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Inoculation of Chinese cabbage leaves with high titer (107 cfu/ml) of the non-adapted bacteria Xanthomonas campestris pv. vesicatoria (Xcv) strain Bv5-4a.1 triggered rapid leaf tissue collapses and hypersensitive cell death (HCD) at 24 h. Electrolyte leakage and lipid peroxidation markedly increased in the Xcv-inoculated leaves. Defence-related gene expressions (BrPR1, BrPR4, BrChi1, BrGST1 and BrAPX1) were preferentially activated in the Xcv-inoculated leaves. The Xcv-triggered HCD was attenuated by continuous light but accelerated by a dark environment, and the prolonged high relative humidity also alleviated the HCD. Constant dark and increased relative humidity provided favorable conditions for the Xcv bacterial growth in the leaves. Pretreated fluridone (biosynthetic inhibitor of endogenous abscisic acid [ABA]) increased the HCD in the Xcv-inoculated leaves, but exogenous ABA attenuated the HCD. The pretreated ABA also reduced the Xcv bacterial growth in the leaves. These results highlight that the onset of HCD in Chinese cabbage leaves initiated by non-adapted pathogen Xcv Bv5-4a.1 and in planta bacterial growth was differently modulated by internal and external conditional changes.

Abstract Atomic sawtooth surfaces have emerged as a versatile platform for growth of single-crystal van der Waals layered materials. However, the mechanism governing the formation of single-crystal atomic sawtooth metal (copper or gold) films on hard substrates (tungsten or molybdenum) remains a puzzle. In this study, we aim to elucidate the formation mechanism of atomic sawtooth metal films during melting–solidification process. Utilizing molecular dynamics, we unveil that the solidification of the liquid copper initiates at a high-index tungsten facet with higher interfacial energy. Subsequent tungsten facets follow energetically favourable pathways of forming single-crystal atomic sawtooth copper film during the solidification process near melting temperature. Formation of atomic sawtooth copper film is guaranteed with a film thickness exceeding the grain size of polycrystalline tungsten substrate. We further demonstrate the successful growth of centimeter-scale single-crystal monolayer hexagonal boron nitride films on atomic sawtooth copper films and explore their potential as efficient oxygen barrier.

In July 2022, stem rot symptom was found in a peony plant grown in a pot under a greenhouse at Jinju, Gyeongnam Province, South Korea. Two fungal species were isolated from the infected peony stems and cultured on 1/2-strength potato dextrose agar for identification. The morphological characteristics of the fungal isolates were examined, and nucleotide sequences of the internal transcribed spacer region, β-tubulin and translation elongation factor 1-α were analysed. The pathogenicity of the two isolates was confirmed in detached peony leaves, according to Koch's postulates. To our knowledge, this is the report of Neopestalotiopsis clavispora and Sclerotinia sclerotiorum as the causal agents of peony stem rots. Antifungal activity of chemical fungicide propineb and rhizobacterium Bacillus siamensis H30-3 was shown against the two plant pathogenic fungi N. clavispora and S. sclerotiorum. Unidentified diffusible and volatile compounds from B. siamensis H30-3 could suppress in vitro mycelial growths of N. clavispora JJ 8-2-1 and S. sclerotiorum JJ 8-2-2.

Alternaria black spots or blights in cruciferous crops have been devastating diseases worldwide and led to economic losses in broccoli, Chinese cabbage, kale, radish, rapeseed, etc. These diseases are caused by different Alternaria spp., including A. brassicae, A. brassicicola and A. raphani transmitted from infected seeds or insect vectors. Efforts to excavate disease resistance traits of cruciferous crops against Alternaria black spots or blights have been demonstrated. Genetic resource of disease resistance was investigated in the wild relatives of cruciferous crops, and different cultivars were screened under different inoculation conditions. Development of the disease-resistant lines against Alternaria black spots or blights was also tried via genetic transformation of the cruciferous crops using diverse plant defence-associated genes. Plant immunity activated by pre-treatment with chemicals, i. e. β-amino-n-butyric acid and melatonin, was suggested for reducing Alternaria black spots or blights in cruciferous crops. The disease resistance traits have also been evaluated in model plant Arabidopsis originating from different habitats. Various plant immunity-related mutants showing different disease responses from wild-type Arabidopsis provided valuable information for managing Alternaria black spots or blights in cruciferous crops. In particular, redox regulation and antioxidant responses altered in the Alternaria-infected mutants were discussed in this review.

Abstract We report the emergence of dark-excitons in transition-metal-dichalcogenide (TMD) heterostructures that strongly rely on the stacking sequence, i.e., momentum-dark K-Q exciton located exclusively at the top layer of the heterostructure. The feature stems from band renormalization and is distinct from those of typical neutral excitons or trions, regardless of materials, substrates, and even homogeneous bilayers, which is further confirmed by scanning tunneling spectroscopy. To understand the unusual stacking sequence, we introduce the excitonic Elliot formula by imposing strain exclusively on the top layer that could be a consequence of the stacking process. We further find that the intensity ratio of Q- to K-excitons in the same layer is inversely proportional to laser power, unlike for conventional K-K excitons. This can be a metric for engineering the intensity of dark K-Q excitons in TMD heterostructures, which could be useful for optical power switches in solar panels.

