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2D second‐order topological insulators (SOTIs) have sparked significant interest, but currently, the proposed realistic 2D materials for SOTIs are limited to nonmagnetic systems. In this study, for the first time, a single layer of chalcogenide CrSiTe3—an experimentally realized transition metal trichalcogenide is proposed with a layer structure—as a 2D ferromagnetic (FM) SOTI. Based on first‐principles calculations, this study confirms that the CrSiTe3 monolayer exhibits a nontrivial gapped bulk state in the spin‐up channel and a trivial gapped bulk state in the spin‐down channel. Based on the higher‐order bulk–boundary correspondence, it demonstrates that the CrSiTe3 monolayer exhibits topologically protected corner states with a quantized fractional charge (e3$\frac{e}{3}$) in the spin‐up channel. Notably, unlike previous nonmagnetic examples, the topological corner states of the CrSiTe3 monolayer are spin‐polarized and pinned at the corners of the sample in real space. Furthermore, the CrSiTe3 monolayer retains SOTI features when the spin–orbit coupling (SOC) is considered, as evidenced by the corner charge and corner states distribution. Finally, by applying biaxial strain and hole doping, this study transforms the magnetic insulating bulk states into spin‐gapless semiconducting and half‐metallic bulk states, respectively. Importantly, the topological corner states persist in the spin‐up channel under these conditions. [ABSTRACT FROM AUTHOR]

Background. Immunotherapy represented by PD-1 blockades had become the standard of care for advanced non-small cell lung cancer (NSCLC) gradually. Unfortunately, several PD-1 inhibitor-related studies excluded elderly patients with NSCLC over 75 years of age, resulting in relatively limited evidence regarding the efficacy and safety of PD-1 in elderly patients with NSCLC clinically. Objective. This study aimed to identify the effectiveness and safety of PD-1 blockade monotherapy among elderly patients with advanced NSCLC. Methods. Elderly patients with advanced NSCLC (≥65 years) who received PD-1 blockade monotherapy from September 2018 to December 2021 were screened retrospectively, and a total of 68 elderly patients with NSCLC were eligible for inclusion ultimately. The PD-1 blockades in the study were the available PD-1 monoclonal antibodies that had been approved for marketing in China, including camrelizumab, sintilimab, pembrolizumab, and nivolumab. The effectiveness and safety of the patients was collected retrospectively. Additionally, the correlation between prognosis and baseline characteristic subgroups was analyzed to identify the potential risk factors for progression-free survival (PFS). Results. The median age of the 68 elderly patients with advanced NSCLC was 73 years (range: 65–82 years). Best overall response during PD-1 blockade administration suggested that no patients were found with complete response, partial response was found in 14 patients, stable disease was noted in 29 patients, and 25 patients had progressive disease, yielding an objective response rate (ORR) of 20.6% (95%CI: 11.7%–32.1%) and a disease control rate (DCR) of 63.2% (95%CI: 50.7%–74.6%). Furthermore, prognostic analysis exhibited that the median progression-free survival (PFS) of the 68 patients with advanced NSCLC was 3.5 months (95%CI: 2.4–4.6) and the median overall survival (OS) was 10.5 months (95%CI: 6.3–14.7). Additionally, a total of 48 patients were observed with the treatment-related adverse reaction (70.6%) of the 68 elderly patients with NSCLC, and the incidence of grade 3 or above adverse reactions was 16.2%. Specifically, the most common adverse reactions were fatigue, diarrhea, rash, and abnormal liver function with the incidence of 25.0%, 22.1%, 16.2%, and 14.7%, respectively. Exploratory analysis between PFS and baseline characteristic subgroups suggested that ECOG performance status and number of metastatic lesions might be independent factors for PFS. Conclusion. PD-1 blockade monotherapy exhibited potential effectiveness and acceptable toxicity for elderly patients with NSCLC. ECOG performance status and number of metastatic lesions might be potential risk factors to predict the PFS of elderly patients with advanced NSCLC. [ABSTRACT FROM AUTHOR]

The most common methods of predicting a gas/water two-phase relative permeability include experimental measurement, theoretical simulation, and numerical calculation. The experimental method is relatively accurate but time-consuming and laborious. The method of theoretical modeling involves a complicated solving process, and the range of application of the numerical calculation method is comparatively narrow. In this work, based on the least square support vector machine (LSSVM) combined with the gray optimization algorithm (GWO), the prediction model (GWO-LSSVM) of the gas/water phase permeability is established. The model was validated by the gas-water two-phase relative permeability data obtained by a non-steady-state method from a gas reservoir under high pressure/high temperature (133–152.5°C, 50.3–55 MPa) conditions. The irreducible water saturation (Swc), absolute permeability (K), porosity (j), and gas saturation (Sg) have been set as the input parameters. The water phase relative permeability (Krw) and the gas phase relative permeability (Krg) have been set as output variables. The training data of water phase and gas phase relative permeability were 147 and 141, respectively. The prediction data were 32 and 58, respectively. The results show that the absolute relative deviation (AARD) of Krw for the presented GWO-LSSVM model is 3.69%, while that of Krg is 2.92%, showing that the model can accurately predict the gas-water relative permeability at high temperature and high pressure. The method provides a new and effective instrument for estimating the gaswater two-phase relative permeability parameters in the development of gas reservoirs. [ABSTRACT FROM AUTHOR]

When a spherical droplet moves parallel to the direction of motion of its surrounding gas medium, it will deform into an ellipsoidal droplet. In this paper, an exposition of a novel model for predicting the minimum flow rate for the continuous removal of liquids from gas wells based on two theories is presented. First, droplet breakup principle is utilized to microscopically obtain the maximum size parameters of ellipsoidal droplets, and second, droplet force equilibrium is adopted to macroscopically calculate the critical droplet entrainment rate. Moreover, effect of variations in the windward area (attributed to droplet deformation) on the drag coefficient is determined. Impacts of variations in pressure, temperature, and pipe diameter on the gas‐liquid two‐phase friction resistance and gas‐liquid surface tension are also considered. For model verification and comparison with other droplet entrainment models, field data from 3436 gas wells are utilized. The field data well validates the results with a 92% accuracy, indicating that the new model has a better comprehensive performance in determining whether or not a gas well is loaded. Besides, parameter sensitivity analyses including the effects of drag coefficient, surface tension, and friction coefficient on the minimum flow rate of gas are performed. Finally, the relationship curve of critical droplet entrainment rates corresponding to different pressures and pipe diameters is established. [ABSTRACT FROM AUTHOR]

