On Chern-Simons theory with an inhomogeneous gauge group and BF theory knot invariants

We study the Chern-Simons topological quantum field theory with an inhomogeneous gauge group, a non-semi-simple group obtained from a semi-simple one by taking its semi-direct product with its Lie algebra. We find that the standard knot observables (i.e. traces of holonomies along knots) essentially vanish, but yet, the non-semi-simplicity of our gauge group allows us to consider a class of un-orthodox observables which breaks gauge invariance at one point and which lead to a non-trivial theory on long knots in $\mathbb{R}^3$. We have two main morals : 1. In the non-semi-simple case, there is more to observe in Chern-Simons theory! There might be other interesting non semi-simple gauge groups to study in this context beyond our example. 2. In our case of an inhomogeneous gauge group, we find that Chern-Simons theory with the un-orthodox observable is actually the same as 3D BF theory with the Cattaneo-Cotta-Ramusino-Martellini knot observable. This leads to a simplification of their results and enables us to generalize and solve a problem they posed regarding the relation between BF theory and the Alexander-Conway polynomial. Our result is that the most general knot invariant coming from pure BF topological quantum field theory is in the algebra generated by the coefficients of the Alexander-Conway polynomial.Comment: To appear in Journal of Mathematical Physics vol.46 issue 12. Available on http://link.aip.org/link/jmapaq/v46/i1

Polynomials in Error Detection and Correction in Data Communication System

The chapter gives an overview of the various types of errors encountered in a communication system. It discusses the various error detection and error correction codes. The role of polynomials in error detection and error correction is discussed in detail with the architecture for practical implementation of the codes in a communication channel

Cavity optomechanics with stoichiometric SiN films

We study high-stress SiN films for reaching the quantum regime with mesoscopic oscillators connected to a room-temperature thermal bath, for which there are stringent requirements on the oscillators' quality factors and frequencies. Our SiN films support mechanical modes with unprecedented products of mechanical quality factor $Q_m$ and frequency $\nu_m$ reaching $Q_{m} \nu_m \simeq2 \times 10^{13}$ Hz. The SiN membranes exhibit a low optical absorption characterized by Im$(n) \lesssim 10^{-5}$ at 935 nm, representing a 15 times reduction for SiN membranes. We have developed an apparatus to simultaneously cool the motion of multiple mechanical modes based on a short, high-finesse Fabry-Perot cavity and present initial cooling results along with future possibilities.Comment: 4 pages, 5 figure

Differential induction of inflammatory cytokines by dendritic cells treated with novel TLR-agonist and cytokine based cocktails: targeting dendritic cells in autoimmunity

<p>Abstract</p> <p>Background</p> <p>Dendritic cells (DC) are main gate-keepers of the immune system, bridging the innate and adaptive immune system. DCs are able to mature into inflammatory DCs at sites of inflammation in both autoimmune and allergic disease, thereby sustaining a continuous activation of the adaptive immune system at sites of inflammation. This function of DCs makes them attractive target cells for therapeutic intervention in inflammatory diseases. We have designed a DC-based screening model by which drug candidates can be evaluated for their ability to suppress DC maturation into an inflammatory and disease promoting phenotype.</p> <p>Methods</p> <p>Human monocyte derived DCs were differentiated using IL-4 and GM-CSF to immature DCs (imDCs). The imDCs were treated with various combinations of TLR-agonists and pro-inflammatory cytokines to identify cocktails with ability to mature imDCs into inflammatory DCs. The effect of the cocktails on DC maturation was evaluated using ELISA and cytokine arrays to measure secreted cytokines and chemokines. FACS analysis was used to assess expression of maturation markers, and functional studies were carried out using naïve allogeneic T-cells to assay for a Th1-promoting DC phenotype.</p> <p>Results</p> <p>Nine cocktails were designed with potent ability to induce secretion of the Th1-promoting cytokines IL-12p70 and TNFα from imDCs, and three were able to induce the Th17-promoting cytokine IL-23. The cocktails were further characterized using cytokine arrays, showing induction of inflammation related cytokines and chemokines like CXCL10, CCL2, CCL4, CCL8, CCL15, CCL20 and IL-8, of which some are present in a range of autoimmune pathologies. Prostaglandin E2 secretion was identified from DCs treated with TLR agonists poly I:C and peptidoglycan, but not LPS. The cocktails were able to induce DC maturation markers like HLA-DR, CD40, CD80, CD83 and CD86, except the TLR7/8 agonist R848. Functional end-points made by co-culture of allogeneic CD4⁺T cells with the cocktail treated DCs, showed that five cocktails in particular could induce a classical Th1-phenotype with ability to secrete high amounts of the hall-mark cytokine IFNγ. The model was validated using dexamethasone and two COX-inhibitors, which were able to suppress the cocktail driven pro-inflammatory DC maturation.</p> <p>Conclusions</p> <p>The identification of novel Th1-promoting cocktails allows screening of anti-inflammatory drug candidates by assessing the ability to suppress the activation and differentiation of imDCs into inflammatory DCs with a specific Th1-promoting phenotype. The model thus provides a screening tool, which can identify potential anti-inflammatory effects on the natural regulator of the immune response, the dendritic cell.</p

