Galdieria maxima is a polyextremophilic alga capable of diverse metabolic processes. Ammonia is widely used in culture media typical of laboratory growth. Recent reports that this species can grow on wastes promote the concept that G. maxima might have biotechnological utility. Accordingly, there is a need to know the range of pH levels that can support G. maxima growth in a given nitrogen source. Here, we examined the combined effect of pH and nitrate/ammonium source on the growth and long-term response of the photochemical process to a pH gradient in different G. maxima strains. All were able to use differing nitrogen sources, despite both the growth rate and photochemical activity were significantly affected by the combination with the pH. All strains acidified the NH4+-medium (pH<3); only G. maxima IPPAS P507 showed reduced capacity in lowering the pH from 6.5. pH was a limiting factor in nitrate uptake at pH≥6.5; noteworthy, at pH 5 on nitrate G. maxima ACUF551 showed a good growth performance, despite the alkalization of the medium.

(Background) Cognitive deficits related to frontotemporal dysfunction are common in Amyotrophic Lateral Sclerosis (ALS). Visuospatial deficits, related to posterior cerebral regions, are often underestimated in ALS, though they play a crucial role in attending daily living activities. Our pilot study aims at assessing visuospatial abilities using a domain-specific tool in ALS patients compared to healthy controls (HC). (Methods) Twenty-three patients with early ALS and 23 age- and education-matched HC underwent the Battery for Visuospatial Abilities (BVA), including visuo-perceptual and visuo-representational subtests. (Results) When compared to HC, ALS scored worse in 2 out of 4 visuo-perceptual subtests (i.e., Line Length Judgment and Line Orientation Judgment) and 1 out of 4 visuo-representational tasks (i.e., Hidden Figure Identification, HFI) (p &lt;0.01). No correlations arose between ALS clinical features and BVA performance. More than 80% of the ALS cohort obtained abnormal scores in HFI subtest. (Conclusions) Our findings revealed that ALS scored worse (compared to HC) on selective tests tapping “perceptual” and “representational” visuospatial abilities, since early stages of disease. In clinical practice, our findings highlight the need of multi-domain neuropsychological assessment, for monitoring disease course and properly organizing care management of patients with ALS.