Abstract Charge Density Waves (CDW) are commonly associated with the presence of near-Fermi level states which are separated from others, or “nested", by a wavector of q. Here we use Angle-Resolved Photo Emission Spectroscopy (ARPES) on the CDW material Ta2NiSe7 and identify a total absence of any plausible nesting of states at the primary CDW wavevector q. Nevertheless we observe spectral intensity on replicas of the hole-like valence bands, shifted by a wavevector of q, which appears with the CDW transition. In contrast, we find that there is a possible nesting at 2q, and associate the characters of these bands with the reported atomic modulations at 2q. Our comprehensive electronic structure perspective shows that the CDW-like transition of Ta2NiSe7 is unique, with the primary wavevector q being unrelated to any low-energy states, but suggests that the reported modulation at 2q, which would plausibly connect low-energy states, might be more important for the overall energetics of the problem.

Abstract Multi-terminal memristor and memtransistor (MT-MEMs) has successfully performed complex functions of heterosynaptic plasticity in synapse. However, theses MT-MEMs lack the ability to emulate membrane potential of neuron in multiple neuronal connections. Here, we demonstrate multi-neuron connection using a multi-terminal floating-gate memristor (MT-FGMEM). The variable Fermi level (E F) in graphene allows charging and discharging of MT-FGMEM using horizontally distant multiple electrodes. Our MT-FGMEM demonstrates high on/off ratio over 105 at 1000 s retention about ~10,000 times higher than other MT-MEMs. The linear behavior between current (I D) and floating gate potential (V FG) in triode region of MT-FGMEM allows for accurate spike integration at the neuron membrane. The MT-FGMEM fully mimics the temporal and spatial summation of multi-neuron connections based on leaky-integrate-and-fire (LIF) functionality. Our artificial neuron (150 pJ) significantly reduces the energy consumption by 100,000 times compared to conventional neurons based on silicon integrated circuits (11.7 μJ). By integrating neurons and synapses using MT-FGMEMs, a spiking neurosynaptic training and classification of directional lines functioned in visual area one (V1) is successfully emulated based on neuron’s LIF and synapse’s spike-timing-dependent plasticity (STDP) functions. Simulation of unsupervised learning based on our artificial neuron and synapse achieves a learning accuracy of 83.08% on the unlabeled MNIST handwritten dataset.

Chemical vapor deposition (CVD) can produce wafer-scale transition-metal dichalcogenide (TMD) monolayers for the integration of electronic and optoelectronic devices. Nonetheless, the material quality of the CVD-grown TMDs still remains controversial. Here, we compare the quality of representative WSe2 monolayers grown by CVD compared to that obtained by other synthesis methods: bulk-grown-chemical vapor transport (CVT) and flux. Through the use of a deep-learning–based algorithm to analyze atomic-resolution scanning transmission electron microscopy images, we confirm that Se vacancies (VSe) are the primary defects in WSe2, with a defect density of ∼5.3 × 1013 cm−2 in the CVD-grown sample, within the same order of magnitude of other methods (∼3.9 × 1013 cm−2 from CVT-grown samples and ∼2.7 × 1013 cm−2 from flux-grown samples). The carrier concentration in field-effect transistors at room temperature is ∼5.84 × 1012 cm−2 from a CVD-grown sample, comparable to other methods (6–7 × 1012 cm−2). The field-effect mobility of the CVD-grown sample is slightly lower than that of other synthesis methods, together with similar trends in on-current. While the difference in photoluminescence intensity is not appreciable at room temperature, different intensities of defect-related localized states appear below 60 K. We conclude that the wafer-scale CVD-grown samples can be utilized without loss of generality in the integration of electronic/optoelectronic devices.

Eating behviours consist of seeking and consummatory phases. Here, authors show that two distinct lateral hypothalamic leptin receptor neurons orchestrate seeking and consummatory phases of eating behaviour via hunger signal, Neuropeptide Y.

Constructing atomically flat surface in a single crystal ultrathin film is difficult owing to the coherent merging of trillions of clusters. Here the authors establish the initial growth mechanism of a single crystal Cu thin film with atomically flat surface using atomic sputtering epitaxy.

Nitric oxide (NO) is a self-regulating gaseous molecule as well as an interacting partner with different reactive oxygen species (ROS). Endogenous NO increased, but hydrogen peroxide (H2O2) and superoxide radical anion (${\rm O}_2^{\cdot -}$) decreased in Chinese cabbage leaves treated with sodium nitroprusside (SNP) (0.5 mM). Antioxidant enzyme genes BrCat1, BrCat2, BrAPX, BrGR1, and BrGST1 expressions were transiently induced by the SNP (0.5 mM). Pretreated SNP (0.5 mM) enhanced tolerance to subsequent challenges by phytotoxic SNP (5 mM) and methyl viologen (MV) (50 μM), but accelerated cellular damage by H2O2 (4 M) shown by electrolyte leakage and lipid peroxidation. The SNP (0.5 mM) differentially modulated endogenous NO and ROS levels as well as antioxidant enzyme gene expressions by excess SNP, MV, and H2O2 stresses. These results suggest that NO as a signal molecule differentially interacts with challenging stresses in Chinese cabbage leaves, followed by differential cellular damage and antioxidant responses.