Self-consistent treatment of the self-energy in nuclear matter

The influence of hole-hole propagation in addition to the conventional particle-particle propagation, on the energy per nucleon and the momentum distribution is investigated. The results are compared to the Brueckner-Hartree-Fock (BHF) calculations with a continuous choice and conventional choice for the single-particle spectrum. The Bethe-Goldstone equation has been solved using realistic $NN$ interactions. Also, the structure of nucleon self-energy in nuclear matter is evaluated. All the self-energies are calculated self-consistently. Starting from the BHF approximation without the usual angle-average approximation, the effects of hole-hole contributions and a self-consistent treatment within the framework of the Green function approach are investigated. Using the self-consistent self-energy, the hole and particle self-consistent spectral functions including the particle-particle and hole-hole ladder contributions in nuclear matter are calculated using realistic $NN$ interactions. We found that, the difference in binding energy between both results, i.e. BHF and self-consistent Green function, is not large. This explains why is the BHF ignored the 2h1p contribution.Comment: Preprint 20 pages including 15 figures and one tabl

FIBRINOLYTIC ENZYME FROM BACILLUS AMYLOLIQUEFACIENS: OPTIMISATION AND SCALE UP STUDIES

Objective: This research work was carried out to identify a potent microorganism, which produced the fibrinolytic enzyme and to optimise the media and growth parameters to achieve the maximal enzyme production for commercial application. Methods: Microorganisms were isolated from different sources and assayed for fibrinolytic activity. The shortlisted cultures after preliminary screening (casein hydrolysis, blood plate assay and blood clot dissolution) were identified using 16S rRNA amplification method. The media and growth parameters were optimized to achieve the maximal enzyme activity. In-silico studies were carried out to identify the activators and inhibitors of the enzyme. Results: Two species of Bacillus, namely, Bacillus amyloliquefaciens and Bacillus licheniformis, isolated from spoilt milk and soy flour, respectively, exhibited fibrinolytic activity. In the laboratory scale studies, of these two cultures, B. amyloliquefaciens produced the Fibrinolytic enzyme in higher quantities, 28.98 FU/mL, compared to 26.63 FU/mL in B. licheniformis. The maximal activities were obtained after 72 h. The optimum conditions at laboratory scale for the maximal production of the fibrinolytic enzyme were: pH 7.2, temperature 37 C and agitation 200 rpm. When scale up studies with B. amyloliquefaciens in a 7 L Fermentor were undertaken. The maximal activity obtained was 55.60 FU/mL in 72 h, compared to that of 28.98 FU/mL in shake flask studies. The molecular weight of the enzyme was estimated to be about 38 kDa. In in-silico studies, it was observed that PMSF inhibited the fibrinolytic activity, thereby, confirming this fibrinolytic enzyme is a serine protease (Nattokinase). Conclusion: The enzyme had exhibited excellent blood clot dissolving property and therefore may be considered for further scale up and commercial exploitation

Energy and Momentum densities of cosmological models, with equation of state ρ=μ\rho=\mu, in general relativity and teleparallel gravity

We calculated the energy and momentum densities of stiff fluid solutions, using Einstein, Bergmann-Thomson and Landau-Lifshitz energy-momentum complexes, in both general relativity and teleparallel gravity. In our analysis we get different results comparing the aforementioned complexes with each other when calculated in the same gravitational theory, either this is in general relativity and teleparallel gravity. However, interestingly enough, each complex's value is the same either in general relativity or teleparallel gravity. Our results sustain that (i) general relativity or teleparallel gravity are equivalent theories (ii) different energy-momentum complexes do not provide the same energy and momentum densities neither in general relativity nor in teleparallel gravity. In the context of the theory of teleparallel gravity, the vector and axial-vector parts of the torsion are obtained. We show that the axial-vector torsion vanishes for the space-time under study.Comment: 15 pages, no figures, Minor typos corrected; version to appear in International Journal of Theoretical Physic