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Lipid rafts are small and dynamic membrane compartments that are enriched with cholesterols or sphingolipids. The coalescence of small lipid rafts into a large lipid raft forms a signaling platform at the immunological synapse that plays a crucial role in controlling T cell activation. Cholesterol is a major component for the formation and function of lipid rafts, but the relationship between the spatial configuration of cholesterols and the lipid raft mediated membrane segregation as well as TCR signaling remains poorly understood. Here we used cholesterol conjugated DNA origami nanostructures, cholesterol nano-patch (CNP) to construct lipid rafts on intact live T cells. CNPs are two-dimensional DNA scaffolds that allow controlling the spatial presentation of cholesterols in the plasma membrane. CNPs efficiently bind onto the T cell membrane and rapidly induce large, polarized membrane cap structures which colocalize with flotillin-1. These CNP mediated membrane segregations, which we define as synthetic lipid rafts, drive membrane segregation of key signaling molecules including TCR and CD45, thereby triggering downstream TCR signaling and subsequently functional T cell responses without antigenic challenges. Our work highlights the potential of CNP in uncovering the mechanisms that lipid rafts induced by cholesterols drive membrane protein reorganization and control T cell signaling, and offers valuable insights into the design of antigen-independent immunotherapies.

In this study, we extended co-indexing of transcriptomes and epitopes (CITE) to the spatial dimension and demonstrated high-plex protein and whole transcriptome co-mapping. We profiled 189 proteins and whole transcriptome in multiple mouse tissue types with spatial CITE sequencing and then further applied the method to measure 273 proteins and transcriptome in human tissues, revealing spatially distinct germinal center reactions in tonsil and early immune activation in skin at the Coronavirus Disease 2019 mRNA vaccine injection site.

PurposeBased on the humane entrepreneurship perspective, this study examines the mediating relationship of organizational trust (OT) between corporate entrepreneurship (CE) and turnover intention (TI). In addition, it tests the moderating role of top talent management (TTM) between corporate entrepreneurship and OT.Design/methodology/approachThis study uses a multi-level research method to provide a conceptually comprehensive understanding of how CE works in an organization by testing the relationship between organizational practices and employees' outcomes.FindingsThis study found the mediating role of OT between cooperate entrepreneurship and employee TI. The authors also found the moderating role of TTM between CE and OT.Originality/valueIn this study, it is meaningful that OT is set as a mediating variable to identify the relationship between CE and workers' attitudes (TI). Although previous studies have shown a positive correlation between CE and TI, there was a lack of specific research on the indirect process by which CE affects workers' attitudes. This study looked more closely at the impact of CE on workers' attitudes using a multiple quasi-analysis.

Artificial Coral Reefs (ACRs) have been introduced to help solve coastal erosion problems, but their feasibility has not been assessed with field data. This study conducted a feasibility analysis of ACRs on their erosion mitigation effects by performing a case study of Cheonjin-Bongpo beach, South Korea. A numerical-physical combined analysis was carried out using a SWAN model simulation and physical model test with a scale of 1/25 based on field observations of Cheonjin-Bongpo beach. Both Dean’s parameter and the surf-scaling parameter were applied to comparative analysis between the absence and presence conditions of the ACR. The results for this combined method indicate that ACR attenuates the wave height significantly (59~71%). Furthermore, ACR helps decrease the mass flux (~50%), undertow (~80%), and maximum wave set up (~61%). The decreases in Dean’s parameter (~66%) and the surf-scaling parameter suggest that the wave properties changed from the dissipative type to the reflective type even under high wave conditions. Consequently, an ACR can enhance shoreline stability.

