2,519 research outputs found

    Multi-parameter approach to R-parity violating SUSY couplings

    Full text link
    We introduce and implement a new, extended approach to placing bounds on trilinear R-parity violating couplings. We focus on a limited set of leptonic and semi-leptonic processes involving neutrinos, combining multidimensional plotting and cross-checking constraints from different experiments. This allows us to explore new regions of parameter space and to relax a number of bounds given in the literature. We look for qualitatively different results compared to those obtained previously using the assumption that a single coupling dominates the R-parity violating contributions to a process (SCD). By combining results from several experiments, we identify regions in parameter space where two or more parameters approach their maximally allowed values. In the same vein, we show a circumstance where consistency between independent bounds on the same combinations of trilinear coupling parameters implies mass constraints among slepton or squark masses. Though our new bounds are in most cases weaker than the SCD bounds, the largest deviations we find on individual parameters are factors of two, thus indicating that a conservative, order of magnitude bound on an individual coupling is reliably estimated by making the SCD assumption.Comment: 30 pages, 8 figures, 2 tables. Typos fixed, two references added and references updated. Eq. (41) removed, Eq. (40) and text modified. Published versio

    Seeing the halo rotation of nearby spiral galaxies using Planck data

    Get PDF
    The rotation of the galactic halos is a fascinating topic which is still waiting to be addressed. Planck data have shown the existence of a temperature asymmetry towards the halo of several nearby galaxies, such as M31, NGC 5128, M33, M81 and M82. However, the cause of this asymmetry is an open problem. A possibility to explain the observed effect relies on the presence of “cold gas clouds” populating the galactic halos, which may be the answer to the so-called missing baryon problem. Here, we present a technique to estimate an upper limit to the rotational velocity of the halo of some nearby spiral galaxies using both their dynamical masses and the Planck data

    Robust moving horizon state estimation for uncertain linear systems using linear matrix inequalities

    Get PDF
    This paper investigates the problem of state estimation for linear-time-invariant (LTI) discrete-time systems subject to structured feedback uncertainty and bounded disturbances. The proposed Robust Moving Horizon Estimation (RMHE) scheme computes at each sample time tight bounds on the uncertain states by solving a linear matrix inequality (LMI) optimization problem based on the available noisy input and output data. In comparison with conventional approaches that use offline calculation for the estimation, the suggested scheme achieves an acceptable level of performance with reduced conservativeness, while the online computational time is maintained relatively low. The effectiveness of the proposed estimation method is assessed via a numerical example

    Lepton Polarization Asymmetry in B l l(bar) decays in R-parity violating Minimal Supersymmetric Standard Model

    Full text link
    We study the implication of R-parity violating Rp Minimal Supersymmetric Standard Model (MSSM) model in lepton polarization asymmetry ALP in B l l(bar) decays . The analysis show that the ALP is significant in a certain phenomenological parametric region of Yukawa couplings. We have also placed indirect bounds on Lambda' lambda couplings as obtained from B t t(bar).Comment: 6 pages, 4 figures Changes of notation in Eq(8-11,17-19),Eq.20 adde

    Investigating processing window of Affinisol™ and Plasdone™ - S630 polymers during hot-melt extrusion (for 3D printing by fused deposition modelling)

    Get PDF
    There are numerous polymers that have been used commercially to produce pharmaceutical solid dispersions and solutions from hot melt extrusion. Affinisol™ (HPMC) and Plasdone™ S630 (PVP based co-povidone copolymer) have been used in the present work to determine the viable processing space with regards thermal and work input on a twin screw extruder. Processing viability has been determined by monitoring degradation, initially assessed by physical appearance and colour of the extrudates across the full operating range of a twin screw extruder. It has been found that the Affinisol™ had a relatively narrow viable operating window compared with the Plasdone™

    Assessment of Obesity, Dyslipidemia, Hyperglycemia, and Pro-Inflammatory Cytokines as Cardiovascular Disease Risk Factors in Acromegaly Patients

