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Owing to the unique electronic structure, kagome materials AV3Sb5 (A=K, Rb, Cs) provide a fertile platform of quantum phenomena such as the strongly correlated state and topological Dirac band. It is well known that RbV3Sb5 exhibits a 2×2 unconventional charge density wave (CDW) state at low temperature, and the mechanism is controversial. Here, by using scanning tunneling microscopy/spectroscopy (STM/STS), we successfully manipulated the CDW state in the Sb plane of RbV3Sb5, and realized a new √ 3×√ 3 modulation together with the ubiquitous 2×2 period in the CDW state of RbV3Sb5. The work provides a new understanding of the collective quantum ground states in the kagome materials.

OBJECTIVE: To formulate a nomogram to predict the risk of one-year mortality after percutaneous coronary intervention (PCI) based on a large-scale real-world Asian cohort. METHODS: This study cohort included consecutive patients undergoing PCI in the National Center for Cardiovascular Diseases of China. The endpoint was all-cause mortality. Least absolute shrinkage and selection operator Cox regression and backward stepwise regression were used to select potential risk factors. A nomogram based on the predictors was accordingly constructed to predict one-year mortality. The performance of the nomogram was evaluated. Patients were stratified into low-, intermediate- and high-risk groups according to the tertile points in the nomogram and compared by the Kaplan-Meier analysis. RESULTS: A total of 9603 individuals were included in this study and randomly divided into the derivation cohort (60%) and the validation cohort (40%). Six variables were selected to formulate the nomogram, including age, renal insufficiency, cardiac dysfunction, previous cerebrovascular disease, previous PCI, and TIMI 0–1 before PCI. The area under the curve of this nomogram regarding one-year mortality risks were 0.792 and 0.754 in the derivation cohort and validation cohort, respectively. Kaplan-Meier curve successfully stratified the patients according to three risk groups. This nomogram calibrated well and exhibited satisfactory clinical utility in the decision curve analysis. CONCLUSIONS: This study developed and validated a simple-to-use nomogram predicting one-year mortality risk in Asian patients undergoing PCI and could help clinicians make risk-dependent decisions.

A facile method for the quantitative preparation of silver dibenzo-fused corrole Ag-1 is described. In contrast to the saddle conformation resolved by single crystal X-ray analysis for Ag-1 , it adopts an unprecedented domed geometry, with up- and down-orientations, when adsorbed on Ag(111) surface. Sharp Kondo resonances near Fermi level, both at the corrole ligand and the silver center, were observed by cryogenic STM, with relatively high Kondo temperature (172 K), providing the first direct spectroscopic evidence for a non-innocent Ag II -corrole •2- species. Further investigation validates that benzene ring fusion and molecule-substrate interactions play pivotal roles in enhancing Ag (4d x2-y2 )-corrole (π) orbital interactions, thereby stabilizing the open-shell singlet Ag II -corrole •2- on Ag(111) surface. Moreover, this strategy used for constructing metal-free benzene-ring fused corrole ligand gives rise to inspiration of designing novel metal-corrole compound which could be applied to the research of multichannel molecular spintronics devices for data storage and logic gates.

Objective To develop and validate a model to predict seizure freedom in children undergoing cerebral hemispheric surgery for the treatment of drug-resistant epilepsy. Methods We analyzed 1267 hemispheric surgeries performed in pediatric participants across 32 centers and 12 countries to identify predictors of seizure freedom at 3 months after surgery. A multivariate logistic regression model was developed based on 70% of the dataset (training set) and validated on 30% of the dataset (validation set). Missing data were handled using multiple imputation techniques. Results Overall, 817 of 1237 (66%) hemispheric surgeries led to seizure freedom (median follow-up = 24 months), and 1050 of 1237 (85%) were seizure-free at 12 months after surgery. A simple regression model containing age at seizure onset, presence of generalized seizure semiology, presence of contralateral 18-fluoro-2-deoxyglucose-positron emission tomography hypometabolism, etiologic substrate, and previous nonhemispheric resective surgery is predictive of seizure freedom (area under the curve = .72). A Hemispheric Surgery Outcome Prediction Scale (HOPS) score was devised that can be used to predict seizure freedom. Significance Children most likely to benefit from hemispheric surgery can be selected and counseled through the implementation of a scale derived from a multiple regression model. Importantly, children who are unlikely to experience seizure control can be spared from the complications and deficits associated with this surgery. The HOPS score is likely to help physicians in clinical decision-making.

