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AbstractPhytophthoraspecies, classified under Oomycota, cause significant damage to various crops and trees. The present study introduced Phytophthoraspecies, P. nagaiiand P. tentaculata, new to Korea, which pose notable risks to their respective host plants. Our research provided a comprehensive description of these species taking into account their cultural features, morphological characteristics, and molecular phylogenetic analysis using the internal transcribed spacer rDNA region and cytochrome c oxidase subunit mtDNA genes (cox1 and cox2) sequences. In addition, this study first evaluated the sensitivity of P. nagaiiand P. tentaculatato five anti-oomycete fungicides, finding both species most responsive to picarbutrazox and P. tentaculataresistant to fluazinam. The data can guide targeted treatment strategies and offer insights into effective control methods. The findings expand our understanding of the diversity, distribution, and management of Phytophthoraspecies in Korea.

Lipid vesicles are widely used for drug and gene delivery, but their structural instability reduces in vivo efficacy and requires specialized handling. To address these limitations, strategies like lipid cross‐linking and polymer–lipid conjugation are suggested to enhance stability and biological efficacy. However, the in vivo metabolism of these altered lipids remains unclear, necessitating further studies. A new stabilization technique without chemical modification is urgently needed. Here, a bio‐mimetic approach for fabricating robust multilamellar lipid vesicles to enhance in vivo delivery and stabilization of protein antigens is presented. This method leverages 1‐O‐acylceramide, a natural skin lipid, to facilitate the self‐assembly of lipid nanovesicles. Incorporating 1‐O‐acylceramide, anchoring lipid bilayers akin to its role in the stratum corneum, provides excellent stability under environmental stresses, including freeze–thaw cycles. Encapsulating ovalbumin as a model antigen and the adjuvant monophosphoryl lipid A demonstrates the vesicle's potential as a nanovaccine platform. In vitro studies show enhanced immune responses with both unilamellar and multilamellar vesicles, but in vivo analyses highlight the superior efficiency of multilamellar vesicles in inducing higher antibody and cytokine levels. This work suggests ceramide‐induced multilamellar lipid vesicles as an effective nanovaccine platform for enhanced antigen delivery and stability. This study introduces a biomimetic approach using 1‐O‐acylceramide to fabricate stable multilamellar lipid vesicles for enhanced antigen delivery in vaccines. These vesicles withstand environmental stresses and induce stronger immune responses in vitro and in vivo compared to traditional unilamellar vesicles, showing promise as an effective nanovaccine platform.

AbstractWhite mold (or Sclerotinia stem rot), caused by Sclerotiniaspecies, is a major air, soil, or seed-transmitted disease affecting numerous crops and wild plants. Microscopic or culture-based methods currently available for their detection and identification are time-consuming, laborious, and often erroneous. Therefore, we developed a multiplex quantitative PCR (qPCR) assay for the discrimination, detection, and quantification of DNA collected from each of the three economically relevant Sclerotiniaspecies, namely, S. sclerotiorum, S. minor, and S. nivalis. TaqMan primer/probe combinations specific for each Sclerotiniaspecies were designed based on the gene sequences encoding aspartyl protease. High specificity and sensitivity of each probe were confirmed for sclerotium and soil samples, as well as pure cultures, using simplex and multiplex qPCRs. This multiplex assay could be helpful in detecting and quantifying specific species of Sclerotinia, and therefore, may be valuable for disease diagnosis, forecasting, and management.

AbstractGlobal temperatures are steadily increasing, leading to significant changes in microbial diversity and ecology. In the present study, we isolated high-temperature-growing fungi and fungi-like group (Oomycota) strains from freshwater environments of Korea and identified them based on cultural, morphological, and multilocus phylogenetic analyses. As a result, we introduce Saksenaea(Fungi) isolates as a new species, Saksenaea longicollasp. nov. and record Phytophthora chlamydosporaand P. lagoariana(Oomycota) new to Korea. In the growth experiments, they exhibited high-temperature tolerance, which can grow at 35–40 °C but become inactive at 4 °C and below. This study confirms the presence of high-temperature-tolerant fungi and oomycetes in Korea and suggests that the Korean climate conditions are changing in favor of these species. This indicates that climate warming is altering microbial distributions in freshwater environments.

