Publications by authors named "Myung-Hwa Jung"

Article Synopsis
  • * The infectious pancreatic necrosis virus (IPNV) was isolated from some fish, but also, bacteria causing typical bacterial kidney disease (BKD) were identified using DNA sequencing and specific culture methods.
  • * Histopathological studies showed severe kidney damage, indicating that the mass mortality was linked to the bacterial infection rather than IPNV, marking the first BKD outbreak associated with this bacteria in farmed chum salmon in South Korea.
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Two-dimensional Ruddlesden-Popper series are an excellent system for tuning physical properties of the perovskite by controlling the layer number (). For instance, bandgap and exciton binding energies of the series gradually increase upon reducing via enhanced quantum and dielectric confinements. Here, we present findings that challenge the anticipated trend in electron-hole exchange interaction within (BA)MAPbBr ( = 1-3), which causes spin-dependent exciton level splitting into bright and dark states, where the latter is partially visible near the surface of the Br-based two-dimensional Ruddlesden-Popper series.

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Rock bream (Oplegnathus fasciatus) is one of the highly priced cultured marine fish in Korea. Rock bream iridovirus (RBIV) outbreaks in aquaculture farms may involve environmental factors, co-infection with other pathogenic microorganisms and grounded (raw) fish feed. This study evaluated the effects of RBIV-containing tissue intake on mortality and oral transmission in rock bream.

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Rock bream iridovirus (RBIV), belonging to Megalocytivirus, causes severe mortality in rock bream. Almost all deaths associated with RBIV are accompanied by splenic enlargement and anemia. Although red blood cells (RBCs) are involved in the immune response against viral infections, their involvement in rock bream has not yet been studied in terms of the immune response against RBIV.

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Rock bream iridovirus (RBIV) causes severe mass mortalities in rock bream (Oplegnathus fasciatus) and remains an unsolved problem in Korea aquaculture industry. In this study, we assessed the potential of ankyrin repeat (ANK)-containing proteins to induce protective immunity in RBIV-infected rock bream. Rock bream administered with ankyrin repeat-containing protein-based DNA vaccine (200 ng/fish) exhibited significant protection against at 4 and 8 weeks post vaccination to infected with 6.

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Production losses of olive flounder (Paralichthys olivaceus) have increased owing to viral haemorrhagic septicaemia virus (VHSV) infection. In this study, we determined safe concentrations of orally administered saponin and chitosan by analysing serum enzyme (AST/ALT) levels as biochemical markers of hepatic injury. Furthermore, we demonstrated the efficacy, duration of protection, and safety of saponin and chitosan-based vaccines with inactivated VHSV (IV).

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Rock bream iridovirus (RBIV) causes severe mortality in rock bream (Oplegnathus fasciatus) for last two decades. In view of this constant threat of RBIV to the rock bream industry, we conducted the present study with the aim to develop a safe and efficient remedial measure against the virus. In this study, we evaluated the safety and potentiality of squalene, aluminium hydroxide and saponin adjuvants, singly or in combinations, which can be used for developing an efficient inactivated (IV) vaccine to protect rock bream from RBIV infection.

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Article Synopsis
  • - Two-dimensional semiconductors, particularly 2D halide perovskite crystals, serve as an ideal environment for exploring excitons and biexcitons, though traditional photoluminescence interpretations may inaccurately estimate biexciton binding energies.
  • - The study reveals that biexcitons form via the binding of two dark excitons, with a significant bright-dark energy separation affecting spectral observations, leading to an underestimation of actual binding energies.
  • - Doping with manganese (Mn) enhances biexciton stability and paramagnetism, resulting in a slight increase in binding energy and exciton capture coefficient, though the measured values are still lower than previously reported, suggesting the need for reevaluation of bie
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With the emergence of Dirac fermion physics in the field of condensed matter, magnetic quantum oscillations (MQOs) have been used to discern the topology of orbits in Dirac materials. However, many previous researchers have relied on the single-orbit Lifshitz-Kosevich (LK) formula, which overlooks the significant effect of degenerate orbits on MQOs. Since the single-orbit LK formula is valid for massless Dirac semimetals with small cyclotron masses, it is imperative to generalize the method applicable to a wide range of Dirac semimetals, whether massless or massive.

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Article Synopsis
  • Topologically protected chiral skyrmions are unique spin textures important for both basic research and future spintronic technology.
  • The study explores a new method for creating MnSi films on sapphire substrates using lower vacuum conditions instead of the high-vacuum techniques typically required.
  • The research demonstrates that these polycrystalline MnSi films can stably exhibit skyrmion phases across various temperatures and magnetic fields, offering insights for future studies on skyrmion materials.
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An antiferromagnetic topological insulator has been predicted to be preserved by breaking both time-reversal symmetry and primitive lattice translational symmetry. However, the topological surface state has often been observed to disappear in an antiferromagnetic phase because the doped magnetic impurity acts as an extrinsic defect. In this study, we report the experimental signature of topological surface states coexisting with antiferromagnetic order in Sm-doped BiTe.

