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Along with barley and wheat, oats (Avena sativa) are cultivated as winter crops in Korea, and the total area for oat cultivation is 103 ha in 2021. From late March to early April 2021, sharp eyespot symptoms on oat (cv. Choyang) leaf sheaths and straws were observed in two commercial fields located in Haenam (N34°38'35.04588/E126°38'31.00668) and Gangjin (N34°38'9.46788/E126°37'19.44984), Jeollanam-do, Korea. The incidence was 5% and 7%, respectively. Small brown spots were irregular circles that began to appear on the lower sheaths, and the spots gradually enlarged in the upper part of the sheaths. The center of each lesion turned whitish-brown with dark brown margins, resulting in a blight of the sheaths. Three plants displaying typical sharp eyespot lesions were collected from each of two individual regions, Haenam and Gangjin. To isolate the causal pathogen, two infected tissues (5  5 mm) from the collected plants were surface-sterilized by treating them with 70% ethanol for 1 min and 1% NaClO for 1 min immediately after being treated with 95% ethanol for 1 min. Subsequently, the samples were rinsed three times with distilled water, dried with sterile filter paper, transferred to 1.5% water agar supplemented with 100 ppm streptomycin, and then incubated in the dark at 25°C. Hyphae emerging from the randomly selected three independent tissues from each location were subcultured on potato dextrose agar (PDA, Sparks, MD 21152, USA), resulting in three independent isolates (HNO-1, HNO-2, HNO-3) from Haenam and three (KJO1-1, KJO1-2, KJO1-3) from Ganjin after single-hypha-tip purification. Colonies on the PDA were pigmented white at first and subsequently changed to light brown after 2 weeks. All collected isolates formed globose and irregular dark brown to black sclerotia on PDA after 2 weeks. Binuclear hyphae were white to dark brown in color, branched at right angles with a septum near the branch, and multinucleate cells, suggesting that these isolates belonged to Ceratobasidium cereale (Boerema et al., 1977; Burpee, 1980; Sharon et al.,2008). For molecular identification, the ITS (GenBank accession nos. MW691851-53 for HNO-1 to HNO-3; MW691857-59 for KJO1-1 to KJO1-3), LSU (OQ397530-35), rpb2 (OQ409878-83), tef1 (OQ409884-89), and atp6 (OQ409890-95) regions of six isolates were amplified using the primer pairs ITS4/5 (White et al., 1990), LROR/LR5 (Vilgalys and Hester, 1990), bRPB2-6F/bRPB2-7.1R (Matheny, 2005; Reeb et al., 2004), TEF1-F/TEF1-R (Litvintseva et al., 2006), and ATP61/ATP62 (Kretzer and Bruns, 1999), respectively. The sequences of ITS region showed 99.7% identity with C. cereale strain WK137-56 (KY379365) and 99.8% with Ceratobasidium sp. AG-D (KP171639). Using the MEGA X program (Kumar et al. 2018), a maximum likelihood phylogenetic analysis based on the concatenated ITS-LSU, rpb2, tef1 and atp6 sequences placed the six isolates within a clade comprising C. cereale (Gónzalez et al.,2016; Ji et al., 2017; Tomioka et al., 2021; Li et al., 2014). Two representative isolate, HNO-1 and KJO1-1, were deposited in the Korean Agriculture Culture Collection (Accession No. KACC 49887 and 410268, respectively). For pathogenicity, the six isolates were cultured on sterilized ray grains at 25°C in the dark for 3 weeks as the inoculum. Five oat (cv. Choyang) seeds were sown per pot containing 80 g of the infected ray grains mixed with 150 g of composite soil and 150 ml of water (Baroker Garden Soil, Seoul Bio Co., LTD). The control was treated with 80 g of the sterilized ray grains mixed with 150 g of composite soil and 150 ml of water. All inoculated and control pots were placed in a 20°C growth chamber with a 12-h photoperiod and 65% humidity. Typical sharp eyespot symptoms were observed on the oat sheath of seedlings three weeks post-inoculation. No symptoms were observed in the control seedlings. The infection assays were repeated thrice, with similar results. The pathogen was successfully re-isolated, and its identity was confirmed via morphological and molecular analyses. In Korea, few etiological studies have been conducted on oats because they are less economical than barley and wheat. Sharp eyespot disease caused by C. cereale has already been reported in barley and wheat (Kim et al., 1991); however, this is the first report of this disease in oats in Korea.

