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Agaricales species form pileate-stipitate fruiting bodies and play important roles in maintaining the terrestrial ecosystem as decomposers, symbionts, and pathogens. Approximately 23,000 Agaricales species have been known worldwide, and 937 species have been recorded in the Republic of Korea. However, most of them were identified solely based on morphological characteristics that often led to misidentifications. The specimens collected from 2018 to 2020 in the Republic of Korea were identified based on phylogenetic analysis of the internal transcribed spacer (ITS) sequences. Their identities were confirmed by microscopic characteristics. As a result, 14 Agaricales species were discovered for the first time in the Republic of Korea. They belonged to nine genera

BiVO4 has attracted wide attention for oxygen-evolution photoanodes in water-splitting photoelectrochemical devices. However, its performance is hampered by electron-hole recombination at surface states. Herein, partially oxidized two-dimensional (2D) bismuthene is developed as an effective, stable, functional interlayer between BiVO4 and the archetypal NiFeOOH co-catalyst. Comprehensive (photo)electrochemical and surface photovoltage characterizations show that NiFeOOH can effectively increase the lifetime of photogenerated holes by passivating hole trap states of BiVO4; however, it is limited in influencing electron trap states related to oxygen vacancies (VO). Loading bismuthene on BiVO4 photoanodes increases the density of VO that are beneficial for the oxygen evolution reaction via the formation of oxy/hydroxyl-based water oxidation intermediates at the surface. Moreover, bismuthene increases interfacial band bending and fills the VO-related electron traps, leading to more efficient charge extraction. With the synergistic interaction of bismuthene and NiFeOOH on BiVO4, this composite photoanode achieves a 5.8-fold increase in photocurrent compared to bare BiVO4 reaching a stable 3.4 (±0.2) mA cm–2 at a low bias of +0.8 VRHE or 4.7(±0.2) mA cm–2 at +1.23 VRHE. The use of 2D bismuthene as functional interlayer provides a new strategy to enhance the performance of photoanodes.

호텔 SST는 고객들에게 빠르고 표준화된 서비스를 제공하며 이러한 장점으로 많은 호텔에서 SST를 도입하고 있는 추세이지만 고객측면의 SST에 대한 연구가 희박하다. 이에 본 연구는 UTAUT2를 기반으로 호텔 SST에 대한 사용자의 기술 수용성과 직원-고객 유대관계의 조절효과를 확인하였다. SST 이용고객들을 대상으로 진행된 300개의 설문데이터를 토대로 AMOS 21.0과 SPSS 21.0을 이용하여 실증분석을 진행하였고 분석결과는 다음과 같다. 첫째 성과기대와 노력기대는 유의한 정(+)의 영향을 미쳤다. 둘째, 사회적 영향, 습관 및 촉진조건은 사용의도에 유의한 영향을 미치지 않는 것으로 나타났다. 셋째, 지각된 위험은 유의한 부(-)의 영향을 미치는 것으로 나타났으며 사용의도는 만족에 유의한 정(+)의 영향을 미쳤다. 넷째, 유대관계가 낮은 집단에서는 노력기대와 사용의도 간 유대관계의 조절효과가 유의하게 나타났다. 본 연구는 앞으로 SST를 도입하고자 하는 호텔을 위한 참고자료로 시사점을 제시하였으며 한계점과 향후 연구 방향에 대하여 논의하였다.

Copper(I) thiocyanate (CuSCN) is a stable, low-cost, solution-processable p-type inorganic semiconductor used in numerous optoelectronic applications. Here, for the first time, we employ the time-of-flight (ToF) technique to measure the out-of-plane hole mobility of CuSCN films, enabled by the deposition of 4 μm-thick films using aerosol-assisted chemical vapor deposition (AACVD). A hole mobility of ∼10–3 cm2/V s was measured with a weak electric field dependence of 0.005 cm/V1/2. Additionally, by measuring several 1.5 μm CuSCN films, we show that the mobility is independent of thickness. To further validate the suitability of our AACVD-prepared 1.5 μm-thick CuSCN film in device applications, we demonstrate its incorporation as a hole transport layer (HTL) in methylammonium lead iodide (MAPbI3) perovskite solar cells (PSCs). Our AACVD films result in devices with measured power conversion efficiencies of 10.4%, which compares favorably with devices prepared using spin-coated CuSCN HTLs (12.6%), despite the AACVD HTLs being an order of magnitude thicker than their spin-coated analogues. Improved reproducibility and decreased hysteresis were observed, owing to a combination of excellent film quality, high charge-carrier mobility, and favorable interface energetics. In addition to providing a fundamental insight into charge-carrier mobility in CuSCN, our work highlights the AACVD methodology as a scalable, versatile tool suitable for film deposition for use in optoelectronic devices.

This paper presents a systematic approach of high-frequency electrical properties of embroidered dipole-type antennas based on electro-textiles. Firstly, characterizations of conductive thread and silver ink on cotton fabric are completed by UTM (Universal testing machine) and sheet resistance measurement. Secondly, estimating and optimizing the embroidered dipole antenna suitable for implementing radio frequency identification (RFID) tags are proposed. The effect of bending and thread density on the performance of embroidered antennas is included. Thirdly, the proposed low-cost antenna structure requires the less conductive thread to decrease conductive thread and time consumption yet still achieve good enough performance compared with the conventional antenna. Finally, the comparison between silver thread and ink demonstrates that parasitic capacitance of conductive threads is much higher than metallic materials. However, the structure of silver conductive threads has more potential to significantly improve the conductor’s efficiency than silver ink at the high frequencies.

Π-conjugated polymers (π-CPs) blended with ionic liquids (ILs) have shown great potential for noninvasive diagnostics by transducing dielectric environmental changes induced by volatile organic com...

