case. One patient died during sleep, and another was treated with deep brain stimulation, which transiently attenuated feeding dystonia but not his gait disorder or chorea. CONCLUSIONS: Larger longitudinal neuroimaging studies with different modalities, particularly MRS, are needed to determine their potential role as biomarkers for ChAc.