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We present a new on-off assay for alkaline phosphatase (ALP) detection using molybdenum oxide quantum dots (MoO x QDs) based on three favorable properties: the quenching ability of Cu 2+ on MoO x QDs, the strong binding affinity between Cu 2+ and PPi, and the catalysis ability of ALP to hydrolyze PPi to orthophosphate (Pi). Benefiting from the strong affinity of Cu 2+ and PPi, the effective quenching of MoO x QDs by Cu 2+ was hampered when PPi was added into the system containing MoO x QDs and Cu 2+ , leading to a significant photoluminescence enhancement (“ON”). Further addition of ALP, PPi was catalytically hydrolyzed into Pi, which would disable the formation of Cu 2+ -PPi complex and release free Cu 2+ , resulting in photoluminescence quenching (“OFF”). The on-off assay allows the analysis of PPi and ALP by measuring the photoluminescence intensity, and quantitative detection of ALP in a linear range from 0.1 to 5.0 U/L with the detection limit of 0.02 U/L (3σ/K) is realized. Moreover, the present assay was successfully applied in ALP inhibitor screening and ALP detection in diluted human serum samples, and satisfactory recoveries between 99.6% and 103.0% were obtained. The on-off photoluminescence assay shows many merits, including convenient operation, cost-saving, high sensitivity and superior selectivity, which allow the assay for ALP detection in real human serum samples. [ABSTRACT FROM AUTHOR]

Malaria remains a deadly parasitic disease caused by Plasmodium, claiming almost half a million lives every year. While parasite genetics and biology are often the major targets in many studies, it is becoming more evident that host genetics plays a crucial role in the outcome of the infection. Similarly, Plasmodium infections in mice also rely heavily on the genetic background of the mice, and often correlate with observations in human studies, due to their high genetic homology with humans. As such, murine models of malaria are a useful tool for understanding host responses during Plasmodium infections, as well as dissecting host-parasite interactions through various genetic manipulation techniques. Reverse genetic approach such as quantitative trait loci studies and random mutagenesis screens have been employed to discover novel host genes that affect malaria susceptibility in mouse models, while other targeted studies utilize mouse models to validate observation from human studies. Herein, we review the findings from the past and present studies on murine models of hepatic and erythrocytic stages of malaria and speculate on how the current mouse models benefit from the recent development in CRISPR/Cas9 gene editing technology. [ABSTRACT FROM AUTHOR]

Studies the temperature dependence of the transient current in ferroelectric Pb(Zr0.53Ti0.47)O3 thin film capacitors. Examination of the current density versus time characteristics in the temperature range from room temperature to 140 degrees Celsius; Enhancement in the emission rate of captured holes.

Provides information on a study that examined the formation of surface-passivated layers in nanocrystalline iron particles under varied atmospheres and the effects of passivated layers on the magnetic properties of the particles. Methodology of the study; Results and discussion on the study; Conclusions.

• A novel liquid-bridge flow between plate spiral channel was developed. • Liquid-bridge flow provides a longer residence time and larger gas–liquid contact surface. • The specific gas flow channel of spiral string makes the pressure drop extremely low. • The spiral spring has good mass transfer efficiency in carbon dioxide capture. Spiral liquid-bridge flows have significant potential for mass transfer and reactions. However, the spiral liquid-bridge formed by a circular-section spiral pipe column exhibits poor flow performance. Based on the characteristics of the liquid-bridge flow between the plates, the cross section of the spiral spring is optimized to be rectangular. We studied the hydrodynamic properties and mass-transfer performance of a liquid-bridge flow in detail. The flow pattern of the liquid-bridge was observed, and hydrodynamic data were measured. The results showed that the optimized spiral spring residence time and gas–liquid contact area increased. In the gas–liquid absorption experiment, the liquid mass-transfer coefficient, mass-transfer unit height, and pressure drop of the spiral spring were measured. The results showed that the spiral spring exhibited an excellent mass-transfer effect and a low pressure drop. In the experiment on CO 2 capture by MEA, good performance was observed. [ABSTRACT FROM AUTHOR]

Study Design: This study is a computed tomographic-based morphometric analysis of the pediatric occipital bones as related to pediatric occipitocervical fusion.Objective: To quantify reference data concerning the thicknesses of the immature occipital bones to guide the pediatric occipitocervical fusion.Summary Of Background Data: To the best of our knowledge, no published study has provided insight into the thicknesses of pediatric occiputs with different age groups.Methods: 80 pediatric patients were divided into 4 age groups, and their occiputs were studied on Philips Brilliance 256 iCT scan.Results: The mean thickness ± standard deviations of the pediatric occipital bones with different age groups is shown. The median and the paramedian regions are always thicker than the more lateral regions at each age group and the thickest point in the occiputs is mostly at the external occipital protuberance. The mean thickness of occiputs showed an obvious significant difference between each 2 age groups and no significant difference between male and female in different age groups except the group 4.Conclusion: Our investigation provides insight into the anatomy of occiputs in pediatric population and preoperative CT evaluation must be required to further decrease the risk of occipitocervical fusion. [ABSTRACT FROM AUTHOR]

Background: The use of Anti-PD-1 therapy has yielded promising outcomes in hepatocellular carcinoma (HCC). However, limited research has been conducted on the overall survival (OS) of patients with varying tumor responses and treatment duration. Methods: This retrospective study analyzed HCC patients who received sintilimab between January 2019 and December 2020 at four centers in China. The evaluation of tumor progression was based on Response Evaluation Criteria in Solid Tumors version 1.1. The study investigated the correlation between tumor response and OS, and the impact of drug use on OS following progressive disease (PD). Results: Out of 441 treated patients, 159 patients satisfied the inclusion criteria. Among them, 77 patients with disease control exhibited a significantly longer OS compared to the 82 patients with PD (median OS 26.0 vs. 11.3 months, P < 0.001). Additionally, the OS of patients with objective response (OR) was better than that of patients with stable disease (P = 0.002). Among the 47 patients with PD who continued taking sintilimab, the OS was better than the 35 patients who discontinued treatment (median OS 11.4 vs. 6.9 months, P = 0.042). Conclusions: In conclusion, the tumor response in HCC patients who received sintilimab affects OS, and patients with PD may benefit from continued use of sintilimab. [ABSTRACT FROM AUTHOR]