Growing evidence has underscored long non-coding RNAs (lncRNAs) serving as potential biomarkers for cancer prognosis. However, systematic tracking of a lncRNA signature for prognosis prediction in non-small cell lung cancer (NSCLC) has not been accomplished yet. Here, comprehensive analysis with differential gene expression analysis, univariate and multivariate Cox regression analysis based on The Cancer Genome Atlas (TCGA) database was performed to identify the lncRNA signature for prediction of the overall survival of NSCLC patients. A risk-score model based on a 14-lncRNA signature was identified, which could classify patients into high-risk and low-risk groups and show poor and improved outcomes, respectively. The receiver operating characteristic (ROC) curve revealed that the risk-score model has good performance with high AUC value. Multivariate Cox's regression model and stratified analysis indicated that the risk-score was independent of other clinicopathological prognostic factors. Furthermore, the risk-score model was competent for the prediction of metastasis-free survival in NSCLC patients. Moreover, the risk-score model was applicable for prediction of the overall survival in the other 30 caner types of TCGA. Our study highlighted the significant implications of lncRNAs as prognostic predictors in NSCLC. We hope the lncRNA signature could contribute to personalized therapy decisions in the future. [ABSTRACT FROM AUTHOR]

Performing stress‐sensitivity evaluation on a high‐temperature and high‐pressure gas reservoir is essential for correctly understanding the characteristics of physical property changes and reasonably designing the development scheme of a reservoir under stratum conditions. By focusing on six core samples with different physical properties in a gas field in the Yingqiong Basin, stress‐sensitivity experiments have been conducted along with mercury intrusion porosimetry and X‐ray diffraction measurements to study the relationship among porosity, permeability, and effective stress at a temperature of 140°C and effective stress ranging from 2 MPa to 70 MPa. Our results showed that the stress‐sensitivity curve characterized by three‐stage segmentation is primarily affected by average pore radius and mineral composition but has no direct relation with porosity and permeability. Meanwhile, the stress sensitivity of permeability is mainly related to the average pore throat radius and mineral composition of core specimen. The smaller the pore throat radius and the higher the clay content, the stronger the stress sensitivity of permeability. Under high‐temperature and high‐pressure conditions, the stress sensitivities of permeability and porosity can be characterized by power functions although the stress sensitivity of permeability is about 2–11 times higher than that of porosity. [ABSTRACT FROM AUTHOR]

Coronary artery calcification (CAC) is a well-established independent predictor of coronary heart disease, and patients with schizophrenia have significantly higher rates compared to the general population. We performed this study to examine the population-specific risk factors associated with CAC in patients with schizophrenia. In this cross-sectional study, patients with schizophrenia who underwent low-dose chest CT scans between January 2020 and December 2021 were analyzed. Ordinary CAC scores and results of routine blood tests were obtained. Logistic regression was used to calculate the odds ratio (OR) for potential risk factors in patients with and without CAC, while the negative binomial additive model was used to explore the dose-response relationship between risk factors and CAC score. Of the 916 patients, 233 (25.4 %) had CAC, while 683 (74.6 %) did not. After adjusting for confounding factors, higher triglyceride levels (OR = 1.20, 95 % confidence interval (CI): 1.04 to 1.38, p = 0.013) and low triiodothyronine levels (OR = 0.50, 95 % CI: 0.29 to 0.84; p = 0.010) were identified as risk factors for CAC. Both triglycerides (p = 0.021) and triiodothyronine (p = 0.010) were also found to have significant dose-response relationships with CAC scores according to the negative binomial additive model in the exploratory analysis. This study highlights elevated serum triglycerides and decreased triiodothyronine levels as population-specific risk factors for CAC in patients with schizophrenia, suggest the need for close monitoring of CAC in patients with schizophrenia and further prospective trials to provide additional evidence on this topic. • Study examined population-specific risk factors for coronary artery calcification (CAC) in schizophrenia patients. • 25.4 % of 916 patients had CAC. • Elevated triglyceride (OR = 1.20) and low triiodothyronine (OR = 0.50) identified as population-specific risk factors for CAC. • Significant dose-response relationships between triglycerides and triiodothyronine with CAC score found. • Study highlights need for close monitoring of patients and further research to provide evidence on topic. [ABSTRACT FROM AUTHOR]

Abstract Some thermodynamic and physicochemical properties of N -alkyl-pyridinium bis((trifluoromethyl)sulfonyl)imide ([C n PY][NTF 2 ], n = 4, 6, 8) ionic liquids (ILs) were investigated through inverse gas chromatography at temperatures from 333.15 K to 373.15 K. A total of 23 solvents were used to compute the specific retention volume and Flory–Huggins interaction parameters. The Hildebrand solubility parameters of three ILs were calculated based on the solubility parameters of probe solvents. In addition, the enthalpy values of vaporization of the ILs were obtained based on the Hildebrand solubility parameters. Graphical abstract Image 1 Highlights • IGC was developed to characterize [C n PY][NTF 2 ] (n = 4,6,8) by using twenty-three solvents. • Flory-Huggins interaction parameters of [C n PY][NTF 2 ] (n = 4,6,8) were determined by IGC. • Hildebrand solubility parameters and enthalpies of vaporization of [C n PY][NTF 2 ] (n = 4,6,8) were determined. [ABSTRACT FROM AUTHOR]

Highlights • A one-step, quantitative method for CMNV was developed. • The assay had a detection limit of 5.7 viral copies. • The assay was no cross-reactivity observed with six common shrimp viruses. • This is a useful tool for CMNV detection and quantification. Abstract Covert mortality nodavirus (CMNV), an emerging RNA virus, is the pathogen of viral covert mortality disease (VCMD), which has emerged as a cause of serious losses in shrimp aquaculture in China. To improve VCMD diagnosis, a one-step, real-time TaqMan probe-based reverse transcription quantitative PCR (RT-qPCR) was developed in this study. The TaqMan RT-qPCR was optimized firstly, whereby the best results were obtained with 0.2 μM of each primer, 0.2 μM probe, and 0.5 μL Enzyme Mix II. The optimal reaction program was determined as 15 min at 51ºC for reverse transcription and 5 min at 95 ºC, followed by 40 cycles of denaturation at 94 ºC for 10 s, and annealing and extension at 52.7 ºC for 30 s. The optimized assay detected as little as 9.6 pg total RNA from CMNV-infected shrimp and 5.7 copies of the target plasmid. The RT-qPCR assay for CMNV with a high correlation coefficient (r2 = 0.996) was developed basing on the standard curve generated by plotting the threshold cycle values (y) against the common logarithmic copies (log 10 n c as x; n c is copy number) of pMD20-CMNV. The diagnostic sensitivity and specificity of this assay versus the previously reported RT-qPCR was 96.2% and 98.0%, respectively. This method is highly specific to CMNV, as it showed no cross-reactivity with other common shrimp viruses. It is anticipated that the newly developed and optimized RT-qPCR assay will be instrumental for the rapid diagnosis and quantitation of CMNV. [ABSTRACT FROM AUTHOR]

