With plenty of stocks newly listed in the Chinese stock market everyday, it becomes more and more important for managers and governess to examine the trend of core competencies for these companies. ...Since most companies of newly listed stocks are small to medium-sized enterprises, existing methods are not capable enough to evaluate their competitiveness. To provide an understanding for the trend of core competencies in the Chinese market, this article conducts a concurrent comprehensive evaluation and active learning methodology to analyze the newly listed stocks in SSE (Shanghai Stock Exchange Composite Index) and SZSE (Shenzhen Stock Exchange Component Index) from 2015 through 2017. There is an evidence that Number of Market Makers, Equity Financing Frequency and Executive Replacement Frequency are three main core competencies from 2015 through 2017. Authors contend that their findings in this paper question the quo of core competencies for small to medium-sized enterprises in the Chinese market.
Due to their high toxicity and ongoing bioaccumulation, mercury ions (Hg
) can cause significant harm to both the environment and human health. Therefore, rapid, accurate, and selective methods for ...Hg
detection are highly desirable. Herein, we present a simple method for depositing platinum nanoparticles (PtNPs) on graphene oxide (GO) to obtain graphene oxide-PtNPs (GO-PtNPs). The fabricated GO-PtNPs exhibit excellent peroxidase-like activity and high stability. Further, the GO-PtNPs nanozymes preferentially reduced Hg
, thereby inhibiting the catalytic activity. By monitoring the color change in the chromogenic substrate, Hg
can be detected within 15 min. With a detection limit of 88.3 pM, the GO-PtNPs system may be employed to detect Hg
in a linear range of 0.1 nM to 10 μM. The simplicity and low cost of the proposed approach as well as its applicability to complicated samples demonstrate its capacity for mercury sensing in environmental samples.
The concentration of selenium (Se) in agricultural products primarily depends on the concentration of Se in soil and the ability of plants to accumulate Se. Selenium deficiency not only leads to ...decreased body resistance, but also increases the risk of cancer. The form and concentration of bioavailable Se is important for diet. The present study was carried out via field experiment with wheat and broad beans in soil of different Se concentrations (0, 1.12, and 11.2 kg·ha−1), which was determined based on the national standard and the team’s previous experience. Results indicated that the concentration of Se in the edible organs of wheat was higher than in broad bean, while the enriched Se concentration in the root of broad bean was more than twice and three times higher than that of wheat at medium and high levels of Se, respectively. Selenomethionine, which accounted for over half of the total Se speciations, was the dominant species in the edible parts of the two crops, followed by Selenocystine and methylselenocysteine. Through the analysis of the rhizosphere soil, it was found that Fe-Mn oxide-bound Se exceeded 80% of the total Se. Additionally, there was a significant linear correlation between the Se content in the edible parts of the two crops and the Se content in the soil. Findings suggested that wheat was more favorable than broad beans as Se supplement crops in a Se-supplied field.
Inlet and outlet boundary conditions (BCs) play an important role in newly emerged image-based computational hemodynamics for blood flows in human arteries anatomically extracted from medical images. ...We developed physiological inlet and outlet BCs based on patients’ medical data and integrated them into the volumetric lattice Boltzmann method. The inlet BC is a pulsatile paraboloidal velocity profile, which fits the real arterial shape, constructed from the Doppler velocity waveform. The BC of each outlet is a pulsatile pressure calculated from the three-element Windkessel model, in which three physiological parameters are tuned by the corresponding Doppler velocity waveform. Both velocity and pressure BCs are introduced into the lattice Boltzmann equations through Guo’s non-equilibrium extrapolation scheme. Meanwhile, we performed uncertainty quantification for the impact of uncertainties on the computation results. An application study was conducted for six human aortorenal arterial systems. The computed pressure waveforms have good agreement with the medical measurement data. A systematic uncertainty quantification analysis demonstrates the reliability of the computed pressure with associated uncertainties in the Windkessel model. With the developed physiological BCs, the image-based computation hemodynamics is expected to provide a computation potential for the noninvasive evaluation of hemodynamic abnormalities in diseased human vessels.
System reliability is usually estimated through component reliability, which is commonly computed by the First Order Reliability Method (FORM). The FORM is computationally efficient, but may not be ...accurate for nonlinear limit-state functions. An alternative system reliability analysis method is proposed based on saddlepoint approximation. Unlike the FORM that linearizes limit-state functions in a transformed random space, the proposed method linearizes the limited-state functions without any transformation. After the linearization, the joint probability density of limit-state functions is estimated by the multivariate saddlepoint approximation. Without the nonnormal-to-normal transformation, the present method is more accurate than the FORM when the transformation increases the nonlinearity of limit-state functions. As demonstrated in the two examples, the new method is also as efficient as the FORM.
Nitric oxide (NO) stimulates cGMP synthesis by activating its intracellular receptor, soluble guanylyl cyclase (sGC). It is a currently prevailing concept that No and cGMP inhibits platelet function. ...However, the data supporting the inhibitory role of NO/sGC/cGMP in platelets have been obtained either in vitro or using whole body gene deletion that affects vessel wall function. Here we have generated mice with sGC gene deleted only in megakaryocytes and platelets. Using the megakaryocyte- and platelet-specific sGC-deficient mice, we identify a stimulatory role of sGC in platelet activation and in thrombosis in vivo. Deletion of sGC in platelets abolished cGMP production induced by either NO donors or platelet agonists, caused a marked defect in aggregation and attenuated secretion in response to low doses of collagen or thrombin. Importantly, megakaryocyte- and platelet-specific sGC deficient mice showed prolonged tail-bleeding times and impaired FeCl3-induced carotid artery thrombosis in vivo. Interestingly, the inhibitory effect of the NO donor SNP on platelet activation was sGC-dependent only at micromolar concentrations, but sGC-independent at millimolar concentrations. Together, our data demonstrate important roles of sGC in stimulating platelet activation and in vivo thrombosis and hemostasis, and sGC-dependent and -independent inhibition of platelets by NO donors.
