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We show that the excess events observed in a number of recent LHC resonance searches can be simultaneously explained within a nonsupersymmetric left-right inverse seesaw model for neutrino masses with W_{R} mass around 1.9 TeV. The minimal particle content that leads to gauge coupling unification in this model predicts g_{R}≃0.51 at the TeV scale, which is consistent with data. The extra color singlet, SU(2)-triplet fermions required for unification can be interpreted as the dark matter of the Universe. Future measurements of the ratio of same-sign to opposite-sign dilepton events can provide a way to distinguish this scenario from the canonical cases of type-I and inverse seesaw, i.e., provide a measure of the relative magnitudes of the Dirac and Majorana masses of the right-handed neutrinos in the SU(2)_{R} doublet of the left-right symmetric model.
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We show that grand unified theories based on SO(10) generate quite naturally baryon number violating dimension seven operators that violate B-L, and lead to novel nucleon decay modes such as nâe(-)K(+), e(-)π(+) and pâνπ(+). We find that in two-step breaking schemes of nonsupersymmetric SO(10), the partial lifetimes for these modes can be within reach of experiments. The interactions responsible for these decay modes also provide a new way to understand the origin of matter in the Universe via the decays of grand unified theory (GUT) scale scalar bosons of SO(10). Their (B-L)-violating nature guarantees that the GUT scale induced baryon asymmetry is not washed out by the electroweak sphaleron interactions. In minimal SO(10) models this asymmetry is closely tied to the masses of quarks, leptons and the neutrinos.
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Extending the minimal supersymmetric standard model to explain small neutrino masses via the inverse seesaw mechanism can lead to a new light supersymmetric scalar partner which can play the role of inelastic dark matter (IDM). It is a linear combination of the superpartners of the neutral fermions in the theory (the light left-handed neutrino and two heavy standard model singlet neutrinos) which can be very light with mass in ~5-20 GeV range, as suggested by some current direct detection experiments. The IDM in this class of models has keV-scale mass splitting, which is intimately connected to the small Majorana masses of neutrinos. We predict the differential scattering rate and annual modulation of the IDM signal which can be testable at future germanium- and xenon-based detectors.
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STUDY DESIGN: To visualize residual urine in a bladder using a regular Foley catheter and then using a modified Foley catheter. OBJECTIVES: To determine whether a modified Foley catheter eliminates or reduces a catheter-associated deposition of residual urine around the balloon and whether this reduction eliminates catheter leakage. SETTINGS: A patient with chronic spinal cord injury using a Foley catheter and experiencing significant refractory urine leakage around the catheter. METHODS: The design of a Foley catheter and the way it drains lead to the constant presence of small amounts of residual urine at the base, surrounding the balloon. The Foley catheter was modified using a cook catheter punch to make two extra holes just below the balloon. RESULTS: A cystogram of an unmodified Foley catheter showed the presence of residual urine around the Foley balloon. A cystogram of a modified Foley catheter eliminated this residual urine around the balloon. After the modification there was no more leakage around the Foley catheter. CONCLUSION: Modification of the catheter, as described, eliminated the residual urine around the catheter balloon and eliminated clinical urine leakage around the Foley catheter.
Assuntos
Cateteres de Demora , Traumatismos da Medula Espinal/complicações , Cateterismo Urinário/métodos , Transtornos Urinários/etiologia , Transtornos Urinários/enfermagem , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
We present a simple extension of the minimal supersymmetric standard model which provides a unified picture of cosmological baryon asymmetry and dark matter. Our model introduces a gauge singlet field N and a color triplet field X which couple to the right-handed quark fields. The out-of-equilibrium decay of the Majorana fermion N mediated by the exchange of the scalar field X generates adequate baryon asymmetry for MN approximately 100 GeV and MX approximately TeV. The scalar partner of N (denoted N1) is naturally the lightest SUSY particle as it has no gauge interactions and plays the role of dark matter. The model is experimentally testable in (i) neutron-antineutron oscillations with a transition time estimated to be around 10(10)sec, (ii) discovery of colored particles X at LHC with mass of order TeV, and (iii) direct dark matter detection with a predicted cross section in the observable range.
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The PVLAS experiment has recently claimed evidence for an axionlike particle in the milli-electron-volt mass range with a coupling to two photons that appears to be in contradiction with the negative results of the CAST experiment searching for solar axions. The simple axion interpretation of these two experimental results is therefore untenable and it has posed a challenge for theory. We propose a possible way to reconcile these two results by postulating the existence of an ultralight pseudoscalar particle interacting with two photons and a scalar boson and the existence of a low scale phase transition in the theory.
