419 research outputs found
Investigating the Role of Retinoblastoma Protein and Transforming Growth Factor-Beta in Growth Inhibition
The Retinoblastoma protein (pRB) is a key regulator of cell proliferation in the G1 phase of the cell cycle. The LxCxE binding cleft is a highly conserved region of pRB. Using a knock-in mouse model, called Rb1∆L, with disrupted pRB and LxCxE interactions, our lab has shown that epithelial cells from Rb1∆L/∆L mice do not respond to TGF-β1 mediated growth arrest. Using shRNAs to deplete the expression of components of LxCxE motif containing complexes, data showed that SAP18 is not involved in TGF-β1 mediated growth arrest. However, depletion of SAP30 and MTA2 compromised TGF-β1 mediated growth arrest. Furthermore, depletion of MTA2 resulted in derepression of E2F target genes in response to TGF-β while depletion of SAP30 repressed the expression of E2F target genes
CDM modeling for corrosion–fatigue life prediction of aluminum alloys
In this study a simple CDM-based corrosion-fatigue model is developed to study the pit to crack transition life in aluminum alloys (Al7075-T651 and Al2024-T351). This study is based on the experimental observation of reduced fatigue life in presence of corrosive environment. Both cases of precorroded fatigue damage and concurrent -corrosion-fatigue damage are discussed. The model is based on the assumption that stress field has no effect on the kinetics of corrosion however, corrosion-induced damage enhances fatigue damage. Model results show -significant reduction in fatigue crack initiation life in both cases of precorrosion and concurrent corrosion–fatigue. The model takes into account the effect of stress, frequency, and temperature on the pit to crack transition life. Model results are compared with the experimental data when available
A computational framework for prediction of atmospheric
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An Entrepreneurial Business Model for Personal Branding: Proposing a Framework
Purpose- Personal branding has become a mature field of research; however, there are many ques-tions to be answered yet. One of the most important questions is that what does a typical entrepre-neurial business model look like?
Design/methodology/approach- To answer the above question, the present paper tries to use meta-analysis approach to making an integrated view of the extant literature. Thus, 25 papers, which were mainly focusing on the topic, was selected and critically reviewed. Finally, a framework is proposed based on Osterwalder's (2004) approach.
Findings- Findings of this research are mainly focused on the characteristics of each dimension in the entrepreneurial business model for personal branding.
Research limitations/implications- Research implications imply that a typical entrepreneurial busi-ness model for personal branding might be helpful for both entrepreneurs as well as policy makers.
Research paper
Reference to this paper should be made as follows: Raftari, M. and Amiri, B. (2014). ―An Entrepre-neurial Business Model for Personal Branding: Proposing a Framework‖, Journal of Entrepreneur-ship, Business and Economics, Vol. 2, No. 2, pp. 121–139
A Road to Ecocritical Insight in Virginia Woolf’s To the Lighthouse
This article is going to study the ecocritical conception in Virginia Woolf’s (1882-1941) novel, To the Lighthouse (TL) (1927). This is an ecocritical reading which uses Lawrence Buell (1939- ) and Derek Wall’s (1965- ) ideas of ecocriticism. Lawrence Buell defined eco-criticism as the study of the relationships between literature and environment in an environmentalist praxis or as a critical insurgency mainly focused on the issue rather than methodology like what cultural studies of identity and body have done. Writers create their works under the influence of environment and nature and a literary work is not created void of nature. Literary works beyond of concepts and contents which are addressed by writers indicate the interaction of human and nature. Wall believes that ecology in particular and the environmental sciences in general have demonstrated how closely one’s species is connected to all other in a web or net of life connections. To the Lighthouse (TL) takes place in a summerhouse near the sea and its main goal is traveling to the Lighthouse amid the sea. There are many natural parts and nature’s elements which are studied in detail to reveal the relation of ecocriticism and literature. This article studies the close relation of man and nature and notes that there is an intimate relation between them. There is a bilateral relation between nature and man; they affect each other in several ways. Woolf’s To the Lighthouse is a good context to portray ecocriticism and green cultural studies. Woolf constructs a remarkable and moving examination of the complex tensions and allegiances of family life from the seemingly trivial postponement of a visit to a nearby lighthouse
Building environmental history for naval aircraft
Operating environments of Navy aircraft vary to a good degree depending upon the squadron location, flight requirements, and other related field and ground activities. All these conditions promote both mechanical and environmental damage of various types. Uniform stress free corrosion arises from the geographical location ambient weather and the average ground time of the aircraft. Even a small scratch during operation can lead to a corrosion cell arising under a surface moisture film. Use of de-icing salts in cold environments will also accelerate the corrosion process. Crevice corrosion, meanwhile, results from the accumulation of dirt and debris in confined spaces such as access door flanges and wheel wells; as well as capillary action that keeps faying surfaces wetted even in low humidity exterior conditions. Due to the presence of wet condensates and appreciable concentrations of chloride (and other active) ions, many areas of the aircraft are prone for pitting, intergranular attack or exfoliation. The aircraft operations will also have influence on type and morphology of corrosion. Thus, building an environmental history of the aircraft is crucial to correctly identify different corrosion and mechanical damage processes to monitor and track the development of attack in many areas of the aircraft structure.
