Dermatitis crónica por sensibilización al níquel en un paciente con fractura del astrágalo tratada mediante osteosíntesis

Se presenta un varón de 25 años, con fractura del astrágalo izquierdo tratada mediante osteosíntesis con 2 tornillos de acero inoxidable con un contenido en níquel del 12-14%. A los 4 meses de la intervención, el paciente desarrolló una dermatitis pruriginosa en cara lateral externa del pie, en la zona cutánea supra-adyacente al lugar de la osteosíntesis. La lesión no cedió con el tratamiento tópico convencional a base de corticoides. Las pruebas epicutáneas realizadas con la batería estándar del Grupo Español de Investigación en Dermatitis de Contacto revelaron un parche positivo vesiculoso (+ +) al sulfato de níquel al 2,5% y al cloruro de cobalto al 1%, ambos aplicados en vaselina, en la lectura a las 48 y 96 horas. En vista de que las lesiones permanecían estables al mes de tratamiento con un potente corticoide en cura oclusiva y antihistamínicos sistémicos, se procedió a retirar los tornillos de osteosíntesis. A los pocos días de la intervención comenzó a desaparecer el prurito y, en el curso de 2 semanas, se produjo la curación completa de la dermatitisSe presenta un varón de 25 años, con fractura del astrágalo izquierdo tratada mediante osteosíntesis con 2 tornillos de acero inoxidable con un contenido en níquel del 12-14%. A los 4 meses de la intervención, el paciente desarrolló una dermatitis pruriginosa en cara lateral externa del pie, en la zona cutánea supra-adyacente al lugar de la osteosíntesis. La lesión no cedió con el tratamiento tópico convencional a base de corticoides. Las pruebas epicutáneas realizadas con la batería estándar del Grupo Español de Investigación en Dermatitis de Contacto revelaron un parche positivo vesiculoso (+ +) al sulfato de níquel al 2,5% y al cloruro de cobalto al 1%, ambos aplicados en vaselina, en la lectura a las 48 y 96 horas. En vista de que las lesiones permanecían estables al mes de tratamiento con un potente corticoide en cura oclusiva y antihistamínicos sistémicos, se procedió a retirar los tornillos de osteosíntesis. A los pocos días de la intervención comenzó a desaparecer el prurito y, en el curso de 2 semanas, se produjo la curación completa de la dermatitis

Memorino on the `1/2 vs. 3/2 Puzzle' in Bˉ→lνˉXc\bar B \to l \bar \nu X_c

After the successes the OPE description has scored in describing $\bar B \to l \bar \nu X_c$ decays, we need to study what can be said about the composition of the hadronic final state $X_c$. The same OPE treatment yields sum rules implying the dominance of $j_q = 3/2$ charm states in $X_c$ over their $j_q=1/2$ counterparts. This prediction is supported by other general arguments as well as quark model calculations. At present it is unclear to which degree data conform to these predictions. More experimental information is essential. We want to ask our experimental colleagues for a redoubled effort to establish, which hadronic configurations -- $D/D^* + \pi, D/D^* + 2 \pi, ...$ -- make up $\Gamma (\bar B \to l \bar \nu X_c)$ beyond $\bar B \to l \bar \nu D/D^*$, what their quantum numbers are and their mass distributions. The latter is most relevant for the determination of hadronic mass moments in $\bar B \to l \bar \nu X_c$. Since all this will require considerable effort on their part, we want to explain the theoretical issues involved, why they carry `gravitas' -- i.e. are weighty -- and why a better understanding of them will be of significant value. In this brief memo we sketch the underlying arguments based on heavy quark theory, the OPE, a special class of quark models and lattice QCD in a nutshell. After summarizing the experimental situation we conclude with two lists, namely one with measurements that need to be done and one with items of theoretical homework. Some of the latter can be done by employing existing theoretical tools, whereas others need new ideas.Comment: 13 pages, no figure

Autoestima, dependencia emocional y celos: un modelo explicativo en estudiantes universitarios peruanos