Incisional hernia (IH) is a commonly encountered problem even in the era of minimally invasive surgery (MIS). Numerous studies on IH are available in English literature, but there are lack of data from the Eastern part of the world. This study aimed to evaluate the risk factors as well as incidence of IH by analyzing a large cohort collected from a single tertiary center in Korea. Among a total number of 4276 colorectal cancer patients who underwent a surgical resection from 2006 to 2019 in Korea University Anam Hospital, 2704 patients (2200 laparoscopic and 504 robotic) who met the inclusion criteria were analyzed. IH was confirmed by each patient’s diagnosis code registered in the hospital databank based on physical examination and/or computed tomography findings. Clinical data including specimen extraction incision (transverse or vertical midline) were compared between IH group and no IH group. Risk factors of developing IH were assessed by utilizing univariable and multivariable analyses. During the median follow-up of 41 months, 73 patients (2.7%) developed IH. Midline incision group (n = 1472) had a higher incidence of IH than that of transverse incision group (n = 1232) (3.5% vs. 1.7%, p = 0.003). The univariable analysis revealed that the risk factors of developing IH were old age, female gender, obesity, co-morbid cardiovascular disease, transverse incision for specimen extraction, and perioperative bleeding requiring transfusion. However, on multivariable analysis, specimen extraction site was not significant in developing IH and transfusion requirement was the strongest risk factor. IH development after MIS is uncommon in Korean patients. Multivariable analysis suggests that specimen extraction site can be flexibly chosen between midline and transverse incisions, with little concern about risk of developing IH. Careful efforts are required to minimize operative bleeding because blood transfusion is a strong risk factor for developing IH.

Reported here is a new high electron affinity acceptor end group for organic semiconductors, 2,1,3‐benzothiadiazole‐4,5,6‐tricarbonitrile (TCNBT). An n‐type organic semiconductor with an indacenodithiophene (IDT) core and TCNBT end groups was synthesized by a sixfold nucleophilic substitution with cyanide on a fluorinated precursor, itself prepared by a direct arylation approach. This one‐step chemical modification significantly impacted the molecular properties: the fluorinated precursor, TFBT IDT, a poor ambipolar semiconductor, was converted into TCNBT IDT, a good n‐type semiconductor. The electron‐deficient end group TCNBT dramatically decreased the energy of the highest occupied and lowest unoccupied molecular orbitals (HOMO/LUMO) compared to the fluorinated analogue and improved the molecular orientation when utilized in n‐type organic field‐effect transistors (OFETs). Solution‐processed OFETs based on TCNBT IDT exhibited a charge‐carrier mobility of up to μ e≈0.15 cm2 V−1 s−1 with excellent ambient stability for 100 hours, highlighting the benefits of the cyanated end group and the synthetic approach., A new strongly electron‐accepting end group, 2,1,3‐benzothiadiazole‐4,5,6‐tricarbonitrile (TCNBT), has been prepared by a one‐step sixfold nucleophilic substitution reaction. Cyanation results in a significant enhancement of the electron affinity in comparison to the fluorinated analogue, and the material demonstrates promising n‐type performance in solution processed organic field‐effect transistors with excellent stability.

Amine-containing polyelectrolytes such as polyethyleneimine (PEI) are commonly used as cathode interfacial materials (CIMs); however, they are rarely found in non-fullerene acceptor (NFA) organic solar cells due to undesirable chemical reactions between PEI and NFAs. Unveiling the nature of these chemical interactions and developing chemically stable amine-containing polyelectrolytes is inevitable for achieving highly efficient and stable NFA organic solar cells. Herein, the reaction between PEI and 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (INCN)-based NFAs was investigated using a model system. 15N-isotope labeling experiments and 2D nuclear magnetic resonance (NMR) studies revealed that the products were generated by the Michael addition reaction and existed as the keto–enol tautomers. Based on the identified undesirable reaction, we developed a series of functionalized PEIs that are compatible with INCN-based NFAs by protecting the reactive amine functional groups. Highly efficient and stable NFA organic solar cells were successfully fabricated by the use of functionalized PEIs with broad work function tunability and improved chemical stability, which led to NFA organic solar cells with high power conversion efficiency (PCE) values of over 15% and thermally stable device operation for more than 360 hours at 100 °C.

Semiconducting polymers with oligoethylene glycol sidechains have attracted strong research interest for organic electrochemical transistor (OECT) applications. However, key molecular design rules for high-performance OECTs via efficient mixed electronic/ionic charge transport are still unclear. Herein, we synthesize and characterize new glycolated copolymers (gDPP-TTT and gDPP-TTVTT) with diketopyrrolopyrrole (DPP) acceptor and thiophene-based (TTT or TTVTT) donor units for accumulation mode OECTs, where a long-alkyl-group (C12 ) attached to DPP unit acts as a spacer distancing the oligoethylene glycol from the polymer backbone. gDPP-TTVTT shows the highest OECT transconductance (61.9 S cm-1 ) and high operational stability, compared to gDPP-TTT and their alkylated counterparts. Surprisingly, gDPP-TTVTT also shows high electronic charge mobility in field-effect transistor, suggesting efficient ion injection/diffusion without hindering its efficient electronic charge transport. The elongated donor unit (TTVTT) facilitates the hole polaron formation more localized to the donor unit, leading to faster and easier polaron formation with less impact on polymer structure during OECT operation, as opposed to the TTT unit. This is supported by molecular dynamics (MD) simulation. We conclude that these simultaneously high electronic and ionic charge transport properties are achieved due to the long-alkyl-group spacer in amphipathic sidechains, providing an important molecular design rule for glycolated copolymers. This article is protected by copyright. All rights reserved.

