30 research outputs found
SAM: Self-adapting Mixture Prior to Dynamically Borrow Information from Historical Data in Clinical Trials
Mixture priors provide an intuitive way to incorporate historical data while
accounting for potential prior-data conflict by combining an informative prior
with a non-informative prior. However, pre-specifying the mixing weight for
each component remains a crucial challenge. Ideally, the mixing weight should
reflect the degree of prior-data conflict, which is often unknown beforehand,
posing a significant obstacle to the application and acceptance of mixture
priors. To address this challenge, we introduce self-adapting mixture (SAM)
priors that determine the mixing weight using likelihood ratio test statistics
or Bayes factor. SAM priors are data-driven and self-adapting, favoring the
informative (non-informative) prior component when there is little
(substantial) evidence of prior-data conflict. Consequently, SAM priors achieve
dynamic information borrowing. We demonstrate that SAM priors exhibit desirable
properties in both finite and large samples and achieve information-borrowing
consistency. Moreover, SAM priors are easy to compute, data-driven, and
calibration-free, mitigating the risk of data dredging. Numerical studies show
that SAM priors outperform existing methods in adopting prior-data conflicts
effectively. We developed an R package and web application that are freely
available to facilitate the use of SAM priors
Key Technology of Construction Process Control of Guide Frame Platform Suction Bucket Foundation
[Introduction] The present, design and construction technology of suction bucket foundation is not mature, and there is lack of the normative guidance documents, the special research on the key technology of the construction process control of the suction bucket was implemented. [Method] Taking an offshore wind farm project as the background, based on the measured data of orientation platform foundations, statistical analysis, data mining, process back in the inversion method and technology was used. [Result] The constitution and function of the complete set of installation equipment of suction bucket foundation and the intelligent and digital control system are described in detail. The control parameters and control standards in the construction process of suction bucket foundation of guide frame platform are discussed. The feasibility analysis and calculation method and parameter value method of suction bucket penetration/jacking are summarized. The key points and control methods of each link in the whole process of suction bucket from penetration to jacking and recovery are put forward. [Conclusion] Finally, according to the measured construction data of seven four-pile guide frame platform suction bucket foundation, the variation characteristics of control parameters and the control effect during the construction of suction bucket foundation are illustrated. It can be used for reference in the design and construction of similar suction bucket platform foundation
Additive and interactive associations of Environmental and Sociodemographic Factors With the Genotypes of Three Glutathione S-Transferase Genes in Relation to the Blood arsenic Concentrations of Children in Jamaica
Arsenic (As) is a metalloid that has been classified as a xenobiotic with toxic effects on human beings, especially on children. Since the soil in Jamaica contains As, dietary intake is considered the main source of As exposure in Jamaicans. In addition, glutathione S-transferase (GST) genes, includin
A Fuzzy Comprehensive Evaluation Method Based on AHP and Entropy for a Landslide Susceptibility Map
Landslides are a common type of natural disaster in mountainous areas. As a result of the comprehensive influences of geology, geomorphology and climatic conditions, the susceptibility to landslide hazards in mountainous areas shows obvious regionalism. The evaluation of regional landslide susceptibility can help reduce the risk to the lives of mountain residents. In this paper, the Shannon entropy theory, a fuzzy comprehensive method and an analytic hierarchy process (AHP) have been used to demonstrate a variable type of weighting for landslide susceptibility evaluation modeling, combining subjective and objective weights. Further, based on a single factor sensitivity analysis, we established a strict criterion for landslide susceptibility assessments. Eight influencing factors have been selected for the study of Zhen’an County, Shan’xi Province: the lithology, relief amplitude, slope, aspect, slope morphology, altitude, annual mean rainfall and distance to the river. In order to verify the advantages of the proposed method, the landslide index, prediction accuracy P, the R-index and the area under the curve were used in this paper. The results show that the proposed model of landslide hazard susceptibility can help to produce more objective and accurate landslide susceptibility maps, which not only take advantage of the information from the original data, but also reflect an expert’s knowledge and the opinions of decision-makers
A Fuzzy Comprehensive Evaluation Method Based on AHP and Entropy for a Landslide Susceptibility Map
Stromal cells in the tumor microenvironment: accomplices of tumor progression?
Abstract The tumor microenvironment (TME) is made up of cells and extracellular matrix (non-cellular component), and cellular components include cancer cells and non-malignant cells such as immune cells and stromal cells. These three types of cells establish complex signals in the body and further influence tumor genesis, development, metastasis and participate in resistance to anti-tumor therapy. It has attracted scholars to study immune cells in TME due to the significant efficacy of immune checkpoint inhibitors (ICI) and chimeric antigen receptor T (CAR-T) in solid tumors and hematologic tumors. After more than 10 years of efforts, the role of immune cells in TME and the strategy of treating tumors based on immune cells have developed rapidly. Moreover, ICI have been recommended by guidelines as first- or second-line treatment strategies in a variety of tumors. At the same time, stromal cells is another major class of cellular components in TME, which also play a very important role in tumor metabolism, growth, metastasis, immune evasion and treatment resistance. Stromal cells can be recruited from neighboring non-cancerous host stromal cells and can also be formed by transdifferentiation from stromal cells to stromal cells or from tumor cells to stromal cells. Moreover, they participate in tumor genesis, development and drug resistance by secreting various factors and exosomes, participating in tumor angiogenesis and tumor metabolism, regulating the immune response in TME and extracellular matrix. However, with the deepening understanding of stromal cells, people found that stromal cells not only have the effect of promoting tumor but also can inhibit tumor in some cases. In this review, we will introduce the origin of stromal cells in TME as well as the role and specific mechanism of stromal cells in tumorigenesis and tumor development and strategies for treatment of tumors based on stromal cells. We will focus on tumor-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), tumor-associated adipocytes (CAAs), tumor endothelial cells (TECs) and pericytes (PCs) in stromal cells
Interactions between Environmental Factors and Glutathione S-Transferase (GST) Genes with Respect to Detectable Blood Aluminum Concentrations in Jamaican Children
Aluminum (Al) is a metallic toxicant at high concentrations following natural or unnatural exposures. Dietary intake is considered as the main source of aluminum exposure in children. We used data from 366 typically developing (TD) children (ages 2–8 years) who participated as controls in an age- and sex-matched case–control study in Jamaica. We investigated additive and interactive associations among environmental factors and children’s genotypes for glutathione S-transferase (GST) genes (GSTT1, GSTM1, GSTP1), in relation to having a detectable blood aluminum concentration (BAlC) of >5.0 μg/L, using multivariable logistic regression models. Findings from interactive models revealed that the odds of having a detectable BAlC was significantly higher among children who ate string beans (p ≤ 0.01), whereas about 40% lower odds of having a detectable BAlC was observed in children with higher parental education level, (p = 0.02). A significant interaction between consumption of saltwater fish and GSTP1 in relation to having a detectable BAlC using either co-dominant or dominant genetic models (overall interaction p = 0.02 for both models) indicated that consumption of saltwater fish was associated with higher odds of having a detectable BAlC only among children with the GSTP1 Ile105Val Ile/Ile genotype using either co-dominant or dominant models [OR (95% CI) = 2.73 (1.07, 6.96), p = 0.04; and OR (95% CI) = 2.74 (1.08, 6.99), p = 0.03]. Since this is the first study from Jamaica that reports such findings, replication in other populations is warranted