Emotional dependence is characterized by an extreme emotional need of the partner expressed in behaviors aimed at seeking attention and avoiding unpleasant feelings, such as fear of loneliness or separation anxiety. Jealousy is a behavior whose frequency and intensity are related to the degree of emotional dependence, as it denotes feelings of insecurity facing the potential threat of losing the emotional bond with the partner. In both cases, the literature suggests that self-esteem plays an important role in the dynamic between emotional dependence and jealousy. The objective of this research is to postulate an explanatory model where the relationship between emotional dependence and jealousy is recognized, and self-esteem is proposed as a predictor of both variables among Peruvian undergraduate students. A cross-sectional design was used in a sample of 819 university students with partners, 37.73% men and 62.27% women. The instruments used were the following: Rosenberg self-esteem scale, emotional communication scale in romantic relationships (jealousy subscale) and emotional dependence scale. Constructs were modeled using confirmatory factor analysis, and factor scores were used in path analysis as part of structural equation modeling. The results indicate that self-esteem is a moderate predictor of emotional dependence and, to a lesser extent, jealousy; while emotional dependence presents a moderate relationship with jealousy, even after controlling the effect of self-esteem. In conclusion, the results represent evidence that supports intervention on self-esteem as an alternative to mitigate the degree of severity of emotional dependence, as well as the indirect reduction of the intensity and frequency of jealousy among university students.La dependencia emocional se caracteriza por una necesidad afectiva extrema de la pareja expresada en comportamientos orientados a la búsqueda de atención y a la evasión de sentimientos displacenteros como el miedo a la soledad o la ansiedad de separación. Los celos son comportamientos cuya frecuencia e intensidad se relacionan con el grado de dependencia emocional, pues denotan sentimientos de inseguridades frente a la potencial amenaza de perder el vínculo emocional con la pareja. En ambos casos, la literatura sugiere que la autoestima ejerce un rol importante frente a la dinámica entre la dependencia emocional y los celos. El objetivo de la presente investigación es postular un modelo explicativo en donde se reconoce la relación entre la dependencia emocional y los celos, y se propone a la autoestima como un predictor de ambas variables en estudiantes peruanos de pregrado. Se empleó un diseño transversal en una muestra de 819 estudiantes universitarios con parejas, 37.73 % varones y 62.27 % mujeres. Los instrumentos utilizados fueron los siguientes: escala de autoestima de Rosenberg, escala de comunicación emocional en las relaciones románticas (subescala de celos) y escala de dependencia emocional. Los constructos fueron modelados utilizando análisis factorial confirmatorio y los puntajes factoriales fueron empleados en un análisis de senderos como parte de un modelamiento de ecuaciones estructurales. Los resultados indican que la autoestima es un predictor moderado de la dependencia emocional y, en menor parte, de los celos; mientras que la dependencia emocional presenta una relación moderada con los celos, incluso luego de controlar el efecto de la autoestima. En conclusión, los resultados representan evidencia que sustenta la intervención sobre la autoestima como alternativa para mitigar el grado de severidad de la dependencia emocional, así como la reducción indirecta de la intensidad y la frecuencia de los celos en estudiantes universitarios

Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−

The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

Measurement of the relative rate of prompt χc0, χc1 and χc2 production at √s=7TeV

Prompt production of charmonium χc0, χc1 and χc2 mesons is studied using proton-proton collisions at the LHC at a centre-of-mass energy of √s=7TeV. The χc mesons are identified through their decay to J/ψγ, with J/ψ→μ+mu− using photons that converted in the detector. A data sample, corresponding to an integrated luminosity of 1.0fb−1 collected by the LHCb detector, is used to measure the relative prompt production rate of χc1 and χc2 in the rapidity range 2.0<y<4.5 as a function of the J/ψ transverse momentum from 3 to 20 GeV/c. First evidence for χc0 meson production at a hadron collider is also presented

Observation of two new Ξb−\Xi_b^- baryon resonances

Two structures are observed close to the kinematic threshold in the $\Xi_b^0 \pi^-$ mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb$^{-1}$ recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content $bds$ are expected in this mass region: the spin-parity $J^P = \frac{1}{2}^+$ and $J^P=\frac{3}{2}^+$ states, denoted $\Xi_b^{\prime -}$ and $\Xi_b^{*-}$. Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be $m(\Xi_b^{\prime -}) - m(\Xi_b^0) - m(\pi^{-}) = 3.653 \pm 0.018 \pm 0.006$ MeV$/c^2$, $m(\Xi_b^{*-}) - m(\Xi_b^0) - m(\pi^{-}) = 23.96 \pm 0.12 \pm 0.06$ MeV$/c^2$, $\Gamma(\Xi_b^{*-}) = 1.65 \pm 0.31 \pm 0.10$ MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of $\Gamma(\Xi_b^{\prime -}) < 0.08$ MeV at 95% confidence level. Relative production rates of these states are also reported.Comment: 17 pages, 2 figure

Study of DJ meson decays to D+π−, D0π+ and D∗+π− final states in pp collisions

A study of D+π−, D0π+ and D∗+π− final states is performed using pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected at a centre-of-mass energy of 7 TeV with the LHCb detector. The D1(2420)0 resonance is observed in the D∗+π− final state and the D∗2(2460) resonance is observed in the D+π−, D0π+ and D∗+π− final states. For both resonances, their properties and spin-parity assignments are obtained. In addition, two natural parity and two unnatural parity resonances are observed in the mass region between 2500 and 2800 MeV. Further structures in the region around 3000 MeV are observed in all the D∗+π−, D+π− and D0π+ final states

Search for the decay Bs0→D*∓π±

A search for the decay Bs0→D*∓π± is presented using a data sample corresponding to an integrated luminosity of 1.0  fb-1 of pp collisions collected by LHCb. This decay is expected to be mediated by a W-exchange diagram, with little contribution from rescattering processes, and therefore a measurement of the branching fraction will help us to understand the mechanism behind related decays such as Bs0→π+π- and Bs0→DD- . Systematic uncertainties are minimized by using B0→D*∓π± as a normalization channel. We find no evidence for a signal, and set an upper limit on the branching fraction of B(Bs0→D*∓π±)<6.1(7.8)×10-6 at 90% (95%) confidence level

Search for CP violation in D+→ϕπ+ and D+s→K0Sπ+ decays

A search for CP violation in D + → ϕπ + decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb−1 at a centre of mass energy of 7 TeV. The CP -violating asymmetry is measured to be (−0.04 ± 0.14 ± 0.14)% for candidates with K − K + mass within 20 MeV/c 2 of the ϕ meson mass. A search for a CP -violating asymmetry that varies across the ϕ mass region of the D + → K − K + π + Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D+s→K0Sπ+ decay is measured to be (0.61 ± 0.83 ± 0.14)%