Background Lateral pelvic lymph node dissection has been performed selectively in rectal cancer cases; however, it involves highly skilled techniques because of the complex adjacent anatomical structures. Materials and Methods Laparoscopic EP-LPND was performed in Korea University Anam Hospital from June 2018, and short-term surgical outcomes were analyzed from June to December 2018. Among the patients with histologically diagnosed rectal adenocarcinoma, patients who were suspected Lateral pelvic lymph node metastasis at magnetic resonance imaging were selected for this procedure. Results Seven patients underwent laparoscopic extraperitoneal approach for lateral pelvic lymph node dissection in the study period. The mean number of retrieved lymph node was 4.57, and metastatic lymph nodes were identified in 3 patients (42.8%). All of the lymph nodes with suspected metastasis preoperatively were removed in postoperative images. There was no immediate postoperative complication beyond the moderate grade associated with lateral pelvic lymph node dissection. The median follow-up was 9 months, and there were no local recurrence nor complications related to sexual and voiding functions. Conclusions The laparoscopic extraperitoneal approach might be an efficient way to perform lateral pelvic lymph node dissection using the same principles as the conventional method without violation of the peritoneum.

Recent developments of solution-processed bulk-heterojunction organic photovoltaic (OPV) cells have demonstrated power conversion efficiencies (PCEs) as high as 18% for single-junction devices. Such a high PCE in addition to its desirable lightweight property and high mechanical flexibility can realize high specific power and small stowed volume, which are key considerations when choosing PV for space missions. To take one important step forward, their resilience to ionizing radiation should be well studied. Herein, the effect of proton irradiation at various fluences on the performance of benchmark OPV cells is explored under AM0 illumination. The remaining device performance is found to decrease with increasing proton fluence, which correlates to changes in electrical and chemical properties of the active layer. By redissolving the devices, the solubility of the active layer is found to decrease with increasing proton fluence, suggesting that the active materials are likely cross-linked. Additionally, Raman studies reveal conformational changes of the polymer leading to a higher degree of energetic disorder. Despite a drop in performance, the retaining percentage of the performance is indeed higher than the current market-dominating space PV technology—III–V semiconductor-based PV, demonstrating a high potential of the OPV cell as a candidate for space applications

Poly(9,9-dioctylfluorene) (PFO) is one of the most important conjugated polymer materials, exhibiting outstanding photophysical and electrical properties. PFO is also known for a diversity of morphological phases determined by conformational states of the main chain. Our goal in this work is to address some of the key questions on formation and dynamics of one such conformation, the β-phase, by following in real time the evolution of fluorescence spectra of single PFO chains. The PFO is dispersed in a thin polystyrene film, and the spectra are monitored during the process of solvent vapor annealing with toluene. We confirm unambiguously that the PFO β-phase segments are formed on a true single-chain level at room temperature in the solvent-softened polystyrene. We further find that the formation of the β-phase is a dynamic and reversible process occurring on the order of seconds, leading to repeated spontaneous transitions between the glassy and β-phase segments during the annealing. Comparison of PFO with two largely different molecular weights (Mw) shows that chains with lower Mw form the β-phase segments much faster. For the high Mw PFO chains, a detailed Franck-Condon analysis of the β-phase spectra shows a large distribution of the Huang-Rhys factor, S, and even dynamic changes of this factor occurring on a single chain. Such dynamics are likely a manifestation of changing coherence length of the exciton. Further, for the high Mw PFO chains we observe an additional conformational state, a crystalline γ-phase. The γ-phase formation is also a spontaneous reversible process in the solvent-softened matrix. The phase can form from both the β-phase and the glassy phase, and the formation requires high Mw to enable intersegment interactions in a self-folded chain.

Penicillium in section Exilicaulis is characterized by non-vesiculate monoverticillate and biverticillate stipes. Species in sect. Exilicaulis are commonly found in soil and plants in terrestrial environments; however, only a few species have been reported in Korea. To investigate the diversity of Penicillium sect. Exilicaulis, Penicillium species were isolated from terrestrial and marine environments. Based on sequence analyses of β-tubulin, calmodulin, and the second largest subunit of RNA polymerase II loci, 19 strains of Penicillium in sect. Exilicaulis were identified as P. citreonigrum, P. citreosulfuratum, P. corylophilum, P. menonorum, P. rubefaciens, P. velutinum, Penicillium sp. 1, and Penicillium sp. 2. Two of them, P. citreonigrum and P. citreosulfuratum, were confirmed to be new to Korea. Molecular phylogenies and detailed descriptions of the two unrecorded species are provided.

The medical fitness of pilots is part of the civil aviation safety scenery. This study aimed to analyze the health problems occurring among Korean commercial pilots. Three data sources were used to identify the health problems: 7,574 aviation medical examination data, 5,400 sick leaves and 39 cases of a decrease in medical fitness during flight duty period and layover of Korean commercial pilots who have been working for K airline from Jan. 1, 2016 to Dec. 31, 2018. This study was retrospectively analyzed using SPSS 22 statistical program. Waiver of medical certificates was an average 11.9% of total issuance for 3 years, with a denial of 0.1%. The leading cause of denial of medical certificates was predominantly of cardiovascular cause (55.6%). Mild respiratory and digestive disease accounted for 82% of total sick prevalence and 68% of total sick days. The psychiatric and cardiovascular disease were ranked high according to the number of days lost per case. The most common cause of decrease in medical fitness during flight duty period was acute abdominal pain (36.4%) and musculoskeletal disorder (40%) when staying abroad. Aeromedical emphasis on minimizing cardiovascular risk remains appropriate. Major pilot health problems identified in this study should be considered in establishing pilot health promotion programs for aviation safety.