Nam, J.; Hong, S.; Lee, Y., and Kim, I., 2021. Correlation analysis between color and grain size of sand using a colorimeter. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 201–205. Coconut Creek (Florida), ISSN 0749-0208. To determine the cause of coastline changes, it is necessary to monitor various parameters such as wave data, changes in water depth, seabed topography and quality, as well as sea currents. This study aims to derive a correlation between grain size and color of sand on a coast undergoing erosion in Namae 3-ri∼Sodol beach. Therefore, for a period of six years (2013 to 2018), the depths of the foam zone, the breaking band, and other factors were divided for each cross-base line (DL(±) 0.00 m, DL(-) 3.00 m, DL(-) 6.00 m, and DL(-) 9.00 m). Seabed samples were collected from four vertices, and the median particle size and color characteristics of sand were recorded. Results showed that the average D50 particle sizes for DL(±) 0.00 m, DL(-) 3.00 m, DL(-) 6.00 m, and DL(-) 9.00 m were 0.615 mm, 0.432 mm, 0.416 mm, and 0.410 mm, respectively. In addition, the color of the sand that was passed through the colorimeter is represented by L* (white-black), a* (green-red), and b* (yellow-blue); these colors were expressed as a number to present a unique value. DL(±) 0.00 m = L* 61.12082, a* 5.757663, b* 17.93326; DL(-) 3.00 m = L* 61.81803, a* 5.03382, b* 16.79151; DL(-) 6.00 m = L* 61.74719, a* 4.886109, b* 16.54382; and DL(-) 9.00 m = L* 61.70353, a* 4.815222, and b* 16.42189. Furthermore, the sand color values a* and b* were coordinated, distributed on the beach, and then a color range converted to the value of the radius of the polar coordinate (r) was presented and compared with the particle size. To compare the a* and b* values with the sand particle size, r is expressed as a first-order function. The R-square of the first-order function was 0.9411, which was found to be highly reliable, and the exponential function was found to have a reliability of 0.5573. This result shows that the a* and b* values can be inferred according to the particle size of the sand.

Purpose The purpose of this paper is to examine the relationship between high commitment human resource practices (HCHRPs), conceptualized at the workplace level and employees’ attitudes, including affective commitment (AC) and turnover intention (TI). The study also tests the moderating role of cooperative labor–management relations (CLMR) between HCHRPs and organizational trust (OT). Design/methodology/approach Based on social exchange theory and trust commitment theory, the authors build a research model that explains employee behavior and empirically prove the model by using samples of 407 employees from South Korea. This study uses hierarchical linear regression and cross-level hypotheses based on hierarchical linear modeling. Findings The results demonstrate the positive impact of HCHRPs on an AC and TI, through OT. However, no moderating effect of CLMR between human resource management (HRM) practices and OT is observed. Originality/value Few theory-based studies test the direct linkage between HRM practices and outcomes. This study is designed with a multi-level research method to provide a conceptually comprehensive and deeper understanding of how HRM practices work in an organization by testing the relationship between organizational practices and employees’ outcomes.

Shin, S.; Nam, J.; Son, S.; Kim, I.H., and Jung, T.-H., 2017. Field observation and numerical modelling of rip currents within a pocket beach. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 229–233. Coconut Creek (Florida), ISSN 0749-0208. Understanding the occurrence mechanism of rip currents are very important in terms of the sediment transport and the water safety issues. In order to investigate the rip current occurrence mechanism, field observations were carried out at Chunjin beach and a numerical model was employed to simulate rip currents by using the field observation data. The collected data set includes the beach topography, bottom bathymetries, shoreline, sand sample, and incident waves for each season. The field observation data showed the spatiotemporal variations of shoreline and sand bars. The results also showed that the rip currents were generated near t...