Excitons in solid state are bosons generated by electron-hole pairs as the Coulomb screening is sufficiently reduced. The exciton condensation can result in exotic physics such as super-fluidity and insulating state. In charge density wave (CDW) state, 1T-TiSe2 is one of the candidates that may host the exciton condensation. However, to envision its excitonic effect is still challenging, particularly at the two-dimensional limit, which is applicable to future devices. Here, we realize the epitaxial 1T-TiSe2 bilayer, the two-dimensional limit for its 2 × 2 × 2 CDW order, to explore the exciton-associated effect. By means of high-resolution scanning tunneling spectroscopy and quasiparticle interference, we discover an unexpected state residing below the conduction band and right within the CDW gap region. As corroborated by our theoretical analysis, this mysterious phenomenon is in good agreement with the electron-exciton coupling. Our study provides a material platform to explore exciton-based electronics and opto-electronics.

The superconducting proximity effect (SPE) induces a superconductivity transition in otherwise non-superconducting thin films in proximity with a superconductor. The SPE usually occurs in real space and decays exponentially with film thickness. Herein, an abnormal SPE in a topological insulator (TI)/superconductor heterostructure is unveiled, which is attributed to the topologically protected surface state. Surprisingly, such abnormal SPE occurs in momentum space regardless of the TI film thickness, as long as the topological surface states are robust and form a continuous conduction loop. Combining transport measurements and scanning tunneling microscopy/spectroscopy techniques, the SPE in Bi

ObjectiveThis study was undertaken to determine whether the vertical parasagittal approach or the lateral peri-insular/peri-Sylvian approach to hemispheric surgery is the superior technique in achieving long-term seizure freedom.MethodsWe conducted a post hoc subgroup analysis of the HOPS (Hemispheric Surgery Outcome Prediction Scale) study, an international, multicenter, retrospective cohort study that identified predictors of seizure freedom through logistic regression modeling. Only patients undergoing vertical parasagittal, lateral peri-insular/peri-Sylvian, or lateral trans-Sylvian hemispherotomy were included in this post hoc analysis. Differences in seizure freedom rates were assessed using a time-to-eventmethod andcalculated using the Kaplan-Meier survival method.ResultsData for 672 participants across 23 centers were collected on the specific hemispherotomy approach. Of these, 72 (10.7%) underwent vertical parasagittalhemispherotomy and 600 (89.3%) underwent lateral peri-insular/peri-Sylvian or trans-Sylvian hemispherotomy. Seizure freedom was obtained in 62.4% (95% confidence interval [CI]=53.5%-70.2%) of the entire cohort at 10-year follow-up. Seizure freedom was 88.8% (95% CI=78.9%-94.3%) at 1-year follow-up and persisted at 85.5% (95% CI=74.7%-92.0%) across 5- and 10-year follow-up in the vertical subgroup. In contrast, seizure freedom decreased from 89.2% (95% CI=86.3%-91.5%) at 1-year to 72.1% (95% CI=66.9%-76.7%) at 5-year to 57.2% (95% CI=46.6%-66.4%) at 10-year follow-up for the lateral subgroup. Log-rank test found that vertical hemispherotomy was associated with durable seizure-free progression compared to the lateral approach (p=.01). Patients undergoing the lateral hemispherotomy technique had a shorter time-to-seizure recurrence (hazard ratio=2.56, 95% CI=1.08-6.04, p=.03) and increased seizure recurrence odds (odds ratio=3.67, 95% CI=1.05-12.86, p=.04) compared to those undergoing the vertical hemispherotomy technique.SignificanceThis pilot study demonstrated more durable seizure freedom of the vertical technique compared to lateral hemispherotomy techniques. Further studies, such as prospective expertise-based observational studies or arandomized clinical trial, are required to determine whether a vertical approach to hemispheric surgery provides superior long-term seizure outcomes.

van der Waals SnI(2) Monolayers In article number 2100009, Ping Zhang, Shao‐Chun Li, and co‐workers demonstrate the direct growth of van der Waals SnI(2) monolayer, a new semiconducting material. The SnI(2) monolayer exhibits a band gap of 2.9 eV, and an indirect‐ to direct‐band gap transition occurs in the SnI2 bilayer, suggesting its potential application in future electronics/optoelectronics. [Image: see text]

