27 research outputs found
Order-Restricted Inference for Generalized Inverted Exponential Distribution under Balanced Joint Progressive Type-II Censored Data and Its Application on the Breaking Strength of Jute Fibers
This article considers a new improved balanced joint progressive type-II censoring scheme based on two different populations, where the lifetime distributions of two populations follow the generalized inverted exponential distribution with different shape parameters but a common scale parameter. The maximum likelihood estimates of all unknown parameters are obtained and their asymptotic confidence intervals are constructed by the observed Fisher information matrix. Furthermore, the existence and uniqueness of solutions are proved. In the Bayesian framework, the common scale parameter follows an independent Gamma prior and the different shape parameters jointly follow a Beta-Gamma prior. Based on whether the order restriction is imposed on the shape parameters, the Bayesian estimates of all parameters concerning the squared error loss function along with the associated highest posterior density credible intervals are derived by using the importance sampling technique. Then, we use Monte Carlo simulations to study the performance of the various estimators and a real dataset is discussed to illustrate all of the estimation techniques. Finally, we seek an optimum censoring scheme through different optimality criteria
Relationship between PaO2/FiO2 and delirium in intensive care: A cross-sectional study
Background: To investigate the relationship between partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FiO2) and the probability of delirium in intensive care units (ICUs). Methods: The investigation was a cross-sectional study that involved the collection of data from patients admitted to the Xiang Ya Hospital Cardiothoracic Surgical Care Unit and Comprehensive Intensive Care Unit from 01 September 2016 to 10 December 2016. Delirium was diagnosed using the simplified version of the Chinese Confusion Assessment Method (CAM) for the ICU. Demographic and medical data were obtained within 24 h of each patient admitted in the ICU. The PaO2/FiO2 of each patient was recorded 24 h after admission in the ICU. The patients were divided into three groups according to PaO2/FiO2 data : normal (PaO2/FiO2 ≥300 mmHg), slightly low (200 ≥PaO2/FiO2 <300 mmHg), and severely low (PaO2/FiO2 <200 mmHg). Baseline characteristics were compared in the three groups. Results of the unadjusted model, minimally adjusted model, and fully adjusted model are presented. Results: A total of 403 participants were included in the study, of which 184 (45.7%) developed delirium. Age (P <0.001), Sequential Organ Failure Assessment (SOFA) score (P <0.001), Acute Physiology and Chronic Health Evaluation (APACHE) II score (P <0.001), mechanical ventilation time (P <0.001), history of hypertension (P=0.040), heart disease (P=0.040), sedation (P=0.001), and PaO2/FiO2 (P=0.006) were significantly associated with delirium in univariate analysis. Multivariate regression analysis models were used to further analyze the associations between PaO2/FiO2 and delirium. In the crude model, for 1 standard deviation (SD) increase in PaO2/FiO2, the odds ratio (OR) of delirium was 0.8 (95% confidence interval [CI]: 0.6–0.9), but there was no significant correlation in the fully adjusted model. There was a non-linear relationship between the PaO2/FiO2 and delirium in a generalized additive model. A two-piecewise linear regression model was used to calculate a PaO2/FiO2 threshold of 243 mmHg. On the left side of the threshold, the OR was 0.9 and the 95% CI was 0.9–1.0 (P=0.013) when PaO2/FiO2 increased by 1 SD. Conclusions: PaO2/FiO2 was negatively associated with delirium when PaO2/FiO2 was below the identified threshold. As a readily available laboratory indicator, PaO2/FiO2 has potential value in the clinical evaluation of risk of delirium in ICU patients
Key Technology of Pilot’s Cognitive Decision-making Capacity Evaluation Based on Distributed Computing
To provide effective technological means for evaluation of the pilot’s information processing capacity for combat missions, tactical capability, command capability and cognitive decision-making capacity to compensate for the deficiency in the paper and pencil test, psychological dynamoscopy and other technological means used for traditional pilot’s cognitive decision-making capacity evaluation. Based on distributed computing technology, build a topological structure of the evaluation system, design a background of typical combat mission, and simulate combat control interface and process; based on software engineering, establish records, manage and analyze the evaluation technology of process data. The result of this study is that a scientific method and objective measurement means need to be provided for “real” evaluation of the pilot’s cognitive decision-making capacity