Osteoporosis is a skeletal disease characterized by bone loss and bone microarchitectural deterioration. The combination of smart materials and stem cells represents a new therapeutic approach. In the present study, highly porous scaffolds are prepared by combining the conducting polymer PEDOT:PSS with collagen type I, the most abundant protein in bone. The inclusion of collagen proves to be an effective way to modulate their mechanical properties and it induces an increase in scaffolds’ electrochemical impedance. The biomimetic scaffolds support neural crest-derived stem cell osteogenic differentiation, with no need for scaffold pre-conditioning contrarily to other reports.

Low-Density Polyethylene (LDPE) was synthesized from ethylene at high-temperature and pressure condition. Hyper-compressor used to increase pressure up to 3,500 atm should be monitored and controlled delicately or it cannot guarantee stable operation of the process causing process shutdown (SD), which is directly related to product yield and process safety. This paper presents a data-based multivariate statistical monitoring method to detect anomalies in the hyper-compressor of a LDPE manufacturing process with weighted principal component analysis model (WPCA), which can consider both time-varying and time-invariant characteristic of data combining principal component analysis (PCA) and slow feature analysis (SFA). Operation data of the LDPE manufacturing process was gathered hourly for four years. WPCA-based principal component control limit (PCCL) was used as an index to determine anomaly and applied to five emergency shutdown (ESD) cases, respectively. As a result, all the five anomalies were detected by a PCCL, respectively, as a sign of SD. Moreover, it shows a better anomaly detection performance than the monitoring method using T2 and squared prediction error (SPE) based on PCA, SFA, or WPCA.

Electric-field driven chemical doping modulation in a blend of solution-processed organic semiconductors (OSCs) and solid-state ionic liquids (SSILs) in response to volatile organic compounds (VOCs) provides a new exciting opportunity to facilitate printable and low-power chemical gas sensors (chemiresistors). In order to fully exploit this opportunity, a fundamental understanding of the molecular-level interactions among the OSCs, SSILs, and VOC components during the device operation is urgently needed. Herein, we demonstrate a highly sensitive and selective VOC gas sensor using π-conjugated polymer (here, P3HT as a model homopolymer) and SSIL blends. A newly developed SSIL forms a semi-crystalline solid at room temperature. P3HT with high molecular weight and regioregularity allows an extremely well-interconnected network in blends desirable for efficient charge transport. In P3HT:SSIL blends, we identify electric-field driven strong chemical interactions between π-CP and SSIL to tune the electrical conductivity of the π-CP. The enlarged interfacial areas in blends and the solid-state nature of the SSIL ensure highly tunable electrochemical interactions between them, efficiently modulating the electrical conductivity of the π-CP further upon exposure to different polar and non-polar VOCs. Our results demonstrate the π-conjugated polymer/SSIL complex as a new highly sensitive and selective gas sensor and provide a key scientific understanding of its molecular-level operational mechanism critical for developing molecular sensors towards next generation noninvasive diagnostics.

Printable organic sensors fabricated from solution-processed π-conjugated polymers (π-CPs) are promising candidates to detect volatile organic compounds (VOCs) due to the intriguing physical, chemical and electronic properties of π-CPs. These devices, often termed organic chemiresistors, require good sensing capabilities to transduce stimuli from specific VOCs at low concentrations into analytical electric signals. However, discriminating such VOCs using organic chemiresistors has proven very challenging. Herein, we report that the molecular-level electrochemical doping of π-CPs with solid-state ionic liquids (SILs) significantly improves their electrical conductivity (∼10−1 S cm−1) and selective VOC interactions, which can be manipulated through different π-CPs:SIL blend ratios. These characteristics enable the fine discrimination of VOCs at concentrations in the parts-per-billion (ppb) range under low power consumption (

An effective strategy to engineer selective photodynamic agents to surmount bacterial-infected diseases, especially Gram-positive bacteria remains a great challenge. Herein, we developed two examples of compounds for a proof-of-concept study where reactive differences in reactive oxygen species (ROS) can induce selective ablation of Gram-positive bacteria. Sulfur-replaced phenoxazinium (NBS-N) mainly generates a superoxide anion radical capable of selectively killing Gram-positive bacteria, while selenium-substituted phenoxazinium (NBSe-N) has a higher generation of singlet oxygen that can kill both Gram-positive and Gram-negative bacteria. This difference was further evidenced by bacterial fluorescence imaging and morphological changes. Moreover, NBS-N can also successfully heal the Gram-positive bacteria-infected wounds in mice. We believe that such reactive differences may pave a general way to design selective photodynamic agents for ablating Gram-positive bacteria-infected diseases.

Collybiopsis is a genus of the gymnopoid/marasmioid complex of the family Omphalotaceae. The classification system of Collybiopsis has recently undergone large changes through molecular approaches. The new classification system has not been applied for Collybiopsis in the Republic of Korea, and general research on this genus was also lacking. In this study, we analyzed the Collybiopsis species in the Republic of Korea by assessing all gymnopoid/marasmioid specimens collected nationwide for ten years by combining morphological approaches and multilocus (ITS + nrLSU) phylogenetic analysis. We thus confirmed that 16 species of Collybiopsis are present in the Republic of Korea, including two previously unreported species (Co. nonnulla and Co. dichroa) and seven new species (Co. albicantipessp. nov., Co. clavicystidiatasp. nov., Co. fulvasp. nov., Co. orientisubnudasp. nov., Co. subumbilicatasp. nov., Co. undulatasp. nov., and Co. vellereasp. nov.). A thorough examination of the Collybiopsis suggested that it is difficult to distinguish or identify the species based on morphological characteristics only; a combined molecular approach is needed for accurate identification. The Collybiopsis database of the Republic of Korea is updated, and information on the new species is provided. Five new combinations from Marasmiellus to Collybiopsis are also proposed (Co. istanbulensiscomb. nov., Co. koreanacomb. nov., Co. omphalodescomb. nov., Co. pseudomphalodescomb. nov., and Co. ramuliciolacomb. nov.).