Two‐dimensional (2D) van der Waals (vdW) materials have garnered considerable attention for their unique properties and potentials in a wide range of fields, which include nano‐electronics/optoelectronics, solar energy, and catalysis. Meanwhile, challenges in the approaches toward achieving high‐performance devices still inspire the search for new 2D vdW materials with precious properties. In this study, via molecular beam epitaxy, for the first time, the vdW SnI2 monolayer is successfully fabricated with a new structure. Scanning tunneling microscopy/spectroscopy characterization, as corroborated by the density functional theory calculation, indicates that this SnI2 monolayer exhibits a band gap of ≈2.9 eV in the visible purple range, and an indirect‐ to direct‐band gap transition occurs in the SnI2 bilayer. This study provides a new semiconducting 2D material that is promising as a building block in future electronics/optoelectronics., The great application potentials and challenges in high‐performance devices inspire the search for new two‐dimensional (2D) van der Waals (vdW) materials. Via molecular beam epitaxy, the vdW SnI2 monolayer is successfully fabricated with a new structure. This SnI2 monolayer is a 2D semiconductor with thickness‐dependent properties, which is promising as a building block in future electronics/optoelectronics.

By using scanning tunneling microscopy, we investigated the electronic evolution of T d-WTe2 via in-situ surface alkali K atoms deposition. The T d-WTe2 surface is electron doped upon K deposition, and as the K coverage increases, two gaps are sequentially opened near Fermi energy, which probably indicates that two phase transitions concomitantly occur during electron doping. The two gaps both show a dome-like dependence on the K coverage. While the bigger gap shows no prominent dependence on the magnetic field, the smaller one can be well suppressed and thus possibly corresponds to the superconducting transition. This work indicates that T d-WTe2 exhibits rich quantum states closely related to the carrier concentration.

A facile method for the quantitative preparation of silver dibenzo-fused corrole Ag-1 is described. In contrast to the saddle conformation resolved by single-crystal X-ray analysis for Ag-1, it adopts an unprecedented domed geometry, with up and down orientations, when adsorbed on an Ag(111) surface. Sharp Kondo resonances near Fermi level, both at the corrole ligand and the silver center were observed by cryogenic STM, with relatively high Kondo temperature (172 K), providing evidence for a non-innocent Ag

The interfacial charge transfer from the substrate may influence the electronic structure of the epitaxial van der Waals (vdW) monolayers and thus their further technological applications. For instance, the freestanding Sb monolayer in puckered honeycomb phase ({\alpha}-antimonene), the structural analog of black phosphorene, was predicted to be a semiconductor, but the epitaxial one behaves as a gapless semimetal when grown on the Td-WTe2 substrate. Here, we demonstrate that interface engineering can be applied to tune the interfacial charge transfer and thus the electron band of epitaxial monolayer. As a result, the nearly freestanding (semiconducting) {\alpha}-antimonene monolayer with a band gap of ~170 meV was successfully obtained on the SnSe substrate. Furthermore, a semiconductor-semimetal crossover is observed in the bilayer {\alpha}-antimonene. This study paves the way towards modifying the electron structure in two-dimensional vdW materials through interface engineering., Comment: 18 pages, 4 figures

Two-dimensional (2D) ferromagnetic materials have been exhibiting promising potential in applications, such as spintronics devices. To grow epitaxial magnetic films on silicon substrate, in the single-layer limit, is practically important but challenging. In this study, we realized the epitaxial growth of MnSn monolayer on Si(111) substrate, with an atomically thin Sn/Si(111)-$2\sqrt{3}\times2\sqrt{3}$- buffer layer, and controlled the MnSn thickness with atomic-layer precision. We discovered the ferromagnetism in MnSn monolayer with the Curie temperature (Tc) of ~54 K. As the MnSn film is grown to 4 monolayers, Tc increases accordingly to ~235 K. The lattice of the epitaxial MnSn monolayer as well as the Sn/Si(111)-$2\sqrt{3}\times2\sqrt{3}$ is perfectly compatible with silicon, and thus an sharp interface is formed between MnSn, Sn and Si. This system provides a new platform for exploring the 2D ferromagnetism, integrating magnetic monolayers into silicon-based technology, and engineering the spintronics heterostructures., Comment: 12 pages, 3 figures, to appear in Chin. Phys. Lett. (Express Letters)