Infrared sensors incorporating suspended zinc oxide (ZnO) pyroelectric films and thermally insulated silicon substrates are fabricated using conventional MEMS-based thin-film deposition, photolithography, and etching techniques. The responsivity of the pyroelectric film is improved via annealing at 500 °C for 4 h. The voltage response of the fabricated sensors is evaluated experimentally for a substrate thickness of 1 µm over a sensing range of 30 cm. The results show that the voltage signal varies as an inverse exponential function of the distance. A positioning system based on three infrared sensors is implemented in LabVIEW. It is shown that the position estimates obtained using the proposed system are in excellent agreement with the actual locations. In general, the results presented in this study provide a useful source of reference for the further development of MEMS-based pyroelectric infrared sensors. [ABSTRACT FROM AUTHOR]

Recently, Jia et al. proposed the quantum private comparison protocol with the genuine four-particle entangled states (Jia et al., Int. J. Theor. Phys. 51(4), 1187-1194 (2012)). Jia et al. claimed that in this protocol, TP cannot obtain Alice and Bob’s secrets and only knows their comparison result. However, in this paper, we demonstrate that if TP is a genuine semi-honest third party, he can totally obtain Alice and Bob’s secrets by launching a particular intercept-resend-measure attack. After suggesting the intercept-resend-measure attack strategy from TP first, we put forward one corresponding improvement to prevent this attack. [ABSTRACT FROM AUTHOR]

In this paper we study an optimization problem arising from a sterilization process for packaged foods by using a microwave heating method. The goal of the optimal control is to find the optimal frequency function such that the temperature profile at the final stage has a relative uniform distribution in the food product. The underlying state variables are electric, magnetic fields and temperature which satisfy the coupled nonlinear Maxwell’s system and a nonlinear heat equation. The control variable for the system is chosen to be the electric frequency function. We show that there exists an optimal frequency which minimizes the cost functional. Moreover, an optimality condition is also derived. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD) is the most common type of liver disease in developed countries. Oxidative stress plays a critical role in the progression of NAFLD. Modern pharmacological study and clinical trials have demonstrated the remarkable antioxidant activity of Gynostemma pentaphyllum (GP) in chronic liver disease. One aim of this study was to explore the potential protective effects and mechanisms of action of GP extract on NAFLD. The in vivo results showed that GP extract could alleviate fatty degeneration and haptic fibrosis in NAFLD mice. For exploring the hepatoprotective mechanisms of GP, we used network pharmacology to predict the potential active components of GP and their intracellular targets in NAFLD. Based on the network pharmacology results, we further utilized biomedical assays to validate this in silico prediction. The results showed that Gypenoside XL could upregulate the protein level of PPARα in NAFLD; the transcription level of several PPARα downstream target genes such as acyl-CoA oxidase (ACO) and carnitine palmitoyltransferase-1 (CPT-1) also increased after Gypenoside XL treatment. The overexpression of ACO and CPT-1 may involve the hepatoprotective effects of GP and Gypenoside XL on NAFLD by regulating mitochondrial fatty acid β-oxidation. [ABSTRACT FROM AUTHOR]

As one of the major active ingredients in Radix Scutellariae, wogonin has been shown to be associated with various pharmacological activities on cancer cell growth, apoptosis, and cell invasion and migration. Here, we demonstrated that wogonin may harbor potential anti-metastatic activities in hepatocarcinoma (HCC). The anti-metastasis potential of wogonin and its underlying mechanisms were evaluated by ligand–protein docking approach, surface plasmon resonance assay, and in vitro gelatin zymography studies. Our results showed that wogonin (100 μM, 50 μM) suppressed MHCC97L and PLC/PRF/5 cells migration and invasion in vitro. The docking approach and surface plasmon resonance assay indicated that the potential binding affinity between wogonin and matrix metalloproteinase-9 (MMP-9) may lead to inhibition of MMP-9 activity and further leads to suppression of tumor metastasis. This conclusion was further verified by Western blot results and gelatin zymography analysis. Wogonin might be a potent treatment option for disrupting the tumor metastasis that favors HCC development. The potential active targets from computational screening integrated with biomedical study may help us to explore the molecular mechanism of herbal medicines. [ABSTRACT FROM AUTHOR]

Objective Diseases of the pancreas, especially pancreatitis, have been implicated as possible risk factors for psychiatric illnesses, such as depression and anxiety disorder. This nested case-control study aimed to investigate the association between diseases of the pancreas and completed suicide in a psychiatric population-based study. Methods The case group comprised 6568 completed suicides (ICD-9: E950-E959, E980-989) patients from the national mortality database between January 1, 2002 and December 1, 2010. These cases were compared with 6568 gender-, age-, residence-, and insurance premium-matched controls. Both suicide and non-suicide study patients were drawn from a group with previous psychiatric diagnoses. The risk of suicide among patients with diseases of the pancreas was analyzed using a conditional logistic regression model that controlled for alcohol-related disorder, drug dependence, schizophrenia, depressive disorder, bipolar disorder, anxiety disorder, Charlson comorbidity score, and outpatient visits. Results Disease of the pancreas was an independent risk factor for psychiatric patients who had completed suicide when adjusted for clinical and other comorbid factors. Among these covariates, alcohol-related disorders partially mediate the suicide risk among patients with disease of the pancreas, and mental disorders may not mediate this suicide risk. Conclusions Diseases of the pancreas were associated with increased risk of completed suicide after controlling for potential confounding factors. [ABSTRACT FROM AUTHOR]

Industrial metabolism has closely impact on urban economic, resources and environment condition. As an intensively consuming-energy and heavily polluting industry, steel industry has emitted extremely large quantitate of CO 2 . Presently, there are two typical production processes in steel enterprises, which are the long process and the short process. However, to compensate the insufficient scrap resources, some steel enterprises have taken a great deal of hot iron in the electric arc furnace steelmaking, which only happens in China. This unique process called the “Chinese style” short process. Coupling material flow analysis and emission factor method, the CO 2 emissions for these different three production processes are analysed and their different carbon flow networks diagram are built. The flow diagram could provide basements on emissions reduction located. Results show that the CO 2 emissions of long process, “Chinese-style” short process and short process are 3.102 t/t-s, 2.994 t/t-s and 1.613 t/t-s, respectively. The focus of CO 2 emissions reduction are the blast furnace steelmaking in long process, electric arc furnace steelmaking in “Chinese-style” short process and short process, whose CO 2 emissions are 2.079 t/t-s, 2.748 t/t-s and 1.367 t/t-s, respectively. Specially, the reason why the CO 2 emissions of “Chinese style” short process are too high is excessive hot iron utility. For lower CO 2 emissions, it is suggested that scrap resources should be recycled as many as possible and the short process ought to rationally develop based on the existing environmental strategies. [ABSTRACT FROM AUTHOR]