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We present a new mechanism for generating the baryon asymmetry of the Universe directly in the decay of a singlet scalar field S(r) with a weak scale mass and a high dimensional baryon number-violating coupling. Unlike most currently popular models, this mechanism, which becomes effective after the electroweak phase transition, does not rely on the sphalerons for inducing a nonzero baryon number. CP asymmetry in S(r) decay arises through loop diagrams involving the exchange of W+/- gauge bosons and is suppressed by light quark masses, leading naturally to a value of eta(B) approximately 10(-10). The simplest realization of this idea which uses a six quark DeltaB=2 operator predicts colored scalars accessible to the CERN Large Hadron Collider and neutron-antineutron oscillation within reach of the next-generation experiments.
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We discuss a realistic high scale (nu(B-L) approximately 10(12) GeV) supersymmetric seesaw model based on the gauge group SU(2)L x SU(2)R x SU(4)c where neutron-antineutron oscillation can be in the observable range. This is contrary to the naive dimensional arguments which say that tau(N-N) is proportional to nu(B-L)5 and should therefore be unobservable for seesaw scale nu(B-L) > or = 10(5) GeV. Two reasons for this enhancement are (i) accidental symmetries which keep some of the diquark Higgs masses at the weak scale and (ii) a new supersymmetric contribution from a lower dimensional operator. The net result is that tau(N-N) is proportional to nu(B-L)2 nu(wk)3 rather than nu(B-L)5. The model also can explain the origin of matter via the leptogenesis mechanism and predicts light diquark states which can be produced at LHC.
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We show that in a class of minimal supersymmetric SO(10) models which have been found to be quite successful in predicting neutrino mixings, all proton decay modes can be suppressed by a particular choice of Yukawa textures. The required texture not only fits all lepton and quark masses as well as Cabibbo-Kobayashi-Maskawa parameters, but it also predicts neutrino mixing parameter U(e3) and Dirac CP phase sin(/delta(MNS)/ to be 0.07-0.09 and 0.3-0.7, respectively.
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We discuss how CP symmetry can be broken geometrically through orbifold projections in hidden extra dimensions in the context of brane-bulk models for particle unifications. The CP violation arises from a crash between the geometry of the compactification and the original higher dimensional CP definition. We present toy models to illustrate the idea and suggest ways to incorporate it into more realistic models.
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Solar, atmospheric, and LSND neutrino oscillation results require a light sterile neutrino, nu(B), which can exist in the bulk of extra dimensions. Solar nu(e), confined to the brane, can oscillate in the vacuum to the zero mode of nu(B) and via successive Mikheyev-Smirnov-Wolfenstein transitions to Kaluza-Klein states of nu(B). This new way to fit solar data is provided by both low and intermediate string scale models. From average rates seen in the three types of solar experiments, the Super-Kamiokande spectrum is predicted with 73% probability, but dips characteristic of the 0.06 mm extra dimension should be seen in the SNO spectrum.
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Bovine grafts used in hemodialysis frequently need declotting. Success of the declotting procedure usually is dependent upon relieving outflow obstruction. Intraoperative angiography was done during 22 declotting procedures and outflow obstructions were detected in 14 grafts. Of these 5 grafts had clinically unsuspected clots, residual to the initial declotting attempt. Four grafts had stenotic areas at the site of the venous anastomosis, which were corrected subsequently by patch grafts. Two grafts had stenotic areas in the graft owing to an infolding of the intima covered with an organized blood clot. In 2 grafts the veins draining the grafts were stenotic for a considerable length and needed revision. In 1 graft there was stenotic change at the site of the arterial anastomosis, which required revision. Of the 14 grafts 11 have remained functioning for an additional 6 to 18 months after relief of obstruction.
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Derivação Arteriovenosa Cirúrgica , Bioprótese , Cuidados Intraoperatórios , Diálise Renal , Tromboembolia/diagnóstico por imagem , Adulto , Animais , Bovinos , Constrição Patológica , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Tromboembolia/etiologiaRESUMO
The relationship between serum lactic dehydrogenase (SLDH) values and renal allograft rejection was examined in the dog and in man. Nine dogs with renal allografts and four with autografts had similar maximal elevations of SLDH during the first five postoperative days (mean, 420 +/- 213 and 433 +/- 80 I.U. per liter, respectively). During rejection of the allografts between days 7 and 14 the maximum SLDH was 810 +/- 285 I.U. per liter, and in autografts the peak SLDH was 233 +/- 22 I.U. per liter (p less than 0.01). The isoenzyme pattern of maximum SLDH during rejection was prominent in LDH5 and corresponded with renal tissue LDH isoenzyme composition. In 93 episodes of initial acute human renal allograft rejection reactions, the SLDH peaked above 500 I.U. per liter in 23 cases and remained below 500 I.U. per liter in 70 cases. SLDH levels above 500 I.U. per liter were associated with complete rejection of the kidney in 91 percent of patients and SLDH levels persistently below 500 I.U. per liter corresponded with reversal of rejection reaction in 99 percent of patients (p less than 0.01). Marked SLDH elevation is associated with severe, usually complete renal allograft rejection and may be useful in identifying patients with irreversible rejection reactions.