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In this study, we analyzed the environmental factors influencing the restoration process of the degraded ecosystem in the Inner Mongolian steppe, the largest steppe ecosystem in Asia, which is experiencing rapid desertification, and evaluated the effects of restoration on the damaged ecosystem in China. For this purpose, we selected degraded steppe areas left to desertification in the Hulunbuir region, four restored sites where vegetation was artificially introduced for restoration, and reference ecosystems, including a non-desertified area with the dominant Pinus sylvestris var. mongolica community and a meadow steppe area. We conducted analyses and monitoring of plant community characteristics and soil environmental factors to assess the progress of restoration. The results showed that the introduction of indigenous woody plants in the degraded areas led to a proportional increase in vegetation cover, plant biodiversity, and species abundance over time. The primary external forces driving the succession of vegetation in the restored sites were soil factors including organic matter content, temperature and total nitrogen levels, which were associated with an increase in vegetation cover. These results can be interpreted as an increase in vegetation cover leading to an increase in litter production. This in turn reduces soil temperature and evaporation, subsequently enhancing the activity of soil microorganisms. Over time, the species composition, structural diversity of communities, and ecosystem functions in the restored sites gradually became more similar to those of the reference ecosystems. This indicates that vegetation restoration in this area has been very successful. In particular, the positive change in local residents’ awareness regarding the necessity of restoration has been considered a crucial contribution to the success of restoration in the degraded areas. It has led to a decrease in perceived anthropogenic threats to the restored sites. These results indicate that the introduction of native woody plants is crucial and can increase vegetation cover and species composition complexity and local residents’ positive perception of restoration for the successful restoration of desertified drylands.

Abstract Recently, kagome lattice materials have emerged as a new model material platform for discovering and engineering novel quantum phases of matter. In this work, we elucidate the driving mechanism of the $$\sqrt{{{3}}}$$ 3 × $$\sqrt{{{3}}}$$ 3 charge order in a newly discovered kagome metal ScV6Sn6. Through multimodal investigations combining angle-resolved photoemission spectroscopy, phonon dispersion calculations, and phase diagram study, we identify the central role of unstable planar Sn and Sc phonon modes, while the electronic instability and van Hove singularities originating from the V kagome lattice have a marginal influence. Our results highlight that the $$\sqrt{{{3}}}$$ 3 × $$\sqrt{{{3}}}$$ 3 charge order in ScV6Sn6 is fundamentally distinguished from the electronically driven 2 × 2 charge order in the canonical kagome system AV3Sb5, uncovering a new mechanism to induce symmetry-breaking phase transition in kagome lattice materials.

Abstract We report a quantum criticality crossover representing two different universal scaling behaviors in a Kitaev quantum magnetic material α-RuCl3. α-RuCl3 presents both a symmetry-breaking antiferromagnetic order and a long-range entangled topological order of a quantum spin liquid, and thus could be a candidate system for a unique universality class involving deconfined fractionalized excitations of the local Z2 fluxes and itinerant Majorana fermions. Theoretical analyses on the inelastic neutron scattering, ac-magnetic susceptibility, and specific heat results demonstrate that Wilson–Fisher-Yukawa-type ‘conventional’ weak-coupling quantum criticality in high-energy scales crosses over to heavy-fermion-type ‘local’ strong-coupling one in low-energy scales. Our findings provide deep insight on how quantum criticality evolves in fermion-boson coupled topological systems with different types of deconfined fermions.

Abstract Quantum magnets admit more than one classical limit and N-level systems with strong single-ion anisotropy are expected to be described by a classical approximation based on SU(N) coherent states. Here we test this hypothesis by modeling finite temperature inelastic neutron scattering (INS) data of the effective spin-one antiferromagnet Ba2FeSi2O7. The measured dynamic structure factor is calculated with a generalized Landau-Lifshitz dynamics for SU(3) spins. Unlike the traditional classical limit based on SU(2) coherent states, the results obtained with classical SU(3) spins are in good agreement with the measured temperature dependent spectrum. The SU(3) approach developed here provides a general framework to understand the broad class of materials comprising weakly coupled antiferromagnetic dimers, trimers, or tetramers, and magnets with strong single-ion anisotropy.