    Get PDF
    تعد أمراض القلب والأوعية الدموية واحدة من أكثر الأمراض المصاحبة المرتبطة بتضخم الأطراف انتشارًا ، وتحدث في 60 بالمائة من مرضى ضخامة الأطراف. يهدف البحث الى  تقييم العلاقة بين هرمون النمو والأنسولين شبيه عامل النمو -1 مع السمنة ,اضطراب الدهون ,ارتفاع السكر في الدم والسيتوكينات المؤيدة للالتهابات  (IL-2, IL-6, IL-10)كعامل خطر لاضطراب القلب والأوعية الدموية لدى مرضى ضخامة النهايات . اشتملت الدراسة على 80 شخصًا تم تقسيمهم إلى قسمين: 40 مريضًا من ضخامة النهايات و 40 شخصا سليما كمجموعة تحكم. أشارت النتائج إلى زيادة الوزن ، وارتفاع السكر في الدم ، وارتفاع ضغط الدم ، واضطراب الدهون ، وارتفاع مستويات الإنترلوكينات (2، 6، و 10) ، وأظهرت نتائج الارتباط ارتباطًا إيجابيًا معنويًا لكل من GH و IGF-1 مع كل من الوزن ، مؤشر كتلة الجسم ، ضغط الدم الانقباضي ، ضغط الدم الانبساطي ، FBS ، HbA1c ، الكوليسترول ، الدهون الثلاثية ، LDL ، IL6 ، IL2 ، ومؤشر تصلب الشرايين ، بينما يظهر فقط IGF-1 ارتباطًا معنويًا بـ. IL10. نستنتج أن المستويات المرتفعة من IL2 و IL6 و IL 10 وارتباطها مع كل من GH و IGF-1 بالإضافة إلى اضطراب الدهون وارتفاع السكر في الدم ومعايير ارتفاع ضغط الدم لمرضى ضخامة النهايات تقترح ضرورة  المسح السريري لاضطراب القلب والأوعية الدموية لمرضى ضخامة الاطراف.Cardiovascular disease is one of the most common comorbidities associated with enlarged extremities, occurring in 60 % of patients with acromegaly. The aim of this study is to evaluate the relationship of growth hormone and insulin such as growth factor-1 with obesity, dyslipidemia, hyperglycemia, and pro-inflammatory cytokines (IL-2, IL-6, IL-10), as risk factors for cardiovascular disorder in acromegaly patients. Eighty subjects were included and categorized into two groups: 40 acromegaly patients and 40 of the control group. The results indicated weight excess, hyperglycemia, hypertension, lipid disorder, and elevated levels of interleukins (2, 6, and 10). The correlation of both GH and IGF-1 with each of weight, BMI, systolic blood pressure, diastolic blood pressure, FBS, HbA1c, cholesterol, triglyceride, LDL, IL6, IL2, and the atherogenic index was found to be positive and significant. Meanwhile, only IGF-1 was significantly correlated with IL10. We conclude that elevated levels of IL2, IL6, IL 10 and their association with both GH and IGF-1 as well as to lipid disorder, hyperglycemia, and hypertension criteria of acromegaly patients are all risk factors for cardiovascular disease, suggesting the necessary clinical examination for cardiovascular disorder in patients with acromegaly patients

    Chiral Plaquette Polaron Theory of Cuprate Superconductivity

    Get PDF
    Ab-initio density functional calculations on explicitly doped La(2-x)Sr(x)CuO4 find doping creates localized holes in out-of-plane orbitals. A model for superconductivity is developed based on the assumption that doping leads to the formation of holes on a four-site Cu plaquette composed of the out-of-plane A1 orbitals apical O pz, planar Cu dz2, and planar O psigma. This is in contrast to the assumption of hole doping into planar Cu dx2-y2 and O psigma orbitals as in the t-J model. Interaction of holes with the d9 spin background leads to chiral polarons with either a clockwise or anti-clockwise charge current. When the polaron plaquettes percolate through the crystal at x~0.05 for LaSrCuO, a Cu dx2-y2 and planar O psigma band is formed. Spin exchange Coulomb repulsion with chiral polarons leads to D-wave superconductivity. The equivalent of the Debye energy in phonon superconductivity is the maximum energy separation between a chiral polaron and its time-reversed partner. An additive skew-scattering contribution to the Hall effect is induced by chiral polarons and leads to a temperature dependent Hall effect that fits the measured values for LaSrCuO. The integrated imaginary susceptibility satisfies omega/T scaling due to chirality and spin-flip scattering of polarons along with a uniform distribution of polaron energy splittings. The derived functional form is compatible with experiments. The static spin structure factor is computed and is incommensurate with a separation distance from (pi,pi) given by ~(2pi)x. Coulomb scattering of the x2-y2 band with polarons leads to linear resistivity. Coupling of the x2-y2 band to the undoped Cu d9 spins leads to the ARPES pseudogap and its doping and temperature dependence.Comment: 32 pages, 17 figure

    Chandra Reveals Heavy Obscuration and Circumnuclear Star Formation in Seyfert 2 Galaxy NGC 4968

    Full text link
    We present the Chandra imaging and spectral analysis of NGC 4968, a nearby (z = 0.00986) Seyfert 2 galaxy. We discover extended (\sim1 kpc) X-ray emission in the soft band (0.5 - 2 keV) that is neither coincident with the narrow line region nor the extended radio emission. Based on spectral modeling, it is linked to on-going star formation (\sim2.6-4 M_{\sun} yr1^{-1}). The soft emission at circumnuclear scales (inner \sim400 pc) originates from hot gas, with kT \sim 0.7 keV, while the most extended thermal emission is cooler (kT \sim 0.3 keV). We refine previous measurements of the extreme Fe Kα\alpha equivalent width in this source (EW = 2.51.0+2.6^{+2.6}_{-1.0} keV), which suggests the central engine is completely embedded within Compton-thick levels of obscuration. Using physically motivated models fit to the Chandra spectrum, we derive a Compton-thick column density (NH>1.25×1024N_{\rm H} > 1.25\times10^{24} cm2^{-2}) and an intrinsic hard (2-10 keV) X-ray luminosity of \sim3-8×1042\times 10^{42} erg s1^{-1} (depending on the presumed geometry of the obscurer), which is over two orders of magnitude larger than that observed. The large Fe Kα\alpha EW suggests a spherical covering geometry, which could be confirmed with X-ray measurements above 10 keV. NGC 4968 is similar to other active galaxies that exhibit extreme Fe Kα\alpha EWs (i.e., >>2 keV) in that they also contain ongoing star formation. This work supports the idea that gas associated with nuclear star formation may increase the covering factor of the enshrouding gas and play a role in obscuring AGN.Comment: 11 pages, 8 figures, 4 tables. Accepted for publication in Ap
    corecore