Seven genera new to science, i.e.: Helmutiopsis, Huriopsis, Johnsheardia, Klauskalbia, Kudratovia, Kurokawia and Poeltonia of the Physciaceae are proposed for the ‘Rinodina’ atrocinerea, the ‘Rinodina’ xanthophaea, the ‘Rinodina’ cinnamomea, the ‘Heterodermia’ obscurata, the ‘Rinodina’ straussii, the ‘Anaptychia’ isidiata and the ‘Physconia’ grisea groups consequently that all form strongly supported monophyletic branches in a phylogeny analysis based on a combined matrix of nrITS and mtSSU sequences. Phylogenetic positions of species belonging to the genera Kashiwadia s. l., Leucodermia, Mischoblastia,Oxnerella, Phaeorrhiza s. l., Polyblastidium and Rinodinella s. l. are discussed. Oxnerella afghanica which for the first time recorded as parasitic lichen species from both epiphytic and saxicolous crustose lichens is designated as type species for the genus Oxnerella. Sequences of the recently described Physcia orientostellaris as well as Huriopsis xanthophaea and additional sequences of Kashiwadia aff. orientalis and Mischoblastia aff. oxydata are submitted to the GenBank. The positions of Polyblastidium casaterrinum from Costa Rica, ‘Rinodina’ efflorescens from Białowieża, Poland, and ‘Mischoblastia’ confragosula from Cambodia in the Physciaceae are confirmed in a phylogeny analysis based on the nrITS sequences. The presence of ‘extraneous mycobiont DNA’ in lichen associations is exemplified with earlier incorrect identifications of Heterodermia, Kashiwadia, Kurokawia,Oxnerella and Poeltonia specimens. Fifty-six new combinations are presented: Helmutiopsis alba (for Rinodina alba Metzler ex Arn.), Helmutiopsis aspersa (for Lecanora aspersa Borrer), Helmutiopsis atrocinerea (for Parmelia atrocinerea Fr.), Huriopsis chrysidiata (for Rinodina chrysidiata Sheard), Huriopsis chrysomelaena (for Rinodina chrysomelaena Tuck.), Huriopsis lepida (for Lecanora lepida Nyl.), Huriopsis luteonigra (for Rinodina luteonigra Zahlbr.), Huriopsis plana (for Rinodina plana H. Magn.), Huriopsis thiomela (for Lecanora thiomela Nyl.), Huriopsis xanthomelana (for Rinodina xanthomelana Müll. Arg.), Huriopsis xanthophaea (for Lecanora xanthophaea Nyl.), Johnsheardia cinnamomea (for Rinodina mniaroea var. cinnamomea Th. Fr.), Johnsheardia herteliana (for Rinodina herteliana Kaschik), Johnsheardia jamesii (for Rinodina jamesii H. Mayrhofer), Johnsheardia reagens (for Rinodina reagens Matzer et H. Mayrhofer), Johnsheardia zwackhiana (for Lecanora zwackhiana Kremp.), Kashiwadia austrostellaris (for Physcia austrostellaris Elix), Kashiwadia jackii (for Physcia jackii Moberg), Kashiwadia littoralis for Physcia littoralis Elix), Kashiwadia nubila (for Physcia nubila Moberg), and Kashiwadia tropica (for Physcia tropica Elix), Klauskalbia crocea (for Heterodermia crocea R. C. Harris), Klauskalbia flabellata (for Parmelia flabellata Fée), Klauskalbia obscurata (for Physcia speciosa (Wulfen) Nyl. *obscurata Nyl.), Klauskalbia paradoxa (for Heterodermia paradoxa Schumm et Schäfer-Verwimp), Kudratovia bohlinii (for Rinodina bohlinii H. Magn.), Kudratovia candidogrisea (for Rinodina candidogrisea Hafellner, Muggia et Obermayer), Kudratovia luridata (for Buellia luridata Körb.), Kudratovia metaboliza (for Rinodina metaboliza Vain.), Kudratovia pycnocarpa (for Rinodina pycnocarpa H. Magn.), Kudratovia roscida (for Lecanora roscida Sommerf.), Kudratovia straussii (for Rinodina straussii J. Steiner), Kudratovia terrestris (for Rinodina terrestris Tomin), Kurokawia bryorum (for Anaptychia bryorum Poelt), Kurokawia isidiata (for Anaptychia isidiata Tomin), Kurokawia mereschkowskii (for Physcia mereschkowskii Tomin), Kurokawia palmulata (for Psoroma palmulatum Michx.), Kurokawia runcinata (for Lichen runcinatus With.), Kurokawia stippea (for Parmelia aquila var. stippea Ach.), Lecania safavidiorum (for Oxnerella safavidiorum S. Y. Kondr., Zarei-Darki, Lőkös et Hur), Leucodermia erinacea (for Lichen erinaceus Ach.), Mischoblastia confragosula (for Lecanora confragosula Nyl.), Mischoblastia destituta (for Lecidea destituta Nyl.), Mischoblastia moziana (for Lecanora moziana Nyl.), Mischoblastia moziana subsp. parasitica (comb. et stat. nova for Rinodina moziana var. parasitica Kaschik et H. Mayrhofer), Mischoblastia ramboldii (for Rinodina ramboldii Kaschik), Mischoblastia vezdae (for Rinodina vezdae H. Mayrhofer), Oxnerella afghanica (for Rinodina afghanica M. Steiner et Poelt), Oxnerella castanomelodes (for Rinodina castanomelodes H. Mayrhofer et Poelt), Physciella nigricans (for Lecanora nigricans Flörke), Poeltonia elegantula (for Physconia elegantula Essl.), Poeltonia grisea (for Lichen griseus Lam.), Poeltonia isidiomuscigena (for Physconia isidiomuscigena Essl.), Poeltonia perisidiosa (for Physcia perisidiosa Erichsen), Poeltonia venusta (for Parmelia venusta Ach.), and Polyblastidium albicans (for Parmelia albicans Pers.) are proposed.