A convenient form of the generalized Trotter formula for path-integral simulations has been investigated for various systems and proves to be much better than the primitive. The hydrogen atom, which is pathological for the primitive algorithm, is solved by the new method but the results are not completely satisfactory. [ABSTRACT FROM AUTHOR]

A method is devised to obtain an 1=0 pseudopotential for the electron–argon system using the local density functional approximation. The quality of the potential is checked against low-energy scattering data and is found to be good. The method should generalize quite simply to other inert gas–electron and to closed-shell ion–electron systems. [ABSTRACT FROM AUTHOR]

Background Genome-wide association study (GWAS) studies have showed that single nucleotide polymorphisms (SNPs) in OCA2 gene were associated with the survival of breast cancer patients treated with adjuvant chemotherapy. To further explain the association between OCA2 SNPs and breast cancer survival, we investigated the predictive value of rs4778137 located in OCA2 in local advanced breast cancer patients receiving neoadjuvant chemotherapy. Patients and methods A case-cohort with 150 breast cancer patients was performed to evaluate the effects of the OCA2 rs4778137 on breast cancer survival. The association between rs4778137 genotypes and pathological complete response (pCR, defined that the postoperative pathology indicating no residual invasive breast cancer in the breast or the axillary lymph node) were analyzed. Logistic regression analysis was performed to identify the independent predictors of pCR. Survival was assessed by Kaplan-Meier method and Cox regression analysis according to the rs4778137 genotypes. Results The differences between pCR and the rs4778137 genotypes were statistically significant ( p  < 0.05). The patients with genotype GG harbored a better disease-free survival (HR: 2.358, p  = 0.000) and overall survival (HR: 1.578, p  = 0.008) than the patients with genotype CC in rs4778137. The further Univariate and Multivariate survival analysis revealed that SNP rs4778137 was an independent predictive factor of disease-free survival ( p  = 0.000/ p  = 0.001) and overall survival ( p  = 0.006/ p  = 0.045). Conclusion The OCA2 rs4778137 may be a predictor for the clinical response and survival in local advanced breast cancer patients who received neoadjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the jump spillover effects between oil prices and exchange rates. To identify the latent historical jumps for exchange rates and oil prices, we use a Bayesian MCMC approach to estimate the stochastic volatility model with correlated jumps in both returns and volatilities for each. We examine the simultaneous jump intensities and the conditional jump spillover probabilities between oil prices and exchange rates, finding strong evidence of jump spillover effects. Further analysis shows that the jump spillovers are mainly due to exogenous events such as financial crises and geopolitical events. Thus, the findings have important implications for financial risk management. [ABSTRACT FROM AUTHOR]

Interest in tight gas reservoirs (TGR) has quickly spread worldwide. Most researches on the permeability stress-sensitivity of tight gas reservoirs mainly concentrated on experimental approach, physical modeling or pressure behavior analysis, while transient production rate performance does not attract much attention. This study developed a dual-porosity model of a horizontal well in fractured tight gas reservoirs considering the stress-sensitivity effect. The solution methods include variable substitution, perturbation technique, Laplace transformation, Sturm-Liouville eigenvalue theory, orthogonal transformation and numerical inversion. The results showed that the production rate decreases with the increasing of permeability modulus and the derivative curve will be warped up during the whole system late radial flow stage. The influences of other parameters are also analyzed. The work undertaken here has both theoretical and practical significance in predicting production performance and evaluating underground fluid transport in such formations. [ABSTRACT FROM AUTHOR]

To investigate the effects of genotype and growing environment on avenanthramides and antioxidant activity of oats, the total phenolic content (TPC), avenanthramide compositions, and antioxidant activity were determined for whole oat from 39 cultivars grown in four locations in northwestern China (Inner Mongolia, Qinghai, Shanxi and Gansu). The results demonstrated that environment (E), genotype (G) and the interaction of these factors (E × G) significantly affected TPC, concentration of avenanthramide 2c (2c, ranged from 6.24 to 136.20 mg kg −1 ), avenanthramide 2p (2p, 6.07–112.25 mg kg −1 ), avenanthramide 2f (2f, 7.26–222.77 mg kg −1 ) and antioxidant activity of oats. The effect of E was considerably greater than that of G or E × G. Based on G plus G × E interaction biplots (GGE biplots) analysis, the four locations in northwestern China can be divided into either two or three regions. Qinghai was determined to be distinct from the other locations. Cultivar Bayou 9 and oats grown in Gansu exhibited the highest TPCs, concentrations of 2c, 2p, 2f and antioxidant activity. The results suggest that oats containing more avenanthramides and exhibiting high levels of antioxidant activity could be obtained by selecting an appropriate genotype and growth location. [ABSTRACT FROM AUTHOR]

Ricin is a potent ribotoxin that is considered a bioterror threat due to its ease of isolation and possibility of aerosolization. In yeast, mutation of arginine residues away from the active site results in a ricin toxin A chain (RTA) variant that is unable to bind the ribosome and exhibits reduced cytotoxicity. The goal of the present work was to determine if these residues contribute to ribosome binding and cytotoxicity of RTA in mammalian cells. The RTA mutant R193A/R235A did not interact with mammalian ribosomes, while a G212E variant with a point mutation near its active site bound ribosomes similarly to wild-type (WT) RTA. R193A/R235A retained full catalytic activity on naked RNA but had reduced activity on mammalian ribosomes. To determine the effect of this mutant in intact cells, pre R193A/R235A containing a signal sequence directing it to the endoplasmic reticulum and mature R193A/R235A that directly targeted cytosolic ribosomes were each expressed. Depurination and protein synthesis inhibition were reduced by both pre- and mature R193A/R235A relative to WT. Protein synthesis inhibition was reduced to a greater extent by R193A/R235A than by G212E. Pre R193A/R235A caused a greater reduction in caspase activation and loss of mitochondrial membrane potential than G212E relative to WT RTA. These findings indicate that an RTA variant with reduced ribosome binding is less toxic than a variant with less catalytic activity but normal ribosome binding activity. The toxin-ribosome interaction represents a novel target for the development of therapeutics to prevent or treat ricin intoxication. [ABSTRACT FROM AUTHOR]