Patients with recent pandemic coronavirus disease 19 (COVID-19) complain of neurological abnormalities in sensory functions such as smell and taste in the early stages of infection. Determining the cellular and molecular mechanism of sensory impairment is critical to understand the pathogenesis of clinical manifestations, as well as in setting therapeutic targets for sequelae and recurrence. The absence of studies utilizing proper models of human peripheral nerve hampers an understanding of COVID-19 pathogenesis. Here, we report that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directly infects human peripheral sensory neurons, leading to molecular pathogenesis for chemosensory impairments. An in vitro system utilizing human embryonic stem cell (hESC)-derived peripheral neurons was used to model the cellular and molecular pathologies responsible for symptoms that most COVID-19 patients experience early in infection or may develop as sequelae. Peripheral neurons differentiated from hESCs expressed viral entry factor ACE2, and were directly infected with SARS-CoV-2 via ACE2. Human peripheral neurons infected with SARS-CoV-2 exhibited impaired molecular features of chemosensory function associated with abnormalities in sensory neurons of the olfactory or gustatory organs. Our results provide new insights into the pathogenesis of chemosensory dysfunction in patients with COVID-19.

AbstractThis study was conducted to investigate the effect of changes in soil moisture content under climate change conditions on the growth response of Quercus dentata, a representative species of the genus Quercus on the Korean peninsula. The results showed that Q. dentata germination increased by 9.4 days under climate change conditions (RCP 4.5 scenario), whereas the below-ground biomass and plant biomass increased by 1.3 and 1.2 times, respectively. However, the soil moisture treatment condition solely affected the leaf area, below-ground biomass, and plant biomass but not the germination percentage, germination speed, above-ground length, and above-ground biomass. The variance across the measured growth variables was considerably higher in the control group than in the climate change treatment group, whereas the variance was lower for lower soil moisture content. The findings suggested that under climate change conditions, Q. dentata germinated rapidly and exhibited broader leaf area and increased development below ground, which may be advantageous for the early establishment of seedlings. However, the plants may face difficulties in conditions with low soil moisture content. In conclusion, with continuous climate changes, Q. dentata seedlings are predicted to efficiently adapt to the altered soil moisture content to exhibit even more reliable growth than with the current condition. However, the growth of Q. dentata seedlings would be more difficult with severely low soil moisture content than with abundant soil moisture content, which is predicted to be detrimental to population maintenance in the long term.

The electrical properties of (Ba0.7Sr0.3-xCax)(Ti0.9Zr0.1)O3 (0 ≤ x ≤ 0.2) (BSCTZ) ceramics prepared using citrate gelation (CG) method were investigated by substituting Ca2+ ions for the Sr2+ sites based on the structural characteristics of the ceramics. BSCTZ was sintered for 3 h at 1300 °C, lower than the temperature (1550 °C) at which the specimens prepared using the solid-state reaction (SSR) method were sintered, which lasted for 6 h. As the amount of substituted Ca2+ ions increased, the unit cell volume of the BSCTZ decreased because of the smaller ionic radius of the Ca2+ ions compared to the Sr2+ ions. The dielectric constant of BaTiO3-based ceramics is imparted by factors such as the tetragonality and B-site bond valence of the ceramics. Although the ceramic tetragonality increased with Ca2+ ion substitution, the x = 0.05 specimens exhibited the highest dielectric constant. The decrease in the dielectric constant of the sintered x > 0.05 specimens was attributed to the increase in the B-site bond valence of the ABO3 perovskite structure. Owing to the large number of grain boundaries, the breakdown voltage (6.6839 kV/mm) of the BSCTZ prepared using the CG method was significantly improved in relation to that (2.0043 kV/mm) of the specimen prepared using the SSR method.

