KamLAND Bounds on Solar Antineutrinos and neutrino transition magnetic moments

We investigate the possibility of detecting solar electron antineutrinos with the KamLAND experiment. These electron antineutrinos are predicted by spin-flavor oscillations at a significant rate even if this mechanism is not the leading solution to the SNP. KamLAND is sensitive to antineutrinos originated from solar ${}^8$B neutrinos. From KamLAND negative results after 145 days of data taking, we obtain model independent limits on the total flux of solar electron antineutrinos $\Phi({}^8 B)< 1.1-3.5\times 10^4 cm^{-2}\ s^{-1}$, more than one order of magnitude smaller than existing limits, and on their appearance probability$P<0.15%$(95antineutrino production by spin-flavor precession, this upper bound implies an upper limit on the product of the intrinsic neutrino magnetic moment and the value of the solar magnetic field$\mu B< 2.3\times 10^{-21}$MeV 95LMA$(\Delta m^2, \tan^2\theta)$values). Limits on neutrino transition moments are also obtained. For realistic values of other astrophysical solar parameters these upper limits would imply that the neutrino magnetic moment is constrained to be, in the most conservative case,$\mu\lsim 3.9\times 10^{-12} \mu_B$(95CL) for a relatively small field$B= 50$kG. For higher values of the magnetic field we obtain:$\mu\lsim 9.0\times 10^{-13} \mu_B$for field$B= 200$kG and$\mu\lsim 2.0\times 10^{-13} \mu_B$for field$B= 1000$ kG at the same statistical significance.Comment: 13 pages, 2 figure

Adaptation to public goods cheats in Pseudomonas aeruginosa

This is the author accepted manuscript. The final version is available from the Royal Society via the DOI in this record.Cooperation in nature is ubiquitous, but is susceptible to social cheats who pay little or no cost of cooperation yet reap the benefits. The effect such cheats have on reducing population productivity suggests that there is selection for cooperators to mitigate the adverse effects of cheats. While mechanisms have been elucidated for scenarios involving a direct association between producer and cooperative product, it is less clear how cooperators may suppress cheating in an anonymous public goods scenario, where cheats cannot be directly identified. Here, we investigate the real-time evolutionary response of cooperators to cheats when cooperation is mediated by a diffusible public good: the production of iron-scavenging siderophores by Pseudomonas aeruginosa. We find that siderophore producers evolved in thepresence of a high frequency of non-producing cheats were fitter in the presence of cheats, at no obvious cost to population productivity. A novel morphotype independently evolved and reached higher frequencies in cheat-adapted versus control populations, exhibiting reduced siderophore production but increased production of pyocyanin - an extracellular toxin that can also increase the availability of soluble iron. This suggests that cooperators may have mitigated the negative effects of cheats by downregulating siderophore production and upregulating an alternative iron-acquisition public good. More generally, the study emphasises that cooperating organisms can rapidly adapt to the presence of anonymous cheats without necessarily incurring fitness costs in the environment they evolve in.The work was funded by AXA research fund, NERC, BBSRC and the Royal Society to AB and a University of Exeter PhD studentship to SOB

Relic Neutralino Density in Scenarios with Intermediate Unification Scale

We analyse the relic neutralino density in supersymmetric models with an intermediate unification scale. In particular, we present concrete cosmological scenarios where the reheating temperature is as small as $\cal{O}$ $1 - 1000$ MeV). When this temperature is associated to the decay of moduli fields producing neutralinos, we show that the relic abundance increases considerably with respect to the standard thermal production. Thus the neutralino becomes a good dark matter candidate with 0.1\lsim \Omega h^2 \lsim 0.3, even for regions of the parameter space where large neutralino-nucleon cross sections, compatible with current dark matter experiments, are present. This is obtained for intermediate scales $M_I\sim 10^{11}-10^{14}$ GeV, and moduli masses $m_\phi\sim 100-1000$ GeV. On the other hand, when the above temperature is associated to the decay of an inflaton field, the relic abundance is too small.Comment: Latex, 11 pages, 2 figure

