Regioselective synthesis of some functionalized 3,4’-bis-(pyrazolyl)ketones and chemoselectivity in their reaction with hydrazine hydrate

A new enamino ester, (E)-ethyl 3-(dipropylamino)acrylate, was prepared and used for synthesis of various pyrazole derivatives, 4a-k and 5a-d. Other new enaminone, (E)-ethyl 3-(3-(dimethylamino)acryloyl)-1-(4-nitrophenyl)-1H-pyrazole-4-carboxylate (8), was also prepared from compound 4a and utilized as precursor for synthesis of different functionalized 3,4'-bis-pyrazolyl ketones 9a-c, 10a-c. The site selectivity in hydrazinolysis of the latter was studied. The structures of the products namely pyrazolo[3,4-d]pyridazine derivatives 11(13) were confirmed by spectral and elemental analyses and by alternate unambiguous synthesis

Spectral function at high missing energies and momenta

The nuclear spectral function at high missing energies and momenta has been determined from a self-consistent calculation of the Green's function in nuclear matter using realistic nucleon-nucleon interactions. The results are compared with recent experimental data derived from ($e,e'p$) reactions on $^{12}C$. A rather good agreement is obtained if the Green's functions are calculated in a non-perturbative way.Comment: 10 pages, 3 figure

Properties of asymmetric nuclear matter in different approaches

Properties of asymmetric nuclear matter are derived from various many-body approaches. This includes phenomenological ones like the Skyrme Hartree-Fock and relativistic mean field approaches, which are adjusted to fit properties of nuclei, as well as more microscopic attempts like the Brueckner-Hartree-Fock approximation, a self-consistent Greens function method and the so-called $V_{lowk}$ approach, which are based on realistic nucleon-nucleon interactions which reproduce the nucleon-nucleon phase shifts. These microscopic approaches are supplemented by a density-dependent contact interaction to achieve the empirical saturation property of symmetric nuclear matter. The predictions of all these approaches are discussed for nuclear matter at high densities in $\beta$-equilibrium. Special attention is paid to behavior of the isovector component of the effective mass in neutron-rich matter.Comment: 16 pages, 7 figure

First measurement of the spectral function at high energy and momentum in medium-heavy nuclei

The experiment E97-006 was performed at Jefferson Lab to measure the momentum and energy distribution of protons in the nucleus far from the region of the (approximate) validity of the mean field description, i.e. at high momentum and energies. The occurrence of this strength is long known from occupation numbers less than one. In the experiment reported here this strength was directly measured for the first time. The results are compared to modern many-body theories. Further the transparency factor of C12 was determined in the Q^2-region of 0.6 to 1.8 (GeV/c)^2.Comment: Proceeding for Fourth International Workshop on Neutrino-Nucleus Interactions in the Few-GeV Region 26.-29. Sept. 2005, Okayam

Effective mass splitting of neutron and proton and isospin emission in heavy-ion collisions

Within the framework of an isospin and momentum dependent transport model, the emissions of isospin particles (nucleons and light clusters) squeezed out in heavy-ion collisions are investigated as probes of the poorly known symmetry energy at high baryon density. Two different mass splittings of neutrons and protons in nuclear medium as $m_{n}^{\ast}>m_{p}^{\ast}$ and $m_{n}^{\ast}<m_{p}^{\ast}$ are used in the model and their influence on the isospin emission in heavy-ion collisions is discussed thoroughly. The competition between the stiffness and the momentum dependence of the symmetry potential on reaction dynamics are compared and systematically analyzed. It is found that the difference of the neutron and proton directed flows and the transverse momentum distribution of the neutron/proton ratio are sensitive to the stiffness of the symmetry energy, which can not be changed with the controversial effective mass splitting. The elliptic flows of free nucleons at high transverse momentum within mid-rapidity emission are a promising observable as distinguishing the nucleon effective mass splitting.Comment: 16 pages, 7 figure