In June 2020, brown spot symptoms were observed in a commercial potato field located in Yeocheon, Gyeonggi Province, Korea. The symptoms were similar to those associated with early blight. Brown lesions on leaves were circular and expanded rapidly under high humidity and warm temperatures ranging 12°C at night to 30°C during daytime. Over 60% of potato (Solanum tuberosum L. cv. Superior) leaves showed the symptoms. For fungal isolation, infected leaf tissues (5 × 5 mm) from 14 infected samples were immersed in 70% ethanol for 1 min, rinsed three times in sterilized water, dried, placed on water agar amended with 100 ppm of streptomycin, and then incubated in the dark at 25°C. Hyphae emerging from the tissues were subcultured on V8-Juice agar (8% of V8-Juice, 1.5% agar, pH 7), and the obtaining cultures were subjected to single-spore isolation, resulting in 14 isolates (SYP-934~947). Three representative isolates, SYP-934 to SYP-936, were deposited in the Korean Agriculture Culture Collection (Accession Nos. KACC 410058 to KACC 410060). Conidia (n = 100) produced on the colony were brown, ellipsoid to ovoid with walls ornamented, 1 to 6 transverse and 0-3 vertical septa, and length × width of 20-45 × 7 to 24 μm (n = 100). Their morphological characteristics were consistent with Alternaria alternata (Simmons, 2007; van der Waals et al., 2011; Woundenberg et al. 2015). Sequences of the following loci in the 14 isolates were determined as described in Woundenberg et al. (2013 and 2014: the internal transcribed spacer (primer pairs VG9/ITS4, GenBank accession nos. OP581413-25), glyceraldehyde-3-phosphate dehydrogenase (gpd1/gpd2, OP588286-99), RNA polymerase second largest subunit (RPB2-5F2/fRPB2-7cR, OP588314-27), translation elongation factor 1-alpha (EF1-728F/EF1-986R, OP588300-13), Alternaria major allergen gene (Alt-For/Alt-Rev, OP588328-41), endopolygalacturonase (PG3/PG2b, OP588342-55), and an unknown gene region (OPA10-2R/OPA10-2L, OP588356-68). A neighbor-joining phylogenetic analysis based on the concatenated gene sequences, which was performed using the MEGA X program (Kumar et al., 2018), placed the 14 isolates in the clade containing A. alternata isolates. To test pathogenicity, one-month-old potato (S. tuberosum cv. Superior) plants grown in a 25°C growth chamber were sprayed with conidial suspensions (1×106 conidia/mL) prepared from 14-day-old cultures of three isolates (KACC 410058 to KACC 410060). Sterile distilled water was used as the control treatment. The inoculated pots were placed in a plastic box to maintain high humidity and incubated in the dark at 25°C for 2 days. The plants were transferred to a growth chamber (16h light with over 70% humidity at 25°C). Symptoms were first observed after 3 days post inoculation (dpi) with all three isolates, and severe brown spot symptoms were observed after 7 dpi. No symptom was observed in the control treatment. The pathogenicity assay was repeated at triplicate. Reisolated cultures from lesions were confirmed to be A. alternata based on their sequence at the rpb2 locus, thus fulfilling Koch’s postulates. Alternaria alternata has been reported to cause brown spot and leaf blight on potato leaves in Israel (Dorby et al., 1984) and South Africa (van der Waals., et al. 2011). To our knowledge, this study is the first report of A. alternata causing brown spot disease in Korea.

