Inhibition by ammonium at concentrations above 1000 mgN/L is known to harm the methanogenesis phase of anaerobic digestion. We anaerobically digested swine waste and achieved steady state COD-removal efficiency of around 52% with no fatty-acid or H[subscript 2] accumulation. As the anaerobic microbial community adapted to the gradual increase of total ammonia-N (NH[subscript 3]-N) from 890 ± 295 to 2040 ± 30 mg/L, the Bacterial and Archaeal communities became less diverse. Phylotypes most closely related to hydrogenotrophic Methanoculleus (36.4%) and Methanobrevibacter (11.6%), along with acetoclastic Methanosaeta (29.3%), became the most abundant Archaeal sequences during acclimation. This was accompanied by a sharp increase in the relative abundances of phylotypes most closely related to acetogens and fatty-acid producers (Clostridium, Coprococcus, and Sphaerochaeta) and syntrophic fatty-acid Bacteria (Syntrophomonas, Clostridium, Clostridiaceae species, and Cloacamonaceae species) that have metabolic capabilities for butyrate and propionate fermentation, as well as for reverse acetogenesis. Our results provide evidence countering a prevailing theory that acetoclastic methanogens are selectively inhibited when the total ammonia-N concentration is greater than ~1000 mgN/L. Instead, acetoclastic and hydrogenotrophic methanogens coexisted in the presence of total ammonia-N of ~2000 mgN/L by establishing syntrophic relationships with fatty-acid fermenters, as well as homoacetogens able to carry out forward and reverse acetogenesis.
Methods: The Eye to Eye mentorship program assessed involved mentors and mentees who completed 12 in-person art sessions out of the normal 20 in-person sessions. The first main assessment was the BLD (Breger Learning Difference) Feedback Survey addressing one’s experience in the Eye to Eye program and which were completed at the end of the mentorship program and filled out by mentors, mentees, and mentees parents (one parent for each mentee). A total of 12 mentors, 6 mentees, and 6 mentee parents were included in the feedback survey final analysis. The second main assessments were the pre and post Behavior Assessment System for Child, Third Edition (BASC-3) provided to mentors, mentees, and mentees parents (one parent for each mentee). A total of 10 mentors, 5 mentees, and 5 mentee parents were included in pre and post BASC-3 final analysis. Fall 2019 (pre) and Spring 2020 (post) optional interviews involved 5 mentors and 3 mentees who showed interest and were comfortable participating with additional release forms.
Results: The program was generally positively rated in the feedback survey by mentors, mentees, and mentee parents. The highest responses for mentors, mentees, and mentee parents all incorporated average ratings of 4.0 or higher (out of 5.0) for perceived understanding of socio-emotional skills after Eye to Eye, experience in Eye to Eye, how having a mentor or mentee made them feel, and perceived change in self-awareness. All three groups reported fairly high ratings of improved self-awareness of 4.0/5.0 or above. No negative ratings were provided by any participants and the lowest response was no change. The BASC-3 evaluation found statistically significant improvement in mentors’ anxiety and atypicality and mentees’ sense of inadequacy.
Discussion: The Eye to Eye program was popular and well-rated despite only involving 12 in- person one-hour art sessions. The mentors, mentees, and mentee parents felt positive about the Eye to Eye program when answering the feedback survey. Some suggestions are made on how to improve this program to better enhance someone with learning differences future ability to succeed. Future research is needed to assess the true impact due to the COVID-19 epidemic and other limitations.