X-ray pulse profile is an important physical quantity for X-ray pulsar based navigation (XPNAV). In order to improve the Signal-to-Noise-Ratio (SNR) of pulse profile and reduce computation complexity, this paper proposed an efficient pulse profile construction method based on Compressed Sensing (CS). This method first builds models for standard and integrated pulse profiles. Then, a sensing matrix based on Hadamard matrix is proposed for enhancing the percentage of successful construction. Finally, based on the sparse coefficient vector calculated by the proposed CS method, a pulse profile with high SNR will be obtained. The proposed method is validated using the real data of Crab pulsar observed by Rossi X-ray Timing Explorer (RXTE). Compared with the random 0–1 matrix and random Gaussian matrix, the pulse profile can be completely constructed by using the proposed matrix when the sampling ratio is 0.6, and compared with Epoch Folding method, the proposed CS method can improve the SNR of the pulse profile at least 15.859 dB when the observation time is 1 s and at least 20.33 dB when the observation time is 700 s. The results demonstrate the high performance of the proposed method in constructing pulse profile of high SNR with short-time observation data, which can significantly facilitate the real-time and high precision time-of-arrival (TOA) estimation and the position and velocity measurement in XPNAV. [ABSTRACT FROM AUTHOR]

Isorhamnetin has been reported to have anti-inflammatory, anti-oxidative, and anti-proliferative effects. The aim of this study was to investigate the protective effect of isorhamnetin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice by inhibiting the expression of cyclooxygenase-2 (COX-2). The effects of isorhamnetin on LPS-induced lung pathological damage, wet/dry ratios and the total protein level in bronchoalveolar lavage fluid (BALF), inflammatory cytokine release, myeloperoxidase (MPO) and superoxide dismutase (SOD) activities, and malondialdehyde (MDA) level were examined. In addition, the COX-2 activation in lung tissues was detected by Western blot. Isorhamnetin pretreatment improved the mice survival rates. Moreover, isorhamnetin pretreatment significantly attenuated edema and the pathological changes in the lung and inhibited protein extravasation in BALF. Isorhamnetin also significantly decreased the levels of inflammatory cytokines in BALF. In addition, isorhamnetin markedly prevented LPS-induced oxidative stress. Furthermore, isorhamnetin pretreatment significantly suppressed LPS-induced activation of COX-2. Isorhamnetin has been demonstrated to protect mice from LPS-induced ALI by inhibiting the expression of COX-2. [ABSTRACT FROM AUTHOR]

We report the template-free fabrication of three-dimensional hierarchical nanostructures, i.e. , three-dimensional interconnected magnetic chemically modified graphene oxide (3D-Mag-CMGO), through a simple and low-cost self-assembly process using one-pot reaction based on solvothermal method. The excellent properties of the 3D-Mag-CMGO are characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), FTIR, elementary analyzer (EA) and X-ray photoelectron spectroscopy (XPS). The easiness-to-handle of the magnetic dispersive solid phase extraction (Mag-dSPE) procedure is developed for preconcentration of 21 allergenic disperse dyes from river water. The obtained results show the higher extraction capacity of 3D-Mag-CMGO with recoveries between 80.0–112.0%. Furthermore, an ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC–MS/MS) method for determination of 21 allergenic disperse dyes in river at sub-ppt levels has been developed with pretreatment of the samples by Mag-dSPE. The limits of quantification (LOQs) for the allergenic disperse dyes are between 0.57–34.05 ng/L. Validation results on linearity, specificity, trueness and precision, as well as on application to the analysis of 21 allergenic disperse dyes in fifty real samples demonstrate the applicability to environment monitoring analysis. [ABSTRACT FROM AUTHOR]

The low intensity of the X-ray pulsar signal and the strong X-ray background radiation lead to low signal-to-noise ratio (SNR) of the X-ray pulsar observed profile obtained through epoch folding, especially when the observation time is not long enough. This signifies the necessity of denoising of the observed profile. In this paper, the statistical characteristics of the X-ray pulsar signal are studied, and a signal-dependent noise model is established for the observed profile. Based on this, a profile noise reduction method by performing a local linear minimum mean square error filtering in the un-decimated wavelet domain is developed. The detail wavelet coefficients are rescaled by multiplying their amplitudes by a locally adaptive factor, which is the local variance ratio of the noiseless coefficients to the noisy ones. All the nonstationary statistics needed in the algorithm are calculated from the observed profile, without a priori information. The results of experiments, carried out on simulated data obtained by the ground-based simulation system and real data obtained by Rossi X-Ray Timing Explorer satellite, indicate that the proposed method is excellent in both noise suppression and preservation of peak sharpness, and it also clearly outperforms four widely accepted and used wavelet denoising methods, in terms of SNR, Pearson correlation coefficient and root mean square error. [ABSTRACT FROM AUTHOR]

An experimental study was conducted to identify treatment conditions for sterilizing naked oats while retaining inherent enzyme activity. Naked oats were processed with superheated steam (SS) with variations in processing times (1-5 min) and temperature (140-200C). The number of bacteria and molds were significantly decreased as the SS temperature and exposure time increased. After naked oats were treated with SS at 160-170C for 2 min, the number of microbes were reduced below the safe storage limit. The SS treatment effectively reduced populations of bacteria and mold and had a less pronounced effect on enzymatic activity. This method shows great potential for usage as a sterilization treatment in the food processing industry. [ABSTRACT FROM AUTHOR]

Flow in porous media under stress is very important in various scientific and engineering fields. It has been shown that stress plays an important role in effect of permeability and porosity of porous media. In this work, novel predictive models for permeability and porosity of porous media considering stress sensitivity are developed based on the fractal theory and mechanics of materials. Every parameter in the proposed models has clear physical meaning. The proposed models are evaluated using previously published data for permeability and porosity measured in various natural materials. The predictions of permeability and porosity show good agreement with those obtained by the available experimental data and illustrate that the proposed models can be used to characterize the flow in porous media under stress accurately. [ABSTRACT FROM AUTHOR]

Horizontal well (HW) was divided into several elements after acidizing. In each element, there would exist a composite zone that was made up of damage zone (DZ) and acidizing zone (AZ). Local skin factor after acidizing was used to describe the resistance in each composite zone. The models for local skin factor and productivity of HW were created using the method of equivalent filtration resistance and displacement between two similar flow modes. According to the solution of the models, type curves of skin factor and production-increasing ratio after acidizing were illustrated, and the effect of different parameters in DZ and AZ on distribution of skin factor and production-increasing ratio after acidizing were discussed. The present model has a significant guide on the practice of acidizing technology. [ABSTRACT FROM AUTHOR]