Oat (Avena sativa) is one of the Korean winter crops, and oat consumption has been increasing because it is widely perceived as a superfood. Recently, various fungal diseases have been reported likely due to climate changes during the winter season in Korea (Choi et al., 2018; Kim, 2020). During the 2020-2021 winter to spring, we surveyed new fungal diseases among cereals, including oats, in the southern region of Korea. In April 2021, brown leaf spots on oat leaves were observed in Gangjin, Jeollanam-do, Korea. These brown spots were irregular circles, ranging from 2–7 mm in diameter. Samples from three infected leaves were surface sterilized by treating them with 70% ethanol for 1 min and 1% NaOCl for 1 min. The samples were subsequently rinsed at least twice with distilled water and dried with a sterile paper towel before being placed on 1.5% water agar supplemented with 100 ppm streptomycin. Hyphal tips derived from infected tissues after incubation at 25C for 7 days were transferred to a fresh potato dextrose agar (PDA). Three isolates, labeled as KJO-AN2-S1, KJO-AN2-S2 and KJO-AN2-S3, were obtained via single hyphal tip purification. Colonies on PDA were pigmented vermilion and subsequently turned to saffron color with irregular margins after 7 days. Conidia produced on PDA were golden to dark brown, globose to subglobose, solitary, and measured 15.5–21.5 μm in diameter (n=50). Cultural and morphological characteristics suggested that these isolates belong to Epicoccum species (Chen et al. 2017). For identification by sequencing, the ITS (MW691866-68), tub2 (MW691872-74), and rpb2 (MW691869-71) regions of three isolates were amplified using the primer pairs ITS5/ITS4 (White et al., 1990), Btub2Fd/ Btub4Rd (Woudengerg et al., 2009), and RPB2-5F2 (Sung et al., 2007)/fRPB2-7cR (Liu et al., 1999), respectively. A maximum likelihood phylogenetic analysis based on the concatenated ITS, tub2, and rpb2 sequences placed the three isolates within a clade comprising E. tobaicum CBS 384.36. A mycelial plug (5 mm diameter) was inoculated onto wounded and unwounded leaves of healthy 12-day-old oat (cv. Choyang) seedlings. The control leaves were inoculated with a sterile PDA plug. All inoculated and control plants were placed in a plastic box and incubated at 20℃ in darkness with 100% humidity. After 1 day, the inoculated mycelial plug or sterile PDA plug from plants was removed; the plants in plastic boxes were then transferred to a growth chamber set at 20℃ with 12 h light and 60–70% humidity. While brown spot lesions were observed in both unwounded and wounded leaves 7 days post-inoculation, both wounded and unwounded control leaves remained asymptomatic. The pathogen was recovered from all symptomatic leaf tissues but could not be isolated from control leaves. The re-isolated pathogen was identified as E. tobaicum through morphological characterization and sequence-based identification, fulfilling Koch’s postulates. This study is the first to report a causal relationship between E. tobaicum and brown leaf spot disease of oat in Korea. Identification of this newly emerging fungal disease on oats will help prepare for effectively managing this disease.

An endolichenic fungus Xylaria grammica EL000614 produces grammicin, a potent nematicidal pyrone derivative that can serve as a new control option for root-knot nematodes. We optimized an Agrobacterium tumefaciens-mediated transformation (ATMT) protocol for X. grammica to support genetic studies. Transformants were successfully generated after co-cultivation of homogenized young mycelia of X. grammica with A. tumefaciens strain AGL-1 carrying a binary vector that contains the bacterial hygromycin B phosphotransferase (hph) gene and the eGFP gene in T-DNA. The resulting transformants were mitotically stable, and PCR analysis showed the integratin of both genes in the genome of transformants. Expression of eGFP was confirmed via fluorescence microscopy. Southern analysis showed that 131 (78.9%) out of 166 transformants contained a single T-DNA insertion. Crucial factors for producing predominantly single T-DNA transformants include 48 h of co-cultivation, pre-treatment of A. tumefaciens cells with acetosyringone before co-cultivation, and using freshly prepared mycelia. The established ATMT protocol offers an efficient tool for random insertional mutagenesis and gene transfer in studying the biology and ecology of X. grammica.

