Ablation of Post Transplant Atrial Flutter and Pseudo-fibrillation Using Magnetic Navigation via a Superior Approach.

Ablation of cavotricuspid ishtmus flutter and atrial tachycardia in a complex substrate has never been reported using remote navigation via superior approach. Venous access was obtained via right internal jugular for ablation and left subclavian for duodecapolar catheter placement into the coronary sinus. In a posttransplant patient presenting with both regular and irregular tachycardia, both cavotricuspid isthmus flutter in the donor and atrial tachycardia in the recipient was mapped using a two catheter approach. Successful ablation of typical atrial flutter and anastomotic block was achieved. This is the first report of successful ablation of cavotricuspid isthmus flutter and posttransplant atrial tachycardia using magnetic navigation via superior approach. Using only two catheters, this approach is logical and feasible in complex substrates with interrupted inferior venous access

Study of Biaxial Fatigue Behavior of Fiber Reinforced Polymers Under Tensile and Shear Loadings

Fiber reinforced polymers are used in many structural applications in the aerospace and automotive industries because of their high strength to weight and high modulus to weight ratios. In many of these applications, they are used as thin laminated panels comprising of multiple layers of continuous fibers embedded in a polymer matrix. In general, these laminates behave as an orthotropic material and their properties are direction-dependent. While their uniaxial static and fatigue characteristics have been studied extensively, their biaxial static and fatigue characteristics are not well established. One reason for this is the difficulty of conducting biaxial tests, especially under cyclic loading conditions. The objectives of the current research are two folds: (1) develop a biaxial test method that can be applied to a range of normal and shear loadings, and (2) study the biaxial fatigue behavior of a fiber reinforced polymer laminate using the new test method. The test method developed in this research is based on a butterfly-shaped Arcan specimen. The versatility of the Arcan specimen is that it can be utilized for testing materials under uniaxial normal loading, shear loading or a combination of in-plane normal and shear loadings. The laminate considered in this study was a [0/90/04/0]S Eglass/epoxy. Finite element analysis of a butterfly-shaped Arcan specimen was conducted first to establish its optimum geometry and delineate the importance of the stiffness of the test fixture on the stresses in the significant section of the specimen. An Arcan loading fixture was designed with the capability of loading of flat laminate specimens under various combinations of in-plane tensile and shear stresses. Quasi-static and fatigue tests were conducted with four different specimen configurations containing either 0, 30, 45 or 90o fiber orientations in the outer layers. The quasi-static strength followed a quadratic failure envelope on a normal stress-shear stress plane. Biaxial fatigue tests were conducted under combined tensile and shear stresses to determine the effect of biaxiality on the fatigue performance of the laminate. Development of fatigue damage under biaxial loading was also studied. A new fatigue life prediction model was proposed that can be used to account for the effect of biaxiality on the fatigue life of fiber reinforced polymer laminates.Ph.D.Automotive Systems Engineering, College of Engineering and Computer ScienceUniversity of Michigan-Dearbornhttp://deepblue.lib.umich.edu/bitstream/2027.42/136076/1/Mandapati Final Approved Dissertation.pdfDescription of Mandapati Final Approved Dissertation.pdf : Dissertatio