A two-party quantum private comparison (QPC) protocol is constructed with χ-type entangled states in this paper. The proposed protocol employs a semi-honest third party (TP) that is allowed to misbehave on his own but cannot conspire with the adversary. The proposed protocol need perform Bell basis measurements and single-particle measurements but neither unitary operations nor quantum entanglement swapping technology. The proposed protocol possesses good security toward both the outside attack and the participant attack. TP only knows the comparison result of the private information from two parties in the proposed protocol. [ABSTRACT FROM AUTHOR]

Allelic heterogeneity is a common phenomenon where a gene exhibits a different phenotype depending on the nature of its genetic mutations. In the context of genes affecting malaria susceptibility, it allowed us to explore and understand the intricate host-parasite interactions during malaria infections. In this study, we described a gene encoding erythrocytic ankyrin-1 (Ank-1) which exhibits allelic-dependent heterogeneous phenotypes during malaria infections. We conducted an ENU mutagenesis screen on mice and identified two Ank-1 mutations, one resulting in an amino acid substitution (MRI95845), and the other a truncated Ank-1 protein (MRI96570). Both mutations caused hereditary spherocytosis-like phenotypes and confer differing protection against Plasmodium chabaudi infections. Upon further examination, the Ank-1(MRI96570) mutation was found to inhibit intraerythrocytic parasite maturation, whereas Ank-1(MRI95845) caused increased bystander erythrocyte clearance during infection. This is the first description of allelic heterogeneity in ankyrin-1 from the direct comparison between two Ank-1 mutations. Despite the lack of direct evidence from population studies, this data further supported the protective roles of ankyrin-1 mutations in conferring malaria protection. This study also emphasized the importance of such phenomena in achieving a better understanding of host-parasite interactions, which could be the basis of future studies. [ABSTRACT FROM AUTHOR]

In nature, proteins self-assemble into various structures with different dimensions. To construct these nanostructures in laboratories, normally proteins with different symmetries are selected. However, most of these approaches are engineering-intensive and highly dependent on the accuracy of the protein design. Herein, we report that a simple native protein LecA assembles into one-dimensional nanoribbons and nanowires, two-dimensional nanosheets, and three-dimensional layered structures controlled mainly by small-molecule assembly-inducing ligands RnG ( n=1, 2, 3, 4, 5) with varying numbers of ethylene oxide repeating units. To understand the formation mechanism of the different morphologies controlled by the small-molecule structure, molecular simulations were performed from microscopic and mesoscopic view, which presented a clear relationship between the molecular structure of the ligands and the assembled patterns. These results introduce an easy strategy to control the assembly structure and dimension, which could shed light on controlled protein assembly. [ABSTRACT FROM AUTHOR]

In nature, proteins self-assemble into various structures with different dimensions. To construct these nanostructures in laboratories, normally proteins with different symmetries are selected. However, most of these approaches are engineering-intensive and highly dependent on the accuracy of the protein design. Herein, we report that a simple native protein LecA assembles into one-dimensional nanoribbons and nanowires, two-dimensional nanosheets, and three-dimensional layered structures controlled mainly by small-molecule assembly-inducing ligands RnG ( n=1, 2, 3, 4, 5) with varying numbers of ethylene oxide repeating units. To understand the formation mechanism of the different morphologies controlled by the small-molecule structure, molecular simulations were performed from microscopic and mesoscopic view, which presented a clear relationship between the molecular structure of the ligands and the assembled patterns. These results introduce an easy strategy to control the assembly structure and dimension, which could shed light on controlled protein assembly. [ABSTRACT FROM AUTHOR]

In this paper we study a model which describes the pattern formation of vegetation spots and strips in a semi-arid or arid landscape. The mathematical model consists of a nonlinear cross-diffusion system with evaporation and absorption sources. Global existence and uniqueness in classical sense for the system are established. Some asymptotic behaviors of the solution are derived for a linearized system. It is shown that the solution of the linearized system is asymptotically stable near the steady-state solution. Moreover, we show that the Turing phenomenon occurs for the linearized cross-diffusion system and the cross-diffusion destabilizes the ecosystem. [ABSTRACT FROM AUTHOR]

Discusses the measurement and analysis of the time dependent dielectric breakdown (TDDB) involving the barium-strontium-titanate (BST) capacitors. Importance of the BST material for dynamic random access memory capacitor applications; How BST thin films are prepared; Reference to the leakage currents in BST films.

In the catabolism of lignin-derived biphenyl by Sphingobium sp. SYK-6, LigZ catalyzes the cleavage of 2,2′,3-trihydroxy-3′-methoxy-5,5′-dicarboxybiphenyl (OH-DDVA) to a meta-cleavage product (MCP) identified here as 4,11-dicarboxy-8-hydroxy-9-methoxy-2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate (DCHM-HOPDA). DCHM-HOPDA is transformed nonenzymatically, likely to a lactone ( k = 0.13 ± 0.01 min−1, pH 7.5). This is hydrolyzed to the dienolate at alkaline pH (apparent p Ka ~ 11.3). Only the dienolate is a substrate for LigY, the putative MCP hydrolase. LigZ has higher specificity for OH-DDVA ( kcat/ Km = 2.20 ± 0.02 × 107 s−1· m−1) than for protocatechuate (PCA; 6 ± 1 × 102 s−1· m−1). PCA also inactivates LigZ (partition ratio of 50), but at rates too low to be physiologically relevant. This study provides insight into the bacterial catabolism of lignin and facilitates the study of downstream catabolic enzymes. [ABSTRACT FROM AUTHOR]