An intraoperative air leak test (ALT) is commonly used to detect mechanical defects following a bowel anastomosis, although its efficacy is uncertain. This study aimed to evaluate the efficacy of ALT for preventing anastomotic leakage (AL) following rectal excision. We reviewed our database for patients with rectal cancers who had undergone curative surgery between January 2012 and January 2018. Patients were grouped according to whether or not an ALT was performed. Propensity score analyses were performed to compare outcomes for groups in a 1:1 case-matched cohort. In total, 1,191 patients underwent rectal excision; 438 (219 in each group) formed the case-matched cohort for analysis. The protective stoma rate was 16.0% and 14.6% in the ALT and the no-ALT groups, respectively (p = 0.791). In the ALT group, 2 patients (0.9%) showed a positive result and were treated with rectal tube drainage, resulting in no leakage. There was no significant between-group difference in postoperative AL rate (ALT group: 4.6%, no-ALT group: 4.1%, p = 1.000). ALT played a minimal role in preventing AL following rectal excision. Further studies are warranted to validate our results and clarify whether AL can be prevented with ALT or alternative methods.

The catalytic activity for dehydrogenation of C2H6 and successive CO2 activation was studied by using hierarchically-structured bimetallic FeM/ZSM-5 (M=Ce, Ga, and Sn metal) to verify the redox property of the Fe nanoparticles and metal promoters on the acidic ZSM-5. Based on the surface characteristics, the reducibility and oxygen vacant sites of metal oxides on the ZSM-5 largely altered the reduction-oxidation nature and catalytic cracking behavior. The metal-promoted Fe/ZSM-5, especially with CeO2 promoter on the FeCe/ZSM-5, revealed excellent redox cycles and higher steady-state dehydrogenation activity such as a comparable C2H6 conversion of 6.1% as well as C2H4 selectivity of 89.8% at 600 °C with a larger CO production with 9.7 mmol/g by CO2 activation at 700 °C. This observation was attributed to the incorporated partially reducible CeO2 species by enhancing their interaction with ZSM-5 as well as by easily stabilizing the oxidation states of Ce and Fe metal oxides with its higher thermal stability during C2H6 dehydrogenation through an initial oxidative dehydrogenation followed by a steady-state catalytic cracking and subsequent CO2 activation to CO.

Three genera new for science, i.e. Candelinella S. Y. Kondr. for the Candelariella makarevichiae group, Opeltiella S. Y. Kondr. for the Candelaria fraudans group, as well as Protocandelariella Poelt, D. Liu, J.-S. Hur et S. Y. Kondr. for the Candelariella subdeflexa group are proposed for robust monophyletic branches of the Candelariaceae on the basis of three-gene phylo- geny (i.e. concatenated nrITS, 12S mtSSU and 28S nrLSU sequences). Eight new combinations, i.e. Candelinella makarevichiae (for Candelariella makarevichiae S. Y. Kondr., L. Lokos et J.-S. Hur), Candelinella deppeanae (for Candelariella deppeanae M. Westb.), Opeltiella fraudans (for Candelaria fraudans Poelt et Oberw.), Opeltiella fibrosoides (for Candelaria fibrosoides M. Westb. et Froden), Opeltiella rubrisoli (for Candelariella rubrisoli D. Liu et J.-S. Hur), Opeltiella canadensis (for Candelariella canadensis H. Magn.), Protocandelariella subdeflexa (for Lecanora subdeflexa Nyl.), Protocandelariella blastidiata (for Candelariella blastidiata L. Yakovchenko) are provided.Molecular data provided for Candelinella makarevichiae (including holotype and iso- type), as well as additional specimens of Candelaria asiatica from South Korea for the first time. The latter species (Candelaria asiatica) from China, as well as’Candelaria’ murrayi from Argentina, South America are recorded for the first time. Voucher of Candelariella vitellina from Antarctica is also identified based on molecular phylogeny. It is for the first time shown that ’Candelaria’murrayi is positioned in the outermost position to Candelaria s. str. branch of the phylogenetic tree of the Candelariaceae, and may belong to another genus. Status of the ’Candelariella’medians group, the’Candelariella’ placodizans group, as well as single species ’Candelariella’reflexa and’Candelaria’ pacifica, forming separate branches outside the Candelariella s. str. and Candelaria s. str. clades, will be clarified when additional molecular data will be accumulated. Candelariella subsquamulosa D. Liu et Hur, recently described from South Korea (Liu et al. 2019), proved to be a new synonym of Candelinella makarevichiae.

