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A hallmark pathological feature of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) is the depletion of RNA-binding protein TDP-43 from the nucleus of neurons in the brain and spinal cord1. A major function of TDP-43 is as a repressor of cryptic exon inclusion during RNA splicing2–4. Single nucleotide polymorphisms in UNC13A are among the strongest hits associated with FTD and ALS in human genome-wide association studies5,6, but how those variants increase risk for disease is unknown. Here we show that TDP-43 represses a cryptic exon-splicing event in UNC13A. Loss of TDP-43 from the nucleus in human brain, neuronal cell lines and motor neurons derived from induced pluripotent stem cells resulted in the inclusion of a cryptic exon in UNC13A mRNA and reduced UNC13A protein expression. The top variants associated with FTD or ALS risk in humans are located in the intron harbouring the cryptic exon, and we show that they increase UNC13A cryptic exon splicing in the face of TDP-43 dysfunction. Together, our data provide a direct functional link between one of the strongest genetic risk factors for FTD and ALS (UNC13A genetic variants), and loss of TDP-43 function.

The five-dimensional process-oriented model of identity development delineates the formation and evaluation cycles of identity and includes ruminative exploration. In South Korea, individualistic and collectivistic cultures coexist, and such culture may influence the identity development process of young adults. However, identity development in Korean young adults has not been studied abundantly. In particular, the five-dimensional model of identity has never been used to study a Korean sample. In the present study, we tested the applicability of the five-dimensional model of identity with South Korean young adults between ages 19 and 25 (N = 548; Mage = 22.72; SDage = 1.93; 44.2% men). Specifically, we examined the measurement model of the Dimensions of Identity Development Scale (DIDS) and nomological net of the identity dimensions. Further, we conducted a cluster analysis to derive identity statuses. Results indicated that the five-factor model of the DIDS could be applied in our sample. The identity dimensions were related to each other and with external variables in ways that were mostly consistent with previous studies. Exploration in breadth and exploration in depth’s relations with commitment making, identification with commitment, and psychosocial functioning, which have not been consistent in previous studies, were positive. Finally, we identified five identity status clusters that resembled statuses identified in previous studies, but further research would be needed to ensure comparability.

Groundwater affects the load carrying behavior of foundations as the effective stress changes with the location of groundwater level (GWL) where the non-linear variations in stiffness and strength and the GWL influence zones below the foundation are involved. In this study, the load-settlement curve and the axial load capacity of piled-raft foundation with changes in GWL was investigated based on the results obtained from the finite element (FE) analyses. The full depth range of GWL from the top soil surface to the depth of well-below pile base was considered in the FE analyses. Changes in the effective stress and state-dependent soil stiffness with GWL were quantitatively evaluated and considered. It was found that the axial load capacity changed most significantly for GWL depths from 0 to 1.0 times the raft width, indicating that the GWL influence depth for piled rafts is controlled by raft size. The GWL effect factors for the load capacity (Cw) and settlement (Sw) of piled rafts were proposed. It was found that the values of Sw were larger than for unpiled rafts. The maximum value of Sw for piled rafts was 1.55 for GWL at the top surface, which decreased logarithmically with increases in the depth of GWL. The correlation of Sw to GWL was proposed.

We investigated the distributional pattern of mesozooplankton and the related environmental characteristics across the frontal zone in the South Sea of Korea during spring and autumn 2016. The frontal zone (FZ) was formed by Korean Southern Coastal Waters and Tsushima Warm Current, and the physical structure of front was more distinct during autumn than spring. The peaks of mesozooplankton abundance were not coincident (p > 0.05) with peaks of integrated chlorophyll-a (chl-a) concentrations (spring: chl-a = 44.5 mg m−2 at FZ, mesozooplankton = 8,198 inds.m−3 at coastal zone (CZ); autumn: chl-a=141.2 mg m−2 at CZ, mesozooplankton = 5,412 inds.m−3 at FZ). Cluster analysis divided the mesozooplankton community into FZ, CZ and offshore zone (OZ) mainly by the dominant copepods (adult and immature) during both seasons that was associated with chl-a based on principal component analysis. All the zones were characterized by temporal difference in occurrence of copepods, which can be explained by the cyclopoid-to-calanoid (Cy:Ca) ratio. Cy:Ca ratio was dependent mainly on the co-occurrence of higher concentrations of chl-a and cyclopoids at each zone between spring and autumn. Paracalanus copepodites dominated at all stations across the FZ during both periods. Cy:Ca ratio at FZ in spring showed a distinctively higher value than that of CZ and OZ, whereas the pattern was the opposite in autumn. These results indicated that the temporal distribution of mesozooplankton across the frontal zone in the South Sea was mainly characterized by the zonal characteristics of FZ, unlike CZ and OZ, and was the result of temporal differences in chl-a concentrations and the associated increase of cyclopoid copepods (Oithona spp.).