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Article Synopsis
  • Spintronic devices benefit from reduced switching current density by lowering the damping constant and saturation magnetization while maintaining strong magnetic characteristics.
  • The study reports successful creation of tetragonal 0 Mn Ga thin films with reduced saturation magnetization through specific substrate conditions, demonstrating improved quality and properties with less lattice mismatch.
  • The findings reveal that fewer Mn II atoms and higher Mn ion populations contribute to lower saturation magnetization, highlighting the potential for enhanced spintronic applications.
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The exchange interaction governs static and dynamic magnetism. This fundamental interaction comes in two flavours-symmetric and antisymmetric. The symmetric interaction leads to ferro- and antiferromagnetism, and the antisymmetric interaction has attracted significant interest owing to its major role in promoting topologically non-trivial spin textures that promise fast, energy-efficient devices.

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Rock bream iridovirus (RBIV) causes severe mass mortality in Korean rock bream () populations. To date, immune defense mechanisms of rock bream against RBIV are unclear. While red blood cells (RBCs) are known to be involved in the immune response against viral infections, the participation of rock bream RBCs in the immune response against RBIV has not been studied yet.

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The introduction of ferromagnetic order in topological insulators in general breaks the time-reversal symmetry and a gap is opened in topological surface bands. Various studies have focused on gap-opened magnetic topological insulators, because such modified band structures provide a promising platform for observing exotic quantum physics. However, the role of antiferromagnetic order in topological insulators is still controversial.

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The complex dielectric function and band-edge critical point structures of Bi1.85Gd0.15Te3 are reported for temperatures from 28 to 300 K and energies from 0.

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Rock bream iridovirus (RBIV) causes severe mass mortalities in rock bream (Oplegnathus fasciatus) in Korea. In this study, we investigated the potential of viral membrane protein to induce antiviral status protecting rock bream against RBIV infection. We found that fish administered with ORF008L (myristoylated membrane protein, MMP) vaccine exhibited significantly higher levels of survival compared to ORF007L (major capsid protein, MCP).

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The inhibition efficacy of an extract from Ecklonia cava (E. cava) was studied to determine whether the extract and compounds exhibited inhibitory activity against VHSV in the fathead minnow (FHM) cell line and following oral administration to the olive flounder. Based on its low toxicity and effective concentration, the E.

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Poly (I:C) showed promise as an immunoprotective agents in rock bream against rock bream iridovirus (RBIV) infection. In this study, we evaluated the time-dependent virus replication pattern and antiviral immune responses in RBIV-infected rock bream with and without poly (I:C) administration. In the poly (I:C)+virus-injected group, virus copy numbers were more than 18.

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Article Synopsis
  • Rock bream iridovirus (RBIV) significantly impacts rock bream survival, with higher water temperatures worsening immune response and infection susceptibility.
  • A study assessed how long it takes for RBIV to replicate and be eliminated from rock bream at various temperatures, finding that exposure to the virus for 7 days at 23°C resulted in 28% mortality by day 35.
  • Results showed that virus levels peaked between 20-22 days post-infection and could be eradicated within 70 days at a cooler temperature of 17°C, indicating that keeping the fish in a lower temperature environment can effectively eliminate the virus without high mortality risks.
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Article Synopsis
  • The study investigates how rock bream fish respond to the Rock bream iridovirus (RBIV), which causes high mortality rates in these fish in Korea.
  • It reveals that fish with high mortality (100% in 15 days) show a temporary increase in immune gene expressions like TLR9 and MyD88 before levels drop with viral loads, while fish with low (28% expected) and no mortality (0%) maintain higher expressions of these genes over time.
  • These findings suggest that a stronger innate immune response, involving key genes like MyD88 and TRAF6, helps fish survive viral infection, emphasizing that effective immune responses are crucial for reducing mortality from RBIV.
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Rock bream iridovirus (RBIV) causes severe mass mortalities in rock bream in Korea. CpG ODN 1668 showed promise as immunoprotective agents against RBIV infection in rock bream. In this study, we assessed innate/adaptive-related gene expression patterns in RBIV-infected rock bream with and without CpG ODN 1668 administration to determine important immune defense related factors that may affect fish survival.

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In this study, we evaluated the potential of poly (I:C) to induce antiviral status for protecting rock bream from RBIV infection. Rock bream injected with poly (I:C) at 2 days before infection (1.1 × 10) at 20 °C had significantly higher protection with RPS 13.

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Rock bream iridovirus (RBIV) disease in rock bream (Oplegnathus fasciatus) remains an unsolved problem in Korea aquaculture farms. CpG ODNs are known as immunostimulant, can improve the innate immune system of fish providing resistance to diseases. In this study, we evaluated the potential of CpG ODNs to induce anti-viral status protecting rock bream from different RBIV infection conditions.

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