Overall PAPR Reduction for MIMO OFDM Systems

Abstract Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) systems have been receiving a great attention as one of the solutions for achieving high speed, efficient, and high quality of service wireless communications. However, the main drawback of MIMO OFDM systems is high Peak to Average Power Ratio (PAPR) because of its sensitivity to the nonlinear distortions introduced by nonlinear devices. In MIMO OFDM systems, a straightforward way for PAPR reduction is to apply existing techniques separately on each transmit antenna. Therefore, a higher overall PAPR is obtained with increasing the number of transmit antennas. In this paper, Partial Transmit Sequences (PTS) technique is modified with different circular shifting approaches. They exploit the extra degree of freedom provided by the transmit antenna array to reduce the overall PAPR even with increasing the number of transmit antennas

Novel Trajectories of Bromocriptine Antidiabetic Action: Leptin-IL-6/ JAK2/p-STAT3/SOCS3, p-IR/p-AKT/GLUT4, PPAR-γ/Adiponectin, Nrf2/PARP-1, and GLP-1

Bromocriptine (BC), a sympatholytic dopaminergic D2 receptor agonist, has been comprehensively used in clinic to treat Parkinson’s disease (PD) and prolactinomas. Besides, BC represents a novel therapeutic option in type 2 diabetes (T2DM); however, the precise mechanisms are not completely unveiled. Hence, the objective of the current work is to clarify the potential molecular pathways of the insulin sensitizing effect of BC in the skeletal muscle of diabetic rats and to evaluate its possible interaction with sitagliptin (SG) as an add-on therapy. Here experimental model impersonates unhealthy dietary habit and T2DM was adopted, in which rats were fed high caloric diet of fat and fructose for 6 weeks followed by a single sub-diabetogenic dose of streptozotocin (STZ) (35 mg/kg; HF/Fr/STZ). Diabetic rats were treated with BC, SG at two dose levels (SG10 and SG20) and combination of BC + SG10 for 2 weeks. BC successfully corrected glucose/lipid profile, as well as leptin and GLP-1. On the muscular molecular level, BC curtailed the inflammatory signal IL-6/JAK2/p-STAT3/SOCS3, while enhanced the PPAR-γ/adiponectin signaling, resulting in activation of the insulin signaling pathway (p-IR/p-AKT/GLUT4). Moreover, BC confirmed its antioxidant capabilities by altering Nrf2 and PARP-1; the study also highlighted novel mechanisms for SG as well. On almost all tested parameters/pathways, the combination regimen surpassed each drug alone to reach a comparable level to the high dose of SG. In conclusion, our finding shed some light on novel anti-diabetic mechanisms of BC. The study also points to the potential use of BC as an adds-on to standard anti-diabetic therapies

Endozoochory by goats of two invasive weeds with contrasted propagule traits

Invasive plants have very important ecological and socioeconomic impacts. Producing and dispersing many viable seeds are key plant functional traits for invaders. Ungulate grazing plays an important role in the endozoochorous seed dispersal within grasslands and rangelands. Grazing can be applied as a practical and economical control method for plant invasions. We analyzed the effects of seed passage through the goat digestive system on the germination and viability for Sorghum halepense and Malva parviflora, common invasive species with contrasted propagules and seed traits. Both studied species produced seeds able to survive, in a small percentages (c. 0.80-1.70%), after being eaten by goats. Most of the seeds (c. 40-55%) of both species were retrieved between 24-48 h after ingestion. Goat passage provoked a decrease (> 60%) in the germination percentage and seed viability of S. halepense that was higher with longer gut retention times. In M. parviflora, the goat gut passage did not break its primary physical dormancy, since no retrieved seed germinated with similar viability as the uneaten seeds (c. 90%). In view of our results, goat grazing can be applied as a useful method to control S. halepense and M. parviflora invasions. Goats should be kept in corrals for at least 4 days after grazing to prevent transferring viable seeds to uninfected areas.Deanship of Scientific Research King Khalid University R.G.P.1/210/4