Lasso Estimation of an Interval-Valued Multiple Regression Model

A multiple interval-valued linear regression model considering all the cross-relationships between the mids and spreads of the intervals has been introduced recently. A least-squares estimation of the regression parameters has been carried out by transforming a quadratic optimization problem with inequality constraints into a linear complementary problem and using Lemke's algorithm to solve it. Due to the irrelevance of certain cross-relationships, an alternative estimation process, the LASSO (Least Absolut Shrinkage and Selection Operator), is developed. A comparative study showing the differences between the proposed estimators is provided

Micro-structured Er 3+-tm 3+ Co-doped Tellurite Fiber For Broadband Optical Amplifier Around 1550nm

Micro-structured Er 3+-Tm 3+ co-doped tellurite fiber with three rings of holes was fabricated using a soft glass drawing tower by a stack-and-draw technique. Amplified spontaneous emission (ASE) around 1550nm band were observed when pumped with both, 980nm and 790nm, lasers.6314Russell, P., Photonic crystal fibers (2003) Science, 299, pp. 358-362Knight, J.C., Photonic crystal fibers (2003) Nature, 424, pp. 847-851Kumar, V.V.R.K., George, A.K., Reeves, W.H., Knight, J.C., Russell, P.St.J., Omenetto, F.G., Taylor, A.J., Extruded soft glass photonic crystal fiber for ultrabroad supercontinuum generation (2002) Opt. Exp, 10 (25), pp. 1520-1525Chillcce, E.F., Cordeiro, C.M.B., Barbosa, L.C., Cruz, C.H.B., Er 3+-Tm 3+ co-doped tellurite fibers for broadband optical fiber amplifier around 1550nm band (2006) Opt. Fiber Technol., 12, pp. 185-195Chillcce, E.F., Rodriguez, E., Neves, A.A.R., Moreira, W.C., Cesar, C.L., Barbosa, L.C., Cruz, C.H.B., Tellurite photonic crystal fiber by a stack-and-draw technique (2006) J. Non-cryst. Solids, , accepted to publicationWhite, T.P., McPhedran, R.C., De Sterke, C.M., Botten, L.C., Steel, M.J., Confinement losses in microstructured optical fibers (2001) Opt. Lett, 26 (21), pp. 1660-1663Barbosa, L.C., Cruz, C.H.B., Cesar, C.L., Cordeiro, C.M.B., Chillcce, E.F., Production process of tellurite glass tubes, capillaries and rods Brazilian pending Patent No 018050002734Chillcce, E.F., Cordeiro, C.M.B., Rodriguez, E., Cruz, C.H.B., Cesar, C.L., Barbosa, L.C., Tellurite photonic crystal fiber with Er 3+-Tm 3+ for broadband optical amplifier in 1550nm (2006) Proc. of SPIE, 6116, p. 61160

Antikaons and hyperons in nuclear matter with saturation

We evaluate the antikaon and hyperon spectral functions in a self-consistent and covariant many-body approach. The computation is based on coupled-channel dynamics derived from the chiral SU(3) Lagrangian. A novel subtraction scheme is developed that avoids kinematical singularities and medium-induced power divergencies all together. Scalar and vector mean fields are used to model nuclear binding and saturation. The effect of the latter is striking for the antikaon spectral function that becomes significantly more narrow at small momenta. Attractive mass shifts of about 30 and 40 MeV are predicted for the Lambda(1405) and Sigma(1385) resonances. Once scalar and vector mean fields for the nucleon are switched on the Lambda(1520) resonances dissolves almost completely in nuclear matter. All together only moderate attraction is predicted for the nuclear antikaon systems at saturation density. However, at larger densities we predict a sizable population of soft antikaon modes that arise from the coupling of the antikaon to a highly collective Lambda(1115) nucleon-hole state. This may lead to the formation of exotic nuclear systems with strangeness and antikaon condensation in compact stars at moderate densities.Comment: 49 pages, 13 figures, The revised manuscript contains additional material at twice nuclear saturation density. An unexpected and novel mechanism is unravelled that may have dramatic implications on the formation of exotic nuclear systems with strangeness and antikaon condensation in compact star

Wave profile and tide monitoring system for scalable implementation

Apresentação de Poster em conferência Nacional.Presentation of a wave profile and tide monitoring system, with low-cost and low-power pressure sensors connected to a datalogger in a wired or acustic network

Protection induced by simultaneous subcutaneous and endobronchial vaccination with BCG/BCG and BCG/adenovirus expressing antigen 85A against Mycobacterium bovis in cattle

The incidence of bovine tuberculosis (bTB) in the GB has been increasing since the 1980s. Immunisation, alongside current control measures, has been proposed as a sustainable measure to control bTB. Immunisation with Mycobacterium bovis bacillus Calmette-Guerin (BCG) has been shown to protect against bTB. Furthermore, much experimental data indicates that pulmonary local immunity is important for protection against respiratory infections including Mycobacterium tuberculosis and that pulmonary immunisation is highly effective. Here, we evaluated protection against M. bovis, the main causative agent of bTB, conferred by BCG delivered subcutaneously, endobronchially or by the new strategy of simultaneous immunisation by both routes. We also tested simultaneous subcutaneous immunisation with BCG and endobronchial delivery of a recombinant type 5 adenovirus expressing mycobacterial antigen 85A. There was significantly reduced visible pathology in animals receiving the simultaneous BCG/BCG or BCG/Ad85 treatment compared to naïve controls. Furthermore, there were significantly fewer advanced microscopic granulomata in animals receiving BCG/Ad85A compared to naive controls. Thus, combining local and systemic immunisation limits the development of pathology, which in turn could decrease bTB transmission

