Gate Driver Circuit Design, PWM signal generation using FEZ Panda III and Arduino for Inverter

This paper presents the gate driver circuit design and PWM signal generation using FEZ panda III and Arduino boards for Inverter. FEZ panda III works on .net micro framework and all its programming, debugging features are available through Microsoft’s Visual studio whereas Arduino features are available through Arduino software. Inverters are used in various applications like in motor drives and solar and wind power applications. This paper is commenced by basic understanding of need of gate driver circuit for inverter and different types of PWM techniques for generating gate signals for inverter. Simulation of SPWM inverter in both open loop and closed loop operation is done and its respective gate voltage waveforms are studied and later hardware implementation of gate driver circuit using TLP250H IC is carried out and gate voltages at different duty cycles is studied with the help of FEZ Panda III and Arduino boards

Tumour Cannabinoid CB1 Receptor and Phosphorylated Epidermal Growth Factor Receptor Expression Are Additive Prognostic Markers for Prostate Cancer

BACKGROUND: In cultured prostate cancer cells, down-regulation of epidermal growth factor receptor (EGFR) has been implicated in mediating the antiproliferative effect of the endogenous cannabinoid (CB) ligand anandamide. Using a well-characterised cohort of prostate cancer patients, we have previously reported that expression levels of phosphorylated EGFR (pEGFR-IR) and CB(1) receptor (CB(1)IR) in tumour tissue at diagnosis are markers of disease-specific survival, but it is not known whether the two markers interact in terms of their influence on disease severity at diagnosis and disease outcome. METHODOLOGY/PRINCIPAL FINDINGS: Data from a cohort of 419 patients who were diagnosed with prostate cancer at transurethral resection for voiding difficulties was used. Scores for both tumour CB(1)IR and pEGFR-IR were available in the database. Of these, 235 had been followed by expectancy until the appearance of metastases. For patients scored for both parameters, Cox proportional-hazards regression analyses using optimal cut-off scores indicated that the two measures provided additional diagnostic information not only to each other, but to that provided by the tumour stage and the Gleason score. When the cases were divided into subgroups on the basis of these cut-off scores, the patients with both CB(1)IR and pEGFR-IR scores above their cut-off had a poorer disease-specific survival and showed a more severe pathology at diagnosis than patients with high pEGFR-IR scores but with CB(1)IR scores below the cut-off. CONCLUSIONS/SIGNIFICANCE: These data indicate that a high tumour CB(1) receptor expression at diagnosis augments the deleterious effects of a high pEGFR expression upon disease-specific survival

A neoclerodane orthoester and other new neoclerodane diterpenoids from Teucrium yemense chemistry and effect on secretion of insulin

Teucrium yemense, a medicinal plant commonly grown in Saudi Arabia and Yemen, is traditionally used to treat infections, kidney diseases, rheumatism, and diabetes. Extraction of the dried aerial parts of the plant with methanol, followed by further extraction with butanol and chromatography, gave twenty novel neoclerodanes. Their structures, relative confgurations and some conformations were determined by MS and 1-D and 2-D NMR techniques. Most were fairly conventional but one contained an unusual stable orthoester, one had its (C-16)–(C-13)–(C-14)–(C-15) (tetrahydro)furan unit present as a succinic anhydride and one had a rearranged carbon skeleton resulting from ring-contraction to give a central octahydroindene bicyclic core, rather than the usual decalin. Mechanisms are proposed for the biosynthetic formation of the orthoester and for the ring-contraction. Four novel neoclerodanes increased the glucose-triggered release of insulin from isolated murine pancreatic islets by more than the standard drug tolbutamide, showing that they are potential leads for the development of new anti-diabetic drugs

Stimulation of insulin secretion by 5-methylcoumarins and its sulfur analogues isolated from Clutia lanceolata Forssk

Clutia lanceolata Forssk. (C. lanceolata) is a medicinal plant native to sub-Saharan Africa and the Arabian Peninsula. Phytochemical investigation of the aerial parts of C. lanceolata yielded twenty-one coumarins including methylthio and methylsulfinyl-coumarins. Thirteen of these compounds are reported here for the first time, named as cluteolin A to M. The remaining eight compounds are known but have not been associated previously with C. lanceolata. The structures of the undescribed compounds were elucidated from their 2D NMR and MS spectra. Single crystal X-ray analyses confirmed the structures of eleven compounds. As, in Saudi Arabian tradition, C. lanceolata has been reported to have anti-diabetic and anti-fungal properties, the coumarins were examined for their biological activity. Seven compounds strongly enhanced the glucose-triggered release of insulin by murine pancreatic islets, with two compounds showing more than two-fold enhancement of insulin secretion, compared with the standard drug glimepiride