The textile industry has advanced processes that allow computerized manufacturing of garments at large volumes with precise visual patterns. The industry, however, is not able to mass fabricate clothes with seamlessly integrated wearable sensors, using its precise methods of fabrication (such as computerized embroidery). This is due to the lack of conductive threads compatible with standard manufacturing methods used in industry. In this work, we report a low-cost poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)-modified cotton conductive thread (PECOTEX) that is compatible with computerized embroidery. The PECOTEX was produced using a crosslinking reaction between PEDOT:PSS and cotton thread using divinyl sulfone as the crosslinker. We extensively characterized and optimized our formulations to create a mechanically robust conductive thread that can be produced in large quantities in a roll-to-roll fashion. Using PECOTEX and a domestic computerized embroidery machine, we produced a series of wearable electrical sensors including a facemask for monitoring breathing, a t-shirt for monitoring heart activity and textile-based gas sensors for monitoring ammonia as technology demonstrators. PECOTEX has the potential to enable mass manufacturing of new classes of low-cost wearable sensors integrated into everyday clothes.

The bimolecular recombination characteristics of conjugated polymer poly[(4,4′-bis(2-ethylhexyl)dithieno[3,2-b:2′,3′-d]silole)-2,6-diyl-alt-(2,5-bis 3-tetradecylthiophen-2-yl thiazolo 5,4-d thiazole)-2,5diyl] (PDTSiTTz) blended with the fullerene series PC60BM, ICMA, ICBA, and ICTA have been investigated using microsecond and femtosecond transient absorption spectroscopy, in conjunction with electroluminescence measurements and ambient photoemission spectroscopy. The non-Langevin polymer PDTSiTTz allows an inspection of intrinsic bimolecular recombination rates uninhibited by diffusion, while the low oscillator strengths of fullerenes allow polymer features to dominate, and we compare our results to those of the well-known polymer Si-PCPDTBT. Using μs-TAS, we have shown that the trap-limited decay dynamics of the PDTSiTTz polaron becomes progressively slower across the fullerene series, while those of Si-PCPDTBT are invariant. Electroluminescence measurements showed an unusual double peak in pristine PDTSiTTz, attributed to a low energy intragap charge transfer state, likely interchain in nature. Furthermore, while the pristine PDTSiTTz showed a broad, low-intensity density of states, the ICBA and ICTA blends presented a virtually identical DOS to Si-PCPDTBT and its blends. This has been attributed to a shift from a delocalized, interchain highest occupied molecular orbital (HOMO) in the pristine material to a dithienosilole-centered HOMO in the blends, likely a result of the bulky fullerenes increasing interchain separation. This HOMO localization had a side effect of progressively shifting the polymer HOMO to shallower energies, which was correlated with the observed decrease in bimolecular recombination rate and increased “trap” depth. However, since the density of tail states remained the same, this suggests that the traditional viewpoint of “trapping” being dominated by tail states may not encompass the full picture and that the breadth of the DOS may also have a strong influence on bimolecular recombination.

With the rapid development of perovskite solar cells, reducing losses in open-circuit voltage (Voc) is a key issue in efforts to further improve device performance. Here it is focused on investigating the correlation between the highest occupied molecular orbital (HOMO) of device hole transport layers (HTLs) and device Voc. To achieve this, structurally similar HTL materials with comparable optical band gaps and doping levels, but distinctly different HOMO levels are employed. Using light-intensity dependent Voc and photoluminescence measurements significant differences in the behavior of devices employing the two HTLs are highlighted. Light-induced increase of quasi-Fermi level splitting (ΔEF) in the perovskite layer results in interfacial quasi-Fermi level bending required to align with the HOMO level of the HTL, resulting in the Voc measured at the contacts being smaller than the ΔEF in the perovskite. It is concluded that minimizing the energetic offset between HTLs and the perovskite active layer is of great importance to reduce non-radiative recombination losses in perovskite solar cells with high Voc values that approach the radiative limit.

Genus Xylodon consists of white-rot fungi that grow on both angiosperms and gymnosperms. With resupinate and adnate basidiomes, Xylodon species have been classified into other resupinate genera for a long time. Upon the integration of molecular assessments, the taxonomy of the genus has been revised multiple times over the years. However, the emendations were poorly reflected in studies and public sequence databases. In the present study, the genus Xylodon in Korea was evaluated using molecular and morphological analyses of 172 specimens collected in the period of 2011 to 2018. The host types and geographical distributions were also determined for species delimitation. Furthermore, public sequences that correspond to the Xylodon species in Korea were assessed to validate their identities. Nine Xylodon species were identified in Korea, with three species new to the country. Morphological differentiation and identification of some species were challenging, but all nine species were clearly divided into well-resolved clades in the phylogenetic analyses. Detailed species descriptions, phylogeny, and a key to Xylodon species in Korea are provided in the present study. A total of 646 public ITS and nrLSU sequences corresponding to the nine Xylodon species were found, each with 404 (73.1%) and 57 (61.3%) misidentified or labeled with synonymous names. In many cases, sequences released before the report of new names have not been revised or updated. Revisions of these sequences are arranged in the present study. These amendments may be used to avoid the misidentification of future sequence-based identifications and concurrently prevent the accumulation of misidentified sequences in GenBank.

