Do political parties always prefer loyalists? Evidence from South Korea.

This paper examines the relationship between ideological polarization and party disloyalty, focusing on the moderating role of the status of a political party in the legislature, i.e., the ruling party or the opposition party. It hypothesizes that the ruling party is willing to endorse disloyal candidates whose issue positions are not close to their own party's platform, whereas the opposition party is likely to punish disloyal candidates to demonstrate party unity in the nomination process. The present study tests this hypothesis, using data from South Korea, where the nomination process for the parliamentary election is dominated by party leaders. The results are by and large consistent with the hypotheses. In line with previous studies, our results suggest that party loyalty is one of the driving forces of polarization in politics. In order to fully understand party polarization at the level of political elites, it is necessary to consider heterogeneous effects of party members' behavior on candidate selection, varying across the party's status, either the ruling party or the opposition party.

Effects of Daehwang-Hwanglyoun-Sasim-Tang on brain injury and cognitive function in mice caused by bilateral common carotid artery stenosis.

Among geriatric diseases, cerebrovascular disease ranks fourth according to the Causes of Death Statistics in 2019, Korea, and is the most common cause of acquired disorders in adults. Daehwang-Hwanglyoun-Sasim-Tang (DHST), a herbal prescription consisting of two herbal medicines, Rhei Rhizoma and Coptidis Rhizoma, has been reported to have anti-inflammatory, antioxidant, and anticancer effects. This study was conducted to confirm the anti-inflammatory mechanism of DHST treatment in ischemic brain injury and to confirm the role of DHST in cognitive function improvement. C57BL/6 male mice were randomly divided into four groups (sham operation, bilateral common carotid artery stenosis (BCAS) control, experimental group administered 5 mL/kg DHST, experimental group administered 50 mL/kg DHST), with each group containing five mice. After 1 week, DHST was orally administered for 4 weeks, 5 days a week, and then behavioral evaluation of learning and memory was performed. In addition, morphological changes in the neurons in the CA1 region of the hippocampus were observed. Inflammation-related factors were evaluated using western blot analysis. In the 50 mL/kg DHST (H-DHST) group, the expression of apoptosis-related proteins was reduced and neuronal damage was suppressed in the hippocampal CA1 region. However, cognitive improvement was observed in the H-DHST group that was attributable to anti-inflammatory and antiapoptotic pathways. In the 5 mL/kg DHST group, no significant effect was observed compared with the control group.