The Role and Mechanism of Action of BRK in Tamoxifen-resistant Breast Cancer

The anti-Estrogen Receptor (ER) therapy Tamoxifen has historically been used as a first -line treatment against ER-positive breast cancer. However, 30% of Tamoxifen-treated tumours develop resistance against the drug (TamR). Breast Tumour Kinase (BRK), a tyrosine kinase, presents itself as a possible target to combat TamR resistance as it drives tumourigenesis in breast cancer cells. Previous research has shown that BRK knockdown re-sensitizes TamR cells to the drug, though the mechanisms behind BRK’s functioning in TamR have yet to be elucidated. To address this, I used a global phosphoproteomics approach to compare MCF7 cell lines, that differed in their sensitivity to Tamoxifen, and TamR T47D cells, that differed in BRK expression, and found a total of 1048 differentially expressed phosphopeptides. Pathway analysis revealed overrepresentation of the IGFR and insulin receptor signaling in both MCF7 and T47D TamR cells as well as when BRK was knocked down in T47D TamR cells. Specifically, BRK knockdown resulted in the inhibition of Insulin Receptor Substrate-1 (IRS1) through the hyperphosphorylation of the S1101 site and the hypophosphorylation of the Y896. Subsequent RT-PCR and ChIP-qPCR analyses revealed that both BRK knockdown and inhibition reduced downstream changes in cyclin D1 gene expression mediated by IRS1. To further identify BRK-specific targets, phosphotyrosine-enriched phosphoproteomics analysis was also conducted, comparing T47D Parental, T47D TamR and T47D TamR BRK knockdown cells. Out of 6492 phosphosites identified, 118 high -confidence phosphotyrosine sites were analyzed for significant changes in phosphorylation levels to identify differentially regulated pathways in TamR versus Parental cells and changes in these pathways when BRK is knocked down in TamR. Total proteomics analysis was then used to calculate the phosphorylation levels of these peptides relative to their total levels. Through this, I identified potential BRK-specific targets involved in TamR such as CDK1, GSK3-beta and catenin delta-1. Of these targets, I was able to validate that both the knockdown and inhibition of BRK in TamR cells resulted in the hypophosphorylation of both CDK1 and catenin delta-1 at the Y15 and Y904 phosphosites respectively. Overall, these findings indicate that BRK helps regulate TamR through its interaction with signaling intermediaries in the IGFR/insulin receptor signaling pathway

Communication Strategies for Building Climate-Smart Farming Communities

Farming communities across the globe, especially in the drylands of Asia and Africa, are already facing the effects of climate change. With droughts, unseasonal rains and unpredictable dry spells becoming more frequent, reaching farmers with timely climate information and cropping advice is crucial as are coping strategies to face future climate shocks. There is also an urgent need to create, among farming communities, an awareness on reducing agricultural greenhouse gas emissions (GHGs) which contribute to a third of all human-generated GHGs. For this, holistic communication strategies that use best available technologies and target not just farmers but link all the stakeholders along the agricultural value chain are needed. Working for over 40 years in the semi-arid tropics with varied partners, ICRISAT has developed resilient dryland crops and a pool of climate-smart technologies besides researching on biofuels as alternatives for fossil fuels. These technologies are being implemented in locations across sub-Saharan Africa and Southeast Asia. This article records the various approaches used, lessons learnt and successes achieved in building climate smart villages/communes that restore/nurture the environment, use scientific innovations and climate information for cropping decisions, diversify livelihoods, link to markets, influence policy makers and ultimately make agriculture profitable

Field-level rice yield estimations under different farm practices using the crop simulation model for better yield

Crop yield estimation is essential for decision-making systems and insurance policy makers. Numerous methodologies for yield estimation have been developed, encompassing crop models, remote sensing techniques, and empirical equations. Each approach holds unique limitations and advantages. The primary aim of this study was to assess the accuracy of the DSSAT (Decision Support System for Agro Technology Transfer) model in predicting rice yields and LAI (Leaf Area Index) across various management methods. Additionally, the study sought to identify the optimal management practice for attaining higher yields. Crop models facilitate the expeditious evaluation of management strategies aimed at improving crop yield and analyzing the balance between production, resource efficiency, and environmental impacts. The study region selected for analysis is Karimnagar district of Telangana state. DSSAT has been chosen as the preferred tool due to its high efficiency in evaluating crop yield. The model's simulated yield was compared to the observed yield obtained from crop-cutting experiments. The results indicate a correlation of 0.81 and 0.85 between observed and simulated yields, as well as between model LAI and yield. An observation was made regarding a discrepancy between predicted and actual yields, which can be attributed to biotic stress. However, it should be noted that the current model does not account for this factor. The observed average yield was 5200 kg ha-1, whereas the projected yield was 5400 kg ha-1. The findings indicate that the model's performance is influenced by both the timing of sowing and the amount of nitrogen applied. The findings indicate that the DSSAT model has demonstrated a high level of accuracy in predicting both yields and leaf area index (LAI) across various management strategies. This study showcases the potential use of crop simulation models as a technology-driven tool to identify the most effective management strategies for rice production