Background: A subset of pediatric epilepsy patients suffer from epilepsy syndromes related to multi-lobar or hemispheric epileptogenic networks and diseases. Most of these patients are refractory to anti-seizure drug treatment, resulting in persistent disabling seizures, neurocognitive delay and impaired quality of life. In well-selected patients, hemispheric surgery is associated with excellent seizure freedom rates and relatively low complication rates. Nevertheless, 30% of patients develop seizure recurrence after cerebral hemispheric surgery. The purpose of this study was to develop and validate a model to predict seizure freedom in children undergoing cerebral hemispheric surgery for the treatment of drug-resistant epilepsy. Methods: We analyzed 1237 hemispheric surgeries performed in pediatric patients across 31 centers and 12 countries to identify predictors of seizure freedom at 12 months after surgery. A multivariate logistic regression model was developed based on the entire dataset and its performance was evaluated based on cross-validation. Missing data was handled using multiple imputation techniques. Findings: Overall, 817/1237 (66%) hemispheric surgeries led to seizure freedom (median follow-up of 24 months), and 1050/1237 (85%) were seizure free at 12 months after surgery. The regression model containing age at seizure onset, presence of generalized seizure semiology, presence of contralateral 18-fluoro-2-deoxyglucose–positron emission tomography hypometabolism, etiologic substrate and previous non-hemispheric resective surgery were predictive of seizure freedom (AUC 0·72). A practical Hemispheric Surgery Outcome Prediction Scale (HOPS) score was devised based on these results that can be used to predict seizure freedom. Interpretation: Children most likely to benefit from hemispheric surgery can be selected and counselled through the implementation of a scale derived from a multiple regression model. Importantly, children who are unlikely to experience seizure control can be spared from the complications and deficits associated with this surgery. The HOPS score is likely to help physicians in clinical decision-making. Funding Statement: The authors stated: "None." Declaration of Interests: None of the authors has any conflict of interest to disclose. None of the authors have financial relationships relevant to this article. Gary W Mathern MD is partly supported by the Davies/Crandall Endowed Chair for epilepsy Research at UCLA. Dr. Phillip Pearl receives research support from the NIH, NSF, and Boston Healthcare Associates; royalty payments from Elsevier, Springer Pubs, and UpToDate; has served as a consultant for Agilis Biotherapeutics and GLG Health Care Council; and is Associate Editor for the Journal of Child Neurology and on the editorial boards of Annals Neurology, Epilepsia, Future Neurology, Music and Medicine, and Neurology. Dr. Jeffrey Ojemann is a shareholder of Therma Neurosciences, a grant recipient of the NIH/NSF, and serves on the advisory board for the Epilepsy Foundation of the Northwest. The views expressed in this article are not the official positions of any authors’ affiliated institutions. Ethics Approval Statement: The organizing center received IRB approval for this study and each contributing center obtained research ethics approval locally.

Chiral fermions in solid state feature "Fermi arc" states, connecting the surface projections of the bulk chiral nodes. The surface Fermi arc is a signature of nontrivial bulk topology. Unconventional chiral fermions with an extensive Fermi arc traversing the whole Brillouin zone have been theoretically proposed in CoSi. Here, we use scanning tunneling microscopy / spectroscopy to investigate quasiparticle interference at various terminations of a CoSi single crystal. The observed surface states exhibit chiral fermion-originated characteristics. These reside on (001) and (011) but not (111) surfaces with pi-rotation symmetry, spiral with energy, and disperse in a wide energy range from ~-200 to ~+400 mV. Owing to the high-energy and high-space resolution, a spin-orbit coupling-induced splitting of up to ~80 mV is identified. Our observations are corroborated by density functional theory and provide strong evidence that CoSi hosts the unconventional chiral fermions and the extensive Fermi arc states., Comment: 20 pages, 4 figures

