2,980 research outputs found
Essays on macroeconomics and forecasting
This dissertation consists of three essays. Chapter II uses the method of structural
factor analysis to study the effects of monetary policy on key macroeconomic variables
in a data rich environment. I propose two structural factor models. One is the structural
factor augmented vector autoregressive (SFAVAR) model and the other is the structural
factor vector autoregressive (SFVAR) model. Compared to the traditional vector
autogression (VAR) model, both models incorporate far more information from
hundreds of data series, series that can be and are monitored by the Central Bank.
Moreover, the factors used are structurally meaningful, a feature that adds to the
understanding of the âÂÂblack boxâ of the monetary transmission mechanism. Both models
generate qualitatively reasonable impulse response functions. Using the SFVAR model,
both the âÂÂprice puzzleâ and the âÂÂliquidity puzzleâ are eliminated.
Chapter III employs the method of structural factor analysis to conduct a
forecasting exercise in a data rich environment. I simulate out-of-sample real time
forecasting using a structural dynamic factor forecasting model and its variations. I use
several structural factors to summarize the information from a large set of candidate
explanatory variables. Compared to Stock and Watson (2002)âÂÂs models, the models proposed in this chapter can further allow me to select the factors structurally for each
variable to be forecasted. I find advantages to using the structural dynamic factor
forecasting models compared to alternatives that include univariate autoregression (AR)
model, the VAR model and Stock and WatsonâÂÂs (2002) models, especially when
forecasting real variables.
In chapter IV, we measure U.S. technology shocks by implementing a dual
approach, which is based on more reliable price data instead of aggregate quantity data.
By doing so, we find the relative volatility of technology shocks and the correlation
between output fluctuation and technology shocks to be much smaller than those
revealed in most real-business-cycle (RBC) studies. Our results support the findings of
Burnside, Eichenbaum and Rebelo (1996), who showed that the correlation between
technology shocks and output is exaggerated in the RBC literature. This suggests that
one should examine other sources of fluctuations for a better understanding of the
business cycle phenomena
Research on Marine Pollution Problems and Solutions in China from the Perspective of Marine Tourism
Based on the perspective of marine tourism, this paper integrates various types of marine pollution, and puts forward high-quality development solutions and future extension direction of marine tourism. Through the research, it is found that the main culprits of marine pollution mainly include the following seven points: human activities produce garbage; white pollution; ship pollution; exploration of marine oil and gas resources and mineral pollution;Â land reclamation;Â pollution in mariculture industry and new estrogen pollution. The causes of marine pollution and countermeasures are discussed
Multiple Data-Dependent Kernel Fisher Discriminant Analysis for Face Recognition
Kernel Fisher discriminant analysis (KFDA) method has demonstrated its success in extracting facial features for face recognition. Compared to linear techniques, it can better describe the complex and nonlinear variations of face images. However, a single kernel is not always suitable for the applications of face recognition which contain data from multiple, heterogeneous sources, such as face images under huge variations of pose, illumination, and facial expression. To improve the performance of KFDA in face recognition, a novel algorithm named multiple data-dependent kernel Fisher discriminant analysis (MDKFDA) is proposed in this paper. The constructed multiple data-dependent kernel (MDK) is a combination of several base kernels with a data-dependent kernel constraint on their weights. By solving the optimization equation based on Fisher criterion and maximizing the margin criterion, the parameter optimization of data-dependent kernel and multiple base kernels is achieved. Experimental results on the three face databases validate the effectiveness of the proposed algorithm
Yielding and hardening of flexible fiber packings during triaxial compression
This paper examines the mechanical response of flexible fiber packings
subject to triaxial compression. Short fibers yield in a manner similar to
typical granular materials in which the deviatoric stress remains nearly
constant with increasing strain after reaching a peak value. Interestingly,
long fibers exhibit a hardening behavior, where the stress increases rapidly
with increasing strain at large strains and the packing density continuously
increases. Phase diagrams for classifying the bulk mechanical response as
yielding, hardening, or a transition regime are generated as a function of the
fiber aspect ratio, fiber-fiber friction coefficient, and confining pressure.