Nonlinear features extracted from Lamb wave signals (e.g., second harmonic generation) are demonstrably sensitive to microscopic damage, such as fatigue and material thermal degradation. While a majority of the existing studies in this context is focused on detecting undersized damage in metallic materials, the present study is aimed at expanding such a detection philosophy to the domain of composites, by linking the relative acoustic nonlinearity parameter (RANP) – a prominent nonlinear signal feature of Lamb waves – to barely visible impact damage (BVID) in composites. Nevertheless, considering immense uncertainties inevitably embedded in acquired signals (due to instrumentation, environment, operation, computation/estimation, etc.) which can adversely obfuscate nonlinear features, it is necessary to quantify the uncertainty of the RANP (i.e., its statistics) in order to enhance decision-making associated with its use as a detection feature. A probabilistic model is established to numerically evaluate the statistical distribution of the RANP. Using piezoelectric wafers, Lamb waves are acquired and processed to produce histograms of RANP estimates in both the healthy and damaged conditions of a CF/EP laminate, to which the model is compared, with good agreement observed between the model-predicted and experimentally-obtained statistic distributions of the RANP. With the model, BVID in the laminate is predicted. The model is further made use of to quantify the level of confidence in damage prediction results based on the concept of a receiver operating characteristic , enabling the practitioners to better understand the obtained results in the presence of uncertainties. [ABSTRACT FROM AUTHOR]

The development of a site-specific and covalent attachment methodology is crucial for antibody–biotin conjugates to preserve the antigen-binding ability of antibodies and yield homogeneous products. In this study, an engineered photoactivatable Z-domain variant [an UV-active amino acid benzoylphenylalanine (Bpa) was genetically incorporated into the Z-domain] carrying one biotin molecule (Z Bpa –Biotin) was prepared by employing aminoacyl-tRNA synthetase/suppressor tRNA and Avitag/BirA techniques. The site-specific and covalent attachment of IgG–biotin conjugates, viz. photo-biotinylated IgG, was successfully achieved after UV exposure by combining the inherent Fc-binding capability of the Z-domain with the formation of covalent bond by the photo-crosslinker. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis assay showed that more than 90% of IgGs conjugated with Z Bpa –Biotin molecules suffered 3 h UV irradiation. Further pepsin digestion analysis confirmed that the Z Bpa –Biotin was conjugated to the Fc fragment of IgG without interference. We took the tumor biomarker carcinoembryoic antigen (CEA) as model to evaluate the detection efficiency of the site-specific photo-biotinylated IgG in biosensing application using surface plasmon resonance (SPR) technology. The photo-biotinylated IgG coated surface gave a limit of detection (LOD) of 2 ng mL -1 , is 5-fold lower than that of the randomly NHS-biotinylated IgG (10 ng mL -1 ). Given that the (strept)avidin–biotin complex is extensively used in immunoassays, the proposed method for biotinylated IgG provides a powerful approach to further expand related applications. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to develop a novel method for observing the morphology of the blood vessels in the rabbit endplate.Methods: Twenty 6-month-old rabbits were used in this study. The blood vessels in the L5 endplate in Group A were injected with iohexol and Group B with barium sulfate. Group C was the control group with saline. To optimize the study, Group B was divided into two subgroups: Group B-1 was injected with 100% (w/v) barium sulfate and Group B-2 with 50% (w/v). After injection, the L4-L5 vertebral body was excised and the cranial endplate of L5 was scanned using a micro-CT scanner. Models of the vertebral endplate and vessels were reconstructed using the 3D reconstruction software (Mimics 16.0) by calculating a bone threshold value, and then merged these two models to create a superimposed model.Results: The 3D vessel models could not be created in Groups A and C, but they were clearly visualized in Group B. In the 3D model, the blood vessels extended from the subchondral bone to the endplate, and the density of the blood vessels in the area of the nucleus pulposus (NP) was higher than in the annulus fibrosus.Conclusions: The results of this study suggest that the blood vessels in the rabbit endplate can be clearly observed by the method described using barium sulfate [the 50% (w/v) gave better results compared with the 100% (w/v)]. The information from the 3D vessel structure could provide essential data to help us understand the nutrient pathways within the vertebral endplate. [ABSTRACT FROM AUTHOR]

The injection process of powder fuel directly affects the scramjet operating performance. This study analyzes gas-particle two-phase flow during powder fuel injection. The macroscopic behavior of powder fuel jets under different injection pressure conditions is characterized using the high-speed shadow imaging technology. Simultaneously, the coupled model of computational fluid dynamics-discrete element method is employed to determine the experimental conditions, and the flow field structure and gas-particle interactions are analyzed. The results show that the development of powder fuel jets mainly occurs in three stages: the low-speed development stage, the high-speed development stage, and the stable stages. A long transition period exists between different stages, and the transition time decreases with increasing injection pressure. In the low-speed development stage, the powder fuel jet initially develops slowly and then develops rapidly. In the high-speed development stage, the jet initially develops rapidly and then develops slowly. The jet in the stable stage is classified into the powder particle, fluidized gas, and free flow regions. The distribution range of the particles decreases with increasing injection pressure. The fluidized gas velocity and drag force curve on the axis experience many fluctuations, and the particle velocity is almost always accelerated. Fluidized gas velocity, drag force, particle velocity, and particle acceleration distance increase with the injection pressure. [Display omitted] • The macroscopic behavior of the powder fuel jets was characterized by high-speed shadow imaging technology. • Three stages of the development of powder fuel jets were discovered. • It is found that the jet shows obvious stratification in the stable stage. • The flow process of the gas-particle two-phase jet was studied in detail. [ABSTRACT FROM AUTHOR]

Synthesis and catalytic activity of palladium complexes of 8-(pyridin-2-ylmethoxy)quinolinone ( 3) were investigated. Complexation of 3 with [Pd(CH3CN)2Cl2] gave the dimeric palladium complex [{ N, N-( 3)PdCl}2] ( 4). The structure of 4 was characterized by 1H/13C NMR spectroscopy and mass spectrometry, and further confirmed by X-ray crystallography. Complex 4 acts as a catalyst for oxidative cleavage of C=C bonds, and it catalyzes the hydration of styrenes in an anti-Markovnikov Wacker manner to give terminal aldehydes as the initial product, which then undergo C-C cleavage to yield the corresponding benzaldehydes. Systematic studies of this catalysis were performed. [ABSTRACT FROM AUTHOR]

In this paper we consider the heat equation u t = ∆ u in a unbounded domain Ω ⊂ R N with a Neumann boundary condition u v = u p , where p > 1 and v is the exterior unit normal on ∂ Ω. It is shown for various type of domains that there exists a critical number p c (Ω) ≥ 1, such that all of positive solutions blow up in a finite time when p ∈ (1, p c ] while there exist positive global solutions if p > p c and initial data are small. [ABSTRACT FROM AUTHOR]