KamLAND, solar antineutrinos and the solar magnetic field

In this work the possibility of detecting solar electron antineutrinos produced by a solar core magnetic field from the KamLAND recent observations is investigated. We find a scaling of the antineutrino probability with respect to the magnetic field profile in the sense that the same probability function can be reproduced by any profile with a suitable peak field value. In this way the solar electron antineutrino spectrum can be unambiguosly predicted. We use this scaling and the negative results indicated by the KamLAND experiment to obtain upper bounds on the solar electron antineutrino flux. We get $\phi_{\bar\nu}<3.8\times 10^{-3}\phi(^8B)$ at 95% CL. For 90% CL this becomes $\phi_{\bar\nu}<3.4\times 10^{-3}\phi(^8B)$, an improvement by a factor of 3-5 with respect to existing bounds. These limits are independent of the detailed structure of the magnetic field in the solar interior. We also derive upper bounds on the peak field value which are uniquely determined for a fixed solar field profile. In the most efficient antineutrino producing case, we get (95% CL) an upper limit on the product of the neutrino magnetic moment by the solar field $\mu B< 2.8\times 10^{-19}$ MeV or $B_0 \leq 4.9 \times 10^7 G$ for $\mu_\nu=10^{-12}\mu_B$.Comment: 15 pages. References corrected. Minor changes in the tex

Las playas de Tulum en la Riviera maya mexicana: caracterización y diagnóstico como base del manejo integrado costero

En el contexto del Programa Hacia la Certificación de la Calidad de las Playas de Tulum, que viene desarrollando la Unidad de Atención a Playas - Tulum, adscripta a la Fundación Orígenes de Quintana Roo (México), durante el primer trimestre del año 2008 se realizó un exhaustivo trabajo de campo que permitió actualizar la Caracterización general y el Diagnóstico físico-ambiental de este sector costero. En este trabajo se presenta una descripción sintetizada de los rasgos físicogeográficos de las playas y se identifican los principales problemas ambientales que las afectan actualmente, para finalmente esbozar los lineamientos generales que perrrútirán continuar avanzando hacia la conformación de un Programa de Manejo integrado costero y Certificación de las playas de Tulum.By the context of the "Programa Hacia la Certificación de la Calidad de las Playas de Tulum", which is developing by the "Unidad de Atención a Playas - Tulum" , attached to the "Fundación Orígenes de Quintana Roo" (Mexico), during the first quarter of 2008, was a comprehensive work allowing field upgrade a physical-environment characterization and diagnostics of this coastal sector. This paper presents a summary description of the physical-geographical features of the beaches and identifies the main environmental problems that affect them now, and finally outline the general guidelines that allow us to continue moving toward the establishment of an Integrated Coastal Management Program and Certification from the beaches of Tulum

Development of learning objectives for neurology in a veterinary curriculum: Part II: Postgraduates

Background: Specialization in veterinary medicine in Europe is organized through the Colleges of the European Board of Veterinary Specialization. To inform updating of the curriculum for residents of the European College of Veterinary Neurology (ECVN) job analysis was used. Defining job competencies of diploma holders in veterinary neurology can be used as references for curriculum design of resident training. With the support of the diplomates of the ECVN and the members of the European Society of Veterinary Neurology (ESVN) a mixed-method research, including a qualitative search of objectives and quantitative ranking with 149 Likert scale questions and 48 free text questions in 9 categories in a survey was conducted. In addition, opinions of different groups were subjected to statistical analysis and the result compared. Results: A return rate of 62% (n = 213/341) was achieved. Of the competencies identified by the Delphi process, 75% objectives were expected to attain expert level; 24% attain advanced level; 1% entry level. In addition, the exercise described the 11 highly ranked competencies, the 3 most frequently seen diseases of the central and peripheral nervous systems and the most frequently used immunosuppressive, antiepileptic and chemotherapeutic drugs. Conclusion: The outcomes of this “Delphi job analysis” provide a powerful tool to align the curriculum for ECVN resident training and can be adapted to the required job competencies, based on expectations. The expectation is that for majority of these competencies diplomates should attain an expert level. Besides knowledge and clinical skills, residents and diplomates are expected to demonstrate high standards in teaching and communication. The results of this study will help to create a European curriculum for postgraduate education in veterinary neurology

A comprehensive study of neutrino spin-flavour conversion in supernovae and the neutrino mass hierarchy