Background: The PyeongChang 2018 Winter Paralympic Games (WPG) being one of the most successful Paralympic Games (PG) in modern athletic world history, hosted the largest number of elite athletes representing 49 National Paralympic Committees (NPCs). Objects: The present investigation highlighted the demographic and clinical characteristics of injured athletes and non-athletes and the physiotherapy services provided during the Py-eongChang 2018 WPG.Methods: Prospective descriptive epidemiology study, in which the study group comprised of 201 participants (51 athletes and 150 non-athletes) who were admitted to and utilized the polyclinic physiotherapy service of 2018 PyeongChang WPG in Physiotherapy Department of Paralympic Village from March 1, 2018 to March 20, 2018.Results: Qualitative frequency analysis of injury type demonstrated highest number of chron-ic injuries (51%, n = 100) in athletes and non-athletes. Anatomical injury site analysis revealed that the spine and shoulder areas were affected with equal frequency for athletes (54.9%, n = 14), whereas for non-athletes, the frequencies of spine and shoulder area injuries were 36.7% (n = 55) and 26% (n = 39), respectively. The Pyeongchang WPG showed a high rate of athletes visiting the physiotherapy service during the pre-competition period (33.3%, n = 50), which may have led to smaller incidence rate of traumatic injury. The physiotherapy treatment service analysis demonstrated that manual therapy (35.4%, n = 230) was most commonly utilized, followed by transcutaneous electrical nerve stimulation/interference current therapy (TENS/ICT), therapeutic massage and therapeutic exercise.Conclusion: We established the importance of prophylactic and preventive physiotherapy services to reduce the risk of sports injuries during WPG.

Microscopic origins of thermopower are investigated to design efficient thermoelectric devices. Here, the authors report thermopower and phonon puddles in the charge density wave states in 1T-TaS2 by scanning thermoelectric microscopy.

The van der Waals integration of molecular layer (0D) with 2D or 3D electrodes is limited at microscale junction. Here, the authors introduce 1D-0D-1D vdWI memory with 1 nm2 junction achieved by cross-stacking t-CNT on molecularly assembled b-CNT.

Abstract Excitonic insulators exhibit intriguing quantum phases that further attract numerous interests in engineering the electrical and optical properties of Ta2NiSe5. However, tuning the electronic properties such as spin‐orbit coupling strength and orbital repulsion via pressure in Ta2NiSe5 are always accompanied with electron‐hole pair breaking, which is a bottleneck for further applications. Here, the robust excitonic‐insulating states invariant with electron‐doping concentrations in Ta2NiSe5 are demonstrated. The electron doping is conducted by substituting Cu into Ni site (Ta2Ni1‐xCuxSe5). The majority carrier of pristine sample is a hole‐type and is converted to electron‐type with a doping concentration over x = 0.01, whose carrier density can be controlled by varying the Cu concentration. The excitonic transition temperature (Tc) does not significantly alter with electron‐doping concentrations, which is stark contrast with the declining Tc as the hole‐type dopant of Fe or Co increases. The optical conductivity data also demonstrate the invariant excitonic‐insulating states in Cu‐doped Ta2NiSe5. The findings of invariant excitonic‐insulating states in n‐type Cu‐substituted Ta2NiSe5 can be utilized for further electronic device applications by using excitons.

Abstract Two-dimensional (2D) molybdenum disulfide (MoS2) has been recognized as a potential substitution of platinum (Pt) for electrochemical hydrogen evolution reaction (HER). However, the broad adoption of MoS2 is hindered by its limited number of active sites and low inherent electrical conductivity. In this work, we employed a one-step solvothermal synthesis technique to construct a ternary hybrid structure consisting of dual-phase MoS2, titanium carbide (Ti3C2) MXene, and carbon nanotubes (CNTs), and demonstrated synergistic effects for active site exposure, surface area enlargement, and electrical conductivity improvement of the catalyst. The dual-phase MoS2 (DP-MoS2) is directly formed on the MXene with CNTs acting as crosslinks between 2D islands. The existence of edge-enriched metallic phase MoS2, the conductive backbone of MXene along with the crosslink function of CNTs clearly improves the overall HER performance of the ternary nanocomposite. Moreover, the integration of MoS2 with MXene not only increases the interlayer distance of the 2D layers but also partially suppresses the MXene oxidation and the 2D layer restacking, leading to good catalytic stability. As a result, an overpotential of 169 mV and a low Tafel slope of 51 mV/dec was successfully achieved. This work paves a way for 2D-based electrocatalyst engineering and sheds light on the development of the next-generation noble metal-free HER electrocatalysts.

Abstract Although large exciton binding energies of typically 0.6–1.0 eV are observed for monolayer transition metal dichalcogenides (TMDs) owing to strong Coulomb interaction, multilayered TMDs yield relatively low exciton binding energies owing to increased dielectric screening. Recently, the ideal carrier-multiplication threshold energy of twice the bandgap has been realized in multilayered semiconducting 2H-MoTe2 with a conversion efficiency of 99%, which suggests strong Coulomb interaction. However, the origin of strong Coulomb interaction in multilayered 2H-MoTe2, including the exciton binding energy, has not been elucidated to date. In this study, unusually large exciton binding energy is observed through optical spectroscopy conducted on CVD-grown 2H-MoTe2. To extract exciton binding energy, the optical conductivity is fitted using the Lorentz model to describe the exciton peaks and the Tauc–Lorentz model to describe the indirect and direct bandgaps. The exciton binding energy of 4 nm thick multilayered 2H-MoTe2 is approximately 300 meV, which is unusually large by one order of magnitude when compared with other multilayered TMD semiconductors such as 2H-MoS2 or 2H-MoSe2. This finding is interpreted in terms of small exciton radius based on the 2D Rydberg model. The exciton radius of multilayered 2H-MoTe2 resembles that of monolayer 2H-MoTe2, whereas those of multilayered 2H-MoS2 and 2H-MoSe2 are large when compared with monolayer 2H-MoS2 and 2H-MoSe2. From the large exciton binding energy in multilayered 2H-MoTe2, it is expected to realize the future applications such as room-temperature and high-temperature polariton lasing.