The accuracy of 99mTc-DTPA scintigraphy in the evaluation of acute renal graft complications

PURPOSE: Renal scintigraphy has been used for many years in the evaluation of renal transplants and can help in the diagnosis of graft complications, leading to prompt clinical management and preventing further deterioration of renal function. The purpose of this study was to evaluate the overall accuracy of renal scintigraphy with 99mTc-DTPA in the diagnosis of acute renal graft complications. MATERIALS AND METHODS: Seventy-six scintigraphic studies performed in 55 patients (ages ranging from 6 to 65 years), were reviewed. Scintigraphy results were compared to biopsies performed within 5 days of imaging. 99mTc-DTPA study was performed within a mean time of 19 days after kidney transplants. Dynamic images were performed in the anterior position of the abdomen and pelvis every 2 seconds for 80 seconds (flow phase) and every 15 seconds for 30 minutes (functional phase), after an intravenous injection of 370 MBq (10 mCi) of 99mTc-DTPA. RESULTS: The scintigraphic results were concordant with the biopsies in 86% of the cases studied. The sensitivities of renal scintigraphy for detection of acute tubular necrosis (ATN), acute rejection (AR) and cortical necrosis (CN) were 98%, 87% and 100%, respectively. Specificities and accuracies for detection of ATN, AR and CN were 89%, 86% and 100%, and 95%, 87% and 100%, respectively. CONCLUSION: Renal scintigraphy with 99mTc-DTPA showed a good overall accuracy in the detection of acute renal graft complications. It can be used as a reliable tool in the routine evaluation of these patients50751

Chaotic scalar fields as models for dark energy

We consider stochastically quantized self-interacting scalar fields as suitable models to generate dark energy in the universe. Second quantization effects lead to new and unexpected phenomena is the self interaction strength is strong. The stochastically quantized dynamics can degenerate to a chaotic dynamics conjugated to a Bernoulli shift in fictitious time, and the right amount of vacuum energy density can be generated without fine tuning. It is numerically observed that the scalar field dynamics distinguishes fundamental parameters such as the electroweak and strong coupling constants as corresponding to local minima in the dark energy landscape. Chaotic fields can offer possible solutions to the cosmological coincidence problem, as well as to the problem of uniqueness of vacua.Comment: 30 pages, 3 figures. Replaced by final version accepted by Phys. Rev.

Colonic transit in children and adolescents with chronic constipation

AbstractObjectiveThe aim of this study was to assess clinical features and colonic transit patterns in Brazilian children with refractory constipation.MethodsFrom 2010 to 2013, 79 constipated patients received follow-up care in a tertiary hospital. Of these patients, 28 (aged 8–14 years) were refractory to conventional therapy and underwent a simplified visual method of nuclear colonic transit study, by ingestion of a liquid meal containing 9.25MBq/kg of 99mTc-phytate. Abdominal static images were taken immediately and at two, six, 24, 30, and 48h after ingestion for qualitative analysis of the radio marker progression through the colon.ResultsTwo patterns of colonic transit were found: slow colonic transit (SCT, n=14), when images at 48h showed a larger part of the tracer remained in proximal and transverse colon, and distal retention (DR, n=14), when after 30h, the radio isotope passed the transverse colon and was retained in the rectosigmoid up to 48h. The SCT and DR group included, respectively, nine and ten males; median ages in the nuclear study of 11 and 10 years, p=0.207; median duration of constipation of seven and six years, p=0.599. Constipation appearing during first year age (p=0.04) and report of soft stools (p=0.02) were more common in SCT patients. Palpable abdominal fecal impaction was found only in DR group. Appendicostomy for antegrade continence enema was successful in 4/12 (30%) of SCT patients (median follow-up: 2.4 years).ConclusionNuclear transit study distinguished two colonic dysmotility patterns and was useful for guiding refractory patients to specific therapies

Ordering in the dilute weakly-anisotropic antiferromagnet Mn(0.35)Zn(0.65)F2

The highly diluted antiferromagnet Mn(0.35)Zn(0.65)F2 has been investigated by neutron scattering in zero field. The Bragg peaks observed below the Neel temperature TN (approximately 10.9 K) indicate stable antiferromagnetic long-range ordering at low temperature. The critical behavior is governed by random-exchange Ising model critical exponents (nu approximately 0.69 and gamma approximately 1.31), as reported for Mn(x)Zn(1-x)F2 with higher x and for the isostructural compound Fe(x)Zn(1-x)F2. However, in addition to the Bragg peaks, unusual scattering behavior appears for |q|>0 below a glassy temperature Tg approximately 7.0 K. The glassy region T<Tg corresponds to that of noticeable frequency dependence in earlier zero-field ac susceptibility measurements on this sample. These results indicate that long-range order coexists with short-range nonequilibrium clusters in this highly diluted magnet.Comment: 7 pages, 5 figure