A Review of the Common Neurodegenerative Disorders: Current Therapeutic Approaches and the Potential Role of Nanotherapeutics

Neurodegenerative disorders are primarily characterized by neuron loss. The most common neurodegenerative disorders include Alzheimer’s and Parkinson’s disease. Although there are several medicines currently approved for managing neurodegenerative disorders, a large majority of them only help with associated symptoms. This lack of pathogenesis-targeting therapies is primarily due to the restrictive effects of the blood–brain barrier (BBB), which keeps close to 99% of all “foreign substances” out of the brain. Since their discovery, nanoparticles have been successfully used for targeted delivery into many organs, including the brain. This review briefly describes the pathophysiology of Alzheimer’s, Parkinson’s disease, and amyotrophic lateral sclerosis, and their current management approaches. We then highlight the major challenges of brain-drug delivery, followed by the role of nanotherapeutics for the diagnosis and treatment of various neurological disorders.     

Effect of sulfur-doped graphene quantum dots incorporation on morphological,optical and electron transport properties of CH3NH3PbBr3 perovskite thin films

Organic–inorganic hybrid perovskite materials have recently attracted extensive interest to develop next-generation high efficiency optoelectronic devices. However, in many of these devices, perovskite thin films are the key source of photogenerated electron and hole pairs. Therefore, a strategy for the preparation of high-quality perovskite thin films with a fewer number of traps at surfaces and grain boundaries is highly desired. In this work, sulfur-doped graphene quantum dots (S-GQDs) were synthesized and incorporated in the CH₃NH₃PbBr₃ perovskite precursor to prepare S-GQDs incorporated perovskite thin films. The as-prepared thin films were systematically characterized using X-ray diffractometer, field emission scanning electron microscope, UV–Vis and fluorescence spectrophotometer to investigate the effect of different amounts of S-GQDs on their morphology, optical absorbance and electron transfer properties. The experimental findings revealed that multiple surface functional groups, quantum confinement and desirable electronic conductivity in S-GQDs help passivate the perovskite surface by reducing the surface and grain boundary traps. Interestingly, the incorporation of S-GQDs increased the light absorption of CH₃NH₃PbBr₃ along with faster electron transfer across their interfaces. Hence, this strategy of S-GQDs incorporation presents a versatile and novel way to prepare highly efficient perovskite thin films for developing next-generation solar cells, light emitting diodes and other optoelectronic devices.

     

The effects of culture condition on the growth property and docosahexaenoic acid production from Thraustochytrium aureum ATCC 34304

The effect of the composition of artificial sea water (ASW) medium on the growth properties and docosahexaenoic acid (DHA) production from Thraustochytrium aureum ATCC 34304 was investigated. A maximum dry cell weight (DCW) of 3.71 g/l was obtained when the NaCl and MgSO₄ concentration in the ASW media were 15 and 0 g/l, respectively. The maximum initial specific growth (ISG) rate of 0.16 was attained at 7.5 g/l NaCl and 18 g/l MgSO₄, while the minimum ISG rate (0.02) was obtained at 5.0 g/l NaCl and 4.5 g/l MgSO₄. The least doubling time required for biomass production was 4.3 h at 7.5 g/l NaCl and different MgSO₄ concentrations. A maximum of 7.9 g/l DCW was obtained on the fourth day of cultivation at 30 g/l glucose and 2.5 g/l (each) yeast extract (YE) and peptone. The DHA content in the lipids was significantly affected by the concentration of glucose and nitrogen sources (YE and peptone) in the ASW medium. At the lowest glucose (10 g/l) and YE/peptone (0.5 g/l) concentration and highest glucose (30 g/l) and YE/peptone (2.5 g/l) concentration, the DHA content was 34.725 and 40.33%, respectively, relative to total lipid content. However, the DHA content in the lipid was not affected by the NaCl and MgSO₄ concentration. At the lowest NaCl (2.5 g/l) and MgSO₄ (4.5 g/l) concentration and highest NaCl (60 g/l) and MgSO₄ (18 g/l) concentration the DHA content was 39.62 and 38.48%, respectively. The maximum DHA content in the lipid was 49.01% after four days of cultivation when 7.5 g/l NaCl and 4.5 g/l MgSO₄ were in the ASW medium. The growth properties of T. aureum ATCC 34304 for biomass production and DHA yield in the lipid content were found to be affected by NaCl and glucose concentration.     

New IBS coatings boost performance of petawatt laser mirrors

Simply put, the performance of a laser is just as high as the quality of its optics. Latest advances in petawatt laser technology have stimulated the development of large surface area, dielectrically coated mirrors to guide these demanding ultrashort pulse laser beams. We describe major achievements during the development and fabrication of ion beam sputtered 440 × 290 × 75 mm³ beam transport mirrors for the HAPLS laser at ELI Beam-lines. A laser damage threshold greater than 0.9 J/cm² was measured.