The development of non-fullerene acceptors (NFAs) has facilitated the realization of efficient organic solar cells (OSCs) with minimal burn-in losses and excellent long-term stability. However, the role of NFA molecular structures on device stability remains unclear, limiting commercialization of NFA-based OSCs. Herein, the photostability of 10 OSC devices, fabricated with various NFAs (O-IDTBR, EH-IDTBR, ITIC, and ITIC-M) blended with donor polymers (PTB7-Th, PffBT4T-2OD, and PBDB-T), is investigated. O-IDTBR and EH-IDTBR form highly stable devices with all three polymers, whereas ITIC and ITIC-M devices suffer from burn-in losses and long-term degradation. Conformational instability is found to be responsible for the poor photostability of ITIC and ITIC-M, resulting in poor device stability. Twisting and potential breakage of the chemical bond that links the end group to the main backbone of ITIC and ITIC-M molecules causes undesirable conformational changes. Potential strategies to overcome such detrimental photo-induced conformational changes in NFAs are proposed. Funding Agencies|European Social Fund via the Welsh Government; EPSRCUK Research & Innovation (UKRI)Engineering & Physical Sciences Research Council (EPSRC) [EP/L015099/1, EP/T026219/1, EP/S020748/1]; UK EPSRCUK Research & Innovation (UKRI)Engineering & Physical Sciences Research Council (EPSRC) [EP/L016702/1]; ATIP Programme grant [EP/T028513/1]; CSEM Brasil; Global Research Laboratory Program of the National Research Foundation (NRF) - Ministry of Science, ICT & Future Planning [NRF-2017K1A1A2013153]; UKRI Global Challenge Research Fund project, SUNRISE [EP/P032591/1]; Office of Sponsored Research (OSR) [OSR-2018-CRG/CCF-3079, OSR-2019-CRG8-4086, OSR-2018-CRG7-3749]; European Social Fund, European Union CSEM Brasil, Brazil European Research Council, European Union ERC Synergy Grant [SC2 (610115)]; European Unions Horizon 2020 research and innovation programme [952911]; project BOOSTER [862474]; project RoLA-FLEX; KAUSTKing Abdullah University of Science & Technology

Purpose: Colorectal cancer (CRC) occurs in all age groups, and the application of treatment may vary according to age. The study was designed to identify the characteristics of CRC by age.Methods: A total of 4,326 patients undergoing primary resection for CRC from September 2006 to July 2019 were reviewed. Patient and tumor characteristics, operative and postoperative data, and oncologic outcome were comparedResults: Patients aged 60 to 69 years comprised the largest age group (29.7%), followed by those aged 50 to 59 and 70 to 79 (24.5% and 23.9%, respectively). Rectal cancer was common in all age groups, but right-sided colon cancer tended to be more frequent in older patients. In very elderly patients, there were significant numbers of emergency surgeries, and the frequencies of open surgery and permanent stoma were greater. In contrast, total abdominal colectomy or total proctocolectomy was performed frequently in patients in their teens and twenties. The elderly patients showed more advanced tumor stages and postoperative ileus. The incidence of adjuvant treatment was low in elderly patients, who also had shorter follow-up periods. Overall survival was reduced in older patients with stages 0 to 3 CRC (P

We report a method of creating solderable, mechanically robust, electrical contacts to interface (soft) silicone-based strain sensors with conventional (hard) solid-state electronics using a nanoporous Si-Cu composite. The Si-based solder-on electrical contact consists of a copper-plated nanoporous Si top surface formed through metal-assisted chemical etching and electroplating, and a smooth Si bottom surface which can be covalently bonded onto silicone-based strain sensors through plasma bonding. We investigated the mechanical and electrical properties of the contacts proposed under relevant ranges of mechanical stress for applications in physiological monitoring and rehabilitation. We also produced a series of proof-of-concept devices, including a wearable respiration monitor, leg band for exercise monitoring and Squeeze-ball for monitoring rehabilitation of patients with hand injuries or neurological disorders, to demonstrate the mechanical robustness and versatility of the technology developed, in real-world applications.

Nanomaterials with enzyme-like characteristics (nanozymes) have emerged as potential replacements for natural enzymes due to their potential to overcome several critical limitations of natural enzymes, including low stability as well as high costs in preparation and purification. Herein, we have developed hybrid nanostructures that incorporate cobalt oxide nanoparticles (Co₃O₄ NPs) and gold nanoclusters (AuNCs) through electrostatic attraction induced by simple incubation in an aqueous buffer for 2 hours. Owing to the synergistic effect of Co₃O₄ NPs and AuNCs, the constructed Co₃O₄/Au hybrid nanostructures yielded highly enhanced peroxidase-like activity and enabled rapid catalytic oxidation of a chromogenic substrate, 3,3',5,5'-tetramethylbenzidine (TMB), producing a blue colored solution depending on the amount of H₂O₂. Moreover, we observed catalytic activity of the Co₃O₄/Au hybrid over a broad pH range, especially at physiologically relevant pH in the range of 5.0-7.4, which is advantageous for applications in biological systems. Using the hybrid as peroxidase mimic, we successfully determined the level of target H₂O₂ or glucose by coupling with glucose oxidase with excellent specificity and sensitivity. Based on this study, we expect that Co₃O₄/Au hybrid nanostructures can serve as potent peroxidase mimics for the detection of clinically important target molecules.

