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A palynological study of genus Dioscorea L. in Korea was conducted to evaluate the taxonomic implications. As a result of confirming the palynological characteristics of seven taxa of Dioscorea L., including six that are distributed in Korea and D. tokoro found in Japan, sections or species were classified according to the characteristics, such as the number of apertures, the polar end shape, and exine sculpturing. Specifically, the exine sculptures of D. coreana and D. tokoro, erroneously known to be distributed in Korea, are distinguished. The change in the number of apertures is closely associated with microsporogenesis, and it can be presumed that disulcate pollen might have been derived from monosulcate pollen in Dioscorea.

Aster altaicus var. uchiyamae, a Korean endemic plant, should be treated as a species rank because it is clearly distinguished from A. altaicus var. altaicus by the morphological characteristics of the plant habit, leaf width, and head size. Nevertheless, when A. altaicus var. uchiyamae was treated as a species rank, the epithet uchiyamae was unavailable in Aster owing to the earlier name A. uchiyamae, which was a replacement name for the illegitimate name A. depauperatus. Therefore, we propose A. danyangensis as a new replacement name for A. altaicus var. uchiyamae. The specific epithet danyangensis refers to the geographic location of Danyang-gun, where the species was discovered. We also designate the lectotype and isolectotype of A. danyangensis.

Seven species and two varieties belonging to the genus Boehmeria Jacq. (Urticaceae) are known to be distributed in Korea. Among them, B. spicata, B. tricuspis, and B. tricuspis var. unicuspis were subjected to an external morphological study. Among the individuals believed to exhibit variations in the leaf shape, B. gracilis and B. silvestrii were newly recognized. Unlike related taxa, B. gracilis has middle leaves with an elliptic, broadly elliptic, ovate, or broadly depressed ovate shape, a regular and serrulate-dentate margin, and an unlobed and short caudate or cuspidate apex. Boehmeria silvestrii has middle leaves with 5-angled ovate, orbicular ovate or broadly ovate shapes, and 3- or 5-lobed and caudate apices. Therefore, we assigned the corresponding names ‘Top-geo-buk-kko-ri’ and ‘Cham-geo-buk-kko-ri’. Meanwhile, the B. spicata complex (B. gracilis, B. silvestrii, B. spicata, and B. tricuspis var. unicuspis) is very closely related in terms of the morphological characters, whereas B. tricuspis exhibits no relationship. Furthermore, because the scientific name and type specimen of B. tricuspis var. unicuspis (Pul-geo-buk-kko-ri) are problematic, the correct name B. paraspicata Nakai and corresponding holotype are presented. Additionally, lectotypes of B. gracilis and B. silvestrii are newly designated here. A taxonomic treatment, descriptions, a key, photographs, type specimens, and leaf variation images of the B. spicata complex are provided in this study.

Polymer dot (PD)-bridged nickel cobalt oxide (NiCo2O4 (NCO)) nanoneedle-assembled globe-shaped clusters for high-performance glucose sensors were prepared via the consecutive calcination and packaging of PDs using the hydrothermal technique. The sp2-conjugated bridge of electrons, abundantly available catechol functionalized active sites offered by the PDs, and porous structure of NCO created effective electron transport routes for electrocatalytic reactions. The remarkable synergy between the conductive PDs and NCO conferred the PDs-bridged NCO (PDs-NCO) exceptional electrocatalytic activity for glucose detection. Under the optimal applied potential of +0.5 V, the developed PDs-NCO-coated Ni foam (NF) electrode presented the broad detection range from 5 μM to 0.25 mM, sensitivity of 806.17 μA mM−1 cm−2, detection limit of 2.75 μM, and exceptional selectivity. Furthermore, the PDs-NCO-coated NF electrode achieved the specific capacitance of 35.63 F g−1 at the current density of 0.5 A g−1 and superb cycling stability including the 96.7% specific capacitance retention over 5000 charge-discharge cycles. In addition, glucose-sensing could be easily monitored using a wireless sensor on a smartphone. The combination of NCO and PDs represents an innovative approach for constructing high-performance, reusable, non-enzymatic glucose sensors with low detection limit, high sensitivity, and excellent selectivity.