Comonomers vinylimidazole, methyl acrylate, and acrylic acid were added to acrylonitrile to synthesize two polymers, poly(acrylonitrile-co-1-vinylimidazole) and poly(acrylonitrile-co-N-vinylimidazole-co-methyl acrylate-co-acrylic acid), with the goal of enhancing their melt processability for their use as carbon fibers. The two polymers were melt-extruded, but the as-spun filaments were brittle. Therefore, glycerol was mixed with the polymers to improve their spinnability and drawability. The addition of glycerol to the polyacrylonitrile copolymer and tetrapolymer reduced their melt viscosity, enhanced their melt spinnability, and improved their drawability. When 15 % (w/w) glycerol was added, the melt viscosity of the two polymers was reduced to below 1000 Pa·s at a shear rate of 100 s-1, and the tensile strength of the resulting filaments was high enough for them to be used as precursor filaments for carbon fibers. Furthermore, a draw ratio of over 5.5 was achieved for the melt spun filaments of mixtures of the copolymer and tetrapolymer with 15 % glycerol (w/w) at a temperature of 150 °C.

An endolichenic fungus, Xylaria grammica strain EL000614, showed strong nematicidal effects against plant pathogenic nematode, Meloidogyne incognita by producing grammicin. We report genome assembly of X. grammica EL000614 comprised of 25 scaffolds with a total length of 54.73 Mb, N50 of 4.60 Mb, and 99.8% of BUSCO completeness. GC contents of this genome were 44.02%. Gene families associated with biosynthesis of secondary metabolites or regulatory proteins were identified out of 13,730 gene models predicted.

While 2D transition metal dichalcogenides (TMDs) are promising building blocks for various optoelectronic applications, limitations remain for multilayered TMD-based photodetectors: an indirect bandgap and a short carrier lifetime by strongly bound excitons. Accordingly, multilayered TMDs with a direct bandgap and an enhanced carrier lifetime are required for the development of various optoelectronic devices. Here, periodically arrayed nanopore structures (PANS) are proposed for improving the efficiency of multilayered p-WSe

The probing of fundamental photophysics is a key prerequisite for the construction of diverse optoelectronic devices and circuits. To date, though, photocarrier dynamics in 2D materials remains unclear, plagued primarily by two issues: a large exciton binding energy, and the lack of a suitable system that enables the manipulation of excitons. Here, a WSe

Zero-dimensional-two-dimensional (0D-2D) hybrid optoelectronic devices have demonstrated high sensitivity and high performance due to the high absorption coefficient of 0D materials with a tunable detection range and a high carrier transport property of 2D materials. However, the reported 0D-2D hybrid devices employ toxic nanomaterials as sensitizing layers, which can limit the practical applications. In this study, we first fabricated the 0D-2D hybrid photodetector using nontoxic InP quantum dots (QDs) as a light-absorbing layer and black phosphorus (BP) as a transport layer. The surface treatment using 1,2-ethanedithiol and thermal treatment were carried out to remove the surface long ligands of colloidal QDs, which can accelerate the charge injection of the photogenerated carriers through the interfaces between InP QDs and BP. The InP QDs/BP hybrid photodetector demonstrates a high responsivity of 1 × 109 A/W and detectivity of 4.5 × 1016 Jones at 0.05 μW cm-2 under 405 nm illumination. The results show that 0D-2D hybrid photodetectors based on III-V semiconducting QD materials can be optimized for high-performance photodetectors.

Several buellioid specimens were collected from South Korea during field surveys and two new species are described based on morphology, chemistry, and molecular phylogeny. Buellia boseongensis sp. nov. is similar to B. polyspora but differs in having a UV + orange thallus and cryptolecanorine apothecia. Sculptolumina coreana sp. nov., resembles S. japonica, but differs in having a smooth entire continuous thallus, which reacts K–, a narrower excipulum, thicker epihymenium, narrower subhymenium, and in containing secondary metabolites other than flavo-obscurin and myeloconone. A key to the buellioid lichens reported from Korea is also presented.