Key Technology of Pilot’s Cognitive Decision-making Capacity Evaluation Based on Distributed Computing
To provide effective technological means for evaluation of the pilot’s information processing capacity for combat missions, tactical capability, command capability and cognitive decision-making capacity to compensate for the deficiency in the paper and pencil test, psychological dynamoscopy and other technological means used for traditional pilot’s cognitive decision-making capacity evaluation. Based on distributed computing technology, build a topological structure of the evaluation system, design a background of typical combat mission, and simulate combat control interface and process; based on software engineering, establish records, manage and analyze the evaluation technology of process data. The result of this study is that a scientific method and objective measurement means need to be provided for “real” evaluation of the pilot’s cognitive decision-making capacity
Key Technology of Pilot’s Cognitive Decision-making Capacity Evaluation Based on Distributed Computing
To provide effective technological means for evaluation of the pilot’s information processing capacity for combat missions, tactical capability, command capability and cognitive decision-making capacity to compensate for the deficiency in the paper and pencil test, psychological dynamoscopy and other technological means used for traditional pilot’s cognitive decision-making capacity evaluation. Based on distributed computing technology, build a topological structure of the evaluation system, design a background of typical combat mission, and simulate combat control interface and process; based on software engineering, establish records, manage and analyze the evaluation technology of process data. The result of this study is that a scientific method and objective measurement means need to be provided for “real” evaluation of the pilot’s cognitive decision-making capacity
Plasma-induced on-surface sulfur vacancies in NiCo2S4 enhance the energy storage performance of supercapatteries
Vacancies have received considerable attention in energy storage materials since they are able to generate more active defects, leading to enhanced conductivity and thus higher capability. Here, we provide a facile strategy to rapidly achieve sufficient sulphur vacancies, lattice distortion and changed charge-states of Ni/Co on the material surface layer in NiCo2S4via low-temperature atmospheric pressure plasma. Both experimental results and DFT calculations have demonstrated that enhanced performances can be obtained with different amounts of sulphur vacancies (S-vacancies), with optimal performance obtained at 30% S-vacancy. Moreover, the same trend of enhanced energy storage performance effects is found in comparison groups of varied Ni/Co atomic ratios (1 : 1, 2 : 1, 1 : 4, 4 : 1), suggesting the serviceability of this facile strategy, which only requires 30 seconds of processing. This paves a path towards high-performance supercapatteries using the simple plasma-based method
Activated mutant forms of PIK3CA cooperate with RasV12 or c-Met to induce liver tumour formation in mice via AKT2/mTORC1 cascade
Background & AimsActivating mutations of PIK3CA occur in various tumour types, including human hepatocellular carcinoma. The mechanisms whereby PIK3CA contributes to hepatocarcinogenesis remain poorly understood. MethodsPIK3CA mutants H1047R or E545K were hydrodynamically transfected, either alone or in combination with NRasV12 or c-Met genes, in the mouse liver. ResultsOverexpression of H1047R or E545K alone was able to induce AKT/mTOR signalling in the mouse liver, leading to hepatic steatosis. However, none of the mice developed liver tumours over long term. In contrast, H1047R or E545K cooperated with NRasV12 or c-Met to rapidly induce liver tumour formation in mice. At the molecular level, all the tumour nodules displayed activation of AKT/mTOR and Ras/MAPK cascades. Ablation of AKT2 significantly inhibited hepatic steatosis induced by H1047R or E545K and carcinogenesis induced by H1047R/c-Met or E545K/c-Met. Furthermore, tumourigenesis induced by H1047R/c-Met was abolished in conditional Raptor knockout mice. ConclusionsBoth H1047R and E545K are able to activate the AKT/mTOR pathway. An intact AKT2/mTOR complex 1 cascade is required for tumourigenesis induced by H1047R/c-Met or E545K/c-Met in the liver