To reveal the changes in the life history characteristics of grassland plants due to vegetation restoration, plant species and communities were analyzed for their competitor, stress tolerator, and ruderal (CSR) ecological strategies after the introduction of woody plants in the damaged steppe grassland and were compared with those in reference sites in Hulunbuir, Inner Mongolia. As a result, it was found that the introduction of the woody plants (Corethrodeneron fruticosum, Caragana microphylla, Populus canadensis, and Pinus sylvestris var. mongolica) into the damaged land greatly increased the plant species diversity and CSR eco-functional diversity as the succession progressed. The plant strategies of the temperate typical steppe (TTS) and woodland steppe (WS) in this Asian steppe are CSR and S/SR, respectively, which means that the plants are adapted to disturbances or stress. As the restoration time elapsed in the damaged lands exhibiting (R/CR) (Corispermum hyssopifolium), the ecological strategies were predicted to change in two ways: (1) →R/CSR (Cynanchum thesioides, Astragalus laxmannii, etc.) → CSR in places (TSS) (Galium verum var. asiaticum, Saussurea japonica, etc.) where only shrubs were introduced, and (2) → S/SR (Allium mongolicum, Ulmus pumila, etc.) → S/SR in sites (WS) (Ulmus pumila, Thalictrum squarrosum, etc.) where trees and shrubs were planted simultaneously. The results mean that the driving force that causes succession in the restoration of temperate grasslands is determined by the life-form (trees/shrubs) of the introduced woody plants. This means that for the restoration of these grasslands to be successful, it is necessary to introduce woody tree species at an early stage.

Anisotropic spin S >1/2 quantum magnets can have multiple low energy modes. In this manuscript, the authors study the interaction of such low energy modes in the S = 1 antiferromagnet Ba2FeSi2O7 by combining neutron scattering measurements with an SU(3) generalization of the 1/S expansion.

To identify effective light spectra for increasing the productivity of Panax ginseng, we conducted experiments in a controlled environment using a hydroponic cultivation system in a plant factory. We investigated the effect of single LEDs (red, blue, and yellow) and mixed LEDs (red + blue and red + blue + white). The relationships between four light spectra (red, blue, yellow, and white) and physiological responses (net photosynthetic rate, stomata conductance, transpiration rate, and intercellular CO2 partial pressure), as well as growth responses (shoot and root biomass), were analyzed using multivariate statistical analysis. Among the four physiological response variables, shoot biomass was not increased by any pathway, and root biomass was increased only by the intercellular CO2 partial pressure. Red and yellow light increased shoot biomass, whereas white light promoted an increase in the net photosynthetic rate and enhanced root biomass. In contrast, blue light was less effective than the other light spectra in increasing both shoot and root biomass. Therefore, red and yellow light are the most effective light spectra for increasing shoot biomass and white light is effective for increasing root biomass in a plant factory that uses artificial LED lighting. Furthermore, the intercellular CO2 partial pressure is an important physiological variable for increasing the root biomass of P. ginseng.

Abstract Orbital anisotropy at interfaces in magnetic heterostructures has been key to pioneering spin–orbit‐related phenomena. However, modulating the interface's electronic structure to make it abnormally asymmetric has been challenging because of lack of appropriate methods. Here, the authors report that low‐energy proton irradiation achieves a strong level of inversion asymmetry and unusual strain at interfaces in [Co/Pd] superlattices through nondestructive, selective removal of oxygen from Co3O4/Pd superlattices during irradiation. Structural investigations corroborate that progressive reduction of Co3O4 into Co establishes pseudomorphic growth with sharp interfaces and atypically large tensile stress. The normal component of orbital to spin magnetic moment at the interface is the largest among those observed in layered Co systems, which is associated with giant orbital anisotropy theoretically confirmed, and resulting very large interfacial magnetic anisotropy is observed. All results attribute not only to giant orbital anisotropy but to enhanced interfacial spin–orbit coupling owing to the pseudomorphic nature at the interface. They are strongly supported by the observation of reversal of polarity of temperature‐dependent Anomalous Hall signal, a signature of Berry phase. This work suggests that establishing both giant orbital anisotropy and strong spin–orbit coupling at the interface is key to exploring spintronic devices with new functionalities.