AbstractThe genus Pseudoperonospora, an obligate biotrophic group of Oomycota, causes the most destructive foliar downy mildew disease on many economically important crops and wild plants. A previously unreported disease by Pseudoperonosporawas found on oriental pickling melon (Cucumis melovar. conomon) in Korea, which is a minor crop cultivated in the temperate climate zone of East Asia, including China, Korea, and Japan. Based on molecular phylogenetic and morphological analyses, the causal agent was identified as Pseudoperonospora cubensis, and its pathogenicity has been proven. Importantly, two phylogenetic clades of P. cubensis, harboring probably two distinct species, were detected within the same plots, suggesting simultaneous coexistence of the two clades. This is the first report of P. cubensiscausing downy mildew on oriental pickling melon in Korea, and the confirmation of presence of two phylogenetic clades of this pathogen in Korea. Given the high incidence of P. cubensisand high susceptibility of oriental pickling melon to this disease, phytosanitary measures, including rapid diagnosis and effective control management, are urgently required.

In a multicenter study, 12 radiologists assisted by deep convolutional neural network software detected malignant pulmonary nodules on chest radiographs with a higher sensitivity and fewer false-positive findings per image compared with radiologists alone, irrespective of radiologist experience, nodule characteristics, or the vendor of the radiography acquisition system.

Biopanning refers to the processes of screening peptides with a high affinity to a target material. Microfluidic biopanning has advantages compared to conventional biopanning which requires large amounts of the target material and involves inefficient multiple pipetting steps to remove nonspecific or low-affinity peptides. Here, we fabricate a microfluidic biopanning system to identify a new gold-binding peptide (GBP). A polydimethylsiloxane microfluidic device is fabricated and bonded to a glass slide with a gold pattern that is deposited by electron-beam evaporation. The microfluidic biopanning system can provide high adjustability in the washing step during the biopanning process because the liquid flow rate and the resulting shear stress can be precisely controlled. The surface plasmon resonance analysis shows that the binding affinity of the identified GBP is comparable to previously reported GBPs. Moreover, molecular dynamics simulations are performed to understand its binding affinity against the gold surface in detail. Theoretical calculations suggest that the association and dissociation rates of the GBPs depend on their sequence-dependent conformations and interactions with the gold surface. These findings provide insight into designing efficient biopanning tools and peptides with a high affinity for various target materials.

We demonstrate that the extinction coefficient and the refractive index, as well as the layer thickness, are obtained by comparing the simulation of the transfer matrix method with the reflectance spectrum of a 3-μm-thick InGaAsP layer on an InP substrate. The results clarify the complicated behavior of the optical constant near the energy gap. While the refractive index in the transparent region around the energy gap where active devices operate is approximated by a linear temperature dependence, complex behavior results from the singularity of the gap. We also find that the energy gap shrinkage with temperature follows the empirical law of Varshni.

Despite the well-known advantages of lipid vesicles for drug and gene delivery, structural instability limits their practical applications and requires strictly regulated conditions for transport and storage. Chemical crosslinking and in situpolymerization have been suggested to increase the membrane rigidity and dispersion stability of lipid vesicles. However, such chemically modified lipids sacrifice the dynamic nature of lipid vesicles and obfuscate their in vivometabolic fates. Here, we present highly robust multilamellar lipid vesicles through the self-assembly of preformed, cationic large unilamellar vesicles (LUVs) with hydrolyzed collagen peptides (HCPs). The cationic LUVs undergo vesicle-to-vesicle attachment and structural reorganization through polyionic complexation with HCPs, resulting in the formation of multilamellar collagen-lipid vesicles (MCLVs). The resulting MCLVs exhibit excellent structural stability against variations in pH and ionic strength and the addition of surfactants. Particularly, the MCLVs maintain their structural stability against repeated freeze–thaw stresses, proving the unprecedented stabilization effect of biological macromolecules on lipid lamellar structures. This work provides a practically attractive technique for the simple and quick fabrication of structurally robust lipid nanovesicles without covalent crosslinkers, organic solvents, and specialized instruments.