The two-dimensional topological insulators (2DTI) host a full gap in the bulk band, induced by spin-orbit coupling (SOC) effect, together with the topologically protected gapless edge states. However, the SOC-induced gap is usually small, and it is challenging to suppress the bulk conductance and thus to realize the quantum spin Hall (QSH) effect. In this study, we find a novel mechanism to effectively suppress the bulk conductance. By using the quasiparticle interference (QPI) technique with scanning tunneling spectroscopy (STS), we demonstrate that the QSH candidate single-layer 1T'-WTe$_2$ has a semi-metal bulk band structure with no full SOC-induced gap. Surprisingly, in this two-dimensional system, we find the electron interactions open a Coulomb gap which is always pinned at the Fermi energy (E$_F$). The opening of the Coulomb gap can efficiently diminish the bulk state at the E$_F$ and is in favor of the observation of the quantized conduction of topological edge states., 13 pages, 4 figures

Allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester, diallyl thiosulfinate) is the main biologically active ingredient in garlic. The present study investigated the protective effect of allicin against cardiomyocyte apoptosis that was induced by ischemia in vitro and the potential molecular mechanisms that were involved in this antiapoptotic effect. The results indicated that allicin increased H9c2 cell activity and attenuated the rate of apoptosis that was induced by ischemia/hypoxia. Intracellular calcium concentrations significantly decreased in the allicin-treated groups. Bax expression significantly decreased, and Bcl-2 expression increased in allicin-treated rats. Nitric oxide blockade significantly inhibited these effects. Allicin also increased the activity of SOD and NO release and decreased MDA levels. Allicin significantly increased the expression of eNOS, Nrf2, and HO-1 proteins. Collectively, these findings demonstrate that allicin protects H9c2 cells against apoptosis, and this protective effect appears to occur via eNOS/NO pathway-mediated antioxidant activity.

Dedifferentiated liposarcoma (DDLS) is characterized at the molecular level by amplification of genes within 12q13-15 including MDM2 and CDK4 . However, other than FNCLCC grade, prognostic markers are limited. We aim to identify molecular prognostic markers for DDLS to help risk stratify patients. To this end, we studied 49 cases of DDLS in our institutional archives and performed cytogenomic microarray analysis on 47 cases. Gene copy numbers for 12 loci were evaluated and correlated with outcome data retrieved from our institutional electronic medical records. Using cut point analysis and comparison of Kaplan-Meier survival curves by log rank tests, high amplification levels of MDM2 (>38 copies) and CDK4 (>30 copies) correlated with decreased disease free survival (DFS) ( P = . 0168 and 0.0169 respectively) and disease specific survival (DSS) ( P = . 0082 and 0.0140 respectively). Additionally, MDM2 and CDK4 showed evidence of a synergistic effect so that each additional copy of one enhances the effect on prognosis of each additional copy of the other for decreased DFS ( P = . 0227, 0.1% hazard). High amplification of JUN (>16 copies) also correlated with decreased DFS ( P = . 0217), but not DSS. The presence of copy number alteration at 3q29 correlated with decreased DSS ( P = . 0192). The presence of >10 mitoses per 10 high power fields and FNCLCC grade 3 also correlated with decreased DFS ( P = . 0310 and 0.0254 respectively). MDM2 and CDK4 gene amplification levels, along with JUN amplification and copy alterations at 3q29, can be utilized for predicting outcome in patients with DDLS.

Understanding the interplay between superconductivity and charge-density wave (CDW) in NbSe2 is vital for both fundamental physics and future device applications. Here, combining scanning tunneling microscopy, angle-resolved photoemission spectroscopy and Raman spectroscopy, we study the CDW phase in the monolayer NbSe2 films grown on various substrates of bilayer graphene (BLG), SrTiO3(111), and Al2O3(0001). It is found that the two stable CDW states of monolayer NbSe2 can coexist on NbSe2/BLG surface at liquid-nitrogen temperature. For the NbSe2/SrTiO3(111) sample, the unidirectional CDW regions own the kinks at ±41 meV and a wider gap at 4.2 K. It is revealed that the charge transfer from the substrates to the grown films will influence the configurations of the Fermi surface, and induce a 130 meV lift-up of the Fermi level with a shrink of the Fermi pockets in NbSe2/SrTiO3(111) compared with the NbSe2/BLG. Combining the temperature-dependent Raman experiments, we suggest that the electron-phonon coupling in monolayer NbSe2 dominates its CDW phase transition.