After multistage fracturing, the flowback of fracturing fluid will cause two-phase flow through hydraulic fractures in shale gas reservoirs. With the consideration of two-phase flow and desorbed gas transient diffusion in shale gas reservoirs, a two-phase transient flow model of multistage fractured horizontal well in shale gas reservoirs was created. Accurate solution to this flow model is obtained by the use of source function theory, Laplace transform, three-dimensional eigenvalue method, and orthogonal transformation. According to the model’s solution, the bilogarithmic type curves of the two-phase model are illustrated, and the production decline performance under the effects of hydraulic fractures and shale gas reservoir properties are discussed. The result obtained in this paper has important significance to understand pressure response characteristics and production decline law of two-phase flow in shale gas reservoirs. Moreover, it provides the theoretical basis for exploiting this reservoir efficiently. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical model on the payback period of a subcritical ORC (organic Rankine cycle) system for recovering low-grade waste heat of flue gas. Based on the minimum payback period principle, a detailed internal parameter optimization is carried out. Furthermore, the influences of external parameters on the payback period are analyzed and a new criterion of screening working fluids is proposed. Results show that the payback period of the ORC system decreases before increasing with the increase of evaporation temperature, condensation temperature, and the pinch point temperature differences in the evaporator and condenser. The minimum payback period of the ORC system decreases monotonously with the increase of the inlet temperature, mass flow rate of the flue gas, and the electricity price. When the minimum payback period and the net power output are used as indicators of selecting working fluids of the ORC system, this work identifies a specific working fluid for a given inlet flue gas temperature. We demonstrate this process by showing that R236a, R245fa, and R113 should be selected as the working fluids when the inlet temperatures of the flue gas are around 150 °C, 200 °C and 250 °C, respectively. [ABSTRACT FROM AUTHOR]

As the most common form of dementia and a progressive neurodegenerative disorder, Alzheimer's disease (AD) affects over 10% world population with age 65 and older. The disease is neuropathologically associated with progressive loss of neurons and synapses in specific brain regions, deposition of amyloid plaques and neurofibrillary tangles, neuroinflammation, blood–brain barrier (BBB) breakdown, mitochondrial dysfunction, and oxidative stress. Despite the intensive effort, there is still no cure for the disorder. Stem cell-derived exosomes hold great promise in treating various diseases, including AD, as they contain a variety of anti-apoptotic, anti-inflammatory, and antioxidant components. Moreover, stem cell-derived exosomes also promote neurogenesis and angiogenesis and can repair damaged BBB. In this review, we will first outline the major neuropathological features associated with AD; subsequently, a discussion of stem cells, stem cell-secreted exosomes, and the major exosome isolation methods will follow. We will then summarize the recent data involving the use of mesenchymal stem cell- or neural stem cell-derived exosomes in treating AD. Finally, we will briefly discuss the challenges, perspectives, and clinical trials using stem cell-derived exosomes for AD therapy. [ABSTRACT FROM AUTHOR]

A model for transient flow in porous media embedded with randomly distributed tree-shaped fractal networks was presented based on the fractal properties of tree-shaped capillaries and generalized Darcy's law. The dimensionless expression of flowing pressure was developed using the Laplace transform and Stehfest numerical inversion method. The bilogarithmic type curves were illustrated and the influences of different fractal factors on dimensionless flowing pressure were also discussed. The presented study indicated that the fractal characteristics for the tree-shaped fractal networks should be considered in analysis of transient flow in the heterogeneous porous media. The proposed model may be conducible to a better understanding of the mechanism for transient flow in the multi-porosity porous media. [ABSTRACT FROM AUTHOR]

A permeability model for porous media considering the stress sensitivity is derived based on mechanics of materials and the fractal characteristics of solid cluster size distribution. The permeability of porous media considering the stress sensitivity is related to solid cluster fractal dimension, solid cluster fractal tortuosity dimension, solid cluster minimum diameter and solid cluster maximum diameter, Young's modulus, Poisson's ratio, as well as power index. Every parameter has clear physical meaning without the use of empirical constants. The model predictions of permeability show good agreement with those obtained by the available experimental expression. The proposed model may be conducible to a better understanding of the mechanism for flow in elastic porous media. [ABSTRACT FROM AUTHOR]

A transient flow model for power-law fluid in fractal porous media is derived by combining transient flow theory with the fractal properties of tortuous capillaries. Pressure changes of transient flow for power-law fluid in fractal porous media are related to pore fractal dimension, tortuosity fractal dimension and the power-law index. Additionally, the starting pressure gradient model of power-law fluid in fractal porous media is established. Good agreement between the predictions of the present model and that of the traditional empirical model is obtained, the sensitive parameters that influence the starting pressure gradient are specified and their effects on the starting pressure gradient are discussed. [ABSTRACT FROM AUTHOR]

Ricin A chain (RTA) undergoes retrograde trafficking and is postulated to use components of the endoplasmic reticulum (ER) associated degradation (ERAD) pathway to enter the cytosol to depurinate ribosomes. However, it is not known how RTA evades degradation by the proteasome after entry into the cytosol. We observed two distinct trafficking patterns among the precursor forms of wild type RTA and nontoxic variants tagged with enhanced green fluorescent protein (EGFP) at their C-termini in yeast. One group, which included wild type RTA, underwent ER-to-vacuole transport, while another group, which included the G83D variant, formed aggregates in the ER and was not transported to the vacuole. Peptide: N-glycanase (Png1), which catalyzes degradation of unfolded glycoproteins in the ERAD pathway affected depurination activity and toxicity of wild type RTA and G83D variant differently. PreG83D variant was deglycosylated by Png1 on the ER membrane, which reduced its depurination activity and toxicity by promoting its degradation. In contrast, wild type preRTA was deglycosylated by the free pool of Png1 in the cytosol, which increased its depurination activity, possibly by preventing its degradation. These results indicate that wild type RTA has a distinct requirement for Png1 compared to the G83D variant and is deglycosylated by Png1 in the cytosol as a possible strategy to avoid degradation by the ERAD pathway to reach the ribosome. [ABSTRACT FROM AUTHOR]

The public's stated value and heterogeneous preferences are crucial for formulating policies and financing approaches to promote the control of agricultural non-point-source pollution (ANSP). This study aims to investigate urban residents' willingness to pay (WTP) for ANSP control and analyse the source of preference heterogeneity using a choice experiment method. Survey data were obtained from face-to-face interviews with 595 respondents in south Shaanxi Province, China. We found that respondents' average WTP for the attributes of ANSP control schemes were 2.34 yuan ($0.36) and 5.42 yuan ($0.83) per year per household for a 1% reduction in fertiliser and pesticide use, respectively. We also found significant impacts of WTP from individuals' socio-economic characteristics (i.e., gender, age, education, and income) and cognitive factors (i.e., policy understanding, and government trust). Thus, to improve the efficiency and universality of ANSP control policy, the public's willingness and preference heterogeneity should be thoroughly taken into policy formulation. [Display omitted] • Most urban residents are willing to pay a certain fee for ANSP control. • Public's marginal willingness to pay for the reduction of fertiliser and pesticide 2.34 yuan ($0.36) and 5.42 yuan ($0.83) per year per household for a 1% reduction in fertiliser and pesticide use, respectively. • Reference heterogeneity of urban residents' WTP exists and comes from individuals' socio-economic characteristics and cognitive factors. • When collecting ecological compensation funds from the public, policymakers should fully consider these heterogeneous preferences to formulate adaptive policy and management approaches. [ABSTRACT FROM AUTHOR]