A robust H\infty sliding mode descriptor observer for simultaneous state and disturbance estimation of uncertain system is developed. Inspired by a singular system theory, a descriptor observer design is presented to estimate some class of output disturbances. A sliding mode scheme is used for the observer to reconstruct the input fault based on the transformed coordinate system. Simulation study illustrates the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

We investigated the photoluminescence (PL) spectra of solution-based synthesized ZnO nanocrystalline (NC) films under various ambient conditions. While the PL spectra typically showed a sharp peak near 375 nm (near-band-edge, NBE) and a broad structure near 550 nm (deep level, DL), the NBE peak was enhanced and the DL emission was significantly suppressed in an O2-free atmosphere at room temperature. Interestingly, the PL spectra changed in an opposite manner in an O2-rich atmosphere. These findings indicate that the light emission from ZnO NC films is easily controlled by the O2concentration in the atmosphere at room temperature, which is clearly distinguished from the post-annealing effect.

Various lipid‐based nanocarriers have been developed for the co‐delivery of protein antigens with immunological adjuvants. However, their in vivo potency in vaccine delivery is limited by structural instability, which causes off‐target delivery and low cross‐presentation efficacies. Recent works employ covalent cross‐linking to stabilize the lipid nanostructures, though the immunogenicity and side effects of chemically modified protein antigens and lipids can cause a long‐lasting safety issue. Here robust “conjugation‐free” multilamellar protein antigen‐lipid hybrid nanovesicles (MPLVs) are introduced through the antigen‐mediated self‐assembly of unilamellar lipid vesicles for the co‐delivery of protein antigens and immunologic adjuvants. The nanocarriers coated with monophosphoryl lipid A and hyaluronic acids elicit highly increase antigen‐specific immune responses in vitro and in vivo. The MPLVs increase the generation of immunological surface markers and cytokines in mouse‐derived bone‐marrow dendritic cells compared to soluble antigens with adjuvants. Besides, the vaccination of mice with the MPLVs significantly increase the production of anti‐antigen antibody and interferon‐gamma via the activation of CD4+and CD8+T cells, respectively. These findings suggest that MPLVs can serve as a promising nanovaccine delivery platform for efficient antigen cross‐presentation through the efficient co‐delivery of protein antigens with adjuvants. Conjugation‐free multilamellar protein antigen‐lipid hybrid nanovesicles are prepared by protein‐mediated self‐assembly of large unilamellar lipid vesicles, following by surface coatings with immunological adjuvants and anti‐fouling polymers. The multilamellar vaccine formulation induces improved immune responses in vitro and in vivo. The antigen/adjuvant co‐delivery elicits the enhanced cross‐presentation of antigens in dendritic cells to activate CD4+and CD8+T cells simultaneously.

In the recent development of internal combustion engine, considerable increase in speed and power has been accomplished. This achievement, however, brought up various problems due to the excessive temperature of engine parts, which becomes a crucial factor in engine durability. In the present paper, temperature measurement of a marine engine was investigated experimentally. The adapter is made to pull out a thermocouple through the safety valve hole of the engine. The thermocouple is welded on the surface of the cylinder cover to measure the average temperatures of the engine cylinder cover. Ceramic adhesive was used for preventing the affect of high temperature combustion gas. The cylinder cover temperatures of the engine were measured by means of surface welding method. As a result, average temperatures of the engine cylinder cover were successfully in the range of 85~335oC. In the present study, the surface welding method was confirmed from the temperature measurement of cylinder cover in an experimental engine, and can be applied to large-sized marine engine without damage.

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We fabricated a solution-processed semitransparent organic solar cell from a transparent conductive polymer electrode. The top metal electrode was replaced with a transparent conductive polymer, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). The advantage of using the PEDOT:PSS conductive polymer is that organic solar cell (OPV) can be fabricated from solution process at plastic-compatible low temperature (<200°C). In addition, due to the absence of an opaque top metal electrode, the final OPVs exhibit semitransparency. The transmittance (T) of the final OPV was adjusted by changing the concentration of the organic materials in a solvent. As the concentration of the organic materials increased from 1.5 to 3.1%, the average weighted solar transmittance decreased from 53.9 to 45.2%. I-V characteristics of the OPVs with various transmittances were measured under the AM1.5G 100mW/m2solar simulator, and the conversion efficiency was 1.2, 2.0, 1.3% for the OPV with T of 53.9, 51.2, 45.2%, respectively.