Lichens are prolific producers of natural products of polyketide origin. We previously described a culture of lichen-forming fungus (LFF) Cladonia macilenta that produces biruloquinone, a purple pigment that is a phenanthraquinone rarely found in nature. However, there was no genetic information on the biosynthesis of biruloquinone. To identify a biosynthetic gene cluster for biruloquinone, we mined polyketide synthase (PKS) genes from the genome sequence of a LFF isolated from thalli of C. macilenta. The 38 PKS in C. macilenta are highly diverse, many of which form phylogenetic clades with PKS previously characterized in non-lichenized fungi. We compared transcriptional profiles of the 38 PKS genes in two chemotypic variants, one producing biruloquinone and the other producing no appreciable metabolite in vitro. We identified a PKS gene (hereafter PKS21) that was highly upregulated in the LFF that produces biruloquinone. The boundaries of a putative biruloquinone gene cluster were demarcated by co-expression patterns of six clustered genes, including the PKS21. Biruloquinone gene clusters exhibited a high degree of synteny between related species. In this study we identified a novel PKS family responsible for the biosynthesis of biruloquinone through whole-transcriptome analysis.

Pears (Pyrus pylifolia L.) are cultivated nationwide as one of the most economically important fruit trees in Korea. At the end of October 2019, bleeding canker was observed in a pear orchard located in Naju, Jeonnam Province (34°53'50.54″ N, 126°39'00.32″ E). The canker was observed on trunks and branches of two 25-year-old trees, and the diseased trunks and branches displayed partial die-back or complete death. When the bark was peeled off from the diseased trunks or branches, brown spots or red streaks were found in the trees. Bacterial ooze showed a rusty color and the lesion was sap-filled with a yeasty smell. Trunks displaying bleeding symptoms were collected from two trees. Infected bark tissues (3 × 3 mm) from the samples were immersed in 70% ethanol for 1 minute, rinsed three times in sterilized water, ground to fine powder using a mortar and pestle, and suspended in sterilized water. After streaking each suspension on Luria-Bertani (LB) agar, the plates were incubated at 25°C without light for 2 days. Small yellow-white bacterial colonies with irregular margins were predominantly obtained from all the samples. Three representative isolates (ECM-1, ECM-2 and ECM-3) were subjected to further characterization. These isolates were cultivated at 39 C, and utilized (-)-D-arabinose, (+) melibiose, (+)raffinose, mannitol and myo-inositol but not 5-keto-D-gluconate, -gentiobiose, or casein. These isolates were identified as Dickeya sp. based on the sequence of 16S rRNA (MT820458-820460) gene amplified using primers 27f and 1492r (Heuer et al. 2000). The 16S rRNA sequences matched with D. fangzhongdai strain ND14b (99.93%; CP009460.1) and D. fangzhongdai strain PA1(99.86%; CP020872.1). The recA, fusA, gapA, purA, rplB, and dnaX genes and the intergenic spacer (IGS) regions were also sequenced as described in Van der wolf et al. (2014). The recA (MT820437-820439), fusA (MT820440-820442), gapA (MT820443-820445), purA (MT820446-820448), rplB (MT820449-820451), dnaX (MT820452-820454) and IGS (MT820455-820457) sequences matched with D. fangzhongdai strains JS5, LN1 and QZH3 (KT992693-992695, KT992697-992699, KT992701-992703, KT992705-992707, KT992709-992711, KT992713-992715, and KT992717-992719, respectively). A neighbor-joining phylogenetic analysis based on the concatenated recA, fusA, gapA, purA, rplB, dnaX and IGS sequences placed the representative isolates within a clade comprising D. fangzhongdai. ECM-1 to 3 were grouped into a clade with one strain isolated from waterfall, D. fangzhongdai ND14b from Malaysia. Pathogenicity test was performed using isolate ECM-1. Three two-year-old branches and flower buds on 10-year-old pear tree (cv. Nittaka), grown at the National Institute of Horticultural and Herbal Science Pear Research Institute (Naju, Jeonnam Province in Korea), were inoculated with 10 μl and 2 μl of a bacterial suspension (108 cfu/ml), respectively, after wounding inoculation site with a sterile scalpel (for branch) or injecting with syringe (for flower bud). Control plants were inoculated with water. Inoculated branches and buds in a plastic bag were placed in a 30℃ incubator without light for 2 days (Chen et al. 2020). Both colorless and transparent bacterial ooze and typical bleeding canker were observed on both branches and buds at 3 and 2 weeks post inoculation, respectively. No symptoms were observed on control branches and buds. This pathogenicity assay was conducted three times. We reisolated three colonies from samples displaying the typical symptoms and checked the identity of one by sequencing the dnaX locus. Dickeya fangzhongdai has been reported to cause bleeding canker on pears in China (Tian et al. 2016; Chen et al. 2020). This study will contribute to facilitate identification and control strategies of this disease in Korea. This is the first report of D. fangzhongdai causing bleeding canker on pears in Korea.