Optimality principles have been applied in ecohydrological modeling to derive optimal vegetation properties and describe co-evolution states of vegetation and water cycle. Unfortunately, most ...existing optimality-based models only consider vertical vegetation-soil-water interactions on plot scale, without considering the lateral hydrological processes. This work aims to extend the field-scale Vegetation Optimality Model (VOM) to the watershed scale. Lateral flow is incorporated to VOM through a hierarchical strategy, establishing the Distributed Vegetation Optimality Model (DisVOM). The model is tested with long-tem flux measurements in the Walnut Gulch watershed, a United States Agricultural Research Service (US-ARS) experimental watershed in southern Arizona. The results indicate the model performance is acceptable for most of years, especially for the growing season. The seasonal dynamic of ET, soil water, and GPP demonstrate good consistency with observations. The model provides reasonable spatial distribution of ET and GPP, suggesting the model can discriminate the effect of lateral flow on water redistribution, and consequently on root water uptake, as well as carbon assimilation. The model could be a useful tool assessing the impact of climate change and human activities on vegetation and water cycle.
Earthquake-induced landslides are serious natural hazards that shocked us with tremendous casualties and great economic losses in many mountainous areas around the world. However, predicting and ...preventing the earthquake-induced landslides is very difficult due to the complicated relationship between seismic dynamics and coseismic landsliding. Comprehensive understanding of earthquake-induced landslides from the perspective of seismic dynamic mechanism remains inadequate at present. This study employs an elastoplastic spectral element method incorporating parallel computing and represents a realistic three-dimensional slope model via a semi-structured hexahedral mesh to investigate the dynamic failure characteristics of earthquake-induced landslides. Dynamic behaviours of slopes are simulated using a continuumbased approach with a Mohr-Coulomb yield criterion. Displacement fields are calculated using the shear strength reduction technique. Pseudo-static seismic loading is performed to assess the slope stability quantitatively and complex topography is taken into consideration. The Xinzhong landslide that occurred in Beichuan Country is one of destructively collapsing landslides triggered by the Wenchuan earthquake and is therefore selected as a case study for discussion. Three-dimensional visualization of the calculated results quantitatively demonstrated that the three-dimensional numerical model well reproduced the coseismic landsliding response and its essential dynamic failure pattern, which could not be purely captured by Geographic Information Systems (GIS) and Remote Sensing (RS) technologies and calculated using simply two-dimensional numerical model. The numerical results also showed that tensile and shear fractures had significant influences on the nature of the failed surface development. In addition, the presence of seismic loading in the slope could cause obvious disturbances for the slope stability. Comparative analysis indicated that the shear surface of the earthquake-induced slope was shorter and the tension crack surface was deeper than that of the normal gravity condition. Moreover, the landslide mainly occurred in the transition from the upper to lower part of the slope, indicating that the slope topography was one of the crucial factors resulting in slope failure. Although the model was constructed without the presence of a pre-existing failure surface, comparative analysis addressed that the failure surface obtained by the numerical simulation was in close agreement with that by the post-failure investigations. The results could provide insight into better understanding of the relationship between landslide and seismic dynamic mechanism. The study has practical significance for the effective prevention and mitigation of earthquake-induced landslide hazards.
The antioxidant enzyme GPX3 is a selenoprotein that transports selenium in blood and maintains its levels in peripheral tissues. Aberrant GPX3 expression is strongly linked to the development of some ...tumors. However, there is a scarcity of studies examining the pan-cancer expression patterns and prognostic relevance of GPX3.
GPX3 expression levels in normal tissues and multiple tumors were analyzed using TCGA, CCLE, GTEx, UALCAN and HPA databases. Forest plots and KM survival curves were utilized to evaluate the correlation between GPX3 expression and the outcome of tumor patients. The prognostic value of GPX3 in LGG was assessed utilizing the CGGA datasets, and that in STAD was tested by TCGA and GEO databases. A nomogram was then constructed to predict OS in STAD using R software. Additionally, the impact of GPX3 on post-chemoradiotherapy OS in patients with LGG and STAD was evaluated using the KM method. The multiplicative interaction of GPX3 expression, chemotherapy and radiotherapy on STAD and LGG was analyzed using logistic regression models. The correlation of GPX3 with the immune infiltration, immune neoantigens and MMR genes were investigated in TCGA cohort.
GPX3 exhibited downregulation across 21 tumor types, including STAD, with its decreased expression significantly associated with improved OS, DFS, PFS and DSS. Conversely, in LGG, low levels of GPX3 expression were indicative of a poorer prognosis. Univariate and multivariate Cox models further identified GPX3 as an independent predictor of STAD, and a nomogram based on GPX3 expression and other independent factors showed high level of predictive accuracy. Moreover, low GPX3 expression and chemotherapy prolonged the survival of STAD. In LGG patients, chemoradiotherapy, GPX3 and chemotherapy, and GPX3 and chemoradiotherapy may improve prognosis. Our observations reveal a notable connection between GPX3 and immune infiltration, immune neoantigens, and MMR genes.
The variations in GPX3 expression are linked to the controlling tumor development and could act as a promising biomarker that impacts the prognosis of specific cancers like STAD and LGG.
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