2,852 research outputs found
On the ternary complex analysis and its applications
Previouly a possible extension of the complex number, together with its
connected trigonometry was introduced. In this paper we focuss on the simplest
case of ternary complex numbers. Then, some types of holomorphicity adapted to
the ternary complex numbers and the corresponding results upon integration of
differential forms are given. Several physical applications are given, and in
particuler one type of holomorphic function gives rise to a new form of
stationary magnetic field. The movement of a monopole type object in this field
is then studied and shown to be integrable. The monopole scattering in the
ternary field is finally studied.Comment: LaTeX 28 page
Nicht-minimale Varianten des Seesaw-Mechanismus als Erweiterung des Standardmodells
We study non-minimal variants of the seesaw mechanism, especially of the type I and the double seesaw mechanism, in correlation with a singular Majorana mass term in the neutrino mass matrix. Also we demonstrate that in the inverse seesaw mechanism a “pseudo-singular” structure for the neutrino mass matrixcan be realized. It is further shown that in all scenarios under consideration active neutrino masses at the compulsory eV scale can be obtained in principle. By analyzing the eigenvalue and mass scale structure of the neutrino mass matrix in the singular double seesaw we find scenarios that feature eV, keV and MeV to GeV sterile neutrinos.
Real-time pair-feeding of animals
Automatic pair-feeding system was developed which immediately dispenses same amount of food to control animal as has been consumed by experimental animal that has free access to food. System consists of: master feeding system; slave feeding station; and control mechanism. Technique performs real time pair-feeding without attendant time lag
Automatic real-time pair-feeding system for animals
A pair feeding method and apparatus are provided for experimental animals wherein the amount of food consumed is immediately delivered to a normal or control animal so that there is a qualitative, quantitative and chronological correctness in the pair feeding of the two animals. This feeding mechanism delivers precisely measured amounts of food to a feeder. Circuitry is provided between master and slave feeders so that there is virtually no chance of a malfunction of the feeding apparatus, causing erratic results. Recording equipment is also provided so that an hourly record is kept of food delivery
Ultracold heteronuclear molecules in a 3D optical lattice
We report on the creation of ultracold heteronuclear molecules assembled from
fermionic 40K and bosonic 87Rb atoms in a 3D optical lattice. Molecules are
produced at a heteronuclear Feshbach resonance both on the attractive and the
repulsive side of the resonance. We precisely determine the binding energy of
the heteronuclear molecules from rf spectroscopy across the Feshbach resonance.
We characterize the lifetime of the molecular sample as a function of magnetic
field and measure between 20 and 120ms. The efficiency of molecule creation via
rf association is measured and is found to decrease as expected for more deeply
bound molecules.Comment: 4 pages, 4 figure
Minimal Conformal Extensions of the Higgs Sector
In this work we find the minimal extension of the Standard Model's Higgs sector which can lead to a light Higgs boson via radiative symmetry breaking and is consistent with the phenomenological requirements for a low-energy realization of a conformal theory. The model which turns out to be stable under renormalization group translations is an extension of the Standard Model by two scalar fields, one of which acquires a finite vacuum expectation value and therefore mixes into the physical Higgs. We find that the minimal model predicts a sizable amount of mixing which makes it testable at a collider. In addition to the physical Higgs, the theory's scalar spectrum contains one light and one heavy boson. The heavy scalar's properties render it a potential dark matter candidate
Dexamethasone induces apoptosis in pulmonary arterial smooth muscle cells
BACKGROUND: Dexamethasone suppressed inflammation and haemodynamic changes in an animal model of pulmonary arterial hypertension (PAH). A major target for dexamethasone actions is NF-κB, which is activated in pulmonary vascular cells and perivascular inflammatory cells in PAH. Reverse remodelling is an important concept in PAH disease therapy, and further to its anti-proliferative effects, we sought to explore whether dexamethasone augments pulmonary arterial smooth muscle cell (PASMC) apoptosis. METHODS: Analysis of apoptosis markers (caspase 3, in-situ DNA fragmentation) and NF-κB (p65 and phospho-IKK-α/β) activation was performed on lung tissue from rats with monocrotaline (MCT)-induced pulmonary hypertension (PH), before and after