The total synthesis of Hirtellanine A was accomplished by two different synthetic approaches. Hirtellanine A was assembled using a one-pot, tandem acid-mediated deprotection and tautomerization cascade starting from quinone derivative 23. The key features of the synthesis include a Houben-Hoesch reaction of aryl cyanide 3 with phloroglucinol, a one-pot sequential boronation, a Suzuki-Miyaura cross-coupling of aryl bromide 33 with aryl iodide 26, and a base-mediated regioselective Claisen rearrangement for the benzopyran construction. [ABSTRACT FROM AUTHOR]

Ricin A chain ( RTA) depurinates the α-sarcin/ricin loop after it undergoes retrograde trafficking to the cytosol. The structural features of RTA involved in intracellular transport are not known. To explore this, we fused enhanced green fluorescent protein ( EGFP) to precursor ( preRTA-EGFP), containing a 35-residue leader, and mature RTA ( matRTA-EGFP). Both were enzymatically active and toxic in Saccharomyces cerevisiae. PreRTA-EGFP was localized in the endoplasmic reticulum ( ER) initially and was subsequently transported to the vacuole, whereas matRTA-EGFP remained in the cytosol, indicating that ER localization is a prerequisite for vacuole transport. When the two glycosylation sites in RTA were mutated, the mature form was fully active and toxic, suggesting that the mutations do not affect catalytic activity. However, nonglycosylated preRTA-EGFP had reduced toxicity, depurination and delayed vacuole transport, indicating that N-glycosylation affects transport of RTA out of the ER. Point mutations in the C-terminal hydrophobic region restricted RTA to the ER and eliminated toxicity and depurination, indicating that this sequence is critical for ER exit. These results demonstrate that N-glycosylation and the C-terminal hydrophobic region stimulate the toxicity of RTA by promoting ER export. The timing of depurination coincided with the timing of vacuole transport, suggesting that RTA may enter the cytosol during vacuole transport. [ABSTRACT FROM AUTHOR]

Ricin A-chain ( RTA) depurinates the sarcin-ricin loop of 28S ribosomal RNA and inhibits protein synthesis in mammalian cells. In yeast, the ribosomal stalk facilitates the interaction of RTA with the ribosome and subsequent depurination. Despite homology between the stalk structures from yeast and humans, there are notable differences. The human ribosomal stalk contains two identical heterodimers of P1 and P2 bound to P0, whereas the yeast stalk consists of two different heterodimers, P1α- P2β and P2α- P1β, bound to P0. RTA exhibits higher activity towards mammalian ribosomes than towards ribosomes from other organisms, suggesting that the mode of interaction with ribosomes may vary. Here, we examined whether the human ribosomal stalk proteins facilitate the interaction of RTA with human ribosomes and subsequent depurination of the sarcin-ricin loop. Using small interfering RNA-mediated knockdown of P1/ P2 expression in human cells, we demonstrated that the depurination activity of RTA is lower when P1 and P2 levels are reduced. Biacore analysis showed that ribosomes from P1/ P2-depleted cells have a reduced ability to bind RTA, which correlates with reduced depurination activity both in vitro and inside cells. RTA interacts directly with recombinant human P1- P2 dimer, further demonstrating the importance of human P1 and P2 in enabling RTA to bind and depurinate human ribosomes. Structured digital abstract P2, P1 and RTA physically interact by surface plasmon resonance (View interaction), P2, P1 and RTA physically interact by anti bait coimmunoprecipitation (View interaction) [ABSTRACT FROM AUTHOR]

Utilization of faeces has long been a popular approach for genetic and ecological studies of wildlife. However, the success of molecular marker genotyping and genome resequencing is often unpredictable due to insufficient enrichment of endogenous DNA in the total faecal DNA that is dominated by bacterial DNA. Here, we report a simple and cheap method named PEERS to predominantly lyse animal cells over bacteria by using sodium dodecyl sulphate so as to discharge endogenous DNA into liquid phase before bacterial DNA. By brief centrifugation, total DNA with enriched endogenous fraction can be extracted from the supernatant using routine methods. Our assessments showed that the endogenous DNA extracted by PEERS was significantly enriched for various types of faeces from different species, preservation time and conditions. It significantly improves the genotyping correctness and efficiency of genome resequencing with the total additional cost of $ 0.1 and a short incubation step to treat a faecal sample. We also provide methods to assess the enrichment efficiency of mitochondrial and nuclear DNA and models to predict the usability of faecal DNA for genotyping of short tandem repeat, single‐nucleotide polymorphism and whole‐genome resequencing. [ABSTRACT FROM AUTHOR]

Voltage-gated potassium (Kv) channels are tetrameric assemblies of transmembrane Kv proteins with cytosolic N- and C-termini. The N-terminal domain of Kv1 proteins binds to β-subunits, but the role of the C-terminus is less clear. Therefore, we studied the role of the C-terminus in regulating Kv1.5 channel and its interactions with Kvβ-subunits. When expressed in COS-7 cells, deletion of the C-terminal domain of Kv1.5 did not affect channel gating or kinetics. Coexpression of Kv1.5 with Kvβ3 increased current inactivation, whereas Kvβ2 caused a hyperpolarizing shift in the voltage dependence of current activation. Inclusion of NADPH in the patch pipette solution accelerated the inactivation of Kv1.5-Kvβ3 currents. In contrast, NADP decreased the rate and the extent of Kvβ3-induced inactivation and reversed the hyperpolarizing shift in the voltage dependence of activation induced by Kvβ2. Currents generated by Kv1.5ΔC+Kvβ3 or Kv1.5ΔC+Kvβ2 complexes did not respond to changes in intracellular pyridine nucleotide concentration, indicating that the C-terminus is required for pyridine nucleotide-dependent interactions between Kvβ and Kv1.5. A glutathione- S-transferase (GST) fusion protein containing the C-terminal peptide of Kv1.5 did not bind to apoKvβ2, but displayed higher affinity for Kvβ2:NADPH than Kvβ2:NADP. The GST fusion protein also precipitated Kvβ proteins from mouse brain lysates. Pull-down experiments, structural analysis and electrophysiological data indicated that a specific region of the C-terminus (Arg543-Val583) is required for Kvβ binding. These results suggest that the C-terminal domain of Kv1.5 interacts with β-subunits and that this interaction is essential for the differential regulation of Kv currents by oxidized and reduced nucleotides. [ABSTRACT FROM AUTHOR]