The industrial application of two-dimensional (2D) materials strongly depends on the large-scale manufacturing of high-quality 2D films and powders. Here, the authors analyze three state-of-the art mass production techniques, discussing the recent progress and remaining challenges for future improvements.

A positive correlation has been demonstrated between gross domestic product (GDP) per capita and COVID-19 tests per 1000 people. Although frequently used as an indicator of economic performance, GDP per capita does not directly reflect income distribution inequalities and imposed health costs. In this longitudinal ecological study, we aimed to determine if, besides GDP per capita, indicators relating to governance, public health measures enforcement, and health and research investment explain differences in RT-PCR testing rates among countries in Southeast Asia (SEA) during the first six months of the COVID-19 pandemic. Using open-access COVID-19 panel data, we estimated the effect of various indicators (GDP per capita, health expenditure per capita, number of researchers per one million population, corruption perceptions index, stringency index, regional authority index) on daily COVID-19 testing by performing fixed-effects negative binomial regression. After accounting for all indicators, the number of daily confirmed COVID-19 cases, and population density, the model provided a 2019 GDP per capita coefficient of 0.0046330 (95% CI: 0.0040171, 0.0052488; p

Abstract Monolayers of transition metal dichalcogenides are semiconducting materials which offer many prospects in optoelectronics. A monolayer of molybdenum disulfide (MoS2) has a direct bandgap of 1.88 eV. Hence, when excited with optical photon energies below its bandgap, no photocarriers are generated and a monolayer of MoS2 is not of much use in either photovoltaics or photodetection. Here, we demonstrate that large size MoS2 monolayer sandwiched between two graphene layers makes this heterostructure optically active well below the band gap of MoS2. An ultrafast optical pump‐THz probe experiment reveals in real‐time, transfer of carriers between graphene and MoS2 monolayer upon photoexcitation with photon energies down to 0.5 eV. It also helps to unravel an unprecedented enhancement in the broadband transient THz response of this tri‐layer material system. We propose possible mechanism which can account for this phenomenon. Such specially designed heterostructures, which can be easily built around different transition metal dichalcogenide monolayers, will considerably broaden the scope for modern optoelectronic applications at THz bandwidth.

Abstract Proximity effect, which is the coupling between distinct order parameters across interfaces of heterostructures, has attracted immense interest owing to the customizable multifunctionalities of diverse 3D materials. This facilitates various physical phenomena, such as spin order, charge transfer, spin torque, spin density wave, spin current, skyrmions, and Majorana fermions. These exotic physics play important roles for future spintronic applications. Nevertheless, several fundamental challenges remain for effective applications: unavoidable disorder and lattice mismatch limits in the growth process, short characteristic length of proximity, magnetic fluctuation in ultrathin films, and relatively weak spin–orbit coupling (SOC). Meanwhile, the extensive library of atomically thin, 2D van der Waals (vdW) layered materials, with unique characteristics such as strong SOC, magnetic anisotropy, and ultraclean surfaces, offers many opportunities to tailor versatile and more effective functionalities through proximity effects. Here, this paper focuses on magnetic proximity, i.e., proximitized magnetism and reviews the engineering of magnetism‐related functionalities in 2D vdW layered heterostructures for next‐generation electronic and spintronic devices. The essential factors of magnetism and interfacial engineering induced by magnetic layers are studied. The current limitations and future challenges associated with magnetic proximity‐related physics phenomena in 2D heterostructures are further discussed.

Acoustic graphene plasmons are superior to the graphene surface plasmons in field confinement and normalized propagation length, thus promising for applications. Here, the authors report near-field imaging of acoustic plasmons in high-quality CVD graphene, measure the AGP dispersion and propagation loss, and investigate their behavior in a periodic structure.

Objective To determine the immediate and short-term impact of the application of wearable balance compensation system (BCS) on balance impairment in patients with spinocerebellar ataxia (SCA). Methods The study enrolled 6 participants with SCA with varying degrees of balance impairment. After adjustment for individual fitting, wearable BCS with up to 3% body weight was placed in a garment on the trunk. Sway direction and magnitude were measured with sensors placed posteriorly at the lumbosacral junction, immediately before and after, and at day 1, day 2, and day 7 after wearing the BCS. Timed Up & Go test (TUG) and 25-foot timed walk test were performed, and static foot pressure was measured. Results A significant improvement in static and dynamic balance was found during the 25-foot timed walk and in static foot pressure measurement results after wearing the BCS, when compared with that at baseline (p=0.044 vs. p=0.011). Anterior and posterior sway showed improvements from baseline after wearing the BCS. Improvement in the lateral swaying movement control was also seen. Conclusion Application of the BCS might be beneficial in the improvement ofthe static and dynamic balance in patients with SCA. Further research on long-term effects and with a larger sample size is indicated.

Ferromagnetic quasi-atomic behavior of interstitial anionic electrons (IAEs) in practical electrides is yet to be discovered experimentally. Here, the authors reveal that IAEs in two-dimensional electride [Gd2C]²+⋅2e- behave as magnetic elements with their own magnetic moment.

Abstract The confined defects in 2D van der Waals (vdW)‐layered semiconductors can be easily tailored using charge doping, strain, or an electric field. Nevertheless, gate‐tunable magnetic order via intrinsic defects has been rarely observed to date. Herein, a gate‐tunable magnetic order via resonant Se vacancies in WSe2 is demonstrated. The Se‐vacancy states are probed via photocurrent measurements with gating to convert unoccupied states to partially occupied states associated with photo‐excited carrier recombination. The magneto‐photoresistance hysteresis is modulated by gating, which is consistent with the density functional calculations. The two energy levels associated with Se vacancies split with increasing laser power, owing to the robust Coulomb interaction and strong spin–orbit coupling. The findings offer a new approach for controlling the magnetic properties of defects in optoelectronic and spintronic devices using vdW‐layered semiconductors.