The synergetic effects of Co oxides on the Ni/CoAl (NCA) catalysts were observed at an optimal molar ratio of Al/Co = 2 (NCA(2)) due to the partial formations of thermally stable spinel CoAl2O4 phases for the steam reforming of propane (SRP). The optimal content of the spinel CoAl2O4 phases on the NCA(2) was responsible for the formation of the relatively active oxophilic metallic Co nanoparticles with a smaller amount of less active NiAl2O4 on the surfaces by preserving the relative amount of metallic Co of 68% and 52% in the reduced and used catalysts, which enhanced the catalytic activity and stability with the largest specific rate of 1.37 C3H8/(Ni + Co)h&minus, 1 among the tested NCA catalysts. The larger or smaller amounts of Co metal on the less active NCA mainly caused the preferential formation of larger aggregated Ni nanoparticles ~16 nm in size due to their weaker interactions, or induced the smaller formations of active metal phases by selectively forming the spinel NiAl2O4 phases with ~60% in the NCA(4), resulting in a fast deactivation.

Osteoporosis is a metabolic disorder that increases the risk of fractures of bone. Receptor activator of nuclear factor-kappa B ligand (RANKL) signaling ultimately activates nuclear factor-activated T cells c1 (NFATc1), a major transcription factor for osteoclast formation. Lichens are symbiotic organisms composed of fungi and algae partners, which are known to be rich repositories of natural metabolites. There was few investigational study on the effect of lichen substances for osteoporosis treatment. This study conducted to elucidate anti-osteoporosis effects of Ramalina litoralis, one of the common saxicolous lichens distributed in the coastal area of Korean Peninsula. In this study, we examined the effects of Ramalina litoralis extract on the osteoclast in osteoporosis. We studied the inhibition of genes and proteins associated with the inhibition of osteoclast by extracts, and the resorptive pit assay for osteoclast function. The extract of Ramalina litoralis reduced the levels of mRNA expression of NFATc1, osteoclast-related receptor (OSCAR), cathepsin K and tartaric acid-resistant phosphatase (TRAP). It also inhibited the translational expression of NFATc1, a major protein in osteoporosis. The inhibitory effect of extracts of Ramalina litoralis on osteoclast differentiation was confirmed using resorptive pit analysis. The extract of Ramalina litoralis inhibited the expression level of NFATcl through the RANKL signaling pathway. This study demonstrates the anti-osteoclastic effect of Ramalina litoralis extract, which can be applied for the effective treatment of osteoporosis, and will serve as an important candidate for making therapeutic agents.

Four new compounds, phomalichenones A-D (1-4), and seven known compounds (5-11) were isolated from the cultures of an endolichenic fungus Phoma sp. EL002650. Their structures were determined by the analysis of their spectroscopic data (NMR and MS). Compounds 1 and 6 inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. In addition, compound 1 diminished the protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and decreased the mRNA expression levels of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin(IL)-1β, and IL-6.

Recently, black phosphorus (BP) with direct band gap exhibited excellent potential for optoelectronic applications because of its high charge carrier mobility and low dark current as well as the variable band gap of 0.3-1.5 eV depending on the number of layers. However, few-layer BP-based phototransistors (photo-FETs) have been limited in sensitivity and wavelength selectivity. To overcome the drawback of these photo-FETs, we studied hybrid photo-FETs combined with the novel properties of the two materials between the channel and sensitizer layers. By combining a strong absorbance of a quantum dot (QD) layer and a two-dimensional layer material with high carrier mobility, the hybrid photo-FETs are expected to produce high-performance photodetectors that can effectively control the responsivity, detectivity, and response time. In this study, we demonstrate that the photogenerated carriers formed from QD sensitizer layers migrate to the BP transport layer with high charge mobility and not only improve the photodetector performance but also enhance the photodoping effect of the BP transport layer with an ambipolar characteristic by electrons transferred from n-type CdSe QDs or holes injected from p-type PbS QDs. The responsivity and detectivity of hybrid BP/0D photo-FETs exhibit 1.16 × 109 A W-1 and 7.53 × 1016 Jones for the BP/CdSe QD photo-FET and 5.36 × 108 A W-1 and 1.89 × 1016 Jones for the BP/PbS QD photo-FET, respectively. The photocurrent rise (τrise) and decay (τdecay) times were τrise = 0.406 s and τdecay = 0.815 s for BP/CdSe QD photo-FET and τrise = 0.576 s and τdecay = 0.773 s for BP/PbS QD photo-FET, respectively.