117 research outputs found
A Meta-Analysis of the Relationship Between Corporate Social Responsibility and Consumer Response in the Chinese Context
Consumers’ attitudes toward corporate social responsibility (CSR) and their response levels can significantly affect a firm’s behaviors. Based on 61 research papers addressing CSR responses to consumers in China, this study conducted a meta-analysis on three variables: CSR type, CSR characteristics, and CSR publicity behavior, which impact the CSR relationship. The following conclusions are drawn: Corporate social responsibility (encompassing private and public moral dimensions) elicits a positive consumer response, with private moral behavior having a greater positive effect compared to public moral behavior. The four dimensions of CSR characteristics (CSR commitment, CSR level, CSR correlation, and CSR timing) all lead to positive consumer responses. Positive consumer responses also arise from CSR publicity behavior, including publicity initiative and publicity intensity. Additionally, product type, sample time, and sample source have significant moderating effects on these relationships
Common Bubble Detection in Large Dimensional Financial Systems
Price bubbles in multiple assets are sometimes nearly coincident in occurrence. Such near-coincidence is strongly suggestive of co-movement in the associated asset prices and likely driven by certain factors that are latent in the financial or economic system with common effects across several markets. Can we detect the presence of such common factors at the early stages of their emergence? To answer this question, we build a factor model that includes I(1), mildly explosive, and stationary factors to capture normal, exuberant, and collapsing phases in such phenomena. The I(1) factor models the primary driving force of market fundamentals. The explosive and stationary factors model latent forces that underlie the formation and destruction of asset price bubbles, which typically exist only for subperiods of the sample. The paper provides an algorithm for testing the presence of and date-stamping the origination and termination of price bubbles determined by latent factors in a large-dimensional system embodying many markets. Asymptotics of the bubble test statistic are given under the null of no common bubbles and the alternative of a common bubble across these markets. We prove consistency of a factor bubble detection process for the origination and termination dates of the common bubble. Simulations show good finite sample performance of the testing algorithm in terms of its successful detection rates. Our methods are applied to real estate markets covering 89 major cities in China over the period January 2003 to March 2013. Results suggest the presence of three common bubble episodes in what are known as China’s Tier 1 and Tier 2 cities over the sample period. There appears to be little evidence of a common bubble in Tier 3 cities
Green Holographic MIMO Communications With A Few Transmit Radio Frequency Chains
Holographic multiple-input multiple-output (MIMO) communications are widely
recognized as a promising candidate for the next-generation air interface. With
holographic MIMO surface, the number of the spatial degrees-of-freedom (DoFs)
considerably increases and also significantly varies as the user moves. To
fully employ the large and varying number of spatial DoFs, the number of
equipped RF chains has to be larger than or equal to the largest number of
spatial DoFs. However, this causes much waste as radio frequency (RF) chains
(especially the transmit RF chains) are costly and power-hungry. To avoid the
heavy burden, this paper investigates green holographic MIMO communications
with a few transmit RF chains under an electromagnetic-based communication
model. We not only look at the fundamental capacity limits but also propose an
effective transmission, namely non-uniform holographic pattern modulation
(NUHPM), to achieve the capacity limit in the high signal-to-noise (SNR)
regime. The analytical result sheds light on the green evaluation of MIMO
communications, which can be realized by increasing the size of the antenna
aperture without increasing the number of transmit RF chains. Numerical results
are provided to verify our analysis and to show the great performance gain by
employing the additional spatial DoFs as modulation resources.Comment: 10 figures; has been accepted by TGC
Binary-Tree Encoding for Uniform Binary Sources in Index Modulation Systems
The problem of designing bit-to-pattern mappings and power allocation schemes
for orthogonal frequency-division multiplexing (OFDM) systems that employ
subcarrier index modulation (IM) is considered. We assume the binary source
conveys a stream of independent, uniformly distributed bits to the pattern
mapper, which introduces a constraint on the pattern transmission probability
distribution that can be quantified using a binary tree formalism. Under this
constraint, we undertake the task of maximizing the achievable rate subject to
the availability of channel knowledge at the transmitter. The optimization
variables are the pattern probability distribution (i.e., the bit-to-pattern
mapping) and the transmit powers allocated to active subcarriers. To solve the
problem, we first consider the relaxed problem where pattern probabilities are
allowed to take any values in the interval [0,1] subject to a sum probability
constraint. We develop (approximately) optimal solutions to the relaxed problem
by using new bounds and asymptotic results, and then use a novel heuristic
algorithm to project the relaxed solution onto a point in the feasible set of
the constrained problem. Numerical analysis shows that this approach is capable
of achieving the maximum mutual information for the relaxed problem in low and
high-SNR regimes and offers noticeable benefits in terms of achievable rate
relative to a conventional OFDM-IM benchmark.Comment: 18 pages, 16 figures, 2 table
PNRC is a unique nuclear receptor coactivator that stimulates RNA polymerase III-dependent transcription
Transient energy protection based on wavelet packet transform for hybrid bipolar HVDC transmission system