Abstract Atomic dopants and defects play a crucial role in creating new functionalities in 2D transition metal dichalcogenides (2D TMDs). Therefore, atomic‐scale identification and their quantification warrant precise engineering that widens their application to many fields, ranging from development of optoelectronic devices to magnetic semiconductors. Scanning transmission electron microscopy with a sub‐Å probe has provided a facile way to observe local dopants and defects in 2D TMDs. However, manual data analytics of experimental images is a time‐consuming task, and often requires subjective decisions to interpret observed signals. Therefore, an approach is required to automate the detection and classification of dopants and defects. In this study, based on a deep learning algorithm, fully convolutional neural network that shows a superior ability of image segmentation, an efficient and automated method for reliable quantification of dopants and defects in TMDs is proposed with single‐atom precision. The approach demonstrates that atomic dopants and defects are precisely mapped with a detection limit of ≈1 × 1012 cm−2, and with a measurement accuracy of ≈98% for most atomic sites. Furthermore, this methodology is applicable to large volume of image data to extract atomic site‐specific information, thus providing insights into the formation mechanisms of various defects under stimuli.

Abstract Among transition metal dichalcogenides (TMdCs) as alternatives for Pt‐based catalysts, metallic‐TMdCs catalysts have highly reactive basal‐plane but are unstable. Meanwhile, chemically stable semiconducting‐TMdCs show limiting catalytic activity due to their inactive basal‐plane. Here, metallic vanadium sulfide (VSn) nanodispersed in a semiconducting MoS2 film (V–MoS2) is proposed as an efficient catalyst. During synthesis, vanadium atoms are substituted into hexagonal monolayer MoS2 to form randomly distributed VSn units. The V–MoS2 film on a Cu electrode exhibits Pt‐scalable catalytic performance; current density of 1000 mA cm−2 at 0.6 V and overpotential of −0.08 V at a current density of 10 mA cm−2 with excellent cycle stability for hydrogen‐evolution‐reaction (HER). The high intrinsic HER performance of V–MoS2 is explained by the efficient electron transfer from the Cu electrode to chalcogen vacancies near vanadium sites with optimal Gibbs free energy (−0.02 eV). This study provides insight into ways to engineer TMdCs at the atomic‐level to boost intrinsic catalytic activity for hydrogen evolution.

During carrier multiplication, high-energy free carriers in a given material relax by generation of additional electron-hole pairs. Here, the authors report evidence of carrier multiplication in multilayer MoTe2 and WSe2 films with up to 99% conversation efficiency.

Gallarhois (GR) is a traditional oriental herbal medicine with various pharmacological effects; however, its effect on gastric ulcer has not been previously explored. We firstly investigated the component and antioxidant activity of GR extract (EtGR) by HPLC analysis and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The results showed that EtGR consisted of gallotannin (68.7%), gallic acid (27.2%) and methyl gallate (4.1%) and that it had a high antioxidant value (IC50 value; 1.93 μg/mL). To evaluate the possible anti-gastric ulcer potential of EtGR, we investigated the effects of EtGR in the model of ethanol/hydrochloric acid (EtOH/HCl)-induced gastric ulcer. Gross and histological gastric lesions, biochemical and gene expression parameters were taken into consideration. The results showed that EtOH/HCl treatment produced mucosal injuries with morphological and histological damage, whereas EtGR co-treatment reduced the gastric injuries. EtGR treatment also decreased the contents of malonaldehyde (MDA) activity relative to the vehicle group. Moreover, EtGR decreased the levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and cyclo-oxygenase-2 (COX-2) expression. Finally, EtGR did not induce any specific toxicity in the livers or kidneys of the EtOH/HCl-induced gastric ulcer model. These results suggest that EtGR had stronger antioxidant activity and could be a new useful natural drug for gastroprotection against gastric ulcer. Moreover, these findings provide a scientific basis for the development of drugs from traditional oriental herbal medicines. Keywords: Gallarhois, Anti-gastric ulcer, Antioxidant, Toxicity, Animal model

What drives us to eat? It is one of the most fundamental questions in the obesity research field which have been investigated for centuries. Numerous novel in vivo technologies in the neuroscience field allows us to reevaluate the multiple components and phases of food-related behaviors. Focused on the cognitive, executive, behavioral and temporal aspects, food-related behaviors can be distinguished into appetitive phase (food craving→food seeking) and consummatory phase (food consumption). Food craving phase is an internal state or stage in which the animal has the motivation to eat the food but there is no actual food specific behaviors or actions. Food seeking phase entails repeated behaviors with a food searching purpose until the animal discovers the food (or food-related cue) and the approach behavior stage after the discovery of food. Food consumption phase is the step that the animal grabs, chews and intake the food. This review will specifically focus on characteristics and evaluation methods for each phase of food-related behavior in rodent, non-human primates and human.