Lysosomes, an important organelle of eukaryotic cells, are covered with the cell membrane and contain an array of degradative enzymes. The disrupt in lysosomal functions may lead to the development of severe diseases. In nanotechnology, nanomaterials working mechanism and its biomedical output are highly dependent on the lysosomes as it plays a crucial role in intracellular transport. Several nanomaterials specifically designed for lysosome-related actions are highly advantageous in trafficking and delivering the loaded imaging/therapeutic agents. But for other applications, especially gene-based therapeutic delivery into the sub-organelles such as mitochondria and nucleus, lysosomal related degradation could be an obstacle to achieve a maximal therapeutic index. In order to understand the relationship between lysosomes and designed nanomaterials for kind of desired application in biomedical research, complete knowledge of their various designing strategies, size dependent or ligand supportive cellular uptake mechanisms, trafficking, and localizations in eukaryotic cells is highly desired. In this review, we intended to discuss various nanomaterial types that have been applied in biomedical applications based on lysosomal internalization and escape from endo/lysosomes and explored their related advantages/disadvantages. Additionally, we also deliberated nanomaterials direct translocation mechanism, their autophagic accumulation and the underlying mechanism to induced autophagy. Finally, some challenges and critical issues in current research from clinical application perspective has also been addressed. Great understanding of these factors will help in understanding and facilitating the development of safe and effective lysosomal related nanomaterial-based imaging/therapeutic systems for future applications.

Summary Studying the ultra-fine structure and functions of mitochondria at a nanoscale level has garnered tremendous attention from biologists. Mitochondria perform many more functions than merely generating adenosine triphosphate (ATP), and their functions can vary in different eukaryotic cells. In place of diffraction-limited conventional imaging techniques, advanced nanoscopic technologies have been devised in the past decades to explore the unknown aspects of mitochondrial dynamics and complex structures with a sub-diffraction resolution. The success of these super-resolution microscopy and nanoscopy techniques is complemented by the advancements in designing smart fluorescent probes that target mitochondria. Therefore, this review includes the comprehensive aspects of the recent progress in developing fluorogenic systems for nanoscopic imaging of mitochondria. The review also critically assesses the associated benefits and limitations of such fluorophores when they are employed in practical experiments. Future scope and challenges in developing suitable fluorophores for several nanoscopic techniques are also judiciously evaluated.

Several studies have suggested that shell colour may be phylogenetically distributed within the phylum Mollusca, but this pattern is confounded by our ignorance of the homology of colour and lack of understanding about the identity of most molluscan pigments. We use resonance Raman spectroscopy to address this problem by examining bivalve pigments producing a range of colours and compare spectra from taxa at different phylogenetic levels. The spectra of most shell pigments exhibited a skeletal signature typical of partially methylated polyenes, possibly modified carotenoids, with the strongest peaks occurring between 1,501–1,540 cm−1 and 1,117–1,144 cm−1 due to the C═C (ν1) and C–C (ν2) stretching modes, respectively. Neither pigment class nor mineral structure differentiated Imparidentia and Pteriomorphia. Spectral acquisitions for purple pigments for two species of Asaphis suggest that identical or nearly identical pigments are shared within this genus, and some red pigments from distantly related species have similar spectra. Conversely, two species with brown shells have distinctly different pigments, highlighting the difficulty in determining the homology of colour even within a single class of pigments. Curiously, we were unable to detect any Raman activity for green‐coloured shell or pigment peaks for the yellow area of Codakia paytenorum, suggesting that these colours are due to structural elements or a pigment that is quite different from those observed in other taxa examined to date. Our results are consistent with the idea that classes of pigments are evolutionarily ancient but heritable modifications may be specific to clades.

Bone-resorbing osteoclasts are differentiated from macrophages (MΦ) by M-CSF and RANKL. MΦ can be mainly classified into M1 and M2 MΦ, which are proinflammatory and anti-inflammatory, respectively, but little is known about their osteoclastogenic potential. Here, we investigated the osteoclastogenic potential of MΦ subtypes. When the two MΦ subtypes were differentiated into osteoclasts using M-CSF and RANKL, M2 MΦ more potently differentiated into osteoclasts than M1 MΦ. M2 MΦ generated with IL-4 or IL-10 also showed enhanced osteoclast differentiation compared with M1 MΦ induced by IFN-γ and lipopolysaccharide. In addition, robust bone-resorptive capacity and giant actin rings, which are features of mature osteoclasts, were observed in M2, but not M1 MΦ, under the osteoclast differentiation condition. Osteoclast differentiation was significantly increased in CD206+ M2 MΦ but not in CD86+ M1 MΦ. Compared with M1 MΦ, c-Fms and RANK were highly expressed in M2 MΦ. Enhanced osteoclastogenesis of M2 MΦ was mediated through sustained ERK activation, followed by efficient c-Fos and NFATc1 induction. Notably, the osteoclastogenic potential of M1 MΦ converted into M2 MΦ by exposure to M-CSF was higher than that of M2 MΦ converted into M1 MΦ by exposure to GM-CSF. Silencing IRF5, which is responsible for M1 MΦ polarization, increased osteoclast differentiation by enhancing c-Fms expression and activation of ERK, c-Fos, CREB, and NFATc1, which was inhibited by overexpression of IRF5. Collectively, M2 MΦ are suggested to be more efficient osteoclast precursors than M1 MΦ because of the attenuated expression of IRF5.

Cyclic dinucleotides (CDNs), such as cyclic diadenylate monophosphate and cyclic diguanylate monophosphate, are commensal bacteria-derived second messengers in the gut that modulate bacterial survival, colonization, and biofilm formation. Recently, CDNs have been discovered to have an immunomodulatory activity by inducing the expression of type I interferon (IFN) through STING signaling pathway in macrophages. Because CDNs are possibly absorbed and delivered into the bone marrow, where bone-resorbing osteoclasts are derived from monocyte/macrophage lineages, CDNs could affect bone metabolism by regulating osteoclast differentiation. In this study, we investigated the effect of CDNs on the differentiation and function of osteoclasts and osteoblasts. When bone marrow-derived macrophages (BMMs) were differentiated into osteoclasts with macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL) in the presence of CDNs, the differentiation was inhibited by CDNs in a dose-dependent manner. In contrast, CDNs did not influence the differentiation of committed osteoclasts or osteoblast precursors. STING signaling pathway appeared to be critical for CDNs-mediated inhibition of osteoclast differentiation since CDNs induced the phosphorylation of TBK1 and IRF3, a representative feature of STING activation, and osteoclast differentiation was restored in STING knockdown BMMs with siRNA. Moreover, CDNs increased the mRNA expression of STING-meditated IFN-β, which is a negative regulator of osteoclastogenesis. In addition, CDNs also induced the phosphorylation of STAT1, which mediates IFN-α/β receptor (IFNAR) signal transduction. The inhibitory effects of CDNs on osteoclast differentiation were not observed in the presence of antibody blocking IFNAR or in macrophages derived from IFNAR1-/- mice. Experiments using a mouse calvarial implantation model showed that RANKL-induced bone resorption was inhibited by CDNs. Taken together, these results suggest that CDNs inhibit osteoclast differentiation and bone resorption through induction of IFN-β via the STING signaling pathway. © 2019 American Society for Bone and Mineral Research.