Objective: Suicide attempters might be sent to the emergency room for urgent medical intervention. Some with more severe physical morbidity may be hospitalised, and psychiatrists might be consulted for suicide evaluation. The aim of our study was to investigate the three-year all-cause mortality rate of hospitalised suicide attempters with regard to the effect of consultation-liaison services, and to identify any risk factors associated with mortality. Methods: Between 2002 and 2006, 196 inpatients from medical or surgical wards in a general hospital who had consulted psychiatrists because of suicide attempts were collected consecutively. We traced their mortality incidence during a three-year period, and calculated the mortality rate and time (days) to death. Results: Three-year all-cause mortality was 20.4%, and there was a higher risk of mortality in the first two years after the index suicide attempt. In the adjusted Cox regression model, associated risks included male gender, older age, diagnosis of depressive disorders and lack of psychiatric follow-up. Conclusions: We found that hospitalised suicide attempters had higher all-cause mortality after discharge, and determined that psychiatric follow-up is helpful. More attention should be paid to those with potential risk factors, and timely intervention is suggested in order to reduce mortality. [ABSTRACT FROM AUTHOR]

Objectives Circulating chronic lymphocytic leukemia (CLL) cells appear not to be overly utilizing aerobic glycolysis. However, recurrent contact with CLL cells in a stromal microenvironment leads to increased aerobic glycolysis and the cells’ overall glycolytic capacity, which promotes cell survival and proliferation. TP53-induced glycolysis and apoptosis regulator (TIGAR) has been directly implicated in cellular metabolism in the control of glycolysis. TIGAR inhibits glycolysis and protects cells from intracellular reactive oxygen species (ROS)-associated apoptosis. Methods TIGAR mRNA expression was investigated by quantitative PCR in 102 newly diagnosed CLL patients. Furthermore, the relationship between the expression of TIGAR and its clinical characteristics and prognosis were investigated. Moreover, we also investigated the correlation between TIGAR expression and apoptosis in primary CLL cells. Results Our data revealed that TIGAR overexpression was correlated with the protection from spontaneous apoptosis in CLL cells, and is strongly associated with advanced Binet stage, unmutated immunoglobulin heavy-chain variable region ( IGHV ) status, CD38 positivity, β2-microglobulin and p53 aberrations. Higher expression of TIGAR was associated with shorter treatment-free survival (median: three months vs. 51 months, P = 0.0108), worse overall survival (median: 74 months vs. not reached, P = 0.0242), and the diverse responses to fludarabine-based chemotherapy. TIGAR expression in patients resistant to chemotherapy was significantly higher than in patients sensitive to chemotherapy (mean: 0.3859 ± 0.1710 vs. 0.0974 ± 0.0291, P = 0.0290). Conclusion Taken together, our findings revealed that high TIGAR expression is closely correlated with worse clinical outcome in CLL patients, and depicted how bioenergetic characteristics could be therapeutically exploited in CLL. [ABSTRACT FROM AUTHOR]

Targeting recombinant proteins at highly extracellular production in the culture medium of Escherichia coli presents a significant advantage over cytoplasmic or periplasmic expression. In this work, a recombinant protein between ZZ protein and alkaline phosphatase (rZZ–AP) was constructed. Because rZZ-AP has the IgG-binding capacity and enzymatic activity, it can serve as an immunoreagent in immunoassays. However, only a very small portion of rZZ–AP is generally secreted into the aqueous medium under conventional cultivation procedure. Hence, we emphasized on the optimization of the culture procedures and attempted to dramatically enhance the yield of extracellular rZZ–AP from E. coli HB101 host cells by adding sucrose, glycine, and Triton X-100 in the culture medium. Results showed that the extracellular production of rZZ–AP in the culture medium containing 5% sucrose, 1% glycine, and 1% Triton X-100 was 18.6 mg/l, which was 18.6-fold higher than that without the three chemicals. And the β-galactosidase activity test showed that the increased extracellular rZZ–AP was not due to cell lysis. Further analysis suggested a significant interaction effect among the three chemicals for the enhancement of extracellular production. Ultrastructural analysis indicated that the enhancement may be due to the influence of sucrose, glycine, and Triton X-100 on the periplasmic osmolality, permeability, or integrity of the cell wall, respectively. This proposed approach presents a simple strategy to enhance the extracellular secretion of recombinant proteins in the E. coli system at the process of cell cultivation. [ABSTRACT FROM AUTHOR]

Saccharopolyspora erythraea E3 is an important industrial strain for erythromycin production and knowledge on its metabolism is limited. In the present work, 13 C labeling experiments were conducted to characterize the metabolism of S. erythraea E3. We found that S. erythraea E3 was difficult to grow on minimal medium with glucose as sole carbon source and the addition of proline remarkably improved the cell growth. The activity of EMP pathway was very low and ED pathway was alternatively the main glucose utilization pathway. The addition of proline resulted in remarkable changes in the fluxes of central metabolism. The fluxes in PP pathway, in TCA cycle and in ED pathway were 90% higher, 64% and 31% lower on Glc/Pro than on Glc, respectively. The maintenance energy on Glc/Pro was 58.4% lower than that on Glc. The energy charge was lower on Glc than on Glc/Pro, indicating that the cells on Glc suffered from energy burden. This study elucidates the impacts of proline on the central metabolism of S. erythraea and deepens the understanding of its metabolism. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is a particle therapy that involves the use of boron-containing drugs and neutron irradiation for the treatment of tumors, such as head and neck cancer. Boron atoms accumulated in a tumor capture neutrons through the nuclear reaction, then generating charged particles responsible for the therapeutic action. However, other elements in the patient's tissues or metal implants are activated during the treatment. Therefore, patients emit radiation after receiving BNCT. In this study, to develop release criteria for patients who have received BNCT, patients underwent spectroscopy using calibrated high-purity germanium to identify which elements were activated during the procedure. The ambient dose equivalent rate, H ˙ ∗ (10), was measured at the surface of a patient's treatment site and 1 m away from the patient using a plastic dosimeter. This cohort study included 84 patients and was conducted from March 2017 to February 2020. The predominant radionuclides activated during the procedures were 49Ca, 38Cl, and 24Na. According to the International Commission on Radiological Protection Publication 103, the European Commission Radiation Protection No. 194 report, and the United States Nuclear Regulatory Commission Regulatory Guide 8.39, the main criterion for the release of patients following BNCT comprises an ambient dose equivalent rate lower than 10 μSv/h at a distance of 1 m from the patient. All of the patients in this study exhibited a rate lower than this limit. The average ambient dose equivalent rate measured at the surfaces of the patients' treatment sites was approximately 30–50 μSv/h. The maximum occupational exposure of the BNCT staff from patient-emitted radiation was approximately 20 μSv per 20-min treatment course. • Predominant activated radionuclides of 50 BNCT patients were 49Ca, 38Cl, and 24Na. • Release criteria of BNCT patients is the ambient dose equivalent rate of 10 μSv/h at 1 m. • Occupational exposure from patient to BNCT staff in 20 min was about 20 μSv. [ABSTRACT FROM AUTHOR]