Abstract In hybrid bipolar DC transmission systems with different types of converters at each pole, the transient high‐frequency component of the voltage signal under a single‐pole grounding fault and an inter‐pole fault is significantly different for internal and external faults because of smooth‐wave reactors on both sides of the DC line. Based on these characteristics, a single‐ended electrical quantity protection scheme based on transient energy is proposed. First, the voltage fault component is extracted and then processed by using a wavelet packet transform to obtain the transient energy in each frequency band. Second, the protection criterion is determined based on the ratio between low‐frequency energy and the sum of high‐frequency energy. After the setting principle is given, the influence of the protection scheme under high transition resistance is analysed. The protection scheme is implemented in MATLAB and tested based on fault data obtained from a hybrid bipolar HVDC transmission model built in PSCAD under different operating conditions. The effectiveness of the proposed protection method is verified by simulation tests under different fault types at different fault distances. The proposed method can provide strong tolerance to high transient resistance, accurately identify internal/external faults and automatically identify fault poles
BMPRIA mediated signaling is essential for temporomandibular joint development in mice
The central importance of BMP signaling in the development and homeostasis of synovial joint of appendicular skeleton has been well documented, but its role in the development of temporomandibular joint (TMJ), also classified as a synovial joint, remains completely unknown. In this study, we investigated the function of BMPRIA mediated signaling in TMJ development in mice by transgenic loss-of- and gain-of-function approaches. We found that BMPRIA is expressed in the cranial neural crest (CNC)-derived developing condyle and glenoid fossa, major components of TMJ, as well as the interzone mesenchymal cells. Wnt1-Cre mediated tissue specific inactivation of BmprIa in CNC lineage led to defective TMJ development, including failure of articular disc separation from a hypoplastic condyle, persistence of interzone cells, and failed formation of a functional fibrocartilage layer on the articular surface of the glenoid fossa and condyle, which could be at least partially attributed to the down-regulation of Ihh in the developing condyle and inhibition of apoptosis in the interzone. On the other hand, augmented BMPRIA signaling by Wnt1-Cre driven expression of a constitutively active form of BmprIa (caBmprIa) inhibited osteogenesis of the glenoid fossa and converted the condylar primordium from secondary cartilage to primary cartilage associated with ectopic activation of Smad-dependent pathway but inhibition of JNK pathway, leading to TMJ agenesis. Our results present unambiguous evidence for an essential role of finely tuned BMPRIA mediated signaling in TMJ development
Optical Fiber LSPR Biosensor Prepared by Gold Nanoparticle Assembly on Polyelectrolyte Multilayer
This article provides a novel method of constructing an optical fiber localized surface plasmon resonance (LSPR) biosensor. A gold nanoparticle (NP) assembled film as the sensing layer was built on the polyelectrolyte (PE) multilayer modified sidewall of an unclad optical fiber. By using a trilayer PE structure, we obtained a monodisperse gold NP assembled film. The preparation procedure for this LSPR sensor is simple and time saving. The optical fiber LSPR sensor has higher sensitivity and outstanding reproducibility. The higher anti-interference ability for response to an antibody makes it a promising method in application as a portable immuno-sensor
Altered FGF Signaling Pathways Impair Cell Proliferation and Elevation of Palate Shelves
In palatogenesis, palatal shelves are patterned along the mediolateral axis as well as the anteroposterior axis before the onset of palatal fusion. Fgf10 specifically expressed in lateral mesenchyme of palate maintains Shh transcription in lateral epithelium, while Fgf7 activated in medial mesenchyme by Dlx5, suppressed the expansion of Shh expression to medial epithelium. How FGF signaling pathways regulate the cell behaviors of developing palate remains elusive. In our study, we found that when Fgf8 is ectopically expressed in the embryonic palatal mesenchyme, the elevation of palatal shelves is impaired and the posterior palatal shelves are enlarged, especially in the medial side. The palatal deformity results from the drastic increase of cell proliferation in posterior mesenchyme and decrease of cell proliferation in epithelium. The expression of mesenchymal Fgf10 and epithelial Shh in the lateral palate, as well as the Dlx5 and Fgf7 transcription in the medial mesenchyme are all interrupted, indicating that the epithelial-mesenchymal interactions during palatogenesis are disrupted by the ectopic activation of mesenchymal Fgf8. Besides the altered Fgf7, Fgf10, Dlx5 and Shh expression pattern, the reduced Osr2 expression domain in the lateral mesenchyme also suggests an impaired mediolateral patterning of posterior palate. Moreover, the ectopic Fgf8 expression up-regulates pJak1 throughout the palatal mesenchyme and pErk in the medial mesenchyme, but down-regulates pJak2 in the epithelium, suggesting that during normal palatogenesis, the medial mesenchymal cell proliferation is stimulated by FGF/Erk pathway, while the epithelial cell proliferation is maintained through FGF/Jak2 pathway
Locked Nucleic Acid Pentamers as Universal PCR Primers for Genomic DNA Amplification
Background: Multiplexing technologies, which allow for simultaneous detection of multiple nucleic acid sequences in a single reaction, can save a lot of time, cost and labor compared to traditional single reaction detection methods. However, the multiplexing method currently used requires precise handiwork and many complicated steps, making a new, simpler technique desirable. Oligonucleotides containing locked nucleic acid residues are an attractive tool because they have strong affinities for their complementary targets, they have been used to avoid dimer formation and mismatch hybridization and to enhance efficient priming. In this study, we aimed to investigate the use of locked nucleic acid pentamers for genomic DNA amplification and multiplex genotyping. Results: We designed locked nucleic acid pentamers as universal PCR primers for genomic DNA amplification. The locked nucleic acid pentamers were able to prime amplification of the selected sequences within the investigated genomes, and the resulting products were similar in length to those obtained by restriction digest. In Real Time PCR of genomic DNA from three bacterial species, locked nucleic acid pentamers showed high priming efficiencies. Data from bias tests demonstrated that locked nucleic acid pentamers have equal affinities for each of the six genes tested from the Klebsiella pneumoniae genome. Combined with suspension array genotyping, locked nucleic acid pentamer-based PCR amplification was able to identify a total of 15 strains, including 3 species of bacteria, by gene- and species-specific probes. Among the 32 specie
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