Comparison study of preferential oxidation of CO over nanocrystalline Cu/CeO2 catalysts synthesized by different preparation methods

121-126Preferential oxidation of carbon monoxide in presence of excess hydrogen is a promising alternative to restrict the CO deposition in the Pt-anode in the practical polymer electrolyte membrane fuel cell application. In the present work, nanocrystalline copper-ceria catalysts have been synthesized by hydrothermal method, wet impregnation method and urea nitrate combustion method. Their characterizations have been carried out by using X-ray diffraction, transmission electron microscopy, X . ray photoelectron spectroscopy- It has been found that Cu2+ replaced Ce4+ in cerium oxide, creating oxygen vacancy. The formation of more nano-sized CeO2 leads to more oxygen vacancies in CeO2 through the formation of interfacial Cu1+ ions, which also enhances the CO oxidation activity. Among the synthesized Cu-CeO2 catalysts, the catalyst prepared by hydrothermal method have shown both CO conversion andC O2 selectivity as 100% towards CO oxidation at 373 K in the presence of excess H2 making this catalyst viable for practical fuel cell application.

Neoclerodane Diterpenoids from Reehal Fatima, <i>Teucrium yemense</i>

<i>Teucrium yemense</i> (Defl), locally known as Reehal Fatima, is a medicinal plant commonly grown in Saudi Arabia and Yemen. Phytochemical investigation of the aerial parts of <i>T. yemense</i> yielded six new neoclerodane diterpenoids, namely fatimanol A–E (<b>1</b>, <b>2</b>, <b>3</b>, <b>5</b>, and <b>6</b>) and fatimanone (<b>4</b>), and the known teulepicephin (<b>7</b>). As both the <i>Teucrium</i> genus and the related <i>Lamiaceae</i> family have previously been widely reported to possess anthelmintic and antimicrobial activities, the structural and biological characterization of the seven diterpenoids was pursued. The structures of the new compounds were elucidated from their 2D NMR and MS profiles and by comparison to related compounds. The structure of fatimanol D (<b>5</b>) was confirmed by X-ray crystallographic analysis. The new structures contribute to the breadth of knowledge of secondary metabolites in this genus

Imbalance of flight-freeze responses and their cellular correlates in the Nlgn3-/y rat model of autism

Abstract Background Mutations in the postsynaptic transmembrane protein neuroligin-3 are highly correlative with autism spectrum disorders (ASDs) and intellectual disabilities (IDs). Fear learning is well studied in models of these disorders, however differences in fear response behaviours are often overlooked. We aim to examine fear behaviour and its cellular underpinnings in a rat model of ASD/ID lacking Nlgn3. Methods This study uses a range of behavioural tests to understand differences in fear response behaviour in Nlgn3 −/y rats. Following this, we examined the physiological underpinnings of this in neurons of the periaqueductal grey (PAG), a midbrain area involved in flight-or-freeze responses. We used whole-cell patch-clamp recordings from ex vivo PAG slices, in addition to in vivo local-field potential recordings and electrical stimulation of the PAG in wildtype and Nlgn3 −/y rats. We analysed behavioural data with two- and three-way ANOVAS and electrophysiological data with generalised linear mixed modelling (GLMM). Results We observed that, unlike the wildtype, Nlgn3 −/y rats are more likely to response with flight rather than freezing in threatening situations. Electrophysiological findings were in agreement with these behavioural outcomes. We found in ex vivo slices from Nlgn3 −/y rats that neurons in dorsal PAG (dPAG) showed intrinsic hyperexcitability compared to wildtype. Similarly, stimulating dPAG in vivo revealed that lower magnitudes sufficed to evoke flight behaviour in Nlgn3 −/y than wildtype rats, indicating the functional impact of the increased cellular excitability. Limitations Our findings do not examine what specific cell type in the PAG is likely responsible for these phenotypes. Furthermore, we have focussed on phenotypes in young adult animals, whilst the human condition associated with NLGN3 mutations appears during the first few years of life. Conclusions We describe altered fear responses in Nlgn3 −/y rats and provide evidence that this is the result of a circuit bias that predisposes flight over freeze responses. Additionally, we demonstrate the first link between PAG dysfunction and ASD/ID. This study provides new insight into potential pathophysiologies leading to anxiety disorders and changes to fear responses in individuals with ASD