The etiology of epilepsy remains undefined in two-thirds of patients. Here, we identified a de novo variant of ATP1A2 (c.2426 T > G, p.Leu809Arg), which encodes the α2 subunit of Na+/K+-ATPase, from a family with idiopathic epilepsy. This variant caused epilepsy with hemiplegic migraine in the study patients. We generated the point variant mouse model Atp1a2 L809R , which recapitulated the epilepsy observed in the study patients. In Atp1a2 L809R/WT mice, convulsions were observed and cognitive and memory function was impaired. This variant affected the potassium binding function of the protein, disabling its ion transport ability, thereby increasing the frequency of nerve impulses. Valproate (VPA) and Carbamazepine (CBZ) have limited therapeutic efficacy in ameliorating the epileptic syndromes of Atp1a2 L809R/WT mice. Our work revealed that ATP1A2 L809R variants cause a predisposition to epilepsy. Moreover, we provide a point variant mouse model for epilepsy research and drug screening. ● ATP1A2 L809R is an epilepsy-causing variant. ● The Na+/K+ pump current is lower in the L809R variant, which caused neuronal hyperexcitation. ● A new genetic epilepsy mouse model with a single point variant is generated. [ABSTRACT FROM AUTHOR]

Shales contain abundant organic matter, and have complex mineral composition and developed nanopores. Shale porosity has large surface area and a strong gas adsorption capacity. The specific surface area (SSA) of shales is an important factor for the adsorption of shale gas, while there are several factors which can affect the test results of SSA. In this study, shales collected from Longmaxi formation in the south of Sichuan Basin were taken as the research object. A set of testing methods were established for determining shale SSA through low-pressure N 2 adsorption-desorption method. Following this, the key factors affecting shale SSA were investigated. The results show that particle size of shale samples has little effect on the SSA, and the recommended particle size for SSA measurement is about 3 mm. After 3-h heating treatment at 200 °C, most of adsorbed water and part of the interlayer water of clay minerals are removed, and the tested SSA is highest. Therefore, the recommended optimum degassing temperature is 200 °C. The content of total organic carbon and the SSA have positive linear relationship. The quartz content and the SSA show a good positive correlation. No positive correlation is found between the SSA and other mineral components. The SSA is of great significance for the evaluation of shale gas resources potential. [ABSTRACT FROM AUTHOR]

Vanadium chemistry is of interest due its biological relevance and medical applications. In particular, the interactions of high-valent vanadium ions with sulfur-containing biologically important molecules, such as cysteine and glutathione, might be related to the redox conversion of vanadium in ascidians, the function of amavadin (a vanadium-containing anion) and the antidiabetic behaviour of vanadium compounds. A mechanistic understanding of these aspects is important. In an effort to investigate high-valent vanadium-sulfur chemistry, we have synthesized and characterized the non-oxo divanadium(IV) complex salt tetraphenylphosphonium tri-μ-methanolato-κ6 O: O-bis({tris[2-sulfanidyl-3-(trimethylsilyl)phenyl]phosphane-κ4 P, S, S′, S′′}vanadium(IV)) methanol disolvate, (C24H20P)[VIV2(μ-OCH3)3(C27H36PS3)2]·2CH3OH. Two VIV metal centres are bridged by three methanolate ligands, giving a C2-symmetric V2(μ-OMe)3 core structure. Each VIV centre adopts a monocapped trigonal antiprismatic geometry, with the P atom situated in the capping position and the three S atoms and three O atoms forming two triangular faces of the trigonal antiprism. The magnetic data indicate a paramagnetic nature of the salt, with an S = 1 spin state. [ABSTRACT FROM AUTHOR]

This paper presents a crystal-less clock generator using an automatic process and temperature variation calibration technique. The crystal-less clock generator comprises a voltage-controlled oscillator (VCO), differential-input-single-output (DISO) circuit, and frequency-to-voltage converter (FVC). The VCO was developed using a four-stage differential ring oscillator to generate an output frequency of 25 MHz. The DISO circuit ensures a full-swing output voltage swing of the clock generator and a 50% duty cycle. The output clock is integrated by the FVC circuit to generate an analog voltage signal to control the VCO's oscillation frequencies. The FVC can compensate and calibrate the VCO to provide a stable output frequency through the closed-loop system. The chip was fabricated using a 0.18 µm standard CMOS process with a 0.9 V supply voltage. The measured temperature coefficient was 513 ppm/°C in the temperature range of −40°C to 125°C at a 25-MHz output frequency. [ABSTRACT FROM AUTHOR]

Der(5;17)(p10;q10) is a recurrent but rare aberration reported in myeloid neoplasms (MNs). We report 48 such patients including 19 acute myeloid leukemia (AML) and 29 myelodysplastic syndrome (MDS), to characterize their clinicopathological features. There were 29 men and 19 women, with a median age of 61 years (range, 18–80). 62.5% patients had therapy-related diseases (t-MNs), 70.8% had multilineage dysplasia and 83.3% showed complex karyotypes. In 39 patients tested, FLT3 , NPM1 , CEBPA , KIT were all wild type and NRAS, KRAS, IDH1, APC , TET2 mutations were detected in single case(s) respectively. TP53 mutations were identified in 8 of 10 cases (80%) tested. Median disease-free survival (DFS) and overall survival (OS) were 3 and 10 months, respectively and did not differ between AML or MDS cases, or between de novo versus therapy-related cases, or between the groups with or without complex karyotypes. In 19 patients who achieved complete remission after chemotherapy, and in 9 patients who underwent stem cell transplantation, the OS was better (14 and 17.5 months , P  = 0.0128 and P  = 0.0086, respectively). The der(5;17)(p10;q10) represents a unique molecular-cytogenetic subgroup in t-MNs and, associated with complex karyotypes. TP53 inactivation, resulting from 17p deletion coupled with TP53 mutation, likely contributes to the poor clinical outcome of these patients. [ABSTRACT FROM AUTHOR]