An FPGA/MPSoC Based Low Latency Onboard SAR Processor

This paper describes the concept and prototype implementation of a low latency spaceborne onboard Synthetic Aperture Radar (SAR) processor runing on a Multi-Processor-System-On-Chip (MPSoC) computing device combining an ARM processor and a Field-Programmable-Gate-Array (FPGA). The SAR processor is designed to generate SAR imagery from TerraSAR-X stripmap data for subsequent ship detection and sea state determination. Low latency data processing is a key development goal. Currently, a raw data block of 8k×32k samples, covering 375 km^2 to 500 km^2 , is focused on the hardware within 4 s. Together with an attached level-2 ship detection, wind, and sea state processor, running on the same device, a SAR data processing chain for generation of maritime alerts is formed. This chain is part of a larger prototype system being developed in the frame of the H2020 EO-ALERT project which further comprises an optical data chain, data compression/encryption, and scheduling on multiple reconfigurable MPSoC boards

Delineation of the ancestral tus-dependent replication fork trap

In Escherichia coli, DNA replication termination is orchestrated by two clusters of Ter sites forming a DNA replication fork trap when bound by Tus proteins. The formation of a ‘locked’ Tus– Ter complex is essential for halting incoming DNA replication forks. However, the absence of replication fork arrest at some Ter sites raised questions about their significance. In this study, we examined the genome-wide distribution of Tus and found that only the six innermost Ter sites (TerA–E and G) were significantly bound by Tus. We also found that a single ectopic insertion of TerB in its non-permissive orientation could not be achieved, advocating against a need for ‘back-up’ Ter sites. Finally, examination of the genomes of a variety of Enterobacterales revealed a new replication fork trap architecture mostly found outside the Enterobacteriaceae family. Taken together, our data enabled the delineation of a narrow ancestral Tus-dependent DNA replication fork trap consisting of only two Ter sites

Copper promoted synthesis of tetrazoles and further conversion into diaryl tetrazoles through C-N cross-coupling approach

313-324Efficient tandem three component method has been demonstrated for the synthesis of substituted tetrazoles under mild reaction conditions using copper catalysis. Green solvent DMSO has been utilized and the reaction has been carried out at room temperature which establishes that our method is green synthetic approach. Variety of substrates readily undergo the optimized reaction conditions to provide their respective target products in good to excellent yields. In addition we have observed regioselective compounds depending on the substituents of phenyl ring. All the reactions are rapid, facile and are accomplished at room temperature. The reactions are of general application, clean and efficient. Furthermore we have confirmed that no other by-products could be identified during our experimental reaction process. In addition, C-N cross-coupling have been developed with phenyltetrazoleamines and aryl iodide under moderate reaction conditions

Forced Symmetry Breaking from SO(3) to SO(2) for Rotating Waves on the Sphere

We consider a small SO(2)-equivariant perturbation of a reaction-diffusion system on the sphere, which is equivariant with respect to the group SO(3) of all rigid rotations. We consider a normally hyperbolic SO(3)-group orbit of a rotating wave on the sphere that persists to a normally hyperbolic SO(2)-invariant manifold $M(\epsilon)$. We investigate the effects of this forced symmetry breaking by studying the perturbed dynamics induced on $M(\epsilon)$ by the above reaction-diffusion system. We prove that depending on the frequency vectors of the rotating waves that form the relative equilibrium SO(3)u_{0}, these rotating waves will give SO(2)-orbits of rotating waves or SO(2)-orbits of modulated rotating waves (if some transversality conditions hold). The orbital stability of these solutions is established as well. Our main tools are the orbit space reduction, Poincare map and implicit function theorem

Selective and potent urea inhibitors of Cryptosporidium parvum inosine 5’-monophosphate dehydrogenase

Cryptosporidium parvum and related species are zoonotic intracellular parasites of the intestine. Cryptosporidium is a leading cause of diarrhea in small children around the world. Infection can cause severe pathology in children and immunocompromised patients. This waterborne parasite is resistant to common methods of water treatment and therefore a prominent threat to drinking and recreation water even in countries with strong water safety systems. The drugs currently used to combat these organisms are ineffective. Genomic analysis revealed that the parasite relies solely on inosine-5?-monophosphate dehydrogenase (IMPDH) for the biosynthesis of guanine nucleotides. Herein, we report a selective urea-based inhibitor of C. parvum IMPDH (CpIMPDH) identified by high-throughput screening. We performed a SAR study of these inhibitors with some analogues exhibiting high potency (IC50 1000-fold versus human IMPDH type 2 and good stability in mouse liver microsomes. A subset of inhibitors also displayed potent antiparasitic activity in a Toxoplasma gondii model