A Loan-level Residential Mortgage Backed Security Pricing Model: Are CAP CRA Loans Profit-Making for the Secondary Market?

This paper develops an industry comparable loan-level residential mortgage-backed security pricing model. It can be used to design hedging strategies for mortgage portfolio's interest rate risk, and price the cost of guaranteeing RMBS default risk. The loan-level pricing model is designed to address most of the problems with the Government-Sponsored Enterprises' (GSEs') current risk management models that were outlined in the Federal Housing and Finance Administration's 2009 report to Congress. The loan-level pricing model in this paper is able to automatically translate into RMBS prices the slight monthly changes in individual borrowers' prepayment and default risks due to borrower and loan characteristics, macroeconomic conditions, house price changes, and term structure movements. The loan-level model is especially useful for managing low-to-moderate income (LMI) mortgages, which are highly leveraged assets. Applying the loan-level pricing model to the Community Advantage Program (CAP) dataset yields the result that most (i.e. 65% of the purchased CAP loans) of the Community Reinvestment Act (CRA) mortgages in CAP have been profit-making (i.e. positive Option-Adjusted Spreads OAS) for the secondary market, given the market prices Fannie Mae paid. Moreover, the results suggest that the conventional indicators, such as race, income, credit score and loan-to-value at origination, are not reliable in determinants of the mortgage yield. Therefore, avoiding and discriminating against LMI mortgage pools are not rational. The identification of responsible LMI borrowers or pools and adequate risk based pricing require that the loan-level pricing model be run on each mortgage portfolio. Finally, the loan-level pricing model can help to address one challenge in the overhaul of mortgage finance system pointed out by Geithner, namely pricing the cost of a government guarantee of RMBS default risk. In particular, the expected cost for guaranteeing the default risk of a loan can be calculated as the difference in the OAS between 100% recovery and recovery at the current house price. In short, the loan-level pricing model developed may help the federal government to better meet the financial needs of responsible LMI borrowers, while maintaining the sustainability and soundness of the GSEs

In Situ Real-Time Chemiluminescence Imaging of Reactive Oxygen Species Formation from Cardiomyocytes

We have applied the highly sensitive chemiluminescence (CL) imaging technique to investigate the in situ ROS formation in cultured monolayers of rat H9c2 cardiomyocytes. Photon emission was detected via an innovative imaging system after incubation of H9c2 cells in culture with luminol and horseradish peroxidase (HRP), suggesting constitutive formation of ROS by the cardiomyocytes. Addition of benzo(a)pyrene-1,6-quinone (BPQ) to cultured H9c2 cells resulted in a 4-5-fold increase in the formation of ROS, as detected by the CL imaging. Both constitutive and BPQ-stimulated CL responses in cultured H9c2 cells were sustained for up to 1 hour. The CL responses were completely abolished in the presence of superoxide dismutase and catalase, suggesting the primary involvement of superoxide and hydrogen peroxide (H2O2). In contrast to BPQ-mediated redox cycling, blockage of mitochondrial electron transport chain by either antimycin A or rotenone exerted marginal effects on the ROS formation by cultured H9c2 cells. Upregulation of cellular antioxidants for detoxifying both superoxide and H2O2 by 3H-1,2-dithiole-3-thione resulted in marked inhibition of both constitutive and BPQ-augmented ROS formation in cultured H9c2 cells. Taken together, we demonstrate the sensitive detection of ROS by CL imaging in cultured cardiomyocytes

The Anzhen Risk Scoring System for Acute Type A Aortic Dissection: A Prospective Observational Study Protocol

Introduction: Acute type A aortic dissection (ATAAD) is a catastrophic disease with fatal outcomes. Malperfusion syndrome (MPS) is a serious complication of ATAAD, with an incidence of 20–40%. Many studies have shown that MPS is the main risk factor for poor ATAAD prognosis. However, a risk scoring system for ATAAD based on MPS is lacking. Here, we designed a risk scoring system for ATAAD to assess mortality through quantitative assessment of relevant organ malperfusion and subsequently develop rational treatment strategies.Methods and analysis: This was a prospective observational study. Patients’ perioperative clinical data were collected to establish a database of ATAAD (N≥3000) and determine whether these patients had malperfusion complications. The Anzhen risk scoring system was established on the basis of organ malperfusion by using a random forest survival model and a logistics model. The better method was then chosen to establish a revised risk scoring system.Ethics and dissemination: This study received ethical approval from the Ethics Committees of Beijing Anzhen Hospital, Capital Medical University (KS2019034-1). Patient consent was waived because biological samples were not collected, and no patient rights were violated. Findings will be disseminated at scientific conferences and in peer-reviewed publications

Design for choice-making: incorporating design research and behavioural economics into healthcare interventions in China