A novel hydrophobically modified polyacrylamide p(AM/NaA/OP-10-AC/BOAM) was successfully synthesized via an aqueous micellar copolymerization method from acrylamide (AM), sodium acrylate (NaA), octylphenol polyoxyethylene acrylate (OP-10-AC), and small amounts of N-benzyl-N-octylacrylamide (BOAM), with the aim of investigating the copolymer's rheological behaviors under various conditions such as polymer concentration, shearing, temperature, and salinity. The copolymer was characterized by infrared spectroscopy, scanning electron microscopy, and atomic force microscope. Scanning electron micrographs show large aggregates in solution formed by the association from the hydrophobic groups of the copolymer. Compared with partially hydrolyzed polyacryamide (HPAM), the copolymer shows a much higher thickening capability and a much greater ability to resist shearing, heat, and salts. This good property of the copolymer is attributed to its three-dimensional dimensional network structure. According to the core flooding test, it can be obtained that oil recovery is enhanced about 4.3% by the copolymer flooding contrasted to the HPAM flooding in mid-low permeability cores under conditions of 1500 mg/L of polymers and 45°C. All the results prove that the copolymer has the capability of increasing oil recovery by improving waterflood sweep efficiency in high-salinity reservoirs. [ABSTRACT FROM PUBLISHER]

Variable selection can be realized through model selection. On this basis, a Euclidean distance-based method for variable selection is proposed in this paper. The preference of a model is determined based on Euclidean distance, and the preference of a variable is determined based on a weighted frequency of the variable appearing in a model. The proposed method is compared with two relative entropy-based methods using a geological sample classification problem, and is proved more reasonable and feasible. The proposed method is extended to ordered geological classification problems and applied in prediction of rock burst classification. The analysis results verify the feasibility of this method. The proposed method can be further applied into analysis of various geological data. [ABSTRACT FROM PUBLISHER]

In this paper, we study an American option-pricing model with an uncertain volatility. Some properties for the option price are derived. Particularly, a global spread for the option price is proved when the volatility depends on the underlying security and time. This result confirms the observed fact from the real financial data in option markets. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The example of the preparation of nano- and micro-scaled, coral-shaped and core-shell topological morphology of copolyethylene particles promoted by the novel heterogeneous non-metallocene catalyst ( m-CHPhO)TiCl/carbon nanotubes (CNTs) was reported. Mass fraction of titanium component of the catalyst was 4.0 wt% determined by ICP analysis. The catalyst system can effectively catalyze polymerization of ethylene and copolymerization of ethylene with 1-hexene. Morphological examination of the obtained polymer particles was carried out by scanning electron microscope (SEM) and high resolution transmission electron microscope (HR-TEM) technique. The results revealed that the morphology of the nascent copolyethylene particles looked like coral shape with size in micro-scaled and featured the core-shell structure consisting of CNTs as the core and copolyethylene as the shell. [ABSTRACT FROM AUTHOR]

Forkhead box protein O1 (FOXO1) is a multifunctional transcription factor of the forkhead family. It may function as a tumor suppressor through its ability to regulate cellular events, including cell proliferation, apoptosis, and cell cycle control. As reported, FOXO1 is downregulated in papillary thyroid carcinoma (PTC). However, the function of FOXO1 in human PTC remains unclear. In this study, we investigated the function and underlying regulatory mechanisms of FOXO1 in PTC cells. PTC cell lines K1 and TPC1 were transiently transfected with FOXO1 small interfering RNA (siRNA) and negative control RNA. Successful transfection was confirmed by RT-qPCR and Western blot analysis. 3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide cell proliferation assays, colony formation assays, apoptosis, and cell cycle assays were used to explore the potential function of FOXO1 in the PTC cell lines. We found that downregulation of FOXO1 promoted cellular proliferation, enhanced clonogenesis, and inhibited cellular apoptosis. However, the cell cycle was not markedly affected by FOXO1 siRNA. Furthermore, Bim, a downstream target of the Akt/FOXO1 signaling pathway, was downregulated at both mRNA and protein levels in cells transfected with FOXO1 siRNA. Collectively, these results indicate that FOXO1 may play an important role in inhibiting PTC development by regulating cellular proliferation, growth, and apoptosis. FOXO1 expression is a potentially useful biomarker for human PTC. Moreover, tumorigenesis of PTC may be associated with repression of the Akt/FOXO1/Bim signaling pathway. [ABSTRACT FROM AUTHOR]

In this work, the effect of partially hydrolyzed polyacrylamide (HPAM) on the oil–water interfacial properties of produced water from polymer flooding (PWPF) was investigated. In addition, this study investigated the effects of three fiocculants (polyaluminium chloride PAC, cationic polymer FO4800SH, and nonionic polymer 402) on the stability of PWPF. The experimental results demonstrate that the addition of HPAM enhances the emulsion stability by increasing viscosity, zeta potential, interfacial tension and interfacial dilational viscoelasticity. The molecular weight and hydrolysis degree of HPAM have no significant influences on these properties. The stability of PWPF can be enhanced by increasing HPAM concentration. Dependency of frequency and concentration was observed for the interfacial dilational viscoelasticity. With the addition of HPAM, the dilational viscoelasticity not only increases with HPAM concentration but runs through a maximum at a concentration of 300 mg/L. As the oscillating frequency increases, the dilational modulus and dilational elasticity increase but the dilational viscosity decreases. The three flocculants can reduce the stability of the emulsion by considerably decreasing the absolute value of zeta potential of oil droplets. FO4800SH has a greater ability than PAC and 402 to separate oil from the emulsion. But the demulsification efficiencies of the three flocculants are not satisfactory because of the presence of HPAM residue. Further research is needed to find more efficient methods to achieve excellent performance of oil–water separation towards PWPF. [ABSTRACT FROM AUTHOR]