Objective To elucidate the effect of task-specific lower extremity training (TSLET) on cognitive and gait function in stroke patients. Methods Thirty-eight patients were assigned to either the TSLET group or the control group. The individuals of TSLET group went through a TSLET plus conventional physical therapy. The control group received two sessions of conventional physical therapy. The primary outcome involved the assessment with visual and auditory digit span test. The secondary outcome was evaluated by the Korean version of Mini-Mental State Examination (K-MMSE) and Global Deterioration Scale (GDS) for cognitive function, Berg Balance Scale (BBS), Time Up and Go Test (TUG), 10 meters Walking Test (10mWT), 6 minutes Walking Test (6MWT), and Korean version of Modified Barthel Index (K-MBI) for gait, balance, and functional ability. Results After intervention (3 weeks) and 2 weeks of follow-up, the TSLET group showed statistically significant improvement in the visual digit span test backwards compared with the control group. In secondary outcome, a significant improvement was observed in GDS, BBS, TUG, and 10mWT in the TSLET group. There was no significant difference between the two groups concerning visual digit span test forward, auditory forward and backward digit span tests, K-MMSE, 6MWT, and K-MBI. Conclusion TSLET could be a useful alternative strategy for improving cognitive and gait function in stroke patients.

We report the strong ferromagnetic order in van der Waals (vdW) layered SnS2 induced by cobalt substitution. The single-crystal Co-doped SnS2 grown by a self-flux method reveals a relatively high Curie temperature (TC) of ∼131 K with an in-plane magnetic easy axis and a large saturation magnetization of ∼0.65 emu g−1 for the 2 at. % Co concentration, which is two orders of magnitude larger than the previously reported value for transition-metal-doped SnS2. The average magnetic moment per Co atom, as high as 1.08 µB, is consistent with the calculated value based on density functional theory, i.e., 1 µB, indicating a negligible antiferromagnetic coupling between Co atoms. Magnetoresistance shows a change in sign from positive to negative, which further confirms the ferromagnetic order in Co-doped SnS2. Our s-p hybridized vdW layered SnS2 serves as a host semiconductor material to search for a suitable magnetic dopant with a high magnetic moment and room temperature TC for next-generation spintronics.

We construct high-quality graphene-based van der Waals devices with narrow superconducting niobium nitride (NbN) electrodes, in which superconductivity and a robust fractional quantum Hall (FQH) state coexist. We find a possible signature for crossed Andreev reflection (CAR) across the superconductor separating two FQH edges. Our observed CAR probabilities in the particlelike fractional fillings are markedly higher than those in the integer and hole-conjugate fractional fillings and depend strongly on temperature and magnetic field unlike the other fillings. Further, we find a filling-independent CAR probability in integer fillings, which we attribute to spin-orbit coupling in NbN allowing for Andreev reflection between spin-polarized edges. These results provide a route to realize novel topological superconducting phases in FQH-superconductor hybrid devices based on graphene and NbN.

Abstract Many‐body effect and strong Coulomb interaction in monolayer transition metal dichalcogenides lead to intrinsic bandgap shrinking, originating from the renormalization of electrical/optical bandgap, exciton binding energy, and spin‐orbit splitting. This renormalization phenomenon has been commonly observed at low temperature and requires high photon excitation density. Here, the augmented bandgap renormalization (BGR) in monolayer MoS2 anchored on CsPbBr3 perovskite quantum dots at room temperature via charge transfer is presented. The amount of electrons significantly transferred from perovskite gives rise to the large plasma screening in MoS2. The bandgap in heterostructure is red‐shifted by 84 meV with minimal pump fluence, the highest BGR in monolayer MoS2 at room temperature, which saturates with a further increase of pump fluence. Further, it is found that the magnitude of BGR inversely relates to Thomas–Fermi screening length. This provides plenty of room to explore the BGR within existing vast libraries of large bandgap van der Waals heterostructure toward practical devices such as solar cells, photodetectors, and light‐emitting‐diodes.

Glucagon-like peptide-1 (GLP-1), whose agonists are widely prescribed, is a peptide proven effective in reducing obesity. Similarly, oxytocin (OXT) is a peptide known to increase satiety and help reduce body weight. In the present study, we aimed to examine the metabolic effects of co-administration of GLP-1 and OXT in diet-induced obesity (DIO) mice to elucidate their functions and interactions in the central nervous system. To this end, 40 DIO mice were subjected to stereotaxic surgery for the installation of an osmotic minipump and intracerebroventricular administration of GLP-1, OXT, or both. Initially, it was anticipated that co-administration of these anorexigenic peptides would be as effective as, if not more than, either GLP-1 or OXT alone in providing metabolic benefits to the obese mice. Interestingly, co-administration of OXT and GLP-1 offset the reductions in body weight and food intake promoted by either peptide alone. Co-administration also negated the decrease in fat and increase in lean mass produced by either peptide alone. Moreover, co-administration showed an equivalent calorimetric benefit as either peptide alone. Therefore, these results suggest antagonistic, rather than synergistic or additive, effects of centrally administered GLP-1 and OXT that attenuate the metabolic benefits of either peptide.

Generation of spin-charge coupling by doping semiconductors with magnetic dopants is a promising approach for gate-tunable spintronic devices without applying an external magnetic field. Here, we demonstrate that the magnetic orders in V-doped WSe2 can be modulated by tuning carrier densities using ab initio calculations. We found that at a low V-doping concentration limit, the long-range ferromagnetic order is enhanced by increasing the hole density. In contrast, this long-range ferromagnetic order is suppressed at high electron density by compensating the p-type V dopant, originating from the strong localized antiferromagnetic coupling between V and W atoms and between V and Se atoms. The hole-mediated long-range magnetic exchange is ∼70 meV, thus strongly suggesting the ferromagnetism in V-doped WSe2 at room temperature. Our findings on strong coupling between charge and spin order in V-doped WSe2 provide plenty of room for multifunctional gate-tunable spintronics.