Despite its interdisciplinary nature and capacity to solve wicked societal problems, design research faces gaps in conceptual scholarship and theory-driven methodologies. Influential theories, such as Heskett’s Value Creation Theory, have delved into the nexus of design and economics, underscoring design’s role in economic value creation. Nonetheless, there appears to be a deficiency in theory building at the intersection of design and economics, especially regarding the broader impacts of design. Such an endeavour demands a robust theoretical foundation, advocating and demonstrating design’s growing role in shaping societal interventions and policymaking.Introducing the concept of ‘Design for Choice-Making’ has a potential to bridge this intersection between design and economics. Choice-making, being integral to economics, reflects individuals’ decisions within constraints and biases. Yet, its representation in design, despite having roots in the discipline, remains scarce. This research explores a behavioural and inclusive approach to choice-making, embedding it within a designerly way of thinking and doing. By doing so, it outlines the Inclusive Behavioural Design process to incorporate design research and Behavioural Economics insights into designing interventions. To examine and evaluate the effectiveness of the proposed concept and process model, empirical studies were conducted in the context of rural health in China. The empirical research began by expanding the context to systematically map the health choices available for rural residents and the contextual and behavioural influences. Employing the behavioural model of choice, which includes concepts such as psychological scarcity, present bias, and risk aversion, through an economics perspective, led to the reframing of problems and the generation of hypotheses. Subsequently, a field experiment (with 479 participants) and a quasi-experiment (with 677 participants) were carried out to test these hypotheses in rural areas and urban environments among lower and higher income groups, respectively. Merging these contextualised insights with evidence from experiments laid a solid foundation for the development of inclusive, context-appropriate interventions, classified as choice architectures and choice infrastructures. The empirical studies confirmed the effectiveness of the concept and the process model, while also identifying challenges and discrepancies that need future refinement.This thesis provides a fresh theoretical perspective on the study of choice-making in design, potentially paving the way for applying the behavioural model of choice-making in economics into design research. Furthermore, it brings an inclusive perspective to designing interventions. The thesis also offers recommendations for health intervention design, with a focus on improving choice-making behaviours and outcomes among lower income groups.</p

Gas Pipeline Leakage Detection Method Based on IUPLCD and GS-TBSVM

To improve the identification accuracy of gas pipeline leakage and reduce the false alarm rate, a pipeline leakage detection method based on improved uniform-phase local characteristic-scale decomposition (IUPLCD) and grid search algorithm-optimized twin-bounded support vector machine (GS-TBSVM) was proposed. First, the signal was decomposed into several intrinsic scale components (ISC) by the UPLCD algorithm. Then, the signal reconstruction process of UPLCD was optimized and improved according to the energy and standard deviation of the amplitude of each ISC, the ISC components dominated by the signal were selected for signal reconstruction, and the denoised signal was obtained. Finally, the TBSVM was optimized using a grid search algorithm, and a GS-TBSVM model for pipeline leakage identification was constructed. The input of the GS-TBSVM model was the data processed by the IUPLCD algorithm, and the output was the real-time working conditions of the gas pipeline. The experimental results show that IUPLCD can effectively filter the noise in the signal and GS-TBSVM can accurately judge the working conditions of the gas pipeline, with a maximum identification accuracy of 98.4%

Relationship Between Enterprise Talent Management and Performance Based on the Structural Equation Model Method

This article uses SPSS19.0 and AMOS21.0 statistical software to explore the relationship between corporate talent management and corporate performance. We use the structural equation model to quantitatively analyze the human resource management factors that affect logistics performance. Research shows that intellectual capital has a significant positive effect on enterprise innovation performance. The value proposition of employee training to customers and good customer service have an overall positive economic effect. Human capital plays a significant role in driving innovation performance only in the more mature stage of enterprise development

High-Throughput Phenotyping Analysis of Potted Soybean Plants Using Colorized Depth Images Based on A Proximal Platform

Canopy color and structure can strongly reflect plant functions. Color characteristics and plant height as well as canopy breadth are important aspects of the canopy phenotype of soybean plants. High-throughput phenotyping systems with imaging capabilities providing color and depth information can rapidly acquire data of soybean plants, making it possible to quantify and monitor soybean canopy development. The goal of this study was to develop a 3D imaging approach to quantitatively analyze soybean canopy development under natural light conditions. Thus, a Kinect sensor-based high-throughput phenotyping (HTP) platform was developed for soybean plant phenotyping. To calculate color traits accurately, the distortion phenomenon of color images was first registered in accordance with the principle of three primary colors and color constancy. Then, the registered color images were applied to depth images for the reconstruction of the colorized three-dimensional canopy structure. Furthermore, the 3D point cloud of soybean canopies was extracted from the background according to adjusted threshold, and each area of individual potted soybean plants in the depth images was segmented for the calculation of phenotypic traits. Finally, color indices, plant height and canopy breadth were assessed based on 3D point cloud of soybean canopies. The results showed that the maximum error of registration for the R, G, and B bands in the dataset was 1.26%, 1.09%, and 0.75%, respectively. Correlation analysis between the sensors and manual measurements yielded R2 values of 0.99, 0.89, and 0.89 for plant height, canopy breadth in the west-east (W&#8722;E) direction, and canopy breadth in the north-south (N&#8722;S) direction, and R2 values of 0.82, 0.79, and 0.80 for color indices h, s, and i, respectively. Given these results, the proposed approaches provide new opportunities for the identification of the quantitative traits that control canopy structure in genetic/genomic studies or for soybean yield prediction in breeding programs

A Facile Flow-Casting Production of Bioactive Glass Coatings on Porous Titanium for Bone Tissue Engineering

Additive manufacturing enabled the fabrication of porous titanium (PT) with customized porosity and mechanical properties. However, functionalization of PT surfaces with bioactive coatings is being challenged due to sophisticated geometry and highly porous structure. In this study, a facile flow-casting technique was developed to produce homogeneous 45S5 bioactive glass (BG) coatings on the entire surface of PT. The coating weight as a function of BG concentration in a BG-PVA slurry was investigated to achieve controllable coating yield without blocking macropore structure. The annealing-treated BG coating not only exhibited compact adhesion confirmed by qualitative sonication treatment, but also enhanced the mechanical properties of PT scaffolds. Moreover, in-vitro assessments of BG-coated PT cultured with MC3T3-E1 cells was carried out having in mind their potential as bioactive bone implants. The experimental results in this study offer a simple and versatile approach for the bio-functionalization of PT and other porous biomedical devices