Resonant spin-flavour (RSF) conversions of supernova neutrinos, which is induced by the interaction between the nonzero neutrino magnetic moment and supernova magnetic fields, are studied for both normal and inverted mass hierarchy. As the case for the pure matter-induced neutrino oscillation (Mikheyev--Smirnov--Wolfenstein (MSW) effect), we find that the RSF transitions are strongly dependent on the neutrino mass hierarchy as well as the value of $\theta_{13}$. Flavour conversions are solved numerically for various neutrino parameter sets, with presupernova profile calculated by Woosley and Weaver. In particular, it is very interesting that the RSF-induced \nu_\rme\to\bar\nu_\rme transition occurs, if the following conditions are all satisfied: the value of $\mu_\nu B$ ($\mu_\nu$ is the neutrino magnetic moment, and $B$ is the magnetic field strength) is sufficiently strong, the neutrino mass hierarchy is inverted, and the value of $\theta_{13}$ is large enough to induce adiabatic MSW resonance. In this case, the strong peak due to original \nu_\rme emitted from neutronization burst would exist in time profile of the neutrino events detected at the Super-Kamiokande detector. If this peak were observed in reality, it would provide fruitful information on the neutrino properties. On the other hand, characters of the neutrino spectra are also different between the neutrino models, but we find that there remains degeneracy among several models. Dependence on presupernova models is also discussed.Comment: 23 pages, 11 figures, corrected minor typos, added references. Final version to appear in Journal of Cosmology and Astroparticle Physic

Feature selection for chemical sensor arrays using mutual information

We address the problem of feature selection for classifying a diverse set of chemicals using an array of metal oxide sensors. Our aim is to evaluate a filter approach to feature selection with reference to previous work, which used a wrapper approach on the same data set, and established best features and upper bounds on classification performance. We selected feature sets that exhibit the maximal mutual information with the identity of the chemicals. The selected features closely match those found to perform well in the previous study using a wrapper approach to conduct an exhaustive search of all permitted feature combinations. By comparing the classification performance of support vector machines (using features selected by mutual information) with the performance observed in the previous study, we found that while our approach does not always give the maximum possible classification performance, it always selects features that achieve classification performance approaching the optimum obtained by exhaustive search. We performed further classification using the selected feature set with some common classifiers and found that, for the selected features, Bayesian Networks gave the best performance. Finally, we compared the observed classification performances with the performance of classifiers using randomly selected features. We found that the selected features consistently outperformed randomly selected features for all tested classifiers. The mutual information filter approach is therefore a computationally efficient method for selecting near optimal features for chemical sensor arrays

Parental and familial factors influencing physical activity levels in early adolescence: a prospective study

Parental/familial factors are important determinants of the physical activity level (PAL) in children and adolescents, but studies rarely prospectively evaluate their relationships. This study aimed to evaluate the changes in physical activity levels among adolescents from Bosnia and Herzegovina over a two-year period and to determine parental/familial predictors of PAL in early adolescence. A total of 651 participants (50.3% females) were tested at baseline (beginning of high school education; 14 years old on average) and at follow-up (approximately 20 months later). The predictors included sociodemographic characteristics (age, gender) and parental/familial factors (socioeconomic status of the family, maternal and paternal education, conflict with parents, parental absence from home, parental questioning, and parental monitoring). Physical activity levels were evidenced by the Physical Activity Questionnaire for Adolescents (PAQ-A; criterion). Boys were more active than girls, both at baseline (t-test = 3.09, p &lt; 0.001) and at follow-up (t-test = 3.4, p &lt; 0.001). Physical activity level decreased over the observed two-year period (t-test = 16.89, p &lt; 0.001), especially in boys, which is probably a consequence of drop-out from the sport in this period. Logistic regression evidenced parental education as a positive predictor of physical activity level at baseline (OR [95% CI]; 1.38 [1.15–170], 1.35 [1.10–1.65]), and at follow-up (1.35 [1.11–1.69], 1.29 [1.09–1.59], for maternal and paternal education, respectively). Parents with a higher level of education are probably more informed about the importance of physical activity on health status, and thus transfer this information to their children as well. The age from 14 to 16 years is likely a critical period for maintaining physical activity levels in boys, while further studies of a younger age are necessary to evaluate the dynamics of changes in physical activity levels for girls. For maintaining physical activity levels in adolescence, special attention should be paid to children whose parents are less educated, and to inform them of the benefits of an appropriate physical activity level and its necessity for maintaining proper health and growth