4,278 research outputs found
Integrating static and dynamic information for routing traffic
The efficiency of traffic routing on complex networks can be reflected by two
key measurements i.e. the system capacity and the average data packets travel
time. In this paper, we propose a mixing routing strategy by integrating local
static and dynamic information for enhancing the efficiency of traffic on
scale-free networks. The strategy is governed by a single parameter. Simulation
results show that there exists a optimal parameter value by considering both
maximizing the network capacity and reducing the packet travel time. Comparing
with the strategy by adopting exclusive local static information, the new
strategy shows its advantages in improving the efficiency of the system. The
detailed analysis of the mixing strategy is provided. This work suggests that
how to effectively utilize the larger degree nodes plays the key role in the
scale-free traffic systems.Comment: 5 pages, 5 figure
A Study on Expression and Tyrosine 705 phosphorylation of STAT3 in Focal Cerebral Ischemia-Reperfusion Rat Model and its Role in Neuronal Apoptosis
Purpose: To investigate the expression and tyrosine 705 phosphorylation of STAT3 in focal cerebral ischemia-reperfusion rat model and its role in neuronal apoptosis.Methods: Ischemia-reperfusion model was established by thread-occluded method. Tetrazolium red (TTC), H/E and Nissl staining were used to evaluate whether ischemia-reperfusion model was successfully established. TUNEL staining and immunohistochemistry were employed to monitor apoptosis-positive nerve cells as well as STAT3-, p-Tyr705-STAT3-, Bcl-2- and Fas-positive cells in ischemic penumbra (IP) and ischemic core (IC).Results: The results of TTC, HE and Nissl staining indicated that the ischemia reperfusion model was successfully established. After 3 h, ischemia followed by different reperfusion times, the STAT3-, p- Tyr705-STAT3-, Fas- and Bcl-2 positive cells counts and the apoptosis-positive nerve cells count were significantly (p < 0.05 or 0.01) increased to 27.20, 29.20, 15.90, 18.50, and 202.00 in IP and 19.50, 21.20, 12.50, 12.40, and 97.80 in IC, compared with the sham-operated group. As reperfusion times increased, cell counts did not decrease significantly relative to control group. Correlation analysis indicate that there was significant (p < 0.01) positive correlations among STAT3-, p-Tyr705 STAT3-, Fas- and Bcl-2-positive cells counts on the one hand, and apoptosis positive nerve cells count in IP and IC, on the other hand.Conclusion: Regulating expression and tyrosine 705 phosphorylation of STAT3 may be a new and effective strategy for treating cerebral infarction.Keywords: Ischemia-reperfusion, Neuronal apoptosis, STAT3, Phosphorylation, Cerebral infarctio
The Value of Incorporating Review Tags into an Online Review System for User Review Generation
Online review mining has become an important way for businesses to understand consumer preferences and product characteristics. Many online review platforms have started to incorporate the extracted information as review tags to guide future reviews. In this study, we leverage a quasi-experiment from an online health service platform to investigate the value of incorporating the review tags (extracted from prior reviews) into the online review system in user review generation. Our preliminary results show that after the provision of review tags, more reviews are provided for doctors but the length of those reviews is shorter. Notably, we also find a decrease in sentiment and an increase in novel reviews. Our findings provide actionable managerial insights for platform managers to design online review systems
Expression of fatty acid and lipid biosynthetic genes in developing endosperm of Jatropha curcas
BACKGROUND: Temporal and spatial expression of fatty acid and lipid biosynthetic genes are associated with the accumulation of storage lipids in the seeds of oil plants. In jatropha (Jatropha curcas L.), a potential biofuel plant, the storage lipids are mainly synthesized and accumulated in the endosperm of seeds. Although the fatty acid and lipid biosynthetic genes in jatropha have been identified, the expression of these genes at different developing stages of endosperm has not been systemically investigated. RESULTS: Transmission electron microscopy study revealed that the oil body formation in developing endosperm of jatropha seeds initially appeared at 28 days after fertilization (DAF), was actively developed at 42 DAF and reached to the maximum number and size at 56 DAF. Sixty-eight genes that encode enzymes, proteins or their subunits involved in fatty acid and lipid biosynthesis were identified from a normalized cDNA library of jatropha developing endosperm. Gene expression with quantitative reverse-transcription polymerase chain reaction analysis demonstrated that the 68 genes could be collectively grouped into five categories based on the patterns of relative expression of the genes during endosperm development. Category I has 47 genes and they displayed a bell-shaped expression pattern with the peak expression at 28 or 42 DAF, but low expression at 14 and 56 DAF. Category II contains 8 genes and expression of the 8 genes was constantly increased from 14 to 56 DAF. Category III comprises of 2 genes and both genes were constitutively expressed throughout endosperm development. Category IV has 9 genes and they showed a high expression at 14 and 28 DAF, but a decreased expression from 42 to 56 DAF. Category V consists of 2 genes and both genes showed a medium expression at 14 DAF, the lowest expression at 28 or 42 DAF, and the highest expression at 56 DAF. In addition, genes encoding enzymes or proteins with similar function were differentially expressed during endosperm development. CONCLUSION: The formation of oil bodies in jatropha endosperm is developmentally regulated. The expression of the majority of fatty acid and lipid biosynthetic genes is highly consistent with the development of oil bodies and endosperm in jatropha seeds, while the genes encoding enzymes with similar function may be differentially expressed during endosperm development. These results not only provide the initial information on spatial and temporal expression of fatty acid and lipid biosynthetic genes in jatropha developing endosperm, but are also valuable to identify the rate-limiting genes for storage lipid biosynthesis and accumulation during seed development
Unidirectional Photonic Reflector Using a Defective Atomic Lattice
Based on the broken spatial symmetry, we propose a novel scheme for
engineering a unidirectional photonic reflector using a one-dimensional atomic
lattice with defective cells that have been specifically designed to be vacant.
By trapping three-level atoms and driving them into the regime of
electromagnetically induced transparency, and through the skillful design of
the number and position of vacant cells in the lattice, numerical simulations
demonstrate that a broad and high unidirectional reflection region can be
realized within EIT window. This proposed unidirectional reflector scheme
provides a new platform for achieving optical nonreciprocity and has potential
applications for designing optical circuits and devices of nonreciprocity at
extremely low energy levels
Neonatal diethylstilbestrol exposure alters the metabolic profile of uterine epithelial cells
Developmental exposure to diethylstilbestrol (DES) causes reproductive tract malformations, affects fertility and increases the risk of clear cell carcinoma of the vagina and cervix in humans. Previous studies on a well-established mouse DES model demonstrated that it recapitulates many features of the human syndrome, yet the underlying molecular mechanism is far from clear. Using the neonatal DES mouse model, the present study uses global transcript profiling to systematically explore early gene expression changes in individual epithelial and mesenchymal compartments of the neonatal uterus. Over 900 genes show differential expression upon DES treatment in either one or both tissue layers. Interestingly, multiple components of peroxisome proliferator-activated receptor-Îł (PPARÎł)-mediated adipogenesis and lipid metabolism, including PPARÎł itself, are targets of DES in the neonatal uterus. Transmission electron microscopy and Oil-Red O staining further demonstrate a dramatic increase in lipid deposition in uterine epithelial cells upon DES exposure. Neonatal DES exposure also perturbs glucose homeostasis in the uterine epithelium. Some of these neonatal DES-induced metabolic changes appear to last into adulthood, suggesting a permanent effect of DES on energy metabolism in uterine epithelial cells. This study extends the list of biological processes that can be regulated by estrogen or DES, and provides a novel perspective for endocrine disruptor-induced reproductive abnormalities
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