day 14–28 treatment with dexamethasone (5 mg/kg/day). PASMC were cultured from this rat PH model and from normal human lung following lung cancer surgery. Following stimulation with TNF-α (10 ng/ml), the effects of dexamethasone (10(−8)–10(−6) M) and IKK2 (NF-κB) inhibition (AS602868, 0–3 μM (0-3×10(−6) M) on IL-6 and CXCL8 release and apoptosis was determined by ELISA and by Hoechst staining. NF-κB activation was measured by TransAm assay. RESULTS: Dexamethasone treatment of rats with MCT-induced PH in vivo led to PASMC apoptosis as displayed by increased caspase 3 expression and DNA fragmentation. A similar effect was seen in vitro using TNF-α-simulated human and rat PASMC following both dexamethasone and IKK2 inhibition. Increased apoptosis was associated with a reduction in NF-κB activation and in IL-6 and CXCL8 release from PASMC. CONCLUSIONS: Dexamethasone exerted reverse-remodelling effects by augmenting apoptosis and reversing inflammation in PASMC possibly via inhibition of NF-κB. Future PAH therapies may involve targeting these important inflammatory pathways
Exceptional Laguerre and Jacobi polynomials and the corresponding potentials through Darboux-Crum Transformations
Simple derivation is presented of the four families of infinitely many shape
invariant Hamiltonians corresponding to the exceptional Laguerre and Jacobi
polynomials. Darboux-Crum transformations are applied to connect the well-known
shape invariant Hamiltonians of the radial oscillator and the
Darboux-P\"oschl-Teller potential to the shape invariant potentials of
Odake-Sasaki. Dutta and Roy derived the two lowest members of the exceptional
Laguerre polynomials by this method. The method is expanded to its full
generality and many other ramifications, including the aspects of generalised
Bochner problem and the bispectral property of the exceptional orthogonal
polynomials, are discussed.Comment: LaTeX2e with amsmath, amssymb, amscd 26 pages, no figure
Seismic site effects in a deep alluvial basin: numerical analysis by the boundary element method
The main purpose of the paper is the numerical analysis of seismic site
effects in Caracas (Venezuela). The analysis is performed considering the
boundary element method in the frequency domain. A numerical model including a
part of the local topography is considered, it involves a deep alluvial deposit
on an elastic bedrock. The amplification of seismic motion (SH-waves, weak
motion) is analyzed in terms of level, occurring frequency and location. In
this specific site of Caracas, the amplification factor is found to reach a
maximum value of 25. Site effects occur in the thickest part of the basin for
low frequencies (below 1.0 Hz) and in two intermediate thinner areas for
frequencies above 1.0 Hz. The influence of both incidence and shear wave
velocities is also investigated. A comparison with microtremor recordings is
presented afterwards. The results of both numerical and experimental approaches
are in good agreement in terms of fundamental frequencies in the deepest part
of the basin. The boundary element method appears to be a reliable and
efficient approach for the analysis of seismic site effects
The subperichondrial / subperiosteal dissection in preservation rhinoplasty: how histology can help us to perform better surgeries
Aim: The classical dissection plane in rhinoplasty is in the sub-SMAS plane with traumatic dissection
of tissues and as a result significant and prolonged postoperative edema, especially in the external approach.
A complete subperichondrial/periosteal route has been recently described. It seems to allow for simpler
postoperative follow-up than external or closed approach performed in the sub-SMAS plane. However, little
is known about the exact histological planes that are really dissected during surgery.
Material and methods: Histological examinations of 10 cadavers noses dissected in the so-called
subperichondrial/subperiosteal plane were performed.
Results: The subperichondrial plane is truly subperichondrial and consists in a dissection under the
chondrogenic layer of the perichondrium. Subperichondrial dissection necessitates sharp scrapping to separate
the cartilage from the chondrogenic layer. The perichondrium is naturally thicker on the dorsum, which
explains why it is easier to begin the dorsal dissection at the W point. Scroll cartilages are consistent and show
between 9 and 13 isolated cartilages, most of the time, 1 major and several minors cartilages. Optimal strategy
to ease the dissection is discussed
Conclusions: The subperichondrial/subperiosteal route, although necessitating significant dissection
of the teguments of the nasal pyramid, is respectful of the anatomy of the nasal pyramid. It allows minimal
traumatic maneuvers than in the sub-SMAS route, despite of the large dissection performed
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