We outline a method for building the environmental history of Naval aircraft using three available resources: maintenance and materials management (3M) system data, daily weather history data of the squadron location, and field activity data as recorded in logbooks. This includes development of a part-specific microclimate builder which tracks a local climate history specific to a part or component. The climate builder takes the flight information such as flight duration, altitude, geographical location, etc., as well as daily weather history data from the NOAA Database. It will translate the asset service history (such as: stored indoors vs. outdoors) into a series of scenarios and assigns weighting factors to these scenarios based on geographical location. The underlying approach that is currently used in the climate scenario builder is based on both models/simulations and sensor data. Our current suite of models combined with the climate builder will provide an integrated framework within which life prediction for a combinatorial situation of mechanical and environmental history can be performed
Effectiveness of acceptance and commitment therapy on emotion regulation in epileptic patients
Background: Epilepsy can severely affect cognitive-emotional and behavioral function. Using an appropriate treatment method to deal with it in order to treat emotional disorders can be an effective action due to the importance of this disorder. This study attempted to investigate the effectiveness of Acceptance and commitment therapy (ACT) on the emotion regulation in patients with epilepsy.
Methods: It was a quasi-experimental study (pretest-posttest design with equal control group) and the sample consisted of 30 patients with epilepsy selected purposefully and assigned into experimental (n=15) and control (n=15) groups randomly. The instrument included the Garnefski et al. Cognitive Emotion Regulation Questionnaire (CERQ). Data were analyzed using SPSS software version 21 conducting MANCOVA and ANCOVA analysis of covariance.
Results: The results showed that the ACT decreased negative emotion regulation and also increased positive emotion regulation in patients with epilepsy in the experimental group compared to the control group. The results of one-way analysis of covariance with the pretest control showed that there was a significant difference between the experimental and control groups in patients with epilepsy in terms of positive emotion regulation (F = 100.55, p <0.001) and negative emotion regulation (F = 154.64, p <0.001).
Conclusion: It can be argued that ACT reduced negative emotion regulation and increased positive emotion regulation in patients with epilepsy
Electrochemical activities at the crack tip: A localized approach
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Advances in proteomics analytical techniques
  Proteins are fundamental components of cells which mediate many essential biological processes. Proteomics is a rapidly growing field for the study of proteome, the protein complement expressed by the genome of an organism or cell type. The large-scale analysis of proteins leads to a more comprehensive view of molecular and cellular pathways that improves the overall understanding of the complex processes supporting the living systems. The analysis of proteome is significantly challenging due to high dynamic range and difficulties in assessment of low abundance proteins and the absence of efficient purification and identification techniques. A variety of methods have been utilized for protein studies including gel-based techniques, protein microarrays, mass spectrometry-based approaches such as MALDI and SELDI, high and ultra-performance liquid chromatography and fourier transform ion cyclotron resonance mass spectrometry. NMR spectroscopy and X-Ray crystallography methods are also used for structural study of proteins. This review aims to give a brief overview of some of the above techniques and their most recent advances. We also introduce Proteominer, a recent protein enrichment technology for the exploration of the entire proteome conten
Analysis of cell cycle position in mammalian cells
The regulation of cell proliferation is central to tissue morphogenesis during the development of multicellular organisms. Furthermore, loss of control of cell proliferation underlies the pathology of diseases like cancer. As such there is great need to be able to investigate cell proliferation and quantitate the proportion of cells in each phase of the cell cycle. It is also of vital importance to indistinguishably identify cells that are replicating their DNA within a larger population. Since a cell′s decision to proliferate is made in the G1 phase immediately before initiating DNA synthesis and progressing through the rest of the cell cycle, detection of DNA synthesis at this stage allows for an unambiguous determination of the status of growth regulation in cell culture experiments. DNA content in cells can be readily quantitated by flow cytometry of cells stained with propidium iodide, a fluorescent DNA intercalating dye. Similarly, active DNA synthesis can be quantitated by culturing cells in the presence of radioactive thymidine, harvesting the cells, and measuring the incorporation of radioactivity into an acid insoluble fraction. We have considerable expertise with cell cycle analysis and recommend a different approach. We Investigate cell proliferation using bromodeoxyuridine/fluorodeoxyuridine (abbreviated simply as BrdU) staining that detects the incorporation of these thymine analogs into recently synthesized DNA. Labeling and staining cells with BrdU, combined with total DNA staining by propidium iodide and analysis by flow cytometry1 offers the most accurate measure of cells in the various stages of the cell cycle. It is our preferred method because it combines the detection of active DNA synthesis, through antibody based staining of BrdU, with total DNA content from propidium iodide. This allows for the clear separation of cells in G1 from early S phase, or late S phase from G2/M. Furthermore, this approach can be utilized to investigate the effects of many different cell stimuli and pharmacologic agents on the regulation of progression through these different cell cycle phases. In this report we describe methods for labeling and staining cultured cells, as well as their analysis by flow cytometry. We also include experimental examples of how this method can be used to measure the effects of growth inhibiting signals from cytokines such as TGF-β1, and proliferative inhibitors such as the cyclin dependent kinase inhibitor, p27KIP1. We also include an alternate protocol that allows for the analysis of cell cycle position in a sub-population of cells within a larger culture5. In this case, we demonstrate how to detect a cell cycle arrest in cells transfected with the retinoblastoma gene even when greatly outnumbered by untransfected cells in the same culture. These examples illustrate the many ways that DNA staining and flow cytometry can be utilized and adapted to investigate fundamental questions of mammalian cell cycle control. © 2012 Creative Commons Attribution License
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