To design a High-Performance Building (HPB), a performance goal should be clearly set from very early design phases, and then a decision path of what performance measures have been chosen in the past stages and shall be chosen in a later stage should be visible. In particular, for small- and mid-sized HPBs that are constructed with a smaller budget, if applicable performance measures are subjective to change, supplementary design costs can increase due to intermittent performance evaluations. To help this situation, we are developing a design expert system for small- and mid-sized buildings that pursues a balance between economic value and energy performance. The economy rule base suggests the most economic building volumetry and form in view of the site context, while the energy rule base suggests a series of energy-sensitive design variables and their options. Based on these rule bases, the expert system presents multiple design decision paths. The design decision support model of the inference engine helps stakeholders choose a preferred design path out of multiple paths, compare the paths, trace back the paths, and effectively revoke past decisions. An actual small retail and office construction project was chosen as a test case to compare the utility and robustness of the pilot system against the conventional design practice. In case of a rather risky design change scenario, the decision-making using the pilot expert system outperforms the conventional practice in terms of selecting designs with a good balance between economic value and energy performance. In addition, it was easier for users of the pilot system to forecast risks upon critical design changes and, in turn, to identify reasonable alternatives.

Kim, I.H.; Kim, J.H.; Nam, J.M.; Chang, S.Y.; Cho, W.C.; Do, K.D.; Kim, Y.J.; Song, D.S., and Lee, H.S., 2020. Changes in sand budget for littoral cell after coastal improvement project. In: Malvarez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 242–246. Coconut Creek (Florida), ISSN 0749-0208.The Munam2 harbor was constructed in 1989 and the direction of Munam river mouth was changed from the Gyoam beach to the Backdo beach in order to prevent sediment deposit within the harbor inside. In order to reduce erosion damage at the Gyoam beach, the CIP started in March 2014, and three submerged breakwaters were constructed in September 2016, as well as the beach nourishment. Therefore, the characteristics of shoreline change and bathymetric change were analyzed due to wave transmission after the implementation of submerged breakwaters in littoral drift cell. The beach monitoring was performed twice annually from 2014 to 2018, that the surveying items were shoreline change, beach profile and bathymetric change, including two times wave field observation during the monitoring period. As a result, the wave transmission rate between the W-2 and W-3 shows that the function of submerged breakwater is working effectively only when a significant wave, height over 1.3 m, occurs. However, it was analyzed that there was no wave energy reduction effect as a submerged breakwater when the significant wave height is below 0.3 m. After the submerged breakwaters were constructed to solve the erosion problem, the stable coastal line was formed on the Gyoam beach.

Kim, I.H.; Kim, J.H.; Nam, J.M.; Lee, H.S., and Song, D.S., 2019. Monitoring of coastal geomorphological changes in Wolchun Beach after LNG base construction. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 366-370. Coconut Creek (Florida), ISSN 0749-0208.Constructions of industrial facilities nearby coastal region often break a natural equilibrium between sediment budget and littoral current condition. The Wolchun beach, which is facing East Sea of South Korea, had a longshore stretch of 1.9 km before the LNG storing base was constructed. In this study, we analyzed the change patterns of the Wolchun beach topography caused by the installation of artificial structures, as well as coastal geomorphological changes. The control points in the study area were divided into 8 sections, each spaced 50 m pitch apart, for the trend analysis of the beach profiles. Also, the sea zone with 1.35 km2 area was divided into 6 sections with 300 m × 750 m per section, for the monitoring of water depth variation. The surveying results show that the area of the northern side of the Wolchun beach near the LNG storage base was continuously increased due to the accumulation of sediment after the construction of LNG base. On the contrary, the continuous erosion occurred on the south side of Wolchun beach, and it was observed that the water depth near the surf zone is deepened. Also, the bathymetric change of the test area was occurred actively, and the significantly unstable change of water depth in the region of about -10 m ∼ -15 m was confirmed to be generated by the breakwater with the disrupting of operable wave condition. It is found that the natural equilibrium has been collapsed along the unexpectedly formed shielding zone after the construction of the LNG base and the breakwater on the outside of the base.

