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This study explores the distress risk anomaly--the tendency for stocks with high credit risk to perform poorly--among 38 countries over two decades. We find a strongly negative relationship between default probabilities and equity returns concentrated among lowcapitalization stocks in developed countries in North America and Europe. Although risk-based explanations provide a poor account of these patterns, several pieces of evidence point to a behavioral interpretation, suggesting that stocks of firms in financial distress are temporarily overpriced. [ABSTRACT FROM AUTHOR]

Background: Recently, the combination of immunotherapy with chemotherapy has been recommended as first-line treatment of metastatic gastric/gastroesophageal junction (G/GEJ) in the clinical guidelines of many countries; the therapeutic potential of this application needs to be further investigated for neoadjuvant therapy of advanced G/GEJ cancer patients. Methods: We performed a prospective, single-arm, open-label, phase 2 trial of the PD-1 inhibitor tislelizumab combined with S-1 plus oxaliplatin (SOX) in patients with advanced LAG/GEJ cancer. All patients underwent the threecycle (21 days/cycle) treatment except for one patient who underwent two cycles. The primary endpoints were tumor major pathology response (MPR) and other events of tumor response assessed by the RECIST 1.1 and Becker criteria. Moreover, we constructed a few-shot learning model to predict the probability of MPR, which could screen those patients who might benefit from the neoadjuvant immunotherapy-chemotherapy scheme. This study was registered at https://clinicaltrials.gov/ct2/show/NCT0-4890392. Results: Thirty-two patients were enrolled; 17 patients (53.1%) achieved MPR (=10% viable tumor cells) after treatment, and among them, 8 (25.0%) had a pathological complete response (pCR). The 1-year overall survival (OS) rate was 91.4% and the 1-year recurrence-free survival (RFS) rate was 90.0%. Adverse events occurred in 24 patients (65.6%) and grade III-IV adverse events were observed in 4 patients (12.5%) during the neoadjuvant period. Furthermore, we found commonly used preoperative assessment tools such as CT and EUS, which presented limited accuracy of tumor therapeutic response in this study; thus, we developed a therapeutic response predictive model that consisted of TNFa, IFNg, IL-10, CD4, and age of patient, and the AUC of this FSL model was 0.856 (95% CI: 0.823-0.884). Discussion: Our study showed that the neoadjuvant PD-1 inhibitor tislelizumab combined with SOX had promising application potential and presented no increasing treatment-related adverse events in patients with advanced G/GEJ cancer. Moreover, the predictive model could help therapists to evaluate the therapeutic response of this scheme accurately. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (ZIBs) are considered as desirable large-scale energy storage systems because of their environment friendliness and low cost. However, the development of ZIBs with stable performance still faces many obstacles before becoming viable for commercial applications. Herein, V2O5·nH2O nanobelts with uniform size derived from highly conductive V2CTx MXene (VC-ZVO) are designed and synthesized as cathodes for ZIBs via simultaneous ion intercalation and oxidation. Thanks to the pre-intercalated Zn2+ and the ubiquitous interfaces between ZVO and the conductive network composed of the remaining V2CTx and carbon, the charge redistribution in the active/conductive heterostructure leads to weakening of electrostatic interactions, quick zinc-ion insertion/extraction, and structural stability. Accordingly, the VC-ZVO electrode shows ultrastable cycling performance and high rate capacities for ZIBs, presenting no fading capacity at 0.1 A g-1 and 96.4% capacity retention over 8000 cycles at 10 A g-1. Further studies on the electrochemical kinetics and reaction mechanism elucidate faster Zn2+ diffusion and the high reversibility of VC-ZVO ZIBs. The revelation of the origin of the improved Zn2+-storage provides distinctive ideas for the enhancement of V-based electrodes and the development of a new type of cathode. [ABSTRACT FROM AUTHOR]

For the first time, a 3D Prussian blue analogue (PBA) with well-defined spatial organization is fabricated by using a nickel hydroxide array as a precursor. The nickel hydroxide arrays are synthesized in titanium foil and reacted with K3[Fe(CN)6]. The plate-like morphology of the nickel hydroxide is perfectly preserved and combined with abundant PBA nanocubes. After phosphidation at 350 °C, the obtained sample demonstrated excellent hydrogen evolution reaction (HER) activity in both acid and alkaline solutions to reach a current density of 10 mA cm-2 with an overpotential of only 70 and 121 mV, respectively. With an overpotential of 266 mV, it can reach a larger current density of 500 mA cm-2 in acid. The efficient HER activity of the obtained sample is mainly ascribed to its structural advantage with various active metal sites derived from the nickel hydroxide and PBA precursor. In addition, long-term stability measurements have verified the good performance of the obtained sample in acid and alkaline solutions. An increment of overpotential of only 8 and 9 mV is observed, in the acid and alkaline solutions respectively. Beyond these assets, it is supposed that the strategy to synthesize 3D PBA arrays from nickel hydroxide can be extended to other metal-organic frameworks arrays for more electrochemical applications. [ABSTRACT FROM AUTHOR]