The relativistic problem of spinless particles with position-dependent mass subject to kink-like potentials (~tanh αx) is investigated. By using the basic concepts of the supersymmetric quantum mechanics formalism and the functional analysis method, we solve exactly the position-dependent effective mass Klein-Gordon equation with the vector and scalar kink-like potential coupling, and obtain the bound state solutions in the closed form. It is found that in the presence of position-dependent mass there exists the symmetry that the discrete positive energy spectra and negative energy spectra are symmetric about zero energy for the case of a mixed vector and scalar kink-like potential coupling, and in the presence of constant mass this symmetry only appears for the cases of a pure scalar kink-like potential coupling or massless particles. [ABSTRACT FROM AUTHOR]

Abstract: Shiga toxins produced by Escherichia coli O157:H7 are responsible for food poisoning and hemolytic uremic syndrome (HUS). The A subunits of Shiga toxins (Stx1A and Stx2A) inhibit translation by depurinating a specific adenine in the large rRNA. To determine if Stx1A and Stx2A require the ribosomal stalk for depurination, their activity and cytotoxicity were examined in the yeast P protein deletion mutants. Stx1A and Stx2A were less toxic and depurinated ribosomes less in a strain lacking P1/P2 on the ribosome and in the cytosol (ΔP2) than in a strain lacking P1/P2 on the ribosome, but containing free P2 in the cytosol (ΔP1). To determine if cytoplasmic P proteins facilitated depurination, Stx1A and Stx2A were expressed in the P0ΔAB mutant, in which the binding sites for P1/P2 were deleted on the ribosome, and P1/P2 accumulated in the cytosol. Stx1A was less toxic and depurinated ribosomes less in P0ΔAB, suggesting that intact binding sites for P1/P2 were critical. In contrast, Stx2A was toxic and depurinated ribosomes in P0ΔAB as in wild type, suggesting that it did not require the P1/P2 binding sites. Depurination of ΔP1, but not P0ΔAB ribosomes increased upon addition of purified P1α/P2βin vitro, and the increase was greater for Stx1 than for Stx2. We conclude that cytoplasmic P proteins stimulate depurination by Stx1 by facilitating the access of the toxin to the ribosome. Although ribosomal stalk is important for Stx1 and Stx2 to depurinate the ribosome, Stx2 is less dependent on the stalk proteins for activity than Stx1 and can depurinate ribosomes with an incomplete stalk better than Stx1. [Copyright &y& Elsevier]

By using a new improved approximation scheme to deal with the centrifugal term, we solve approximately the Schrödinger equation with the generalized Morse potentials for the arbitrary angular momentum values. The bound state energy spectra and the unnormalized radial wave functions have been approximately obtained by using the basic concept of the supersymmetric shape invariance formalism and the function analysis method. The numerical experiments show that our approximate results are in better agreement with those obtained by using the numerical integration approach than the approximate results obtained by using the conventional approximation scheme to deal with the centrifugal term. We also calculate the rotational transition frequencies for HF molecule and compare them with the experimental data. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

Abstract: The Aldo Keto Reductases (AKRs) are a superfamily of enzymes that catalyze the reduction of biogenic and xenobiotic aldehydes and ketones. AKR1B family has 2 known members in humans and 3 in rodents. Two novel gene loci, hereafter referred to as AKR1B15 in human and Akr1b16 in mouse have been predicted to exist within the AKR1B clusters. AKR1B15 displays 91% and 67% sequence identity with human genes AKR1B10 and AKR1B1, respectively while Akr1b16 shares 82–84% identity with murine Akr1b8 and Akr1b7. We tested the hypothesis that AKR1B15 and Akr1b16 genes are expressed as functional proteins in human and murine tissues, respectively. Using whole tissue mRNA, we were able to clone the full-length open reading frames for AKR1B15 from human eye and testes, and Akr1b16 from murine spleen, demonstrating that these genes are transcriptionally active. The corresponding cDNAs were cloned into pET28a and pIRES-hrGFP-1α vectors for bacterial and mammalian expression, respectively. Both genes were expressed as 36kDa proteins found in the insoluble fraction of bacterial cell lysate. These proteins, expressed in bacteria showed no enzymatic activity. However, lysates from COS-7 cells transfected with AKR1B15 showed a 4.8-fold (with p-nitrobenzaldehyde) and 3.3-fold (with dl-glyceraldehyde) increase in enzyme activity compared with untransfected COS-7 cells. The Akr1b16 transcript was shown to be ubiquitously expressed in murine tissues. Highest levels of transcript were found in heart, spleen, and lung. From these observations we conclude that the predicted AKR1B15 and 1b16 genes are expressed in several murine and human tissues. Further studies are required to elucidate their physiological roles. [Copyright &y& Elsevier]

Abstract: A lithium-organic coordination compound based on an aromatic carbonyl derivative, [Li2(C14H6O4)], was synthesized by the dehydration of [Li2(C14H6O4)·H2O], and used as a novel lithium-inserted material for lithium ion batteries. The synthesized material has initial discharge capacity of 126 and 115mAh/g at current densities of 22 and 111mAh/g, corresponding to the columbic efficiency of 99.2% and 98.3% at the first cycle, and its capacity fading is only 5% and 13% after 50 cycles, respectively, showing that this compound is a promising candidate as lithium-inserted material for lithium ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Background: There are numerous reports of abnormalities in the expression of the sodium- and potassium-activated adenosine triphosphatase (Na,K-ATPase) in response to an ionic stress with ethacrynic acid (ECA) challenge in bipolar subjects. However, all of these studies have been in out-bred populations. In an attempt to reduce the genetic variability associated with this observation, we examined this phenomenon within an isolated breeding population. Methods: We studied 36 lymphoblastoid cell lines obtained from Old Order Amish individuals who had bipolar disorder, type I (16), or were unaffected siblings of the same gender (9) or unrelated normal controls(11). Cells were treated with10− 5 M ECA for 3days after which Na,K-ATPase alpha1 protein expression and activity ([3H]-ouabain binding, 86Rb-uptake, and intracellular sodium and potassium concentrations) were measured. Results: Cells from bipolar patients expressed less Na,K-ATPase as measured by immunoblot analysis after ECA treatment (0.94±SD 0.13 relative units) compared to unaffected siblings (1.06±0.12, P =0.029) and Old Order Amish normal controls (1.06±0.14, P =0.0004). None of the other variables studied were different. Limitations: This is a study of peripheral cells which do not express all of the Na,K-ATPase expressed in the brain. The observed difference is small. Conclusions: Ethacrynic-acid-stimulated lymphoblast sodium pump expression in Old Order Amish bipolar subjects is reduced compared to Amish controls. [Copyright &y& Elsevier]