Lentiviruses have been widely used as a means of transferring exogenous DNAs into human cells to treat various genetic diseases. Lentiviral vectors are fundamentally integrated into the host genome, but their integration sites are generally unpredictable, which may increase the uncertainty for their use in therapeutics. To determine the viral integration sites in the host genome, several PCR-based methods have been developed. However, the sensitivities of the PCR-based methods are highly dependent on the primer sequences, and optimized primer design is required for individual target sites. In order to address this issue, we developed an alternative method for genome-wide mapping of viral insertion sites, named CReVIS-seq (CRISPR-enhanced Viral Integration Site Sequencing). The method is based on the sequential steps: fragmentation of genomic DNAs, in vitro circularization, cleavage of target sequence in a CRISPR guide RNA-specific manner, high-throughput sequencing of the linearized DNA fragments in an unbiased manner, and identification of viral insertion sites via sequence analysis. By design, CReVIS-seq is not affected by biases that could be introduced during the target enrichment step via PCR amplification using site specific primers. Furthermore, we found that multiplexed CReVIS-seq, using collections of different single-guide RNAs (sgRNAs), enables simultaneous identification of multiple target sites and structural variations (i.e., circularized viral genome), in both single cell clones and heterogeneous cell populations.

For the study on the relationships between the seed dispersal of exotic plants and bird population, flora, avifauna, vegetation patches, and the dynamics of seed banks were investigated in and around the exposed floodplains of the large rivers, and the causes of exotic vegetation development were determined with respect to plant life form, bird population characteristics, and landscape using multivariate analysis. The number of dominant exotic plant species observed in exposed areas was higher than that observed in an abandoned field and paddy field undergoing secondary succession. Additionally, the area occupied by exotic vegetation in exposed areas increased with the increase in number of vine plants and small terrestrial birds, whereas the relationship between vine and runner plants was inversely proportional. Therefore, to control exotic plants in exposed floodplains surrounding large rivers, it is necessary to remove vines and shrubs along the waterfront where small resident birds carrying plant seeds live and to maintain and manage runner plant populations. Furthermore, implementing an ecological landscape management strategy, such as afforestation through the planting of trees, may also be effective.

In this study, we examined the feasibility of Myzus persicae proliferation through interrelationships with host plants in a smart farm facility during winter. We investigated aphid proliferation under an LED artificial light source and attempted to interpret aphid proliferation in relation to the net photosynthetic rate of the host plant, Eutrema japonicum. We observed that aphids continuously proliferated in the smart farm facility in winter without dormancy. The average number of aphids was greater under the 1:1 red:blue light irradiation time ratio, where the photosynthetic rate of the host plant was lower than under the 5:1 and 10:1 red:blue light irradiation time ratios. These results show that it is important to maintain a low net photosynthetic rate of the host plant, E. japonicum, in order to effectively proliferate aphids under artificial light such as in the case of smart farm facilities.

Topological antiferromagnetic spintronics is an emerging field due to advantages such as no stray field effect and high-speed dynamics. In bismuth chalcogenide topological insulators, the coexistence of long-range antiferromagnetic order and topologically protected states has scarcely been observed. Here, an antiferromagnetic order, which sets in the direction of magnetic moments perpendicular to the c axis, is introduced by Eu substitution in Bi2Se3, and therefore it influences the topological electronic properties of Bi2Se3. Despite Eu substitution, Shubnikov–de Haas (SdH) oscillations are observed. The angle dependence of SdH oscillations shows a signature of anisotropic 3D Fermi surfaces with a nontrivial Berry phase by Eu substitution, and the temperature dependence of SdH oscillations reveals that the effective mass is comparable to the pristine Bi2Se3. These results suggest that the nontrivial topological state can survive in the antiferromagnetic order of Eu-substituted Bi2Se3. Our work expands the base of topological materials available for antiferromagnetic spintronics applications.