Black phosphorus (BP) has recently attracted considerable attention due to its unique structure and fascinating optical and electronic properties as well as possible applications in photothermal agents. However, its main drawback is rapid degradation in ambient environments of H2O and O2, which has led to much research on the improvement of its stability. Unfortunately, this research has not shown great improvement in carrier mobilities. Here, we perform scanning tunneling microscopy observations of few-layer BP (FLBP) sheets exfoliated in ultrahigh vacuum and reveal, for the first time, the existence of lattice oxygen introduced during crystal growth. As a proof-of-concept application, hydrogenation is conducted to remove the lattice oxygen atoms followed by phosphorization, which repairs the phosphorous vacancies caused by mechanical exfoliation and hydrogenation. The resulting FLBP sheets show high ambipolar field-effect mobilities of 1374 cm2 V–1 s–1 for holes and 607 cm2 V–1 s–1 for electrons at 2 K....

Molecular motors are nanoscale machines that convert external energies into controlled mechanical movements. In supramolecular motors, the rotator and stator are held together mechanically, and thus the rotation can be essentially barrier free when molecular conformation is negligible. However, nearly all the supramolecular motors appeared in solutions or host-guest complexes. Surface-mounted supramolecular motors have rarely been addressed, even though they are easily manipulated by external fields. Here we report a surface-mounted supramolecular motor assembled by charge states and hydrogen bonds. On a graphite surface, individual ethanol clusters can be charged with a scanning tunneling microscopy tip and then trap the ethanol chains with a permanent dipole moment. Serving as a rotator, the trapped ethanol chains rotate around a charged cluster driven by the inelastic tunneling electrons. Random rotation in clockwise or anticlockwise direction occurs in the chiral molecular chains through chiral flipping. Directional rotation with clockwise chirality can be realized by introducing a chiral branch to the near end of ethanol chains to suppress the chiral flipping with steric hindrance.

Three-dimensional (3D) Dirac and Weyl semimetals are quantum states that have emerged in physics recently. But their intrinsic transport properties are quite elusive because of either the coexistence of Schr\"odinger fermions or the deviation of linear dispersion at Fermi level in previously proposed Dirac and Weyl semimetals. Here, we provide the theoretical and experimental evidences of an intrinsic Dirac state in the quaternary chalcogenide $\mathrm{C}{\mathrm{u}}_{2}\mathrm{HgSnS}{\mathrm{e}}_{4}$ that has bared linear dispersions in conduction bands. Scanning tunneling spectroscopy reveals the quadratic energy-dependent density of states within an extremely large energy range $(\ensuremath{\sim}400\phantom{\rule{0.16em}{0ex}}\mathrm{meV})$ on conduction bands of $\mathrm{C}{\mathrm{u}}_{2}\mathrm{HgSnS}{\mathrm{e}}_{4}$, which is self-consistent with linear dispersion detected by angle-resolved photoemission spectroscopy. In electron-doped $\mathrm{C}{\mathrm{u}}_{2}\mathrm{HgSnS}{\mathrm{e}}_{4}$, positive magnetoresistance at low magnetic field $B(l2.5\phantom{\rule{0.16em}{0ex}}\mathrm{T})$ and negative magnetoresistance under high $B$ are observed, which is attributed to the chiral anomaly effect. However, conventional negative magnetoresistance is observed in hole-doped $\mathrm{C}{\mathrm{u}}_{2}\mathrm{HgSnS}{\mathrm{e}}_{4}$, which is attributed to weak localization broken by $B$. Remarkably, the carrier mobility has a ${10}^{5}$-fold decrease when the Fermi level is adjusted from conduction to valence bands. Our results suggest that $\mathrm{C}{\mathrm{u}}_{2}\mathrm{HgSnS}{\mathrm{e}}_{4}$ not only provides a playground for exploring intrinsic properties of 3D Dirac fermions but also is promising for developing high-speed, low-dissipation electronic devices.