We investigated the feeding habits of Calanus sinicus during its four developmental stages as copepodite 4 (CIV), copepodite 5 (CV), adult males and females in early June 2015 at 12 sampling stations along the southern coast of Korea to the northern East China Sea, to better understand the role of C. sinicus in controlling phytoplankton stocks. Ingestion rate, daily ration as body carbon, population ingestion rate, and grazing impact were estimated using the gut pigment method. The mean biomass of CVs was the greatest (13.5 mg C m–3) and that of adult males was the lowest (0.7 mg C m–3). The ingestion rate per C. sinicus individual tended to increase with developmental stage, with the highest rate in adult females (519 ng chl ind–1 d–1) and the lowest rate in CIVs (305 ng chl ind–1 d–1). A significant correlation was found between ingestion rate and temperature, but not salinity or chlorophyll-a concentration. The daily ration of C. sinicus as body carbon significantly decreased with increased body weight, with the highest value found in CIVs (66.4%) and the lowest value in adult males (30%). Despite the high ingestion rate of the adults, the mean grazing impact of C. sinicus on phytoplankton biomass, in terms of chlorophyll-a concentration, was the highest in CVs (2.6%), followed by CIVs and adult females, and was the lowest in adult males (0.1%). The higher grazing impact of copepodites than adults underscores the importance of evaluating copepodite stages in the feeding studies of marine food webs.

Mesozooplankton community structure and environmental factors were monitored monthly at a fixed station off Tongyeong, southeastern coast of Korea, from 2011 to 2014 to better understand the variability of the mesozooplankton community in relation to changes in the marine environment. Total mesozooplankton density varied from 747 to 8,945 inds. m-3 with peaks in summer. The surface water temperature (r = 0.338, p < 0.05) and chlorophyll-a (Chl-a) concentration (r = 0.505, p < 0.001) were parts of the factors that may have induced the mesozooplankton peaks in summer. Copepods accounted for 71% of total mesozooplankton. Total copepod density, particularly cyclopoid copepods, increased during the study period. Cumulative sum plots and anomalies of the cyclopoid copepod density revealed a change of the cyclopoid density from negative to positive in June 2013. A positive relationship between cyclopoid copepods and the Chl-a concentration (r = 0.327, p < 0.05) appeared to be one of the reasons for the increase in cyclopoids. Dominant mesozooplankton species such as Paracalanus parvus s.l., Oikopleura spp., Evadne tergestina, Cirripedia larvae, Corycaeus affinis, Calanus sinicus, and Oithona similis accounted for 60% of total mesozooplankton density. Based on cluster analysis of the mesozooplankton community by year, the seasonal distinction among groups was different in 2014 compared to other years. P. parvus s.l. and its copepodites contributed most in all groups in all four years. Our results suggest that the high Chl-a concentration since 2013 may have caused the changes in mesozooplankton community structure in the study area.

The objective of this study was to enhance the lipid productivity in microalga Tetraselmis sp. through the salinity variation during cultivation. When marine alga Tetraselmis sp. was cultivated in a wide range of salinities, 0 through 70 practical salinity unit (PSU), enriched with F/2 medium, relatively low salinities below 35 PSU resulted in higher growth rates and lipid productivities under both N-deficient and -sufficient conditions, as compared to high salinities above 45 PSU. Nitrogen limitation did not stimulate lipid production in this species. Although high salinity increased lipid content, overall lipid productivities were lowered than those under low salinity conditions due to the decreased biomass production. When the salinity shifted from 35 to 22 PSU during cultivation, total lipid content increased from 20 to 26 (w/w) % within four days, and no significant change of fatty acids composition was observed.

The coefficient of lateral stress at rest, $$\hbox {K}_{0}$$ , is an important soil parameter that characterizes the geostatic stress state of soils. In this study, an experimental testing program was established to investigate the values of $$\hbox {K}_{0}$$ for granular materials that are subject to freezing and thawing. Various material conditions, including different fines contents, relative densities and freezing-thawing cycles, were considered in the testing program. The values of $$\hbox {K}_{0}$$ for thawed condition were higher than for unfrozen condition with net volume decrease. The effect of freezing and thawing became more pronounced as fines content increased while the effect of relative density was small. From the multi-cycled freezing-thawing tests, it was observed that the increase in $$\hbox {K}_{0}$$ was most significant during the first freezing-thawing cycle. For frozen condition, the values of $$\hbox {K}_{0}$$ were very low up to a certain limit stress level. Beyond the limit stress level, the values of $$\hbox {K}_{0}$$ became higher and close to those of unfrozen condition. The increases in $$\hbox {K}_{0}$$ with net volume decrease after freezing and thawing process was explained with internal changes in microstructure and stress state of soils.