Large fiber aspect ratio, large fiber-fiber friction coefficient, and large
confining pressure promote hardening behavior. The hardening packings can
support much larger loads than the yielding packings contributing to the
stability and consolidation of the granular structure, but larger internal
axial forces occur within fibers.Comment: 14 pages, 4 figure
Nutrition, Histone Epigenetic Marks, and Disease
The dietary intake of essential nutrients and bioactive food compounds is a process that occurs on a daily basis for the entire life span. Therefore, your diet has a great potential to cause changes in the epigenome. Known histone modifications include acetylation, methylation, biotinylation, poly(ADP-ribosylation), ubiquitination, and sumoylation. Some of these modifications depend directly on dietary nutrients. For other modifications, bioactive dietary compounds may alter the activities of enzymes that establish or remove histone marks, thereby altering the epigenome. This chapter provides an overview of diet-dependent epigenomic marks in histones and their links with human health
KNOWLEDGE MANAGEMENT CAPABILITY AND FIRM PERFORMANCE: THE MEDIATING ROLE OF ORGANIZATIONAL AGILITY
Implementing knowledge management capability (KMC) effectively is becoming an important strategic issue for organizational success. However, our understanding about the underlying mechanism of KMC on firm performance is still limited. Based on the dynamic capabilities perspective, this study tries to explore how KMC (i.e., exploration KMC and exploitation KMC) affects firm performance through the mediating role of operational adjustment agility and market capitalizing agility. Survey data from 211 firms indicate that both operational adjustment agility and market capitalizing agility can fully mediate the influence of KMC on firm performance. In addition, the relationship intensions of these two KMC on organizational agility are distinguishing. We conclude with implications and limitations for future research
Nutrition, Histone Epigenetic Marks, and Disease
The dietary intake of essential nutrients and bioactive food compounds is a process that occurs on a daily basis for the entire life span. Therefore, your diet has a great potential to cause changes in the epigenome. Known histone modifications include acetylation, methylation, biotinylation, poly(ADP-ribosylation), ubiquitination, and sumoylation. Some of these modifications depend directly on dietary nutrients. For other modifications, bioactive dietary compounds may alter the activities of enzymes that establish or remove histone marks, thereby altering the epigenome. This chapter provides an overview of diet-dependent epigenomic marks in histones and their links with human health
Increased expression of TAZ and associated upregulation of PD-L1 in cervical cancer
Background As an important component of the Hippo pathway, WW domain-containing transcription regulator 1 (TAZ), is a transcriptional coactivator that is responsible for the progression of various types of cancers. Programmed cell death protein 1 (PD-1) receptors in activated T cells and their ligand programming death force 1 (PD-L1) are the main checkpoint signals that control T cell activity. Studies have shown high levels of PD-L1 in various cancers and that PD-L1/PD-1 signals to evade T-cell immunity. Recent data have demonstrated that TAZ can regulate the characteristics of cancer cells via PD-L1. Cervical cancer is a common gynecological disease worldwide. In this study, we attempted to evaluate the effects of TAZ and PD-L1 on cervical cancer.
Methods Hela cervical cancer cells were transfected with TAZ plasmid or TAZ siRNA or PD-L1 siRNA by using Lipofectamine 2000. The relationship between TAZ and PD-L1 in cervical cancer cells was determined by qRT-PCR and western blotting. The functional roles of TAZ were confirmed via CCK-8, Transwell and flow cytometry assays. Western blotting was utilized to observe the expression of BCL-2 and Caspase-3. The clinicopathological correlation of TAZ and PD-L1 was evaluated via relevant databases.
Result TAZ is upregulated in cervical cancer and induces the growth and metastasis of cervical cancer cells by targeting PD-L1and inhibiting the ratio of apoptotic of cancer cells. High TAZ and PD-L1 expression was observed in different stage, grade, histological patterns, and ages of cervical cancer groups compared with normal cervix groups. Furthermore, high TAZ expression was positively correlated with the infiltration levels of immune cells and the expression of PD-L1
- …