Vector In Presence Research Articles

Dealing with T and CPT violations in mixing as well as direct and indirect CP violations for neutral mesons decaying to two vectors

A large number of observables can be constructed from differential decay rate based on the polarization of final state while considering decay of a neutral meson (P^{0} text { or } {bar{P}}^{0}) to two vector particles. But all of these observables are not independent to each other since there are only a few independent theoretical parameters controlling the whole dynamics and therefore various relations among observables emerge. In this paper, we have studied the behaviour of observables for neutral meson decaying to two vectors in presence of T and C!P T violations in mixing accompanied by both direct and indirect C!P violations. We have expressed all of the fourteen unknown theoretical parameters for this scenario in terms observables only and constructed the complete set of thirty four relations among observables whose violation would signify the existence of some new Physics involving direct violation of C!P T. In addition, using this formalism we have studied three special cases too: (a) SM scenario, (b) SM plus direct C!P violation (c) SM plus T and C!P T violation in mixing.

Adaptive cooperative sensing in cognitive radio networks with ensemble model for primary user detection

SummaryOpportunistic spectrum sharing ability enables higher spectrum utilization in cognitive radio networks. Detecting the presence of primary user in the network is the most important functionality in cognitive radio network as the cognitive users cannot use the spectrum with interference to primary users. Most solutions proposed for primary user detection suffer from hidden terminal problem resulting from multipath fading and shadow effects. The work focus on Rayleigh and Nakagami fading channel with comparable nonfading AWGN channel in cognitive radio. An ensemble model to detect the presence of primary user with high confidence is proposed in this work. The approach is based on training machine learning models with energy vectors in presence and absence of primary users. The trained model is then used to predict the primary user based on the energy vector.

Improved Recovery of Analysis Sparse Vectors in Presence of Prior Information

In this letter, we consider the problem of recovering analysis-sparse signals from under-sampled measurements when some prior information about the support is available. We incorporate such information in the recovery stage by suitably tuning the weights in a weighted L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> -analysis optimization problem. Indeed, we try to set the weights such that the method succeeds with minimum number of measurements. For this purpose, we exploit the upper-bound on the statistical dimension of a certain cone to determine the weights. Our numerical simulations confirm that the introduced method with tuned weights outperforms the standard L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> -analysis technique.

Pullulan-PEI-Histidine towards gene delivery: vector unpacking with respect to molecular weight and cytoplasmic histones

Event Abstract Back to Event Pullulan-PEI-Histidine towards gene delivery: vector unpacking with respect to molecular weight and cytoplasmic histones Rekha M. Ramesan1 1 Sree Chitra Tirunal Institute for Medical Sciences & Technology, Biosurface Technology, BiomedicalTechnology Wing, India Introduction: Cationic polymers, one of the most important nonviral vectors have a number of advantages over viral vectors. However cationic surface charge, the key factor which determines the transfection efficiency, is also one of the limitations associated with it. Major limiting factors are cytotoxicity, biocompatibility and the release of the cargo from the vector intracellularly. The tightly formed nanoplexes gains entry into the cells, however it doesn’t lead to good transfection if the DNA remains tightly bound to carrier. Schaffer et.al proved that unpacking of the DNA from the vectors is a major limiting step in the process of non-viral gene delivery[1]. Earlier we reported the possible role of histones in unpacking in which a combination of all histones were used[2]. In this work we attempted to evaluate the possible role played by the molecular weight of the polymers and which of the cytoplasmic histones aids more in vector unpacking. Histone 1 (H1) and histone 3 (H3) reported to be found in cytoplasm were used for the study. Materials and Methods: Pullulan a hydrophilic, nonionic polysaccharide was conjugated with PEI (10 and 25KDa) to which histidine was introduced to improve its transfection efficiency (PPE10H and PPE25H). The conjugation was extablished by variuos techniques including NMR. The particle size and zetapotential of nanoplexes was evaluated with DLS. The cellular uptake and transfection efficiency was done in C6 glioma cells. For vector unpacking studies, cellulose-DNA beads were used by which the displacement of the polymer was assessed. Labelled PPEH and histones (H 1 and H 3) were used to study the unpacking in cell lines. Results and Discussion: The derivatisation was established using techniques including NMR and Raman spectroscopy. The optimum size of PPE10H and PPE25H nanoplexes were 78.4 ± 0.72 and 101.6 ± 2.3 respectively at 1:4 ratio with a zeta potential in the range 13-15 mV. The nanoplexes of both polymers demonstrated very high intracellular uptake and PPE10H had higher transfection efficiency in comparison with PEI10K and PPE10KH. Among the histones studied H3 was found to be more efficient in vector unpacking (Fig.1). In the absence of histone intact nanoplex is internalised as TRITC labeled PPE10H is found in the cytoplasm and tagged DNA in the nucleus. The nanoplex treated with H1 and H3 resulted in unpacking outside the cell and the labeled polymers are excluded from the entry into the cells (Fig. 1 B to E). However H1 is not as efficient as H3 in unpacking the DNA from the polyplex. The vector unpacking was higher with PPEH10K which might be the reason for better transfection efficacy which could be attributed to its low cationicity (Fig. 2). Figure 1. Internalization of TRITC labeled PPE10KH nanoplex in C6 cells. Nanoplex alone (A), nanoplex treated with 500 ng histone H1 (B), 1 micro g histone H1 (C), 500 ng histone H3 (D) and 1 micro g histone H3 (E) . Absence of TRITC labeled polymer in D & E indicate the better displacement of polymer with H3. Figure 2. Luciferase expression in C6 cells transfected by PPE10H and PEI complexes at ratios 1:3 and 1:4. ** p<0.05 Conclusion: PPE10H was found to be a better transfecting agent. It was observed that H3 is more effiecient in displacing the plasmid DNA from the vector. The extent of cationicity also found to play a role in release of DNA from the vector in presence of histones.