Considering the complexity of lane changing using automated vehicles and the frequency of turning lanes in city settings, this paper aims to generate an accelerated lane-changing trajectory using vehicle-to-vehicle collaboration (V2VC). Based on the characteristics of accelerated lane changing, we used a polynomial method and cooperative strategies for trajectory planning to establish a lane-changing model under different degrees of collaboration with the following vehicle in the target lane by considering vehicle kinematics and comfort requirements. Furthermore, considering the shortcomings of the traditional elliptical vehicle and round vehicle models, we established a rectangular vehicle model with collision boundary conditions by analysing the relationships between the possible collision points and the outline of the vehicle. Then, we established a simulation model for the accelerated lane-changing process in different environments under different degrees of collaboration. The results show that, by using V2VC, we can achieve safe accelerated lane-changing trajectories and simultaneously satisfy the requirements of vehicle kinematics and comfort control. [ABSTRACT FROM AUTHOR]

Oncogenic KRAS contributes to malignant transformation, antiapoptosis, and metastasis in multiple human cancers, such as lung, colon, and pancreatic cancers and melanoma. MicroRNAs (miRNAs) are endogenous 18- to 25-nucleotide noncoding small RNAs that regulate gene expression in a sequence-specific manner via the degradation of target mRNAs or inhibition of protein translation. In the present study, using array-based miRNA profiling in IMR90 and MCF10A cells expressing oncogenic KRAS, we identified that the expression of the microRNA 200 (mir-200) family was suppressed by KRAS activation and that this suppression was mediated by the transcription factors JUN and SP1 in addition to ZEB1. Restoration of mir-200 expression compromised KRAS-induced cellular transformation in vitro and tumor formation in vivo. In addition, we found that enforced expression of mir-200 abrogated KRAS-induced resistance to apoptosis by directly targeting the antiapoptotic gene BCL2. Finally, mir-200 was able to antagonize the epithelial-mesenchymal transition (EMT) driven by mutant KRAS. Collectively, our results suggest that repression of endogenous mir-200 expression is one of the important cellular responses to KRAS activation during tumor initiation and progression. [ABSTRACT FROM AUTHOR]

The increasingly frequent extreme weather disasters caused by global climate change have attracted more attention to adverse weather's effect on infrastructure systems. This paper aims to establish an integrated approach to assessing adverse weather's effect on urban rail transit facilities and to provide decision makers with a powerful tool to analyze potential risks and allocate limited sources for risk management. First, fault tree analysis is used to understand where the risks are, how the risks will occur, and what factors have the most significant effects by analyzing all possible basic events. All wind-, rain-, and snow-related adverse weather, along with human-related factors (construction leftover problems and design drawbacks), are found to potentially cause great risks. Adverse impact scenarios are summarized based on the fault tree analysis. Next, an analytic hierarchical process (AHP)-based fuzzy synthetic evaluation model is established to assess the risk level based on an evaluation index system. AHP is used to calculate the weights between the indices for each adverse weather factor. A fuzzy synthetic evaluation process is then carried out to identify the risk level of an evaluation target, an urban rail transit station, or line section. A case study on the Beijing URT Line 8 Olympic Center Station is conducted to illustrate the process of evaluation. The results show that the risk level is high and it becomes acceptable only after countermeasures are taken. Potential countermeasures regarding facility capacity, protection area management, and monitoring/inspection are then briefly discussed. [ABSTRACT FROM AUTHOR]

We demonstrated an environmentally friendly and efficient route for the preparation of titanium oxide (TiO2) nanoparticles-reduced graphene oxide composite with a one-step hydrothermal method using glucose as the reducing agent. The reducing process was accompanied by generation of TiO2nanoparticles. The structure and composition of the nanocomposite has been characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, thermal gravimetric analysis and atomic force microscopy. The TiO2-coated RGO nanocomposite was shown to improve the photocatalytic property of TiO2, which would be promising for practical applications in future nanotechnology. [ABSTRACT FROM AUTHOR]

We use one molecule of ethylene diamine as a connecting arm to combine two molecules of 5,6-dehydronorcantharidin. Then, ten novel norcantharidin derivatives were synthesized in a single step by the [3 + 2] 1,3-dipolar cycloaddition reaction with oxime or hydrazone in the presence of chloramine-T, which is simpler than the conventional method. J. Heterocyclic Chem., 2011. [ABSTRACT FROM AUTHOR]

Neurogenesis occurs in discrete regions of normal brains of adult mammals including humans, and is induced in response to brain injury and neurodegenerative disease. Whether intracerebral hemorrhage can also induce neurogenesis in human brain is unknown. Specimens were obtained from patients with primary intracerebral hemorrhage undergoing surgical evacuation of an intracerebral hematoma, and evaluated by two-photon laser scanning confocal microscopy. We found that neural stem/progenitor cell-specific protein markers were expressed in cells located in the perihematomal regions of the basal ganglia and parietal lobe of the adult human brain after primary intracerebral hemorrhage (n=5). Cells in this region also expressed cell proliferation markers, which colocalized to the same cells that expressed neural stem/progenitor cell-specific proteins. Our data suggest that intracerebral hemorrhage induces neurogenesis in the adult human brain.Journal of Cerebral Blood Flow & Metabolism (2008) 28, 1460–1468; doi:10.1038/jcbfm.2008.37; published online 30 April 2008 [ABSTRACT FROM AUTHOR]

The article studies the miscibility, crystallization behavior and intermolecular interactions in thermosetting polymer blends of novolac epoxy resin (EPN) and polyethylene glycol (PEG) using polarized optical microscopy and differential scanning calorimetry. According to the authors, the capability of PEG to crystallize in cured blends was different from that in uncured ones because of the topological effect of the highly crosslinking structure. The authors add that there were intermolecular hydrogen-bonding interactions between EPN and PEG in both cured and uncured blends based on the Fourier transform infrared spectroscopy results.

