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This study employed machine learning to generate hypotheses about the factors (and their combinations) that induce activities in green spaces in neighborhoods from the perspective of behavioral change. A cross-sectional study was conducted in March 2021 using an online survey in Osaka, Japan (n = 5108). We conducted (1) probabilistic latent semantic analysis (pLSA) to extract latent classes related to activities in green spaces and (2) classification tree analysis with the latent classes as the objective variables. As a result of clustering through pLSA, six latent classes were extracted for activities in green spaces. These classes indicated a gradation of behavioral change stages as follows: (1) difficult access, (2) precontemplation, (3) contemplation, (4) preparation, (5) action–maintenance, and (6) stability. Classification tree analysis indicated that different factors at different behavioral change stages promoted or inhibited activities in green spaces. "Difficult access" was more likely applicable when urban residents lived in neighborhoods where both the built environment and the social environment were undesirable. "Precontemplation" was more likely applicable where urban residents did not have positive perceptions of the effects of green space and social interactions with neighbors. "Contemplation" and "preparation" did not show any growth in the classification tree. "Action–maintenance" was more likely applicable when urban residents engaged in social activities in the neighborhoods. "Stability" was more likely applicable when urban residents had positive perceptions of the effects of green space and social interactions with neighbors. [ABSTRACT FROM AUTHOR]

Mammals contain O-linked mannose residues with 2-mono- and 2,6-di-substitutions by GlcNAc in brain glycoproteins. It has been demonstrated that the transfer of GlcNAc to the 2-OH position of the mannose residue is catalyzed by the enzyme, protein O-mannose βl,2-Nacetylglucosaminyltransferase (POMGnT1), but the enzymatic basis of the transfer to the 6-OH position is unknown. We recently reported on a brain-specific β1,6N-acetylglucosaminyltransferase, GnT-IX, that catalyzes the transfer of GlcNAc to the 6-OH position of the mannose residue of GlcNAcβl,2-Manα on both the α1,3 and α1,6-linked mannose arms in the core structure of N-glycan (Inamori, K., Endo, T., Ide, Y., Fujii, S., Gu, J., Honke, K., and Taniguchi, N. (2003) J. Biol. Chem. 278, 43102-43109). Here we examined the issue of whether GnT-IX is able to act on the same sequence of the GlcNAcβ1,2-Manα in O-mannosyl glycan. Using three synthetic Set-linked mannose-containing saccharides, Manα1-Ser, GlcNAcβ1,2-Manαl-Ser, and Galβ1,4-GlcNAcβ1,2-Manα1-Ser as acceptor substrates, the findings show that [sup 14]C-labeled GlcNAc was incorporated only into GlcNAcβ1,2-Manα1-Ser after separation by thin layer chromatography. To simplify the assay, high performance liquid chromatography was employed, using a fluorescence-labeled acceptor substrate GlcNAcβ1,2-Manα1-Ser-pyridylaminoethylsuccinamyl (PAES). Consistent with the above data, GnT-IX generated a new product which was identified as GlcNAcβ1,2-(GlcNAcβ1,6-)Manα1-Ser-PAES by mass spectrometry and ¹H NMR. Furthermore, incorporation of an additional GlcNAc residue into a synthetic mannosyl peptide Ac-Ala-Ala-Pro-Thr(Man)-Pro-Val-Ala-Ala-Pro-NH[sub 2] by GnT-IX was only observed in the presence of POMGnTI. Collectively, these results strongly suggest that GnT-IX may be a novel β1,6-N-acetylglucosaminyltransferase that is responsible for the formation of the 2,6-branched structure in the brain O-mannosyl glycan. [ABSTRACT FROM AUTHOR]