Transgene Expression of Green Fluorescent Protein and Germ Line Transmission in Cloned Pigs Derived fromIn VitroTransfected Adult Fibroblasts

The pig represents the xenogeneic donor of choice for future organ transplantation in humans for anatomical and physiological reasons. However, to bypass several immunological barriers, strong and stable human genes expression must occur in the pig's organs. In this study we created transgenic pigs using in vitro transfection of cultured cells combined with somatic cell nuclear transfer (SCNT) to evaluate the ubiquitous transgene expression driven by pCAGGS vector in presence of different selectors. pCAGGS confirmed to be a very effective vector for ubiquitous transgene expression, irrespective of the selector that was used. Green fluorescent protein (GFP) expression observed in transfected fibroblasts was also maintained after nuclear transfer, through pre- and postimplantation development, at birth and during adulthood. Germ line transmission without silencing of the transgene was demonstrated. The ubiquitous expression of GFP was clearly confirmed in several tissues including endothelial cells, thus making it a suitable vector for the expression of multiple genes relevant to xenotransplantation where tissue specificity is not required. Finally cotransfection of green and red fluorescence protein transgenes was performed in fibroblasts and after nuclear transfer blastocysts expressing both fluorescent proteins were obtained.

Estimation of mean vector in presence of non-response

Simultaneous estimation of means of several variables is considered for finite population in presence of non-response. Two types of nonresponses (partial and complete) are considered using the technique of sampling and subsampling with equal probabilities without replacement. The optimum sample size and the optimum value of subsampling fraction to be repeated from the nonresponding units of the sample have been obtained for fixed survey budget.

Gene Therapy of Metastatic Pancreas Cancer with Intraperitoneal Injections of Concentrated Retroviral Herpes Simplex Thymidine Kinase Vector Supernatant and Ganciclovir

The objective of this study was to determine the efficacy of intraperitoneal (IP) injections of a new concentrated herpes simplex thymidine kinase (HS-tk) retroviral vector and ganciclovir (GCV) for peritoneal metastases from pancreas cancer. Metastatic pancreas cancer is fatal. Gene therapy may provide a novel approach for this disease. Gene therapy with adeno- or retroviral-mediated transfer of the HS-tk gene into tumor cells renders the cells susceptible to GCV. Intratumoral or intracavity injections of retroviral vectors have been ineffective in previous studies. Pancreatic cancer B x PC3 cells (3 x 10(7)) were injected into the tail of pancreas in nude mice. Mice received IP injections of a concentrated HS-tk vector (5 x 10(7)) cfu/mliters) or a control vector (G1Na) without the tk gene for 10 days and GCV (100 mg/kg) for 14 days. To determine whether the vector would survive in the milieu of the peritoneal cavity, the authors examined the effects of ascitic fluid on the vector. Pancreas cancer cells were transduced in vitro with HS-tk vector in presence of media or ascitic fluid and treated with GCV. Highly significant reductions in the mass of metastatic peritoneal tumor deposits were found in HS-tk-treated group (124 +/- 27 mg; n = 11) compared with G1Na vector controls (910 +/- 168 mg; n = 8; p < 0.0001). Results of polymerase chain reaction analysis demonstrated integration of the vector in the tumors, and on immunohistochemistry, expression of the TK protein was seen in the number of surviving colonies (representing nontransduced cells) were similar in both groups, suggesting that the vector effectively transduced tumor cells bathed in the ascitic fluid. Results demonstrate that IP administration of concentrated retroviral HS-tk vectors is effective treatment for pancreas cancer metastatic to the peritoneal cavity; furthermore, the vector is active in the presence of ascitic fluid. Intraperitoneal retroviral HS-tk may provide a novel approach to treatment of metastatic pancreas cancer.

Technology and technical change in a dynamic production model

The basic features of input-output production models are briefly reviewed. It is argued that some of the assumptions and the consequent mathematical setting underlying input-output models should be revised when (a) substitution effects prevail over growth-decline effects, (b) technological innovation is taken into account. In this light, the standard dynamic version of a Leontief model is criticized in order to arrive at a more general formulation of a production-innovation model. Some properties of this model are then illustrated and the economic meaning of the results is discussed. The main conclusion is that it is possible to establish a certain long-term invariance of the production vector in presence of uncertainties affecting technology, investment and consumption patterns.

Nonuniqueness of resolution of hertz vector in presence of a boundary, and the horizontal dipole problem

It is proved that Sommerfeld's resolution of \Pi, \Pi=(\Pi_{x},0,\Pi_{z}) for the x directed dipole source in the classical dipole problem is not unique and is just one of four acceptable resolutions. A method is shown for analytically obtaining one such acceptable resolution, namely, \Pi=(\Pi_{x},\Pi_{y},0) . With this resolution, the geometrical optics results for the dipole problem are obtained.