Doping is a widely implemented strategy for enhancing the inherent electronic properties of charge transport layers in photovoltaic (PV) devices. Here, in direct contrast to existing understanding, we find that a reduction in p-doping of the organic hole transport layer (HTL) leads to substantial improvements in PV performance in planar p–i–n perovskite solar cells (PSCs), driven by improvements in open circuit voltage (VOC). Employing a range of transient and steady state characterisation tools, we find that the improvements of VOC correlate with reduced surface recombination losses in less p-doped HTLs. A simple device model including screening of bulk electric fields in the perovskite layer is used to explain this observation. In particular, photoluminescence (PL) emission of complete solar cells shows that efficient performance is correlated to a high PL intensity at open circuit and a low PL intensity at short circuit. We conclude that desirable transport layers for p–i–n PSCs should be charge selective contacts with low doping densities.

Streptococcus gordonii is commonly found in the periapical endodontic lesions of patients with apical periodontitis, a condition characterized by inflammation and periapical bone loss. Since bone metabolism is controlled by osteoclastic bone resorption and osteoblastic bone formation, we investigated the effects of S. gordonii on the differentiation and function of osteoclasts and osteoblasts. For the determination of bone resorption activity in vivo, collagen sheets soaked with heat-killed S. gordonii were implanted on mouse calvaria, and the calvarial bones were scanned by micro-computed tomography. Mouse bone marrow-derived macrophages (BMMs) were stimulated with M-CSF and RANKL for 2 days and then differentiated into osteoclasts in the presence or absence of heat-killed S. gordonii. Tartrate-resistant acid phosphatase staining was performed to determine osteoclast differentiation. Primary osteoblast precursors were differentiated into osteoblasts with ascorbic acid and β-glycerophosphate in the presence or absence of heat-killed S. gordonii. Alkaline phosphatase staining and alizarin red S staining were conducted to determine osteoblast differentiation. Western blotting was performed to examine the expression of transcription factors including c-Fos, NFATc1, and Runx2. Heat-killed S. gordonii induced bone destruction in a mouse calvarial implantation model. The differentiation of RANKL-primed BMMs into osteoclasts was enhanced in the presence of heat-killed S. gordonii. Heat-killed S. gordonii increased the expression of c-Fos and NFATc1, which are essential transcription factors for osteoclast differentiation. On the other hand, heat-killed S. gordonii inhibited osteoblast differentiation and reduced the expression of Runx2, an essential transcription factor for osteoblast differentiation. S. gordonii exerts bone resorptive activity by increasing osteoclast differentiation and reducing osteoblast differentiation, which may be involved in periapical bone resorption.

In this study, we investigated the feasibility of enzymatic digestion of polysaccharides for cell sheet harvesting. Cellulose was digested using cellulase; in brief, cellulose was pre-coated under a confluent cell layer, and then enzymatic digestion of cellulose under the confluent cell layer enabled cell detachment with minimal cell damage, yielding cell sheets. For the surface adhesion of the cellulose, carboxymethyl cellulose (CMC) molecules were conjugated with dopamine (DA), and the synthesized CMC-DA was pre-treated onto the surface of the culture plates. Then, human mesenchymal stem cells (hMSCs) or corneal limbal epithelial cells (hCLEs) were cultured on the pre-coated CMC-DA and harvested using cellulase containing cell culture medium. Single hMSCs treated with cellulase showed higher proliferative activity, showing an aggregated morphology compared with trypsin-treated hMSCs. Additionally, hMSC sheets were detached from the pre-coated CMC-DA surface 10 min after cellulase treatment. Also, hCLE sheets were generated with a well-preserved morphology and transparency after cellulase-assisted cell sheet generation. These results demonstrate that the strategy of CMC-DA coating combined with cellulase enzymatic harvesting is an effective option for harvesting cell sheets.

We report the chemical solution deposition (CSD) of a phase-pure Bi2Fe4O9 thin film for use as a photoanode in photoelectrochemical (PEC) water splitting. The energy levels of Bi2Fe4O9 films have been measured and n-type characteristics have been confirmed. With band gaps determined as 2.05 eV (indirect) and 2.80 eV (direct) and valence and conduction bands straddling the water oxidation and reduction potentials, this material is highly promising as a photocatalyst for solar water splitting. The photocurrent of a planar photoanode reached 0.1 mA cm−2 at 1.23 VNHE under AM1.5G illumination. The addition of H2O2 as a hole scavenger increased the photocurrent to 0.25 mA cm−2, indicating hole injection is one limiting factor to the performance. The performance was enhanced by nearly 5-fold when the Bi2Fe4O9 photoanode is coupled to a Co–Pi surface co-catalyst. The photoanode also shows excellent stability with no change in photocurrent over three hours of continuous illumination. These results indicate that this material represents a promising addition to the growing selection of low-cost, stable photocatalysts for use in solar water splitting.