Crystal Structure of Human CD47 in Complex with Engineered SIRPα.D1(N80A)
Background: Targeting the CD47/SIRPα signaling pathway represents a novel approach to enhance anti-tumor immunity. However, the crystal structure of the CD47/SIRPα has not been fully studied. This study aims to analyze the structure interface of the complex of CD47 and IMM01, a novel recombinant SIRPα-Fc fusion protein. Methods: IMM01-Fab/CD47 complex was crystalized, and diffraction images were collected. The complex structure was determined by molecular replacement using the program PHASER with the CD47-SIRPαv2 structure (PDB code 2JJT) as a search model. The model was manually built using the COOT program and refined using TLS parameters in REFMAC from the CCP4 program suite. Results: Crystallization and structure determination analysis of the interface of IMM01/CD47 structure demonstrated CD47 surface buried by IMM01. Comparison with the literature structure (PDB ID 2JJT) showed that the interactions of IMM01/CD47 structure are the same. All the hydrogen bonds that appear in the literature structure are also present in the IMM01/CD47 structure. These common hydrogen bonds are stable under different crystal packing styles, suggesting that these hydrogen bonds are important for protein binding. In the structure of human CD47 in complex with human SIRPα, except SER66, the amino acids that form hydrogen bonds are all conserved. Furthermore, comparing with the structure of PDB ID 2JJT, the salt bridge interaction from IMM01/CD47 structure are very similar, except the salt bridge bond between LYS53 in IMM01 and GLU106 in CD47, which only occurs between the B and D chains. However, as the side chain conformation of LYS53 in chain A is slightly different, the salt bridge bond is absent between the A and C chains. At this site between chain A and chain C, there are a salt bridge bond between LYS53 (A) and GLU104 (C) and a salt bridge bond between HIS56 (A) and GLU106 (C) instead. According to the sequence alignment results of SIRPα, SIRPβ and SIRPγ in the literature of PDB ID 2JJT, except ASP100, the amino acids that form common salt bridge bonds are all conserved. Conclusion: Our data demonstrated crystal structure of the IMM01/CD47 complex and provides a structural basis for the structural binding interface and future clinical applications
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Prediction and evaluation of high-risk patients with primary biliary cholangitis receiving ursodeoxycholic acid therapy: an early criterion
Background and aimsCurrent treatment guidelines recommend ursodeoxycholic acid (UDCA) as the first-line treatment for new-diagnosed primary biliary cholangitis (PBC) patients. However, up to 40% patients are insensitive to UDCA monotherapy, and evaluation of UDCA response at 12 months may result in long period of ineffective treatment. We aimed to develop a new criterion to reliably identify non-response patients much earlier.MethodsFive hundred sixty-nine patients with an average of 59 months (Median: 53; IQR:32-79) follow-up periods were randomly divided into either the training (70%) or the validation cohort (30%). The efficiency of different combinations of total bilirubin (TBIL), alkaline phosphatase (ALP), and aspartate aminotransferase (AST) threshold values to predict outcomes was assessed at 1, 3 or 6 month after the initiation of UDCA therapy. The endpoints were defined as adverse outcomes, including liver-related death, liver transplantation and complications of cirrhosis. Adverse outcome-free survival was compared using various published criteria and a proposed new criterion.ResultsA new criterion of evaluating UDCA responses at 1 month was established as: ALP ≤ 2.5 × upper limit of normal (ULN) and AST ≤ 2 × ULN, and TBIL ≤ 1 × ULN (Xi'an criterion). The 5 year adverse outcome-free survival rate of UDCA responders, defined by Xi'an criterion, was 97%, which was significantly higher than that of those non-responders (64%). An accurate distinguishing high-risk patients' capacity of Xi'an criterion was confirmed in both early and late-stage PBC.ConclusionsXi'an criterion has a similar or even higher ability to distinguish high-risk PBC patients than other published criteria. Xi'an criterion can facilitate early identification of patients requiring new therapeutic approaches