Abstract Diluted magnetic semiconductors including Mn‐doped GaAs are attractive for gate‐controlled spintronics but Curie transition at room temperature with long‐range ferromagnetic order is still debatable to date. Here, the room‐temperature ferromagnetic domains with long‐range order in semiconducting V‐doped WSe2 monolayer synthesized by chemical vapor deposition are reported. Ferromagnetic order is manifested using magnetic force microscopy up to 360 K, while retaining high on/off current ratio of ≈105 at 0.1% V‐doping concentration. The V‐substitution to W sites keeps a V–V separation distance of 5 nm without V–V aggregation, scrutinized by high‐resolution scanning transmission electron microscopy. More importantly, the ferromagnetic order is clearly modulated by applying a back‐gate bias. The findings open new opportunities for using 2D transition metal dichalcogenides for future spintronics.

Abstract Atomically thin 2D van der Waals semiconductors are promising candidates for next‐generation nanoscale field‐effect transistors (FETs). Although large‐area 2D van der Waals materials have been successfully synthesized, such nanometer‐length‐scale devices have not been well demonstrated in 2D van der Waals semiconductors. Here, controllable nanometer‐scale transistors with a channel length of ≈10 nm are fabricated via vertical channels by squeezing an ultrathin insulating spacer between the out‐of‐plane source and drain electrodes, and the feasibility of high‐density and large‐scale fabrication is demonstrated. A large on‐current density of ≈70 µA µm−1 nm−1 at a source–drain voltage of 0.5 V and a high on/off ratio of ≈107–109 are obtained in ultrashort 2D vertical channel FETs with monolayer MoS2 synthesized through chemical vapor deposition. The work provides a promising route toward the complementary metal–oxide–semiconductor‐compatible fabrication of wafer‐scale 2D van der Waals transistors with high‐density integration.

Abstract 2D van der Waals layered heterostructures allow for a variety of energy band offsets, which help in developing valuable multifunctional devices. However, p–n diodes, which are typical and versatile, are still limited by the material choice due to the fixed band structures. Here, the vanadium dopant concentration is modulated in monolayer WSe2 via chemical vapor deposition to demonstrate tunable multifunctional quantum tunneling diodes by vertically stacking SnSe2 layers at room temperature. This is implemented by substituting tungsten atoms with vanadium atoms in WSe2 to provoke the p‐type doping effect in order to efficiently modulate the Fermi level. The precise control of the vanadium doping concentration is the key to achieving the desired quantum tunneling diode behaviors by tuning the proper band alignment for charge transfer across the heterostructure. By constructing a p–n diode for p‐type V‐doped WSe2 and heavily degenerate n‐type SnSe2, the type‐II band alignment at low V‐doping concentration is clearly shown, which evolves into the type‐III broken‐gap alignment at heavy V‐doping concentration to reveal a variety of diode behaviors such as forward diode, backward diode, negative differential resistance, and ohmic resistance.

Abstract For the accurate measurement of temperature in the upper air by using radiosondes, one prerequisite is the compensation of solar radiation effects that cause sensor heating. The development at the Korea Research Institute of Standards and Science (KRISS) of an upper air simulator (UAS) that can simulate radiation effects is reported. The UAS can independently control four environmental parameters: irradiance, temperature, pressure and air speed. An entire radiosonde can be installed in the test chamber and the measurement data transmitted remotely via an antenna. Solar irradiance is mimicked by using a solar simulator that irradiates the radiosonde sensor. The temperature of the test chamber is controlled from −70 to 20°C by placing it inside a climatic chamber. The pressure and ventilation speed in the test chamber are modulated using combinations of sonic nozzles, a mass flow controller and a vacuum pump. A ventilation speed of 5 m·s−1, which mimics the speed of ascent of the radiosondes when lifted using a balloon, is achieved at pressures as low as 7 hPa. The capability of controlling the environmental parameters independently and the stability of each parameter are presented. As a proof of concept, the radiation‐induced bias on the temperature sensor of a commercial radiosonde Vaisala RS41 is measured. The effect of each parameter is investigated by varying it while keeping the other parameters fixed. Radiosonde calibration using the UAS at the KRISS will help improve the traceability of upper air measurements to the International System of Units.

Two rhizobacteria Bacillus aryabhattai H26-2 and B. siamensis H30-3 were evaluated whether they are involved in stress tolerance against drought and high temperature as well as fungal infections in Chinese cabbage plants. Chinese cabbage seedlings cv. Ryeokgwang (spring cultivar) has shown better growth compared to cv. Buram-3-ho (autumn cultivar) under high temperature conditions in a greenhouse, whilst there was no difference in drought stress tolerance of the two cultivars. In vitro growth of B. aryabhattai H26-2 and B. siamensis H30-3 were differentially regulated under PEG 6000-induced drought stress at different growing temperatures (30, 40 and 50°C). Pretreatment with B. aryabhattai H26-2 and B. siamensis H30-3 enhanced the tolerance of Chinese cabbage seedlings to high temperature, but not to drought stress. It turns out that only B. siamensis H30-3 showed in vitro antifungal activities and in planta crop protection against two fungal pathogens Alternaria brassicicola and Colletotrichum higginsianum causing black spots and anthracnose on Chinese cabbage plants cv. Ryeokgwang, respectively. B. siamensis H30-3 brings several genes involved in production of cyclic lipopeptides in its genome and secreted hydrolytic enzymes like chitinase, protease and cellulase. B. siamensis H30-3 was found to produce siderophore, a high affinity iron-chelating compound. Expressions of BrChi1 and BrGST1 genes were up-regulated in Chinese cabbage leaves by B. siamensis H30-3. These findings suggest that integration of B. aryabhattai H26-2 and B. siamensis H30-3 in Chinese cabbage production system may increase productivity through improved plant growth under high temperature and crop protection against fungal pathogens.