Metallization of 1T-TaS_{2} is generally initiated at the domain boundary of a charge density wave (CDW), at the expense of its long-range order. However, we demonstrate in this study that the metallization of 1T-TaS_{2} can be also realized without breaking the long-range CDW order upon surface alkali doping. By using scanning tunneling microscopy, we find the long-range CDW order is always persisting, and the metallization is instead associated with additional in-gap excitations. Interestingly, the in-gap excitation is near the top of the lower Hubbard band, in contrast to a conventional electron-doped Mott insulator where it is beneath the upper Hubbard band. In combination with the numerical calculations, we suggest that the appearance of the in-gap excitations near the lower Hubbard band is mainly due to the effectively reduced on-site Coulomb energy by the adsorbed alkali ions.

Topological nodal-line semimetals with exotic quantum properties are characterized by symmetry-protected line-contact bulk band crossings in the momentum space. However, in most of identified topological nodal-line compounds, these topological non-trivial nodal lines are enclosed by complicated topological trivial states at the Fermi energy ($E_F$), which would perplex their identification and hinder further applications. Utilizing angle-resolved photoemission spectroscopy and first-principles calculations, we provide compelling evidence for the existence of Dirac nodal-line fermions in the monoclinic semimetal SrAs$_3$, which are close to $E_F$ and away from distraction of complex trivial Fermi surfaces or surface states. Our calculation indicates that two bands with opposite parity are inverted around \emph{Y} near $E_F$, which results in the single nodal loop at the $\Gamma$-\emph{Y}-\emph{S} plane with a negligible spin-orbit coupling effect. We track these band crossings and then unambiguously identify the complete nodal loop quantitatively, which provides a critical experimental support to the prediction of nodal-line fermions in the CaP$_3$ family of materials. Hosting simple topological non-trivial bulk electronic states around $E_F$ and no interfering with surface states on the natural cleavage plane, SrAs$_3$ is expected to be a potential platform for topological quantum state investigation and applications.

Collection and management of clinical data for administration and analysis is a time-consuming and complex task, especially when multiple data providers been involved. Even if people are willing to take on the burden for it, there is still no mature solution to protect data privacy for distributed data providers. Distributed ledger is an emerging technology that supports decentralized data sharing and management. Based on this, we present a platform which enables distributed and truthful data collection and serves privacy-preserving needs in clinical data management. Our system, built on Hyperledger Fabric, used smart contract to execute data aggregation and provide basic analysis methods. The system used ledger and world status to record data access history and other metadata. This decentralized platform enables data providers to proactively share and protect their data, Thus can simplify clinical data collection procedure and promote efficient collaboration between providers.

Natural Language Processing (NLP) is a key technique to automate Business Process Management (BPM) at different levels. The performance of existing NLP based BPM methods suffer from the limited accuracy of Part of Speech (POS) tagging, which is a key step in NLP pipelines. Note that the performance of POS tagging highly depends on the domain of annotated training data. However, most state-of-the-art POS taggers are trained from corpus in newswire domain which usually have different syntax features with business process description (BPD). The syntax features of BPD domain include usually starting with an imperative verb and containing numerous out-of-vocabulary (OOV) words. In this paper, we propose a novel POS tagging framework to tackle these problems. The main idea is that syntax feature of starting with imperative verb could be studied by enhancing the proportion of correctly POS-annotated imperative sentences in the training data. The trained POS tagger could reduce the overall POS tagging error by nearly 12% compared with newswire trained POS tagger. For verbs which are key words in BPD, the tagging precision could be increased by 27%. The lexical ambiguity caused by OOV words is solved by extracting local contextual knowledge out of images which are attached to help users understand the process better. Experimental results show that the overall POS tagging accuracy could be increased by nearly 10% with contextual OOV knowledge.

Atomically thin two-dimensional (2D) crystals have gained tremendous attentions owing to their potential impacts to the future electronics technologies, as well as the exotic phenomena emerging in these materials. Monolayer of {\alpha} phase Sb ({\alpha}-antimonene) that shares the same puckered structure as black phosphorous, has been predicted to be stable with precious properties. However, the experimental realization still remains challenging. Here, we successfully grow high-quality monolayer {\alpha}-antimonene, with the thickness finely controlled. The {\alpha}-antimonene exhibits great stability upon exposure to air. Combining scanning tunneling microscope, density functional theory calculations and transport measurement, it is found that the electron band crossing the Fermi level exhibits a linear dispersion with a fairly small effective mass, and thus a good electrical conductivity. All of these properties make the {\alpha}-antimonene promising in the future electronic applications., Comment: 14 pages, 5 figures