687,097 research outputs found

    Effect of dispersion state of Cloisite15A® on the performance of SPEEK/Cloisite15A nanocomposite membrane for DMFC application

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    The introduction of 2,4,6-triaminopyrimidine (TAP) into sulfonated poly(ether ether ketone) (SPEEK)/Cloisite15A® nanocomposite membranes were investigated for the purpose of maintaining low methanol permeability and suppressing swelling in direct methanol fuel cell (DMFC). SPEEK with 63% of degree of sulfonation (DS) was prepared by sulfonation of PEEK. Cloisite15A (7.5 wt %) along with various weight loading of TAP was incorporated into SPEEK matrix via solution intercalation method. The effect of TAP loading on the SPEEK/Cloisite15A/TAP morphology was studied. The beneficial impact of the SPEEK/Cloisite15A/TAP morphology on the physicochemical properties of the membrane was further discussed. Swelling behavior, ion exchange capacity (IEC), proton conductivity, and methanol permeability of the resultant membranes were determined as a function of Cloisite15A and TAP loadings. Uniform distribution of Cloisite15A particles in the SPEEK polymer matrix in the homogenous SPEEK/Cloisite15A/TAP nanocomposite membranes was confirmed by scanning electron microscopy and X-ray diffraction. The water uptake of the SPEEK nanocomposite membranes decreased dramatically in the presence of TAP. The significant selectivity of SP/7.5/7.5 nanocomposite membranes could indicate a potential feasibility as a promising electrolyte for DMFC

    Quantum TAP equations

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    We derive Thouless-Anderson-Palmer (TAP) equations for quantum disordered systems. We apply them to the study of the paramagnetic and glassy phases in the quantum version of the spherical p spin-glass model. We generalize several useful quantities (complexity, threshold level, etc.) and various ideas (configurational entropy crisis, etc), that have been developed within the classical TAP approach, to quantum systems. The analysis of the quantum TAP equations allows us to show that the phase diagram (temperature-quantum parameter) of the p spin-glass model should be generic. In particular, we argue that a crossover from a second order thermodynamic transition close to the classical critical point to a first order thermodynamic transition close to the quantum critical point is to be expected in a large class of systems.Comment: 29 pages, 4 fi

    Varicellovirus UL 49.5 proteins differentially affect the function of the transporter associated with antigen processing, TAP

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    Cytotoxic T-lymphocytes play an important role in the protection against viral infections, which they detect through the recognition of virus-derived peptides, presented in the context of MHC class I molecules at the surface of the infected cell. The transporter associated with antigen processing (TAP) plays an essential role in MHC class I–restricted antigen presentation, as TAP imports peptides into the ER, where peptide loading of MHC class I molecules takes place. In this study, the UL49.5 proteins of the varicelloviruses bovine herpesvirus 1 (BHV-1), pseudorabies virus (PRV), and equine herpesvirus 1 and 4 (EHV-1 and EHV-4) are characterized as members of a novel class of viral immune evasion proteins. These UL49.5 proteins interfere with MHC class I antigen presentation by blocking the supply of antigenic peptides through inhibition of TAP. BHV-1, PRV, and EHV-1 recombinant viruses lacking UL49.5 no longer interfere with peptide transport. Combined with the observation that the individually expressed UL49.5 proteins block TAP as well, these data indicate that UL49.5 is the viral factor that is both necessary and sufficient to abolish TAP function during productive infection by these viruses. The mechanisms through which the UL49.5 proteins of BHV-1, PRV, EHV-1, and EHV-4 block TAP exhibit surprising diversity. BHV-1 UL49.5 targets TAP for proteasomal degradation, whereas EHV-1 and EHV-4 UL49.5 interfere with the binding of ATP to TAP. In contrast, TAP stability and ATP recruitment are not affected by PRV UL49.5, although it has the capacity to arrest the peptide transporter in a translocation-incompetent state, a property shared with the BHV-1 and EHV-1 UL49.5. Taken together, these results classify the UL49.5 gene products of BHV-1, PRV, EHV-1, and EHV-4 as members of a novel family of viral immune evasion proteins, inhibiting TAP through a variety of mechanisms

    Data transfer between Cad system and RP system: a report

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    Rapid Prototyping (RP) is a technology that transform a design generated in Computer Aided Design (CAD) to a 3D model parts. CAD models are usually done on a CAD system and then transported into the RP system. A good interface between the CAD and the RP system is one of the key factors of producing a good quality prototype. This paper reports on the results of an experimentation carried out to identify the problems in transferring data between a CAD system (UNIGRAPHICS) and an RP system (QUICKSLICE). Based on the experimentation’s results and analysis, a basic guideline is proposed for a safer data transfer between the CAD system (UNIGRAPHICS) and an RP system (QUICKSLICE)

    American Tap Dance History and Proposed Preservation

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    The first form of dance conceived in the United States, tap dance, thrived throughout the era of vaudeville and the movie musical. Today’s society often overlooks tap dance beyond basic or beginner dance education; the history of the art from is even more so neglected. Within these pages, I will address the question of how the history of tap dance can be honored and preserved for generations to come. I feel so grateful to have had a tap mentor that valued the history of tap just as much as the technique and steps. Others in my field may not have been so lucky. This is ultimately a major hinderance in our ability as dance educators to future students. Developing a system of tap dance training accompanied by history as well as sparking the interest of audiences new and old is the best way to further tap technique and performance. Thanks to popular television programs such as World of Dance and So You Think You Can Dance, dance, in general, has seen a major resurgence in modern culture. Registration in dance schools, participation in dance conventions, and attendance in dance related performances is steadily on the rise with no sign of slowing down. In light of this, there has not been a better time to examine the way in which dance history is taught and conveyed; we must take advantage of the peaked interest and utilize all resources at hand. Tap dance, in particular, has seen its own small portion of this widespread dance resurgence especially due to the return of the movie musical - La La Land and The Greatest Showman. With the demand of dance on an upswing, inadequate, lackluster dance education is a serious concern. Dance teachers need to make sure the knowledge they are imparting on students is both historically accurate and progressive. In order to best educate myself and develop a viable solution, I have done extensive historical research through credible texts. I have read various books suggested to me by my own tap mentor and other tap professionals. I have also be read through various biographies and autobiographies. Now having obtained as much knowledge as possible regarding the history of tap dance, I efficiently developed a method in which preservation can take place within the teaching of technique. Tap dance, being one of the only forms of dance originating in the United States, deserves to be sustained and honored properly and to the highest degree
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