Kim, J.; Kim, I.; Nam, J.; Song D., and Lee, H., 2019. Changes in the behavioral characteristics of the Gangmun and Anmok beaches following the construction of artificial reefs. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 26-30. Coconut Creek (Florida), ISSN 0749-0208.On the East coast of South Korea, there is only a small significant difference between low and high tides, meaning that seasonal wave directions appear clearly in recorded data. During summer, southeasterly waves dominate, and northward longshore drift occurs. In addition, the southward transport of littoral sediment occurs under the northeasterly waves that are dominant during winter. However, recent changes in the coastal environment, due to the development of coastal flooding prevention facilities, harbor development projects, and unusual weather conditions, have shown a tendency to increase the erosion of coastal areas. In other words, there is a repeating cycle of positive feedback, in which structures introduced to prevent a certain kind of coastal erosion cause different kinds of coastal erosion. In this study, we used field survey data to analyze the behavioral characteristics of the Gangmun and Anmok beaches for a period of seven years. The results show that the Gangmun and the Anmok beaches are very vulnerable to the effects of artificial constructs. Coastal erosion on Gangmun beach occurred through northward sediment transportation, caused by a dike that was built to avoid the closure of the mouth of Gyungpo stream. After an artificial reef and the groin were constructed to solve this erosion problem, the coastline stabilized. In the case of the Anmok beach, an imbalance in the sand budget supplied from the Namdae stream was brought about by the expansion of the Gangneung harbor, leading to significant beach erosion. After artificial reefs were installed on both beaches to prevent erosion, the area of each beach was increased and each beach's status was stabilized, as a salient beach.

Manganese (Mn) plays an important role in the etiology of several neurobehavioral disorders, but there is a lack of data regarding its specific effects on neurotransduction, especially dopaminergic neurotransduction. We investigated the relationship between motor deficits and alterations in the expression of tyrosine hydroxylase (TH) and dopamine D2-like receptors (DR), including the three dopaminergic subtypes, D2, D3, and D4, in low- and high-dose Mn-treated mice. After administration of Mn (intraperitoneal injections of 20 or 40 mg/kg MnCl(2).4H(2)O once per day for 5 d), motor activity and expression of TH and DR were examined in the striatum of the mouse brain. Mn treatment resulted in significant decrease in coordination and/or impaired motor learning after 5 d of treatment and this effect remained until 10 d after the end of Mn treatment. The expression of dopamine D2-like receptor D2 (DRD2), but not TH, DRD3, or DRD4, in the striatum was dose-dependent, and statistically significant increases were seen at the mRNA and protein levels. These findings indicate that Mn-induced motor deficits may be modulated in part by the expression of DRD2 in the striatum. In addition, our results suggest that the disturbance of dopaminergic neurotransmission mediated by DRD2 may be involved in the pathogenesis of Mn neurotoxicity.

Aluminum (Al) has been identified as a potential contributing factor in the etiology of several neurodegenerative disorders, but data regarding specific effects on neurotransduction, especially on dopaminergic neurotransduction, are lacking. The objective of this study was to determine the extent of expressional alterations in dopamine receptors (DRs) in two dopaminergic subtypes, D1 and D2, in low and high dose Al-treated mice. After administration of Al (four intraperitoneal injections of 30 or 60 mg/kg AlCl3·6H2O at 2 h intervals), expression of the dopamine D1-like and D2-like receptors (DRD1, DRD2) was examined in the cortex and striatum of mouse brain at bregma levels of 1.10, -0.10 and -1.34 mm. In the cortex, Al treatment decreased densities of DRD1 and DRD2 in a dose-dependent manner at all three bregma levels, especially in the high-dose Al group. Similarly, DRD1 and DRD2 expression in the striatum also exhibited dose dependency and statistically significant decreases were seen in the high-dose group, except in the striatum at bregma level - 1.34. These findings suggest that DR in the caudal striatum is more resistant to the effects of Al exposure than DR in the cortex or rostral striatum. In addition, our results suggest that disturbance of dopaminergic neurotransmission mediated by DRD1 and/or DRD2 may be involved in the pathogenesis of Al neurotoxicity. Human & Experimental Toxicology (2007) 26, 741 — 746