The interaction between graphene and other materials is of great importance for its potential applications in nanotechnology. In this paper, by using all atom molecular dynamics simulations, we systematically investigate the self-assembly of fullerenes (diameter from 0.7 to 2.3 nm ) and graphene at room temperature ( 300 K ). It is found that single fullerene can be wrapped by graphene nanoribbon (GNR) due to the van der Waals interaction between them. However, if the GNR is wide enough, the fullerene will only bind to the surface of GNR. To overcome the bending energy of wide GNR, we further use multiple fullerenes, and find that they can self-assemble into various structures. Importantly, fullerenes show dramatically different behaviors as the size changes. Giant fullerenes can work together to scroll a very large graphene from the corner, while this effect is weakened or even disappears in the cases of smaller ones. Finally, we also find that the wrapping process can be completely retarded by adding a substrate below the graphene flake. [ABSTRACT FROM AUTHOR]

Commutation failure (CF) may be caused by AC fault in AC/DC interconnected system, and it will affect the performance of distance protection. The transient characteristic of equivalent current of power-frequency of the dc-ac inverter is first analysed by introducing the concept of quadrant. Then, the effect of CF on distance protection is studied in detail with consideration of the connection mode of distance relay. The analysis results show that both the fault position and fault resistance contribute to the effect of CF on the performance of distance protection significantly. Furthermore, a novel countermeasure based on the amplitude of second harmonic is put forward, and a concept of 'successive trip' by using the change of measured reactance is also presented. Simulation results based on PSCAD/ EMTDC prove the correctness of these conclusions. [ABSTRACT FROM AUTHOR]

The temporal signal features of linear guided waves, as typified by the time-of-flight (ToF), have been exploited intensively for identifying damage, with proven effectiveness in locating gross damage in particular. Upon re-visiting the conventional, ToF-based detection philosophy, the present study extends the use of temporal signal processing to the realm of nonlinear Lamb waves, so as to reap the high sensitivity of nonlinear Lamb waves to small-scale damage ( e.g ., fatigue cracks), and the efficacy of temporal signal processing in locating damage. Nonlinear wave features ( i.e ., higher-order harmonics) are extracted using networked, miniaturized piezoelectric wafers, and reverted to the time domain for damage localization. The proposed approach circumvents the deficiencies of using Lamb wave features for evaluating undersized damage, which are either undiscernible in time-series analysis or lacking in temporal information in spectral analysis. A probabilistic imaging algorithm is introduced to supplement the approach, facilitating the presentation of identification results in an intuitive manner. Through numerical simulation and then experimental validation, two damage indices (DIs) are comparatively constructed, based, respectively, on linear and nonlinear temporal features of Lamb waves, and used to locate fatigue damage near a rivet hole of an aluminum plate. Results corroborate the feasibility and effectiveness of using temporal signal features of nonlinear Lamb waves to locate small-scale fatigue damage, with enhanced accuracy compared with linear ToF-based detection. Taking a step further, a synthesized detection strategy is formulated by amalgamating the two DIs, targeting continuous and adaptive monitoring of damage from its onset to macroscopic formation. [ABSTRACT FROM AUTHOR]

Background: Anti-programmed cell death ligand 1/vascular endothelial growth factor inhibition, coupled with chemotherapy, may potentiate antitumor immunity leading to enhanced clinical benefit, but it has not been investigated in advanced biliary tract cancer (BTC). Objectives: We investigated the efficacy and safety of atezolizumab, bevacizumab, and gemcitabine plus oxaliplatin (GEMOX) in advanced BTC and explore the potential biomarkers related to the response. Design: Multicenter, single-arm, retrospective study. Methods: Advanced BTC patients, who received a triple combination therapy at three medical centers between 18 March 2020 and 1 September 2021, were included. Treatment response was evaluated via mRECIST and RECIST v1.1. Endpoints included the overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety. The whole exome sequencing of pathological tissues was conducted for bioinformatic analysis. Results: In all, 30 patients were enrolled. The best ORR was 76.7% and the DCR was 90.0%. The median PFS was 12.0 months, and the median OS was not reached. During the treatment, 10.0% (3/30) of patients suffered from ⩾grade 3 treatment-related adverse events (TRAEs). Furthermore, fever (73.3%), neutropenia (63.3%), increased aspartate transaminase and alanine aminotransferase levels (50.0% and 43.3%, respectively) are the most common TRAEs. Bioinformatics analysis revealed patients with altered ALS2CL had a higher ORR. Conclusion: The triple combination of atezolizumab, bevacizumab, and GEMOX may be efficacious and safe for patients with advanced BTC. ALS2CL may be a potential predictive biomarker for the efficacy of triple combination therapy. [ABSTRACT FROM AUTHOR]

To improve the conditions of powder bentonite-steel slag forming, the composite adsorption particles were prepared from calcium-based bentonite and steel slag with the help of cross-linking of sodium alginate and calcium chloride. The post-adsorption morphology, elemental and physical phases of the composite particles were characterized by SEM-EDS and XRD analysis. The effect of composite adsorption particles on the adsorption of Cu (11) at different slag mass ratios, dosing amounts, pH, temperature and initial concentration was investigated by static adsorption experiments. The results showed that the removal rate of Cu(II) reached 92.95% at a compound particle dosage of 30 g/L, pH 5.2 and an initial Cu(II) concentration of 100 mg/L. The kinetics of Cu(II) adsorption by the composite particles is in accordance with the proposed first-order kinetic model, the adsorption thermodynamics is in accordance with the Lang-muir adsorption isotherm model, and the thermodynamically relevant parameters indicate that the adsorption of Cu(II) by the composite particles is a spontaneous, heat-absorbing procees. [ABSTRACT FROM AUTHOR]

Commutation failure (CF) may be caused by AC fault in AC/DC interconnected system, and it will affect the performance of distance protection. The transient characteristic of equivalent current of power‐frequency of the dc–ac inverter is first analysed by introducing the concept of quadrant. Then, the effect of CF on distance protection is studied in detail with consideration of the connection mode of distance relay. The analysis results show that both the fault position and fault resistance contribute to the effect of CF on the performance of distance protection significantly. Furthermore, a novel countermeasure based on the amplitude of second harmonic is put forward, and a concept of 'successive trip' by using the change of measured reactance is also presented. Simulation results based on PSCAD/EMTDC prove the correctness of these conclusions. [ABSTRACT FROM AUTHOR]