We investigated the ocean responses to typhoon Soulik (1819) when it was approaching and landing on the Korean peninsula in August, 2018. During the typhoon passage period, very severe sea surface conditions were recorded such as 15 m of maximum wave height and 35 m/s in gusts, and a 10°C water temperature decrease at the buoy station near Jeju Island. The operational storm surge prediction system of the Korea Meteorological Administration estimated over 50 cm of positive surge near the typhoon center in the approaching stage, and after the typhoon passed, a negative (reverse) storm surge lower than 30 cm was shown off the southern sea of Jeju Island, revealing a cyclonic circulation pattern of the surface water from the satellite altimeter data. According to one-day cycling Argo float observations near the landfall area in the Yellow Sea, temperature and salinity profiles during the typhoon activity showed a sudden deepening of the thermocline and halocline, and then up and down fluctuations between 30–50 m in depth. The temperature decreased by about 2°C in the surface layer and the thermocline layer was deepened by about 10 m from 30 to 40 m in depth while the typhoon was exerting its influence. Salinity in the surface layer showed a sudden change before and after the typhoon, revealing an increase and decrease in 0–15 m and a decrease and increase below 20 m in depth, and the halocline manifested a similar pattern of variation as the thermocline.

Electrochemical water splitting is known as a potential approach for sustainable energy conversion, it produces H2 fuel by utilizing transition metal-based catalysts. We report a facile synthesis of FeCo2O4@carbon dots (CDs) nanoflowers supported on nickel foam through a hydrothermal technique in the absence of organic solvents and an inert environment. The synthesized material with a judicious choice of CDs shows superior performance in hydrogen and oxygen evolution reactions (HER and OER) compared to the FeCo2O4 electrode alone in alkaline media. For HER, the overpotential of 205 mV was able to produce current densities of up to 10 mA cm&minus, 2, whereas an overpotential of 393 mV was needed to obtain a current density of up to 50 mA cm&minus, 2 for OER. The synergistic effect between CDs and FeCo2O4 accounts for the excellent electrocatalytic activity, since CDs offer exposed active sites and subsequently promote the electrochemical reaction by enhancing the electron transfer processes. Hence, this procedure offers an effective approach for constructing metal oxide-integrated CDs as a catalytic support system to improve the performance of electrochemical water splitting.

A tumor microenvironment-responsive wireless strain-pressure hydrogel sensor based on pH-induced controllable nanoparticles was designed for cancer detection in vitro–in vivo model, with excellent ability to distinguish between cancer and normal cells. The pH-responsive nanoparticles (CD-PNB), comprising diol–diol crosslinked semiconducting carbon dots (CDs) and non-conductive polymer (PNB), are sensitive to acidic tumor microenvironments and play crucial role in demonstrating tumor-selective strain-pressure responses. Upon application of strain and pressure, CD-PNB@PVA hydrogel produced distinct electronic signals in the presence of cancer cells (HeLa, PC-3), exhibiting higher strain–pressure sensitivity compared to the normal cells (MDCK, CHO-K1). The strain and pressure gage factors for cancer-cell-treated CD-PNB@PVA hydrogel were found to be 0.7439 and 5.3052 kPa−1, which were higher than normal-cell-treated CD-PNB@PVA hydrogel (0.5009 and 4.2720 kPa−1). CD-PNB@PVA hydrogel demonstrated excellent response in tumor-bearing mice based on in situ and ex situ measurements, with no inflammation during hydrogel implantation. Moreover, wireless sensing system was used along with CD-PNB@PVA hydrogel to simplify monitoring process and obtain real-time conductivity and strain–pressure profiles on smartphone. Thus, this approach constructs a tumor microenvironment-responsive strain–pressure hydrogel sensor and presents potential for sensitive and selective tumor detection in point-of-care diagnostic applications.

Biosensor development for bacterial detection is critical to preventing infectious disease outbreaks caused by bacterial contamination. Recent studies have focused on colorimetric sensors, but high limit of detection (LOD) has restricted their application for sensitive bacterial detection. Here, we designed a reusable, sensitive smartphone-based electrochemical biosensor which uses electroconductive boronic acid-modified polymer dot (B-PD)-coated electrode to detect bacterial contamination. The pH-selective boronic acid in B-PD promotes binding between sensor and bacteria via increased diol-diol kinetics of boronic acid at pH 7.4. B-PD-coated electrodes can detect both gram-negative (E. coli) and gram-positive (S. aureus) bacteria by observing the conductivity change after attachment (101-107 CFU/mL), with high sensitivity, as indicated by low LOD (E. coli=100.8 CFU/mL, S. aureus=101 CFU/mL). The electronic signal from bacterial detection is transmitted to smartphone by connecting B-PD-coated electrode with wireless microcontroller, which allows for simple in-line monitoring. This biosensor demonstrated excellent performance in detecting bacteria in real environmental samples, along with good selectivity towards bacteria, even in the presence of interfering compounds. Moreover, by maintaining boronic acid-diol interaction, B-PD-coated electrode can be reused after applying pH shock (pH