Experimental stroke in rodents stimulates neurogenesis and migration of newborn neurons from their sites of origin into ischemic brain regions. We report that in patients with stroke, cells that express markers associated with newborn neurons are present in the ischemic penumbra surrounding cerebral cortical infarcts, where these cells are preferentially localized in the vicinity of blood vessels. These findings suggest that stroke-induced compensatory neurogenesis may occur in the human brain, where it could contribute to postischemic recovery and represent a target for stroke therapy. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNT) are uniformly covered with copper hexacyanoferrate (CuHCF) via coprecipitation to form a core shell structure. The CuHCF thickness can be tuned from 10 nm to 30 nm by changing the CuHCF loading in the hybrids from 25% to 58%. The capacitive behavior is affected by the hydrated cation radius. In 1 mol l−1 KCl solution, CuHCF/CNT hybrids (46% CuHCF loading) show the largest specific capacitance of up to 989 F g−1 at a discharge density of 1 A g−1. The hybrids also possess superior rate capability with only 8.2% capacitance loss when increasing the discharge current from 1 to 20 A g−1. The superior capacitive performance of the hybrids in the K+-ion solution can be attributed to the smaller hydrated radius of the K+ ion, which will favor the diffusion of the cation within the CuHCF lattice, leading to a larger faradic current. Besides, the cyclic stability of the hybrids is surprising, with 89.7% capacitance retention after 10000 discharge/charge cycles. The CuHCF/CNT hybrids are combined with the reduced graphene oxides (RGOs) to construct an asymmetrical supercapacitor, and its potential window can reach up to 2.0 V. More importantly, this supercapacitor exhibits a high energy density of 60.4 Wh kg−1 at the power density of 0.5 kW kg−1. [ABSTRACT FROM AUTHOR]

How to use Pt economically and efficiently in the oxygen reduction reaction (ORR) is of theoretical and practical significance for the industrialization of the proton-exchange membrane fuel cells. In order to minimize Pt consumption and optimize the ORR performance, the ORR catalysts are recommended to be designed as a porous nanostructure. Herein, we report a one-pot solvothermal strategy to prepare PtPd dendritic nanocube cages via a galvanic replacement mechanism triggered by an I− ion. These PtPd alloy crystals are nanoporous, and uniformly dispersed on reduced graphene oxides (RGOs). The size of the PtPd dendritic nanocube cages can be easily tuned from 20–80 nm by controlling their composition. Their composition is optimized to be 1:5 Pt/Pd atomic ratio for these RGO-supported PtPd dendritic nanocages. This catalyst shows superior ORR performance with a specific activity of 2.01 mA cm−2 and a mass activity of 4.45 A mg−1 Pt, far above those for Pt/C catalysts (0.288 mA cm−2 for specific activity, and 0.21 A mg−1 Pt for mass activity). In addition to ORR activity, it also exhibits robust durability with almost negligible decay in ORR mass activity after 10 000 voltammetric cycling. [ABSTRACT FROM AUTHOR]

Heterostructures of atomically thin 2D materials could have improved physical, mechanical and chemical properties as compared to its individual components. Here we report, the effect of heterostructure coatings of hBN and MoS2 on the corrosion behavior as compared to coatings employing the individual 2D layer compositions. The poor corrosion resistance of MoS2 (widely used as wear resistant coating) can be improved by incorporating hBN sheets. Depending on the atomic stacking of the 2D sheets, we can further engineer the corrosion resistance properties of these coatings. A detailed spectroscopy and microscopy analysis has been used to characterize the different combinations of layered coatings. Detailed DFT based calculation reveals that the effect on the electrical properties due to atomic stacking is one of the major reasons for the improvement seen in corrosion resistance. [ABSTRACT FROM AUTHOR]

We demonstrate a one-pot thermoreduction approach towards the preparation of single-crystal Pt nanoplates, which were uniformly deposited on the reduced graphene oxide (RGO) using polyvinylpyrrolidone (PVP) as a stabilizer. The size of Pt nanoplates can be tuned from 6.8 to 10.1 nm by controlling Pt loading. The as-prepared Pt/PVP/RGO catalysts show high stability and activity towards the methanol oxidation reaction (MOR). Their MOR current can reach up to 401 mA mg−1 Pt and MOR current can maintain 89.4% of its initial value after 10 000 potential cycles. [ABSTRACT FROM AUTHOR]