This research was conducted to examine the changes in growth and production of Oryza sativa L. cv. Ilmi, which was developed to cultivate high yielding rice variety in the Southern plains of Korea. The seedlings of the rice were cultivated from May to October in 2012 under three different conditions: control, AC-AT, ambient CO2 + ambient temperature; AC-ET, ambient CO2 + elevated temperature; EC-ET, elevated CO2 + elevated temperature. The aboveground biomass, belowground biomass, the total biomass of the rice, and panicle weight per individual were the heaviest in the EC-ET. But, the number of grains per panicle and the weight of one grain was higher at the condition of AC-ET and EC-ET than that of AC-AT. The number of tiller was higher at the condition of AC-AT and AC-ET than that of EC-ET. However, there was no significant difference in the number of panicles per individual and the ripened grain rate among the control and global warming treatments. Crop yield was the highest in the EC-ET. This result means that the global warming condition should be considered in the selection of suitable paddy field for the limibyeo in the future.

In complete denture fabrication, accurate preliminary impressions are crucial for obtaining an accurate final impression. However, it can be challenging in cases of atypical arch shapes. This case report compares diagnostic casts made with a stock tray and an intraoral scanner (IOS) in a patient with an atypical arch shape. A 58-year-old edentulous male patient with long, narrow, atypical arches was referred to the Oral and Maxillofacial Surgery department for complete denture fabrication. Compared to the diagnostic cast obtained using IOS with adequately captured anatomical parameters, the primary model obtained using a stock tray showed prominent overextended flanges on the labial and buccal sides of the maxillary arch and less prominent overextended flanges in the mandibular arch with pressure spots in the posterior palatal seal area. The custom tray fabricated from such a model required additional adjustment resulting in increased chair time during the final impression procedure. [ABSTRACT FROM AUTHOR]

The green tea component (-)-epigallocatechin-3-gallate (EGCG) has been shown to sensitize many different types of cancer cells to anticancer drug-induced apoptosis, although it protects against non-cancerous primary cells against toxicity from certain conditions such as exposure to arsenic (As) or ultraviolet irradiation. Here, we found that EGCG promotes As-induced toxicity of primary-cultured bovine aortic endothelial cells (BAEC) at doses in which treatment with each chemical alone had no such effect. Increased cell toxicity was accompanied by an increased condensed chromatin pattern and fragmented nuclei, cleaved poly(ADP-ribose) polymerase (PARP), activity of the pro-apoptotic enzymes caspases 3, 8 and 9, and Bax translocation into mitochondria, suggesting the involvement of an apoptotic signaling pathway. Fluorescence activated cell sorting analysis revealed that compared with EGCG or As alone, combined EGCG and As (EGCG/As) treatment significantly induced production of reactive oxygen species (ROS), which was accompanied by decreased catalase activity and increased lipid peroxidation. Pretreatment with N-acetyl-L-cysteine or catalase reversed EGCG/As-induced caspase activation and EC toxicity. EGCG/As also increased the phosphorylation of c-Jun N-terminal kinase (JNK), which was not reversed by catalase. However, pretreatment with the JNK inhibitor SP600125 reversed all of the observed effects of EGCG/As, suggesting that JNK may be the most upstream protein examined in this study. Finally, we also found that all the observed effects by EGCG/As are true for other types of EC tested. In conclusion, this is firstly to show that EGCG sensitizes non-cancerous EC to As-induced toxicity through ROS-mediated apoptosis, which was attributed at least in part to a JNK-activated decrease in catalase activity.