Alternaria leaf spot disease has been a concern during a tomato production in greenhouse. In vitro antifungal activities of vapours of four plant essential oils, cinnamon oil, fennel oil, origanum oil and thyme oil, were investigated during in vitro conidial germination and mycelial growth of Alternaria alternata causing the tomato leaf spots to find eco-friendly alternatives for chemical fungicides. The four plant essential oils showed different antifungal activities against in vitro conidial germination of A. alternata in dose-dependent manners, and cinnamon oil vapour was most effective to suppress the conidial germination. The four plant essential oils showed similar antifungal activities against the in vitro mycelial growth of A. alternata in dose-dependent manners, but low doses of thyme oil vapour slightly increased in vitro mycelial growth of A. alternata. Necrotic lesions on the A. alternata-inoculated tomato leaves were reduced differently depending on kinds and concentrations of plant essential oils. Delayed conidial germination and germ-tube elongation of A. alternata were found on the tomato leaves treated with cinnamon oil and origanum oil vapours at 6 hpi. These results suggest that volatiles from cinnamon oil and origanum oil can be provided as alternatives to manage Alternaria leaf spot during the tomato production eco-friendly.

The interplay between strong interactions and presence of disorder makes atomically thin transition metal dichalcogenides an ideal platform to study phase transitions and critical phenomena. Here, the authors observe asymmetric critical exponents around the metal-insulator-transition of multilayer MoS2.

Peroxyacetic acid mixture Perosan, composed of peroxyacetic acid, hydrogen peroxide and acetic acid, was evaluated for eco-friendly management of tomato bacterial wilt by Ralstonia pseudosolanacearum. Perosan drastically suppressed in vitro growth of R. pseudosolanacearum in liquid cultures in dose- and incubation time-dependent manners. Higher perosan doses (0.1 and 1%) caused lowered pH and phytotoxicity to detached leaves of two tomato cultivars Cupirang and Benekia 220 in aqueous solution. Treatment with 0.01% of Perosan delayed wilting symptom significantly in the detached leaves of two cultivars inoculated with R. pseudosolanacearum (10⁷ cfu/ml). Soil drenching of 5% Perosan solution in pots caused severe tissue collapse of tomato seedlings at the four-week-old stage of two tomato cultivars. Treatment with 1% Perosan by soil-drenching significantly reduced bacterial wilt in the tomato seedlings of two cultivars. These findings suggest that Perosan treatment can be applied to suppress bacterial wilt during tomato production.

Two dimensional monolayer transition metal ditellurides and their alloys are interesting but their growth has been difficult. Herein, Yun et al. demonstrate the use of sodium salts to convert transition metal disulfide to ditelluride and alloys in tellurium vapor at low temperature.

The intrinsic properties of atomically thin MoS2 are believed to be strongly affected by the presence of structural defects; however, the underlying physical mechanism of such link is not fully understood. Here, the authors combine noise-current analysis with atomic force microscopy to explore the relationship between point defects and the anomalous physical properties of MoS2 monolayers.

Abstract A highly efficient and simple chemoselective aerobic oxidation of primary alcohols to either aldehydes or carboxylic acids in the presence of nitric acid was developed, utilising 5 wt% graphene oxide as a carbocatalyst under ambient reaction conditions. Carboxylic acid functional groups on graphene oxides played a vital role in carbocatalyst activity, greatly influencing both the reactivity and selectivity. We also applied this protocol to a variant of the Knoevenagel condensation for primary alcohols and malonates with a secondary amine co-catalyst via cooperative catalysis.

Background Carbapenem-resistant Enterobacteriaceae (CRE) with acquired metallo β-lactamase (MBL) resistance have been increasingly reported worldwide and associated with significant mortality and morbidity. Here, an outbreak of genetically related strains of Klebsiella pneumoniae producing the imipenemase (IMP)-1 MBL in a medical intensive care unit (MICU) in Korea is reported. Methods Since isolating carbapenem-resistant K. pneumoniae (CRKP) at the MICU of the hospital on August 10, 2011, surveillance cultures for CRE in 31 hospitalized patients were performed from August to September 2011. Carbapenem resistance was determined based on the disk diffusion method outlined in the Clinical and Laboratory Standards Institute guidelines. Polymerase chain reaction (PCR) was performed for genes coding for β-lactamase. Associations among isolates were assessed via pulsed-field gel electrophoresis (PFGE). In addition, a surveillance study of environmental cultures and health-care workers (HCWs) was conducted in the MICU during the same time frame. Results During the study period, non-duplicated CRKP specimens were discovered in four patients in the MICU, suggestive of an outbreak. On August 10, 2011, CRKP was isolated from the sputum of a 79-year-old male patient who was admitted to the MICU. A surveillance study to detect additional CRE carriers by rectal swab revealed an additional three CRKP isolates. PCR and sequencing of the four isolates identified the presence of the IMP-1 gene. In addition, PFGE showed that the four isolated strains were genetically related. CRE was not identified in specimens taken from the hands of HCWs or other environmental sources during surveillance following the outbreak. Transmission of the carbapenemase-producing Enterobacteriaceae strain was controlled by isolation of the patients and strict contact precautions. Conclusions This study shows that rapid and systemic detection of CRE and strict infection controls are important steps in preventing nosocomial transmission.

How well the linear elastic fracture picture holds at small length scales and systems with reduced dimensionality remains an active area of inquiry. Here authors usein situ electron microscopy to study fracture in MoS2monolayers and report dislocation emission rates greater than expected accompanying crack propagation.