Two new phenanthrene glucosides, named 7-hydroxy-4-methoxyphenanthrene-2,8-di-O- β-D-glucoside ( 1), 8-hydroxy-4-methoxyphenanthrene-2,7-di-O- β-D-glucoside ( 2), together with three known compounds, were isolated from the tubers of Cremastra appendiculata (D. Don) Makino. Their structures were elucidated on the basis of spectral data. [ABSTRACT FROM AUTHOR]

Abstract: The multiple roles of light-harvesting chlorophyll a/b-protein complexes in the structure and function of Arabidopsis chloroplasts were investigated using two chlorophyll b-less mutants grown under metal halide lamps with a significant far-red component. In ch1-3, all six light-harvesting proteins of photosystem (PS) II were greatly decreased; in ch1-3lhcb5, Lhcb5 was completely absent while the other five proteins were further decreased. The thylakoids of ch1-3 were less negatively-charged than the wild type, and those of ch1-3lhcb5 were even less so. Despite the expected weaker electrostatic repulsion, however, thylakoids in leaves of the mutants were not well stacked, an effect we attribute to lower van der Waals attraction, lower electrostatic attraction between opposite charges, and the absence or instability of PSII supercomplexes and peripheral light-harvesting trimers. The quantum yield of oxygen evolution in leaves decreased from 0.109 (wild type) to 0.087 (ch1-3) and 0.081 (ch1-3lhcb5) O2 (photon absorbed)−1; we attribute this decrease to an excessive spillover from PSII to PSI, a limited PSII antenna, and increased light-independent thermal dissipation in PSII in the mutants. Destabilization of the donor side of PSII, indicated by slower electron donation to the redox-active tyrosine YZ in ch1-3, probably enhanced PSII susceptibility to photoinactivation, increased the non-functional PSII complexes in vivo, and further inactivated PSII complexes in vitro. The evolution of chlorophyll b-containing chloroplasts seems to fine-tune oxygenic photosynthesis. [Copyright &y& Elsevier]

A new biphenanthrene glucoside, named 2′,7′ -dihydroxy-4,4′-dimethoxy-1,1′-biphenanthrene-2,7-di-O-β-D-glucopyranoside, together with four known compounds, was isolated from the tubers of Cremastra appendiculata. This is the first reported occurrence of a biphenanthrene glucoside in the plant. [ABSTRACT FROM AUTHOR]

Ribosome inactivating proteins (RIPs) like ricin, pokeweed antiviral protein (PAP) and Shiga-like toxins 1 and 2 (Stx1 and Stx2) share the same substrate, the α-sarcin/ricin loop, but differ in their specificities towards prokaryotic and eukaryotic ribosomes. Ricin depurinates the eukaryotic ribosomes more efficiently than the prokaryotic ribosomes, while PAP can depurinate both types of ribosomes. Accumulating evidence suggests that different docking sites on the ribosome might be used by different RIPs, providing a basis for understanding the mechanism underlying their kingdom specificity. Our previous results demonstrated that PAP binds to the ribosomal protein L3 to depurinate the α-sarcin/ricin loop and binding of PAP to L3 was critical for its cytotoxicity. Here, we used surface plasmon resonance to demonstrate that ricin toxin A chain (RTA) binds to the P1 and P2 proteins of the ribosomal stalk in Saccharomyces cerevisiae. Ribosomes from the P protein mutants were depurinated less than the wild-type ribosomes when treated with RTA in vitro. Ribosome depurination was reduced when RTA was expressed in the ΔP1 and ΔP2 mutants in vivo and these mutants were more resistant to the cytotoxicity of RTA than the wild-type cells. We further show that while RTA, Stx1 and Stx2 have similar requirements for ribosome depurination, PAP has different requirements, providing evidence that the interaction of RIPs with different ribosomal proteins is responsible for their ribosome specificity. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Automatic measurement and monitoring of mental fatigue are invaluable for preventing mental-fatigue related accidents. We test an EEG-based mental-fatigue monitoring system using a probabilistic-based support vector-machines (SVM) method. Methods: Ten subjects underwent 25-h sleep deprivation experiments with EEG monitoring. EEG data were segmented into 3-s long epochs and manually classified into 5 mental-fatigue levels, based on subjects’ performance on an auditory vigilance task (AVT). Probabilistic-based multi-class SVM and standard multi-class SVM were compared as classifiers for distinguishing mental fatigue into the 5 mental-fatigue levels. Results: Accuracy of the probabilistic-based multi-class SVM was 87.2%, compared to 85.4% using the standard multi-class SVM. Using confidence estimates aggregation, accuracy increased to 91.2%. Conclusions: Probabilistic-based multi-class SVM not only gives superior classification accuracy but also provides a valuable estimate of confidence in the prediction of mental fatigue level in a given 3-s EEG epoch. Significance: The work demonstrates the feasibility of an automatic EEG method for assessing and monitoring of mental fatigue. Future applications of this include traffic safety and other domains where measurement or monitoring of mental fatigue is crucial. [Copyright &y& Elsevier]

Abstract: By using the supersymmetric WKB approximation approach and the functional analysis method, we solve approximately the Dirac equation with the Eckart potential for the arbitrary spin–orbit quantum number κ. The bound state energy eigenvalues and the associated two-component spinors of the Dirac particles are obtained approximately. [Copyright &y& Elsevier]

Abstract: Objective. : The aim of study was to investigate the proliferative effects of stromal cell-derived factor-1α (SDF-1α) on endometrial carcinomas cell lines with different estrogen receptors (ER) and PTEN protein profiles. Methods. : MTT assays was used to detect the proliferation of HEC-1A and Ishikawa cells, and Western blotted analysis was used to detect activation of Akt and ERK1/2 in both cell lines after exposure to various concentrations of SDF-1α, MAPK-specific inhibitor PD98059 or PI3K-specific inhibitor LY294002. Results. : Low concentrations of SDF-1α (≤50 ng/ml) significantly promoted proliferation of Ishikawa cells but not of HEC-1A, while high concentrations of SDF-1α (>50 ng/ml) induced proliferation in both cell lines. ERK1/2 was significantly activated for more than 2 h by SDF-1α at 20 ng/ml in HEC-1A cells, but not in Ishikawa cells. In contrast, Akt was significantly activated for over 2 h in Ishikawa cells but remained unchanged in HEC-1A cells. High concentrations of SDF-1α activated Akt and ERK1/2 pathways in both cell lines in a dose-dependent manner, which was primarily inhibited by LY294002 for pAkt and by PD98059 for pERK 1/2. Conclusions. : SDF-1α could stimulate the cell proliferation of endometrial carcinoma with different expression status of ER and PTEN in vitro, likely through the activation of both Akt and ERK1/2 signaling pathways. [Copyright &y& Elsevier]